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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

Perceptions of violence among high school students /

Sanner, Beth, January 2006 (has links) (PDF)
Thesis (M.S.)--Eastern Illinois University, 2006. / Includes bibliographical references (leaves 61-63).
92

Analysis of the methods used in the public high schools of Massachusetts for assigning and hiring officials for interscholastic football games

Mahoney, Richard D. January 1952 (has links)
Thesis (Ed.M.)--Boston University
93

Die departementshoof: Afrikaans as professionele en akademiese leier

Underhay, George Malherbe 14 August 2014 (has links)
M.Ed. (Educational Management) / The teaching profession currently finds itself in a period of rapid changes and progress. This is particularly applicable to the management style and ingenuity required of educational leaders. It will therefore be incumbent upon the Head of Department: Afrikaans to keep up with latest development in management to provide quality teaching and learning. If teachers are to reach their optimum potential as educators, the Head of Department: Afrikaans must display the highest standard of supportive leadership. Analysis of the leadership task of the Head of Department: Afrikaans indicates that the modern view on leadership focuses on the potential to be found in the members of the Afrikaans Department. If the Head of Department: Afrikaans identifies himself with this viewpoint and if he applies his acquired leadership skills to this end, he will succeed in influencing his staff members to the extent that this positive motivation becomes manifested in those staff members who manage to sustain a high level of dedication in their work situation without constant monitoring. It is also imperative for the Head of Department: Afrikaans to become aware of the most effective leadership principles in both theory and practice. The leader that strives to create an open work climate, will receive the benefits of total participation as well as improved interpersonal relationships between himself and his staff members in the department. Apart from the climate that needs to be open and easy, it is also important that the leader should consider the specific situation in which they interact as a work group as a determining factor in the choice, and practice, of leadership styles. The congruency leadership model of Nicholls proves exceptionally appropriate in this regard. Another responsibility of the Head of Department: Afrikaans will be to attain a high degree of functional efficiency within his department. In this regard it will also be necessary for him to be proficient in an appropriate leadership style. The Principal of the school needs to delegate some leadership responsibility to the Head of Department: Afrikaans to the extent that he will fulfill a supportive role. Formal, standardised supervision should make way for a more fluent, ennobling way of supervision. In the light of the aforegoing statement, the real value of clinical supervision as the primary leadership role of the DSA rests upon his ability to facilitate the professional development of staff members and to improve their teaching skills.
94

Effects of limiting access to diets with different composition on binge-like eating

Lee, Harrison Sunjoon 08 June 2020 (has links)
Binge Eating Disorder (BED) is a deadly, psychiatric condition which affects about 10 million people in the USA. It is characterized by discrete and recurrent binge eating episodes consisting of rapid consumption of excessive amounts of highly palatable, energy-dense food (e.g. rich in sugars and fats) within discrete periods of time. Our laboratory has been focusing on the understanding of the behavioral, metabolic, and neurobiological factors underlying BED, through the development of an animal model of binge-like eating. This model is based on a limited access schedule in which rats are exposed 1-hour/day to a high-sucrose diet (HSD) in operant conditioning self-administration boxes. However, the consummatory and metabolic outcomes of exposing rats to a high-fat diet (HFD) in the same procedure are unknown. The aim of this thesis was to test the consummatory and metabolic effects of 1-hour limited access to either a HSD or a HFD in an operant rat model of binge-like eating. For this purpose, female rats were subjects of the binge-like eating procedure by limiting access to a HSD, a HFD, or a standard Chow diet. Our results show that limiting access to either a HSD or a HFD promoted binge-like eating as compared to control Chow diet. HSD binge-like eating was based on a true increase in the amount of food consumed, that is, an increased eating rate. Such suggests increase in palatability and a decrease in the home-cage standard chow intake, likely due to a negative contrast effect. Conversely, binge-like eating of the high-fat diet resulted from passive energy consumption due to the high energy-density of the food. Also, HFD binge-like eating was accompanied by neither increased eating rate nor rejection of the home-cage chow. Moreover, while HSD rats consumed less energy than HFD rats, the former were more energy efficient and gained more body weight than the latter. These results provide information on how the quality of food can deeply influence the behavioral and metabolic outcomes of binge-like eating. / 2022-06-07T00:00:00Z
95

The healthy organisation: is it meaningful?

