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2012

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Articles 1801 - 1830 of 1947

Full-Text Articles in Computer Sciences

Modeling And Control Of Discrete Event Systems Using Finite State Machines With Variables And Their Applications In Power Grids, Junhui Zhao, Le Yi Wang, Zhong Chen, Feng Lin, Hongwei Zhang Jan 2012

Modeling And Control Of Discrete Event Systems Using Finite State Machines With Variables And Their Applications In Power Grids, Junhui Zhao, Le Yi Wang, Zhong Chen, Feng Lin, Hongwei Zhang

Electrical & Computer Engineering and Computer Science Faculty Publications

Control theories for discrete event systems modeled as finite state machines have been well developed to address various fundamental control issues. However, finite state machine model has long suffered from the problem of state explosion that renders it unsuitable for some practical applications. In an attempt to mitigate the state explosion problem, we propose an efficient representation that appends finite sets of variables to finite state machines in modeling discrete event systems. We also present the control synthesis techniques for such finite state machines with variables (FSMwV). We first present our notion and means of control under this representation. We …


Structural Analysis In Multi-Relational Social Networks, Bingtian Dai, Freddy Chua, Ee Peng Lim Jan 2012

Structural Analysis In Multi-Relational Social Networks, Bingtian Dai, Freddy Chua, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Modern social networks often consist of multiple relations among individuals. Understanding the structure of such multi-relational network is essential. In sociology, one way of structural analysis is to identify different positions and roles using blockmodels. In this paper, we generalize stochastic blockmodels to Generalized Stochastic Blockmodels (GSBM) for performing positional and role analysis on multi-relational networks. Our GSBM generalizes many different kinds of Multivariate Probability Distribution Function (MVPDF) to model different kinds of multirelational networks. In particular, we propose to use multivariate Poisson distribution for multi-relational social networks.


Content Contribution In Social Media: The Case Of Youtube, Qian Tang, Bin Gu, Andrew B. Whinston Jan 2012

Content Contribution In Social Media: The Case Of Youtube, Qian Tang, Bin Gu, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

Social media allows individuals and businesses to contribute contents for public viewing. However, little is known about the underlying incentives that why content providers derive utilities from such activities. In this study, we build a dynamic structural model to recover the utility function for content providers. Our model distinguishes short-term payoffs based on ad revenue sharing from long-term payoffs driven by content providers' reputation. The model was estimated using a panel data of 914 top 1000 video providers on You Tube from Jun 7th, 2010, to Aug 7th, 2011 since top providers are more likely to be encouraged by these …


Kinect Hand Recognition And Tracking, Alex Drake Jan 2012

Kinect Hand Recognition And Tracking, Alex Drake

All Computer Science and Engineering Research

he goal of this research project was to be able to identify and track a hand using the depth image from a Microsoft Kinect. The ability to do this would have uses in sign language recognition, rehabilitation, and gesture recognition amongst others. The Microsoft Kinect is currently capable of identifying and tracking whole bodies. Our approach was to follow the method that Microsoft used but apply it to detailed hand recognition instead of the body. The basic strategy they used was to take a large amount of labeled depth data and build a decision tree to identify which part of …


Early Warning System: Relay Sensor Deployment & Network Reliability Analysis, Zhicheng Yang Jan 2012

Early Warning System: Relay Sensor Deployment & Network Reliability Analysis, Zhicheng Yang

All Computer Science and Engineering Research

In this project, we continued Dr. Chipara's study, which developed an early warning system (EWS) to detect the vital signs of patients in order to help doctors to intervene in time [1]. Since the number of wards increased, the environment our system faced with became more complicated and our network became more sensitive. This project focused on finding reasons on the relays that didn't work and doing a reliability analysis on the network in one ward our study covered.


