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2004

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The Development Of Plasmodium Falciparum In Experimentally Infected Anopheles Gambiae (Diptera: Culicidae) Under Ambient Microhabitat Temperature In Western Kenya, Bernard A. Okech, Louis C. Gouagna, Elizabeth Walczak, Ephantus W. Kabiru, John C. Beier, Guiyun Yan, John I. Githure Oct 2004

The Development Of Plasmodium Falciparum In Experimentally Infected Anopheles Gambiae (Diptera: Culicidae) Under Ambient Microhabitat Temperature In Western Kenya, Bernard A. Okech, Louis C. Gouagna, Elizabeth Walczak, Ephantus W. Kabiru, John C. Beier, Guiyun Yan, John I. Githure

All Peer-Reviewed Publications

The effect of microhabitat temperature variation on the early development of Plasmodium falciparum in experimentally infected Anopheles gambiae s.s. (Diptera: Culicidae) was studied. Batches of mosquitoes were fed artificially on gametocyteamic blood obtained from human volunteers and then held in five environmental conditions described as: (1) incubator maintained at constant temperature of 28 ± 1°C as control; (2) temperature unregulated laboratory environment; (3) screen house; (4) grass thatched mud house and (5) corrugated iron roofed mud house. Both the grass and iron roofed mud houses were real houses found in the village communities around the ICIPE Research Centre in Mbita …


Constructing A Coincident Index Of Business Cycles Without Assuming A One-Factor Model, Roberto S. Mariano, Yasutomo Murasawa Oct 2004

Constructing A Coincident Index Of Business Cycles Without Assuming A One-Factor Model, Roberto S. Mariano, Yasutomo Murasawa

Research Collection School Of Economics

The Stock-Watson coincident index and its subsequent extensions assume a static linear one-factor structure for the component indicators. Such assumption is restrictive in practice, however, with as few as four indicators. In fact, such assumption is unnecessary if one defines a coincident index as an estimate of latent monthly real GDP. This paper considers VAR and factor models for latent monthly real GDP and other coincident indicators, and estimates the models using the observable mixed-frequency series. For US data, Schwartz’s Bayesian information criterion selects a two-factor model. The smoothed estimate of latent monthly real GDP is the proposed index.


Effects Of Track Irregularities On Dynamic Responses Of A Moving Maglev Train, Aravind M. Hanasoge Oct 2004

Effects Of Track Irregularities On Dynamic Responses Of A Moving Maglev Train, Aravind M. Hanasoge

Mechanical & Aerospace Engineering Theses & Dissertations

The Maglev project at Old Dominion University is a collaboration between Old Dominion, American Maglev Technology (AMT), Lockheed Martin, other industry participants and the federal and state governments. This project began at the Norfolk campus in 2002. Under this project, researchers are aiming for a demonstrable engineering prototype that will operate smoothly at speeds of 40 - 45 miles per hour along the 3400 feet long track.

During testing, the vehicle is found to vibrate violently when operated on the ground. Furthermore, the vehicle failed to levitate when operated on the elevated track. As part of the investigation to determine …


Swing-Up And Balancing Nonlinear Control For A Rotational Inverted Pendulum, Jiang Wang Oct 2004

Swing-Up And Balancing Nonlinear Control For A Rotational Inverted Pendulum, Jiang Wang

Mechanical & Aerospace Engineering Theses & Dissertations

In this thesis, nonlinear controllers are designed for the swing-up and balance modes of a rotational inverted pendulum, which is a pendulum hinged on a horizontally rotating link. The proposed control algorithms are designed by partial feedback linearization and sliding mode control techniques, for swing-up and balancing respectively. First a mathematical model of the pendulum dynamics is derived, followed by experimental verification. Then the system model is partially linearized, which makes it possible for the system to track a simple desired trajectory with "pump energy" function. Then a swing-up controller is designed. For an under-actuated mechanical system, like the inverted …


Application Of Queuing Theory And Procedure Time Estimation In A Local Healthcare System, Galina Tsoy Oct 2004

Application Of Queuing Theory And Procedure Time Estimation In A Local Healthcare System, Galina Tsoy

Engineering Management & Systems Engineering Theses & Dissertations

People in the United States pay more for their basic healthcare needs than do people in any other nation in the world. When we consider that the United States is the wealthiest nation in the world, controlling the majority of the world's resources, it seems only reasonable to ask: Why should it be this way?

