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

Computer Engineering Commons

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

Articles 1 - 14 of 14

Full-Text Articles in Computer Engineering

Relational Neighborhood Inverse Consistency For Constraint Satisfaction: A Structure-Based Approach For Adjusting Consistency & Managing Propagation, Robert J. Woodward Dec 2011

Relational Neighborhood Inverse Consistency For Constraint Satisfaction: A Structure-Based Approach For Adjusting Consistency & Managing Propagation, Robert J. Woodward

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Freuder and Elfe [1996] introduced Neighborhood Inverse Consistency (NIC) as a local consistency property defined on the values in the variables' domains of a Constraint Satisfaction Problem (CSP). Debruyne and Bessiere [2011] showed that enforcing NIC on binary CSPs is ineffective on sparse graph and too costly on dense graphs. In this thesis, we propose Relational Neighborhood Inverse Consistency (RNIC), an extension of NIC defined as a local consistency property on the tuples of the relations of a CSP. We characterize RNIC for both binary and non-binary CSPs, and propose an algorithm for enforcing it whose complexity is bounded by …


Location Cheating: A Security Challenge To Location-Based Social Network Services, Mai Ren Dec 2011

Location Cheating: A Security Challenge To Location-Based Social Network Services, Mai Ren

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Location-based mobile social network services such as Foursquare and Gowalla have grown exponentially over the past several years. These location-based services utilize the geographical position to enrich user experiences in a variety of contexts, including location-based searching and location-based mobile advertising. To attract more users, the location-based mobile social network services provide real-world rewards to the user, when a user checks in at a certain venue or location. This gives incentives for users to cheat on their locations.

In this thesis, we investigate the threat of location cheating attacks, find the root cause of the vulnerability, and outline the possible …


Efficient Traffic Crash And Snow Complaint Gis System, Anthony B. Ngo Nov 2011

Efficient Traffic Crash And Snow Complaint Gis System, Anthony B. Ngo

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

We describe the design and implementation of a traffic crash and snow complaint GIS system developed for the Lincoln Public Works department. We also describe a novel geocoding algorithm that was used to move data from the older Criminal Justice Information System, which is a relational database, to the new GIS system. In addition, we describe the implementation of several indexing algorithms that enable the system to efficiently answer rectangular range queries and queries about the relative locations of moving objects. Finally, in many applications (on-line analysis or mobile GIS), we need to execute spatial query efficiently (fast and small), …


Classification For Mass Spectra And Comprehensive Two-Dimensional Chromatograms, Xue Tian Aug 2011

Classification For Mass Spectra And Comprehensive Two-Dimensional Chromatograms, Xue Tian

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Mass spectra contain characteristic information regarding the molecular structure and properties of compounds. The mass spectra of compounds from the same chemically related group are similar. Classification is one of the fundamental methodologies for analyzing mass spectral data. The primary goals of classification are to automatically group compounds based on their mass spectra, to find correlation between the properties of compounds and their mass spectra, and to provide a positive identification of unknown compounds.

This dissertation presents a new algorithm for the classification of mass spectra, the most similar neighbor with a probability-based spectrum similarity measure (MSN-PSSM). Experimental results demonstrate …


Molecular Dynamics Simulation Based On Hadoop Mapreduce, Chen He Jul 2011

Molecular Dynamics Simulation Based On Hadoop Mapreduce, Chen He

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Molecular Dynamics (MD) simulation is a computationally intensive application used in multiple fields. It can exploit a distributed environment due to inherent computational parallelism. However, most of the existing implementations focus on performance enhancement. They may not provide fault-tolerance for every time-step.

MapReduce is a framework first proposed by Google for processing huge amounts of data in a distributed environment. The simplicity of the programming model and fault- tolerance for node failure during run-time make it very popular not only for commercial applications but also in scientific computing.

In this thesis, we develop a novel communication-free and each time-step fault- …


Real-Time Divisible Load Scheduling For Cluster Computing, Anwar Mamat Jul 2011

Real-Time Divisible Load Scheduling For Cluster Computing, Anwar Mamat

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Cluster computing has become an important paradigm for solving large-scale problems. However, as the size of a cluster increases, so does the complexity of resource management and maintenance. Therefore, automated performance control and re- source management are expected to play critical roles in sustaining the evolution of cluster computing. The current cluster scheduling practice is similar in sophistication to early supercomputer batch scheduling algorithms, and no consideration is given to desired quality-of-service (QoS) attributes. To fully avail the power of computational clusters, new scheduling algorithms that provides high performance, QoS assurance, fault-tolerance, energy savings and streamlined management of the cluster …


A Reservation-Based Smart Parking System, Hongwei Wang Jul 2011

A Reservation-Based Smart Parking System, Hongwei Wang

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

In metropolitan areas, parking management influences drivers search time and cost for parking spaces, parking revenue, and traffic congestion. The wide deployment of wireless parking meters with sensing and communications capabilities allows the parking authority to monitor the state of each parking space in real time and optimize the parking management.