Limitations And Solutions For Real-Time Local Inter-Domain Communication In Xen, Sisu Xi, Chong Li, Chenyang Lu, Christopher Gill Jan 2012

Limitations And Solutions For Real-Time Local Inter-Domain Communication In Xen, Sisu Xi, Chong Li, Chenyang Lu, Christopher Gill

All Computer Science and Engineering Research

As computer hardware becomes increasingly powerful, there is an ongoing trend towards integrating complex, legacy real-time systems using fewer hosts through virtualization. Especially in embedded systems domains such as avionics and automotive engineering, this kind of system integration can greatly reduce system weight, cost, and power requirements. When systems are integrated in this manner, network communication may become local inter-domain communication (IDC) within the same host. This paper examines the limitations of inter-domain communication in Xen, a widely used open-source virtual machine monitor (VMM) that recently has been extended to support real-time domain scheduling. We find that both the VMM …


A New Efficient Optimistic Fair Exchange Protocol Without Random Oracles, Qiong Huang, Guomin Yang, Duncan S. Wong, Willy Susilo Jan 2012

A New Efficient Optimistic Fair Exchange Protocol Without Random Oracles, Qiong Huang, Guomin Yang, Duncan S. Wong, Willy Susilo

Research Collection School Of Computing and Information Systems

Optimistic fair exchange (OFE) is a kind of protocols to solve the problem of fair exchange between two parties. Most of the previous work on this topic are provably secure in the random oracle model. In this work, we propose a new construction of OFE from another cryptographic primitive, called time capsule signature. The construction is efficient and brings almost no overhead other than the primitive itself. The security of our new construction is based on that of the underlying primitive without relying on the random oracle heuristic. Applying our generic construction to the time capsule signature scheme recently proposed …


Topic Based Query Suggestions For Video Search, Kong-Wah Wan, Ah-Hwee Tan, Joo-Hwee Lim, Liang-Tien Chia Jan 2012

Topic Based Query Suggestions For Video Search, Kong-Wah Wan, Ah-Hwee Tan, Joo-Hwee Lim, Liang-Tien Chia

Research Collection School Of Computing and Information Systems

Query suggestion is an assistive technology mechanism commonly used in search engines to enable a user to formulate their search queries by predicting or completing the next few query words that the user is likely to type. In most implementations, the suggestions are mined from query log and use some simple measure of query similarity such as query frequency or lexicographical matching. In this paper, we propose an alternative method of presenting query suggestions by their thematic topics. Our method adopts a document-centric approach to mine topics in the corpus, and does not require the availability of a query log. …


A Survey On Privacy Frameworks For Rfid Authentication, Chunhua Su, Yingjiu Li, Yunlei Zhao, Robert H. Deng, Yiming Zhao, Jianying Zhou Jan 2012

A Survey On Privacy Frameworks For Rfid Authentication, Chunhua Su, Yingjiu Li, Yunlei Zhao, Robert H. Deng, Yiming Zhao, Jianying Zhou

Research Collection School Of Computing and Information Systems

Due to rapid growth of RFID system applications, the security and privacy problems become more and more important to guarantee the validity of RFID systems. Without introducing proper privacy protection mechanisms, widespread deployment of RFID could raise privacy concerns to both companies and individuals. As a fundamental issue for the design and analysis of secure RFID systems, some formal RFID privacy frameworks were proposed in recent years to give the principles for evaluating the security and privacy in RFID system. However, readers can be confused with so many proposed frameworks. In this paper, we make a comparative and survey study …


Information Extraction From Text, Jing Jiang Jan 2012

Information Extraction From Text, Jing Jiang

Research Collection School Of Computing and Information Systems

Information extraction is the task of finding structured information from unstructured or semi-structured text. It is an important task in text mining and has been extensively studied in various research communities including natural language processing, information retrieval and Web mining. It has a wide range of applications in domains such as biomedical literature mining and business intelligence. Two fundamental tasks of information extraction are named entity recognition and relation extraction. The former refers to finding names of entities such as people, organizations and locations. The latter refers to finding the semantic relations such as FounderOf and HeadquarteredIn between entities. In …


Multi-Party Multi-Period Supply Chain Coordination, Thin Yin Leong, Michelle Lee Fong Cheong Jan 2012

Multi-Party Multi-Period Supply Chain Coordination, Thin Yin Leong, Michelle Lee Fong Cheong

