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Full-Text Articles in Computer Sciences

From Footprint To Evidence: An Exploratory Study Of Mining Social Data For Credit Scoring, Guangming Guo, Feida Zhu, Enhong Chen, Qi Liu, Le Wu, Chu Guan Dec 2016

From Footprint To Evidence: An Exploratory Study Of Mining Social Data For Credit Scoring, Guangming Guo, Feida Zhu, Enhong Chen, Qi Liu, Le Wu, Chu Guan

Research Collection School Of Computing and Information Systems

With the booming popularity of online social networks like Twitter and Weibo, online user footprints are accumulating rapidly on the social web. Simultaneously, the question of how to leverage the large-scale user-generated social media data for personal credit scoring comes into the sight of both researchers and practitioners. It has also become a topic of great importance and growing interest in the P2P lending industry. However, compared with traditional financial data, heterogeneous social data presents both opportunities and challenges for personal credit scoring. In this article, we seek a deep understanding of how to learn users’ credit labels from social …

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Cast2face: Assigning Character Names Onto Faces In Movie With Actor-Character Correspondence, Guangyu Gao, Mengdi Xu, Jialie Shen, Huangdong Ma, Shuicheng Yan Dec 2016

Cast2face: Assigning Character Names Onto Faces In Movie With Actor-Character Correspondence, Guangyu Gao, Mengdi Xu, Jialie Shen, Huangdong Ma, Shuicheng Yan

Research Collection School Of Computing and Information Systems

Automatically identifying characters in movies has attracted researchers' interest and led to several significant and interesting applications. However, due to the vast variation in character appearance as well as the weakness and ambiguity of available annotation, it is still a challenging problem. In this paper, we investigate this problem with the supervision of actor-character name correspondence provided by the movie cast. Our proposed framework, namely, Cast2Face, is featured by: 1) we restrict the assigned names within the set of character names in the cast; 2) for each character, by using the corresponding actor and movie name as keywords, we retrieve …

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Careermapper: An Automated Resume Evaluation Tool, Vivian Lai, Kyong Jin Shim, Richard J. Oentaryo, Philips K. Prasetyo, Casey Vu, Ee-Peng Lim, David Lo Dec 2016

Careermapper: An Automated Resume Evaluation Tool, Vivian Lai, Kyong Jin Shim, Richard J. Oentaryo, Philips K. Prasetyo, Casey Vu, Ee-Peng Lim, David Lo

Research Collection School Of Computing and Information Systems

The advent of the Web brought about major changes in the way people search for jobs and companies look for suitable candidates. As more employers and recruitment firms turn to the Web for job candidate search, an increasing number of people turn to the Web for uploading and creating their online resumes. Resumes are often the first source of information about candidates and also the first item of evaluation in candidate selection. Thus, it is imperative that resumes are complete, free of errors and well-organized. We present an automated resume evaluation tool called 'CareerMapper'. Our tool is designed to conduct …

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Ciphertext-Policy Attribute-Based Encryption With Partially Hidden Access Structure And Its Application To Privacy-Preserving Electronic Medical Record System In Cloud Environment, Lixian Liu, Junzuo Lai, Robert H. Deng, Yingjiu Li Dec 2016

Ciphertext-Policy Attribute-Based Encryption With Partially Hidden Access Structure And Its Application To Privacy-Preserving Electronic Medical Record System In Cloud Environment, Lixian Liu, Junzuo Lai, Robert H. Deng, Yingjiu Li

Research Collection School Of Computing and Information Systems

With the development of cloud computing, more and more sensitive data are uploaded to cloud by companies or individuals, which brings forth new challenges for outsourced data security and privacy. Ciphertext-policy attribute-based encryption (CP-ABE) provides fine-grained access control of encrypted data in the cloud; in a CP-ABE scheme, an access structure, also referred to as ciphertext-policy, is sent along with a ciphertext explicitly, and anyone who obtains a ciphertext can know the access structure associated with the ciphertext. In certain applications, access structures contain very sensitive information and must be protected from everyone except the users whose private key attributes …

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Collective Personalized Change Classification With Multiobjective Search, Xin Xia, David Lo, Xinyu Wang, Xiaohu Yang Dec 2016

