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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.
71

Teacher perceptions of the effectiveness of the social studies teacher training program at Tabouk Teachers' College in Saudi Arabia

Alhwiti, Awad Hamad. January 2007 (has links)
Thesis (Ed. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 84 p. Vita. Includes abstract. Includes bibliographical references (p. 71-77).
72

Comparative analysis of teaching methods and learning styles in a high school computer spreadsheet unit

Davidson, Conda January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 72-81). Also available on the Internet.
73

Effective Knowledge Integration in Emergency Response Organizations

Gudi, Arvind 19 November 2008 (has links)
Natural and man-made disasters have gained attention at all levels of policy-making in recent years. Emergency management tasks are inherently complex and unpredictable, and often require coordination among multiple organizations across different levels and locations. Effectively managing various knowledge areas and the organizations involved has become a critical emergency management success factor. However, there is a general lack of understanding about how to describe and assess the complex nature of emergency management tasks and how knowledge integration can help managers improve emergency management task performance. The purpose of this exploratory research was first, to understand how emergency management operations are impacted by tasks that are complex and inter-organizational and second, to investigate how knowledge integration as a particular knowledge management strategy can improve the efficiency and effectiveness of the emergency tasks. Three types of specific knowledge were considered: context-specific, technology-specific, and context-and-technology-specific. The research setting was the Miami-Dade Emergency Operations Center (EOC) and the study was based on the survey responses from the participants in past EOC activations related to their emergency tasks and knowledge areas. The data included task attributes related to complexity, knowledge area, knowledge integration, specificity of knowledge, and task performance. The data was analyzed using multiple linear regressions and path analyses, to (1) examine the relationships between task complexity, knowledge integration, and performance, (2) the moderating effects of each type of specific knowledge on the relationship between task complexity and performance, and (3) the mediating role of knowledge integration. As per theory-based propositions, the results indicated that overall component complexity and interactive complexity tend to have a negative effect on task performance. But surprisingly, procedural rigidity tended to have a positive effect on performance in emergency management tasks. Also as per our expectation, knowledge integration had a positive relationship with task performance. Interestingly, the moderating effects of each type of specific knowledge on the relationship between task complexity and performance were varied and the extent of mediation of knowledge integration depended on the dimension of task complexity.
74

Can Headstart Programs Truly be Effective? Genetic Assessment of Cyclura Collei, The Headstarted Jamaican Iguana

Rasberry, Armed Baba 09 May 2015 (has links)
Headstarting is one of the more recent practices being used to maintain endangered populations in the wild. A headstart program was developed for the Jamaican iguana, Cyclura collei, in 1991 after its rediscovery in 1990. This current study tests the hypothesis that this population is experiencing a reduction in effective population size in spite of an increasing census population size due to the small number of nests available in the early years of the headstart program. A total of 875 individuals collected from 1991 to 2011 were genotyped at twelve variable microsatellite loci. Results from this study indicate a slight but significant decline in genetic variation (3% loss), and a modest proportional reduction in effective population size (0.075), since the initiation of the program. However, it is important to note these data also suggests that effective population size of this population is stabilizing.
75

A Case Study To Identify How Shared Decision Making and Collaboration between General and Exceptional Education Teachers Impact Effective and Ineffective Inclusion Practices

Strong, Faith Renee 10 August 2018 (has links)
Sergiovanni (1994) believed that the rationale for shared decision making is that those who are closest to students are best equipped to make educational decisions to improve instructional programs. Liontos (1994) believed that change is most likely to be effective and lasting when those who implement it feel a sense of ownership and responsibility for the process. Building level administrators along with general and exceptional education teachers play a vital role in making educational practices a reality in schools (Kilgore, 2011). The administrator must have adequate knowledge of what the practices entail and how to mobilize staff so these educational practices are implemented effectively. In order to embrace the philosophy of inclusion, teachers must eliminate the focus on labels of students and make students with disabilities and support needs the determining factors in the provision of services and placement settings. This requires the school staff to shift paradigms when determining how best to meet the needs of students with disabilities. The overall purpose of this study was to determine whether or not general and exceptional education teachers working together had an impact on the inclusion process. These two groups of teachers collaborated to address challenges that students meet in the general educational setting. Their goal was to provide the best possible learning experience for students with disabilities in the least restrictive environment. While this study only took into account the challenges and successes of one school, in one school district, it is a glimpse of what other teachers, general and exceptional education are facing in inclusive settings. Results of the study showed that collaboration between general and exceptional education teachers clearly resulted in greater teacher efficacy. These teachers believed that they could make a positive difference. Teachers who exhibited this confidence were more likely to engage in collaboration. Some of the general education teachers who had the strongest desire for collaboration and worked closely with an exceptional education teacher exhibited a number of positive traits that led to more effective inclusion instruction. With this in mind, it is important for educational leaders to do all that they can to provide professional training and development to offer ideas and instances of collaboration to help the students with disabilities and teachers involved in educating them.
76

The Use of Compression Precracking Constant Amplitude (CPCA) Test Method to Obtain Near-Threshold Fatigue Crack Growth Behavior In AA7075-T7351

