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1992

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Real Time Method For Remote Measurement Of Compressional Wave Attenuation, Darryl L. Debruin Jan 1992

Real Time Method For Remote Measurement Of Compressional Wave Attenuation, Darryl L. Debruin

Electronic Theses and Dissertations 1990 - 1999

An acoustic measurement system is developed to estimate the compressional wave attenuation of marine sediments in real time. A chirp sonar transmits filtered digital reflection data to a signal processing computer that processes the data on an AT&T DSP32C chip. The signal processing computer estimates and displays the center frequency of the processed pulse as it is attenuated by the ocean sediments. Wavelet modelling establishes the relationship between the center frequency shift and relaxation time, from which the sediment type and compressional wave attenuation are determined. Frequency contours from two different data sites demonstrate that the system is able to …

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Selectively Redundant File System, Joy L. Veradt Jan 1992

Selectively Redundant File System, Joy L. Veradt

Electronic Theses and Dissertations 1990 - 1999

Disk arrays have been proposed as a means of achieving high performance, reliability and availability in computer systems. This study looks at the RAID (Redundant Array of Inexpensive Disks) disk array architecture and its advantages and disadvantages for use in personal computer environments, specifically in terms of how data is protected (redundant information) and the tradeoff required to achieve that protection (sacrifice of disk capacity). It then proposes an alternative to achieving a real-time method of protecting a user's data, which involves the modification of an operating system's file system to implement selective redundancy at the file level. This approach, …

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Selection Of Manufacturing Tolerances For Open-Chain Mechanisms, Arun. Kumar Jan 1992

Selection Of Manufacturing Tolerances For Open-Chain Mechanisms, Arun. Kumar

Electronic Theses and Dissertations 1990 - 1999

Flexible manufacturing systems play an important role in modern industries. The equipment used in flexible manufacturing systems such as industrial robots, NC machines, conveyors etc. demand high performance and accuracies. The selection of manufacturing tolerances is critical in deciding the accuracy of the mechanism and the manufacturing cost. In the present work a new kinematic model for open-chain mechanism is proposed which will help the designer in selecting the manufacturing tolerances. The model allows the designer to estimate the manufacturing cost for the required accuracy. By using the model and the cost function, a set of tolerances can be estimated …

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Seeds Of The Suez Canal Crisis: United States-Egyptian Relations From 1950 To 1955. Egypt's Quest For Arms, Todd Paul Zimmerman Jan 1992

Seeds Of The Suez Canal Crisis: United States-Egyptian Relations From 1950 To 1955. Egypt's Quest For Arms, Todd Paul Zimmerman

Electronic Theses and Dissertations 1990 - 1999

On 26 July 1952 Gamal Abdul Nasser and the Revolutionary Command Council deposed the Egyptian monarchy. The new regime initially exhibited a pro-American attitude and requested armaments from the United States, but Washington had attached too many conditions. In addition, the American government feared that Egypt's nationalism might generate a pan-Arab nationalism that would disrupt the Western relationship with the Middle East. Frustrated with the lack of a positive American response and recognizing Egypt's vulnerability as a result of a February raid with Israel, Nasser sought and obtained armaments from the Soviet-bloc in September 1955. This permitted the Soviet Union, …

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Realization And Implementation Of Separable-In-Denominator Two-Dimensional Digital Filter, Ziqiang. Huang Jan 1992

Realization And Implementation Of Separable-In-Denominator Two-Dimensional Digital Filter, Ziqiang. Huang

Electronic Theses and Dissertations 1990 - 1999

In this thesis, a partial fraction expansion of a separable-in-denominator 2-D transfer function is given. Based on this expansion, several novel realizations of separable-in-denominator 2-D filter are provide. These realizations have the properties of highly parallel structure and improved throughput delay. The performance figures are given in the tables. A method of evaluation of quantization error of separable-in-denominator 2-D filter is also derived by using the residue method. Formulas for calculation of roundoff noise of proposed structures are provided. Two programs which can be used to calculate the roundoff noise of proposed structure are listed in the Appendix. To run …

