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  • 1. Bachmann, A.
    et al.
    Borgelt, C.
    Gidófalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Incremental frequent route based trajectory prediction2013Ingår i: IWCTS 2013 - 6th ACM SIGSPATIAL International Workshop on Computational Transportation Science, Association for Computing Machinery (ACM), 2013, s. 49-54Konferensbidrag (Refereegranskat)
    Abstract [en]

    Recent technological trends enable modern traffic prediction and management systems in which the analysis and prediction of movements of objects is essential. To this extent the present paper proposes IncCCFR - a novel, incremental approach for managing, mining, and predicting the incrementally evolving trajectories of moving objects. In addition to reduced mining and storage costs, a key advantage of the incremental approach is its ability to combine multiple temporally relevant mining results from the past to capture temporal and periodic regularities in movement. The approach and its variants are empirically evaluated on a large real-world data set of moving object trajectories, originating from a fleet of taxis, illustrating that detailed closed frequent routes can be efficiently discovered and used for prediction.

  • 2.
    Beatrix Cleff, Evelyn
    et al.
    Aarhus University, School of Business.
    Gidofalvi, Gyözö
    Geomatic ApS - Center for Geoinformatics .
    The legal aspects of a location-based mobile advertising platform2008Ingår i: International Journal of Intellectual Property Management, ISSN 1478-9647, Vol. 2, nr 3, s. 261-275Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent advances in Information and Communication Technology (ICT), such as the increasing accuracy of Global Positioning Systems (GPSs) technology and the miniaturisation of wireless communication devices, pave the road for Location-Based Services (LBSs). Among these services, m-advertising is predicted to represent a high-yield revenue stream. In this article, the possibilities of using a Location-Aware Mobile Messenger (LAMM) for the purpose of m-advertising is introduced. To avoid m-advertising becoming an extremely intrusive practice by neglecting the user's privacy, the objective of this article is to introduce a location-based advertising platform which complies with the provisions imposed by European Union (EU) law with regard to personal data protection.

  • 3.
    Cumbane, Silvino Pedro
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Review of Big Data and Processing Frameworks for Disaster Response Applications2019Ingår i: ISPRS International Journal of Geo-Information, ISSN 2220-9964, Vol. 8, nr 9, artikel-id 387Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Natural hazards result in devastating losses in human life, environmental assets and personal, and regional and national economies. The availability of different big data such as satellite imageries, Global Positioning System (GPS) traces, mobile Call Detail Records (CDRs), social media posts, etc., in conjunction with advances in data analytic techniques (e.g., data mining and big data processing, machine learning and deep learning) can facilitate the extraction of geospatial information that is critical for rapid and effective disaster response. However, disaster response systems development usually requires the integration of data from different sources (streaming data sources and data sources at rest) with different characteristics and types, which consequently have different processing needs. Deciding which processing framework to use for a specific big data to perform a given task is usually a challenge for researchers from the disaster management field. Therefore, this paper contributes in four aspects. Firstly, potential big data sources are described and characterized. Secondly, the big data processing frameworks are characterized and grouped based on the sources of data they handle. Then, a short description of each big data processing framework is provided and a comparison of processing frameworks in each group is carried out considering the main aspects such as computing cluster architecture, data flow, data processing model, fault-tolerance, scalability, latency, back-pressure mechanism, programming languages, and support for machine learning libraries, which are related to specific processing needs. Finally, a link between big data and processing frameworks is established, based on the processing provisioning for essential tasks in the response phase of disaster management.

  • 4.
    Cumbane, Silvino Pedro
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Spatial Distribution of Displaced Population Estimated Using Mobile Phone Data to Support Disaster Response Activities2021Ingår i: ISPRS International Journal of Geo-Information, ISSN 2220-9964, Vol. 10, nr 6, s. 421-, artikel-id 421Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Under normal circumstances, people's homes and work locations are given by their addresses, and this information is used to create a disaster management plan in which there are instructions to individuals on how to evacuate. However, when a disaster strikes, some shelters are destroyed, or in some cases, distance from affected areas to the closest shelter is not reasonable, or people have no possibility to act rationally as a natural response to physical danger, and hence, the evacuation plan is not followed. In each of these situations, people tend to find alternative places to stay, and the evacuees in shelters do not represent the total number of the displaced population. Knowing the spatial distribution of total displaced people (including people in shelters and other places) is very important for the success of the response activities which, among other measures, aims to provide for the basic humanitarian needs of affected people. Traditional methods of people displacement estimation are based on population surveys in the shelters. However, conducting a survey is infeasible to perform at scale and provides low coverage, i.e., can only cover the numbers for the population that are at the shelters, and the information cannot be delivered in a timely fashion. Therefore, in this research, anonymized mobile Call Detail Records (CDRs) are proposed as a source of information to infer the spatial distribution of the displaced population by analyzing the variation of home cell-tower for each anonymized mobile phone subscriber before and after a disaster. The effectiveness of the proposed method is evaluated using remote-sensing-based building damage assessment data and Displacement Tracking Matrix (DTM) from an individual's questionnaire survey conducted after a severe cyclone in Beira city, central Mozambique, in March 2019. The results show an encouraging correlation coefficient (over 70%) between the number of arrivals in each neighborhood estimated using CDRs and from DTM. In addition to this, CDRs derive spatial distribution of displaced populations with high coverage of people, i.e., including not only people in the shelter but everyone who used a mobile phone before and after the disaster. Moreover, results suggest that if CDRs data are available right after a disaster, population displacement can be estimated, and this information can be used for response activities and hence contribute to reducing waterborne diseases (e.g., diarrheal disease) and diseases associated with crowding (e.g., acute respiratory infections) in shelters and host communities.

  • 5.
    Cumbane, Silvino Pedro
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Yang, Can
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    A Framework for Traffic Prediction Integrated with Deep Learning2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    City-scale traffic prediction is an important task for public safety, traffic management, and deployment of intelligent transportation systems. Many approaches have been proposed to address traffic prediction task using machine learning techniques. In this paper, we present a framework to help on addressing the task at hand (density-, traffic flow- and origin-destination flow predictions) considering data type, features, deep learning techniques such as Convolutional Neural Networks (CNNs), e.g., Autoencoder, Recurrent Neural Networks (RNNs), e.g., Long Short Term Memory (LSTM), and Graph Convolutional Networks (GCNs). An autoencoder model is designed in this paper to predict traffic density based on historical data. Experiments on real-world taxi order data demonstrate the effectiveness of the model.

    Ladda ner fulltext (pdf)
    Traffic_Prediction_Framework
  • 6.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    A Mobile Consumer Analysis Platform2010Ingår i: Proceedings of the Workshop on Innovation in Movement Behaviour Analysis: 7th International Conference on Methods and Techniques in Behavioral Research, August 24 - 27, 2010, Eindhoven, Netherlands, 2010, s. 2-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Advances in mobile communication, computing and positioning technologies allow the real–time acquisition of continuously evolving locations of moving objects, e.g., users carrying location-aware mobile devices. This short paper proposes the geo-contextual analysis and data mining of these location traces to deliver deep insight into consumer behavior and enable a number of promising Business Intelligence services.

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  • 7.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Scalable Selective Traffic Congestion Notification2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Congestion is a major problem in most metropolitan areas. Systems that can in a timely manner inform drivers about relevant, current or predicted traffic congestion are paramount for effective traffic management. Without loss of generality, this paper proposes such a system that by adopting a grid-based discretization of space, can flexibly scale the computation cost and the geographic level of detail of traffic information that it provides. From the continuous stream of grid-based position and speed reports from vehicles, the system incrementally derives 1) statistics for detecting directional traffic congestions and 2) model parameters for a time-inhomogeneous, Markov jump process that is used to predict the likelihood that a given vehicle will encounter a detected directional congestion within the notification horizon. A simple but efficient SQL-based prototype implementation of the system that can naturally be ported to Big Data processing frameworks is also explained in detail. Empirical evaluations on millions of object trajectories show that 1) the proposed movement model captures the topology of the underlying road network space and the directional aspects of movement on it, 2) the congestion notification accuracy of the system is superior to a linear movement model based system, and 3) the prototype implementation of the system (i) scales linearly with its input load, notification horizon and spatio-temporal resolution and (ii) can in real-time process 1.14 million object trajectories.

  • 8.
    Gidofalvi, Gyözö
    Geomatic ApS - Center for Geoinformatics.
    Spatio-Temporal Data Mining for Location-Based Services2008Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Largely driven by advances in communication and information technology, such as the increasing availability and accuracy of GPS technology and the miniaturization of wireless communication devices, Location–Based Services (LBS) are continuously gaining popularity. Innovative LBSes integrate knowledge about the users into the service. Such knowledge can be derived by analyzing the location data of users. Such data contain two unique dimensions, space and time, which need to be analyzed.

