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   46篇
  免费   2篇
电工技术   1篇
化学工业   5篇
金属工艺   2篇
机械仪表   1篇
建筑科学   5篇
能源动力   1篇
轻工业   2篇
无线电   8篇
一般工业技术   12篇
冶金工业   5篇
自动化技术   6篇
  2020年   4篇
  2019年   1篇
  2018年   2篇
  2017年   3篇
  2016年   2篇
  2015年   1篇
  2014年   2篇
  2013年   5篇
  2012年   4篇
  2011年   6篇
  2009年   1篇
  2008年   4篇
  2007年   2篇
  2005年   1篇
  2004年   1篇
  1999年   4篇
  1998年   1篇
  1996年   1篇
  1982年   1篇
  1979年   1篇
  1976年   1篇
排序方式: 共有48条查询结果,搜索用时 15 毫秒
21.
A device to provide automated measurement of the electromyographic silent period with real time capability utilizing a voltagetime window is described. This device is being used in the clinical dental diagnosis and treatment of functional disorders of the masticatory system. The design, performance, utilization, and other applications of this device are discussed.  相似文献   
22.
In this paper, the authors introduce multibit all-optical memory devices in nanostructured photonic-crystal circuits using only intrinsic nonresonant optical nonlinearities of semiconductors. Introduced devices can record incoming pulses at speeds of 10 Gb/s using power levels less than 1 mW or at speeds approaching 70 Gb/s using power levels of 10 mW. The incoming pulses are recorded in high-contrast digital output levels independent of the input bit format. The devices exhibit tunable gain for fan-out with negligible reflection and low dissipation and can provide signal regeneration, including reshaping and retiming. Separate signal, clock and reset inputs, and memory outputs coexist without any crosstalk. Input, clock, and output operating frequencies can be independently tuned. By simulating the operation of such all-optical memory devices, it is also shown that nanoscale optical devices can be cascaded to construct densely integrated systems without any isolators or amplifiers, even in the presence of reflections.  相似文献   
23.
24.
25.
ABSTRACT

Football has recently developed into a unique sector with complex management and marketing functions, where novel communication technologies are employed. In this paper, we aim to contribute to the numerous fields involving emerging European sports marketing literature, social media analytics, and digital consumer behaviour. Our purpose is to explore Twitter use related with football by analysing real-time streamed data in offering a longitudinal perspective by focusing on 2013 and 2018 leagues in Turkey via the use of social media analytics framework. Retrieved dataset involved randomly selected publicly available 370 thousand and 6.8 million real-time tweets in 2013 and 2018 leagues, respectively. We report that majority of tweets about the football was posted within the three-hour window before the match independent of the match result and the importance of the result. Moreover, pre-match tweeting volume was almost a crystal ball signalling match winning. Our findings are valuable for sports managers and marketers where some key suggestions provided are to involve particular contexts of winning or losing in their after-match marketing plans, to value weekdays as much as the weekends, and to utilise the after-work prime time of social media engagement.  相似文献   
26.
Using vibration for refining microstructure and improve mechanical properties of aluminium alloys castings are in the interest of researchers for many years. Within the framework of these studies mechanical, ultrasonic and electromagnetic vibration applications were carried out. Results of these processes can be summarized as grain refining and changing the dendritic structure into globular. Accordingly increasing in density and mechanical properties were reported. In this work, orbital shaking technique was used alternatively to conventional mechanical vibration in lost foam casting (LFC) of A380 aluminium alloy. In the experiment castings, effects of shaking movement and speed during pouring were investigated. First of all orbital shaking movement has not damage LFC parts and any shape disorder was not occurred. Optical microstructure observations show that, the increase in shaking speed, decrease secondary dendrite arm spacing (SDAS) and partial dendrite arm fractures were determined at 150 rpm shaking. Density and hardness of as cast specimens were increased with shaking and rising shaking speed as well.  相似文献   
27.