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Sensitivity Analysis For Machine Cell Formation Using Mathematical Model And Computer Simulation, Ravi. Yelamanchi Jan 1992

Sensitivity Analysis For Machine Cell Formation Using Mathematical Model And Computer Simulation, Ravi. Yelamanchi

Electronic Theses and Dissertations 1990 - 1999

This thesis presents a mathematical model for the sensitivity analysis of machine cell formation. Computer programs in C were developed. A statistical simulation model is developed to test and verify the mathematical model. The data for machine cell formation in cellular manufacturing is organized in a machine component chart representing the machining requirements of parts in the product mix. The existing machine cell formation models treat the product mix as deterministic. To study the probabilistic nature of the cellular manufacturing, a sensitivity analysis model is presented. The model optimizes the formation of intercellular material handling cost for the machine cell …

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Stability Of An Elliptical Vortex In A Time-Dependent Strain Field, Marilyn P. Marshall Jan 1992

Stability Of An Elliptical Vortex In A Time-Dependent Strain Field, Marilyn P. Marshall

Electronic Theses and Dissertations 1990 - 1999

A theoretical study of the stability of two-dimensional elliptical vortices in a time-dependent, periodically varying external straining flow was conducted. The mean value of the oscillating straining flow was chosen so that the vortex would be stationary in the absence of fluctuations of the external field about the mean. If the frequency of straining is near to the natural frequency of the vortex for small-amplitude oscillations of the vortex core, so that the vortex is forced near its natural frequency, a resonance occurs such that the aspect ratio of the elliptical core boundary initially oscillates with an amplitude that increases …

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Settling Of Fine Particles, Hung Soo Kim Jan 1992

Settling Of Fine Particles, Hung Soo Kim

Electronic Theses and Dissertations 1990 - 1999

This study pertaining to the settling of fine particles is developed using various models and formulas. The model considers two layers, i.e, the suspension zone dominated by perikinetic flocculation and the settling zone governed by gravitational force. In the suspension zone, floc formation of fine particles is simulated by the maximum chain model in which floc parameters and fractal dimension are compared with existing data. In addition, fractal dimension is compared with that of the hierarchical model. The main assumption of the model is that any floc having sixteen particles outweighs Brownian force, and thus the floc starts falling down …

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Single Antepartum Mother's Lived Experience Of Receiving Care From The Father Of The Baby: A Phenomenological Perspective, Brenda Elizabeth Ream Jan 1992

Single Antepartum Mother's Lived Experience Of Receiving Care From The Father Of The Baby: A Phenomenological Perspective, Brenda Elizabeth Ream

Electronic Theses and Dissertations 1990 - 1999

The purpose of the study was to come to understand the experience of a caring interaction between a single mother and the father of the baby. A qualitative study from a phenomenological perspective was used, with eleven participants being interviewed. Significant statements from the interviews were analyzed according to the four steps developed by Giorgi (1985). A description of the meaningful experience was obtained which includes the common themes of caring and non-caring. The themes and the implications for nursing practice are discussed.

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Sound Generated Due To Vortical Flow Past A Forward Facing Step, Ravishankar. Gundlapalli Jan 1992

Sound Generated Due To Vortical Flow Past A Forward Facing Step, Ravishankar. Gundlapalli

Electronic Theses and Dissertations 1990 - 1999

The sound field associated with the motion of 2-dimensional finite core vortex past a forward facing step is obtained. A numerical scheme using Contour Dynamics technique and incompressible, inviscid equations of motion is developed to determine the evolution of the structure of the vortex, its path over the step and the radiated sound. An appropriate low-frequency Green's function is derived and the expression for the far field acoustic pressure as formulated by Mohring is used. The vortex structure evolves in the non-uniform flow in the vicinity of the step and under certain conditions is found to undergo significant deformation of …

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Study In Drought Physiology Of Four Xerophytic Turfgrasses, David Earl Wedge Jan 1992