    The objectives of this thesis are three–fold. First, to extend popular data mining methods to the spatio–temporal domain. Second, to demonstrate the usefulness of the extended methods and the derived knowledge in two promising LBS examples. Finally, to eliminate privacy concerns in connection with spatio–temporal data mining by devising systems for privacy–preserving location data collection and mining.

     

    To this extent, Chapter 2 presents a general methodology, pivoting, to extend a popular data mining method, namely rule mining, to the spatio–temporal domain. By considering the characteristics of a number of real–world data sources, Chapter 2 also derives a taxonomy of spatio–temporal data, and demonstrates the usefulness of the rules that the extended spatio–temporal rule mining method can discover. In Chapter 4 the proposed spatio–temporal extension is applied to find long, sharable patterns in trajectories of moving objects. Empirical evaluations show that the extended method and its variants, using high–level SQL implementations, are effective tools for analyzing trajectories of moving objects.

    Real–world trajectory data about a large population of objects moving over extended periods within a limited geographical space is difficult to obtain. To aid the development in spatio–temporal data management and data mining, Chapter 3 develops a Spatio–Temporal ACTivity Simulator (ST–ACTS). ST–ACTS uses a number of real–world geo–statistical data sources and intuitive principles to effectively generate realistic spatio–temporal activities of mobile users.

     

    Chapter 5 proposes an LBS in the transportation domain, namely cab–sharing. To deliver an effective service, a unique spatio–temporal grouping algorithm is presented and implemented as a sequence of SQL statements. Chapter 6 identifies ascalability bottleneck in the grouping algorithm. To eliminate the bottleneck, the chapter expresses the grouping algorithm as a continuous stream query in a data stream management system, and then devises simple but effective spatio–temporal partitioning methods for streams to parallelize the computation. Experimental results show that parallelization through adaptive partitioning methods leads to speed–ups of orders of magnitude without significantly effecting the quality of the grouping. Spatio–temporal stream partitioning is expected to be an effective method to scale computation–intensive spatial queries and spatial analysis methods for streams.

     

    Location–Based Advertising (LBA), the delivery of relevant commercial information to mobile consumers, is considered to be one of the most promising business opportunities amongst LBSes. To this extent, Chapter 7 describes an LBA framework and an LBA database that can be used for the management of mobile ads. Using a simulated but realistic mobile consumer population and a set of mobile ads, the LBA database is used to estimate the capacity of the mobile advertising channel. The estimates show that the channel capacity is extremely large, which is evidence for a strong business case, but it also necessitates adequate user controls.

     

    When data about users is collected and analyzed, privacy naturally becomes a concern. To eliminate the concerns, Chapter 8 first presents a grid–based framework in which location data is anonymized through spatio–temporal generalization, and then proposes a system for collecting and mining anonymous location data. Experimental results show that the privacy–preserving data mining component discovers patterns that, while probabilistic, are accurate enough to be useful for many LBSes.

     

    To eliminate any uncertainty in the mining results, Chapter 9 proposes a system for collecting exact trajectories of moving objects in a privacy–preserving manner. In the proposed system there are no trusted components and anonymization is performed by the clients in a P2P network via data cloaking and data swapping. Realistic simulations show that under reasonable conditions and privacy/anonymity settings the proposed system is effective.

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  • 9.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Ehsan, Saqib
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Developing a Benchmark for Using Trajectories of Moving Objects in Traffic Prediction and Management2010Konferensbidrag (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    fulltext
  • 10.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Ehsan, Saqib
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    From Trajectories of Moving Objects to Route-Based Traffic Prediction and Management2010Ingår i: Proceedings of the Workshop on Movement Pattern Analysis 2010, Zurich, Switzerland, September 14, 2010. / [ed] Björn Gottfried and Patrick Laube and Alexander Klippel andNico Van de Weghe and Roland Billen, CEUR , 2010, s. 132-135Konferensbidrag (Refereegranskat)
  • 11.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Ehsan, Saqib
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Using Trajectories of Moving Objects in Traffic Prediction and Management2010Konferensbidrag (Refereegranskat)
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    fulltext
  • 12.
    Gidofalvi, Gyözö
    et al.
    Uppsala University, Department of Computer Science.
    Herenyi, Gergely
    Bach Pedersen, Torben
    Instant Social Ride-Sharing2008Ingår i: Proceedings of the Fifteenth World Congress on Intelligent Transport Systems, Nov 16-20, 2008, New York, NY, USA, Intelligent Transportation Society of America , 2008, s. 8-Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper explores the use of ride–sharing as a resource-efficient mode of personal transportation. While the perceived benefits of ride–sharing include reduced travel times, transportation costs, congestion, and carbon emissions, its wide–spread adoption is hindered by a number of barriers. These include the scheduling and coordination of routes, safety risks, social discomfort in sharing private spaces, and an imbalance of costs and benefits among parties. To address these barriers, the authors describe a system for ride–sharing that utilizing the concepts of social networks and social interest groups. The Social Ride/Sharing Service (SRSS) automatically groups ride offers and requests into ride–shares according to two objectives: to minimize ride–share detours, and to maximize the amount of social connections amongst participants of ride–shares. A mobile application places the SRSS at the fingertips of mobile users (anyplace and anytime), Minimizing detours and maximizing social connections in ride–shares is used to increase the social comfort level and trust among ride-share participants, ultimately leading to increased user acceptance and adoption of ride–sharing. As the number of users increases, the number of social connections between users increases, which allows more ride–share opportunities and more effective transport. The authors present realistic, city–wide simulations for Copenhagen that demonstrate that their proposed social ride–sharing system is viable and effective.

    Ladda ner fulltext (pdf)
    fulltext
  • 13.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center of Geoinformatics.
    Huang, Xuegang
    Aalborg University, Department of Computer Science.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Privacy-Preserving Data Mining on Moving Object Trajectories2007Ingår i: 2007 International Conference on Mobile Data Management / [ed] Christian Becker and Christian S. Jensen and Jianwen Su and Daniela Nicklas, IEEE conference proceedings, 2007, s. 60-68Konferensbidrag (Refereegranskat)
    Abstract [en]

    The popularity of embedded positioning technologies in mobile devices and the development of mobile communication technology have paved the way for powerful location-based services (LBSs). To make LBSs useful and user–friendly, heavy use is made of context information, including patterns in user location data which are extracted by data mining methods. However, there is a potential conflict of interest: the data mining methods want as precise data as possible, while the users want to protect their privacy by not disclosing their exact movements. This paper aims to resolve this conflict by proposing a general framework that allows user location data to be anonymized, thus preserving privacy, while still allowing interesting patterns to be discovered. The framework allows users to specify individual desired levels of privacy that the data collection and mining system will then meet. Privacy-preserving methods are proposed for a core data mining task, namely finding dense spatio–temporal regions. An extensive set of experiments evaluate the methods, comparing them to their non-privacy-preserving equivalents. The experiments show that the framework still allows most patterns to be found, even when privacy is preserved.

  • 14.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics .
    Huang, Xuegang
    Aalborg University, Department of Computer Science.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Privacy-Preserving Data Mining on Moving Object Trajectories2007Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The popularity of embedded positioning technologies in mobile devices and the development of mobile communication technology have paved the way for powerful location-based services (LBSs). To make LBSs useful and user–friendly, heavy use is made of context information, including patterns in user location data which are extracted by data mining methods. However, there is a potential conflict of interest: the data mining methods want as precise data as possible, while the users want to protect their privacy by not disclosing their exact movements. This paper aims to resolve this conflict by proposing a general framework that allows user location data to be anonymized, thus preserving privacy, while still allowing interesting patterns to be discovered. The framework allows users to specify individual desired levels of privacy that the data collection and mining system will then meet. Privacy-preserving methods are proposed for two core data mining tasks, namely finding dense spatio–temporal regions and finding frequent routes. An extensive set of experiments evaluate the methods, comparing them to their non-privacy-preserving equivalents. The experiments show that the framework still allows most patterns to be found, even when privacy is preserved.

    Ladda ner fulltext (pdf)
    fulltext
  • 15.
    Gidofalvi, Gyözö
    et al.
    Uppsala University, Department of Information Technology.
    Huang, Xuegang
    Aalborg University, Department of Computer Science.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Privacy-preserving trajectory collection2008Ingår i: GIS: Proceedings of the ACM International Symposium on Advances in Geographic Information Systems / [ed] Walid G. Aref and Mohamed F. Mokbel and Markus Schneider, ACM Press, 2008, s. 387-390Konferensbidrag (Refereegranskat)
    Abstract [en]

    In order to provide context–aware Location–Based Services, real location data of mobile users must be collected and analyzed by spatio–temporal data mining methods. However, the data mining methods need precise location data, while the mobile users want to protect their location privacy. To remedy this situation, this paper first formally defines novel location privacy requirements. Then, it briefly presents a system for privacy–preserving trajectory collection that meets these requirements. The system is composed of an untrusted server and clients communicating in a P2P network. Location data is anonymized in the system using data cloaking and data swapping techniques. Finally, the paper empirically demonstrates that the proposed system is effective and feasible.

