Physical Sciences and Mathematics Commons^™

Effects Of Atmospheric Turbulence On The Propagation Of Flattened Gaussian Optical Beams, Doris Cowan

Electronic Theses and Dissertations

In an attempt to mitigate the effects of the atmosphere on the coherence of an optical (laser) beam, interest has recently been shown in changing the beam shape to determine if a different power distribution at the transmitter will reduce the effects of the random fluctuations in the refractive index. Here, a model is developed for the field of a flattened Gaussian beam as it propagates through atmospheric turbulence, and the resulting effects upon the scintillation of the beam and upon beam wander are determined. A comparison of these results is made with the like effects on a standard TEM00 …

High Birefringence And Low Viscosity Liquid Crystals, Chien-Hui Wen

Electronic Theses and Dissertations

In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism …

Test 1883: Agco Lt75a Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1873: John Deere 8430 16 Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1880: Mccormick Xtx 185/Mccormick Mtx 165 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1876: Challenger Mt 645b Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1878: Challenger Mt 665b Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1870: John Deere 5103 Diesel 9-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Test 1884: John Deere 8130 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Test 1885: John Deere 8230 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Test 1887: John Deere 8330 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Nebraska Summary 559: Massey Ferguson 5470 Dyna 4 Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …

Improving Channel Throughput Of Wlans And Ad Hoc Networks Using Explicit Denial Of Requests, Maggie Xiaoyan Cheng, Yadi Ma, Yi Wang

Computer Science Faculty Research & Creative Works

A new Multiple Access Control scheme for wireless ad hoc networks and WLANs is proposed. This scheme uses explicit denial of channel requests and a busy tone to improve channel throughput. Performance analysis shows significant improvement when the network is under heavy traffic load.

The Antecedents Of M-Commerce Adoption, Morris Kalliny, Michael S. Minor

Business and Information Technology Faculty Research & Creative Works

The growth of Internet shopping has been attributed to rapid advances in technology and other influences such as convenience. We empirically investigate the relationship between demographics, ease of use, convenience, usefulness and enjoyment and intention to use m-commerce and attitude toward m-commerce. Two studies were conducted where a student and a non student sample was used. Data analysis revealed age, gender and educational level of customers do not play a role in influencing intention to use m-commerce. However, convenience, ease of use, usefulness and enjoyment all play a role in the customer's intention to use m-commerce.

Adapting User Interface To Expedite Physician Order Entry: A Frontline To Ensure Patient Safety, Chiang S. Jao, Daniel B. Hier

Chemistry Faculty Research & Creative Works

Preventable Medical Errors Are a Major Problem in Healthcare. Maintenance of Accurate Problem Lists and Drug Lists in the Electronic Medical Record is Critical to the Practice of Medicine and Patient Safety. We Built a Simulator of a Clinical Decision Support System that Automates the Process of Maintaining an Electronic Problem List by Processing Drug Order Requests from a Simulated Computerized Physician Order Entry System. Preliminary Results Revealed that the Productivity of the System Increased When the User Interface Was Improved. This Study Highlights the Importance of an Enhanced User Interface as a Frontline in Expediting Physician Data Entry, Streamlining …

Practical Experiences In Using Model-Driven Engineering To Develop Trustworthy Computing Systems, Thomas Weigert, Frank Weil

Computer Science Faculty Research & Creative Works

In this paper, we describe how Motorola has deployed model-driven engineering in product development, in particular for the development of trustworthy and highly reliable telecommunications systems, and outline the benefits obtained. Model-driven engineering has dramatically increased both the quality and the reliability of software developed in our organization, as well as the productivity of our software engineers. Our experience demonstrates that model-driven engineering significantly improves the development process for trustworthy computing systems.

Multimedia Correlation Analysis In Unstructured Peer-To-Peer Network, Bo Yang, A. R. Hurson, Yu Jiao, Thomas E. Potok

Computer Science Faculty Research & Creative Works

Recent years saw the rapid development of peer-topeer (P2P) networks in a great variety of applications. However, similarity-based k-nearest-neighbor retrieval (k-NN) is still a challenging task in P2P networks due to the multiple constraints such as the dynamic topologies and the unpredictable data updates. Caching is an attractive solution that reduces network traffic and hence could remedy the technological constraints of P2P networks. However, traditional caching techniques have some major shortcomings that make them unsuitable for similarity search, such as the lack of semantic locality representation and the rigidness of exact matching on data objects. To facilitate the efficient similarity …

A Hierarchical Secure Routing Protocol Against Black Hole Attacks In Sensor Networks, Jian Yin, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

