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71.
�ձ������ٽ���Ȼ�����ѵ����ߴ�ʩ������ʾ 总被引:9,自引:3,他引:6
日本政府采取一整套行之有效的政策措施来促进天然气消费,这套政策措施是:以立法的形式促进天然气消费,大力发展燃气企业,支持与鼓励天然气发电,大力发展燃气空调,支持和资助天然气实用技术的开发,以各种方式会同各家公司建立某些机构促进日本天然气产业的发展,采取财政信贷措施支持天然气的进口。对我国的启示是:建立和完善与天然气相关约法律法规体系,成立一些中介机构,鼓励开拓天然气利用的新途径,采取优惠措施鼓励居民使用天然气,同时政府应积极参与和支持新技术的研究、开发、应用和推广。 相似文献
72.
由于天然气输气管线埋在地下,在通球清管过程中,球的运行情况不能直接观察,管线入口和出口压力在球运行过程中的变化也不能提前预测,也难准确控制进气量,使球能以1m/s的速度到达出口,为此进行了天然气输气管线清管通球计算机仿真系统的设计与实现的研制。该仿真系统是在深入分析和研究天然气输气管线清管通球运行规律的影响因素的基础上,以数据库管理、计算机仿真技术和人工智能等新技术为主要工具来开发的。着重介绍了该仿真系统的总体结构与功能设计,软件编程与调试。该仿真系统能真实仿真清管球在管线内运行,通过对靖边—榆林输气管线多次清管通球的运行过程实际模拟,其符合率在93%以上。 相似文献
73.
J. Schanda 《Color research and application》2007,32(3):233-235
This is a comment to the editorial by J. Hutchings on “Talking about Color… and Ethics.” © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 233–235, 2007 相似文献
74.
This paper describes the development of a conceptual model of an interaction system for future human-computer interaction. It is suggested that an integrated system is the most promising solution for diverse users and tasks. A ' hybrid interaction system' is considered, which tries to efficiently direct manipulation, menu selection, and natural language. The mechanism of the natural language interface module is described in more detail. Finally, the allocation of functionalities for generalized tasks on the conceptual model is considered from the taxonomic approach. 相似文献
75.
GEOCHEMICALCHARACTERISTICSOFTHECOAL-FORMEDGASESIHTHEEASTOFTHECENTRAL-ASIACOAL-FORMEDGASACCUMULATIONDOMAIN──SERIESSTUDYⅡONTHEC... 相似文献
76.
In this study, experimental and three-dimensional numerical studies were performed to investigate the effects of plate spacing and temperature difference on natural convection between isothermally heated upward-facing lower horizontal plate and externally insulated horizontal upper plate. Air is used as the heat transfer medium. Rayleigh number varied in the 1108–2.339 × 105 range. Several numerical simulations for three-dimensional steady laminar and turbulent flows heat transfer were carried out using a commercial CFD code Fluent 6.2. Results have shown that there is a good agreement between the numerical and present experimental results as well as with available data in literature. 相似文献
77.
Influence of thermal boundary conditions on natural convection in a square enclosure partially heated from below 总被引:1,自引:0,他引:1
Nader Ben Cheikh Brahim Ben BeyaTaieb Lili 《International Communications in Heat and Mass Transfer》2007
Natural convection in air-filled 2D square enclosure heated with a constant source from below and cooled from above is studied numerically for a variety of thermal boundary conditions at the top and sidewalls. Simulations are performed for two kinds of lengths of the heated source, i.e., a small and a large source corresponding to 20% and 80% of the total length of the bottom wall, respectively. The Rayleigh number varied from 103 to 107. Results are presented in the form of streamline and isotherm plots as well as the variation of the Nusselt number and maximum temperature at the heat source surface. Comparisons among the different thermal configurations considered are reported. 相似文献
78.
There have been extensive attempts in recent years to perform spatial equilibrium analysis of commodity markets, particularly that of energy. Most of these attempts have been based on linear programming transportation models, and more recently quadratic programming models. Unfortunately, neither of these modelling approaches can deal with the case of multi-commodity analysis with non-symmetric regression coefficients. In this paper, we overcome this problem by employing the linear complementarity programming model. In addition, we show how the model can be applied to coal and gas energy flows within a single region. Future potential applications of the model are also implied. 相似文献
79.
在10 ̄(-5)_eV-20MeV中子能量范围内对天然汞的中子核数据进行评价。评价内容包括总的、弹性、去弹、总非弹、30条分立能级、连续非弹、(n,2n)、(n,3n,)、(n,n'P)、(n,n'α)、(n,P)、(n,α)、(n,d)、(n,t)和(n,γ)截面;次级中子角分布;双微分截面(DDCS);γ射线产生数据等。评价根据有效实验数据(至1993年)和UNF-92 ̄[1]理论计算。评价数据以ENDF/B6格式录入中国评价核数据库CENDL-2.1版(MAT=1800),并提供核工程有关部门使用。 相似文献
80.
Infiltration and localization of preferential infiltration zones at the dam abutment are measured using radioactive tracer tests of flow in boreholes,meanwhile interconnection between boreholes and the energing water points is analysed.The theory and practice of radioactive tracer synthetic detective method are described to give methods and calculation formulae used under the condition of stable flow in single well to measure permeability coefficient and hydrostatic heads.Major single hole techniques including measurement for seepage line,velocity,rate of seepage flow and relationship of recharge of groundwater in aquifers are introduced briefly.The possibilities offered by natureal tracers are analysed,uincluding electric-conduct,pH-value and temperature of water as well as stable isotopes(D,^18O) and tritium.Furthermore,the sensibilities of this theory and methods were confirmed by detecting seepage flow field of Xinanjiang Dam. 相似文献