Physical Sciences and Mathematics Commons^™

Infrastructure For Performance Tuning Mpi Applications, Kathryn Marie Mohror

Dissertations and Theses

Clusters of workstations are becoming increasingly popular as a low-budget alternative for supercomputing power. In these systems,message-passing is often used to allow the separate nodes to act as a single computing machine. Programmers of such systems face a daunting challenge in understanding the performance bottlenecks of their applications. This is largely due to the vast amount of performance data that is collected, and the time and expertise necessary to use traditional parallel performance tools to analyze that data.

The goal of this project is to increase the level of performance tool support for message-passing application programmers on clusters of workstations. …

Underwater Terrain Reconstruction Using Sonar Data Taken From Multiple Vantage Points, Christopher Roman

Christopher N. Roman

No abstract provided.

Extracting User Intent In Mixed Initiative Teleoperator Control, Andrew H. Fagg, Michael Rosenstein, Robert Platt Jr., Roderic Grupen

Roderic Grupen

User fatigue is common with robot teleoperation interfaces. Mixed initiative control approaches attempt to reduce this fatigue by allowing control responsibility to be shared between the user and an intelligent control system. A critical challenge is how the user can communicate her intentions to the control system in an intuitive manner as possible. In the context of control of a humanoid robot, we propose an interface that uses the movement currently commanded by the user to assess the intended outcome. Specifically, given the observation of the motion of the teleoperated robot for a given period of time, we would like …

Spatiotemporal Databases: Models For Attracting Students To Research, Ágnes Bércesné Novák, Peter Revesz, Zsolt Tuza

CSE Conference and Workshop Papers

In higher education professors often make much effort to introduce their students to research. Unfortunately, the present standard database systems curriculum is composed of well-settled subjects that do not lead to research. The challenge is to bring the research frontier closer to students at beginner level. In this paper we describe how it can be done in the area of spatiotemporal databases. We propose a new database systems curriculum and illustrate its benefits by mentioning several highly succsesful student projects in some recent experimental introductory database systems courses that followed the new curriculum.

Efficient Customizable Middleware, Ravi Pratap Maddimsetty

All Computer Science and Engineering Research

The rather large feature set of current Distributed Object Computing (DOC) middleware can be a liability for certain applications which have a need for only a certain subset of these features but have to suffer performance degradation and code bloat due to all the present features. To address this concern, a unique approach to building fully customizable middleware was undertaken in FACET, a CORBA event channel written using AspectJ. FACET consists of a small, essential core that represents the basic structure and functionality of an event channel into which additional features are woven using aspects so that the resulting event …

Resource Configuration And Network Design In Extensible Networks, Sumi Y. Choi

All Computer Science and Engineering Research

The goal of packet-switched networks has conventionally been delivering data to users. This concept is changing rapidly as current technologies make it possible to build network processing engines that apply intermediary services to data traffic. This trend introduces an extensive range of ways to develop and operate applications by allowing processing services customized for applications' needs at intermediate network users, as it can relieve individuals from the need to acquire, install, and maintain software in end systems to perform required functions. As such network services become more widely used, it will become increasingly important for service providers to have effective …

An Iterative Beam Search Algorithm For Degenerate Primer Selection, Richard Souvenir

All Computer Science and Engineering Research

Single Nucleotide Polymorphism (SNP) Genotyping is an important molecular genetics process in the early stages of producing results that will be useful in the medical field. Due to inherent complexities in DNA manipulation and analysis, many different methods have been proposed for a standard assay. One of the proposed techniques for performing SNP Genotyping requires amplifying regions of DNA surrounding a large number of SNP loci. In order to automate a portion of this particular method, it is necessary to select a set of primers for the experiment. Selecting these primers can be formulated as the Multiple Degenerate Primer Design …

Constraint Datalog In Trust Management, Scot Anderson

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

Constraint Datalog holds an increasing role in Trust Management. We discuss several Trust Management systems and give a description of the environment and requirements for Trust Management. Constraint Datalog using addition constraints and approximation theory provides an expressive semantic with which to describe security policies for credentials, delegations and authorizations. Approximation theory allows halting in Constraint Datalog over addition constraints. We use the decision problem of Diophantine equations to show that Constraint Datalog over addition constraints is complete. Combining these two concepts provides an approximately complete, safe language. The problem of constant additions to closed languages provides reasons for using …

Using Dynamic Optimization For Control Of Real Rate Cpu Resource Management Applications, Varin Vahia, Ashvin Goel, David Steere, Jonathan Walpole, Molly H. Shor

Computer Science Faculty Publications and Presentations

In this paper we design a proportional-period optimal controller for allocating CPU to real rate multimedia applications on a general-purpose computer system. We model this computer system problem in to state space form. We design a controller based on dynamic optimization LQR tracking techniques to minimize short term and long term time deviation from the current time stamp and also CPU usage. Preliminary results on an experimental set up are encouraging.