McKnight, Dustin Henry 10 December 2005 (has links)
Traditionally, pre-cracking has been performed under tension-tension loading, followed by a load reduction scheme to obtain fatigue crack growth rate data in the near threshold regime. These data have been shown to exhibit load history effects due to remote crack closure. An alternative test method has been developed to minimize these load history effects. This test procedure uses compression pre-cracking to initiate a crack, followed by constant amplitude loading to grow the crack to failure. Compression-compression (C-C) loading as a means of forming a starter crack for fatigue crack growth is a relatively new concept. Cracks grown under C-C loading emanate from the notch tip due to a tensile residual stress field formed during the unloading cycle. The subsequent constant amplitude steady-state crack growth is free of load history effects, after crack growth beyond several compressive plastic zone sizes, and therefore will give a better steady-state representation of the near-threshold regime. A more in-depth examination at this phenomenon is performed herein.
77

Leadership and School Success: The Practices and Behaviors of Principals in Successful At-risk Schools

Powell, Susan T. 08 December 2004 (has links)
Students in many at-risk schools are not achieving at the same academic levels as their counterparts in middle-class schools. Many live in poverty, lack background experiences that would help them be successful, have parents who have not completed high school and may not speak English as their first language. The challenge for educators is how to ensure these students are successful despite these obstacles. This is even more critical today due to the rigid standards set by both state and federal legislation with the advent of the Standard of Learning tests in Virginia and the federal No Child Left Behind legislation. Students not meeting these standards will not be eligible to graduate from high school, a prerequisite for social and economic success in our society. A review of the literature indicates that the behaviors and practices of the principal influence and contribute to the success of students and leads to the thesis of this study: Effective leadership contributes to school success. Two key questions are asked: "What are the leadership behaviors and practices of principals in highly successful school with high concentrations of at-risk students?" and "How do principals in these schools influence the learning outcomes to close the achievement gap?" This study answers these questions by examining the behaviors and practices of principals in successful at-risk schools with a study of one successful at-risk school supported by a survey of the teachers in that school and two other successful at-risk schools. The findings led to some of the following conclusions: the vision of the principal is paramount for school success; the culture of the school must be as nurturing to teachers as the students; the teaching of the curriculum is foremost; the principal protects time for teaching and provides programs to address individual students' differences; the culture must embrace families as it does teachers and students; the principal is sometimes a "benign dictator" who makes decisions without the consideration of the teachers, and the primary job of the principal is instructional leader. Some of the recommendations propose that principals in at-risk schools know and articulate a vision for their schools success; create a warm and nurturing environment for all stakeholders; know the curriculum and recognize effective classroom instruction; provide programs that address individual students' needs and time on task for learning; understand when they must be the "benign dictator" instead of a collaborative leader; and use effective managerial skills in order to perform the primary job of principal: instructional leader. / Ph. D.
78

Thermoelastic Properties of Particle Reinforced Composites at the Micro and Macro Scales

Gudlur, Pradeep 14 January 2010 (has links)
Particle reinforced composites are widely used in tires, heat exchangers, thermal barrier coatings and many other applications, as they have good strength to weight ratio, excellent thermal insulation, ease of manufacturing and flexibility in design. During their service life, these composites are often subjected to harsh environments, which can degrade the thermo-mechanical properties of the constituents in the composites, affecting performance and lifetime of the composites. This study investigates performance of particle reinforced composites subjected to coupled heat conduction and thermo-elastic deformation at the macro and micro levels. A micromechanical model is used to determine the effective thermal and mechanical properties of the homogenized composite by incorporating microscopic characteristics of the composites. The constituent?s thermal conductivities of the composite are assumed to be functions of temperature and the elastic moduli to be functions of temperature and stress fields. The effective properties obtained from the micromechanical model represent average (macroscopic) properties. The effective heat conduction and thermo-elastic responses in the homogenized composites are compared with the responses of the composite with particles randomly distributed in the matrix (heterogeneous materials) which represent microscopic responses. For this purpose, two sets of finite element (FE) models are generated for composites with particle volume contents 12.5, 25, and 50%. The first FE model represents a homogenized composite panel and the effective responses from the micromechanical model are used as input for the material properties. The second FE model mimics composite microstructure with discontinuous particles randomly dispersed in a homogeneous matrix. Parametric studies on effects of conductivity ratio between particle and matrix, degree of nonlinearity, and volume fraction on the temperature distribution and steady state times have been studied. For lower volume fractions the temperature profiles of homogenized and heterogeneous composite models are in good agreement with each other. But for higher volume fractions, the detailed model showed a wavy profile whereas the effective model showed no signs of it. When the nonlinearity in thermal conductivity of the particle and matrix constituents is increased, the steady state time significantly deviates from the ones with constant constituent properties. When the volume fraction of particles in the composite increases, the steady state is reached in less time, since the thermal conductivity of particles are taken larger than that of the matrix. Effects of coefficient of thermal expansion (CTE) ratio of particle and matrix, temperature change, and volume fraction on the discontinuity of stress and strain fields at the interphase of matrix and particle have been studied. The stresses developed were more for higher CTE ratios and the magnitude of discontinuity also follows the same trend. As the volume fraction increases, the stresses developed and the magnitude of discontinuity also increase. Finally, sequentially coupled heat conduction and deformation analyses are performed on thermal barrier coating (TBC) systems to demonstrate the applicability of the micromechanical model in predicting overall thermo-elastic responses of the TBC.
79