  • 16.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Huang, Xuegang
    Aalborg University, Department of Computer Science.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Probabilistic Grid-Based Approaches for Privacy-Preserving Data Mining on Moving Object Trajectories2010Ingår i: Privacy-Aware Knowledge Discovery : Novel Applications and New Techniques / [ed] Francesco Bonchi and Elena Ferrari, CRC Press, 2010, 1, s. 183-210Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The efficient management of moving object databases has gained much interest in recent years due to the development of mobile communication and positioning technologies. A typical way of representing moving objects is to use the trajectories. Much work in the database community has focused on the topics of indexing, query processing and data mining of moving object trajectories, but little attention has been paid to the preservation of privacy in this setting.

     

    In many applications such as intelligent transport systems (ITS) and fleet management, floating car data (FCD), i.e., tracked vehicle locations, are collected, and used for mining traffic patterns. For instance, by mining vehicle trajectories in urban transportation networks over time one can easily identify dense areas (roads, junctions, etc.), and use this knowledge to predict traffic congestion. By data mining the periodic movement patterns (objects follow similar routes at similar times) of individual drivers, personalized, context–aware services can be delivered. However, exposing location / trajectory data of moving objects to application servers can cause threats to the location privacy of individual users. For example, a service provider with access to trajectory data can study a user’s personal habits. The naïve approach of keeping the user’s identity a secret by hiding / encoding the user’s ID does not work: Frequent user locations, such as the home and office addresses can be found by first self–correlating the user’s trajectory, and then cross–referencing the frequent locations with publicly available spatial data sources, e.g., Yellow Pages, thereby revealing the user’s identity.

     

    In recent years, the study of privacy–preserving data mining has appeared due to the advances in data collection and dissemination technologies which force existing data mining algorithms to be reconsidered from the point of view of privacy protection. Various privacy concepts and measures, such as kanonymity and ldiversity, and related privacy–preservation techniques, such as perturbation, condensation, generalization and data hiding with conceptual reconstruction have been proposed in the general setting. However, their extension or applicability to the spatio–temporal domain, in particular the privacy–preserving data mining of moving object trajectories has not been investigated. Hence the chapter is focused on addressing the unique challenge of obtaining detailed, accurate patterns from anonymized location and trajectory data.

     

    After a thorough status report on research works related to the issue of privacy–preserving data mining on moving object trajectories, first, the chapter proposes a novel anonymization model for preservation of location privacy on moving object trajectories. In this model, users specify their requirements of location privacy, based on the notions of anonymization rectangles and location probabilities, intuitively saying how precisely they want to be located in given areas. Second, the chapter shows a common problem with existing methods that are based on the notion of k–anonymity. This problem allows an adversary to infer a frequently occurring location of a user, e.g., the home address, by correlating several observations. Third, the chapter presents an effective grid–based framework for data collection and mining over the anonymized trajectory data. The framework is based on the notions of anonymization grids and anonymization partitionings which allow effective management of both the user–specified location privacy requirements and the anonymized trajectory data. Along with the framework, three policies for constructing anonymization rectangles, called common regular partitioning, individual regular partitioning, and individual irregular partitioning are presented. All three policies avoid the aforementioned privacy problems of existing methods. Fourth, the chapter presents a client–server architecture for an efficient implementation of the system. A distinguishing feature of the architecture is that anonymization is performed solely on the client, thus removing the need for trusted middleware. Fifth, the chapter presents techniques for solving two basic trajectory data mining operation, namely finding dense spatio–temporal areas and finding frequent routes. The techniques are based on probabilistic counting. Finally, extensive experiments with prototype implementations show the effectiveness of the approach, by comparing the presented solutions to their non–privacy–preserving equivalents. The experiments show that the framework still allows most patterns to be found, even when privacy is preserved.

  • 17.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Kaul, Manohar
    Aarhus University, Department of Computer Science.
    Borgelt, Christian
    European Centre for Soft Computing, Intelligent Data Analysis and Graphical Models Research Unit.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Frequent route based continuous moving object location- and density prediction on road networks2011Ingår i: GIS '11 Proceedings of the 19th ACM SIGSPATIAL International Conference on Advances in Geographic Information Systems / [ed] Isabel F. Cruz and Divyakant Agrawal and Christian S. Jensen and Eyal Ofek and Egemen Tanin, ACM Press, 2011, s. 381-384Konferensbidrag (Refereegranskat)
    Abstract [en]

    Emerging trends in urban mobility have accelerated the need for effective traffic prediction and management systems. The present paper proposes a novel approach to using continuously streaming moving object trajectories for traffic prediction and management. The approach continuously performs three functions for streams of moving object positions in road networks: 1) management of current evolving trajectories, 2) incremental mining of closed frequent routes, and 3) prediction of near-future locations and densities based on 1) and 2). The approach is empirically evaluated on a large real-world data set of moving object trajectories, originating from a fleet of taxis, illustrating that detailed closed frequent routes can be efficiently discovered and used for prediction.

  • 18.
    Gidofalvi, Gyözö
    et al.
    Geomatics ApS - Center for Geoinformatics.
    Larsen, Hans Ravnkjær
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Estimating the Capacity of the Location: Based Advertising Channel2007Ingår i: Conference Proceedings - 6th International Conference on the Management of Mobile Business, ICMB 2007, IEEE Computer Society, 2007, s. 4278546-Konferensbidrag (Refereegranskat)
    Abstract [en]

    Delivering “relevant” advertisements to consumers carrying mobile devices is regarded by many as one of the most promising mobile business opportunities. The relevance of a mobile ad depends on at least two factors: (1) the proximity of the mobile consumer to the product or service being advertised, and (2) the match between the product or service and the interest of the mobile consumer. The interest of the mobile consumer can be either explicit (expressed by the mobile consumer) or implicit (inferred from user characteristics). This paper tries to empirically estimate the capacity of the mobile advertising channel, i.e., the number of relevant ads that can be delivered to mobile consumers. The estimations are based on a simulated mobile consumer population and simulated mobile ads. Both of the simulated data sets are realistic and derived based on real world data sources about population geo–demographics, businesses offering products or services, and related consumer surveys. The estimations take into consideration both the proximity and interest requirements of mobile ads, i.e., ads are only delivered to mobile consumers that are close-by and are interested, where interest is either explicit or implicit. Results show that the capacity of the LBA channel is rather large, which is evidence for a strong business case, but also indicate the need for user–control of the received mobile ads.

  • 19.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics.
    Larsen, Hans Ravnkjær
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Estimating the capacity of the Location-Based Advertising channel2008Ingår i: International Journal of Mobile Communications, ISSN 1470-949X, E-ISSN 1741-5217, Vol. 6, nr 3, s. 357-375Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Delivering ‘relevant’ advertisements to consumers carrying mobile devices is regarded by many as one of the most promising mobile business opportunities. The relevance of a mobile ad depends on at least two factors: (1) the proximity of the mobile consumer to the product or service being advertised, and (2) the match between the product or service and the interest of the mobile consumer. The interest of the mobile consumer can be either explicit (expressed by the mobile consumer) or implicit (inferred from user characteristics). This paper tries to empirically estimate the capacity of the Mobile Advertising channel, i.e. the number of relevant ads that can be delivered to mobile consumers. The estimations are based on a simulated mobile consumer population and simulated mobile ads. Both of the simulated data sets are realistic and derived based on real-world data sources about population geo-demographics, businesses offering products or services, and related consumer surveys. The estimations take into consideration both the proximity and interest requirements of mobile ads, i.e. ads are delivered only to mobile consumers that are close-by and are interested, where interest is either explicit or implicit. Results show that the capacity of the Location-Based Advertising channel is rather large, which is evidence for a strong business case, but it also indicates the need for user-control of the received mobile ads.

