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91.
对火焰的基本特征进行分析,从中选择出几种比较有代表性的火焰特征作为判据来识别和提取火场图像中的火焰区域。基于火灾火焰的亮度特征利用区域生长法分割出疑似火焰区域;根据RGB和HIS颜色模型的对应关系,通过分离火焰像素的R、G、B分量,验证了火焰的色彩分布规律;利用圆形度判据排除规则光源的干扰。  相似文献   
92.
In order to meet the needs of practical design, an interpolation technique is employed to constrain the shape of surfaces. The method of preserving positivity on the interpolation surface and constraint on interpolating data is also developed. The advantage of this new method is that it can be used to constrain the shape of an interpolating surface only by selecting suitable parameters, and numerical examples are presented to show the performance of the method.  相似文献   
93.
There is some debate concerning whether people selectively attend to and remember less negative relative to positive or neutral information with age. We argue that such an age-related negativity reduction effect may be attenuated among individuals who are more interdependent, as they are likely to perceive negative information as equally useful and important as positive information. In 2 studies, we tested this hypothesis by examining memory for (Study 1) and visual attention to (Study 2) emotional (positive vs. negative) stimuli among younger, middle-aged, and older Chinese participants. Findings revealed that the age-related negativity reduction effect was found to a lesser extent among older Chinese individuals who were more interdependent than among those who were less interdependent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
The relationship between sign and stability of equilibria in positive linear systems is investigated in this paper. In particular it is proved that the well-known result “stability and irreducibility imply strict positivity” can be better specified by introducing the notion of excitability. In fact stability, excitability and strict positivity of the equilibria are three perfectly balanced properties since any one of them is implied by the two others.  相似文献   
95.
目的 GC-FPD检测西兰花中氧化乐果疑似阳性,联合GC-MS对检测结果进行确证。方法气相色谱条件完全相同,分别采用HP-1、DB-5和DB-1701,极性不同但规格相同(30 m×0.25 mm×0.25μm,Agilent公司)的3种色谱柱检测氧化乐果,对其保留时间的影响及原理的不同进行了讨论。结果在氧化乐果的出峰位置有一个比较大的峰,与其同时流出的物质确定为干扰物质。结论联合GC-MS进行验证,使检测方法多样化,能有效判断阳性结果真伪。  相似文献   
96.
云计算环境下入侵疑似边界问题改进算法   总被引:1,自引:0,他引:1  
传统的疑似边界问题处理算法一直存在边界确定结果不准确、误差较大的问题,为了提高网络安全性能,提出一种基于模糊网络阈值计算的云计算环境下入侵检测中疑似边界确定算法,分析了云计算环境下入侵种类及其检测原理,并确定其入侵形式;通过计算模糊网络阈值,确定云计算环境下入侵检测中疑似边界具体参数.仿真实验结果表明,采用改进算法进行疑似边界的确定,其结果精度及效率均优于传统算法,具有一定的优势.  相似文献   
97.
利用双二次Bezier曲面为非负的充要条件,给出了分别位于两张双二次NURBS曲面上的点是否为这两张曲面间距离最近的点的判别方法.曲面非负是指在此显式曲面上没有位于XOY平面下方的点.在这一基础上,得到了计算双二次NURBS曲面间最短距离的一个算法.最后,给出了实验结果并将文中算法与采用分层数据结构的常用算法进行了比较。  相似文献   
98.
Research suggests a positivity effect in older adults' memory for emotional material, but the evidence from the attentional domain is mixed. The present study combined 2 methodologies for studying preferences in visual attention, eye tracking, and dot-probe, as younger and older adults viewed synthetic emotional faces. Eye tracking most consistently revealed a positivity effect in older adults' attention, so that older adults showed preferential looking toward happy faces and away from sad faces. Dot-probe results were less robust, but in the same direction. Methodological and theoretical implications for the study of socioemotional aging are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
Reports an error in the original article by D. M. Isaacowitz et al (Psychology and Aging, 2006[March], Vol 21[1], 40-48). Because of a printer's error, an incorrect version of Figure 2 appeared in the article. The correct version of the figure is provided. (The following abstract of this article originally appeared in record 2006-03906-005.) Recent studies have suggested that older individuals selectively forget negative information. However, findings on a positivity effect in the attention of older adults have been more mixed. In the current study, eye tracking was used to record visual fixation in nearly real-time to investigate whether older individuals show a positivity effect in their visual attention to emotional information. Young and old individuals (N = 64) viewed pairs of synthetic faces that included the same face in a nonemotional expression and in 1 of 4 emotional expressions (happiness, sadness, anger, or fear). Gaze patterns were recorded as individuals viewed the face pairs. Older adults showed an attentional preference toward happy faces and away from angry ones; the only preference shown by young adults was toward afraid faces. The age groups were not different in overall cognitive functioning, suggesting that these attentional differences are specific and motivated rather than due to general cognitive change with age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Previous binocular rivalry studies with younger adults have shown that emotional stimuli dominate perception over neutral stimuli. Here we investigated the effects of age on patterns of emotional dominance during binocular rivalry. Participants performed a face/house rivalry task where the emotion of the face (happy, angry, neutral) and orientation (upright, inverted) of the face and house stimuli were varied systematically. Age differences were found with younger adults showing a general emotionality effect (happy and angry faces were more dominant than neutral faces) and older adults showing inhibition of anger (neutral faces were more dominant than angry faces) and positivity effects (happy faces were more dominant than both angry and neutral faces). Age differences in dominance patterns were reflected by slower rivalry rates for both happy and angry compared to neutral face/house pairs in younger adults, and slower rivalry rates for happy compared to both angry and neutral face/house pairs in older adults. Importantly, these patterns of emotional dominance and slower rivalry rates for emotional-face/house pairs disappeared when the stimuli were inverted. This suggests that emotional valence, and not low-level image features, were responsible for the emotional bias in both age groups. Given that binocular rivalry has a limited role for voluntary control, the findings imply that anger suppression and positivity effects in older adults may extend to more automatic tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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