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  • 2651.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Chaharsooghi, K.
    Developing life-cycle phases for the DoDAF using ISO15704 Annex A (GERAM)2011In: Computers in industry (Print), ISSN 0166-3615, E-ISSN 1872-6194, Vol. 62, no 3, p. 253-259Article in journal (Refereed)
    Abstract [en]

    This paper presents a development of the US Department of Defense Architecture Framework (DoDAF) based on life-cycle concept of the Generalized Enterprise Reference Architecture and Methodology (GERAM) framework/ISO 15704:2000 requirements. Previous research has identified areas of concern within DoDAF by analyzing and evaluating DoDAF against GERAM and potentially assisting in its future development. This paper aims to extend existing architecture description process and artifacts within DoDAF that match the scope of the GERAM life-cycle phases. For this development we use life-cycle aspect of three well-known reference architectures (including PERA, CIMOSA, and GRAI-GIM) that were the basis in formation of GERAM.

  • 2652.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Modeling the Effects of ICT on Environmental Sustainability: Revisiting a System Dynamics Model Developed for the European Commission2015In: ICT Innovations for Sustainability / [ed] Hilty, L.M.; Aebischer, B., Switzerland: Springer Publishing Company, 2015, p. 449-474Chapter in book (Refereed)
    Abstract [en]

    This chapter revisits a System Dynamics model developed in 2002 with the aim of exploring the future impacts of Information and Communication Technology (ICT) on environmental sustainability in the EU, which then consisted of 15 countries. The time horizon of the study was 20 years (2000–2020). We analyze the results in light of empirical data that is now available for 2000–2012. None of the three scenarios that were developed by experts to specify the external factors needed to run the model were realistic from today’s point of view. If the model is re-run with more realistic input data for the first half of the simulation period, however, the main results regarding the impact of ICT remain qualitatively the same; they seem to be relatively robust implications of the causal system structure, as it is represented in the model. Overall, the impacts of ICT for mitigating greenhouse gas emissions and other environmental burdens for 2020 tend to be slightly stronger if the simulation is based on the empirical data now available.

  • 2653.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Hilty, Lorenz M.
    School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. Empa, Swiss Federal Laboratories for Materials Science and Technology. Department of Informatics, University of Zurich.
    Modelling Rebound Effects in System Dynamics2014In: Proceedings of the 28th Conference on Environmental Informatics - EnviroInfo 2014 - ICT for Energy Efficiency / [ed] Marx Gómez, J., Sonnenschein, M., Vogel, U., Winter, A., Rapp, B., Giesen, N., Germany: BIS Oldenburg, 2014Conference paper (Refereed)
    Abstract [en]

    The induction of demand by increasing the efficiency of a production or consumption process is known as the rebound effect. Feedback loops in System Dynamics can be used to conceptualize the structure of this complex phenomenon and also for communicating model-based insights. In passenger transport, the rebound effect can be induced through increased cost efficiency (direct economic rebound) and/or increase in speed (time rebound). In this paper we review and compare two models on environmental effects of passenger transport—including a model on the role of information and communication technology. We highlight the feedback mechanisms used to deal with the rebound effect (price, efficiency, and time rebound).

  • 2654.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. Department of Informatics, University of Zurich, Zurich, Switzerland.
    Hilty, Lorenz M
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. Department of Informatics, University of Zurich, Zurich, Switzerland.
    Simulating the future impact of ICT on environmental sustainability: validating and recalibrating a system dynamics model - Background Data2014Report (Other academic)
    Abstract [en]

    This report serves as supplementary material to the book chapter “Modeling the Effects of ICT on Environmental Sustainability: Revisiting a System Dynamics Model Developed for the European Commission” (Achachlouei and Hilty 2015) published in the book “ICT Innovations for Sustainability” (Hilty and Aebischer 2015). The current report was referred to in the book chapter whenever the data to be presented exceeded the space provided for the book chapter.

  • 2655.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. Swiss Federal Laboratories for Materials Science and Technology (Empa) and University of Zurich, Department of Informatics.
    System Dynamics vs. agent-based modeling—comparing models and approaches: A literature review and a transformation procedureManuscript (preprint) (Other academic)
    Abstract [en]

    Systems modeling and simulation methods such as System Dynamics (SD) and agent-based (AB) modeling have been used to foster a better understanding of the dynamics and complexity of natural, technical, and social systems. System Dynamics provides an aggregate-level perspective, highlighting thinking in feedback loops and employing differential equations to model the causal relations in a system, exploring the system's dynamics by numerically solving the equations. Agent-based modeling, in a bottom-up method, focuses on constituent units (agents) and their interactions to explore the emerging behavior at a system level by means of simulation. Comparing these modeling methods can help us understand their strengths and weaknesses in order to choose the right approach for a given modeling problem. It may also support the analysis of a given system to build multiple models using the different approaches and comparing them, in particular to treat fundamental uncertainties in systems modeling and simulation. In this paper, we review the existing studies comparing the SD and AB approaches and models, investigating the aims, methodology, and results of such comparative studies. We also highlight lessons learned for future model comparisons by examining how the corresponding SD and AB models are built for the purpose of comparison. A procedure for transforming System Dynamics models into agent-based models is presented and discussed using examples from the literature.

  • 2656.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). Empa – Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Lab , 9014 St. Gallen, Switzerland .
    Hilty, Lorenz M.
    KTH, School of Computer Science and Communication (CSC), Centres, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. University of Zürich, , Department of Informatics, CH-8050 Zürich, Switzerland; Empa – Swiss Federal Laboratories for Materials Science and Technology, Technology and Society Lab , 9014 St. Gallen, Switzerland .
    Using Systems Thinking and System Dynamics Modeling to Understand Rebound Effects2016In: Advances And New Trends In Environmental And Energy Informatics / [ed] Jorge Marx Gómez, Michael Sonnenschein, Andreas Winter, Ute Vogel, Barbara Rapp Nils Giesen, Cham, Switzerland: Springer Publishing Company, 2016, p. 237-255Chapter in book (Refereed)
    Abstract [en]

    Processes leading to an increase of demand for a resource as a consequence of increasing the efficiency of using this resource in production or consumption are known as (direct) rebound effects. Rebound effects at micro and macro levels tend to offset the reduction in resource consumption enabled by progress in efficiency. Systems thinking and modeling instruments such as causal loop diagrams and System Dynamics can be used to conceptualize the structure of this complex phenomenon and also to communicate model-based insights. In passenger transport, the rebound effect can be invoked by increased cost efficiency (direct economic rebound) and/or increase in speed (time rebound). In this paper we review and compare two existing models on passenger transport—including a model on the role of information and communication technology—with regard to the feedback loops used to conceptualize rebound effects.

