Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2016

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 11461 - 11490 of 12690

Full-Text Articles in Physical Sciences and Mathematics

Small Signal Analysis For Dc Bus Voltage Disturbance Resistance Of Voltage Source Converter, Yingjie Wang, Xiaojie Wu, Ping Lu, Yonglei Zhang Jan 2016

Small Signal Analysis For Dc Bus Voltage Disturbance Resistance Of Voltage Source Converter, Yingjie Wang, Xiaojie Wu, Ping Lu, Yonglei Zhang

Turkish Journal of Electrical Engineering and Computer Sciences

The DC bus voltage of the voltage source converter (VSC) is prone to large fluctuation and even to losing its stability for the large mutation of grid voltage or DC-link loads. First the characteristics of two-step transmission to power in the VSC are analyzed, proving that it is inevitable for DC bus voltage fluctuation to occur when grid voltage or DC-link loads mutate. A new two-step feedforward control strategy is then put forward for curbing the fluctuation, which overcomes the shortcoming by which the traditional feedforward control strategy is affected for the performance of current control. The small signal models …

Go to article

Behavior-Based Detection Of Application Layer Distributed Denial Of Service Attacks During Flash Events, Renukadevi Saravanan, Saraswathi Shanmuganathan, Yogesh Palanichamy Jan 2016

Behavior-Based Detection Of Application Layer Distributed Denial Of Service Attacks During Flash Events, Renukadevi Saravanan, Saraswathi Shanmuganathan, Yogesh Palanichamy

Turkish Journal of Electrical Engineering and Computer Sciences

Distributed denial of service (DDoS) attacks are ever threatening to the developers and users of the Internet. DDoS attacks targeted at the application layer are especially difficult to be detected since they mimic the legitimate users' requests. The situation becomes more serious when they occur during flash events. A more sophisticated algorithm is required to detect such attacks during a flash crowd. A few existing works make use of flow similarity for differentiating flash crowds and DDoS, but flow characteristics alone cannot be used for effective detection. In this paper, we propose a novel mechanism for discriminating DDoS and flash …

Go to article

Feature Selection For Movie Recommendation, Zehra Çataltepe, Mahi̇ye Uluyağmur, Esengül Tayfur Jan 2016

Feature Selection For Movie Recommendation, Zehra Çataltepe, Mahi̇ye Uluyağmur, Esengül Tayfur

Turkish Journal of Electrical Engineering and Computer Sciences

TV users have an abundance of different movies they could choose from, and with the quantity and quality of data available both on user behavior and content, better recommenders are possible. In this paper, we evaluate and combine different content-based and collaborative recommendation methods for a Turkish movie recommendation system. Our recommendation methods can make use of user behavior, different types of content features, and other users' behavior to predict movie ratings. We gather different types of data on movies, such as the description, actors, directors, year, and genre. We use natural language processing methods to convert the Turkish movie …

Go to article

Design And Implementation Of A Man-Overboard Emergency Discovery System Based On Wireless Sensor Networks, Abdullah Sevi̇n, Cüneyt Bayilmiş, İsmai̇l Ertürk, Hüseyi̇n Eki̇z, Ahmet Karaca Jan 2016

Design And Implementation Of A Man-Overboard Emergency Discovery System Based On Wireless Sensor Networks, Abdullah Sevi̇n, Cüneyt Bayilmiş, İsmai̇l Ertürk, Hüseyi̇n Eki̇z, Ahmet Karaca

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, wireless sensor networks (WSNs) have been widely employed in many different fields such as military, surveillance, health, agricultural, automation, and environmental monitoring. This paper presents a designed and implemented WSN-based man-overboard emergency discovery system, abbreviated as W-MEDS, that discovers the location of a person in emergency circumstances and runs an alarm system on a ship. The developed W-MEDS carries out a fast man-overboard (MOB) discovery and initiates the vital rescue procedure. It mainly consists of a WSN and a control and discovery system. When a MOB accident occurs, this situation is easily detected through the WSN nodes capable of …

