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71.
发展三次采油为主的提高果收率新技术,具有很大的潜力。如果通过各种三次采油方法提高采收率12.4%,那么由此增加的可采储量相当于全国目前剩余可采储量的56%。鉴于各种三次采油方法中,聚合物驱非常适合我国陆相储层的地质条件,在当前应首先抓紧矿场聚合物驱的工业化试验应用,尽快形成生产能力。其次是加强化学复合驱提高采收率机理的研究,因为这项技术提高采收率的幅度是聚合物驱的两陪多。但是此法使用的表面活性剂量太大,机理复杂,技术难度大,目前推广使用困难多,故需进一步加强研究。第三是积极探索微生物采油技术、注气混相驱和非混相驱、热采、各种物理场提高采收率等技术的研究。 相似文献
72.
利用工厂现有优势资源,自主对故障率逐步升高的仪表空气干燥器控制系统进行升级改进,从而提高重要单元设备运行的可靠性。 相似文献
73.
针对在煤气回收和放散调试过程中发现的问题,通过改进转炉煤气回收和放散控制系统,增加气动三通阀控制联锁信号,保证放散的高度可靠性和煤气自动回收的高度安全性。 相似文献
74.
张健 《电脑编程技巧与维护》2012,(18):56-57,107
由于TCP协议直接应用到卫星网络中将可能会导致网络性能下降,因此针对卫星网络的特点,分析了传播时延、高误码率、非对称连接方式等特点对TCP协议性能的影响,对主要解决方法进行了分析、比较现有的几种解决方法利弊,应根据具体应用采用相应的解决方案。 相似文献
75.
大通湖是洞庭湖区的重要组成部分,近年其水质状况呈现恶化态势,正通过实施水系连通工程,以期改善其水环境。基于MIKE21构建大通湖区水系连通工程的二维水动力-水质数学模型,选取总氮和总磷作为水质指标,模拟不同连通调度方案下大通湖的氮磷浓度变化,采用滞水区面积比例、浓度变化指数、换水率和水质浓度改善率,评估6个连通方案下大通湖水环境的改善效果。结果表明:通过实施引水调度方案能够有效改善大通湖水环境,当引水前期流量取30 m~3/s,出口水位控制在25.48 m时和引水后期流量保持为30 m~3/s不变,出口水位调整至25.88 m时,大通湖水环境改善效果最佳。本研究可为实施水系连通工程,改善类似湖泊水环境和提高引水调度效率提供参考。 相似文献
76.
Mosleh M. Abualhaj Abdelrahman H. Hussein Qasem M. Kharma Qusai Y. Shambour 《计算机系统科学与工程》2021,38(2):251-264
A considerable number of applications are running over IP networks. This increased the contention on the network resource, which ultimately results in congestion. Active queue management (AQM) aims to reduce the serious consequences of network congestion in the router buffer and its negative effects on network performance. AQM methods implement different techniques in accordance with congestion indicators, such as queue length and average queue length. The performance of the network is evaluated using delay, loss, and throughput. The gap between congestion indicators and network performance measurements leads to the decline in network performance. In this study, delay and loss predictions are used as congestion indicators in a novel stochastic approach for AQM. The proposed method estimates the congestion in the router buffer and then uses the indicators to calculate the dropping probability, which is responsible for managing the router buffer. The experimental results, based on two sets of experiments, have shown that the proposed method outperformed the existing benchmark algorithms including RED, ERED and BLUE algorithms. For instance, in the first experiment, the proposed method resides in the third-place in terms of delay when compared to the benchmark algorithms. In addition, the proposed method outperformed the benchmark algorithms in terms of packet loss, packet dropping, and packet retransmission. Overall, the proposed method outperformed the benchmark algorithms because it preserves packet loss while maintaining reasonable queuing delay. 相似文献
77.
Julio J. Garcia‐Sabater Juan A. Marin‐Garcia M. Rosario Perello‐Marin 《人机工程学与制造业中的人性因素》2012,22(2):99-112
The purpose of this article is to present an evolutionary model of the enablers and inhibitors affecting the implementation and sustainability of continuous improvement. With this aim, a qualitative study using the grounded theory was carried out. Interviews were conducted with managers responsible for continuous improvement in first‐tier suppliers in the automotive sector. As a result, two existing lines of research in the continuous improvement literature are synthesized: on one hand, the literature concerning the enablers and barriers associated with continuous improvement sustainability; and on the other, the literature concerning the evolutionary model. © 2011 Wiley Periodicals, Inc. 相似文献
78.
Amir Hossein NikoofardHossein Hajimirsadeghi Ashkan Rahimi-KianCaro Lucas 《Applied Soft Computing》2012,12(1):100-112
This paper presents a proposal for multiobjective Invasive Weed Optimization (IWO) based on nondominated sorting of the solutions. IWO is an ecologically inspired stochastic optimization algorithm which has shown successful results for global optimization. In the present work, performance of the proposed nondominated sorting IWO (NSIWO) algorithm is evaluated through a number of well-known benchmarks for multiobjective optimization. The simulation results of the test problems show that this algorithm is comparable with other multiobjective evolutionary algorithms and is also capable of finding better spread of solutions in some cases. Next, the proposed algorithm is employed to study the Pareto improvement model in two complex electricity markets. First, the Pareto improvement solution set is obtained for a three-player oligopolistic electricity market with a nonlinear demand function. Then, the IEEE 30-bus power system with transmission constraints is considered, and the Pareto improvement solutions are found for the model with deterministic cost functions. In addition, NSIWO algorithm is used to analyze this system with stochastic cost data in a risk management problem which maximizes the expected total profit but minimizes the profit risk in the market. 相似文献
79.
对FK6-600牵伸加弹机主传动中"格里森"制圆弧螺旋齿轮的失效情况进行了考察和研究。通过对德国DIN867和我国JB110标准的分析,采用了等顶隙收缩齿并对其进行了合理改进,同时在现场安装工作中采取了必要措施,取得了较好的技术经济效果。 相似文献
80.
D. T. Cambell and D. W. Fiske (1959) made the now-obvious statement that measures of the same variable made by different methods should agree (converge) and certainly should agree better than measures of different variables made by those several methods. Almost everyone accepted that statement, yet the multitrait–multimethod matrices published today show little or no improvement over the published examples cited in 1959. The article raised the conceptual problem of how a variable and its measurement should be linked and the methodological problem of clarifying the nature of methods and their effects. Given these unresolved problems, it is perhaps not surprising that the question of the appropriate statistical analysis of these matrices has also no consensual answer. Perhaps methods and traits or contents are so thoroughly intertwined that their interaction cannot be adequately analyzed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献