全文获取类型
收费全文 | 1635篇 |
免费 | 173篇 |
国内免费 | 77篇 |
专业分类
电工技术 | 62篇 |
技术理论 | 1篇 |
综合类 | 92篇 |
化学工业 | 61篇 |
金属工艺 | 11篇 |
机械仪表 | 44篇 |
建筑科学 | 702篇 |
矿业工程 | 32篇 |
能源动力 | 32篇 |
轻工业 | 8篇 |
水利工程 | 37篇 |
石油天然气 | 29篇 |
武器工业 | 11篇 |
无线电 | 84篇 |
一般工业技术 | 123篇 |
冶金工业 | 26篇 |
原子能技术 | 131篇 |
自动化技术 | 399篇 |
出版年
2024年 | 3篇 |
2023年 | 15篇 |
2022年 | 51篇 |
2021年 | 70篇 |
2020年 | 98篇 |
2019年 | 35篇 |
2018年 | 23篇 |
2017年 | 46篇 |
2016年 | 56篇 |
2015年 | 65篇 |
2014年 | 179篇 |
2013年 | 116篇 |
2012年 | 168篇 |
2011年 | 178篇 |
2010年 | 125篇 |
2009年 | 84篇 |
2008年 | 87篇 |
2007年 | 112篇 |
2006年 | 88篇 |
2005年 | 46篇 |
2004年 | 53篇 |
2003年 | 43篇 |
2002年 | 26篇 |
2001年 | 26篇 |
2000年 | 14篇 |
1999年 | 22篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 2篇 |
1993年 | 8篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 9篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
排序方式: 共有1885条查询结果,搜索用时 0 毫秒
1.
为确保特殊时期党政军指挥通信畅通,充分利用中国移动现网资源,将卫星通信与地面光缆、微波传榆。以及移动网络无缝衔接,共同构建中国移动天地一体应急通信平台。 相似文献
2.
3.
各国核电厂场外应急计划的比较 总被引:1,自引:0,他引:1
本文分析和比较了各国核电厂的应急计划,特别是场外应急的干予水平和应急计划区,讨论了我国干予水平、核电厂应急计划区和香港核应急计划几个实际问题。 相似文献
4.
Kai Kang 《Fire Technology》2007,43(4):331-346
This paper presents an emergency evacuation analysis during a mid-platform train fire in an underground rail station. A time-based
evacuation scenario is developed taking into account the stairway inaccessibility due to smoke blockage. The calculation approach
in NFPA 130 is then applied to a parametric study of this time-based scenario and its reliability is examined using a micro-simulation
model. Both methods give consistent predictions of the exiting times. The results demonstrate that with the division of the
station into two zones, the exiting time could not meet the code requirements, whereas it does meet the required exiting time
without the division. Such division is due to smoke blockage and creates an uneven ratio of the occupant load to the available
exiting capacity. This shows that appropriate consideration of the fire and smoke effects is important for station egress
evaluation. Other issues such as the fire growth rate and the pre-evacuation time are also discussed. 相似文献
5.
Scheduling emergency medicine residents (EMRs) is a complex task, which considers a large number of rules (often conflicting) related to various aspects such as limits on the number of consecutive work hours, number of day and night shifts that should be worked by each resident, resident staffing requirements according to seniority levels for the day and night shifts, restrictions on the number of consecutive day and night shifts assigned, vacation periods, weekend off requests, and fair distribution of responsibilities among the residents. Emergency rooms (ERs) are stressful workplaces, and in addition shift work is well-known to be more demanding than regular daytime work. For this reason, preparing schedules that suit the working rules for EMRs is especially important for reducing the negative impact on shift workers physiologically, psychologically, and socially. In this paper, we present a goal programming (GP) model that accommodates both hard and soft constraints for a monthly planning horizon. The hard constraints should be adhered to strictly, whereas the soft constraints can be violated when necessary. The relative importance values of the soft constraints have been computed by the analytical hierarchy process (AHP), which are used as coefficients of the deviations from the soft constraints in the objective function. The model has been tested in the ER of a major local university hospital. The main conclusions of the study are that problems of realistic size can be solved quickly and the generated schedules have very high qualities compared to the manually prepared schedules, which require a lot of effort and time from the chief resident who is responsible for this duty. 相似文献
6.
在压水堆核电站应急计划和应急响应中,堆底熔穿事故占有重要位置。本文用法国核电厂事故源项S3(对应于堆底熔穿事故)计算了在典型气象条件下的场外放射学的后果,根据一般防护决策原则和我国颁布的干预水平,提出了保护公众的应急防护措施的建议。 相似文献
7.
目前,在各地均有商贸活动开展,且参与人员众多,如果公安机关事先未做好预案,一旦发生突发性事件,人员疏散不到位,极易造成群死群伤事件。文章以商品大集为例,构建参与人员的流动模型,利用计算机技术实现流量和流动状况的模拟仿真,获得接近实际的流动的时间和动态过程.利于事先对类似活动拥堵情况进行准确评估。 相似文献
8.
Fatah Chetouane Kash Barker Andrea S. Viacaba Oropeza 《Simulation Modelling Practice and Theory》2012,20(1):99-111
An increasing concern of decision makers when dealing with system design is preparation for a wide range of potentially uncertain operating conditions. This paper provides a novel multiobjective approach for simulation-driven decision making that accounts for not only the conventional average system performance indices, but also (i) upper-tail, or extreme, values of these indices, and (ii) measures of their sensitivity to uncertainty in model parameters. The proposed approach is applied to a hospital emergency department service design case study wherein different design alternatives are compared using total time-in-system performance metric under multiple uncertain operating conditions. 相似文献
9.
《Expert systems with applications》2014,41(6):2947-2956
To enable the immediate and efficient dispatch of relief to victims of disaster, this study proposes a greedy-search-based, multi-objective, genetic algorithm capable of regulating the distribution of available resources and automatically generating a variety of feasible emergency logistics schedules for decision-makers. The proposed algorithm dynamically adjusts distribution schedules from various supply points according to the requirements at demand points in order to minimize unsatisfied demand for resources, time to delivery, and transportation costs. The proposed algorithm was applied to the case of the Chi–Chi earthquake in Taiwan to verify its performance. Simulation results demonstrate that under conditions of a limited/unlimited number of available vehicles, the proposed algorithm outperforms the MOGA and standard greedy algorithm in ‘time to delivery’ by an average of 63.57% and 46.15%, respectively, based on 10,000 iterations. 相似文献
10.
Many paramedics' work accidents are related to physical aspects of the job, and the most affected body part is the low back. This study documents the trunk motion exposure of paramedics on the job. Nine paramedics were observed over 12 shifts (120 h). Trunk postures were recorded with the computer-assisted CUELA measurement system worn on the back like a knapsack. Average duration of an emergency call was 23.5 min. Sagittal trunk flexion of >40° and twisting rotation of >24° were observed in 21% and 17% of time-sampled postures. Medical care on the scene (44% of total time) involved prolonged flexed and twisted postures (∼10 s). The highest extreme sagittal trunk flexion (63°) and twisting rotation (40°) were observed during lifting activities, which lasted 2% of the total time. Paramedics adopted trunk motions that may significantly increase the risk of low back disorders during medical care and patient-handling activities. 相似文献