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Graduate Theses, Dissertations, and Problem Reports (ETD)

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An Object Relationship Framework And Persistence In Java., Srinivas S. Vangari Jan 1998

An Object Relationship Framework And Persistence In Java., Srinivas S. Vangari

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main objective of this thesis is to provide the design and implementation of an object relationship framework in Java where objects can form relationships with other objects dynamically at runtime. Relationships among objects have long been recognized as the important semantic constructs facilitating ease of analysis & design of large complex systems. Almost all modeling techniques have notations to describe the existence of relationships among software components. But unfortunately the relationships identified in analysis stage could not be mapped to the equivalent high-level language constructs during the implementation because of lack of high level semantic support for relationships in …

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Dynamic Response Of The Human Skull-Brain Complex To Impact: Points Of Maximum Stress And Pressure., Rinitha Palkamsetty Jan 1998

Dynamic Response Of The Human Skull-Brain Complex To Impact: Points Of Maximum Stress And Pressure., Rinitha Palkamsetty

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study addresses the transient dynamic response of a human skull-brain complex under impact loads. Three cross-sections; sagittal, transverse and coronal of the brain are considered to perform the transient dynamic analysis that describes the kinematics and stress wave patterns of the internal motions in the skull and brain mass. The models include cerebral spinal fluid and meningi membrane along with the skull and the viscoelastic brain tissue. The analysis is performed using the program LS-DYNA3D for the analysis of frontal, lateral and top impact. The results produced include the loci of points that carry the maximum stresses as the …

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A Study Of Impact Using 80-Derometer Rubber., Steven Harold Howard Jan 1998

A Study Of Impact Using 80-Derometer Rubber., Steven Harold Howard

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this work was to model and test an intermediate material that would absorb impact loads induced during deployment of a deployable rollover protective structure (ROPS) designed for use on a farm tractor. The design criteria required that the intermediate material, under compressive loads, maintain the integrity of all moving parts while introducing a minimum impact time of 0.005 seconds. A "ring" shaped part made of 80-Derometer rubber (a product of the Goodyear Corporation) was incorporated into the impact region of the ROPS deployment mechanism. Theoretical calculations were made based on energy balance equations and 2-D Working Model …

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The Relationships Among Hypermedia-Based Instruction, Cognitive Styles And Teaching Subject-Verb Agreement To Adult Esl Learners., Fuqiang Zhuo Jan 1998

The Relationships Among Hypermedia-Based Instruction, Cognitive Styles And Teaching Subject-Verb Agreement To Adult Esl Learners., Fuqiang Zhuo

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examines the relationships among hypermedia-based instruction, cognitive styles, and teaching subject-verb agreement to adult ESL learners in order to find an effective approach to teach grammar which is a very thorny issue in the field of second and foreign language instruction and learning. Therefore, the effect of hypermedia on grammar instruction and learning is the main focus in this study. The treatment was the employment of hypermedia creating a new learning environment in which the adult ESL learners could be benefited from the advantages of new technology. Based on the current methodologies, approaches, and principles of second and …

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Symbolic Behavior: Reorganizing And Expanding Stimulus Classes Through Matching And Naming., Oliver Wirth Jan 1998

Symbolic Behavior: Reorganizing And Expanding Stimulus Classes Through Matching And Naming., Oliver Wirth

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of the present study was to further clarify the structural and functional properties of stimulus equivalence classes and functional stimulus classes relative to the procedures that establish them. With college students, stimulus equivalence classes were established using a standard selection-based matching-to-sample (MTS) procedure, and functional stimulus classes were established using a topography-based naming task. During the naming trials, students were trained to say distinct nonsense words in the presence of arbitrarily assigned sets of symbols. Computer-controlled voice-recognition software was used to record and analyze students' vocal responses for accuracy and speed. Experiment 1 examined whether stimulus equivalence classes …

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Performance Of Flexible Pavements Reinforced With Geogrids., Bora Kutuk Jan 1998