  • 20.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Moran, Carlos
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transportvetenskap, Trafik och logistik.
    Estimating Traffic Performance in Road Networks from Anonymized GPS Vehicle Probes2010Ingår i: Proceedings of the Workshop on Movement Research: Are you in the flow?: The 13th AGILE International Conference on Geographic Information Science, 10-14 May 2010, Guimarães, Portugal, 2010, s. 2-Konferensbidrag (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    fulltext
  • 21.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Cab-sharing: An Effective, Door-to-Door, On-Demand Transportation Service2007Ingår i: Proceedings of the 6th European Congress on Intelligent Transport Systems and Services, 18-20 Jun, 2007, Aalborg, Denmark, ERTICO , 2007, s. 8-Konferensbidrag (Refereegranskat)
    Abstract [en]

    City transportation is an increasing problem. Public transportation is cost effective, but do not provide door-to-door transportation. This makes the far more expensive cabs attractive and scarce. This paper proposes a location–based Cab–Sharing Service (CSS), which reduces cab fare costs and effectively utilizes available cabs. The CSS accepts cab requests from mobile devices in the form of origin–destination pairs. Then it automatically groups closeby requests to minimize the cost, utilize cab space, and service cab requests in a timely manner. Simulation–based experiments showthat the CSS can group cab requests in a way that effectively utilizes resources and achieves significant savings, making cab–sharing a new, promising mode of transportation.

    Ladda ner fulltext (pdf)
    fulltext
  • 22.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Mining Long, Sharable Patterns in Trajectories of Moving Objects2006Ingår i: Proceedings of the Third Workshop on Spatio-Temporal Database Management, STDBM 06, September 11, 2006, Seoul, South Korea / [ed] Christophe Claramunt and Ki-Joune Li and Simonas Šaltenis, CEUR , 2006, s. 49-58Konferensbidrag (Refereegranskat)
    Abstract [en]

    The efficient analysis of spatio–temporal data, generated by moving objects, is an es-sential requirement for intelligent locationbased services. Spatio-temporal rules can befound by constructing spatio–temporal baskets, from which traditional association rulemining methods can discover spatio–temporal rules. When the items in the baskets arespatio–temporal identifiers and are derived from trajectories of moving objects, the discovered rules represent frequently travelled routes. For some applications, e.g., an intelligent ridesharing application, these frequent routes are only interesting if they are long and sharable, i.e., can potentially be shared by several users. This paper presents a database projection based method for efficiently extracting such long, sharable requent routes.The method prunes the search space by making use of the minimum length and sharable requirements and avoids the generation of the exponential number of subroutes of long routes. A SQL–based implementation is described, and experiments on real life data show the effectiveness of the method.

  • 23.
    Gidofalvi, Gyözö
    et al.
    Uppsala University, Department of Information Technology.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Mining Long, Sharable Patterns in Trajectories of Moving Objects2009Ingår i: Geoinformatica, ISSN 1384-6175, E-ISSN 1573-7624, Vol. 13, nr 1, s. 27-55Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The efficient analysis of spatio-temporal data, generated by moving objects, is an essential requirement for intelligent location-based services. Spatio-temporal rules can be found by constructing spatio-temporal baskets, from which traditional association rule mining methods can discover spatio-temporal rules. When the items in the baskets are spatio-temporal identifiers and are derived from trajectories of moving objects, the discovered rules represent frequently travelled routes. For some applications, e.g., an intelligent ridesharing application, these frequent routes are only interesting if they are long and sharable, i.e., can potentially be shared by several users. This paper presents a database projection based method for efficiently extracting such long, sharable frequent routes. The method prunes the search space by making use of the minimum length and sharable requirements and avoids the generation of the exponential number of sub-routes of long routes. Considering alternative modelling options for trajectories, leads to the development of two effective variants of the method. SQL-based implementations are described, and extensive experiments on both real life- and large-scale synthetic data show the effectiveness of the method and its variants.

  • 24.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Spatio-temporal Rule Mining: Issues and Techniques2005Ingår i: DATA WAREHOUSING AND KNOWLEDGE DISCOVERY, PROCEEDINGS / [ed] A. Min Tjoa and Juan Trujillo, Springer, 2005, Vol. 3589, s. 275-284Konferensbidrag (Refereegranskat)
    Abstract [en]

    Recent advances in communication and information technology, such as the increasing accuracy of GPS technology and the miniaturization of wireless communication devices pave the road for Location–Based Services (LBS). To achieve high quality for such services, spatio–temporal data mining techniques are needed. In this paper, we describe experiences with spatio–temporal rule mining in a Danish data mining company. First, a number of real world spatio–temporal data sets are described, leading to a taxonomy of spatio–temporal data. Second, the paper describes a general methodology that transforms the spatio–temporal rule mining task to the traditional market basket analysis task and applies it to the described data sets, enabling traditional association rule mining methods to discover spatio–temporal rules for LBS. Finally, unique issues in spatio–temporal rule mining are identified and discussed.

  • 25.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    ST-ACTS: a spatio-temporal activity simulator2006Ingår i: GIS '06 Proceedings of the 14th annual ACM international symposium on Advances in geographic information systems / [ed] Rolf A. de By and Silvia Nittel, ACM Press, 2006, s. 155-162Konferensbidrag (Refereegranskat)
    Abstract [en]

    Creating complex spatio–temporal simulation models is a hot issue in the area of spatio–temporal databases [7]. While existing Moving Object Simulators (MOSs) address different physical aspects of mobility, they neglect the important social and geo–demographical aspects of it. This paper presents ST–ACTS, a Spatio–Temporal ACTivity Simulator that, using various geo–statistical data sources and intuitive principles, models the so far neglected aspects. ST–ACTS considers that (1) objects (representing mobile users) move from one spatio–temporal location to another with the objective of performing a certain activity at the latter location; (2) not all users are equally likely to perform a given activity; (3) certain activities are performed at certain locations and times; and (4) activities exhibit regularities that can be specific to a single user or to groups of users. Experimental results show that ST-ACTS is able to effectively generate realistic spatio–temporal distributions of activities, which make it essential for the development of adequate spatio–temporal data management and data mining techniques.

  • 26.
    Gidofalvi, Gyözö
    et al.
    Geomatic ApS - Center for Geoinformatics.
    Pedersen, Torben Bach
    Aalborg University, Department of Computer Science.
    Risch, Tore
    Uppsala University, Department of Information Technology.
    Zeitler, Erik
    Uppsala University, Department of Information Technology.
    Highly scalable trip grouping for large-scale collective transportation systems2008Ingår i: Advances in Database Technology - EDBT 2008 - 11th International Conference on Extending Database Technology, Proceedings / [ed] Alfons Kemper and Patrick Valduriez and Noureddine Mouaddib and Jens Teubner and Mokrane Bouzeghoub and Volker Markl and Laurent Amsaleg and Ioana Manolescu, ACM Press, 2008, Vol. 261, s. 678-689Konferensbidrag (Refereegranskat)
    Abstract [en]

    Transportation–related problems, like road congestion, parking, and pollution, are increasing in most cities. In order to reduce traffic, recent work has proposed methods for vehicle sharing, for example for sharing cabs by grouping “closeby” cab requests and thus minimizing transportation cost and utilizing cab space. However, the methods published so far do not scale to large data volumes, which is necessary to facilitate large–scale collective transportation systems, e.g., ride–sharing systems for large cities.

    This paper presents highly scalable trip grouping algorithms, which generalize previous techniques and support input rates that can be orders of magnitude larger. The following three contributions make the grouping algorithms scalable. First, the basic grouping algorithm is expressed as a continuous stream query in a data stream management system to allow for a very large flow of requests. Second, following the divide–and–conquer paradigm, four space–partitioning policies for dividing the input data stream into sub–streams are developed and implemented using continuous stream queries. Third, using the partitioning policies, parallel implementations of the grouping algorithm in a parallel computing environment are described. Extensive experimental results show that the parallel implementation using simple adaptive partitioning methods can achieve speed–ups of several orders of magnitude without significantly degrading the quality of the grouping.

  • 27.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Yang, Can
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Scalable Detection of Traffic Congestion from Massive Floating Car Data Streams2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Motivated by the high utility and growing availability of Floating Car Data (FCD) streams for traffic congestion modeling and subsequent traffic congestion-related intelligent traffic management tasks, this paper proposes a grid-based, time-inhomogeneous model and method for the detection of congestion from large FCD streams. Furthermore, the paper proposes a simple but effective, high-level implementation of the method using off-the-shelf relational database technology that can readily be ported to Big Data processing frameworks. Empirical evaluations on millions of real-world taxi trajectories show that 1) the spatio-temporal distribution and clustering of the detected congestions are reasonable and 2) the method and its prototype implementation scale linearly with the input size and the geographical level of detail / spatio-temporal resolution of the model.

