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  • 122101.
    Zhu, Yingming
    et al.
    Sichuan Univ, Inst New Energy & Low Carbon Technol, Chengdu 610065, Sichuan, Peoples R China..
    Wang, Fu
    Ningbo Univ, Fac Maritime & Transportat, Ningbo 315211, Zhejiang, Peoples R China.;Ningbo RX New Mat Tech Co Ltd, Ningbo 315200, Zhejiang, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Sichuan Univ, Inst New Energy & Low Carbon Technol, Chengdu 610065, Sichuan, Peoples R China..
    The Potential of Distributed Energy Resources in Building Sustainable Campus: The Case of Sichuan University2018In: 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. 582-585Conference paper (Refereed)
    Abstract [en]

    Distributed energy resources systems are decentralized, modular and more flexible technologies. These systems can comprise multiple generation and storage components. Sichuan University (SCU) has joined Global Urban Development program, and takes part in Sustainability Tracking, Assessment & Rating System, aims at a sustainable campus. So we investigated the potential of distributed energy resources, e.g. solar power, that can be used in SCU. Firstly, we build 4 micro-grids with a total 156 Kw PV capacities to collect the power generation data. The total roof area of SCU Jiangan campus is 165701 m(2), and the estimated installed capacity is 8.3MW-11.6MW. Based on this data, 33% similar to 46% power cost can be covered by PV power generation.

  • 122102. Zhu, Yinian
    et al.
    Shum, Ping
    Nanyang Techbological University, Singapore.
    Bay, Hui-Wen
    Yan, Min
    Nanyang Techbological University, Singapore.
    Yu, Xia
    Hu, Juanjuan
    Hao, Jianzhong
    Lu, Chao
    Strain-insensitive and high-temperature long-period gratings inscribed in photonic crystal fiber2005In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 30, no 4, p. 367-369Article in journal (Refereed)
  • 122103.
    zhu, yue
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    Applying lean philosophy to the redesign of service delivery process: A case study in the telecommunication industry2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Lean is an umbrella term for a powerful combination of techniques to maximize customer value by minimizing waste and achieving continuous flow through a sustainable culture of continuous improvement. The term ―lean is used in the U.S. for what was originally created as the "Toyota Production System" by the Japanese carmaker. It is so fashionable since it was born that it’s been widely used in the manufacturing industry during the past decades all over the world. No matter in the opinion of insiders or outsiders, this is a magical word stands for discovering and eliminating discreet wastes, reducing resources requirement and time demand for production, making the manufacturing process efficient and cost effective and eventually building the sustainable competitive advantage of the organization.

    There’s already a world of books discussing the implementations. But as for the service delivery process, especially within the telecom industry, there’s no qualitative research carried out to check the validation of lean tool yet. Most researchers still remain on the theoretical level, arguing and debating on the applicability. The objective of this research is to fill in this research niche, check the possibility of using lean tool, naming VSM, to study and redesign the service delivery process in a qualitative way. The research question comes to how to apply the tool in a qualitative way and exam the both sides of the coin.

    The author investigated on the service delivery process performance in the Business-As-Usual projects and the key performance indicators of the case company business unit to find out any inconsistencies. One of the powerful lean tools - VSM is used step by step, node by node to identify existing discreet wastes. Based on the lean philosophy and literature reviews, potential possible improvements are proposed to eliminate the wastes, afterwards an ideal new VSM is created, with which it is able to dramatically reduce the resources required to seize customer value, satisfy the same amount of customer demand, increase customer satisfaction, make the company focusing on continuous improvement, and in the end move the company to a higher position in the field with stronger competence to win more market share.

    This research work is conducted as a single case study under the lean philosophy by collecting and studying qualitative data using various semi-structured interviews and archival data analysis. Six applicable solutions to lead the organization lean is proposed, and based on which, a brand new Optimization Focus Matrix is introduced to have a broader applicability. Possible benefit, difficulties in implementation and potential risks are also presented. The thesis ends with conclusion, answer to the research questions and discussion on the thesis limitation & future research direction.

  • 122104.
    Zhu, Yunyi
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA.
    Epitope Mapping using Local Alignment Features2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Our immune system uses antibodies to neutralize pathogens such as bacteria and viruses. Antibodies bind to parts of foreign proteins with high efficiency and specificity. We call such parts epitopes. The identification of epitopes, namely epitope mapping, may contribute to various immunological applications such as vaccine design, antibody production and immunological diagnosis.

    Therefore, a fast and reliable method that can predict epitopes from the whole proteome is highly desirable.

     

    In this work we have developed a computational method that predicts epitopes based on sequence information. We focus on using local alignment to extract features from peptides and classifying them using Support Vector Machine. We also propose two approaches to optimize the features. Results show that our method can reliably predict epitopes and significantly outperforms some most commonly used tools.

     

  • 122105. Zhu, Z.
    et al.
    Höglund, Lars
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Larsson, H.
    Reed, R. C.
    Isolation of optimal compositions of single crystal superalloys by mapping of a material's genome2015In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 90, p. 330-343Article in journal (Refereed)
    Abstract [en]

    The multicomponent composition space pertinent to the single crystal nickel-based superalloys is mapped and searched, using computational modelling. A resolution of 0.1 wt.% for the alloying elements is assumed, consistent with manufacturing practice. Databases are constructed of alloy compositions which are predicted to be of promising microstructural architecture: e.g. equal fractions of the γ and γ′ phases. These may be regarded as maps - one might term them genomes - of this class of structural alloy. By combining the databases with additional composition-dependent property models, it is demonstrated that compositions can be identified which - subject to the accuracy and limitations of the sub-models - are likely to prove optimal, e.g. on the basis of their creep resistance, density and cost. The methods circumvent the need for the traditional empirically-driven approaches to alloy design.

  • 122106. Zhu, Z.
    et al.
    Zhou, Y. J.
    Kang, M. -K
    Krivoruchko, A.
    Buijs, N. A.
    Nielsen, Jens
    KTH, Centres, Science for Life Laboratory, SciLifeLab. Chalmers University of Technology, Technical University of Denmark.
    Enabling the synthesis of medium chain alkanes and 1-alkenes in yeast2017In: Metabolic engineering, ISSN 1096-7176, E-ISSN 1096-7184, Vol. 44, p. 81-88Article in journal (Refereed)
    Abstract [en]

    Microbial synthesis of medium chain aliphatic hydrocarbons, attractive drop-in molecules to gasoline and jet fuels, is a promising way to reduce our reliance on petroleum-based fuels. In this study, we enabled the synthesis of straight chain hydrocarbons (C7–C13) by yeast Saccharomyces cerevisiae through engineering fatty acid synthases to control the chain length of fatty acids and introducing heterologous pathways for alkane or 1-alkene synthesis. We carried out enzyme engineering/screening of the fatty aldehyde deformylating oxygenase (ADO), and compartmentalization of the alkane biosynthesis pathway into peroxisomes to improve alkane production. The two-step synthesis of alkanes was found to be inefficient due to the formation of alcohols derived from aldehyde intermediates. Alternatively, the drain of aldehyde intermediates could be circumvented by introducing a one-step decarboxylation of fatty acids to 1-alkenes, which could be synthesized at a level of 3 mg/L, 25-fold higher than that of alkanes produced via aldehydes.

