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Computer Engineering Commons

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2010

Selected Works

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Articles 1 - 30 of 66

Full-Text Articles in Computer Engineering

Anonymous Query Processing In Road Networks, Kyriakos Mouratidis, Man Lung Yiu Dec 2010

Anonymous Query Processing In Road Networks, Kyriakos Mouratidis, Man Lung Yiu

Kyriakos MOURATIDIS

The increasing availability of location-aware mobile devices has given rise to a flurry of location-based services (LBSs). Due to the nature of spatial queries, an LBS needs the user position in order to process her requests. On the other hand, revealing exact user locations to a (potentially untrusted) LBS may pinpoint their identities and breach their privacy. To address this issue, spatial anonymity techniques obfuscate user locations, forwarding to the LBS a sufficiently large region instead. Existing methods explicitly target processing in the euclidean space and do not apply when proximity to the users is defined according to network distance …


On-Line Discovery Of Hot Motion Paths, Dimitris Sacharidis, Kostas Patroumpas, Manolis Terrovitis, Verena Kantere, Michalis Potamias, Kyriakos Mouratidis, Timos Sellis Dec 2010

On-Line Discovery Of Hot Motion Paths, Dimitris Sacharidis, Kostas Patroumpas, Manolis Terrovitis, Verena Kantere, Michalis Potamias, Kyriakos Mouratidis, Timos Sellis

Kyriakos MOURATIDIS

We consider an environment of numerous moving objects, equipped with location-sensing devices and capable of communicating with a central coordinator. In this setting, we investigate the problem of maintaining hot motion paths, i.e., routes frequently followed by multiple objects over the recent past. Motion paths approximate portions of objects' movement within a tolerance margin that depends on the uncertainty inherent in positional measurements. Discovery of hot motion paths is important to applications requiring classification/profiling based on monitored movement patterns, such as targeted advertising, resource allocation, etc. To achieve this goal, we delegate part of the path extraction process to objects, …


Continuous Monitoring Of Spatial Queries In Wireless Broadcast Environments, Kyriakos Mouratidis, Spiridon Bakiras, Dimitris Papadias Dec 2010

Continuous Monitoring Of Spatial Queries In Wireless Broadcast Environments, Kyriakos Mouratidis, Spiridon Bakiras, Dimitris Papadias

Kyriakos MOURATIDIS

Wireless data broadcast is a promising technique for information dissemination that leverages the computational capabilities of the mobile devices in order to enhance the scalability of the system. Under this environment, the data are continuously broadcast by the server, interleaved with some indexing information for query processing. Clients may then tune in the broadcast channel and process their queries locally without contacting the server. Previous work on spatial query processing for wireless broadcast systems has only considered snapshot queries over static data. In this paper, we propose an air indexing framework that 1) outperforms the existing (i.e., snapshot) techniques in …


Optimal Matching Between Spatial Datasets Under Capacity Constraints, Hou U Leong, Kyriakos Mouratidis, Man Lung Yiu, Nikos Mamoulis Dec 2010

Optimal Matching Between Spatial Datasets Under Capacity Constraints, Hou U Leong, Kyriakos Mouratidis, Man Lung Yiu, Nikos Mamoulis

Kyriakos MOURATIDIS

Consider a set of customers (e.g., WiFi receivers) and a set of service providers (e.g., wireless access points), where each provider has a capacity and the quality of service offered to its customers is anti-proportional to their distance. The capacity constrained assignment (CCA) is a matching between the two sets such that (i) each customer is assigned to at most one provider, (ii) every provider serves no more customers than its capacity, (iii) the maximum possible number of customers are served, and (iv) the sum of Euclidean distances within the assigned provider-customer pairs is minimized. Although max-flow algorithms are applicable …


Continuous Spatial Assignment Of Moving Users, Leong Hou U, Kyriakos Mouratidis, Nikos Mamoulis Dec 2010

Continuous Spatial Assignment Of Moving Users, Leong Hou U, Kyriakos Mouratidis, Nikos Mamoulis

Kyriakos MOURATIDIS

Consider a set of servers and a set of users, where each server has a coverage region (i.e., an area of service) and a capacity (i.e., a maximum number of users it can serve). Our task is to assign every user to one server subject to the coverage and capacity constraints. To offer the highest quality of service, we wish to minimize the average distance between users and their assigned server. This is an instance of a well-studied problem in operations research, termed optimal assignment. Even though there exist several solutions for the static case (where user locations are fixed), …


Shortest Path Computation On Air Indexes, Georgios Kellaris, Kyriakos Mouratidis Dec 2010

