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A Top-Down Structured Programming Technique for Mini-Computers

Description: This paper reviews numerous theoretical results on control structures and demonstrates their practical examples. This study deals with the design of run-time support routines by using top-down structured programming technique. A number of examples are given as illustration of this method. In conclusion, structured programming has proved to be an important methodology for systematic program design and development.
Date: May 1978
Creator: Wu, Chin-yi Robert
Partner: UNT Libraries

Software and Hardware Interface of a VOTRAX Terminal for the Fairchild F24 Computer

Description: VOTRAX is a commercially available voice synthesizer for use with a digital computer. This thesis describes the design and implementation of a VOTRAX terminal for use with the Fairchild F24 computer. Chapters of the thesis consider the audio response technology, some characteristics of Phonetic English Speech, configuration of hardware, and describe the PHONO computer program which was developed. The last chapter discusses the advantages of the VOTRAX voice synthesizer and proposes a future version of the system with a time-sharing host computer.
Date: May 1979
Creator: Wu, Chun Hsiang
Partner: UNT Libraries

Computer Analysis of Amino Acid Chromatography

Description: The problem with which this research was done was that of applying the IBM360 computer to the analysis of waveforms from a Beckman model 120C liquid chromatograph. Software to interpret these waveforms was written in the PLl language. For a control run, input to the computer consisted of a digital tape containing the raw results of the chromatograph run. Output consisted of several graphs and charts giving the results of the analysis. In addition, punched output was provided which gave the name of each amino acid, its elution time and color constant. These punched cards were then input to the computer as input to the experimental run, along with the raw data on the digital tape. From the known amounts of amino acids in the control run and the ratio of control to experimental peak area, the amino acids of the unknown were quantified. The resulting programs provided a complete and easy to use solution to the problem of chromatographic data analysis.
Date: May 1978
Creator: Hayes, Michael D.
Partner: UNT Libraries

The enhancement of machine translation for low-density languages using Web-gathered parallel texts.

Description: The majority of the world's languages are poorly represented in informational media like radio, television, newspapers, and the Internet. Translation into and out of these languages may offer a way for speakers of these languages to interact with the wider world, but current statistical machine translation models are only effective with a large corpus of parallel texts - texts in two languages that are translations of one another - which most languages lack. This thesis describes the Babylon project which attempts to alleviate this shortage by supplementing existing parallel texts with texts gathered automatically from the Web -- specifically targeting pages that contain text in a pair of languages. Results indicate that parallel texts gathered from the Web can be effectively used as a source of training data for machine translation and can significantly improve the translation quality for text in a similar domain. However, the small quantity of high-quality low-density language parallel texts on the Web remains a significant obstacle.
Date: December 2007
Creator: Mohler, Michael Augustine Gaylord
Partner: UNT Libraries

Automated Syndromic Surveillance using Intelligent Mobile Agents

Description: Current syndromic surveillance systems utilize centralized databases that are neither scalable in storage space nor in computing power. Such systems are limited in the amount of syndromic data that may be collected and analyzed for the early detection of infectious disease outbreaks. However, with the increased prevalence of international travel, public health monitoring must extend beyond the borders of municipalities or states which will require the ability to store vasts amount of data and significant computing power for analyzing the data. Intelligent mobile agents may be used to create a distributed surveillance system that will utilize the hard drives and computer processing unit (CPU) power of the hosts on the agent network where the syndromic information is located. This thesis proposes the design of a mobile agent-based syndromic surveillance system and an agent decision model for outbreak detection. Simulation results indicate that mobile agents are capable of detecting an outbreak that occurs at all hosts the agent is monitoring. Further study of agent decision models is required to account for localized epidemics and variable agent movement rates.
Date: December 2007
Creator: Miller, Paul
Partner: UNT Libraries