Study In Drought Physiology Of Four Xerophytic Turfgrasses, David Earl Wedge

Electronic Theses and Dissertations 1990 - 1999

Home owners and local and regional governments in Florida desire low maintenance ground covers. Therefore four xerophytic turfgrasses were evaluated for persistence. Turfgrasses were grown since late July 1990, along an access road to a public park and Interstate 95 in West Palm Beach, Florida. Percent cover, leaf water potential, and quantitative chlorophyll levels were determined for commercial Argentine Bahiagrass (Paspalum notatum) and three experimental grasses: Bahiagrass cv. Rapid Cover Polycross (RCP-2) (Paspalum notatum); St. Augustinegrass cv. FX-10 (Stenotaphyrum secundatum); and Buffalograss cv. Prairie (Buchloe dactyloides) after 12 months of biweekly irrigation and natural rainfall. Argentine Bahiagrass and St. Augustinegrass …

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Spectroscopic Studies Of Zinc(1-X) Manganese(X) Sulfur, Xiaoming. Chen Jan 1992

Spectroscopic Studies Of Zinc(1-X) Manganese(X) Sulfur, Xiaoming. Chen

Electronic Theses and Dissertations 1990 - 1999

The optical properties of the diluted magnetic semiconductor Zn1-x MnxS have been studied by using photoluminescence emission, lifetime and excitation spectroscopies. In photoluminescence spectroscopy three bands were found peaking at 585 nm (yellow band), 650 nm (orange band) and 750 nm (red band). For the yellow and red bands the peak position changes little with Mn concentration. For the orange band the peak energy decreases with increasing Mn concentration. The lifetimes of the yellow, orange and red bands were found to be about 70, 50 and 7 mus. The results of the lifetime measurements support the assumption that there is …

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Structure And Motion Estimation From Image Sequences, Jen-Yu. Shieh Jan 1992

Structure And Motion Estimation From Image Sequences, Jen-Yu. Shieh

Electronic Theses and Dissertations 1990 - 1999

The objective of this dissertation is to develop effective algorithms for estimating the 3-D structure of a scene and its relative motion with respect to a camera or a pair of cameras from a sequence of images acquired by the cameras, under the assumption that the relative motion of the camera is small from one frame to another. This dissertation presents an approach of computing depth maps from an image sequence, which combines the direct depth estimation method with the optical flow based method. More specifically, optical flow on and near moving edges are computed using a correlation technique. The …

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Some Calculated Properties Of Beta Prime-Nickel Aluminum, Eric Lawrence Hines Jan 1992

Some Calculated Properties Of Beta Prime-Nickel Aluminum, Eric Lawrence Hines

Electronic Theses and Dissertations 1990 - 1999

The band structure, density of states, Fermi surface, bulk modulus and heat of formation were calculated for beta prime-NiAl using the SCF-LMTO-ASA method. The equilibrium lattice constant was also determined by minimizing the total energy. The angle-resolved and x-ray photocurrents from the valence bands were determined using the NEWPOOL and XPSI codes and the calculated spectra were compared with recent experimental measurements. In the former case, the calculations were carried out for the (001) surface using s-polarized light and included the experimentally observed relaxations of the top two layers with an Al termination. The overall agreement between the theoretical and …

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Split-Ticket Voting: An Analysis Of The 1980, 1984, And 1988 Elections, Candace L. Gunnarsson Jan 1992

Split-Ticket Voting: An Analysis Of The 1980, 1984, And 1988 Elections, Candace L. Gunnarsson

Electronic Theses and Dissertations 1990 - 1999

This thesis examines one aspect of the decline in partisanship--split-ticket voting. Vote choices in three presidential elections--1980, 1984, and 1988--were analyzed. Split-ticket voting was examined among four groups in the voting population: race, region, age, and social class. There were only limited differences in the inclination to vote split-tickets among the groups analyzed. Incumbency at the House and Senate level was considered to be a viable factor which increased split-ticket voting. The factor of incumbency did encourage split-ticket voting in House races. However, it was not as significant a factor in Senate races.

