Change search
Refine search result
3456789 251 - 300 of 2518
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 251.
    Bergkvist, Markus
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Olandersson, Tobias
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Machine learning in simulated RoboCup2003Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    An implementation of the Electric Field Approach applied to the simulated RoboCup is presented, together with a demonstration of a learning system. Results are presented from the optimization of the Electric Field parameters in a limited situation, using the learning system. Learning techniques used in contemporary RoboCup research are also described including a brief presentation of their results.

  • 252. Berglund, Anders
    et al.
    Börstler, Jürgen
    Umeå universitet, Institutionen för datavetenskap.
    Dagiéne, Valentina
    Forword to the Special Section on the ECOOP'06 Workshop on Pedagogies and Tools for the Teaching and Learning of Object-Oriented Concepts2007In: Informatics in Education, Vol. 6, no 1, p. 3-4Article in journal (Other academic)
  • 253.
    Bergman, Carolina
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Wilhelmsson, Ann
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Datavetenskapliga/datatekniska högre utbildningar riktade till kvinnor: Ett framgångsrikt koncept?2002Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Siffror om könsfördelning inom IT-branschen och på högre tekniska utbildningar talar sitt tydliga språk. Andelen män inom ämnesområdena data och teknik är ofta betydligt större än andelen kvinnor. Detta kan ge till följd att samhället går miste om en stor del potentiella begåvningar. En jämnare könsfördelning brukar dessutom resultera i ett trevligare och gemytligare klimat. För att öka intresset bland kvinnliga studenter för vissa IT-utbildningar har en del universitet och högskolor ändrat utbildningsformer och innehåll. Några har även utformat särskilda program som vänder sig till kvinnor. Vi har i vårt kandidatarbete inriktat oss på tre utbildningar av den karaktären: Datateknisk utbildning för kvinnor (DUK), Datavetenskapligt program företrädesvis för kvinnor (DUR) och Datateknisk ingång för kvinnor (DTI). De viktigaste frågeställningarna som vi kommer att besvara och de slutsatser som vi har fått fram i rapporten är: Frågeställningar: Ø Finns det idag ett behov av högre tekniska utbildningar som är riktade till kvinnor? Ø Har kvinnor behov av en speciell pedagogik i högre tekniska utbildningar och vad är i så fall innebörden av den? Ø Ska man ha undervisning i klass med bara kvinnor hela utbildningen, eller är en senare integrering med program som är öppna för båda könen att föredra? Slutsatser: Ø I dagens samhälle finns det ett behov av högre tekniska utbildningar som bara är riktade till kvinnor. Ø Att studera i en kvinnlig klass resulterar i en pedagogik som anses vara av stor betydelse Ø Vikten av en integrering med andra mixade program någon gång under utbildningstiden är stor.

  • 254.
    Bergman Martinkauppi, Louise
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science.
    He, Qiuping
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science.
    Performance Evaluation and Comparison of Standard Cryptographic Algorithms and Chinese Cryptographic Algorithms2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background. China is regulating the import, export, sale, and use of encryption technology in China. If any foreign company wants to develop or release a product in China, they need to report their use of any encryption technology to the Office of State Commercial Cryptography Administration (OSCCA) to gain approval. SM2, SM3, and SM4 are cryptographic standards published by OSCCA and are authorized to be used in China. To comply with Chinese cryptography laws organizations and companies may have to replace standard cryptographic algorithms in their systems with Chinese cryptographic algorithms, such as SM2, SM3, and SM4. It is important to know beforehand how the replacement of algorithms will impact performance to determine future system costs. Objectives. Perform a theoretical study and performance comparison of the standard cryptographic algorithms and Chinese Cryptographic algorithms. The standard cryptographic algorithms studied are RSA, ECDSA, SHA-256, and AES-128, and the Chinese cryptographic algorithms studied are SM2, SM3, and SM4. Methods. A literature analysis was conducted to gain knowledge and collect information about the selected cryptographic algorithms in order to make a theoretical comparison of the algorithms. An experiment was conducted to get measurements of how the algorithms perform and to be able to rate them. Results. The literature analysis provides a comparison that identifies design similarities and differences between the algorithms. The controlled experiment provides measurements of the metrics of the algorithms mentioned in objectives. Conclusions. The conclusions are that the digital signature algorithms SM2 and ECDSA have similar design and also similar performance. SM2 and RSA have fundamentally different designs, and SM2 performs better than RSA when generating keys and signatures. When verifying signatures, RSA shows comparable performance in some cases and worse performance in other cases. Hash algorithms SM3 and SHA-256 have many design similarities, but SHA-256 performs slightly better than SM3. AES-128 and SM4 have many similarities but also a few differences. In the controlled experiment, AES-128 outperforms SM4 with a significant margin.

  • 255.
    Bergsten, John
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Öhman, Konrad
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Player Analysis in Computer Games Using Artificial Neural Networks2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Star Vault AB is a video game development company that has developed the video game Mortal Online. The company has stated that they believe that players new to the game repeatedly find themselves being lost in the game. The objective of this study is to evaluate whether or not an Artificial Neural Network can be used to evaluate when a player is lost in the game Mortal Online. This is done using the free open source library Fast Artifical Neural Network Library. People are invited to a data collection event where they play a tweaked version of the game to facilitate data collection. Players specify whether they are lost or not and the data collected is flagged accordingly. The collected data is then prepared with different parameters to be used when training multiple Artificial Neural Networks. When creating an Artificial Neural Network there exists several parameters which have an impact on its performance. Performance is defined as the balance of high prediction accuracy against low false positive rate. These parameters vary depending on the purpose of the Artificial Neural Network. A quantitative approach is followed where these parameters are varied to investigate which values result in the Artificial Neural Network which best identifies when a player is lost. The parameters are grouped into stages where all combinations of parameter values within each stage are evaluated to reduce the amount of Artificial Neural Networks which have to be trained, with the best performing parameters of each stage being used in subsequent stages. The result is a set of values for the parameters that are considered as ideal as possible. These parameter values are then altered one at a time to verify that they are ideal. The results show that a set of parameters exist which can optimize the Artificial Neural Network model to identify when a player is lost, however not with the high performance that was hoped for. It is theorized that the ambiguity of the word "lost" and the complexity of the game are critical to the low performance.

  • 256.
    Berner, Jessica
    et al.
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Rennemark, Mikael
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Jogreus, Claes
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mathematics and Natural Sciences.
    Anderberg, Peter
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Sköldunger, Anders
    Wahlberg, Maria
    Elmståhl, Sölve
    Berglund, Johan
    Blekinge Institute of Technology, Faculty of Health Sciences, Department of Health.
    Factors influencing Internet usage in older adults (65 years and above) living in rural and urban Sweden2015In: Health Informatics Journal, ISSN 1460-4582, E-ISSN 1741-2811, Vol. 21, no 3, p. 237-249Article in journal (Refereed)
    Abstract [en]

    Older adults living in rural and urban areas have shown to distinguish themselves in technology adoption; a clearer profile of their Internet use is important in order to provide better technological and health-care solutions. Older adults' Internet use was investigated across large to midsize cities and rural Sweden. The sample consisted of 7181 older adults ranging from 59 to 100 years old. Internet use was investigated with age, education, gender, household economy, cognition, living alone/or with someone and rural/urban living. Logistic regression was used. Those living in rural areas used the Internet less than their urban counterparts. Being younger and higher educated influenced Internet use; for older urban adults, these factors as well as living with someone and having good cognitive functioning were influential. Solutions are needed to avoid the exclusion of some older adults by a society that is today being shaped by the Internet.