System and Methods for Detecting Unwanted Voice Calls

Description: Voice over IP (VoIP) is a key enabling technology for the migration of circuit-switched PSTN architectures to packet-based IP networks. However, this migration is successful only if the present problems in IP networks are addressed before deploying VoIP infrastructure on a large scale. One of the important issues that the present VoIP networks face is the problem of unwanted calls commonly referred to as SPIT (spam over Internet telephony). Mostly, these SPIT calls are from unknown callers who broadcast unwanted calls. There may be unwanted calls from legitimate and known people too. In this case, the unwantedness depends on social proximity of the communicating parties. For detecting these unwanted calls, I propose a framework that analyzes incoming calls for unwanted behavior. The framework includes a VoIP spam detector (VSD) that analyzes incoming VoIP calls for spam behavior using trust and reputation techniques. The framework also includes a nuisance detector (ND) that proactively infers the nuisance (or reluctance of the end user) to receive incoming calls. This inference is based on past mutual behavior between the calling and the called party (i.e., caller and callee), the callee's presence (mood or state of mind) and tolerance in receiving voice calls from the caller, and the social closeness between the caller and the callee. The VSD and ND learn the behavior of callers over time and estimate the possibility of the call to be unwanted based on predetermined thresholds configured by the callee (or the filter administrators). These threshold values have to be automatically updated for integrating dynamic behavioral changes of the communicating parties. For updating these threshold values, I propose an automatic calibration mechanism using receiver operating characteristics curves (ROC). The VSD and ND use this mechanism for dynamically updating thresholds for optimizing their accuracy of detection. In addition to unwanted calls ...
Date: December 2007
Creator: Kolan, Prakash
Partner: UNT Libraries

High Performance Architecture using Speculative Threads and Dynamic Memory Management Hardware

Description: With the advances in very large scale integration (VLSI) technology, hundreds of billions of transistors can be packed into a single chip. With the increased hardware budget, how to take advantage of available hardware resources becomes an important research area. Some researchers have shifted from control flow Von-Neumann architecture back to dataflow architecture again in order to explore scalable architectures leading to multi-core systems with several hundreds of processing elements. In this dissertation, I address how the performance of modern processing systems can be improved, while attempting to reduce hardware complexity and energy consumptions. My research described here tackles both central processing unit (CPU) performance and memory subsystem performance. More specifically I will describe my research related to the design of an innovative decoupled multithreaded architecture that can be used in multi-core processor implementations. I also address how memory management functions can be off-loaded from processing pipelines to further improve system performance and eliminate cache pollution caused by runtime management functions.
Date: December 2007
Creator: Li, Wentong
Partner: UNT Libraries

FORTRAN Optimizations at the Source Code Level

Description: This paper discusses FORTRAN optimizations that the user can perform manually at the source code level to improve object code performance. It makes use of descriptive examples within the text of the paper for explanatory purposes. The paper defines key areas in writing a FORTRAN program and recommends ways to improve efficiency in these areas.
Date: August 1977
Creator: Barber, Willie D.
Partner: UNT Libraries

Execution Time Analysis through Software Monitors

Description: The analysis of an executing program and the isolation of critical code has been a problem since the first program was written. This thesis examines the process of program analysis through the use of a software monitoring system. Since there is a trend toward structured languages a subset of PL/I was developed t~o exhibit source statement monitoring and costing techniques. By filtering a PL/W program through a preorocessor which determines the cost of source statements and inserts monitoring code, a post-execution analysis of the program can be obtained. This analysis displays an estimated time cost for each source statements the number of times the statement w3s executed, and the product of these values. Additionally, a bar graph is printed in order to quickly locate very active code.
Date: December 1977
Creator: Whistler, Wayne C.
Partner: UNT Libraries

An Implementation of the IEEE Standard for Binary Floating-Point Arithmetic for the Motorola 6809 Microprocessor

Description: This thesis describes a software implementation of the IEEE Floating-Point Standard (IEEE Task P754), which is believed to be an effective system for reliable, accurate computer arithmetic. The standard is implemented as a set of procedures written in Motorola 6809 assembly language. Source listings of the procedures are contained in appendices.
Date: August 1983
Creator: Rosenblum, David Samuel
Partner: UNT Libraries

Generating Machine Code for High-Level Programming Languages

Description: The purpose of this research was to investigate the generation of machine code from high-level programming language. The following steps were undertaken: 1) Choose a high-level programming language as the source language and a computer as the target computer. 2) Examine all stages during the compiling of a high-level programming language and all data sets involved in the compilation. 3) Discover the mechanism for generating machine code and the mechanism to generate more efficient machine code from the language. 3) Construct an algorithm for generating machine code for the target computer. The results suggest that compiler is best implemented in a high-level programming language, and that SCANNER and PARSER should be independent of target representations, if possible.
Date: December 1976
Creator: Chao, Chia-Huei
Partner: UNT Libraries