Performance Of Flexible Pavements Reinforced With Geogrids., Bora Kutuk

Graduate Theses, Dissertations, and Problem Reports (ETD)

This report presents the results of an investigation on the effectiveness of glass fiber grids as a reinforcement of the asphalt base layer in a flexible pavement. The study involved both laboratory experimental work and computer analysis of pavement sections. As part of the experimental work, twenty flexible pavement sections (with and without glass fiber grids) were constructed and tested in the laboratory. The laboratory-scale pavement sections were instrumented with pressure cells, displacement gages, and strain gages. Test sections were subjected to 1,000,000 load applications at a frequency of 1.2 Hz. Static loading tests were conducted at intervals of 100,000 …

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Water Demand Management For Casablanca, Morocco., Mohamed Lahlou Jan 1998

Water Demand Management For Casablanca, Morocco., Mohamed Lahlou

Graduate Theses, Dissertations, and Problem Reports (ETD)

Water shortages could significantly curtail economic growth and development in Casablanca, Morocco. Conservation programs in Morocco have been implemented only occasionally, usually during a water shortage crisis arising either from technical reasons or from drought. Public awareness activities suffer from a lack of effectiveness and do not fulfill the desired objectives. The purposes of this study are to examine water consumption characteristics in Casablanca and develop approaches for water management to help assure that shortages will not undermine the prospects for sustainable economic development. Research procedures used were the development and estimation of water demand models for the residential/commercial, industrial, …

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A Description Of The Instructional And Assessment Practices Of Selected Elementary Teachers., Mary D. Morris Jan 1998

A Description Of The Instructional And Assessment Practices Of Selected Elementary Teachers., Mary D. Morris

Graduate Theses, Dissertations, and Problem Reports (ETD)

Three distinct teachers, recognized by their administrators as excellent, were chosen to participate in a study designed to describe a recent phenomena in education. All three teachers were members of a faculty that was recognized as a Professional Development School in collaboration with the Benedum Foundation. Traditionally educators have looked to their local school district to provide continuing education. This professional development covers a wide range of topics and is given with a random approach. Recently there have been schools that have decided that their instruction and assessment could change to incorporate more alternative methods to accommodate a variety of …

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Evaluation Of The Effect Of Temporal Variations In Flow Patterns On Capacity Design For Underground Coal Mine Belt Systems., Xueming Wang Jan 1998

Evaluation Of The Effect Of Temporal Variations In Flow Patterns On Capacity Design For Underground Coal Mine Belt Systems., Xueming Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Belt conveyor haulage systems are critical to keep an underground-coal mine running profitably. It is not easy to design a reliable and efficient system. The issues associated with designing the capacity for a belt conveyor and a bunker are addressed in this dissertation. Several design models have been discussed, and discrete-event simulation models are recommended as the most flexible and useful tools. Most of the simulation models require the use of a step-function model to describe the loading process at each loading point. Over the years, simulation practitioners have generally employed one of the three conventional models, the peak loading …

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The Relationship Between Gender, Faculty Development, And Class Size And Sense Of Efficacy Of College Mathematics Teachers., Beth Cipoletti Jan 1998

The Relationship Between Gender, Faculty Development, And Class Size And Sense Of Efficacy Of College Mathematics Teachers., Beth Cipoletti

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine the relationship between gender of the teacher, faculty development, and class size of college mathematics teachers. The population for this study were 272 randomly selected institutions nationwide granting degrees in mathematics. A survey packet with a cover letter, a copy of the Teacher Efficacy Scale (Gibson & Dembo, 1984), and a questionnaire was mailed to the mathematics departments at each of the selected institutions. The recipient of the mailing was asked to either complete the enclosed instruments or forward the packet to a fellow full-time mathematics teacher. The return rate was 46%. …

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Cardinal Numbers Connected With Adding Darboux-Like Functions., Francis Edmund Jordan Jan 1998