Shortest Path Computation On Air Indexes, Georgios Kellaris, Kyriakos Mouratidis

Kyriakos MOURATIDIS

Shortest path computation is one of the most common queries in location-based services that involve transportation net- works. Motivated by scalability challenges faced in the mo- bile network industry, we propose adopting the wireless broad- cast model for such location-dependent applications. In this model the data are continuously transmitted on the air, while clients listen to the broadcast and process their queries locally. Although spatial problems have been considered in this environment, there exists no study on shortest path queries in road networks. We develop the rst framework to compute shortest paths on the air, and demonstrate the practicality and …


Preference Queries In Large Multi-Cost Transportation Networks, Kyriakos Mouratidis, Yimin Lin, Man Lung Yiu Dec 2010

Preference Queries In Large Multi-Cost Transportation Networks, Kyriakos Mouratidis, Yimin Lin, Man Lung Yiu

Kyriakos MOURATIDIS

Research on spatial network databases has so far considered that there is a single cost value associated with each road segment of the network. In most real-world situations, however, there may exist multiple cost types involved in transportation decision making. For example, the different costs of a road segment could be its Euclidean length, the driving time, the walking time, possible toll fee, etc. The relative significance of these cost types may vary from user to user. In this paper we consider such multi-cost transportation networks (MCN), where each edge (road segment) is associated with multiple cost values. We formulate …


Pre-Eruption Pressure, Temperature And Volatile Content Of Rhyolite Magma From The 1650 Ad Eruption Of Kolumbo Submarine Volcano, Greece, K. Cantner, S. Carey, H. Sigurdsson, G. Vougioukalakis, P. Nomikou, C. Roman, K. Bell, M. Alexandri Dec 2010

Pre-Eruption Pressure, Temperature And Volatile Content Of Rhyolite Magma From The 1650 Ad Eruption Of Kolumbo Submarine Volcano, Greece, K. Cantner, S. Carey, H. Sigurdsson, G. Vougioukalakis, P. Nomikou, C. Roman, K. Bell, M. Alexandri

Christopher N. Roman

Biotite-bearing, crystal-poor rhyolite magma was the predominant magma type discharged during the 1650 AD explosive eruption of Kolumbo submarine volcano, Greece. The eruption produced thick sequences of pumice deposits (~100 m) in the upper crater walls of the volcano, but also led to the formation of extensive pumice rafts that were dispersed throughout the southern Aegean Sea, and subaerial tephra fallout as far east as Turkey. Preliminary estimates of pre-eruption volatile contents have been determined using the volatile-by-difference method on plagioclase-hosted melt inclusions and yield an average value of 6.0 wt.%. This corresponds to a pre-eruption storage pressure of 180 …


Adaptive Checkpointing For Master-Worker Style Parallelism (Extended Abstract), Gene D. Cooperman, Jason Ansel, Xiaoqin Ma Dec 2010

Adaptive Checkpointing For Master-Worker Style Parallelism (Extended Abstract), Gene D. Cooperman, Jason Ansel, Xiaoqin Ma

Gene D. Cooperman

No abstract provided.


Dmtcp: Transparent Checkpointing For Cluster Computations And The Desktop, Jason Ansel, Kapil Arya, Gene D. Cooperman Dec 2010

Dmtcp: Transparent Checkpointing For Cluster Computations And The Desktop, Jason Ansel, Kapil Arya, Gene D. Cooperman

Gene D. Cooperman

DMTCP (Distributed MultiThreaded CheckPointing) is a transparent user-level checkpointing package for distributed applications. Checkpointing and restart is demonstrated for a wide range of over 20 well known applications, including MATLAB, Python, TightVNC, MPICH2, OpenMPI, and runCMS. RunCMS runs as a 680 MB image in memory that includes 540 dynamic libraries, and is used for the CMS experiment of the Large Hadron Collider at CERN. DMTCP transparently checkpoints general cluster computations consisting of many nodes, processes, and threads; as well as typical desktop applications. On 128 distributed cores (32 nodes), checkpoint and restart times are typically 2 seconds, with negligible run-time …


Cloud Computing: Strategies For Cloud Computing Adoption, Faith J. Shimba Dec 2010

Cloud Computing: Strategies For Cloud Computing Adoption, Faith J. Shimba

Faith Joel Shimba

The advent of cloud computing in recent years has sparked an interest from different IT stakeholders. This is a result of the new economic model for the IT department that cloud computing promises. The model promises to remove the need for heavy investment for limited IT resources towards renting IT resources and paying based on usage. Although, the adoption of cloud computing promises various benefits to organizations, a successful adoption requires an understanding of different dynamics and expertise in diverse domains. Currently there are inadequate guidelines for adoption and this book proposes a roadmap for cloud computing adoption called ROCCA. …


Tuning Of Power System Stabilizers Using Particle Swarm Optimization With Passive Congregation, Mahdiyeh Eslami, Hussain Shareef, Azah Mohamed, S. P Ghoshal Dec 2010

Tuning Of Power System Stabilizers Using Particle Swarm Optimization With Passive Congregation, Mahdiyeh Eslami, Hussain Shareef, Azah Mohamed, S. P Ghoshal

Dr. Mahdiyeh Eslami (مهدیه اسلامی)

No abstract provided.


