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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.
91

A Meta-Study of Journal of College Counseling (JCC) Author and Article Publication Characteristics From 1998 to 2009

Byrd, Rebekah, Crockett, Stephanie A., Erford, Bradley T. 01 July 2012 (has links)
Patterns of articles accepted for publication in the Journal of College Counseling from the past 12 years were reviewed in this metastudy. Results were described and statistically analyzed to identify trends over time in characteristics of authors, including sex, institutional classifications, employment setting, and domicile, and characteristics of articles, including article type, research design, sample size, types of participants, and statistical procedures.
92

Prevalence, distribution and characteristics of youth not enrolled in school : evidence from the Community Survey 2007, South Africa.

Monyela, Makgongoana Henry 15 March 2012 (has links)
The Education for All Movement (EFA) premises its commitment on the belief that quality education for all youth will ensure that they have equal access to skills and knowledge that will assist them in getting into gainful employment and enable them to participate fully in their societies. The importance and benefits of providing access to education and lifelong learning opportunities to youth has been acknowledged by a majority of world countries. These countries believe that quality education to youth means the ability to survive, to live and work in dignity, to participate fully in development, improve quality of their lives, to make informed decisions, and continuous learning – requirements for citizens of the 21st century. However, EFA mid-term report shows that as much as 42% of the world’s secondary school going-age youth were not enrolled in 2006, the majority of these youth are found in sub-Saharan Africa. There are a few empirical studies on the extent of school non-attendance and the profile of these youth not enrolled in an educational institution in the region. The study makes use of the Statistics South Africa dataset, Community Survey 2007, to determine the prevalence of school non-enrolment in South Africa among the 16 to 18 year olds. Second, the study attempts to establish the characteristics of the youth not enrolled in an education institution. To this end, the study analyzed the extent of non-enrolment prevalence, vi and the geographic distribution of the problem. In order to determine the geographic distribution of the problem, I first look at the size of school non-enrolment problem, nationally. I then analyse provincial, district and local patterns of school non-enrolment. Lastly, I analyse the data for identifiable individual and family factors that could be associated with the youth not currently enrolled in an educational institution. My analysis shows that the extent of youth between 16 and 18 years not enrolled in school is 16.6%, confirming recent government reports on prevalence among this age cohort. The study reveals physiographic and sub-population characteristics associated with non-enrolment in school. Disability, lack of access to social security grants, the low education level of a parent, or head of household that is not a parent are factors found to be related with low school participation by youth from those households. The study recommends a deeper investigation on the impact that the physiographic characteristics have on patterns of school enrolment.
93

Static and Dynamic Characterization of Silicon Carbide and Gallium Nitride Power Semiconductors

Romero, Amy Marie 26 March 2018 (has links)
Wide-bandgap semiconductors have made and are continuing to make a major impact on the power electronics world. The most common commercially available wide-bandgap semiconductors for power electronics applications are SiC and GaN devices. This paper focuses on the newest devices emerging that are made with these wide-bandgap materials. The static and dynamic characterization of six different SiC MOSFETs from different manufacturers are presented. The static characterization consists of the output characteristics, transfer characteristics and device capacitances. High temperature (up to 150 °C) static characterization provides an insight into the dependence of threshold voltage and on-state resistance on temperature. The dynamic characterizations of the devices are conducted by performing the double-pulse test. The switching characteristics are also tested at high temperature, with the presented results putting an emphasis on one of the devices. A comparison of the key characterization results summarizes the performance of the different devices. The characterization of one of the SiC MOSFETs is then continued with a short-circuit failure mode operation test. The device is subjected to non-destructive and destructive pulses to see how the device behaves. The non-destructive tests include a look at the performance under different external gate resistances and drain-source voltages. It is found that as the external gate resistance is increased, the waveforms get noisier. Also, as the drain-source voltage is increased, the maximum short-circuit current level rises. The destructive tests find the amount of time that the device is able to withstand short-circuit operation. At room temperature the device is able to withstand 4.5 μs whereas at 100 °C, the device is able to withstand 4.2 μs. It is found that despite the different conditions that the device is tested at for destructive tests, the energy that they can withstand is similar. This paper also presents the static and dynamic characterization of a 600 V, 2A, normallyoff, vertical gallium-nitride (GaN) transistor. A description of the fabrication process and the setup used to test the device are presented. The fabricated vertical GaN transistor has a threshold voltage of 3.3 V, a breakdown voltage of 600 V, an on-resistance of 880 mΩ, switching speeds up to 97 V/ns, and turn-on and turn-off switching losses of 8.12 µJ and 3.04 µJ, respectively, demonstrating the great potential of this device / MS / A key part in a power electronics circuit is the switch component. Currently, the devices usually used as the switch are made from silicon. As the performance limits of silicon are reached though, wide-bandgap semiconductors are proving to be a promising alternative to silicon semiconductors. These wide-bandgap switches will allow for higher powers, higher efficiency and higher temperature operation. The technology is still novel though and so new devices are still being developed. This paper focuses on showing the performance of the newest devices emerging that are made with these wide-bandgap materials. To demonstrate the performance potential of a switching device, the non-switching and switching behavior need to be tested. These tests are described and the results are shown for both Silicon Carbide (SiC) and Gallium Nitride (GaN) semiconductors which are the most common wide bandgap semiconductors. The failure mode operation of one of the SiC devices is also tested. A common failure in power electronics is a short circuit failure where the switch is turned on for a long amount of time and kept on for too long, eventually leading to the device breaking destructively. To understand the limits and capabilities of these devices in a short circuit failure, non-destructive and destructive tests are explained and demonstrated.
94

Notes on Dendrochronologies at the Arnold Arboretum

Schulman, Edmund 04 1900 (has links)
No description available.
95

Adjustment to amputation : identifying the contribution of family environment, coping style, functional ability and satisfaction with life variables to adjustment following unilateral below-knee amputation in adults

Harbridge, Jenny January 1998 (has links)
No description available.
96

Dehydration of potato cubes using puffing as an intermediate step

Varnalis, Angelos January 2000 (has links)
No description available.
97

Offence location and offender locale : community vs travelled offenders; an analysis of the spatial distribution of crime

Cox, Malcolm Richard January 2000 (has links)
No description available.
98

Growth series of certain groups

Gill, C. P. January 1995 (has links)
No description available.
99

An Analysis of Selected Characteristics of Persons Twenty-Five and Older Seeking Teacher Certification

Brooks, Robert Lee 06 1900 (has links)
The purposes of this study were (1) to describe the persons twenty-five and older entering the teacher education program and seeking certification, and (2) to compare the persons twenty-five and older with a "typical" group of persons under twenty-five with respect to (a) ability, as measured by the Cooperative School and College Ability Test, (b) factors for entering teaching, as measured by "Factors Influencing the Decision to Become a Teacher," (c) attitudes held toward teaching, as measured by the Kerlinger Education Attitude Scale, (d) professional aspirations, and (e) role expectations, as measured by the Teacher Practices. Questionnaire.
100

Serological Characterization of Members of the Genus Streptomyces

Taylor, Gerald Roger 08 1900 (has links)
This investigation involved isolation and characterization of specific antigenic materials from known species of Streptomyces. The resulting antigens were then used to establish serological relationships between a number of different species. These groupings were, in turn, compared with similar studies recently established by the ISP, in which other taxonomic criteria were used. By these means, the serological characteristics of the Streptomyces were evaluated for their potential utility as added taxonomic tools in the establishment of species designations within this group.

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