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  • 45101.
    Zhu, B.
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Hedman, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Li, Haibo
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Design digital mindfulness for personal wellbeing2016Ingår i: Proceedings of the 28th Australian Computer-Human Interaction Conference, OzCHI 2016, Association for Computing Machinery, Inc , 2016, 626-627 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    The digital health and wellbeing movement has led to development of what we here baptize as digital mindfulness applications that allow people to improve psychological wellbeing. The approaches to digital mindfulness vary greatly and as a researcher it can be difficult to gain an overview of the field and what to focus on in one's own research. Here we describe four levels of digital mindfulness with examples and focus on the larger question of how to design for digital mindfulness. We end up with a set of general issues that we hope will generate further discussion and research in the field of digital mindfulness. 

  • 45102.
    Zhu, Bin
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID. Hubei Univ.
    Li, Haibo
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Designing finger movement on mobile phone touch screen for rich emotional expression2014Ingår i: 2014 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference, APSIPA 2014, IEEE conference proceedings, 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Emotional expression is significant as an essential part in our daily life. Ubiquitous presence of mobile technology-mediated communication creates various affective occasions and affords rich emotional expressions with lower complexity of input. In this paper, we aim to design a simple way of emotional expression through finger movements on mobile phone touch screen allowing for richer affective expressivities. We categorize the visual representations into four types according to their modality and then raised a schema that including three core properties of touch-screen based finger movement dynamics. From design practice, we find the form and property of visual representation shapes the experience of expression and the way finger moves. Kinesthetic representation with its dynamic property can reflect the core properties of finger movement and thus afford the rich expressivity in presenting emotional experience. Thus, we indicate that simple finger movements based on mobile phone touch screens can express rich emotional experience. Moreover, we suggest designing appropriate and corresponding properties of visual representation regarding to the properties of finger movement as a meaningful and expressive material. © 2014 Asia-Pacific Signal and Information Processing Ass.

  • 45103.
    Zhu, Chunsheng
    et al.
    Univ British Columbia, Dept Elect & Comp Engn, Vancouver, BC V5Z 1M9, Canada..
    Leung, Victor C. M.
    Univ British Columbia, Dept Elect & Comp Engn, Vancouver, BC V5Z 1M9, Canada..
    Ngai, Edith C. -H.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Yang, Laurence T.
    St Francis Xavier Univ, Dept Comp Sci, Antigonish, NS, Canada..
    Shu, Lei
    Guangdong Univ Petrochem Technol, Guangdong Prov Key Lab Petrochem Equipment Fault, Maoming, Peoples R China..
    Li, Xiuhua
    Univ British Columbia, Dept Elect & Comp Engn, Vancouver, BC V5Z 1M9, Canada..
    Pricing Models for Sensor-Cloud2015Ingår i: 2015 IEEE 7Th International Conference On Cloud Computing Technology And Science (Cloudcom), 2015, 454-457 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Incorporating ubiquitous wireless sensor networks (WSNs) and powerful cloud computing (CC), Sensor-Cloud (SC) is attracting growing attention from both academia and industry. However, pricing for SC is barely explored. In this paper, filling this gap, five SC pricing models (i.e., SCPM1, SCPM2, SCPM3, SCPM4 and SCPM5) are proposed first. Particularly, they charge a SC user, based on 1) the lease period of the user; 2) the required working time of SC; 3) the SC resources utilized by the user; 4) the volume of sensory data obtained by the user; 5) the SC path that transmits sensory data from the WSN to the user, respectively. Further, analysis is also presented to study and demonstrate the performance of the proposed SCPMs. We believe that the pricing designs and analysis performed in this work could be a very valuable guidance for future researches regarding pricing in SC.

  • 45104. Zhu, Chunsheng
    et al.
    Leung, Victor C. M.
    Shu, Lei
    Ngai, Edith C.-H.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Green Internet of Things for Smart World2015Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 3, 2151-2162 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Smart world is envisioned as an era in which objects (e.g., watches, mobile phones, computers, cars, buses, and trains) can automatically and intelligently serve people in a collaborative manner. Paving the way for smart world, Internet of Things (IoT) connects everything in the smart world. Motivated by achieving a sustainable smart world, this paper discusses various technologies and issues regarding green IoT, which further reduces the energy consumption of IoT. Particularly, an overview regarding IoT and green IoT is performed first. Then, the hot green information and communications technologies (ICTs) (e.g., green radio frequency identification, green wireless sensor network, green cloud computing, green machine to machine, and green data center) enabling green IoT are studied, and general green ICT principles are summarized. Furthermore, the latest developments and future vision about sensor cloud, which is a novel paradigm in green IoT, are reviewed and introduced, respectively. Finally, future research directions and open problems about green IoT are presented. Our work targets to be an enlightening and latest guidance for research with respect to green IoT and smart world.

  • 45105.
    Zhu, Di
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Large Scale ETL Design, Optimization and Implementation Based On Spark and AWS Platform2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Mängden data som genereras internet-produkt-användare ökar lavinartat och exponentiellt. Det finns otaliga exempel på detta; klick-strömmen från hemsidor med miljontals användare, geospatial information från GISbaserade Android och iPhone appar, eller från sensorer på autonoma bilar.Mängden händelser från de här typerna av data kan enkelt uppnå miljardantal dagligen, därför är det föga förvånande att det är möjligt att extrahera insikter från de här data-strömmarna. Till exempel kan man sätta upp automatiserade övervakningssystem eller kalibrera bedrägerimodeller effektivt. Att handskas med data i de här storleksordningarna är dock inte helt problemfritt, det finns flertalet tekniska bekymmer som enkelt kan uppstå. Datan är inte alltid på samma form, den kan vara av olika dimensioner vilket gör det betydligt svårare att designa en effektiv data-pipeline, transformera datan och lagra den persistent i ett data-warehouse. Onekligen finns det traditionella sätt att bygga ETL’s på från mainframe [1], RDBMS, till MapReduce och Hive. Dock har det med upptäckten och ökade populariteten av Spark och AWS blivit mer robust, effektivt, billigare och enklare att implementera system för att samla data, bygga dimensions-enliga modeller och genomföra analys av massiva data-set. Den här uppsatsen bidrar till en ökad förståelse kring hur man bygger och optimerar ETL-pipelines baserade på AWS och Spark och jämför med huvudsakliga nuvarande Data-pipelines med hänsyn till diverse aspekter. Uppsatsen drar nytta av att ha tillgång till ett massivt data-set med miljarder användar-events genererade dagligen från ett bil-transport-bolag i mellanöstern.