Anubis: An Attestation Protocol For Distributed Context-Aware Applications, Senaka Buthpitiya, Feng-Tso Sun, Heng-Tze Chen, Patrick Tague, Martin Griss, Anind Dey Nov 2010

Anubis: An Attestation Protocol For Distributed Context-Aware Applications, Senaka Buthpitiya, Feng-Tso Sun, Heng-Tze Chen, Patrick Tague, Martin Griss, Anind Dey

Patrick Tague

Sharing sensitive context information among multiple distributed components in mobile environments introduces major security concerns. The distributed sensing, processing and actuating components of these applications can be compromised and modified or impersonated to extract private and confidential information or to inject false information. In this paper we present the Anubis protocol for remote code attestation and access control of distributed components using remote execution of trusted code. Our Anubis protocol leverages previous work in the fields of wireless sensor networks and secure web browsing. Anubis allows new components to be introduced to the environment without updating existing components. Our implementation …


A Neural Network Based Speed Control Of A Linear Induction Motor Drive, Adel A. Elbaset, Ahmed A. Hassan, Yehia S. Mohamed, T. Hiyama,, T. H. Mohamed Nov 2010

A Neural Network Based Speed Control Of A Linear Induction Motor Drive, Adel A. Elbaset, Ahmed A. Hassan, Yehia S. Mohamed, T. Hiyama,, T. H. Mohamed

Dr. Adel A. Elbaset

In this paper, a general regression neural network (GRNN) based controller is used to control the speed and thrust output of the linear induction motor drive. The field orientation principle is used to asymptotically decouple the motor speed from the secondary flux. The idea of model predictive control technique is used for the training of the proposed controller. The motivation for using this control strategy for training the GRNN based controller is to reduce the effect of the uncertainty due to motor parameters variation and load disturbance. This newly developed design strategy combines the advantage of the neural networks and …


Convolutional Interleaver For Unequal Error Protection Of Turbo Codes, Sina Vafi, Tadeusz A. Wysocki, Ian Burnett Nov 2010

Convolutional Interleaver For Unequal Error Protection Of Turbo Codes, Sina Vafi, Tadeusz A. Wysocki, Ian Burnett

Ian Burnett

This paper describes construction of a convolutional interleaver as a block interleaver and discusses its application to turbo codes with equal and unequal error protection techniques. Based on simulations, different convolutional interleaver structures suitable for turbo codes with unequal error protection capability are suggested. Finally, based on conducted simulations the best method is selected.


Closing The Gap Between The Industry And Higher Education Institutions- Case Examples From East African Region, Deogratias Harorimana Mr Nov 2010

Closing The Gap Between The Industry And Higher Education Institutions- Case Examples From East African Region, Deogratias Harorimana Mr

Dr Deogratias Harorimana

Much complained about is the quality of graduates Universities put on the labour market. Less talked about however is why knowledge institutions seems to be bad knowledge managers. In this presentation I argue that DIRECT collaborative relationship between Industry,Governments and Higher Education Institutions is a per-requisite.Good relationship is key to building such a successful knowledge transfer strategies between Industries and Educational and Research Institutions. This paper explores what makes a good Knowledge Transfer Partnership Strategy and highlights some key lessons for businesses, Universities and Government bodies. This paper was a Key note presentation to the Annual International Conference on Building …


The Kerf Toolkit For Intrusion Analysis, Javed A. Aslam, Sergey Bratus, David Kotz, Ron Peterson, Brett Tofel, Daniela Rus Nov 2010

The Kerf Toolkit For Intrusion Analysis, Javed A. Aslam, Sergey Bratus, David Kotz, Ron Peterson, Brett Tofel, Daniela Rus

Javed A. Aslam

To aid system administrators with post-attack intrusion analysis, the Kerf toolkit provides an integrated front end and powerful correlation and data-representation tools, all in one package.


