Digital Commons Network^™

A Comparison Study Of Two Alternative Education Programs On Selected School-Related Attitudes, Rebecca Ann Albiston

UNLV Retrospective Theses & Dissertations

This study examined two alternative education programs designed to encourage at-risk students to remain in school. The purpose was to identify the ability of each program to change the school-related attitudes and orientations that may contribute to the student's dropping out of school (school and teacher bonding, academic self-concept, perception of opportunity, self-esteem); In addition to the five dependent variables measured, the number of credits earned as well as the holding power of the program, were examined and compared between the two groups as indication of educational engagement. The study was conducted as a comparison between the two programs and …

A Study To Determine How Businesses In The Area Known As Clark County, Nevada Perceive The Computer-Related Skills That High School Graduates Should Possess Upon Graduation, Lynda Ruth Yates Spann

UNLV Retrospective Theses & Dissertations

The purpose of the study was to identify (1) what business functions are being performed with computers in the local community of Clark County, Nevada, (2) those entry-level skills required under each of the three major computer applications of word processing, electronic spreadsheet, and data base, (3) the specific "Brand Name" of third party application software programs used in the local business community of Clark County, Nevada. (Abstract shortened with permission of author.).

A Data Structural Approach To The Problem Of Contour Plotting, Sivesh Pradhaan

UNLV Retrospective Theses & Dissertations

This paper describes the results of a research on the problem of contouring an estimated surface. It takes a data structural approach to the problem and also uses a special logic developed to make parallelism possible. This algorithm draws all the contour curves at the same time. The data structure used by this algorithm is described in detail here; Intersection points are connected by examining the orientation of the corresponding face used to represent that patch of the estimated surface. The total number of intersections with a contour plane in a cell and the presence of horizontal lines in a …

Computation In Director String Calculus, Vugranam Chakravarthy Sreedhar

UNLV Retrospective Theses & Dissertations

In this thesis we introduce a modified version of Director String Calculus (MDSC) which preserves the applicative structure of the original lambda terms and captures the strong reduction as opposed to weak reduction of the original Director String Calculus (DSC). Furthermore, our reduction system provides an environment which supports the nonatomic nature of substitution operation and hence can lend itself to parallel and optimal reduction. We shall compare our reduction method with other reduction methods, and discuss some of the advantages and disadvantages of our method.

Development Of A Test Facility For Making In-Duct Sound Measurements According To Astm E477-1984, David Arthur Wade

UNLV Retrospective Theses & Dissertations

Duct silencers must reduce sound levels enough to be noticed by the human ear. By placing the appropriate duct silencer in the air-conditioning duct system, sound levels in rooms where noise is a problem can be significantly reduced. Only through insertion loss measurements can the appropriate silencer be determined for the desired noise reduction; This thesis involves the modification and qualification of the reverberation chamber in the Multi-Function Lab at the University of Nevada, Las Vegas, for the purpose of creating a controlled sound testing environment. It also involves the design and construction of facilities for making insertion loss measurements. …

Sir Isaac's Duel (Original Play), Rand Walter Higbee

UNLV Retrospective Theses & Dissertations

The play Sir Isaac's Duel concentrates on Edmond Halley's discovery of the genius of Isaac Newton. Halley attempts to bring Newton's theories out to the public, Newton refuses, and the "duel" begins. Other characters in the play are as follows: Mary Halley, the wife of Edmond; Catherine Barton, Newton's niece; Jonathan Swift, who is in love with Catherine; and Gottfried Leibniz, who engaged with Newton in a priority debate over the invention of Calculus; This is a full-length play with an approximate running time of 95 minutes.

