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  • 201.
    Albrektsson, Joakim
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Jansson, Robert
    Silfwerbrand, Johan
    CBI .
    Durability of fire exposed concrete cover considering non-linear thermal gradient, boundary effecs and polypropylene fibresManuscript (preprint) (Other academic)
  • 202.
    Alcalá Borao, Raquel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Oxidation of pharmaceuticals by chlorine dioxide in wastewater effluent.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The presence of pharmaceuticals in the environment has raised an emerging interest due to the fact that they pose negative environmental impact and health hazards related to long-term toxicity effects. As conventional treatments are not able to totally remove these substances it is necessary to seek for alternative advanced technologies such as oxidation with chlorine dioxide (ClO2). The objective of this master thesis is thus to find the most optimal dose – reaction time of ClO2 for the oxidation and maximum removal of selected environmentally relevant pharmaceuticals. Factorial design and subsequent optimization with MODDE was selected as the best approach to find the optimal dose – time. Batch oxidation tests were conducted on 100mL aliquots treated with ClO2 using wastewater effluent from Henriksdal WWTP. Thereafter solid phase extraction and final determination of pharmaceuticals was carried out on a high performance liquid chromatography- triple quadrupole mass spectrometry (HPLC-MS/MS). Results showed that applying a dose of 5 mg ClO2/L and a reaction time of 10 minutes, it is possible to remove more than a half of the 17 analyzed substances. Besides most of the pharmaceuticals with high and moderate environmental risk, would pose a low risk for the environment after treatment with the optimal ClO2 dose – reaction time. Despite the fact that ClO2 could successfully degrade most environmentally relevant pharmaceuticals, deeper research concerning the formation of toxic by-products after oxidative treatment needs to be done before upscaling this technology to pilot or full scale as a suitable end of pipe technology for pharmaceuticals removal.

  • 203.
    Alcalá Perales, Diego
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics. UPV.
    Spatial variation in uplift pressure and correlation with rock mass conditions under two buttress dams: A case study of Ramsele and Storfinnforsen dams2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Uplift water pressure is one of the dominating forces with signicant impact acting on a dam. It is usually measured with piezometers installed along the dam. However, the value of the pressure along the dam is often hard to measure due to the limited number of piezometers available (Bernstone et al., 2009). Furthermore, uplift pressure can oscillate substantially in a single hole both with time and also spatially under the dam due to the combination of rock mass characteristics in the foundation, loads and temperature variations.There is still a lack of information regarding the magnitude and variation of the uplift pressure. The aim of this thesis is to investigate the spatial variation of the uplift pressure based on uplift pressure measurements taken from Storfinnforsen and Ramsele dams. The aim is also to investigate how the uplift pressure depends on the rock mass conditions. The two dams Storfinnforsen and Ramsele provides a unique opportunity due to the signicant amount of piezometers, 270 in total, installed along the rock foundation for the new monitoring programme at the monoliths of both dams.Based on the measured uplift pressure, a probabilistic distribution has been assigned to the uplift pressure. In addition, a possible correlation between the rock mass quality and the uplift pressure as well as the joint aperture and the uplift pressure was analysed.

  • 204.
    Aldebe, Wesam
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Tararbit, Yacine
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Tids- och kostnadseffektivisera byggproduktionen: Slöserier och störningar2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The biggest challenge construction companies are facing at the moment is reducing the unnecessary costs and labor as well as to streamline the work. This is a matter and an investigation that has been done multiple times in recent years because this is a major problem in most construction companies. This report is commissioned by Peab for the purpose of identifying wastes and critical disorders, then drafting action proposals to reduce waste of time and costs.

    Four different, completed construction projects have been investigated, commissioned by Peab, and are located in Stockholm. These projects include the reconstruction of a roadway intersection and new construction of pedestrian and cycle tracks. These four projects vary in scale, giving a more varied result compared to four very similar projects

    The gathering of information for this work has mostly included

    lean construction with the various waste in the work industry, as well as the different principles and methods of lean construction, such as Just-In-Time. Other studies on the construction process have also been made, more specifically the production phase, the planning of the work. The difference between value creation time and non-value creation time has been dealt with, as well as risk management and how to conduct a risk analysis.

    Interviews have also been conducted with the aim of identifying the most critical wastes and interferences.

    The gathering of facts from the interviews has been reported in the results.

    It emerged that the four most critical wastes were defects/rework, waiting, transportation and extra processing. In summary, action proposals using lean construction, interviews and the knowledge from this report have been developed to reduce these disturbances and wastages with help of for example Jidoka and PDCA to increase time and cost efficiency in the production process.

    In short, the concept of waste and disturbance can be defined differently. Waste is an activity that does not contribute anything to the business, and a disturbance is a matter of disturbing the work.

  • 205.
    Aldekoa, Joana
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering (moved 20130630).
    Modelling the emerging pollutant di-clofenac with the GREAT-ER model: application to the Llobregat River Basin.2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Water from the Llobregat is used to supply a significant part of the city of Barcelona. At the same time, 60 wastewater treatment plants discharge into this basin. Two field campaigns conducted in the Llobregat Catchment detected more than 80 pharmaceu-ticals in the water. Therefore, it is clear that water quality in Llobregat is a potential concern. A GIS hydrology water quality model has been applied in order to predict the concentrations of one of the pharmaceuticals, diclofenac, in the catchment. Con-sumption, excretion, and degradation data has been studied to calibrate the model. This exercise proves that it is relatively straightforward to predict the concentrations of new and emerging contaminants at basin scale. Nonetheless, the limited and inac-curate available data was a relevant obstacle in this modelling process.

  • 206.
    Aldenlov, Jens
    et al.
    Lulea Univ Technol, Dept Business Adm Technol & Social Sci, S-97187 Lulea, Sweden..
    Bergquist, Bjarne
    Lulea Univ Technol, Dept Business Adm Technol & Social Sci, S-97187 Lulea, Sweden..
    Eriksson, Per-Erik
    Lulea Univ Technol, Dept Business Adm Technol & Social Sci, S-97187 Lulea, Sweden..
    Soderholm, Peter
    Lulea Univ Technol, Dept Business Adm Technol & Social Sci, S-97187 Lulea, Sweden..
    Karrbom Gustavsson, Tina
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Public procurement of railway infrastructure maintenance - a literature review2017In: PROCEEDINGS OF THE 9TH NORDIC CONFERENCE ON CONSTRUCTION ECONOMICS AND ORGANIZATION / [ed] Buser, M Lindahl, G Raisanen, C, POLYTEKNISK FORLAG , 2017, p. 10-21Conference paper (Refereed)
    Abstract [en]

    The maintenance of railway infrastructure has in several instances been changed from government-based to being based on public procurement, with varying degrees of flexibility for the contractor to design their maintenance work. The purpose of-giving contractors a larger freedom of choice of how to perform maintenance is to stimulate them to innovate and develop their maintenance processes. Since the contracts differ in between and there are changes in government policies over time that affects both existing and new contracts, a comparison between different contracts becomes challenging. A literature review has been conducted to understand the change in procurement strategy and how to encourage contractors to innovate. The research questions include: What procurement strategies are there? How is maintenance evaluated? How does procurement affect the innovation opportunities for entrepreneurs? The literature review focuses on railway maintenance and contract design between client and contractor. In total, 17 articles matched the search criteria and were selected for the review. To have successful maintenance service, five articles suggested partnering as a strategy with common goals in combination with good communication during the entirety of the contract. When selecting incentive plan, four articles mentions that a focus on performance-based incentives in combination with risk management is better rather than actual payment schemes. The reason being that payment is often the main cause of conflicts between client and contractor. The scientific literature suggests that improvement in incentives improves quality of maintenance, decreases delays and technical failures. The conclusion from the literature review is that partnering in railway maintenance is considered successful. With accurate knowledge about railway assets the incentive plan becomes accurate which reduces costs. The literature review is a part of a research project with an overall goal to develop a model to guide the selection of appropriate type of procurement strategy, contract and control of maintenance for a more sustainable railway system.

