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71.
Due to various geological processes such as tectonic activities fractures might be created in rock mass body which causes creation of blocks with different shapes and sizes in the rock body. Exact understanding of these blocks geometry is an essential issue concerned in different domains of rock engineering such as support system of underground spaces built in jointed rock masses, design of blasting pattern, optimization of fragmentation, determination of cube blocks in quarry mines, blocks stability, etc. The aim of this paper is to develop a computer program to determine geometry of rock mass blocks in two dimensional spaces. In this article, the geometry of jointed rock mass is programmed in MATLAB™.  相似文献   
72.
In this paper, an image edge detection method based on multi-fractal spectrum analysis is presented. The coarse grain H?lder exponent of the image pixels is first computed. then, its multi-fractal spectrum is estimated by the kernel estimation method. Finally, the image edge detection is done by means of different multi-fractal spectrum values. Simulation results show that this method is efficient and has better locality compared with the traditional edge detection methods such as the Sobel method. __________ Translated from Journal of Hunan University (Natural Sciences), 2004, 31(4): 28–33  相似文献   
73.
The use of surface plasmon resonance (SPR) spectroscopy has been applied to a wide variety of fields such as biosensors and surface analysis instruments. In general, a SPR substrate is prepared using self-assembled monolayer (SAM) method of organic molecules as receptor for the target on a layer of gold or silver. However, mesoporous inorganic materials such as SBA-15 have benefits as sensor substrate for SPR. Mesoporous silica has a large surface area which receptor molecule can be attached and has a rigid body which has an excellent stability in the extreme condition compared to organic sensing layer. We prepared an organic modified mesoporous silica and successfully immobilized it on a gold surface, in an attempt to use as a substrate for SPR spectroscopy. For the comparison of sensitivity of prepared substrate, Pt2+ detection was selected as a model system. Substrate prepared in this study exhibited the capability of selective sensing for Pt2+ ions.  相似文献   
74.
支持向量聚类(SVC)是在支持向量机的思想上发展而来一种聚类方法,针对其处理大规模数据集速度缓慢的缺点,提出了一种改进的分块支持向量聚类算法。改进的算法分为三个阶段:前期的预处理,中期的分块算法,后期的改进标类算法。提出的方法显著加快了SVC的速度,在保持原来SVC算法的优点的基础上,对大规模数据集以及非均匀分布数据集等具有良好的效果。将其应用到网络入侵检测,实验结果表明改进的算法行之有效。  相似文献   
75.
一种晶闸管整流器全关断检测电路   总被引:1,自引:0,他引:1  
本文提出并介绍了欧姆逻辑无环流检测的一种方案——晶闸管流器全关断检测,并与软件检测和电流互联器检测进行比较分析,最终得出晶闸管全关断检测方案准确可行的结论。全关断的输出信号与上述两种信号进行综合利用,从而准确可靠地实现了欧姆的逻辑无环流控制。  相似文献   
76.
The ability to remember visual stimuli over a short delay period is limited by the small capacity of visual working memory (VWM). Here the authors investigate the role of learning in enhancing VWM. Participants saw 2 spatial arrays separated by a 1-s interval. The 2 arrays were identical except for 1 location. Participants had to detect the difference. Unknown to the participants, some spatial arrays would repeat once every dozen trials or so for up to 32 repetitions. Spatial VWM performance increased significantly when the same location changed across display repetitions, but not at all when different locations changed from one display repetition to another. The authors suggest that a major role of learning in VWM is to mediate which information gets retained, rather than to directly increase VWM capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
A method of leak detection, based on high-temperature resistant microphones, was originally developed in JNC to detect leakages with flow rates from 1 m3/h to 500m3/h. The development performed on Fugen is focused on detection of a small leakage at an early stage. Specifically, for the inlet feeder pipes the leak rate of 0.2gpm (0.046m3/h) has been chosen as a target detection capability. Evaluation of detection sensitivity was carried out in order to check the capability of the method to satisfy this requirement. The possibility of detecting and locating a small leakage has been demonstrated through the research.  相似文献   
78.
Fuzzy logic for signal prediction in nuclear systems   总被引:2,自引:0,他引:2  
In this paper, we present a fuzzy logic-based algorithm which allows to build a predictive model of an evolving signal. The if-then rules are inferred from the available input-output data. The errors of the model predictions with respect to the measured plant signals can then be used to detect, in real-time, any deviation of the process due either to a component's failure or to an operator's action. Applications of the approach are presented with respect to a chaotic time series of literature and to the water level in the steam generator of a PWR.  相似文献   
79.
新型无机闪烁体CeF3的时间特性研究   总被引:5,自引:0,他引:5  
CeF3是新型快响应无机闪烁体.对近年国内研制的CeF3无机闪烁体的时间特性进行了研究,包括脉冲辐射诊断所关心的CeF3对快脉冲γ辐射源的时间响应.如上升时间、半高竟、脉冲后沿;同时推算并使用了用脉冲法获得晶体发光衰减常数的简单估算公式,获得的CeF3衰减常数值与国外研究同行其它测量方法得到的结果基本一致。  相似文献   
80.
张方 《电气传动》2003,33(3):27-28
文章介绍了现代高层建筑全自动控制系统中,利用主控计算机对检测到的水位信号,监测到的水质信号进行模糊化处理。并通过单片机带动执行机构进行水位调整,以获得节水、节电、节能及保证水质的良好效果。  相似文献   
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