  • 45106.
    Zhu, Huan
    Blekinge Tekniska Högskola, Sektionen för teknik, Avdelningen för programvarusystem.
    Investigation and Evaluation of Object Oriented Analysis techniques2004Självständigt arbete på avancerad nivå (magisterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    The technique of Object Oriented Analysis (OOA) has emerged only in the last decade. Although the technique of OOA is still new, its popularity has been increasing and it has already entered the mainstream of object oriented system development. This thesis makes a summary of four OOA methods and investigates the behaviors of all methods under different criteria. Through comparing the four methods, differences between methods are shown and analysts can select the appropriate one to meet his/her requirements.

  • 45107.
    Zhu, Jun
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Energy and Design Cost Efficiency for Streaming Applications on Systems-on-Chip2009Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    With the increasing capacity of today's integrated circuits, a number ofheterogeneous  system-on-chip (SoC)  architectures  in embedded  systemshave been proposed. In order to achieve energy and design cost efficientstreaming applications  on these  systems, new design  space explorationframeworks  and  performance  analysis  approaches are  required.   Thisthesis  considers three state-of-the-art  SoCs architectures,  i.e., themulti-processor SoCs (MPSoCs)  with network-on-chip (NoC) communication,the hybrid CPU/FPGA architectures, and the run-time reconfigurable (RTR)FPGAs.  The main topic of the  author?s research is to model and capturethe  application  scheduling,  architecture  customization,  and  bufferdimensioning  problems, according to  the real-time  requirement.  Sincethese  problems  are NP-complete,  heuristic  algorithms and  constraintprogramming solver are used to compute a solution.For  NoC  communication  based  MPSoCs,  an  approach  to  optimize  thereal-time    streaming    applications    with   customized    processorvoltage-frequency levels and memory  sizes is presented. A multi-clockedsynchronous  model  of  computation   (MoC)  framework  is  proposed  inheterogeneous  timing analysis and  energy estimation.   Using heuristicsearching  (i.e., greedy  and  taboo search),  the  experiments show  anenergy reduction (up to 21%)  without any loss in application throughputcompared with an ad-hoc approach.On hybrid CPU/FPGA architectures,  the buffer minimization scheduling ofreal-time streaming  applications is addressed.  Based  on event models,the  problem  has  been  formalized  decoratively  as  constraint  basescheduling,  and  solved  by  public domain  constraint  solver  Gecode.Compared  with  traditional  PAPS  method,  the  proposed  method  needssignificantly smaller  buffers (2.4%  of PAPS in  the best  case), whilehigh throughput guarantees can still be achieved.Furthermore, a  novel compile-time analysis approach  based on iterativetiming  phases is  proposed  for run-time  reconfigurations in  adaptivereal-time   streaming   applications  on   RTR   FPGAs.   Finally,   thereconfigurations analysis and design trade-offs analysis capabilities ofthe proposed  framework have been  exemplified with experiments  on bothexample and industrial applications.

  • 45108.
    Zhu, Jun
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektroniksystem.
    Performance Analysis and Implementationof Predictable Streaming Applications onMultiprocessor Systems-on-Chip2010Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Driven by the increasing capacity of integrated circuits, multiprocessorsystems-on-chip (MPSoCs) are widely used in modern consumer electron-ics devices. In this thesis, the performance analysis and implementationmethodologies are explored to design predictable streaming applications onMPSoCs computing platforms. The application functionality and concur-rency are described in synchronous data flow (SDF) computational models,and two state-of-the-art architecture templates are adopted as multiproces-sor architectures, i.e., network-on-chip (NoC) based MPSoC and hybrid re-configurable CPU/FPGA platforms. Based on the author’s contributions onsimulation and formal analytical methods, performance analysis and designspace exploration for embedded MPSoCs architectures have been addressed.

    An energy efficient design space exploration flow is proposed for stream-ing applications with guaranteed throughput on NoC based MPSoCs, in whichboth application throughput analysis and system energy calculation are car-ried out by simulation on a multi-clocked synchronous modelling frame-work. On the other hand, based on event models of data streams, a formalanalytical scheduling framework for real-time streaming applications withminimal buffer requirement on hybrid CPU/FPGA architectures is exploited.The scheduling problem has been formalized declaratively by constraint basetechniques, and solved by a public domain constraint solver. Consecutively,the constraint based method has been extended to solve problems rangingfrom global computation/communication scheduling and reconfiguration anal-ysis to Pareto efficient design. Finally, a prototype of stream processing sys-tem on FPGA based MPSoC is built to substantiate the results from theoreti-cal studies in this thesis.

  • 45109.
    Zhu, Jun
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Sander, Ingo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Jantsch, Axel
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Buffer Minimization of Real-Time Streaming Applications Scheduling on Hybrid CPU/FPGA Architectures2009Ingår i: DATE: 2009 DESIGN, AUTOMATION & TEST IN EUROPE CONFERENCE & EXHIBITION, 2009, 1506-1511 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    We address the problem of real-time streaming applications scheduling on hybrid CPU/FPGA architectures. The main contribution is a two-step approach to minimize the buffer requirement for streaming applications with throughput guarantees. A novel declarative way of constraint based scheduling for real-time hybrid SW/HW systems is proposed, while the application throughput is guaranteed by periodic phases in execution. We use a voice-band modem application to exemplify the scheduling capabilities of our method. The experimental results show the advantages of our techniques in both less buffer requirement and higher throughput guarantees compared to the traditional PAPS method.

  • 45110.
    Zhu, Jun
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektroniksystem.
    Sander, Ingo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektroniksystem.
    Jantsch, Axel
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektroniksystem.
    Constrained Global Scheduling of Streaming Applications on MPSoCs2010Ingår i: 2010 15TH ASIA AND SOUTH PACIFIC DESIGN AUTOMATION CONFERENCE (ASP-DAC 2010), 2010, 223-228 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present a global scheduling framework for synchronous data flow (SDF) streaming applications on MPSoCs, based on optimized computation and contention-free routing. The global scheduling of processors computing and communication transactions are formulated as constraint based problem, to avoid the scheduling overhead in TDMA-like heuristic schemes. A public domain constraint solver is exploited to solve the NP-complete scheduling efficiently, together with problem specific constraint modeling techniques. Experimental results show that the proposed framework can achieve a high predictable application throughput with minimized buffer cost. For instance, for applications in communication domain, higher throughput (up to 87%) has been observed with less buffer cost, compared to scenarios considering the heuristic scheduling overhead.

