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51.
This study proposes a method that uses an artificial neural network (ANN) to mimic human decision-making about route choice in a crowded transportation station. Although ANN models have been developed rapidly and widely adopted in various fields in the last three decades, their application to predict human decision-making in pedestrian flows is limited, because the video clip technology used to collect pedestrian movement data in crowded conditions is still primitive. Data collection must be carried out manually or semi-manually, which requires extensive resources and is time consuming. This study adopts a semi-manual approach to extract data from video clips to capture the route choice behaviour of travellers, and then applies an ANN to mimic such decision-making. A prediction accuracy of 86% (ANN model with ensemble approach) is achieved, which demonstrates the feasibility of applying the ANN approach to decision-making in pedestrian flows. 相似文献
52.
In this paper, we propose a novel methodology to define and estimate a surrogate measure. By imposing a hypothetical disturbance to the leading vehicle, the following vehicle’s action is represented as a probabilistic causal model. After that, a tree is built to describe the eight possible conflict types under the model. The surrogate measure, named Aggregated Crash Index (ACI), is thus proposed to measure the crash risk. This index reflects the accommodability of freeway traffic state to a traffic disturbance. We further apply this measure to evaluate the crash risks in a freeway section of Pacific Motorway, Australia. The results show that the proposed indicator outperforms the three traditional crash surrogate measures (i.e., Time to Collision, Proportion of Stopping Distance, and Crash Potential Index) in representing rear-end crash risks. The applications of this measure are also discussed. 相似文献
53.
R.G. Poulos J. Hatfield C. Rissel L.K. Flack S. Murphy R. Grzebieta A.S. McIntosh 《Accident; analysis and prevention》2015
This paper examines self-reported prospectively collected data from 2038 adult transport and recreational cyclists from New South Wales (Australia) to determine exposure-based incident crash and injury rates. During 25,971 days of cycling, 198 crashes were reported, comprising approximately equal numbers of falls and collisions. The overall crash rate was 0.290 (95% CI, 0.264–0.319) per 1000 km or 6.06 (95% CI, 5.52–6.65) per 1000 h of travel. The rate of crashes causing any injury (self-treated, or medically attended without overnight hospital stay) was 0.148 (95% CI, 0.133–0.164) per 1000 km or 3.09 (95% CI, 2.79-3.43) per 1000 h of travel. The rate of crashes causing a medically attended injury (without overnight hospital stay) was 0.023 (95% CI, 0.020–0.027) per 1000 km or 0.49 (95% CI, 0.43-0.56) per 1000 h of travel. No injuries requiring an overnight stay in hospital were reported on days meeting the inclusion criteria. After adjustment for exposure in hours, or for the risks associated with different infrastructure utilisation, the rates of crashes and medically attended injuries were found to be greater for females than males, less experienced than more experienced cyclists, and for those who rode mainly for transport rather than mainly for recreation. Comparison of estimated crash and injury rates on different infrastructure types were limited by the small number of events, however findings suggest that the separation of cyclists from motorised traffic is by itself not sufficient to ensure safe cycling. 相似文献
54.
作为荷兰紧凑与绿色新城的典范,豪滕的发展模式和经验开始受到越来越多的关注,尤其在气候变化和低碳发展成为全球关注的重点之后.为了全面地展现豪滕的发展经验,文章从豪滕的发展历史、规划理念、空间模式、交通体系、发展绩效等多个方面展开分析.通过豪滕的案例可以看到,好的规划理念与设计是城市绿色及可持续发展的基础,自行车与步行优先以及良好的公共交通体系是绿色城市规划设计的核心,而公共政策与教育对于城市的绿色与可持续发展尤为重要. 相似文献
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结合工程案例,比较、分析超高层建筑变配电所的不同设置方案,及其技术经济性,在充分考虑配电干线长度等因素的同时,应考虑项目全寿命周期内配电干线上的电能损耗;并对单台变压器的容量选择、超高层建筑中的变压器运输进行探讨,建议地上部分变压器单台容量不超过1000 kVA为宜。 相似文献
58.
摘要:空中候梯厅是超高层建筑物电梯输送系统的重要组成部分,本文阐述了构成空中候梯厅的可调节转换台系统、横向移动的往复输送系统,以及穿梭电梯的系统结构、控制设计原理、运行操作技术,以及这些技术的应用,以期更合理地设计出高空电梯输送系统。 相似文献
59.
《Structure and Infrastructure Engineering》2013,9(2):153-156
In 1998, the Texas Department of Transportation (TxDOT) identified two concrete distress mechanisms occurring on its bridge over Lake Ivie in the west central part of the state: alkali – silica reaction (ASR) and delayed ettringite formation (DEF), collectively referred to by TxDOT as premature concrete deterioration (PCD). The agency sponsored two research projects to investigate the problem. One focused on determining the remaining capacity of PCD-damaged concrete members with a case study of the Lake Ivie bridge and the other assessed treatments that could be applied to members with PCD damage. Based on findings of the study, TxDOT applied a system that waterproofed the damaged columns and then confined them using resin-bonded carbon fibre reinforced polymer (CFRP) fabric strips. This paper describes the efforts of TxDOT to mitigate PCD damage for its Lake Ivie bridge. 相似文献
60.
为了提高煤炭资源的采出率、减少资源浪费、改善矿区地表周边环境质量,霍州煤电集团率先提出建筑物下长壁综合机械化采煤黄土充填技术。本文根据黄土充填开采运输系统在建筑物下长壁综合机械化采煤黄土充填技术中的重要性,分析了黄土运输的自然特性,并对黄土充填开采地表至井下重要运输环节一投料井进行了设计及研究。结果表明,黄土充填开采地表至井下运输系统可满足工作面充填开采的需要。 相似文献