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   45篇
  免费   0篇
  国内免费   16篇
化学工业   9篇
机械仪表   1篇
能源动力   1篇
轻工业   7篇
石油天然气   5篇
无线电   8篇
一般工业技术   14篇
自动化技术   16篇
  2024年   1篇
  2023年   2篇
  2021年   3篇
  2020年   2篇
  2019年   1篇
  2018年   3篇
  2017年   1篇
  2016年   2篇
  2015年   2篇
  2014年   1篇
  2013年   1篇
  2012年   2篇
  2011年   5篇
  2010年   2篇
  2009年   5篇
  2007年   3篇
  2006年   5篇
  2005年   3篇
  2004年   1篇
  2003年   4篇
  2002年   1篇
  2001年   1篇
  2000年   2篇
  1999年   2篇
  1998年   3篇
  1996年   2篇
  1994年   1篇
排序方式: 共有61条查询结果,搜索用时 31 毫秒
1.
The convexity and continuity of fuzzy mappings are defined through a linear ordering and a metric on the set of fuzzy numbers. The local-global minimum property of real-valued convex functions is extended to convex fuzzy mappings. It is proved that a strict local minimizer of a quasiconvex fuzzy mapping is also a strict global minimizer. Characterizations for convex fuzzy mappings and quasiconvex fuzzy mappings are given. In addition, the Weirstrass theorem is extended from real-valued functions to fuzzy mappings.  相似文献   
2.
Online social platform, such as Wikipedia and Foursquare, has been increasingly exploded due to not only various useful services provided but also social gaming mechanisms that can keep users actively engaged. For example, users are awarded ”virtual goods” like badges and points when they contribute to the community in the network by voluntarily sharing ideas and other information. In this paper, we aim to examine the effectiveness of a social gamification mechanism, named user scores, designed in Foursquare which is one of most popular location-based social networks. A user’s score in Foursquare is an aggregate measure based on recent check-in activities of the user, which reflects a snapshot summary of the user’s temporal and spatial behaviors. Whenever a user checks in to a venue, a list of scores of the user’s friends are visible to the user via a ”leaderboard” which ranks these users’ scores in a descending order. Given a pair of friends who participate in a score competition in such a gimification mechanism, we identify if one user’s scores have significant influence on the other user’s scores by utilizing the Granger Causality Test. To understand what types of users and what types of friends tend to participate in the score competition (i.e., their check-ins are more likely driven by such a gamification mechanism), we extract users’ features (e.g. user’s degree) as well as the features of pairs of friends (e.g., number of common friends, score similarity and ranking difference) to examine whether these features have correlations with those pairs of users who are identified as being involved in the score game. The identified influence on user scores has the important implication on applications including friend and venue recommendations in location-based social networks.  相似文献   
3.
FacetAtlas: multifaceted visualization for rich text corpora   总被引:1,自引:0,他引:1  
Documents in rich text corpora usually contain multiple facets of information. For example, an article about a specific disease often consists of different facets such as symptom, treatment, cause, diagnosis, prognosis, and prevention. Thus, documents may have different relations based on different facets. Powerful search tools have been developed to help users locate lists of individual documents that are most related to specific keywords. However, there is a lack of effective analysis tools that reveal the multifaceted relations of documents within or cross the document clusters. In this paper, we present FacetAtlas, a multifaceted visualization technique for visually analyzing rich text corpora. FacetAtlas combines search technology with advanced visual analytical tools to convey both global and local patterns simultaneously. We describe several unique aspects of FacetAtlas, including (1) node cliques and multifaceted edges, (2) an optimized density map, and (3) automated opacity pattern enhancement for highlighting visual patterns, (4) interactive context switch between facets. In addition, we demonstrate the power of FacetAtlas through a case study that targets patient education in the health care domain. Our evaluation shows the benefits of this work, especially in support of complex multifaceted data analysis.  相似文献   
4.
Lu  Zhao  Lin  Yu-Ru  Huang  Xiaoxia  Xiong  Naixue  Fang  Zhijun 《Multimedia Tools and Applications》2017,76(8):10855-10879
Multimedia Tools and Applications - Nowadays, microblogging has become popular, with hundreds of millions of short messages being posted and shared every minute on a variety of topics in social...  相似文献   
5.
由于动态测量坐标系的存在, 使得数字笔在不同的握笔姿态下, 引起书写平面内摩擦力的分解不同. 由此本文提出采用书写摩擦力进行在线签名识别. 该方法将摩擦力的方向在直角坐标系内进行特征量表示, 并与三维书写力的大小相结合, 实现概率值和距离测度信度级的融合. 在进行真假签名的判别中, 加入快速剔除的方法, 进行两级判别, 以提高识别效率. 实验结果表明, 基于签名书写力大小和方向特征的融合识别方法互相补充, 相对于单个方法具有更高的识别率, 系统性能得到显著改善.  相似文献   
6.