  • 45111.
    Zhu, Jun
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Sander, Ingo
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Jantsch, Axel
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Elektronik- och datorsystem, ECS.
    Performance Analysis of Reconfiguration in Adaptive Real-Time Streaming Applications2008Ingår i: PROCEEDINGS OF THE 2008 IEEE/ACM/IFIP WORKSHOP ON EMBEDDED SYSTEMS FOR REAL-TIME MULTIMEDIA / [ed] Eles P; Pimentel AD, 2008, 53-58 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    We propose a design optimization framework for adaptive real-time streaming applications. The main contribution is a hybrid approach for performance analysis combining formal analysis and simulation using a two-phase framework. We formulate the scheduling problem of adaptive streaming applications with ILP analysis, and use the simulation based on the synchronous model of computation to ensure throughput guarantees. We finally illustrate the capabilities of our methodology by experiments.

  • 45112.
    Zhu, Lei
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Security Extensions of the OpenStack Platform2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The emergence of Cloud Computing has become one of hottest topics in IT industry. So, what is cloud computing? There are many definitions summarized by people from different areas in their perspectives. However, the US National Institute of Standard Technology (NIST) [1] defines cloud computing as a model for enabling ubiquitous, convenient, ondemand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) [2].

    Despite of all the benefits that Cloud Computing brings to the IT industry, there are increasing issues being pointed out about the security and privacy due to the currently immature cloud security status. NIST points out that there are several security and privacy issues in the area of public cloud computing including governance, authentication, access control, data protection and availability [3].

    This master thesis is intended to build security architecture for open-source cloud computing platform. This thesis work concentrates on providing strong authentication service between cloud provider and users, as well as delivering access control and Single- Sign-On (SSO) service to the users, which are provided by the central security system. The central security system, as the proposed solution for secure cloud-computing platform, comprises of different security components providing security services in the form of web services. OpenStack as an open-source cloud-computing platform is chose for the research.

  • 45113.
    Zhu, Lin
    KTH, Skolan för informations- och kommunikationsteknik (ICT).
    DESIGN AND IMPLEMENTATION A BATTERY MANAGEMENT SYSTEM FOR A MULTI‐FUNCTION POWER CONVERTER2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis work designed and implemented an advanced Battery Management System (BMS) for a battery package with 96 Lithium-ion battery cells connected in series. The focus of this thesis placed on battery model building, battery balancing algorithm developing, State-of-Charge (SOC) estimation algorithm developing, and implementing software in microprocessor.A set of simulation program is developed to verify the battery model and the algorithms. A battery simulator based on SPICE is built to implement a first order Thevenin dynamic electrochemical model. PID control algorithm is employed in balancing the battery cells. Meanwhile, Extended Kalman Filter (EKF) algorithm is used for estimating the SOC. An interactive web GUI application is also developed for easy control. Software running on STM32F103 microprocessor has been developed to adapt the existing BMS hardware.The simulation result proves that the first order Thevenin dynamic electrochemical model reflect the behavior of a real battery accurately, the PID balancing algorithm is effective to make the battery cells stay in balanced state and the error of EKF SOC estimation algorithm is below 5%.

  • 45114.
    Zhu, Mingjie
    et al.
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Matematiska och systemtekniska institutionen.
    Liu, Qinghua
    Växjö universitet, Fakulteten för matematik/naturvetenskap/teknik, Matematiska och systemtekniska institutionen.
    XAP Integration2006Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats
    Abstract [en]

    Abstract

    This bachelor thesis will present the XAP tool integration project. Apart from presenting the survey of

    integration techniques that includes integration models and case tool models, we have conducted a

    comparison of these models. Then we reason about their applicability in the XAP setting. We apply this

    survey into the XAP tool integration project – integrate three tools in one IDE on data level. In this IDE,

    the user can create a new project and use these three tools freely in the new created project. The

    database among them is shared.

  • 45115.
    Zhu, Minpeng
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för datalogi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Scalable Queries over Log Database Collections2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In industrial settings, machines such as trucks, hydraulic pumps, etc. are widely distributed at different geographic locations where sensors on machines produce large volumes of data. The data produced is stored locally in autonomous databases called log databases. The collection of log databases is dynamically changing when new sites are dynamically added or removed from the federation.

    In this application context, an efficient way to search and analyze passed behavior of products in use is desired. To enable scalable queries over collections of distributed and autonomous log databases we developed the FLOQ (Fused LOg database Query processor) system, which provides a global view of the working status of all machines on the sites through a meta-database integrating the dynamic log database collection. A particular challenge in this scenario is a scalable way to process numerical queries that identify anomalies by joining data from the meta-database with data selected from the collection of distributed and autonomous log databases. The Thesis describes the architecture of FLOQ. In particular different strategies to execute numerical queries over log database collections are investigated. FLOQ allows both the meta-database and the log databases to be stored in multiple formats using different kinds of data managers. FLOQ provides general and extensible mechanisms for efficient processing of queries over different kinds of distributed data sources.

  • 45116.
    Zhu, Minpeng
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Mahmood, Khalid
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Risch, Tore
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datalogi.
    Scalable queries over log database collections2015Ingår i: Data Science, Springer, 2015, 173-185 s.Konferensbidrag (Refereegranskat)
  • 45117. Zhu, Minpeng
    et al.
    Risch, Tore
    Querying Combined Cloud-Based and Relational Databases2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    An increasing amount of data is stored in cloud repositories, which provide high availability, accessibility, and scalability. However, for security reasons enterprises often need to store the core proprietary data in their own relational databases, while common data to be widely available can be stored in a cloud data repository. For example, the subsidiaries of a global enterprise are located in different geographic places where each subsidiary is likely to maintain its own local database. In such a scenario, data integration among the local databases and the cloud-based data is inevitable. We have developed a system called BigIntegrator to enable general queries that combine data in cloud-based data stores with relational databases. We present the design and working principle of the system. A scenario of querying data from both kinds of data sources is used as illustration. The system is general and extensible to integrate data from different kinds of data sources. A particular challenge being addressed is the limited query capabilities of cloud data stores. BigIntegrator utilizes knowledge of those limitations to produce efficient query execution.

  • 45118. Zhu, Minpeng
    et al.
    Stefanova, Silvia
    Truong, Thanh
    Risch, Tore
    Scalable Numerical SPARQL Queries over Relational Databases2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present an approach for scalable processing of SPARQL queries to RDF views of numerical data stored in relational databases (RDBs). Such queries include numerical expressions, inequalities, comparisons, etc. inside FILTERs. We call such FILTERs numerical expressions and the queries - numerical SPARQL queries. For scalable execution of numerical SPARQL queries over RDBs, numerical operators should be pushed into SQL rather than executing the filters as post-processing outside the RDB; otherwise the query execution is slowed down, since a lot of data is transported from the RDB server and furthermore indexes on the server are not utilized. The NUMTranslator algorithm converts numerical expressions in numerical SPARQL queries into corresponding SQL expressions. We show that NUMTranslator improves substantially the scalability of SPARQL queries based on a benchmark that analyses numerical logs stored in an RDB. We compared the performance of our approach with the performance of other systems processing SPARQL queries to RDF views of RDBs and show that NUMTranslator improves substantially the scalability of numerical queries compared to the other systems’ approaches.

