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981.
多元智能理论为新课程的教学引领了一种新的教育理念,教育游戏则为这种新的教育理念的实施提供了有利条件.在信息技术环境下,教育游戏不仅能提高儿童的知识技能和智力智能,还有助于提高儿童的信息素养及综合素质.研究教育游戏与儿童多元智能开发具有重要意义.  相似文献   
982.
介绍一种砷化氢发生装置,采用蠕动泵自动进液,定时电路控制硼氢化钾或硼氢化钠的进液时间,并采用单向阀及螺纹口装置防止气体逸出,保证了砷化氢发生的均匀性和重复性。  相似文献   
983.
Publications on Adsorption Science and Technology   总被引:2,自引:0,他引:2  
S. Sircar 《Adsorption》2000,6(4):359-365
A key word search of Chemical Abstracts Registry and Derwent Patent Index on various topics of Adsorption Science and Technology between 1970–2000 reveals an immense volume of patents and publications in this area. A detailed breakdown of this search is provided.  相似文献   
984.
祝红艳 《电子测试》2014,(23):82-83
文章对网络环境下会计信息系统安全性研究,先对常用的安全防御技术进行了介绍,然后设计了企业内部的安全方案。  相似文献   
985.
Older adults are becoming an important market segment for all internet-based services, but few studies to date have considered older adults as online shoppers and users of entertainment media. Utilising the concept of life course, this article investigates the use of mobile technologies for online shopping and entertainment among consumers aged 55 to 74. The data were collected with a web-based survey completed by a panel of respondents representing Finnish television viewers (N = 322). The results reveal that consumers aged 55 to 74 use a smartphone or tablet to purchase products or services online as often as younger consumers. In contrast, listening to internet radio and watching videos or programmes online with a smartphone or tablet are most typical for younger male consumers. The results demonstrate that mobile-based online shopping is best predicted by age, higher education, and household type (children living at home), and use of entertainment media by age and gender.  相似文献   
986.
555时基电路在玩具控制应用中占有重要的地位。本文结合作者在高职院校毕业设计以及在中学开展科技发明、教具制作的经验,介绍了555时基电路在玩具设计中的应用范例,介绍了声控、红外控制、位置控制等玩具及教具的设计思路和方法。本文对于玩具设计与制造专业的师生以及玩具设计人员有一定的参考作用。  相似文献   
987.
Due to the variety of technical equipments and terminal layouts, research has produced a multitude of optimization models for seaside operations planning in container terminals. To provide a support in modeling problem characteristics and in suggesting applicable algorithms this paper reviews the relevant literature. For this purpose new classification schemes for berth allocation problems and quay crane scheduling problems are developed. Particular focus is put on integrated solution approaches which receive increasing importance for the terminal management.  相似文献   
988.
Because of severe affordability and skills constraints it is especially difficult to bring the Internet to rural areas of developing countries. But a number of promising alternatives are beginning to emerge. These are mainly designed to bring the Internet to non-users, that is, persons who do not actually come into direct contact with the technology. Such persons make up the bulk of the rural population in most developing countries. Two possibilities exist: one that involves intermediation at a distance (blending) and the other that takes place at close range (via say Internet kiosks). I use numerous examples to illustrate the potential of both these categories. For the minority of those who are able to actually use the Internet, costs can be lessened by a combination of communal institutions and technical sharing devices.  相似文献   
989.
Architectural design space exploration and early area budgeting for ASIC and IP block development require accurate high level gate count estimation methods without requiring the hardware being fully specified. The proposed method uses hierarchical and parameterizable models requiring minimal amount of information about the implementation technology to meet this goal. The modeling process flow is to: (1) create a block diagram of the design, (2) create a model for each block, and (3) sum up estimates of all sub-blocks by supplying the correct parameters to each sub-model. We discuss the model creation for a few parameterized library blocks as well as three communication blocks and a processor core from real IC projects ranging from 22 to 250 kgates. The average relative estimation error of the proposed method for the library blocks is 3.2% and for the real world examples 4.0%. The best application of this method is early in the design phase when different implementation architectures are compared.  相似文献   
990.
This paper analyzes a special type of technology evolution, referred to in the literature as disruptive technology vs. sustaining technology. In general, “old” products based on sustaining technology are perceived to be superior to the “new” ones based on disruptive technology. However, the latter have distinctive features that allow them to attract an exclusive set of customers. Examples include notebooks vs. netbooks, hard-disk drives vs. solid-state drives, laser printers vs. inkjet printers, etc. We consider a model with an established firm and an entrant firm that have heterogeneous product-offering capabilities: the established firm can offer either or both types of products, while the entrant firm can only offer new products. Firms make capacity, pricing, and quantity decisions that maximize their ex-ante profit. Within this framework, we analyze deterministic games with perfect information and stochastic games with uncertain valuation of the disruptive technology. Equilibrium decisions are discussed under various market conditions, as well as under dedicated vs. flexible capacity assumptions.  相似文献   
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