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Stochastic Earthquake Ground Motion Modeling, Ruichong. Zhang Jan 1992

Stochastic Earthquake Ground Motion Modeling, Ruichong. Zhang

Electronic Theses and Dissertations 1990 - 1999

A model for earthquake ground motion is developed in this dissertation using principles of geophysics and stochastics. The earth is idealized as being composed of horizontally stratified layers, with uniform physical properties for each layer. The seismic source is assumed to be the result of shear dislocation propagating on a fault line, which is further discretized into a series of point sources at equal intervals. The fundamental problem of the ground motion in a layered medium due to a point source at a given source location is first considered. The governing equations of three-dimensional wave motion in a uniform layer …

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Stress Intensity Factors And Weight Functions For Surface Cracks Using Boundary/Finite Element Alternating Methods, Ruijia. Mu Jan 1992

Stress Intensity Factors And Weight Functions For Surface Cracks Using Boundary/Finite Element Alternating Methods, Ruijia. Mu

Electronic Theses and Dissertations 1990 - 1999

In the present investigation, the boundary/finite element alternating methods are used to evaluate the stress intensity factors and weight functions for surface crack problems. For two dimensional problems, Westergaard stress functions are used to find the analytical solutions for an infinite plate with an embedded crack, subjected to crack face tractions, and the boundary element method for the numerical solution. The stress intensity factors and weight functions for an arbitrary plate with an edge crack subjected to mixed mode loads are obtained by the alternating technique. For three dimensional problems, an elliptical coordinate system and the gravity potential functions are …

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Synthesis And Structural Characterization Of Organometallic Tin-Containing Ionomers Based On A Copolymer Of Ethylene And Acrylic Acid, Fengchen He Jan 1992

Synthesis And Structural Characterization Of Organometallic Tin-Containing Ionomers Based On A Copolymer Of Ethylene And Acrylic Acid, Fengchen He

Electronic Theses and Dissertations 1990 - 1999

Tin-containing ionomers were synthesized by reaction of poly(ethylene/acrylic acid) with mono, di and trihalo-organostannanes using the interfacial condensation technique. The products contain tin ester bonding as evidenced by infrared and mass spectroscopy. They are insoluble but form tough transparent films on application of heat and pressure. The modified ionomer products were flexible with high degrees of substitution and contained both bridging and nonbridging structures with respect to bonding about the tin atom. The analogous products from poly(acrylic acid) were brittle with lower substitutions and contained on nonbridging structure.

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Study Of The Instruction Of Latin American Geography In Secondary Schools In Southeast Florida, Andrew Brian Peterson Jan 1992

Study Of The Instruction Of Latin American Geography In Secondary Schools In Southeast Florida, Andrew Brian Peterson

Electronic Theses and Dissertations 1990 - 1999

The instruction of Latin American topics in southeast Florida is crucial to the future of the region. Geographic education has traditionally suffered in the United States, and Florida is no exception. The demographics of southeast Florida are changing to reflect a greater proportion of Latin Americans. Social studies programs at the secondary level should reflect this change and treat Latin American groups fairly. Textbooks in use in the region are second best choices for Latin American topical coverage. Social studies educators in southeast Florida are aware of the growing importance of Latin America to the region, but in many cases …

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Study Of Return-To-Industry Experiences Of Florida Community College Vocational Faculty Between 1986 And 1990, David E. Sullivan Jan 1992

Study Of Return-To-Industry Experiences Of Florida Community College Vocational Faculty Between 1986 And 1990, David E. Sullivan

Electronic Theses and Dissertations 1990 - 1999

The survey research in this study was a delayed post-examination of characteristics and outcomes of return-to-industry experiences of vocational community college faculty in Florida. A questionnaire was sent in 1990 to all community college faculty who participated between 1986 and 1990 in the Florida Vocational In-Service and Business Exchange Program. The survey population included all persons who had received grants in support of return-to-industry experiences for faculty or institutional upgrading over the four-year period. The questionnaire designed for this study solicited information about measurable outcomes affecting the participants and their institutions following the experiences. Questionnaire responses indicated perceived outcomes of …

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Study Of The Significance Of Marlowe's Use Of The Unforgivable Sin As A Plot Device In "Dr. Faustus", Michael Carlton Rudasill Jan 1992