  • 45119.
    Zhu, Nanhao
    et al.
    CETC Group, GCI Science and Technology Co.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A generic framework for energy evaluation on wireless sensor networks2016Ingår i: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, nr 4, 1199-1220 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to reliance on batteries, energy consumption has always been of significant concern for sensor node networks. This work presents the design and implementation of a house-build experimental platform, named Energy Management System for Wireless Sensor Networks (EMrise) for the energy management and exploration on wireless sensor networks. Consisting of three parts, the SystemC-based simulation environment of EMrise enables the HW/SW co-simulation for energy evaluation on heterogeneous sensor networks. The hardware platform of EMrise is further designed to facilitate the realistic energy consumption measurement and calibration as well as accurate energy exploration. In the meantime, a generic genetic algorithm based optimization framework of EMrise is also implemented to automatically, quickly and intelligently fine tune hundreds of possible solutions for the given task to find the best suitable energy-aware tradeoffs

  • 45120.
    Zhu, Nanhao
    et al.
    CETC Group, GCI Science and Technology Co.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    EMrise: An Energy Management Platform for WSNs/WBANs2016Ingår i: Energy Management in Wireless Cellular and Ad-hoc Networks, Encyclopedia of Global Archaeology/Springer Verlag, 2016, 367-395 s.Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Due to reliance on batteries, energy consumption has always been of significant concern for sensor node networks. This work presents the design and implementation of a house-build experimental platform, named EMrise (Energy Management System for Wireless Sensor Networks) for the energy management and exploration on wireless sensor networks. Consisting of three parts, the SystemC-based simulation environment of EMrise enables the HW/SW co-simulation for energy evaluation on heterogeneous sensor networks. The hardware platform of EMrise is further designed to facilitate the realistic energy consumption measurement and calibration as well as accurate energy exploration. In the meantime, a generic GA (genetic algorithm) based optimization framework of EMrise is also implemented to automatically, quickly and intelligently fine tune hundreds of possible solutions for the given task to find the best suitable energy-aware tradeoffs.

  • 45121.
    Zhu, Peter
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    Deblurring Algorithms for Out-of-focus Infrared Images2010Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    An image that has been subject to the out-of-focus phenomenon has reducedsharpness, contrast and level of detail depending on the amount of defocus. Torestore out-of-focused images is a complex task due to the information loss thatoccurs. However there exist many restoration algorithms that attempt to revertthis defocus by estimating a noise model and utilizing the point spread function.The purpose of this thesis, proposed by FLIR Systems, was to find a robustalgorithm that can restore focus and from the customer’s perspective be userfriendly. The thesis includes three implemented algorithms that have been com-pared to MATLABs built-in. Three image series were used to evaluate the limitsand performance of each algorithm, based on deblurring quality, implementationcomplexity, computation time and usability.Results show that the Alternating Direction Method for total variation de-convolution proposed by Tao et al. [29] together with its the modified discretecosines transform version restores the defocused images with the highest qual-ity. These two algorithms include features such as, fast computational time, fewparameters to tune and a powerful noise reduction.

  • 45122.
    Zhu, Qiyao
    et al.
    Högskolan i Jönköping, Internationella Handelshögskolan, IHH, Informatik.
    Hu, Yan
    Högskolan i Jönköping, Internationella Handelshögskolan, IHH, Informatik.
    Guo, Wentao
    Högskolan i Jönköping, Internationella Handelshögskolan, IHH, Informatik.
    Mobile learning in higher education: Students’ acceptance of mobile learning in three top Chinese universities2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Introduction: Along with the swift spread of 3G and wireless network, wireless technologies are applied in many areas, especially in education. The advent of mobile learning overcomes several limitations and barriers of traditional classroom education. As for higher education in China, mobile learning is in its infancy stage. Understanding end-users’ acceptance of mobile learning is crucial, because new technological advances cannot enhance performance if they are not accepted by end-users. This study focuses on three top Chinese universities and answers the following research questions:

    1. How do students perceive mobile devices as a learning tool incorporated in class and what are their attitudes towards mobile learning?
    2. What are the motivational factors that affect students’ acceptance of mobile learning?

    Purpose: The purpose of this study is to test the proposed Technology Acceptance Model (TAM) in explaining students’ acceptance in three top Chinese universities. The goal of this work is to enhance the understanding of user acceptance of incorporating learning into mobile device inside and outside classes.

    Method: A deductive, theory-testing approach was used in this study. Eleven hypotheses were built based on a literature review and on the proposed TAM model, and were tested using primary data and literature review. Primary data was gathered via semi-structured interviews and questionnaires. The data collected through the questionnaire was analysed by Structural Equation Modeling.

    Conclusion: Through testing the proposed model, the authors found that students are positive towards mobile learning but they do not have a strong willingness to adopt it. The proposed TAM model can improve the understanding of students’ motivation by suggesting what factors are the most important in enhancing students acceptance of mobile learning.

  • 45123.
    Zhu, Rui
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Gidofalvi, Gyözö
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    GPS-based Crowd Sourced Intelligent Traffic Information Hub2013Ingår i: Proceedings of the 26th International Cartographic Conference / [ed] Manfred F. Buchroithner, ICC International Cartographic Association , 2013, 669-670 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Congestion is a major problem in most metropolitan areas and given the increasing rate of urbanization it is likely to be an even more serious problem in the rapidly expanding mega cities. Some well know negative effects of congestion include: 1) the economic losses and quality of life degradation that result from the increased and unpredictable travel times, 2) the increased level of carbon footprint that vehicles idling in congestions leave behind, and 3) the increased number of traffic accidents that are direct results of the stress and fatigue of drivers that are stuck in congestion.

    One possible method to combat congestion is provide intelligent traffic management systems that can in a timely manner inform drivers about current or predicted traffic congestion that is relevant to them on their journeys. This this extent, the present paper proposes a scalable, grid-based intelligent traffic information hub that facilitates the manual definition and/or automatic detection of abnormal traffic condition events, e.g., accidents or congestion, and in advance informs drivers about events that will likely be relevant to them on their journey, thereby allowing the divers or their onboard navigation units to alter their paths as needed.

