Digital Commons Network^™

Test 1769: Agco Lt70 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Test 1769: Agco Allis 8745 Diesel (Cummins Engine), Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

Midcourse Guidance Law With Neural Networks, Dongchen Han, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A neural network-based synthesis of an optimal midcourse guidance law is presented in this study. We use a set of two-neural networks; the first network called 'a critic' outputs the Lagrange's multipliers arising in an optimal control formulation and second network called 'an action network' outputs the optimal guidance/control. In this so-called 'adaptive critic' approach, the inputs to the networks are the current values of the states. This approach needs no external training. System equations, optimality conditions and the costate equations are used in conjunction with the network outputs to provide the targets for the neural networks. When the critic …

Robust Adaptive Critic Based Neurocontrollers For Systems With Input Uncertainties, S. N. Balakrishnan, Zhongwu Huang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A two-neural network approach to solving optimal control problems is described in this study. This approach called the adaptive critic method consists of two neural networks: one is called the supervisor or critic, and the other is called an action network or controller. The inputs to both these networks are the current states of the system to be controlled. Each network is trained through an output of the other network and the conditions for optimal control. When their outputs are mutually consistent, the controller network output is optimal. The optimality is limited to the underlying model. Hence, we develop a …

The Relationships Between Student Diligence, Student Support Systems, Other Related Variables And Student Academic Outcomes In High Schools In Grenada, Christon Arthur

Dissertations

Problem. The Ministry of Education on the Caribbean Island of Grenada has been seeking to find ways to improve students' academic performance. The Ministry's emphasis has been on finding ways to make students more responsible for their education and at the same time trying to examine the level of educator support and parental support students receive. This emphasis on the level of educator and parental support that students receive was due in part to the findings of Hinds et al. (1999) that students in the Eastern Caribbean rate the support from parents and educators as being very important to …

Clear Consensus, Ambiguous Commitment, Christopher H. Schroeder

Faculty Scholarship

No abstract provided.

A Conversation About Equity, Claire L'Heureux-Dube

Denver Journal of International Law & Policy

No abstract provided.

Washington University Magazine And Alumni News, Spring 2000

Washington University Magazine

No abstract provided.

Washington University Magazine, Winter 2000

Washington University Magazine

No abstract provided.

View-Centric Reasoning About Parallel And Distributed Computation, Marc L. Smith

Retrospective Theses and Dissertations

The development of distributed applications has not progressed as rapidly as its enabling technologies. In part, this is due to the difficulty of reasoning about such complex systems. In contrast to sequential systems, parallel systems give rise to parallel events, and the resulting uncertainty of the observed order of these events. Loosely coupled distributed systems complicate this even further by introducing the element of multiple imperfect observers of these parallel events. The goal of this dissertation is to advance parallel and distributed systems development by producing a parameterized model that can be instantiated to reflect the computation and coordination properties …

The Effects Of The Lower Extremity Joint Motions On The Total Body Motion In Sit-To-Stand Movement, Bing Yu, Nicole Holly-Crichlow, Paul Brichta, Gordon R. Reeves, Cynthia M. Zablotny, Deborah A. Nawoczenski

Faculty Publications - College of Physical Therapy

Objective. The purpose of this study is to investigate the effects of lower extremity joint angular motions on the whole body linear motions in a sit-to-stand movement using a biomechanical model that describes the whole body linear velocity vector as functions of lower extremity joint angular velocities.

Design. Two-dimensional video analysis of whole body and joint kinematics.

Background. A biomechanical model that describes the whole body linear motions as functions of lower extremity joint angular motions is needed to provide clinically relevant information in clinical services and scientific research.

Methods. The linear velocity vector of the whole body motion during …

Trackless On-Line Paging And Computer Memory Management, Edward Benjamin Mikhalkov

UNLV Retrospective Theses & Dissertations

We consider existing research methodology for dealing with competitiveness analysis of on-line algorithms as well as introduce some newer analysis techniques for testing research hypotheses. Paging is discussed in general and current algorithms are surveyed and analyzed; We also present a new randomized on-line algorithm for the 2-page cache problem that matches the lower bound, and, therefore, is optimal. The algorithm uses fewer resources than currently known algorithms for the same problem, and is, therefore, an improvement on existing results. Experimental findings for this new algorithm are also presented and analyzed.

Parameterization And Sensitivity Analysis Of The Biome-Bgc Terrestrial Ecosystem Model: Net Primary Production Controls, Michael A. White, Peter Edmond Thornton, Steven W. Running, Ramakrishna R. Nemani

Numerical Terradynamic Simulation Group Publications

Ecosystem simulation models use descriptive input parameters to establish the physiology, biochemistry, structure, and allocation patterns of vegetation functional types, or biomes. For single-stand simulations it is possible to measure required data, but as spatial resolution increases, so too does data unavailability. Generalized biome parameterizations are then required. Undocumented parameter selection and unknown model sensitivity to parameter variation for larger-resolution simulations are currently the major limitations to global and regional modeling. The authors present documented input parameters for a process-based ecosystem simulation model, BIOME–BGC, for major natural temperate biomes. Parameter groups include the following: turnover and mortality; allocation; carbon to …