Go to article

Economic Assessment Of A Hybrid Turboexpander-Fuel Cell Gas Energy Extraction Plant, Ahmad Darabi, Ahmad Shariati, Reza Ghanaee, Ali Soleimani Jan 2016

Economic Assessment Of A Hybrid Turboexpander-Fuel Cell Gas Energy Extraction Plant, Ahmad Darabi, Ahmad Shariati, Reza Ghanaee, Ali Soleimani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a hybrid turboexpander-fuel cell (TE-FC) is investigated for extraction of electrical energy from high pressure gas in which the fuel cells are used for preheating the gas. Combination of expanders and fuel cells will reduce the fuel consumption and greenhouse gas emission. This study reveals that there are some circumstances in which the use of fuel cells in conjunction with a turboexpander is not recommended from an economic point of view. This paper seeks the region in which utilization of fuel cells along with a turboexpander presents maximum economic profit. Using the strategy provided in this paper …

Go to article

A Mapreduce-Based Distributed Svm Algorithm For Binary Classification, Ferhat Özgür Çatak, Mehmet Erdal Balaban Jan 2016

A Mapreduce-Based Distributed Svm Algorithm For Binary Classification, Ferhat Özgür Çatak, Mehmet Erdal Balaban

Turkish Journal of Electrical Engineering and Computer Sciences

Although the support vector machine (SVM) algorithm has a high generalization property for classifying unseen examples after the training phase~and a small loss value, the algorithm is not suitable for real-life classification and regression problems. SVMs cannot solve hundreds of thousands of examples in a training dataset. In previous studies on distributed machine-learning algorithms, the SVM was trained in a costly and preconfigured computer environment. In this research, we present a MapReduce-based distributed parallel SVM training algorithm for binary classification problems. This work shows how to distribute optimization problems over cloud computing systems with the MapReduce technique. In the second …

Go to article

Quantitative Information Extraction From Gas Sensor Data Using Principal Component Regression, Ahmet Özmen, Beki̇r Mumyakmaz, Mehmet Ali̇ Ebeoğlu, Ci̇hat Taşaltin, İlke Gürol, Zafer Zi̇ya Öztürk, Deni̇z Dural Jan 2016

Quantitative Information Extraction From Gas Sensor Data Using Principal Component Regression, Ahmet Özmen, Beki̇r Mumyakmaz, Mehmet Ali̇ Ebeoğlu, Ci̇hat Taşaltin, İlke Gürol, Zafer Zi̇ya Öztürk, Deni̇z Dural

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel use of the principal component analysis (PCA) and regression methods for quantitative feature extraction from gas sensor data. In this approach, PCA plots are interpreted by observing the locations of samples in the principal component domain. A trainable data processing system that also produces numerical output is designed to validate the method. The main advantages of this system are: 1) retrainability: once it is trained, it can be used for any gas set; 2) flexibility: adaptation to different targets does not require hardware modifications (if a sufficient number and variety of sensors are installed in …

Go to article

A Generalized Design Method For Multifunction Converters Used In A Photovoltaic System, Trung Nhan Nguyen, An Luo Jan 2016

A Generalized Design Method For Multifunction Converters Used In A Photovoltaic System, Trung Nhan Nguyen, An Luo

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a general design method for multifunction converters using photovoltaic systems is proposed. With the proposed converter, the photovoltaic generator can provide flexibility, accuracy, and fast responses in both harmonic suppression and power injection modes in all cases of the grid-connected load. The controller for the proposed converter is designed based on the Lyapunov technique, along with the generalized algorithm for determining the global optimal values of the stability bounds. Therefore, the proposed converter can perform accurately and efficiently in the case of fixed system parameters as well as in the case of varying system parameters. Simulations and …

Go to article

Performance Analysis Of Biogeography-Based Optimization For Automatic Voltage Regulator System, Uğur Güvenç, Ali̇ Hakan Işik, Tuncay Yi̇ği̇t, İbrahi̇m Akkaya Jan 2016

Performance Analysis Of Biogeography-Based Optimization For Automatic Voltage Regulator System, Uğur Güvenç, Ali̇ Hakan Işik, Tuncay Yi̇ği̇t, İbrahi̇m Akkaya

