首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   80篇
  免费   1篇
  国内免费   3篇
电工技术   6篇
综合类   4篇
化学工业   7篇
金属工艺   3篇
机械仪表   2篇
建筑科学   1篇
矿业工程   1篇
轻工业   7篇
水利工程   1篇
石油天然气   1篇
无线电   5篇
一般工业技术   1篇
冶金工业   21篇
自动化技术   24篇
  2022年   1篇
  2021年   1篇
  2019年   1篇
  2016年   1篇
  2015年   1篇
  2014年   3篇
  2013年   3篇
  2012年   4篇
  2011年   9篇
  2010年   4篇
  2009年   7篇
  2008年   4篇
  2007年   7篇
  2006年   6篇
  2005年   6篇
  2004年   6篇
  2003年   5篇
  2001年   1篇
  2000年   1篇
  1999年   5篇
  1997年   1篇
  1995年   2篇
  1993年   1篇
  1991年   1篇
  1987年   1篇
  1985年   1篇
  1983年   1篇
排序方式: 共有84条查询结果,搜索用时 15 毫秒
71.
Event counting depends on simple, well-learned knowledge but is effortful and error-prone. In 6 experiments, the authors examined event-counting performance, testing a model that suggests that counting is controlled by minimal goal representations coordinated with perceptual events by temporal synchrony. In Experiment 1, they examined self-paced counting with or without delays that disrupted participants' preferred pacing. In subsequent experiments, participants counted computer-paced events occurring at rhythmic or varied intervals, reporting or verifying totals. Several results support the model: Participants counted rhythmic events more accurately, made undetected undercount errors when counting rhythmic events, and made false alarms to undercount or overcount probes presented at different times. These results suggest that intentions that guide fluent counting specify parameters deictically rather than semantically and that error monitoring is implicit. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
首次提出并深入分析研究了一类全数字化技术,与电网电压n倍频或n分频信号同步的基准正弦电路,并给出了关键电路参数设计准则与试验结果,试验结果与理论分析一致。该基准正弦电路具有输出正弦电压与电网电压n倍频或n分频信号同步,THD小,幅值可调且不受电网电压波动的影响,简单实用,价格低廉等优点,在高频交流环节AC/AC变频变换系统和UPS中具有重要应用价值。  相似文献   
73.
具有同时性综合相对测量法的应用   总被引:1,自引:0,他引:1  
介绍并讨论了综合相对测量法在绝缘介损在线监测中的原理、处理过程及其应用。该法在环境因素不变条件下能减少测量扰动,提高准确性和稳定性,得到较好的结果。通过对环境因素变化瞬时性的研究,提出测量同时性观点以解决综合相对测量法在实际测量中存在的误判问题。现场试验表明:采用具有同时性的综合相对测量法能够很好地消除干扰带来的测量误差,准确判断设备运行状态。  相似文献   
74.
Each relationship has its own personality. Almost immediately after a social interaction begins, verbal and nonverbal behaviors become synchronized. Even in asocial contexts, individuals tend to produce utterances that match the grammatical structure of sentences they have recently heard or read. Three projects explore language style matching (LSM) in everyday writing tasks and professional writing. LSM is the relative use of 9 function word categories (e.g., articles, personal pronouns) between any 2 texts. In the first project, 2 samples totaling 1,744 college students answered 4 essay questions written in very different styles. Students automatically matched the language style of the target questions. Overall, the LSM metric was internally consistent and reliable across writing tasks. Women, participants of higher socioeconomic status, and students who earned higher test grades matched with targets more than others did. In the second project, 74 participants completed cliffhanger excerpts from popular fiction. Judges' ratings of excerpt–response similarity were related to content matching but not function word matching, as indexed by LSM. Further, participants were not able to intentionally increase style or content matching. In the final project, an archival study tracked the professional writing and personal correspondence of 3 pairs of famous writers across their relationships. Language matching in poetry and letters reflected fluctuations in the relationships of 3 couples: Sigmund Freud and Carl Jung, Elizabeth Barrett and Robert Browning, and Sylvia Plath and Ted Hughes. Implications for using LSM as an implicit marker of social engagement and influence are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
The study investigated differences in behavior synchrony of dairy cows during the winter confinement period when managed in 1 of 3 out-wintering pad (OWP) systems, or indoors in free-stall housing. There were 2 replicates of each treatment, and observations were carried out on 3 recording occasions in January and February 2006. On each recording occasion, behavior was recorded every 30 min between 0600 and 0130 h the following day (n = 40). The outcomes for measurement were eligible cows lying (ECL), cow comfort index (CCI), and proportion of animals feeding (AF). Autocorrelation as an indicator of synchrony was calculated using the Durban-Watson statistic and compared across treatments. A centered moving average was calculated, used to obtain the residual, and compared between treatments. Low autocorrelations were recorded in free stalls (39.6 ± 0.1%), indicating lower temporal behavioral synchrony than in the 3 OWP designs. Overall, the greatest proportion of ECL, CCI, and AF occurred in free stalls (60%). However, high proportions (>90%) of ECL were recorded on OWP in the early morning, whereas the range of ECL in free stalls (22 to 87%) was lower. The low overall proportions for ECL (44, 52, and 54%) and CCI (48, 55, and 58%) in the OWP were caused by the cows standing without feeding during daylight hours. Nevertheless, these cows performed more synchronized lying at night, and their behavior was more highly autocorrelated (65.9 ± 0.1, 73.3 ± 0.1, and 52.3 ± 0.1%) than cows in free stalls. Synchrony of behavior is part of the normal behavior repertoire of herd-living animals such as dairy cattle, and OWP may promote a more natural circadian behavior pattern than do free-stall systems. It is important that indices such as CCI and ECL are utilized at appropriate times of the day, when cows are expected to lie; that is, during the evening time. Estimated acceptable levels of these indices may be dependent on the confinement system employed.  相似文献   
76.