A black hole attack is a severe attack that can be easily employed against routing in sensor networks. In a black hole attack, a malicious node spuriously announces a short route to the sink node (the destination) to attract additional traffic to the malicious node and then drops them. In this paper, we propose a hierarchical secure routing protocol for detecting and defending against black hole attacks. The proposed protocol uses only symmetric key cryptography to discover a safe route against black hole attacks. The comparison of the proposed protocol with two other existing approaches proves that the proposed scheme …

An Internet Based Intelligent Argumentation System For Collaborative Engineering Design, Xiaoqing Frank Liu, Samir Raorane, Man Zheng, Ming-Chuan Leu

Computer Science Faculty Research & Creative Works

Modern product design is a very complicated process which involves groups of designers, manufacturers, suppliers, and customer representatives. Conflicts are unavoidable in collaboration among multiple stakeholders, who have different objectives, requirements, and priorities. Unfortunately, current web-based collaborative engineering design systems do not support collaborative conflict resolution. In this paper, we will develop an intelligent computational argumentation model to enable management of a large scale argumentation network, and resolution of conflicts based on argumentation from many participants. A web-based intelligent argumentation tool is developed as a part of a web-based collaborative engineering design system based on the above model to resolve …

Cadre: A Collaborative Replica Allocation And Deallocation Approach For Mobile-P2p Networks, Anirban Mondal, Sanjay Kumar Madria, Masaru Kitsuregawa

Computer Science Faculty Research & Creative Works

This paper proposes CADRE (Collaborative Allocation and Deallocation of Replicas with Efficiency), a dynamic replication scheme for improving the typically low data availability in mobile ad-hoc peer-to-peer (M-P2P) networks. The main contributions of CADRE are two-fold. First, it collaboratively performs both replica allocation and deallocation in tandem to facilitate optimal replication and to avoid 'thrashing' conditions. Second, it addresses fair replica allocation across the MHs. CADRE deploys a hybrid super-peer architecture in which some of the MHs act as the 'gateway nodes' (GNs) in a given region. GNs facilitate both search and replication. Our performance study indicates that CADRE indeed …

Secrout: A Secure Routing Protocol For Sensor Networks, Jian Yin, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

In this paper, we present a secure routing protocol for sensor networks (SecRout) to safeguard sensor networks under different types of attacks. The SecRout protocol uses the symmetric cryptography to secure messages, and uses a small cache in sensor nodes to record the partial routing path (previous and next nodes) to the destination. It guarantees that the destination will be able to identify and discard the tampered messages and ensure that the messages received are not tampered. Comparing the performance with non-secure routing protocol AODV (ad hoc on demand distance vector routing), the SecRout protocol only has a small byte …

A Mathematical Formulation Of Dna Computation, Mingjun Zhang, Maggie Xiaoyan Cheng, Tzyh-Jong Tarn

Computer Science Faculty Research & Creative Works

DNA computation is to use DNA molecules for information storing and processing. The task is accomplished by encoding and interpreting DNA molecules in suspended solutions before and after the complementary binding reactions. DNA computation is attractive, due to its fast parallel information processing, remarkable energy efficiency, and high storing capacity. Challenges currently faced by DNA computation are (1) lack of theoretical computational models for applications, and (2) high error rate for implementation. This paper attempts to address these problems from mathematical modeling and genetic coding aspects. The first part of this paper presents a mathematical formulation of DNA computation. The …

Electrochemical Deposition And Characterization Of Fe₃O₄ Films Produced By The Reduction Of Fe(Iii)-Triethanolamine, Hiten M. Kothari, Elizabeth A. Kulp, Steven J. Limmer, Philippe Poizot, Eric W. Bohannan, Jay A. Switzer

Chemistry Faculty Research & Creative Works

In this paper, we demonstrate that films of magnetite, Fe₃O₄, can be deposited by the electrochemical reduction of a Fe(III)-triethanolamine complex in aqueous alkaline solution. the films were deposited with a columnar microstructure and a [100] preferred orientation on stainless steel substrates. In-plane electrical transport and magnetoresistance measurements were performed on the films after they were stripped off onto glass substrates. the resistance of the films was dependent on the oxygen partial pressure. We attribute the increase in resistance in O₂ and the decrease in resistance in Ar to the oxidation and reduction of grain …

A Comparative Study Of The Properties Of Polar And Nonpolar Solvent/Solute/Polystyrene Solutions In Microwave Fields Via Molecular Dynamics, Mark J. Purdue, Macduff O. Okuom, Frank D. Blum, James M. D. Macelroy, D. F. O'Shea

