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91.
随着国内外政治、治安局势的不断变化,城市高清网络视频监控系统已经成为公安机关依法履行职能打击违法犯罪的一个重要手段。本文介绍了一种城市高清网络视频监控系统建设方案及技术要求,并以此为框架进行概括总结,系统基本分为前端监控资源采集、监控资源接入、联网集中管理平台、图像资源存储以及图像资源共享平台建设等部分。 相似文献
92.
鉴于冲击水轮机结构上的特殊性,其流量,效率的在线监测目前在国内的实际应用方面还是项空白,本文针对冲击式机级珠具体情况,探讨了基于差理论的监测途径,在此基础上的结合一个冲击式电站的实例,设计出了利用单片机来实现的方案。 相似文献
93.
Marianne Frisén 《Sequential Analysis》2013,32(2):171-193
Abstract After the Shewhart method was suggested for industrial applications, other applications, such as surveillance for bioterrorism and financial transactions, came into focus. Other methods for surveillance have also followed. The relation between the Shewhart method and the followers is examined. A uniform presentation of methods, by expressions of likelihood ratios, facilitates the comparisons between methods. The situations for which the Shewhart method has optimality properties are thus determined. The uses of the Shewhart method and its followers for complicated situations are reviewed. 相似文献
94.
Abstract We discuss the performance of “closed-end” fluctuation tests, used to detect changes in the structural stability of a model, in the case where the time horizon is large and the observations do not possess high enough moments. It is demonstrated via a simulation study that, in the latter case, the choice of the boundary function should take into account the number of moments existing; otherwise the actual size of the test may exceed the nominal level. We suggest an alternative “open-end” fluctuation procedure and study its asymptotic behavior. It turns out that if an improper boundary function is chosen, then the null hypothesis may be rejected even if it is true. This means that an appropriate choice of the boundary function requires some prior information about the tail heaviness of the observations. This is different from the cumulative sum-based monitoring schemes suggested by Chu et al. (1996) and further studied by Horváth et al. (2004). 相似文献
95.
应用智能复合材料修复与智能监测桥梁等基础设施 总被引:1,自引:0,他引:1
简介了一种用于桥梁的新型智能复合材料,可对桥梁同时进行加固和智能监测,并解释其工作原理,展望其应用前景。 相似文献
96.
This study was performed to develop a Real-Time Risk Monitoring System which helps to do fault detection using the information
from plant information systems in a chemical process. In this study, to do fault detection, principal component analysis (PCA)
methods of multivariate statistical analysis were used. The fundamental notions are a set of variable combinations, that is,
detection of principal components which indicate the tendency of variables and operating data. Besides classical statistic
process control, PCA can reduce the dimension of variables with monitoring process. Therefore, they are known as suitable
methods to treat enormous data composed of many dimensions. The developed Real-Time Risk Monitoring System can analyze and
manage the plant information on-line, diagnose causes of abnormality and so prevent major accidents. It’s useful for operators
to treat numerous process faults efficiently. 相似文献
97.
《矿业科学技术学报(英文版)》2021,31(1):91-94
Surface subsidence that results from longwall mining can be large magnitude and can affect significant areas. Conventional methods for subsidence monitoring include leveling, global positioning system(GPS), and photogrammetric surveys. Remote sensing techniques including, aerial LiDAR, terrestrial laser scanning, and satellite-based Differential Interferometric Synthetic Aperture Radar(DInSAR), are also used to measure deformation associated with subsidence. DInSAR data are different than data from conventional subsidence surveys. Images capture data over large areas(hundreds of kilometers), and each pixel(data point) in an image quantifies the average displacement over an area of square meters.DInSAR data can have fairly high time resolution; imaging periods typically range from weeks to months.DInSAR data can be useful to monitor subsidence sequentially over short periods. Regularly monitoring subsidence may help define if caving is progressing normally and can establish relationships between surface deformation and longwall face advance, which has potential to help quantify possible risks to mine stability. In this study, subsidence at a longwall trona mine is monitored over short periods, typically 12 days, as the longwall face is advanced through a panel. C-band interferometric wide swath synthetic aperture radar(SAR) images from the sentinel satellites are used to quantify the subsidence. The onset of subsidence occurs close in time to the beginning of the longwall face advance, and overall,the development of subsidence closely follows the longwall face advance. 相似文献
98.
用热力学法对泵效率,流量进行测定及在线监测的应用研究 总被引:3,自引:0,他引:3
本文结合我国现行的常规法泵测试标准GB3216-89.对泵效率、流量的热力学法测定及在线监测的实际应用进行了综合研究。指出:在现阶段,对电厂锅炉给水泵采用热力学法进行效率、流量测定及在线监测是完全对行的,而对一般工业用泵,则需研制更高精度的测温元件;同时,对测温仪表的精度和可靠性给出了简易、可靠的自样验方法。 相似文献
99.
本文结合我国大型汽轮发电机组轴系扭振在线监测分析系统(简称TSA)的开发研制,概括介绍了目前国内外比较关注的大型汽发机组轴系扭振与监测问题。TSA系统的应用对于机组的扭振事件分析、经济运行与安全保证是非常重要的。 相似文献
100.
Air Quality Monitoring Network Design to Control Nitrogen Dioxide and Ozone,Applied in Granada,Spain
Antonio Lozano José Usero Eva Vanderlinden Juan Raez Juan Contreras Benito Navarrete 《臭氧:科学与工程》2011,33(1):80-89
This paper describes a method to design air quality monitoring networks for nitrogen dioxide and ozone and its application in Granada, a city located in Andalusia, southern Spain. The city has a population of 236,988 inhabitants, and traffic is its main source of air pollution. Sampling campaigns with passive diffusion samplers at 88 sites were carried out to obtain information on the pollution distribution in Granada. The average concentrations found for NO2 and O3 were 36.5 μg/m3 and 51.6 μg/m3, respectively. Maximum values of up to 57.1 μg/m3 NO2 were found in Granada city center and O3 reached 77.2 μg/m3 downwind from the emission source. After spatial interpolation of the obtained values with Geographical Information Systems, a selection of the best locations for the monitoring stations was made, in line with the macro- and microscale siting requirements of the European Directive 2008/50/EC on ambient air quality and cleaner air for Europe. Another sampling campaign with diffusive samplers was carried out in 2007 to determine if the locations of the air quality assessment stations were still representative for their zone. A correction was made in the control network following results of this verification campaign. 相似文献