Study Of The Significance Of Marlowe's Use Of The Unforgivable Sin As A Plot Device In "Dr. Faustus", Michael Carlton Rudasill

Electronic Theses and Dissertations 1990 - 1999

A crucial turning point in Christopher Marlowe's play Dr. Faustus occurs within the Latin chant in the conjuring scene. It is Faustus's commission of what is within the Christian universe the only unforgivable sin: the blasphemy against the Holy Spirit. This blasphemy is noted by Mephostophilis and is a deliberate device used by the playwright to make the work an irreversible tragedy. This ominously important act gives the play a certain dread impetus as events build to a sadly predictable conclusion. After Faustus's unforgivable words redemption from death and hell is impossible within the Christian cosmology in which the play …

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Synthesis Of Thiadiazole- And Diazepine-Based Acyclonucleosides With Potential Anticancer Or Antiviral Activity, Zhenling Wang Jan 1992

Synthesis Of Thiadiazole- And Diazepine-Based Acyclonucleosides With Potential Anticancer Or Antiviral Activity, Zhenling Wang

Electronic Theses and Dissertations 1990 - 1999

Cancer is a large group of diseases characterized by uncontrolled growth and spread of abnormal cells. If the spread is not controlled or checked, it results in death. Cancer is one of the leading causes of death in Western societies. In the United States, cancer is the second leading killer. However, many cancers can be cured if detected early and treated promptly. This paper analyzes the synthesis of thiadiazole- and diazepine-based acyclonucleosides with potential anticancer or antiviral activity.

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The Establishment And Study Of Two Elasmobranch Cell Lines, James Christopher Poyer Jan 1992

The Establishment And Study Of Two Elasmobranch Cell Lines, James Christopher Poyer

Electronic Theses and Dissertations 1990 - 1999

The present study describes the first cell lines produced from members of class Chondrichthyes. Explants of brain tissue from Carcharhinus falciformis (silky shark) and Ginglymostoma cirratum (nurse shark) were incubated in a mammalian medium modified with the addition of urea, trimethylamine N-oxide, NaCl, and bovine serum. Primary monolayers were passaged with 0.025% trypsin in a modified saline solution. Silky shark cells grew optimally at 29C. The population doubling time for C. falciformis cells at passage 29 was 67 hours. For G. cirratum cells at passage 6 the population doubling was 84 hours. Silky shark cells grew over a broad range …

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The Adolescent's Experience Of Being Accepted By A Nurse, Jodi Karen Weissman Jan 1992

The Adolescent's Experience Of Being Accepted By A Nurse, Jodi Karen Weissman

Electronic Theses and Dissertations 1990 - 1999

This is a phenomenological research study of the adolescent's experience of being accepted by a nurse. Six adolescents were selected who acknowledged and articulated their experience of being accepted by a nurse. The conceptual framework is derived from Paterson and Zderad's (1988) Humanistic Theory of Nursing. van Manen's (1984) approach to phenomenology was used to guide this inquiry. Data were generated using exploratory, in-depth, face-to-face interviews. The adolescent's experience of being accepted by a nurse is expressed by three metathemes: (1) the nurse is a friend; (2) the nurse's caring helps the adolescent feel better; and (3) the adolescent feels …

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Teenagers' Perspectives Of Caring During Labor And Delivery, Sylvia. Sanderson Jan 1992

Teenagers' Perspectives Of Caring During Labor And Delivery, Sylvia. Sanderson

Electronic Theses and Dissertations 1990 - 1999

The problem of the study was to understand the experience of being cared for by a nurse during labor and delivery. The review of literature for the study examined research focusing on adolescents in labor and delivery, caring and adolescent pregnancy and caring from current nursing literature perspective. Recalled labor and delivery experiences were analyzed phenomenologically in order to extract the meaning of the experience. Five recently delivered primiparous mothers were interviewed. Interviews followed guidelines designed to elicit descriptions of nurse caring. Interviews were tape recorded and transcribed. Data were reduced through a search for themes, and analyzed using guidelines …

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Trim Analysis By Shooting And Finite Elements And Floquet Eigenanalysis By Qr And Subspace Iterations In Helicopter Dynamics, Nagari Shriranga Achar Jan 1992