Turkish Journal of Electrical Engineering and Computer Sciences

A self-tuning method to determine the appropriate parameters of a proportional-integral-derivative controller for an automatic voltage regulator (AVR) system using a biogeography-based optimization (BBO) algorithm is proposed in this study. The BBO algorithm was developed based on the theory of biogeography, which describes migration and its results. We propose that the BBO algorithm has a high-quality solution and stable convergence characteristics, and thus it improves the transient response of the controlled system. The performance of the BBO algorithm depends on the transient response, root locus, and Bode analysis. Robustness analysis is done in the AVR system, which is tuned by …

Go to article

Site-Specific Design Optimization Of Horizontal-Axis Wind Turbine Systems Using Pso Algorithm, Ulaş Emi̇noğlu Jan 2016

Site-Specific Design Optimization Of Horizontal-Axis Wind Turbine Systems Using Pso Algorithm, Ulaş Emi̇noğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Due to the complexity of wind turbine systems (WTSs) containing multiple components, design parameters of a WTS must match each other in order to produce electrical energy at a lower cost and a higher efficiency. In this study, a framework for site-specific design optimization of a horizontal-axis WTS is proposed. It is based on cost reduction and the objective function is the produced energy cost. The cost of energy model proposed by the National Renewable Energy Laboratory is utilized. In order to compute turbine output power that results in annual energy production, a new approach is proposed to model the …

Go to article

An Advanced Optimization Technique For Considering Reliability Issues And Unit Commitment Problems Simultaneously, Ahmad Heidari, Mohammad Reza Alizadeh Pahlavani, Hamid Dehghani Jan 2016

An Advanced Optimization Technique For Considering Reliability Issues And Unit Commitment Problems Simultaneously, Ahmad Heidari, Mohammad Reza Alizadeh Pahlavani, Hamid Dehghani

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an advanced optimization technique to solve unit commitment problems and reliability issues simultaneously for thermal generating units. To solve unit commitment, generalized Benders decomposition along with a genetic algorithm are proposed to include minimum up/down time constraints, and for reliability issues consideration, a fuzzy stochastic-based technique is presented. To implement the problem into an optimization program, MATLAB software and CPLEX and KNITRO solvers are applied. To verify the proposed technique and algorithm, two case studies, the IEEE 14- and 118-bus systems, are implemented for optimal generation scheduling and reliability issues. Finally, a comparison with other solution techniques …

Go to article

An Unsupervised Heterogeneous Log-Based Framework For Anomaly Detection, Asif Iqbal Hajamydeen, Nur Izura Udzir, Ramlan Mahmod, Abdul Azim Abdul Ghani Jan 2016

An Unsupervised Heterogeneous Log-Based Framework For Anomaly Detection, Asif Iqbal Hajamydeen, Nur Izura Udzir, Ramlan Mahmod, Abdul Azim Abdul Ghani

Turkish Journal of Electrical Engineering and Computer Sciences

Log analysis is a method to identify intrusions at the host or network level by scrutinizing the log events recorded by the operating systems, applications, and devices. Most work contemplates a single type of log for analysis, leading to an unclear picture of the situation and difficulty in deciding the existence of an intrusion. Moreover, most existing detection methods are knowledge-dependent, i.e. using either the characteristics of an anomaly or the baseline of normal traffic behavior, which limits the detection process to only anomalies based on the acquired knowledge. To discover a wide range of anomalies by scrutinizing various logs, …

Go to article

Grid-Connected Induction Generator Interturn Fault Analysis Using A Pca-Ann-Based Algorithm, Haydar Bayar, Ümi̇t Kemaletti̇n Terzi̇ Jan 2016

Grid-Connected Induction Generator Interturn Fault Analysis Using A Pca-Ann-Based Algorithm, Haydar Bayar, Ümi̇t Kemaletti̇n Terzi̇