Computerized Analysis of Radiograph Images of Embedded Objects as Applied to Bone Location and Mineral Content Measurement

Description: This investigation dealt with locating and measuring x-ray absorption of radiographic images. The methods developed provide a fast, accurate, minicomputer control, for analysis of embedded objects. A PDP/8 computer system was interfaced with a Joyce Loebl 3CS Microdensitometer and a Leeds & Northrup Recorder. Proposed algorithms for bone location and data smoothing work on a twelve-bit minicomputer. Designs of a software control program and operational procedure are presented. The filter made wedge and limb scans monotonic from minima to maxima. It was tested for various convoluted intervals. Ability to resmooth the same data in multiple passes was tested. An interval size of fifteen works well in one pass.
Date: August 1976
Creator: Buckner, Richard L.
Partner: UNT Libraries

A Computer Algorithm for Synthetic Seismograms

Description: Synthetic seismograms are a computer-generated aid in the search for hydrocarbons. Heretofore the solution has been done by z-transforms. This thesis presents a solution based on the method of finite differences. The resulting algorithm is fast and compact. The method is applied to three variations of the problem, all three are reduced to the same approximating equation, which is shown to be optimal, in that grid refinement does not change it. Two types of algorithms are derived from the equation. The number of obvious multiplications, additions and subtractions of each is analyzed. Critical section of each requires one multiplication, two additions and two subtractions. Four sample synthetic seismograms are shown. Implementation of the new algorithm runs twice as fast as previous computer program.
Date: August 1977
Creator: Isaacson, James
Partner: UNT Libraries

Using Reinforcement Learning in Partial Order Plan Space

Description: Partial order planning is an important approach that solves planning problems without completely specifying the orderings between the actions in the plan. This property provides greater flexibility in executing plans; hence making the partial order planners a preferred choice over other planning methodologies. However, in order to find partially ordered plans, partial order planners perform a search in plan space rather than in space of world states and an uninformed search in plan space leads to poor efficiency. In this thesis, I discuss applying a reinforcement learning method, called First-visit Monte Carlo method, to partial order planning in order to design agents which do not need any training data or heuristics but are still able to make informed decisions in plan space based on experience. Communicating effectively with the agent is crucial in reinforcement learning. I address how this task was accomplished in plan space and the results from an evaluation of a blocks world test bed.
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Date: May 2006
Creator: Ceylan, Hakan
Partner: UNT Libraries

Evaluating the Scalability of SDF Single-chip Multiprocessor Architecture Using Automatically Parallelizing Code

Description: Advances in integrated circuit technology continue to provide more and more transistors on a chip. Computer architects are faced with the challenge of finding the best way to translate these resources into high performance. The challenge in the design of next generation CPU (central processing unit) lies not on trying to use up the silicon area, but on finding smart ways to make use of the wealth of transistors now available. In addition, the next generation architecture should offer high throughout performance, scalability, modularity, and low energy consumption, instead of an architecture that is suitable for only one class of applications or users, or only emphasize faster clock rate. A program exhibits different types of parallelism: instruction level parallelism (ILP), thread level parallelism (TLP), or data level parallelism (DLP). Likewise, architectures can be designed to exploit one or more of these types of parallelism. It is generally not possible to design architectures that can take advantage of all three types of parallelism without using very complex hardware structures and complex compiler optimizations. We present the state-of-art architecture SDF (scheduled data flowed) which explores the TLP parallelism as much as that is supplied by that application. We implement a SDF single-chip multiprocessor constructed from simpler processors and execute the automatically parallelizing application on the single-chip multiprocessor. SDF has many desirable features such as high throughput, scalability, and low power consumption, which meet the requirements of the next generation of CPU design. Compared with superscalar, VLIW (very long instruction word), and SMT (simultaneous multithreading), the experiment results show that for application with very little parallelism SDF is comparable to other architectures, for applications with large amounts of parallelism SDF outperforms other architectures.
Date: December 2004
Creator: Zhang, Yuhua
Partner: UNT Libraries