Hardware-Based Dynamic Storage Management For High-Performance And Real-Time Systems, Victor H. Lai

All Computer Science and Engineering Research

Most modern application programs depend on dynamic storage management to handle allocation and deallocation of memory. Unfortunately conventional software-based storage managers are relatively low performance due to the latency associated with accessing DRAM memory. Consequently, developers of programs with very specialized memory requirements, such a real-time systems, often choose to manage memory manually at the application-code level. This practice can greatly increase performance but it can also significantly complicate the development process. In this thesis we present the design, VHDL implementation and performance evaluation of hardware-based storage manager called the Optimized Hardware Estranged Buddy System (OHEBS). The OHEBS implements four …

Storage Coalescing, Delvin C. Defoe

All Computer Science and Engineering Research

Typically, when a program executes, it creates objects dynamically and requests storage for its objects from the underlying storage allocator. The patterns of such requests can potentially lead to internal fragmentation as well as external fragmentation. Internal fragmentation occurs when the storage allocator allocates a contiguous block of storage to a program, but the program uses only a fraction of that block to satisfy a request. The unused portion of that block is wasted since the allocator cannot use it to satisfy a subsequent allocation request. External fragmentation, on the other hand, concerns chunks of memory that reside between allocated …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 2, October 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Cs 790-01: Introduction To Parallel Algorithms, Natsuhiko Futamura

Computer Science & Engineering Syllabi

Low-cost parallel computers such as PC clusters are becoming available, and many previously unsolvable problems can be solved using such computers. However, designing algorithms that perform well on parallel computers is often challenging. The focus of this course is on learning how to design algorithms for parallel computers and how to evaluate them.

Examination Of Focused Beam Propagation Through A Finite Non-Reciprocal Planar Chiral Slab Using Complex Fresnel Coefficients And Dual Transforms, Monish Ranjan Chatterjee, Sumit Nema, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Recently, uniform plane wave propagation across a nonchiral-chiral interface was examined via the development of appropriate Fresnel coefficients. In this extension, propagation of focused uniform and profiled beams through a finite, planar nonreciprocal chiral slab is investigated using complex Fresnel coefficients via angular plane wave decomposition and dual transforms.

Unidirectional Cordic For Efficient Computation Of Trigonometric And Hyperbolic Functions, Satish Ravichandran

Electrical & Computer Engineering Theses & Dissertations

CORDIC (Coordinate Rotation Digital Computer) is an iterative algorithm to compute values of trigonometric, logarithmic and transcendental functions by performing vector rotations, which can be implemented with only shift and add operations in a digital system. CORDIC algorithms are extensively used in the areas of digital signal processing, digital image processing and artificial neural networks. A new technique, named unidirectional CORDIC, for efficient computation of trigonometric and hyperbolic functions is presented in this thesis. In the conventional CORDIC algorithm, the vector rotations are performed in both clockwise and counterclockwise directions, but in the unidirectional CORDIC the vectors are rotated only …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 1, September 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Optical And Acoustic Habitat Characterization With The Seabed Auv, Hanumant Singh, Ryan Eustice, Oscar Pizarro, Christopher Roman

Christopher N. Roman

The Seabed AUV is an Autonomous Underwater Vehicle (AUV) built to serve as a readily available and operationally simple tool for high resolution imaging. It is a hover-capable vehicle that performs optical sensing with a 12 bit 1280/spl times/1024 CCD camera and acoustic high resolution mapping using an MST 300 kHz sidescan and a 675 kHz pencil beam bathymetric sonar. The AUV has been designed for operations from small vessels with minimal support equipment. It has an operational depth of 2000 meters and at 1 m/s can run for up to 10 hours. In this paper we report on the …

Secure Remote Control And Configuration Of Fpx Platform In Gigabit Ethernet Environment, Haoyu Song

All Computer Science and Engineering Research

Because of its flexibility and high performance, reconfigurable logic functions implemented on the Field-programmable Port Extender (FPX ) are well suited for implementing network processing such as packet classification, filtering and intrusion detection functions. This project focuses on two key aspects of the FPX system. One is providing a Gigabit Ethernet interface by designing logic for a FPGA which is located on a line card. Address Resolution Protocol (ARP) packets are handled in hardware and Ethernet frames are processed and transformed into cells suitable for standard FPX application. The other effort is to provide a secure channel to enable remote …

Revisiting The Fresnel Coefficients For Uniform Plane Wave Propagation Across A Nonchiral, Reciprocal And Chiral, Nonreciprocal Interface, Monish Ranjan Chatterjee, Sumit Nema

Electrical and Computer Engineering Faculty Publications

The problem of EM wave propagation in non-reciprocal chiral media has been studied by several investigators. In a recent approach, a dual-transform technique has been developed to study the problem of such propagation under paraxial and slow-envelope variation conditions.

