OS and Networks Commons^™

Virtual Wired Transmission Scheme - A Novel Technique For Efficient Mobile Adhoc Networks, Manikya Vinay Rali

Electrical & Computer Engineering Theses & Dissertations

This thesis proposes a method called virtual wired transmission scheme for ad hoc networks. The scheme is an efficient method to improve network performance parameters such as energy efficiency, capacity, interference, network throughput, etc. Performance parameters improvement can be done at different layers of the network architecture for mobile ad hoc networks. However most of the research efforts are concentrated on Physical, MAC and Network layers. In this thesis, a MAC protocol with a major MAC layer modification is proposed in combination with the usage of directional antennas, developing a novel method called virtual wired transmission scheme. In virtual wired …

“Best K”: Critical Clustering Structures In Categorical Datasets, Keke Chen, Ling Liu

Kno.e.sis Publications

The demand on cluster analysis for categorical data continues to grow over the last decade. A well-known problem in categorical clustering is to determine the best K number of clusters. Although several categorical clustering algorithms have been developed, surprisingly, none has satisfactorily addressed the problem of best K for categorical clustering. Since categorical data does not have an inherent distance function as the similarity measure, traditional cluster validation techniques based on geometric shapes and density distributions are not appropriate for categorical data. In this paper, we study the entropy property between the clustering results of categorical data with different K …

Tableau Algorithm For Concept Satisfiability In Description Logic Alch, Satya S. Sahoo, Krishnaprasad Thirunarayan

Kno.e.sis Publications

The provenir ontology is an upper-level ontology to facilitate interoperability of provenance information in scientific applications. The description logic (DL) expressivity of provenir ontology is ALCH, that is, it models role hierarchies (H) (without transitive roles and inverse roles). Even though the complexity results for concept satisfiability for numerous variants of DL such as ALC with transitively closed roles (ALC_R+ also called S), inverse roles SI, and role hierarchy SHI have been well-established, similar results for ALCH has been surprisingly missing from the literature. Here, we show that the complexity of the concept satisfiability problem for the ALCH variant …

Evolution Versus Revolution As A Strategy For Thin Client Acceptance: Case Study, Paul Doyle, Mark Deegan, Ciaran O'Driscoll

Conference papers

Thin Clients have evolved from simple text based CRT dumb terminal devices in the 1960s, into a sophisticated architecture encompassing hardware, software, networks and protocols. However despite this recent evolution the Thin Client model has yet to re-emerge as a relevant design in an IT industry where Fat Clients (desktops and laptops) thrive. This paper describes two case studies performed within the Technological University Dublin School of Computing, focused on the issue of student acceptance of this technology. The first case study provides a dedicated single service Thin Client implementation, while the second case study adopts a process of coexistence …

Ontology Supported Knowledge Discovery In The Field Of Human Performance And Cognition, Christopher Thomas, Pablo N. Mendes, Delroy H. Cameron, Amit P. Sheth, Krishnaprasad Thirunarayan, Cartic Ramakrishnan

Kno.e.sis Publications

No abstract provided.

Analysis And Monetization Of Social Data, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Extending Sparql To Support Spatially And Temporally Related Information, Prateek Jain, Amit P. Sheth, Peter Z. Yeh, Kunal Verma

Kno.e.sis Publications

No abstract provided.

Trykipedia: Collaborative Bio-Ontology Development Using Wiki Environment, Pramod Anantharam, Satya S. Sahoo, Brent Weatherly, Flora Logan, Raghava Mutharaju, Amit P. Sheth, Rick L. Tarleton

Kno.e.sis Publications

Biomedical ontology development is an intensely collaborative process between biology experts and computer scientists. With the proliferation of ontology based approach to solve informatics problems in biological domain, there is a need for collaborative environment that is intuitive and widely accepted for modeling the ontology.

Operational Verification Of A Relativistic Program, Robert T. Bauer

Computer Science Faculty Publications and Presentations

Engineering eorts to achieve scalable multiprocessor perfor- mance for concurrent reader-writer programs have resulted in a family of algorithms that are non-blocking and that tolerate interprocessor in- terference. Because these algorithms accept a unique frame of reference for each processor's accesses to memory, they typify a concurrent pro- gramming technique for shared memory multicore architectures called relativistic programmming.