Research Collection School Of Computing and Information Systems

We apply combinatorial auction as a coordination mechanism to smooth demands placed on suppliers' limited production capacities, allowing several manufacturers to share common suppliers effectively. Products are bidders bidding for parts from suppliers, consuming their capacities in different time periods. The fourth party logistic (4PL) provider acts as the auctioneer to coordinate bids and perform price iterations. We leverage on the strong links between the Lagrangian relaxation method and combinatorial auction, where the Lagrange multipliers serve as the supply capacity reserve prices, to balance the demand and supply of capacities. To prevent cyclic behaviour and to increase convergence speed, we …


Mining Diversity On Social Media Networks, Lu Liu, Feida Zhu, Meng Jiang, Jiawei Han, Lifeng Sun, Shiqiang Yang Jan 2012

Mining Diversity On Social Media Networks, Lu Liu, Feida Zhu, Meng Jiang, Jiawei Han, Lifeng Sun, Shiqiang Yang

Research Collection School Of Computing and Information Systems

The fast development of multimedia technology and increasing availability of network bandwidth has given rise to an abundance of network data as a result of all the ever-booming social media and social websites in recent years, e.g., Flickr, Youtube, MySpace, Facebook, etc. Social network analysis has therefore become a critical problem attracting enthusiasm from both academia and industry. However, an important measure that captures a participant’s diversity in the network has been largely neglected in previous studies. Namely, diversity characterizes how diverse a given node connects with its peers. In this paper, we give a comprehensive study of this concept. …


A Sentiment Analysis Of Singapore Presidential Election 2011 Using Twitter Data With Census Correction, Murphy Junyu Choy, Michelle Lee Fong Cheong, Nang Laik Ma, Ping Shung Koo Jan 2012

A Sentiment Analysis Of Singapore Presidential Election 2011 Using Twitter Data With Census Correction, Murphy Junyu Choy, Michelle Lee Fong Cheong, Nang Laik Ma, Ping Shung Koo

Research Collection School Of Computing and Information Systems

Sentiment analysis is a new area in text analytics where it focuses on the analysis and understanding of the human emotions from the text patterns. This new form of analysis has been widely adopted in customer relationship management especially in the context of complaint management. However, sentiment analysis using Twitter data has remained extremely difficult to manage due to sampling biasness. In this paper, we will discuss about the application of reweighting techniques in conjunction with online sentiment divisions to predict the vote percentage that individual presidential candidate in Singapore will receive in the Presidential Election 2011. There will be …


Dynamic Secure Cloud Storage With Provenance, Sherman S. M. Chow, Cheng-Kang Chu, Xinyi Huang, Jianying Zhou, Robert H. Deng Jan 2012

Dynamic Secure Cloud Storage With Provenance, Sherman S. M. Chow, Cheng-Kang Chu, Xinyi Huang, Jianying Zhou, Robert H. Deng

Research Collection School Of Computing and Information Systems

One concern in using cloud storage is that the sensitive data should be confidential to the servers which are outside the trust domain of data owners. Another issue is that the user may want to preserve his/her anonymity in the sharing or accessing of the data (such as in Web 2.0 applications). To fully enjoy the benefits of cloud storage, we need a confidential data sharing mechanism which is fine-grained (one can specify who can access which classes of his/her encrypted files), dynamic (the total number of users is not fixed in the setup, and any new user can decrypt …


Evaluating The Use Of A Mobile Annotation System For Geography Education, Dion Hoe-Lian Goh, Khasfariyati Razikin, Chei Sian Lee, Ee Peng Lim, Kalyani Chatterjea, Chew-Hung Chang Jan 2012

Evaluating The Use Of A Mobile Annotation System For Geography Education, Dion Hoe-Lian Goh, Khasfariyati Razikin, Chei Sian Lee, Ee Peng Lim, Kalyani Chatterjea, Chew-Hung Chang

Research Collection School Of Computing and Information Systems

Mobile devices used in educational settings are usually employed within a collaborative learning activity in which learning takes place in the form of social interactions between team members while performing a shared task. The authors aim to introduce MobiTOP (Mobile Tagging of Objects and People), a mobile annotation system that allows users to contribute and share geospatial multimedia annotations via mobile devices. Field observations and interviews were conducted. A group of trainee teachers involved in a geography field study were instructed to identify rock formations by collaborating with each other using the MobiTOP system. The trainee teachers who were in …


