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11.
光绪三十二年(1906),新疆布政使王树木丹组织了油苗普查,引进了钻采设备,在独山子开展了新疆石油工业的草创工作,但这项新兴的事业很快随清朝的灭亡而衰落了。民国7~12年(1918~1923),新疆省长杨增新再次组织石油采炼,但因经费不足,没有很大起色,而地方人士潘祖焕在汪家沟设厂,却首创了略有盈利的采炼实业,为新疆石油工业的二次兴盛作了贡献。本世纪40年代初,中苏合作,在独山子油矿建成了相当大的生产经营规模,新疆石油工业出现了第三个鼎盛时期。后来由于盛世才投靠国民党,反共反苏,与苏联关系恶化,独山子的石油采炼如昙花一现,迅速走向衰落。 相似文献
12.
冷英男 《辽宁石油化工大学学报》1994,(3)
提出了一个简单的理论模型.旨在为数据处理系统的性能评价提出一个理论框架.以此框架为基础,可形成实用的简单评估方法.该模型只含两个参数,它们是统计量,可用统计方法确定. 相似文献
13.
SHARED: An information model for cooperative product development 总被引:6,自引:0,他引:6
One fundamental issue in developing collaborative engineering systems is the representation of product information which supports communication and coordination. This product information includes not only the geometric and physical properties of the product and its parts, but also information about functions, constraints and the design rationale. In this paper, we describe an information model, SHARED, which was developed for encoding product information in DICE, a distributed and integrated environment for computer-aided engineering. SHARED provides multiple levels of both functional and geometric abstractions, multiple views and techniques for maintaining consistency between the various abstractions and views. These elements are essential for a good representation model of product information. The use of the SHARED model is illustrated through an example, depicting the various representations of a product as it evolves through the design process. The SHARED model has been implemented over a distributed OODBMS as a toolkit/framework for developing environments which need to model, manipulate and communicate product information between distributed cooperating applications, while supporting coordination between them. 相似文献
14.
David Geltner 《Energy Policy》1985,13(4):340-344
The author examines the transport energy consumption of developing countries and compares it with that of developed countries. These figures are found to suggest considerable scope for transport energy savings. Given the need for improved energy efficiency, the author moves on to consider transport in the context of the wider economy. Four broad policy approaches which can affect transport energy consumption are identified — information and training programmes, subsidies; pricing and tax policies; and administrative regulations. The author's primary conclusion is that the energy price changes of the last decade do not hold revolutionary implications for the transport sector. There remains, however, a need to improve efficiency in this sector. 相似文献
15.
关于加快发展南通市家用纺织业的思考 总被引:1,自引:0,他引:1
张进武 《南通纺织职业技术学院学报》2006,6(2):80-82
立足国内家用纺织品发展的大环境,在重点考察了南通、上海、无锡等地家用纺织业现状的基础上,就加快南通家用纺织业的发展提出了打造“南通国际家用纺织品研发(设计)中心”的具体思路。 相似文献
16.
17.
受阻胺类光稳定剂的现状及开发进展 总被引:10,自引:0,他引:10
受阻胺类光稳定剂(HALS)是继紫外线吸收剂之后的一种新型高效光稳定剂,简要介绍了国内外HALS的研究,生产现状及发展趋势。 相似文献
18.
消失模铸造在中国的应用及其发展 总被引:8,自引:0,他引:8
回顾国内外消失模铸造的发展概况,针对我国消失模铸造的应用现状,从模样材料及成型、涂料、造型、充型原理手方面,提出发展对策。 相似文献
19.
N. Kalra T. Lauwers D. Dewey T. Stepleton M. B. Dias 《Information Systems Frontiers》2009,11(2):117-128
Less than 3% of the 145 million blind people living in developing countries are literate (Helander, Prejudice and dignity: An introduction to community-based rehabilitation. New York: UNDP 1998). This low literacy rate is partly due to the lack of trained teachers and the challenges associated with learning to write
braille on a traditional slate and stylus. These challenges include writing from right to left, writing mirrored images of
letters, and receiving significantly delayed feedback. Extensive conversations with the Mathru Educational Trust for the Blind
near Bangalore, India, revealed the need for a robust, low-power, low-cost braille writing tutor. We present an iterative
and participatory process resulting in the creation and refinement of a prototype braille writing tutor system. This system
uses a novel input device to capture a student’s activity on a slate using a stylus and uses a range of techniques to teach
braille writing skills to both beginner and advanced students. We report on lessons learned from the implementation of this
project and from a 6-week pilot study at Mathru, and outline future directions for improvement.
相似文献
T. LauwersEmail: |
20.
《The Electricity Journal》2023,36(1):107238
Rural electrification is a crucial process of enhancing the modern energy access of rural communities which is an important global development goal. Electric cooperatives have played an important role as drivers of rural electrification worldwide, both historically and contemporaneously. The emerging role of cooperatives in rural electrification is yet to be examined in the context of East Africa, a region that experiences serious infrastructure deficits alongside widespread rural poverty. This study adopts a political economy perspective to explore the roles and challenges of cooperatives in rural electrification in Uganda. Through a high-level case study of two electric cooperatives, we show that while the cooperatives can deliver rural electrification, they face a series of political and economic challenges in fulfilling their mission. To enhance rural electrification through cooperatives, the challenges should be addressed by policy solutions: (1) providing more support to rural households that cannot afford electricity; (2) providing further support to cooperatives to avoid overburdening the community; (3) enhancing investment to upgrade the grid and extend its geographical coverage; and (4) exploring new financial and technological options for rural electrification. We expect the findings of this study to be useful to policymakers, implementers, cooperatives, and international donors currently working in rural electrification in Africa and beyond. 相似文献