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Towards Formal Modelling And Verification Of Pervasive Computing Systems, Yan Liu, Xian Zhang, Yang Liu, Jin Song Dong, Jun Sun, Jit Biswas, Mounir Mokhtari Jan 2014

Towards Formal Modelling And Verification Of Pervasive Computing Systems, Yan Liu, Xian Zhang, Yang Liu, Jin Song Dong, Jun Sun, Jit Biswas, Mounir Mokhtari

Research Collection School Of Computing and Information Systems

Smart systems equipped with emerging pervasive computing technologies enable people with limitations to live in their homes independently. However, lack of guarantees for correctness prevent such system to be widely used. Analysing the system with regard to correctness requirements is a challenging task due to the complexity of the system and its various unpredictable faults. In this work, we propose to use formal methods to analyse pervasive computing (PvC) systems. Firstly, a formal modelling framework is proposed to cover the main characteristics of such systems (e.g., context-awareness, concurrent communications, layered architectures). Secondly, we identify the safety requirements (e.g., free of …


Learning Assumptions For Compositional Verification Of Timed Systems, Shang-Wei Lin Lin, Yang Liu, Jun Sun, Jun Sun Jan 2014

Learning Assumptions For Compositional Verification Of Timed Systems, Shang-Wei Lin Lin, Yang Liu, Jun Sun, Jun Sun

Research Collection School Of Computing and Information Systems

Compositional techniques such as assume-guarantee reasoning (AGR) can help to alleviate the state space explosion problem associated with model checking. However, compositional verification is difficult to be automated, especially for timed systems, because constructing appropriate assumptions for AGR usually requires human creativity and experience. To automate compositional verification of timed systems, we propose a compositional verification framework using a learning algorithm for automatic construction of timed assumptions for AGR. We prove the correctness and termination of the proposed learning-based framework, and experimental results show that our method performs significantly better than traditional monolithic timed model checking.


Sherlock: Microenvironment Sensing For Smartphones, Zheng Yang, Longfei Shangguan, Weixi Gu, Zimu Zhou, Chenshu Wu, Yunhao Liu Jan 2014

Sherlock: Microenvironment Sensing For Smartphones, Zheng Yang, Longfei Shangguan, Weixi Gu, Zimu Zhou, Chenshu Wu, Yunhao Liu

Research Collection School Of Computing and Information Systems

Context-awareness is getting increasingly important for a range of mobile and pervasive applications on nowadays smartphones. Whereas human-centric contexts (e.g., indoor/ outdoor, at home/in office, driving/walking) have been extensively researched, few attempts have studied from phones’ perspective (e.g., on table/sofa, in pocket/bag/hand). We refer to such immediate surroundings as micro-environment, usually several to a dozen of centimeters, around a phone. In this study, we design and implement Sherlock, a micro-environment sensing platform that automatically records sensor hints and characterizes the micro-environment of smartphones. The platform runs as a daemon process on a smartphone and provides finer-grained environment information to upper …


Loki: A Privacy-Conscious Platform For Crowdsourced Surveys, Thivya Kandappu, Vijay Sivaraman, Arik Friedman, Roksana Boreli Jan 2014

Loki: A Privacy-Conscious Platform For Crowdsourced Surveys, Thivya Kandappu, Vijay Sivaraman, Arik Friedman, Roksana Boreli

Research Collection School Of Computing and Information Systems

Emerging platforms such as Amazon Mechanical Turk and Google Consumer Surveys are increasingly being used by researchers and market analysts to crowdsource large-scale survey data from on-line populations at extremely low-cost. However, by participating in successive surveys, users risk being profiled and targeted, both by surveyors and by the platform itself. In this paper we propose, develop, and evaluate the design of a crowdsourcing platform, called Loki, that is privacy conscious. Our contributions are three-fold: (a) We propose Loki, a system that allows users to obfuscate their (ratings-based or multiple-choice) responses at-source based on their chosen privacy level, and gives …