Who Is Retweeting The Tweeters? Modeling, Originating, And Promoting Behaviors In The Twitter Network, Achananuparp Palakorn, Ee Peng Lim, Jing Jiang, Tuan Anh Hoang Jan 2012

Who Is Retweeting The Tweeters? Modeling, Originating, And Promoting Behaviors In The Twitter Network, Achananuparp Palakorn, Ee Peng Lim, Jing Jiang, Tuan Anh Hoang

Research Collection School Of Computing and Information Systems

Real-time microblogging systems such as Twitter offer users an easy and lightweight means to exchange information. Instead of writing formal and lengthy messages, microbloggers prefer to frequently broadcast several short messages to be read by other users. Only when messages are interesting, are they propagated further by the readers. In this article, we examine user behavior relevant to information propagation through microblogging. We specifically use retweeting activities among Twitter users to define and model originating and promoting behavior. We propose a basic model for measuring the two behaviors, a mutual dependency model, which considers the mutual relationships between the two …


Optimal Decision Making For Online Referral Marketing, Zhiling Guo Jan 2012

Optimal Decision Making For Online Referral Marketing, Zhiling Guo

Research Collection School Of Computing and Information Systems

Widely available web 2.0 technologies not only bring rich and interactive user experiences, but also easily help users advertise products or services on their own blogs and social network webpages. Online referral marketing, for example, is a business practice that rewards customers who successfully refer other customers to a website or upon completion of a sale usually via their own social contacts. The referral rewards come in different forms such as shopping vouchers, redeemable points, discounts, prizes, cash payments, etc. We develop an analytical model to evaluate the business potential of incorporating an online referral marketing program into the firm's …


A Fuzzy Logic Multi-Criteria Decision Framework For Selecting It Service Providers, Amir Karami, Zhiling Guo Jan 2012

A Fuzzy Logic Multi-Criteria Decision Framework For Selecting It Service Providers, Amir Karami, Zhiling Guo

Research Collection School Of Computing and Information Systems

Selecting IT service providers in information systems outsourcing involves both qualitative and quantitative evaluations. This paper proposes an integrated multi-criteria decision-making (MCDM) framework to effectively handle uncertainty and subjectivity in the vendor selection process. The proposed methods apply fuzzy logic approach to integrate qualitative survey data into traditional multi-criteria decision models such as data envelope analysis (DEA), analytical hierarchy process (AHP) methods, and TOPSIS. Based on case studies from Iranian banking industry, we empirically test the proposed framework and show it is superior to existing methods. We demonstrate that the fuzzy logic approach provides a robust analysis for vendor selection …


Road: A New Spatial Object Search Framework For Road Networks, Ken C. K. Lee, Wang-Chien Lee, Baihua Zheng, Yuan Tian Jan 2012

Road: A New Spatial Object Search Framework For Road Networks, Ken C. K. Lee, Wang-Chien Lee, Baihua Zheng, Yuan Tian

Research Collection School Of Computing and Information Systems

In this paper, we present a new system framework called ROAD for spatial object search on road networks. ROAD is extensible to diverse object types and efficient for processing various location-dependent spatial queries (LDSQs), as it maintains objects separately from a given network and adopts an effective search space pruning technique. Based on our analysis on the two essential operations for LDSQ processing, namely, network traversal and object lookup, ROAD organizes a large road network as a hierarchy of interconnected regional subnetworks (called Rnets). Each Rnet is augmented with 1) shortcuts and 2) object abstracts to accelerate network traversals and …


Imbalance Challenge Of Enacting Information Privacy Safeguards In Healthcare: A Grounded Theory Approach, Rachida Parks, Heng Xu, Chao-Hsien Chu Jan 2012

Imbalance Challenge Of Enacting Information Privacy Safeguards In Healthcare: A Grounded Theory Approach, Rachida Parks, Heng Xu, Chao-Hsien Chu

