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  • 51. Abbasalizadeh, A.
    et al.
    Sridar, S.
    Chen, Z.
    Sluiter, M.
    Yang, Y.
    Sietsma, J.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Hari Kumar, K. C.
    Experimental investigation and thermodynamic modelling of LiF-NdF3-DyF3 system2018In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 753, p. 388-394Article in journal (Refereed)
    Abstract [en]

    Electrolysis of molten fluorides is one of the promising methods for the recovery and recycling of rare earth metals from used magnets. Due to the dearth of phase equilibria data for molten fluoride systems, thermodynamic modelling of LiF-DyF3-NdF3 system using the CALPHAD approach was carried out. Gibbs energy modelling for LiF-NdF3 and LiF-DyF3 systems was performed using the constitutional data from literature. Ab initio calculations were used to obtain enthalpy of reaction of LiDyF4, an intermediate phase that is found to exist in the LiF-DyF3 system. Differential thermal analysis was carried out for selected compositions in the NdF3-DyF3 system, in order to determine liquidus and solidus temperatures. The Gibbs energy parameters for the limiting binaries determined in this work is used for modelling the Gibbs energy functions of equilibrium phases in the ternary system. Selected compositions of LiF-NdF3-DyF3 were subjected to DTA in order to validate the calculated phase temperatures involving melt.

  • 52. Abbasalizadeh, A.
    et al.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Sietsma, J.
    Yang, Y.
    Rare Earth Extraction from NdFeB Magnets and Rare Earth Oxides Using Aluminum Chloride/Fluoride Molten Salts2015In: Rare Earths Industry: Technological, Economic, and Environmental Implications, Elsevier, 2015, p. 357-373Chapter in book (Other academic)
    Abstract [en]

    In the current research, the feasibility of the recovery of neodymium and dysprosium from spent NdFeB magnets (about 6wt% Dy) was investigated using molten salt processes. The salt bath consisted of a eutectic composition of an NaCl-KCl-LiCl mixture. To enable the efficient dissolution of metal in the molten salt phase, AlCl3 was used as a chlorinating agent. Iron-free electrodeposition was carried out successfully. Energy-dispersive spectroscopic analysis of the electrodeposit revealed that co-deposition of the dysprosium occurs along with neodymium at the cathode. The process shows that this method is well suited for recovering rare earth metals from magnetic scrap containing these metals.Furthermore, the setup design for recovery of neodymium and dysprosium from their oxides was investigated with regard to previous studies on the neodymium magnets. The stability of different fluoride and chloride salts was studied by means of thermodynamic calculation. Aluminum fluoride-based molten salt systems were studied in detail as the electrolyte for electrochemical extraction of rare earth oxides into rare earth metal elements with Al.

  • 53. Abbasalizadeh, Aida
    et al.
    Malfliet, Annelies
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Sietsma, Jilt
    Yang, Yongxiang
    Electrochemical Extraction of Rare Earth Metals in Molten Fluorides: Conversion of Rare Earth Oxides into Rare Earth Fluorides Using Fluoride Additives2017In: JOURNAL OF SUSTAINABLE METALLURGY, ISSN 2199-3823, Vol. 3, no 3, p. 627-637Article in journal (Refereed)
    Abstract [en]

    In the present research on rare earth extraction from rare earth oxides (REOs), conversion of rare earth oxides into rare earth fluorides with fluoride fluxes is investigated in order to overcome the problem of low solubility of the rare earth oxides in molten fluoride salts as well as the formation of oxyfluorides in the fluorination process. Based on thermodynamic calculations, a series of experiments were performed for converting the rare earth oxides into rare earth fluorides using AlF3, ZnF2, FeF3, and Na3AlF6 as fluorinating agents in a LiF-Nd2O3 system. The formation of neodymium fluoride as a result of the reactions between these fluxes and neodymium oxide is confirmed. The rare earth fluoride thus formed can subsequently be processed through the electrolysis route in the same reactor, and rare earth metal can be produced as the cathodic deposit. In this concept, the REO dissolution in molten fluorides would become unnecessary due to the complete conversion of the oxide into the fluoride, REF3. The results of XRD and EPMA analysis of the reacted samples indicate that AlF3, ZnF2, and FeF3 can act as strong fluorinating agents for the neodymium oxide giving rise to a complete conversion of neodymium oxide into neodymium fluoride.

  • 54. Abbasalizadeh, Aida
    et al.
    Malfliet, Annelies
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Sietsma, Jilt
    Yang, Yongxiang
    Electrochemical Recovery of Rare Earth Elements from Magnets: Conversion of Rare Earth Based Metals into Rare Earth Fluorides in Molten Salts2017In: Materials transactions, ISSN 1345-9678, E-ISSN 1347-5320, Vol. 58, no 3, p. 400-405Article in journal (Refereed)
    Abstract [en]

    In the present work, selective extraction of rare earth (RE) metals from NdFeB magnets is investigated by studying the effects of various fluxes, viz. AlF3, ZnF2, FeF3 and Na3AlF6 in the LiF-NdFeB system. The aim is to convert RE from RE magnet into the fluoride salt melt. The results show the complete selective separation of neodymium (also dysprosium) from the magnet and formation of rare earth fluoride, leaving iron and boron unreacted. The formed rare earth fluoride can subsequently be processed in the same reactor through an electrolysis route so that RE can be deposited as a cathode product. The results of XRD and EPMA analysis of the reacted samples indicate that AlF3, ZnF2 and FeF3 can act as strong fluorinating agents for extraction of rare earth from NdFeB magnet, converting the RE to REF3. The results confirm the feasibility of the rare earth metals recovery from scrap NdFeB magnet as raw material. The fluoride conversion- electrolysis route suggested in the present work enables the extraction of rare earth metals in a single step using the above-mentioned fluxes.