  • 122107. Zhu, Zhi-Shuang
    et al.
    Liao, Hua
    Cao, Huai-Shu
    Wang, Lu
    Wei, Yi-Ming
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    The differences of carbon intensity reduction rate across 89 countries in recent three decades2014In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 113, no SI, p. 808-815Article in journal (Refereed)
    Abstract [en]

    In the recent decades, most countries' CO2 intensity has decreased, but their decline rates are significantly different. Based on the data set of 89 countries from 1980 to 2008, this paper tries to quantitatively investigate the potential reasons for their differences, and discusses the possibility for developing countries to maintain a high carbon intensity reduction rate in the future as before. The econometric analysis implicate that (1) the decline rate of CO2 intensity in countries with high initial carbon intensity will be higher, which means CO2 intensity across the world has a significant convergence trend; and (2) keeping fast and steady economic growth can significantly help CO2 intensity decline, yet total carbon dioxide emissions will grow dramatically. Therefore, with the two objectives of intensity reduction and total amount control, carbon abatement policies need to weigh one against another. The results are robust to the initial year selection and country classification.

  • 122108. Zhu, Zhiwei
    et al.
    Zhou, Yongjin J.
    Krivoruchko, Anastasia
    Grininger, Martin
    Zhao, Zongbao K.
    Nielsen, Jens
    Expanding the product portfolio of fungal type I fatty acid synthases2017In: Nature Chemical Biology, ISSN 1552-4450, E-ISSN 1552-4469, Vol. 13, no 4, p. 360-362Article in journal (Refereed)
    Abstract [en]

    Fungal type I fatty acid synthases (FASs) are mega-enzymes with two separated, identical compartments, in which the acyl carrier protein (ACP) domains shuttle substrates to catalytically active sites embedded in the chamber wall. We devised synthetic FASs by integrating heterologous enzymes into the reaction chambers and demonstrated their capability to convert acyl-ACP or acyl-CoA from canonical fatty acid biosynthesis to short/ medium-chain fatty acids and methyl ketones.

  • 122109. Zhuang, C.
    et al.
    Marquez, Juan C.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. Shanghai Jiao Tong University, China.
    Qu, H. E.
    He, X.
    Lan, N.
    A neuromuscular electrical stimulation strategy based on muscle synergy for stroke rehabilitation2015In: International IEEE/EMBS Conference on Neural Engineering, NER, IEEE Computer Society, 2015, p. 816-819Conference paper (Refereed)
    Abstract [en]

    Recent experiments have suggested that the central nervous system (CNS) makes use of muscle synergies as a neural strategy to simplify the control of a variety of movements by using a single pattern of neural command signal. This nature of muscle coordination could have great significance in the treatment and rehabilitation of upper limb impairments for hemiparetic patients post stroke. The use of neuromuscular electrical stimulation (NMES) for neural prosthetics or therapeutic applications has been demonstrated as a promising clinical intervention for stroke patients to recover motor function of the upper extremity. However, the existing NMES systems do not provide control methods for the patient to achieve an individualized and functional rehabilitation training. In this research work, muscle synergies from the flexionextension elbow antagonistic muscles were studied. Using motion information and EMG signals, muscle synergies were extracted using non-negative matrix factorization (NMF) method. Reconstructed signals obtained from the muscle synergies were then applied to the virtual arm (VA) model to test a synergy based NMES strategy. Results show close resemblance to the original elbow trajectory of normal movements and thus the feasibility to control movements in stroke patients for rehabilitation.

  • 122110. Zhuang, F.
    et al.
    Shen, Jianqi
    KTH, School of Information and Communication Technology (ICT), Centres, Zhejiang-KTH Joint Research Center of Photonics, JORCEP.
    Ye, J.
    Controlling the photonic bandgap structures via manipulation of refractive index of electromagnetically induced transparency vapor2007In: Wuli xuebao, ISSN 1000-3290, Vol. 56, no 1, p. 541-545Article in journal (Refereed)
    Abstract [en]

    A new application of coherent manipulation of EIT (electromagnetically induced transparency) medium is suggested. A two-dimensional photonic crystal with a triangle lattice of elliptic air cylinders, which are filled with the EIT atomic vapor, in the KAs background material is designed. By manipulating the refractive index of the EIT vapor via the external control field, one can obtain the controllable bandgap structure that is sensitive to the variations of external conditions (e.g. the intensity of the control field) . It is shown that a large complete bandgap of about 0.0503ωe in the region of high normalized frequency could be achieved by choosing the specific parameters such as the spontaneous decay rate, dephasing rate, Rabi frequency of control light, atomic number density as well as elliptic geometric parameters.

  • 122111. Zhuang, F.
    et al.
    Wu, L.
    He, Sailing
    KTH, Superseded Departments, Electromagnetic Theory.
    A two-dimensional photonic crystal with six large bandgaps formed by a hexagonal lattice of anisotropic cylinders2002In: Chinese Physics (Beijing), ISSN 1009-1963, E-ISSN 1741-4199, Vol. 11, no 8, p. 834-838Article in journal (Refereed)
  • 122112. Zhuang, F.
    et al.
    Wu, L.
    He, Sailing
    Band structures of two-dimensional photonic crystals with regular polygon cylinders calculated by linear operations2002In: Wuli xuebao, ISSN 1000-3290, Vol. 51, no 12, p. 2865-2870Article in journal (Refereed)
  • 122113. Zhuang, F.
    et al.
    Wu, L.
    Xiao, S. S.
    He, Sailing
    KTH, Superseded Departments, Electromagnetic Theory.
    Band structure of a two-dimensional photonic crystal with a triangular lattice of anisotropic elliptic cylinders2002In: Chinese Physics Letters, ISSN 0256-307X, E-ISSN 1741-3540, Vol. 19, no 1, p. 73-75Article in journal (Refereed)
  • 122114.
    Zhuang, Hao
    KTH, School of Information and Communication Technology (ICT).
    Performance Evaluation of Virtualization in Cloud Data Center2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Amazon Elastic Compute Cloud (EC2) has been adopted by a large number of small and medium enterprises (SMEs), e.g. foursquare, Monster World, and Netflix, to provide various kinds of services. There has been some existing work in the current literature investigating the variation and unpredictability of cloud services. These work demonstrated interesting observations regarding cloud offerings. However, they failed to reveal the underlying essence of the various appearances for the cloud services.

    In this thesis, we looked into the underlying scheduling mechanisms, and hardware configurations, of Amazon EC2, and investigated their impact on the performance of virtual machine instances running atop. Specifically, several instances with the standard and high-CPU instance families are covered to shed light on the hardware upgrade and replacement of Amazon EC2. Then large instance from the standard family is selected to conduct focus analysis. To better understand the various behaviors of the instances, a local cluster environment is set up, which consists of two Intel Xeon servers, using different scheduling algorithms.

    Through a series of benchmark measurements, we observed the following findings: (1) Amazon utilizes highly diversified hardware to provision different instances. It results in significant performance variation, which can reach up to 30%. (2) Two different scheduling mechanisms were observed, one is similar to Simple Earliest Deadline Fist (SEDF) scheduler, whilst the other one analogies Credit scheduler in Xen hypervisor. These two scheduling mechanisms also arouse variations in performance. (3) By applying a simple "trial-and-failure" instance selection strategy, the cost saving is surprisingly significant. Given certain distribution of fast-instances and slow-instances, the achievable cost saving can reach 30%, which is attractive to SMEs which use Amazon EC2 platform.

  • 122115.
    Zhuang, Qingyuan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Parametric Study on the Aeroelastic Stability of Rotor Seals2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Labyrinth seals are widely used in rotating machinery and have been shown to experience aeroelastic instabilities. The rapid development of computational fluid dynamics now provides a high fidelity approach for predicting the aeroelastic behavior of labyrinth seals in three dimension and exhibits great potential within industrial application, especially during the detailed design stages. In the current publication a time-marching unsteady Reynolds- averaged Navier-Stokes solver was employed to study the various historically identified parameters that have essential influence on the stability of labyrinth seals. Advances in understanding of the related aeroelastic (flutter) phenomenon were achieved based on extensive yet economical numerical analysis of a simplified seal model. Further, application of the same methodology to several realistic gas turbine labyrinth seal designs confirmed the perceived knowledge and received agreements from experimental indications. Abbott’s criteria in describing the labyrinth seal aeroelastic behaviors were reaffirmed and further developed. 