    The proposed system achieves the above described functionality through the following methodology. The system, without loss of generality, adopts a grid-based discretization of space, which by changing the resolution of the grid allows the system to scale in terms of it computation cost and the geographical level of detail of traffic information that it manages. The system derives traffic information from the continuous stream of grid-based position and speed reports that it receives from the vehicles. In particular, the system in an online fashion 1) summarizes Current (grid-based) Traffic Flow Statistics (CTFS), i.e., it records for each grid cell g from each neighboring grid cell n, the mean and standard deviation of the speeds of the vehicles that are currently located in g and have entered g from n; and 2) efficiently incorporates the CTFS into compressed Historical (grid-based) Traffic Flow Statistics (HTFS) using incremental statistics. Simultaneously, using a sliding window model, the system also 1) maintains the Recent (grid-based) Trajectories (RT) of the vehicles; 2) extracts Recent (gridbased) Mobility Statistics (RMS), i.e., it records for each destination grid cell d, for each neighboring grid cell n of g, and for each possible source grid cell s, the number of vehicles that (i) are currently in d, (ii) have entered d from n, and (iii) have a RT that has passed through s; and 3) efficiently incorporates the RMS into compressed Historical (grid-based) Mobility Statistics (HMS) using incremental statistics. To capture the temporal variability in traffic flow and mobility patterns at different scales, the system through temporal domain projections maintains day-of-week and hour-ofday based aggregations of HTFS and RMS. Then, the system classifies a grid cell g to be congested from the direction of a neighboring grid cell n if the current mean speed of vehicles that entered the grid cell g from the direction of n is below the normal according to the temporally relevant HFS. Finally, based on the temporally relevant HMS, the system sends out congestion notifications to vehicles that are likely to be effected in the future part of their journey by these congestions, i.e., the system sends out a congestion notification (g,n) to a vehicle v that is currently located in some grid cell s from which the likelihood of v moving to g through n within the prediction horizon is above a user-defined threshold.

    Extensive empirical evaluations on large sets of realistically simulated trajectories of vehicles illustrate that the above described methodology and its simple SQL-based implementation in a relational database system is scalable and effective. In particular, the execution time of- and the space used by the system scales linearly with the input size (number of concurrently moving vehicles) and the method’s mutually dependent parameters (grid resolution r and RT length l) that jointly define a spatio-temporal resolution. Within the area of a large city (40km by 40km), assuming a 60km/h average vehicle speed, the system, running on a single personal computer, can manage the described congestion detection and one-minute-ahead notification tasks within real-time requirements for 15 thousand and 2.5 million concurrently moving vehicles for spatio-temporal resolutions (r=62.5m, l=17) and (r=4km,l=2), respectively. Finally, the proposed method, for all spatio-temporal resolutions and prediction horizons, significantly outperforms in terms of notification accuracy the grid-based baseline method, which sends non-directional congestion notifications based on the recent linear movement tendencies of vehicles. 

  • 45124.
    Zhu, Xudong
    et al.
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Li, Jun
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Gao, Xiaofeng
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Wu, Fan
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Chen, Guihai
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A distributed approximation for multi-hop clustering problem in wireless sensor networks2016Ingår i: 2015 IEEE Global Communications Conference (GLOBECOM): San Diego, CA, 6-10 Dec 2015, Piscataway, NJ: IEEE Communications Society, 2016, 7416941Konferensbidrag (Refereegranskat)
    Abstract [en]

    In wireless sensor networks (WSNs), there is no predefined infrastructure. Nodes need to frequently flood messages to discover routes, which badly decreases the network performance. To overcome such drawbacks, WSNs are often grouped into several disjointed clusters, each with a representative cluster head (CH) in charge of the routing process. In order to further improve the efficiency of WSNs, it is crucial to find a cluster partition with minimum number of clusters and the distance between each node to its corresponding CH can be bounded by a constant number of hops. Finding such a partition is defined as minimum d-hop cluster head set (d-MCHS) problem, which is proved to be NP-hard. In this paper, we propose a distributed approximation algorithm, named d^2-Cluster, to address d-MCHS problem and prove that the approximation ratio of d^2-Cluster under unit disk graph (UDG) is a constant factor \lambda which is related to d. To the best of our knowledge, it is the first constant approximation ratio for d-MDS problem in UDG

  • 45125. Zhu, Yuanwen
    et al.
    Jia, Wang
    Migrating the New Horizon website to WordPress2012Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    There are different problems associated with a static website, such as management and content update. To address these problems, one alternative is to use Content Management System (CMS), such as WordPress. This project describes the process of migrating a static website to WordPress and adding six additional functionalities according to requirements from a company. In the meantime, theme is used to customize the website based on company’s requirements; specific WordPress plugins and widgets are used to implement additional requirements, including submenus, user registration and login, content update, Facebook and Twitter integration, and RSS support for the new content. Besides, solutions are given to resolve problems, such as the conflict with Internet Explorer (IE) and WordPress security issues. The outcome of this work allows the company to use WordPress to manage the website, to publish automatically new content into online social networking services, to provide customized information to registered users as well as to allow web syndication.Key words: Content Management System, Solution Stack, Static and dynamic website, WordPress

  • 45126.
    Zhuang, Hui
    et al.
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Li, Jintao
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Geng, Weibiao
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Dai, Xiaoming
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Zhang, Zhogshan
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Duplexer design and implementation for self-interference cancellation in full-duplex communications2016Ingår i: European Signal Processing Conference, EUSIPCO 2016, Piscataway, NJ: IEEE Computer Society Digital Library, 2016, 125-129 s., 7760223Konferensbidrag (Refereegranskat)
    Abstract [en]

    The full-duplex (FD) based devices are capable of concurrently transmitting and receiving signals with a single frequency band. However, a severe self-interference (SI) due to the large difference between the power of the devices' own transmission and that of the signal of interest may be imposed on the FD based devices, thus significantly eroding the received signal-to-interference-plus-noise ratio (SINR). To implement the FD devices, the SI power must be sufficiently suppressed to provide a high-enough received SINR for satisfying the decoding requirement. In this paper, the design and implementation of the duplexer for facilitating SI cancellation in FD based devices are investigated, with a new type of duplexer (i.e. an improved directional coupler) designed and verified. It is shown that the SI suppression capability may be up to 36 dB by using the proposed design, which is much higher than that attainable in the commonly designed ferrite circulator

  • 45127.
    Zhufeng, Shao
    Örebro universitet, Handelshögskolan vid Örebro universitet.
    User satisfaction on the application of Mobile-phone wallet in Shanghai Subway station2010Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 45128. Zhusubaliyev, Zhanybai T.
    et al.
    Churilov, Alexander N.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Bifurcation phenomena in an impulsive model of non-basal testosterone regulation2012Ingår i: Chaos, ISSN 1054-1500, E-ISSN 1089-7682, Vol. 22, nr 1, 013121- s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Complex nonlinear dynamics in a recent mathematical model of non-basal testosterone regulation are investigated. In agreement with biological evidence, the pulsatile (non-basal) secretion of testosterone is modeled by frequency and amplitude modulated feedback. It is shown that, in addition to already known periodic motions with one and two pulses in the least period of a closed-loop system solution, cycles of higher periodicity and chaos are present in the model in hand. The broad range of exhibited dynamic behaviors makes the model highly promising in model-based signal processing of hormone data. 

