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61.
62.
安徽省境内765km的长江干堤,由于均是在原来旧堤的基础上经逐年加高培厚的,修筑时均未按设计要求施工,致使堤身密实度不够,新老堤土之间结合不牢,在汛期高水位时易产生渗漏。20世纪70年代以来,安徽省高度重视对长江干堤渗漏隐患的处理,经过长期的实践,逐渐摸索出一套行之有效的除险加固方法,如锥探灌浆、灭杀白蚁、冲抓套吉、垂直铺塑防渗、粘土铺盖及压渗盖重等处理措施。使长江干堤的渗漏隐患得以基本消除,其具体作法可供类似工程借鉴。 相似文献
63.
The objective, strategy, and implementation details of a new undergraduate course, Internet-based Instrumentation and Control, are presented. The course has a companion laboratory that is supported by the National Science Foundation and industry. The combination is offered to senior-level undergraduate engineering students interested in sensing, instrumentation, control, and web programming that want to learn more about the integration of these technologies for solving real-world engineering problems. The course will also be offered to gifted high school seniors with similar interests and can serve as a vehicle to attract them to engineering disciplines. Preliminary assessment of the first offering of the course is encouraging and has shown that the course has achieved success in helping students understand concepts and master basic technologies for developing Internet-based automatic systems. 相似文献
64.
Joshua Vaughan Joel Fortgang William Singhose Jeffrey Donnell Thomas Kurfess 《Mechatronics》2008,18(4):179-186
It is commonly accepted that hands-on experiences increase both learning and enjoyment during coursework. Mechatronics projects provide both interesting and relevant hands-on experiences for a wide range of topics including design processes, basic mechatronics concepts, technical communication, and working in a group environment. ME2110: Creative Decisions and Design at Georgia Tech integrates mechatronics and technical communication into a sophomore level mechanical design class. This paper describes the course in detail, highlighting the course goals and layout, tools provided to the students, industry involvement, and the main challenges of administering such a course. 相似文献
65.
I. Aidos N. Kreb M. Boonman J.B. Luten R.M. Boom A. Van Der Padt 《Journal of food science》2003,68(2):581-586
ABSTRACT: A pilot plant used for upgrading herring byproducts into fish oil was analyzed on its operational efficiency and product quality. The temperature of the heat exchanger and the speeds of the pump and the 3-phase decanter were varied according to a 23 fractional factorial design. The initial amount of oxidation products present in the crude oil, its storage stability, and the yields from the different obtained products were determined. Multivariate data analysis of the advanced screening stage showed that T had neither influence on the quality nor on the yield in contrast to D and MP (P < 0.05). Process optimization results showed that the quality of the oil was influenced by an interaction effect between the speed of the MP and the D. Oils processed with the highest MP speed were the most stable during storage. 相似文献
66.
67.
Mark S. MACGREGOR Sue J. CARR 《Hemodialysis international. International Symposium on Home Hemodialysis》2007,11(Z2):S1-S4
Hemodialysis was a neglected aspect of nephrology in the UK. At the request of the Renal Association, the first UK Haemodialysis Masterclass was organized in 2007. The articles in this supplement arose from that meeting. Here, an overview of UK hemodialysis services and nephrology training is presented as background. Government‐funded dialysis should be provided to all UK citizens who require it. In 2005, there were 17,645 patients receiving hemodialysis, 5057 on peritoneal dialysis and 19,074 with kidney transplants, looked after by 359 nephrologists working in 73 National Health Service renal units. Renal replacement therapy incidence and prevalence remain comparatively low, at 108 and 694 per million population, respectively. Whether this represents inadequate provision or genuinely lower need remains unclear. The Renal Association sets clinical practice guidelines for dialysis, and audits performance via the UK Renal Registry. Postgraduate medical education is undergoing radical change in the UK. This is driven by the reduction in trainee doctors' working hours to 48 hr/week (mandated by the European Working Time Directive), and the governments' wish to reduce the duration of training, but also by a desire to formalize training, Our challenge is to continue to produce talented clinical nephrologists educated in breadth and depth, despite the reduced emphasis on clinical experience and omission of period of scientific research. The future for hemodialysis services in the UK is, however, promising with an expansion in the number of specialists and dialysis centers, and a growing interest in dialysis practice and research. 相似文献
68.
69.
研究了元素含量变化对8011铝合金防盗盖板综合性能的影响,在8011合金中改变Cu、Mn元素含量后可提高防盗盖板的强度,同时研究了烘烤处理后的强度变化问题。本文研究出了8011铝合金防盗盖板新的生产工艺制度。 相似文献
70.
A motivational model of rural students' intentions to persist in, versus drop out of, high school. 总被引:1,自引:0,他引:1
Using self-determination theory, the authors tested a motivational model to explain the conditions under which rural students formulate their intentions to persist in, versus drop out of, high school. The model argues that motivational variables underlie students' intentions to drop out and that students' motivation can be either supported in the classroom by autonomy-supportive teachers or frustrated by controlling teachers. LISREL analyses of questionnaire data from 483 rural high school students showed that the provision of autonomy support within classrooms predicted students' self-determined motivation and perceived competence. These motivational resources, in turn, predicted students' intentions to persist, versus drop out, and they did so even after controlling for the effect of achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献