由于解析法在研究相干光通信的相位补偿等问题中存在困难,采用多层相位屏分步传输的数值仿真方法研究大气湍流对星地相干光通信下行传输的影响。首先建立了卫星地面之间的大气湍流中激光传输的仿真模型,可以实现不同天顶角和不同湍流条件下的光传输仿真计算。然后用其进行地球同步轨道(GEO)卫星下行光通信的数值仿真分析,并通过与理论值的对比来检验算法的可靠性。最后结合二进制相移键控(binary phase shift keying, BPSK)相干激光通信系统的误码率(bit error rate, BER)模型,计算分析了下行激光通信信号的衰落系数和BER。  相似文献   
7.
增效射孔是国内外油田勘探开发普遍使用的一种完井方式,本文主要介绍了石油射孔技术的发展现状,并分析了几种增效射孔技术的优缺点.各种复合射孔技术得到了广泛的应用,但在实际操作中仍然存在不少问题,通过分析我国增效射孔技术与先进水平的差距,提出了增效射孔技术今后发展方向的一些建议,实现油气井较大幅度和较长周期的增产目的.  相似文献   
8.
Approaches that enable innate repair mechanisms hold great potential for tissue repair. Herein, biomaterial-assisted sequestration of small molecules is described to localize pro-regenerative signaling at the injury site. Specifically, a synthetic biomaterial containing boronate molecules is designed to sequester adenosine, a small molecule ubiquitously present in the human body. The biomaterial-assisted sequestration of adenosine leverages the transient surge of extracellular adenosine following injury to prolong local adenosine signaling. It is demonstrated that implantation of the biomaterial patch following injury establishes an in situ stockpile of adenosine, resulting in accelerated healing by promoting both osteoblastogenesis and angiogenesis. The adenosine content within the patch recedes to the physiological level as the tissue regenerates. In addition to sequestering endogenous adenosine, the biomaterial is also able to deliver exogenous adenosine to the site of injury, offering a versatile solution to utilizing adenosine as a potential therapeutic for tissue repair.  相似文献   
9.
Thoracic aortic aneurysm (TAA) formation is a multifactorial process that results in diverse clinical manifestations and drug responses. Identifying the critical factors and their functions in Marfan syndrome (MFS) pathogenesis is important for exploring personalized medicine for MFS. Methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), and methionine synthase reductase (MTRR) polymorphisms have been correlated with TAA severity in MFS patients. However, the detailed relationship between the folate-methionine cycle and MFS pathogenesis remains unclear. Fbn1C1039G/+ mice were reported to be a disease model of MFS. To study the role of the folate-methionine cycle in MFS, Fbn1C1039G/+ mice were treated orally with methionine or vitamin B mixture (VITB), including vitamins B6, B9, and B12, for 20 weeks. VITB reduced the heart rate and circumference of the ascending aorta in Fbn1C1039G/+ mice. Our data showed that the Mtr and Smad4 genes were suppressed in Fbn1C1039G/+ mice, while VITB treatment restored the expression of these genes to normal levels. Additionally, VITB restored canonical transforming-growth factor β (TGF-β) signaling and promoted Loxl1-mediated collagen maturation in aortic media. This study provides a potential method to attenuate the pathogenesis of MFS that may have a synergistic effect with drug treatments for MFS patients.  相似文献   
10.
ABSTRACT:  Among different fish slices used for sashimi preparation, tuna is the most popular and preferable fish type for Taiwanese people. To improve the hygienic quality of fish slices, electrolyzed (EO) water containing 10, 50, and 100 mg/L chlorine, was used in combination with CO gas treatment. Effect of different treatment on aerobic plate count (APC), volatile basic nitrogen (VBN), K value, and Hunter L*, a*, b* values of yellow-fin tuna steak during storage (4 °C and −20 °C) were evaluated. It was found that APC, VBN, and K values increased with storage time for all treatment. Except for K value, APC and VBN of tuna steak treated with the combination of more than 50 mg/L chlorine EO water and CO gas had the lowest value after 8 d of refrigerated storage. Hunter a* value of tuna steak treated with only CO gas was the highest, followed by those treated with EO water and CO gas. These results demonstrated that EO water containing 50 mg/L chlorine combined with CO gas treatment in tuna fish steak would be an effective method for enhancing the hygienic quality and freshness for tuna meat and extending refrigerated storage time. Tuna treated with EO water containing 100 mg/L chlorine and CO gas combination had the lowest APC immediately after treatment and reduced further to below detection limit after 1 mo frozen storage at −20 °C.  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