Cardinal Numbers Connected With Adding Darboux-Like Functions., Francis Edmund Jordan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Let {dollar}F\\subseteq\\IR\\sp\\IR.{dollar} The additivity A(F) of F is the minimum cardinality of a family {dollar}G\\subseteq\\IR\\sp\\IR{dollar} with the property that {dollar}h\\ +\\ G\\subseteq F{dollar} for no {dollar}h\\in\\IR\\sp\\IR.{dollar} The additivities of various families of functions which generalize some aspect of continuity are known. These families, referred to as the Darboux-like functions, include the almost continuous, Darboux, connectivity, perfect road, peripherally continuous, and extendable functions. The additivities of the complements of the Darboux-like families are calculated or estimated. If {dollar}F\\subseteq\\IR\\sp\\IR{dollar} the additivity of {dollar}\\IR\\sp\\IR\\\\ F{dollar} is the minimum cardinality of a family {dollar}G\\subseteq\\IR\\sp\\IR{dollar} with the property that {dollar}(h + G)\\cap F\ot=\\emptyset{dollar} for every …

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Development Of A Tolerance Design Model In Manufacturing Assembly And Design Of Cost-Based Cusum Control Charts Using Taguchi Quality Loss Function., Jung-Dae Kim Jan 1998

Development Of A Tolerance Design Model In Manufacturing Assembly And Design Of Cost-Based Cusum Control Charts Using Taguchi Quality Loss Function., Jung-Dae Kim

Graduate Theses, Dissertations, and Problem Reports (ETD)

The quadratic loss function has been used in the statistical and control theory literature. Taguchi applied quadratic loss function to quality improvement. His quality loss function has been known to be effective in assessing quality loss in monetary terms, while most of the traditional quality control techniques, such as tolerance design and control chart design, use estimated cost factors. Taguchi's quality loss function concept is different from traditional methods in which all the values within the specification limits are equally acceptable. However, his idea is that for many products, parts elements and components, a target or nominal size or value …

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Thermal Stress Prediction For Direct-Chill Casting Of A High Strength Aluminum Alloy., Jian Wan Jan 1998

Thermal Stress Prediction For Direct-Chill Casting Of A High Strength Aluminum Alloy., Jian Wan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Direct chill (D.C.) casting is one of the most important semi-continuous methods for the production of high strength aluminum alloys. The enormous unevenly cooling of ingots during the casting process can cause significant thermally induced stresses, which may result in solidification cracking. The control of the cracking during DC casting is a state-of-art technology, and many finite element models have been applied to simulate the solidification process during ingot casting. So far, most of the simulations can predict the thermal fields of the ingot accurately, but very few works can get satisfactory thermal stress profiles. One of the major difficulties …

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Choice, Changing Over, And Reinforcement Delay., Timothy Alan Shahan Jan 1998

Choice, Changing Over, And Reinforcement Delay., Timothy Alan Shahan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The independent effects of two normally confounded delays to reinforcement produced by changing between concurrent variable-interval schedules of reinforcement were examined with pigeons. In Experiments 1 and 2, combinations of changeover delays and fixed-interval travel requirements were arranged for changeovers in a changeover-key concurrent schedule procedure. The delay from a changeover-produced change in stimulus conditions to a reinforcer was varied while the delay between the last response on one alternative and a reinforcer on the other (the total obtained delay) was held constant. Changeover rates decreased as a negative power function of the total obtained delay. The delay between a …

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Foundations Of Object-Based Specification Design, David March Fleming Dec 1997

Foundations Of Object-Based Specification Design, David March Fleming

Graduate Theses, Dissertations, and Problem Reports (ETD)

To enhance applicability and encourage its use, a component or a component-based system must have a well-designed set of interface features as well as a proper explanation of these features. The dual problem of designing a suitable set of interface features in addition to properly explaining its behavior is termed the specification design problem. This dissertation identifies observability, controllability, and a performance-motivated pragmatic criterion as essential properties of desirable formal specifications for reusable object-based software components. The pragmatic criterion guides the design of component interfaces and component libraries to a suitable set of features so that they are widely applicable, …