  • 257.
    Berner, Jessica
    et al.
    Blekinge Institute of Technology, School of Health Science.
    Rennemark, Mikael
    Blekinge Institute of Technology, School of Health Science.
    Jogréus, Claes
    Blekinge Institute of Technology, School of Engineering, Department of Mathematics and Natural Sciences.
    Berglund, Johan
    Blekinge Institute of Technology, School of Health Science.
    Distribution of personality, individual characteristics and internet usage in Swedish older adults2012In: Aging and Mental Health, ISSN 1360-7863 , Vol. 16, no 1, p. 119-126Article in journal (Refereed)
    Abstract [en]

    Objectives: This paper investigated factors associated with internet usage in the Swedish older adults ranging in age from 60 to 96. Personality traits and individual characteristics have been previously noted to influence internet usage, where older adults have not been the focus population. In this study the relationships between personality, individual characteristics and internet usage were investigated. Methods: A descriptive analysis of the personality tests of a total of 1402 subjects included in the Swedish National Study on Aging and Care (SNAC) was conducted. Three variables were controlled for: sex, age and education. Descriptive statistics, Mann-Whitney and Kruskal-Wallis tests, chi square tests and a logistic regression were used in order to detect the relationships with internet usage. Results: Men differ significantly from women in the personality traits analysis. Those with higher education were more open and neuroticism was lower in the oldest older adults. Internet usage declined significantly with age and those with middle to higher education were using the internet the most. No other associations with internet use were found Conclusion: Personality traits and individual characteristics do not seem to influence the Swedish older adult and their internet usage. What one needs to account for is the age and education of the person. The more educated and the youngest cohorts were using the internet more frequently.

  • 258.
    Berntsson, Fredrik
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Schengensamarbetet – Europas dröm2014Student thesis
    Abstract [sv]

    Denna uppsats klargör vad Schengensamarbetet är för något, varför det finns och hur det fungerar. Uppsatsen går igenom alla delar av samarbetet som till synes största del består av att avskaffa personkontrollerna mellan medlemsländerna.

  • 259. Bertilsson, Emil
    Dynamic Creation of Multi-resolution Triangulated Irregular Network2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Context. Triangulated irregular network (TIN) can produce terrain meshes with a reduced triangle count compared to a regular grid. At the same time, TIN meshes are more challenging to optimize in real-time in comparison to other approaches.

    Objectives. This thesis explores efficient generation of view-dependent, adaptive TIN meshes for terrain during runtime with no or minimal preprocessing.

    Methods. Since the workings of the proposed technique is a novel approach, an empirical strategy was employed to present the findings instead of partial comparisons to related techniques.

    Results. To determine the result of the technique, run-time performance is measured and presented to provide incentives for implementation and improvements on the proposed algorithm. Several problem sizes are tested with varying terrain features to determine the effectiveness as a result of the features in the mesh. 

    Conclusions. We conclude that reducing the problem of mesh simplification to that of 2D Delaunay triangulation on sampled points spanning terrains is valid approach for triangulating on-the-fly. Moreover, this approach opens up for further improvements which may soon allow real-time triangulation of TINs.

  • 260.
    Bertilsson, Emil
    et al.
    Blekinge Institute of Technology.
    Goswami, Prashant
    Blekinge Institute of Technology.
    Dynamic Creation of Multi-resolution Triangulated Irregular Network2016In: Proceedings of SIGRAD 2016 / [ed] M. Hayashi, 2016Conference paper (Refereed)
    Abstract [en]

    Triangulated irregular network (TIN) can produce terrain meshes with a reduced triangle count compared toregular grid. At the same time, TIN meshes are more challenging to optimize in real-time in comparison to otherapproaches. This paper explores efficient generation of view-dependent, adaptive TIN meshes for terrain duringruntime with no or minimal preprocessing. This is achieved by reducing the problem of mesh simplification to thatof inexpensive 2D Delaunay triangulation and lifting it back to 3D. The approach and its efficiency is validatedwith suitable datasets.

  • 261.
    Bertilsson, Tobias
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Telecommunication Systems.
    Persson, Mårten
    Blekinge Institute of Technology, School of Engineering, Department of Telecommunication Systems.
    Situation-dependent spontaneous mobile information service for travelers2006Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    This application is created to provide valid and relevant travel information to travelers on their journey. The application is proposed as a demonstration for seamless communications in the VINNOVA-sponsored project PIITSA (Personal Information Intelligent Transport systems through Seamless communications and Autonomous decisions). The PIITSA-project is a cooperation between Blekinge Institute of Technology (BTH), Saab AB, SP Swedish National Testing and Research Institute and Swedish Road Administration region Stockholm. The project is going on under three years, and the goal is to define communication and decision functions which will make it easier for ITS-applications (Intelligent Transport Systems and Services) that have the need of supplying personalised information. This project presents a solution to the question “How do I get from point A to point B in any case”. All that the user needs is a PDA with the application installed and being able to connect to the service via a mobile network. If the user has specified a route in the application, then the user will receive up-to-date information on how to get to his destination. This information is presented on the user’s PDA. If something happens on the current route, then the user will get an automatic message sent to him presenting the problem and give him a new travel route. Thanks to this the user won’t be stuck in the traffic problem and will probably reach its destination in time.

  • 262.
    Bertoni, Alessandro
    et al.
    Blekinge Institute of Technology, Faculty of Engineering, Department of Mechanical Engineering. Blekinge Institute of Technology.
    Hallstedt, Sophie
    Blekinge Institute of Technology, Faculty of Engineering, Department of Strategic Sustainable Development. Blekinge Institute of Technology.
    Dasari, Siva Krishna
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science. Blekinge Institute of Technology.
    Andersson, Petter
    GKN Aerospace Engine Systems, SWE.
    Integration of Value and Sustainability Assessment in Design Space Exploration by Machine Learning: An Aerospace Application2019In: Design ScienceArticle in journal (Refereed)
  • 263. Bertoni, Marco
    et al.
    Larsson, Andreas
    Ericson, Åsa
    Chirumalla, Koteshwar
    Larsson, Tobias
    Blekinge Institute of Technology, School of Engineering, Department of Mechanical Engineering.
    Isaksson, Ola
    Randall, Dave
    The rise of social product development2012In: International Journal of Networking and Virtual Organisations, ISSN 1470-9503, Vol. 11, no 2, p. 188-207Article in journal (Refereed)
    Abstract [en]

    The aim of the paper is to discuss the rising potential of social software to increase the knowledge management capabilities of virtual product development teams. It presents six fundamental transitions, elaborated from the empirical findings, which justify the rise of a more bottom-up, social creation and sharing of engineering knowledge in the virtual organisation. The study suggests that traditional engineering knowledge management approaches alone are not sufficient to support development activities in the virtual organisation, and that such teams display an increasing demand for social, comparatively lightweight and remixable platforms for bottom-up, social creation and sharing of knowledge.