  • 122116. Zhuang, Zanyong
    et al.
    Chen, Hong
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Lin, Zhang
    Dang, Zhi
    Mn2O3 hollow spheres synthesized based on an ion-exchange strategy from amorphous calcium carbonate for highly efficient trace-level uranyl extraction2016In: ENVIRONMENTAL SCIENCE-NANO, ISSN 2051-8153, Vol. 3, no 6, p. 1254-1258Article in journal (Refereed)
    Abstract [en]

    Well-defined hierarchical hollow spheres constructed from Mn2O3 quantum dots were prepared via an ion-exchange strategy starting from small-sized amorphous calcium carbonate. They show outstanding capability to extract trace-level uranyl from field water.

  • 122117. Zhukavin, R. Kh
    et al.
    Kovalevsky, K. A.
    Orlov, M. L.
    Tsyplenkov, V. V.
    Bekin, N. A.
    Yablonskiy, A. N.
    Yunin, P. A.
    Pavlov, S. G.
    Abrosimov, N. V.
    Huebers, H. -W
    Radamson, Henry H.
    KTH, School of Information and Communication Technology (ICT), Integrated Devices and Circuits.
    Shastin, V. N.
    Terahertz-range spontaneous emission under the optical excitation of donors in uniaxially stressed bulk silicon and SiGe/Si heterostructures2015In: Semiconductors (Woodbury, N.Y.), ISSN 1063-7826, E-ISSN 1090-6479, Vol. 49, no 1, p. 13-18Article in journal (Refereed)
    Abstract [en]

    The results of measurements of the total terahertz-range photoluminescence of Group-V donors (phosphorus, antimony, bismuth, arsenic) in bulk silicon and SiGe/Si heterostructures depending on the excitation intensity are presented. The signal of bulk silicon was also measured as a function of uniaxial stress. The results of measurement of the dependence of the spontaneous emission intensity on the uniaxial stress is in rather good agreement with theoretical calculations of the relaxation times of excited states of donors in bulk silicon. Comparative measurements of the spontaneous emission from various strained heterostructures showed that the photoluminescence signal is caused by donor-doped silicon regions.

  • 122118. Zhukovskii, Y. F.
    et al.
    Kotomin, E. A.
    Herschend, B.
    Hermansson, Kersti
    KTH, Superseded Departments, Biotechnology.
    Jacobs, P. W. M.
    The adhesion properties of the Ag/alpha-Al2O3(0001) interface: an ab initio study2002In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 513, no 2, p. 343-358Article in journal (Refereed)
    Abstract [en]

    Ab initio computer simulations of the atomic and electronic structure of the Ag/alpha-Al2O3(0 0 0 1) (corundum) interface have been performed for a periodic two-dimensional slab model using the Hartree-Fock method and a posteriori electron correlation corrections. We have considered both Al- and O-terminated corundum substrate surfaces. The dependence of the adhesion energy on the interfacial distance has been analyzed for the two most favorable Ag adsorption positions over corundum and for two different metal coverages (a 1/3 monolayer (NIL) of the Ag(l 1 1) crystallographic plane and a full Ag(I 1 1) monolayer). The two different terminations (Al- and O-) give rise to qualitatively different results. The former case corresponds to the most stable termination of the pure corundum (0 0 0 1) substrate where small adhesion energies per Ag atom (0.15-0.25 eV for I ML and 0.40-0.55 eV for 1/3 NIL) are accompanied by minor interfacial charge transfer, indicating physisorption, which may be explained by a weak atomic polarization. In contrast, for O-terminated corundum, substantial adhesion energies (3-5 eV per Ag atom at I ML coverage and 6-11 eV for 1/3 ML) combined with noticeable charge transfer from silver atoms towards the substrate (0.5e to 0.9e) are clear indications of a strong interfacial ion bonding. For both terminations, the observed difference in Ag adhesion energies for 1/3 NIL and I NIL coverages arises from a transition from directed Ag-O bonding towards a more delocalized electron density distribution in the complete monolayer. The results of our calculations are compared with available experimental studies and theoretical simulations for various Me/Al2O3 interfaces.

  • 122119. Zhuo, S.
    et al.
    Shokri-Ghadikolaei, Hossein
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Fischione, Carlo
    KTH, School of Electrical Engineering (EES), Automatic Control. KTH, School of Electrical Engineering (EES), Centres, ACCESS Linnaeus Centre.
    Wang, Z.
    Adaptive congestion control in cognitive industrial wireless sensor networks2015In: Proceeding - 2015 IEEE International Conference on Industrial Informatics, INDIN 2015, IEEE conference proceedings, 2015, p. 900-907Conference paper (Refereed)
    Abstract [en]

    Strict quality of service requirements of industrial applications, challenged by harsh environments and huge interference especially in multi-vendor sites, demand incorporation of cognition in industrial wireless sensor networks (IWSNs). In this paper, a distributed protocol of light complexity for congestion regulation in cognitive IWSNs is proposed to improve the channel utilization while ensuring predetermined performance for specific devices, called primary devices. By sensing the congestion level of a channel with local measurements, a novel congestion control protocol is proposed by which every device decides whether it should continue operating on the channel, or vacate it in case of saturation. Such a protocol dynamically changes the congestion level based on variations of non-stationary wireless environment as well as traffic demands of the devices. The proposed protocol is implemented on STM32W108 chips that offer IEEE 802.15.4 standard communications. Experimental results confirm substantial performance enhancement compared to the original standard, while imposing almost no signaling/computational overhead. In particular, channel utilization is increased by 56% with fairness and delay guarantees. The presented results provide useful insights on low-complexity adaptive congestion control mechanism in IWSNs.

  • 122120.
    Ziadi, Ahmed
    KTH, School of Computer Science and Communication (CSC).
    Facebook som komplement till modersmålsundervisning2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Facebook is the most widely used social media in Sweden. It allows the user to easily share the latest from their everyday life, their opinions, as well as communicate with their acquaintances. According to the latest poll from the Foundation for Internet Infrastructure, 33% of teenagers in the ages 12-15 spend their Internet time being active on social media. 63% of these teenagers visit Facebook on daily basis.

    Herein, we examined how Facebook can be exploited as a complement to the education of the mother tongue. The investigation was performed with a questionnaire as well as a test group that has been supplemented with semi-structured interviews. 

    In conclusion, the study showed promising results in the usage of Facebook with the education. By taking parts in discussions on Facebook, the students did not only improve their discussion abilities but also the writing. It was also observed that the communication between student and teacher was greatly improved. A remarkable observation was that students grown up in Sweden were more in favour for the use of Facebook as an educational tool than students grown up outside of Sweden.

