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The Dynamics Of Growth-Factor-Modified Immune-Response To Cancer Growth: One-Dimensional Models, J. A. Adam Jan 1993

The Dynamics Of Growth-Factor-Modified Immune-Response To Cancer Growth: One-Dimensional Models, J. A. Adam

Mathematics & Statistics Faculty Publications

By characterizing the effect of tumor growth factors as deviations from normal logistic-type growth rates, the spatio-temporal dynamics for a one-dimensional model of cancer growth incorporating immune response are studied. The growth rates considered are classified respectively as normal, activated, inhibited and delay activated. The homogeneous steady states are defined by relative extrema of a ''free energy'' function V(x) for each of the above four cases. This function is of particular importance in studying the coexistence of tumoral and cancer-free steady states, and in identifying the nature (progressive or regressive) of travelling wave solutions to the nonlinear partial differential equation …


Development Of A Classification System For Computer Viruses In The Ibm Pc Environment Using The Dos Operating System, Hugh R. Browne Jan 1993

Development Of A Classification System For Computer Viruses In The Ibm Pc Environment Using The Dos Operating System, Hugh R. Browne

Theses : Honours

The threat to computers worldwide from computer viruses is increasing as new viruses and variants proliferate. Availability of virus construction tools to facilitate 'customised' virus production and wider use of more sophisticated means of evading detection, such as encryption, polymorphic transformation and memory resident 'stealth' techniques increase this problem. Some viruses employ methods to guard against their own eradication from an infected computer, whilst other viruses adopt measures to prevent disassembly of the virus for examination and analysis. Growth in computer numbers and connectivity provide a growing pool of candidate hosts for infection. Standardised and flexible systems for classification and …


Symphony: A Hardware, Operating System, And Protocol Processing Architecture For Distributed Multimedia Applications, Andreas D. Bovopoulos, R. Gopalakrishnan, Saied Hosseini Jan 1993

Symphony: A Hardware, Operating System, And Protocol Processing Architecture For Distributed Multimedia Applications, Andreas D. Bovopoulos, R. Gopalakrishnan, Saied Hosseini

All Computer Science and Engineering Research

This paper explores the architectural requirements for computers to be able to process multimedia data streams such as video and audio. The I/O subsystem is shown to be a bottleneck, and a network backplane approach is suggested to alleviate this. The need to provide end-to-end performance guarantees requires predictable performance of intra-machine communication, and a schedulable bus with reservation is proposed to achieve this. In addition this requires operating system (OS) mechanisms to negotiate and enforce QoS requirements of applications. A real-time microkernel executive is proposed for each autonomous unit. Requirements for real-time microkernel exeutive is proposed for each autonomous …


Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr. Jan 1993

Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr.

Theses and Dissertations

The Air Force Institute of Technology is continuing research in the Virtual Cockpit. The Virtual Cockpit makes use of high performance graphics workstations, Virtual Environment technology, and Distributed Interactive Simulation network protocols to create a flight simulator based on the capabilities of the McDonnell Douglas F-15E Strike Eagle. The work presented in this thesis focuses on the design and implementation issues for integrating a weapons delivery capability. Weapons simulated include: RADAR and IR guided air- to-air missiles, gravity and precision guided bombs, and a 20mm cannon. Virtual Environment displays used include: color NTSC and monochrome high resolution helmet mounted displays …


Ada Implementation Of An Object Data Repository, Stephen P. Perucca Dec 1992

Ada Implementation Of An Object Data Repository, Stephen P. Perucca

Theses and Dissertations

The many benefits of object-oriented software development such as encapsulation and extendibility have inspired numerous models of the object- oriented paradigm. Rumbaugh's Object Modeling Technique (OMT) is an object- oriented model that uses three submodels. The object, dynamic, and functional submodels of the OMT describe the data, behavioral, and processing aspects of a system by using entity-relationship, state-transition, and data flow models. Cross-links relate how the three submodels tie together. Two metamodels (models of models) of the OMT are developed using the OMT methodology and notation. The essential data elements of the OMT are abstracted into a data metamodel, and …


Face Recognition With Neural Networks, Dennis L. Krepp Dec 1992

Face Recognition With Neural Networks, Dennis L. Krepp

Theses and Dissertations

This study investigated neural networks for face verification and classification. The research concentrated on developing a neural network based feature extractor and/or classifier to perform authorized user verification in a realistic work environment. Recognition accuracy, system assumptions, training time, and execution time were analyzed to determine the feasibility of a neural network approach. Data was collected using a camcorder and two segmentation schemes: manual segmentation and motion-based, automatic segmentation. Data consisted of over 2000. 32x32 pixel, 8 bit gray scale images of 52 subjects; each subject had two to ten days worth of images collected. Several training and test sets …


Automated Logistics Information Systems: A Case Study, James E. Hogue Dec 1992

Automated Logistics Information Systems: A Case Study, James E. Hogue

Theses and Dissertations

A change within the Air Force has shifted management responsibilities within the logistics community. Formerly diverse functions have come under the purview of a single manager-the Logistics Group Commander-who has inherited information systems that may riot be able to provide consolidated information for informed and accurate decision making. The purpose of this thesis was to describe the current and potential ability for three logistics information management systems to share data: Standard Base Supply System, Consolidated Aircraft Management System, and On-Line Vehicle Information Management System. A systems model was synthesized from the literature review to determine what components of a system …


Integrated Diagnostic Expert System Model (Idesm): A Model For The Conversion Of Fault Isolation Procedures Into An Integrated Diagnostic Expert System, Robert J. Lacey, Glen D. Steemson Dec 1992

Integrated Diagnostic Expert System Model (Idesm): A Model For The Conversion Of Fault Isolation Procedures Into An Integrated Diagnostic Expert System, Robert J. Lacey, Glen D. Steemson

Theses and Dissertations

The purpose of this research was to develop a model to convert existing hardcopy maintenance manual fault isolation procedures into electronic format and to partially automate the fault isolation process. A comprehensive model was developed which comprised four major components: user interface, expert system submodel, hypermedia submodel, and a submodel integration shell. Using this model, the F 15E nose landing gear fault isolation procedures were transformed into a rule based expert system. An existing hypermedia information base was expanded and subsequently integrated with the expert system to form the prototype application. The prototype was evaluated by engineering and maintenance personnel …


Domain Analysis Within The Gensif Framework, Heiko Thimm Oct 1992

Domain Analysis Within The Gensif Framework, Heiko Thimm

Theses

The GenSIF framework which is targeted towards very large, distributed, and complex software systems recently has been proposed to accomplish a form of systems engineering and systems development in which the issue of systems integration is considered from the beginning on.

One of the components of GenSIF is domain analysis. Domain analysis leads to the design of a domain model. The specific needs GenSIF has in that area were investigated with an emphasis on domain modeling. Main points addressed in that investigation were the issue regarding the relevant information for the domain modeling process and the required type of domain …


Abduction In Annotated Logic Programming, Krishnaprasad Thirunarayan Oct 1992

Abduction In Annotated Logic Programming, Krishnaprasad Thirunarayan

Kno.e.sis Publications

The author investigates techniques to make the logic programming paradigm more expressive for knowledge representation, while simultaneously retaining the computational advantages of efficiency and simplicity. He extends the annotated language of K. Thirunarayan and K. Kifer (1989) in various directions to obtain an enriched representation language. In particular, rule bodies are permitted to be a conjunction of literals, and the rules to be recursive. A class of annotated logic programs called the stratified programs is identified which can be given a unique supported minimal Herbrand model as their meaning. Abductive reasoning is integrated into this annotated logic framework. The notion …


A Set Of Orthogonal Polynomials Induced By A Given Orthogonal Polynomial, Walter Gautschi, Shikang Li Oct 1992

A Set Of Orthogonal Polynomials Induced By A Given Orthogonal Polynomial, Walter Gautschi, Shikang Li

Department of Computer Science Technical Reports

No abstract provided.


The Management Of Replicated Data, Hsueh-Chi Shih, C. Y. Ho, S. Alptekin Sep 1992

The Management Of Replicated Data, Hsueh-Chi Shih, C. Y. Ho, S. Alptekin

Computer Science Technical Reports

Data replication, which has the benefits of improving system availability and read performance, proved to be indispensable to many database applications. In a replicated database, the one-copy serializability of transaction executions can be ensured by employing a replica control mechanism on top of the traditional concurrency control mechanism. This work contains two replica control algorithms and a read-only transaction processing algorithm. Both replica control algorithms handle multiple site, communication and partitioning failures. The replica control algorithms achieve read operation efficiency by always translating a logical read operation into one local physical read operation and by taking advantage of the locality …


An Object-Oriented Approach To Data Exchange Applications: Development Of A Class Library For The Spatial Data Transfer Standard, Phyllis Altheida, John Prater Sep 1992

An Object-Oriented Approach To Data Exchange Applications: Development Of A Class Library For The Spatial Data Transfer Standard, Phyllis Altheida, John Prater

Computer Science Technical Reports

The object-orienced paradigm embodies a set of concepts that differentiates it from process-oriented and data-oriented methods. Among che commonly included principles are object, class, encapsulation, inheritance and polymorphism. The synergism of the concepts creates a powerful and new perspective that can be applied to all phases of systems development. Application developers need to try out the object-oriented languages, methodologies and development tools to help define its niche. The problem domain of data transfer standards is used to test the applicability of object-oriented techniques. Data transfer standards have three levels of abstraction: conceptual, logical, and format. The Spatial Data Transfer Standard …


Comparative Evaluation Of A Monocular Head Mounted Display Device Versus A Flat Screen Display Device In Presenting Aircraft Maintenance Technical Data, Jeffrey A. Friend, Randy S. Grinstead Sep 1992

Comparative Evaluation Of A Monocular Head Mounted Display Device Versus A Flat Screen Display Device In Presenting Aircraft Maintenance Technical Data, Jeffrey A. Friend, Randy S. Grinstead

Theses and Dissertations

As military developers provide increasingly complex weapon system, it becomes more difficult for maintenance technicians to perform their jobs. One aspect of the technicians' world is the need to access technical information in the performance of their duties. This study investigated two electronic display systems to evaluate which enhanced technician performance more. A Head Mounted Display (HMD) device and a portable hand-held flat-screen computer were evaluated in the performance of two flightline maintenance activities. Although both display systems were fully portable and self contained, only the HMD system allowed continuous access to technical information during task performance. In most cases, …


Using Flexible Transactions To Support Multisystem Telecommunication Applications, Mansoor Ansari, Linda Ness, Marek Rusinkiewicz, Amit P. Sheth Aug 1992

Using Flexible Transactions To Support Multisystem Telecommunication Applications, Mansoor Ansari, Linda Ness, Marek Rusinkiewicz, Amit P. Sheth

Kno.e.sis Publications

Service order provisioning is an important telecommunication application that automates the process of providing telephone services in response to the customer requests. It is an example of a multi-system application that requires access to multiple, independently developed application systems and their databases. In this paper, we describe the design and implementation of a prototype system1 that supports the execution of the Flexible Transactions and its use to develop the service order provisioning application. We argue that such approach may be used to support the development of multi-system, flow-through processing applications in a systematic and organized manner. Its advantages include fast …


Remote Memory Backing Storage For Distributed Virtual Memory Operating Systems (Thesis), James Griffoen Aug 1992

Remote Memory Backing Storage For Distributed Virtual Memory Operating Systems (Thesis), James Griffoen

Department of Computer Science Technical Reports

No abstract provided.


Observing Reusable Password Choices, Eugene H. Spafford Jul 1992

Observing Reusable Password Choices, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


Ccis Networking - July 1992, Nova University Jul 1992

Ccis Networking - July 1992, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.


Algorithms For Structural Schema Integration, James Geller, Ashish Mehra, Yehoshua Perl, Erich Neuhold, Amit P. Sheth Jun 1992

Algorithms For Structural Schema Integration, James Geller, Ashish Mehra, Yehoshua Perl, Erich Neuhold, Amit P. Sheth

Kno.e.sis Publications

Current view and schema integration methodologies are driven by semantic considerations, and allow integration of objects only if that is valid from semantic and structural viewpoints. We had introduced a new integration technique called structural integration. It permits integration of objects that have structural similarities, even if they differ semantically. This technique uses the object-oriented Dual Model which separates the representation of structure and semantics.

In this paper we introduce algorithms for structural integration. We apply these algorithms to integrate two views of a large university database schema which had significant structural similarities but differed semantically.


Sequential And Parallel Discrete Event Simulation On Computer Communication Networks, Tao Zhou Jun 1992

Sequential And Parallel Discrete Event Simulation On Computer Communication Networks, Tao Zhou

Masters Theses

This thesis presents the discrete event simulation technique on the network design, focusing on the methodology, modeling and implementation. The developed technique is suitable for the analysis of any store-and-forward computer communication networks with any level of complexity. The proposed generic simulation model can be used to test the architectures and protocols of existing networks and networks being designed. In implementation of the sequential discrete event simulation, an object-oriented programming strategy is applied to the network simulation using the C++ language. The parallel discrete event simulation is introduced to solve the problem of long time execution of the sequential simulation …


Future Research Directions In Problem Solving Environments For Computational Science, Stratis Gallopoulos, Elias N. Houstis, John R. Rice May 1992

Future Research Directions In Problem Solving Environments For Computational Science, Stratis Gallopoulos, Elias N. Houstis, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.


Computer Science Education At Wku, Malcolm Stallings May 1992

Computer Science Education At Wku, Malcolm Stallings

Mahurin Honors College Capstone Experience/Thesis Projects

No abstract provided.


Network Key Management In A Large Distributed Environment, J. J. Stapleton, D. C. St. Clair May 1992

Network Key Management In A Large Distributed Environment, J. J. Stapleton, D. C. St. Clair

Computer Science Technical Reports

The technique of using encryption for protecting information in a network environment involves managing encryption keys within that same network. In large distributed networks the goal of achieving a secure environment requires a secure method of performing network key management. Network security, system security, and application security by means of data encryption rely on encryption keys remaining secret.

Both international and domestic standards organizations such as the International Organization for Standardization (ISO), the American National Standards Institute (ANSI), and the National Institute of Standards and Technology (NIST) address the issues of encryption through various standards. However, these standards discuss methods …


Monitoring Computer Systems: An Intelligent Approach, Myron Zhihong Xu Apr 1992

Monitoring Computer Systems: An Intelligent Approach, Myron Zhihong Xu

Computer Science Theses & Dissertations

Monitoring modern computer systems is increasingly difficult due to their peculiar characteristics. To cope with this situation, the dissertation develops an approach to intelligent monitoring. The resulting model consists of three major designs: representing targets, controlling data collection, and autonomously refining monitoring performance. The model explores a more declarative object-oriented model by introducing virtual objects to dynamically compose abstract representations, while it treats conventional hard-wired hierarchies and predefined object classes as primitive structures. Taking the representational framework as a reasoning bed, the design for controlling mechanisms adopts default reasoning backed up with ordered constraints, so that the amount of data …


Reservable Transactions: An Approach For Reliable Multidatabase Transaction Management, Ahmed K. Elmagarmid, Jin Jing, James G. Mullen, Jamshid Sharif-Askary Feb 1992

Reservable Transactions: An Approach For Reliable Multidatabase Transaction Management, Ahmed K. Elmagarmid, Jin Jing, James G. Mullen, Jamshid Sharif-Askary

Department of Computer Science Technical Reports

No abstract provided.


Software Forensics: Can We Track Code To Its Authors?, Eugene H. Spafford, Stephen A. Weeber Feb 1992

Software Forensics: Can We Track Code To Its Authors?, Eugene H. Spafford, Stephen A. Weeber

Department of Computer Science Technical Reports

No abstract provided.


Multiswitch Hardware Configuration, Douglas E. Comer, Victor Norman Feb 1992

Multiswitch Hardware Configuration, Douglas E. Comer, Victor Norman

Department of Computer Science Technical Reports

No abstract provided.


Fractal (Reconstructive Analogue) Memory, David J. Stucki, Jordan B. Pollack Jan 1992

Fractal (Reconstructive Analogue) Memory, David J. Stucki, Jordan B. Pollack

Mathematics Faculty Scholarship

This paper proposes a new approach to mental imagery that has the potential for resolving an old debate. We show that the methods by which fractals emerge from dynamical systems provide a natural computational framework for the relationship between the “deep” representations of long-term visual memory and the “surface” representations of the visual array, a distinction which was proposed by (Kosslyn, 1980). The concept of an iterated function system (IFS) as a highly compressed representation for a complex topological set of points in a metric space (Barnsley, 1988) is embedded in a connectionist model for mental imagery tasks. Two advantages …


A Prototype Document Image Analysis System For Technical Journals, George Nagy, Sharad C. Seth, Mahesh Viswanathan Jan 1992

A Prototype Document Image Analysis System For Technical Journals, George Nagy, Sharad C. Seth, Mahesh Viswanathan

School of Computing: Faculty Publications

Intelligent document segmentation can bring electronic browsing within the reach of most users. The authors show how this is achieved through document processing, analysis, and parsing the graphic sentence.


Executing Multidatabase Transactions, Mansoor Ansari, Marek Rusinkiewicz, Linda Ness, Amit P. Sheth Jan 1992

Executing Multidatabase Transactions, Mansoor Ansari, Marek Rusinkiewicz, Linda Ness, Amit P. Sheth

Kno.e.sis Publications

In a multidatabase environment, the traditional transaction model has been found to be too restrictive. Therefore, several extended transaction models have been proposed in which some of the requirements of transaction, such as isolation or atomicity, are optional. The authors describe one of such extensions, the flexible transaction model and discuss the scheduling of transactions involving multiple autonomous database systems managed by heterogeneous DBMS.

The scheduling algorithm for flexible transactions is implemented using L.0, a logically parallel language which provides a framework for concisely specifying the multidatabase transactions and for scheduling them. The key aspects of a flexible transaction specification, …