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   193篇
  免费   14篇
  国内免费   2篇
电工技术   1篇
化学工业   64篇
机械仪表   2篇
建筑科学   6篇
矿业工程   1篇
能源动力   3篇
轻工业   25篇
石油天然气   1篇
无线电   16篇
一般工业技术   40篇
冶金工业   32篇
自动化技术   18篇
  2022年   6篇
  2021年   10篇
  2020年   6篇
  2019年   5篇
  2018年   6篇
  2017年   11篇
  2016年   8篇
  2015年   6篇
  2014年   14篇
  2013年   11篇
  2012年   10篇
  2011年   16篇
  2010年   10篇
  2009年   6篇
  2008年   6篇
  2007年   6篇
  2006年   7篇
  2005年   4篇
  2004年   4篇
  2003年   3篇
  2001年   2篇
  2000年   3篇
  1999年   4篇
  1998年   9篇
  1997年   8篇
  1996年   5篇
  1995年   3篇
  1993年   4篇
  1990年   1篇
  1989年   1篇
  1987年   3篇
  1986年   2篇
  1985年   4篇
  1983年   1篇
  1982年   1篇
  1980年   1篇
  1976年   1篇
  1970年   1篇
排序方式: 共有209条查询结果,搜索用时 31 毫秒
41.
In this study, Taguchi approach was used to determine the influence of waste composition for the optimization of moisture content (MC) and calorific value (CV) of food waste via bio-drying process. The objective was to reduce MC and increase CV of the bio-dried material. The effect of three different levels of four factors including food (FW), paper (Pa), plastic (Pl) waste, and bulking agent (BA) were studied and optimized. The moisture content of the bio-dried material varied between 8.59 and 50.93%, whereas that of the calorific value was 11–25?MJ/kg. The results revealed optimum configurations for MC and CV as FW1Pa3Pl3BA3 and FW1Pa1Pl3BA1, respectively. Regression analysis revealed MC as a positive function of FW and BA with plastic positively correlated with calorific value. ANOVA analysis indicated that FW had more prominent effect on both MC and CV. The predicted and measured values were very close to each other. Additionally, the results realized in the confirmatory experiments at optimized conditions of CV was found to be higher than the test runs of Taguchi design, suggesting that Taguchi method was very successful in the optimization of bio-drying factors for MC and CV.  相似文献   
42.
The novel functionalities of multiferroic magneto-electric nanocomposites have spawned substantial scope for fast-paced memory devices and sensor applications. Following this, herein we report the development of nanocomposites with soft ferromagnetic MnFe2O4 and ferroelectric BiFeO3 to fabricate a system with engineered multiferroic properties. A modified sol-gel route called Pechini method is demonstrated for the preparation of the (1-x) BiFeO3-x MnFe2O4 (x = 10%, 30%, 50%, 70%) nanocomposites. The crystallographic phase, structure, and morphology are characterized by XRD, FESEM, and HRTEM. The accurate crystallite size and lattice strain are determined by Williamson-Hall plot method and a comparative study with Scherer's equation is carried out. TEM image evidences the interface between BiFeO3 and MnFe2O4 nanoparticles in the composite. The room temperature magnetic response reveals the strong dependence of magnetic saturation, remanent magnetization, and coercivity of the nanocomposites on MnFe2O4 addition. The dielectric response and impedance analysis of the prepared nanocomposites are observed. The electrical performance of the composite is affected by grain, grain boundaries, and oxygen vacancies. The unsaturated P-E loops exhibit the leaky ferroelectric behavior for the nanocomposite. The intrinsic magnetoelectric coupling between ferroelectric BiFeO3 and ferromagnetic MnFe2O4 has been determined by varying Hdc/Hac and its maximum coupling coefficient (α) is found to be 25.39 mV/cmOe for 70% BiFeO3 -30% MnFe2O4 nanocomposite. These distinctive and achievable characteristics of the nanocomposite would enable the designing of magnetic field sensors, spintronic devices, and multiferroic memory devices.  相似文献   
43.
Examined the factor structure and psychometric properties of the Reasons for Living Inventory (RFL; M. M. Linehan et al; see record 1983-20123-001) in a sample of college students with a range of suicidal ideation and behaviors. An exploratory factor analysis of the 48-item RFL extracted 6 factors, similar to those described by Linehan et al. All coefficients alpha and item–subscale correlations were adequate. Additional nonclinical normative data are presented. Multivariate analysis of variance (MANOVA) identified 3 significant discriminant functions for group separation. Correlational analyses provided information about the relationships between the RFL and other self-report measures of suicide risk and general psychopathology. Three RFL subscales were useful in predicting suicide risk and general psychopathology. Limitations and future research issues are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
44.
Blocking Gibbs sampling in very large probabilistic expert systems   总被引:1,自引:0,他引:1  
We introduce a methodology for performing approximate computations in very complex probabilistic systems (e.g. huge pedigrees). Our approach, called blocking Gibbs, combines exact local computations with Gibbs sampling in a way that complements the strengths of both. The methodology is illustrated on a real-world problem involving a heavily inbred pedigreee containing 20 000 individuals. We present results showing that blocking-Gibbs sampling converges much faster than plain Gibbs sampling for very complex problems.  相似文献   
45.
Positive corona glow discharge was studied in a system with cylindrical geometry in air and air-carbon dioxide mixtures at normal temperature and pressure (NTP). A spatially resolved spectroscopy technique was used in an attempt to explain the previously observed anomalous charging of particles traveling through the glow region. The results corroborate the existence of the previously reported anomaly. The apparatus developed for taking the spatially resolved spectra and the methods employed may be of interest in fundamental studies of corona discharge behavior in a practical electrostatic precipitator system.  相似文献   
46.
The decision to outsource applications development and support to a foreign vendor involves not only the myriad issues pertinent to outsourcing in general, but a host of additional risks and challenges unique to firms operating in different legal and cultural environments. Careful assessment of these issues helps determine whether offshore outsourcing will realize its potential to reduce costs, improve software quality, and achieve economies of scale in skills acquisition.  相似文献   
47.
Adu-Gyamfi  Daniel  Zhang  Fengli  Takyi  Augustine 《Wireless Networks》2021,27(2):1477-1490
Wireless Networks - The security and privacy risks of group users are major concerns in opportunistic mobile social network (OMSN) platforms, especially when the users share data publicly in a...  相似文献   
48.
Srinivasan  Sriram  Dickens  Charles  Augustine  Eriq  Farnadi  Golnoosh  Getoor  Lise 《Machine Learning》2022,111(8):2799-2838
Machine Learning - Statistical relational learning (SRL) frameworks are effective at defining probabilistic models over complex relational data. They often use weighted first-order logical rules...  相似文献   
49.
50.
This study interrogates the demand and supply of transport infrastructure and services in peri-urban areas of Sunyani Municipality in Ghana. Structured one-on-one interviews were conducted with 100 households across three peri-urban communities in Sunyani (Abesim-Kyidom, Asuakwaa and Adomako). Findings revealed that a majority of peri-urban households (84%) in the study communities who commute daily to and from the city centre are faced with poor transport infrastructure (e.g. poor conditions of road) and unreliable services (e.g. unregulated public transport). Inadequate investment in transport infrastructure and services by the Ghanaian government, the limited activity locations in peri-urban areas, and the concentration of activity locations at the city centre were identified to be contributing to the poor state of transport infrastructure and services in the case study communities. Policy recommendations to improve the situation are further proffered.  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