Reactive Modules   总被引:4,自引:0,他引:4  
We present a formal model for concurrent systems. The model represents synchronous and asynchronous components in a uniform framework that supports compositional (assume-guarantee) and hierarchical (stepwise-refinement) design and verification. While synchronous models are based on a notion of atomic computation step, and asynchronous models remove that notion by introducing stuttering, our model is based on a flexible notion of what constitutes a computation step: by applying an abstraction operator to a system, arbitrarily many consecutive steps can be collapsed into a single step. The abstraction operator, which may turn an asynchronous system into a synchronous one, allows us to describe systems at various levels of temporal detail. For describing systems at various levels of spatial detail, we use a hiding operator that may turn a synchronous system into an asynchronous one. We illustrate the model with diverse examples from synchronous circuits, asynchronous shared-memory programs, and synchronous message-passing protocols.  相似文献   
77.
Previous studies have shown that menstrual cycle length and fertility are affected by a regular pattern of either: (1) intimate contact with men; or (2) contact with extracts from male axillary secretions; and (3) the axillary extracts of women. Experiments utilizing axillary extracts employed a controlled, double-blind research design using either extract or placebo. The study reported here employed quantitative gas chromatography-mass spectrometry (GC-MS) techniques to determine the concentration of several steroids in the male and female axillary secretion extracts. The steroids examined were: androsterone sulfate, dehydroepiandrosterone sulfate, and the volatile steroid androstenol. The results suggest the following: (1) The concentration of androstenol produced by secretion donors varied during the collection period. Males appear to produce more androstenol at certain times; women's secretions show a menstrual variation in androstenol; the highest concentrations of this compound appear to be produced in the midfollicular phase, prior to ovulation. (2) The concentration of dehydroepiandrosterone sulfate is significantly greater in men than in women. (3) In addition to the steroids, a series of aliphatic acids which range from C2 to C18 in chain length were found. The more volatile members of this series may contribute to the odor of the secretions.  相似文献   
78.
近年来,以家庭融合网络和智能终端为载体,联通网络虚拟社会和现实生活环境,面向家庭提供文化娱乐、生活消费、社区公益等综合服务的数字家庭服务形态成为了焦点。本文重点分析了数字家庭服务中的多屏同步互动应用技术,包括系统总体架构,基于云的平台架构,音频水印、视频水印、音频指纹、视频指纹四种ACR技术以及相关应用业务,并对多屏同步互动应用的趋势和发展进行了探讨,为日后基于自动内容识别技术的多屏同步互动应用实现与改进提供了参考。  相似文献   
79.
The virtual synchrony model for group communication is a powerful paradigm for building distributed applications. Implementations of virtual synchrony usually use failure detectors and failure recovery protocols. In applications that require a large number of groups, significant performance gains can be attained if these groups share the resources required to provide virtual synchrony. A service that maps multiple user groups onto a small number of instances of a virtually synchronous implementation is called a light-weight group service. This paper describes a new design for the light-weight group protocols that enables such service to function transparently. We discuss how these protocols can be applied in dynamic environments, where group mappings cannot be defined a priori and may change over time. We show that it is possible to establish mappings that promote resource sharing and, at the same time, minimize interference. These mappings can be established in an automated manner, using heuristics applied locally at each node. Experiments using an implementation in the Horus system show that significant performance improvements can be achieved with this approach.  相似文献   
80.
基于模糊PID的液压同步控制   总被引:4,自引:0,他引:4  
何清华 《矿山机械》2001,29(2):59-60
提出了一种新的模糊PID和一种改进的主从位置同步系统结构,其仿真结果表明这种利用模糊PID改进的主从位置同步控制方案有着比利用常规数字PID的经典主从位置同步控制方案更好的控制效果。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号