Effects Of Ambient Lake Mohave Temperatures On Development, Oxygen Consumption, And Hatching Success Of The Razorback Sucker, Michael A. Bozek, Larry J. Paulson, Gene R. Wilde

Publications (WR)

Spawning of razorback suckers, Xyrauchen texanus, in Lake Mohave occurred from 10-22° C and larvae were collected at water temperatures from 10-15° C in 1982 and 1983. In the laboratory, hatching success was similar from 12-20° C, but reduced hatching success was found at 10° C while none hatched at 8°C. Development rate and oxygen consumption were positively related to incubation temperature. Direct effects of ambient Lake Mohave water temperatures on hatching success of razorback sucker embryos are considered minimal. Historical spawning temperatures for the species are hypothesized based upon successful incubation temperatures and comparison to the white sucker, …

Introduction And Enhancement Of Vegetative Cover At Lake Mead, Jennifer S. Haley, Lisa K. Croft, Suzanne E. Leavitt, Larry J. Paulson

Publications (WR)

Studies done by the Nevada Department of Wildlife (NDOW) and the Arizona Fish and Game between 1978 and 1981 indicate that inadequate cover may be limiting the production and survival of largemouth bass at the Lake Mead National Recreation Area (LMNRA). As a result of these studies, NDOW initiated a contract in 1986 with the Lake Mead Research Center (LMRC) to investigate means of improving habitat for game fish by introducing natural and/or artificial cover. During Phase I (1986-1987) of this contract, the shoreline of Lake Mead was surveyed for aquatic and terrestrial plant growth. Also during this time, submerged …

Late-Holocene Earthflows Of The Willard Playa/Dune Complex, Estancia Valley, New Mexico: A Geomorphic Response To Climatic Change, Kurt A. Goebel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Late-middle to late Holocene dune sediment that overlies Pleistocene lacustrine sediment marks the onset of xeric conditions in the Estancia Valley, central New Mexico. Incised into the underlying lacustrine sediments, the modern deflation basins are enclosed by parabolic dunes composed of clay and gypsum derived from the underlying sediment.

Located on the in-facing dune slopes of the deflation basins, the most striking geomorphic feature of this dune complex are numerous elongated scars. These relict scars document a geomorphically distinct earthflow event. Arroyos that cut into flow scars expose eolian earthflow sediment overlying lacustrine deposits. In the zone of depletion, erosional-flow …

Temporal And Spatial Patterns Of Abundance Of Age 0 Threadfin Shad (Dorosoma Petenense) In Overton Arm, Lake Mead, William Lee Pelle

Publications (WR)

Temporal and spatial patterns of age 0 threadfin shad (Dorosoma petenense) abundance and growth, in the Overton Arm of Lake Mead, were examined to evaluate the effects of resource availability on the young fish. This was part of a larger, game fishery enhancement study (Lake Mead Fertilization Project), designed to assess feasability of increasing survivorship of larval/juvenile shad by boosting phosphate levels, thereby increasing algal and zooplankton biomass, during the shad spawning period. Shad are the primary forage base for the striped bass (Morone saxatilis) and black bass (Macropterus salmoides) fisheries. Weekly samples were …

The Geology And Structural Significance Of The Arch Mountain Area, Northern Black Mountains, Mohave County, Arizona, Edward Eschner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Arch Mountain area of northwestern Mohave County, Arizona, is typified by rocks that range from Precambrian to Quatemary in age. Arch mountain is a north-trending horst bounded on the west by the Petroglyph Wash graben and on the east by the Virgin Basin. A low-angle normal fault, herein named the Arch Mountain detachment fault, is exposed for 6 km along strike just below the ridge crest of Arch Mountain, and it is typified by a 2-20 cm thick zone of hematite-impregnated breccia and cataclasite. The detachment fault places an upper plate of Precambrian gneiss, Paleozoic quartzite, shale and dolomite, …

Total Maximum Daily Loads And Waste Load Allocations For Las Vegas Bay: Rationale And Calulations, State Of Nevada: Division Of Environmental Protection

Publications (WR)

In September 1987 the Nevada Division of Environmental Protection revised Water Quality Standards for Las Vegas Wash (LVW) and Lake Mead. Standards were set for chlorophyll-a and unionized ammonia in Las Vegas Bay (LVB) (NDEP 1987). The 1986 and 1987 LVB data showed non-achievement of both the chlorophyll-a and unionized ammonia standard which triggered an analysis of total phosphorus and total ammonia Total Maximum Daily Loads and Waste Load Allocations which are presented in this report. This report is separated into three sections: 1. 1987 Las Vegas Bay Water Quality Conditions and Seasonal Periodicity. 2. Concentration Estimates at Northshore Road …