  • 264.
    Bethalam, Anil Varma
    et al.
    Blekinge Institute of Technology, School of Computing.
    Amburu, Prasanna Kumar
    Blekinge Institute of Technology, School of Computing.
    Causes of TCP Reset in Mobile Web Browsing2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Web browsing has been one of the most popular activities on the internet. The increasing importance of the Web in everyday life calls for device-independent access to existing web sites. Although, there is full Web access available on mobile phones the user experience is often poor when compared to the Web user experience on Personal Computer (PC). Therfore, it is important for the Internet service provider to find the indications of user dissatisfaction from the network. While using the mobile Web, user can normally abort the transfer by pressing the stop or reset buttons in the browsers, leaving the page being downloaded by following a bookmark or can close the connection. Such events can be observed through the TCP reset (RST) flag from traffic on network level. In this thesis we have investigated the possible causes of TCP RST flags mobile Web session is interrupted. We further analyze up to what extent we can rely on TCP RST flags for being an indication of user dissatisfaction in mobile web browsing. Therefore, an experiment testbed is developed to capture the TCP packet traces during controlled active tests. Results are gathered using mobile devices with four popular mobile operating systems (OS). The trace files captured are analyzed using perl script to dicern the flow and focusing on the TCP RST flag during the flow. Further, TSTAT tool is used to validate our trace files.

  • 265.
    Betschart, Willie
    Blekinge Institute of Technology, School of Engineering, Department of Signal Processing.
    Applying intelligent statistical methods on biometric systems2005Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    This master’s thesis work was performed at Optimum Biometric Labs, OBL, located in Karlskrona, Sweden. Optimum Biometric Labs perform independent scenario evaluations to companies who develop biometric devices. The company has a product Optimum preConTM which is surveillance and diagnosis tool for biometric systems. This thesis work’s objective was to develop a conceptual model and implement it as an additional layer above the biometric layer with intelligence about the biometric users. The layer is influenced by the general procedure of biometrics in a multimodal behavioural way. It is working in an unsupervised way and performs in an unsupervised manner. While biometric systems are increasingly adopted the technologies have some inherent problems such as false match and false non-match. In practice, a rejected user can not be interpreted as an impostor since the user simply might have problems using his/her biometric feature. The proposed methods in this project are dealing with these problems when analysing biometric usage in runtime. Another fact which may give rise to false rejections is template aging; a phenomenon where the enrolled user’s template is too old compared towards the user’s current biometric feature. A theoretical approach of template aging was known; however since the analysis of template aging detection was correlated with potential system flaws such as device defects or human generated risks such as impostor attacks this task would become difficult to solve in an unsupervised system but when ignoring the definition of template aging, the detection of similar effects was possible. One of the objectives of this project was to detect template aging in a predictive sense; this task failed to be carried out because the absence of basis performing this kind of tasks. The developed program performs abnormality detection at each incoming event from a biometric system. Each verification attempt is assumed to be from a genuine user unless any deviation according to the user's history is found, an abnormality. The possibility of an impostor attack depends on the degree of the abnormality. The application makes relative decisions between fraud possibilities or if genuine user was the source of what caused the deviations. This is presented as an alarm with the degree of impostor possibility. This intelligent layer has increased Optimum preCon´s capacity as a surveillance tool for biometrics. This product is an efficient complement to biometric systems in a steady up-going worldwide market.

  • 266. Beyene, Ayne A.
    et al.
    Welemariam, Tewelle
    Persson, Marie
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Lavesson, Niklas
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Improved concept drift handling in surgery prediction and other applications2015In: Knowledge and Information Systems, ISSN 0219-1377, Vol. 44, no 1, p. 177-196Article in journal (Refereed)
    Abstract [en]

    The article presents a new algorithm for handling concept drift: the Trigger-based Ensemble (TBE) is designed to handle concept drift in surgery prediction but it is shown to perform well for other classification problems as well. At the primary care, queries about the need for surgical treatment are referred to a surgeon specialist. At the secondary care, referrals are reviewed by a team of specialists. The possible outcomes of this review are that the referral: (i) is canceled, (ii) needs to be complemented, or (iii) is predicted to lead to surgery. In the third case, the referred patient is scheduled for an appointment with a surgeon specialist. This article focuses on the binary prediction of case three (surgery prediction). The guidelines for the referral and the review of the referral are changed due to, e.g., scientific developments and clinical practices. Existing decision support is based on the expert systems approach, which usually requires manual updates when changes in clinical practice occur. In order to automatically revise decision rules, the occurrence of concept drift (CD) must be detected and handled. The existing CD handling techniques are often specialized; it is challenging to develop a more generic technique that performs well regardless of CD type. Experiments are conducted to measure the impact of CD on prediction performance and to reduce CD impact. The experiments evaluate and compare TBE to three existing CD handling methods (AWE, Active Classifier, and Learn++) on one real-world dataset and one artificial dataset. TBA significantly outperforms the other algorithms on both datasets but is less accurate on noisy synthetic variations of the real-world dataset.

  • 267.
    Beyene, Ayne
    et al.
    Blekinge Institute of Technology, School of Computing.
    Welemariam, Tewelle
    Blekinge Institute of Technology, School of Computing.
    Concept Drift in Surgery Prediction2012Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Context: In healthcare, the decision of patient referral evolves through time because of changes in scientific developments, and clinical practices. Existing decision support systems of patient referral are based on the expert systems approach. This usually requires manual updates when changes in clinical practices occur. Automatically updating the decision support system by identifying and handling so-called concept drift improves the efficiency of healthcare systems. In the stateof-the- art, there are only specific ways of handling concept drift; developing a more generic technique which works regardless of restrictions on how slow, fast, sudden, gradual, local, global, cyclical, noisy or otherwise changes in internal distribution, is still a challenge. Objectives: An algorithm that handles concept drift in surgery prediction is investigated. Concept drift detection techniques are evaluated to find out a suitable detection technique in the context of surgery prediction. Moreover, a plausible combination of detection and handling algorithms including the proposed algorithm, Trigger Based Ensemble (TBE)+, are evaluated on hospital data. Method: Experiments are conducted to investigates the impact of concept drift on prediction performance and to reduce concept drift impact. The experiments compare three existing methods (AWE, Active Classifier, Learn++) and the proposed algorithm, Trigger Based Ensemble(TBE). Real-world dataset from orthopedics department of Belkinge hospital and other domain dataset are used in the experiment. Results: The negative impact of concept drift in surgery prediction is investigated. The relationship between temporal changes in data distribution and surgery prediction concept drift is identified. Furthermore, the proposed algorithm is evaluated and compared with existing handling approaches. Conclusion: The proposed algorithm, Trigger Based Ensemble (TBE), is capable of detecting the occurrences of concept drifts and to adapt quickly to various changes. The Trigger Based Ensemble algorithm performed comparatively better or sometimes similar to the existing concept drift handling algorithms in the absence of noise. Moreover, the performance of Trigger Based Ensemble is consistent for small and large dataset. The research is of twofold contributions, in that it is improving surgery prediction performance as well as contributing one competitive concept drift handling algorithm to the area of computer science.