Wenzher: Comprehensive Vertical Search For Healthcare Domain, Liqiang Nie, Tao Li, Mohammad Akbari, Jialie Shen, Tat-Seng Chua Jan 2014

Wenzher: Comprehensive Vertical Search For Healthcare Domain, Liqiang Nie, Tao Li, Mohammad Akbari, Jialie Shen, Tat-Seng Chua

Research Collection School Of Computing and Information Systems

Online health seeking has transformed the way of health knowledge exchange and reusability. The existing general and vertical health search engines, however, just routinely return lists of matched documents or question answer (QA) pairs, which may overwhelm the seekers or not sufficiently meet the seekers’ expectations. Instead, our multilingual system is able to return one multi-faceted answer that is well-structured and precisely extracted from multiple heterogeneous healthcare sources. Further, should the seekers not be satisfied with the returned search results, our system can automatically route the unsolved questions to the professionals with relevant expertise


Strategic Decision Support System Using Heuristic Algorithm For Practical Outlet Zones Allocation To Dealers In A Beer Supply Distribution Network, Michelle Lee Fong Cheong Jan 2014

Strategic Decision Support System Using Heuristic Algorithm For Practical Outlet Zones Allocation To Dealers In A Beer Supply Distribution Network, Michelle Lee Fong Cheong

Research Collection School Of Computing and Information Systems

We consider a two-echelon beer supply distribution network with the brewer replenishing the dealers and the dealers serving the outlet zones directly, for multiple product types. The allocation of the outlet zones to the dealers will determine the quantity of products the brewer replenishes each dealer, which will in turn impact the total warehousing and transportation costs. The non-linear optimization model formulated is difficult to solve to optimality, and the model itself does not include practical business considerations in the distribution business. A heuristics algorithm is designed and easily implemented using spreadsheets with Visual Basic programming to effectively and efficiently …


Measuring And Modelling The Thermal Performance Of The Tamar Suspension Bridge Using A Wireless Sensor Network, Nicholas De Battista, James M. W. Brownjohn, Hwee-Pink Tan, Ki Young Koo Jan 2014

Measuring And Modelling The Thermal Performance Of The Tamar Suspension Bridge Using A Wireless Sensor Network, Nicholas De Battista, James M. W. Brownjohn, Hwee-Pink Tan, Ki Young Koo

Research Collection School Of Computing and Information Systems

A study on the thermal performance of the Tamar Suspension Bridge deck in Plymouth, UK, is presented in this paper. Ambient air, suspension cable, deck and truss temperatures were acquired using a wired sensor system. Deck extension data were acquired using a two-hop wireless sensor network. Empirical models relating the deck extension to various combinations of temperatures were derived and compared. The most accurate model, which used all the four temperature variables, predicted the deck extension with an accuracy of 99.4%. Time delays ranging from 10 to 66 min were identified between the daily cycles of the air temperature and …


Free Market Of Crowdsourcing: Incentive Mechanism Design For Mobile Sensing, Xinglin Zhang, Zheng Yang, Zimu Zhou, Haibin Cai, Lei Chen, Xiang-Yang Li Jan 2014

Free Market Of Crowdsourcing: Incentive Mechanism Design For Mobile Sensing, Xinglin Zhang, Zheng Yang, Zimu Zhou, Haibin Cai, Lei Chen, Xiang-Yang Li

Research Collection School Of Computing and Information Systems

Off-the-shelf smartphones have boosted large scale participatory sensing applications as they are equipped with various functional sensors, possess powerful computation and communication capabilities, and proliferate at a breathtaking pace. Yet the low participation level of smartphone users due to various resource consumptions, such as time and power, remains a hurdle that prevents the enjoyment brought by sensing applications. Recently, some researchers have done pioneer works in motivating users to contribute their resources by designing incentive mechanisms, which are able to provide certain rewards for participation. However, none of these works considered smartphone users’ nature of opportunistically occurring in the area …