Staircase Band Gap Si 1-XGeX/Si Photodectectors, Zhiyun Lo, Ruolian Jiang, Youdou Zheng, Lan Zang, Zhizhong Chen, Shunming Zhu, Xuemei Cheng, Xiabing Liu

Physics Faculty Research and Scholarship

We fabricated Si _1-xGe_x/Si photodetectors by using a staircase band gap Si _1-xGe_x/Si structure. These devices exhibit a high optical response with a peak responsive wavelength at 0.96 μm and a responsivity of 27.8 A/W at -5 V bias. Excellent electrical characteristics evidenced by good diode rectification are also demonstrated. The dark current density is 0.1 pA/μm² at V bias, and the breakdown voltage is -27 V. The high response is explained as the result of a staircase band gap by theoretical analysis.

Spontaneous Evolution Of Rydberg Atoms Into An Ultracold Plasma, M. P. Robinson, B. Laburthe Tolra, Michael W. Noel, T. F. Gallagher, P. Pillet

Physics Faculty Research and Scholarship

We have observed the spontaneous evolution of a dense sample of Rydberg atoms into an ultracold plasma, in spite of the fact that each of the atoms may initially be bound by up to 100 cm21. When the atoms are initially bound by 70 cm21, this evolution occurs when most of the atoms are translationally cold, ,1 mK, but a small fraction, 􏰟1%, is at room temperature. Ionizing collisions between hot and cold Rydberg atoms and blackbody photoionization produce an essentially stationary cloud of cold ions, which traps electrons produced later. The trapped electrons rapidly collisionally ionize the remaining cold …

Security In Distributed Systems - A Framework For Different Application Types, Ingo Stengel

Theses

Security is a factor which decides upon the applicability of distributed applications. Therefore this thesis deals with security in distributed systems. The complexity of the existing distributed technologies makes it necessary to reduce the number of distributed technologies considered in this thesis, i.e. concentrating on: Java, Mobile Agents and CORBA, where only Java-based mobile agents will be considered.

After a short review of basic security principles including firewalls, existing security problems in the above mentioned distributed technologies are analysed. Additional generic problems in distributed systems are outlined.

Solutions are referring to two different areas: those regarding security problems with firewalls …

Employment Discrimination, Stewart J. Schwab

Cornell Law Faculty Publications

This article first parses the multiple overlapping definitions of discrimination, including distinctions between group and individual discrimination and between segregation and discrimination in pay. The article then summarizes the major economic models of discrimination, particularly Becker’s taste-for-discrimination model and statistical-discrimination models, as well as sorting the status-production models. The discussion focuses on the conditions under which markets will tend to eliminate discrimination, noting that this occurs in a more limited range of situations than commonly recognized. The article next surveys the economic role of anti-discrimination laws, evaluating arguments that the law speeds the journey to a non-discriminatory equilibrium and that …

A Policy Makers Guide To International Achievement Studies, Margaret Forster

Policy maker's guides

This guide provides policy makers with research-based information about international achievement studies. Good decision making at all levels of an education system is facilitated by easily accessible, relevant, and reliable information. Many indicators provide useful input to educational decision making; but the most important indicators are those which address the central concern of education: the promotion of student learning. Education systems monitor student learning—with the fundamental intention of promoting learning—by collecting, analysing and reporting student achievement data. Given that state, national and international achievement studies are both time consuming and expensive, it seems prudent to reflect on this effort: What …

Inbreeding In Law School Hiring: Assessing The Performance Of Faculty Hired From Within, Theodore Eisenberg, Martin T. Wells

Cornell Law Faculty Publications

This study compares the scholarly impact of inbred entry-level law school faculty members with the scholarly impact of noninbred entry-level law school faculty members. The sample includes 32 law schools and approximately 700 entry-level faculty members. By our measure of performance, scholarly impact as measured by citation frequency, inbred entry-level law school faculty members do not perform as well as noninbred entry-level faculty members.

Evaluation Of Hybridization Kinetics For Biosensor Applications Utilizing Single And Dual Fractal Analysis, Sunita Vontel

Electronic Theses and Dissertations

No abstract provided.

Elucidation Of The Mechanisms Of Heterogeneous Reburning Through Parameter And Kinetic Studies / By Lin Tang, Lin Tang

Electronic Theses and Dissertations

No abstract provided.

Developing Students' Understanding Of Similar Figures: A Perceptual Approach., Danny Ray Mcnabb

LSU Historical Dissertations and Theses

Children encounter and recognize similar figures in their everyday experiences with such things as basketballs, soccer balls, tennis balls, ping-pong balls; or a candy bar that comes in various sizes of the same shape. Yet their school experience with the mathematics of similarity generally does not build on these perceptual intuitions. Traditional mathematics curricula bypass students' visual intuitions and their quantitative understandings, proceeding directly to set piece problems solved by formal algebraic methods. The result for many students is that the topic of similarity contributes to their evolving view of mathematics as a domain of complex procedural methods divorced from …

Models Of Professional Development For Teachers: Factors Influencing Technology Implementation In Elementary Schools., Marilyn Hill Catchings