In an effort to address this problem, this thesis examines two possible methods of improving health care efficiency in hospitals. The thesis is thus in two parts: the first part examines resource allocation in medical units using Queuing Theory, and the second part examines a …


A Profile Of Students Enrolled At The University Of Northern Iowa, Fall Semester 2004, University Of Northern Iowa Oct 2004

A Profile Of Students Enrolled At The University Of Northern Iowa, Fall Semester 2004, University Of Northern Iowa

Institutional Effectiveness & Planning Documents

Contents:

--- Preface
--- At a Glance
--- Profile Summary
--- Section I: Total Student Enrollment for Fall Semester 2004
--- Section II: New Students Entering UNI Fall Semester 2004
--- Section III: Miscellaneous


Indexing And Matching Of Polyphonic Songs For Query-By-Singing System, Tat-Wan Leung, Chong-Wah Ngo Oct 2004

Indexing And Matching Of Polyphonic Songs For Query-By-Singing System, Tat-Wan Leung, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

This paper investigates the issues in polyphonic popular song retrieval. The problems that we consider include singing voice extraction, melodic curve representation, and database indexing. Initially, polyphonic songs are decomposed into singing voices and instruments sounds in both time and frequency domains based on SVM and ICA. The extracted singing voices are represented as two melodic curves that model the statistical mean and neighborhood similarity of notes. To speed up the matching between songs and query, we further adopt proportional transportation distance to index the songs as vantage point trees. Encouraging results have been obtained through experiments.


Deformable Object Model Matching By Topological And Geometric Similarity, Kwok-Leung Tan, Rynson W. H. Lau, Chong-Wah Ngo Oct 2004

Deformable Object Model Matching By Topological And Geometric Similarity, Kwok-Leung Tan, Rynson W. H. Lau, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

In this paper, we present a novel method for efficient 3D model comparison. The method is designed to match highly deformed models through capturing two types of information. First, we propose a feature point extraction algorithm, which is based on “Level Set Diagram”, to reliably capture the topological points of a general 3D model. These topological points represent the skeletal structure of the model. Second, we also capture both spatial and curvature information, which describes the global surface of a 3D model. This is different from traditional topological 3D matching methods that use only low-dimension local features. Our method can …


Blocking Reduction Strategies In Hierarchical Text Classification, Ee Peng Lim, Aixin Sun, Wee-Keong Ng, Jaideep Srivastava Oct 2004

Blocking Reduction Strategies In Hierarchical Text Classification, Ee Peng Lim, Aixin Sun, Wee-Keong Ng, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

One common approach in hierarchical text classification involves associating classifiers with nodes in the category tree and classifying text documents in a top-down manner. Classification methods using this top-down approach can scale well and cope with changes to the category trees. However, all these methods suffer from blocking which refers to documents wrongly rejected by the classifiers at higher-levels and cannot be passed to the classifiers at lower-levels. We propose a classifier-centric performance measure known as blocking factor to determine the extent of the blocking. Three methods are proposed to address the blocking problem, namely, threshold reduction, restricted voting, and …


Compliant Encryption Of Jpeg2000 Codestreams, Yongdong Wu, Robert H. Deng Oct 2004

Compliant Encryption Of Jpeg2000 Codestreams, Yongdong Wu, Robert H. Deng

Research Collection School Of Computing and Information Systems

This paper presents a compliant encryption method for JPEG 2000 codestreams such that the encryption process does not introduce superfluous JPEG2000 markers in the protected codestream, i.e., the protected codestream preserves the syntax of the original codestream. The proposed encryption method works with any standard ciphers, incurs no storage overhead, introduces negligible computational cost and maintains all the desirable properties of the original JPEG 2000 codestream such as error resilience and scalability.


Flexible Verification Of Mpeg-4 Stream In Peer-To-Peer Cdn, Tieyan Li, Yongdong Wu, Di Ma, Robert H. Deng Oct 2004

Flexible Verification Of Mpeg-4 Stream In Peer-To-Peer Cdn, Tieyan Li, Yongdong Wu, Di Ma, Robert H. Deng

Research Collection School Of Computing and Information Systems

The current packet based stream authentication schemes provide effective and efficient authentication over a group of packets transmitted on erasure channels. However, by fixing the packets in transmission, any packet manipulation will cause authentication failure. In p2p content delivery network where a proxy-in-the-middle is able to store, forward, transcode and transform the stream, previous schemes are simply unapplicable. To address the problem, we propose a flexible verification scheme that relies on special stream formats (i.e. Unequal Loss Protection ULP scheme [7]). We apply the so called Unequal Loss Verification ULV scheme into MPEG-4 framework. The encoding, packing, amortizing and verifying …


Trust Establishment In Large Scale Grid Settings, Bo Zhu, Tieyan Li, Huafei Zhu, Mohan S . Kankanhalli, Feng Bao, Robert H. Deng Oct 2004