  • 45129.
    Zhyganov, Volodymyr
    Linnéuniversitetet, Fakulteten för teknik (FTK), Institutionen för informatik (IK).
    Achieving and Maintaining IS/IT Alignment in Organizations2013Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The alignment between IS/IT and business is one of the ways to achieve a significant competitive advantage for any organization. It is more important nowadays since any organization can buy any technology in the open market, so technologies themselves don’t give a significant competitive advantage.  Although the concept of the alignment has two decades of the history, it still has a lot of controversial issues and knowledge gaps such as uncertain understanding of the essence of the concept, the complexity of practical implementation and not paying attention to the social dimension of the alignment, i.e. the importance of mutual understanding and collaboration of IT and business executives. The current research aims to investigate the concept of alignment and finds out how an organization can achieve and maintain the IS/IT alignment. Also, this study explores the importance of the social dimension in the alignment concept, clarifies the essence of the IS/IT alignment and investigates how some theoretical concepts can really work in practice. There are many evidences in information systems management literature which describe that strategic alignment is necessary for profit organizations but there are very few which mention that strategic alignment is also important in non-profit academic institutions. During our current research we investigate how this concept works in Linnaeus University and how important it is to achieve and maintain an alignment in any university. In order to achieve the goal of the current research, the relevant information systems management literature was reviewed from a new perspective – a resource-based theory and a unified framework was proposed as a base for the further practical investigation.

    This research is based on a qualitative approach. By using a qualitative approach, we won’t miss anything important and can determine the maximum number of respondents' opinions. The primary data was collected by conducting private semi-structured interviews. The respondents are employees of a big nonprofit organization with the implemented business strategy, IT department and several information systems in use – Linnaeus University. The data were presented and analyzed according to the research questions and presented framework. The current study demonstrates the concept more clearly and tries to reassess the structure of IS/IT alignment. This research provides «a fresh look» at the concept of IS/IT alignment.

  • 45130.
    Zia, Umar
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Enabling Context Awareness in Ambient Environments using Cloud Infrastructures2011Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis was prepared in collaboration with Acreo (Research and Development Company) and OpenCare (IT Company). Its purpose was to design and develop a research testbed to enable context awareness in pervasive environments by modifying the MediaSense framework (EU Funded project) of Mid Sweden University. In ubiquitous environments, the proliferation of devices such as sensors, active badges, mobile phones, RFID and NfC tags enables the development of intelligent services towards new forms of pervasive applications. These intelligent services seamlessly gather context information and the benefits offered are in the provision of better services. The inspiration given by these intelligent services has meant that the focus of thesis has been on using these services in a healthcare application. The challenge is that the proposed testbed should address the intelligent delivery of health information to any host, anywhere, based on the user’s context. Further, context reasoning requires substantial computing power and smart devices have limited resources in terms of processing and memory, so, the testbed should enable smart communication to take place between these devices. The proposed solution satisfies the stated requirements by using a cloud infrastructure and a Distributed Context eXchange Protocol (DCXP). Any device on the internet that is DCXP capable may register with the architecture and share context information in an efficient way. In order to view context information, TV, smartphones, internet tablets and web interfaces have been provided for both the user and the health centre. By successfully addressing the requirements of the testbed, this thesis has enabled the creation of a pervasive healthcare application. Hence, this thesis concludes with the observation that the proposed approach for context awareness in a healthcare system has the ability to deal with the stated challenges. 

  • 45131.
    Ziadi, Ahmed
    KTH, Skolan för datavetenskap och kommunikation (CSC).
    Facebook som komplement till modersmålsundervisning2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Facebook är Sverige mest använda sociala medium. Användaren kan enkelt dela det senaste från sin vardag, sina åsikter samt kommunicera med sina bekanta. Enligt den senaste mätningen från Stiftelsen för internetinfrastruktur, spenderar en tredjedel av unga i åldersgruppen 12-15 år sin internettid på sociala medier, varav 63 % av dem besöker Facebook dagligen.

    I denna studie undersöktes hur Facebook kan användas som komplement till modersmålsundervisningen. Studien utfördes genom en enkätundersökning samt en testgrupp som har kompletterats med semistrukturerade intervjuer.

    Undersökningen gav positiva resultat gentemot användningen av Facebook vid modersmålsundervisningen. Genom användningen av Facebook, kunde elever öva sitt skriv- och diskussionsförmåga utanför klassrummet. Undersökningen visade även att kommunikationen mellan elever och lärare förbättrades genom att eleverna hade möjlighet till lektionsundervisning utanför klassrummet. En annan observation var att elever, som har växt upp i Sverige var mer positiva till användningen av Facebook än sina klasskamrater som har växt upp i andra länder.

  • 45132. Zibuschka, Jan
    et al.
    Fritsch, Lothar
    Norsk Regnesentral.
    A hybrid approach for highly available & secure storage of pseudo-SSO credentials2012Ingår i: Secure IT Systems: 17th Nordic Conference, NordSec 2012, Karlskrona, Sweden, October 31 – November 2, 2012. Proceedings, Springer, 2012, 169-183 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Abstract: We present a novel approach for password/credential storage in Pseudo-SSO scenarios based on a hybrid password hashing/password syncing approach that is directly applicable to the contemporary Web. The approach supports passwords without requiring modification of the server side and thus is immediately useful; however, it may still prove useful for storing more advanced credentials in future SSO and identity management scenarios, and offers a high level of security. Keywords. Single sign-on, authentication, syncing, hashing.

  • 45133.
    Zibuschka, Jan
    et al.
    Goethe University.
    Fritsch, Lothar
    Goethe University.
    Radmacher, Mike
    Goethe University.
    Scherner, Tobias
    Goethe University.
    Rannenberg, Kai
    Goethe University.
    Enabling privacy of real-life LBS: A platform for flexible mobile service provisioning2007Ingår i: New Approaches for Security, Privacy and Trust in Complex Environments, Springer, 2007, 325-336 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    Privacy in computerized environments is perceived very differently depending on the respective point of view. Often "privacy enhancing technologies" - initiated by the user, as a measure of self-defense - are seen as conflicting with business goals such as cost-efficiency, revenue assurance, and options for further business development based on existing data. This paper presents the design and implementation of an architecture and prototype for privacy-friendly, interoperable location-based services (LBS), based on intermediation of location data via a location middleware component. The aim is to combine privacy-friendliness, efficiency, and market potential. Therefore the security interests of the stakeholders are analyzed and an architecture solution including an intermediary is introduced. Then the prototype implementation (at a mobile operator) is described and the usage of the prototype for a commercial service and product offer by the operator involved in the development is discussed.