  • 207.
    Alderman, Carin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Andersson, Sophia
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Hydraulic Engineering.
    Cavitation assessment of the Baihetan discharge tunnel – Using Computational Fluid Dynamics2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recently it has become more common in the construction of large dams to reuse diversion tunnels as flood discharge tunnels in the final structure. These tunnels handle large flows with the characteristics of open channel flow. When such large hydrological forces act upon a structure there are several problems to be expected. One of these is the occurrence of cavitation, which could have potential hazardous erosion as a consequence. Cavitation is the formation and collapse of bubbles that create a shockwave strong enough to erode the underlying material.

    The Baihetan dam is one of the largest hydro power projects in China at present. It has three discharge tunnels that all run the risk of developing cavitation damages. By modelling one of the tunnels using Computational Fluid Dynamics (CFD) it is possible to investigate where in the tunnel structure cavitation is likely to occur.

    This degree project assesses the risk of cavitation erosion in the Baihetan tunnel using the static pressure distribution, the velocity distribution and modern cavitation theory. Several modifications of the tunnel – including alterations in the gradient and construction parameters – are simulated in order to investigate if changes in the design can mitigate the cavitation problem. None of the analysed modifications completely eliminate the problem and aeration is recommended to counteract the problem. This study indicates where cavitation might be a problem in the Baihetan tunnel and can be used as a basis for further research.

  • 208.
    Al-Djaber, Jafar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Prestressed glue laminated beams reinforced with steel plates: Comparison between prestressed, reinforced and non-reinforced glue laminated beams according to the Eurocode and the Swedish annex2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The paper presents details of a numerical analysis and simplified construction of strengthened glue laminated beams. Glue laminated beams are strengthened through the use of steel reinforcements embedded between the lamellas of the beams. The study compares the numerical results from reinforced and prestressed beams, simply reinforced beams and non-modified beams. Parametric studies were undertaken to evaluate the effects on reinforcement thickness, beam span, prestressing force and prestressing loss. Modified and prestressed beams with wide spans and large dimensions had a significantly higher design load compared to non-modified beams with similar geometry and span. In the most beneficial cases, a load increase of 438% was observed for point load at midspan and 346% for uniformly distributed load.

  • 209.
    Alekseeva, Iuliia
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Alternative healing in Berlin: nature, arts and science for human recharge2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 210.
    Aleksic, Slobodan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Lin, Max
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Effektivisera implementering av BIM i produktionen: En studie om vad som krävs för att underlätta implementering av digitala verktyg i produktionen2018Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [en]

    The general mode of operation within the building and construction sector in the present days are classified as outdated with plenty of room for improvement. Fortunately, this has been picked up by more organizations and has enabled them to spot the future of the work procedures in digitalisation. This has now been put on the agenda of implementation within the organisations as it has proven to be more efficient not to mention profitable.

    BIM (Building Information Modeling) is today frequently used within projection but the main question remains, the question on “how to implement BIM to the production”. The evolutionary curve within projection is exponentially increasing and at the same time, the vision of a more digital driven production process within the building sector is becoming more of a reality.

    This report is mainly based on field studies in which the building sector often touches the underlying factors on the implementation of digital tools. The focus area lies within the production stage of which many studies show that there is in fact an existence of good knowledge of digitalisation and resources within the branch to apply it to the steamline in order to achieve increased efficiency. However, the process of advancement is being pulled back by the human factor in terms of the individual ́s limited knowledge of digitalisation, the willingness and fear of change and also the generation gap.

    The Final result is based on fact collection, surveys, construction exhibitions and interviews with experienced workers in the targeted field. Study visit has been arranged to SWECO Civil AB and other companies with the similar qualifications. The advantages of implementing digital tools to the day- to-day work are considered to be many. Performing work tasks using for example an ipad will result in a simplified workday in the terms that one will be able to navigate and store required data much more efficiently than before. The process will become less time consuming and with the focus now directed to what is more important, it will result in an improvement of the overall quality. In the long term the aboves mentioned measure is equivalent to a more competitive and profitable organisation.

  • 211.
    Alemu, Beakal Tadesse
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Collocation of Infrastructuresin Stockholm Airport City: Collocation of infrastructures to foster implementation ofnew transportation systems2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 212. Alemu, Belachew Yirsaw
    Expropriation, valuation and compensation practice in Ethiopia: The case of Bahir Dar city and surrounding2013In: Property Management, ISSN 0263-7472, E-ISSN 1758-731X, Vol. 31, no 2, p. 132-158Article in journal (Refereed)
    Abstract [en]

    Purpose: The aim of this paper is to examine the expropriation, valuation and compensation practice. This paper tries to investigate how the expropriation and compensation laws are implemented when privately held land and attached real properties are taken for public purpose development in Bahir Dar city and surrounding. However, further research should be undertaken nation-wide to explore the problems throughout the country. Design/methodology/approach: The paper reports the findings of a survey of expropriatees from main practices throughout Bahir Dar city and its surroundings. Findings: There is a big gap between the actual practice of expropriation, valuation and compensation and the Laws. Lack of application of standardized methods and procedures created situations of unfair valuation and compensation. Practical implications: The practical implication is that the living status of affected people before and after expropriation could be useful. Originality/value: The value of the paper for government officials, real property valuers and investors is that transparency, consistency and fair compensation are useful.

  • 213.
    Alemu, Gulilat
    KTH, School of Architecture and the Built Environment (ABE), Land and Water Resources Engineering, Environmental Management and Assessment.
    GIS based and analytical network process based multi criteria decision aid for sustainable urban form selection of the Stockholm region.2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Decision making processes of natural resources for sustainable development are very complex processes that contain large amounts of contradicting criteria and alternatives and/or objectives. Hence efficiency of planning and decision making is highly dependent on the structure of the decision problems. In this re-spect Multi Criteria Decision Aid (MCDA) is the most widely used method. Particularly GIS-based MCDA using the Analytical Hierarchy Process (AHP) is a well-known method in this respect. However, there are interrelationships and interdependences among problems of the real world. As a result, many spatial problems cannot be structured hierarchally because the importance of the criteria determines the importance of the alternatives, and the importance of the alternatives also determines the importance of the criteria. Analytical Network Process (ANP) based MCDA is a new planning and decision making ap-proach that allows the decision problem to be modeled considering feedbacks and interdependence among criteria. This study critically reviews GIS-based MCDA using the AHP method and the ANP based MCDA method and forwarded recommendations for future works. To attain this, practical decision making processes were used of urban form selection for a sustainable development of the Stockholm region. For this purpose literature was reviewed, separate methodologies were developed, criteria were formulated to be analyzed using GIS and SuperDecision software‟s, and finally reasonable results were achieved and separately presented to critically evaluate both the methods and the outcome. This study showed that GIS has the potential to be an important decision aid tool, that the ANP seems to give more realistic results than the GIS-based MCDA method, and that a compact scenario that over time follows already established polycentric pattern would be the best alternative urban form for a sustainable develop-ment of Greater Stockholm.