On Iterative Decoding Of Two-Level Superposition Codes For Cooperative Broadcasting Based On Qpsk And 4-Pam Constellations, Robert H. Morelos-Zaragoza Nov 2010

On Iterative Decoding Of Two-Level Superposition Codes For Cooperative Broadcasting Based On Qpsk And 4-Pam Constellations, Robert H. Morelos-Zaragoza

Robert Henry Morelos-Zaragoza

This paper considers iterative decoding of two-level superposition codes used in cooperative broadcasting over wireless networks. The coding scheme consists of two low-density parity-check (LDPC) codes combined using Plotkin’s |u|u+v|-construction and provides two levels of error protection.


Improving Anti-Jamming Capability And Increasing Jamming Impact With Mobility Control, Patrick Tague Oct 2010

Improving Anti-Jamming Capability And Increasing Jamming Impact With Mobility Control, Patrick Tague

Patrick Tague

The impact of a jamming attack on wireless communication depends on a number of physical characteristics and network protocol parameters. In particular, it depends on the relative geometries of the adversarial network of jammers and the network under attack. Hence, changes in network geometry achieved through node and jammer mobility can have significant influence on the impact of a jamming attack. In this work, we investigate the use of mobility as a tool to allow both the adversarial network and the network under attack to reconfigure their geometry in an attempt to improve attack impact and protocol performance, respectively. We …


Software Engineering Issues For Mobile Application Development, Tony Wasserman Oct 2010

Software Engineering Issues For Mobile Application Development, Tony Wasserman

Tony Wasserman

This paper provides an overview of important software engineering research issues related to the development of applications that run on mobile devices. Among the topics are development processes, tools, user interface design, application portability, quality, and security.


Genetic Algorithm Based Optim-Al Sizing Of Pv-Diesel-Battery System Considering Co2 Emission And Reliability, Dr. Adel A. Elbaset, Heri Suryoatmojo, Prof. Dr. Takashi Hiyama Oct 2010

Genetic Algorithm Based Optim-Al Sizing Of Pv-Diesel-Battery System Considering Co2 Emission And Reliability, Dr. Adel A. Elbaset, Heri Suryoatmojo, Prof. Dr. Takashi Hiyama

Dr. Adel A. Elbaset

The reliability system concern and CO2 emission reduction are still the main targets of optimization problem in the hybrid generation system components. This pa- per utilizes Genetic Algorithm (GA) method to determine the optimal capacities of PV system, battery bank and diesel generator (DG) unit according to the minimum cost ob- jective functions that relate to these two factors. In this study, the cost objective function includes the annual capital cost (ACC), annual operation maintenance cost (AOM), an- nual replacement cost (ARC), annual fuel cost (AFC), annual emission cost (AEC) and annual customer damage cost (ADC). The proposed method has …


Public Consultations On Net Neutrality 2010: Usa, Eu And France, Sulan Wong, Julio Rojas Mora, Eitan Altman Sep 2010

Public Consultations On Net Neutrality 2010: Usa, Eu And France, Sulan Wong, Julio Rojas Mora, Eitan Altman

Julio Rojas-Mora

The evolution of the Internet has come to a point where almost at the same time, governments all around the world feel the need for legislation to regulate the use of the Internet. In preparing the legislation, consultations were called by various governments or by the corresponding regulation bodies. We describe in this paper the various consultations as well as the background related to the Net Neutrality question in each case. Rather than describing the answers to each consultation, which are available and which have already been analyzed, we focus on comparing the consultations and the statistical figures related to …


The Role Of Knowledge Management In The Strategic Alignment Of Information Technology With Business: An Alternative And Complementary View, Fernando Paulo Belfo Sep 2010

The Role Of Knowledge Management In The Strategic Alignment Of Information Technology With Business: An Alternative And Complementary View, Fernando Paulo Belfo

Fernando Paulo Belfo

The Information Technology (IT) team knowledge of business strategy and the organization team knowledge of information technology are critical factors in the strategic business and IT alignment (BIA). These two factors have in common precisely the importance of "knowledge". The Information Technology team lack of knowledge about business and its strategy and vice-versa should be a major concern for the organization, since this knowledge strongly affects the possibility of an appropriate strategic alignment between business and the IT. It is significantly important to create an enabling environment for the growth of shared knowledge of the business area, encouraging professional IT …


An Introduction To Virus Scanners, Umakant Mishra Aug 2010

An Introduction To Virus Scanners, Umakant Mishra

Umakant Mishra

The main functions of an anti-virus program are, (i) Virus prevention and file protection, (ii) Virus scanning and detection, (iii) Removing virus from infected files, and (iv) Recovering damaged files and objects.