In this paper, we first outline some of the results obtained using the dual transform technique for arbitrary boundary conditions within the left boundary of a semi-infinite, non-reciprocal chiral medium for a uniform plane wave, and a fundamental Gaussian-profiled beam. Next, we explore the problem of a uniform EM wave incident at an oblique angle at an interface between a reciprocal, …

Adaptive Live Video Streaming By Priority Drop, Jie Huang, Charles Krasic, Jonathan Walpole

Computer Science Faculty Publications and Presentations

In this paper we explore the use of Priority-progress streaming (PPS) for video surveillance applications. PPS is an adaptive streaming technique for the delivery of continuous media over variable bit-rate channels. It is based on the simple idea of reordering media components within a time window into priority order before transmission. The main concern when using PPS for live video streaming is the time delay introduced by reordering. In this paper we describe how PPS can be extended to support live streaming and show that the delay inherent in the approach can be tuned to satisfy a wide range of …

A Generative Programming Framework For Adaptive Middleware, Venkita Subramonian, Christopher Gill

All Computer Science and Engineering Research

Historically, many distributed real-time and embedded (DRE) systems were developed manually from scratch, leading to stove-piped solutions that while correct in both functional and QoS properties were very expensive to develop and difficult to maintain and extend. First-generation middleware technologies such as CORBA 2.x [1], XML [2], and SOAP [3], served to shield application developers from low-level platform details, thus raising the level of abstraction at which distributed systems are developed and supporting reuse of infrastructure to amortize development costs over the lifetime of a system. However, interdependencies between services and object interfaces resulting from these programming models significantly limited …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 8, June 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Wind Gusts, Christopher Roman

Christopher N. Roman

Article that appeared in Sail magazine (ISSN: 0036-2700).

Compressed Data Structures For Recursive Flow Classification, Edward W. Spitznagel

All Computer Science and Engineering Research

High-speed packet classification is crucial to the implementation of several advanced network services and protocols; many QoS implementations, active networking platforms, and security devices (such as firewalls and intrusion-detection systems) require it. But performing classification on multiple fields, at the speed of modern networks, is known to be a difficult problem. The Recursive Flow Classification (RFC) algorithm described by Gupta and McKeown performs classification very quickly, but can require excessive storage when using thousands of rules. This paper studies a compressed representation for the tables used in RFC, trading some memory accesses for space. The compression’s efficiency can be improved …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 19, Number 7, May 2003, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Guest Editorial: Text And Web Mining, Ah-Hwee Tan, Philip S. Yu

Research Collection School Of Computing and Information Systems

Text mining and web mining are two interrelated fields that have received a lot of attention in recent years. Text mining [1, 2] is concerned with the analysis of very large document collections and the extraction of hidden knowledge from text-based data. Web mining [3] refers to the analysis and mining of all web-related data, including web content, hyperlink structure, and web access statistics.

A Performance-Driven Framework For Customizing Csp Middleware Support, Guoliang Xing

All Computer Science and Engineering Research

A Distributed Constraint Satisfaction Problem (DCSP) aims to find consistent assignments of values to a set of variables distributed on multiple nodes. Despite its simple definition, DCSPs can model a broad variety of traditional artificial intelligence problems. Furthermore, many problems found in emerging sensor-actuator networks can be formalized to DCSPs. However, due to the platform limitations of networked embedded systems such as sensor-actuators networks, building real-world applications for solving DCSPs not only requires the improved DCSP algorithms but also novel system approaches. This thesis first develops a performance-driven middleware framework for solving DCSP problems. Then the prototype system built with …

Specialized Hardware Support For Dynamic Storage Allocation, Steven M. Donahue

All Computer Science and Engineering Research

With the advent of operating systems and programming languages that can evaluate and guarantee real-time specifications, applications with real-time requirements can be authored in higher-level languages. For example, a version of Java suitable for real-time (RTSJ) has recently reached the status of a reference implementation, and it is likely that other implementations will follow. Analysis to show the feasibility of a given set of tasks must take into account their worst-case execution time, including any storage allocation or deallocation associated with those tasks. In this thesis, we present a hardware-based solution to the problem of storage allocation and (explicit) deallocation …

Using Contaminated Garbage Collection And Reference Counting Garbage Collection To Provide Automatic Storage Reclamation For Real-Time Systems, Matthew P. Hampton

All Computer Science and Engineering Research

Language support of dynamic storage management simplifies the application programming task immensely. As a result, dynamic storage allocation and garbage collection have become common in general purpose computing. Garbage collection research has led to the development of algorithms for locating program memory that is no longer in use and returning the unused memory to the run-time system for late use by the program. While many programming languages have adopted automatic memory reclamation features, this has not been the trend in Real-Time systems. Many garbage collection methods involve some form of marking the objects in memory. This marking requires time proportional …

Hashtables For Real-Time And Embedded Systems, Anand Krishnan

All Computer Science and Engineering Research

Real-time are beginning to appear in advanced, high-level programming languages such as Java. When complemented by a real-time operating system, the Real-Time Specification for Java (RTSJ) offers strong execution constraints for applications developed in Java. While the RTSJ make the basic services of Java such as storage and thread management ready for many real-time applications, the collection objects, and the rest of the application run-time library, cannot be used by RTSJ applications until their run-time properties are examined and modified as necessary to make them suitable for use by real-time applications. In this work, we examine the Hashtable collection facility …