In this thesis, we study state-of-the-art parking policies in smart parking systems, and show that the smart parking system needs to be "smarter". Our design goals of the smart parking systems include: (1) simplify the operations of parking systems, (2) improve drivers' satisfaction, (3) increase parking revenue, and (4) …


Campus Grids: A Framework To Facilitate Resource Sharing, Derek J. Weitzel May 2011

Campus Grids: A Framework To Facilitate Resource Sharing, Derek J. Weitzel

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

It is common at research institutions to maintain multiple clusters. These might fulfill different needs and policies, or represent different owners or generations of hard- ware. Many of these clusters are under utilized while researchers at other departments may require these resources. This may be solved by linking clusters with grid mid- dleware. This thesis describes a distributed high throughput computing framework to link clusters without changing security or execution environments. The framework initially keeps jobs local to the submitter, overflowing if necessary to the campus, and regional grid. The framework is implemented spanning two campuses at the Holland Computing …


Ontology For Psychophysiological Dysregulation Of Anger/Aggression, Swathi Vasanthapuram May 2011

Ontology For Psychophysiological Dysregulation Of Anger/Aggression, Swathi Vasanthapuram

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

The advancement of Information Technology in the last four decades led to the use of computers in medicine. A new area called Medical Informatics has emerged. This area comprises the application of IT to healthcare with the aim of creating tools that help healthcare personnel diagnose and treat patients more accurately and efficiently. IT not only provides tools for storing, integrating, and updating patient information base but also for processing information efficiently. One of such tools is a Clinical Decision Support System. Ontologies are an integral part of clinical decision support systems because they help formalize and integrate domain knowledge. …


Protein Structure – Based Method For Identification Of Horizontal Gene Transfer In Bacteria, Swetha Billa May 2011

Protein Structure – Based Method For Identification Of Horizontal Gene Transfer In Bacteria, Swetha Billa

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Horizontal Gene Transfer is defined as the movement of genetic material from one strain of species to another. Bacteria, being an asexual organism were always believed to transfer genes vertically. But recent studies provide evidence that shows bacteria can also transfer genes horizontally.

HGT plays a major role in evolution and medicine. It is the major contributor in bacterial evolution, enabling species to acquire genes to adapt to the new environments. Bacteria are also believed to develop drug resistance to antibiotics through the phenomenon of HGT. Therefore further study of HGT and its implications is necessary to understand the effects …


Multi-Channel Peer-To-Peer Streaming Systems As Resource Allocation Problems, Miao Wang Apr 2011

Multi-Channel Peer-To-Peer Streaming Systems As Resource Allocation Problems, Miao Wang

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

In the past few years, the Internet has witnessed the success of Peer-to-Peer (P2P) streaming technology, which has attracted millions of users. More recently, commercial P2P streaming systems have begun to support multiple channels and a user in such systems is allowed to watch more than one channel at a time. We refer to such systems as multi-channel P2P streaming systems. In this dissertation, we focus on designing multi-channel P2P streaming systems with the goal of providing optimal streaming quality for all channels, termed as system-wide optimal streaming quality. Specifically, we design the systems from the perspective of how to …


Offline Optimization Of Advance Reservation Of Bandwidth Over Dynamic Circuit Networks, Pragatheeswaran Angu Apr 2011

Offline Optimization Of Advance Reservation Of Bandwidth Over Dynamic Circuit Networks, Pragatheeswaran Angu

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

E-science projects require very high-speed and reliable networks to transfer data across various destinations in the world. Dynamic Circuit Network (DCN) is a networking service to make advance reservation of bandwidth between a source and a destination in a network. In this thesis we solve the problem of advance reservation of bandwidth in next-generation wavelength-division multiplexing (WDM) networks using a simulation based approach.
We implement a greedy algorithm and a genetic algorithm in parallel, in separate threads. The request for advance reservation is processed by both but the user gets the response only from the greedy algorithm. The genetic algorithm …


Polygonal Spatial Clustering, Deepti Joshi Apr 2011

Polygonal Spatial Clustering, Deepti Joshi

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Clustering, the process of grouping together similar objects, is a fundamental task in data mining to help perform knowledge discovery in large datasets. With the growing number of sensor networks, geospatial satellites, global positioning devices, and human networks tremendous amounts of spatio-temporal data that measure the state of the planet Earth are being collected every day. This large amount of spatio-temporal data has increased the need for efficient spatial data mining techniques. Furthermore, most of the anthropogenic objects in space are represented using polygons, for example – counties, census tracts, and watersheds. Therefore, it is important to develop data mining …


Identifying Horizontal Gene Transfer Using Anomalies In Protein Structures And Sequences, Venkat Ram B. Santosh Feb 2011

Identifying Horizontal Gene Transfer Using Anomalies In Protein Structures And Sequences, Venkat Ram B. Santosh

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Genetics has traditionally focused on vertical gene transfer, which is the passing of the genetic material of an organism to its offspring. However, recent studies in genetics increased the awareness that horizontal gene transfer, which is the passing of the genetic material of an organism to another organism that is not its offspring, is also a significant phenomenon. Horizontal gene transfer is thought to play a major role in the natural evolution of bacteria, such as, when several different types of bacteria all suddenly develop the same drug resistance genes. Artificial horizontal gene transfer occurs in genetic engineering.

This thesis …