Research Collection School Of Computing and Information Systems

Healthcare organizations face significant challenges in designing and implementing the appropriate safeguards to mitigate information privacy threats. While many studies examined various technical and behavioral safeguards to protect the confidentiality and privacy of patient information, very little is known about the actual outcomes and implications of the privacy practices in which organizations engage. There is little research theoretically explaining the outcomes of enacting privacy safeguards and subsequent effects on privacy compliance. This paper reports the results of a grounded theory study investigating the intended consequences (positive impacts) and unintended (negative impacts) consequences of enacting privacy safeguards in healthcare organizations. An …


Modeling And Compressing 3-D Facial Expressions Using Geometry Videos, Jiazhi Xia, Dao T. P. Quynh, Ying He, Xiaoming Chen, Steven C. H. Hoi Jan 2012

Modeling And Compressing 3-D Facial Expressions Using Geometry Videos, Jiazhi Xia, Dao T. P. Quynh, Ying He, Xiaoming Chen, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

In this paper, we present a novel geometry video (GV) framework to model and compress 3-D facial expressions. GV bridges the gap of 3-D motion data and 2-D video, and provides a natural way to apply the well-studied video processing techniques to motion data processing. Our framework includes a set of algorithms to construct GVs, such as hole filling, geodesic-based face segmentation, expression-invariant parameterization (EIP), and GV compression. Our EIP algorithm can guarantee the exact correspondence of the salient features (eyes, mouth, and nose) in different frames, which leads to GVs with better spatial and temporal coherence than that of …


Learning Bregman Distance Functions For Semi-Supervised Clustering, Lei Wu, Chu Hong Hoi, Rong Jin, Jianke Zhu, N. Yu Jan 2012

Learning Bregman Distance Functions For Semi-Supervised Clustering, Lei Wu, Chu Hong Hoi, Rong Jin, Jianke Zhu, N. Yu

Research Collection School Of Computing and Information Systems

Learning distance functions with side information plays a key role in many data mining applications. Conventional distance metric learning approaches often assume that the target distance function is represented in some form of Mahalanobis distance. These approaches usually work well when data are in low dimensionality, but often become computationally expensive or even infeasible when handling high-dimensional data. In this paper, we propose a novel scheme of learning nonlinear distance functions with side information. It aims to learn a Bregman distance function using a nonparametric approach that is similar to Support Vector Machines. We emphasize that the proposed scheme is …


Preface: Trends In Natural And Machine Intelligence, Jonathan H. Chan, Ah-Hwee Tan Jan 2012

Preface: Trends In Natural And Machine Intelligence, Jonathan H. Chan, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Trends in natural and machine intelligence are increasingly reflecting a convergence in these two well-established fields of study. The Third International Neural Network Society Winter Conference (INNS-WC 2012) was held in Bangkok, Thailand, on October 3-5, 2012. INNS-WC2012, with an aim to bring together scientists, practitioners, and students worldwide, to discuss the past, present, and future challenges and trends in the area of natural and machine intelligence. This event has been a bi-annual conference of the International Neural Network Society (INNS) to provide a forum for international researchers to exchange latest ideas and advances on neural networks and related discipline.


The Interactions Among Information Technology Organizational Learning, Project Learning, And Project Success, Donald Stuart Mckay Jan 2012

The Interactions Among Information Technology Organizational Learning, Project Learning, And Project Success, Donald Stuart Mckay

CCAC Theses and Dissertations

Knowledge gained from completed information technology (IT) projects was not often shared with emerging project teams. Learning lessons from other project teams was not pursued because people lack time, do not see value in learning, fear a potentially painful process, and had concerns that sharing knowledge will hurt their career. Leaders could change the situation; however organizational leaders have not seen value in project learning and have not made it a priority. Yet, if a relationship existed among IT project success variables (PSVs) organizational learning factors (OLFs) and project learning practices (PLPs) then IT leaders may take greater interest in …


Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar Jan 2012

Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a differential evolution (DE) algorithm for optimizing the placement and power of the pilot tones that are utilized by a least square (LS) algorithm for channel estimation in multiple-input and multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. Computer simulations demonstrated that the performance of the LS algorithm was increased by optimizing the pilot tones with the DE algorithm instead of locating them orthogonally. We used the upper bound of the mean square error (MSE) as a fitness function of the DE algorithm for optimization tasks. With the use of an upper bound, it is not necessary …


