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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
351

Instructional management profiles the relationship between teaching styles, grade level preferences, and related factors /

McNaughton, Amy K. January 2007 (has links)
Thesis (D.Min.)--Liberty Theological Seminary and Graduate School, 2007.
352

Predicting instrument detection efficiency when scanning small area radiation sources

Hart, Kevin G. 26 April 2002 (has links)
Accurate quantification of radionuclides detected during a scanning survey relies on an appropriately determined scan efficiency calibration factor (SECF). Traditionally, instrument efficiency was determined from a fixed instrument to source geometry. However, as is often the case, the instrument is used in a scanning mode where the source to instrument geometry is dynamic during the observation interval. Three separate procedures were developed to determine the SECF for a 10 cm x 10 cm source passing under the centerline of a 12.7 cm x 7.62 cm NaI(T1) detector. The procedures were first tested for determining the SECF from a series of static point source measurements generated by the Monte Carlo N-Particle (MCNP) code. These static efficiency values were then used to predict the SECF for scan speeds ranging from 10 cm s����� to 80 cm s����� with a one second observation interval. The investigator then used MCNP to directly determine the SECF by simulating a scan of a 10 cm x 10 cm area source for scan speeds ranging from 10 cm s����� to 80 cm s�����. Comparison of the MCNP static simulation with the scan simulation showed the accuracy of the SECF prediction procedures to be within ��5%. Experimental results further show the three procedures developed to predict the actual SECF for a 10 cm x 10 cm source to be accurate to within ��10%. Besides the obvious application to determine an SECF for a given scan speed, this method can be used to determine the maximum detector or source velocity for a desired SECF. These procedures are effective and can likely be extended to determine an instrument specific SECF for a range of source sizes, scan speeds, and instrument observation intervals. / Graduation date: 2002
353

Quality of learning in primary care : a social systems inquiry

Kailin, David C. 02 May 2002 (has links)
What constitutes quality of learning in primary care? A social systems view of that central question regards the relationships between dimensions of learning, purposes of primary care, and quality of practice. The question of learning quality was approached in three ways. First, perceptions of learning quality were elicited through recorded interviews with fifteen participants representing diverse roles in a primary care medical clinic. Analysis of the interviews indicated learning sources, factors, and functional dimensions of learning. Second, because learning is constituted in a social practice, the social context of learning in primary care clinics was modeled with qualitative systems diagrams. This exposed systemic barriers and facilitators of learning in practice. Third, learning is directed toward fulfilling the purposes of primary care. The nature of those purposes is not well articulated. A framework of seven core purposes was developed from the perspective of systems phenomenology. This framework extends the biopsychosocial framework in several regards. Perceptions of learning quality, the structural situation of learning in clinical practice, and the core purposes of primary care, all contribute to a social systems understanding of what constitutes learning quality, and how primary care organizations might procure it and assess it. Systems phenomenology represents a significant innovation in social systems science methods. / Graduation date: 2002
354

Failure analysis of Muller-C-element

Chew, Oonpin 05 August 1996 (has links)
Asynchronous circuits have recently been a breakthrough in many high performance computers. The concept of asynchronous circuits which started a long time ago has slowly grasped the attention of many designers. The Muller-C-element is an important control block in many asynchronous designs and therefore it is important to understand some of the possible failures that might occur in this circuit. The timing and behavior of this element will have an important effect on the overall performance of the system. The purpose of this research is to study some of the common failures that exist in synchronous logic and find out if these failures can also happen in the C-element. Condition for a failure must be present in order for it to occur. Understanding the conditions required for a circuit failure to occur, we will show realistic examples in the applications of C-element in which such similar conditions will also happen. In this thesis, we are interested in analyzing the circuit failures in C-element due to different logic threshold voltages of different devices, problem of charge-sharing and metastabilty characteristic of circuit. Simulations results will show such failures does occur in the C-element when the conditions were met. / Graduation date: 1997
355

Evaluation of cathodic protection in reinforced concrete bridges

Abooameri, Farid 28 September 1994 (has links)
Steel corrosion in reinforced concrete is a major concern to transportation agencies nationwide because of the expenses incurred for repair and ultimate shortening of bridge life. Cathodic protection (CP), as a remedy, has been applied to reinforced bridges in the US since 1974. However, application of this technique is largely empirical, lacking fundamental understanding. In order to optimize the performance of a CP system, it is important to monitor the rebar potential with respect to a reliable reference electrode. Moreover, because of potential variation in the concrete, reference cell placement is fundamental to ensure effective protection. The work plan was divided into two parts: laboratory scale experimentation and computer simulation. In the experimentation section, the response of graphite probes was compared to that of an Orion silver-silver chloride electrode. Graphite probes behaved as well as the standard electrode. Furthermore, the home-made graphite probes behaved the same as the commercial ones. This will allow much greater experimental latitude since the home-made probes are much more economical than the commercial ones. A finite difference code was developed to assess the performance of cathodic protection. The potential distribution in a two dimensional geometry of a concrete block with a sprayed zinc anode at one boundary and an iron cathode at the other side was calculated under cathodic protection. The equations were solved by means of a Gauss-Seidel iterative method with the help of an overrelaxation factor. An interval halving method was used to solve for nonlinear boundary condition at the iron. The effects of concrete pore saturation, concrete cover, and applied potential were studied to determine the degree of protection and proper placement of the reference electrode in concrete. Furthermore, a sensitivity analysis was performed versus input parameters: concrete conductivity, oxygen mass transfer coefficient, and oxygen reduction polarization parameters. The results of the simulation showed that the center of the rebar is less protected than the other locations. Therefore, the reference electrode should be located as close to the center as possible. / Graduation date: 1995
356

