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91.
Wu J. Chen S. Li G. Istepanian R.H. Chu J. 《Automatic Control, IEEE Transactions on》2001,46(7):1162-1166
The pole-sensitivity approach is employed to investigate the stability issue of the discrete-time control system, where a digital controller implemented with finite word length (FWL), is used. A stability related measure is derived, which is more accurate in estimating the closed-loop stability robustness of an FWL implemented controller than some existing measures for the pole-sensitivity analysis. This improved stability measure thus provides a better criterion to find the optimal realizations for a generic controller structure that includes output-feedback and observer-based controllers. A numerical example is used to verify the theoretical analysis and to illustrate the design procedure 相似文献
92.
93.
For the problem of classifying an element (e.g., an unknown pattern) into one of two given categories where the associated observables are distributed according to one of two known multivariate normal populations having a common covariance matrix, it is shown that the minimum Bayes risk is a strict monotonic function of certain separability or statistical distance measures regardless of the a priori probabilities and the assigned loss function. However, for the associated conditional expected losses, strict monotonicity holds, if and only if a certain condition dependent on these probabilities and the given loss function is satisfied. These results remain valid for classification problems in which the observable can be transformed by a one-to-one differentiable mapping to normality. 相似文献
94.
Yufei Huang Feng Chu Chengbin Chu Yingluo Wang 《Journal of Intelligent Manufacturing》2012,23(1):73-89
This paper develops a new quantitative model to find the optimal number of new employees with a Newsvendor model in a pull
production system. This model allows learning, forgetting and variable wage. This paper also provides numerical results on
sensitivity analysis, and compares the numerical results in three different situations: the situation with both learning and
forgetting effect, that with learning effect but without forgetting effect and the situation with neither learning nor forgetting
effect. The conclusions drawn from the comparison may offer theoretical insight for human resource managers to make appropriate
employment decisions. 相似文献
95.
R. L. Meng T. H. Lin M. K. Wu C. W. Chu S. Z. Huang 《Journal of Low Temperature Physics》1982,48(5-6):383-388
High-pressure study has been made both resistively and magnetically on Eu1.2Mo6(S1–x
Se
x
)8. Superconductivity was detected at a lower pressure in samples forx0 than forx=0 in spite of the larger unit cell volume of the former. The superconductivity observed remains non-bulk up to 20 kbar. The maximum onset temperature of the superconductivity transition decreases withx.On leave from the Physics Institute, Chinese Academy of Sciences, Peking, China. 相似文献
96.
P.C-H. Chan D.G. Retzloff R. Mohamed B. Berdouzi C. Chicone D. Offin 《Chemical Engineering Communications》1987,57(1):105-138
The dynamical behavior for two parallel reactions in a continuous stirred tank reactor (CSTR) is considered. The global maximum number of steady states is five. Stability conditions are obtained. When the steady state is unique and unstable, a circulating attractor is proven to exist. The orbit structure is numerically found to consist of periodic orbits and chaotic behavior. 相似文献
97.
单正义 《山东电力高等专科学校学报》2006,9(2):15-17,21
随着我国社会经济的进一步转型,如何更有效地进行诚信教育已成为高校德育教育的一项重要课题。本文从诚信的内涵出发,以大学生诚信现状为切入点,并在此基础上对大学生诚信缺失的现象和存在的问题进行深入分析,提出构建高校学生诚信体系的对策或建议。 相似文献
98.
99.
The lead free Sn–Ag–y%Cu (y = 0.0, 0.5, 1.0 and 2.0) interconnect interfacial microstructures and the microstructure evolution under thermal treatment (isothermal aging, 150 °C/1000 h) were studied in detail by using surface microetching microscopy and cross section microscopy. The corresponding mechanical and reliability behaviors were evaluated by performing shear test and fracture mode analysis before and after the thermal treatment. The results indicate: (i) The interconnects could have different microstructures and intermetallic compound (IMC), depending on the Cu content. The Cu–Sn IMC could have microstructures that were clusters or protrusion-like, Augustine grass leaf-like, scissor-like, tweezers-like, etc. (ii) Ag3Sn IMCs were not observed at time zero for any interconnect groups, but they occurred after the aging for all groups. The Ag3Sn IMC could have different microstructures, again depending on Cu content. For low Cu content, the Ag3Sn IMCs were granules or nodules; for higher Cu content, Ag3Sn IMCs were plate-like. (iii) The growth of Ag3Sn plates was promoted by the growth of Cu–Sn IMCs, but indirectly linked to the Cu content. (iv) High Cu content (1.0 wt% and higher) could degrade the mechanical and reliability performances of the LF interconnect by providing a brittle joint, which was mainly achieved through the substantial growth of Cu–Sn IMCs and Ag3Sn plates. 相似文献
100.
首先着重分析了山西移动本地NGN的需求。阐述了山西移动NGN建设需要考虑的因素.最后就山西移动NGN的网络建设策略提出了具体的建议。 相似文献