  • 2657.
    Ahmadi Achachlouei, Mohammad
    et al.
    Enterprise Architecture Center.
    Jalalinia, S
    A Conceptual Framework (4P) for Independent Verification and Validation of Enterprise Architecture Projects2009Conference paper (Other (popular science, discussion, etc.))
  • 2658. Ahmadi Achachlouei, Mohammad
    et al.
    Karimi, Rasoul
    Nekui, Farnaz
    Bahram Behroozi, Amir
    Mafakheri, Kianoosh
    Two New Architectures to Improve the Software Development Process2007In: International Journal Communications of SIWN, ISSN 1757-4439, Vol. 1, no 4, p. 369-372Article in journal (Refereed)
  • 2659.
    Ahmadi Achachlouei, Mohammad
    et al.
    School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Moberg, Åsa
    School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC. KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies.
    Carbon and ecological footprints of a magazine: Print vs. tablet editions2012Conference paper (Other academic)
    Abstract [en]

    Information and communication technology (ICT), in competition with traditional applications, is providingnew ways to access media content. Similar to print media, ICT-based media has environmental benefits andburdens alike. The overall goal of the present study is to assess the potential environmental impacts”’from a lifecycle perspective”’of a print magazine with its electronic version read on tablets. Important goals are to identifywhich activities give rise to the main impacts, in both print and tablet editions, and to identify the key factorsinfluencing the overall environmental impacts, in both editions. Moreover, data gaps and uncertainties areaddressed.The methodology used in the study is life cycle assessment (LCA). The environmental impacts assessedinclude climate change, cumulative energy/exergy demand, metal depletion, photochemical oxidant formation,particulate matter formation, terrestrial acidification, freshwater/marine eutrophication and fossil depletion.The results indicate that it is hard to compare print and tablet editions of a magazine due to difficulties indefining the function, and that different functional units indicate different preferences in terms of environmentalimpacts. Also, differences between emerging (low number of readers and low reading time per copy) andmature (high number of readers and higher reading time per copy) tablet versions leads to various results in thecomparison between print and tablet versions.The studied tablet version in its emerging stage gives rise to higher potential environmental impacts per readerthan the print version; however with an assumed mature tablet version the impacts are generally lower perreader. This illustrates clearly the importance of the number of readers to spread the environmental impactsover.

  • 2660.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies (moved 20130630). School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Moberg, Åsa
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies (moved 20130630). School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Life cycle assessment of a magazine: part 2: A comparison of print and tablet editions2015In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 19, no 4Article in journal (Refereed)
    Abstract [en]

    The rapid development of information and communications technology (ICT) is providing new ways to access media content. Electronic media are sometimes more advantageous from an environmental perspective than paper-based media solutions, but ICT-based media can also bring environmental burdens. This study compared the potential environmental impacts in a life cycle perspective of a print edition of a magazine and that of its electronic edition read on a tablet device. Important objectives were to identify activities giving rise to the main environmental impacts for both the print and tablet editions, determine the key factors influencing these impacts, and address data gaps and uncertainties. A detailed assessment of the tablet edition is provided in a previous article (part 1), whereas this article compares it with the print edition. The methodology used was life cycle assessment and the environmental impacts assessed included climate change, cumulative energy/exergy demand, metal depletion, photochemical oxidant formation, particulate matter formation, terrestrial acidification, freshwater eutrophication, marine eutrophication, and fossil depletion. Use of different functional units to compare the print and tablet editions of the magazine resulted in different relative environmental impacts. In addition, emerging (low number of readers and low reading time per copy) and mature (higher number of readers and higher reading time per copy) tablet editions yielded varying results. The emerging tablet edition resulted in higher potential environmental impacts per reader than the print edition, but the mature tablet edition yielded lower impacts per reader in half the impact categories assessed. This illustrates the importance of spreading the environmental impacts over a large number of readers. The electricity mix used in product system processes did not greatly affect the results of tablet/print comparisons, but overall number of readers for the tablet edition, number of readers per copy for the print edition, file size, and degree of use of the tablet device proved crucial for the comparison results.

  • 2661.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies. School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Moberg, Åsa
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies. School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Hochschorner, Elisabeth
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Environmental Strategies. School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Climate Change Impact of Electronic Media Solutions: Case Study of the Tablet Edition of a Magazine2013In: ICT4S 2013: Proceedings of the First International Conference on Information and Communication Technologies for Sustainability, ETH Zurich, February 14-16, 2013, ETH, Zurich, 2013Conference paper (Refereed)
    Abstract [en]

    Shifts from print media to electronic media may be regarded as apossibility for promoting sustainability. However, the benefits ofelectronic media are not unquestioned. Previous studies on theenvironmental impacts of print and electronic media have shownthat there is no easy answer. Contributing to this field of research,the present study sought to assess the climate change impact ofthe tablet edition of a magazine using a life cycle perspective.Results showed that with few readers the emerging tablet versionhad a higher potential climate change impact per reader than themature tablet version, although the latter had a substantiallylonger reading time per copy. The contribution of contentproduction, electronic distribution, reading on tablet and wastetreatment of tablet to the impact was analysed. The sensitivityanalysis of electricity mix indicated that this was an importantfactor that clearly influenced the overall results.

  • 2662.
    Ahmadi Achachlouei, Mohammad
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Moberg, Åsa
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering. School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    Hochschorner, Elisabeth
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms).
    Life Cycle Assessment of a Magazine: Part I: Tablet Edition in Emerging and Mature States2015In: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 19, no 4Article in journal (Refereed)
    Abstract [en]

    Information and communication technology (ICT) is providing new ways to access media content. ICT has environmental benefits and burdens. The overall goal of the present study was to assess the environmental impacts of production and consumption of magazines read on tablets from a life cycle perspective. Important goals were to identify the activities giving rise to the main impacts and the key factors influencing the overall environmental impacts. Data gaps and uncertainties were also addressed. The results are compared against those for the print edition of the magazine in a separate article (part 2). The methodology used in the study was life cycle assessment. The environmental impacts assessed included climate change, cumulative energy/exergy demand, metal depletion, photochemical oxidant formation, particulate matter formation, terrestrial acidification, freshwater/marine eutrophication, fossil depletion, human toxicity, and ecotoxicity. The results indicate that content production can be the major contributor to environmental impacts if readers are few (as for the emerging version of the magazine studied). Assuming more readers (more mature version) or a larger file size for the tablet magazine, electronic storage and distribution may be the major contributor. Thus, in contrast to previous studies on electronic media, which reported a dominant impact of the use phase, this study found a higher impact for content production (emerging version) and electronic storage and distribution (mature version). However, with inefficient, low overall use of the tablet with a mature version of the tablet magazine, the greatest impact was shown to come from the reading activity (i.e., the use phase). In conclusion, the relative impacts of the tablet magazine would decrease considerably with high numbers of readers, their efficient use of the tablet (i.e., for many purposes over a long life of the device), and a smaller magazine file.

  • 2663.
    Ahmadi, Ajda
    KTH, School of Technology and Health (STH).
    Design of an Improved Rapid Infuser for Safe and Reliable Fluid Resuscitation during Surgical Care2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Rapid infusers are used for rapid fluid administration as a part of medical treatment during surgical procedures. The rapid infusers on the market today have proved to present various functional, usability and safety issues for the customers and the problems have not been adequately addressed. This has motivated SLL Innovation to develop a new improved rapid infusion system. The primary reason for considering the development of a rapid infuser device was to meet customer demands and improve safety during the acute situations when the system is to be used. The Quality Function Deployment method was used to describe the design problem systematically and facilitate the development of an improved design. To investigate the users’ issues with existing rapid infusion devices, qualitative semi-structured interviews were conducted individually with hospital staff that had experience with the rapid infuser. Customer requirements were subsequently identified to form a basis for the development process.

