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1.
Calvyn Potgieter 《International Journal of Technology and Design Education》2004,14(3):205-218
In this article the impact of technology education, as a new learning area (subject) in the curriculum, on in-service teacher
education in South Africa is described in order to ascertain the extent of the impact. The research on which this article
is based draws on a variety of experiences and observations in the field at grassroots level (in particular an outreach project
in rural communities). The envisaged impact of technology education on South African schools, communities, teacher educators
and teachers, the range of in-service teacher education that is required, and the impacts in urban and rural areas are discussed.
Finally a number of concluding remarks are made about the extent of the impact of the inclusion of technology education in
the new National Curriculum Statement and whether the situation has changed since the implementation of a pilot technology
education project in 1998.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
Rolf Biehler 《Revue internationale de statistique》1997,65(2):167-189
The community of statisticians and statistics educators should take responsibility for the evaluation and improvement of software quality from the perspective of education. The paper will develop a perspective, an ideal system of requirements to critically evaluate existing software and to produce future software more adequate both for learning and doing statistics in introductory courses. Different kinds of tools and microworlds are needed. After discussing general requirements for such programs, a prototypical ideal software system will be presented in detail. It will be illustrated how such a system could be used to construct learning environments and to support elementary data analysis with exploratory working style. 相似文献
3.
精馏过程的节能,对于减少能源消耗,降低生产成本和保护环境具有十分重要的意义.在精馏过程中可以采用最适宜回流比操作和最佳进料状态,使用中间冷凝器和中间再沸器,高效精馏、热泵精馏.合理安排多组分物料分离流程,直接利用过程热量及开发应用高效换热器等措施.本文从最佳回流比R的选择、进料温度及进料状态的确定等方面,详细的分析了在精馏塔的设计过程中,如何实现设计的优化问题,以实现节能降耗. 相似文献
4.
5.
William Jack 《Economics of Transition》2002,10(3):619-635
As part of the reforms of their systems for financing and delivering health care, many transition economies, particularly in central and eastern Europe, have adopted national insurance funds that are institutionally separate from ministries of health. Most of these countries have also grappled with the problem of restructuring the delivery system, especially the need to reduce hospital capacity. Although improving the performance of medical care providers through a shift from passive budgeting to explicitly incentive mechanisms is important, why this change in financial relations between the government and providers could not be implemented simply by reforming the role of health ministries is not obvious. This paper presents an explicit rationale for the separation of powers between the regulator (the ministry of health) and the financing body (the insurance fund), based on the inability of a single agency to commit to closing hospitals. JEL classification: L51, P20, P35, I18. 相似文献
6.
Richard P. O’Neill Emily Bartholomew Fisher Benjamin F. Hobbs Ross Baldick 《Journal of Regulatory Economics》2008,34(3):220-250
The general design for the real-time electricity market presented in this paper optimizes and prices both real and reactive
power simultaneously in an AC setting, where all assets—generation, load and transmission—are allowed to bid and are financially
settled at the locational price times energy consumed or produced. The result is that transmission lines are compensated for
both capacity and admittance, providing incentives for efficient operation of transmission-related assets such as FACTS devices,
if price-taking behavior is assumed. Losses are incorporated into the design and become an operating cost for transmission.
The market design is shown to be revenue neutral and, under some assumptions, nonconfiscatory.
相似文献
7.
石璞 《中小企业管理与科技》2021,(8)
现阶段,随着社会经济的飞速发展,道路基础设施的建设速度逐渐加快。同时,随着各种各样桥梁病害问题的出现,对桥梁的承载能力造成了一定程度的影响。因此,及时防治桥梁病害有助于保障桥梁的安全性。论文结合某危桥改造项目,对桥梁的病害展开研讨,对病害的产生原因进行分析,并提供实用性的桥梁设计应对方法,以保证桥梁的耐久性与安全性。 相似文献
8.
We present general results for finding or boundingt
maxB
, the maximum number of arbitrary whole blocks of observations which can be removed from a block design, and still leave all of the elementary treatment contrasts estimable. The block sizes may be larger than the number of treatments. The results are applied to BBDs, reinforced BIBDs and BBDs, BTIBDs, and a series of variance balanced incomplete block designs with two block sizes. Also given for most of these designs, are results fort
max, the maximum number of arbitrary, scattered observations that can become unavailable, and still leave all of the elementary treatment contrasts estimable.The work was undertaken while Dr. Whittinghill was visiting Ohio State University, and supported by a grant from the Natural Sciences Division, Colby College, Waterville, Maine. 相似文献
9.
基于供应链的物流网络设计研究 总被引:1,自引:0,他引:1
比较分析了基于供应链的物流网络的设计特点,并提出了其设计原则与设计步骤. 相似文献
10.
生物电子等排原理在新药设计中的应用 总被引:4,自引:3,他引:4
探索生物电子等排原理在新药研究中应用的规律,推动新药研究的进展;通过查阅文献资料,阐述生物电子等排的定义及各类生物电子等排的特点、使用范围、典型事例;表明生物电子等排既有外层电子总数相等的原子或基因的替换,也有在体积、形状、构象、电子分布、脂水分配系数、pKa、化学反应性(包括代谢相似性)和氢键成键能力等重要参数上存在相似性的原子或基团的替换,是对已知药物的结构改造或结构修饰;所产生新化合物优于、近于或拮抗原来药物的作用,具有成功率高、风险小、投资少的特点,在新药研究中占有重要的地位。应用生物电子等排体进行新药设计,尤其适合我国制药工业现有的实际情况。 相似文献