  • 55.
    Abbasalizadeh, Aida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Sridhar, Seetharaman
    Grinder, Olle
    Izumi, Yukari
    Barati, Mansoor
    Highlights of the Salt Extraction Process2013In: JOM: The Member Journal of TMS, ISSN 1047-4838, E-ISSN 1543-1851, Vol. 65, no 11, p. 1552-1558Article in journal (Refereed)
    Abstract [en]

    This article presents the salient features of a new process for the recovery of metal values from secondary sources and waste materials such as slag and flue dusts. It is also feasible in extracting metals such as nickel and cobalt from ores that normally are difficult to enrich and process metallurgically. The salt extraction process is based on extraction of the metals from the raw materials by a molten salt bath consisting of NaCl, LiCl, and KCl corresponding to the eutectic composition with AlCl3 as the chlorinating agent. The process is operated in the temperature range 973 K (700 degrees C) to 1173 K (900 degrees C). The process was shown to be successful in extracting Cr and Fe from electric arc furnace (EAF) slag. Electrolytic copper could be produced from copper concentrate based on chalcopyrite in a single step. Conducting the process in oxygen-free atmosphere, sulfur could be captured in the elemental form. The method proved to be successful in extracting lead from spent cathode ray tubes. In order to prevent the loss of AlCl3 in the vapor form and also chlorine gas emission at the cathode during the electrolysis, liquid aluminum was used. The process was shown to be successful in extracting Nd and Dy from magnetic scrap. The method is a highly promising process route for the recovery of strategic metals. It also has the added advantage of being environmentally friendly.

  • 56. Abbasalizadeh, Aida
    et al.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Venkatesan, Prakash
    Sietsma, Jilt
    Yang, Yongxiang
    Novel Reactive Anode for Electrochemical Extraction of Rare Earth Metals from Rare Earth Oxides2017In: RARE METAL TECHNOLOGY 2017 / [ed] Kim, H Alam, S Neelameggham, NR Oosterhof, H Ouchi, T Guan, X, SPRINGER INTERNATIONAL PUBLISHING AG , 2017, p. 87-92Conference paper (Refereed)
    Abstract [en]

    Electrolytic production of metallic neodymium is carried out in fused fluoride salts containing neodymium oxide. Two major challenges pertaining to neodymium production are (a) low oxide solubility, (b) possibility of anodic fluorine gas evolution if the electrolysis rate exceeds feeding rate of neodymium oxide. In this study, a novel method is proposed in which iron fluoride (FeF3) is used as a fluorinating agent to convert neodymium oxide into neodymium fluoride. Electron Probe Micro Analysis (EPMA) results of as-converted salt show a complete conversion of neodymium oxide into neodymium fluoride. In the electrolysis process, iron is used as a reactive anode with electrochemical dissolution of iron into the melt, thus preventing fluorine gas evolution at the anode. Therefore, the fluorinating agent is constantly regenerated in situ which enables the continuous conversion of neodymium oxide feed. The cathodic product is a Nd-Fe alloy which can be directly used as a master alloy for the production of NdFeB permanent magnets.

  • 57.
    Abbasalizadeh, Aida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Seetharaman, S.
    Dysprosium extraction using molten salt process2014In: Rare metal technology 2014: proceedings of a symposium sponsored by The Minerals, Metals & Materials Society (TMS) held during TMS 2014, 143rd Annual Meeting & Exhibition, February 16-20, 2014, San Diego Convention Center, San Diego, California, USA, 2014, p. 207-208Conference paper (Refereed)
  • 58.
    Abbasalizadeh, Aida
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Sridhar, S.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Neodymium extraction using salt extraction process2015In: Transactions of the Institution of Mining and Metallurgy Section C - Mineral Processing and Extractive Metallurgy, ISSN 0371-9553, E-ISSN 1743-2855, Vol. 124, no 4, p. 191-198Article in journal (Refereed)
    Abstract [en]

    The present paper deals with the feasibility of the neodymium recovery from spent Nd-Fe-B magnets using molten salt electrodeposition method. The salt bath consisted of a mixture of LiCl- KCl-NaCl corresponding to the eutectic composition. The experimental set-up with its salient features is presented. AlCl3 was used as flux and graphite rods dipped in the salt bath served as electrodes. The voltage for the electrolysis was chosen on the basis of the decomposition potential of NdCl3. The reaction sequence can be described as Iron-free neodymium deposition could be carried out successfully. In view of the proximity of the electrode potentials, the co-deposition of the aluminium and neodymium was observed to occur at the cathode, as revealed by SEM/EDS and XRD analyses of the electrodeposit.

  • 59. Abbasi, A. G.
    et al.
    Muftic, Sead
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Schmölzer, Gernot
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    A model and design of a security provider for Java applications2009In: International Conference for Internet Technology and Secured Transactions, ICITST 2009, 2009, p. 5402592-Conference paper (Refereed)
    Abstract [en]

    The model and design of a generic security provider provides a comprehensive set of security services, mechanisms, encapsulation methods, and security protocols for Java applications. The model is structured in four layers; each layer provides services to the upper layer and the top layer provide services to applications. The services reflect security requirements derived from a wide range of applications; from small desktop applications to large distributed enterprise environments. Based on the abstract model, this paper describes design and implementation of an instance of the provider comprising various generic security modules: symmetric key cryptography, asymmetric key cryptography, hashing, encapsulation, certificates management, creation and verification of signatures, and various network security protocols. This paper also describes the properties extensibility, flexibility, abstraction, and compatibility of the Java Security Provider.