  • 214.
    Aletto, Angela
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Engström, Sofia
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Differentialsättningar i höga byggnader mellan vertikalt bärande element av stål och betong: Tidsberoende deformationer i element av betong på grund av lasthistorik, krypning, krympning och elastisk deformation samt elastisk deformation i stålpelare2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When high buildings are built with steel and concrete collaborating, some problems may occur because the materials deform differently. The differences in the final deformations make horizontally casted floors start to lean over time.

    In this study a program has been developed in Mathcad to calculate the final deformations and differences. The differences can then be compensated by casting the floor with a slope. The program is supposed to be used by WSP to project high buildings.

    The program has been used for some parametric studies to show how different parameters can decrease the differences. If this makes the differences small enough it will not even be necessary to cast floors with a slope.

  • 215.
    Alexandrou, Miriam
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Difficulties in FE-modelling of an I-beam subjected to torsion, shear and bending.2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis six different models of IPE240 have been created in order to study their behavior undershear, bending and torsion. These models simulate IPE240 but differ in the boundary conditions, inthe loading and the length of the beam and in some connections which connect certain elements. Inthis study the modeling and simulation of the steel member is executed in ABAQUS Finite ElementAnalysis software with the creation of input files. When developing a model for the finite elementanalysis a typical analysis process is followed. All the parameters that are required to perform theanalysis are defined initially to geometry which is half the beam due to symmetry, and the materialproperties of each model are defined too. Then a mesh is generated for each model, the loads of eachmodel are applied which are expressed as initial displacement. Subsequently, the boundary conditionsfor each model are defined and finally the model is submitted to the solver when the kind of analysishas been defined. Namely, the analysis which is performed in this thesis is static stress analysis.When the ABAQUS has run the models, the contour plots for the von Mises stresses for each modelare studied. In these contour plots, a large concentration of stresses and problems which arise in eachone of the models are notified. As it has been observed in all models, the beam yields at the flangesof the mid-span and collapses at the mid-span. Therefore, the failure at the mid-span is more criticalthan the failure at the support. Moreover, the beams are weak in bending due to the fact that theytwist almost 60-90 degrees under a large initial displacement at the control node. Additionally, much localized failure and buckling occurred at the mid-span, and local concentrated stresses also occurredat the bottom flange at the support due to the boundary conditions details.Thereafter, a verification of the results of the ABAQUS through the simple analytical handcalculations is performed. It is concluded that the error appearing in most selected points is small.However, in some points in the web of the mid-span the error is greater. Additionally, whilecomparing the load-displacement curves of the two different plastic behaviors, it is observed that themodel with an elastic-plastic with a yielding plateau slope behavior has smaller maximum loadresistance than the model with a true stress-strain curve with strain hardening behavior.Finally, some errors and warning messages have occurred during the creation of the input files of themodels and a way of solving them is suggested.

  • 216.
    Alfonsetti, Elisabetta
    et al.
    KTH, School of Electrical Engineering (EES).
    Weeraddana, P. C.
    Fischione, Carlo
    KTH, School of Electrical Engineering (EES), Automatic Control.
    Min-max fair car-parking slot assignment2015In: Proceedings of the WoWMoM 2015: A World of Wireless Mobile and Multimedia Networks, IEEE conference proceedings, 2015Conference paper (Refereed)
    Abstract [en]

    Empirical studies show that cruising for car parking accounts for a non-negligible amount of the daily traffic, especially in central areas of large cities. Therefore, mechanisms for minimizing traffic from cruising directly affect the dynamics of traffic congestions. One way to minimizing cruising traffic is efficient car-parking-slot assignment. Usually, the related design problems are combinatorial and the worst-case complexity of optimal methods grows exponentially with the problem sizes. As a result, almost all existing methods for parking slot assignment are simple and greedy approaches, where each car or the user is assigned a free parking slot, which is closer to its destination. Moreover, no emphasis is placed to optimize any form of fairness among the users as the a social benefit. In this paper, the fairness as a metric for modeling the aggregate social benefit of the users is considered. An algorithm based on Lagrange duality is developed for car-parking-slot assignment. Numerical results illustrate the performance of the proposed algorithm compared to the optimal assignment and a greedy method.

  • 217.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Even more possibilities to combine demand models2011Conference paper (Other academic)
  • 218.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    New models for high speed rail forecasting2011Conference paper (Other academic)
  • 219.
    Algers, Staffan
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301). KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    What is the monetary value of security?2010Conference paper (Other academic)
  • 220.
    Algers, Staffan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Beser Hugosson, Muriel
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Modelling choice of flight and booking class - a study using Stated Preference and Revealed Preference data2001In: International Journal of Services Technology and Management, Vol. 2, no 1/2Article in journal (Refereed)
  • 221.
    Algers, Staffan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301).
    Eliasson, Jonas
    Mattsson, Lars-Göran
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301).
    Is it time to use activity-based urban transport models? A discussion of planning needs and modelling possibilities2005In: The annals of regional science, ISSN 0570-1864, E-ISSN 1432-0592, Vol. 39, no 4, p. 767-789Article in journal (Refereed)
    Abstract [en]

    For some decades now, transport researchers have put considerable efforts into developing what is called activity-based approaches for modelling urban travel demand. The basic idea is that travel demand is derived from people's desires to take part in different activities. In particular, the interrelationships among different activities with respect to temporal and spatial constraints are in focus. It means that such models treat the activities and the travelling of the households with respect to where and when the activities can be carried out and how they may be scheduled, given characteristics of the households and potential opportunities, the transport networks and various institutional constraints. We discuss what demands we see on future travel demand models, with a focus on urban analysis. This discussion is somewhat biased towards what role activity-based models could play in meeting these demands. We then review in some detail three prominent and distinctly different representatives of operational activity-based models to give an indication of what new modelling possibilities they offer. Theoretical appeal, empirical validity, usefulness for planning, need for data and easiness of implementation are discussed. In the final section we draw some conclusions about the prospects of these models and of their descendants.

  • 222.
    Algers, Staffan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301). KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Mattsson, Lars-Göran
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301). KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Rydergren, Clas
    Östlund, Bo
    Sampers: erfarenheter och utvecklingsmöjligheter på kort och lång sikt2009Report (Other academic)
  • 223.
    Algers, Staffan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis.
    Petz, M.
    Embedded parks in Quiet Zones2012In: 41st International Congress and Exposition on Noise Control Engineering 2012, INTER-NOISE 2012: Volume 4, 2012, 2012, p. 3024-3035Conference paper (Refereed)
    Abstract [en]

    One of the targets of the European project "CityHush Acoustically Green Road Vehicles and City Areas" under the 7th Framework Program is to support city administrations to eliminate harmful effects of noise exposure and decrease levels of transport noise, especially in urban areas. A particular attention has been paid to investigating boundary conditions and maximum noise gains especially for parks embedded in Q-zones where only quiet low emission vehicles are tolerated. Other vehicles are banned or subject to a noise fee for entering the quiet zone. Within the CityHush project existing noise levels in different parks of European cities were determined and the influence of local parameters on the noise situation, such as size of a Qzone, was investigated. Moreover a variation of noise fees and traffic restrictions as well as different percentages of low noise vehicle ownerships inside the Q-zone and outside (countrywide) was evaluated. Based on different noise and annoyance criteria possibilities and limits to reduce noise in the city environment will be shown, based on studies carried out for 5 European cities.