    The results of the study indicated an evident demand for a new product. A three-dimensional (3D) computer aided design (CAD) solution was presented with enhanced properties and features that met the specifications identified. All the customer requirements were addressed in the final result. Safety was the highest rated engineering specification, thus a lot of time and effort was dedicated to solutions that could affect the safety of the system positively.

    Although the final design is expected to be more efficient and safer than the competition, further research and work is needed before this can be ensured.

  • 2664.
    Ahmadi, Ajda
    et al.
    KTH, School of Technology and Health (STH).
    Dizon, Lucas
    KTH, School of Technology and Health (STH).
    Kärlstelhetsdetektion genom mätning av tryck och deformation: En experimentell ultraljudsbaserad studie2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 2665.
    Ahmadi, Leila
    et al.
    Energy, Mining and Environment, National Research Council Canada.
    Young, Steven B.
    School of Environment, Enterprise and Development|, University of Waterloo.
    Fowler, Michael
    Department of Chemical Engineering, University of Waterloo.
    Fraser, Roydon A.
    Department of Mechanical and Mechatronics Engineering, University of Waterloo.
    Ahmadi Achachlouei, Mohammad
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Environmental Strategies Research (fms). School of Computer Science and Communication (CSC), Centres, KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Sustainable Communications, CESC.
    A cascaded life cycle: reuse of electric vehicle lithium-ion battery packs in energy storage systems2015In: The International Journal of Life Cycle Assessment, ISSN 0948-3349, E-ISSN 1614-7502Article in journal (Refereed)
    Abstract [en]

    Purpose

    Lithium-ion (Li-ion) battery packs recovered from end-of-life electric vehicles (EV) present potential technological, economic and environmental opportunities for improving energy systems and material efficiency. Battery packs can be reused in stationary applications as part of a “smart grid”, for example to provide energy storage systems (ESS) for load leveling, residential or commercial power. Previous work on EV battery reuse has demonstrated technical viability and shown energy efficiency benefits in energy storage systems modeled under commercial scenarios. The current analysis performs a life cycle assessment (LCA) study on a Li-ion battery pack used in an EV and then reused in a stationary ESS.

    Methods

    A complex functional unit is used to combine energy delivered by the battery pack from the mobility function and the stationary ESS. Various scenarios of cascaded “EV mobility plus reuse in stationary clean electric power scenarios” are contrasted with “conventional system mobility with internal combustion engine vehicles plus natural gas peaking power.” Eight years are assumed for first use; with 10 years for reuse in the stationary application. Operational scenarios and environmental data are based on real time-of-day and time-of-year power use. Additional data from LCA databases are utilized. Ontario, Canada, is used as the geographic baseline; analysis includes sensitivity to the electricity mix and battery degradation. Seven environmental categories are assessed using ReCiPe.

    Results and discussion

    Results indicate that the manufacturing phase of the Li-ion battery will still dominate environmental impacts across the extended life cycle of the pack (first use in vehicle plus reuse in stationary application). For most impact categories, the cascaded use system appears significantly beneficial compared to the conventional system. By consuming clean energy sources for both use and reuse, global and local environmental stress reductions can be supported. Greenhouse gas advantages of vehicle electrification can be doubled by extending the life of the EV batteries, and enabling better use of off-peak low-cost clean electricity or intermittent renewable capacity. However, questions remain concerning implications of long-duration use of raw material resources employed before potential recycling.

    Conclusions

    Li-ion battery packs present opportunities for powering both mobility and stationary applications in the necessary transition to cleaner energy. Battery state-of-health is a considerable determinant in the life cycle performance of a Li-ion battery pack. The use of a complex functional unit was demonstrated in studying a component system with multiple uses in a cascaded application.

  • 2666.
    Ahmadi, Mazaher
    et al.
    Bu Ali Sina Univ, Fac Chem, Hamadan, Iran..
    Moein, Mohammad Mahdi
    Karolinska Inst, Ctr Psychiat Res, Dept Clin Neurosci, SE-17176 Stockholm, Sweden.;Stockholm Cty Council, SE-17176 Stockholm, Sweden..
    Madrakian, Tayyebeh
    Bu Ali Sina Univ, Fac Chem, Hamadan, Iran..
    Afkhami, Abbas
    Bu Ali Sina Univ, Fac Chem, Hamadan, Iran..
    Bahar, Soleiman
    Univ Kurdistan, Fac Sci, Dept Chem, Sanandaj, Iran..
    Abdel-Rehim, Mohamed
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics. Karolinska Inst, Ctr Psychiat Res, Dept Clin Neurosci, SE-17176 Stockholm, Sweden.;Stockholm Cty Council, SE-17176 Stockholm, Sweden..
    Reduced graphene oxide as an efficient sorbent in microextraction by packed sorbent: Determination of local anesthetics in human plasma and saliva samples utilizing liquid chromatography-tandem mass spectrometry2018In: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 1095, p. 177-182Article in journal (Refereed)
    Abstract [en]

    Herein, reduced graphene oxide (RGO) has been utilized as an efficient sorbent in microextraction by packed sorbent (MEPS). The combination of MEPS and liquid chromatography-tandem mass spectrometry has been used to develop a method for the extraction and determination of three local anesthetics (i.e. lidocaine, prilocaine, and ropivacaine) in human plasma and saliva samples. The results showed that the utilization of RGO in MEPS could minimize the matrix effect so that no interfering peaks at the retention times of the analytes or internal standard was observed. The high extraction efficiency of this method was approved by mean recoveries of 97.26-106.83% and 95.21-105.83% for the studied analytes in plasma and saliva samples, respectively. Intra- and inter-day accuracies and precisions for all analytes were in good accordance with the international regulations. The accuracy values (as percentage deviation from the nominal value) of the quality control samples were between - 2.1 to 13.9 for lidocaine, - 4.2 to 11.0 for prilocaine and between - 4.5 to - 2.4 for ropivacaine in plasma samples while the values were ranged from - 4.6 to 1.6 for lidocaine, from - 4.2 to 15.5 for prilocaine and from - 3.3 to - 2.3 for ropivacaine in human saliva samples. Lower and upper limit of quantification (LLOQ, ULOQ) were set at 5 and 2000 nmol L-1 for all of the studied drugs. The correlation coefficients values were >= 0.995. The limit of detection values were obtained 4 nmol L-1 for lidocaine and prilocaine, and 2 nmol L-1 for ropivacaine.