A kinetic and kinematic comparison of the grab and track starts in competitive swimming

Juergens, Cheryl A. 24 October 1994 (has links)
In competitive swimming a spread in time of only 0.10, and 0.16 seconds constituted the difference between finishing second and seventh, and first and eighth, respectively, in the women's 50 yard freestyle at the 1993 NCAA Division III National Swimming & Diving Championships. Based on data collected over a period of years Maglischo (1993) noted that "improving the start can reduce race times by at least 0.10 second" (p. 544). Therefore it is beneficial to the outcome of a race to direct attention to maximizing the effectiveness of the racing start. The primary purpose of this study therefore was to compare kinetic and kinematic components of the grab and track style starts. During the past two decades extensive kinematic research has been done using cinematography. These studies used time, velocity, displacement, and the measure of angles (i.e. at takeoff and entry) to measure the relative effectiveness of various racing starts. Conversely, there has been limited analysis of racing starts using kinetic measurements. Four kinetic and five kinematic variables were evaluated in this study to compare the relative effectiveness of the starting techniques. Ten female varsity swimmers, who had used both starts interchangeably in competition, were selected for this study. Force components were obtained directly from a Kistler force platform. Block time, horizontal and vertical impulse, and average horizontal and vertical force values were obtained in subsequent analysis of the Force-time data. Each subject was videotaped as she executed three trials of each start. The video data were digitized and then analyzed using two dimensional video analysis techniques. The type of start technique used on each trial was randomly ordered. Kinematic variables of horizontal and vertical displacement of the center of mass, average horizontal velocity and vertical velocity were also obtained from the video data in order to determine which of the two starting techniques (i.e. grab vs. track) was the most effective. 2x10 (starting technique x subject) repeated measures Analyses of Variance indicated significant differences (p<0.01) between the starting styles for five of the nine dependent variables measured which provided support for the original contention that the track style start was the more effective of the two racing start techniques investigated. The results of this study provide support to the empirical and observational findings of earlier researchers. / Graduation date: 1995
357

Evaluation of porous pavements used in Oregon

Younger, Krey 08 November 1994 (has links)
Graduation date: 1995
358

An evaluation of the stated student outcomes of the Drug Abuse Resistance Education (DARE) program

Uibel, Barbara Marie 11 1900 (has links)
The purpose of this study was to evaluate the stated student outcomes of the Drug Abuse Resistance Education (D.A.R.E.) program including decreases in positive attitudes toward the use of abusable psychotropics and decreases in the self-reported use of the abusable psychotropics. A multivariate quasi-experimental (pre-test, post-test, post-test) design was used and data were collected measuring student demographics, reported drug use, and drug-related attitudes. Participants were 522 grade five and six students from 44 classrooms. Results indicated that the Drug Abuse Resistance Education program had little lasting effect on drug-related attitudes and reported drug use. The findings are stratified by evaluated risk of substance abuse to determine whether there was a differential effect of the Drug Abuse Resistance Education program on subgroups delineated by risk for abusable psychotropic use. Recommendations are made in relation to the findings of this study with regard to pedagogy, programming and possible factors that inform the decisions about abusable psychotropics among this population. Although these findings represent conditions and views at the time of data collection and reflected in the initial literature review, they remain relevant as the issues and motivations that inform the decisions that young people make with regard to the use of abusable psychotropics, as reflected in the second literature review, continues to be an area of significant concern. The matter of devising and implementing timely, effective programming to address the complex problem of abusable psychotropic use by young people remains a relevant issue. / Special Education
359

Suppression of sourness in binary and tertiary model mixture solutions

Savant, Lotika 30 May 2001 (has links)
Addition of acids to foods allows for enhanced food safety. Acids are the primary form of defense against microbial contamination in refrigerated foods, while use of acids in conjunction with heat or high hydrostatic pressure processing lowers energy usage resulting in cost reduction. However, addition of acids to food or beverage formulations often reduces palatability due to higher sourness and this has limited the food industry's ability to better utilize them as preservatives. This study was aimed at gaining a better understanding of sourness suppression and its underlying mechanisms so that such limitations might be ultimately overcome. This work was divided into three parts dealing with the suppression of the sourness of citric, lactic and malic acids, as perceived by a trained sensory panel in a) binary mixtures with sugars, b) binary mixtures with salts and c) tertiary mixtures. The results of the first part showed that suppression was not mediated by sugar molarity or weight, but was significantly influenced by its perceived sweetness intensity in most cases. Sucrose and fructose were more effective than glucose in suppressing acid sourness and the data supported a separate receptor site/mechanism for glucose. Suppression was thought to have both central and peripheral components. In binary acid-salt mixtures sodium acetate (NaAc) affected the most sourness reduction, along with the largest concurrent pH increase (above 4.4). Sodium chloride (NaCl) mixtures showed significant suppression without a pH increase. Sodium gluconate (NaGluc) mixtures showed moderate suppression with citric and malic acids with pH increases remaining below 4.4, but showed little effect on lactic acid sourness. Saltiness appeared to drive suppression only in the case of NaCl, while pH change was responsible for reduction of sourness with NaAc and NaGluc. The tertiary trials indicated that a two-component multiple masker was more effective when its components stimulated different (as opposed to similar) receptors/receptor mechanisms in the taste system, irrespective of taste quality. Furthermore, a two-component masker was more effective than each component alone, and both components of a two-component masker did not have to be effective individually for them to function together as an effective multiple masker. / Graduation date: 2002
360

Investigating comprehensive assessment plans in undergraduate communication studies programs

Weber, Andrea Celeste. January 2007 (has links)
Thesis (Ed. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains iv, 107 p. Includes abstract. Includes bibliographical references (p. 88-93).

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