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A Signal Detection Analysis Of Body Image Distortion Among Women With Bulimia Nervosa., Lynda Anne Szymanski Jan 1997

A Signal Detection Analysis Of Body Image Distortion Among Women With Bulimia Nervosa., Lynda Anne Szymanski

Graduate Theses, Dissertations, and Problem Reports (ETD)

The clinical conceptualization of body-image distortion among persons with eating disorders typically emphasizes sensory disturbances and de-emphasizes nonsensory, environmental variables. The present study examined body-size misperceptions using a signal detection paradigm in 20 women with bulimia and 20 women without present symptomology or history of an eating disorder. First, subjects estimated their body sizes using a video distortion camera. Second, each subject judged how similar or dissimilar each of 192 distorted and undistorted images was to her actual body size using a 5-point rating scale. The second phase of the study was repeated with one-half of the subjects given instructions …

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Identifying Barriers To Computer-Supported Instruction., Ragina Melton Copeland Jan 1997

Identifying Barriers To Computer-Supported Instruction., Ragina Melton Copeland

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was designed to determine if 1996 high school seniors who enrolled at West Virginia University at Parkersburg in the fall of 1996 were receiving equal educational opportunity with a focus on computer access and usage. The data collection consisted of two major parts: surveying the students in the 7-county service area of WVUP and interviewing at least 5 teachers or other professional staff from among each of the 11 schools located in 7 different counties. The findings of the study showed that students did not enjoy equal access to computers and computer instruction and that a combination of …

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Interface Load: Deformation Behavior Of Landfill Liner Systems Over Subsurface Cavities., Ghada Shaker Ellithy Jan 1997

Interface Load: Deformation Behavior Of Landfill Liner Systems Over Subsurface Cavities., Ghada Shaker Ellithy

Graduate Theses, Dissertations, and Problem Reports (ETD)

The leachate collection system and the double liner required by the EPA for solid and hazardous waste landfills consist typically of a combination of geosynthetics materials and natural or processed soils. This research is conducted to study the load-deformation behavior of a multi layered landfill liner system under stresses imposed by the waste fill. Experimental and analytical work achieved in this research is summarized as follows: (1) Experimental Evaluation of the shear stress-shear deformation characteristics of seven geosynthetic interfaces encountered in landfill lining systems in addition to four geosynthetic materials and three soils. The investigated materials included: Ottawa sand, kaoline …

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Broiler Exports: A Structural Time Series Approach., Crispin Mutshipayi Kapombe Jan 1997

Broiler Exports: A Structural Time Series Approach., Crispin Mutshipayi Kapombe

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study's central purpose is to provide information that can be used to help understand and, thus, increase U.S. exports of poultry products. It emphasizes international broiler market responsiveness to U.S. export prices, the impact of currency realignments on imports from the U.S. (exchange rate impacts), per capita incomes of importing countries, the prices of substitutes, and government interventions in poultry markets. To investigate the interrelated U.S. broiler export market, a multiple equation econometric model of U.S. broiler exports is developed. The theoretical framework of the broiler exports model is the structural time series model (STSM), developed by Harvey and …

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Role Expectations And Predictions Of Trends For Human Resource Development At Small, Private Colleges And Universities Within The Southern Regional Education Board Area., Beth Ann Triplett Jan 1997

Role Expectations And Predictions Of Trends For Human Resource Development At Small, Private Colleges And Universities Within The Southern Regional Education Board Area., Beth Ann Triplett

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was designed to identify the role expectations, reporting hierarchy, years in role and trends in human resource development (HRD) as reported by the person responsible for HRD in small, private colleges and universities within the Southern Regional Education Board (SREB) geographic area. The population for this study was all the four-year, small, private schools in Southern Regional Education Board (SREB) states (N = 200). Each institution in the sample was mailed a copy of the HRD Roles Survey, an instrument developed for the purpose of this research. The survey was based on data from the American Society for …