  • 268.
    Beygo, Ömer Kerem
    et al.
    Blekinge Institute of Technology, School of Computing.
    Eraslan, Cihan
    Blekinge Institute of Technology, School of Computing.
    Enhancing Security and Usability Features of NFC2009Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Near Field Communication (NFC) is a short range wireless communication protocol which is primarily intended to be used on mobile phones. Building upon existing infrastructure of RFID, NFC brings simplicity for connection of mobile devices, service initiation, mobile payment and ticketing. However, NFC still remains as a field that number of researches done are limited. The aim of this paper was to provide solutions for the problems of NFC that cause security risks and hurt user experience. To reach this goal we have reviewed the current literature and implemented an NFC application that we have used throughout our user experience tests. This application provides a practical way to store and transfer contact information using NFC. The results of the study indicated that usability and security suffer from lack of user awareness and physical design of the mobile phones.

  • 269. Bhattacharyya, Prantik
    et al.
    Rowe, Jeff
    Wu, Felix
    Haigh, Karen
    Lavesson, Niklas
    Johnson, Henric
    Your Best might not be Good enough: Ranking in Collaborative Social Search Engines2011Conference paper (Refereed)
    Abstract [en]

    A relevant feature of online social networks like Facebook is the scope for users to share external information from the web with their friends by sharing an URL. The phenomenon of sharing has bridged the web graph with the social network graph and the shared knowledge in ego networks has become a source for relevant information for an individual user, leading to the emergence of social search as a powerful tool for information retrieval. Consideration of the social context has become an essential factor in the process of ranking results in response to queries in social search engines. In this work, we present InfoSearch, a social search engine built over the Facebook platform, which lets users search for information based on what their friends have shared. We identify and implement three distinct ranking factors based on the number of mutual friends, social group membership, and time stamp of shared documents to rank results for user searches. We perform user studies based on the Facebook feeds of two authors to understand the impact of each ranking factor on the result for two queries.

  • 270. Bhole, Yogesh
    et al.
    Popescu, Adrian
    Measurement and Analysis of HTTP Traffic2005In: Journal of Network and Systems Management, ISSN 1064-7570, E-ISSN 1573-7705, Vol. 13, no 4, p. 357-371Article in journal (Refereed)
    Abstract [en]

    The usage of Internet is rapidly increasing and a large part of the Internet traffic is generated by the World Wide Web (WWW) and the associated protocol HiperText Transfer Protocol (HTTP). Several important parameters that affect the performance of the WWW are bandwidth, scalability and latency. To tackle these parameters and to improve the overall performance of the system, it is important to understand and to characterize the application level characteristics. This article is reporting on the measurement and analysis of HTTP traffic collected on the student access network at the Blekinge Institute of Technology in Karlskrona, Sweden. The analysis is done on various HTTP traffic parameters, e.g., inter-session timings, inter-arrival timings, request message sizes, response code and number of transactions. The reported results can be useful for building synthetic workloads for simulation and benchmarking purposes.

  • 271.
    Bhutto, Tarique Inayat
    Blekinge Institute of Technology, School of Engineering.
    Root LDPC Codes for Non Ergodic Transmission Channels2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    4 ABSTRACT Tremendous amount of research has been conducted in modern coding theory in the past few years and much of the work has been done in developing new coding techniques. Low density parity check (LDPC) codes are class of linear block error correcting codes which provide capacity performance on a large collection of data transmission and storage channels while Root LDPC codes in this thesis work are admitting implementable decoders with manageable complexity. Furthermore, work has been conducted to develop graphical methods to represent LDPC codes. This thesis implement one of the LDPC kind “Root LDPC code” using iterative method and calculate its threshold level for binary and non-binary Root LDPC code. This threshold value can serve as a starting point for further study on this topic. We use C++ as tool to simulate the code structure and parameters. The results show that non-binary Root LDPC code provides higher threshold value as compare to binary Root LDPC code.

  • 272. Biernacki, Arkadiusz
    et al.
    Tutschku, Kurt
    Blekinge Institute of Technology, School of Computing.
    Comparative Performance Study of LTE Downlink Schedulers2014In: Wireless personal communications, ISSN 0929-6212, E-ISSN 1572-834X, Vol. 7, no 2, p. 585-599Article in journal (Refereed)
    Abstract [en]

    Long time evolution (LTE) represents an emerging and promising technology for providing broadband, mobile Internet access. Because of the limitation of available spectrum resource, high spectrum efficiency technologies such as channel-aware scheduling need to be explored. In this work, we evaluate the performance of three scheduling algorithms proposed for LTE downlink transmission. The evaluation takes place in mixed traffic scenarios and aims at exploring strengths and weaknesses of the proposed algorithms. Simulation results illustrate the importance of real-time traffic awareness by schedulers when a specified level of quality of service is required. The research shows that lack of prioritisation of multimedia traffic will lead to severe degradation of video and VoIP services even with a relatively low network load.

  • 273. Biernacki, Arkadiusz
    et al.
    Tutschku, Kurt
    Blekinge Institute of Technology, School of Computing.
    Performance of HTTP Video Streaming Under Different Network Conditions2014In: Multimedia tools and applications, ISSN 1380-7501, E-ISSN 1573-7721, Vol. 72, no 2, p. 1143-1166Article in journal (Refereed)
    Abstract [en]

    The Internet video sharing services have been gaining importance and increasing their share in the multimedia market. In order to compete effectively and provide broadcast television with a comparable level of quality, the Internet video should fulfil stringent quality of service (QoS) constraints. However, as the Internet video is based on packet transmission, it is influenced by delays, transmission errors, data losses and bandwidth limitations which can have a devastating influence on the perceived quality of the multimedia content. There are many works which describe the impact of network impairments on the Internet video. Nevertheless, little is known about how network conditions influence the video streamed by the currently popular services such as YouTube, where video is transmitted over reliable TCP/HTTP protocols. Therefore using a network simulator, we conducted an experimental evaluation of theHTTP based video transmission analysing how the network impairments mentioned above influence the streamed video. The experiments were validated against a network emulator supplied with real network traces. As a result of this work, we can state that the buffering strategies implemented by a video player are in many cases able to mitigate unfavourable network conditions what allow to play the streamed video smoothly. The results may serve Internet Service Providers so that they could tune their network characteristics in order to match the demand from HTTP video.

  • 274. Bigagli, Lorenzo
    et al.
    Sveinsdottir, Thordis
    Wessels, Bridgette
    Smallwood, Rod
    Linde, Peter
    Blekinge Institute of Technology, The Library.
    Sondervan, Jeroen
    Infrastructure and technology challenges2014Report (Refereed)
    Abstract [en]

    In this deliverable, we report on our work on infrastructural and technological barriers to Open Access and preservation of research data as identified by key stakeholder groups. Through a mix of qualitative, quantitative and document review methods, we identified five key barriers to successfully implementing Open Access to research data in Europe: data heterogeneity and issues of standardisation; accessibility and discoverability issues; data preservation and curation; data quality and assessability; and data security. We explore these issues in detail and present existing good practice, and technical and infrastructural solutions used to mitigate such barriers. This work was conducted within the EU FP7 funded project RECODE, which focuses on developing policy recommendations for Open Access to Research Data in Europe. In particular, this work is coordinated by RECODE Work Package 2 (WP2), Infrastructure and technology.

