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  • 1167851.
    Zhang, Yafan
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Nee, Hans Peter
    KTH Royal Institute of Technology, Sweden.
    Hammam, Tag
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Belov, Ilja
    Jönköping University, Sweden.
    Ranstad, Per
    GE Power Sweden AB, Sweden.
    Bakowski, Mietek
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Multiphysics Characterization of a Novel SiC Power Module2019In: IEEE Transactions on Components, Packaging, and Manufacturing Technology, ISSN 2156-3950, E-ISSN 2156-3985, Vol. 9, no 3, p. 489-501Article in journal (Refereed)
    Abstract [en]

    This paper proposes a novel power module concept specially designed for highly reliable silicon carbide power devices for medium- and high-power applications. The concept consists of two clamped structures: 1) a press-pack power stage accommodating silicon carbide power switch dies, and 2) perpendicularly clamped press-pack heatsinks, in which, the heatsinks are in contact with electrically insulated case plates of the power stage. The concept enables bondless package with symmetric double-sided cooling of the dies and allows for an order of magnitude higher clamping force on the heatsinks than what can be applied on the dies. The concept has been evaluated in a first demonstrator (half-bridge configuration with ten paralleled silicon carbide dies in each position). Experimental methodologies, setups, and procedures have been presented. The commutation loop inductance is approximately 9 nH at 78 kHz. The junction-to-case thermal resistance is approximately 0.028 K/W. Furthermore, a simplified 3D finite element thermomechanical model representing the center unit of the demonstrator, has been established for the purpose of future optimization. The accuracy of the simulated temperatures is within 4 % compared to the measurements. Finally, a 3D thermomechanical stress distribution map has been obtained for the simplified model of the demonstrator.

  • 1167852.
    Zhang, Yafan
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Electric Power and Energy Systems. Department of Netlab, RISE Acreo AB, Kista, Sweden.
    Nee, Hans-Peter
    KTH, School of Electrical Engineering and Computer Science (EECS), Electric Power and Energy Systems.
    Hammam, Tag
    Belov, Ilja
    Ranstad, Per
    Bakowski, Mietek
    Multiphysics Characterization of a Novel SiC Power Module2019In: IEEE transactions on components, packaging, and manufacturing technology. Part A (Print), ISSN 1070-9886, E-ISSN 1558-3678, Vol. 9, no 3, p. 489-501Article in journal (Refereed)
    Abstract [en]

    This paper proposes a novel power module concept specially designed for highly reliable silicon carbide (SiC) power devices for medium- and high-power applications. The concept consists of two clamped structures: 1) a press-pack power stage accommodating SiC power switch dies and 2) perpendicularly clamped press-pack heatsinks, in which the heatsinks are in contact with electrically insulated case plates of the power stage. The concept enables bondless package with symmetric double-sided cooling of the dies and allows for an order of magnitude higher clamping force on the heatsinks than what can be applied on the dies. The concept has been evaluated in a first demonstrator (half-bridge configuration with 10 paralleled SiC dies in each position). The experimental methodologies, setups, and procedures have been presented. The commutation loop inductance is approximately 9 nH at 78 kHz. The junction-to-case thermal resistance is approximately 0.028 K/W. Furthermore, a simplified 3-D finite-element thermomechanical model representing the center unit of the demonstrator has been established for the purpose of future optimization. The accuracy of the simulated temperatures is within 4% compared to the measurements. Finally, a 3-D thermomechanical stress distribution map has been obtained for the simplified model of the demonstrator.

  • 1167853.
    Zhang, Yafan
    et al.
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems. RISE Acreo AB, Sweden.
    Neumaier, K.
    Zschieschang, O.
    Weis, G.
    Schmid, G.
    Bakowski, M.
    Nee, Hans-Peter
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems.
    Simulation-driven development of a novel SiC embedded power module design concept2017In: 2017 18th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems, EuroSimE 2017, Institute of Electrical and Electronics Engineers (IEEE), 2017, article id 7926252Conference paper (Refereed)
    Abstract [en]

    Silicon carbide embedded power modules enable a compact and cost competitive packaging solution for high-switching frequency and high-temperature operation applications. Power module packaging technologies span several engineering domains. At the early design stage, simulation-driven development is necessary to shorten the design period and reduce the design cost. This paper presents a novel design concept of a three-phase embedded power module (1200 V, 20 A, 55 mm × 36 mm × 0.808 mm) including silicon carbide metal-oxide-semiconductor field-effect transistor and antiparallel diode dies. Based on the E/CAD design data different layer built-up designs have been tested against thermal, mechanical, and electrical behavior. The obtained simulation data then have been evaluated against a commercial available power module (Motion Smart Power Module SMP33) which utilizes over mold direct bonded copper substrates with soldered semiconductor dies and bond wire contacts. Compared to the conventional module, the loop conductive interconnection parasitic inductance and resistance of the design concept (Vdc+ to Vdc-) reduces approximately by 88 % and 72 %, respectively. The average junction to case thermal resistance has been improved by approximately more than 10 % even though the total package size reduces by approximately 88 %. Furthermore, the contours of deformation and stresses have been investigated for the design concept in the thermomechanical simulation.

  • 1167854.
    Zhang, Yafan
    et al.
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Neumaier, Klaus
    ON Semiconductor Gmhb, Germany; Fairchild Semiconductor Gmhb, Germany.
    Zschieschang, Olaf
    ON Semiconductor Gmhb, Germany; Fairchild Semiconductor Gmhb, Germany.
    Weis, Gerald
    AT & S Austria Technologie & Systemtechnik, Austria.
    Schmid, Gerhard
    AT & S Austria Technologie & Systemtechnik, Austria.
    Bakowski, Mietek
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Nee, Hans Peter
    KTH Royal Institute of Technology, Sweden.
    Simulation-driven development of a novel SiC embedded power module design concept2017In: 2017 18th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems, EuroSimE 2017, 2017Conference paper (Refereed)
    Abstract [en]

    Silicon carbide embedded power modules enable a compact and cost competitive packaging solution for high-switching frequency and high-temperature operation applications. Power module packaging technologies span several engineering domains. At the early design stage, simulation-driven development is necessary to shorten the design period and reduce the design cost. This paper presents a novel design concept of a three-phase embedded power module (1200 V, 20 A, 55 mm × 36 mm × 0.808 mm) including silicon carbide metal-oxide-semiconductor field-effect transistor and antiparallel diode dies. Based on the E/CAD design data different layer built-up designs have been tested against thermal, mechanical, and electrical behavior. The obtained simulation data then have been evaluated against a commercial available power module (Motion Smart Power Module SMP33) which utilizes over mold direct bonded copper substrates with soldered semiconductor dies and bond wire contacts. Compared to the conventional module, the loop conductive interconnection parasitic inductance and resistance of the design concept (Vdc+ to Vdc-) reduces approximately by 88 % and 72 %, respectively. The average junction to case thermal resistance has been improved by approximately more than 10 % even though the total package size reduces by approximately 88 %. Furthermore, the contours of deformation and stresses have been investigated for the design concept in the thermomechanical simulation.