  • 45134.
    Zichner, Thomas
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Building graph models of oncogenesis by using microRNA expression data2008Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats
    Abstract [en]

    MicroRNAs (miRNAs) are a class of small non-coding RNAs that control gene expression by targeting mRNAs and triggering either translation repression or RNA degradation. Several groups pointed out that miRNAs play a major role in several diseases, including cancer. This is assumed since the expression level of several miRNAs differs between normal and cancerous cells. Further, it has been shown that miRNAs are involved in cell proliferation and cell death.

    Because of this role it is suspected that miRNAs could serve as biomarkers to improve tumor classification, therapy selection, or prediction of survival. In this context, it is questioned, among other things, whether miRNA deregulations in cancer cells occur according to some pattern or in a rather random order. With this work we contribute to answering this question by adapting two approaches (Beerenwinkel et al. (J Comput Biol, 2005) and Höglund et al. (Gene Chromosome Canc, 2001)), developed to derive graph models of oncogenesis for chromosomal imbalances, to miRNA expression data and applying them to a breast cancer data set. Further, we evaluated the results by comparing them to results derived from randomly altered versions of the used data set.

    We could show that miRNA deregulations most likely follow a rough temporal order, i.e. some deregulations occur early and some occur late in cancer progression. Thus, it seems to be possible that the expression level of some miRNAs can be used as indicator for the stage of a tumor. Further, our results suggest that the over expression of mir-21 as well as mir-102 are initial events in breast cancer oncogenesis.

    Additionally, we identified a set of miRNAs showing a cluster-like behavior, i.e. their deregulations often occur together in a tumor, but other deregulations are less frequently present. These miRNAs are let-7d, mir-10b, mir-125a, mir-125b, mir-145, mir-206, and mir-210.

    Further, we could confirm the strong relationship between the expression of mir-125a and mir-125b.

  • 45135.
    Zieba, Maciej
    Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation.
    Multistage neural networks for pattern recognition2009Självständigt arbete på avancerad nivå (masterexamen)Studentuppsats (Examensarbete)
    Abstract [en]

    In this work the concept of multistage neural networks is going to be presented. The possibility of using this type of structure for pattern recognition would be discussed and examined with chosen problem from eld area. The results of experiment would be confront with other possible methods used for the problem.

  • 45136. Ziegler, Andreas
    et al.
    Repsilber, Dirk
    Data rotation for efficient comparative genomics2004Konferensbidrag (Refereegranskat)
  • 45137.
    Ziegler, Gernot
    Linköpings universitet, Institutionen för teknik och naturvetenskap.
    MPEG Z/Alpha and high-resolution MPEG2003Självständigt arbete på grundnivå (yrkesexamen)Studentuppsats
    Abstract [en]

    The progression of technical development has yielded practicable camera systems for the acquisition of so called depth maps, images with depth information.

    Images and movies with depth information open the door for new types of applications in the area of computer graphics and vision. That implies that they will need to be processed in all increasing volumes.

    Increased depth image processing puts forth the demand for a standardized data format for the exchange of image data with depth information, both still and animated. Software to convert acquired depth data to such videoformats is highly necessary.

    This diploma thesis sheds light on many of the issues that come with this new task group. It spans from data acquisition over readily available software for the data encoding to possible future applications.

    Further, a software architecture fulfilling all of the mentioned demands is presented.

    The encoder is comprised of a collection of UNIX programs that generate MPEG Z/Alpha, an MPEG2 based video format. MPEG Z/Alpha contains beside MPEG2's standard data streams one extra data stream to store image depth information (and transparency).

    The decoder suite, called TexMPEG, is a C library for the in-memory decompression of MPEG Z/Alpha. Much effort has been put into video decoder parallelization, and TexMPEG is now capable of decoding multiple video streams, not only in parallel internally, but also with inherent frame synchronization between parallely decoded MPEG videos.

  • 45138.
    Zielinski, Antoni
    Högskolan Dalarna, Akademin Humaniora och medier, Bildproduktion.
    Filmklipparens arbetsprocess i Hollywood och Europa: Undersökning av möjliga skillnader och likheter i filmklipparens arbetsprocess i Hollywood och Europa2016Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Arbetsprocessen har förändrats under filmhistoriens gång, delvis på grund av teknologiska framsteg, som till exempel bytet till digitala filmklippningsverktyg. Hur filmklippningsprocessen ser ut, skiljer sig mellan filmklippare, men kan man även finna skillnader mellan olika regioner?

    Den här uppsatsen undersöker ifall det finns några likheter och skillnader mellan arbetsprocessen för filmklippning i Europa och Hollywood. Undersökningen genomförs genom en kvalitativ analys, där material samlas in från diverse påståenden från filmklippare i litteratur, samt från kvalitativa intervjuer som genomförs med filmklipparna Martin Hunter och Michal Leszczylowski.

    Resultatet pekar på att det finns både likheter och skillnader mellan de två regionerna. De båda regionernas arbetsprocess har påverkats av bytet till digital filmklippning. Deras arbetsuppgifter liknar på många sätt varandra, med det skiljer sig hur dessa arbetsuppgifter utförs. I Hollywood kan det ofta skådas mer resurser tillgängliga för filmklipparen, men samtidigt också mer inflytande från producenter och filmstudior på deras arbete. Däremot har filmklipparen i Europa ett starkare samarbete med regissören, och enligt dem är deras huvudsakliga uppgift att arbeta fram regissörens vision av filmen.

  • 45139.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Adaptive Behavior in Autonomous Agents1998Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper gives an overview of the bottom-up approach to artificial intelligence (AI), commonly referred to as behavior-oriented AI. The behavior-oriented approach, with its focus on the interaction between autonomous agents and their environments, is introduced by contrasting it with the traditional approach of knowledge-based AI. Different notions of autonomy are discussed, and key problems of generating adaptive and complex behavior are identified. A number of techniques for the generation of behavior are introduced and evaluated regarding their potential for realizing different aspects of autonomy as well as adaptivity and complexity of behavior. It is concluded that in order to realize truly autonomous and intelligent agents, the behavior-oriented approach will have to focus even more on life-like qualities in both agents and environments.