  • 122121.
    Ziakouli, Marina
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Fagerberg, Erika
    KTH, School of Architecture and the Built Environment (ABE), Architecture, Urban Design.
    RIN♀EBY - Exploring feminist design tools2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This project aims on exploring ways to redefine the relationship of gender and space through urban design. Gender inequalities expressed in spatial manners have been theorized by feminist geography, an approach to human geography. Having a good understanding of this theoretical context will provide the tools to tackle distantiation, spatial separation, constraint and the limited spatial opportunities women experience in public places. Using Rinkeby square as the canvas for this exploration, the effort will be put on mapping the uses of the square through observation, quantitative research, as well as interviews with local organisations, shops and authorities close to the square. An inventory of the architectural features of the square will be made along with a site analysis focusing on the questions of effects on equality. Furthermore existing female networks and societies in the area will be contacted seeking possible collaborations for a later project work, workshops or events. Finally, as a result of the initial investigations, this project intends to explore how a physical intervention would affect these questions at Rinkeby square. It is the working hypothesis of this project that any project in order to be successful would need to be based on a deeper understanding of the challenges surrounding female presence on the square, and be tied into the already existing networks for women. This project therefore hopes to establish contact with existing female networks such as (D)Järva Kvinnor, Café Respekt and Tensta-Hjulsta Kvinnocenter, amongst others.

  • 122122. Zibar, Darko
    et al.
    Caballero, Antonio
    Yu, Xianbin
    Pang, Xiaodan
    RISE ACREO AB; Technical University of Denmark.
    Dogadaev, Anton K
    Monroy, I Tafur
    Hybrid optical fibre-wireless links at the 75–110 GHz band supporting 100 Gbps transmission capacities2011In: 2011 IEEE International Topical Meeting on Microwave Photonics - Jointly Held with the 2011 Asia-Pacific Microwave Photonics Conference, MWP/APMP 2011, 2011, p. 445-449, article id 6088767Conference paper (Refereed)
    Abstract [en]

    We present a photonic generation and down-conversion method for realizing a 40Gbps wireless link at the 75-110 GHz band exploiting the recent advances in photonic coherent detection technologies and digital signal processing. Furthermore, we analyze the capacities of hybrid optical fiber-wireless links at the 75-110GHz band, and propose several approaches to overcome the challenges towards 100Gbps wireless capacity.

  • 122123. Zibar, Darko
    et al.
    Sambaraju, Rakesh
    Caballero, Antonio
    Herrera, Javier
    Westergren, Urban
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Walber, Achim
    Jensen, Jesper Beevense
    Marti, Javier
    Monroy, Idelfonso Tafur
    High-Capacity Wireless Signal Generation and Demodulation in 75-to 110-GHz Band Employing All-Optical OFDM2011In: IEEE Photonics Technology Letters, ISSN 1041-1135, E-ISSN 1941-0174, Vol. 23, no 12, p. 810-812Article in journal (Refereed)
    Abstract [en]

    We present a radio-frequency (RF) and bit-rate scalable technique for multigigabit wireless signal generation based on all-optical orthogonal frequency-division multiplexing (OFDM) and photonic up-conversion. Coherent detection supported by digital signal processing is used for signal demodulation and data recovery. In order to demonstrate the RF frequency scalability and bit-rate transparency, the system is tested at 60 GHz and in the 75- to 110-GHz band at the baud rates of 5 and 10 Gbaud. In terms of the bit rate, the proposed system is experimentally tested up to 40 Gb/s for wireless signal generation and demodulation. The wireless transmission is not considered in this letter. Additionally, a novel digital carrier phase/frequency recovery structure is employed to enable robust phase and frequency tracking between the beating lasers.

  • 122124.
    Zichi, Julien
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    NbTiN for improved superconducting detectors2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The physics of single photons is fascinating, by manipulating them we can observe and probe quantum effects. Doing so requires the fabrication and utilization of single photon sources, of which many types have been developed including quantum dots, trapped atoms and ions, and color centers. On the other end of the experiments, single photon detectors play a role of utmost importance, and while several types of detectors exist, superconducting nanowire single photon detectors are now the state-of-the-art technology. By offering near unity detection efficiency from the ultra-violet to the mid-infrared light spectrum, with negligible noise and excellent time resolution, they made possible many experiments that were previously technologically unfeasible. The same appealing characteristics have found a use in applications outside of the quantum optics framework, with notably light detection and ranging, biomedical imaging or CMOS circuits testing.In this thesis a controlled growth method for tailoring the characteristics of niobium titanium nitride in the framework of superconducting nanowire single photon detectors was developed. Reactive co-sputter deposition of niobium titanium nitride was shown to be a versatile method, both in terms of the degree of control over the material composition, and in the choice of substrates that it allows. Unity internal detection efficiency of detectors at telecom wavelengths was achieved by optimizing the niobium content in the material. The influence of lattice matching on the critical temperatures of films deposited at room temperature was investigated. The fabrication of superconducting nanowire single photon detectors on aluminum nitride-on-sapphire, on lithium niobate nano-waveguides, on gallium arsenide, and the integration on SiN waveguides was achieved. The material was used to fabricate detectors with optimized response for any linear polarization of the incoming photons by using a fractal architecture. Another method was proposed to achieve the same results by encapsulating meandering detectors in a high index dielectric material, resulting in a decrease of the permittivity mismatch between the nanowire material and its surrounding and therefore optimizing the efficiency for both orthogonal linear polarizations.Finally, detectors were fabricated from films developed in this work, and were operated to enable the implementation of polarization-based entanglement distribution in optical fibers in a real-conditions scenario, over a record distance of 96 km. This paves the way for the development of quantum communication networks using existing optical fiber links.

  • 122125.
    Zichi, Julien
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Chang, Chang
    Steinhauer, Stephan
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    von Fieandt, Kristina
    Los, Johannes W. N.
    Visser, Gijs
    Kalhor, Nima
    Lettner, Thomas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Elshaari, Ali W.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Esmaeil Zadeh, Iman
    Zwiller, Val
    NbxTi1-xN low timing jitter single-photon detectors with unity internal detection efficiency at 1550 nmManuscript (preprint) (Other academic)
    Abstract [en]

    The requirements in quantum optics experiments for high single photon detectionefficiency, low timing jitter, low dark count rate and short dead time have been fulfilled withthe development of superconducting nanowire single photon detectors. Although they offer adetection efficiency above 90%, achieving a high time resolution in devices made ofamorphous materials is a challenge, particularly at temperatures above 0.8 K. Devices madefrom niobium nitride and niobium titanium nitride allow to reach the best timing jitter, but inturn have stronger requirements in terms of film quality to achieve a high efficiency. Here wetake advantage of the flexibility of reactive co-sputter deposition to tailor the composition ofNbxTi1-xN superconducting films, and show that a Nb fraction of x = 0.62 allows for thefabrication of detectors from films as thick as 9 nm and covering an active area of 20 μm,with a wide detection saturation plateau at telecom wavelengths and in particular at 1550 nm.This is a signature of an internal detection efficiency saturation, achieved while maintainingthe high time resolution associated with NbTiN and operation at 2.5K. With our optimizedrecipe, we reliably fabricated detectors with high critical current densities reaching asaturation plateau at 1550 nm with 80% system detection efficiency, and with a FWHMtiming jitter as low as 19.47 ps.

  • 122126.
    Zichi, Julien
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Gyger, Samuel
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Baghban, Mohammad Amin
    Elshaari, Ali W.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Gallo, Katia
    Zwiller, Val
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    An NbTiN superconducting single photon detector implemented on a LiNbO3 nano-waveguide at telecom wavelength2019In: Poster session T.Po2, 2019Conference paper (Refereed)
    Abstract [en]

    Fiber-coupled superconducting nanowire single photon detectors are a ubiquitous tool for quantum optics experiments as they offer near unity detection efficiency over a broad wavelength range, low dark count rate, excellent time resolution and high saturation rate. Nevertheless, advancing quantum optics experiments and applications beyond the few-photon limit requires large scale integrated systems of quantum sources and detectors. In recent years there has been a tremendous progress with integrating single photon detectors with a variety of photonic platforms. This includes attempts on ion-diffused waveguides in LiNbO3, a non-linear and electro-optic material with widespread use for signal processing, frequency conversion, and quantum optics devices. However the realization of superconducting detectors on single mode waveguides remains elusive. Here we present an NbTiN superconducting single photon detector integrated directly on a LiNbO3 single mode nanophotonic waveguide at telecom wavelength, with a high critical current density and a dark count rate of 3 mHz at 99% of its critical current.

