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水电厂气象水文综合预报调度模型整合了降雨预报方案、中长期水文预报方案、洪水预报方案、水库优化调度方案等现有模型系统。降雨数值预报接入水库预报调度系统后,延长了来水预报预见期,结合文中研究的优化调度模型,使水电厂能够提前调整发电计划、调度方案,增加了水电厂的发电效益和水库的防洪减灾社会效益。 相似文献
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Importance of weather monitoring for agricultural decision‐making – an exploratory behavioral study for Oklahoma Mesonet
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Jadwiga R Ziolkowska Jesus Zubillaga 《Journal of the science of food and agriculture》2018,98(13):4945-4954
BACKGROUND
The Oklahoma Mesonet (the statewide environmental and weather monitoring network) has monitored changes in weather patterns since 1994 to provide accurate and timely mesoscale weather information to farmers and other groups. Studies are still scarce that would quantitatively assess farmers' perceptions about the value of the Oklahoma Mesonet contributions to agricultural operations, profitability of land management, and decision making. This paper aims to analyze those questions by means of an exploratory empirical study in Oklahoma for two groups of Mesonet users and non‐users.RESULTS
Familiarity with and application of Mesonet information determines farmers' profitability assessments and decision making. Farmers' perceptions are also influenced by the degree of previous exposure to weather‐related losses. The median estimate of the economic value of Mesonet information is $1000 per year. Mesonet users perceive higher profitability from the application of Mesonet data at 7.6/10, whereas Mesonet non‐users provided an average assessment of 2.6/10.CONCLUSIONS
Consistent use of Mesonet information results in a higher assessment of the importance of Mesonet. This research provides some initial insights into farmers' perceptions about the value of Oklahoma Mesonet information, which could guide stakeholders in developing measures to better serve farmers with environmental monitoring data for improved farm decisions. © 2018 Society of Chemical Industry 相似文献996.
Assessment of offshore wind farm characteristics with the cloud resolving storm simulator: A case study in Japan
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Fredrik Raak Yoshihiko Susuki Kazuhisa Tsuboki Masaya Kato Shinya Eguchi Takashi Hikihara 《风能》2018,21(7):531-543
Wind conditions and output power characteristics of a wind farm in Japan are evaluated with highly resolved weather predictions from the so‐called cloud resolving storm simulator. One year of 30‐hour‐ahead predictions with 2‐km spatial resolution and 1‐hour time resolution are evaluated against 10‐minute averaged measurements (averaged to hourly data) from the wind farm. Also, extremely detailed shorter‐term predictions with 200‐m spatial resolution and 1‐second time resolution are evaluated against 1‐Hz measurements. For the hourly data, wind speeds are predicted with an RMSE of 3.0 to 3.5 m/s, and wind power with about 0.3 per unit. Wind direction is predicted with a standard deviation of errors of 16° to 28° for hourly data, and generally below 10° for the 1‐Hz data. We show that wind power variability—here in terms of increments—can be assessed on the timescale of several hours. The measured and predicted wind spectra are found similar on both short and long timescales. 相似文献
997.
Operation and maintenance is one of the main cost drivers of modern wind farms and has become an emerging field of research over the past years. Understanding the failure behaviour of wind turbines (WTs) can significantly enhance operation and maintenance processes and is essential for developing reliability and strategic maintenance models. Previous research has shown that especially the environmental conditions, to which the turbines are exposed to, affect their reliability drastically. This paper compares several advanced modelling techniques and proposes a novel approach to model WT system and component failures based on the site‐specific weather conditions. Furthermore, to avoid common problems in failure modelling, procedures for variable selection and complexity reduction are discussed and incorporated. This is applied to a big failure database comprised of 11 wind farms and 383 turbines. The results show that the model performs very well in several situations such as modelling general WT failures as well as failures of specific components. The latter is exemplified using gearbox failures. 相似文献
998.
灾害天气会导致电力通信系统的可靠性降低, 警报信息在通信过程中发生畸变的可能性上升, 进而增加对停电区域内元件准确识别故障的困难。现有研究表明, 通过对线路发生故障期间的外部环境数据进行分析可得到该线路的故障风险程度, 但此信息尚很少被用于故障诊断之中。在此背景下,提出一种利用外部天气环境信息进行故障特征匹配的电力系统故障诊断方法。首先, 利用故障期间采集得到的外部环境信息根据灰色模糊理论得到线路综合故障概率。然后, 在现有的电力系统故障诊断解析模型(优化模型)的目标函数中增加外部环境故障特征匹配指标, 对与灾害天气相关故障特征不匹配的故障假说进行惩罚。接着, 利用模拟退火遗传算法对改进的解析模型进行求解。最后, 针对广州市局部电网的故障案例进行仿真测试,结果表明所提的改进故障诊断方法对通信故障的容错性强;此外,还比较分析了考虑与不考虑外部天气环境影响时的诊断结果及差异原因。 相似文献
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Numerical weather prediction models play an important role in the field of wind energy, for example, in power forecasting, resource assessment, wind farm (wake) simulations, and load assessment. Continuous evaluation of their performance is crucial for successful operations and further understanding of meteorology for wind energy purposes. However, extensive offshore observations are rarely available. In this paper, we use unique met mast and Lidar observations up to 315 m from met mast “IJmuiden,” located in the North Sea 85 km off the Dutch coast, to evaluate the representation of wind and other relevant variables in three mainstream meteorological models: ECMWF‐IFS, HARMONIE‐AROME, and WRF‐ARW, for a wide range of weather conditions. Overall performance for hub‐height wind speed is found to be comparable between the models, with a systematic wind speed bias <0.5 m/s and random wind speed errors (centered RMSE) <2 m/s. However, the model performance differs considerably between cases, with better performance for strong wind regimes and well‐mixed wind and potential temperature profiles. Conditions characterized by moderate wind speeds combined with stable stratification, which typically produce substantial wind shear and power fluctuations, lead to the largest misrepresentations in all models. 相似文献
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ZQZ—A型区域自动气象站GPRS通讯模块故障特征分析 总被引:3,自引:0,他引:3
本文就ZQZ—A型区域自动气象观测站GPRS通讯模块的原理、故障特征及通讯过程中出现的故障现象等几个方面进行浅显阐述,分析总结了湘潭市。区域自动站通讯模块出现故障的几种现象,以期能够为区域自动气象站的维护人员提供一些帮助,更好地保证区域自动气象站的正常运行。 相似文献