Turkish Journal of Electrical Engineering and Computer Sciences

It is difficult for short circuits among the internal windings of one phase in electrical machines to be determined in a reliable and speedy manner. The failure currents that occur, especially in short circuits with a few windings, are at such low levels that they cannot be determined by relay systems. This results in growing faults and damage. In this study, we designed a model that can define winding failures successfully at very small levels by using the PCA and ANN algorithms. We tested the real-time faults and measured the system performance with the installed test rig. The developed protection …

Go to article

Source Detection And Propagation Of Equal Frequency Voltage Flicker In Nonradial Power System, Abdolmajid Dejamkhooy, Ali Dastfan, Alireza Ahmadyfard Jan 2016

Source Detection And Propagation Of Equal Frequency Voltage Flicker In Nonradial Power System, Abdolmajid Dejamkhooy, Ali Dastfan, Alireza Ahmadyfard

Turkish Journal of Electrical Engineering and Computer Sciences

Nowadays electric power quality problems such as flicker (voltage fluctuation) are major concerns of electric companies and industrial consumers. Identification of flicker sources is an important stage in the flicker reduction process. Flicker source can be modeled as a nonlinear load whose admittance is intermittent and time-variant. In the steady state, fluctuation of voltage amplitude is a function of the impedance of flicker sources. In this paper, after calculating the gradient of voltage amplitudes and constructing a Jacobian matrix, criteria for flicker source detection are proposed. Therefore, by measuring voltage and current of each load in the power system, the …

Go to article

The Process Of Creeping Discharge-Caused Damage On Oil/Pressboard Insulation, Ruijin Liao, Ende Hu, Lijun Yang, Lian Duan Jan 2016

The Process Of Creeping Discharge-Caused Damage On Oil/Pressboard Insulation, Ruijin Liao, Ende Hu, Lijun Yang, Lian Duan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents experimental research on creeping discharge by using cylinder-plate electrode configurations under AC voltages. The process of creeping discharge-caused damage on the oil/pressboard insulation was studied. First, the electric field distribution was achieved by Multiphysics software simulation. Afterwards, the phenomena that occurred in the entire damage process, such as ``white smoke'', ``white mark'', and ``black mark'', were recorded and analyzed. Furthermore, the micromorphology of the oil-impregnated pressboard was observed via scanning electron microscope (SEM). Finally, the inner mechanism of the damage to the oil/pressboard insulation was explored according to the phenomena and the SEM morphologies. Results showed that …

Go to article

A New Single Stage Single Phase Power Factor Corrected And Isolated Ac-Dc Converter Based On Resonance And Soft Switching, Haci Bodur, Erdem Akboy, İsmai̇l Aksoy Jan 2016

A New Single Stage Single Phase Power Factor Corrected And Isolated Ac-Dc Converter Based On Resonance And Soft Switching, Haci Bodur, Erdem Akboy, İsmai̇l Aksoy

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new single stage single phase power factor corrected and isolated AC-DC converter based on resonance and soft switching (SS) is presented. In fact, a new concept for power factor corrected converter is proposed in this study. This converter provides power factor correction (PFC) by using a switch and a fully resonant circuit. It also provides regulated and isolated output voltage with direct power transfer by using a second switch and forward and flyback topologies based on resonance. Both switches in the converter are controlled with the same closed loop and the time multiplexing, and are switched …

Go to article

Comparative Study Of Drive Systems Using Vector-Controlled Pmsm Fed By A Matrix Converter And A Conventional Frequency Converter, Pawel Szczesniak, Konrad Urbanski, Zbigniew Fedyczak, Krzysztof Zawirski Jan 2016

Comparative Study Of Drive Systems Using Vector-Controlled Pmsm Fed By A Matrix Converter And A Conventional Frequency Converter, Pawel Szczesniak, Konrad Urbanski, Zbigniew Fedyczak, Krzysztof Zawirski

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a comparative study of a drive system with a permanent magnet synchronous motor fed by a matrix converter and a voltage source inverter with diode rectifier stage. A rotor-oriented vector control is implemented in the drive control. Space vector modulation techniques are used for both converters in the output current modulation process. Initial simulation test results and comparison are presented. The advantages of both solutions are indicated. Special attention is given to the drive control in the low speed range. The main aim of this article is to present drive systems with a matrix converter as an …