  • 122127.
    Zichi, Julien
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Yang, Lily
    Gyger, Samuel
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Lettner, Thomas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Errando-Herranz, Carlos
    KTH, School of Electrical Engineering and Computer Science (EECS), Micro and Nanosystems.
    Jöns, Klaus D.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Baghban, Mohammad Amin
    Gallo, Katia
    Steinhauer, Stephan
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Zwiller, Val
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum and Biophotonics.
    Heterogeneous integration of NbTiN by universal room temperature depositionManuscript (preprint) (Other academic)
    Abstract [en]

    Being the Nb-based compound with the highest known critical temperature, NbTiN is of particular interest for many applications. It is used in Josephson junctions for single flux quantum logic gates, as a superconducting electrode to contact semiconductor devices, and one important use is in superconducting nanowire single photon detectors. These detectors are the ideal candidate for on-chip integration in photonic circuits, offering near-unity detection efficiency, low noise and excellent time resolution, therefore it is desirable to implement them on a wide variety of platforms. However, it remains a challenge to deposit the superconducting material with a process suitable for heterogeneous integration, as the most widespread material, NbN, is associated with a deposition at a high temperature. Taking advantage of the possibility to deposit superconducting NbTiN with various stoichiometries by co-sputter deposition at room temperature, we demonstrate growth on six different substrates – silicon dioxide, silicon nitride, gallium arsenide, lithium niobate, [Pb(Mg1/3Nb2/3)O3]-x[PbTiO3] or PMN-PT, and aluminum nitride – in the same deposition run, and show that all the films exhibit superconducting properties with similar critical temperatures. We fabricated waveguide-compatible superconducting nanowire single photon detectors on five substrates, report short dead times for all devices with a narrow spread of performances, and discuss their different photon detection saturation behavior. Our method simplifies the fabrication of superconducting devices on a wide range of materials.

  • 122128.
    Zickerman, Linnéa
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Cirkushallen i Alby: Balans2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Mitt kandidatprojekt är ett förslag till en Cirkushall i Alby där Cirkus Cirkör verkar. Projektet handlar om att skapa och forma en identitet till en stadsdel, exponera en verksamhet och att forma en byggnad efter de behov en cirkusverksamhet efterfrågar. 

  • 122129.
    Zickerman, Linnéa
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Vetenskapen: - En Forskningsstation i Tarfala2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the beginning of the 20th century the glaciers in the world got smaller. Scientists couldn’t explain why but tried to find a connection between climate change and melting glaciers. One of them, V. Schytt, made a ski journey between Abisko and Kebnekaise to find the most suitable glacier in Sweden for measuring mass balance. He faced the windy, rough but beautiful valley “Tarfaladalen”. He viewed over ”Storglaciaciaren” and realized that this site is optimal for a glacier research center.

    Since 1946 the Stockholm University founded a research station where both national researcher as well as international visits and uses as a platform. The data that is collected around this area is important information for glacier studies around the world. We are facing huge climate changes in the world and the Department of Geological Science in Tarfala are in need of a more complex building adapted to the extreme environment that gives the best support to practise science and research at an international high level. During my thesis project I have analyzed the site, the wind and the organisation Department of Geological Science in Tarfala.

  • 122130.
    Zickert, Gustav
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    Furstenberg's conjecture and measure rigidity for some classes of non-abelian affine actions on tori2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In 1967 Furstenberg proved that the set {2n3mα(mod 1) | n, m ∈N} is dense in the circle for any irrational α. He also made the following famous measure rigidity conjecture: the only ergodic measures on the circle invariant under both x —> 2x and x —> 3x are the Lebesgue measure and measures supported on a finite set. In this thesis we discuss both Furstenberg’s theorem and his conjecture, as well as the partial solution of the latter given by Rudolph. Following Matheus’presentation of Avila’s ideas for a proof of a weak version of Rudolph’s theorem, we prove a result on extending measure preservation from a semigroup action to a larger semigroup action. Using this result we obtain restrictions on the set of invariant measures for certain classes of non-abelian affine actions on tori. We also study some general properties of affine abelian and non-abelian actions and we show that analogues of Furstenberg’s theorem hold for affine actions on the circle.

  • 122131.
    Zickert, Gustav
    KTH, School of Engineering Sciences (SCI).
    On Algebraic Numbers and Quadratic Extensions2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract.

    In this thesis some basic properties of algebraic el-

    ements, integral elements and extensions of rings and elds are

    investigated. Special focus is given to quadratic extensions. It is

    assumed that the reader is familiar with some elementary concepts

    from abstract algebra, such as the denitions of rings and elds.

    The rst section covers the basics of algebraic elements and in-

    tegral elements and serves as a foundation for the rest of the thesis.

    In section two and three some theory of Unique Factorization Do-

    mains and Euclidean Domains is developed. The concepts and

    results from these two sections are used in section four and ve,

    which treat Quadratic Extensions and certain Ring Extensions of

    the integers.

  • 122132.
    Zickert, Gustav
    et al.
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    Maretzke, Simon
    Univ Gottingen, Inst Numer & Appl Math, Gottingen, Germany..
    Cryogenic electron tomography reconstructions from phaseless data2018In: Inverse Problems, ISSN 0266-5611, E-ISSN 1361-6420, Vol. 34, no 12, article id 124001Article in journal (Refereed)
    Abstract [en]

    We perform three-dimensional (3D) reconstructions from simulated and real cryogenic electron tomography (cryo-ET) data. Our reconstructions are based on a nonlinear and phaseless forward model very reminiscent of a commonly used model for phase contrast x-ray tomography.

  • 122133. Zieba, A.
    et al.
    Ponten, F.
    Uhlén, Mathias
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Landegren, U.
    In situ protein detection with enhanced specificity using DNA-conjugated antibodies and proximity ligation2018In: Modern Pathology, ISSN 0893-3952, E-ISSN 1530-0285, Vol. 31, no 2, p. 253-263Article in journal (Refereed)
    Abstract [en]

    Antibodies are important tools in anatomical pathology and research, but the quality of in situ protein detection by immunohistochemistry greatly depends on the choice of antibodies and the abundance of the targeted proteins. Many antibodies used in scientific research do not meet requirements for specificity and sensitivity. Accordingly, methods that improve antibody performance and produce quantitative data can greatly advance both scientific investigations and clinical diagnostics based on protein expression and in situ localization. We demonstrate here protocols for antibody labeling that allow specific protein detection in tissues via bright-field in situ proximity ligation assays, where each protein molecule must be recognized by two antibodies. We further demonstrate that single polyclonal antibodies or purified serum preparations can be used for these dual recognition assays. The requirement for protein recognition by pairs of antibody conjugates can significantly improve specificity of protein detection over single-binder assays.