  • 1167855.
    Zhang, Yalan
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Discussion on how to motive and retain employees in China by exploring the factors influencing employee enthusiasm at work -- applying two-factory theory in P&G employees2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This research discusses how to motive and retain employees in China based on analyzing factors influencing employee enthusiasm and strategies to motivate employees under the framework of Herzberg’s two-factor theory. With the proposition that hygiene factors and motivators both influence the work enthusiasm, 15 interviews were arranged to collect the needed data for further analysis. According to the information obtained from the 15 interviewees from P&G, hygiene factors and motivators all exert influences over their work behaviors and the impact of the factors differs according to the different conditions of the employees. The findings of this research generally agree with the two-factor theory. Based on how the work enthusiasm of P&G’s employees are influenced by each of the factors, strategies are correspondingly formulated to motivate employees at work. Generally speaking, this research is significant for being conducted from a microscopic perspective to the macroscopic perspective. In other words, a specific organization is studied to figure out the answers to the research questions and the findings can be used for future studies as well for practical purposes.

    More specifically, when conducting this study, such factors as unsatisfying wages and benefits, heavy workload, task conflicts, ambiguous duties, interpersonal conflicts and ineffective management system, etc., all discourage the enthusiasm of employees. In response to that, a reasonable management system and sound motivational mechanism should be established to keep employees active at work or retain those who want to resign.

  • 1167856.
    Zhang, Yan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Chemoenzymatic Resolution in Dynamic Systems: Screening, Classification and Asymmetric Synthesis2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This  thesis  is  divided  into  four  parts,  all  centered  around  Constitutional Dynamic  Chemistry  (CDC)  and  Dynamic  Kinetic  Resolution  (DKR)  using biocatalysts for selective transformations, and their applications in screening of bioactive compounds, organic synthesis, and enzyme classification.   

    In  part  one,  an  introduction  to  CDC  and  DKR  is  presented,  illustrating  the basic  concepts,  practical  considerations  and  potential  applications  of  such dynamic systems, thus providing the background information for the studies in the following chapters.  

    In part two, Dynamic Systemic Resolution (DSR), a concept based on CDC is exemplified.  With  enzyme-catalyzed  transformations  as  external  selection pressure,  optimal  structures  can  be  selected  and  amplified  from  the  system. This  concept  is  expanded  to  various  types  of  dynamic  systems  containing single, double cascade/parallel, and multiple reversible reactions. In addition, the  substrate  selectivity  and  catalytic  promiscuity  of  target  enzymes  are  also investigated.  

    In   part   three,   DKR   protocols   using   reversible   reactions   for   substrate racemizations  are  illustrated.  Biocatalysts  are  here  employed  for  asymmetric transformations,  resulting  in  efficient  synthetic  pathways  for  enantioenriched organic compounds.  

    Part  four  demonstrates  two  unique  applications  of  CDC:  one  resulting  in enzyme  classification  by  use  of  pattern  recognition  methodology;  the  other involving  enzyme  self-inhibition  through  in  situ  transformation  of  stealth inhibitors employing the catalytic activity of the target enzyme.

  • 1167857.
    Zhang, Yan
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Patch Antenna for 1420MHz Radio Telescope2007Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Patch antenna is one of the most rapidly popular topics in the antenna field in the past twenty years. In high-performance aircraft, spacecraft, satellite and missile applications, where size, weight, cost, performance, ease of installation, and aerodynamic profile are constraints, low profile antennas may be required. [7].

    The project is to develop a single patch antenna operating on a specific frequency 1420MHz. The frequencies near to 1420MHz are worth to observe because the hydrogen in throughout of the space can be mapped by the observation of the 21 – cm wavelength line which is corresponding to 1420 MHz radiation. The final product antenna will be used in a radio telescope as a part of the signal receiving system.

    The work within the project contains simulation, fabrication and test of final antenna. The simulation work was carried out in advanced design system which is developed by Agilent technologies, USA. The most different feature of the project is that, comparing to normal patch antenna, usually 50 ohms is selected as the matching impedance, while in this project we made it conjugate to the input impedance of the LNA. In this way we can save extra components, as well as energy consuming.

  • 1167858.
    Zhang, Yan
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Wireless sensor network for volcano monitoring2005Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The monitoring of volcanoes for risk assessment has deployed single sensors for years. This kind of system requires manual supervision to monitor each sensor, which makes the monitoring work not flexible and efficient enough to adapt to variable volcano environments. With the development of wireless sensor networks, the accuracy and coverage of volcano observations can be improved by deploying networked sensors. This paper proposes a wireless sensor network prototype for volcano remote monitoring, which was built and tested in a field campaign in volcano Etna, Italy in September of 2004.Hardware design of sensors, in-depth sensor network design and software module architecture will be introduced in this paper. The experience gained from the practical work in volcano Etna will be used in an upcoming volcano monitoring project.

  • 1167859.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Angelin, Marcus
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Larsson, Rikard
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Albers, Antonia
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Simons, Adrian
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Tandem driven dynamic self-inhibition of acetylcholinesterase2010In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 46, no 44, p. 8457-8459Article in journal (Refereed)
    Abstract [en]

    A concept of tandem driven dynamic self-inhibition is demonstrated through dynamic inhibitors of acetylcholinesterase (AChE) using reversible transthiolesterification.

  • 1167860.
    Zhang, Yan
    et al.
    Blekinge Institute of Technology, School of Engineering.
    Chen, Xi
    Blekinge Institute of Technology, School of Engineering.
    Value-Driven Needfinding for Early Product: Service System Development. A Study Collaborates with Volvo Construction Equipments in Chinese Market2012Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Many literatures have shown that needs last longer than any specific solutions, so understanding of customer needs seems a crucial factor in early Product-Service System (PSS) development. Nowadays, many western companies, especially manufacturing focused companies, have realized the difficulty of understanding market needs. In this thesis, a new Value-Driven Needfinding methodology for manufacturing company to apply in certain markets was investigated. To further demonstrate the implementation of the proposed methodology, a case study involving Volvo Construction Equipment exploring value-orient needs in Chinese market is showed. At the end, by providing the scenarios comparison, a PSS conceptual design will be illustrated to show the utilization of the customer needs, then opportunities for company future provision towards sustainability based on early PSS development will be discussed.