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Decentralized Estimation For Large Scale Interconnected Systems., Noureddine Bekhouche Jan 1997

Decentralized Estimation For Large Scale Interconnected Systems., Noureddine Bekhouche

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation deals with the design of decentralized estimators for large scale interconnected systems. The systems are composed of several subsystems interconnected together. At each subsystem level a filter is designed to estimate local and/or interface variables. Kalman filtering and H{dollar}\\infty{dollar} filtering tools are used to derive decentralized estimators based on two different approaches namely, direct and indirect methods. A power system application is used to illustrate the proposed algorithms. In each method the decentralized filter design requires a subsystem model (local model) and a set of measurements. In the direct method additional measurements are needed for decentralization. In the …

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A Modified Research Approach Teaching Style In A High School Chemistry Classroom., Krystal D. Curtis Jan 1997

A Modified Research Approach Teaching Style In A High School Chemistry Classroom., Krystal D. Curtis

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to develop a teaching style that used a modified research approach in a high school chemistry classroom. This modified research approach involved constructivist teaching practices, particularly the learning cycle. It emphasized the development of student science process skills, the mastery of science content, and a better understanding of attitudes about science in the classroom. It also promotes active learning in the classroom. The study also looks at the effectiveness of implementation of this teaching style. The methodology of the study involved designing modules which centered around nine basic chemistry concepts. These modules were guided …

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A General Statistical Approach To Engineering Problem Solving., Ali Akbar Moshirpour Jan 1997

A General Statistical Approach To Engineering Problem Solving., Ali Akbar Moshirpour

Graduate Theses, Dissertations, and Problem Reports (ETD)

A non-deterministic approach to engineering problem solving is developed, with the emphasis on the effects of manufacturing and service uncertainties on selected performance characteristics and economic factors. The approach integrates concepts from probability analysis, statistical inference, and decision making theory into a coherent framework, which is identified here as the Decision Model for Engineering (DME). The main innovative aspect of this approach is the application of a general method for statistical inference based on the Bayes' theorem to quantify probabilities of random variables for subsequent use as inputs to a decision making model. The solution to a Bayesian inference problem …

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Analysis And Design Optimization Of Fiber-Reinforced Plastic (Frp) Structural Beams., Pizhong Qiao Jan 1997

Analysis And Design Optimization Of Fiber-Reinforced Plastic (Frp) Structural Beams., Pizhong Qiao

Graduate Theses, Dissertations, and Problem Reports (ETD)

Considering current and future applications of composite materials in civil engineering structures, a need exists for developing a design analysis and optimization approach for FRP shapes to improve their performance efficiency and competitiveness in relation to conventional materials. An analytical approach for design of pultruded FRP shapes under bending is proposed, and based on this approach, a computer program is developed to carry out the analysis of FRP sections. This analytical approach combines micro/macromechanics analyses with the Mechanics of thin-walled Laminated composite Beam model (MLB) to evaluate the response of existing pultruded FRP beams. Based on buckling analyses of individual …

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Computational Modelling Of Tube Production Process For Nickel-Base Alloys., Young Ryul Kim Jan 1997

Computational Modelling Of Tube Production Process For Nickel-Base Alloys., Young Ryul Kim

Graduate Theses, Dissertations, and Problem Reports (ETD)

Numerical modelling simulations of two dimensional tube extrusion and three dimensional tube pilgering reduction of nickel-base alloys were conducted using a commercial finite element code, DEFORM{dollar}\\sp{lcub}\\rm TM{rcub}{dollar}. Accuracy of the finite element modelling results was verified quantitatively by comparing solid extrusion simulation results with experimental data. An interface frictional coefficient was also examined and the best fit was selected for the simulation. As expected, heat loss of the extruded material was found to be significant due to temperature-dependent material properties of the alloy. A sequence of selected FEM tube extrusion simulations using DEFORM{dollar}\\sp{lcub}\\rm TM{rcub}{dollar} were carried out and based on …

