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31.
32.
Weiwei Yang Jiejunyi Liang Jue Yang Paul D. Walker Nong Zhang 《Journal of The Franklin Institute》2021,358(2):1214-1239
An hybrid uninterrupted multi-speed transmission (HUMST), based on the integration of a planetary gear set and a 3-speed automatic manual transmission (3-AMT), is developed to satisfy the specific performance indexes of mining trucks. The power-split device can alleviate and eliminate the inherent torque interruption of the 3-AMT during gear shift by implementing the designed cooperative shift control strategy which is optimized by quadratic performance index. In order to achieve fast torque coordination while guaranteeing the driving comfort performance, the torque profiles of the power split device and the traction motor are optimized by Linear-quadratic regulator (LQR) algorithm. Dynamic programming (DP) is implemented as a benchmark to demonstrate the maximum fuel efficiency of the proposed HUMST. Because of the high computational cost of optimal control strategies such as DP, an improved real-time control strategy (IRTCS) using modified Gaussian distribution function is proposed to significantly reduce the computing load. As efficiency-oriented energy control strategy would result in frequent gear shifts, to achieve a desirable tradeoff between the overall efficiency and the shift stability, multi-objective genetic algorithm (MGA) is integrated to optimize the overall performance. The detail mathematical and dynamic model shows that the proposed shifting strategy with LQR can effectively suppress shift jerk, and the proposed IRTCS with MGA can reduce shift frequency by 70.78% to improve the drivability, only sacrificing 4.86% of overall efficiency compared to that of DP. 相似文献
33.
Andrea C. Walker Rachelle Gewecke Illene N. Cupit Jeffrey T. Fox 《Journal of College Counseling》2014,17(2):131-149
This phenomenological study, based on ecological systems theory, examined the college student bereavement experience in a Christian university. Undergraduate students (N = 127) from a small Christian university provided answers to open‐ended questions about their experiences regarding college following a death loss. Results indicate that students are generally successful in adapting to bereavement and prefer an environment open to discussing death and asking difficult religious questions. Implications for counselors are provided. 相似文献
34.
35.
Patricia A Hageman Carol H Pullen Susan Noble Walker Linda S Boeckner 《Cardiopulmonary Physical Therapy Journal》2010,21(3):27-34
Purpose: This study examined whether rural women, who had a high prevalence of prehypertension and hypertension upon enrollment in a wellness program, would also have a high prevalence of other cardiovascular disease risk factors such as low fitness and/or dyslipidemia. Methods: Data were analyzed from 225 rural women, ages 50-69, enrolled in a healthy eating and activity clinical trial. Cardiovascular health histories, fitness measures, blood pressure, and fasting blood serum samples were collected following standardized protocols at rural research offices. Chi-square and MANOVA were performed to examine differences in health characteristics, lipids, and fitness across blood pressure categories. Results: Fitness indicators of estimated VO2max, 1-mile walk time, and resting heart rate differed between the blood pressure groups, with those in the prehypertensive and hypertensive groups having less desirable profiles than those in the normotensive group. Triglyceride levels of 150 mg/dL or greater, were observed in 36%, 32%, and 16.7% of women who had hypertensive, prehypertensive, and normal blood pressures, respectively. Conclusions: The need for routine blood pressure screenings by practitioners is reinforced by finding that rural women screened via PAR-Q and/or physician clearance had a high prevalence of prehypertensive and hypertensive blood pressures, in addition to low fitness and nonoptimal triglycerides. Practitioners need to provide counselling based on results and refer to other providers as appropriate.Key Words: blood pressure, lipids, fitness, rural women 相似文献
36.
Case Study,Case Records and Multimedia 总被引:1,自引:0,他引:1
Rob Walker 《Cambridge Journal of Education》2002,32(1):109-127
37.
The purpose of this paper is to understand historically and contextually the well-being and agency of selected female teachers in Turkey. The paper develops a justice model based on the capability approach to build on the relation between freedom and equality, and to take gender and cultural diversity as a key element. The research draws on results from in-depth biographical narratives of 15 participants from west Turkey, examining the real freedoms and opportunities of three different generations of female teachers through constructing a gendered look into women's lives. The study begins by developing a framework linking women's opportunities and freedoms drawing its normative compass from Martha Nussbaum's capabilities approach. It explores how female teachers’ well-being can be understood in relation to key capabilities that individuals, communities and society have reason to value and how these capabilities and functionings can be expanded or constrained. The paper argues for the significance of thinking about capabilities in the professional lives of teachers who work for social change. Through a historical and generational sequence, it captures the egalitarian aspects of the capability approach, and strengthens its emphasis on freedoms of women. The findings of this enquiry indicate that there are persistent economic, cultural, ethnical, structural and gendered inequalities in women's lives, but that women also have agency to bring changes in their lives and through their teaching. 相似文献
38.
This study reports on a very successful collaboration between teacher education courses in Manchester and Amsterdam and the Van Gogh Museum in Amsterdam. The central aim of the initiative was to promote and sustain partnerships between Higher Education (HE) institutions, public galleries and schools with a view to developing, delivering and sharing good practice in art and design within a European context. 相似文献
39.
In this paper we review arguments that have been well rehearsed in the economic literature in the past twenty years and which are relevant to the present debate over student loans and the funding of the higher education sector.
The body of the paper assesses four finding proposals: (1) The Government's mortgage-type loan scheme, (2) The Barr, National Insurance repayment scheme, (3) The Graduate Tax and (4) A Loan scheme based on the individual higher education institution.
Each proposal is assessed in terms of its efficiency impact in six dimensions, (i) set up costs and flexibility, (ii) administrative costs (iii) incentives (iv) information (v) the balance of public and private involvement, and (vi) equity.
We conclude that, overall, we would not recommend any of the alternatives as unambiguously superior on all counts. Insofar as a radical approach is to be implemented we argue that a scheme based on the individual higher education institution, with repayment via the National Insurance system, is probably the best option. 相似文献
The body of the paper assesses four finding proposals: (1) The Government's mortgage-type loan scheme, (2) The Barr, National Insurance repayment scheme, (3) The Graduate Tax and (4) A Loan scheme based on the individual higher education institution.
Each proposal is assessed in terms of its efficiency impact in six dimensions, (i) set up costs and flexibility, (ii) administrative costs (iii) incentives (iv) information (v) the balance of public and private involvement, and (vi) equity.
We conclude that, overall, we would not recommend any of the alternatives as unambiguously superior on all counts. Insofar as a radical approach is to be implemented we argue that a scheme based on the individual higher education institution, with repayment via the National Insurance system, is probably the best option. 相似文献
40.