  • 45140.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Cybernetics and embodied cognition: on the construction of realities in organisms and robots.2005Ingår i: Kybernetes, ISSN 0368-492X, Vol. 34, nr 1-2, 118-128 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Abstract: Purpose – To point out the relevance of Heinz von Foerster's work to modern embodied cognitive science and artifical intelligence research.

    Design/methodology/approach – The paper discusses (a) von Foerster's contributions to understanding the limitations of the computer metaphor which has long dominated cognitive science, and (b) his theories concerning how reality is constructed in organizationally closed organisms, and what the underlying neural mechanisms are. The latter is exemplified with a simple neuro-robotic model that illustrates the constructive and anticipatory nature of memory.

    Findings – von Foerster's work on the integration of a radical constructivest philosophy of knowledge construction with models of the underlying neurophysiological and sensorimotor mechanisms is still highly relevant to the understanding of embodied cognition and robotic models thereof.

    Originality/value – This paper identifies conceptual contributions that von Foerster's constructivist cybernetics can make to cognitive science's still limited understanding of the embodiment of cognition and “representation”.

  • 45141.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    From Rats to Cognitive robots: Biological insipiration in cognitive systems research2009Ingår i: Public Service Review: European Union, ISSN 1472-3395, nr 18, 330-331 s.Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 45142.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    From Rats to Robots2009Ingår i: The Parliament Magazine, ISSN 1372-7966, nr 292, 62- s.Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 45143.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information. Högskolan i Skövde, Forskningscentrum för Informationsteknologi.
    On the role of emotion in biological and robotic autonomy2008Ingår i: Biosystems (Amsterdam. Print), ISSN 0303-2647, E-ISSN 1872-8324, Vol. 91, nr 2, 401-408 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper reviews some of the differences between notions of biological and robotic autonomy, and how these differences have been reflected in discussions of embodiment, grounding and other concepts in AI and autonomous robotics. Furthermore, the relations between homeostasis, emotion and embodied cognition are discussed as well as recent proposals to model their interplay in robots, which reflects a commitment to a multi-tiered affectively/emotionally embodied view of mind that takes organismic embodiment more serious than usually done in biologically inspired robotics.

  • 45144.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Radar Image Segmentation using Recurrent Artificial Neural Networks1996Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper discusses the application of artificial neural networks to the segmentation of Doppler radar images, in particular the detection of oil spills within sea environments, based on a classification of radar backscatter signals. Best results have been achieved with recurrent backpropagation networks of an architecture similar to that of Elman's Simple Recurrent Network. The recurrent networks are shown to be very robust to variations in both sea state (weather conditions) as well as illumination distance, and their performance is analysed in further detail.

  • 45145.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Radar Image Segmentation using Second-Order Recurrent Networks1996Rapport (Övrigt vetenskapligt)
    Abstract [en]

    A second-order recurrent artificial neural network architecture for the segmentation and integration of radar images is introduced in this paper. This architecture consists of two sub-networks: a function network that classifies radar measurements into four different categories of objects in sea environments (water, oil spills, land and boats), and a context network that dynamically computes the function network's input weights. It is shown that this mechanism allows networks to learn to solve the task through a dynamic adaptation of their weighting of different radar measurements.behaviour.

  • 45146.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Radar Image Segmentation using Self-Adapting Recurrent Networks1997Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper presents a novel approach to the segmentation and integration of (radar) images using a second-order recurrent artificial neural network architecture consisting of two sub- networks: a function network that classifies radar measurements into four different categories of objects in sea environments (water, oil spills, land and boats), and a context network that dynamically computes the function network's input weights. It is shown that in experiments (using simulated radar images) this mechanism outperforms conventional artificial neural networks since it allows the network to learn to solve the task through a dynamic adaptation of its classification function based on its internal state closely reflecting the current context.

  • 45147.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Recurrent Artficial Neural Networks for the Detection of Oil Spills from Doppler Radar Imagery1995Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper discusses the application of artificial neural networks (ANNs) to the detection of oil spills in sea clutter environments from the classification of radar backscatter signals. A comparison and evaluation of different network architectures regarding reliability of dection and robustness to varying sea states/wind conditions shows that for this problem best results are achieved with a recurrent architecture similar to that of Elman's SRN.

  • 45148.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Remembering how to behave: Recurrent neural networks for adaptive robot behavior.1999Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This paper discusses the use of recurrent neural networks for control of and learning in robots and autonomous agents. In particular the use of feedback in both first- and higher-order recurrent network architectures for the realization of adaptive robot behavior is investigated. Two experiments, in which controller network weights are evolved to solve tasks requiring robots to exhibit context- or state-dependent behavior, are used to demonstrate and analyze different recurrent control architectures.

  • 45149.
    Ziemke, Tom
    Högskolan i Skövde, Institutionen för kommunikation och information.
    Rethinking Grounding1999Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The grounding problem is, generally speaking, the problem of causally connecting an artificial agent with its environment such that the agent's (internal) mechanisms and behaviour can be intrinsic and meaningful to itself, rather than dependent on an external designer or observer. This paper briefly reviews Searle's and Harnad's analyses of the grounding problem are and evaluates cognitivist and enactivist approaches to solving it. It is argued that, although the two categories of grounding approaches differ in their nature and the problems they have to face, both, so far, fail to provide fully grounded systems. Further it is argued here that the reason the problem is somewhat underestimated lies in the notions of situatedness and embodiment in modern AI, which goes beyond purely computational systems, but fails to acknowledge the historically grounded nature of the relation between living systems and their environments.

  • 45150.
    Ziemke, Tom
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system. Linköpings universitet, Tekniska fakulteten. Interaction Lab, School of Informatics, University of Skövde, Skövde, Swede.
    The body of knowledge: On the role of the living body in grounding embodied cognition2016Ingår i: Biosystems (Amsterdam. Print), ISSN 0303-2647, E-ISSN 1872-8324, Vol. 148, 4-11 s.Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Embodied cognition is a hot topic in both cognitive science and AI, despite the fact that there still is relatively little consensus regarding what exactly constitutes ‘embodiment’. While most embodied AI and cognitive robotics research views the body as the physical/sensorimotor interface that allows to ground computational cognitive processes in sensorimotor interactions with the environment, more biologically-based notions of embodied cognition emphasize the fundamental role that the living body – and more specifically its homeostatic/allostatic self-regulation – plays in grounding both sensorimotor interactions and embodied cognitive processes. Adopting the latter position – a multi-tiered affectively embodied view of cognition in living systems – it is further argued that modeling organisms as layered networks of bodily self-regulation mechanisms can make significant contributions to our scientific understanding of embodied cognition.

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