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51.
As the world moves toward more green and efficient means of modes of transport, electric vehicles are the most suitable and ideal choice to fulfill this requirement. Rapid developments in the field of battery technology are the main reason for their progress, but thermal management in such systems has been an area of concern for a long time. The work undertaken is to design and develop a battery management system (BMS) with a specific focus on the thermal behavior of the battery pack with varying vehicle loads as well as environmental conditions. To design an efficient BMS, one needs to model the battery behavior covering the thermal as well as electrical aspects of the battery. Apart from the battery model, a mathematical model of the electrical vehicle to mimic the various road load conditions for battery also needs to be modeled. Depending on the need for cooling based on battery behavior, the cooling circuit is modeled for the battery pack used. The entire study has been carried out using Dymola, a mathematical modeling software. 相似文献
52.
In the water distribution network (WDN), although the water demand of the node is changing constantly, the water quantity and water pressure of the node need to be met at each moment. To realize energy saving and consumption reduction, it is proposed to control the nodal water head of WDN in an appropriate narrow range. The frequent large fluctuation of the water demand, which may lead the water pressure exceed the expected range, increases the difficulty of the zone control. To realize optimized WND control, a novel zone predictive control is proposed, where two switching cases are considered. The switching condition is whether there are feasible solutions to keep the pressure within the expected region over the prediction horizon. When the condition is satisfied, the controller minimizes the variation of inputs with constraints of pressure range for ensuring the tank level staying within the expected zone and obtaining optimal economic cost. When the current pressure is out of the expected region or the condition is not satisfied due to the large variation of water demand, a reference trajectory of outputs is introduced, which is combined with the inputs as an optimization variable, and the constraints of expected zone are moved from the output to the introduced reference trajectory. Through minimizing the distance between reference trajectory and output, the controller will keep the tank level from deviating too far from the expected zone and will drive the tank level rapidly into the expected zone once the tank level exceeds the expected range. An application of the proposed zone MPC to WDN in Shinan District of Shanghai is given to illustrate its effectiveness. 相似文献
53.
全自动集装箱码头装卸系统集成了当今世界各项先进技术,在研发、制造、调试过程中,都要坚持质量第一、安全第一的原则,确保各项技术参数可靠,设备运行稳定。在总结国内几个全自动码头装卸系统的质量管理方法与经验的基础上,结合自动化码头自身特点,给出全自动集装箱码头装卸系统主要质量管理方法,进一步丰富发展自动化码头装卸系统建造过程中的“不欠债离岸”质量管理理念。 相似文献
54.
基于SSM框架的大坝监测数据管理系统设计 总被引:1,自引:0,他引:1
针对目前大坝安全监测存在数据不能实时计算分析、展示,长期运行产生的大量数据主要靠人工整编且易出错等问题,结合现代信息化技术手段,以Java作为服务开发语言,设计了基于Spring+SpringMVC+Mybatis(SSM)框架的大坝安全监测数据管理平台,用于大坝监测数据的管理和分析,实现数据采集、存储、查询、计算分析、绘图、生成报表报告、实时监控及远程展示等功能,同时亦为监测仪器管理提供了可视化界面,方便仪器管理。结果表明,基于SSM框架的大坝安全监测数据管理系统实时反馈效果好,操作便捷,数据存取性能好、可视化程度高,便于大坝监测数据的管理与实时分析,为大坝安全运行与决策提供支撑。 相似文献
55.
针对土石坝工程运行期海量监测数据异构、数据整合分析困难、管理效率低下等问题,提出以BIM与GIS融合应用为核心的解决方法,同时搭建运行期物联网感知体系,利用Socket技术,实现监测数据的实时传输。基于此,研发了土石坝工程运行期BIM与GIS融合管控平台,打通了多维业务数据与BIM模型的数据壁垒,实现了数据的对象级管理和整合分析,同时针对数字化移交、监测信息管理、安全分析预警等进行全方位三维可视化管控,促进了土石坝工程运行期的精益管理。实例应用结果表明,BIM与GIS融合管控平台解决了土石坝工程运行期管理过程中可视化程度低、数据信息整合困难的问题,为土石坝工程运行管控提供了一种新方法。 相似文献
56.