  • 1167861.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Hu, Lei
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Double parallel dynamic resolution through lipase-catalyzed asymmetric transformation2013In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 49, no 18, p. 1805-1807Article in journal (Refereed)
    Abstract [en]

    Dynamic systems based on double parallel reactions have been generated and resolved in situ by secondary lipase-catalyzed asymmetric transformation, resulting in high chemo- and enantioselectivities.

  • 1167862.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Jayawardena, H. Surangi N.
    Yan, Mingdi
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. University of Massachusetts Lowell, MA, United States.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Enzyme classification using complex dynamic hemithioacetal systems2016In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 52, no 28, p. 5053-5056Article in journal (Refereed)
    Abstract [en]

    A complex dynamic hemithioacetal system was generated for the evaluation of lipase reactivities in organic media. In combination with pattern recognition methodology, twelve different lipases were successfully classified into four distinct groups following their reaction selectivities and reactivities. A probe lipase was further categorized using the training matrix with predicted reactivity.

  • 1167863.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Jayawardena, Surangi
    Yan, Mingdi
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Classification of Lipases Using Pattern Recognition through Transformation of Dynamic Hemithioacetal SystemsArticle in journal (Other academic)
    Abstract [en]

    A complex dynamic hemithioacetal system was generated for the evaluation of lipase reactivities. In combination with pattern recognition methodology, twelve different lipases were successfully classified into three distinct groups following their reaction selectivities and reactivities. A probe lipase was further categorized using the training matrix with predicted reactivity.

  • 1167864.
    Zhang, Yan
    et al.
    Department of Informatics, University of Oslo, Oslo, Norway.
    Jonsson, Magnus
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Li, Minqiang
    Department of Information Management and Management Science, Tianjin University, Tianjin, China.
    Guest editorial special issue on industrial IoT systems and applications2017In: IEEE Systems Journal, ISSN 1932-8184, E-ISSN 1937-9234, Vol. 11, no 3, p. 1337-1339, article id 8052330Article in journal (Other academic)
  • 1167865.
    Zhang, Yan
    et al.
    School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore, Singapore.
    Jonsson, MagnusHalmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).Li, MinqiangDepartment of Information Management and Management Science, College of Management and Economics, Tianjin University, Tianjin Shi, China.
    Special Issue on Industrial IoT Systems and Applications2017Collection (editor) (Refereed)
  • 1167866.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Lipase-Catalyzed Dynamic Systemic Resolution from Reversible Reaction NetworksArticle in journal (Other academic)
    Abstract [en]

    A dynamic system based on a network of multiple reversible reactions has been established. The network was applied to a dynamic systemic resolution protocol based on two kinetically controlled lipase-catalyzed transformations, where two compounds were efficiently selected from a pool of potential products.

  • 1167867.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Thiazolidinones Derived from Dynamic Systemic Resolution of Complex Reversible-Reaction Networks2014In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 20, no 12, p. 3288-3291Article in journal (Refereed)
    Abstract [en]

    A complex dynamic system based on a network of multiple reversible reactions has been established. The network was applied to a dynamic systemic resolution protocol based on kinetically controlled lipase-catalyzed transformations. This resulted in the formation of cyclized products, where two thiazolidinone compounds were efficiently produced from a range of potential transformations.

  • 1167868. Zhang, Yan
    et al.
    Sakulsombat, Morakot
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Vongvilai, Pornrapee
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Hu, Lei
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Lipase-mediated dynamic systemic resolution based on single or double reversible reactions2012In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 244Article in journal (Other academic)
  • 1167869.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Schaufelberger, Fredrik
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Sakulsombat, Morakot
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Liu, Chelsea
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Asymmetric Dynamic Kinetic Resolution for the Synthesis of 1,3-Oxathiolan-5-one DerivativesArticle in journal (Other academic)
    Abstract [en]

    Synthesis of 1,3-oxathiolan-5-one derivatives through dynamic kinetic resolution strategy has been illustrated, resulting in moderate to good enantioselectivities of the final products. In addition, the substrate scope and potential access to lamivudine (3TC) have also been explored.

  • 1167870.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Schaufelberger, Fredrik
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Sakulsombat, Morakot
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Liu, Chelsea
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Asymmetric synthesis of 1,3-oxathiolan-5-one derivatives through dynamic covalent kinetic resolution2014In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 70, no 24, p. 3826-3831Article in journal (Refereed)
    Abstract [en]

    The asymmetric synthesis of 1,3-oxathiolan-5-one derivatives through an enzyme-catalyzed, dynamic covalent kinetic resolution strategy is presented. Dynamic hemithioacetal formation combined with intramolecular, lipase-catalyzed lactonization resulted in good conversions with moderate to good enantiomeric excess (ee) for the final products. The process was evaluated for different lipase preparations, solvents, bases, and reaction temperatures, where lipase B from Candida antarctica (CAL-B) proved most efficient. The substrate scope was furthermore explored for a range of aldehyde structures, together with the potential access to nucleoside analog inhibitor core structures.

  • 1167871.
    Zhang, Yan
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Ulvmar, Maria H.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Stanczuk, Lukas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Martinez-Corral, Ines
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Frye, Maike
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Alitalo, Kari
    Wihuri Research Institute and Translational Cancer Biology Program, Biomedicum Helsinki, University of Helsinki, FIN-00014, Helsinki, Finland.
    Mäkinen, Taija
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Heterogeneity in VEGFR3 levels drives lymphatic vessel hyperplasia through cell-autonomous and non-cell-autonomous mechanisms2018In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 9, no 1, article id 1296Article in journal (Refereed)
    Abstract [en]

    Incomplete delivery to the target cells is an obstacle for successful gene therapy approaches. Here we show unexpected effects of incomplete targeting, by demonstrating how heterogeneous inhibition of a growth promoting signaling pathway promotes tissue hyperplasia. We studied the function of the lymphangiogenic VEGFR3 receptor during embryonic and post-natal development. Inducible genetic deletion of Vegfr3 in lymphatic endothelial cells (LECs) leads to selection of non-targeted VEGFR3+cells at vessel tips, indicating an indispensable cell-autonomous function in migrating tip cells. Although Vegfr3 deletion results in lymphatic hypoplasia in mouse embryos, incomplete deletion during post-natal development instead causes excessive lymphangiogenesis. Analysis of mosaically targeted endothelium shows that VEGFR3-LECs non-cell-autonomously drive abnormal vessel anastomosis and hyperplasia by inducing proliferation of non-targeted VEGFR3+LECs through cell-contact-dependent reduction of Notch signaling. Heterogeneity in VEGFR3 levels thus drives vessel hyperplasia, which has implications for the understanding of mechanisms of developmental and pathological tissue growth.

