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《Behaviour & Information Technology》2012,31(2):127-140
This paper reports on an ethnographic field study of 'Out Of This World' (OOTW, Benford et al. 1999) an experiment in 'inhabited television' combining broadcast technologies with a collaborative virtual environment in a live show. The study focuses on the work of producing OOTW and how personnel managed the manifold contingencies of working with complex technology. The use of a specially developed virtual camera control application is discussed together with the methods the director used for live editing views from cameras into a 'broadcast from virtual reality'. The challenges faced by the multiple professions involved (TV personnel, research scientists, actors) are documented and the viability of inhabited TV as a 'new medium' is assessed. Future technological refinements are briefly discussed along with some general implications for CSCW and 'media studies' of the work reported. 相似文献
33.
《Ergonomics》2012,55(7):484-500
The effects of a pressurized suit on human performance were investigated. The suit is known as an Extra-Vehicular Mobility Unit (EMU) and is worn by astronauts while working outside their spacecraft in a low earth orbit. Isolated isokinetic joint torques of three female and three male subjects (all experienced users of the suit in 1G gravity) were measured while working at 100% and 80% of their maximum voluntary torque (MVT, which is synonymous with maximum voluntary contraction (MVC)). It was found that the average decrease in the total amount of work (the sum of the work in each repetition until fatigue) done when the subjects were wearing the EMU were 48% and 41% while working at 100% and 80% MVT, respectively. There is a clear relationship between the MVT and the time and amount of work done until fatigue. Here, the time to fatigue is defined as the ending time of the repetition for which the computed work done during that repetition dropped below 50% of the work done during the first repetition. In general the stronger joints took longer to fatigue and did more work than the weaker joints. It was found that the EMU decreases the work output at the wrist and shoulder joints the most, due to the EMU joint geometry. The EMU also decreased the joint range of motion. The average total amount of work done by the test subjects increased by 5.2% (20.4%) for the unsuited (suited) case, when the test subjects decreased the level of effort from 100% to 80% MVT. Also, the average time to fatigue increased by 9.2% (25.6%) for the unsuited (suited) case, when the test subjects decreased the level of effort from 100% to 80% MVT. It was also found that the experimentally measured torque decay could be predicted by a logarithmic equation. The absolute average errors in the predictions were found to be 18.3% and 18.9% for the unsuited and suited subjects, respectively, when working at 100% MVT, and 22.5% and 18.8% for the unsuited and suited subjects, respectively, when working at 80% MVT. These results could be very useful in the design of future EMU suits and the planning of Extra-Vehicular Activity (EVA) for the future International Space Station assembly operations. 相似文献
34.
张鉴 《安徽工业大学学报》1997,(3)
根据含化合物金属熔体结构的共存理论、相图和Fe-C系亚稳态化合物的有关热力学数据制定了Fe-Si-C熔体的作用浓度计算模型,计算结果符合实际,从而证明所推导的计算模型可以反映本熔体的结构实际.就碳而言,就碳而言,以饱和为标准态的碳作用浓度Nc′可以通过考虑纯物质到饱和标准态的转换系数Lc来求得. 相似文献
35.
1400℃碳溶解度平衡实验测得:锰基Mn-Fe-P-C系碳的溶解度计算式为,Nc=0.2719-0.0940NFe-1.1954Np;整个锰铁熔体浓度范围,即从纯锰到纯铁范围,碳的溶解度计算式有,NC=0.2719-0.0945NFe和Nc==0.1959十0.1044NMn,通过热力学的推导和计算,得到以下一些热力学数据:①铁基体系,锰基体系。 相似文献
36.
Exploring the Role of Transportation in Fostering Social Exclusion: The Use of GIS to Support Qualitative Data 总被引:1,自引:0,他引:1
Travel behavior data collection methodologies have not captured the why of demand nor unsatisfied demand. This has left a gap in the development of methodology that can adequately address the role
that transport plays in fostering social exclusion. This paper presents one innovative technique that utilizes GIS to organize
and analyze data taken from focus groups and the self-mapping of individual space. Implications for transportation planning
include redefining how networks are conceived to include not just road and bus networks, but also the spatio-temporal networks
constructed by low-income people as they organize their activities. 相似文献
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EBSN(Event-based Social Networks)与传统社交网络有所不同,它不仅包含传统社交网中的线上交互(Online Interactions),还包含颇具价值的线下交互(Offline Interactions),是一种异构型复杂社交网络。如何有效利用这种虚拟与物理相融合的交互关系来提高活动推荐服务的质量,是目前学术界和工业界共同关注的热点研究问题之一。传统社交活动推荐算法,如基于用户偏好或线上好友关系的活动推荐算法,除了考虑活动和用户的基本属性外,大多基于显式好友关系EF(Explicit Friendship)进行活动推荐,但EBSN不具备显式好友关系,因此上述算法均不能直接用于EBSN活动推荐。为此,定义了一种新的潜在好友关系LF(Latent Friendship),LF关系将线上同组、线下同活动综合纳入活动评分计算中,以体现LF对EBSN活动推荐的影响;同时,基于此提出了一种基于潜在好友关系的EBSN活动推荐算法(Activity Recommendation Algorithm based on Latent Friendships,ARLF),该算法在寻找潜在好友关系时,创新性地运用元路径思想,使得EBSN中的异构信息得到了充分利用。最后,利用Meetup事件社交网中的真实数据对ARLF算法进行了性能测试,可扩展性实验证明了该算法是可行且有效的。 相似文献
40.
研究目的是揭示长期施肥对棕壤主要酶活性的影响,为土壤培肥以及合理施肥提供理论依据。研究试材采自沈阳农业大学土地与环境学院棕壤肥料长期定位试验微区,共11个施肥处理。结果表明,土壤转化酶、中性磷酸酶、碱性磷酸酶在玉米拔节期及灌浆期出现两个活性高峰,脲酶在玉米拔节期、过氧化氢酶在玉米大喇叭口期各出现一个活性高峰。长期施用有机肥能够提高土壤过氧化氢酶、转化酶及脲酶活性,降低土壤磷酸酶活性,磷肥能够增强土壤过氧化氢酶及转化酶的活性,氮肥则对过氧化氢酶、转化酶、脲酶具有抑制作用。土壤各种酶之间及酶与土壤养分、玉米产量之间存在显著或极显著相关性。因此合理施肥营造良好的土壤生物化学环境将有利于土壤肥力的保持与提高,为作物的高产稳产提供有利保障。 相似文献