  • 122134.
    Zieba, Agata
    et al.
    Uppsala Univ, Dept Immunol Genet & Pathol, Sci Life Lab, S-75185 Uppsala, Sweden..
    Sjöstedt, Evelina
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Olovsson, Matts
    Uppsala Univ, Dept Womens & Childrens Hlth, S-75185 Uppsala, Sweden..
    Fagerberg, Linn
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Hallström, Björn M.
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Oskarsson, Linda
    Uppsala Univ, Dept Immunol Genet & Pathol, Sci Life Lab, S-75185 Uppsala, Sweden..
    Edlund, Karolina
    Uppsala Univ, Dept Immunol Genet & Pathol, Sci Life Lab, S-75185 Uppsala, Sweden..
    Tolf, Anna
    Uppsala Univ, Dept Immunol Genet & Pathol, Sci Life Lab, S-75185 Uppsala, Sweden..
    Uhlén, Mathias
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ponten, Fredrik
    Uppsala Univ, Dept Immunol Genet & Pathol, Sci Life Lab, S-75185 Uppsala, Sweden..
    The Human Endometrium-Specific Proteome Defined by Transcriptomics and Antibody-Based Profiling2015In: Omics, ISSN 1536-2310, E-ISSN 1557-8100, Vol. 19, no 11, p. 659-668Article in journal (Refereed)
    Abstract [en]

    The human uterus includes the complex endometrial mucosa, the endometrium that undergoes dynamic, hormone-dependent alterations throughout the life of fertile females. Here we have combined a genome-wide transcriptomics analysis with immunohistochemistry-based protein profiling to analyze gene expression patterns in the normal endometrium. Human endometrial tissues from five women were used for deep sequencing (RNA-Seq). The mRNA and protein expression data from the endometrium were compared to 31 (RNA) and 44 (protein) other normal tissue types, to identify genes with elevated expression in the endometrium and to localize the expression of corresponding proteins at a cellular resolution. Based on the expression levels of transcripts, we could classify all putative human protein coding genes into categories defined by expression patterns and found altogether 101 genes that showed an elevated pattern of expression in the endometrium, with only four genes showing more than five-fold higher expression levels in the endometrium compared to other tissues. In conclusion, our analysis based on transcriptomics and antibody-based protein profiling reports here comprehensive lists of genes with elevated expression levels in the endometrium, providing important starting points for a better molecular understanding of human reproductive biology and disease.

  • 122135.
    Ziegenhagen, Stephanie
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Mathematics (Div.).
    En-cohomology with coefficients as functor cohomology2016In: Algebraic and Geometric Topology, ISSN 1472-2747, E-ISSN 1472-2739, Vol. 16, no 5, p. 2981-3004Article in journal (Refereed)
    Abstract [en]

    Building on work of Livernet and Richter, we prove that En -homology and En - cohomology of a commutative algebra with coefficients in a symmetric bimodule can be interpreted as functor homology and cohomology. Furthermore, we show that the associated Yoneda algebra is trivial.

  • 122136. Zielińska, J. A.
    et al.
    Zukauskas, A.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Canalias, Carlota
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Noyan, M. A.
    Mitchell, M. W.
    Fully-resonant, tunable, monolithic frequency conversion as a coherent UVA source2017In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 25, no 2, p. 1142-1150Article in journal (Refereed)
    Abstract [en]

    We demonstrate a monolithic frequency converter incorporating up to four tuning degrees of freedom, three temperature and one strain, allowing resonance of pump and generated wavelengths simultaneous with optimal phase-matching. With a Rb-doped periodically-poled potassium titanyl phosphate (KTP) implementation, we demonstrate efficient continuous-wave second harmonic generation from 795 to 397, with low-power efficiency of 72% and high-power slope efficiency of 4.5%. The measured performance shows good agreement with theoretical modeling of the device. We measure optical bistability effects, and show how they can be used to improve the stability of the output against pump frequency and amplitude variations. 

  • 122137. Zientkiewicz, Jacek K.
    et al.
    Lach, Zbigniew T.
    Grabiec, Piotr
    Driessen, Alfred
    Jaskorzynska, Bozena
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Quantum Electronics and Quantum Optics, QEO (moved to SCI 2011-07-01).
    Wosinski, Lech
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics (Closed 20120101), Quantum Electronics and Quantum Optics, QEO (moved to SCI 2011-07-01).
    A roadmap to a technological platform for integrating nanophotonic structures with micromechanical systems in silicon-on-insulator2005In: Integrated Optics: Theory and Applications / [ed] Pustelny T., Lambeck P.V., Gorecki C., SPIE - International Society for Optical Engineering, 2005, p. 59560H-Conference paper (Refereed)
    Abstract [en]

    On the foundation of joint experience acquired by several research centres there was defined the roadmap to the desired single technological platform for fabrication of a specific class of photonic integrated circuits, which are controlled by mechanical means. In the paper the challenges of fabrication of such photonic circuits are discussed. The main arguments in favour of the Silicon-on-Insulator materials system as the basis for the platform are presented. Options for the mechanics-to-optics arrangement, materials and processes are described and illustrated with the current achievements from the authors' labs. In the roadmap the preference is given to the vertical arrangement in which, the mechanical part is stacked above the waveguiding layer. A flexible trimming routine is designed to complement the process flow if the technologies developed cannot provide the required reproducibility.

  • 122138. Zierkiewicz, W.
    et al.
    Privalov, Timofei
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    A computational study of oxidation of ruthenium porphyrins via ORuIV and (ORuO)-O-VI species2006In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, no 15, p. 1867-1874Article in journal (Refereed)
    Abstract [en]

    An unrestricted density functional theory (UDFT) was applied to study the oxidation of ruthenium porphyrins, [RuP], via an interaction with molecular oxygen. The important role of dimeric [ RuP] complexes, i.e. [RuP]-O-2-[RuP], in the oxidation mechanism and particular in the cleavage of O-O bond of molecular oxygen has been studied. Geometries and relative Gibbs free energies of the intermediate Ru-complexes, i.e. dimeric oxo-Ru-porphyrins and O2RuII-(or O-2(-) Ru-III)-, ORuIV- and (ORuO)-O-VI-porphyrins, were evaluated along the proposed reaction pathway. The detailed thermodynamic data of the oxidation reaction [(RuP)-P-II] -> O[(RuP)-P-IV] -> O[(RuP)-P-VI]O and important aspects of the vibrational spectra of an oxo-[RuP] has been presented.

  • 122139. Zierkiewicz, W.
    et al.
    Privalov, Timofei
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    A theoretical study of the essential role of DMSO as a solvent/ligand in the Pd(OAc)(2)/DMSO catalyst system for aerobic oxidation2005In: Organometallics, ISSN 0276-7333, E-ISSN 1520-6041, Vol. 24, no 24, p. 6019-6028Article in journal (Refereed)
    Abstract [en]

    Dimethyl sulfoxide (DMSO) has unique properties as an aprotic, polar solvent. The oxygen atom in DMSO can interact with positive charges and thus stabilize metal cation. The sulfur atom, although somewhat positively charged, does not interact with negative charges effectively. Also, two methyl groups surround the sulfur atom and influence binding properties of DMSO. These features of DMSO are addressed in the present computational study of the Pd(AcO)(2)/DMSO-catalyzed aerobic oxidation system. Mechanistic and computational details are provided. The step-by-step Gibbs energy of reaction was calculated using the electronic energy at the B3LYP density functional level with thermal functions calculated at the same level of theory. The solvent was modeled using the polarized medium (PCM) with additional DMSO molecules in the second coordination sphere of the complexes studied. The overall reaction pathway was divided into several steps in accord with available experimental data. All steps, including the first deprotonation and the beta-hydride elimination transition states, were elucidated in good detail. Coordination and reorganization of DMSO in Pd(II)(AcO)(2)/DMSO and Pd(0)/(DMSO)(n) complexes has been studied to provide realistic data about coordination of DMSO with hard (O) versus soft (S) ligand donor atoms. The P-hydride elimination transition state was identified computationally to give an estimation of the activation energy of the alcohol oxidation reaction. Therefore, we suggest that the rate-determining step is related to the alcohol part of the reaction cycle.