  • 28.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik. KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Yang, Can
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    The potential of route based ERS network optimization2020Ingår i: TRA2020 Book of Abstracts: Proceedings of 8th Transport Research Arena TRA 2020, April 27-30, 2020, Helsinki, Finland / [ed] TRA, 2020, s. 1-12, artikel-id 960Konferensbidrag (Refereegranskat)
    Abstract [en]

    The large scale deployment of Electric Road Systems (ERS) is a necessary and viable choice for reaching the emission reduction targets in the road-bound heavy freight sector. The per-kilometer infrastructure development cost of ERS is large, thus selecting segments that yield a high utility is important. According to a newly introduced concept, the electrification utility of a segment in a network is highly dependent on the freight routes-, the powertrain technology-, the energy supply and demand- and the transport loads of the vehicles as well as the topographic aspects- and traffic state of the road network. This paper explains these concepts and aspects and provides first empirical evidence about the potential of route based ERS network optimization that takes these aspects into consideration. Results show that the potential cost savings are up to 75%, which for national expressway networks is estimated to be in the range of 120M€ to 8,520M€.

    Ladda ner fulltext (pdf)
    Potential_of_RENO_ Gidofalvi_TRA2020
  • 29.
    Gidofalvi, Gyözö
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Yang, Can
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    The potential of route based ERS network optimization: Transport demand optimized electric road placement2020Konferensbidrag (Refereegranskat)
    Abstract [en]

    Background

    The large scale deployment of Electric Road Systems (ERS) is a necessary and viable choice for reaching the emission reduction targets in the road-bound heavy freight sector. The per-kilometer infrastructure development cost of ERS is large, thus selecting segments that yield a high utility is important.

    Current methods that utilize freight routes try to optimize the ERS network infrastructure based on the amount of freight routes that include a road segment / link based on select link analysis which, based on network assignment models / assumptions or real data, provides information of where traffic comes from and goes to at selected links, i.e., it provides the spatial distribution and origin–destination (OD) pair composition of aggregate link flows.

    However, as it is suggested in a recent pre-study [1], it is not sufficient to select segments simply based on the number of routes that include the segment or based on the OD-information. In particular, different vehicle-powertrain-onboard and road charging technologies have different energy consumption, energy storage and charging characteristics. The energy consumption and charging characteristics of these vehicle-energy-technology configurations are also heavily affected by the load that they carry as well as the surface and 3D geometry of the roads that they are operated on. Finally, last but not least, as the vehicles have a finite energy storage and an objective to complete maximal part of their routes on electric energy, the electrification utility of segments / links in a network are not independent of one another, but largely depend on which part of the routes include the segments.

    Method

    To take the aforementioned aspects into account, the proposed methodology, adopts the newly introduced concept of Route Based Electrification Utility (RBEU) [1], which can be informally defined as the extra transport work that can be performed in electric operations because of the electrification of the segment in question. Given an infrastructure budget of N segments, to find the N segments that maximizes the electrification utility, the proposed Route based ERS Network Optimization (RENO) method first compresses and indexes the massive input set of vehicle trajectories (routes) and then utilizes this data structure to incrementally add segments to the partial solution that maximize the RBEU of the selection. To take into consideration of vehicle load, speed and road geometries two approaches are proposed: one based on GIS data and simulations and one based on vehicle fuel consumption as a proxy.

    Results and Conclusions

    Empirical evaluations on a real word data set 1) illustrate the superiority of the RENO method over the segment based optimization approach for a wide range of electrification scenarios and 2) analyze the characteristics of the solutions found by the RENO methodology. The potential infrastructure cost savings resulting from RENO are up to 75%, which for national expressway networks is estimated to be in the range of 120M€ (Sweden) to 8,520M€ (China).

    Ladda ner fulltext (pdf)
    fulltext
  • 30.
    Gidófalvi, Gyözö
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Fang, Dong
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    When And Where Next: Individual Mobility Prediction2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    The ability to predict when an individual mobile user will leave his current location and where we will move next enables a myriad of qualitatively different Location-Based Services (LBSes) and applications. To this extent, the present paper proposes a statistical method that explicitly performs these related temporal and spatial prediction tasks in three continuous, sequential phases. In the First phase, the method continuously extracts grid-based staytime statistics from the GPS coordinate stream of the location-aware mobile device of the user. In the second phase, from the grid-based staytime statistics, the method periodically extracts and manages regions that the user frequently visits. Finally, in the third phase, from the stream of region-visits, the method continuously estimates parameters for an inhomogeneous continuous-time Markov model and in a continuous fashion predicts when the user will leave his current region and where he will move next. Empirical evaluations, using a number of long, real world trajectories from the Geo-Life data set, show that the proposed method outperforms a state-of-the-art, rule-based trajectory predictor both in terms of temporal and spatial prediction accuracy.

  • 31.
    Hatzenbühler, Jonas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för trafikforskning, CTR. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Modular Vehicle Routing for Combined Passenger and Freight TransportIngår i: Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The continuous increase in urban deliveries and the ongoing urbanization of large cities require the development of efficient and sustainable transportation solutions. This study investigates the impact of modular vehicle concepts and the consolidation of different demand types in the route planning on the efficiency of the urban freight and passenger transportation system. Modularity is achieved by connecting multiple vehicles together to form a platoon. The consolidation of different demand types is realized by simultaneously consider passenger and freight demand in the optimization algorithm. The considered vehicles are specific for each demand type by can be connected freely, hence it is possible to transport different demand types in the same platoon. The cost terms in the problem formulation are comprised of travel time costs, travel distance costs, fleet size costs, and cost considering unserved requests. The modular vehicle operations are modeled in a novel pickup and delivery problem which is solved using CPLEX and Adaptive Large Neighborhood Search (ALNS). In an extensive scenario study, the potentials of the new modular vehicle type are explored for different spatial and temporal demand distributions. A parameter study on vehicle capacity, vehicle range and cost saving assumptions is performed to study their influence on the efficiency. The experiments carried out indicate a general cost savings of 48% due to modularity and an additional 9% due to consolidation. The reduction mainly stems from reduced operating costs and reduced trip duration, while the same number of requests can be served in all cases. Empty vehicle kilometers are reduced by more than 60% by consolidation and modularity. The proposed model and optimization framework can be used by companies and policy makers to identify required fleet sizes, optimal vehicle routes and cost savings due to different types of operation and vehicle technology.

  • 32.
    Hatzenbühler, Jonas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering. Department of Transport and Planning, Delft University of Technology, Delft, Netherlands.
    Modular vehicle routing for combined passenger and freight transport2023Ingår i: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375, Vol. 173, s. 103688-103688, artikel-id 103688Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study investigates the potential of modular vehicle concepts and consolidation to increasethe efficiency of urban freight and passenger transport. Modularity is achieved by connectingmultiple vehicles together to form a platoon. Consolidation is realized by integrating passengerand freight demand in the routing problem. Vehicles are specific for each demand type but canbe connected freely, allowing the transport of multiple demand types in the same platoon. Therouting problem formulation considers travel time costs, travel distance costs, fleet size costs,and unserved requests costs. The operations are modeled in a novel modular multi-purposepickup and delivery problem (MMP-PDP) which is solved using CPLEX and Adaptive LargeNeighborhood Search (ALNS). In an extensive scenario study, the potential of the modularvehicle type is explored for different spatial and temporal demand distributions. A parameterstudy on vehicle capacity, vehicle range and platoon cost saving is performed to assess theirinfluence on efficiency. The experiments indicate a cost saving of 48% due to modularity and anadditional 9% due to consolidation. The reduction mainly stems from reduced operating costsand reduced trip duration, while the same number of requests can be served in all cases. Emptyvehicle kilometers are reduced by more than 60% by consolidation and modularity. A large-scalecase study in Stockholm highlights the practical applicability of the modular transport system.The proposed model and optimization framework can be used by companies and policy makersto identify required fleet sizes, optimal vehicle routes and cost savings due to different typesof operation and vehicle technology

  • 33.
    Hatzenbühler, Jonas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för trafikforskning, CTR. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Multi-purpose Pickup and Delivery Problem for Combined Passenger and Freight TransportIngår i: Transportation Research Part E: Logistics and Transportation Review, ISSN 1366-5545, E-ISSN 1878-5794Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent developments in modular transport vehicles allow deploying multi-purpose vehicles which can alternately transport different kinds of flows. In this study, we propose a novel variant of the pickup and delivery problem, the multi-purpose pickup and delivery problem, where multi-purpose vehicles are assigned to serve a multi-commodity flow. We solve a series of use case scenarios using an exact optimization algorithm and an adaptive large neighborhood search algorithm. We compare the performance of a multi-purpose vehicle fleet to a mixed single-use vehicle fleet. Our findings suggest that total costs can be reduced by an average of 13% when multi-purpose vehicles are deployed, while at the same time reducing the total vehicle trip duration and total distance travelled by an average of 33% and 16%, respectively. The size of the fleet can be reduced by an average of 35%. The results can be used by practitioners and policymakers to decide on whether the combination of passenger and freight demand flows with multi-purpose vehicles in a given system will yield benefits compared to existing fleet configurations.