  • 224.
    Algers, Staffan
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301).
    Sundbergh, P.
    Byström, C.
    Valuation of road traffic noise profiles2009In: 38th International Congress and Exposition on Noise Control Engineering 2009, INTER-NOISE 2009, 2009, p. 2161-2168Conference paper (Refereed)
    Abstract [en]

    Swedish noise values are today based on a study concerning hedonic price values. The valuation of the average noise levels assumes that there is no difference between different noise profiles, i.e. how the noise level varies throughout the day. In order to be able to take appropriate measures towards noise problems, it is important to know to what extent the noise profile matters. The project aims at researching how the noise value depends on the road traffic noise profile. It further aims at studying how values are affected by the type of activity in which the noise disturbance occurs (being out in the garden/try to sleep in the bedroom). Our method is to use stated preference techniques (pair wise choices) to elicit noise profile values. Respondents listen to and evaluate noise profile where we vary the level of background noise, frequency of noise events and the noise level of the events. This paper also discusses possibilities to estimate willingness to pay for changes in different components of noise profiles.

  • 225.
    Al-Haddad, Hussein
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Amin, Hamad
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Solceller – Solen är ju gratis!: En undersökning av huruvida solceller är ett fördelaktigt energisystem med avseende på tekniska och ekonomiska aspekter2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report is a result of a bachelor thesis at the school of Architecture and the Built environment (corresponding to 15 HP) and is written during spring 2012 at the Royal Institute of Technology (KTH) in Stockholm. The Bachelor's essay is based on the design and dimensioning of a house which is located at a predetermined site in Malmo, Sweden.

    The idea is to construct a house that is appropriate to use for an average Swedish family of four family members. The house is designed in a modern way with respect to ease of access and disabled facilities. The installation that have been considered are heating, ventilation, sanitation and electricity. Construction calculations and material selection are also discussed.

    Furthermore, a study about photovoltaic cells has been done. The purpose of the study is to decide whether photovoltaic cells are an advantageous energy system to the house with respect to economical and technical aspects. The result of the study shows that solar cells has an efficiency of 14% and gives a surplus of electricity during the summer, the cells gives more than half the need of electricity during the spring. However, the production of electricity is low during autumn and winter.

    The system of the photovoltaic cells is fairly easy to install, and dose not require maintenance, however the system is expensive because the cost of investment is more than 227 000 kr. The annual saving is about 6700 kr but the investment will be profitable only after 18 years.

  • 226.
    Alhakim, Ali
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hakim, Roz
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Inneklimat i kontorsmiljö: Utvärdering av inneklimat i en kontorsmiljö med fokus på ventilationen2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today's society, humans spend about 90 percent of their time indoors, in an artificial indoor climate. As people tend to be indoors more and more, it is important that the ventilation work as well and efficiently as possible, and that the indoor climate is pleasing for our well-being at the workplace. Previous studies show that almost half of Swedes are dissatisfied with the ventilation in their work environment (offices).

    A good indoor climate in offices increases employee satisfaction, increases productivity, and reduces absenteeism. This causes the organization / company to save money in the end, as staff work more efficiently and have less sick leave.

    The purpose of this study is to investigate the climate in office environment, focusing on thermal comfort and to see how ventilation systems affect the indoor climate. Furthermore, the relationships between these will be analyzed. The aim is to investigate how the comfort in the office affects human health, productivity and well-being. The goal is also to identify if there is insufficient ventilation to the offices that will be investigated and to eventually present possible improvements.

    In this report a study of six offices on Brinellvägen 23 was carried out. In the study, a number of flow measurements are carried out for each office's supply and exhaust air, carbon dioxide measurements, temperature and the relative humidity for four hours in four of the offices, with open and closed doors. While in two of the offices, the measurements continued for a whole working day, 6-8h.

    In addition to these measurements, surveys were distributed to the staff in the offices in order to share subjective opinions about the environment in the offices.

    The results from the measurements and the survey showed that the overall climate was not satisfactory, and discomfort was experienced by the people working there. Only one office met the projected supply airflow, while the remaining offices neither met the projected flows nor BBR requirements for the amount of flow in office environments. The carbon dioxide levels in the offices with one person was acceptable, they did not pass the limit of 1000 ppm. However, the offices were projected for two persons and when two persons worked in the offices, the carbon dioxide levels exceeded about 1200 ppm. When the carbon dioxide level exceeds 1000 ppm, it is recommended that the ventilation be checked, as needed in this case.

  • 227. Alhasan, Ilyas
    et al.
    Matthews, Brian
    Towner, Jeremy
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, System Analysis and Economics.
    Evaluation of intercounty integrated ticketing scheme, the case of Movingo in Sweden2019Conference paper (Refereed)
  • 228. Alhasawi, Anas
    et al.
    Heng, Piseth
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. Université Européenne de Bretagne, France.
    Hjiaj, Mohammed
    Guezouli, Samy
    Battini, Jean-Marc
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Co-rotational planar beam element with generalized elasto-plastic hinges2017In: Engineering structures, ISSN 0141-0296, E-ISSN 1873-7323, Vol. 151, p. 188-205Article in journal (Refereed)
    Abstract [en]

    Slender elements in framed structures may undergo large displacement and experience highly nonlinear behavior. This paper presents a two-node co-rotational flexible beam with generalized elasto-plastic hinges at the beam ends. A Condensation procedure is used to remove the internal degrees of freedom so that the formulation is easily incorporated with the standard co-rotational approach. A family of asymmetric and convex yield surfaces of super-elliptic shape is considered for the plastic behavior of the hinges. By varying the roundness factor, an infinite number of yield surfaces are obtained making it possible to select the yield function that best fit experimental data of any type of cross-section and material. The nonlinear response of bolted connections subjected to both bending and axial forces are conveniently modeled with such a yield surface. Discrete constitutive equations for the hinge plastic deformations are derived using the implicit scheme for both smooth and non-smooth cases. Numerical examples demonstrate the accuracy of the model in predicting the large displacement inelastic response of framed structures. Effect of the roundness factor on the ultimate load strongly depends on the structure typology. It was observed that cyclic loading produces pinching effect, cyclic softening and ductile behavior. Those effects are more pronounced with anisotropic yield criteria.

  • 229.
    Ali Akbar, Saman
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Al-Naddaf, Manar
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Evaluating and Comparing of Three Penetrability Measuring Devices: Modified Filter Pump, Modified Penetrability Meter, and Short Slot2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Rock grouting is a commonly used process for sealing rocks in tunnels to reduce water ingress. In order to achieve sufficient sealing level the grout must effectively penetrate into rock fractures while the limiting factor is filtration of cement based grout. Many devices and measuring methods have been developed to study filtration and to measure the penetrability. The filter pump and the penetrability meter are two of the most commonly used instruments for measuring filtration tendency in the field and in the lab, while short slot is used mainly in the lab. The results obtained from these devices have relatively different estimations of the penetrability partly due to the weaknesses in measuring methods and test procedures. Furthermore, there are no clear criteria to find out which of the results are closer to the reality or how much the results differ among these instruments. The aim of this study is comparing, and evaluating the results of these devices in relatively similar conditions while using more accurate methods of weight-time and pressure-time compared to the less reliable total volume method. The filter pump and the penetrability meter were modified In order to fulfill the requirement of testing in similar conditions and to improve their accuracy and versatility.

    The results show that increasing the pressure improves the penetrability significantly. The modification of the filter pump results in reducing many uncertainties related to the testing procedure. Probably the modified filter pump has higher accuracy in measuring the penetrability compared to regular filter pump. The short slot has the highest accuracy in estimating penetrability of cement based grout especially at higher pressures, furthermore, the short slot provides a more flexible way to measure penetrability with different pressures in the range of 1-15 bars.

