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51.
52.
One of the most useful geosynthetics in soil reinforcement is geogrid due to its high tensile strength, having a great influence on soil skeleton reinforcement and eventually, increasing bearing capacity of the foundation. In this research, a series of 36 repeated plate load tests have been carried out to investigate the scale effect on geogrid-reinforced soil, tending to further understanding of the behaviour of geogrid-reinforced soil system. Four different soil grains sizes, two different geogrid's aperture sizes (with roughly the same tensile strength) and three different loading plate sizes are the variables considered. During the tests, the applied loading and soil surface settlements were recorded to evaluate the systems' response. As it was expected, the reinforced soil exhibited higher bearing capacity than the unreinforced status, up to 635%. The results show that increasing loading plate size and soils' particle size fortify the response of foundation, especially in reinforced status, against the loading plate penetration. The results further focused on the important role of scale effect on the response of reinforced foundation. It was understood that the optimum nominal aperture size of geogrids should be about 4 times of medium grain size of soil. Also, it was found out that in order to acquisition of highest reinforcement benefits, the footing's width should be in the range 13–25 (20 in average) times of medium grain size of the backfill. Finally, to achieve the best results, it is recommended that the aperture size of geogrids should be selected roughly 0.2 times of footing width. 相似文献
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54.
Email has profoundly influenced the way we communicate personally and professionally and, for many, email negotiations have become a common, every day experience. While many studies have investigated email negotiations by relying on and discussing the characteristics of the medium, this paper focuses on the user’s attitude toward the medium and its respective influence on email negotiation. Specifically, we investigate which dimensions make up negotiators’ attitude toward email, i.e. their email affinity, and how these attitudes, in turn, influence the negotiation outcomes. In our scale development, three facets of email affinity are theoretically considered, empirically explored and validated: email preference, email comfort and email clarity. Our negotiation study contains a quasi-experimental email negotiation exercise where subjects were paired according to their email affinity. Email comfort emerged as a significant predictor of individual profit, joint gain, and different dimensions of subjective value. Theoretical implications and further research are discussed. 相似文献
55.
Facing increasing open innovation trends, Portuguese enterprises are considering the related processes and impacts. Thus, this work aims to identify the sectors whose enterprises most engage in open innovation (such as cooperation on this issue) and which sources/agents are most used. This is analyzed by sector and type of innovation as an interesting way of differentiation for better open innovation strategy delineation. Using the data from the Community Innovation Survey (CIS-2012), it first appraises the nature of the innovation process, either cooperative or firm-based, as the starting level of analysis. Then, it differentiates the results by sector illustrating which cooperation sources/agents are most used (scope) and relative intensity of use (scale). This is important to assess levels of openness and related factors. Results show that main innovating sectors in Portugal are of three types: research-based, knowledge-based and service-based. They reveal an increasing focus on knowledge and services, trends that have been leading to more active openness towards innovation. For instance, health and construction are increasing their openness for innovating and internationalizing processes. However, Portuguese innovation is still more firm-based (in-house) than cooperation-based, especially concerning new products' launching. This work and future analyzes around it can contribute to encourage the open innovation strategy in more sectors of the economy as an easy and effective way to cope with rapid trends and changes. 相似文献
56.
在口服液灯检机杂质检测系统中,口服液瓶体由于履带搓瓶的急停会有轻微的抖动,造成高速工业摄像机拍摄的前后两帧口服液瓶体图像中位于相同空间位置的像素无法重合在一起,导致前后两帧图像做差分结果出现错误。由于口服液中的杂质很小,一般会达到微米级别,因此机械的扰动以及口服液瓶体上的污点都有可能因位置偏差对检测结果造成影响。采用尺度不变特征检测(SIFT)对系统采集的前后两帧图像进行位置配准。SIFT算法稳定性精度很高,适用于高精度口服液杂质检测系统。基于抖动幅度微弱,对该算法进行了一定的改进与简化,以获得最佳配准结果。在实际检测过程中算法稳定,检测结果准确率很高。 相似文献
57.
《Expert systems with applications》2014,41(15):6662-6675
Scale is highly detrimental to surface quality for tinplate products. There are a large number of process variables at a typical hot mill and principal component analysis is a well-known technique for reducing the number of process variables. This paper estimates the principal components associated with the hot mill process variables and puts these through an Adaptive Neuro Fuzzy Inference System (ANFIS) to find those hot mill running conditions that will minimise the amount of scale observed on the bottom of the rolled strip. It was found that the variation observed in all the hot mill process variables could be captured through the use of just six principal components, and that using just three of these in an ANFIS was sufficient to identify those operating conditions leading to coils being produced with a consistently low scale count. Specifically, it was found that the best operating conditions for the hot mill were when the first component was lower than −0.098 the second lower than 0.8058 and the third higher than −0.482. These ranges in turn corresponded to certain hot mill temperatures that depended to some extent on the base chemistry of the incoming slab. 相似文献
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59.
In its current state, the Facebook literature speaks very little about metrics developed specifically for this important social networking service. This study tries to fill part of this gap by conceptualizing, developing and validating a new Facebook use construct, “Gravitating towards Facebook” (GoToFB). Unlike traditional Facebook usage views that have focused on lean usage measures, the one presented in the current study offers a broader conceptualization of the same by taking into account the interaction among three elements: the user, Facebook features, and task. This investigation has put extensive efforts to validate the new Facebook instrument using a series of exploratory and confirmatory scale development techniques and found that it exhibits adequate measurement properties. The resultant scale consists of eight dimensions: connecting, sharing, relaxing, organizing, branding, monitoring, expressing, and learning. The instrument would be useful for businesses looking for deeply understanding how potential customers use Facebook and for researchers seeking to develop and test Facebook success models. 相似文献
60.
《Energy Policy》2016
Increasing energy efficiency is a cornerstone of policy initiatives to tackle climate change and increase corporate sustainability. Convincing people to drive more fuel-efficiently (“eco-driving”) is often an integral part of these approaches, especially in the transport sector. But there is a lack of studies on the long-term persistence and potential interaction of the effects of incentives and training on energy conservation behavior in general and eco-driving behavior in particular. We address this gap with a twelve months long natural field experiment in a logistics company to analyze the time-dependent and potentially interacting effects of rewards and theoretical training for eco-driving on fuel consumption in a real-world setting. We find an immediate reduction of fuel consumption following the introduction of a non-monetary reward and an attenuation of this effect over time. Theoretical eco-driving training shows no effect, neither short-term nor long-term, highlighting the often neglected necessity to include practical training elements. Contrary to common assumptions, the interaction of incentives and theoretical training does not show an additional reduction effect. Our results demonstrate the difficulty of changing engrained behavior and habits, and underline the need for a careful selection and combination of interventions. Policy implications for public and private actors are discussed. 相似文献