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61.
首先以 HERMLE C1200 U 为例分析了五轴铣削加工中心的基本结构,然后据此给出了涉及多轴铣削加工中心后置处理角度分配和坐标变换的数学模型,最后介绍了以此数学模型为核心,为UG 软件开发的后置处理软件 UG-HERP1.0的解决方案。 相似文献
62.
Stakeholder involvement is essential to the development of a total maximum daily load (TMDL) and its implementation plan. A tool, beyond a simulation model, is needed to support the decision making process that requires negotiation and compromise among stakeholders. The decision support system (DSS) described herein has a TMDL module to calculate various combinations of point and nonpoint loads that can meet the water quality criteria. Its Consensus module allows stakeholders to formulate, evaluate, modify, and vote for alternatives. The DSS displays bar charts for pollution loads from various subwatersheds and attributes the nonpoint loads to land uses. The water quality consequence of the pollution loads is output in maps, which shows sections meeting criteria in green and those not in red. The DSS requires a front end effort of site specific adaptation and model calibration. An Internet-based stakeholder process was developed to allow more concerned citizens to participate in management decisions. 相似文献
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Humanitarian psychological support as an organized field is relatively young. Pioneers in the field were involved primarily in providing psychological support to refugees and internally displaced persons in conflict and nonconflict situations. This article describes basic principles for the design of psychological support programs and interventions. The International Federation of Red Cross and Red Crescent Societies (IFRC) began a psychological support program in 1991. The IFRC chose psychological first aid as its model for implementation in developing countries. Psychological first aid fits all the principles for psychological support program design and is adapted to individual communities. The first generation of psychological support programs differed dramatically depending on the countries in which they were developed. A second generation of psychological support programs evolved in response to the earthquake/tsunami of December 26, 2004. The Inter-Agency Standing Committee international guidelines consolidated the advances of second-generation programs and provided a clear indication of the wide acceptance of the importance of psychological support. A glimpse is provided of the third generation of psychological support programs, and an admonition is made for a more empirical evaluation of the effectiveness of interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
一种新型同位素示踪剂载体及应用 总被引:2,自引:0,他引:2
同位素沾污、低注井同位素示踪剂因沉降造成的上返速度慢或无法上返、大孔道地层同位素示踪剂失踪等是影响注水开发油田后期吸水剖面测井资料质量的主要问题。同位素示踪剂载体的物理参数,尤其是其密度,是产生上述问题的重要因素。通过对同位素示踪剂载体技术指标优选而生产的一种新型同位素示踪剂,可以解决低注井同位素上返速度慢的问题,并能有效识别大孔道地层,减少同位素沾污。这种同位素示踪剂载体已在河南油田吸水剖面测井中应用,并见到了很好的效果。 相似文献
66.
油田勘探数据中心及辅助支持系统研究 总被引:2,自引:1,他引:1
周霞 《计算机工程与应用》2003,39(24):202-204
文章简要介绍胜利油田近年来致力于勘探数据中心建设及辅助支持系统研究的背景、主要研究内容及进展情况,探讨了石油勘探行业在信息化时代利用先进的数据管理理念和技术对勘探工作提供数据支持和应用支持的尝试,对于其它油田勘探行业具有一定的借鉴意义。 相似文献
67.
A. Hynaux C. Sayag S. Suppan J. Trawczynski M. Lewandowski A. Szymanska-Kolasa G. Djga-Mariadassou 《Catalysis Today》2007,119(1-4):3-6
Hydrodesulfurization (HDS) is part of the hydrotreating process, which is an ensemble of several reactions (HDN, HDO, HDS, etc.) taking place simultaneously at the industrial scale. Only sulfur is currently submitted to drastic Europeans specifications and conventional commercial catalysts cannot reach the specifications at low cost. This paper presents the behavior of a potential substitute catalyst tested for the deep HDS of a model molecule such as the dibenzothiophene (DBT). The substitute is molybdenum carbide supported on a mesoporous carbon black composite of surface area 240 m2 g−1. A global kinetic study of the deep HDS of DBT (300 ppm S) was performed at 623 K and 5.0 MPa and a global kinetic model was proposed as well as global rate constants were calculated to obtain theoretical plots of concentration versus contact time to compare with the experimental data. The kinetic model and global kinetic orders were confirmed as an acceptable correlation was found between calculated and experimental data. Furthermore, the determination of the global kinetic orders indicated that two types of active sites must be present on the surface in order to explain the observed results. 相似文献
68.
通过对工作面端面冒顶原因及支护系统的分析得出,加大液压支架的流量可以加快移架速度,降低冒顶事故率,提高生产效率。 相似文献
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锚喷支护作为地质灾害治理中山体过坡支护的一杆方法.具有安全、优质、高效、灵活等特点,本文以吉林省安图县两江水利枢纽泄洪洞出口右侧高边坡治理工程为例.对锚喷支护施工技术作一简单介绍。 相似文献