Limnological Monitoring Data For Lake Mead During 1988, Suzanne E. Leavitt, Larry J. Paulson, State Of Nevada: Division Of Environmental Protection

Publications (WR)

Limnological monitoring was conducted in Las Vegas Bay and Boulder Basin from April to December of 1988. The purpose of the monitoring was to (i) document possible changes in water quality resulting from decreased phosphorus loading and increased ammonia in Las Vegas Wash, and (ii) establish a data base for evaluating the adequacy of water quality standards.

Red Swamp Crayfish Ecology In Lake Mead, Suzanne E. Leavitt, Jennifer Stephens Haley, Mikell Hager, Donald H. Baepler, Nevada Department Of Wildlife

Publications (WR)

Red swamp crayfish (Procambarus clarkii) were trapped in Flamingo Wash, an urban wash of Las Vegas, during four periods of 1988. Life history and reproductive success were determined. The trapped crayfish were marked and released into a study cove in Lake Mead as part of an experimental stocking program. Retrap data from the study cove were used to determine life history, habitat preferences, and movement patterns of the stocked crayfish. In addition, a literature search was done on red swamp crayfish ecology, including food preferences, life history, habitat preferences and fish predation.

Water Relations Of Obligate Riparian Plants As A Function Of Streamflow Diversion On The Bishop Creek Watershed, S. D. Smith, J. L. Nachlinger, A. B. Wellington, C. A. Fox

Life Sciences Faculty Research

We investigated the water relations of obli-gate riparian plants on paired diverted and undiverted reaches on Bishop Creek, Eastern Sierra Nevada. Ri-parian plants on diverted reaches had reduced stomatal conductance and water potential compared to plants on undiverted reaches in a dry year, but not in a high runoff year. Juvenile plants on diverted reaches had reduced stomatal conductance and lower midday water potentials relative to surrounding mature trees, a trend that was not observed on undiverted reaches. Plants on diverted reaches possessed significantly smaller, thicker leaves and a reduced total leaf area relative to trees on streamside reaches. Reduced …

Riparian Plant Water Relations Along The North Fork Of The Kings River, California, J. L. Nachlinger, S. D. Smith, R. J. Risser

Life Sciences Faculty Research

Plant water relations of five obligate ripar-ian species were studied along California's North Fork Kings River. Diurnal stomatal conductance, transpi-ration, and xylem pressure potentials were measured throughout the 1986 growing season and in mid-season in 1987. Patterns were similar for all species although absolute values varied considerably. Maximum stomatal conductance occurred early in the day and season during favorable environmental conditions and decreased as air temperature and the vapor pressure difference between the leaf and air increased. Maximum transpiration rates occurred in mid-morning and mid-summer resulting in estimated daily water losses per unit sunlit leaf area of 163-328 mol H2O …

An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith

Life Sciences Faculty Research

Five power generation plants along an eleven kilometer stretch divert Bishop Creek water for hydro-electric power. Stream diversion may be adversely affecting the riparian vegetation. Stable isotopic analysis is employed to determine surface water/ground-water interactions along the creek. surface water originates primarily from three headwater lakes. Discharge into Bishop Creek below the headwaters is primarily derived from ground water. The average δD and δ18O values are significantly different for surface water and ground water that an isotopic analysis can delineate between these two components of flow. Therefore isotopic shifts along the creek can determine gaining reaches. In addition, by knowing …

A Two-Dimensional Numerical Model Of The High Electron Mobility Transistor, Sze-Him Ng

UNLV Retrospective Theses & Dissertations

A two-dimensional numerical model of the high electron mobility transistor (HEMT) with consideration of quantization in the channel is presented. In this model, the spatial spread of the electron concentration in the quantum well normal to the heterojunction is taken into consideration by solving Schrodinger's and Poisson's equations self-consistently. The Boltzmann transport equation in the form of a current continuity equation and an energy transport equation is solved to obtain the transient transport behavior. Transport of carriers takes place in two layers in the GaAs region: the lowest subband of the quantum well and a non-quantized bulk layer; The simulation …