Collective Personalized Change Classification With Multiobjective Search, Xin Xia, David Lo, Xinyu Wang, Xiaohu Yang

Research Collection School Of Computing and Information Systems

Many change classification techniques have been proposed to identify defect-prone changes. These techniques consider all developers' historical change data to build a global prediction model. In practice, since developers have their own coding preferences and behavioral patterns, which causes different defect patterns, a separate change classification model for each developer can help to improve performance. Jiang, Tan, and Kim refer to this problem as personalized change classification, and they propose PCC+ to solve this problem. A software project has a number of developers; for a developer, building a prediction model not only based on his/her change data, but also on …

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Demystifying And Puncturing The Inflated Delay In Smartphone-Based Wifi Network Measurement, Weichao Li, Daoyuan Wu, Rocky K. C. Chang, Ricky K. P. Mok Dec 2016

Demystifying And Puncturing The Inflated Delay In Smartphone-Based Wifi Network Measurement, Weichao Li, Daoyuan Wu, Rocky K. C. Chang, Ricky K. P. Mok

Research Collection School Of Computing and Information Systems

Using network measurement apps has become a very effective approach to crowdsourcing WiFi network performance data. However, these apps usually measure the user-level performancemetrics instead of the network-level performance which is important for diagnosing performance problems. In this paper we report for the first time that a major source of measurement noises comes from the periodical SDIO (Secure Digital Input Output) bus sleep inside the phone. The additional latency introduced by SDIO and Power Saving Mode can inflate and unstablize network delay measurement significantly. We carefully design and implement a scheme to wake up the phone for delay measurement by …

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Domain Identification For Intention Posts On Online Social Media, Thai Le Luong, Quoc Tuan Truong, Hai-Trieu Dang, Xuan Hieu Phan Dec 2016

Domain Identification For Intention Posts On Online Social Media, Thai Le Luong, Quoc Tuan Truong, Hai-Trieu Dang, Xuan Hieu Phan

Research Collection School Of Computing and Information Systems

Today, more and more Internet users are willing to share their feeling, activities, and even their intention about what they plan to do on online social media. We can easily see posts like "I plan to buy an apartment this year", or "We are looking for a tour for 3 people to Nha Trang" on online forums or social networks. Recognizing those user intents on online social media is really useful for targeted advertising. However fully understanding user intents is a complicated and challenging process which includes three major stages: user intent filtering, intent domain identification, and intent parsing and …

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Server-Aided Public Key Encryption With Keyword Search, Rongman Chen, Yi Mu, Guomin Yang, Fuchun Guo, Xinyi Huang, Xiaofen Wang, Yongjun Wang Dec 2016

Server-Aided Public Key Encryption With Keyword Search, Rongman Chen, Yi Mu, Guomin Yang, Fuchun Guo, Xinyi Huang, Xiaofen Wang, Yongjun Wang

Research Collection School Of Computing and Information Systems

Public key encryption with keyword search (PEKS) is a well-known cryptographic primitive for secure searchable data encryption in cloud storage. Unfortunately, it is inherently subject to the (inside) offline keyword guessing attack (KGA), which is against the data privacy of users. Existing countermeasures for dealing with this security issue mainly suffer from low efficiency and are impractical for real applications. In this paper, we provide a practical and applicable treatment on this security vulnerability by formalizing a new PEKS system named server-aided public key encryption with keyword search (SA-PEKS). In SA-PEKS, to generate the keyword ciphertext/trapdoor, the user needs to …

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Cryptographic Reverse Firewall Via Malleable Smooth Projective Hash Functions, Rongmao Chen, Guomin Yang, Guomin Yang, Willy Susilo, Fuchun Guo, Mingwu Zhang Dec 2016

Cryptographic Reverse Firewall Via Malleable Smooth Projective Hash Functions, Rongmao Chen, Guomin Yang, Guomin Yang, Willy Susilo, Fuchun Guo, Mingwu Zhang

