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Statistics show that boys perform better in mathematics tests than girls. In order to make a refined assessment of the magnitude of gender differences in mathematics performance, a study was made of one thousand 16+ mathematics scripts to find the precise topics on which girls and boys differ significantly in performance. These concepts were found to be concerned with scale or ratio, spatial problems, space-time relationships and probability questions. Differences were found in performance between girls and boys at each ten-percentile level through the ability range. A longitudinal study also revealed differences in mathematics 'performance through the years of secondary education. There is no convincing evidence that the discrepancy can be accounted for by innate or genetic reasons. Intervention programmes have been found to improve the performance of girls in the weak areas of spatial awareness, proportionality and problem solving. In addition, a study was made of gender attitudes towards mathematics. Ten secondary schools were surveyed and the results revealed a marked decrease in the attitudes of third and fourth form girls. During these difficult adolescent years girls and boys are susceptible to strong internal and external pressures. Corresponding differences were also found across the ability range. These social pressures are concerned with teacher influence, social interaction, type of grouping, sex stereotyping, choices, teaching materials and careers advice.

<p> The effects of hydrostatic pressure on the superconducting transition temperatures of the simple metals aluminum, lead, mercury, tin and indium are investigated within the strong-coupling theory of superconductivity. The experimental variation of the transition temperature with volume change can be understood within a simple scaling model. Strong-coupling effects in the pressure dependence of superconductivity in lead and mercury are investigated.</p> <p> A formalism which includes effects of force constant disorder on superconductivity in a binary alloy of simple metals is established within pseudopotential theory.</p> / Thesis / Doctor of Philosophy (PhD)

The aim of this work was experimental study of features of high pressure influence onto tows of double-walled and single-walled carbon nanotubes. The structural transitions for carbon nanotubes subjected to external pressure with changes in the cross section of nanotubes were discovered by the method of molecular dynamics simulation and experimentation study. At higher pressures observed polymerization of carbon nanotubes. In the first section, an overview of current concepts about the structure of single-walled and multi-walled nanotubes and their electrical and mechanical properties are shown, as well as the methods of experimental study of the structure and properties are listed. Raman spectroscopy as one of the most sensitive and informative methods of research of carbon materials has been allocated in a separate paragraph. In the "EXPERIMENTAL" basic characteristics and principle of operation of two used in the work settings: press for creation high pressures and the displays system of the Raman confocal microscope WiTecAlpha AR + 300 have been described. The main conclusions:  Features on the curve of the electrical resistance dependence from the pressure of single-walled CNT correspond to known structural transitions in nanotubes related to changes in the cross section of nanotubes, found at 2 and 7 GPa. The pressure of 50 GPa is not critical for the investigated samples of single-walled nanotubes.  Similar features are found on the curve of the pressure resistance of double-walled CNT at 2 and 21 GPa. It was found that the resistance feature of about 24 GPa associated with the destruction of the external nanotubes structure of the double-walled nanotube. Thus, the assumption of a two-stage mechanism of destruction of double-wall CNT large diameter confirmed.  50 GPa pressure is critical for the investigated double -walled nanotubes. Based on the results, it can be concluded about the destruction of the double-walled CNT is happening at a pressure of 50 GPa. Those data allow us to judge the partial polymerization of double-walled CNT reaching the critical pressure of 50 GPa. / Целью работы являлось экспериментальное исследование особенностей воздействия высокого давления на жгуты двустенных и одностенных углеродных нанотрубок. Методами молекулярно-динамического моделирования и экспериментальным путем были обнаружены структурные переходы для углеродных нанотрубок подвергнутых внешнему давлению, связанные с изменением поперечного сечения нанотрубок. При более высоких давлениях наблюдалась полимеризация углеродных нанотрубок. В первом разделе приведен обзор современных представлений о структуре однослойных и многослойных нанотрубок, их электрических и механических свойствах, а также перечислены методы экспериментального исследования их структуры и свойств. В отдельный пункт была выделена спектроскопия комбинационного рассеяния света, как один из наиболее чувствительных и информативных методов исследования углеродных материалов. В разделе «МЕТОДИКА ЭКСПЕРИМЕНТА» были описаны основные характеристики и принцип работы двух использовавшихся в работе установок: пресса для создания высоких давлений и системы отображающей конфокальной микроскопии комбинационного рассеяния WiTecAlpha 300 AR+. Основные выводы работы:  Обнаружены особенности на кривой зависимости электросопротивления от давления одностенных УНТ при 2 и 7 ГПа, соответствующие известным структурным переходам в нанотрубках, и связанные с изменением сечения нанотрубок. Давление 50 ГПа не является критическим для исследованного образца одностенных УНТ.  Обнаружены аналогичные особенности на кривой зависимости сопротивления от давления двустенных УНТ при 2 и 21 ГПа. Было установлено, что особенность сопротивления около 24 ГПа связана с разрушением внешних нанотрубок в структуре двустенных УНТ. Таким образом, подтверждается предположение о двухступенчатом механизме разрушения двустенных УНТ большого диаметра.  Давление 50 ГПа является критическим для исследованных двустенных УНТ. Исходя из полученных результатов, можно сделать вывод о происходящем разрушении ДУНТ при давлении 50 ГПа. Те же данные позволяют судить о частичной полимеризации двустенных УНТ при достижении критического давления 50 ГПа.