  • 122140.
    Ziethén, Andreas
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Analys av QoS i mellanvaran Meteor2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is closely related to the Dynamically Self-Configuring Automotive System (DySCAS) project. DySCAS is a middleware for electronics in an automotive system. The thesis work has been performed in cooperation with ENEA. Parts of the demonstration platform Self configurable High Availability and Policy based platform for Embedded system (SHAPE) developed for the DySCAS project by ENEA have been used in the implementation phase of this master thesis. The goal of this thesis was to evaluate how the Meteor MW, an offspring of the DySCAS middleware, should handle QoS and to design a Quality of Service Manager (QoSM) for the Meteor MW that fulfilled hard real-time requirements. The thesis also had the objective of analysing and identifying the requirements on such a QoSM from a QoS perspective. Specifically the requirements to guarantee real-time support for applications running on the MW. Lastly this thesis had the goal of evaluating other existing MW having support for real-time requirements. In this thesis the aforementioned QoSM was designed and partially implemented. An application model of a typical Med Tech system was used to derive requirements necessary for the QoSM. Existing MWs such as HADES and ARMADA were also analyzed to help determine the necessary requirements on the designed MW. These requirements were used to design the QoSM. The resulting QoSM has support for both real-time requirements and high bandwidth communication. Its main functionality is scheduling of network traffic on an Ethernet bus. The scheduling algorithm is interchangeable but only one algorithm has been implemented in this thesis. The implemented algorithm is priority based. Interesting areas for future work were also identified such as further development of the QoSM. This development includes QoS levels, different scheduling algorithms and linking the scheduling to other resources outside the network. 

  • 122141. Zietz, Burkhard
    et al.
    Gabrielsson, Erik
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Johansson, Viktor
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    El-Zohry, Ahmed M.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Photoisomerization of the cyanoacrylic acid acceptor group - a potential problem for organic dyes in solar cells2014In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 16, no 6, p. 2251-2255Article in journal (Refereed)
    Abstract [en]

    Organic solar cell dyes containing the most common anchoring group, cyanoacrylic acid, are shown to be photolabile and undergo photoisomerization. This may have significant consequences for dye-sensitized solar cells, as isomerisation competes with electron injection and leads to modifications of the dye and surface arrangement.

  • 122142. Zika-Viktorsson, A.
    et al.
    Ritzén, Sofia
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Integrated Product Development.
    Project competence in product development2005In: Research in Engineering Design, ISSN 0934-9839, E-ISSN 1435-6066, Vol. 15, no 4, p. 193-200Article in journal (Refereed)
    Abstract [en]

    This paper presents and discusses the individual competence particularly required to work in project-organized product development. Individual competence encompasses the knowledge, skills and abilities to deal with issues related to organizational, social and technological factors involved in projects. The purpose has been to explore the competence required for project members at the operational level, and to explore the conditions for developing such competence. The study is based on a qualitative approach, with interviews as the tool for data collection. The study group comprised 54 respondents working in RTD departments within five large Swedish manufacturing companies. The findings reveal the need for project co-workers to be skilled in both practical and psychosocial aspects of co-ordination, time planning and control. The findings of the study demonstrate the importance of being able to cope with prescribed as well as unpredictable processes. They also indicate the effect of time on experience transfer.

  • 122143.
    Zika-Viktorsson, Annika
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Integrated Product Development.
    Interorganisatorisk samverkan kring samhällsutmaningar och digitala lösningar: En studie av programmet Digital Demo Stockholm2018Report (Other academic)
    Abstract [sv]

    Interorganisatorisk samverkan enligt trippelhelixmodellen är ett sätt att möta komplexa samhällsutmaningar och att lösa problem. Komplexiteten i problemen ställer krav på samverkan mellan behovsägare och experter samt med de som har de resurser som krävs för att lösningar ska förverkligas. Rapporten presenterar en studie av interorganisatorisk samverkan i programmet Digital Demo Stockholm (DDS). Det är ett program som genomförs av KTH tillsammans med partners från näringsliv och offentlig sektor och som arbetar för att möta samhällsutmaningar i Stockholmsregionen. Inom programmet bedrivs forsknings- och innovationsprojekt som tar fram digitala lösningar och demonstratorer. Programmet bygger på långsiktigt partnerskap mellan Stockholms stad, Stockholms Läns Landsting, KTH, ABB, Ericsson, Skanska, Scania, Vattenfall och Telia. På sikt ska programmet leda till ett samhälle som är hållbart och attraktivt och att Stockholm år 2040 är ”världens smartaste stad”. Resultaten baseras på intervjuer med initiativtagare till programmet och projektledare för demoprojekten samt på enkäter till medarbetare i demoprojekten och ledamöter i programmets rådsfunktioner. Studien är kvalitativ och alla utsagor och svar har analyserats med en kvalitativ ansats. Frågorna i studien rör deltagarnas inställning till programmet och till arbetet på den övergripande programnivån liksom i demoprojekten. Studien undersöker och beskriver deltagares uppfattning om DDS. Syftet har inte varit att utvärdera programmets olika delar utan att med en explorativ ansats beskriva vad som uppfattas som viktiga försättningar för samverkan. En viktig förutsättning är det engagemang som präglat arbetet i programmet och som delvis har en koppling till möjligheten att arbeta för samhällsnytta och organisatoriska innovationer. En annan är ett ledarskap som är agilt, entreprenöriellt och sammanhållande. De krav som ställs på att driva ett initiativ som DDS liknar de som ”start-up-verksamheter” ställer på drift och ledning. För att komma framåt krävs anpassning samtidigt med stora mått av uthållighet, en mångfald av kompetenser och utveckling på programmets samtliga nivåer.

  • 122144.
    Zika-Viktorsson, Annika
    KTH, Superseded Departments, Machine Design.
    The industrial project. Studies of the work situation of project members2002Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [sv]

    The aim of the thesis was to investigate and analyze howproject members at operative level experience industrialproject work. The project goal, alongside the time limits,methods applied, and cooperation, were envisaged to set theprerequisites for the work situation. Four empirical studies,based on both qualitative and quantitative methods, areencompassed by this thesis. In total, 31 companies and 298respondents were involved in the studies. The studies wereperformed in product-development and construction settingswithin the mechanical engineering industry. The analysis showsthat project work is characterized by: 1) Goal-focusedcooperation in flexible and changeable work groups. Demandscompetence for cooperation; interaction and communicationconstantly adjusted to problem-solving processes; and jointactivities for goal definition. 2) Treating time as a resource.A fast pace of work demands shared responsibilities in a team;unconstrained interaction and communication; and socialsupport. Scarce time resources give rise to the risk ofneglecting needs for long-term knowledge development. 3)Development and insecurity. Development makes contingency-basedsupervision and planning needed, together with team-basedplanning and goal formulation. High levels of developmentstimulate knowledge and improvements to routines and practices.Technological development also entails insecurity, whichrequires the ability mentally to cope with flexibility andcontinuous adjustments.

    Keywords:Project organization, Project work, Projectmanagement, Project team, Product development, Constructionprojects, Psychosocial work environment.