Go to article

Online Monitoring And Accident Diagnosis Aid System For The Nur Nuclear Research Reactor, Amina Nasrine Allalou, Mohamed Tadjine, Mohamed Seghir Boucherit Jan 2016

Online Monitoring And Accident Diagnosis Aid System For The Nur Nuclear Research Reactor, Amina Nasrine Allalou, Mohamed Tadjine, Mohamed Seghir Boucherit

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the design of a computerized monitoring and diagnosis aid system (CMDAS) for the Nur Nuclear Research Reactor based on real-time plant-specific safety parameters. The CMDAS carries out early detection and identification of accidents that might affect this reactor using supervised neural networks. The graphical programming language LabVIEW is used for creating a human--operator interface, networking, embedding the diagnosis procedure, and handling and storing the data. The methodology presented in this paper can be adapted for any nuclear research reactor.

Go to article

Multiple Perspectives On The Hardware Implementations Of Biological Neuron Models And Programmable Design Aspects, Ni̇met Korkmaz, İsmai̇l Öztürk, Recai̇ Kiliç Jan 2016

Multiple Perspectives On The Hardware Implementations Of Biological Neuron Models And Programmable Design Aspects, Ni̇met Korkmaz, İsmai̇l Öztürk, Recai̇ Kiliç

Turkish Journal of Electrical Engineering and Computer Sciences

A few individual design examples of programmable device-based biological neuron model implementations are available in the literature, but there is no comprehensive study that examines analog and digital programmable design examples of frequently studied biological neuron model implementations. The aim of this paper is to present a comparative study about programmable and reconfigurable implementations of the FitzHugh--Nagumo, Izhikevich, and Hindmarsh--Rose neuron models. Since field programmable analog array (FPAA) and field programmable gate array (FPGA) devices offer several advantages such as flexible design possibilities, reduction of the complexity of design, real-time modification, and software control for programmable and reconfigurable implementations of …

Go to article

Scale Invariant And Fixed-Length Feature Extraction By Integrating Discrete Cosine Transform And Autoregressive Signal Modeling For Palmprint Identification, Burhan Ergen Jan 2016

Scale Invariant And Fixed-Length Feature Extraction By Integrating Discrete Cosine Transform And Autoregressive Signal Modeling For Palmprint Identification, Burhan Ergen

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, the need for automatic identification has caused researchers to focus on biometric identification methods. Palmprint-based biometric identification has several advantages such as user friendliness, low-cost capturing devices, and robustness. In this paper, a method that integrates the discrete cosine transform (DCT) and an autoregressive (AR) signal modeling is proposed for biometric identification. The method provides scale invariance and produces a fixed-length feature vector. In particular, the Burg algorithm is used for the determination of the AR parameters used as a feature vector. Experimental results demonstrate that a small number of the AR parameters that are modeling the DCT coefficients …

Go to article

Improved Direct Power Control For 3-Level Ac/Dc Converter Under Unbalanced And/Or Distorted Voltage Source Conditions, Imad Merzouk, Mohamed Lokmane Bendaas Jan 2016

Improved Direct Power Control For 3-Level Ac/Dc Converter Under Unbalanced And/Or Distorted Voltage Source Conditions, Imad Merzouk, Mohamed Lokmane Bendaas

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an improved direct power control with space vector modulation for a 3-phase 3-level neutral point clamped converter supplied by unbalanced and/or distorted grid voltage is proposed. The main objective of the control scheme is to obtain balanced and sinusoidal input current with unity power factor under nonideal voltage supply. To achieve the control objectives, compensated active and reactive powers are calculated and added to the referencing one. A theoretical analysis of active and reactive power under a nonideal source is clearly demonstrated. In order to calculate the compensated powers, the extraction of positive, negative, and harmonic sequences …

Go to article

Identifying Acquisition Devices From Recorded Speech Signals Using Wavelet-Based Features, Ömer Eski̇dere Jan 2016

