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21.
P V Ananthapadmanabhan A V Bapat A K Das B K Karan R Majumder R K Marwah D S Patil S V K Rao V K Rohatgi K G Sankaran P Satyamurthy R Sharma P B Shrivastava M K Totlani N Venkat-Ramani F A Akopov A V Karpukhin V V Kirillov V I Maksimenko A S Prokop A I Romanov B V Roshin E V Shishkov A S Tikhotsky V I Zalkind N I Antonov V V Brajevsky D K Burenkov V A Efremov V N Sukhov 《Sadhana》1982,5(3):169-195
This paper summarizes the major results of the joint Indo-Soviet experiment for testing the Indianmhd generator channel section, designed and fabricated at the Bhabha Atomic Research Centre, Bombay, which was carried out at the U-02 facility in Moscow, USSR, in May 1980. The total test duration was 65 hours and included electrophysical tests and life tests under applied electric fields. The main purpose of the tests was to substantiate the physical concepts, computer codes, design features and special processing techniques involved in the development ofmhd generators for the Indian pilot plant at Tiruchirapalli. The experimental observations on the phenomena of heat transfer to the walls, gas dynamics in the channel, electrical characteristics of the generator and near-electrode processes including the analysis of arc spots correlate with the theoretical estimates based on present understanding of the physical processes occuring in similarmhd generators. The post-operational inspection of the channel section and extensive investigation of materials through microscopic analysis, chemical analysis and x-ray analysis are also reported in this paper. The joint test programme has clearly demonstrated the definite operating capability of the test section and has given sufficient information and encouragement for building better and improved channels for the future. 相似文献
22.
Triglyceride composition of chrysalis oil,an insect lipid 总被引:1,自引:0,他引:1
Chrysalis oil, an insect fat obtained from the spent silk worm pupae, Bombyx mori, is a by-product of sericultural industry
and represents a potential source of 1750 tons of linolenic-rich oil per annum for India. Fatty acid and triglyceride compositions
of chrysalis oil have been determined by the combination of the techniques of lower temperature segregation, lipolysis, thin
layer and gas liquid chromatography. Percentage contents of the component acids are: C14:0, 0.6; C16:0, 19.3; C18:0 3.9; C18:1, 17.7; C18:2, 9.8, and C18:3, 48.7. Major component triglycerides are, LLnLn, 5.2%; PLnO, 6.4%;OLnLn, 9.6%; LnLnLn, 10.5% and PLnLn, 14.0% (P, palmitic;
O, oleic; L, linoleic and Ln, linolenic acids. On low temperature crystallization, Chrysalis oil yielded two fractions amounting
together to 40% of the total with composition quite similar to that of linseed oil. 相似文献
23.
Majumdar K.K. Majumder D.D. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2004,34(2):877-887
Uncertainty management in dynamical systems is receiving attention in artificial intelligence, particularly in the fields of qualitative and model based reasoning. Fuzzy dynamical systems occupy a very important position in the class of uncertain systems. It is well established that the fuzzy dynamical systems represented by a set of fuzzy differential inclusions (FDI) are very convenient tools for modeling and simulation of various uncertain systems. In this paper, we discuss about the mathematical modeling of two very complex natural phenomena by means of FDIs. One of them belongs to the atmospheric cybernetics (the term has been used in a broad sense) of the genesis of a cyclonic storm (cyclogenesis), and the other belongs to the bio-medical cybernetics of the evolution of tumor in a human body. Since a discussion of the former already appears in a previous paper by the first author, here, we present very briefly a theoretical formalism of cyclone formation. On the other hand, we treat the latter system more elaborately. We solve the FDIs with the help of an algorithm developed in this paper to numerically simulate the mathematical models. From the simulation results thus obtained, we have drawn a number of interesting conclusions, which have been verified, and this vindicates the validity of our models. 相似文献
24.
针对现有工业园区综合能源系统能量管理协调性和经济性较差的问题,文章提出了考虑供能可靠性的综合能源系统能量管理方法。首先,构建了综合能源系统的典型运营模式,建立了系统中主要元件的效能与经济模型;其次,考虑了设备的运行维护成本、园区与主网的能量交互成本,构建了以综合发电成本为目标函数,以冷/热/电负荷平衡、机组爬坡功率、供能可靠性为约束条件的综合能源系统经济调度模型;然后,针对能量管理时序问题改进了遗传算法的编码方式,提出了新的优化算法;最后,通过算例验证了文章所述方法的有效性和实用性。 相似文献
25.