Oldenboom, Erna 21 August 2022 (has links) (PDF)
In the thesis we have defined what is understood as a high health organization, and this in comparison with what is commonly known as a high performance organization. While much research is undertaken around high performance organizations, little or no research is undertaken around high health organizations. The thesis attempts to find answers to what it takes to be or to become a high health organization, and how organizations could create such a place, or possibly better “space”. Indeed, a high health organization is not a place, a building, or on organizational structure; it is a state of mind, a purpose, a form of coherence. The work in this thesis is by definition multidisciplinary and systemic, rooted in three, for the purpose, complementary research areas. Workplace spirituality is slowly making its recognition in the management literature, though still too much as a discipline in itself. Ayurveda, the thousands of years old wisdom tradition around systemic health, living systems and purposefulness does get some attention in academic work, however mainly within its cultural roots (of India). Finally, systemic thinking, not really mainstream yet either, is a scientific discipline that did find its way in the sciences, but is much less popular and use in management studies. As argued, we think that in the intersection of workplace spirituality, Ayurveda and systemics, a real new concept of a high health organization is emerging. Key concepts identified in the introduction were consciousness and coherence, which they play an important role in the entire thesis. The prevailing management research is based on an ontology of materialism, while it is clear that workplace spirituality, Ayurveda and systemics do not necessarily fit such an ontology. We have commented on an ontology of non-materialism, based on complexity theory and in particular the understanding of complex adaptive systems. If we would like to explore the concept of a high health organization, an adequate ontology (and epistemology) is necessary. It is impossible to develop a non-materialistic concepts within a materialistic ontology. The consequence of this ontological choice for our research methods are multiple and innovative. Our research method goes beyond deterministic causality, and attempts to visualize entanglement. It can only be based on a much more systemic analysis than what we are used to, hence we use Artificial Neural Networks and Semantics as analytical tools. Based on the results of our field research, the high health organization in a nutshell has the following components: 1. A systemic, values-based vision is the lighthouse of the high health organization 2. Values, and in particular lived values, are the driver of the high health organization 3. Transparent, clear, respectful and non-violent communication is the binding factor 4. A knowledge and learning culture is the necessary condition for a healthy organization 5. Organisational consciousness in the organization is the sufficient condition
96

A technique for determining the operating capacity of secondary-school buildings /

Conrad, Marion James January 1952 (has links)
No description available.
97

High Frequency, High Efficiency Two-Stage Approach for Future Microprocessors

Ren, Yuancheng 27 April 2005 (has links)
It is perceived that Moore's Law will prevail at least for the next decade, with continuous advancements of processing technologies for very-large-scale integrated (VLSI) circuits. Nano technology is driving VLSI circuits in a path of greater transistor integration, faster clock frequency, and lower operation voltage. This has imposed a new challenge for delivering high- quality power to modern processors. Power management technology is critical for transferring the required high current in a highly efficient way, and accurately regulating the sub-1V voltage in very fast dynamic transient response conditions. Furthermore, the VRs are limited in a given area and the power density is important to save the precious real estate of the motherboard. Based on the power delivery path model, the analysis results show that as long as the bandwidth can reach around 350 kHz, the bulk capacitor of the VR can be completely eliminated, which means significant savings in cost and real estate. Analysis also indicates that 650kHz bandwidth can reduce the number of the decoupling capacitor from 230 to 50 for future microprocessor case. Beyond 650kHz, the reduction is not obvious any more due to the parasitic components along the power delivery path. Following the vision of high bandwidth, the VRs need to operate at much higher frequency than today's practice. Unfortunately, the multiphase buck converter cannot benefit from it due to the low efficiency at high switching frequency. The extreme duty is the bottleneck. The extreme duty cycle increases VR switching loss, reverse recovery loss, and conduction loss; therefore makes the 12V-input VR efficiency drop a good deal when compared with 5V-input VR efficiency. Two-stage approach is proposed in this dissertation to solve this issue. The analysis shows that the two-stage conversion has much better high frequency capability than the conventional single stage VRs. Based on today's commercial devices, 2-MHz is realized by the hardware and 350kHz bandwidth is achieved to eliminate the output bulk capacitors. Further improvement based on future devices and several proposed methods of reducing switching loss and body diode loss can push the switching frequency up to 4MHz while maintaining good efficiency. Such a high frequency makes the high bandwidth design (650kHz) feasible. Hence, the output capacitance can be significantly reduced to save cost and real estate. The two-stage concept is also effective in laptop computer and 48V DPS applications. It has been experimentally proved that two-stage VR is able to achieve higher switching frequency than single stage not only at full load condition but also at light load condition by the proposed ABVP and AFP concept based on two-stage configuration. These unique control strategies make the two-stage approach even more attractive. As the two-stage approach is applied to 48V DPS applications, such as telecommunication system and server systems, more efficient and higher power density power supply can be achieved while greatly cut down the cost. Therefore, after the two-stage approach is proposed, it has been widely adopted by the industry. In order to further reduce the output capacitance, the power architecture of computer needs to be modified. Based on two-stage approach, one possible solution is to move the second stage VR up to the OLGA board. Based on this structure, the parasitics can be dramatically reduced and the number of the cavity capacitor is reduced from 50 to 14. By reducing ESL of the capacitor, the output capacitance could be further reduced. After that and based on two-stage approach again, VR+LR structure is discussed, which provides the opportunity to reduce the output capacitance and integrate the power supply with CPU. The feasibility is studied in this dissertation from both power loss reduction and output capacitance reduction perspectives. Experimental results prove that LR can significantly reduce the voltage spike while minimizing the output capacitance. As a conclusion, the two-stage approach is a promising solution for powering future processors. It is widely effective in computer and communication systems. Far beyond that, it provides a feasible platform for new architectures to power the future microprocessors. / Ph. D.
98