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Estimation Of The Longitudinal And Lateral-Directional Aerodynamic Parameters From Flight Data For The Nasa F/A-18 Harv., Alfonso Christopher Paris Jan 1997

Estimation Of The Longitudinal And Lateral-Directional Aerodynamic Parameters From Flight Data For The Nasa F/A-18 Harv., Alfonso Christopher Paris

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research is focused on parameter identification for the NASA F/A-18 HARV. The HARV is currently used in the high alpha research program at the NASA Dryden Flight Research Center. In this study the longitudinal and lateral-directional stability derivatives are estimated from flight data using the Maximum Likelihood method coupled with a Newton-Raphson minimization technique. The estimated aerodynamic model describes the aircraft dynamics over a range of angle of attack from 10{dollar}\\sp\\circ{dollar} to 60{dollar}\\sp\\circ{dollar}. The mathematical model is built using the traditional static and dynamic derivative buildup. Flight data examined in this analysis are from a variety of maneuvers including …

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Integrating Technology Education Concepts Into China's Educational System., Faxian Yang Jan 1997

Integrating Technology Education Concepts Into China's Educational System., Faxian Yang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The problem of this study was to develop a strategy for integrating technology education concepts within the Chinese mathematics and science curricula. The researcher used a case study as the basic methodology. It included three methods for collecting data: literature review, field study in junior and senior secondary schools in America and China, and interviews with experienced educators who were familiar with the status of technology education programs in the selected countries. The data came from the following areas: Japan, Taiwan, the United Kingdom, China, and five states in the United States: Illinois, Iowa, Maryland, Massachusetts, and New York. The …

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Application Of Automotive Engine Control Technology To General Aviation Aircraft Powerplants., Christopher John Tennant Jan 1997

Application Of Automotive Engine Control Technology To General Aviation Aircraft Powerplants., Christopher John Tennant

Graduate Theses, Dissertations, and Problem Reports (ETD)

The general aviation industry has lagged behind the automotive industry in powerplant development due to depressed economic conditions in their marketplace. Recent efforts to revitalize the industry have encountered the hindrance of thirty-year-old engine technology. Current automotive engine control technology has been reviewed for its potential for transfer to existing general aviation powerplants. Current automotive engine control technology was classified into basic, correction, and feedback elements for the control of fuel flow and ignition timing. The value of each element was assessed for application to a general aviation powerplant in terms of an aviation duty cycle. An extensive database produced …

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Computer Programming: Science, Art, Or Both?, Sandra Trent Gum Jan 1997

Computer Programming: Science, Art, Or Both?, Sandra Trent Gum

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to determine if spatial intelligence contributes to a student's success in a computer science major or if mathematical-logical intelligence is sufficient data on which to base a prediction of success. The study was performed at a small university. The sample consisted of 15 computer science (CS) majors, enrolled in a computer science class, and 15 non-CS-majors, enrolled in a statistics class. Seven of the CS-majors were considered advanced and seven were considered less advanced. The independent measures were: the mathematics and the English scores from the ACT/SAT (CS-majors); a questionnaire to obtain personal information; …

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Intensive Supervised Probation And Institutional Placements For Adjudicated Youth: A Closer Look., Cleaster Marie Jackson Jan 1997

Intensive Supervised Probation And Institutional Placements For Adjudicated Youth: A Closer Look., Cleaster Marie Jackson

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the alarming rate of school violence and teen crime public outcry demands that we look for immediate remedies to make schools and communities safe. One solution which has received public support is the current trend to solve this problem by building more juvenile facilities to house these youth. This short term fix, which has been referred to as an "out of sight out of mind mentality" creates other concerns such as loss of educational dollars to public schools and highlights the lack of commitment to provide effective programs to meet the needs of challenging students. The purpose of this …

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