For part I, see ibid., p.143-50. This paper is the second of two companion papers. The foundations of the proposed method of heuristic constraint enforcement on membership functions for knowledge extraction from a fuzzy/neural architecture was given in Part I. Part II develops methods for forming constraint sets using the constraints and techniques for finding acceptable solutions that conform to all available a priori information Moreover, methods of integration of enforcement methods into the training of the fuzzy-neural architecture are discussed. The proposed technique is illustrated on a fuzzy-AND classification problem and a motor fault detection problem. The results indicate that heuristic constraint enforcement on membership functions leads to extraction of heuristically acceptable membership functions in the input and output spaces. Although the method is described on a specific fuzzy/neural architecture, it is applicable to any realization of a fuzzy inference system, including adaptive and/or static fuzzy inference systems  相似文献   
28.
Engineered optical metamaterials present a unique platform for biosensing applications owing to their ability to confine light to nanoscale regions and to their spectral selectivity. Infrared plasmonic metamaterials are especially attractive because their resonant response can be accurately tuned to that of the vibrational modes of the target biomolecules. Here we introduce an infrared plasmonic surface based on a Fano-resonant asymmetric metamaterial exhibiting sharp resonances caused by the interference between subradiant and superradiant plasmonic resonances. Owing to the metamaterial's asymmetry, the frequency of the subradiant resonance can be precisely determined and matched to the molecule's vibrational fingerprints. A multipixel array of Fano-resonant asymmetric metamaterials is used as a platform for multispectral biosensing of nanometre-scale monolayers of recognition proteins and their surface orientation, as well as for detecting chemical binding of target antibodies to recognition proteins.  相似文献   
29.
We consider the problem of detection with side information to model robust signal hashing for content tracking. The receiver observes corrupted (by additive colored Gaussian noise) message signals and performs detection, knowing the noise statistics and only some partial information about the message set, which is obtained via applying a dimensionality- reducing linear transform (represented by a full-rank matrix) to the messages. We derive the optimal GLRT-rule for the binary detection setup and find the corresponding error probability. Next, under some mild assumptions on the message set, we analytically derive the minimax-optimal linear transform matrix that minimizes the worst (over the set of messages) case error probability.  相似文献   
30.
This study evaluated the adhesion of conventional and self-adhesive resin cements to indirect resin composite (IRC) using different surface conditioning methods. Cylindrical IRC specimens (N = 192) were randomly assigned to four surface conditioning methods (n = 8 per group): (a) Control group, (b) Hydrofluoric acid, (c) Tribochemical silica-coating, and (d) 50 μm Al2O3 air-abrasion. Specimen surfaces were finished using silicon carbide papers up to 600 grit under water irrigation, rinsed and dried. Direct composite blocks were bonded to IRC specimens using three conventional resin cements (Multilink, Panavia F2.0, and Resicem) and three self-adhesive resin cements (RelyX U100, Gcem, Speed Cem). Specimens were subjected to shear bond strength test in a Universal Testing Machine (0.5 mm/min). Failure types were categorized as mixed, adhesive and cohesive. Data were analyzed using 2-way ANOVA and Tukey’s tests. Two-parameter Weibull modulus, scale (m) and shape (0) were calculated. The bond strength results (MPa) were significantly affected by the surface conditioning method (p < 0.0001) and cement type (p < 0.001). For Panavia F2.0, Resicem, air-abrasion with 50 μm Al2O3 significantly increased the results (22.6 ± 6.5, 26.2 ± 6.5, respectively) compared to other conditioning methods (13.6 ± 1.4–21.9 ± 3.1) but for Multilink, hydrofluoric acid etching (20.5 ± 3.5) showed significantly higher results (p < 0.01). For the self-adhesive resin cements, air-abrasion with 50 μm Al2O3 significantly increased the results compared to other conditioning methods, except for RelyX U100 (p < 0.05). After air-abrasion with Al2O3, Gcem, (11.64), RelyX U100 (9.05), and SpeedCem (8.29) presented higher Weilbul moduli. Exclusively cohesive failure in the IRC was observed with RelyX U100 and Speedcem after Al2O3 air-abrasion.  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