  • 1167872.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Vongvilai, Pornrapee
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Sakulsombat, Morakot
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Fischer, Andreas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Asymmetric Synthesis of Substituted Thiolanes through Domino Thia-Michael-Henry Dynamic Covalent Systemic Resolution using Lipase Catalysis2014In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 356, no 5, p. 987-992Article in journal (Refereed)
    Abstract [en]

    Dynamic systems based on consecutive thia-Michael and Henry reactions were generated and transformed using lipase-catalyzed asymmetric transformation. Substituted thiolane structures with three contiguous stereocenters were resolved in the process in high yields and high enantiomeric excesses.

  • 1167873.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Vongvilai, Pornrapee
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Sakulsombat, Morakot
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Fischer, Andreas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Biocatalyzed Dynamic Systemic Domino Thia-Michael--Henry Resolution to Substituted Asymmetric ThiolanesArticle in journal (Other academic)
    Abstract [en]

    Dynamic systems based on consecutive thia-Michael and Henry reactions were generated and transformed using lipase-catalyzed asymmetric transformation. Substituted thiolane structures with three contiguous stereocenters were resolved in the process in high yields and high enantiomeric excesses.

  • 1167874.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Zhang, Yang
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Asymmetric synthesis of oxazolidin-2-one derivatives through lipase-catalyzed kinetic resolution2014In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247Article in journal (Other academic)
  • 1167875.
    Zhang, Yan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Zhang, Yang
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ren, Yansong
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Synthesis of chiral oxazolidinone derivatives through lipase-catalyzed kinetic resolution2015In: Journal of Molecular Catalysis B: Enzymatic, ISSN 1381-1177, E-ISSN 1873-3158, Vol. 122, p. 29-34Article in journal (Refereed)
    Abstract [en]

    The synthesis of enantioenriched oxazolidinone derivatives through lipase-catalyzed kinetic resolution is described. The synthesis comprised a two-step, cascade acylation in one pot, resulting in a range of oxazolidinone derivatives in good yields and excellent enantiopurities.

  • 1167876.
    Zhang, Yang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    A visualization interface for spatial pathway regulation data2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Data visualization is an essential methodology for bioinformatics studies. Spatial Transcriptomics(ST) is a method that aims at measuring the transcriptome of tissue sections while maintaining its spacial information. Finally, the study of biological pathway focuses on a series of biochemical reactions that take place in organisms. As these studies generate a large number of datasets, this thesis attempts to combine the ST’s data with pathwayinformation and visualize it in an intuitive way to assist user comprehension and insight.In this thesis, Python was used for integrating the dataset and JavaScript libraries wereused for building the visualization. The processing of ST pathway data together with the data visualization interface are the outcomes of this thesis. The data visualization can show the regulation of pathways in the ST data and can be accessed by modern browsers. These outcomes can help users navigate the ST and pathway datasets more effectively.

  • 1167877.
    Zhang, Yang
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Dynamic Systems: Enzymatic Synthesis, Exchange Reactions and Applications in Materials Science2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis is divided into three parts, revolving around the developments of dynamic systems utilized in dynamic kinetic resolution (DKR) and constitutional dynamic chemistry (CDC).

    The first section gives an introduction to constitutional dynamics, the core concept of this thesis. Constitutional dynamics can be tuned through reversible interactions. Then, the basic principles of constitutional dynamics in DKR and CDC are discussed, along with their applications.

    The second section explores the asymmetric synthesis of oxazolidinone derivatives using lipase catalysis through kinetic resolution (KR) and dynamic kinetic resolution. In the first example, synthetic protocol to enantioenriched 5-phenyloxazolidin-2-ones is described, where a kinetically controlled carbamation is followed by lipase-catalyzed cyclization. In contrast to the 5-substituted species, the synthesis of 3-phenyloxazolidin-2-one derivatives could be achieved through lipase-catalyzed cascade O- and N- alkoxycarbonylations in one pot. Furthermore, this KR system could be coupled to a ruthenium-catalyzed racemization process of 1,2-aminoalcohols, thus providing an efficient DKR methodology for asymmetric transformations.

    The third section focuses on dynamic systems built through reversible covalent reactions. In the first example, a selective gelation process is described, and employed to resolve dynamic imine systems consisting of gelator candidates.  In the second example, reversible reactions with aldehyde enamines are presented, including enamine formation and exchange reactions. In particular, Bi(III) and Sc(III) were discovered to accelerate the enamine exchange reactions by 50-400 times, in which the equilibria could be reached within hours. The last example describes reversible nitroaldol reactions in aqueous media, where rapid and efficient equilibration was identified for selected structures in neutral phosphate buffer.

  • 1167878.
    Zhang, Yang
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Integration of Battery and Hydrogen Storage with a Grid-Connected Photovoltaic System in Buildings2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

        The integration of Photovoltaic (PV) with buildings changes the previous electricity consumers into prosumers. The reduced PV subsidies and the grid stable operation requirements are pushing prosumers from direct exportation to self-consumption of the produced electricity. Electricity storage increases the self-consumption, while comes with higher investment. During the system planning stage, the benefits of storage should be clarified to prosumers. The storage type, the storage capacity and the system operation strategy should be determined at the same time.

        This thesis dealt with a grid-connected PV-storage system and proposed an optimization method, which simultaneously determined the storage capacity and rule-based operation strategy parameters. This method eliminated the necessity of forecasting and could be easily implemented. A typical residential building in Sweden was taken as a case study. Different operation strategies as well as two storage technologies – battery storage and hydrogen storage – were compared.

        For the battery storage system, the proposed battery hybrid operation strategy, which carries out the conventional operation strategy during warm months and the peak shaving strategy during cold months, provides the best performance in Self Sufficiency Ratio (SSR) and Net Present Value (NPV). For the hydrogen storage system, the hydrogen hybrid operation strategy outperforms other studied operation strategies under different scenarios, which have optimistic or pessimistic cost assumptions of the hydrogen storage system.

        The comparison between hydrogen storage and battery storage suggests that battery storage has much better performance in SSR and NPV under the pessimistic cost scenario. Under the optimistic cost scenario, battery storage and hydrogen storage achieve comparable performance in SSR and NPV. However, hydrogen storage is more favorable when considering reducing the prosumer’s negative impact on the grid.

  • 1167879.
    Zhang, Yang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Integration of Distributed Renewable Energy and Energy Storages in Buildings2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Photovoltaic (PV) is a distributed renewable energy technology that is suitable for integration in buildings. PV reduces the electricity demands as well as the greenhouse gas emissions of buildings. However, the surplus electricity from PV is exported to the electricity grid, which not only lowers the economic performance of the PV but also creates operational problems in the grid. Efficient approaches should be identified to improve PV’s economic and environmental performance.