Research Collection School Of Computing and Information Systems

Motivated by the revelations of Edward Snowden, postSnowden cryptography has become a prominent research direction in recent years. In Eurocrypt 2015, Mironov and Stephens-Davidowitz proposed a novel concept named cryptographic reverse firewall (CRF) which can resist exfiltration of secret information from an arbitrarily compromised machine. In this work, we continue this line of research and present generic CRF constructions for several widely used cryptographic protocols based on a new notion named malleable smooth projective hash function. Our contributions can be summarized as follows. – We introduce the notion of malleable smooth projective hash function, which is an extension of the …

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Iterated Random Oracle: A Universal Approach For Finding Loss In Security Reduction, Fuchun Guo, Willy Susilo, Yi Mu, Rongmao Chen, Jianchang Lai, Guomin Yang Dec 2016

Iterated Random Oracle: A Universal Approach For Finding Loss In Security Reduction, Fuchun Guo, Willy Susilo, Yi Mu, Rongmao Chen, Jianchang Lai, Guomin Yang

Research Collection School Of Computing and Information Systems

The indistinguishability security of a public-key cryptosystem can be reduced to a computational hard assumption in the random oracle model, where the solution to a computational hard problem is hidden in one of the adversary’s queries to the random oracle. Usually, there is a finding loss in finding the correct solution from the query set, especially when the decisional variant of the computational problem is also hard. The problem of finding loss must be addressed towards tight(er) reductions under this type. In EUROCRYPT 2008, Cash, Kiltz and Shoup proposed a novel approach using a trapdoor test that can solve the …

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Semi-Automated Tool For Providing Effective Feedback On Programming Assignments, Min Yan Beh, Swapna Gottipati, David Lo, Venky Shankararaman Dec 2016

Semi-Automated Tool For Providing Effective Feedback On Programming Assignments, Min Yan Beh, Swapna Gottipati, David Lo, Venky Shankararaman

Research Collection School Of Computing and Information Systems

Human grading of introductory programming assignments is tedious and error-prone, hence researchers have attempted to develop tools that support automatic assessment of programming code. However, most such efforts often focus only on scoring solutions, rather than assessing whether students correctly understand the problems. To aid the students improve programming skills, effective feedback on programming assignments plays an important role. Individual feedback generation is tedious and painstaking process. We present a tool that not only automatically generates the static and dynamic program analysis outcomes, but also clusters similar code submissions to provide scalable and effective feedback to the students. We studied …

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Attacking Android Smartphone Systems Without Permissions, Mon Kywe Su, Yingjiu Li, Kunal Petal, Michael Grace Dec 2016

Attacking Android Smartphone Systems Without Permissions, Mon Kywe Su, Yingjiu Li, Kunal Petal, Michael Grace

Research Collection School Of Computing and Information Systems

Android requires third-party applications to request for permissions when they access critical mobile resources, such as users' personal information and system operations. In this paper, we present the attacks that can be launched without permissions. We first perform call graph analysis, component analysis and data-flow analysis on various parts of Android framework to retrieve unprotected APIs. Unprotected APIs provide a way of accessing resources without any permissions. We then exploit selected unprotected APIs and launch a number of attacks on Android phones. We discover that without requesting for any permissions, an attacker can access to device ID, phone service state, …

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Orienteering Problem: A Survey Of Recent Variants, Solution Approaches And Applications, Aldy Gunawan, Hoong Chuin Lau, Pieter Vansteenwegen Dec 2016

Orienteering Problem: A Survey Of Recent Variants, Solution Approaches And Applications, Aldy Gunawan, Hoong Chuin Lau, Pieter Vansteenwegen

Research Collection School Of Computing and Information Systems

Duplicate record, see https://ink.library.smu.edu.sg/sis_research/3271. The Orienteering Problem (OP) has received a lot of attention in the past few decades. The OP is a routing problem in which the goal is to determine a subset of nodes to visit, and in which order, so that the total collected score is maximized and a given time budget is not exceeded. A number of typical variants has been studied, such as the Team OP, the (Team) OP with Time Windows and the Time Dependent OP. Recently, a number of new variants of the OP was introduced, such as the Stochastic OP, the …

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Lexicon Knowledge Extraction With Sentiment Polarity Computation, Zhaoxia Wang, Vincent Joo Chuan Tong, Pingcheng Ruan, Fang Li Dec 2016

Lexicon Knowledge Extraction With Sentiment Polarity Computation, Zhaoxia Wang, Vincent Joo Chuan Tong, Pingcheng Ruan, Fang Li