Identifying Acquisition Devices From Recorded Speech Signals Using Wavelet-Based Features, Ömer Eski̇dere

Turkish Journal of Electrical Engineering and Computer Sciences

Speech characteristics have played a critical role in media forensics, particularly in the investigation of evidence. This study proposes two wavelet-based feature extraction methods for the identification of acquisition devices from recorded speech. These methods are discrete wavelet-based coefficients (DWBCs) and wavelet packet-based coefficients, which are mainly based on a multiresolution analysis. These features' ability to capture characteristics of acquisition devices is compared to conventional mel frequency cepstral coefficients and subband-based coefficients. In the experiments, 14 different audio acquisition devices were trained and tested using support vector machines. Experimental results showed that DWBCs can effectively be used in source audio …

Go to article

Performance Evaluation Of A New Efficient H.264 Intraprediction Scheme, Sara Hamdy, Mostafa Ibrahim, Mohamed Osman Jan 2016

Performance Evaluation Of A New Efficient H.264 Intraprediction Scheme, Sara Hamdy, Mostafa Ibrahim, Mohamed Osman

Turkish Journal of Electrical Engineering and Computer Sciences

The paper presents a new efficient H.264/AVC$ 4 \times 4$ intraprediction scheme. The new prediction scheme is based on the best prediction matrix mode. The main idea behind the new prediction scheme is to combine the most usable intraprediction modes, {vertical - horizontal - DC} , into a new efficient prediction mode. The new prediction scheme is implemented using VHDL and hence it uses the full advantages of inherent parallelism in the hardware. We evaluate the performance of this prediction scheme in terms of compression ratio, peak signal to noise ratio, and bit rate using seven video sequences. Moreover, we …

Go to article

Disaster Prevention Literacy Among School Administrators And Teachers: A Study On The Plan For Disaster Prevention And Campus Network Deployment And Experiment In Taiwan, Sung-Chin Chung, Cherng-Jyh Yen Jan 2016

Disaster Prevention Literacy Among School Administrators And Teachers: A Study On The Plan For Disaster Prevention And Campus Network Deployment And Experiment In Taiwan, Sung-Chin Chung, Cherng-Jyh Yen

Educational Leadership & Workforce Development Faculty Publications

Taiwan is located at the high-risk region of natural disasters with the frequently occurred earthquakes. The importance of the disaster prevention education on campus is made even more obvious by the fact that natural disasters often occur during the school days. Given the leading roles the school administrators and teachers playing in the disaster prevention education of their pupils, this study purposed to investigate how disaster prevention literacy was among them and how disaster prevention literacy differed across various background variables of them. Furthermore, the current study also examined if disaster prevention literacy changed by participation in the disaster prevention …

Go to article

A Hybrid Parallel Delaunay Image-To-Mesh Conversion Algorithm Scalable On Distributed-Memory Clusters, Daming Feng, Andrey N. Chernikov, Nikos Chrisochoides Jan 2016

A Hybrid Parallel Delaunay Image-To-Mesh Conversion Algorithm Scalable On Distributed-Memory Clusters, Daming Feng, Andrey N. Chernikov, Nikos Chrisochoides

Computer Science Faculty Publications

In this paper, we present a scalable three dimensional hybrid MPI+Threads parallel Delaunay image-to-mesh conversion algorithm. A nested master-worker communication model for parallel mesh generation is implemented which simultaneously explores process-level parallelization and thread-level parallelization: inter-node communication using MPI and inter-core communication inside one node using threads. In order to overlap the communication (task request and data movement) and computation (parallel mesh refinement), the inter-node MPI communication and intra-node local mesh refinement is separated. The master thread that initializes the MPI environment is in charge of the inter-node MPI communication while the worker threads of each process are only responsible …

Go to article

Audience Segmentation For Campaign Design: Addressing Climate Change In Singapore, Benjamin H. Detenber, Sonny Rosenthal, Youqing Liao, Shirley S. Ho Jan 2016