An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab Jan 2012

An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab

Turkish Journal of Electrical Engineering and Computer Sciences

FastSLAM is a framework for simultaneous localization and mapping (SLAM) using a Rao-Blackwellized particle filter. However, FastSLAM degenerates over time. This degeneracy is due to the fact that a particle set estimating the pose of the robot loses its diversity. One of the main reasons for losing particle diversity in FastSLAM is sample impoverishment. In this case, most of the particle weights are insignificant. Another problem of FastSLAM relates to the design of an extended Kalman filter (EKF) for the landmark position's estimation. The performance of the EKF and the quality of the estimation depend heavily on correct a priori …


Action-Reaction Based Parameters Identification And States Estimation Of Flexible Systems, Islam Shoukry, Emrah Deni̇z Kunt, Asif Sabanovic Jan 2012

Action-Reaction Based Parameters Identification And States Estimation Of Flexible Systems, Islam Shoukry, Emrah Deni̇z Kunt, Asif Sabanovic

Turkish Journal of Electrical Engineering and Computer Sciences

This work attempts to identify and estimate flexible system's parameters and states by a simple utilization of the Action-Reaction law of dynamical systems. Attached actuator to a dynamical system or environmental interaction imposes an action that is instantaneously followed by a dynamical system reaction. The dynamical system's reaction carries full information about the dynamical system including system parameters, dynamics and externally applied forces that arise due to system interaction with the environment. This in turn implies that the dynamical system's reaction can be considered as a natural feedback as it carries full coupled information about the dynamical system. The idea …


Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay Jan 2012

Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay

Turkish Journal of Electrical Engineering and Computer Sciences

Hash functions are one of the ubiquitous cryptographic functions used widely for various applications such as digital signatures, data integrity, authentication protocols, MAC algorithms, RNGs, etc. Hash functions are supposed to be one-way, i.e., preimage resistant. One interesting property of hash functions is that they process arbitrary-length messages into fixed-length outputs. In general, this can be achieved mostly by applying compression functions onto the message blocks of fixed length, recursively. The length of the message is incorporated as padding in the last block prior to the hash, a procedure called the Merkle-Damgard strengthening. In this paper, we introduce a new …


Reducing Electromagnetic Interferences In Flyback Ac-Dc Converters Based On The Frequency Modulation Technique, Gökhan Çabuk, Selçuk Kilinç Jan 2012

Reducing Electromagnetic Interferences In Flyback Ac-Dc Converters Based On The Frequency Modulation Technique, Gökhan Çabuk, Selçuk Kilinç

Turkish Journal of Electrical Engineering and Computer Sciences

One of the most preferable types of switched-mode power supplies (SMPS) is the flyback converter, due to its wide range of application areas. Properties such as low cost, provision of multiple output voltage terminals, and higher efficiencies make it important, and hence its usage in technologies including cell phone chargers, personal computers, set-top boxes, and televisions is increasing. Special attention should be paid to the design of this type of converter due to its working principles and electromagnetic interference (EMI) performance. Rapid switching of high current and high voltage during the operation of SMPS causes an EMI problem. The level …


A Robust Adaptive Fuzzy Control Of A Unified Power Flow Controller, Sebaa Morsli, Allaoui Tayeb, Denai Mouloud, Chaker Abdelkader Jan 2012

A Robust Adaptive Fuzzy Control Of A Unified Power Flow Controller, Sebaa Morsli, Allaoui Tayeb, Denai Mouloud, Chaker Abdelkader

Turkish Journal of Electrical Engineering and Computer Sciences

This paper investigates the control of a unified power flow controller (UPFC) to improve the stability of a power system, hence providing security under increased power flow conditions. The proposed control methods include a direct proportional and integral (PI) controller and an adaptive fuzzy logic controller (AFLC). The performances of these controllers were evaluated under different operating conditions of the power system and the results demonstrated that PI and AFLC are very effective in improving the transient power system stability and very robust against variable transmission line parameters.