Research Collection School Of Computing and Information Systems

Sentiment analysis is one of the most popular natural language processing techniques. It aims to identify the sentiment polarity (positive, negative, neutral or mixed) within a given text. The proper lexicon knowledge is very important for the lexicon-based sentiment analysis methods since they hinge on using the polarity of the lexical item to determine a text's sentiment polarity. However, it is quite common that some lexical items appear positive in the text of one domain but appear negative in another. In this paper, we propose an innovative knowledge building algorithm to extract sentiment lexicon knowledge through computing their polarity value …

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Lossy Key Encapsulation Mechanism And Its Applications, Yamin Liu, Xianhui Lu, Bao Li, Haiyang Xue Dec 2016

Lossy Key Encapsulation Mechanism And Its Applications, Yamin Liu, Xianhui Lu, Bao Li, Haiyang Xue

Research Collection School Of Computing and Information Systems

We introduce a new notion, lossy key encapsulation mechanism (lossy KEM), which enhances the notion of key encapsulation mechanism with lossiness, and can be more efficient than lossy trapdoor functions. We show that lossy KEM can be constructed from lossy trapdoor functions, lossy trapdoor relations, and entropic projective hashing. Using lossy KEM as a building block, several previous constructions of lossy encryption and deterministic public key encryption can be generalized and improved in efficiency.

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Impact Of Isp, Bpr, And Customization On Erp Performance In Manufacturing Smes Of Korea, Soon-Goo Hong, Keng Siau, Jong-Weon Kim Dec 2016

Impact Of Isp, Bpr, And Customization On Erp Performance In Manufacturing Smes Of Korea, Soon-Goo Hong, Keng Siau, Jong-Weon Kim

Research Collection School Of Computing and Information Systems

Purpose: This paper aims to assess how enterprise resource planning (ERP) performance of Korean small and medium enterprises in manufacturing differs according to different levels of business process reengineering (BPR), information strategic planning (ISP) and ERP customization. Design/methodology/approach: A questionnaire survey was carried out in this research. Responses from 96 small and medium manufacturing companies that have adopted ERP systems were analyzed. Findings: The results of this study suggest that ISP and BPR implementation are positively correlated to ERP performance. Originality/value: While consulting and customization costs have positive impacts on ERP performance, the level of customization does not influence performance. …

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Coherence, Richness And Cognitive Absorption In Website Design, L. Visinescu, Fiona Fui-Hoon Nah Dec 2016

Coherence, Richness And Cognitive Absorption In Website Design, L. Visinescu, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

Kaplan’s theory on environmental preferences can offer a holistic perspective on cognitive absorption in ecommerce website design. Drawing on Kaplan’s theory, this paper proposes that coherence and richness of a website can enhance cognitive absorption of users. The findings from our study not only support the hypotheses, but also suggest that coherence and richness can reach an optimal proportion in website design, after which they are inversely correlated.

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Zero++: Harnessing The Power Of Zero Appearances To Detect Anomalies In Large-Scale Data Sets, Guansong Pang, Kai Ming Ting, David Albrecht, Huidong Jin Dec 2016

Zero++: Harnessing The Power Of Zero Appearances To Detect Anomalies In Large-Scale Data Sets, Guansong Pang, Kai Ming Ting, David Albrecht, Huidong Jin

Research Collection School Of Computing and Information Systems

This paper introduces a new unsupervised anomaly detector called ZERO++ which employs the number of zero appearances in subspaces to detect anomalies in categorical data. It is unique in that it works in regions of subspaces that are not occupied by data; whereas existing methods work in regions occupied by data. ZERO++ examines only a small number of low dimensional subspaces to successfully identify anomalies. Unlike existing frequencybased algorithms, ZERO++ does not involve subspace pattern searching. We show that ZERO++ is better than or comparable with the state-of-the-art anomaly detection methods over a wide range of real-world categorical and numeric …

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Unsupervised Feature Selection For Outlier Detection By Modelling Hierarchical Value-Feature Couplings, Guansong Pang, Longbing Cao, Ling Chen, Huan Liu Dec 2016