    Buildings differ by their connections to energy networks. In buildings that are only connected to the electricity grid, electrical energy storages— including battery and hydrogen storage—can mitigate the mismatch between production and consumption. When a grid-connected PV system follows the conventional operation strategy, its economic performance worsens with storage. Two new operation strategies are developed. With a developed optimization framework, operation strategies and storage capacities are optimized simultaneously. Optimization results indicate that both net present value and self-sufficiency ratio are increased by storages. A comparison between battery storages and hydrogen storages shows that the hydrogen storage can compete with the battery counterpart under an optimistic hydrogen storage cost scenario. In addition, the hydrogen storage can better decrease the exported electricity.

    In buildings that are connected to the electricity grid and the district heating network, additional energy conversion and storage equipment— including heat pumps, electrical heaters, and hot water tanks—can be installed to form an integrated energy system (IES). After optimal system sizing, the IES decreases the net present cost by 22%, and the self-consumption ratio increases from 43% to 61%. Moreover, the IES serves as a new flexibility measure, and the provided flexibility energy is over 36% of its electricity consumption. During system planning, the system configuration and operation cost are obtained without considering forecast errors. Through the year-round simulation of system operation that considers forecast errors, a corrected operation cost is obtained. The yearly operation cost difference between system operation and system planning is less than 4% and 6% under the high and low forecast accuracy scenarios.

    The full text will be freely available from 2019-12-31 12:46
  • 1167880.
    Zhang, Yang
    Mälardalen University, School of Innovation, Design and Engineering.
    Kanban Re-engineers Production Process In Åkers Sweden AB2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Kanban, as well known as a practical toolkit of Lean, has become popular over recent years. Many companies are using Kanban to change and improve their own business and production situations. And many Kanban teams have reported successful implementations. However, there is no single best way to implement Kanban. What each Kanban entity does is to experiment.Kanban has been introduced to Åkers Sweden AB since the second half of 2008, when the global economic risk stated sweeping the world. Facing the shrunk demand, Kanban did drag Åkers Sweden out of the recession swamp. At present, Åkers Sweden is still on the implementing process of its updated Kanban philosophy. There are many obstacles need to overcome, a lot of vagueness need to be clarified, a crowd of aspects need to be improved.Facing this dynamic implementing condition, this thesis is expected to yield in a more practical oriented way, in order to deal with the existing problem in Åkers Sweden.In this thesis, description is used as an essential method to reveal different aspects of Kanban and illustrate how Kanban works. The Kanban is described from both partly and holistic ways. It is decomposed into several components, which is described respectively. And the holistic Kanban is mainly reflected on its goal.This detailed description does a preparation for the evaluation and analysis. SWOT analysis is used as the main analysis tool. Since the analysis process is very open, any thoughtful thinking could be involved into the outcomes. And the main purpose of the Kanban analysis is to inspire more re-thinking and realize continuous improvement.

  • 1167881.
    Zhang, Yang
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Organ-specific mechanisms of vascular development in the mesentery2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Understanding how the vascular systems are formed has significant clinical importance. General mechanisms underlying vascular development have been extensively studied during the past decades. However, the mechanisms regulating the development and function of the blood and lymphatic vessels in specific organs are poorly understood.

    The aim of this thesis was to investigate lymphatic vascular development in the mesentery, which is a fold of peritoneum that attaches the intestine to the abdominal wall, and contains arteries, veins, lymphatic vessels, nerves and lymph nodes. We found that mesenteric lymphatic vessels were formed through lymphvasculogenesis - coalescence of isolated lymphatic endothelial cell (LEC) clusters, rather than by lymphangiogenesis - sprouting from the veins or pre-existing lymphatic vessels. The lymphvasculogenic process was selectively sensitive to inhibition of the vascular endothelial growth factor receptor 3 (VEGFR3)/ phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) signaling pathway. Using genetic lineage tracing, we uncovered that part of the mesenteric lymphatic vasculature was derived from cKit lineage cells likely originating from the blood-forming hemogenic endothelium of major arteries (Paper I). This is in contrast to the previously accepted dogma that all mammalian lymphatic vessels are of venous endothelial origin. By characterizing a mouse mutant lacking the non-venous-derived LEC progenitors we found that an alternative venous source of LECs could however compensate to build a functional mesenteric lymphatic vasculature (Paper IV). We further described in the developing mesentery that a transient loss of venous integrity, characterized by the formation of inter-endothelial cell gaps, was accompanied by extravasation of red blood cells, which were cleared by the developing lymphatic vessels. By studying mice with defective platelet function, we revealed a previously unappreciated role of platelets in maintaining the integrity of the remodeling embryonic blood vasculature and thus preventing excessive blood-filling of lymphatic vessels (Paper III). We also studied the mechanism of vessel maturation into functional lymphatic vessels, which involves smooth muscle cell recruitment. Analysis of mice with LEC-specific deletion of Pdgfb, encoding the platelet derived growth factor B (PDGFB), showed that LEC-autonomous PDGFB was required for the recruitment of smooth muscles cells that in turn control lymphatic vessel size and function (Paper II).

  • 1167882.
    Zhang, Yang
    et al.
    Resilience Engineering Research Group, University of Nottingham.
    Andrews, John
    Resilience Engineering Research Group, University of Nottingham.
    Reed, Sean
    Resilience Engineering Research Group, University of Nottingham.
    Karlberg, Magnus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Product and Production Development.
    Maintenance Processes Modelling and Optimisation2017In: Reliability Engineering & System Safety, ISSN 0951-8320, E-ISSN 1879-0836, Vol. 168, p. 150-160Article in journal (Refereed)
    Abstract [en]

    A Maintenance Procedure is conducted in order to prevent the failure of a system or to restore the functionality of a failed system. Such a procedure consists of a series of tasks, each of which has a distribution of times to complete and a probability of being performed incorrectly. The inclusion of tests can be used to identify any maintenance errors which have occurred. When an error is identified it can be addressed through a corresponding correction sequence which will have associated costs and add to the maintenance process completion time. A modified FMEA approach has been used to identify the possible tests. By incorporating any selection of tests into the maintenance process it can then analysed using a discrete-event simulation to predict the expected completion time distribution. The choice of tests to perform and when to do them is then made to successfully complete the maintenance objective in the shortest possible time using a genetic algorithm. The methodology is demonstrated by applying it to the repair process for a car braking system. The developed method is suitable for application in abroad range of industries.