  • 34.
    Hatzenbühler, Jonas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för trafikforskning, CTR.
    Multi-purpose pickup and delivery problem for combined passenger and freight transport2024Ingår i: Transportation, ISSN 0049-4488, E-ISSN 1572-9435Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent advances in the development of modular transport vehicles allow deploying multi-purpose vehicles, which enable alternate transport of different demand types. In this study, we propose a novel variant of the pickup and delivery problem, the multi-purpose pickup and delivery problem, where multi-purpose vehicles are assigned to serve a multi-commodity flow. We solve a series of use case scenarios using an exact optimization algorithm and an adaptive large neighborhood search algorithm. We compare the performance of a multi-purpose vehicle fleet to a mixed fleet of single-purpose vehicles. Depending on cost parameters, our findings suggest that in certain scenarios, the total costs can be reduced by an average of 13% when multi-purpose vehicles are deployed, while at the same time reducing total vehicle trip duration and total distance traveled by on average 33% and 16%, respectively. The required fleet size can be reduced by 35% on average when operating multi-purpose vehicles. The results can be used by practitioners and policymakers to determine if the combined service of passenger and freight demand flows with multi-purpose vehicles in a given system will yield benefits compared to existing transport operations.

  • 35.
    Hatzenbühler, Jonas
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Jenelius, Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Cats, Oded
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    Multi-purpose vehicle assignment for combined passenger and freight transport2022Konferensbidrag (Refereegranskat)
    Abstract [en]

    Recent advances in the development of modular transport vehicles allow deploying multi-purpose vehicles, which enable alternate transport of different demand types. In this study, we propose a novel variant of the pickup and delivery problem, the multi-purpose pickup and delivery problem, where multi-purpose vehicles are assigned to serve a multi-commodity flow. We solve a series of use case scenarios using an exact optimization algorithm and an adaptive large neighborhood search algorithm. We compare the performance of a multi-purpose vehicle fleet to a mixed fleet of single-purpose vehicles. Our findings suggest that total costs can be reduced by an average of 13% when multi-purpose vehicles are deployed, while at the same time reducing total vehicle trip duration and total distance travelled by on average 33% and 16%, respectively. The required fleet size can be reduced by 35% on average when operating multi-purpose vehicles. The results can be used by practitioners and policymakers to determine if the combined service of passenger and freight demand flows with multi-purpose vehicles in a given system will yield benefits compared to existing transport operations.

  • 36.
    Hosseini, Reza
    et al.
    Independent Researcher, Tehran 14117-13116, Iran.
    Tong, Daoqin
    Arizona State Univ, Sch Geog Sci & Urban Planning, Tempe, AZ 85287 USA..
    Lim, Samsung
    Univ New South Wales, Sch Civil & Environm Engn, Sydney 2052, Australia.;Univ New South Wales, Kirby Inst, Biosecur Program, Sydney 2052, Australia..
    Sun, Qian Chayn
    RMIT Univ, Sch Sci, Dept Geospatial Sci, Melbourne 3001, Australia..
    Sohn, Gunho
    York Univ, Lassonde Sch Engn, Dept Earth & Space Sci & Engn, 4700 Keele St, Toronto, ON M3J 1P3, Canada..
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Alimohammadi, Abbas
    KN Toosi Univ Technol, Fac Geodesy & Geomat Engn, Dept Geospatial Informat Syst, Tehran 1996715433, Iran..
    Seyedabrishami, Seyedehsan
    Tarbiat Modares Univ, Fac Civil & Environm Engn, Dept Transportat Planning & Engn, Tehran 1411713116, Iran..
    A Novel Method for Extracting and Analyzing the Geometry Properties of the Shortest Pedestrian Paths Focusing on Open Geospatial Data2023Ingår i: ISPRS International Journal of Geo-Information, ISSN 2220-9964, Vol. 12, nr 7, artikel-id 288Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Unlike car navigation, where almost all vehicles can traverse every route, one route might not be optimal or even suitable for all pedestrians. Route geometry information, including tortuosity, twists and turns along roads, junctions, and road slopes, among others, matters a great deal for specific types of pedestrians, particularly those with limited mobility, such as wheelchair users and older adults. Offering practical routing services to these users requires that pedestrian navigation systems provide further information on route geometry. Therefore, this article proposes a novel method for extracting and analyzing the geometry properties of the shortest pedestrian paths, with a focus on open geospatial data across four aspects: (a) similarity, (b) route curviness,

  • 37. Hosseini, S.
    et al.
    Baziyad, H.
    Norouzi, R.
    Jabbedari Khiabani, S.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Albadvi, A.
    Alimohammadi, A.
    Seyedabrishami, S.
    Mapping the intellectual structure of GIS-T field (2008–2019): a dynamic co-word analysis2021Ingår i: Scientometrics, ISSN 0138-9130, E-ISSN 1588-2861, Vol. 126, nr 4, s. 2667-2688Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using geographic information systems (GIS) widely for dealing with transportation problems (is well-known as GIS-T), has made it nessasary for researchers to discover the current state-of-the-art and predict the trends of future research. This paper aims to contribute to a better understanding of GIS-T research area from a longitudinal perspective, over the period 2008–2019. A co-word analysis was used to illustrate all the underlying subfields of GIS-T based on published papers in the Web of Science (WoS) database service. The main knowledge areas representing the intellectual structure of GIS-T including (a) sustainability, (b) health, (c) planning and management, and (d) methods and tools, were detected. Finally, in order to illustrate the structure and development of the identified clusters, two-dimensional maps and strategic diagrams for each period were drawn. This study is the first attempt to employ a text mining method so as to detect the conceptual structure of GIS-T research area from a complex and interdisciplinary literature.

  • 38.
    Joubert, Johan W.
    et al.
    University of Pretoria.
    Trenta, Nadia M.
    University of Pretoria.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik. KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Kordnejad, Behzad
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Transportplanering.
    A matching algorithm to study the evolution of logistics facilities extracted from GPS traces2020Ingår i: Transportation Research Procedia, E-ISSN 2352-1465, Vol. 46, nr 2020, s. 237-244Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ubiquity of anonymous GPS data has opened the door to a promising data source in the field of city logistics modelling. From this data the locations of logistics facilities can be extracted and their evolution studied over time. The minimum edge coverproblem, weighted by the Hausdorff distance, is used as a basis for a matching algorithm to study the location of facilities acrosslongitudinal datasets. The efficacy and validity of the algorithm is assessed through the visual inspection of results in three urbanareas across five time instances. Prevalent errors are unpacked and algorithm modifications suggested. This paper makes amethodological contribution to the handling of GPS data for the purpose of city logistics modelling.

  • 39.
    Khan, Mohd Aiman
    et al.
    KTH.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Jat, C. K.
    Smart Control and Feasibility Analysis of Shared Electric Vehicle Charging Robots2022Ingår i: 2022 IEEE IAS Global Conference on Emerging Technologies, GlobConET 2022, Institute of Electrical and Electronics Engineers (IEEE) , 2022, s. 887-892Konferensbidrag (Refereegranskat)
    Abstract [en]

    Electric Vehicles sales have grown at an exponential rate all over the world. However, this industry still faces many challenges with lack of charging infrastructure being the main problem. This study analyzes the feasibility of mobile electric vehicle charging robots being researched by industry and academia alike and proposes an intelligent control algorithm using deep reinforcement learning algorithms. The algorithm uses Deep Deterministic Policy Gradient based framework and uses an actor-critic and model-free algorithm on the deterministic policy gradient to operate over continuous action spaces. The charging solution is compared with existing conventional solutions using simulations. The results obtained from simulations show that a mobile autonomous charging station can provide many benefits. Apart from having a low upfront investment cost as compared to static chargers, a smart mobile charger also offers greater flexibility. The algorithm also performs better as compared to conventional algorithms like least laxity factor and can easily be adapted to recent trends like shared mobility and autonomous mobility to provide a better user experience.

  • 40.
    Palmberg, Robin C. O.
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Schwertner, Emilia
    Karolinska Institutet, Department of Neurobiology, Division of Clinical Geriatrics, Center for Alzheimer Research, Care Sciences and Society.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Religa, Dorota
    Karolinska Institutet, Department of Neurobiology, Division of Clinical Geriatrics, Center for Alzheimer Research, Care Sciences and Society.
    Susilo, Yusak O.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Using Smart Technologies to Understand Travellers Who have Dementia: Potentials and ChallengesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Age-related cognitive diseases are becoming a growing problem in Sweden. With the fast ageing population and lowered mortality rate comes the spread of cognitive diseases related to dementia. In order to accommodate this growing target group in transport and the built environment, it is crucial to understand the mobility and travel behaviour of patients suffering from these diseases.