  • 275.
    Bilal, Muhammad
    et al.
    Blekinge Institute of Technology, School of Computing.
    Sankar, Ganesh
    Blekinge Institute of Technology, School of Computing.
    Trust & Security issues in Mobile banking and its effect on Customers2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context: The invention of mobile phones makes the human life easier. The purpose of this study is to identify security risks in mobile banking and to provide an authentication method for mobile banking transaction by using bio-metric mechanism. Objectives: Current mobile banking authentication is challenging and identified as a major security risk. Literature review shows that customer distrusts mobile banking due to security issues. The authors discuss security risks in current authentication methods in mobile banking. Methods: There are different methods and approaches to handle authentication in mobile banking. In this thesis, we propose a new approach of authentication in mobile banking. The strengths and weaknesses of existing approaches of authentication are identified with the help of Literature Review and interviews. The authors present basic transaction model and include security risks. By Literature Review it is found that finger print mechanism is a suitable method for authentication. Authors focus on authentication method and present a biometric scanning device which can identify the customer’s finger print thus enabling the customer to access mobile banking facility. Results: An authentication model is proposed through design process. The proposed biometric design was validated by conducting a workshop. The analysis of the workshop’s results showed that customer’s trust in security for mobile banking will be increased by finger print mechanism. To promote mobile banking, it is necessary to improve customer trust in terms of security. Conclusions: The authors concluded that, only authorized person will be able to use mobile banking services by incorporating bio-metric finger-print mechanism. By literature review and interview it was found that finger-print mechanism is more suitable than other ordinary mechanisms like login and password mechanism, SMS etc.

  • 276.
    Bilan, Carolina
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Hedberg, Carl
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Säkerhetshot och lösningar för privatpersoner med bredband2001Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    As more and more people gain access to broadband in their properties, the security threats get bigger. A lot more people also have computers that they carry home from work where they store important information concerning the company. The information stored on theese computers can be very easy to retrieve if you have the will and the skill to do it. Very few people have any knowledge how to protect themselves from theese threats.

  • 277. Binzenhöfer, Andreas
    et al.
    Schlosser, Daniel
    Tutschku, Kurt
    Fiedler, Markus
    An Autonomic Approach to Verify End-to-End Communication Quality2007Conference paper (Refereed)
    Abstract [en]

    -- To come --

  • 278.
    Birkestedt, Sara
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Systems and Software Engineering.
    Hansson, Andreas
    Blekinge Institute of Technology, School of Engineering, Department of Systems and Software Engineering.
    Can web-based statistic services be trusted?2004Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    A large number of statistic services exist today, which shows that there is a great interest in knowing more about the visitors on a web site. But how reliable is the result the services are giving? The hypothesis examined in the thesis is: Web-based statistic services do not show an accurate result The purpose of the thesis is to find out how accurate the web-based statistic services are regarding unique visitors and number of pages viewed. Our hope is that this thesis will bring more knowledge about the different statistic services that exists today and the problems surrounding them. We will also draw attention to the importance of knowing how your statistic software works to be able to interpret the results correctly. To investigate this, we chose to do practical tests on a selection of web-based statistic services. The services registered the traffic from the same web site during a test period. During the same period a control program registered the same things and stored the result in a database. In addition to the test, we have done an interview with a person working with web statistics. The investigation showed that there are big differences between the results from the web-based statistic services in the test and that none of them showed an accurate result, neither for the total number of page views nor unique visitors. This led us to the conclusion that web-based statistic services do not show an accurate result, which verifies our hypothesis. Also the interview confirmed that there is a problem with measuring web statistics.

  • 279.
    Biswas, Kamanashis
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Ali, Md. Liakat
    Blekinge Institute of Technology, School of Engineering, Department of Interaction and System Design.
    Security Threats in Mobile Ad Hoc Network2007Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    Mobile Ad Hoc Network (MANET) is a collection of communication devices or nodes that wish to communicate without any fixed infrastructure and pre-determined organization of available links. The nodes in MANET themselves are responsible for dynamically discovering other nodes to communicate. Although the ongoing trend is to adopt ad hoc networks for commercial uses due to their certain unique properties, the main challenge is the vulnerability to security attacks. A number of challenges like open peer-to-peer network architecture, stringent resource constraints, shared wireless medium, dynamic network topology etc. are posed in MANET. As MANET is quickly spreading for the property of its capability in forming temporary network without the aid of any established infrastructure or centralized administration, security challenges has become a primary concern to provide secure communication. In this thesis, we identify the existent security threats an ad hoc network faces, the security services required to be achieved and the countermeasures for attacks in each layer. To accomplish our goal, we have done literature survey in gathering information related to various types of attacks and solutions, as well as we have made comparative study to address the threats in different layers. Finally, we have identified the challenges and proposed solutions to overcome them. In our study, we have found that necessity of secure routing protocol is still a burning question. There is no general algorithm that suits well against the most commonly known attacks such as wormhole, rushing attack etc. In conclusion, we focus on the findings and future works which may be interesting for the researchers like robust key management, trust based systems, data security in different layer etc. However, in short, we can say that the complete security solution requires the prevention, detection and reaction mechanisms applied in MANET.

  • 280.
    Bjernklev, Christian
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    Dokumentärfilm om Warcraftspelaren 4K FuRy2005Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Warcraft är ett strategidataspel som massor av människor världen över ägnar sig åt. Sebastian Pesic (alias 4K FuRy) är en av världens bästa spelare och dataspelandet har blivit hans jobb. Dokumentärfilmen handlar om Sebastian Pesic och hans verklighet i Warcraftlaget 4Kings. Sebastian kommer att berätta om sina upplevelser och vi kommer att få se honom i action. Filmen kommer att ge en inblick i dataspelsvärlden som många inte ens vet om existerar. Ännu mindre att man kan tjäna stora pengar på att spela. Utomlands är uppmärksamheten för Warcraft större. Sebastian är mycket känd och han har fans runt om i hela världen. 4K FuRy is an alias and the man behind the name is Sebastian Pesic. He is a 19 year old young man who’s playing a strategy computer game called Warcraft. He is one of the best Warcraftplayers in the world and the computer playing has become his job. The documentary is about him and his reality in the Warcraft team 4 Kings. You will be able to follow Sebastian in his preparation for the biggest tournament of the year and you will be informed about the computergameworld that many don’t even know exists. Nor less that you can make a lot of money playing. Warcraft is well know and played of a lot of people worldwide and Sebastian has a lot of fans all around the globe.

  • 281.
    Björk, Rasmus
    et al.
    Blekinge Institute of Technology, School of Planning and Media Design.
    Luthra, Kunal
    Blekinge Institute of Technology, School of Planning and Media Design.
    GROWTH: En studie om hur man kan skapa liv i en post-apokalyptisk spelvärld2012Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Detta arbete undersöker frågan om hur man kan gå tillväga för att skapa en känsla av liv i en postapokalyptisk spelvärld med hjälp av färger, former och animationer i en egen spelproduktion. Arbetet tar upp flera teorier kring spelutveckling, post-apokalyptisk fiktion och färglära. Arbetet tar också upp verktyg som användes i produktionen av det spel som skapades och hur arbetet fortskred. Diskussionen som följer tar upp hur metoderna som användes påverkade resultatet och vad resultatet blev, samt hur man gick tillväga för att tolka det. Slutsatsen som dras i diskussionen visar att det är möjligt att skapa en känsla av liv i en postapokalyptisk spelvärld i en egen produktion och hur man kan förbättra de metoder som använts i en eventuell uppföljning av detta arbete. Nyckelord för detta arbete är; färgteori, post-apokalyps, spelproduktion och spelutveckling.