  • 230.
    Ali, Hussam Jader
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Manta, Teofil
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    En utvärdering av ett nyutvecklat betongbjälklag för fler bostadshus2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The development of apartment buildings puts high demands on the technical characteristics of

    floor systems. The lattice girder system which today represents the most commonly utilized

    floor system when building apartment buildings, is characterized by a good load-bearing

    ability along with great opportunities from a technical point of view.

    The aim of this analysis was to compare the traditional lattice girder system with a newly

    developed floor system based on hollow core slabs. The comparison is based on the current

    technical requirements set by Boverkets byggregler (BBR) and has its main focus on subjects

    related to sound, fire and moisture matters. The comparison has also accounted for the

    maximum spans which can be used for each solution respectively.

    The results of the investigation show that the newly developed floor system is competitive

    enough to be used in future apartment buildings. While the advantages of the lattice girder

    system are distinctive from a sound point of view, the utilization of the newly developed floor

    solution enables longer spans and shorter curing time.

  • 231.
    Alias, Klara
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Mabrouk, Nour
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Val av uppvärmningssystem för ett småhus: – fjärrvärme, bergvärme eller elvärme2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When choosing a heating system for a house you have to weigh the various pros and cons to each other, because no system is perfect or flawless. Which heating system that may be of interest depends on your preference and needs, housing characteristics, actual conditions and also the budget that exists.

    In this thesis district heating, geothermal heating and electric heating will be considered when selecting heating system for a house. The choice will be based on decisions as economy, convenience and environmental impact. It is important to thoroughly consider the building and its function before making a decision of a heating system. A house is examined as a case study to connect to this thesis.

    In connection with the comparisons, a analysis of financial, convenience and environmental impact will be examined for each heating system to in this way reach a final result and conclusion.

  • 232.
    Alinder, Martin
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Banking and Finance.
    Finansinspektionens regelverk för ersättningssystem inom finansbranschen: En granskande studie av regleringens effekter på den finansiella industrin2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att det finns ett tydligt samband mellan ersättningssystems utformning och de anställda och ledningens beteende är sedan länge känt. I efterdyningarna av den senaste finanskrisen har det funnits stort medialt fokus på de enorma bonusar som betalats ut till anställda på banker som sedan tvingats söka statligt stöd.

    För att både minska de risker som är förknippade med vissa typer av rörliga ersättningssystem och för att tillgodose den allmänna opinionen har EU valt att inkludera reglering av rörlig ersättning som en del av regleringen av finansiell verksamhet. Detta beslut resulterade för den svenska marknadens del i regelverket FFFS 2009:6 där Finansinspektionen redogjorde för föreskrifter och allmänna råd gällande rörlig ersättning i finansiella företag. För att tillgodose de uppdaterade EU-direktiven utformades en uppdaterad version av regelverket, FFFS 2011:1, som är ett bindande regelverk i form av endast föreskrifter.

    Reaktionerna från finansbranschen har till stora delar varit negativa. Många anser att regleringen är ett spel för galleriet med en väldigt liten reell verkan på att stävja företagens risktagande och öka den finansiella stabiliteten. Politiker, makthavare och allmänheten är dock rörande överens om att förändringar inom företagens rörliga ersättningssystem måste ske för att främja en långsiktigt hållbar utveckling och undvika kostsamma statliga räddningspaket till systemviktiga institutioner i kristider.

    I denna uppsats redogör vi för teorier bakom de finansiella risker som rörliga ersättningssystem utgör. Vidare beskriver vi bakgrunden till föreskrifterna för rörlig ersättning på både nationell och internationell nivå och redogör för regelverkets utformning. Slutligen presenterar vi tankar från berörda företag som vi intervjuat och analyserar effekterna av regleringen.

    De totala effekterna av regleringen är än så länge oklara men redan nu kan vi se förändringar i företags ersättningssystem i form av ökad fast ersättning samt förändringar i ersättningspolicys med ett ökat fokus på ickefinansiella kriterier. De praktiska effekterna för branschens arbetssätt är dock ytterst diffusa och vi ställer oss frågande till hur gynnsamma dessa nya regler kommer vara för den svenska marknaden på sikt.

  • 233.
    Aliu, Jeton
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Youkhanis, Ledia
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Energieffektivisering genom ombyggnad: Med hjälp av VIP-Energy2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project has been written in collaboration with Värmex AB, with the generous help of Anders Ericsson as our fellow adviser and Peter Hansson (Sweco) our mentor from the Royal institute of technology located in Haninge.  

    Today we find questions pertaining to energy consumption in apartment blocks of real significance; with each building project a declaration that shows the amount of energy consumed is of outmost importance. We strive to reduce energy consumption in apartment blocks by 50 % until year 2050. In this degree thesis, we aim to describe measures and solutions to lower the consumption of energy in a specific apartment block located in Nacka, Stockholm.  

    This building has been standing quite untouched and unmarked since 1949, yet it is still in compliance with the demands stated by BBR concerning energy efficiency, in large because of its climate shell. Sources show that greater parts of its outer shell for example the front, should have been repaired during the first 30 years, and the matter is still to be solved.

    The use of a computer software VIP-Energy has enabled us to state a hypothesis. With the help of public documents from Housing And Urban Development Town Building Office (HUD) giving us an overview of the different dimensions of the building, we've been able to plot all this data into the software. Information such as building materials, location, heating systems have also been necessary in our analysis. Results are automatically compared to the demands required by BBR. It is through experimentation of this data that we have been successful in collecting our results. 

    In the analysis, we chose to focus on the climate shell that constitutes: roof, floors, walls, windows and doors. Our results show that lower U-values conduce better energy efficiency.

    Studies show that almost 35 % of energy loss in a building is caused by the windows of the building, this this is consistent with the building which this analysis is based on.

    We have solved this by changing sheet glass that is energy efficient. We also aim to change the frame and seams surrounding the windows, in order to lower transmission losses and possible draughts in the apartments. This will result in hopefully a higher degree of comfort and refreshing atmosphere. The same changes apply to entry doors in order to keep energy loss to a minimum. Also an external insulation in the outer wall contributes to improvements on u-value and use.

     The original building shows an average U-value of 0,656W/m2K and the energy consumption is 96 kWh/m2 per year. According to BBR, older buildings should have a U-value of 0,400W/m2K and an energy consumption of 90kWh/m2 per year. Energy balance calculation show new values for the building were the u -value should be set to 0,409W/m2K, and energy consumption should be set to 64kWh/m2.

  • 234.
    Alizadeh Amirbeigi, Sara
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    A study of optimizing the Processing time for Building permits: Study Case: Tyresö municipality2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are rules in urban development and the construction industry, which encourages organizations to work according to standards and approved codes. For example: it is required by law for all property owners to apply and obtain a permit in order to carry out an action in construction building. Often, the permit process takes a great deal of time to process.

     

    Currently, there is a lack of constructional project for residential buildings in Stockholm region, and there is critique toward the municipalities for having a long processing time for reviewing building permits. This study is about ways to optimize the processing time for building permits. As a first step, it was important to study parameters, which maximizes the quality and efficiency. Since, time is often one of the restricted factors in urban development, optimizing the processing time issuing a construction permit can be one of the quality elements in service oriented business organizations like a municipality.