  • 2667.
    Ahmadi Moghaddam, Elham
    KTH, School of Industrial Engineering and Management (ITM), Industrial Ecology.
    Comparison of Biogas and Bioethanol for Sweden Transportation Fleet2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Biofuels were recently seen as a solution for the predicaments of our age; the “energy crisis” and the” climate change”. Today biofuels derived from food crops are a subject of debate for food hunger of the world’s poor and one of the main reasons of increased food prices. Latest studies also show that biofuels have no significant reduction in energy consumption and emissions. Today many attentions have been focused on biofuels extracted from biomass of different residual material such as agriculture residuals. Sweden produces biogas from different sources and also is one of the main users of Brazil’s bioethanol.

    In this report we aim to study two biofuel alternatives for Sweden transportation fleet; biogas from sugar beet residues in Sweden and imported bioethanol from sugarcanes from Brazil. The study is based on a life-cycle assessment (LCA) of the two mentioned biofuels. Three main units of agriculture, industrial production process and transportation is studied in the life cycle of the mentioned fuels.

    Based on energy inputs and emissions biogas from sugar beets in Sweden is a better alternative for Sweden transportation fleet. Bioethanol from Brazil is a crop-based fuel and highly energy consuming in the agricultural operations and industrial production process. Biogas fuel production requires increase in production capacity and technological developments.

  • 2668.
    Ahmadi, Mozhgan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Brage, Claes O.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Sjöström, Krister
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Engvall, Klas
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Knoef, H.
    Van De Beld, B.
    Development of an on-line tar measurement method based on photo ionization technique2011In: Catalysis Today, ISSN 0920-5861, E-ISSN 1873-4308, Vol. 176, no 1, p. 250-252Article in journal (Refereed)
    Abstract [en]

    This paper presents work in progress for development of an on-line method based on PID (Photo Ionization Detector) for quantitative measurement of tar from biomass gasification. To calibrate the method the PID signals are compared to quantitative data of individual tar compounds obtained by an established reference method. The measured response factors for the model tar compounds demonstrated very good linearity. The PID approach was tested on-line with real producer gases from an atmospheric fluidized bed gasifier operated at 800-900 °C. The results suggest that PID can be used for continuous on-line tar measurement of product gases from biomass gasification.

  • 2669.
    Ahmadi, Mozhgan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Knoef, Harrie
    Van De Beld, Bert
    Liliedahl, Truls
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Engvall, Klaus
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Development of a PID based on-line tar measurement method: Proof of concept2013In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 113, p. 113-121Article in journal (Refereed)
    Abstract [en]

    In this study, a proof of concept was conducted for an on-line tar analyzer based on photo ionization detection (PID). Tar model compounds (naphthalene, acenaphthene, acenaphthylene, fluorene, indane and indene) were used for the initial investigation of the analysis method. It was found that the analysis method has a high sensitivity and a linear behavior was observed between the PID response and the tar concentration over a wide concentration span. The on-line tar analysis method was successfully validated against the solid phase adsorption (SPA) method using a real producer gas.

  • 2670.
    Ahmadi, Mozhgan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Sjöström, Krister
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Brage, Claes
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Engvall, Klas
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Liliedahl, Truls
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Develompent of an online tar measuring method using ionization potential2010Conference paper (Refereed)
  • 2671.
    Ahmadi, Mozhgan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Sjöström, Krister
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Brage, Claes
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Liliedahl, Truls
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Knoef, Harri A.M.
    Van de Beld, Bert
    Development of an online tar measuring method for quantitative analysis of biomass producer gas2009Conference paper (Refereed)
  • 2672.
    Ahmadi, Mozhgan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Svensson, Erik Elm
    Engvall, Klas
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Application of solid phase microextraction (SPME) as a tar sampling method during real gasificationManuscript (preprint) (Other academic)
  • 2673.
    Ahmadi, Mozhgan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Svensson, Erik Elm
    Engvall, Klas
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Application of Solid-Phase Microextraction (SPME) as a Tar Sampling Method2013In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 27, no 7, p. 3853-3860Article in journal (Refereed)
    Abstract [en]

    This paper presents the result of an investigation of the potential use of solid-phase microextraction (SPME) as a tar sampling method. The SPME stationary phase used was 50 mu m of polydimethylsiloxane (PDMS) coated on a fused silica fiber. Tar model compounds normally present in a producer gas from gasifiers, benzene, toluene, indane, indene, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene, were used in the investigation. The adsorbed compounds were analyzed by injection into gas chromatography coupled to a flame ionization detector (GC- FID). The amount of adsorbed tar on the SPME fiber determined the detection and quantification limits for the method. The results showed that adsorption of tar model compounds on the SPME fiber increased with decreasing polarity. The adsorption of compounds increased with a decreasing temperature, enabling a possibility to tune the sensitivity of the method by changing the sampling temperature. Conclusively, SPME has a very high potential as a tar sampling method and, in combination with GC- FID trace analysis of tar, is a feasible application.

  • 2674.
    Ahmadi, Parisa
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Analysis of traffic patterns for large scale outdoor events: A case study of Vasaloppet ski event2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Vasaloppet is a cross country ski event which has been held in Sweden for about 50 years. Now

    more than 50,000 people of different ages participate in various cross country ski races during the

    Vasaloppet winter week in Dalarna County. This increasing demand needs good traffic and

    transportation planning to avoid congestion and provide safe, on time and environmentally

    friendly transportation for participants and visitors to the area. The key for a good event traffic

    planning is reliable and up-to-date traffic data which is not available for the Vasaloppet winter

    week.

    This study is an attempt to collect traffic data in order to find the movement patterns in the area

    and estimate origin-destination matrices for the main event of Vasaloppet week. Based on

    resources and time limitation it was decided to use a web-base

    d participants’ survey in order to

    collect traffic data. The link to the survey was sent to email address of a sample of 5000

    participants.

    About 64% of the participants drove from their home town to the area and about 31 percent

    travelled by bus. Train and airplane have a very small share in travel mode to the area. Malungsälen,

    Mora and Älvdalen are three municipalities in Dalarna County with the highest share in

    accommodating participants. On the day of the race, bus and car have approximately the same

    share in travel mode with 45% and 47% respectively.

  • 2675.
    Ahmadi, Sareh
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Structure-dependent charge transfer at the interafce between organic thin films, and metals and metal oxides2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The purpose of the research work, presented in this thesis is to offer a detailed atomic level study of interfaces created by adsorption of organic molecules on metals and metal oxides to point out significant impact of substrate, dye structure as well as different mediators on the charge transfer at these interfaces, which is proven to influence the device performance to a great extent.

    Adsorption of organic photosensitive molecules on metals and metal-oxides is the main focus of this thesis. Phthalocyanines which are organic semiconductors offer a broad range of properties, such as thermal and chemical stability, high charge mobility and strong absorption coefficient in the visible and near-IR regions, which make them very attractive to be applied in various systems and devices. Fuel cells, organic field-effect transistors (OFETs), organic light emitting diodes (OLEDs) and solar cells are examples of phthalocyanine’s applications. The main focus of this work is to characterize the interfaces of Dye Sensitized Solar Cells (DSSCs).