  • 282.
    Björklund, Benjamin
    et al.
    Blekinge Institute of Technology, School of Engineering, Department of Systems and Software Engineering.
    Nilsson, Simon Hjertson
    Blekinge Institute of Technology, School of Engineering, Department of Systems and Software Engineering.
    Customisable game interfaces impact on game experience2008Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    A graphical user interface (GUI) is the bridge between the software and the user. In video games the user interface must be easily understandable and apprehensive. In fact, if a user interface is poorly done it will often break the game and make the user choose another game. If a user has the ability to configure and change the look of the user interface, will it then result in improved game experience? That’s what we investigated in this thesis. To carry out the investigation we developed a fully customisable user interface to a game called “World of Warcraft”. We then compared the original “World of Warcraft” GUI with our own developed customisable GUI; this was conducted with a usability test with five participants. The result of the investigation showed that the participants in fact noticed an improvement in game experience and were intrigued to continue playing. With the customisable GUI the users felt that they could make more important abilities more accessible by either position them in a certain way or change the size of them.

  • 283. Björkman, Christina
    Feminist Research and Computer Science: Starting a Dialogue2005In: Journal of Information, Communication and Ethics in Society , ISSN 1477-996x, Vol. 3, no 4Article in journal (Refereed)
    Abstract [en]

    In this paper I discuss how feminist research focusing epistemological issues can be used within computer science (CS). I approach and explore epistemological questions in computer science through a number of themes, which I believe are important to the issues of what knowledge is produced as well as how it is produced and how knowledge is perceived in CS. I discuss for example paradigms and metaphors in computer science, the role of abstractions and the concept of naturalisation. In order to illustrate epistemological views in CS and how these can be questioned from the viewpoints of feminist epistemology, I also do a close reading and commenting of a recent book within the philosophy of computing.

  • 284. Björkman, Christina
    Invitation to Dialogue: Feminist Research meets Computer Science2005In: The Gender Politics of ICT / [ed] Archibald, Jacqueline; Emms, Judy; Grundy, Frances; Payne, Janet; Turner, Eva, Enfield: Middlesex University Press , 2005, p. 223-236Chapter in book (Refereed)
    Abstract [en]

    In this paper I discuss how feminist research focusing epistemological issues can be used within computer science (CS). I approach and explore epistemological questions in computer science through a number of themes, which I believe are important to the issues of what knowledge is produced as well as how it is produced and how knowledge is perceived in CS. I discuss for example paradigms and metaphors in computer science, the role of abstractions and the concept of naturalisation. In order to illustrate epistemological views in CS and how these can be questioned from the viewpoints of feminist epistemology, I also do a close reading and commenting of a recent book within the philosophy of computing

  • 285. Björkman, Christina
    Women in Computing in Sweden2007In: Wiley Encyclopedia of Computer Science and Engineering / [ed] Wah, Benjamin, London: John Wiley & Sons Inc , 2007Chapter in book (Refereed)
  • 286. Björkman, Christina
    et al.
    Elovaara, Pirjo
    Trojer, Lena
    Feminist Technoscience Rearranging in the Black Box of Information Technology2007In: Gender Designs IT. Construction and DEconstruction of Information Society Technology / [ed] Zorn, Isabel; Maass, Susanne; Rommes, Els; Schirmer, Carola; Schelhowe, Heidi, Wiesbaden: VS Verlag fur sozialwissenschaften , 2007Chapter in book (Refereed)
  • 287. Björkman, Christina
    et al.
    Trojer, Lena
    Blekinge Institute of Technology, School of Technoculture, Humanities and Planning.
    What does it mean to Know Computer Science? Perspectives from Gender Research2006In: tripleC (cognition, communication, co-operation): Journal for a Global Sustainable Information Society / Unified Theory of Information Research Group, ISSN 1726-670X, E-ISSN 1726-670X, Vol. 4, no 2, p. 316-327Article in journal (Refereed)
    Abstract [en]

    The epistemological basis for computer science (CS), on which research and education as well as development of applications are founded, are fundamental for its production of knowledge. In this paper we raise the issue of how gender research developed within science and technology can be used within computer science, to approach and discuss foundations of the discipline, and what the implications of this reflection are for CS education. After an introduction, which serves to motivate the questions raised, we discuss issues concerning the foundations of computer science. We then introduce gender research, as we use it, and present some points where this type of research can contribute to the question “What does it mean to know CS?”.

  • 288.
    Björnsson, Jens
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Analys av pop-ups genererade från adware2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    This thesis is about adware, which is very popular today. The adwares are used to, among other things, down- and upload files from other users on the Internet. One thing that most users of such programs are not aware of is that many of the adwares contain spyware. These spywares install themselves simultaneously with the adwares. Two of the spyware features is to generate pop-ups in the web browser and to direct advertisment from the users web habits. In some cases the users can protect themselves against pop-ups by installing additional software. To investigate these problems, five adwares have been exposed to five tests.

  • 289.
    Bladh, Thomas
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    StepTree: A File System Visualizer2002Independent thesis Advanced level (degree of Master (One Year))Student thesis
    Abstract [en]

    A 3D visualization tool for file system hierarchies is presented. The visualization technique used is based on the Tree-map / nested Venn diagram concept and is capable of visualizing metrics and attributes such as size, change and file type for thousands of nodes simultaneously. Size is visualized through node base area, change is visualized through the ghosting and hiding of unchanged nodes and file type is visualized through colors. Actions such as navigation and selection are performed exclusively in 3D. Finally a method for improving the visibility of nodes through the equalization of sibling nodes is proposed.

  • 290.
    Bladh, Thomas
    et al.
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    Carlsson, Johan
    Blekinge Institute of Technology, Department of Software Engineering and Computer Science.
    XML in the User Interface Context2001Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [en]

    The purpose of this thesis is to investigate to what extent XML (Extensible Markup Language) based languages are suitable for use as user interface definition languages in terms of their flexibility. The primary method used is qualitative analysis of scientific papers, literary resources on the target field, practical experiences as well as certain essential non-scientific literature such as standards documents and more practically oriented reference literature as well as on-line resources. XML has been shown to support international characters, the separation of user interface and logic as well as cross platform development very well. The derivative standards utilize these fundamental characteristics of XML in this context and add their own contribution to the mix. Our conclusion is that XML as such is ideally suited for creating flexible user interface definition languages. By flexible we mean that they exhibit some degree of all the flexibility factors reusability, customizability and localizability. The p articular XML based languages we have looked at, namely XUL (XML-based User Interface Language) and UIML (User Interface Markup Language) have also been found to add varying degrees of extra weight to the flexibility factors already found in XML. The findings indicate for example that the levels of abstraction in a particular derived language greatly affect the level of additional flexibility achieved through the use of the language in question.