     

    This study aims to analyze the building permit processing time, and investigate different factors that have influence on it. The case for this was Tyresö municipality, a municipality with approximately 45 000 inhabitants in the south east of the Stockholm region. Required information has been developed based on interviews with the municipality's personnel and professional construction developer who have applied for building permit in Tyresö region. In addition, previous reports, statistics, and cases from the municipality archive have been used to identify important concepts as empirical material.

     

    Long processing time is a current existing problem in many municipalities. A service oriented organization like a municipality should try to increase clients’ satisfaction by a continual and proper communication with public. The municipality can identify the costumer needs and expectations and improve the quality efficiency by communication. Optimizing of processing time in the building permit cases is one of the issues of process optimization that can increase customer satisfaction. Using Total Quality Management strategy in the organization, help the municipality to optimize the processing time continuously. It means quality improvement and leads to long term costumer satisfaction. Since functional team develops solutions to problems in TQM style it often shortens the time taken to produce services. The focus of this management style is on importance of the relationship between costumer and organization and it is directly linked to their communication.

     

    By service guarantee as a tool, municipality which is a politically governed organization makes assurance for public as its costumer to provide community services with proper quality. A well defined service Guarantee has been contributed the improving quality of the services. It helps the planning and building department of municipality to increase the costumer satisfaction and attract more building developer to invest in the municipality region.

  • 235.
    Alizadeh Khameneh, Mohammad Amin
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    On Optimisation and Design of Geodetic Networks2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Optimisation of a geodetic network is performed to provide its pre-set quality requirements. Today, this procedure is almost run with the aid of developed analytical approaches, where the human intervention in the process cycle is limited to defining the criteria. The existing complication of optimisation problem was terminated by classifying it into several stages. By performing these steps, we aim to design a network with the best datum, configuration and the observation weights, which meets the precision, reliability and cost criteria.

    In this thesis, which is a compilation of four papers in scientific journals, we investigate the optimisation problem by developing some new methods in simulated and real applications.

    On the first attempt, the impact of different constraints in using a bi-objective optimisation model is investigated in a simulated network. It is particularly prevalent among surveyors to encounter inconsistencies between the controlling constraints, such as precision, reliability and cost. To overcome this issue in optimisation, one can develop bi-objective or multi-objective models, where more criteria are considered in the object function. We found out that despite restricting the bi-objective model with precision and reliability constraints in this study, there is no significant difference in results compared to the unconstrained model. Nevertheless, the constrained models have strict controls on the precision of net points and observation reliabilities.

    The importance of optimisation techniques in optimal design of displacement monitoring networks leads to the development of a new idea, where all the observations of two epochs are considered in the optimisation procedure. Traditionally, an observation plan is designed for a displacement network and repeated for the second epoch. In the alternative method, by using the Gauss-Helmert method, the variances of all observations are estimated instead of their weights to perform the optimisation. This method delivers two observation plans for the two epochs and provides the same displacement precision as the former approach, while it totally removes more observations from the plan.

    To optimise a displacement monitoring network by considering a sensitivity criterion as a main factor in defining the capacity of a network in detecting displacements, a real case study is chosen. A GPS displacement monitoring network is established in the Lilla Edet municipality in the southwest of Sweden to investigate possible landslides. We optimised the existing monitoring network by considering all quality criteria, i.e. precision, reliability and cost to enable the network for detecting 5 mm displacement at the net points. The different optimisation models are performed on the network by assuming single baseline observations in each measurement session. A decrease of 17% in the number of observed baselines is yielded by the multi-objective model. The observation plan with fewer baselines saves cost, time and effort on the project, while it provides the demanded quality requirements.

    The Lilla Edet monitoring network is also used to investigate the idea, where we assume more precise instruments in the second of two sequential epochs. In this study, we use a single-objective model of precision, and constrained it to reliability. The precision criterion is defined such that it provides the sensitivity of the network in detecting displacements and has a better variance-covariance matrix than at the first epoch. As the observations are GPS baselines, we assumed longer observation time in the second epoch to obtain higher precision. The results show that improving the observation precision in the second epoch yields an observation plan with less number of baselines in that epoch. In other words, separate observation plans with different configurations are designed for the monitoring network, considering better observation precision for the latter epoch.

  • 236.
    Alizadeh Khameneh, Mohammad Amin
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. WSP Civils, Department of Geographic Information and Asset Management, Stockholm, Sweden.
    Optimal Design in Geodetic GNSS-based Networks2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    An optimal design of a geodetic network helps the surveying engineers maximise the efficiency of the network. A number of pre-defined quality requirements, i.e. precision, reliability, and cost, of the network are fulfilled by performing an optimisation procedure. Today, this is almost always accomplished by implementing analytical solutions, where the human intervention in the process cycle is limited to defining the requirements. Nevertheless, a trial and error method can be beneficial to some applications. In order to analytically solve an optimisation problem, it can be classified to different orders, where an optimal datum, configuration, and optimal observation weights can be sought such that the precision, reliability and cost criteria are satisfied.

    In this thesis, which is a compilation of six peer-reviewed papers, we optimised and redesigned a number of GNSS-based monitoring networks in Sweden by developing new methodologies. In addition, optimal design and efficiency of total station establishment with RTK-GNSS is investigated in this research.

    Sensitivity of a network in detecting displacements is of importance for monitoring purposes. In the first paper, a precision criterion was defined to enable a GNSS-based monitoring network to detect 5 mm displacements at each network point. Developing an optimisation model by considering this precision criterion, reliability and cost yielded a decrease of 17% in the number of observed single baselines implying a reliable and precise network at lower cost. The second paper concerned a case, where the precision of observations could be improved in forthcoming measurements. Thus a new precision criterion was developed to consider this assumption. A significant change was seen in the optimised design of the network for subsequent measurements. As yet, the weight of single baselines was subject to optimisation, while in the third paper, the effect of mathematical correlations between GNSS baselines was considered in the optimisation. Hence, the sessions of observations, including more than two receivers, were optimised. Four out of ten sessions with three simultaneous operating receivers were eliminated in a monitoring network with designed displacement detection of 5 mm. The sixth paper was the last one dealing with optimisation of GNSS networks. The area of interest was divided into a number of three-dimensional elements and the precision of deformation parameters was used in developing a precision criterion. This criterion enabled the network to detect displacements of 3 mm at each point.

    A total station can be set up in the field by different methods, e.g. free station or setup over a known point. A real-time updated free station method uses RTK-GNSS to determine the coordinates and orientation of a total station. The efficiency of this method in height determination was investigated in the fourth paper. The research produced promising results suggesting using the method as an alternative to traditional levelling under some conditions. Moreover, an optimal location for the total station in free station establishment was studied in the fifth paper. It was numerically shown that the height component has no significant effect on the optimal localisation.

  • 237.
    Alizadeh Khameneh, Mohammad Amin
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Optimization of Lilla Edet Land Slide GPS Monitoring Network2014Conference paper (Other academic)
  • 238.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning. WSP Civils, Department of Geographic Information and Asset Management.
    Eshagh, Mehdi
    University West, Department of Engineering Science.
    Jensen, Anna B. O.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Geodesy and Satellite Positioning.
    Optimization of Deformation Monitoring Networks using Finite Element Strain Analysis2018In: Journal of Applied Geodesy, ISSN 1862-9016, E-ISSN 1862-9024, Vol. 12, no 2Article in journal (Refereed)
    Abstract [en]

    An optimal design of a geodetic network can fulfill the requested precision and reliability of the network, and decrease the expenses of its execution by removing unnecessary observations. The role of an optimal design is highlighted in deformation monitoring network due to the repeatability of these networks. The core design problem is how to define precision and reliability criteria. This paper proposes a solution, where the precision criterion is defined based on the precision of deformation parameters, i.e. precision of strain and differential rotations. A strain analysis can be performed to obtain some information about the possible deformation of a deformable object. In this study, we split an area into a number of three-dimensional finite elements with the help of the Delaunay triangulation and performed the strain analysis on each element. According to the obtained precision of deformation parameters in each element, the precision criterion of displacement detection at each network point is then determined. The developed criterion is implemented to optimize the observations from the Global Positioning System (GPS) in Skåne monitoring network in Sweden. The network was established in 1989 and straddled the Tornquist zone, which is one of the most active faults in southern Sweden. The numerical results show that 17 out of all 21 possible GPS baseline observations are sufficient to detect minimum 3 mm displacement at each network point.