    DSSC was invented by Michael Grätzel and Brian O’Regan in 1988. At the heart of this cell there is an oxide which is coated by a photosensitive dye. Under illumination, an electron is excited from HOMO to LUMO of the molecule, which can be further transferred to the conduction band of the oxide by a proper energy level alignment. The original state of the dye is regenerated by electron donation via the electrolyte, which usually is an organic solvent containing a redox couple e.g., iodide/triiodide. The iodide is regenerated by reduction of triiodide at the counter electrode. To improve the functionality of the cell, different additives can be added to the electrolyte.

    To mimic the interfaces of this cell, molecular layers of MPc (M: Fe, Zn, Mg) are adsorbed on both metallic surfaces, Au(111) and Pt(111), and rutile TiO2(110). Layers of iodine were inserted between metallic substrates and dyes to investigate the electronic properties and charge transfer at these multi-interface systems. 4-tert-butyl pyridine is a significant additive to the electrolyte and has proven to enhance the cell’s performance. This molecule was also adsorbed on Pt(111) and TiO2(110). Phthalocyanines were deposited by organic molecular beam deposition and 4TBP was evaporated at room temperature. Surface structures and reconstructions were confirmed by LEED measurements. Surface sensitive synchrotron radiation based spectroscopy methods, XPS and NEXAFS were applied to characterize these surfaces and interfaces. STM images directly give a topographical and electronic map over the surface. All measurements were carried out in UHV condition.

    When MPc was adsorbed on Au(111) and TiO2(110), charge transfer from molecule to substrate is suggested, while the opposite holds for MPc adsorbed on Pt(111). Moreover, stronger interaction between MPc and Pt(111) and TiO2(110) compared to Au(111) also demonstrates the effect of substrate on the charge transfer at the interface. The stronger interaction observed for these two substrates disturbed the smooth growth of a monolayer; it also resulted in bending of the molecular plane. Interaction of MPc with metallic surfaces was modified by inserting iodine at the interface. Another substrate-related effect was observed when MgPc was adsorbed on TiO2(110);  and -cross linked surfaces, where the surface reconstruction directly affect the molecular configuration as well as electronic structure at the interface. Besides, it is shown that the d-orbital filling of the central metal atom in MPc plays an important role for the properties of the molecular layer as well as charge transfer at the interface.

    Upon adsorption of 4TBP on Pt(111), C-H bond is dissociatively broken and molecules is adsorbed with N atoms down. Modification of surface by iodine, prevent this dissociation. In the low coverage of iodine, there is a competition between 4TBP and iodine to directly bind to Pt(111). Investigation on the adsorption of 4TBP on TiO2(110) illustrated that these molecules in low coverage regime, prefer the oxygen vacancy sites and their adsorption on these sites, results in a downward band bending at the substrate’s surface. 

  • 2676.
    Ahmadi, Sareh
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Agnarsson, Björn
    Bidermane, Ieva
    Wojek, Bastian M.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Noël, Quentin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Sun, Chenghua
    Göthelid, Mats
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Site-dependent charge transfer at the Pt(111)-ZnPc interface and the effect of iodine2014In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 140, no 17, p. 174702-Article in journal (Refereed)
    Abstract [en]

    The electronic structure of ZnPc, from sub-monolayers to thick films, on bare and iodated Pt(111) is studied by means of X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and scanning tunneling microscopy. Our results suggest that at low coverage ZnPc lies almost parallel to the Pt(111) substrate, in a non-planar configuration induced by Zn-Pt attraction, leading to an inhomogeneous charge distribution within the molecule and an inhomogeneous charge transfer to the molecule. ZnPc does not form a complete monolayer on the Pt surface, due to a surface-mediated intermolecular repulsion. At higher coverage ZnPc adopts a tilted geometry, due to a reduced molecule-substrate interaction. Our photoemission results illustrate that ZnPc is practically decoupled from Pt, already from the second layer. Pre-deposition of iodine on Pt hinders the Zn-Pt attraction, leading to a non-distorted first layer ZnPc in contact with Pt(111)-I(root 3x root 3) or Pt(111)-I(root 7x root 7), and a more homogeneous charge distribution and charge transfer at the interface. On increased ZnPc thickness iodine is dissolved in the organic film where it acts as an electron acceptor dopant.

  • 2677.
    Ahmadi, Sareh
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Agnarsson, Björn
    Bidermane, Leva
    Wojek, Bastian M.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Noël, Quentin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Sun, Chenghua
    Göthelid, Mats
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Effect of the iodineon the site-dependent charge transfer at the Pt(111)-ZnPc interfaceManuscript (preprint) (Other academic)
  • 2678.
    Ahmadi, Sareh
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Bidermane, Leva
    Noël, Quentin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Sun, Chenghua
    Göthelid, Mats
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Dissociative bonding of 4-tert-butyl pyridine to Pt(111) and surface passivation by iodineManuscript (preprint) (Other academic)
  • 2679.
    Ahmadi, Sareh
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Shariati, M. Nina
    Yu, Shun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Göthelid, Mats
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Molecular layers of ZnPc and FePc on Au(111) surface: Charge transfer and chemical interaction2012In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 137, no 8, p. 084705-Article in journal (Refereed)
    Abstract [en]

    We have studied zinc phthalocyanine (ZnPc) and iron phthalocyanine (FePc) thick films and monolayers on Au(111) using photoelectron spectroscopy and x-ray absorption spectroscopy. Both molecules are adsorbed flat on the surface at monolayer. ZnPc keeps this orientation in all investigated coverages, whereas FePc molecules stand up in the thick film. The stronger inter-molecular interaction of FePc molecules leads to change of orientation, as well as higher conductivity in FePc layer in comparison with ZnPc, which is reflected in thickness-dependent differences in core-level shifts. Work function changes indicate that both molecules donate charge to Au; through the pi-system. However, the Fe3d derived lowest unoccupied molecular orbital receives charge from the substrate when forming an interface state at the Fermi level. Thus, the central atom plays an important role in mediating the charge, but the charge transfer as a whole is a balance between the two different charge transfer channels; pi-system and the central atom.

  • 2680.
    Ahmadi, Sareh
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Yu, Shun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Soldemo, Markus
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Sun, Chenghua
    Göthelid, Mats
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Reduced Au-MPc hole injection barrier by an intermediate iodine layerManuscript (preprint) (Other academic)
  • 2681.
    Ahmadi, Sareh
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Yu, Shun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Soldemo, Markus
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Zuleta, Marcelo
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Palmgren, Pål
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Göthelid, Mats
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Material Physics, MF.
    Charge transfer and band bending on TiO2(110)-MgPcManuscript (preprint) (Other academic)
  • 2682.
    Ahmadi, Seyed Alireza
    et al.
    KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Shames, Iman
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Scotton, Francesco
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Huang, Lirong
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Sandberg, Henrik
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Johansson, Karl Henrik
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Wahlberg, Bo
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Towards more efficient building energy management systems2012In: Proceedings - 2012 7th International Conference on Knowledge, Information and Creativity Support Systems, KICSS 2012, IEEE , 2012, p. 118-125Conference paper (Refereed)
    Abstract [en]

    As a first step towards developing efficient building energy management techniques, in this paper, we first study the energy consumption patterns of heating, ventilation and cooling (HVAC) systems across the KTH Royal Institute of Technology campus and we identify some possible areas where energy consumption can be made less wasteful. Later, we describe a test-bed where wireless sensor networks are used to collect data and eventually control the HVAC system in a distributed way. We present some of the data, temperature, humidity, and CO2 measurements, that are collected by the aforementioned network and compare them with the measurements collected by the legacy sensors already in place. In the end we present a preliminary result on modelling the dynamics of the temperature, humidity, and CO2 using the data gather by the sensor network. We check the validity of the model via comparing the out put of the system with measured data. As a future work we identify the possibility of using the models obtained here for model based control, and fault detection and isolation techniques.