  • 60. Abbasi, A. G.
    et al.
    Muftic, Sead
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Schmölzer, Gernot
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    CryptoNET: A model of generic security provider2010In: International Journal of Internet Technology and Secured Transactions, ISSN 1748-569X, E-ISSN 1748-5703, Vol. 2, no 3-4, p. 321-335Article in journal (Refereed)
    Abstract [en]

    The model and design of a generic security provider provides a comprehensive set of security services, mechanisms, encapsulation methods, and security protocols for Java applications. The model is structured in four layers; each layer provides services to the upper layer and the top layer provide services to applications. The services reflect security requirements derived from a wide range of applications; from small desktop applications to large distributed enterprise environments. Based on the abstract model, this paper describes design and implementation of an instance of the provider comprising various generic security modules: symmetric key cryptography, asymmetric key cryptography, hashing, encapsulation, certificates management, creation and verification of signatures, and various network security protocols. This paper also describes the properties for extensibility, flexibility, abstraction, and compatibility of the Java security provider.

  • 61.
    Abbasi, Abdul Ghafoor
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Muftic, Sead
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Mumtaz, Shahzad Ahmed
    KTH, School of Information and Communication Technology (ICT), Communication: Services and Infrastucture (Closed 20120101), Communication Systems, CoS (closed 2012-01-01).
    Security extensions of windows environment based on FIPS 201 (PIV) smart card2011In: World Congr. Internet Secur., WorldCIS, 2011, p. 86-92Conference paper (Refereed)
    Abstract [en]

    This paper describes security extensions of various Windows components based on usage of FIPS 201 (PIV) smart cards. Compared to some other similar solutions, this system has two significant advantages: first, smart cards are based on FIPS 201 standard and not on some proprietary technology; second, smart card security extensions represent an integrated solution, so the same card is used for security of several Microsoft products. Furthermore, our smart card system uses FIPS 201 applet and middleware with smart card APIs, so it can also be used by other developers to extend their own applications with smart card functions in a Windows environment. We support the following security features with smart cards: start-up authentication (based on PIN and/or fingerprint), certificate-based domain authentication, strong authentication, and protection of local resources. We also integrated our middleware and smart cards with MS Outlook and MS Internet Explorer.

  • 62. Abbasi Hoseini, A.
    et al.
    Lundell, Fredrik
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Andersson, H. I.
    Finite-length effects on dynamical behavior of rod-like particles in wall-bounded turbulent flow2015In: International Journal of Multiphase Flow, ISSN 0301-9322, E-ISSN 1879-3533, Vol. 76, p. 13-21Article in journal (Refereed)
    Abstract [en]

    Combined Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV) measurements have been performed in dilute suspensions of rod-like particles in wall turbulence. PIV results for the turbulence field in the water table flow apparatus compared favorably with data from Direct Numerical Simulations (DNS) of channel flow turbulence and the universality of near-wall turbulence justified comparisons with DNS of fiber-laden channel flow. In order to examine any shape effects on the dynamical behavior of elongated particles in wall-bounded turbulent flow, fibers with three different lengths but the same diameter were used. In the logarithmic part of the wall-layer, the translational fiber velocity was practically unaffected by the fiber length l. In the buffer layer, however, the fiber dynamics turned out to be severely constrained by the distance z to the wall. The short fibers accumulated preferentially in low-speed areas and adhered to the local fluid speed. The longer fibers (l/z > 1) exhibited a bi-modal probability distribution for the fiber velocity, which reflected an almost equal likelihood for a long fiber to reside in an ejection or in a sweep. It was also observed that in the buffer region, high-speed long fibers were almost randomly oriented whereas for all size cases the slowly moving fibers preferentially oriented in the streamwise direction. These phenomena have not been observed in DNS studies of fiber suspension flows and suggested l/z to be an essential parameter in a new generation of wall-collision models to be used in numerical studies.

  • 63.
    Abbasi, Mahmoud
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.
    Synthesis and characterization of magnetic nanocomposite of chitosan/SiO2/carbon nanotubes and its application for dyes removal2017In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 145, p. 105-113Article in journal (Refereed)
    Abstract [en]

    The adsorption characteristics of Direct Blue 71 (DB71) and Reactive Blue 19 (RB19) from aqueous solution onto novel magnetic nanocomposite of Chitosan/SiO2/CNTs (MNCSC) have been investigated. The morphology of MNCSC was characterized by vibrating sample magnetometer (VSM), field-emission scanning electron microscopy (FESEM), X-ray Diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The effect of initial dye concentration, contact time, adsorbent dosage and initial pH as experimental parameters on the removal of dyes were investigated. The adsorption experiments indicated the maximum adsorption capacity occurred at pH 6.8 for DB71 and pH 2.0 for RB19. The experimental data were analyzed by isotherm models and equilibrium results were fitted well with the Langmuir isotherm model and the maximum adsorption capacity of the MNCSM was determined to be 61.35 mg/g for DB71 (R-2 = 0.996) and 97.08 mg/g for RB19 (R-2 = 0.998). Adsorption data were analyzed with three kinetics models and pseudo second-order equation could best describe for adsorption of dyes. Finally, the thermodynamic parameters were determined. (C) 2017 Elsevier Ltd. All rights reserved.

  • 64.
    Abbasi, Mazhar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Dawit Ghebreigziabher, Kibret
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Objektklassificerad modellering och effektivisering avmängduttag2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The lack of fluent communication in the building industry has caught people’s attention because of

    time-based costs appearing in 2D and 3D modelling and takeoffs. These costs emerge in construction

    when miscommunication takes place between professionals in different projects.

    A research study of the subject has revealed the reason behind the current days’ miscommunication

    issues. The study shows that although the professionals tend to have an efficient way of working, the

    result isn’t very beneficial for the next man. Therefore a conclusion of the issue creates a demand for a

    mutual language in modelling and better softwares for takeoffs.