Free Market Of Crowdsourcing: Incentive Mechanism Design For Mobile Sensing, Xinglin Zhang, Zheng Yang, Zimu Zhou, Haibin Cai, Lei Chen, Xiang-Yang Li Jan 2014

Free Market Of Crowdsourcing: Incentive Mechanism Design For Mobile Sensing, Xinglin Zhang, Zheng Yang, Zimu Zhou, Haibin Cai, Lei Chen, Xiang-Yang Li

Research Collection School Of Computing and Information Systems

Off-the-shelf smartphones have boosted large scale participatory sensing applications as they are equipped with various functional sensors, possess powerful computation and communication capabilities, and proliferate at a breathtaking pace. Yet the low participation level of smartphone users due to various resource consumptions, such as time and power, remains a hurdle that prevents the enjoyment brought by sensing applications. Recently, some researchers have done pioneer works in motivating users to contribute their resources by designing incentive mechanisms, which are able to provide certain rewards for participation. However, none of these works considered smartphone users’ nature of opportunistically occurring in the area …


Complexity Of The Soundness Problem Of Workflow Nets, Guan Jun Liu, Jun Sun, Yang Liu, Jin Song Dong Jan 2014

Complexity Of The Soundness Problem Of Workflow Nets, Guan Jun Liu, Jun Sun, Yang Liu, Jin Song Dong

Research Collection School Of Computing and Information Systems

Classical workflow nets (WF-nets for short) are an important subclass of Petri nets that are widely used to model and analyze workflow systems. Soundness is a crucial property of workflow systems and guarantees that these systems are deadlock-free and bounded. Aalst et al. proved that the soundness problem is decidable for WF-nets and can be polynomially solvable for free-choice WF-nets. This paper proves that the soundness problem is PSPACE-hard for WF-nets. Furthermore, it is proven that the soundness problem is PSPACE-complete for bounded WF-nets. Based on the above conclusion, it is derived that the soundness problem is also PSPACE-complete for …


The Challenge Of Continuous Mobile Context Sensing, Rajesh Krishna Balan, Youngki Lee, Kiat Wee Tan, Archan Misra Jan 2014

The Challenge Of Continuous Mobile Context Sensing, Rajesh Krishna Balan, Youngki Lee, Kiat Wee Tan, Archan Misra

Research Collection School Of Computing and Information Systems

In this paper, we highlight the challenge of continuously sensing context data from mobile phones. In particular, we show that the energy cost of this type of continuous sensing is extremely high if a) accuracy is desired, and b) power optimisations do not work well if multiple tasks are sensing concurrently. Our results are derived from our experience in building the LiveLabs context sensing platform. We present results for different types of sensing tasks; ranging from simple sensing using just one sensor all the way to multi-sensor sensing performed by concurrent high-level tasks. We end with a discussion of the …


Privacy-Preserving Ad-Hoc Equi-Join On Outsourced Data, Hwee Hwa Pang, Xuhua Ding Jan 2014

Privacy-Preserving Ad-Hoc Equi-Join On Outsourced Data, Hwee Hwa Pang, Xuhua Ding

Research Collection School Of Computing and Information Systems

In IT outsourcing, a user may delegate the data storage and query processing functions to a third-party server that is not completely trusted. This gives rise to the need to safeguard the privacy of the database as well as the user queries over it. In this article, we address the problem of running ad hoc equi-join queries directly on encrypted data in such a setting. Our contribution is the first solution that achieves constant complexity per pair of records that are evaluated for the join. After formalizing the privacy requirements pertaining to the database and user queries, we introduce a …


Online Portfolio Selection: A Survey, Bin Li, Steven C. H. Hoi Jan 2014

Online Portfolio Selection: A Survey, Bin Li, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