An anti-virus program employs various methods to detect and remove viruses. The two popular methods of detecting viruses are signature scanning and behavior monitoring. However each of these methods has its strengths and weaknesses.

As the detection gets more sophisticated so are the virus programmers. The virus programmers also try to go one step beyond the anti-virus mechanism and create intelligent viruses which pose more and more difficult …


An Introduction To Computer Viruses, Umakant Mishra Aug 2010

An Introduction To Computer Viruses, Umakant Mishra

Umakant Mishra

The computer virus is a problem to computer users at all levels including students, home users, corporate users, system administrators, corporate managers and even the anti-virus manufacturers. The viruses are written by people with malefic intentions to trouble the innocent users.

There are many types of viruses are boot sector viruses, file viruses, worms, Trojan horses, macro viruses etc. Each of these has many different variants. The older viruses were transmitting through floppies. Some older viruses like boot sector viruses are very rare nowadays as nobody boots from floppies. The modern day viruses transmit more through networks and emails. Macro …


Methods Of Virus Detection And Their Limitations, Umakant Mishra Aug 2010

Methods Of Virus Detection And Their Limitations, Umakant Mishra

Umakant Mishra

An anti-virus program typically employs various strategies to detect and remove viruses. The popular methods of detecting virus are signature scanning, heuristic scanning and integrity checking. However each of these methods has its own strengths and weaknesses.

Signature scanning (or searching of known virus patterns) is the most common method of virus detection. But it cannot detect viruses whose signatures are not available in the virus database. The other popular method is to use a heuristic algorithm to find viruses based on common behaviors. This method can be complex, but it has the ability to detect unknown or new viruses. …


Who Said What When? Capturing The Important Moments Of A Meeting, Shoou-Jong Yu, Ted Selker Jul 2010

Who Said What When? Capturing The Important Moments Of A Meeting, Shoou-Jong Yu, Ted Selker

Ted Selker

Current meeting information capturing paradigms such as pen and paper has been found to be tedious and distractive. This paper presents CollabMeet, a mobile phone based, one screen meeting information capture system to address these issues. We also introduce a new social interaction centric recording paradigm, where only moments deemed important by meeting participants are recorded with a single click of a button. Results from our pilot experiment shows that our system positively contributes to the quality of meeting reconstruction, while being minimally-distractive to the meeting participants.


Travelrole: A Carpooling/ Physical Social Network Creator, Ted Selker, Paula Helen Saphir Jul 2010

Travelrole: A Carpooling/ Physical Social Network Creator, Ted Selker, Paula Helen Saphir

Ted Selker

This paper describes a system that extends concepts of social networking application to create a physical social network, with the extra advantage of also working to save energy. TravelRole is a system that helps people choose to use their commute time to fulfill work, educational and recreational goals. The system matches people to rides that allow them to link carpooling with a personal goal such as practicing their French, talking about rebuilding an engine, discussing religion, and so on.

TravelRole’s interface encourages people to focus on reasons they would like to get together with other people to see how these …


A Vector Based Method Of Ontology Matching, Z. Eidoon, N. Yazdani, Farhad Oroumchian Jul 2010

A Vector Based Method Of Ontology Matching, Z. Eidoon, N. Yazdani, Farhad Oroumchian

Farhad Oroumchian

Semantic interoperability is highly influenced by similarities and differences which exist between ontologies. Ontology matching as a solution for finding corresponding concepts among ontologies has emerged to facilitate semantic based negotiations of applications. This paper presents a method of ontology matching which is based on vectorizing ontologies and estimating their similarity degree. A post processing with two heuristic rules also has been employed to improve the results. The proposed method is successfully applied to the test suit of Ontology Alignment Evaluation Initiative 2005 [10] and compared to results obtained by other methods. In general the preliminary results are encouraging and …


Clusid: A Clustering Scheme For Intrusion Detection, Improved By Information Theory, R. Shokri, Farhad Oroumchian, N. Yazdani Jul 2010

Clusid: A Clustering Scheme For Intrusion Detection, Improved By Information Theory, R. Shokri, Farhad Oroumchian, N. Yazdani

Farhad Oroumchian

Security is a big issue for all networks in any enterprise environment. Many solutions have been proposed to secure the network infrastructure and communication over the Internet. Intrusion Detection Systems with many different techniques such as data mining approaches are employed to maximize the detection rate of intrusions while reducing false alarm rate. For instance, many clustering techniques are recommended which segregate normal and abnormal data in IDSs. Clustering methods put emphasis on finding differences and similarities of traffic sessions to categorize each one in its corresponding groups. These groups are represented by their assigned labels. Later, these labels are …