综机设备是煤矿采掘生产效率的重要支撑,如果没有先进的综机设备,要想提高采掘生产效率是不可能的。从综机设备集中化和综机设备检修的专业化,分别阐述了其发展趋势,简要总结了中煤新集多年的实践经验,并针对目前管理存在的问题提出相应的建议。 相似文献
57.
《International Journal of Hydrogen Energy》2020,45(53):29110-29122
This paper presents an experimental study of a standalone hybrid microgrid system. The latter is dedicated to remote area applications. The system is a compound that utilizes renewable sources that are Wind Generator (WG), Solar Array (SA), Fuel Cell (FC) and Energy Storage System (ESS) using a battery. The power electronic converters play a very important role in the system; they optimize the control and energy management techniques of the various sources. For wind and solar subsystem, the speed and Single Input Fuzzy Logic (SIFL) controllers are used respectively to harvest the maximum power point tracking (MPPT). To maintain a balance of energy in the hybrid system, an energy management strategy based on the battery state of charge (SOC) has been developed and implemented experimentally. The AC output voltage regulation was achieved using a Proportional Integral (PI) controller to supply a resistive load with constant amplitude and frequency. According to the obtained performances, it was concluded that the proposed system is very promising for potential applications in hybrid renewable energy management systems. 相似文献
58.
《International Journal of Hydrogen Energy》2020,45(1):207-215
We describe the operation of a bench-scale stationary hydrogen energy system comprising photovoltaic (PV) panels, a water electrolyzer (Ely), metal hydride tanks fabricated using an AB-type TiFe-based alloy (TiFe-based tanks), fuel cells (FC), and batteries under various weather conditions. The FC and TiFe-based tanks are thermally coupled to transfer heat when necessary to stabilize the output power, and automatic control is provided via a building energy management system (BEMS), which plans the operating schedule up to 48 h in advance based on the weather forecast and expected demands of the building. Experiments were conducted for 24-h operation on a fine day, 48-h operations on partly cloudy and partly cloudy days, and 48-h operations on partly cloudy and rainy days in order to verify the system. Each operation was performed as planned. Our results show that it is possible to operate the hydrogen system all year round without external heat sources. 相似文献
59.
Serge Nyallang Nyamsi Mykhaylo Lototskyy Ivan Tolj 《International Journal of Hydrogen Energy》2018,43(50):22568-22583
Thermo-chemical energy storage based on metal hydrides has gained tremendous interest in solar heat storage applications such as concentrated solar power systems (CSP) and parabolic troughs. In such systems, two metal hydride beds are connected and operating in an alternative way as energy storage or hydrogen storage. However, the selection of metal hydrides is essential for a smooth operation of these CSP systems in terms of energy storage efficiency and density. In this study, thermal energy storage systems using metal hydrides are modeled and analyzed in detail using first law of thermodynamics. For these purpose, four conventional metal hydrides are selected namely LaNi5, Mg, Mg2Ni and Mg2FeH6. The comparison of performance is made in terms of volumetric energy storage and energy storage efficiency. The effects of operating conditions (temperature, hydrogen pressure and heat transfer fluid mass flow rates) and reactor design on the aforementioned performance metrics are studied and discussed in detail. The preliminary results showed that Mg-based hydrides store energy ranging from 1.3 to 2.4 GJ m?3 while the energy storage can be as low as 30% due to their slow intrinsic kinetics. On the other hand, coupling Mg-based hydrides with LaNi5 allow us to recover heat at a useful temperature above 330 K with low energy density ca.500 MJ m?3 provided suitable operating conditions are selected. The results of this study will be helpful to screen out all potentially viable hydrides materials for heat storage applications. 相似文献
60.