  • 1167883.
    Zhang, Yang
    et al.
    KTH Royal Institute of Technology, Sweden.
    Campana, Pietro E.
    KTH Royal Institute of Technology, Sweden; Mälardalen University, Sweden.
    Yang, Ying
    Mälardalen University, Sweden.
    Stridh, Bengt
    Mälardalen University, Sweden.
    Lundblad, Anders Olof
    RISE - Research Institutes of Sweden, Safety and Transport, Electronics.
    Yan, Jinyue
    KTH Royal Institute of Technology, Sweden; Mälardalen University, Sweden.
    Energy flexibility from the consumer: Integrating local electricity and heat supplies in a building2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 223, p. 430-442Article in journal (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energy requires more flexibility measures to be implemented in future energy systems. Integrating an energy consumer's local energy supplies connects multiple energy networks (i.e., the electrical grid, the district heating network, and gas network) in a decentralized way. Such integration enhances the flexibility of energy systems. In this work, a Swedish office building is investigated as a case study. Different components, including heat pump, electrical heater, battery and hot water storage tank are integrated into the electricity and heat supply system of the building. Special focus is placed on the flexibility that the studied building can provide to the electrical grid (i.e., the building modulates the electricity consumption in response to the grid operator's requirements). The flexibility is described by two metrics including the flexibility hours and the flexibility energy. Optimization of the component capacities and the operation profiles is carried out by using Mixed Integer Linear Programming (MILP). The results show that the system fully relies on electricity for the heat demand when not considering the flexibility requirements of the electrical grid. This suggests that district heating is economically unfavorable compared with using electricity for the heat demand in the studied case. However, when flexibility requirements are added, the system turns to the district heating network for part of the heat demand. The system provides great flexibility to the electrical grid through such integration. The flexibility hours can be over 5200 h in a year, and the flexibility energy reaches more than 15.7 MWh (36% of the yearly electricity consumption). The yearly operation cost of the system slightly increases from 62,273 to 65,178 SEK when the flexibility hours increase from 304 to 5209 h. The results revealed that flexibility can be provided from the district heating network to the electrical grid via the building.

  • 1167884.
    Zhang, Yang
    et al.
    KTH Royal Inst Technol, Sweden.
    Campana, Pietro Elia
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Anders, Lundblad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH Royal Inst Technol, Sweden.
    Comparative study of hydrogen storage and battery storage in grid connected photovoltaic system: Storage sizing and rule-based operation2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 201, p. 397-411Article in journal (Refereed)
    Abstract [en]

    The paper studies grid-connected photovoltaic (PV)-hydrogen/battery systems. The storage component capacities and the rule-based operation strategy parameters are simultaneously optimized by the Genetic Algorithm. Three operation strategies for the hydrogen storage, namely conventional operation strategy, peak shaving strategy and hybrid operation strategy, are compared under two scenarios based on the pessimistic and optimistic costs. The results indicate that the hybrid operation strategy, which combines the conventional operation strategy and the peak shaving strategy, is advantageous in achieving higher Net Present Value (NPV) and Self Sufficiency Ratio (SSR). Hydrogen storage is further compared with battery storage. Under the pessimistic cost scenario, hydrogen storage results in poorer performance in both SSR and NPV. While under the optimistic cost scenario, hydrogen storage achieves higher NPV. Moreover, when taking into account the grid power fluctuation, hydrogen storage achieves better performance in all three optimization objectives, which are NPV, SSR and GI (Grid Indicator). 

  • 1167885. Zhang, Yang
    et al.
    Campana, Pietro Elia
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Anders, Lundblad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Zhang, Chi
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Sweden.
    Building Energy System: From System Planning To Operation2018Conference paper (Refereed)
  • 1167886.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Lundblad, Anders
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Wandong, Zheng
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Planning and Operation of an Integrated Energy System in a Swedish BuildingManuscript (preprint) (Other academic)
    Abstract [en]

    The increasing capacities of variable renewable energies (VRE) require more flexibility measures. The integration of energy supplies in buildings forms integrated energy systems (IES). IESs can provide flexibility and help increase the VRE penetration level. To upgrade a current building energy system into an IES, several energy conversion and storage components need to be installed. How to decide the component capacities and operate the IES were investigated separately in studies on system planning and system operation. However, a research gap exists that the system configuration from system planning is not validated by real operation conditions in system operation. Meanwhile, studies on system operation assume that the IES configuration is predetermined. This work combines system planning and system operation. The IES configuration is determined by mixed integer linear programming in system planning. Real operation conditions and forecast errors are considered in the system operation. The operation profiles are obtained through different energy management systems. The results indicate that the system configuration from system planning can meet energy demands in real operation conditions. Among different energy management systems, the combination of robust optimization and receding horizon optimization achieves the lowest yearly operation cost. Meanwhile, two scenarios that represent high and low forecast accuracies are employed. Under the high and low forecast accuracy scenarios, the yearly operation costs are about 4% and 6% higher than those obtained from system planning.

  • 1167887.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Campana, Pietro Elia
    Lundblad, Anders
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Wang, Lei
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    The Influence of Photovoltaic Models and Battery Models in System Simulation and Optimization2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105C, p. 1185-1192Article in journal (Refereed)
    Abstract [en]

    Selecting accurate and robust models is important for simulation and optimization of a clean energysystem. This paper compares two photovoltaic (PV) models and two battery models in an open-sourcecode, Opti-CE. The PV models are single diode model and its simplified model. The battery models areImproved Shepherd model and energy balance model. The models are compared from a perspective ofoverall system simulation and optimization in particular on both accuracy and computational time. Theresults indicate that simplified PV model causes 0.86% normalized root mean square error (nRMSE)compared with the single diode model, while decreases the simulation time from more than 800s to lessthan 0.01s. The energy balance battery model reduces simulation time from more than 5s to less than0.03s. The energy balance model tends to underestimate the battery State of Charge (SOC) compared withthe Improved Shepherd model. However, the error is not accumulative during the simulation. Comparedto the Pareto front with single diode model and Improved Shepherd model, the simplified PV modelincreases the Pareto front values and result in both higher Self Sufficiency Ratio (SSR) and Net PresentValue (NPV), while the energy balance battery model decreases the part of Pareto front, whereindividuals have low NPV.

  • 1167888.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Campana, Pietro Elia
    Lundblad, Anders
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Comparative study of hydrogen storage and battery storage in gridconnected photovoltaic system: Storage sizing and rule-basedoperation2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118Article in journal (Refereed)
    Abstract [en]

    The paper studies grid-connected photovoltaic (PV)-hydrogen/battery systems. The storage componentcapacities and the rule-based operation strategy parameters are simultaneously optimized by theGenetic Algorithm. Three operation strategies for the hydrogen storage, namely conventional operationstrategy, peak shaving strategy and hybrid operation strategy, are compared under two scenarios basedon the pessimistic and optimistic costs. The results indicate that the hybrid operation strategy, whichcombines the conventional operation strategy and the peak shaving strategy, is advantageous in achievinghigher Net Present Value (NPV) and Self Sufficiency Ratio (SSR). Hydrogen storage is further comparedwith battery storage. Under the pessimistic cost scenario, hydrogen storage results in poorer performancein both SSR and NPV. While under the optimistic cost scenario, hydrogen storage achieves higher NPV.Moreover, when taking into account the grid power fluctuation, hydrogen storage achieves better performancein all three optimization objectives, which are NPV, SSR and GI (Grid Indicator).