Dynamic Analysis Of Rotating Fan Structures By The Finite Element Method, Mohamed Said Rouas

UNLV Retrospective Theses & Dissertations

The Finite Element Method is used to determine the fundamental mode shapes and frequencies of fan structures. The analysis is performed on five fan structures, having different geometries, under static conditions and under centrifugal forces at various angular velocities. The results of the analysis are correlated with experimental data. The Southwell Coefficient, which takes into account the effect of centrifugal stiffening/softening, is determined for each fan and used for the prediction of its dynamic response and critical speeds. The research led to a study of the influence of riveted spider-to-blade connections on the vibration response of propeller fans; This thesis …

Decoupling And Adaptive Control And Stabilization Of Two-Link Elastic Robotic Arm, Arijit Das

UNLV Retrospective Theses & Dissertations

In this thesis the control and stabilization of a two link flexible robotic arm is considered. The first scheme is based on nonlinear inversion, a nonlinear controller is designed for the trajectory control of the joint angles using joint torquers. The inverse controller includes a servocompensator for robustness. A simplified controller has also been designed neglecting the Coriolis and Centrifugal forces; In the second scheme the control system design is based on nonlinear adaptive control and linear stabilization. First a nonlinear adaptive control law is derived such that in the closed-loop system the joint-angles are precisely controlled to track reference …

Analyses Of The Structure And Function Of Lower Colorado River Riparian Plant Communities, David E Busch

UNLV Retrospective Theses & Dissertations

Throughout western North America, riparian ecosystem function has been transformed by anthropogenic influences on riverine environments. Modified flood frequencies, durations or intensities, depressed floodplain water tables, and increased rhizosphere salinities contribute to change in communities formerly dominated by alluvial forest taxa. In addition, the invasion of a naturalized arborescent shrub, Tamarix ramosissima, potentially alters competitive hierarchies and disturbance regimes in riparian ecosystems. To evaluate southwestern riparian community structure and function, comparison of ecophysiological characteristics of dominant woody taxa with site physical parameters was undertaken in riparian ecosystems that are relatively pristine (Bill Williams River) and highly perturbed (lower Colorado River). …

The Principal's Role In The Development Of Teacher Leadership: A Case Study, Carla Jean Steinforth

UNLV Retrospective Theses & Dissertations

This study explored the principal's role in the development of teacher leadership in a school in the process of change. The single, case study was conducted in a large urban elementary school, grades K-5, within a major, western metropolitan school district. The nature of teacher leadership was examined along with the actions, behaviors, and thoughts of the principal which fostered the development of teacher leadership. Change process activities that were influenced or facilitated by teacher leadership were also studied; Primary sources of data collection included field observations, document reviews, and interviews conducted on a regular basis for a period of …

Laboratory Investigation Of A Method For Determining In Situ Saturated Hydraulic Conductivity, Joel Stacey Hayworth

UNLV Retrospective Theses & Dissertations

A study was conducted to determine the applicability of a method for determining in situ saturated hydraulic conductivity in porous media. This method requires an accurate measurement of the horizontal port water speed through a section of a borehole packed with a porous material of known hydraulic conductivity. Analytical expressions describing the theoretical basis for the method were investigated, as was the sensitivity of these expressions to varied parameters; Experiments were designed and performed in an attempt to determine if the theory could be successfully applied in a laboratory setting. These experiments were conducted in a large flowchamber which simulates …

Maximum Oxygen Uptake Predicted From Submaximal Tests, Anne Renee Lindsay

UNLV Retrospective Theses & Dissertations

Two widely used tests for predicting max VO2 are the Astrand-Ryhming Nomogram (ARN) and the National YMCA bicycle ergometer test. While both tests predict max VO2 from heart rate and workload, the ARN also uses submaximal oxygen uptake as a parameter; The purpose of this study was to determine which of the 3 types of exercises used with the Astrand-Ryhming nomogram predicted max VO2 most accurately; Thirty subject's between the ages of 18 and 35 performed maximally on a treadmill and bicycle ergometer. Oxygen uptake and heart rate were measured at both maximal and submaximal workloads using open circuit spirometry …