  • 122145.
    Zika-Viktorsson, Annika
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Ingelgård, Anders
    Reflecting activities in product developing teams: conditions for improved project management processes2006In: Research in Engineering Design, ISSN 0934-9839, E-ISSN 1435-6066, Vol. 17, no 2, p. 103-111Article in journal (Refereed)
    Abstract [en]

    The study presented in this paper was designed to investigate the relationship between psychosocial aspects of project work and team-based activities that enable reflection upon project teams' own practices. The study includes 144 project-active product developers in 20 Swedish manufacturing companies. Data were collected by means of a questionnaire survey. The main question addressed was how individual project members' psychosocial work environment is related to participation and involvement in team-based reflecting activities. A further question was whether reflectivity in local project teams is related to improvement to overarching processes. The results show that three of the tested factors promote reflectivity in project teams, such as a high level of project work experience, a high level of time pressure, and extensive managerial support. It is also shown that reflecting activity at local project team level is associated with improvement to project management processes at a more general level.

  • 122146.
    Zika-Wiktorsson, Annika
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.).
    Sundström, Per
    KTH, School of Technology and Health (STH).
    Engwall, Mats
    VINNOVA, Swedish Governmental Agency for Innovation Systems.
    Project Overload: An Exploratory Study of Work and Management in Multi-Project Settings2006In: International Journal of Project Management, ISSN 0263-7863, E-ISSN 1873-4634, Vol. 24, no 5, p. 385-394Article in journal (Refereed)
    Abstract [en]

    This study investigates psychosocial aspects of work in multi-project settings and how project members and project managers at operational level perceive their work situation. Work in a multi-project setting entails a complicated situation characterized by tight schedules, multi-tasking, increased coordination expenditures, and a large amount of set-up time when alternating between tasks. The study addresses the issue of project overload, a construct that in this study reflects perceived fragmentation, disruption and inefficiency, caused by switching between assignments for separate but simultaneous projects. An explorative approach was adopted for the study, and new models were created and investigated. The primary source of data was a web-based questionnaire. The questionnaire was administered to project co-workers (n = 392) in nine companies in Sweden (response rate: 81%). The companies represented manufacturing, pharmaceutical and construction industries, and all occupied a leading position on their respective markets. The results show that almost one-third of the respondents were under perceived project overload, and that 21% (p ≤ .001) of the variance on this variable could be explained by four factors. In order of magnitude, these factors were: (1) lack of opportunities for recuperation, (2) inadequate routines, (3) scarce time resources, and (4) a large number of simultaneous projects. Further, the study indicated that there are associations between high level of project overload and (a) high levels of psychological stress reactions, (b) decreased competence development, and (c) deviations from time schedules.

  • 122147.
    Zikeli, Florian
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. Technische Universität Wien, Austria.
    Ters, T.
    Fackler, K.
    Srebotnik, E.
    Li, Jiebing
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Wheat straw lignin fractionation and characterization as lignin-carbohydrate complexes2016In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 85, p. 309-317Article in journal (Refereed)
    Abstract [en]

    Alkaline extracted and untreated wheat straw were ball-milled with liquid nitrogen cooling rendering them completely soluble in the solvent system dimethylsulfoxide-aqueous tetrabutylammonium hydroxide for subsequent fractionation into two lignin-carbohydrate complex fractions termed glucan-lignin and xylan-lignin according to their preferred association with glucan or arabinoxylan, respectively. This is the first description using this fractionation protocol for wheat straw. Eventually, acidolysis lignins were prepared from both lignin-carbohydrate complexes and structurally characterized using wet chemistry and NMR spectroscopy methods. Using the novel procedure we could reveal differences regarding wheat straw lignin association with polysaccharides, p-hydroxycinnamic acids and tricin as well as in their monomer composition. In glucan-lignin the lignin moiety was found to be linked mainly to glucan but also to branched arabinoxylan. Xylan-lignin, however, was rich in structures creating cross-links between lignin and linear arabinoxylan via ether-ester bridges by bi-functional ferulic acid. Inter-molecular ether-ester-linkages by ferulic acid connecting the lignin moieties of the two LCC fractions glucan-lignin and xylan-lignin were proposed. Alkaline extraction of the straw resulted in a strikingly lower recovery of xylan-lignin in the subsequent fractionation which was attributed to cleavage of ester linkages between ferulic acid and arabinoxylan. Structural characteristics indicated glucan-lignin and xylan-lignin deriving from different morphological origins of the cell wall.

  • 122148. Zikeli, Florian
    et al.
    Ters, Thomas
    Fackler, Karin
    Srebotnik, Ewald
    Li, Jiebing
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Fractionation of wheat straw Dioxane lignin reveals molar mass dependent structural differences2016In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 91, p. 186-193Article in journal (Refereed)
    Abstract [en]

    Dioxane lignin was isolated from ball-milled wheat straw by neutral dioxane-water extraction and subsequently molar-mass-fractionated by flash chromatography in dimethylformamide. The eluted lignin containing material was pooled into six distinct molar mass fractions that were in turn structurally characterized in detail by wet chemistry and NMR spectroscopy methods. Fractions of higher molar mass were found to be enriched in p-hydroxyphenyl units and contained more p-hydroxycinnamic acid units. They were found mainly associated with linear arabinoxylan, while in low-molar-mass fractions additional glucan contributions were found. Fractions of lower molar mass consisted of relatively more guaiacyl units and showed exclusive association with tricin units. One distinct lignin fraction with lower lignin content supposedly contained high ratios of arabinoxylan chains esterified by ferulic acid and cross-linked via ferulic acid dimerization, structures which were considered to represent lignin nucleation sites. High abundance of dibenzodioxocin type structures in this fraction indicated that they could be involved in cross-linking hemicelluloses networks with lignin moieties.

  • 122149.
    Zikeli, Florian
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. Vienna University of Technology, Austria.
    Ters, Thomas
    Fackler, Karin
    Srebotnik, Ewald
    Li, Jiebing
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Successive and quantitative fractionation and extensive structural characterization of lignin from wheat straw2014In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 61, p. 249-257Article in journal (Refereed)
    Abstract [en]

    A unique process for the fractionation of lignin from wheat straw is proposed: Ball milling for 8 h, followed by a direct and an acidolysis-assisted dioxane-water extraction. Four distinctly different lignin structures were thus obtained: (1) one free non-core lignin, which is a cellulose-lignin with lowest molar mass and highest contents of p-hydroxycinnamic acids, condensed phenolic hydroxyl groups and tricin moieties, and with a detectable amount of cinnamyl alcohols; (2) two core xylan-lignins differing in their degree of branching as indicated by their xylose/arabinose ratios of >4 and similar to 2, respectively; (3) one core cellulose-lignin which is the residual fraction resistant to all extractions. Based on the mass balance of Klason lignin the yields of these four fractions are 13.8%, 18.1%, 37.5% and 12.5%, respectively, thus accounting for 82% of the total KL in wheat straw. Therefore, the isolated lignin fractions could be considered as highly representative allowing a good insight into the different features of wheat straw lignin.

  • 122150.
    Zikopi, Eleni
    KTH, School of Electrical Engineering and Computer Science (EECS).
    A case study research on Scrum Framework2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Agile methods have been widely implemented in the industry while teaching these methods is a substantial part of Computer Science and Engineering program curricula. Evidencedriven data of agile practices, methods, and tools have been extracted based on empirical studies with students, however, there is an important need for more anecdotal evidence to confirm these findings. In order to fill this gap, this paper explores the perceptions and the applicability of the Scrum Framework in a student research team in an industrial context. Empirical data have been gathered through interviews with the case study participants combined with a survey. The analysis reveals that student experiences are mainly positive and that they can easily grasp the benefits of Scrum Framework. The challenges of implementing Scrum in such a setting mainly concern the balance between coach and self-organization, formulating accurate user stories when researching, finding the most suitable estimation method, as well as planning when conducting research. The empirical findings may potentially be extrapolated in student scrum teams or even in industrial settings. Finally, this research paper should encourage other researchers to investigate the adoption of Scrum in a student setting.

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