Chemistry Faculty Research & Creative Works

The influence of an applied microwave field on the dynamics of methylamine-dichloromethane (DCM) mixtures bound within atactic polystyrene (a-PS) over a range of polymer densities from 30 to 94 wt % polymer was examined using atomistic molecular dynamics simulations. This study is an extension of previous studies on methylamine transport in relatively polar polystyrene solutions of methanol and dimethylformamide [M. J. Purdue et al., J. Chem. Phys. 124, 204904 (2006)]. A direct comparison is made across the three types of polystyrene solutions. Consideration is given to both solvent and reagent transport within the polymer solutions under zero-field conditions and in …

Acid-Catalyzed Time-Efficient Synthesis Of Resorcinol-Formaldehyde Aerogels And Crosslinking With Isocyanates, Sudhir Mulik, Chariklia Sotiriou-Leventis, Nicholas Leventis

Chemistry Faculty Research & Creative Works

Aerogels are open-cell foams derived from supercritical fluid (SCF) drying of wet gels. Their large internal void space is responsible for low thermal conductivity, high surface area and high acoustic impedance. Most aerogels are based on inorganic metal or semimetal oxide frameworks. Pekala and co-workers synthesized resorcinol-formaldehyde (RF) organic aerogels by poly-condensation of resorcinol with formaldehyde in the presence of Na₂CO₃ as base catalyst, followed by drying with SCF CO₂. Low-density RF aerogels prepared by this method exhibit high porosities (>80%), high surface areas (400-900 m²g^-1), ultrafine cell-size (<500 > Å) …

Conformal Internal Coating Of Macroporous Co-Continuous Mcf-Silicas With Isocyanate Derived Polymers, Nicholas Leventis, Chariklia Sotiriou-Leventis, Xiaojiang Wang, Sudhir Mulik

Chemistry Faculty Research & Creative Works

Since their discovery in 1992,1,2 templating sol-gel silica with structuredirecting agents has resulted in new materials with ordered mesoporous (2-50 nm) structure that is investigated for application in areas as diverse as high surface area supports for caralysts or as nanostructured drug storage and release platforms.3 Structure-directing agents are typically surfactants ranging from cationic detergents such as alkyl-trimethylammonium salts with C8-C18 hydrocarbon chains to non-ionic tertiary amines, polyethylene oxide or amphiphilic triblock copolymers such as poly(ethyleneoxide)-blockpoly( propyleneoxide)-block-poly(ethyleneoxide) (e.g., Pluronic P123). Depending on the surfactant and the conditions (e.g., kind and concentration of catalyst) the structure of the mesopores may vary …

Segmental Dynamics In Poly(Methyl Acrylate) On Silica: Molecular-Mass Effects, Burak Metin, Frank D. Blum

Chemistry Faculty Research & Creative Works

The effect of molecular mass on the segmental dynamics of poly(methyl acrylate) (PMA) adsorbed on silica was studied using deuterium quadrupole-echo nuclear magnetic resonance (NMR) and modulated differential scanning calorimetry. Samples adsorbed on silica (all about 1.5 mg PMA/m2 silica) were shown to have more restricted segmental mobility, and higher Tg's, than the corresponding bulk PMA samples. Around the glass-transition region, adsorbed samples exhibited segmental mobility, which could be classified as heterogeneous due to a superposition of more-mobile and less-mobile components present in the deuterium NMR spectra. This heterogeneity was consistent with a motional gradient with more-mobile segments near the …

Effects Of Silvicultural Techniques And Landscape Management On Habitat Quality And Relative Abundance For Northern Bobwhites In A Pine Plantation Forest, Jason Douglas Burke

LSU Master's Theses

Pine plantation forests are increasing in scope across the southeastern United States, particularly Louisiana. These areas provide poor quality bobwhite brood-rearing habitats, and become increasingly degraded without periodic disturbance. Poor quality habitat conditions at a landscape-level scale usually results in reduced fall bobwhite body weights, creating low survival rates. We researched 4 understory vegetation management techniques (ie. mowing, no treatment, burn only, and imazapyr with burning) within pine plantations to evaluate their effects on vegetation composition and structure and on arthropod abundance and availability relative to bobwhite brooding habitat in 2002-2005. We used 1,155 human-imprinted bobwhite chicks to estimate foraging …

Water Resources Year In Review - Winter 2006, Vol. 19, No. 2, Annis Water Resource Institute

AWRI Reviews

No abstract provided.

Intrinsic Linking And Knotting Of Graphs In Arbitrary 3–Manifolds, Erica Flapan, Hugh Howards, Don Lawrence, Blake Mellor

Mathematics, Statistics and Data Science Faculty Works

We prove that a graph is intrinsically linked in an arbitrary 3–manifold MM if and only if it is intrinsically linked in S³. Also, assuming the Poincaré Conjecture, we prove that a graph is intrinsically knotted in M if and only if it is intrinsically knotted in S³.