<p>Due to the profound restructuring and erosion of social services and social programs, health and social services have been reorganized using business models that prize efficiency and cost saving rather than client centered service. Literature on social work practice in this context highlights the pressure on practitioners to standardize their work in order to manage higher workloads and to give primacy to employing organizations’ budgetary interests, rather than the interests of clients, patients and communities. Within this regulation of practice lies the regulation of time, yet in the literature there is relatively little explicit focus on the temporal control of social workers, or on how social workers manage and negotiate institutional time controls.</p> <p>This study sought to explore the intricacies of social workers’ negotiation of time pressures in health care settings. It aimed to examine how social workers perceived these time pressures, the strategies they employ to accommodate multiple demands on their time and how, in the end these time pressures influence social work practice.</p> <p>A small qualitative study was employed, using personal interviews to explore the experience of social workers employed in the health care industry. Participants were chosen according to their unique experiences within the health care system. An analysis of participants’ accounts suggests that, in the face of continuous and ever present time pressures, social work in health care is changing. As case loads increase and become more complex, social workers often find themselves negotiating time in order to manage the unavoidable collision between clock time and process time.</p> / Master of Social Work (MSW)

Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences. / Vita. / Includes bibliographical references. / Ph.D.

The presence of silt and clay particles has long been thought to affect the behavior of a sand under cyclic loading. Unfortunately, a review of studies published in the literature reveals that no clear conclusions can be drawn as to how altering fines content and plasticity actually affects the liquefaction resistance of a sand. In fact, the literature contains what appears to be contradictory evidence. There is a need to clarify the effects of fines content and plasticity on the liquefaction resistance of sandy soils, and to determine methods for accounting for these effects in engineering practice. In order to help answer these questions, a program of research in the form of a laboratory parametric study intended to clarify the effects which varying fines content and plasticity have upon the liquefaction resistance of sandy sands was undertaken. The program of research consisted of a large number of cyclic triaxial tests performed on two sands with varying quantities of plastic and non-plastic fines. The program of research also examined the applicability of plasticity based liquefaction criteria and the effects of fines content and plasticity on pore pressure generation. Lastly, a review of how the findings of this study may affect the manner in which simplified analyses are performed in engineering practice was made. The results of the study performed are used to clarify the effects of non-plastic fines content and resolve the majority of the inconsistencies in the literature. The effects of plastic fines content and fines plasticity are shown to be different than has been previously reported. The validity of plasticity based liquefaction criteria is established, the mechanism responsible for their validity is explained, and a new simplified criteria proposed. The effects of fines content and plasticity on pore pressure generation are discussed, and several recommendations are made for implementing the findings of this study into engineering practice. / Ph. D.