渤海A油田浅层大位移井最大水垂比为2.98,突破了渤海湾水垂比的现有极限。其浅部地层疏松,井眼轨迹控制难度大,泥岩易水化膨胀,频繁出现倒划眼困难和下套管遇阻等复杂情况。针对以上问题,在定向井轨迹设计、大位移井安全钻井周期、井身结构优化、大位移井摩阻扭矩及钻井液性能等方面进行了技术研究。结果表明,采用大位移井均布设在外排井槽,保持井斜角为73°~76°、浅部地层使用大弯角马达,深部地层使用旋转导向进行钻进,大位移井安全钻井周期约为32 h,建议钻进过程中提高机械钻速;井深在4 000~4 500 m的大位移井,推荐采取五开井身结构;反演得到大位移井套管内摩阻系数为0.25、裸眼内摩阻系数为0.35~0.40,推荐Φ244.48 mm套管选择69.94 kg/m(47 PPF),作业时可根据实际情况选择部分漂浮、全漂浮+旋转以及部分漂浮+旋转这3种下套管方式;储层段采用"预防为主+防堵结合"思路,在传统的无固相钻井液中加入超细碳酸钙,提高承压封堵性能及储层保护性能。该研究成果对于浅层大位移井的设计和施工具有一定参考意义。 相似文献
26.
为了研究不同形状微织构的分布方式、数量、密度、摆放角度与深度等对不对中气体箔片止推轴承承载性能的影响,结合逐点超松弛迭代法(SOR)与有限差分法(FDM)求解气体箔片止推轴承Reynolds方程,通过MatLab仿真计算得到不同微织构参数下轴承的承载力与摩擦力矩等。计算结果表明:微织构分布于止推轴承基座区与楔形区〖JP2〗交界处时,相较于其他分布方式,轴承承载力均明显提高;不同形状微织构的最大截面沿止推轴承径向方向摆放时,轴承性能改善最佳。研究表明:存在最优的微织构数量、密度与深度,可使止推轴承在较小的摩擦力矩下有更高的承载性能;相较于无微织构轴承,椭圆形微织构在最优微织构参数下可使轴承其承载力提升41.22%,摩擦力矩降低0.81%。 相似文献
27.
28.
Qinli Wang Guizhong Liu Haidong Wang Yuchen Chen Rui Deng Lijun He Zhao Liu 《Multimedia Tools and Applications》2014,72(3):3105-3142
With the explosive growth of multimedia applications, video transmission over HSDPA networks has attracted more and more attentions. Particularly in the last few years, lots of special transmission schemes have been proposed to improve the end-to-end qualities of mobile video applications. However, due to lack of a common video delivery simulation platform over HSDPA networks, the researchers have met obstacles in evaluating and comparing the performance of these schemes in a unified simulation environment. To fill this gap, a common system-level video transmission simulation platform is proposed in this paper, which is implemented specially for the HSDPA networks. To the best of our knowledge, this platform is the first one in integrating the video encoder/decoder, the video quality evaluator and the HSDPA simulator together. In this way, the researchers can study and analyze not only the overall system performance of the video-aware cross-layer transmission solutions, but also explore the influence and interaction of those separate sub-layers in the HSDPA wireless networks, such as the video application-layer, the transmission control layer, the HSDPA MAC layer, and the physical layer. Moreover, to test and verify our simulation platform, we implement eight representative fast scheduling algorithms over the HSDPA networks, and evaluate their transmission performances for the H.264/AVC video applications. Experimental simulation results demonstrate the effectiveness and rationality of our simulation system. 相似文献
29.
一种基于启发式奖赏函数的分层强化学习方法 总被引:4,自引:0,他引:4
针对强化学习在应用中经常出现的维数灾问题,即状态空间的大小随着特征数量的增加而发生指数级的增长,以及收敛速度过慢的问题,提出了一种基于启发式奖赏函数的分层强化学习方法.该方法不仅能够大幅度减少环境状态空间,还能加快学习的收敛速度.将此算法应用到俄罗斯方块的仿真平台中,通过对实验中的参数进行设置及对算法性能进行分析,结果表明:采用启发式奖赏函数的分层强化学习方法能在一定程度上解决维数灾问题,并具有很好的收敛速度. 相似文献
30.