Audience Segmentation For Campaign Design: Addressing Climate Change In Singapore, Benjamin H. Detenber, Sonny Rosenthal, Youqing Liao, Shirley S. Ho

Research Collection College of Integrative Studies

A nationally representative telephone survey (n = 1,006) was conducted to understand how different groups of Singaporeans regard the issue of climate change and their inclination toward action in dealing with it. We measured attitudes, knowledge, and perceptions of the problem of climate change and the role of various stakeholders in addressing it. The data were subjected to a latent class analysis to produce three distinctive segments of the population: the concerned, the disengaged, and the passive. These segments stand in contrast to those discovered in the United States, Australia, Germany, and India and suggest different strategies for public engagement …

Go to article

Press: Personalized Event Scheduling Recommender System (Demonstration), Hoong Chuin Lau, Aldy Gunawan, Pradeep Varakantham, Wenjie Wang Jan 2016

Press: Personalized Event Scheduling Recommender System (Demonstration), Hoong Chuin Lau, Aldy Gunawan, Pradeep Varakantham, Wenjie Wang

Research Collection School Of Computing and Information Systems

This paper presents a personalized event scheduling recom-mender system, PRESS, for a large conference setting with multiple parallel tracks. PRESS is a mobile application that gathers personalized information from a user and recommends talks/demos to be attend. The input from a user include a list of keyword preferences and (optionally) preferred talks. We use the MALLET topic model package to analyze the set of conference papers and classify them based on automatically identified topics. We propose an algorithm to generate a list of recommended papers based on the user keywords and the MALLET topics. An optimization model is then applied …

Go to article

Data Analytics On Consumer Behavior In Omni-Channel Retail Banking, Card And Payment Services, Geng Dan Jan 2016

Data Analytics On Consumer Behavior In Omni-Channel Retail Banking, Card And Payment Services, Geng Dan

Research Collection School Of Computing and Information Systems

Innovations in financial services have created challenges for banks that Information Systems (IS) research can address. My interests involve transaction cost theory, substitution and complementarity theory, and consumer informedness theory to understand consumer behavior and firm performance in the omni-channel world of digital banking. At a high level, my research inquiry asks: How can financial institutions take advantage of the deep insights that data analytics and management science modeling create on consumer behavior and channel management decision-making? And how can changes in payments and services in retail banking be understood in spatial and temporal terms? I am working on three …

Go to article

Online Arima Algorithms For Time Series Prediction, Chenghao Liu, Hoi, Steven C. H., Peilin Zhao, Jianling Sun Jan 2016

Online Arima Algorithms For Time Series Prediction, Chenghao Liu, Hoi, Steven C. H., Peilin Zhao, Jianling Sun

Research Collection School Of Computing and Information Systems

Autoregressive integrated moving average (ARIMA) is one of the most popular linear models for time series forecasting due to its nice statistical properties and great flexibility. However, its parameters are estimated in a batch manner and its noise terms are often assumed to be strictly bounded, which restricts its applications and makes it inefficient for handling large-scale real data. In this paper, we propose online learning algorithms for estimating ARIMA models under relaxed assumptions on the noise terms, which is suitable to a wider range of applications and enjoys high computational efficiency. The idea of our ARIMA method is to …

Go to article

Top-K Dominating Queries On Incomplete Data, Xiaoye Miao, Yunjun Gao, Baihua Zheng, Gang Chen, Huiyong Cui Jan 2016

Top-K Dominating Queries On Incomplete Data, Xiaoye Miao, Yunjun Gao, Baihua Zheng, Gang Chen, Huiyong Cui

Research Collection School Of Computing and Information Systems

The top-k dominating (TKD) query returns the k objects that dominate the maximum number of objects in a given dataset. It combines the advantages of skyline and top-k queries, and plays an important role in many decision support applications. Incomplete data exists in a wide spectrum of real datasets, due to device failure, privacy preservation, data loss, and so on. In this paper, for the first time, we carry out a systematic study of TKD queries on incomplete data, which involves the data having some missing dimensional value(s). We formalize this problem, and propose a suite of efficient algorithms for …

Go to article

First Prev Next Last