High Frequency High-Efficiency Voltage Regulators for Future Microprocessors

Wei, Jia 27 September 2004 (has links)
Microprocessors in today's computers continue to get faster and more powerful. From the Intel 80X86 series to today's Pentium IV, CPUs have greatly improved in performance. Accordingly, their power consumption has increased dramatically [1][2]. An evolution began in power loss reduction when the high-performance Pentium processor was driven by a non-standard, less-than-5V power supply, instead of drawing its power from the 5V plane on the system board. In order to provide the power as quickly as possible, the voltage regulator (VR), a dedicated DC-DC converter, is placed in close proximity to power the processor. At first, VRs drew power from the 5V output of the silver box. As the power delivered through the VR increased so dramatically, it became no longer efficient to use the 5V bus. Then for desktop and workstation applications, the VR input voltage moved to the 12V output of the silver box. For laptop application, the VR input voltage range covers the battery voltage range and the adaptor voltage. In the meantime, microprocessors will run at very low voltage (sub 1V), and will consume up to 150A of current, and will have dynamics of about 400A/us. The current VR solution is the 12V-input multiphase interleaved buck converter. The switching frequency is around 300KHz. This approach has several limitations for the future. OSCON capacitor is one limitation due to its large ESR and ESL; the low switching frequency the second limitation and the large inductance is the third limitation. Analysis shows that the all-ceramic solution is a better solution than the OSCON solution when the VR switching frequency reaches 1MHz. However, the 12V-input multiphase buck converter suffers low efficiency at high switching frequency, which rules out a legitimate chance of the current VR topology benefiting from high switching frequency. The extreme duty cycle is the fundamental reason why the 12V-input multiphase buck converter is not suitable for future VRs. Employing the transformer concept can extend duty cycle, and therefore offer an opportunity to improve efficiency. The push-pull buck (PPB) converter is proposed as a solution. The efficiency is improved compared with the buck converter. Integrated magnetic techniques can be used to further improve the efficiency and simplify the implementation. The impact of transformer concept on transient response is analyzed. The PPB converter efficiency is still not satisfactory at 1MHz due to the switching loss. Switching loss being a barrier, soft switching is needed. The proposed soft-switched phase-shift buck (PSB) converter achieves soft switching for the top switches. Highly efficient power conversion is achieved at high switching frequency. The integrated magnetics makes the implementation concise and delivers good performance. Given that the PSB converter has good performance, the matrix-transformer phase-shift buck (MTPSB) converter is a simplified version of the four-phase PSB converter. The MTPSB converter trades off some performance with circuit complexity. This feature establishes itself as a very cost-effective solution for future VRs. The magnetic structure of the MTPSB converter is also very simple with the use of integrated magnetics. Mobile CPUs are used in laptop computers. They require very challenging power management. The challenges for a laptop VR are different from and greater than those for a desktop VR. A laptop VR needs to have high efficiency at both heavy load and light load, good transient response and small and light form-factor, and work well with the wide input voltage range. Future mobile CPUs demand very aggressive power. The current single-stage VR approach cannot provide a suitable solution for the future. The PSB converter has disadvantages in light-load efficiency and does not work well with wide input voltage range; therefore it is not a suitable solution for laptop VRs although it is still a suitable solution for desktop VRs. The two-stage approach solves the wide-input-voltage-range issue and improves efficiency at heavy load significantly. The intermediate bus voltage Vbus is a very important parameter impacting overall efficiency. There is not one optimal Vbus value for all load conditions. The heavier the load, the higher the optimal Vbus. Based on this fact, the ABVP control is proposed. Vbus is adaptively positioned according to the load current therefore optimal Vbus is achieved under most conditions. Experimental results verify the theoretical prediction. The ONP control is another control scheme proposed to improve the light-load efficiency. By selecting optimal number of phases based on mobile processor power states, the VR light-load efficiency is improved. Experimental results show the proof. The baby-buck concept is the third concept proposed to improve the very-light-load efficiency. By operating the baby-buck channel, the two-stage VR improves efficiency at very light load. The two-stage VR featuring the three proposed control schemes has much higher efficiency than the single-stage VR over a very wide load range; therefore the battery life is extended. The two-stage VR with the proposed control schemes is a good solution for future laptop VRs. The problem solving process in this work proves that good solutions in isolated converters can be modified to fit into the non-isolated application. Non-isolated converters and isolated converters are not two separated worlds. On the contrary, these two worlds have many things in common. Good concepts can be transplanted from one world to another with minor modification and many problems can be solved this way. Another proven point in this work is that sometimes the solution is a fundamental, such as the change of power delivery architecture. One should not be limited by what is available right now, and should think outside the box. Once a fundamental change is made, it is very beneficial to take full advantage of the change, as it provides new opportunities. / Ph. D.
99