Unsupervised Feature Selection For Outlier Detection By Modelling Hierarchical Value-Feature Couplings, Guansong Pang, Longbing Cao, Ling Chen, Huan Liu

Research Collection School Of Computing and Information Systems

Proper feature selection for unsupervised outlier detection can improve detection performance but is very challenging due to complex feature interactions, the mixture of relevant features with noisy/redundant features in imbalanced data, and the unavailability of class labels. Little work has been done on this challenge. This paper proposes a novel Coupled Unsupervised Feature Selection framework (CUFS for short) to filter out noisy or redundant features for subsequent outlier detection in categorical data. CUFS quantifies the outlierness (or relevance) of features by learning and integrating both the feature value couplings and feature couplings. Such value-to-feature couplings capture intrinsic data characteristics and …

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Towards Learning And Verifying Invariants Of Cyber-Physical Systems By Code Mutation, Yuqi Chen, Christopher M. Poskitt, Jun Sun Nov 2016

Towards Learning And Verifying Invariants Of Cyber-Physical Systems By Code Mutation, Yuqi Chen, Christopher M. Poskitt, Jun Sun

Research Collection School Of Computing and Information Systems

Cyber-physical systems (CPS), which integrate algorithmic control with physical processes, often consist of physically distributed components communicating over a network. A malfunctioning or compromised component in such a CPS can lead to costly consequences, especially in the context of public infrastructure. In this short paper, we argue for the importance of constructing invariants (or models) of the physical behaviour exhibited by CPS, motivated by their applications to the control, monitoring, and attestation of components. To achieve this despite the inherent complexity of CPS, we propose a new technique for learning invariants that combines machine learning with ideas from mutation testing. …

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Towards Learning And Verifying Invariants Of Cyber-Physical Systems By Code Mutation, Yuqi Chen, Christopher M. Poskitt, Jun Sun Nov 2016

Towards Learning And Verifying Invariants Of Cyber-Physical Systems By Code Mutation, Yuqi Chen, Christopher M. Poskitt, Jun Sun

Research Collection School Of Computing and Information Systems

Cyber-physical systems (CPS), which integrate algorithmic control with physical processes, often consist of physically distributed components communicating over a network. A malfunctioning or compromised component in such a CPS can lead to costly consequences, especially in the context of public infrastructure. In this short paper, we argue for the importance of constructing invariants (or models) of the physical behaviour exhibited by CPS, motivated by their applications to the control, monitoring, and attestation of components. To achieve this despite the inherent complexity of CPS, we propose a new technique for learning invariants that combines machine learning with ideas from mutation testing. …

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Towards Concolic Testing For Hybrid Systems, Pingfan Kong, Yi Li, Xiaohong Chen, Jun Sun, Meng Sun, Jingyi Wang Nov 2016

Towards Concolic Testing For Hybrid Systems, Pingfan Kong, Yi Li, Xiaohong Chen, Jun Sun, Meng Sun, Jingyi Wang

Research Collection School Of Computing and Information Systems

Hybrid systems exhibit both continuous and discrete behavior. Analyzing hybrid systems is known to be hard. Inspired by the idea of concolic testing (of programs), we investigate whether we can combine random sampling and symbolic execution in order to effectively verify hybrid systems. We identify a sufficient condition under which such a combination is more effective than random sampling. Furthermore, we analyze different strategies of combining random sampling and symbolic execution and propose an algorithm which allows us to dynamically switch between them so as to reduce the overall cost. Our method has been implemented as a web-based checker named …

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Automated Verification Of Timed Security Protocols With Clock Drift, Li Li, Jun Sun Nov 2016

Automated Verification Of Timed Security Protocols With Clock Drift, Li Li, Jun Sun

Research Collection School Of Computing and Information Systems

Time is frequently used in security protocols to provide better security. For instance, critical credentials often have limited lifetime which improves the security against brute-force attacks. However, it is challenging to correctly use time in protocol design, due to the existence of clock drift in practice. In this work, we develop a systematic method to formally specify as well as automatically verify timed security protocols with clock drift. We first extend the previously proposed timed applied ππ -calculus as a formal specification language for timed protocols with clock drift. Then, we define its formal semantics based on timed logic rules, …