  • 239.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Eshagh, Mehdi
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. University West, Division of Surveying Engineering.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Optimisation of Lilla Edet Landslide GPS Monitoring Network2015In: Journal of Geodetic Science, ISSN 2081-9919, E-ISSN 2081-9943, Vol. 5, no 1, p. 57-66Article in journal (Refereed)
    Abstract [en]

    Since the year 2000, some periodic investigations have been performed in the Lilla Edet region to monitor and possibly determine the landslide of the area with the GPS measurements. The responsible consultant has conducted this project by setting up some stable stations for GPS receivers in the risky areas of Lilla Edet and measured the independent baselines amongst the stations according to their observation plan. Here, we optimise the existing surveying network and determine the optimal configuration of the observation plan based on different criteria. We aim to optimise the current network to become sensitive to detect 5 mm possible displacements in each net point. The network quality criteria of precision, reliability and cost are used as object functions to perform single-, bi- and multi-objective optimisation models. It has been shown in the results that the single-objective model of reliability, which is constrained to the precision, provides much higher precision than the defined criterion by preserving almost all of the observations. However, in this study, the multi-objective model can fulfil all the mentioned quality criteria of the network by 17% less measurements than the original observation plan, meaning 17% of saving time, cost and effort in the project.

  • 240.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Eshagh, Mehdi
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. Department of Engineering Science, University West, Trollhättan, Sweden.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    The Effect of Instrumental Precision on Optimisation of Displacement Monitoring Networks2016In: Acta Geodaetica et Geophysica, ISSN 2213-5820, Vol. 51, no 4, p. 761-772Article in journal (Refereed)
    Abstract [en]

    In order to detect the geo-hazards, different deformation monitoring networks are usually established. It is of importance to design an optimal monitoring network to fulfil the requested precision and reliability of the network. Generally, the same observation plan is considered during different time intervals (epochs of observation). Here, we investigate the case that instrumental improvements in sense of precision are used in two successive epochs. As a case study, we perform the optimisation procedure on a GPS monitoring network around the Lilla Edet village in the southwest of Sweden. The network was designed for studying possible displacements caused by landslides. The numerical results show that the optimisation procedure yields an observation plan with significantly fewer baselines in the latter epoch, which leads to saving time and cost in the project. The precision improvement in the second epoch is tested in several steps for the Lilla Edet network. For instance, assuming two times better observation precision in the second epoch decreases the number of baselines from 215 in the first epoch to 143 in the second one.

  • 241.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Eshagh, Mehdi
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. University West, Department of Engineering Science.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    The Effect of Instrumental Precision on Optimisation of Epoch-Wise Displacement Networks2015Conference paper (Other academic)
  • 242.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. WSP Civils, Department of Geographic Information and Asset Management.
    Horemuž, Milan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Jensen, Anna B. O.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Vium Andersson, Johan
    WSP Civils, Department of Geographic Information and Asset Management.
    Optimal Vertical Placement of Total Station2018In: Journal of Surveying Engineering, ISSN 0733-9453, E-ISSN 1943-5428Article in journal (Refereed)
    Abstract [en]

    When using the free station method, a Total Station (TS) is established by performing distance and angle observations toward a number of Control Points (CPs). The quality of the establishment is crucial for the quality of subsequent measurements. The optimal horizontal location of the TS has been investigated in previous studies. Even the vertical precision is important in many applications, especially with significant height variations. Therefore in this paper, we focus on the optimality of vertical location of the TS. As an optimality criterion, the sum of TS coordinates and orientation variances is used. To investigate the optimization problem, an analytical as well as a trial and error method is developed. Both methods showed that the height component has no significant influence on the optimal vertical placement of the TS. Inspection of results from the trial and error method, where the CPs are moved in different height layers, indicates differences in the height uncertainty of the establishment in micrometer range, which is negligible for most engineering applications.

  • 243.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. WSP Civils, Department of Geographic Information and Asset Management.
    Jensen, Anna B. O.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Horemuž, Milan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Andersson, Johan Vium
    WSP Civils, Department of Geographic Information and Asset Management.
    Investigation of the RUFRIS Method with GNSS and Total Station for Leveling2017Conference paper (Refereed)
    Abstract [en]

    The establishment of leveling benchmarks for performing geodetic measurements, for instance in construction works, is usually costly and laborious due to a mass of field works in transferring the height from nearby known benchmarks. In this study, a real-time updated free station (RUFRIS) method is investigated to be used as an alternative approach for the traditional leveling. The coordinates of a RUFRIS station are determined by establishing a total station on the point, and performing a free-station by observing some points with both Real-Time Kinematic (RTK) GNSS and total station distance and direction observations. The study is conducted based on data from the East Link project in Sweden, where a 150 km long high-speed railway is to be constructed. The results show a standard deviation of 7 mm between the RUFRIS and leveling heights in this project and imply the feasibility of replacing the traditional leveling methods with RUFRIS in projects with low accessibility to benchmarks.

  • 244.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. WSP Civils, Department of Geographic Information and Asset Management.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Jensen, Anna B. O.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Optimisation of GNSS Networks - Considering Baseline Correlations2017In: Survey review - Directorate of Overseas Surveys, ISSN 0039-6265, E-ISSN 1752-2706, p. 1-8Article in journal (Refereed)
    Abstract [en]

    By considering GNSS observations one can perform optimisation according to some pre-defined criteria and come up with the best location of receivers and optimum number of baselines. In practice, it is quite common to neglect the effect of correlations between baselines, and instead assume single-baseline adjusted data in the optimisation procedure. However, in each session of observation usually more than two receivers are simultaneously taking data from a number of common GNSS satellites, implying that the single or double difference observations are correlated. Our study designs an optimal observation plan for a GPS network in Skåne in southern Sweden, with the aim of determining possible displacements. Assuming three receivers in each session of observations leads to correlation between the GPS baselines, and consequently a fully populated weight matrix for each session of observation. A bi-objective optimisation model of precision and reliability is chosen to optimise the variance factor of each session, and eventually, design an observation plan. It is shown in this study that observing 6 out of 10 possible sessions are sufficient to enable the network to detect a 5 mm displacement at each station. Assuming that the double difference phase observations are uncorrelated changes the observation plan by retaining 2 more sessions. However, defining the weight matrix based on the double difference observations requires the correlations to be taken into account, and neglecting them leads to incorrect results.