Structural variations of feldspars at high pressure and high temperature

Kolbus, Lindsay Marie 05 June 2012 (has links)
Feldspar minerals are framework aluminosilicates that comprise approximately 60 percent of the Earth's crust. The elastic and thermodynamic properties of this important mineral group are needed for the interpretation of seismic wave velocities, for understanding cation partioning patterns and for the determination of phase boundaries and reactions involving feldspars in the Earth's crust. Until recently, no systematic approach has been applied to describe the structural behavior of feldspars as a function of pressure, temperature and composition. In this thesis, high-pressure and high-temperature X-ray diffraction data were collected for feldspars over a range of compositions which has led to the development a structural model that allows one to predict the structural evolution of feldspars at depth in the Earth's crust. Specifically, the equations of state have been determined for two plagioclase feldspars (An20 and An78) with different states of Al/Si ordering using single-crystal X-ray diffraction. This study has shown that the introduction of Al,Si disorder into plagioclase structures at constant composition softens the structure by 4(1)% for An0, 2.5(9)% for An20 and is essentially zero for An78 compositions. The effect of pressure on the structure of an ordered An20 was also determined up to 9.15 GPa using single-crystal X-ray diffraction and it was found that the dominant compression mechanism involves tilting of the AlO4 and SiO4 tetrahedra. Similarly, high-temperature single-crystal X-ray diffraction data collected from an ordered An26 plagioclase and powder X-ray diffraction collected on a suite of Na-rich plagioclases that were refined using the Rietveld method indicate that the major structural response to increased temperature involves tilting of the tetrahedra. Building on ideas originally proposed by Dr. Helen Megaw, the changes in the conformation of the tetrahedral framework of feldspars can be described in terms of four distinct tilt systems of rigid tetrahedra. This model demonstrates that the fundamental reason for the observed anisotropy and volume change of feldspars lies in the topology of the tetrahedral framework with the greatest contribution attributed to tilt systems 2 and 3. / Ph. D.
100

A Comparative Analysis of the Affiliated Courses Offered in Texas High Schools

Merrick, James Estes 08 1900 (has links)
The problem of this thesis is to determine what affiliated courses are most frequently offered to the students who attend the regular four year high schools in Texas, and to determine the relationship of the subjects taught to the scholastic population of the school.

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