  • 1167889.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Yang, Ying
    Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Lundblad, Anders
    RISE Res Inst Sweden, Div Safety & Transport Elect, SE-50462 Borås, Sweden..
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Energy Flexibility through the Integrated Energy Supply System in Buildings: A Case Study in Sweden2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 564-569Conference paper (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energies requires more flexibility measures at the consumption side. Flexible energy prices have been placed by energy providers to promote flexibility measures from energy users. However, because of the current energy supply system in buildings, these flexible energy prices haven't been fully taken advantage of This study focuses on the integrated energy supply system in buildings. A Swedish office building is used as the case study. The integrated energy supply system is built by installing new components, including battery, heat pump and electrical heater, and hot water tank. Mixed Integer Linear Programming (MILP) problems are solved to determine the optimal component capacities and operation profiles. The results indicate that all the studied system configurations achieve lower net present cost (NPC) than the current system. It suggests that the integrated energy supply system can take advantage of the flexible energy prices and lower the overall energy cost in the building. Among the studied configurations, the combination of air source heat pump (ASHP) and electrical heater (EH) has the lowest investment cost. This combination also has the lowest NPC except in the scenario with low borehole cost.

  • 1167890.
    Zhang, Yang
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Campana, Pietro Elia
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yang, Ying
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lundblad, Anders
    Division Safety and Transport/Electronics, RISE Research Institutes of Sweden, SE-50462 Borås, Sweden.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Energy Flexibility through the Integrated Energy Supply System in Buildings: A Case Study in Sweden2018In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 145, p. 564-569Article in journal (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energies requires more flexibility measures at the consumption side. Flexible energy prices have been placed by energy providers to promote flexibility measures from energy users. However, because of the current energy supply system in buildings, these flexible energy prices haven’t been fully taken advantage of. This study focuses on the integrated energy supply system in buildings. A Swedish office building is used as the case study. The integrated energy supply system is built by installing new components, including battery, heat pump and electrical heater, and hot water tank. Mixed Integer Linear Programming (MILP) problems are solved to determine the optimal component capacities and operation profiles. The results indicate that all the studied system configurations achieve lower net present cost (NPC) than the current system. It suggests that the integrated energy supply system can take advantage of the flexible energy prices and lower the overall energy cost in the building. Among the studied configurations, the combination of air source heat pump (ASHP) and electrical heater (EH) has the lowest investment cost. This combination also has the lowest NPC except in the scenario with low borehole cost.

  • 1167891.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Västerås, Sweden.
    Yang, Ying
    Stridh, Bengt
    Lundblad, Anders
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Västerås, Sweden.
    Energy flexibility from the consumer: Integrating local electricity and heat supplies in a building2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 223, p. 430-442Article in journal (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energy requires more flexibility measures to be implemented in future energy systems. Integrating an energy consumer's local energy supplies connects multiple energy networks (i.e., the electrical grid, the district heating network, and gas network) in a decentralized way. Such integration enhances the flexibility of energy systems. In this work, a Swedish office building is investigated as a case study. Different components, including heat pump, electrical heater, battery and hot water storage tank are integrated into the electricity and heat supply system of the building. Special focus is placed on the flexibility that the studied building can provide to the electrical grid (i.e., the building modulates the electricity consumption in response to the grid operator's requirements). The flexibility is described by two metrics including the flexibility hours and the flexibility energy. Optimization of the component capacities and the operation profiles is carried out by using Mixed Integer Linear Programming (MILP). The results show that the system fully relies on electricity for the heat demand when not considering the flexibility requirements of the electrical grid. This suggests that district heating is economically unfavorable compared with using electricity for the heat demand in the studied case. However, when flexibility requirements are added, the system turns to the district heating network for part of the heat demand. The system provides great flexibility to the electrical grid through such integration. The flexibility hours can be over 5200 h in a year, and the flexibility energy reaches more than 15.7 MWh (36% of the yearly electricity consumption). The yearly operation cost of the system slightly increases from 62,273 to 65,178 SEK when the flexibility hours increase from 304 to 5209 h. The results revealed that flexibility can be provided from the district heating network to the electrical grid via the building.

  • 1167892.
    Zhang, Yang
    et al.
    KTH Royal Institute of Technology, Sweden.
    Campana, Pietro
    KTH Royal Institute of Technology, Sweden; Mälardalen University, Sweden.
    Yang, Ying
    Mälardalen University, Sweden.
    Lundblad, Anders Olof
    RISE - Research Institutes of Sweden, Safety and Transport, Electronics.
    Yan, Jinyue
    KTH Royal Institute of Technology, Sweden; Mälardalen University, Sweden.
    Energy Flexibility through the Integrated Energy Supply System in Buildings: A Case Study in Sweden2018In: Energy Procedia, 2018, p. 564-569Conference paper (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energies requires more flexibility measures at the consumption side. Flexible energy prices have been placed by energy providers to promote flexibility measures from energy users. However, because of the current energy supply system in buildings, these flexible energy prices haven't been fully taken advantage of. This study focuses on the integrated energy supply system in buildings. A Swedish office building is used as the case study. The integrated energy supply system is built by installing new components, including battery, heat pump and electrical heater, and hot water tank. Mixed Integer Linear Programming (MILP) problems are solved to determine the optimal component capacities and operation profiles. The results indicate that all the studied system configurations achieve lower net present cost (NPC) than the current system. It suggests that the integrated energy supply system can take advantage of the flexible energy prices and lower the overall energy cost in the building. Among the studied configurations, the combination of air source heat pump (ASHP) and electrical heater (EH) has the lowest investment cost. This combination also has the lowest NPC except in the scenario with low borehole cost. © 2018 The Authors. Published by Elsevier Ltd.