  • 2683.
    Ahmadi, Seyedhesam
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Bahmani, Mehrdad
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Reglering av effektflöde i HVDC-system genom centraliserad och distribuerad spänningskontroll i realtid2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    “High voltage direct current” (HVDC) teknologi har blivit allt viktigare teknik för att integrera förnybara energikällor i elnätet. För att styra ett sådant elsystem på bästa möjliga sätt krävs optimala kontrollstatergier både för omvandlarna och nätet. Så syftet med detta projekt är att undersöka hur olika regleringsmetoder, såsom centraliseradoch distribuerad spänningskontroll, kan påverka driften i ett 4-terminal HVDC-system. Ett optimalt effektflöde uppstår i systemet endast när likspänningen inte avviker från sitt börvärde och det uppnås genom att ha aktiv effekt regulator i varje nod i nätet. Olika scenarier som ändring av effektens börvärde och omvandlaravbrott har simulerats med hjälp av HIL-processen i realtid. Simuleringarna hjälper till att analysera hur väl dem implementerade regleringsmetoder i nodernas regulatorer hantera dessa förändringar. Resultatet ger bevis på att både centraliseradoch distruebued metoden har positiva och negativa aspekter. Fördelen med centraliserade metoden är att den ger en väldefinierad operationspunkt men den hanterar den inte svåra transienter (tex. avbrott) vilket distribuerade metoden gör.

  • 2684.
    Ahmadi Svensson, Mozhgan
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Engineering.
    Sampling and Analysis of Tars by Means of Photo Ionization Detection and Solid Phase Micro Extraction2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Gasification of biomass will likely play an important role in the production of energy and chemicals in a future sustainable society. However, during gasification impurities, such as tars, will be formed. Tars may cause fouling and blockages of equipment downstream the gasifier. It is therefore important to minimize the formation of tars, alternatively to remove the formed tars. These processes need to be monitored, which makes it necessary to develop tar analysis methods suitable for this task.

    This work describes the development of two tar analysis methods, an on-line method based on a photoionization detector (PID) and an off-line method based on solid phase microextraction (SPME). Both methods were successfully validated against the established solid phase adsorption (SPA) method.

    The method based on PID was shown to have a very fast response time. Furthermore, the PID method is selective towards tar, but only limited information will be obtained regarding the composition of the tar compounds. The PID method is suitable for applications where it is important to detect fast changes of the tar concentration, i.e. process monitoring.

    The SPME method was shown to be a very sensitive method for qualitative and quantitative tar analysis. The sampling temperature was shown to be crucial for obtaining analysis results with the wanted detection limit. The SPME method is suitable for applications where extremely low detection and quantification limits are needed, i.e. for syngas production.

     

  • 2685.
    Ahmadi, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Market orientation and public housing companies in the Swedish declining market2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The licentiate thesis consists of three papers with the particular topic in public housing. They discuss how the public housing companies manage the transition to higher economic demands meeting increased customer and market requirements. These studies focus specifically on how the public housing company deal with market challenges associated with the decision to demolish, maintain and/or new construction. Market-oriented perspective can be a tool for the public housing companies to achieve better customer value and enhance economic development. Although the market orientation concept has contributed to valuable improvements in research, the thesis assumes that it is necessary to distinguish between that the public housing companies operate market-oriented to meet customer requirements and their focus on innovation.

    Paper I develops market/innovation types and then investigates how public housing companies adapt to these types. It was found that economic conditions in the municipality have a major impact on the housing companies, causing them to act innovatively and create superior customer value by innovations. The study confirms that the implementation of market and innovation orientation contributes to competitive advantages in growing markets, while weak economic conditions impair implementation in declining markets.

    Paper II addresses how public housing companies in declining markets act based on the concept of market intelligence. This study suggested and tested whether there is a positive link between collecting customer information, disseminating it in the organization, and responding to customer needs, and whether this link has an impact on strategic performance. The result shows that weak links exist in the process; the efficiency of intelligence distribution in public housing companies is affected mainly by their responsiveness to customer needs.

    Paper III also addresses the public housing companies’ market strategies in declining markets. This study, based on a market-strategic perspective, compares how public housing companies act in relation to customer wants compared to the private housing market. The result shows that public housing companies are more engaged in carrying out new construction, renovation, and reconstruction, as well as taking more social responsibility compared to the private sector. In particular, their concern for the customers’ social needs is evident.

  • 2686.
    Ahmadi, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Moderating effects on market orientation and strategic performance: A study of public housing companies in Sweden2018In: Article in journal (Refereed)
  • 2687.
    Ahmadi, Zahra
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics. Högskolan i Gävle.
    The role of market orientation in public housing companies:: A study of MO’s effect on construction strategies2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The development of public housing companies in Sweden is strongly influenced by legal, economic, and demographic changes. The companies long tradition of taking responsibility for customer welfare in living have recently been criticized for excessive dominance over price setting, which is claimed to give them competitive advantages in the housing market. New legislation in 2011 requires financial return on investment, implying increased competition with radical changes for the companies. Because of the law, they find themselves transitioning from the role of being responsible for living conditions in Sweden to having to work in a businesslike manner with increased competition.The purpose of this dissertation is to analyze how the public housing companies’ deal with market orientation constructs and what their impact is on construction strategy choices. Theoretically, the market orientation concept is seen as a tool for companies to create superior value for the customers and influence strategic performance, which is a relationship tested and analyzed in this dissertation.The research was conducted through data collection stages using qualitative and quantitative methods. In the first stage, a qualitative pilot study was conducted with interviews of 15 managers in 11 public housing companies in central Sweden. In the second stage, two quantitative comparative studies of public and private housing companies in declining markets in central Sweden were conducted, collecting data from 23 (22 survey respondents) public and 37 private housing companies (16 respondents). In the third and final stage, two quantitative studies were conducted, collecting data from all 289 public housing companies (165 respondents) in Sweden.Results of the five studies show, firstly, that economic condition in the municipality have a major impact on the housing companies’ construction strategies, causing them to act innovatively in order to create superior customer value. Secondly, market orientation efforts contribute to competitive advantages in growing markets, while weak economic conditions limit the companies’ construction strategy choices in declining markets. After analyzing the link between market orientation constructs and construction strategy in declining markets, results showed that the public housing companies demonstrate higher responsiveness to customer demands compared to the private sector, but these have no effects on construction strategy. Thirdly, the analysis of moderating (external) and mediating (corporate social responsibility) effects on the market orientation and construction strategy relationship confirms that economic conditions in society influence construction strategy planning and decisions. The results of the mediating effects of CSR indicate that environmental and social issues have a positive influence on the market orientation and construction strategy relationship.