Yes / In this paper, we examine how and when chief executive offers’ (CEOs’) reputation enhances environmental innovation by considering quality management as a mediating mechanism of this relationship. In addition, we introduce stakeholder pressures (primary and secondary stakeholder pressures) as important contingencies of the relationship between CEOs’ reputation and quality management. Moreover, we test the moderating role of resource commitment on the quality management-environmental innovation relationship. We test our research model using data from a manufacturing industry sample of 217 firms from Ghana. We find that quality management mediates the relationship between reputation and environmental innovation. Moreover, the relationship between CEOs’ reputation and quality management is amplified when levels of both primary and secondary stakeholder pressures are greater. Finally, our findings show that the effect of quality management on environmental innovation is enhanced when resource commitment is greater. Implications for theory and practice are discussed.

This thesis explores the impacts of the Partnership for Incentive-Based Budgeting (PIBB) model at Virginia Tech (VT), a land-grant institution. By conducting a mixed-methods approach including semi-structured interviews, document analysis, and a review of political theory, this research examines the differences in perceptions of employees across employee classifications, academic area, and financial experience at VT on the PIBB model, unhealthy internal competition, communications, fiscal policy, and political influence. The PIBB model was adopted at VT as a strategic response to reduced state funding and aims to encourage budget management improvements and collaborative planning across the university. Findings indicate that while the PIBB model is designed to align financial incentives with the university's academic and operational goals, it may also foster unhealthy, internal competition among faculty, staff, and administrative units. This competition arises from the pressure to meet specific performance metrics linked to budgetary allocations, potentially leading to conflicts and misalignment with the university's broader educational objectives –underscoring the need for a balanced approach to budgeting that supports both financial sustainability and academic integrity. Complexities of implementing market-driven budgeting models within academic settings suggests that while such models can drive efficiency, they must be managed carefully to avoid undermining the core mission of educational institutions. This thesis contributes to ongoing discussions about the optimization of resource allocation in public higher education. / Master of Arts / This thesis looks at how the Partnership for Incentive-Based Budgeting (PIBB) model, implemented at Virginia Tech (VT), impacts various aspects of the university. Using a combination of interviews, document analysis, and a look into political theory, the research investigates how different employees at VT perceive the PIBB model, its effects on internal dynamics like competition, communication, financial policies, and political influences. The PIBB model was implemented as a result in the decline in state money going to VT and to help manage the budget better and collaboration across the university. This thesis research found that while the PIBB model tries to link money incentives with university goals, it also creates unhealthy competition among faculty, staff, and units within the university. This competition happens as everyone wants to meet certain goals to get more money, which can take away from the main goal of the university, which is education. The study shows that it is important to find a balance between the university's goals being at the forefront but also managing the money appropriately. It also shows that using budgeting methods based on business ideas in a public university is tricky and needs careful management to keep the university's values intact. Overall, this research adds to the conversation about how we can best use money in public colleges to make them better for everyone.

Metal on metal wear at high sliding speeds and high contact pressures results in the melting of one or both of the sliding solid bodies due to heat generated at the contact interface. Understanding the influence of sliding speeds, contact pressures and material properties on wear rates is important in developing predictive models for designing more efficient and effective engineering system components. Typical engineering applications subjected to these extreme conditions include ultrahigh speed machining, rocket sleds, large caliber cannon, and electromagnetic launchers. Sliding speeds on the order of 1,000 m/s and contact pressures in excess of 100 MPa are common in these applications and difficult to replicate in a laboratory environment. A unique wedge experiment using a minor caliber electromagnetic launcher has been developed and implemented to characterize wear deposition of a 6061-T6 aluminum sliding body on several different guider materials of varying mechanical and thermal properties at sliding speeds from 0 – 1,200 m/s and contact pressures from 100 – 225 MPa. Optical microscopy and 3D profilometry were used to characterize and quantify the slider wear. Three distinct wear regions, plasticity dominated, severe plastic deformation and melt lubrication were observed. Test results provided evidence that the aluminum slider contact interface was molten. Modeling of the experimental wear data showed a dependence on pressure and velocity and guider material properties, density and specific heat. A predictive wear model was developed for the melt lubrication region as a tool for designing components subjected to similar operating conditions.