Optimal Access Point Selection and Channel Assignment in IEEE 802.11 Networks

Description: Designing 802.11 wireless networks includes two major components: selection of access points (APs) in the demand areas and assignment of radio frequencies to each AP. Coverage and capacity are some key issues when placing APs in a demand area. APs need to cover all users. A user is considered covered if the power received from its corresponding AP is greater than a given threshold. Moreover, from a capacity standpoint, APs need to provide certain minimum bandwidth to users located in the coverage area. A major challenge in designing wireless networks is the frequency assignment problem. The 802.11 wireless LANs operate in the unlicensed ISM frequency, and all APs share the same frequency. As a result, as 802.11 APs become widely deployed, they start to interfere with each other and degrade network throughput. In consequence, efficient assignment of channels becomes necessary to avoid and minimize interference. In this work, an optimal AP selection was developed by balancing traffic load. An optimization problem was formulated that minimizes heavy congestion. As a result, APs in wireless LANs will have well distributed traffic loads, which maximize the throughput of the network. The channel assignment algorithm was designed by minimizing channel interference between APs. The optimization algorithm assigns channels in such a way that minimizes co-channel and adjacent channel interference resulting in higher throughput.
Date: December 2004
Creator: Park, Sangtae
Partner: UNT Libraries

Peptide-based hidden Markov model for peptide fingerprint mapping.

Description: Peptide mass fingerprinting (PMF) was the first automated method for protein identification in proteomics, and it remains in common usage today because of its simplicity and the low equipment costs for generating fingerprints. However, one of the problems with PMF is its limited specificity and sensitivity in protein identification. Here I present a method that shows potential to significantly enhance the accuracy of peptide mass fingerprinting, using a machine learning approach based on a hidden Markov model (HMM). This method is applied to improve differentiation of real protein matches from those that occur by chance. The system was trained using 300 examples of combined real and false-positive protein identification results, and 10-fold cross-validation applied to assess model discrimination. The model can achieve 93% accuracy in distinguishing correct and real protein identification results versus false-positive matches. The receiver operating characteristic (ROC) curve area for the best model was 0.833.
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Date: December 2004
Creator: Yang, Dongmei
Partner: UNT Libraries

Voting Operating System (VOS)

Description: The electronic voting machine (EVM) plays a very important role in a country where government officials are elected into office. Throughout the world, a specific operating system that tends to the specific requirement of the EVM does not exist. Existing EVM technology depends upon the various operating systems currently available, thus ignoring the basic needs of the system. There is a compromise over the basic requirements in order to develop the systems on the basis on an already available operating system, thus having a lot of scope for error. It is necessary to know the specific details of the particular device for which the operating system is being developed. In this document, I evaluate existing EVMs and identify flaws and shortcomings. I propose a solution for a new operating system that meets the specific requirements of the EVM, calling it Voting Operating System (VOS, pronounced 'voice'). The identification technique can be simplified by using the fingerprint technology that determines the identity of a person based on two fingerprints. I also discuss the various parts of the operating system that have to be implemented that can tend to all the basic requirements of an EVM, including implementation of the memory manager, process manager and file system of the proposed operating system.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: December 2004
Creator: Venkatadusumelli, Kiran
Partner: UNT Libraries

Adaptive Planning and Prediction in Agent-Supported Distributed Collaboration.

Description: Agents that act as user assistants will become invaluable as the number of information sources continue to proliferate. Such agents can support the work of users by learning to automate time-consuming tasks and filter information to manageable levels. Although considerable advances have been made in this area, it remains a fertile area for further development. One application of agents under careful scrutiny is the automated negotiation of conflicts between different user's needs and desires. Many techniques require explicit user models in order to function. This dissertation explores a technique for dynamically constructing user models and the impact of using them to anticipate the need for negotiation. Negotiation is reduced by including an advising aspect to the agent that can use this anticipation of conflict to adjust user behavior.
Date: December 2004
Creator: Hartness, Ken T. N.
Partner: UNT Libraries

Automated Defense Against Worm Propagation.

Description: Worms have caused significant destruction over the last few years. Network security elements such as firewalls, IDS, etc have been ineffective against worms. Some worms are so fast that a manual intervention is not possible. This brings in the need for a stronger security architecture which can automatically react to stop worm propagation. The method has to be signature independent so that it can stop new worms. In this thesis, an automated defense system (ADS) is developed to automate defense against worms and contain the worm to a level where manual intervention is possible. This is accomplished with a two level architecture with feedback at each level. The inner loop is based on control system theory and uses the properties of PID (proportional, integral and differential controller). The outer loop works at the network level and stops the worm to reach its spread saturation point. In our lab setup, we verified that with only inner loop active the worm was delayed, and with both loops active we were able to restrict the propagation to 10% of the targeted hosts. One concern for deployment of a worm containment mechanism was degradation of throughput for legitimate traffic. We found that with proper intelligent algorithm we can minimize the degradation to an acceptable level.
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Date: December 2005
Creator: Patwardhan, Sudeep
Partner: UNT Libraries

3GPP Long Term Evolution LTE Scheduling

Description: Future generation cellular networks are expected to deliver an omnipresent broadband access network for an endlessly increasing number of subscribers. Long term Evolution (LTE) represents a significant milestone towards wireless networks known as 4G cellular networks. A key feature of LTE is the implementation of enhanced Radio Resource Management (RRM) mechanism to improve the system performance. The structure of LTE networks was simplified by diminishing the number of the nodes of the core network. Also, the design of the radio protocol architecture is quite unique. In order to achieve high data rate in LTE, 3rd Generation Partnership Project (3GPP) has selected Orthogonal Frequency Division Multiplexing (OFDM) as an appropriate scheme in terms of downlinks. However, the proper scheme for an uplink is the Single-Carrier Frequency Domain Multiple Access due to the peak-to-average-power-ratio (PAPR) constraint. LTE packet scheduling plays a primary role as part of RRM to improve the system’s data rate as well as supporting various QoS requirements of mobile services. The major function of the LTE packet scheduler is to assign Physical Resource Blocks (PRBs) to mobile User Equipment (UE). In our work, we formed a proposed packet scheduler algorithm. The proposed scheduler algorithm acts based on the number of UEs attached to the eNodeB. To evaluate the proposed scheduler algorithm, we assumed two different scenarios based on a number of UEs. When the number of UE is lower than the number of PRBs, the UEs with highest Channel Quality Indicator (CQI) will be assigned PRBs. Otherwise, the scheduler will assign PRBs based on a given proportional fairness metric. The eNodeB’s throughput is increased when the proposed algorithm was implemented.
Date: December 2013
Creator: Alotaibi, Sultan
Partner: UNT Libraries

A Minimally Supervised Word Sense Disambiguation Algorithm Using Syntactic Dependencies and Semantic Generalizations

Description: Natural language is inherently ambiguous. For example, the word "bank" can mean a financial institution or a river shore. Finding the correct meaning of a word in a particular context is a task known as word sense disambiguation (WSD), which is essential for many natural language processing applications such as machine translation, information retrieval, and others. While most current WSD methods try to disambiguate a small number of words for which enough annotated examples are available, the method proposed in this thesis attempts to address all words in unrestricted text. The method is based on constraints imposed by syntactic dependencies and concept generalizations drawn from an external dictionary. The method was tested on standard benchmarks as used during the SENSEVAL-2 and SENSEVAL-3 WSD international evaluation exercises, and was found to be competitive.
Date: December 2005
Creator: Faruque, Md. Ehsanul
Partner: UNT Libraries

An Interpreter for the Basic Programming Language

Description: In this thesis, the first chapter provides the general description of this interpreter. The second chapter contains a formal definition of the syntax of BASIC along with an introduction to the semantics. The third chapter contains the design of data structure. The fourth chapter contains the description of algorithms along with stages for testing the interpreter and the design of debug output. The stages and actions-are represented internally to the computer in tabular forms. For statement parsing working syntax equations are established. They serve as standards for the conversion of source statements into object pseudocodes. As the statement is parsed for legal form, pseudocodes for this statement are created. For pseudocode execution, pseudocodes are represented internally to the computer in tabular forms.
Date: May 1975
Creator: Chang, Min-Jye S.
Partner: UNT Libraries

Information Storage and Retrieval Systems

Description: This thesis describes the implementation of a general purpose personal information storage and retrieval system. Chapter one contains an introduction to information storage and retrieval. Chapter two contains a description of the features a useful personal information retrieval system should contain. This description forms the basis for the implementation of the personal information storage and retrieval system described in chapter three. The system is implemented in UCSD Pascal on an Apple II microcomputer.
Date: May 1983
Creator: Creech, Teresa Adams
Partner: UNT Libraries