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31.
依据丰满漉域的水文气象资料,计算丰满流域可能最大暴雨,推求白丰区间的可能最大洪水并进行成果合理性分析. 相似文献
32.
小容量机组保护监控一体化 总被引:2,自引:2,他引:0
以数字信号处理器(DSP)和复杂可编程逻辑器件(CPLD)为硬件平台,研制了新一代面向中、小型水电站的综合自动化模块.充分发挥MB40智能可编程逻辑控制器(iPLC)及MB100系列保护测控系统的技术优势,将小型水电站的保护装置做成模块插件,融入监控系统,降低了小型水电站自动化设备的成本,为推出真正意义上的面向小型水电站的"五合一"产品打下坚实的基础. 相似文献
33.
对37名骨密度(BD)低下的飞行员(实验组)和BD正常的48名飞行员、100名地面人员(正常对照组)进行了BD和血清TT_3、TT_4、TSH IRMA、CT、PTH、E_2和T放射免疫测定。结果显示,实验组BD均值明显低于对照组(p<0.01),血清TT_3、TT_4、CT、E_2(女性)和T(男性)均值与对照组比较,大多数年龄存在着显著或非常显著差异(p<0.05或p<0.01)。同时对飞行人员BD与几种内分泌激素关系进行了探讨。 相似文献
34.
探讨了裂解C_5馏分就近集中分离综合利用和分散直接利用,以及建设单独分离双环戊二烯装置发展下游精细化工产品的综合利用策略。 相似文献
35.
Lin Yuan Kesavan H.K. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》1998,28(3):488-491
Kapur et al. (1995) introduced the MinMax information measure, which is based on both maximum and minimum entropy. The major obstacle for using this measure, in practice, is the difficulty in finding the minimum entropy. An analytical expression has already been developed for calculating the minimum entropy when only variance is specified. An analytical formula is obtained for calculating the minimum entropy when only mean is specified, and numerical examples are given for illustration 相似文献
36.
Kow Ming Chang Yuan Hung Chung Gin Ming Lin 《Electron Device Letters, IEEE》2002,23(5):255-257
Studies the anomalous variations of the OFF-state leakage current (IOFF) in n-channel poly-Si thin-film transistors (TFTs) under static stress. The dominant mechanisms for the anomalous IOFF can be attributed to (1) IOFF increases due to channel hot electrons trapping at the gate oxide/channel interface and silicon grain boundaries and (2) IOFF decreases due to hot holes accumulated/trapped near the channel/bottom oxide interface near the source region. Under the stress of high drain bias, serious impact ionization effect will occur to generate hot electrons and hot holes near the drain region. Some of holes will be injected into the gate oxide due to the vertical field (~(V_Gstress V_Dstress)/T OX) near the drain and the others will be migrated from drain to source along the channel due to lateral electric field (~V_Dstress/LCH) 相似文献
37.
38.
Jing Yuan Yury Stepanenko 《International Journal of Adaptive Control and Signal Processing》1992,6(2):111-126
A new adaptive controller is presented here for rigid-body robotic manipulators. It is stable and robust with respect to a class of external disturbances. The robustness of the adaptive controller is established without the ‘slow-varying’ assumption and the computationally demanding regressor matrix. The control law consists of a non-adaptive PD control part and an adaptive control part. It uses two adaptive matrices to compensate two uniformly bounded coefficient matrices derived from the original dynamics. A α σ|q?|-modified adaptive law is designed to adjust the adaptive matrices. A Lyapunov-type stability analysis indicates that the closed-loop system is uniformly ultimately bounded. The tracking error and compensation error will eventually converge into a closed region, which can be made arbitrarily small by adjusting the controller parameters. Simulation results are included to demonstrate the performance of the proposed controller. 相似文献
39.
A pilot-scale fluidised pellet bed (FPB) bioreactor, which combines chemical coagulation, biological degradation, particle pelletisation and separation in one unit, was applied for onsite wastewater treatment and reuse. As a result of rational use of inorganic coagulant and organic polymer and moderate mechanical agitation, spherical particles were generated in the upflow column and a well-fluidised bed was formed. With a continuous supply of dissolved oxygen through a recycling loop, an aerobic condition was kept in the bottom section of the FPB column. Under such conditions the pellets in the FPB column showed the following characteristics: (1) compact structure and high density; (2) rich in microorganisms; and (3) high MLSS and MLVSS concentrations. Therefore, the FPB bioreactor achieved more than 90% removal of SS, COD, BOD and TP from raw domestic wastewater within a total hydraulic retention time (HRT) of only about 30 minutes. It also showed nitrification and denitrification ability and the TN removal could be about 50% as the recycling ratio was increased to 1:1. The treated water quality is generally competitive with the secondary effluent from a conventional activated sludge process. With these advantages the FPB bioreactor is recommendable as a compact system for onsite wastewater treatment and reuse. 相似文献
40.
应用单组中子微扰理论,对辐照后控制棒钴吸收体内活度分布进行理论分析,得到活度分布计算的解析表达式。对高通量工程试验堆(HFETR)首次出堆的2根控制棒钴吸收体进行数值计算。利用钴靶活度水下测量装置进行这2根钴吸收体活度分布的实验测量。计算与实验测量结果相符。通过理论计算所得到的活度分布可作为辐照后~(60)Co同位素分装依据。本文得到的控制棒相对价值曲线理论计算值与实验测量结果符合良好。 相似文献