Trust Establishment In Large Scale Grid Settings, Bo Zhu, Tieyan Li, Huafei Zhu, Mohan S . Kankanhalli, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Trust establishment is hard in grid architecture by the ad hoc nature. To set up trust in large scale of network is more difficult. In this paper, we propose an automatic key management (AKM) model and corresponding key construction schemes. The hierarchical structure is formed automatically and scale seamlessly in arbitrary network sized. Regions are configured differently according to various levels of risks faced. The novel model provides an integrated solution for self-organized trust establishment, upon which rich appliances are securely supported. It is automatic, flexible, and scalable. Furthermore, simulation results show that computation costs due to the variations are …


Design And Analysis Of A Cooperative Medium Access Scheme For Wireless Mesh Networks, Arup Acharya, Archan Misra, Sorav Bansal Oct 2004

Design And Analysis Of A Cooperative Medium Access Scheme For Wireless Mesh Networks, Arup Acharya, Archan Misra, Sorav Bansal

Research Collection School Of Computing and Information Systems

This paper presents the detailed design and performance analysis of MACA-P, a RTS/CTS based MAC protocol, that enables simultaneous transmissions in wireless mesh networks. The IEEE 802.11 DCF MAC prohibits any parallel transmission in the neighborhood of either a sender or a receiver (of an ongoing transmission). MACA-P is a set of enhancements to the 802.11 MAC that allows parallel transmissions in situations when two neighboring nodes are either both receivers or transmitters, but a receiver and a transmitter are not neighbors. The performance of MACA-P in terms of system throughput is obtained through a simulation of the protocol using …


Faculty Tenure Report, Fall 2004, University Of Northern Iowa. Office Of Information Management And Analysis. Oct 2004

Faculty Tenure Report, Fall 2004, University Of Northern Iowa. Office Of Information Management And Analysis.

Institutional Effectiveness & Planning Documents

Statistical report showing the number of faculty that are tenured, on the tenure track, or not on the tenure track, broken down by college, department, gender, minority status, and if full or part time.


On The Nonparametric Identification Of Nonlinear Simultaneous Equations Models: Comment On B. Brown (1983) And Roehrig (1988), C. Lanier Benkard, Steven T. Berry Oct 2004

On The Nonparametric Identification Of Nonlinear Simultaneous Equations Models: Comment On B. Brown (1983) And Roehrig (1988), C. Lanier Benkard, Steven T. Berry

Cowles Foundation Discussion Papers

This note revisits the identification theorems of B. Brown (1983) and Roehrig (1988). We describe an error in the proofs of the main identification theorems in these papers, and provide an important counterexample to the theorems on the identification of the reduced form. Specifically, contrary to the theorems, the reduced form of a nonseparable simultaneous equations model is not identified even under the assumptions of those papers. We conclude the note with a conjecture that it may be possible to use classical exclusion restrictions to recover some of the key implications of the theorems.


Empirical Similarity, Itzhak Gilboa, Offer Lieberman, David Schmeidler Oct 2004

Empirical Similarity, Itzhak Gilboa, Offer Lieberman, David Schmeidler

Cowles Foundation Discussion Papers

An agent is asked to assess a real-valued variable Y p based on certain characteristics X p = ( X 1 p ,…, X m p ), and on a database consisting ( X 1 i ,…, X m i , Y i ) for i = 1,…, n . A possible approach to combine past observations of X and Y with the current values of X to generate an assessment of Y is similarity-weighted averaging. It suggests that the predicted value of Y , Y s p , be the weighted average of all previously observed values Y i …


Bacterial Degradation Of Disinfection By-Products In Drinking Water, Laura Inga Fauntleroy Oct 2004

Bacterial Degradation Of Disinfection By-Products In Drinking Water, Laura Inga Fauntleroy

Chemistry & Biochemistry Theses & Dissertations

Chlorine became a major disinfectant for the removal of microbial contaminants in 1914. Current water chlorination procedures yield halogenated disinfection byproducts (DBPs), such as haloalkanes and haloacetic acids (HAAs), due to the reaction of chlorine with naturally occurring organic compounds. Various water utilities have observed decreased HAAs levels in maximum residence time locations (MRTLs), where they were expected to be higher. These MRTLs have low free chlorine residual and high heterotrophic bacteria plate counts. Xanthobacter autotrophicus, GJ-10, is a bacterium that has been shown to contain dehalogenase enzymes and, therefore, can biodegrade HAAs. A number of water-system bacteria were …


Distal Placement Of An End-To-Side Bypass Graft Anastomosis A 3-D Computational Study, John Robert Di Cicco Oct 2004