Rigorous verification of these algorithms is not possible with existing semantic based approaches because the semantics under approximates multiprocessor behavior and the algorithms rely on abstruse interactions with the operating system that aren't reconciled with language seman- tics.

The Read-Copy Update (RCU) …

Residual-Based Estimation Of Peer And Link Lifetimes In P2p Networks, Xiaoming Wang, Zhongmei Yao, Dmitri Loguinov

Computer Science Faculty Publications

Existing methods of measuring lifetimes in P2P systems usually rely on the so-called Create-BasedMethod (CBM), which divides a given observation window into two halves and samples users ldquocreatedrdquo in the first half every Delta time units until they die or the observation period ends. Despite its frequent use, this approach has no rigorous accuracy or overhead analysis in the literature. To shed more light on its performance, we first derive a model for CBM and show that small window size or large Delta may lead to highly inaccurate lifetime distributions. We then show that create-based sampling exhibits an inherent …

An Ontological Representation Of Time Series Observations On The Semantic Sensor Web, Cory Andrew Henson, Holger Neuhaus, Amit P. Sheth, Krishnaprasad Thirunarayan, Rajkumar Buyya

Kno.e.sis Publications

Time series observations are a common method of collecting sensor data. The Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) provides a standard representation for time series observations within the Observations and Measurements language, and therefore is in heavy use on the Sensor Web. By providing a common model, Observations and Measurements (O&M) facilitates syntax-level integration, but lacks the ability to facilitate semantic-level integration. This inability can cause problems with interoperability between disparate sensor networks that may have subtle variations in their sensing methods. An ontological representation of time series observations could provide a more expressive model and resolve problems …

Interference-Aware Routing Protocol In Multi-Radio Wireless Mesh Networks, Byoungheon Shin, Yangwoo Ko, Jisun An, Dongman Lee

Research Collection School Of Computing and Information Systems

Utilization of multiple radio interfaces increases throughput of wireless networks. Existing work proposes a multi-radio routing protocol exploiting link quality and channel diversity of a path. While an established path is deteriorated by interferences incurred by any changes in a network, and existing work does not detect the deterioration. In this paper, we propose an interference-aware multi-radio routing protocol detecting and resolving dynamic path deterioration in wireless mesh networks.

Store And Forward Routing For Sparse Pico-Satellite Sensor Networks With Data-Mules, Trevor Joseph Koritza

Master's Theses

Satellites are playing an increasingly important role in collecting scientific information, providing communication services, and revolutionizing navigation. Until recently satellites were large and very expensive, creating a high barrier to entry that only large corporations and government agencies could overcome. In the past few years the CubeSat project at California Polytechnic University in San Luis Obispo (Cal Poly) has worked to refine the design and launching of small, lightweight, and less expensive satellites called pico-satellites, opening space up to a wider audience. Now that Cal Poly has the launch logistics and hardware under control, a new problem has arisen. These …

Situation Awareness Via Abductive Reasoning For Semantic Sensor Data: A Preliminary Report, Krishnaprasad Thirunarayan, Cory Andrew Henson, Amit P. Sheth

Kno.e.sis Publications

Semantic sensor Web enhances raw sensor data with spatial, temporal, and thematic annotations to enable high-level reasoning. In this paper, we explore how abductive reasoning framework can benefit formalization and interpretation of sensor data to garner situation awareness. Specifically, we show how abductive logic programming techniques, in conjunction with symbolic knowledge rules, can be used to detect inconsistent sensor data and to generate human accessible description of the state of the world from consistent subset of the sensor data. We also show how trust/belief information can be incorporated into the interpreter to enhance reliability. For concreteness, we formalize weather domain …

Semsos: Semantic Sensor Observation Service, Cory Andrew Henson, Josh Pschorr, Amit P. Sheth, Krishnaprasad Thirunarayan

Kno.e.sis Publications

Sensor observation service (SOS) is a Web service specification defined by the Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) group in order to standardize the way sensors and sensor data are discovered and accessed on the Web. This standard goes a long way in providing interoperability between repositories of heterogeneous sensor data and applications that use this data. Many of these applications, however, are ill equipped at handling raw sensor data as provided by SOS and require actionable knowledge of the environment in order to be practically useful. There are two approaches to deal with this obstacle, make the …