Online portfolio selection is a fundamental problem in computational finance, which has been extensively studied across several research communities, including finance, statistics, artificial intelligence, machine learning, and data mining. This article aims to provide a comprehensive survey and a structural understanding of online portfolio selection techniques published in the literature. From an online machine learning perspective, we first formulate online portfolio selection as a sequential decision problem, and then we survey a variety of state-of-the-art approaches, which are grouped into several major categories, including benchmarks, Follow-the-Winner approaches, Follow-the-Loser approaches, Pattern-Matching--based approaches, and Meta-Learning Algorithms. In addition to the problem formulation …


Online Multiple Kernel Similarity Learning For Visual Search, Hao Xia, Chu Hong Hoi, Rong Jin, Peilin Zhao Jan 2014

Online Multiple Kernel Similarity Learning For Visual Search, Hao Xia, Chu Hong Hoi, Rong Jin, Peilin Zhao

Research Collection School Of Computing and Information Systems

Recent years have witnessed a number of studies on distance metric learning to improve visual similarity search in content-based image retrieval (CBIR). Despite their successes, most existing methods on distance metric learning are limited in two aspects. First, they usually assume the target proximity function follows the family of Mahalanobis distances, which limits their capacity of measuring similarity of complex patterns in real applications. Second, they often cannot effectively handle the similarity measure of multimodal data that may originate from multiple resources. To overcome these limitations, this paper investigates an online kernel similarity learning framework for learning kernel-based proximity functions …


Cross-Domain Password-Based Authenticated Key Exchange Revisited, Liqun Chen, Hoon Wei Lim, Guomin Yang Jan 2014

Cross-Domain Password-Based Authenticated Key Exchange Revisited, Liqun Chen, Hoon Wei Lim, Guomin Yang

Research Collection School Of Computing and Information Systems

We revisit the problem of secure cross-domain communication between two users belonging to different security domains within an open and distributed environment. Existing approaches presuppose that either the users are in possession of public key certificates issued by a trusted certificate authority (CA), or the associated domain authentication servers share a long-term secret key. In this article, we propose a generic framework for designing four-party password-based authenticated key exchange (4PAKE) protocols. Our framework takes a different approach from previous work. The users are not required to have public key certificates, but they simply reuse their login passwords, which they share …


On Empirical Validation Of Compactness Measures For Electoral Redistricting And Its Significance For Application Of Models In The Social Sciences, Christine Chou, Steven O. Kimbrough, Frederic H. Murphy, John Sullivan-Fedock, C. Jason Woodard Jan 2014

On Empirical Validation Of Compactness Measures For Electoral Redistricting And Its Significance For Application Of Models In The Social Sciences, Christine Chou, Steven O. Kimbrough, Frederic H. Murphy, John Sullivan-Fedock, C. Jason Woodard

Research Collection School Of Computing and Information Systems

Use of optimization models in science and policy applications is often problematic because the best available models are very inaccurate representations of the originating problems. Such is the case with electoral districting models, for which there exist no generally accepted measures of compactness, in spite of many proposals and much analytical study. This article reports on an experimental investigation of subjective judgments of compactness for electoral districts. The experiment draws on a unique database of 116 distinct, legally valid districting plans for the Philadelphia City Council, discovered with evolutionary computation. Subjects in the experiment displayed, in the aggregate, remarkable agreement …


Detecting Click Fraud In Online Advertising: A Data Mining Approach, Richard Oentaryo, Ee Peng Lim, Michael Finegold, David Lo, Feida Zhu, Clifton Phua, Eng-Yeow Cheu, Ghim-Eng Yap, Kelvin Sim, Kasun Perera, Bijay Neupane, Mustafa Faisal, Zeyar Aung, Wei Lee Woon, Wei Chen, Dhaval Patel, Daniel Berrar Jan 2014

Detecting Click Fraud In Online Advertising: A Data Mining Approach, Richard Oentaryo, Ee Peng Lim, Michael Finegold, David Lo, Feida Zhu, Clifton Phua, Eng-Yeow Cheu, Ghim-Eng Yap, Kelvin Sim, Kasun Perera, Bijay Neupane, Mustafa Faisal, Zeyar Aung, Wei Lee Woon, Wei Chen, Dhaval Patel, Daniel Berrar