  • 2688.
    Ahmadi, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics. University of Gävle, Sweden.
    Lind, Hans
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Strategies in decling housing markets: a comparison of public and private housing companiesManuscript (preprint) (Other academic)
  • 2689.
    Ahmadi, Zahra
    et al.
    Gävle.
    Lind, Hans
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Sustainable strategies in a declining housing market: a comparative study2018In: International Journal of Management Practice, ISSN 1477-9064, E-ISSN 1741-8143, Vol. 11, no 4, p. 400-421Article in journal (Refereed)
    Abstract [en]

    The purpose of this study is first to examine and compare sustainable strategies within public and private housing companies in declining markets in central Sweden. Then, the study evaluates the impact of new legislation that requires public housing companies to act in a ‘businesslike’ way, in the same way as a long-term private company. A quantitative study was conducted based on a survey sent to 72 housing companies. The results show that public housing companies are more strategy oriented than private housing companies. The results can be viewed as an on-going interaction process, where a company’s strategies affect its profit. The study aims toincrease the understanding of activities within housing companies in adeclining market that engage the companies in sustainable strategies to improve their market knowledge and profit.

  • 2690.
    Ahmadi, Zahra
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management, Building and Real Estate Economics.
    Sundström, Agneta
    The market intelligence impact on strategic performance in declining markets2017In: International Journal of Applied Business and Economic Research, Vol. 15, no 15, p. 457-473Article in journal (Refereed)
    Abstract [en]

    This study examines how companies in declining markets operate in the context of market intelligence, responding to customer needs and applying them to strategic performance. A quantitative survey was sent to 214 public housing companies. The results indicate that market intelligence creates commitment and is significant. A positive relationship was found between data gathering, dissemination, and responsiveness, which indicates that the companies comprehend market needs but companies have difficult to manage construction strategies that improve strategic performance. There was a low value of strategic performance; a link between market intelligence and the chosen strategy was not confirmed. Companies know what the market wants but base their decision on previous strategic performance on economic conditions in the municipality instead.

  • 2691.
    Ahmadi, Zahra
    et al.
    University of Gävle, Sweden.
    Sundström, Agneta
    The Role of Market Intelligence in Declining Markets: Public Housing Companies in SwedenManuscript (preprint) (Other academic)
  • 2692.
    AHMADI ÅMAN, HEIDI
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    ANDERSSON, EFFIE
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Development of a Lightening System in the Village Lwengo Bassila2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report describes a master thesis conducted at the Machine Department at the KTH Royal Institute of Technology. The project was based on a field study done in the Democratic Republic of the Congo (DR Congo) and the aim was to provide a village in Menikongo with lighting and electricity for charging mobile phones. One important purpose was to improve the quality of life for the villagers.The field study was done as a Minor Field Study (MFS) during eight weeks and was financed by Sida and PIEp. The study was conducted in the village Lwengo Bassila in the area Menikongo about a ten hour car ride away from the capital Kinshasa.DR Congo is situated in central Africa and is the second largest country in Africa. The population is about 73.6 million, which puts DR Congo on 19th place in the world of countries with the highest number of inhabitants. The country declared its independence from Belgian reign in 1960 and the official languages are French, Lingala, Kikwana, Kikongo and Tshibula. On the Human Development Index (HDI), compiled by the UN Development Program, DR Congo comes in last. The climate is tropical with two seasons; rain season and dry season.The study was based on installing lighting that as many villagers as possible could benefit from. The lamps were installed in a paillote (hut) situated in the center of the village. Outdoor yard lamps and lighting inside the chief’s house were also installed. The system could power the lamps for five hours and charge up to eight phones in a day.Observations on the everyday life in the village was made, which included the baking of bread, cooking and the obtainment of water. Wind speeds were calculated, important distances were measured, and the villages documented. The purpose was to create a broad base for and encourage future development of the system as well as possible future projects.Many necessities were lacking in the village. Most of the people lived in huts made of mud, the cooking was done over fire and the baking of bread in clay ovens. The water was fetched from a water source situated at a 50 m height difference downhill from the village. The distance to the school was 2 km to which the children, who could afford it, walked every day. The wind speeds were estimated to be too low for the use of a wind turbine.

  • 2693.
    Ahmadian, Afshin
    KTH, Superseded Departments, Biotechnology.
    Approaches for analysis of mutations and genetic variations2001Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Detecting mutations and genomic variations is fundamental indiagnosis, isolating disease genes, association studies,functional genomics and pharmacogenomics. The objective hasbeen to use and further develop a variety of tools andtechnologies to analyze these genetic alterations andvariations.

    The p53 tumor suppressor gene and short arm of chromosome 9have been used as genetic markers to investigate fundamentalquestions concerning early events preceding non-melanoma skincancers, clonal progression and timing of different mutationsand deletions. Conventional gel based DNA sequencing andfragment analysis of microsatellite markers were utilized forthis purpose. In addition, a sequence-specific PCR-mediatedartifact is discussed.

    Pyrosequencing, a bioluminometric technique based onsequencing-by-synthesis, has been utilized to determinemutation ratios in the p53 gene. In addition, in the case ofmultiple mutations, pyrosequencing was adopted to determineallelic distribution of mutations without the use of cloningprocedures. Exons 5 to 8 of the p53 gene were also sequenced bythis method.

    The possibility of typing single base variations bypyrosequencing has been evaluated. Two different nucleotidedispensation orders were investigated and data were comparedwith the predicted pattern for each alternative of the variableposition. Analysis of loss of heterozygosity was possible byutilizing single nucleotide polymorphisms.

    A modified allele-specific extension strategy for genotypingof single nucleotide polymorphisms has been developed. Throughthe use of a real-time bioluminometric assay, it has beendemonstrated that reaction kinetics for a mismatchedprimer-template is slower than the matched configuration,butthe end-point signals are comparable. By introduction ofapyrase, the problems associated with mismatch extensions havebeen circumvented and accurate data has been obtained.

    Keywords:fragment analysis, microsatellite, loss ofheterozygosity, DNA sequencing, pyrosequencing, cancer,mutation, variation, single nucleotide polymorphism,allele-specific extension, bioluminescence, apyrase.