  • 245.
    Alizadeh Khameneh, Mohammad Amin
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning. WSP Civils, Department of Geographic Information and Asset Management.
    Sjöberg, Lars E.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Jensen, Anna B. O.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Satellite Positioning.
    Optimization of GNSS Deformation Monitoring Networks by Considering Baseline Correlations2016In: FIG Working Week 2016 Proceedings, 2016Conference paper (Other academic)
    Abstract [en]

    In the study of deformations of man-made constructions or in geodynamics one usually needs to carefully monitor fixed objects attached to the deformable body. The purpose is to use precise observations to build up an accurate, reliable and possibly low-cost network around the objects to study their motion in short- or long-time intervals and to estimate the possible displacements or deformations among those objects. Frequently, such studies are performed to prevent unwanted disasters (e.g. due to earthquakes and landslides as well as the progressive or abrupt destruction of large-scale structures). This study is concerned with designing an optimal GNSS network to monitor possible deformations of a geodetic network.

    By considering GNSS observations one can perform the optimization according to some pre-defined criteria and come up with the best location of receivers and optimum number of baselines. In practice, it is quite common to neglect the effect of correlations between baselines, and instead use single-baseline adjusted data in the optimisation procedure. However, in each session of observation usually more than two receivers are simultaneously taking data from a number of common GNSS satellites. This procedure inevitably leads to between-baseline correlations. Our study designs an optimal observation plan for a GNSS monitoring network with the aim of determining possible displacements and deformations. The developed methodology will be tested on a simulated network with five points, where three receivers simultaneously take data from four satellites.

  • 246.
    Allawirdi, Teresa
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Gunduz, Helen Rebecka
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Tidsplanering och visualisering inom anläggningsprojekt2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 247.
    Allertz, Erik
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Hjelmar, Tobias
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Kvalitetssäkring av material och tjänster inom byggentreprenadbranschen2011Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Quality is the key to a well executed product or service. The construction industry hasn’t highlighted the quality in recent times which have contributed to the construction industry receiving much criticism in the field. The public sees it as an offhanded industry where errors and delays are common.The reason for this is considered to be primarily the lack of time, constant pressure to reduce costs and skills and the ability to communicate between the parties about what the correct quality really means. The industry has begun to realize that it must start setting clearer standards and that there are great opportunities for improvement.This report will give Peab an opportunity to develop their quality work. The report highlights Peab residential area of Stockholm market position with the current quality of subcontractors and suppliers. It also provides suggestions on how Peab in a better way can work with quality and with this becoming a more competitive player in the market. The conclusions that can be drawn from this study is that Peab is aware of the problem and has begun work on improvements to enhance quality of work. Peab, for example, developed tools for gathering experience. Unfortunately these methods were used poorly and not to the degree that is required. Peab also works with partnering, based on long term business relationships. Correct use of partnering increases the chances of higher quality in the projects. Concrete proposals for improvements that this report highlights include higher standards in the procurement process, dare make demands on the quality of subcontractors and suppliers, learn from the mistakes made and disseminate the knowledge within the Group and work with long-term business relationships in which partners can develop one another .

  • 248.
    Allmér, Gustaf
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Organization and management.
    Joakim, Svantesson
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Organization and management.
    How internal factors influence the work towards increased energy performance: A case study in a Swedish construction company2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    För  att  minska Europas klimatpåverkan ställer Sveriges regering och Europeiska Unionen allt högre krav på byggindustrin gällande energiprestandan i nybyggda flerbostadshus, då bostadssektorn idag står för en betydande del av Sveriges totala energiförbrukning. Byggföretagen jobbar numera för förbättrad energiprestanda i nybyggda bostäder, men skillnaden från projekt till projekt kan vara mycket stor. Man har i tidigare forskning studerat de externa faktorer som påverkar hur långt man är villig att gå energimässigt i bostadsprojekt, men lite forskning har bedrivits kring de interna faktorerna.

    Detta examensarbete har därför till syfte att identifiera dessa interna faktorer och även förklara varför de påverkar processen. För att studera detta har en fallstudie utförts på ett svenskt byggföretag där aktörer inom stora delar av den interna byggprocessen finns representerade. Semi strukturerade intervjuer genomfördes för att ge en så utförlig bild som  möjligt av processen och de faktorer som påverkar den. Intervjudatan sorterades, reducerades och analyserades genom stöd av ett teoretiskt ramverk. I detta ingår teorier från tidigare studier och olika Knowledge Managementteorier, vilka används för att tolka och förstå de faktorer som iakttagits. 

    Studiens resultat innefattar en redogörelse för viktiga observerade interna faktorer som påverkar processen i fallstudieföretaget mot mer energieffektiva flerbostadshus. Exempel på dessa är: individers kunskap och åsikt om ökad energiprestanda, tidpunkten i projektet då energifrågan lyfts upp, hur kunskap återvinns inom företaget, hur man följer upp energiberäkningar och val av medium för att dela kunskap. Många av de faktorer som identifierats är kopplade till vilken attityd och strategi  ledningen  väljer för energifrågan.  Den attityd som uppifrån förmedlas kommer också att antas av aktörerna i processen, och man har här möjligheten  att göra ett val i hur mycket man som företag vill satsa på fortsatt förbättrad energiprestanda.

  • 249. Allström, A.
    et al.
    Kristoffersson, Ida
    KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS. cVTI Swedish National Road and Transport Research Institute, Sweden.
    Susilo, Yusak
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics.
    Smartphone based travel diary collection: Experiences from a field trial in Stockholm2017In: Emerging technologies and models for transport and mobility 44th European Transport Conference Selected Proceedings, Casa Convalescència, Barcelona, Spain, 5-7 October 2016, Elsevier, 2017, Vol. 26, p. 32-38Conference paper (Refereed)
    Abstract [en]

    Currently, there is a great need for new methods to collect travel data. Traditional methods have considerable drawbacks and, at the same time, the models used to analyse the transport system require more and more detailed and high-quality data. An alternative method that stands out as very promising is to capture raw data from devices that can use any positioning technology (e.g., GPS, WiFi positioning, GSM, etc.), followed by transforming the raw data into meaningful travel data. Since most smartphones are equipped with various sensors that can be used to determine the location of the smartphone, and since smartphones are integrated in the daily life of most people, they provide an unprecedented opportunity for large-scale travel data collection. This method has a great potential to solve the problems related to the estimation of distance/travel time, geographic coding of departure/destination locations and forgotten trips and it will also provide a more detailed and extensive data set. In a recently completed research project the feasibility of replacing or complementing the traditional travel diary, with a suite of tools that make use of smartphone collected travel data has been evaluated. The advantages and disadvantages of the traditional method and the proposed method were studied. For a fair comparison, both methods have been tested in the same city, at the same time, and with the same respondents. To achieve the objectives of the project, MEILI, a system that consists of a smartphone application for capturing the movement of users and a web application for allowing the users to annotate their movement, has been deployed. The recruitment of respondents is a critical phase for traditional travel diaries and, as expected, this was the case also for the smartphone based method. A lesson learnt was that it is important to simplify the registration process as much as possible. In total 2142 trips were collected and annotated by 171 users. 51 of the users annotated trips covering more than a week. The experiences from the field trial shows that a smartphone based travel diary collection is a very useful complement to traditional travel diary collection methods since it appeals to a different age group and collects more detailed travel data for a longer period. The main findings of the paper are that smartphone based data collection is feasible, that the algorithms to save battery work well and that trips of the same respondent vary considerably depending on day of the week.

  • 250. Allström, Andreas
    et al.
    Rahmani, Mahmood
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Koutsopoulos, Haris
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Gundlegård, David
    Archer, Jeffery
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Mobile Millennium Stockholm2011In: Proceedings of the 2nd International Conference on Models and Technologies for ITS, 2011Conference paper (Refereed)
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