  • 291.
    Bloom, Filip
    Blekinge Institute of Technology, Faculty of Computing, Department of Creative Technologies.
    Competitive Coevolution for micromanagement in StarCraft: Brood War2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Context. Interest in and research on neural networks and their capacity for finding solutions to nonlinear problems has increased greatly in recent years.

    Objectives. This thesis attempts to compare competitive coevolution to traditional neuroevolution in the game StarCraft: Brood War.

    Methods. Implementing and evolving AI-controlled players for the game StarCraft and evaluating their performance.

    Results. Fitness values and win rates against the default StarCraft AI and between the networks were gathered.

    Conclusions. The neural networks failed to improve under the given circumstances. The best networks performed on par with the default StarCraft AI.

  • 292.
    Boddapati, Venkatesh
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Classifying Environmental Sounds with Image Networks2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Context. Environmental Sound Recognition, unlike Speech Recognition, is an area that is still in the developing stages with respect to using Deep Learning methods. Sound can be converted into images by extracting spectrograms and the like. Object Recognition from images using deep Convolutional Neural Networks is a currently developing area holding high promise. The same technique has been studied and applied, but on image representations of sound.

    Objectives. In this study, investigation is done to determine the best possible accuracy of performing a sound classification task using existing deep Convolutional Neural Networks by comparing the data pre-processing parameters. Also, a novel method of combining different features into a single image is proposed and its effect tested. Lastly, the performance of an existing network that fuses Convolutional and Recurrent Neural architectures is tested on the selected datasets.

    Methods. In this, experiments were conducted to analyze the effects of data pre-processing parameters on the best possible accuracy with two CNNs. Also, experiment was also conducted to determine whether the proposed method of feature combination is beneficial or not. Finally, an experiment to test the performance of a combined network was conducted.

    Results. GoogLeNet had the highest classification accuracy of 73% on 50-class dataset and 90-93% on 10-class datasets. The sampling rate and frame length values of the respective datasets which contributed to the high scores are 16kHz, 40ms and 8kHz, 50ms respectively. The proposed combination of features does not improve the classification accuracy. The fused CRNN network could not achieve high accuracy on the selected datasets.

    Conclusions. It is concluded that deep networks designed for object recognition can be successfully used to classify environmental sounds and the pre-processing parameters’ values determined for achieving best accuracy. The novel method of feature combination does not significantly improve the accuracy when compared to spectrograms alone. The fused network which learns the special and temporal features from spectral images performs poorly in the classification task when compared to the convolutional network alone.

  • 293.
    Boeva, Veselka
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Angelova, Milena
    Technical University Sofia, BUL.
    Lavesson, Niklas
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Rosander, Oliver
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Tsiporkova, Elena
    Collective Center for the Belgian Technological Industry, BEL.
    Evolutionary clustering techniques for expertise mining scenarios2018In: ICAART 2018 - Proceedings of the 10th International Conference on Agents and Artificial Intelligence, Volume 2 / [ed] van den Herik J.,Rocha A.P., SciTePress , 2018, Vol. 2, p. 523-530Conference paper (Refereed)
    Abstract [en]

    The problem addressed in this article concerns the development of evolutionary clustering techniques that can be applied to adapt the existing clustering solution to a clustering of newly collected data elements. We are interested in clustering approaches that are specially suited for adapting clustering solutions in the expertise retrieval domain. This interest is inspired by practical applications such as expertise retrieval systems where the information available in the system database is periodically updated by extracting new data. The experts available in the system database are usually partitioned into a number of disjoint subject categories. It is becoming impractical to re-cluster this large volume of available information. Therefore, the objective is to update the existing expert partitioning by the clustering produced on the newly extracted experts. Three different evolutionary clustering techniques are considered to be suitable for this scenario. The proposed techniques are initially evaluated by applying the algorithms on data extracted from the PubMed repository. Copyright © 2018 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved.

  • 294. Boeva, Veselka
    et al.
    Angelova, Milena
    Technical University Sofia Branch Plovdiv, BUL.
    Tsiporkova, Elena
    Sirris, Brussels, BEL.
    A split-merge evolutionary clustering algorithm2019In: ICAART 2019 - Proceedings of the 11th International Conference on Agents and Artificial Intelligence, SciTePress , 2019, Vol. 2, p. 337-346Conference paper (Refereed)
    Abstract [en]

    In this article we propose a bipartite correlation clustering technique that can be used to adapt the existing clustering solution to a clustering of newly collected data elements. The proposed technique is supposed to provide the flexibility to compute clusters on a new portion of data collected over a defined time period and to update the existing clustering solution by the computed new one. Such an updating clustering should better reflect the current characteristics of the data by being able to examine clusters occurring in the considered time period and eventually capture interesting trends in the area. For example, some clusters will be updated by merging with ones from newly constructed clustering while others will be transformed by splitting their elements among several new clusters. The proposed clustering algorithm, entitled Split-Merge Evolutionary Clustering, is evaluated and compared to another bipartite correlation clustering technique (PivotBiCluster) on two different case studies: expertise retrieval and patient profiling in healthcare. Copyright © 2019 by SCITEPRESS - Science and Technology Publications, Lda. All rights reserved

  • 295. Boeva, Veselka
    et al.
    Ivanova, Petia
    Lavesson, Niklas
    A Hybrid Computational Method for the Identification of Cell Cycle-regulated Genes2010Conference paper (Refereed)
    Abstract [en]

    Gene expression microarrays are the most commonly available source of high-throughput biological data. They have been widely employed in recent years for the definition of cell cycle regulated (or periodically expressed) subsets of the genome in a number of different organisms. These have driven the development of various computational methods for identifying periodical expressed genes. However, the agreement is remarkably poor when different computational methods are applied to the same data. In view of this, we are motivated to propose herein a hybrid computational method targeting the identification of periodically expressed genes, which is based on a hybrid aggregation of estimations, generated by different computational methods. The proposed hybrid method is benchmarked against three other computational methods for the identification of periodically expressed genes: statistical tests for regulation and periodicity and a combined test for regulation and periodicity. The hybrid method is shown, together with the combined test, to statistically significantly outperform the statistical test for periodicity. However, the hybrid method is also demonstrated to be significantly better than the combined test for regulation and periodicity.

  • 296.
    Boeva, Veselka
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Lundberg, Lars
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Angelova, Milena
    TU of Sofia, BUL.
    Kohstall, Jan
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Cluster Validation Measures for Label Noise Filtering2018In: 9th International Conference on Intelligent Systems 2018: Theory, Research and Innovation in Applications, IS 2018 - Proceedings / [ed] JardimGoncalves, R; Mendonca, JP; Jotsov, V; Marques, M; Martins, J; Bierwolf, R, Institute of Electrical and Electronics Engineers Inc. , 2018, p. 109-116Conference paper (Refereed)
    Abstract [en]

    Cluster validation measures are designed to find the partitioning that best fits the underlying data. In this paper, we show that these well-known and scientifically proven validation measures can also be used in a different context, i.e., for filtering mislabeled instances or class outliers prior to training in super-vised learning problems. A technique, entitled CVI-based Outlier Filtering, is proposed in which mislabeled instances are identified and eliminated from the training set, and a classification hypothesis is then built from the set of remaining instances. The proposed approach assigns each instance several cluster validation scores representing its potential of being an outlier with respect to the clustering properties the used validation measures assess. We examine CVI-based Outlier Filtering and compare it against the LOF detection method on ten data sets from the UCI data repository using five well-known learning algorithms and three different cluster validation indices. In addition, we study two approaches for filtering mislabeled instances: local and global. Our results show that for most learning algorithms and data sets, the proposed CVI-based outlier filtering algorithm outperforms the baseline method (LOF). The greatest increase in classification accuracy has been achieved by combining at least two of the used cluster validation indices and global filtering of mislabeled instances. © 2018 IEEE.