    However, the adopted techniques to uncover travel behaviour of today do not allow for errors caused by cognitive impairment, since they require retrospective validation. Such design choices make it hard to understand how to improve the environment to accommodate the target group.  Recently, technologies have emerged that allow for new design methods which can be beneficial for the said target group. This paper aims to address the issue of how to collect and analyse data regarding the mobility of the target group, and roles of the built environment in affecting their behaviour. A literature review has been conducted to 1) uncover the state of the art of the technologies and design methods that relate to automated data collection about the travel behaviour, 2) understand the limits of the user related to software interaction and, in turn, data collection and 3) find possibilities for new solutions to collect travel data from patients who have dementia.

  • 41.
    Palmberg, Robin C. O.
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Susilo, Yusak O.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Developing and Trialling an Implicit Interaction Platform to Monitor Elderly TravellersManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    As the population grows older, age-induced illnesses related to cognitive impairments arise. Little is known regarding what and how the built environment affects that target group. It is theorized that external factors in the built environment might play a part in elderlies getting lost because of conditions related to illnesses such as dementia. To accommodate the target group in a future society, it is crucial to understand any possible correlation between locations and psychophysiological conditions.

    Technological advancements of wearable devices allow for the creation of software that collects data relevant to location as well as biometric data automatically, without affecting the user. By utilising consumer-grade hardware, it is possible to scale up the studies that the software allows for indefinitely.

    This paper covers the development of such a tool, by detailing what has become possible because of previous advancements in research regarding automatic travel diaries and the recognition of psychophysiological conditions through biometric data collection. Initial testing shows, that while data can be collected as proposed, there are drawbacks in terms of run time due to the battery capacity of wearable devices. More data is required to indicate whether the data collected can be used for correlation and causality analysis.

  • 42.
    Palmberg, Robin C. O.
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Susilo, Yusak O.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Naqavi, Fatemeh
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Built Environment Characteristics, Daily Travel, and Biometric Readings: Creation of an Experimental Tool based on a Smartwatch PlatformManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The utilisation of travel surveys can uncover layers of information regarding travel behaviour, travel needs, and more. The collected information is utilised to make strategic planning choices when reorganising or planning new built environments. Over the years, the methods for conducting travel surveys have changed from manual interviews and paper forms to automated travel diaries which are monitoring the trips made by the survey participants. With the fast progression of technological advancements, new possibilities for operationalising said types of automated travel diaries can be changed from utilising mobile devices to wearable devices. Wearable devices are often equipped with sensors which can collect continuous biometric data from sources which are not reachable from standard mobile devices such as smartphones. The biometric data that can be collected through wearable devices ranging from heart rate and blood pressure to temperature and perspiration, given the proper sensors. This advancement opens for new possible layers of information in the collection of travel data. Such biometric data can be used to derive psychophysiological conditions related to cognitive load, which can uncover more in-depth knowledge regarding stress and emotions, given the right variables and sample rate. This paper aims to explore the possibilities in terms of data analysis on a data set collected through a software combining traditional travel survey data, such as position and time, with biometric data, in this case; heartrate, to gain knowledge of the implications of such collected data. The knowledge about the implications of spatial configurations can be used in the planning phase of new areas, in order to create more accessible environments, as the information could be used to make neutral, or even encouraging, environments for travellers.

    Ladda ner fulltext (pdf)
    Built Environment Characteristics, Daily Travel, and Biometric Readings: Creation of an Experimental Tool based on a Smartwatch Platform
  • 43.
    Palmberg, Robin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för trafikforskning, CTR. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Enabling Technologies to Serve the Ageing Urban Society Better (ENTRUST)2018Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    The life span of the inhabitants of Sweden is increasing and with this comes age related cognitive diseases such as those related to dementia. Our society is not prepared to accommodate for the needs of the people who are affected by this.

    The diseases related to dementia often affect the person’s ability to localize themselves and to remember previous and upcoming events. A common issue that occurs is a state called “elopement”.

    Ladda ner fulltext (pdf)
    fulltext
  • 44.
    Palmberg, Robin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Susilo, Y. O.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Naqavi, Fatemeh
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Transport och systemanalys.
    Nybacka, Mikael
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Farkostteknik och Solidmekanik.
    Towards a better understanding of the health impacts of one’s movement in space and time2022Ingår i: Journal of Literature and Science, E-ISSN 1754-646X, s. 1-24Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To better understand the interactions between physical built environment conditions and one’s well-being, we created a passive data collector for travellers and made the first step towards an explanatory model based on psychophysiological relations. By measuring biometric information from select trial participants we showed how different controlled factors are affecting the heart rate of the participants. A regression model with the impact factors such as speed, location, time and activity (accelerometer data) reveals how the factors relate to each other and how they correlate with the recorded individual’s heart rates throughout the observed period. For examples, the results show that the increase in movement speed is not linearly correlated with the heart rate. One’s heart rate would increase significantly when the individual reaches brisk walking and running speed, but not before nor after. Early morning and early evening time slots were the time where the observed individuals have the highest heart rates, which may correlate to individuals’ commute activities. Heart rates at the office would be lower than at home, which might correlate to more physical activities in the household. 

  • 45.
    Palmberg, Robin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för trafikforskning, CTR. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Developing and trialling an implicit interaction platform to monitor and aiding dementia travellers2019Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Age related cognitive diseases are becoming a growing problem in Sweden. With the fast ageing population and lowered mortality rate comes the spread of cognitive diseases related to dementia. In order to accommodate this growing target group in transport and the built environment, it is important to understand the mobility and travel behaviour of patients suffering from these diseases. One subset of this target group is travellers suffering from age induced illnesses related with dementia, which most often have fluctuating symptoms that are affecting the cognitive skills of the traveller. This makes it hard to use standardized forms and survey-based information that would require the traveller to actively respond retroactively, either in oral or written form, since the traveller might have forgotten or mixed up their past experiences, among other things, it becomes very hard to gain confidence in the results as it might be hard to tell in which condition the patient is during the collection.

    We propose an automated collection of biometric data such as heart rate in combination with position. Since the validity of the information collected in this manner is directly related to the quality of the sensors used it means that the precision and accuracy of the results could be virtually endlessly improved by upgrading the hardware and optimizing the software. To take a first step towards a solution like this we have started developing a smart watch application which is utilizing PPG technology to collect heart rate and combine it with positions collected through GPS technology.

    Early testing has shown the possibility to correlate the heart rate of a traveller to their specific location. The implications of this must be validated through data labelling as we wish to utilize machine learning algorithms to analyse the data collected.

    Ladda ner fulltext (pdf)
    Developing and trialling an implicit interaction platform to monitor and aiding dementia travellers
  • 46.
    Palmberg, Robin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi.
    Susilo, Yusak
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Systemanalys och ekonomi. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för transportstudier, CTS. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för trafikforskning, CTR.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Uncovering Effects of Spatial and Transportation Elements on Travellers Using Biometric Data2019Ingår i: TOWARDS HUMAN SCALE CITIES - OPEN AND HAPPY / [ed] Tuuli Toivonen, Karst Geurs, Elias Willberg, Helsinki: Department of Geosciences and Geography, University of Helsinki , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Travel surveys has been used for decades to observe the patterns, locations, and choices, which travellers chose and do during the given observed period. This information can be utilized as background for informed planning decisions. Despite the progress in the travel survey technologies, the applications mostly focus on more traditional travel parameters. With programmable smart watches now, we can also collect real time data that is not solely pertaining to position and travel mode choices, but also to users’ biometric data. Such an application would open another level of possibilities in dynamically integrating land use and transport planning with public health research.

    Utilising a smart watch platform, we are aiming to develop a tool that will collect biometric data, in combination with spatial context, such as position, spatial features and objects in the built environment, and by utilizing machine learning algorithms, try to detect how travellers are affected by their choice of transport mode, the built environment in general as well as how the public transport is operated.

    Early testing reveals the possibility to find correlations between heart rate and position, which in turn could reveal the effect of spatial and transportation elements on the traveller. By targeting widely available hardware, the scalability for this tool is virtually endless, making it possible to collect large amounts of data and utilizing machine learning algorithms to analyse it.