LSU Historical Dissertations and Theses

This qualitative multiple case study explored factors which contribute to the implementation of technology in elementary schools. This research had a phenomenological focus because there was a concentration on the structure and essence of the experiences of the teachers and leaders in the phenomenon, the implementation of technology in the school. The four schools chosen for the study were judged to have outstanding technology implementation by state technology leaders and a researcher screening process. They were selected because the researcher determined that these cases were the ones from which the most could be learned. These particular schools had ample technology …

Sociomathematical Norms Of Elementary School Classrooms: Crossnational Perspectives On The *Reform Of Mathematics Teaching., Jeongsuk Pang

LSU Historical Dissertations and Theses

Mathematics education reform in the United States has marshaled large-scale support for instructional innovation, and enlisted the participation and allegiance of large numbers of mathematics teachers. However, there is concern that many teachers have not grasped the full implications of the reform ideals. This study explored the breakdown that may occur between teachers' adoption of reform objectives and their successful incorporation of reform ideals by comparing and contrasting two reform-oriented classrooms. This study was an exploratory, qualitative, comparative case study using constant comparative analysis. Seven mathematics lessons were video-taped from each class, and intensive interviews conducted with the two teachers. …

A Longitudinal Study Of Students Academic Achievement Change: A Multilevel Structural Equation Model From A Multiple Group Perspective., John Kipngeno Rugutt

LSU Historical Dissertations and Theses

The focus of this study was three-fold: First, to determine if the growth parameters (intercepts and slopes) in mathematics and language were related within domains and ethnicity. Second, to determine if the pattern of interrelationships among the individual achievement growth parameters were the same for African American and White students. Third, to establish whether there existed discernible patterns variability in academic growth parameters within each ethnicity over time. The study employed a three-wave longitudinal panel design, with data drawn from Louisiana State Department of Education. The data were then analyzed utilizing both a multilevel structural equation methodology and hierarchical linear …

Water Quality Model For Evaluation Of Nonpoint Source Impacts Of Rice Field Runoff., Elizabeth Deette Smythe

LSU Historical Dissertations and Theses

Water quality impairment in many water bodies in the state of Louisiana is attributed to agricultural nonpoint sources of pollution. Many of these use-impaired streams have also been hydromodified to facilitate agricultural development, deepening and straightening the channels to form "stretch lakes". This dissertation evaluated the unique, and previously uncharacterized and unquantified ricefield loadings and their impacts on these dystrophic waterbodies in order to provide the Louisiana Department of Environmental Quality (LDEQ) with assessments of stream impacts from implementing altered cropping practices known as "best management practices" (BMPs). In order to produce an assessment of rice BMPs, this dissertation developed …

Response Of Granular Layers In Flexible Pavements Subjected To Aircraft Loads., Donald Mark Smith

LSU Historical Dissertations and Theses

Airfield pavement design is a complex blend of relatively simple linear elastic theory, fatigue concepts, correlations with small and full-scale tests, and pragmatic adjustments to reflect observations of in-service pavements. The granular base and subbase have always posed the most difficult analytical problem in traditional pavement design methodologies. For this reason, the granular layers have never been treated explicitly in design as have the asphalt concrete (AC) layer and subgrade layer, which have used predictive models for cracking in the AC and rutting in the subgrade as a function of linear-elastic strain and material properties. Instead, these granular layers were …

Performance Assessment And English Skill., Zhenghe Zhang

LSU Historical Dissertations and Theses

Recent developments in the philosophy of validity, highlighting the importance of investigating the consequences of assessment use, provide theoretical support for the move toward performance assessment. Numerous issues related to the choice of assessment approach (e.g., multiple-choice or performance-based) are not well understood today. This study investigated the potential interaction between assessment approach and the English skill of the examinee and the similarity of the information provided by multiple-choice and essay writing tests. Four hypotheses were examined in this study. Hypothesis 1 results indicated that students who were native speakers of English (regular students) achieved higher scores on the writing …

Domestic Labor And The Earnings Of Professionals., Rebecca Sue Carter

LSU Historical Dissertations and Theses

This dissertation focuses on how time allocated to domestic responsibilities affects the earnings of professionals. Although the earnings gap between women and men has narrowed, women are paid less than their male counterparts and a substantial part of the gender earnings gap remains unexplained. Women's growing entry into the full-time labor force has created new challenges for working women and dual-earner families. Professionals may manage domestic responsibilities differently than non professionals because they are likely to have jobs that offer higher pay and more autonomy. With fewer domestic demands placed on these households, we would expect to observe more gender …

A Behavior Analytic Approach To Developing Mathematics Skills In Second Graders: A Precision Teaching Intervention., Bruce Pierce Mortenson

LSU Historical Dissertations and Theses

This study examined the relative effects of two rates of responding on student endurance, accuracy and retention of basic math skills. Three cohorts, each consisting of four students, participated in the study and received training on two separate math skills. One skill was trained to a rate of responding consistent with a fluency standard and the other skill was trained to a rate of responding consistent with accurate but not fluent performance. The main finding underscored by the present study is that successful learning is enhanced if precipitated by fluent rates of responding. The data presented in each cohort demonstrated …