    This report’s results, with regards to optimization of modeling, has brought to light the use for the

    objectclassificationsystem BIP. These BIP-codes are used for branding objects in models of which the

    branding consists of unique codes. The code of every individual object has the purpose of being

    recognized by every project member and remain the same throughout the project.

    The proposal for the optimization of takeoffs is a software called VICO Office. The software contains

    well-advised methods for the import of models and close to automated takeoffs of these models.

    In conclusion, the study implies that there is sufficient motive to question the old ways of working and

    that light should be shed on new approaches. Technology and the industry face a constant change and

    the efficiency of current methods are never far away.

  • 65.
    Abbasi, Mozaffer
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Analys och implementering av VSL-System i FEM-Design för kontroll av stabiliserande effekt: En undersökning i syfte att fastlägga effekten av VSL-kablar i FEM-Design för att utvärdera dess stabiliserande påverkan.2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 66.
    ABBASI, MUHAMMAD MOHSIN
    KTH, School of Electrical Engineering (EES), Signal Processing.
    Solving Sudoku by Sparse Signal Processing2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sudoku is a discrete constraints satisfaction problem which is modeled as an underdetermined linear

    system. This report focuses on applying some new signal processing approaches to solve sudoku and

    comparisons to some of the existing approaches are implemented. As our goal is not meant for

    sudoku only in the long term, we applied approximate solvers using optimization theory methods. A

    Semi Definite Relaxation (SDR) convex optimization approach was developed for solving sudoku. The

    idea of Iterative Adaptive Algorithm for Amplitude and Phase Estimation (IAA-APES) from array

    processing is also being used for sudoku to utilize the sparsity of the sudoku solution as is the case in

    sensing applications. LIKES and SPICE were also tested on sudoku and their results are compared with

    l1-norm minimization, weighted l1-norm, and sinkhorn balancing. SPICE and l1-norm are equivalent

    in terms of accuracy, while SPICE is slower than l1-norm. LIKES and weighted l1-norm are equivalent

    and better than SPICE and l1-norm in accuracy. SDR proved to be best when the sudoku solutions are

    unique; however the computational complexity is worst for SDR. The accuracy for IAA-APES is

    somewhere between SPICE and LIKES and its computation speed is faster than both.

  • 67.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A comparison between particle characteristics between two railway brake pads2013Report (Other academic)
  • 68.
    Abbasi, Saeed
    Sharif university of Technology, Iran.
    A feasibilty study to establish freight cars overhaul center (Master thesis), Sharif university of technology2005Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
  • 69.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A study of nanostructured particles in railway tunnels2013Report (Other academic)
  • 70.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Characterisation of airborne particles from rail traffic2011Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Since the investigation of wear particles in rail transport started in late-1910s, the high mass concentration of these particles has raised worries among researchers concerned with air quality. However, effective action has yet to be taken because of lack of relevant knowledge. This thesis provides applicable information for the airborne wear particles in rail transport. Some aspects of their characteristics such as diameter size, mass concentration, number concentration, and morphology of particles were investigated in field tests and laboratory tests.The effects on particle characterisations from different operational conditions in the field tests, and applying different braking materials, conducting tests in different applied loads or sliding velocities in the laboratory tests were studied. The main advantage of conducting laboratory tests was to focus on studying particles from one source. The possibility of repetition, using high sensitive instruments and conducting tests at low costs are the other advantages of laboratory studies. Paper A describes how a pin-on-disc machine was used to reproduce similar real operational conditions during mechanical braking in a train. The results were validated by comparing the field tests results with the laboratory studies. The particles morphology and size distribution were also studied.Paper B presents a summary of field tests results. The effects of curve negotiating and applying braking in different real conditions were investigated with an on-board measurement.The element composition of the particles and their potential sources were also investigated outside of the particles morphologies.Paper C presents comprehensive results from laboratory studies on airborne particles from different braking materials. The differences in the particle characteristics in similar test conditions were attributable to different material compositions and dominant wear mechanisms. A new index was introduced in this paper and is suggested to be used as a qualitative factor with regard to the airborne wear particle emission rate.Paper D is a review of the recent studies of exhaust emission and non-exhaust emission from rail vehicles. A summary of results, measurements, adverse health effects, and proposed or applied solutions are reviewed in this paper.

  • 71. Abbasi, Saeed
    Implementing theory of constraint in choosing six sigma project2008Conference paper (Refereed)
  • 72.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Nanostructured particles in/outside compartment of running train, an on board measurement2013Report (Other academic)
  • 73.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Non-exhaust Nano particle emission in Rail traffic2010Conference paper (Refereed)
  • 74.
    Abbasi, Saeed
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Towards elimination of airborne particles from rail traffic2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Since the investigation of wear particles from rail transport started in the late 1910s, the high mass concentrations of these particles have prompted concern among researchers interested in air quality. However, effective action has yet to be taken because relevant knowledge is still missing. This thesis provides knowledge of airborne wear particles originating from rail transport. Some aspects of their characteristic parameters, such as size, mass concentration, number concentration, and morphology, were investigated in the field and in laboratory tests. We also discuss means to mitigate non-exhaust emissions, as well as the advantages and disadvantages of various test set-ups in the seven appended journal papers:Paper A reviews recent studies of exhaust and non-exhaust emissions from rail vehicles. The results, measurements, adverse health effects, and proposed or applied solutions presented in this literature are summarized in this paper.Paper B summarizes the results of field tests we conducted. The effects of curve negotiation and braking under different real conditions were investigated in a field test in which on-board measurements were made. The elemental composition and morphology of the particles emitted and their potential sources were also investigated.Paper C describes how a pin-on-disc machine can be used to reproduce real operating conditions during mechanical train braking in a controlled laboratory setting. The results were validated by comparing the field test results with the results of laboratory studies.Paper D presents comprehensive results of laboratory studies of airborne particles from different braking materials. A new index is introduced in this paper, which can be used as a quantitative metric for assessing airborne wear particle emission rates.Paper E describes the effects of using various friction modifiers and lubricants on the characteristics of airborne particles from wheel–rail contact under lubricated and unlubricated conditions.Paper F reports work to simulate thermoelastic instability in the cast-iron braking material. We simulated the fluctuation of the flash temperature by considering the temperature dependency of the material properties and the transformation of the contact state due to thermomechanical phenomena and wear.Paper G reviews new full- and sub-scale measurements of non-exhaust emissions from ground transport. The advantages and disadvantages of on-board measurements, pin-on-disc tests, dynamometer tests, and test rig studies are discussed in this paper.