Research Collection School Of Computing and Information Systems

Click fraud - the deliberate clicking on advertisements with no real interest on the product or service offered - is one of the most daunting problems in online advertising. Building an elective fraud detection method is thus pivotal for online advertising businesses. We organized a Fraud Detection in Mobile Advertising (FDMA) 2012 Competition, opening the opportunity for participants to work on real-world fraud data from BuzzCity Pte. Ltd., a global mobile advertising company based in Singapore. In particular, the task is to identify fraudulent publishers who generate illegitimate clicks, and distinguish them from normal publishers. The competition was held from …


Coupling Graphs, Efficient Algorithms And B-Cell Epitope Prediction, Liang Zhao, Steven C. H. Hoi, Zhenhua Li, Limsoon Wong, Hung Nguyen Jan 2014

Coupling Graphs, Efficient Algorithms And B-Cell Epitope Prediction, Liang Zhao, Steven C. H. Hoi, Zhenhua Li, Limsoon Wong, Hung Nguyen

Research Collection School Of Computing and Information Systems

Coupling graphs are newly introduced in this paper to meet many application needs particularly in the field of bioinformatics. A coupling graph is a two-layer graph complex, in which each node from one layer of the graph complex has at least one connection with the nodes in the other layer, and vice versa. The coupling graph model is sufficiently powerful to capture strong and inherent associations between subgraph pairs in complicated applications. The focus of this paper is on mining algorithms of frequent coupling subgraphs and bioinformatics application. Although existing frequent subgraph mining algorithms are competent to identify frequent subgraphs …


A Robust Smart Card-Based Anonymous User Authentication Protocol For Wireless Communications, Fengton Wen, Willy Susilo, Guomin Yang Jan 2014

A Robust Smart Card-Based Anonymous User Authentication Protocol For Wireless Communications, Fengton Wen, Willy Susilo, Guomin Yang

Research Collection School Of Computing and Information Systems

Anonymous user authentication is an important but challenging task for wireless communications. In a recent paper, Das proposed a smart cardï based anonymous user authentication protocol for wireless communications. The scheme can protect user privacy and is believed to be secure against a range of network attacks even if the secret information stored in the smart card is compromised. In this paper, we reanalyze the security of Das' scheme, and show that the scheme is in fact insecure against impersonation attacks. We then propose a new smart cardï based anonymous user authentication protocol for wireless communications. Compared with the existing …


On The Security Of Auditing Mechanisms For Secure Cloud Storage, Yong Yu, Lei Niu, Guomin Yang, Yi Mu, Willy Susilo Jan 2014

On The Security Of Auditing Mechanisms For Secure Cloud Storage, Yong Yu, Lei Niu, Guomin Yang, Yi Mu, Willy Susilo

Research Collection School Of Computing and Information Systems

Cloud computing is a novel computing model that enables convenient and on-demand access to a shared pool of configurable computing resources. Auditing services are highly essential to make sure that the data is correctly hosted in the cloud. In this paper, we investigate the active adversary attacks in three auditing mechanisms for shared data in the cloud, including two identity privacy-preserving auditing mechanisms called Oruta and Knox, and a distributed storage integrity auditing mechanism.We show that these schemes become insecure when active adversaries are involved in the cloud storage. Specifically, an active adversary can arbitrarily alter the cloud data without …


An Approach For Clone Detection In Documentation Reuse, Dmitry V. Lutsiv, Dmitry Koznov, Hamid A. Basit, Eng Lieh Ouh, Mikhail N. Smirnov, Konstantin Y. Romanovsky Jan 2014

An Approach For Clone Detection In Documentation Reuse, Dmitry V. Lutsiv, Dmitry Koznov, Hamid A. Basit, Eng Lieh Ouh, Mikhail N. Smirnov, Konstantin Y. Romanovsky