    Ladda ner fulltext (pdf)
    Using Biometric Data to Understand Travellers
  • 47.
    Palmberg, Robin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Susilo, Yusak
    Institute for Transport Studies, Department of Landscape, Spatial, and Infrastructure Sciences, University of Natural Resources and Life Sciences (BOKU).
    Gidófalvi, Győző
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik. KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Naqavi, Fatemeh
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö.
    Built Environment Characteristics, Daily Travel, and Biometric Readings: Creation of an Experimental Tool Based on a Smartwatch Platform2021Ingår i: Sustainability, E-ISSN 2071-1050, Vol. 13, nr 17, artikel-id 9993Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Travel surveys can uncover information regarding travel behaviour, needs, and more. Collected information is utilised to make choices when reorganising or planning built environments. Over the years, methods for conducting travel surveys have changed from interviews and forms to automated travel diaries in order to monitor trips made by travellers. With the fast progression of technological advancements, new possibilities for operationalising such travel diaries can be implemented, changing from utilising mobile to wearable devices. Wearable devices are often equipped with sensors which collect continuous biometric data from sources that are not reachable from standard mobile devices. Data collected through wearable devices range from heart rate and blood pressure to temperature and perspiration. This advancement opens new possible layers of information in the collection of travel data. Such biometric data can be used to derive psychophysiological conditions related to cognitive load, which can uncover in-depth knowledge regarding stress and emotions. This paper aims to explore the possibilities of data analysis on the data collected through a software combining travel survey data, such as position and time, with heartrate, to gain knowledge of the implications of such data. The knowledge about the implications of spatial configurations can be used to create more accessible environments.

    Ladda ner fulltext (pdf)
    Built Environment Characteristics, Daily Travel, and Biometric Readings
  • 48.
    Pernestål, Anna
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Engholm, Albin
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Bemler, Marie
    Scania CV AB, S-15148 Södertälje, Sweden.;Stockholm Sch Econ, House Innovat, S-11383 Stockholm, Sweden..
    Gidofalvi, Gyözö
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    How Will Digitalization Change Road Freight Transport?: Scenarios Tested in Sweden2021Ingår i: Sustainability, E-ISSN 2071-1050, Vol. 13, nr 1, artikel-id 304Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Road freight transport is a key function of modern societies. At the same time, road freight transport accounts for significant emissions. Digitalization, including automation, digitized information, and artificial intelligence, provide opportunities to improve efficiency, reduce costs, and increase service levels in road freight transport. Digitalization may also radically change the business ecosystem in the sector. In this paper, the question, "How will digitalization change the road freight transport landscape?" is addressed by developing four exploratory future scenarios, using Sweden as a case study. The results are based on input from 52 experts. For each of the four scenarios, the impacts on the road freight transport sector are investigated, and opportunities and barriers to achieving a sustainable transportation system in each of the scenarios are discussed. In all scenarios, an increase in vehicle kilometers traveled is predicted, and in three of the four scenarios, significant increases in recycling and urban freight flows are predicted. The scenario development process highlighted how there are important uncertainties in the development of the society that will be highly important for the development of the digitized freight transport landscape. One example is the sustainability paradigm, which was identified as a strategic uncertainty.

  • 49.
    Pernestål, Anna
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Engholm, Albin
    KTH, Skolan för industriell teknik och management (ITM), Centra, Integrated Transport Research Lab, ITRL.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Bemler, Marie
    Scania CV AB.
    Eriksson, Jonas
    CLOSER.
    Will digitalization change freight transport?: Future scenarios for the digitized freight transport landscape with Sweden as a case study2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Digitalization generates many opportunities to improve efficiency and service levels. New technologies include e.g. automation, digitalized information flows, and AI and machine learning. There are several studies on digitalization and automation may affect passenger transport, but the research studies on the effects of digitalization on freight transport are still very limited.

    In the EU, 75% of total freight ton-km are the result of road freight transport (Eurostat 2018). Heavy trucks generate around 17% of the CO2 emissions from all European road transport. The emissions from heavy trucks make up approximately 4% of the total CO2 emissions in the EU (European comission 2016). In Sweden, road freight transport is the dominating mode for domestic transport with almost 90% of the total goods volume being carried by trucks. Only in Stockholm, there are about 100 000 truck deliveries every week. Thus, road freight transport constitutes an important piece in a future sustainable transport system. At the same time, the industry is fragmented and low margin which leads to limited innovation capacity. There is potential for improvement for goods transport, but also barriers that may hinder the development.

    What will happen with road freight transport in the era of digitalization? There are opportunities to increase efficiency by using data. It is also likely that digitalization, including increased e-commerce, will increase transport demand. This contributes with a set of future scenarios for digitalization of the road freight transport sector, including long haulage, city distribution and last mile deliveries to end users. Based on the scenarios the opportunities and barriers to reach a sustainable digitalized transport system are analyzed.

    The scenarios form a platform for academia as well as public and private sector for strategic discussions and decisions. They also form a starting point for identifying knowledge gaps and future research questions. The scenarios are developed by using an explorative scenario development approach, the Intuitive Logic method. This approach is useful in situations when the future development is inherently uncertain and when there is not one determined future. Instead, there are several plausible futures which there is a value to explore in order to be prepared for future events and to improve the understanding of causal processes shaping the future. The work has been performed by an expert group and a smaller analysis team. The expert group involved more than 45 persons from more than 30 organizations, including municipalities, road authorities, vehicle manufacturers (large enterprises as well as start-ups), logistics companies, operators, transport buyers, ICT companies, and research organizations. The expert group met for three workshops, with the themes 1) trend analysis, 2) definition of strategic uncertainties and drafting scenarios, and 3) consequence analysis. The analysis team, consisting of the five authors and two future strategists, has analyzed, refined and condensed the material from the expert group.

    In the work, the most important trends and uncertainties for the development of the digitalized road freight transport landscape are identified. Two strategic uncertainties are selected to form the basis for the scenarios. These axes are 1) whether the private sector or the public sector leads the development, and 2) whether climate actions and sustainability become the top priority on the political agenda and in society in general, or other goals (e.g. welfare, economy, immigration) are more important. These two axes are crossed to form four future scenarios. Examples of aspects that are different in the different scenarios are the development of circular economy, the development and implementation of automation, the structure of infrastructure investments, and the development of customer behavior. In the paper the scenarios are describe in more detail, including a narrative story. The consequences on the road freight transport sector in each scenario are analyzed, including perspectives such as: who are the main actors? What is the impact on business models and value distribution? Does the scenario lead to a sustainable development?

  • 50.
    Prelipcean, Adrian Corneliu
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Mobility Collector: Battery Conscious Mobile Tracking2013Ingår i: Mobile Ghent 2013, 2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Tracking and analyzing the location of users to understand, to predict (and ultimately control) the movement of humans (or animals) has been an important part of research in different groups such as human geographers, urban planers, behavioral scientists or movement ecologists. Despite the availability of tracking technology, the above research activities have been limited by: 1)the spatial granularity of tracking data, 2) the willingness of users to share their private 3) the fact that a tracking mobile application drains a user's battery, and last but not least 4) the absence of a generic, configurable, open-source trajectory collector and annotator. Most studies that exceeded this barrier restrict the collection to settings where an obvious “unlimited” power source is available (i.e., taxi cabs and cars). Thus, to combat the aforementioned limitations, this paper describes the features and design of the Mobility Collector, a configurable, open-source, battery conscious Android mobile tracking application and provides a prototype implementation that works uniformly across multiple hardware devices and Android OS versions.According to the official Android developer's web page [weblink], two main parameters are considered when requesting location updates: minTime, which controls the location update interval and minDistance, which is the minimum distance between location updates. The intended advantage of the method, i.e., battery preserving equitime location sampling, is linked to a degradation of spatial data quality. This approach is relevant for the majority of mapping-oriented applications, which require data that is equally distributed in time, but, in the case of tracking services, an implementation that focuses mostly on equidistance sampling can be vital in order to accurately determine and infer activities while being aware of the user's context.The Mobility Collector provides high quality data in a battery conscious manner. On one hand, the custom implementation of the Location Manager class using a linear movement model based on the recent samples, which duty-cycles the parameters dynamically, allows the data to have a high spatial granularity, making it suitable for different tracking settings (Figure 1, Table 1). On the other hand, the battery life is considerably extended by using a motion-enabled alarm, which switches the servicethat gets location updates on and off, thus allowing for any Android phone to be used for data collection without compromising its usability (Figure 2). While using the Mobility Collector, the usability of a phone is approximately 75% of the daily basis usage plan.The Mobility Collector was designed specifically for research purposes and it offers a high degree of extensibility and usability. First, the source-code will be provided for customization and the platform can be configured either as a standalone client application or as part of a client-server architecture. Second, it provides a configurable user-friendly interface for point- and period-based trajectory annotation. Finally, while the configuration can be done manually by modifying the source-code, a web client that takes configuration-specific parameters (i.e., equitime vs. equidistance sampling, sampling frequency, annotations, etc.) and produces a version of the application according to specific needs is available.

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