Trim Analysis By Shooting And Finite Elements And Floquet Eigenanalysis By Qr And Subspace Iterations In Helicopter Dynamics, Nagari Shriranga Achar

Electronic Theses and Dissertations 1990 - 1999

The trim analysis for the initial state and control inputs that satisfy response periodicity and flight conditions, and the Floquet eigenanalysis for a few largest eigenvalues of the Floquet transition matrix (FTM) are investigated. In the trim analysis, the convergence of Newton iteration is investigated in computing the periodic initial state and control inputs sequentially and in parallel. The trim analysis uses the shooting method and two h-versions of temporal finite element methods, one based on displacement formulation and the other on mixed formulation of displacements and momenta. In each method, both the sequential and in-parallel schemes are used, and …

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Tool Wear Monitoring Using Artificial Neural Networks, Venkatesh. Kurapati Jan 1992

Tool Wear Monitoring Using Artificial Neural Networks, Venkatesh. Kurapati

Electronic Theses and Dissertations 1990 - 1999

An on-line scheme for monitoring tool wear in unmanned machining operations using artificial neural networks (ANNs) is proposed. Various configurations of ANNs are studied to increase the accuracy of tool wear estimation. With this aim three configurations of the ANNs namely, an ANN without memory, an ANN with one phase memory, and an ANN with two phase memory are considered. Each ANN is trained to associate an input vector which consists of values of cutting conditions, with an output vector containing flank wear as a single output. The training data and evaluation data is generated using the popular analytical tool …

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The Structure Of Values Synthesized From The Lived Experiences Of Agency Nurses, Wendy Lea Strews Jan 1992

The Structure Of Values Synthesized From The Lived Experiences Of Agency Nurses, Wendy Lea Strews

Electronic Theses and Dissertations 1990 - 1999

The purpose of this study was to identify nursing values from lived experiences of six nurses during interactions with patients. Nurses employed by nursing agencies were asked: "describe an interaction you have experienced with a patient that best represents your nursing values". Giorgi's method of interpretation for phenomenological studies was used to analyze the stories. From each participant's specific values a general description of the structure of all participants' values was generated. Caring was the predominant value that emerged and encompasses nursing practice and the compassionate action it teaches. Concepts emerging from the study are living and learning of values, …

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Transfer Effects Of A High School Computer Programming Course On Mathematical Modeling, Procedural Comprehension, And Verbal Problem Solution, Madeline Ann Bernardo Jan 1992

Transfer Effects Of A High School Computer Programming Course On Mathematical Modeling, Procedural Comprehension, And Verbal Problem Solution, Madeline Ann Bernardo

Electronic Theses and Dissertations 1990 - 1999

Computers are becoming an integral part of our high school curriculum. Students use computers for computer-assisted instruction (CAI), word processing, spreadsheet and database applications, and computer programming. It is important to know the cognitive effects of each mode of computer use. The purpose of this study was to investigate transfer effects of a high school BASIC programming course on students' skills in mathematical modeling, procedural comprehension, and verbal problem solution. The sample consisted of 44 BASIC I students, 44 computer literacy students, and 44 students who had no computer training. Groups were matched on years of mathematics and on the …

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Thermal Modeling And Field Temperature Measurement Of Segmental Box Girder Bridges In Florida, Milind Madhukar Basole Jan 1992

Thermal Modeling And Field Temperature Measurement Of Segmental Box Girder Bridges In Florida, Milind Madhukar Basole

Electronic Theses and Dissertations 1990 - 1999

Temperature and thermal stress variations in a segmental box girder bridge arc studied. A finite element model using the general finite element software MARC is used to predict temperature and thermal stress variation, for segmental box girder bridges. The predictions are compared with actual measured temperature data of two segmental box girder bridges, instrumented with thermocouples and vibrating wire strain gages, in Davie, Florida. Continuous monitoring was carried out for two months in July-August, 1991, and for one month in January-February, 1992. Comparison are also made with the NCHRP suggested profiles. A Monte Carlo analysis is performed to accommodate the …

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