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951.
基于模糊神经网络的感应加热电源温度控制 总被引:1,自引:0,他引:1
通过对原有感应加热电源温度控制方法的分析,提出了一种适合于非线性系统基于模糊神经网络的温度控制方法,并介绍了该系统的组成及实现方法。 相似文献
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LUKui TANGPei-rongt YANGWei-min 《中国矿业大学学报(英文版)》2005,15(1):48-51
The control system, which includes structure, the composition of software and hardware, the form of PID control system and its systematic closed-loop, was used in No.4236 full-mechanized coal face of Xinlongzhuang mine.The typical fuzzy PID control system structure was investigated, and a simplified fuzzy PID control system was taken the place of the complex three-dimension fuzzy controller. Based on the parameter relation between fuzzy controller and normal PID controller, a common method of parameter adjustment of PID controller was summed up and the computer simulation was realized. This system can overcome the problems of large delay, nonlinear, poor running environment and great load change in the full-mechanized coal face. The simulating investigation indicates that the designing method of fuzzy controller is simple and feasible. 相似文献
954.
Effect of heparin on high glucose induced proliferation and expression of matrix metalloproteinases in normal human mesangial cells 总被引:1,自引:0,他引:1
Zhou Qiao-ling Yasumoto Yuichiro Tsukamoto Masatoshi Nozaki Tsuyoshi Sogabe Atsushi Harada Kouji Zhang Yi-xiang Lin Xiao-yan Zhang Yang-de Arima Terukatsu 《中南工业大学学报(英文版)》2005,12(1):359-364
Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process. Its precise mechanism is not fully
known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase,
and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro.
The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration
and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture
medium were 0, 25, 50, 100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and
Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium.
They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence
of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low
glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed
a 0.61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low
glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when
compared to cells grown without heparin. In Western blot analysis, MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high
glucose medium. Incubation of heparin further increased expression of MMP1, MMP2, MMP3 and MMP9. Conclusions This study suggests that glucose can accelerate mesangial cell proliferation while heparin can reduce proliferation, being
more obvious at high glucose concentrations. Higher glucose concentrations led to increased MMP expression, which may take
part in the regulation of mesangial matrix synthesis and degradation. Addition of heparin resulted in a corresponding increase
in MMP expression, most notably at high glucose concentrations, indicating a potentially renoprotective role in DN.
Foundation item: Project (30370663) supported by the National Natural Science Foundation of China 相似文献
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Wilk Christopher M.; Gold James M.; McMahon Robert P.; Humber Katherine; Iannone Virginia N.; Buchanan Robert W. 《Canadian Metallurgical Quarterly》2005,19(6):778
Cognitive impairment is well documented in schizophrenia, though some reports have been interpreted to suggest that it is possible to have schizophrenia without neuropsychological impairment. The authors tested this by comparing the neuropsychological profiles of closely matched patients with schizophrenia and healthy comparison participants. Sixty-four patients with schizophrenia and 64 healthy comparison cases, matched to within 3 Full-Scale IQ points, were tested using the Wechsler Adult Intelligence Scale (3rd ed.; D. Wechsler, 1997b) and the Wechsler Memory Scale (3rd ed.; D. Wechsler, 1997c). Neuropsychological profiles for these groups were markedly different, with the group of patients with schizophrenia exhibiting performance deficits in memory and speeded visual processing but superior verbal comprehension and perceptual organization relative to the group of healthy comparison participants matched on Full-Scale IQ. Thus, scoring in the normal range does not preclude neuropsychological abnormality in schizophrenia, confirming that neuropsychological impairment is a core feature of the illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
959.
The main objective of this paper is to design an intelligent controller system based on the concepts of fuzzy logic. This latter will be used to control the power of a nuclear reactor. The principle of this controller is based on rules established from experiments used with a classical controller and from the knowledge and the expertise of the operators of the reactor. This intelligent controller could be used in parallel with the actual system, which is semiautomatic, as a decision aided system to assist the operators in the control room. 相似文献
960.
基于奇异值分解、模糊聚类和粗糙集理论的旋转机械故障诊断 总被引:1,自引:1,他引:1
对含有重复和冲突对象的离散决策表,提出了一种基于粗糙集的规则获取方法,使得获得的规则能够涵盖所有的对象。对连续条件属性值和离散决策属性值的决策表,基于矩阵的奇异值分解、模糊C均值聚类和粗糙集属性约简技术,提出连续属性最佳离散数目确定方法。在上述方法的基础上,进行旋转机械故障诊断的规则获取,获得的诊断规则具有很好的知识归纳能力和知识泛化能力。利用获得的诊断规则进行旋转机械故障诊断,建立了待诊断对象和诊断规则的弹性匹配模式,使得诊断结论的获取取决于不同的诊断要求。 相似文献