  • 297.
    Boeva, Veselka
    et al.
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering. Blekinge Inst Technol, Comp Sci & Engn Dept, Karlskrona, Sweden..
    Lundberg, Lars
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering. Blekinge Inst Technol, Comp Sci & Engn Dept, Karlskrona, Sweden..
    Kota, Sai M. Harsha
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Sköld, Lars
    Telenor , SWE.
    Analysis of Organizational Structure through Cluster Validation Techniques Evaluation of email communications at an organizational level2017In: 2017 17TH IEEE INTERNATIONAL CONFERENCE ON DATA MINING WORKSHOPS (ICDMW 2017) / [ed] Gottumukkala, R Ning, X Dong, G Raghavan, V Aluru, S Karypis, G Miele, L Wu, X, IEEE , 2017, p. 170-176Conference paper (Refereed)
    Abstract [en]

    In this work, we report an ongoing study that aims to apply cluster validation measures for analyzing email communications at an organizational level of a company. This analysis can be used to evaluate the company structure and to produce further recommendations for structural improvements. Our initial evaluations, based on data in the forms of emails logs and organizational structure for a large European telecommunication company, show that cluster validation techniques can be useful tools for assessing the organizational structure using objective analysis of internal email communications, and for simulating and studying different reorganization scenarios.

  • 298.
    Bogale, Helen Yeshiwas
    et al.
    Blekinge Institute of Technology, School of Computing.
    Ahmed, Zohaib
    Blekinge Institute of Technology, School of Computing.
    A Framework for Security Requirements: Security Requirements Categorization and Misuse Cases2011Independent thesis Advanced level (degree of Master (Two Years))Student thesis
    Abstract [en]

    Context: Security Requirements engineering is necessary to achieve secure software systems. Many techniques and approaches have been proposed to elicit security requirements in the initial phases of development. With the growing importance of security and immense increase in security breaches over the past few years, researchers and practitioners have been striving to achieve a mature process of coping with security requirements. Much of the activities in this regard are seen in academia but industry still seems to be lacking in giving the required importance to security requirements engineering. That is why, security requirements engineering is still not always considered as a central part of requirements engineering. This study is targeted to bridge this gap between academia and industry in terms of security requirements engineering and to provide a concrete approach to efficiently elicit and specify security requirements. The Misuse case technique is proposed for this purpose. However it lacks in providing guidelines for enabling scalable use. This limitation has been addressed to achieve a mature process of security requirements elicitation. Objectives: In this study, we propose a framework to elicit security requirements early in the software development using misuse case technique. Objective is to make misuse case technique scalable and applicable to the real-world projects. The proposed framework was presented to two representatives from the Swedish Armed Forces (SWAF). The feedback received from the representatives was utilized to refine, update and finalize the framework. Methods: The study involved a systematic review to gain an insight of the academic perspective in the area of study. Document extraction was adopted to observe the industrial trends in the said subject. These were the software requirements specification documents of the real-world systems. Document extraction was supported with informed brainstorming because the study revolved around misuse case technique and informed brainstorming is considered to be the most suitable technique for this purpose. A workshop was conducted with two representatives of Swedish Armed Forces followed by two subsequent asynchronous communication rounds and a facilitated session to get feedback about the proposed solution. This feedback was utilized to refine, update and finalize the proposed solution. Results: The results of the systematic review were organized in tabular forms for a clear understanding and easy analysis. A security requirements categorization was obtained as a result which was finalized after an initial validation with the help of real-world projects. Furthermore, a framework was proposed utilizing this categorization to address the limitations of misuse case technique. The framework was created and refined through workshop and different communication rounds with representatives of SWAF. Their feedback was used as input to further improve the usefulness and usability aspects of the framework. Conclusions: The significance of security requirements engineering is undisputedly accepted both in academia and industry. However, the area is not a subject of practice in industrial projects. The reasons include lack of mature processes as well as expensive and time consuming solutions. Lack of empirical evidences adds to the problems. The conducted study and proposed process of dealing with this issue is considered as a one step forward towards addressing the challenges.

  • 299.
    Boinapally, Kashyap
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science.
    Security Certificate Renewal Management2019Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Context. An SSL encrypted client-server communication is necessary to maintain the security and privacy of the communication. For an SSL encryption to work, there should be a security certificate which has a certain expiry period. Periodic renewal of the certificate after its expiry is a waste of time and an effort on part of the company.

    Objectives. In this study, a new system has been developed and implemented, which sends a certificate during prior communication and does not wait for the certificate to expire. Automating the process to a certain extent was done to not compromise the security of the system and to speed up the process and reduce the downtime.

    Methods. Experiments have been conducted to test the new system and compare it to the old system. The experiments were conducted to analyze the packets and the downtime occurring from certificate renewal.

    Results. The results of the experiments show that there is a significant reduction in downtime. This was achieved due to the implementation of the new system and semi-automation

    Conclusions. The system has been implemented, and it greatly reduces the downtime occurring due to the expiry of the security certificates. Semi-Automation has been done to not hamper the security and make the system robust.

  • 300. Boldt, Martin
    Privacy-Invasive Software2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    As computers are increasingly more integrated into our daily lives we become more dependent on software. This situation is exploited by villainous actors on the Internet that distribute malicious software in search for fast financial gains on the expense of deceived computer users. As a result, computer users need more accurate and aiding mechanisms to assist them when separating legitimate software from its unwanted counterparts. However, such separations are complicated due to a greyzone of software that exists between legitimate and purely malicious software. The software in this greyzone often vaguely labeled spyware. This work introduce both user-aiding mechanisms and an attempt to clarify the greyzone by introducing the concept of privacy-invasive software (PIS) as a category of software that ignores the users’ right to be left alone. Such software is distributed with a specific intent (often of commercial nature), which negatively affect the users to various degree. PIS is therefore classified with respect to the degree of informed consent and the amount of negative consequences for the users. To mitigate the effects from PIS, two novel mechanisms for safeguarding user consent during software installation are introduced; a collaborative software reputation system; and an automated End User License Agreement (EULA) classification. In the software reputation system, users collaborate by sharing experiences of previously used software programs, allowing new users to rely on the collective experience when installing software. The EULA classification generalizes patterns from a set of both legitimate and questionable software EULAs, so that computer users can automatically classify previously unknown EULAs as belonging to legitimate software or not. Both techniques increase user awareness about software program behavior, which allow users to make more informed decisions concerning software installations, which arguably reduces the threat from PIS. We present experimental results showing the ability of a set of machine learning algorithms ability to perform automated EULA classification. In addition, we also present a prototype implementation of a software reputation system, together with simulation results of the large-scale use of the system.

3456789 251 - 300 of 2518
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf