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Pc–Based Data Acquisition For A Solid Substrate Cultivation Deep Bed Reactor, Mari S. Chinn, Sue E. Nokes, Richard S. Gates Mar 2003

Pc–Based Data Acquisition For A Solid Substrate Cultivation Deep Bed Reactor, Mari S. Chinn, Sue E. Nokes, Richard S. Gates

Biosystems and Agricultural Engineering Faculty Publications

This work describes an instrumentation and data acquisition system designed for a deep bed reactor used to cultivate Trichoderma longibrachiatum on wheat bran. The system allowed on–line measurements of substrate temperature, oxygen concentration within the reactor headspace, relative humidity and temperature of the inlet air, and inlet airflow rates while maintaining aseptic conditions and without disturbing the cultivation process. An error analysis for the instrumentation and data acquisition equipment was completed and provided insight into the reliability of the sensor readings. The collected data provided quantitative information about the reactor system dynamics which can be used to evaluate and apply …

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Motion Analysis And Segmentation Through Spatio-Temporal Slices Processing, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang Mar 2003

Motion Analysis And Segmentation Through Spatio-Temporal Slices Processing, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang

Research Collection School Of Computing and Information Systems

This paper presents new approaches in characterizing and segmenting the content of video. These approaches are developed based upon the pattern analysis of spatio-temporal slices. While traditional approaches to motion sequence analysis tend to formulate computational methodologies on two or three adjacent frames, spatio-temporal slices provide rich visual patterns along a larger temporal scale. In this paper, we first describe a motion computation method based on a structure tensor formulation. This method encodes visual patterns of spatio-temporal slices in a tensor histogram, on one hand, characterizing the temporal changes of motion over time, on the other hand, describing the motion …

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Energy-Efficient Broadcast And Multicast Trees For Reliable Wireless Communication, Suman Banerjee, Archan Misra, Jihwang Yeo, Ashok Agrawala Mar 2003

Energy-Efficient Broadcast And Multicast Trees For Reliable Wireless Communication, Suman Banerjee, Archan Misra, Jihwang Yeo, Ashok Agrawala

Research Collection School Of Computing and Information Systems

We define energy-efficient broadband and multicast schemes for reliable communication in multi-hop wireless networks. Unlike previous techniques, the choice of neighbors in the broadband and multicast trees in these schemes, are based not only on the link distance, but also on the error rates associated with the link. Our schemes can be implemented using both positive and negative acknowledgement based reliable broadcast techniques in the link layer. Through simulations, we show that our scheme achieves up to 45% improvement over previous schemes on realistic 100-node network topologies. A positive acknowledgment based implementation is preferred. Our simulations show that the additional …

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Explicit Building-Block Multiobjective Genetic Algorithms: Theory, Analysis, And Developing, Jesse B. Zydallis Mar 2003

Explicit Building-Block Multiobjective Genetic Algorithms: Theory, Analysis, And Developing, Jesse B. Zydallis

Theses and Dissertations

This dissertation research emphasizes explicit Building Block (BB) based MO EAs performance and detailed symbolic representation. An explicit BB-based MOEA for solving constrained and real-world MOPs is developed the Multiobjective Messy Genetic Algorithm II (MOMGA-II) which is designed to validate symbolic BB concepts. The MOMGA-II demonstrates that explicit BB-based MOEAs provide insight into solving difficult MOPs that is generally not realized through the use of implicit BB-based MOEA approaches. This insight is necessary to increase the effectiveness of all MOEA approaches. In order to increase MOEA computational efficiency parallelization of MOEAs is addressed. Communications between processors in a parallel MOEA …

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Inquisitive Pattern Recognition, Amy L. Magnus Mar 2003

Inquisitive Pattern Recognition, Amy L. Magnus

Theses and Dissertations

The Department of Defense and the Department of the Air Force have funded automatic target recognition for several decades with varied success. The foundation of automatic target recognition is based upon pattern recognition. In this work, we present new pattern recognition concepts specifically in the area of classification and propose new techniques that will allow one to determine when a classifier is being arrogant. Clearly arrogance in classification is an undesirable attribute. A human is being arrogant when their expressed conviction in a decision overstates their actual experience in making similar decisions. Likewise given an input feature vector, we say …

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A Three-Dimensional Heads-Up Primary Navigation Reference Display For Paratroopers Performing High Altitude High Open Jumps, Brian A. Balazs Mar 2003

A Three-Dimensional Heads-Up Primary Navigation Reference Display For Paratroopers Performing High Altitude High Open Jumps, Brian A. Balazs

Theses and Dissertations

The Department of Defense (DoD) relies on the para-dropping of resources to meet different objectives in order to accomplish missions during peace-time, war-time, or military operations other than war. The resources dropped to the ground via parachute range from supplies and equipment to the most valued asset, people. Tactics have been developed to increase the safety of troops parachuting into areas of conflict. These tactics include high-altitude high-opening (HAHO) jumping and night jumping. HAHO jumping allows paratroopers to travel large distances in the air away from the path of the delivering aircraft. While night jumping, done with the aid of …

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Searching System Call Information For Clues: The Effects Of Intrusions Of Processes, Mark G. Reith Mar 2003

Searching System Call Information For Clues: The Effects Of Intrusions Of Processes, Mark G. Reith

Theses and Dissertations

The United States Air Force extensively uses information systems as a tool managing and maintaining its information. The increased dependence on these systems in recent years has necessitated the need for protection front threats of information warfare and cyber terrorism. One type of protection utilizes intrusion detection systems to provide indications that intrusive behavior has occurred. Other types of protection may include packet filtering, cryptography and strong user authentication. Traditional approaches toward intrusion detection rely on features that are external to computer processes. By treating processes as black-boxes, intrusion detection systems may miss a wealth of information that could be …

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Performance Evaluation And Analysis Of Effective Range And Data Throughput For Unmodified Bluetooth Communication Devices, Timothy F. Kneeland Mar 2003

Performance Evaluation And Analysis Of Effective Range And Data Throughput For Unmodified Bluetooth Communication Devices, Timothy F. Kneeland

Theses and Dissertations

The DoD and the Air Force continually seek to incorporate new technology in an effort to improve communication, work effectiveness, and efficiency. Office devices utilizing Bluetooth technology simplify device configuration and communication. They provide a means to communicate wirelessly over short distances thereby eliminating the need for different vendor specific cables and interfaces. One of the key concerns involved in incorporating new communication technology is security; the fundamental security concern of wireless communication is interception. Studies focusing on IEEE 802.11b have shown vulnerability zones around many DoD installations that reflect the ranges at which wireless communications using the 802.11b standard …

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Adjusting Sensing Range To Maximize Throughput On Ad-Hoc Multi-Hop Wireless Networks, Christopher K. Roberts Mar 2003

Adjusting Sensing Range To Maximize Throughput On Ad-Hoc Multi-Hop Wireless Networks, Christopher K. Roberts

Theses and Dissertations

The use of ad-hoc wireless networks is becoming common within the United States Air Force. Such networks are able to be implemented where traditional wired networks are either impractical or too expensive. As the miniaturization of communication devices continues, it is becoming increasingly common for mobile devices to communicate directly with each other, eliminating the need for center access points. Such a network is referred to as a multi-hop ad-hoc network, or simply a multi-hop network. Most multi-hop network protocols use some form of carrier sensing to determine if the wireless channel is in use. A large sensing range can …

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Creating And Modifying Dynamic Animation Sequences Using The Tgt_Toolkit, Ross Gore Mar 2003

Creating And Modifying Dynamic Animation Sequences Using The Tgt_Toolkit, Ross Gore

Department of Math & Statistics Technical Report Series

Creating and modifying the dynamic animation sequences within the TGT_Toolkit is not for the faint of heart. This report contains advice, guidelines and refers to an example of how I went about constructing the dynamic animation sequences within the Linked Lists Tutorial. I have identified three major areas of that seem to be common to all dynamic animation sequences, but distinct from simply extending TGT_Slide as most other slides do; these areas are: dynamically creating animation configurations, providing "undo" and slide saving functionality and sequencing saved slides once they are properly configured. In these areas "slide saving" and "saved slides" …

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Self-Configuring Clusters, Data Aggregation And Authentication In Microsensor Networks, Maleq Khan, Bharat Bhargava, Leszek Lilien Mar 2003

Self-Configuring Clusters, Data Aggregation And Authentication In Microsensor Networks, Maleq Khan, Bharat Bhargava, Leszek Lilien

Department of Computer Science Technical Reports

No abstract provided.

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Dynamic Trust Production Based On Based On Interaction Sequence, Yuhui Zhong, Yi Lu, Bharat Bhargava Mar 2003

Dynamic Trust Production Based On Based On Interaction Sequence, Yuhui Zhong, Yi Lu, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.

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Protection Of Application Service Hosting Platforms: An Operating System Perspective, Xuxian Jiang, Dongyan Xu Mar 2003

Protection Of Application Service Hosting Platforms: An Operating System Perspective, Xuxian Jiang, Dongyan Xu

Department of Computer Science Technical Reports

No abstract provided.

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Using Sequence Analysis To Perform Application-Based Anomaly Detection Within An Artificial Immune System Framework, Larissa A. O'Brien Mar 2003

Using Sequence Analysis To Perform Application-Based Anomaly Detection Within An Artificial Immune System Framework, Larissa A. O'Brien

Theses and Dissertations

The Air Force and other Department of Defense (DoD) computer systems typically rely on traditional signature-based network IDSs to detect various types of attempted or successful attacks. Signature-based methods are limited to detecting known attacks or similar variants; anomaly-based systems, by contrast, alert on behaviors previously unseen. The development of an effective anomaly-detecting, application based IDS would increase the Air Force's ability to ward off attacks that are not detected by signature-based network IDSs, thus strengthening the layered defenses necessary to acquire and maintain safe, secure communication capability. This system follows the Artificial Immune System (AIS) framework, which relies on …

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Stegfs: A Steganographic File System, Hwee Hwa Pang, Kian-Lee Tan, Xuan Zhou Mar 2003

Stegfs: A Steganographic File System, Hwee Hwa Pang, Kian-Lee Tan, Xuan Zhou

Research Collection School Of Computing and Information Systems

While user access control and encryption can protect valuable data from passive observers, those techniques leave visible ciphertexts that are likely to alert an active adversary to the existence of the data, who can then compel an authorized user to disclose it. This paper introduces StegFS, a steganographic file system that aims to overcome that weakness by offering plausible deniability to owners of protected files. StegFS securely hides user-selected files in a file system so that, without the corresponding access keys, an attacker would not be able to deduce their existence, even if the attacker is thoroughly familiar with the …

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Health Care Informatics, Keng Siau Mar 2003

Health Care Informatics, Keng Siau

Research Collection School Of Computing and Information Systems

The health care industry is currently experiencing a fundamental change. Health care organizations are reorganizing their processes to reduce costs, be more competitive, and provide better and more personalized customer care. This new business strategy requires health care organizations to implement new technologies, such as Internet applications, enterprise systems, and mobile technologies in order to achieve their desired business changes. This article offers a conceptual model for implementing new information systems, integrating internal data, and linking suppliers and patients.

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Adaptive Transmission Power For Optimal Energy Reliable Multi-Hop Wireless Communication, Suman Banerjee, Archan Misra Mar 2003

Adaptive Transmission Power For Optimal Energy Reliable Multi-Hop Wireless Communication, Suman Banerjee, Archan Misra

Research Collection School Of Computing and Information Systems

We define a transmission power adaptation-based routing technique that finds optimal paths for minimum energy reliable data transfer in multi-hop wireless networks. This optimal choice of the transmission power depends on the link distance between the two nodes and the channel characteristics. Typical energy efficient routing techniques use a transmission power such that the received signal power at the destination minimally exceeds a desired threshold signal strength level. In this paper we argue that such a choice of the transmission power does not always lead to optimal energy routes, since it does not consider differences in the receiver noise levels. …

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Hierarchical Text Classification Methods And Their Specification, Ee Peng Lim, Aixin Sun, Wee-Keong Ng Mar 2003

Hierarchical Text Classification Methods And Their Specification, Ee Peng Lim, Aixin Sun, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

Hierarchical text classification refers to assigning text documents to the categories in a given category tree based on their content. With large number of categories organized as a tree, hierarchical text classification helps users to find information more quickly and accurately. Nevertheless, hierarchical text classification methods in the past have often been constructed in a proprietary manner. The construction steps often involve human efforts and are not completely automated. In this chapter, we therefore propose a specification language known as HCL (Hierarchical Classification Language). HCL is designed to describe a hierarchical classification method including the definition of a category tree …

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Deterministic Intracellular Modeling, Jacqueline B. Young Mar 2003

Deterministic Intracellular Modeling, Jacqueline B. Young

Theses and Dissertations

The United States Air Force is interested in the potential side effects at the cellular level from exposure to mission-essential chemicals. Presently, Air Force toxicology studies are conducted to help shed light in identifying potential hazards to workers. However, it takes a considerable amount of money, resources, and time to obtain and analyze experimental results from toxicology studies. The necessity for innovative methods that enable researchers to more effectively generate and analyze data is apparent.

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Implementing An Information Retrieval And Visualization Framework For Heterogeneous Data Types, Andrew J. Kowalchuk Mar 2003

Implementing An Information Retrieval And Visualization Framework For Heterogeneous Data Types, Andrew J. Kowalchuk

Theses and Dissertations

In today's information focused world, there is no lack of entities focused on information gathering. However, there is still a widespread epidemic of information starvation in the Department of Defense (DoD). This starvation is attributed to the lack of interoperability between information gatherers and information consumers. To alleviate this problem, the DoD has put forth a vision of a Joint Battlespace Infosphere (JBI). This research proposes a framework for sharing and finding resources in a JBI. The framework uses an extensible metadata specification, agent technology, and the Control of Agent Based Systems (CoABS). It provides several tools for publication and …

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Antecedents And Outcomes Of End User Computing Competence, David A. Case Mar 2003

Antecedents And Outcomes Of End User Computing Competence, David A. Case

Theses and Dissertations

The tremendous proliferation of end user computing (EUC) in the workplace over the past few decades is cause for concern in public and private organizations. Computer use has moved from individuals working with "dumb" terminals in centralized networks to individuals operating personal computers, just as powerful as yesterday's mainframe. The end user has had to evolve and will continue evolving as well; from someone with low level technical skills to someone with a high level of technical knowledge and information managerial skills. Because EUC continues growing more sophisticated, end users must not only maintain a level of competence, but prepare …

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Comparing The Routing Energy Overheads Of Ad-Hoc Routing Protocols, Sorav Bansal, Rajeev Shorey, Archan Misra Mar 2003

Comparing The Routing Energy Overheads Of Ad-Hoc Routing Protocols, Sorav Bansal, Rajeev Shorey, Archan Misra

Research Collection School Of Computing and Information Systems

We use simulations to study the comparative routing overheads of three ad-hoc routing protocols, namely AODV, DSDV and DSR. In contrast to earlier studies, we focus exclusively on the energy consumption and not on other metrics such as the number of routing packets. In particular, we study the `range effects' of the three protocols, i.e., how changes to the transmission power and transmission radius affect the overall energy consumed by routing-related packets. Due to the broadcast nature of the wireless medium, the energy spent in packet receptions is almost as important as the transmission power; using the number of transmissions …

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Maca-P: A Mac For Concurrent Transmissions In Multi-Hop Wireless Networks, Arup Acharya, Archan Misra, Sorav Bansal Mar 2003

Maca-P: A Mac For Concurrent Transmissions In Multi-Hop Wireless Networks, Arup Acharya, Archan Misra, Sorav Bansal

Research Collection School Of Computing and Information Systems

This paper presents the initial design and performance study of MACA-P, a RTS/CTS based MAC protocol that enables simultaneous transmissions in multihop ad-hoc wireless networks. Providing such low-cost multihop and high performance wireless access networks is an important enabler of pervasive computing. MACA-P is a set of enhancements to the 802.11 DCF that allows parallel transmissions in many situations when two neighboring nodes are either both receivers or both transmitters, but a receiver and a transmitter are not neighbors. Like 802.11, MACA-P contains a contention-based reservation phase prior to data transmission. However, the data transmission is delayed by a control …

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A Visual Language For Composable Simulation Scenarios, Carolyn R. Bartley Mar 2003

A Visual Language For Composable Simulation Scenarios, Carolyn R. Bartley

Theses and Dissertations

Modeling and Simulation plays an important role in how the Air Force trains and fights, Scenarios are used in simulation to give users the ability to specify entities and behaviors that should be simulated by a model: however, building and understanding scenarios can be a difficult and time-consuming process, furthermore, as composable simulations become more prominent, the need for a common descriptor for simulation scenarios has become evident. In order to reduce the complexity of creating and understanding simulation scenarios, a visual language was created, The research on visual languages presented in this thesis examines methods of visually specifying the …

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Reverse Geographic Location Of A Computer Node, Clinton G. Carr Iii Mar 2003