  • 1167893.
    Zhang, Yang
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Daubel, Nina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Stritt, Simon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Mäkinen, Taija
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Transient loss of venous integrity during developmental vascular remodeling leads to red blood cell extravasation and clearance by lymphatic vessels2018In: Development, ISSN 0950-1991, E-ISSN 1477-9129, Vol. 145, no 3, article id dev156745Article in journal (Refereed)
    Abstract [en]

    Maintenance of blood vessel integrity is crucial for vascular homeostasis and is mainly controlled at the level of endothelial cell (EC) junctions. Regulation of endothelial integrity has largely been investigated in the mature quiescent vasculature. Less is known about how integrity is maintained during vascular growth and remodeling involving extensive junctional reorganization. Here, we show that embryonic mesenteric blood vascular remodeling is associated with a transient loss of venous integrity and concomitant extravasation of red blood cells (RBCs), followed by their clearance by the developing lymphatic vessels. In wild-type mouse embryos, we observed activated platelets extending filopodia at sites of inter-EC gaps. In contrast, embryos lacking the activatory C-type lectin domain family 1, member b (CLEC1B) showed extravascular platelets and an excessive number of RBCs associated with and engulfed by the first lymphatic EC clusters that subsequently form lumenized blood-filled vessels connecting to the lymphatic system. These results uncover novel functions of platelets in maintaining venous integrity and lymphatic vessels in clearing extravascular RBCs during developmental remodeling of the mesenteric vasculature. They further provide insight into how vascular abnormalities characterized by blood-filled lymphatic vessels arise.

  • 1167894.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Karalius, Antanas
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Yan, Mingdi
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kinetics and Thermodynamics of Dynamic Nitroaldol Systems in Neutral Aqueous MediaManuscript (preprint) (Other academic)
  • 1167895.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology. Ningbo RK Solar Tech. Ltd., China.
    Lundblad, Anders
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology. Mälardalen University, Västerås, Sweden.
    Campana, P. E.
    Benavente, F.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology. Mälardalen University, Sweden.
    Battery sizing and rule-based operation of grid-connected photovoltaic-battery system: A case study in Sweden2017In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 133, p. 249-263Article in journal (Refereed)
    Abstract [en]

    The optimal components design for grid-connected photovoltaic-battery systems should be determined with consideration of system operation. This study proposes a method to simultaneously optimize the battery capacity and rule-based operation strategy. The investigated photovoltaic-battery system is modeled using single diode photovoltaic model and Improved Shepherd battery model. Three rule-based operation strategies—including the conventional operation strategy, the dynamic price load shifting strategy, and the hybrid operation strategy—are designed and evaluated. The rule-based operation strategies introduce different operation parameters to run the system operation. multi-objective Genetic Algorithm is employed to optimize the decisional variables, including battery capacity and operation parameters, towards maximizing the system's Self Sufficiency Ratio and Net Present Value. The results indicate that employing battery with the conventional operation strategy is not profitable, although it increases Self Sufficiency Ratio. The dynamic price load shifting strategy has similar performance with the conventional operation strategy because the electricity price variation is not large enough. The proposed hybrid operation strategy outperforms other investigated strategies. When the battery capacity is lower than 72 kW h, Self Sufficiency Ratio and Net Present Value increase simultaneously with the battery capacity.

  • 1167896.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology. Ningbo RK Solar Tech. Ltd., China.
    Lundblad, Anders
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology. Mälardalen University, Sweden.
    Campana, Pietro Elia
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology. Mälardalen University, Sweden.
    Comparative Study of Battery Storage and Hydrogen Storage to Increase Photovoltaic Self-sufficiency in a Residential Building of Sweden2016In: PROCEEDINGS OF RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID (REM2016) / [ed] Yan, J Zhai, Y Wijayatunga, P Mohamed, AM Campana, PE, ELSEVIER SCIENCE BV , 2016, p. 268-273Conference paper (Refereed)
    Abstract [en]

    Photovoltaic (PV) is promising to supply power for residential buildings. Battery is the most widely employed storage method to mitigate the intermittence of PV and to overcome the mismatch between production and load. Hydrogen storage is another promising method that it is suitable for long-term storage. This study focuses on the comparison of self-sufficiency ratio and cost performance between battery storage and hydrogen storage for a residential building in Sweden. The results show that battery storage is superior to the hydrogen storage in the studied case. Sensitivity study of the component cost within the hydrogen storage system is also carried out. Electrolyzer cost is the most sensitive factor for improving system performance. A hybrid battery and hydrogen storage system, which can harness the advantages of both battery and hydrogen storages, is proposed in the last place.

  • 1167897.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Lundblad, Anders
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Campana, Pietro Elia
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Employing Battery Storage to Increase Photovoltaic Self-sufficiency in a Residential Building of Sweden2016In: CUE 2015 - APPLIED ENERGY SYMPOSIUM AND SUMMIT 2015: LOW CARBON CITIES AND URBAN ENERGY SYSTEMS, Elsevier, 2016, p. 455-461Conference paper (Refereed)
    Abstract [en]

    Photovoltaic (PV) or hybrid PV-battery systems are promising to supply power for residential buildings. In this study, the load profile of a multi apartment building in Gothenburg and the PV production profile under local weather conditions are compared and analyzed. Three different types of batteries, including lead acid, NaNiCl (Sodium-Nickel-Chloride) and Lithium ion, are studied in combination with the PV systems. It is found that Lithium ion battery system is superior in achieving higher Self-Sufficiency Ratio (SSR) with the same Life Cycle Cost (LCC). Achieving high SSR with the hybrid PV-battery system is unrealistic because of the seasonal mismatch between the load and electricity production profile. The capacity match between the PV and battery to maximize SSR was investigated, showing different trends under system LCC range of 0.1-40 Million SEK (1SEK approximate to 0.12USD). The system LCC should be lower than 10.6 Million SEK (at the SSR of 36%) in order to keep the payback time positive.

  • 1167898.
    Zhang, Yang
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Stritt, Simon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Martinez-Corral, Ines
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Laviña, Bàrbara
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Betsholtz, Christer
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Mäkinen, Taija
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Vascular Biology.
    Alternative lymphatic endothelial progenitor cells compensate for the loss of non-venous-derived progenitors to form mesenteric lymphatic vesselsManuscript (preprint) (Other academic)
  • 1167899.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Xie, Sheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Yan, Mingdi
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Dynamic Covalent Chemistry of Aldehyde Enamines: Bi(III) and Sc(III) catalysis of amine-enamine exchangeManuscript (preprint) (Other academic)
  • 1167900.
    Zhang, Yang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Xie, Sheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Yan, Mingdi
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Dynamic Covalent Chemistry of Aldehyde Enamines: Bi-III- and Sc-III-Catalysis of Amine-Enamine Exchange2017In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, no 49, p. 11908-11912Article in journal (Refereed)
    Abstract [en]

    The dynamic exchange of enamines from secondary amines and enolizable aldehydes has been demonstrated in organic solvents. The enamine exchange with amines was efficiently catalyzed by Bi(OTf)(3) and Sc(OTf)(3) (2mol%) and the equilibria (60mm) could be attained within hours at room temperature. The formed dynamic covalent systems displayed high stabilities in basic environment with <2% by-product formation within one week after complete equilibration. This study expands the scope of dynamic C-N bonds from imine chemistry to enamines, enabling further dynamic methodologies in exploration of this important class of structures in systems chemistry.

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