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Rapid Deployment Indoor Localization Without Prior Human Participation, Han Xu, Zimu Zhou, Longfei Shangguan Nov 2016

Rapid Deployment Indoor Localization Without Prior Human Participation, Han Xu, Zimu Zhou, Longfei Shangguan

Research Collection School Of Computing and Information Systems

In this work, we propose RAD, a RApid Deployment localization framework without human sampling. The basic idea of RAD is to automatically generate a fingerprint database through space partition, of which each cell is fingerprinted by its maximum influence APs. Based on this robust location indicator, fine-grained localization can be achieved by a discretized particle filter utilizing sensor data fusion. We devise techniques for CIVD-based field division, graph-based particle filter, EM-based individual character learning, and build a prototype that runs on commodity devices. Extensive experiments show that RAD provides a comparable performance to the state-of-the-art RSSbased methods while relieving it …

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Improving Quality Of Use Case Documents Through Learning And User Interaction, Shuang Liu, Jun Sun, Hao Xiao, Bimlesh Wadhwa, Jin Song Dong, Xinyu Wang Nov 2016

Improving Quality Of Use Case Documents Through Learning And User Interaction, Shuang Liu, Jun Sun, Hao Xiao, Bimlesh Wadhwa, Jin Song Dong, Xinyu Wang

Research Collection School Of Computing and Information Systems

Use cases are widely used to capture user requirements based on interactions between different roles in the system. They are mostly documented in natural language and sometimes aided with graphical illustrations in the form of use case diagrams. Use cases serve as an important means to communicate among stakeholders, requirement engineers and system engineers as they are easy to understand and are produced early in the software development process. Having high quality use cases are beneficial in many ways, e.g., in avoiding inconsistency/incompleteness in requirements, in guiding system design, in generating test cases. In this work, we propose an approach …

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Towards Using Concurrent Java Api Correctly, Shuang Liu, Guangdong Bai, Jun Sun, Jin Song Dong Nov 2016

Towards Using Concurrent Java Api Correctly, Shuang Liu, Guangdong Bai, Jun Sun, Jin Song Dong

Research Collection School Of Computing and Information Systems

Concurrent Programs are hard to analyze or debug due to the complex program logic and unpredictable execution environment. In practice, ordinary programmers often adopt existing well-designed concurrency related API (e.g., those in java.util.concurrent) so as to avoid dealing with these issues. These API can however often be used incorrectly, which results in hardto-debug concurrent bugs. In this work, we propose an approach for enforcing the correct usage of concurrency-related Java API. Our idea is to annotate concurrency-related Java classes with annotations related to misuse of these API and develop lightweight type checker to detect concurrent API misuse based on the …

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Data Exfiltration Detection And Prevention: Virtually Distributed Pomdps For Practically Safer Networks, Sara Marie Mc Carthy, Arunesh Sinha, Milind Tambe, Pratyusa Manadhata Nov 2016

Data Exfiltration Detection And Prevention: Virtually Distributed Pomdps For Practically Safer Networks, Sara Marie Mc Carthy, Arunesh Sinha, Milind Tambe, Pratyusa Manadhata

Research Collection School Of Computing and Information Systems

We address the challenge of detecting and addressing advanced persistent threats (APTs) in a computer network, focusing in particular on the challenge of detecting data exfiltration over Domain Name System (DNS) queries, where existing detection sensors are imperfect and lead to noisy observations about the network’s security state. Data exfiltration over DNS queries involves unauthorized transfer of sensitive data from an organization to a remote adversary through a DNS data tunnel to a malicious web domain. Given the noisy sensors, previous work has illustrated that standard approaches fail to satisfactorily rise to the challenge of detecting exfiltration attempts. Instead, we …

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Media Reinvented, Geoff Tan Nov 2016

Media Reinvented, Geoff Tan

Asian Management Insights

The brave new world of digital media.

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Asean's Digital Economy, Naveen Menon Nov 2016

Asean's Digital Economy, Naveen Menon

Asian Management Insights

Transforming industries, enriching lives and propelling progress.

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Connecting India, Sam Pitroda Nov 2016

Connecting India, Sam Pitroda

Asian Management Insights

Great inventions will not be born in the absence of the will and intent to embrace change and solve wideranging societal problems.

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