  • 2694.
    Ahmadian, Afshin
    et al.
    KTH, School of Biotechnology (BIO), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    AnderssonSvahn, Helene
    KTH, School of Biotechnology (BIO), Nano Biotechnology (closed 20130101). KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Massively parallel sequencing platforms using lab on a chip technologies2011In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 11, no 16, p. 2653-2655Article in journal (Refereed)
  • 2695.
    Ahmadian, Afshin
    et al.
    KTH, School of Biotechnology (BIO), Gene Technology.
    Ehn, M.
    Hober, Sophia
    KTH, School of Biotechnology (BIO), Proteomics.
    Pyrosequencing: History, biochemistry and future2006In: Clinica Chimica Acta, ISSN 0009-8981, E-ISSN 1873-3492, Vol. 363, no 02-jan, p. 83-94Article, review/survey (Refereed)
    Abstract [en]

    Background: Pyrosequencing is a DNA sequencing technology based on the sequencing-by-synthesis principle. Methods: The technique is built on a 4-enzyme real-time monitoring of DNA synthesis by bioluminescence using a cascade that upon nucleotide incorporation ends in a detectable light signal (bioluminescence). The detection system is based on the pyrophosphate released when a nucleotide is introduced in the DNA-strand. Thereby, the signal can be quantitatively connected to the number of bases added. Currently, the technique is limited to analysis of short DNA sequences exemplified by single-nucleotide polymorphism analysis and genotyping. Mutation detection and single-nucleotide polymorphisin genotyping require screening of large samples of materials and therefore the importance of high-throughput DNA analysis techniques is significant. In order to expand the field for pyrosequencing, the read length needs to be improved. Conclusions: Th pyrosequencing system is based on an enzymatic system. There are different current and future applications of this technique.

  • 2696.
    Ahmadian, Afshin
    et al.
    KTH, Superseded Departments, Biotechnology.
    Gharizadeh, B.
    Gustafsson, A. C.
    Sterky, Fredrik
    KTH, Superseded Departments, Biotechnology.
    Nyrén, Pål
    KTH, Superseded Departments, Biochemistry and Biotechnology.
    Uhlén, Mathias
    KTH, Superseded Departments, Biotechnology.
    Lundeberg, Joakim
    KTH, Superseded Departments, Biotechnology.
    Single-nucleotide polymorphism analysis by pyrosequencing2000In: Analytical Biochemistry, ISSN 0003-2697, E-ISSN 1096-0309, Vol. 280, no 1, p. 103-110Article in journal (Refereed)
    Abstract [en]

    There is a growing demand for high-throughput methods for analysis of single-nucleotide polymorphic (SNP) positions. Here, we have evaluated a novel sequencing approach, pyrosequencing, for such purposes. Pyrosequencing is a sequencing-by-synthesis method in which a cascade of enzymatic reactions yields detectable light, which is proportional to incorporated nucleotides. One feature of typing SNPs with pyrosequencing is that each allelic variant will give a unique sequence compared to the two other variants. These variants can easily be distinguished by a pattern recognition software. The software displays the allelic: alternatives and allows for direct comparison with the pyrosequencing raw data. For optimal determination of SNPs, various protocols of nucleotide dispensing order were investigated. Here, we demonstrate that typing of SNPs can efficiently be performed by pyrosequencing using an automated system for parallel analysis of 96 samples in approximately 5 min, suitable for large-scale screening and typing of SNPs.

  • 2697.
    Ahmadian, Afshin
    et al.
    KTH, Superseded Departments, Biotechnology.
    Gharizadeh, B.
    O'Meara, D.
    Odeberg, Jacob
    KTH, Superseded Departments, Biotechnology.
    Lundeberg, Joakim
    KTH, Superseded Departments, Biotechnology.
    Genotyping by apyrase-mediated allele-specific extension2001In: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 29, no 24Article in journal (Refereed)
    Abstract [en]

    This report describes a single-step extension approach suitable for high-throughput single-nucleotide polymorphism typing applications. The method relies on extension of paired allele-specific primers and we demonstrate that the reaction kinetics were slower for mismatched configurations compared with matched configurations. In our approach we employ apyrase, a nucleotide degrading enzyme, to allow accurate discrimination between matched and mismatched primer-template configurations. This apyrase-mediated allele-specific extension (AMASE) protocol allows incorporation of nucleotides when the reaction kinetics are fast (matched 3'-end primer) but degrades the nucleotides before extension when the reaction kinetics are slow (mismatched 3'-end primer). Thus, AMASE circumvents the major limitation of previous allele-specific extension assays in which slow reaction kinetics will still give rise to extension products from mismatched 3'-end primers, hindering proper discrimination. It thus represents a significant improvement of the allele-extension method. AMASE was evaluated by a bioluminometric assay in which successful incorporation of unmodified nucleotides is monitored in real-time using an enzymatic cascade.

  • 2698.
    Ahmadian, Afshin
    et al.
    KTH, Superseded Departments, Biotechnology.
    Lundeberg, Joakim
    KTH, Superseded Departments, Biotechnology.
    A brief history of genetic variation analysis2002In: BioTechniques, ISSN 0736-6205, E-ISSN 1940-9818, Vol. 32, no 5, p. 1122-+Article, review/survey (Refereed)
    Abstract [en]

    As the human genome sequence is determined, there is an emerging need for the analysis of human sequence variations as genetic markers in diagnosis, linkage and association studies, cancer research, and pharmacogenomics. There are several different techniques and approaches for detecting these genetic variations, and here we review some of these techniques and their application fields. However, all the techniques have advantages and disadvantages, and factors such as laboratory instrumentation, personnel experience, required accuracy, required throughput, and cost often have to be taken into account before selecting a method.

  • 2699.
    Ahmadian, Afshin
    et al.
    KTH, Superseded Departments, Biotechnology.
    Lundeberg, Joakim
    KTH, Superseded Departments, Biotechnology.
    Nyrén, Pål
    KTH, Superseded Departments, Biochemistry and Biotechnology.
    Uhlén, Mathias
    KTH, Superseded Departments, Biotechnology.
    Ronaghi, M.
    Analysis of the p53 tumor suppressor gene by pyrosequencing2000In: BioTechniques, ISSN 0736-6205, E-ISSN 1940-9818, Vol. 28, no 1, p. 140-+Article in journal (Refereed)
    Abstract [en]

    Tumor suppressor genes are implicated in cell cycle progression. Inactivation of these genes predominantly occurs through mutations and/or allelic loss that involves both alleles. With inactivation by multiple mutations in a single gene, cloning of the amplified gene is necessary to determine whether the mutations reside on one ol both alleles. Using pyrosequencing, a recently developed approach based on sequencing-by-synthesis, we studied genetic variability in the p53 tumor suppressor gene and could quantify the ratio between the mutated and wild-type amplified fragments. Further-more, this sequencing technique also allows allelic determination of adjacent mutations with no cloning of amplified fragments.

  • 2700. Ahmadian, Afshin
    et al.
    Pettersson, Erik
    Lundeberg, Joakim
    KTH, School of Biotechnology (BIO), Gene Technology.
    Method for amplification2005Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The invention refers to a method for multiplex amplification of at least one specific nucleic acid locus, comprising the steps of: providing at least one oligonucleotide probe pair that is designed so that the first and second probe of the pair anneal to a specific nucleic acid locus on a target molecule, in which pair the first probe has an extendable 3'-end, and a second probe has a 5'-end that is directly or indirectly labelled with a phosphate group; providing a target molecule comprising at least one specific nucleic acid locus; allowing the probe pair to anneal to the target molecule; allowing the 3'-end of the first probe to extend by influence of polymerase by adding a set of three different dNTPs; ligating the 3'-end of the extended first probe to the 5'-end of the second probe. Hereby, a method is provided which allows a high specificity for simultaneous amplification of several loci. Further, the invention involves a kit for use in the method of the invention.

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