  • 75. Abbasi, Saeed
    Utilizing the integrated six sigma and lean methodology2008Conference paper (Other academic)
  • 76.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Ekstrand-Hammarström, Barbara
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI),.
    Bergström, Ulrika
    Division of CBRN Defence and Security, Swedish Defence Research Agency (FOI),.
    Bucht, Anders
    Deptartment of Public Health and Clinical Medicine, Umeå University Hospital, Umeå, 901 89, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Jansson, Anders
    Department of Applied Environmental Science, Stockholm University, Stockholm, 106 91, Sweden.
    Biological response in lung cells by brake dust from a novel set-up to generate one sourcewear particles2013Conference paper (Refereed)
  • 77.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Jansson, Anders
    Stockholm University, Applied Environmental Science, Stockholm, Sweden.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A pin-on-disc study of the rate of airborne wear particle emissions from railway braking materials2012In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 284, p. 18-29Article in journal (Refereed)
    Abstract [en]

    The current study investigates the characteristics of particles generated from the wear of braking materials, and provides an applicable index for measuring and comparing wear particle emissions. A pin-on-disc tribometer equipped with particle measurement instruments was used. The number concentration, size, morphology, and mass concentration of generated particles were investigated and reported for particles 10 nm-32 mu m in diameter. The particles were also collected on filters and investigated using EDS and SEM. The effects of wear mechanisms on particle morphology and changes in particle concentration are discussed. A new index, the airborne wear particle emission rate (AWPER), is suggested that could be used in legislation to control non-exhaust emissions from transport modes, particularly rail transport.

  • 78.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Jansson, Anders
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Particle emissions from rail traffic: a literature review2013In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 43, no 23, p. 2211-2244Article, review/survey (Refereed)
    Abstract [en]

    Particle emissions are a drawback of rail transport. This work is a comprehensive presentation of recent research into particle emissions from rail vehicles. Both exhaust and non-exhaust particle emissions are considered when examining particle characteristics such as  PM10, and PM2.5 concentration levels, size, morphology, composition, as well as adverse health effects, current legislation, and available and proposed solutions for reducing such emissions. High concentration levels in enclosed rail traffic environments are reported and some toxic effects of the particles. We find that only a few limited studies have examined the adverse health effects of non-exhaust particle emissions and that no relevant legislation exists. Thus further research in this area is warranted.

  • 79.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Moslemi, Kianoush
    A new approach for optimization of heating system in tank wagons2003Conference paper (Refereed)
  • 80.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.
    Larsson, Christina
    Bombardier Transportation Sweden AB, Västerås, Sweden.
    Jansson, Anders
    Stockholm University, Applied Environmental Science, Stockholm, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A field test study of airborne wear particles from a running regional train2012In: IMechE, Part F: Journal of Rail and Rapid Transit, ISSN 0954-4097, Vol. 226, no 1, p. 95-109Article in journal (Refereed)
    Abstract [en]

    Inhalable airborne particles have inverse health affect. In railways, mechanical brakes, the wheel–rail contact, current collectors, ballast, sleepers, and masonry structures yield particulate matter. Field tests examined a Swedish track using a train instrumented with particle measurement devices, brake pad temperature sensors, and speed and brake sensors. The main objective of this field test was to study the characteristics of particles generated from disc brakes on a running train with an on-board measuring set-up.

    Two airborne particle sampling points were designated, one near a pad–rotor disc brake contact and a second under the frame, not near a mechanical brake or the wheel–rail contact; the numbers and size distributions of the particles detected were registered and evaluated under various conditions (e.g. activating/deactivating electrical brakes or negotiating curves). During braking, three speed/temperature-dependent particle peaks were identified in the fine region, representing particles 280 nm, 350 nm, and 600 nm in diameter. In the coarse region, a peak was discerned for particles 3–6 μm in diameter. Effects of brake pad temperature on particle size distribution were also investigated. Results indicate that the 280 nm peak increased with increasing temperature, and that electrical braking significantly reduced airborne particle numbers. FESEM images captured particles sizing down to 50 nm. The ICP-MS results indicated that Fe, Cu, Zn, Al, Ca, and Mg were the main elements constituting the particles.

     

  • 81.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A study of friction modifiers on airborne wear particles from wheel-rail contact2012Conference paper (Refereed)
    Abstract [en]

    Wheel-rail contact and its wear process are crucial issues in maintenance and operating of rolling stocks. During wheel-rail contact, materials in mating faces are worn off and some of them transferred to airborne particles. Eventhough the wear process in wheel-rail contact are well-known, few studies have been conducted on the airborne particles from wheel-rail contact.