Reverse Geographic Location Of A Computer Node, Clinton G. Carr Iii

Theses and Dissertations

The determination of methods by which a user is able to locate his computer when that user does not know his current location, termed "homestation", will provide the Air Force an advantage over its adversaries. The methods are a combination of different mathematical techniques that enable the user to manipulate data to minimize the effects of delay caused by various factors on the network. The techniques use the smallest round trip time obtained from the ping utility. This time is then converted into miles and plotted on a map of the United States. The methods used to solve this problem …

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Distributed Control Of A Swarm Of Autonomous Unmanned Aerial Vehicles, James T. Lotspeich Mar 2003

Distributed Control Of A Swarm Of Autonomous Unmanned Aerial Vehicles, James T. Lotspeich

Theses and Dissertations

With the increasing use of Unmanned Aerial Vehicles (UAV)s military operations, there is a growing need to develop new methods of control and navigation for these vehicles. This investigation proposes the use of an adaptive swarming algorithm that utilizes local state information to influence the overall behavior of each individual agent in the swarm based upon the agent's current position in the battlespace. In order to investigate the ability of this algorithm to control UAVs in a cooperative manner, a swarm architecture is developed that allows for on-line modification of basic rules. Adaptation is achieved by using a set of …

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Uml Assisted Visual Debugging For Distributed Systems, Benjamin R. Musial Mar 2003

Uml Assisted Visual Debugging For Distributed Systems, Benjamin R. Musial

Theses and Dissertations

The DOD is developing a Joint Battlespace Infosphere, linking a large number of data sources and user applications. To assist in this process, debugging and analysis tools are required. Software debugging is an extremely difficult cognitive process requiring comprehension of the overall application behavior, along with detailed understanding of specific application components. This is further complicated with distributed systems by the addition of other programs, their large size and synchronization issues. Typical debuggers provide inadequate support for this process, focusing primarily on the details accessible through source code. To overcome this deficiency, this research links the dynamic program execution state …

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An Artificial Immune System Strategy For Robust Chemical Spectra Classification Via Distributed Heterogeneous Sensors, Mark A. Esslinger Mar 2003

An Artificial Immune System Strategy For Robust Chemical Spectra Classification Via Distributed Heterogeneous Sensors, Mark A. Esslinger

Theses and Dissertations

The timely detection and classification of chemical and biological agents in a wartime environment is a critical component of force protection in hostile areas. Moreover, the possibility of toxic agent use in heavily populated civilian areas has risen dramatically in recent months. This thesis effort proposes a strategy for identifying such agents vis distributed sensors in an Artificial Immune System (AIS) network. The system may be used to complement "electronic" nose ("E-nose") research being conducted in part by the Air Force Research Laboratory Sensors Directorate. In addition, the proposed strategy may facilitate fulfillment of a recent mandate by the President …

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The Generalizability Of Private Sector Research On Software Project Management In Two Usaf Organizations: An Exploratory Study, Michael R. Garman Mar 2003

The Generalizability Of Private Sector Research On Software Project Management In Two Usaf Organizations: An Exploratory Study, Michael R. Garman

Theses and Dissertations

Project managers typically set three success criteria for their projects: meet specifications, be on time, and be on budget. However, software projects frequently fail to meet these criteria. Software engineers, acquisition officers, and project managers have all studied this issue and made recommendations for achieving success. But most of this research in peer reviewed journals has focused on the private sector. Researchers have also identified software acquisitions as one of the major differences between the private sector and public sector MIS. This indicates that the elements for a successful software project in the public sector may be different from the …

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The Effect Of Interactivity And Instructional Exposure On Learning Effectiveness And Knowledge Retention: A Comparative Study Of Two U.S. Air Force Computer-Based Training (Cbt) Courses For Network User Licensing, Matthew J. Imperial Mar 2003

The Effect Of Interactivity And Instructional Exposure On Learning Effectiveness And Knowledge Retention: A Comparative Study Of Two U.S. Air Force Computer-Based Training (Cbt) Courses For Network User Licensing, Matthew J. Imperial

Theses and Dissertations

The United States Air Force (USAF) currently employs the use of computer-based training (CET) across a host of requirements. One such requirement is in the Information Assurance (IA) arena and involves the training/licensing of over one-million computer network end-users. USAF use of CETs has been shown to possess a potential for substantial fiscal savings. However, studies investigating the learning outcomes of learning effectiveness (initial learning) and knowledge retention (sustained learning) associated with USAF CETs are lacking.

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