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21.
This article is the fourth of a series of articles discussing various open research problems in automated reasoning. The problem proposed for research focuses on finding criteria that would enable an automated reasoning program to expand or contract definitions wisely. For evaluating a proposed solution to this research problem, we include suggestions concerning possible test problems.This work was supported by the Applied Mathematical Sciences subprogram of the Office of Energy Research, U.S. Department of Energy, under contract W-31-109-Eng-38.  相似文献   
22.
刘晓东  孙圣和 《微电子学》2002,32(1):34-36,45
文章介绍了一种采用基本逻辑门单元的安全测试矢量集生成测试矢量的方法,该方法可以将搜索空间限制在2(n 1)种组合内。它采用故障支配和故障等效的故障传播、回退等技术,建立了一套从局部到全局的测试生成新方法。同时,利用基本门单元安全测试矢量的规律性,可以实现最小的内存容量要求。在一些基准电路的应用实例中,得到了满意的结果。  相似文献   
23.
Recently Fourier Transform Infrared (FTIR) spectroscopic imaging has been used as a tool to detect the changes in cellular composition that may reflect the onset of a disease. This approach has been investigated as a mean of monitoring the change of the biochemical composition of cells and providing a diagnostic tool for various human cancers and other diseases. The discrimination between different types of tissue based upon spectroscopic data is often achieved using various multivariate clustering techniques. However, the number of clusters is a common unknown feature for the clustering methods, such as hierarchical cluster analysis, k-means and fuzzy c-means. In this study, we apply a FCM based clustering algorithm to obtain the best number of clusters as given by the minimum validity index value. This often results in an excessive number of clusters being created due to the complexity of this biochemical system. A novel method to automatically merge clusters was developed to try to address this problem. Three lymph node tissue sections were examined to evaluate our new method. These results showed that this approach can merge the clusters which have similar biochemistry. Consequently, the overall algorithm automatically identifies clusters that accurately match the main tissue types that are independently determined by the clinician.  相似文献   
24.
本文介绍HART协议物理层设备的测试要求、测试设备、测试方法及测试时的一些特别说明。  相似文献   
25.
A new image analysis technique has been developed which allows maceral analysis of coal to be carried out. The technique is able to separate the liptinite component from the background resin by using two separate images of the surface captured with different camera exposure times. At normal exposure, the liptinite has a similar grey scale value to the surrounding resin, but at a higher exposure time, the resin remains black whilst the liptinite grey scale increases significantly enough to distinguish it from the resin. The method has been tested for repeatability and reproducibility and found to be within the ISO Standard requirements.  相似文献   
26.
Hemispheric involvement in reasoning abilities has been debated for some time, and it remains unclear whether the right hemisphere's involvement in problem solving is modality specific or dependent on the type of spatial reasoning required. In the current study, 2 types of nonverbal reasoning abilities were examined, spatial reasoning and proportional reasoning, in 109 patients with cerebrovascular disease that was confined to either the right or the left hemisphere or was diffuse in nature. Results indicated that no lateralizing effects were present based on type of spatial reasoning. Findings are consistent with the suggestion that higher order cognitive processes involved in nonverbal abstraction and problem solving are not strongly lateralized to the right hemisphere but rather are more generally distributed throughout the cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
岩心PI值试验研究及应用   总被引:5,自引:0,他引:5  
主要论述了在多功能采油化学用剂评价仪上进行的岩心PI值试验的步骤,现象及结论。重点考察了岩心PI值与渗透率、流量及注入截面面积的关系;平行管岩心复合PI值和其中单管岩心PI值的关系。  相似文献   
28.
For the precise determination of the sizes of submicron beam spots test structures with an excellent edge definition are required. For this purpose a semiconductor heterostructure consisting of an 1.62 μm GaInP epi-layer grown on (0 0 1) GaAs has been made, which provides atomically sharp edges for beam spot size measurements. Since the sample has been thinned down by standard transmission electron microscope (TEM) preparation techniques, it can be used for both PIXE and STIM. The sample has been investigated with a TEM and the ion nanoprobe LIPSION. A one-dimensional beam profile in the low current mode was determined by a STIM measurement using 2 MeV protons and yielded a FWHM of (41±4) nm, which is the smallest value reported so far for high energy nuclear micro- and nanoprobes. Furthermore we present nickel nanowhiskers produced at the GSI Darmstadt by electrochemical preparation of etched ion track membranes that have been used to obtain two-dimensional images of the shapes of submicron beam spots. For these measurements a scan over a single nickel nanowhisker having a diameter of 220 nm and a height of about 6 μm was performed.  相似文献   
29.
通过几个典型事例的分析、判断和处理,介绍了该厂怎样利用91l型数采器对2D12—100/8型空压机运行状态进行监测,以预报早期故障,为设备检修提供指导.  相似文献   
30.
多用途放射性废物焚烧系统工程验证试验   总被引:7,自引:4,他引:3  
对建立的多用途放射性废物焚烧系统,进行了工程验证试验。试验主要包括固体废物(包括树脂)和废油焚烧及烟气净化时系统的性能测定、非放示踪试验、72h连续运行考验等。经过共计500多小时的试验,验证了工艺流程、主要设备结构、仪表测控及系统安全等设计的可行性和可靠性;系统运行平稳,设备及仪表工作正常。本系统可一炉多用,其处理能力、减容系数、焚烧灰中残炭率以及系统总去污系数等指标,均达到了设计要求。  相似文献   
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