    The purpose of this study is to investigate the effect of using different friction modifier on the amount of airbotne particles from wheel-rail contact in a laboratory simulation. In this regard, a series laboratory tests were used by using round head pin (R=25mm) and dead weight 40 N in a pin-on-disc machine. This set-up simulates a contact pressure around 750 MPa on the pin head.

    The amount of airborne particles and their characteristics were investigated in dry-contact, and non-dry contacts whereas a lubricant, Binol rail 510 and a friction modifier, tramsilence were used. According to the results, the effects of using Binol rail to reduce the amount of airborne particles were considerable.

  • 82.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Airborne wear particles from train traffic2010Conference paper (Refereed)
  • 83.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Experiences of measuring airborne wear particles from braking materials and the wheel - Rail contact2012In: 9th International Conference on Contact Mechanics and Wear of Rail/Wheel Systems, CM 2012, Southwest Jiaotong University , 2012, p. 608-609Conference paper (Refereed)
    Abstract [en]

    During braking both of the discs and pads of disc brakes are worn. Since disc brakes are not sealed, some of the generated wear particles can become airborne. The same condition also holds for block brakes utilized in rail vehicles. Furthermore, the wheel-rail contact is also subjected to wear processes during braking as well as during normal running. This contact also contributes to generation of airborne particles. Several studies have found an association between adverse health effects and the concentration of particles in the atmosphere, so it is of interest to improve our knowledge of the airborne wear particles. The present work includes results from full scale testing of rail vehicles. Particle size distribution, morphology and elemental contents are presented and discussed. Due to high back ground concentration levels in field tests, dedicated laboratory test set ups on a reduced scale were designed and utilized for airborne particle studies with zero background level. Promising correlation between field test and the lab set up is identified. Different ways of using this test set up for evaluating how the composition of the airborne particles is classified with respect to their health effects are discussed. Furthermore, different ways of using the proposed method to rank and to quantify airborne particle emission factors are presented.

  • 84.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Experiences of measuring airborne wear particles from braking materials and wheel-rail contact2012Conference paper (Refereed)
    Abstract [en]

    During braking both of the discs and pads of disc brakes are worn. Since disc brakes are not sealed, some of the generated wear particles can become airborne.  Wheel-rail is also subjected to wear process during braking as well as normal running. They also contribute to generate airborne particles. Several studies have found an association between adverse health effects and the concentration of particles in the atmosphere, so it is of interest to improve our knowledge of the airborne wear particles generated by disc brakes.

    The present work includes results from full scale testing of rail vehicles. Particle size distribution, morphology and elemental contents are presented and discussed for different combinations of disc and pad materials. Due to high back ground concentration levels in field tests, dedicated laboratory test set ups on a reduced scale were designed and utilized for airborne particle studies with zero background level.

    Promising correlation between field test and the lab set up is identified. Different ways of using this test set up for evaluating how the composition of the airborne particles is classified with respect to their health effects are discussed. Furthermore, different ways of using the proposed method to rank and to quantify airborne particle emission factors are presented.

  • 85.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Lack of applicable criteria in non-exhaust emission legislation: AWPER index a practical solution2011Conference paper (Refereed)
  • 86.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olander, Lars
    A field investigation of the size and morphology and chemical composition of airborne particles in rail transport2010Conference paper (Refereed)
  • 87.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olander, Lars
    Larsson, christina
    A field investigation of the size, morphology and chemical composition of airborne particles in rail transport2010Conference paper (Refereed)
    Abstract [en]

    The health effects of inhalable airborne particles are well documented. In the European Union the European Council mandates that the level of airborne particles with a diameter smaller than 10 µm (PM10) must not exceed an annual average of 40 µg/m3. Examples of possible sources from rail transport are mechanical brakes, wheel rail contact, current collectors, ballast, sleepers and masonry structures. In this regard, a series of field tests have been conducted on a regular Swedish track using a regional train instrumented with: particle measurement devices, temperature sensors in brake pads and sensors to measure the magnitude of train speed and a GPS.

    Two sampling points for airborne particles were designated in the train under frame. One of the sampling points was near a pad to rotor disc brake contact and a second global sampling point was chosen under the frame, but not near a mechanical brake or the wheel-rail contact. The first one was highly influenced by brake pad wear debris and the other one was influenced by all of the brake pads, wheel and rail wear debris as well as re-suspension. In each sampling points, three tubes were linked to three particle measurement devices. Two sets of Ptrak, Dustrak and Grimm devices were used. The Ptrak 8525 was an optical particle measurement device which could measure particle diameter in the size interval of 20 nm up to 1 micrometer. The Dustrak was used to measure particle mass concentration. The Grimm 1.109 was an aerosol spectrometer which counted number of particles from 0.25 micrometer to 32 micrometer in 31 intervals. These two Grimm devices were equipped with Millipore filters in the devices outlets to capture particles for further studies on morphology and matter of particles.

    The total number and size distribution of the particles for these two sampling points were registered and evaluated in different situations such as activating and deactivating electrical brake or train curve negotiating.

    During braking, three peaks of 250 nm, 350 nm and 600 nm in diameter, with the 350 nm peak dominating were identified in the fine particle region. In the coarse particle region, a peak of around 3-6 µm in diameter was discovered. The brake pad temperature effects on particle size distribution were also investigated and the results showed that the peak around 250 nm increased. Furthermore, the activation of electrical braking significantly reduced the number of airborne particles.

    A SEM was used to capture the images from collected particles on filters. Furthermore, an ICP-Ms method was used to investigate the elemental contents of the particulates on the filter.  In this case the main contribution belonged to Fe, Si, Al, Ca, Cu, Zn. The higher amount of some elements weights such as calcium, silicon, sodium and aluminum in the global sampling point filters revealed that ballast and concrete sleepers were the main sources for these particles although some of them originated from rail, wheel, brake disc and brake pad as well.