A Hidden Markov Model Based Approach To Detect Rogue Access Points, Gayathri Shivaraj

Electrical & Computer Engineering Theses & Dissertations

One of the most challenging security concerns for network administrators is the presence of Rogue access points. The challenge is to detect and disable a Rogue access point before it can cause hazardous damage to the network. This thesis proposes a statistically based approach to detect Rogue access points using a Hidden Markov Model, which is applied to passively measure packet-header data collected at a gateway router or any monitoring point. This approach utilizes variations in packet inter-arrival time to differentiate between authorized access points and Rouge access points. This approach used the inter-arrival time of a packet as a …

Pipelined Apache Http Server, Kevin Le

Master's Theses

Web servers often become overloaded with irregular surges in web traffic. Several techniques have been explored to cope with these overloads such as distributing load throughout different servers. This thesis presents Pipelined Apache HTTP Server, a modified version of the Apache Software Foundation’s HTTP Server that utilizes a pipelined execution of Apache’s request cycle. We discuss Apache’s original architecture, the modifications necessary for implementation of pipelined execution, and analyze its run time. Ultimately, we hoped to increase throughput of Apache but fall short because of unbalanced request phases and pipelining overhead.

Dynamic Network Formation Using Ant Colony Optimization, Steven C. Oimoen

Theses and Dissertations

Military and industry are moving toward every device being network enabled and connected for reliable availability of communication and information. To make this type of system a reality, the devices must be capable of forming a network topology on their own in a dynamic environment to ensure that the correct information reaches a desired location and on-time. This research presents three contributions for solving highly dynamic (i.e. drastic change within the network) Multi-commodity Capacitated Network Design Problems (MCNDPs) resulting in a distributed multi-agent network design algorithm. The first contribution incorporates an Ant Colony Optimization (ACO) algorithm Ant Colony System (ACS) …

Using Predictive Rendering As A Vision-Aided Technique For Autonomous Aerial Refueling, Adam D. Weaver

Theses and Dissertations

This research effort seeks to characterize a vision-aided approach for an Unmanned Aerial System (UAS) to autonomously determine relative position to another aircraft in a formation, specifically to address the autonomous aerial refueling problem. A system consisting of a monocular digital camera coupled with inertial sensors onboard the UAS is analyzed for feasibility of using this vision-aided approach. A three-dimensional rendering of the tanker aircraft is used to generate predicted images of the tanker as seen by the receiver aircraft. A rigorous error model is developed to model the relative dynamics between an INS-equipped receiver and the tanker aircraft. A …

A Social Relation Aware Routing Protocol For Mobile Ad Hoc Networks, Jisun An, Yangwoo Ko, Dongman Lee

Research Collection School Of Computing and Information Systems

In this paper, we propose a social relation aware routing protocol for mobile ad hoc networks, which is designed for content sharing mobile social applications. Since a content can be shared by a group of users who have similar interests, the similarity of users' interests is a good metric to predict who will consume which contents. Shared interests can be exploited in routing and replication of content request and reply to achieve enhanced efficacy in content sharing. Since routing determines which content will be forwarded by whom, a route selected based on similarity of interest increases the utilization of contents …

Semantic Integration Of Citizen Sensor Data And Multilevel Sensing: A Comprehensive Path Towards Event Monitoring And Situational Awareness, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Computing For Human Experience: Sensors, Perception, Semantics, Web N.0, And Beyond, Amit P. Sheth

Kno.e.sis Publications

Traditionally there has been a strong separation between computing and human activities in the real world. The approach has largely been that of mapping the complexity and richness of the real world to constrained computer models and languages for more efficient computation, and then transferring the results for use in the real world. I think the time is ripe to reverse the situation, for computing and communication to transparently enrich and enhance human experience. Today, devices enable something more than a 'human instructs machine' paradigm. We are seeing computing and communication engage transparently in human activities by enriching them in …

Node Isolation Model And Age-Based Neighbor Selection In Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov

Computer Science Faculty Publications

Previous analytical studies of unstructured P2P resilience have assumed exponential user lifetimes and only considered age-independent neighbor replacement. In this paper, we overcome these limitations by introducing a general node-isolation model for heavy-tailed user lifetimes and arbitrary neighbor-selection algorithms. Using this model, we analyze two age-biased neighbor-selection strategies and show that they significantly improve the residual lifetimes of chosen users, which dramatically reduces the probability of user isolation and graph partitioning compared with uniform selection of neighbors. In fact, the second strategy based on random walks on age-proportional graphs demonstrates that, for lifetimes with infinite variance, the system monotonically increases …

Why Gujarat Needs Much Better Higher Education & Research To Succeed In Knowledge Economy & What We Can Do About It?, Amit P. Sheth, Kamlesh Lulla, Sanjay Chaudhary

Kno.e.sis Publications

This white paper distills the deliberations on the role of higher education and research as a key enabler of a Knowledge based Society. In particular it discusses (a) the importance of higher quality PhDs for building a knowledge society, (b) the initiatives and progress in competing economies in higher education and research, (c) where Gujarat stands in comparison, and (d) some recommendations on what Gujarat can do to enable timely progress towards building a knowledge based society and economy. These deliberations were conducted in conjunction with the International Conference on 'Reconnecting Gujarati Diaspora with its Homeland: Contribution to its Development …

Ontologies And Rules, Pascal Hitzler, Bijan Parsia

Computer Science and Engineering Faculty Publications

Ontologies and rules are two established paradigms in knowledge modelling, and play an important role for the Semantic Web. In this chapter, we present an introduction to common approaches for combining OWL ontologies and rules. In particular, we cover the Semantic Web Rules Language SWRL and Description Logic Programs DLP, and give pointers to the literature.

User-Generated Content On Social Media Challenges, Opportunities, Meenakshi Nagarajan

Kno.e.sis Publications

Understanding and exploiting user generated (textual) content (UGC) on social media is at the forefront of information management challenges today. The variety of UGC in detailed blog commentaries, collaborative wiki-content, online conversations, short messages in micro-blogs etc., are powering several personalization, monetization, crowd/business intelligence applications, and also providing an electronic microscope on social phenomena at an extraordinary scale. Certain characteristics of UGC however, necessitate key computational linguistic interventions before systems can tap into this data. A large portion of language found on social media is in the Informal English domain a blend of abbreviations, slang and context dependent terms delivered …

Citizen Sensing, Social Signals, And Enriching Human Experience, Amit P. Sheth

Kno.e.sis Publications

In this article, I introduce the exciting paradigm of citizen sensing enabled by mobile sensors and human computing - that is, humans as citizens on the ubiquitous Web, acting as sensors and sharing their observations and views using mobile devices and Web 2.0 services.

Semantics-Empowered Social Computing, Amit P. Sheth, Meenakshi Nagarajan

Kno.e.sis Publications

In this article, we discuss some of the challenges in marking-up or annotating UGC, a first step toward the realization of the social semantic Web. Using examples from real- world UGC, we show how domain knowledge can effectively complement statistical natural language processing techniques for metadata creation.

Prom: A Semantic Web Framework For Provenance Management In Science, Satya S. Sahoo, Roger Barga, Amit P. Sheth, Krishnaprasad Thirunarayan, Pascal Hitzler

Kno.e.sis Publications

The eScience paradigm is enabling researchers to collaborate over the Web in virtual laboratories and conduct experiments on an industrial scale. But, the inherent variability in the quality and trust associated with eScience resources necessitates the use of provenance information describing the origin of an entity. Existing systems often model provenance using ambiguous terminology, have poor domain semantics and include modeling inconsistencies that hinders interoperability. Further, mere collection of provenance information is of little value without a well-defined and scalable query mechanism.

In this paper, we present 'PrOM', a framework that addresses both the modeling and querying issues in eScience …

The Impact Of Communication Medium On Team Performance Patterns, Pilar Pazos, Mario G. Beruvides

Engineering Management & Systems Engineering Faculty Publications

The increased impact of globalization and rapidly changing technologies are some of the biggest challenges facing 21st century organizations. Remote teams supported through computer-based systems have been identified as a key lever to help organizations adapt to this turbulent environment. This study sheds some light on how teams perform and adapt by evaluating performance and synergy over time for teams in two different settings: computer supported and face-to-face. Participants in the study were randomly assigned either to a computer-supported or a face-to face group. Each group met over three sessions to perform a series of tasks that were evaluated using …