Distal Placement Of An End-To-Side Bypass Graft Anastomosis A 3-D Computational Study, John Robert Di Cicco

Mechanical & Aerospace Engineering Theses & Dissertations

A three-dimensional computational fluid dynamics study of blood flow through stenotic arteries has been conducted. Flow phenomena, such as separation regions and turbulence, can be found distal to an arterial stenosis. Frequently, a bypass graft using an end-to-side technique is attached to a stenotic artery to restore adequate blood flow. However, a significant percentage of these grafts fail after thirty postoperative days due to intimal hyperplasia development around the distal anastomosis. Moreover, aberrant wall shear rates have been implicated as a factor in the development of intimal hyperplasia. Thus, the present study examines whether placement of the distal end of …


Hydrologic Variations Within Created And Natural Wetlands In Southeastern Virginia, Aaron Dyer Despres Oct 2004

Hydrologic Variations Within Created And Natural Wetlands In Southeastern Virginia, Aaron Dyer Despres

OES Theses and Dissertations

The hydrology of wetlands, particularly how wetland soils collect, store, and redistribute water strongly affects how wetland systems function. In created wetlands, construction processes and materials influence the hydrology and consequently, the potential for successful reestablishment of target vegetation communities. During .2002- 2004, the Virginia Department of Transportation constructed large mitigation wetlands on two different Quaternary aged surfaces with very similar hydrogeomorphic conditions. The Sandy Bottom Nature Park site (SBNP) located in Hampton, VA and rests on the sandy loam Tabb Formation while the Charles City Wetland site (CCW) lies on the older and clay-rich Shirley Formation. This study documents …


Effects Of Initial Seated Position On Whiplash In Low Speed Rear-End Impacts Comparison And Study Using The Tno Rear Impact Dummy (Trid) Model, Manjunath P. Venkataramana Oct 2004

Effects Of Initial Seated Position On Whiplash In Low Speed Rear-End Impacts Comparison And Study Using The Tno Rear Impact Dummy (Trid) Model, Manjunath P. Venkataramana

Mechanical & Aerospace Engineering Theses & Dissertations

Despite numerous investigations devoted to its scrutiny, injury causing mechanism associated with rear-end impact collision producing injury such as Whiplash Associated Disorder (WAD) has remained a mystery. Several criteria have been proposed to predict the injury causing mechanism, but none have been universally accepted. The challenge lies in determining a set of testing procedures representative of real-world collisions, wherein the results obtained are not only the same as human testing, but remain consistent with various subjects and impact conditions. It is hypothesized that one of the most important considerations is the effect of initial seated position (ISP).

This thesis can …


Vector Operations In Superscalar Architectures, Nathan Daniel Flinn Oct 2004

Vector Operations In Superscalar Architectures, Nathan Daniel Flinn

Electrical & Computer Engineering Theses & Dissertations

Vector calculations are very prevalent today. Though the vector-processing computer is quite an old concept, superscalar processors lack hardware support for vector operations. This thesis investigates whether an ordinary superscalar computer architecture can be designed to include hardware support for improved vector operations without drastically changing the existing superscalar design and behavior. A computer architecture design was created and implemented that included the vector multiply (dot product) operation. The design includes a Vector Operations Unit that captures incoming vector operations and generates the necessary set of machine instructions to complete the vector operation internally. It then delivers these instructions to …


Modeling And Simulation Of Photonic Crystal Fibers Using Finite Difference Frequency Domain Method, Md. Khalid Ikram Oct 2004

Modeling And Simulation Of Photonic Crystal Fibers Using Finite Difference Frequency Domain Method, Md. Khalid Ikram

Electrical & Computer Engineering Theses & Dissertations

Photonic crystal fibers (PCFs) allow guiding light in low-index core. These fibers exhibit properties such as single-mode operation in broad wavelength region. The mode shape and group velocity dispersion can be controlled by designing the microstructures of the cladding. In order to study these properties, a fast, efficient, and highly accurate numerical modeling method is required.

A full-vectorial finite-difference frequency-domain (FDFD) method is implemented. The modal properties of conventional step index fiber and index-guiding PCF are analyzed using this modeling technique. Compared to plane wave expansion and biorthogonal basis methods, FDFD is found to be simple, reliable, and efficient. PCFs …


Bottleneck Analysis Of Cports, Sreekalyana Chakravarthy Kajuluri Oct 2004

Bottleneck Analysis Of Cports, Sreekalyana Chakravarthy Kajuluri

Electrical & Computer Engineering Theses & Dissertations

CPortS is a transportation logistics simulation that models the flow of military cargo through a seaport and the interaction of the cargo with the port resources and infrastructure. It provides information about the seaport's capabilities, how the cargo has been handled, how many days the cargo took to clear a particular port area, and the overall throughput of the seaport. The model is highly data intensive since it models the huge traffic in a real seaport.