Research Collection School Of Computing and Information Systems

The paper focuses on the searching method for repetitions in DocBook/DRL or plain text documents. An algorithm has been designed based on software clone detection. The algorithm supports filtering results: clones are rejected if clone length in the group is less than 5 symbols, intersection of clone groups is eliminated, meaningfulness clones are removed, the groups containing clones consisting only of XML are eliminated. Remaining search is supported: found clones are extracted from the documentation, and clone search is repeated. One step is proved to be enough. Adaptive reuse technique of Paul Bassett – Stan Jarzabek has been implemented. A …


How Can Consumer Preferences Be Leveraged For Targeted Upselling In Cable Tv Services?, Bing Tian Dai Jan 2014

How Can Consumer Preferences Be Leveraged For Targeted Upselling In Cable Tv Services?, Bing Tian Dai

Research Collection School Of Computing and Information Systems

Internet TV has attracted a significant amount of attention from the conventional cable TV service providers, by providing customized TV programs at preferred time slots. The cable TV service providers are seeking to retain their customers by giving them a better experience: by understanding their customers’ preferences and upselling them the right products to cater to their interests. It is not easy to understand customer preferences though, since customers are not able to watch channels to which they have not subscribed. This makes it difficult to predict what they will like to watch, as a result. In this paper, I …


Innovative Applications And Security Of Internet Of Things, Yingjiu Li, Yingjiu Li, Nai-Wei Lo Jan 2014

Innovative Applications And Security Of Internet Of Things, Yingjiu Li, Yingjiu Li, Nai-Wei Lo

Research Collection School Of Computing and Information Systems

With the advances and falling cost of intelligent things like RFID/USN, sensor networks, NFC, ZigBee, smart phones, and other relevant technologies, the potential applications and implementations of Internet of things have been intensively studied by both the academia and the industry. One potential application is integrating social networks with IoT, which results in the social Internet of things (SIoT). This vision not only provides potential opportunities but also new challenges. Innovative application and security are two main issues toward this paradigm


Mini-Track Introduction: Information Economics, Competition, Regulation, Law And Society, Eric K. Clemons, Robert John Kauffman, Thomas A. Weber Jan 2014

Mini-Track Introduction: Information Economics, Competition, Regulation, Law And Society, Eric K. Clemons, Robert John Kauffman, Thomas A. Weber

Research Collection School Of Computing and Information Systems

This mini-track is informed by the most modern thinking in information economics and competitive strategy, and includes many interdisciplinary applications of IS and technology.


Evaluating Electronic Market Designs: The Effects Of Competitive Arousal And Social Facilitation On Electronic Group Buying, Yuecheng Yu, Karl R. Lang, Alex Pelaez Jan 2014

Evaluating Electronic Market Designs: The Effects Of Competitive Arousal And Social Facilitation On Electronic Group Buying, Yuecheng Yu, Karl R. Lang, Alex Pelaez

Research Collection School Of Computing and Information Systems

This article presents an evaluation approach foralternative electronic market designs and examines theimpact of competitive arousal under time pressure onmarket performance in a group-buying setting. Drawingon theory from economics, decision theory, andinformation systems, we present a competitive arousalmodel for a social buying setting that posits thatintroducing competitive arousal among buyers reducesbuyer profits and that social facilitation can mitigate thesecosts through better task completion and time tocompletion rates. Using an economic experiment, wefound that rivalry has a negative effect on buyer profitsbut also that competitive arousal increases the efficiencyof social facilitation in terms of group formation. Wediscuss the implications of these …


Inferring The Untold: Mining Software Engineering Research Publication Networks, Santonu Sarkar, Subhajit Datta Jan 2014

Inferring The Untold: Mining Software Engineering Research Publication Networks, Santonu Sarkar, Subhajit Datta