Variable Structure And Ultimate Boundedness Control And Stabilization Of Flexible Robotic Systems, Perumal Jegan Nathan

UNLV Retrospective Theses & Dissertations

In this thesis we study the control of two link light weight elastic manipulator in the presence of uncertainty. The control of flexible robotic arm with uncertainty such as variable payload, joint angle frictional torque etc., is an interesting and important problem; Here we consider control of joint angles and stabilization of the flexible modes caused by the manuever of robotic arm by two methods. These are: (i) Variable Structure control and (ii) Nonlinear Ultimate Boundedness control. Nonlinear Ultimate Boundedness control is a continuous control wherein the joint angle tracking error is uniformly ultimately bounded in the closed-loop system; Analytical …

Object-Oriented Data Modeling, Donald W Baltz

UNLV Retrospective Theses & Dissertations

The object-oriented paradigm models local behavior, and to a lesser extent, the structure of a problem. Semantic data models describe structure and semantics. This thesis unifies the behavioral focus of the object-oriented paradigm with the structural and semantic focus of semantic data models. The approach contains expressive abstractions to model static and derived data, semantics, and behavior. The abstractions keep the data model closer to the problem domain, and can be translated into a relational (or other) implementation. The paper makes six contributions. First, a comprehensive set of data structuring abstractions are described. Second, the abstractions are compared to the …

The Dynamic Response Of A Flexible Three-Link Robot Using Strain Gages, Lagrange Polynomials, Fourier Series, And The Finite Element Analysis, Robert Frank Marceau

UNLV Retrospective Theses & Dissertations

This thesis presents theoretical and experimental methods for determining the static and dynamic response, in three dimensional space, of a flexible three-link robotic manipulator. The Links are designed to deform elastically under static and dynamic loads. Lagrange polynomials are derived to determine the defected shape of the robotic links. All coefficients of the Lagrange polynomials are functions of the elastic strain at three specific locations on each link. Strains are converted to voltage differentials and are read into a micro-computer through an A-to-D board system, where they are converted to digital strain values. Coefficients defining the damped response of the …

Visualization Of A Plane Sweep Algorithm For Construction Of The Visibility Graph For Robot Path Planning, Vikas B Patel

UNLV Retrospective Theses & Dissertations

Research and development work in robotics and industrial automation has prompted a need for efficient motion planning algorithms for collision avoidance. To build fully autonomous robots, these algorithms must also model the environment correctly and accurately to safely maneuver the robot around obstacles. The main focus of this thesis is on the following problem and its solution: Given a set of obstacles represented as polygons in two-dimensional space, determine the shortest, collision-free path from the source point of the robot to some destination point. A fast and efficient algorithm for solving this problem is based on a plane-sweeping technique and …

The Crisis In American Education: The Impact On Vocational Education, Barbara Ann Quade

UNLV Retrospective Theses & Dissertations

This thesis is an interpretation and evaluation of the problems in the American education system which is failing American citizens by annually producing thousands of illiterates. Moreover, schools are failing to provide an adequate number of skilled workers for government, the military, and business and industry, and that trend will continue unless a drastic restructuring of the entire school system takes place; The paper examines reports on the crisis in education, reviews problems of illiteracy and the impact on technical skills, details concerns of the military, business and industry, and interested individuals regarding the quality of education in the U.S. …

Analysis Of Hotel Guest Room Supply, Donald Walter Raymond

UNLV Retrospective Theses & Dissertations

"Analysis of Hotel Guest Room Supply" is an exploratory paper that develops both a methodology and a model for estimating the expected number of hotel rooms at a destination location (MSA). The expected number of hotel employees at a destination are estimated from US government data (1980 Census of the Population and County Business Patterns). The hotel employee estimates are used to determine the expected number of hotel guest rooms for a destination location. These estimates were also applied to a third model, inventory shortage, to determine if hotel guest room supply and demand were in a state of equilibrium. …