全文获取类型
收费全文 | 373083篇 |
免费 | 31585篇 |
国内免费 | 22673篇 |
专业分类
电工技术 | 57339篇 |
技术理论 | 28篇 |
综合类 | 39501篇 |
化学工业 | 19409篇 |
金属工艺 | 13881篇 |
机械仪表 | 32244篇 |
建筑科学 | 33881篇 |
矿业工程 | 14873篇 |
能源动力 | 12174篇 |
轻工业 | 8813篇 |
水利工程 | 11469篇 |
石油天然气 | 14057篇 |
武器工业 | 5915篇 |
无线电 | 33806篇 |
一般工业技术 | 19413篇 |
冶金工业 | 13465篇 |
原子能技术 | 3284篇 |
自动化技术 | 93789篇 |
出版年
2024年 | 1125篇 |
2023年 | 3586篇 |
2022年 | 6749篇 |
2021年 | 8562篇 |
2020年 | 9463篇 |
2019年 | 7163篇 |
2018年 | 6438篇 |
2017年 | 9396篇 |
2016年 | 10976篇 |
2015年 | 12729篇 |
2014年 | 24234篇 |
2013年 | 20651篇 |
2012年 | 27569篇 |
2011年 | 29491篇 |
2010年 | 22348篇 |
2009年 | 22553篇 |
2008年 | 22801篇 |
2007年 | 28443篇 |
2006年 | 25483篇 |
2005年 | 22608篇 |
2004年 | 18661篇 |
2003年 | 16663篇 |
2002年 | 13018篇 |
2001年 | 10834篇 |
2000年 | 9085篇 |
1999年 | 7318篇 |
1998年 | 5545篇 |
1997年 | 4730篇 |
1996年 | 3981篇 |
1995年 | 3303篇 |
1994年 | 2771篇 |
1993年 | 1913篇 |
1992年 | 1582篇 |
1991年 | 1171篇 |
1990年 | 913篇 |
1989年 | 791篇 |
1988年 | 562篇 |
1987年 | 334篇 |
1986年 | 224篇 |
1985年 | 240篇 |
1984年 | 250篇 |
1983年 | 201篇 |
1982年 | 181篇 |
1981年 | 128篇 |
1980年 | 97篇 |
1979年 | 92篇 |
1978年 | 70篇 |
1977年 | 66篇 |
1976年 | 28篇 |
1959年 | 32篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
991.
Internet远程监控软件设计 总被引:5,自引:0,他引:5
介绍了Internet远程监控的基本原理和一般实现方法,并提出了IP地址问题的解决方法。 相似文献
992.
993.
994.
高明莉 《电子产品可靠性与环境试验》2007,25(3):38-41
从人员质量意识、产品设计质量、原材料/元器件的控制、人员操作质量、产品评审力度等方面,分析质量管理工作中存在的难点,并提出相应的解决措施. 相似文献
995.
提出山西省东南部水电自供区系统网架构建方案 ,对实施步骤 ,电量供应和平衡、调度通讯以及效益等作了分析和论证 ,对方案的必要性和可行性进行了探讨 ,对以后发展提出了建议 相似文献
996.
Assessing the role of basic control measures, antivirals and vaccine in curtailing pandemic influenza: scenarios for the US, UK and the Netherlands 总被引:1,自引:0,他引:1 下载免费PDF全文
An increasing number of avian flu cases in humans, arising primarily from direct contact with poultry, in several regions of the world have prompted the urgency to develop pandemic preparedness plans worldwide. Leading recommendations in these plans include basic public health control measures for minimizing transmission in hospitals and communities, the use of antiviral drugs and vaccination. This paper presents a mathematical model for the evaluation of the pandemic flu preparedness plans of the United States (US), the United Kingdom (UK) and the Netherlands. The model is used to assess single and combined interventions. Using data from the US, we show that hospital and community transmission control measures alone can be highly effective in reducing the impact of a potential flu pandemic. We further show that while the use of antivirals alone could lead to very significant reductions in the burden of a pandemic, the combination of transmission control measures, antivirals and vaccine gives the most 'optimal' result. However, implementing such an optimal strategy at the onset of a pandemic may not be realistic. Thus, it is important to consider other plausible alternatives. An optimal preparedness plan is largely dependent on the availability of resources; hence, it is country-specific. We show that countries with limited antiviral stockpiles should emphasize their use therapeutically (rather than prophylactically). However, countries with large antiviral stockpiles can achieve greater reductions in disease burden by implementing them both prophylactically and therapeutically. This study promotes alternative strategies that may be feasible and attainable for the US, UK and the Netherlands. It emphasizes the role of hospital and community transmission control measures in addition to the timely administration of antiviral treatment in reducing the burden of a flu pandemic. The latter is consistent with the preparedness plans of the UK and the Netherlands. Our results indicate that for low efficacy and coverage levels of antivirals and vaccine, the use of a vaccine leads to the greatest reduction in morbidity and mortality compared with the singular use of antivirals. However, as these efficacy and coverage levels are increased, the use of antivirals is more effective. 相似文献
997.
通过对中国石油大连石化分公司Ⅱ套蒸馏装置扩能改造的设计实践,总结归纳了在老工艺装置上采用立体传质塔盘等新技术、新设备的应用成果。改造后的标定数据表明,改造后装置处理能力可达5.1Mt/a,常、减压系统主要产品质量满足设计要求,装置能耗在386.94—406.60MJ/t,低于设计值。 相似文献
998.
References: 《计算技术与自动化》2003,22(Z1):54-57
In order to avoid unnecessary damage of electrical equipments and installations,high quality power should be delivered to the end user and strict control on frequency should be made, Therefore, it is important to estimate the power system's harmonic components with higher accuracy. This paper presents a new approach for estimating harmonic component in a power system using secant - fuzzy linear regression method. In this approach the non - sinusoidal voltage or current waveform is written as I linear function. The coefficient of this function is assumed to be fuzzy number with a membership function that has center and spread value. The time dependent quantity is written as Taylor series with two different time dependent quantities. The objective is to use the sample obtained from the transmission line to find the power system harmonic components and frequencies. We used an experimental voltage signal from a sub power station as a numerical test. 相似文献
999.
1000.