  • 88.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Tritscher, Trosten
    TSI.
    Krinke, Thomas
    TSI.
    On-board study of nano- and micrometer-particle characteristics of a running electric train2013Conference paper (Refereed)
  • 89.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Zhu, Yi
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Pin-on-disc study of the effects of railway friction modifiers on airborne wear particles from wheel-rail contact2013In: Tribology International, ISSN 0301-679X, E-ISSN 1879-2464, Vol. 60, p. 136-139Article in journal (Refereed)
    Abstract [en]

    Knowledge of wheel–rail interaction is crucial to wheel and rail maintenance. In this interaction, some of theworn-off material is transformed into airborne particles. Although such wear is well understood, few studiestreat the particles generated. We investigated friction modifiers' effects on airborne particles characteristicsgenerated in wheel-rail contacts in laboratory conditions. Pin-on-disc machine testing with a round-head pinloaded by a dead weight load 40 N simulated maximum contact pressure over 550 MPa. Airborne particlecharacteristics were investigated in dry contacts and in ones lubricated with biodegradable rail grease andwater- and oil-based friction modifiers. The number of particles declined with the grease; the number ofultrafine particles increased with the water-based friction modifier, mainly due to water vaporization.

  • 90.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Particle emission from rail vehicles: A literature review2012In: Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, Sage Publications, 2012Conference paper (Refereed)
    Abstract [en]

    Emission of airborne particles is a side effect from rail transport. This work reviews recent research on particle emissions from rail vehicles. Both exhaust and non-exhaust particle emissions are characterized by size, morphology, composition, and size distribution. Current legislation, knowledge of adverse health effects, and available and proposed solutions for emission reductions are also treated. There has been much focus on exhaust emissions, but only a few limited studies have investigated non-exhaust particle emissions, which contain a significant amount of metallic materials. A new method for measuring the airborne wear particle emission rate (AWPER) is proposed as a first step to guide new legislations and to focus further research on non-exhaust airborne emission, i.e., research on the generation mechanisms for particle emissions and their adverse health effects.

  • 91.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Technical note: Experiences of studying airborne wear particles from road and rail transport2013In: Aerosol and Air Quality Research, ISSN 1680-8584, Vol. 13, no 4, p. 1161-1169Article in journal (Refereed)
    Abstract [en]

    Airborne particles and their adverse effects on air quality have been recognized by humans since ancient times. Current exhaust emission legislations increase the relative contribution of wear particles on the PM levels. Consequently, wearbased particle emissions from rail and road transport have raised concerns as ground transportation is developing quickly. Although scientific research on airborne wear-based particles started in 1909, there is almost no legislation that control the generation of wear-based particles. In addition, there is no accepted and approved standard measurement technique for monitoring and recording particle characteristics. The main objective of this study is to review recent experimental work in this field and to discuss their set-ups, the sampling methods, the results, and their limitations, and to propose measures for reducing these limitations.

  • 92.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. Department of Mechanical engineering, Golpayegan University of Technology.
    Teimourimanesh, Shahab
    Chalmers.
    Vernersson, Tore
    Chalmers.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Lunden, Roger
    Chalmers.
    Temperature and Thermoelastic Instability at Tread Braking Using Cast Iron Friction Material2013In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 314, no 1–2, p. 171-180Article in journal (Refereed)
    Abstract [en]

    Braking events in railway traffic often induce high frictional heating and thermoelastic instability (TEI) at the interfacing surfaces. In the present paper, two approaches are adopted to analyse the thermomechanical interaction in a pin-on-disc experimental study of railway braking materials. In a first part, the thermal problem is studied to find the heat partitioning between pin and disc motivated by the fact that wear mechanisms can be explained with a better understanding of the prevailing thermal conditions. The numerical model is calibrated using the experimental results. In a second part, the frictionally induced thermoelastic instabilities at the pin-disc contact are studied using a numerical method and comparing them with the phenomena observed in the experiments. The effects of temperature on material properties and on material wear are considered. It is found from the thermal analysis that the pin temperature and the heat flux to the pin increase with increasing disc temperatures up to a transition stage. This agrees with the behaviour found in the experiments. Furthermore, the thermoelastic analysis displays calculated pressure and the temperature distributions at the contact interface that are in agreement with the hot spot behaviour observed in the experiments.

  • 93.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Teimourimanesh, Shahab
    Chalmers.
    Vernersson, Tore
    Chalmers.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements. KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group.
    Lunden, Roger
    Chalmers.
    Temperature and thermo-elastic instability of tread braking friction materials2012Conference paper (Refereed)
  • 94.
    Abbasi, Saeed
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Wahlström, Jens
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    Olander, Lars
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Services Engineering.
    Larsson, Christina
    Bombardier Transportation Sweden AB, Västerås, Sweden.
    Olofsson, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Tribologi.
    Sellgren, Ulf
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Machine Elements.
    A study of airborne wear particles generated from organic railway brake pads and brake discs2011In: Wear, ISSN 0043-1648, E-ISSN 1873-2577, Vol. 273, no 1, p. 93-99Article in journal (Refereed)
    Abstract [en]

    Brake pads on wheel-mounted disc brakes are often used in rail transport due to their good thermal properties and robustness. During braking, both the disc and the pads are worn. This wear process generates particles that may become airborne and thus affect human health. The long term purpose of ‘Airborne particles in Rail transport’ project is to gain knowledge on the wear mechanisms in order to find means of controlling the number and size distribution of airborne particles. In this regard, a series of full-scale field tests and laboratory tests with a pin-on-disc machine have been conducted. The morphology and the matter of particles, along with their size distribution and concentration, have been studied. The validity of results from the pin-on-disc simulation has been verified by the field test results. Results show an ultra-fine peak for particles with a diameter size around 100 nm in diameter, a dominant fine peak for particles with a size of around 350 nm in diameter, and a coarse peak with a size of 3-7 μm in diameter. Materials such as iron, copper, aluminium, chromium, cobalt, antimony, and zinc have been detected in the nano-sized particles.