Thermoelastic Properties of Particle Reinforced Composites at the Micro and Macro Scales

Gudlur, Pradeep 14 January 2010 (has links)
Particle reinforced composites are widely used in tires, heat exchangers, thermal barrier coatings and many other applications, as they have good strength to weight ratio, excellent thermal insulation, ease of manufacturing and flexibility in design. During their service life, these composites are often subjected to harsh environments, which can degrade the thermo-mechanical properties of the constituents in the composites, affecting performance and lifetime of the composites. This study investigates performance of particle reinforced composites subjected to coupled heat conduction and thermo-elastic deformation at the macro and micro levels. A micromechanical model is used to determine the effective thermal and mechanical properties of the homogenized composite by incorporating microscopic characteristics of the composites. The constituent?s thermal conductivities of the composite are assumed to be functions of temperature and the elastic moduli to be functions of temperature and stress fields. The effective properties obtained from the micromechanical model represent average (macroscopic) properties. The effective heat conduction and thermo-elastic responses in the homogenized composites are compared with the responses of the composite with particles randomly distributed in the matrix (heterogeneous materials) which represent microscopic responses. For this purpose, two sets of finite element (FE) models are generated for composites with particle volume contents 12.5, 25, and 50%. The first FE model represents a homogenized composite panel and the effective responses from the micromechanical model are used as input for the material properties. The second FE model mimics composite microstructure with discontinuous particles randomly dispersed in a homogeneous matrix. Parametric studies on effects of conductivity ratio between particle and matrix, degree of nonlinearity, and volume fraction on the temperature distribution and steady state times have been studied. For lower volume fractions the temperature profiles of homogenized and heterogeneous composite models are in good agreement with each other. But for higher volume fractions, the detailed model showed a wavy profile whereas the effective model showed no signs of it. When the nonlinearity in thermal conductivity of the particle and matrix constituents is increased, the steady state time significantly deviates from the ones with constant constituent properties. When the volume fraction of particles in the composite increases, the steady state is reached in less time, since the thermal conductivity of particles are taken larger than that of the matrix. Effects of coefficient of thermal expansion (CTE) ratio of particle and matrix, temperature change, and volume fraction on the discontinuity of stress and strain fields at the interphase of matrix and particle have been studied. The stresses developed were more for higher CTE ratios and the magnitude of discontinuity also follows the same trend. As the volume fraction increases, the stresses developed and the magnitude of discontinuity also increase. Finally, sequentially coupled heat conduction and deformation analyses are performed on thermal barrier coating (TBC) systems to demonstrate the applicability of the micromechanical model in predicting overall thermo-elastic responses of the TBC.
80

Heterogeneous mixtures for synthetic antenna substrates

Njoku, Chinwe Christiana January 2013 (has links)
Heterogeneous mixtures have the potential to be used as synthetic substrates for antenna applications giving the antenna designer new degrees of freedom to control the permittivity and/or permeability in three dimensions such as by a smooth variation of the density of the inclusions, the height of the substrate and the manufacture the whole antenna system in one process. Electromagnetic, fabrication, environmental, time and cost advantages are potential especially when combined with nano-fabrication techniques. Readily available and cheap materials such as Polyethylene and Copper can be used in creating these heterogeneous materials. These advantages have been further explained in this thesis. In this thesis, the research presented is on canonical, numerical and measurement analysis on heterogeneous mixtures that can be used as substrates for microwave applications. It is hypothesised that heterogeneous mixtures can be used to design bespoke artificial dielectric substrates for say, patch antennas. The canonical equations from published literature describing the effective permittivity, ε_eff and effective permeability, μ_eff of heterogeneous mixtures have been extensively examined and compared with each other. Several simulations of homogenous and heterogeneous media have been carried out and an extraction/inversion algorithm applied to find their ε_eff and μ_eff. Parametric studies have been presented to show how the different variables of the equations and the simulations affect the accuracy of the results. The extracted results from the inversion process showed very good agreement with the known values of the homogenous media. Numerically and canonically computed values of ε_eff and μ_eff of various heterogeneous media were shown to have good agreement. The fabrication techniques used in creating the samples used in this research were examined, along with the different measurement methods used in characterising their electromagnetic properties via simulations and measurements. The challenges faced with these measurement methods were explained including the possible sources of error. Patch antennas were used to investigate how the performance of an antenna may be affected by heterogeneous media with metallic inclusions. The performance of the patch antenna was not inhibited by the presence of the metallic inclusions in close proximity. The patch measurement was also used as a measurement technique in determining the ε_eff of the samples.

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