Bottlenecks reduce system performance. Systems that are traffic intensive or simulations of systems, which are data intensive, encounter bottlenecks, which reduce their performance. In …


Hierarchical Hybrid Multicast An End System Multicast Algorithm Approach, Guillermo Loaisiga Oct 2004

Hierarchical Hybrid Multicast An End System Multicast Algorithm Approach, Guillermo Loaisiga

Electrical & Computer Engineering Theses & Dissertations

Due to the rapid development in the computer and communication technologies, the Internet is experiencing an increasing demand of high-speed, real-time distributed applications, such as live streaming multimedia, videoconferencing, distributed simulations, and multiparty games. Multicast is an efficient transmission mechanism to support these applications. Historically, IP Multicast (IPM) has provided multicast support with well-known benefits, especially in bandwidth savings. However, it has experienced little deployment due to economic and architectural limitations.

Overlay multicast holds promise for the implementation of large scale Internet multicast services. An overlay network is a virtual topology constructed on top of the Internet infrastructure. This concept …


Huffman Approach To Opcode Compression, Jason B. Shreve Oct 2004

Huffman Approach To Opcode Compression, Jason B. Shreve

Electrical & Computer Engineering Theses & Dissertations

Instructions are the building blocks of computer programs. They are composed of opcodes, which uniquely identify each instruction, and the operands or data. In most architectures, the instruction length is a set multiple of the word size. The size and number of operands vary by instruction. Due to programmer usage, program need, or compiler design, opcodes do not occur with a constant distribution. Likely, some opcodes occur very frequently, whereas others occur very infrequently or not at all. If the length of an opcode were representative of its frequency, compression in program size might be achieved.

This thesis is an …


An Algorithm For Locating Fundamental Frequency (F0) Markers In Speech, Princy Dikshit Oct 2004

An Algorithm For Locating Fundamental Frequency (F0) Markers In Speech, Princy Dikshit

Electrical & Computer Engineering Theses & Dissertations

Speech has been the principal form of human communication since it began to evolve at least one hundred thousand years ago. Speech is produced by vibrations of the vocal cords. The rate of vibration of the cords is called fundamental frequency (F0) or pitch. The objective of this thesis is to locate pitch period cycles on a cycle-by-cycle basis. The complexity in identifying pitch cycles stems from the highly irregular nature of human speech. Dynamic programming is used to combine two sources of information for pitch period marking. One source of information is the "local" information corresponding to the location …


Michael Martin And Ricki Monnier, Eds., The Impossibility Of God, Frank B. Dilley Oct 2004

Michael Martin And Ricki Monnier, Eds., The Impossibility Of God, Frank B. Dilley

Faith and Philosophy: Journal of the Society of Christian Philosophers

No abstract provided.


Just Behind The Mountain: Refugee Children Imagine Tibet, Emma Tobin Oct 2004

Just Behind The Mountain: Refugee Children Imagine Tibet, Emma Tobin

Independent Study Project (ISP) Collection

Since the Tibetan diaspora began in 1959, when His Holiness the 14th Dalai Lama fled Tibet for India, many Tibetans have settled and started families in exile. Today, a large percentage of Tibetan refugees have been born in exile, and have therefore never seen their country. Within Tibetan exile communities, however, the importance of Tibetan identity is strongly emphasized and people are still very much invested in the plight of Tibet. As a result, there exist strong ideas about the reality of life in Tibet within the exile community. According Jamyang Norbu, “Though the Shangri-la stereotype is a Western creation, …


Environmental Sustainability And The Traditional Tibetan Home, Katherine Shrader Oct 2004

Environmental Sustainability And The Traditional Tibetan Home, Katherine Shrader

Independent Study Project (ISP) Collection

In Tibetan Buddhism, the srivatsa, or glorious endless knot, reminds one of the truth of reality. Six right-angled, intertwined strands flow endlessly together, each one connected to the other, each one giving form to the next. So flows reality. Looking past the illusion of isolation, the endless knot illustrates the interdependence and mutual cooperation that runs the world.

No event, no living being has the ability to stand by itself, completely unaffected and unaffecting. All phenomena are intertwined. Every human action, however big or small, impacts the world in some way. The endless knot unveils the truth of reality so …


Gaming Delaware, William Wilson Bratton Oct 2004

Gaming Delaware, William Wilson Bratton

Articles

No abstract provided.