  • 95.
    Abbasiverki, Roghayeh
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Analysis of underground concrete pipelines subjected to seismic high-frequency loads2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Buried pipelines are tubular structures that are used for transportation of important liquid materials and gas in order to provide safety for human life. During an earthquake, imposed loads from soil deformations on concrete pipelines may cause severe damages, possibly causing disturbance in vital systems, such as cooling of nuclear power facilities. The high level of safety has caused a demand for reliable seismic analyses, also for structures built in the regions that have not traditionally been considered as highly seismically active. The focus in this study is on areas with seismic and geological conditions corresponding to those in Sweden and Northern Europe. Earthquakes in Sweden for regions with hard rock dominated by high-frequency ground vibrations, Propagation of such high-frequency waves through the rock mass and soil medium affect underground structures such as pipelines.

    The aim of this project is investigating parameters that affect response of buried pipelines due to high-frequency seismic excitations. The main focus of the study is on reinforced concrete pipelines. Steel pipelines are also studied for comparison purposes. The effects of water mass, burial depth, soil layer thickness and non-uniform ground thickness caused by inclined bedrock are studied. The results are compared to those obtained for low-frequency earthquakes and the relationship between strong ground motion parameters and pipelines response is investigated. It is shown that, especially for high frequency earthquake excitations, non-uniform ground thickness due to inclined bedrock significantly increase stresses in the pipelines. For the conditions studied, it is clear that high-frequency seismic excitation is less likely to cause damage to buried concrete pipelines. However, the main conclusion is that seismic analysis is motivated also for pipelines in high-frequency earthquake areas since local variation in the ground conditions can have a significant effect on the safety.

  • 96.
    Abbasiverki, Roghayeh
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Initial study on seismic analyses of concrete and embankment dams in Sweden2017Report (Other academic)
  • 97.
    Abbasiverki, Roghayeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Analysis of buried reinforced concrete pipelines subjected to seismic waves2014Conference paper (Refereed)
  • 98.
    Abbasiverki, Roghayeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Seismic response of buried concrete pipelines subjected to highfrequency earthquakesIn: Geotechnical and Geological Engineering, ISSN 0960-3182, E-ISSN 1573-1529Article in journal (Refereed)
    Abstract [en]

    Buried pipelines are tubular structures that cross large areas with different geological conditions. During an earthquake, imposed loads from soil deformations on concrete pipelines may cause severe damages. In this study, the use of two-dimensional finite element models of pipelines and surrounding soil for simulation of seismic waves that propagate from the bedrock through the soil are demonstrated. The models describe both longitudinal and transverse cross-sections of pipelines and the soil-pipe interaction is modelled as a nonlinear behaviour. The effects of uniform ground with different burial depths, soil layer thickness, soil stiffness and bedrock geometry on the seismic response of reinforced concrete pipelines is studied. Two earthquakes, with high and low frequency contents, are employed for the dynamic analysis. The results show that there is a much smaller risk of damage from high-frequency earthquakes, but that there is a significant effect on the response due to possible irregular ground with inclined bedrock.

  • 99.
    Abbasiverki, Roghayeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Ansell, Anders
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Malm, Richard
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Concrete Structures.
    Analysis of shallowly buried reinforced concrete pipelines subjected to earthquake loads2014In: Nordic Concrete Research, ISSN 0800-6377, no 51, p. 111-130Article in journal (Refereed)
    Abstract [en]

    Buried reinforced concrete pipelines are widelyused in e.g. water and wastewater systems. Failure of these infrastructures mayresult in drastic effects and recently they have been brought into focus asvital components in safety systems for nuclear power installations. The highlevel of safety has here lead to a demand for reliable earthquake risk analyses.In this paper, methods are compared and the use of seismic design loadsdemonstrated. FE analysis in 2D of soil-pipe interaction under seismic wavepropagation is performed. The performance of concrete pipes subjected toseismic waves with different frequency content is evaluated with respect todifferent soil condition but also water mass effect.

  • 100.
    Abbassi, Behrang
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Hultling, Johannes
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Smarta Elnät – Modell och Marknad2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Smart Grid technology has during the last decade been established as a way to create a greater flexibility on the electricity grid that will be needed as the development moves towards an increased share of renewable primary energy sources in the electricity production. One part of the Smart Grid technology is the ability to shift loads in time, to adapt to either price or emissions, known as Demand Response. This project, which was conducted at KTH in collaboration with the consulting corporation Capgemini, examines the economic, environmental and social aspects of the Demand Response technology.

     

    In the project, three household products are used in a model that derives the potential savings in costs and emissions of CO2e. The results show that the actual savings measured in SEK are small, but that the savings measured in percent can be as high as 20 percent. Reduction of CO2e emissions is slightly lower. Furthermore, the study shows that the savings increase as more flexibility is given to the model and as the fluctuations of price increases. A scenario that includes more intermittent electricity production, and end users ready to commit to the technology,  is therefore vital for the success of the Demand Response technology. The results also show that an optimization cannot be done in such way that both minimize costs and CO2e emissions simultaneously.

     

    A discussion on the strategic opportunities for Capgemini shows that focus should be on collecting, interpreting and compiling the large amounts of data that the technology will result in. There are also possibilities in peripheral services tied together with the Smart Grid technology, such as the development of a charging infrastructure for electric cars.

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