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91.
有限元数值模拟试井技术,可通过描述不同网格的瞬变压力对测试范围内各个小单元进行精细描述.综合运用解析试井、数值试井联带分析方法,将测试动态成果与地质静态成果有机结合、相互补充,可实现对复杂断块油气藏的精细描述,达到一口井搞清一个小型复杂断块油气藏的目的. 相似文献
92.
叙述了从铅阳极泥回收金银后的渣料中综合回收有价金属的生产实践。根据渣料性质,将火法和湿法工艺相互结合,使渣料中的锑、铋、金、银、铅、铜得以较彻底的分离和回收。 相似文献
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Sivakumar Bakthavachalu Miguel A. Labrador 《International Journal of Communication Systems》2004,17(8):763-778
The TFRC protocol has been proposed as a TCP‐friendly protocol to transport streaming media over the Internet. However, its deployment is still questionable because it has not been compared to other important protocols, analysed in the presence of important mechanisms, such as the explicit congestion notification (ECN), and studied under more realistic network conditions. In this paper, we address these three aspects, including other congestion control protocols not considered before in the same investigation, such as TCP Tahoe, Reno, Newreno, Vegas, Sack, GAIMD, and the Binomial algorithms, the effect of using ECN in the friendliness of the protocols, and the fairness of the protocols under static and dynamic network conditions. We found that TFRC can be safely deployed in the Internet if competing with TCP Tahoe, New Reno and SACK since fairness is achieved under all scenarios considered. We also found that ECN actually helps in achieving better fairness. However, fairness problems arise when TFRC competes with TCP Reno, GAIMD, SQRT or IIAD in static or dynamic conditions, or both. We used normalized throughput, fairness index, and convergence time as the main performance metrics for comparison. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
96.
总结了开发生产低熔融指数聚丙烯的试验过程与结果,通过优选催化剂、优化操作过程、控制加氢量,生产出质量稳定可靠的熔融指数在0.2~0.5g/l0min之间的低熔融指数聚丙烯. 相似文献
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主要研究了单层工业厂房可靠性模糊综合评判法的基本理论与实施方法.通过一工程实例,表明用这种定量方法来处理厂房可靠性评判中的大量不确定信息是科学、合理而又实用的. 相似文献
99.
The engineering and management of human safety is an important societal objective that includes extensive efforts by governments, both legislative and administrative, to enhance the health and safety of the public. Although the achievement of safety goals depend primarily on individuals and organizations responsible for safety, much support is drawn from expertise in diverse scientific and engineering disciplines. The activities range from structural safety (dams, tunnels, bridges to tall buildings) to safe operation of hazardous industrial installations (energy generation facilities, LNG terminals, petrochemical plants) to transportation systems (airline, rail, car safety) to technologies designed to minimize adverse impacts on the environment. All these activities are crucially concerned with risk: with the likelihood and the probable effects of various measures on life and health. We have developed a unified rationale and a clear basis for effective strategic management of risk across diverse sectors. Safety is an important objective in society but it is not the only one. The allocation of society's resources devoted to safety must be continually appraised in light of competing needs, because there is a limit on the resources that can be expended to extend life. The paper presents the Life Quality Index (LQI) as a tool for the assessment of risk reduction initiatives that would support the public interest and enhance safety and quality of life. The paper provides an intuitive reformulation of the LQI as equivalent to a valid utility function that is consistent with the principles of rational decision analysis. The LQI is further refined to consider the issues of discounting of life years, competing background risks, and population age and mortality distribution. The LQI is applied to quantify the societal willingness-to-pay, which is an acceptable level of public expenditure in exchange for a reduction in the risk of death that results in improved life-quality. 相似文献
100.