Research Collection School Of Computing and Information Systems

Since the inception of organized research publication in software engineering in 1975, the discipline has gained maturity. This journey has been guided by the synergy of ideas and interactions of individuals. In this paper, we discuss a method for aggregating the corpus of 19,000+ papers and 21,000+ authors across 16 specialized software engineering venues. We focus on the approach of data collection, processing and storage. It can be used to address questions by the software engineering research community. We evaluate three questions: patterns of research topics with time, factors influencing the contribution of individual researchers, and the interaction among the …


Running And Chasing: The Competition Between Paid Search Marketing And Search Engine Optimization, Kai Li, Mei Lin, Zhangxi Lin, Bo Xing Jan 2014

Running And Chasing: The Competition Between Paid Search Marketing And Search Engine Optimization, Kai Li, Mei Lin, Zhangxi Lin, Bo Xing

Research Collection School Of Computing and Information Systems

As search engine is leading the revenue growth in online marketing field, the competition of search engine marketing between paid search marketing (PSM) by search engine providers (SEPs), and search engine optimization (SEO) provided by search engine optimization firms, is white-hot. While PSM is simply for advertisers to buy the top ranks in sponsored links, SEO tries to optimize advertisers' websites by free-riding search engine's organic searching results. This study aims to investigate this competition by analytical modeling regarding organic search quality. We focus on sustainability conditions of SEO firms, investment analysis of SEO firms, and profit analysis of SEP. …


Risk Minimization Of Disjunctive Temporal Problem With Uncertainty, Hoong Chuin Lau, Tuan Anh Hoang Jan 2014

Risk Minimization Of Disjunctive Temporal Problem With Uncertainty, Hoong Chuin Lau, Tuan Anh Hoang

Research Collection School Of Computing and Information Systems

The Disjunctive Temporal Problem with Uncertainty (DTPU) is a fundamental problem that expresses temporal reasoning with both disjunctive constraints and contingency. A recent work (Peintner et al, 2007) develops a complete algorithm for determining Strong Controlla- bility of a DTPU. Such a notion that guarantees 100% confidence of execution may be too conservative in practice. In this paper, following the idea of (Tsamardinos 2002), we are interested to find a schedule that minimizes the risk (i.e. probability of failure) of executing a DTPU. We present a problem decomposition scheme that enables us to compute the probability of failure efficiently, followed …


Learning To Recommend Descriptive Tags For Questions In Social Forums, Liqiang Nie, Yiliang Zhao, Xiangyu Wang, Jialie Shen, Tat-Seng Chua Jan 2014

Learning To Recommend Descriptive Tags For Questions In Social Forums, Liqiang Nie, Yiliang Zhao, Xiangyu Wang, Jialie Shen, Tat-Seng Chua

Research Collection School Of Computing and Information Systems

Around 40% of the questions in the emerging social-oriented question answering forums have at most one manually labeled tag, which is caused by incomprehensive question understanding or informal tagging behaviors. The incompleteness of question tags severely hinders all the tag-based manipulations, such as feeds for topic-followers, ontological knowledge organization, and other basic statistics. This article presents a novel scheme that is able to comprehensively learn descriptive tags for each question. Extensive evaluations on a representative real-world dataset demonstrate that our scheme yields significant gains for question annotation, and more importantly, the whole process of our approach is unsupervised and can …


How Can Substitution And Complementarity Effects Be Leveraged For Broadband Internet Services Strategy?, Gwangjae Jung, Young Soo Kim, Robert J. Kauffman Jan 2014

How Can Substitution And Complementarity Effects Be Leveraged For Broadband Internet Services Strategy?, Gwangjae Jung, Young Soo Kim, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

With growth in mobile Internet services, the relationship between mobile and fixed broadband has become an issue in telecom firm strategy. Previous research focused on aggregate penetration for mobile and fixed broadband services. Our research analyzes the economic relationship between mobile and fixed broadband services at the household level, as a basis for how senior managers should rethink their strategy approach. Using data on broadband services subscriptions, we examine how changes that occur for mobile broadband services bandwidth (MBB) affect changes in fixed broadband bandwidth (FBB) services subscriptions, inclusive of new subscriptions - and vice versa. We explore the different …