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71.
以《生活大爆炸》第十一季为研究对象,从语用预设的视角,运用语用预设的共识性、合适性、可撤销性特征分析该剧日常会话,得出结论:违背语用预设的共识性和合适性,遵循语用预设的可撤销性对于日常会话中幽默的产生至关重要。 相似文献
72.
针对水平井作业工具输送困难的问题,同时在满足钻磨作业的基础上,设计了基于液压伸缩原理的连续管牵引器。为满足井下牵引器对大牵引力、井下适应性、通过性、越障能力的要求,创新提出了自激式液压控制回路(无电缆),来实现牵引器协调控制相关动作,采用一种楔形燕尾滑槽弹性支撑结构,以适应井径变化同时满足障碍通过性,使用SolidWorks三维画图软件、 ADAMS(automatic dynamic analysis of mechanical systems)运动仿真等软件建立连续油管牵引器的虚拟样机,验证其运动性能。结果表明:该牵引器在5~1/_2″套管中能够平稳行进,牵引力最大可达到10 000 N,满足设计标准。 相似文献
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电机产品设计主要包括电崩设计、结构设计、发热冷却设计等方面内容。传统设计依靠数学模型和简化的公式,在设计中引入较多的经验数据.使产品的设计产生较大的误差。在产品开发中引入有限元分析技术,全面的分析产品的各方面性能,优化产品的设计。 相似文献
75.
Big Data: Unleashing information 总被引:2,自引:1,他引:1
James M.TIEN 《系统科学与系统工程学报(英文版)》2013,22(2):127-151
At present,it is projected that about 4 zettabytes(or 10**21 bytes)of digital data are being generated per year by everything from underground physics experiments to retail transactions to security cameras to global positioning systems.In the U.S.,major research programs are being funded to deal with big data in all five sectors(i.e.,services,manufacturing,construction,agriculture and mining)of the economy.Big Data is a term applied to data sets whose size is beyond the ability of available tools to undertake their acquisition,access,analytics and/or application in a reasonable amount of time.Whereas Tien(2003)forewarned about the data rich,information poor(DRIP)problems that have been pervasive since the advent of large-scale data collections or warehouses,the DRIP conundrum has been somewhat mitigated by the Big Data approach which has unleashed information in a manner that can support informed-yet,not necessarily defensible or valid-decisions or choices.Thus,by somewhat overcoming data quality issues with data quantity,data access restrictions with on-demand cloud computing,causative analysis with correlative data analytics,and model-driven with evidence-driven applications,appropriate actions can be undertaken with the obtained information.New acquisition,access,analytics and application technologies are being developed to further Big Data as it is being employed to help resolve the 14 grand challenges(identified by the National Academy of Engineering in 2008),underpin the 10 breakthrough technologies(compiled by the Massachusetts Institute of Technology in 2013)and support the Third Industrial Revolution of mass customization. 相似文献
76.
笔者设计了一种采用PLC控制的桥堆老化台电气控制系统,具体论述了桥堆老化台进行电气控制的原理及主要特点,介绍了以微处理器为核心的可编程控制器来实现系统的工作流程控制、采样分析、数据处理、自动巡检、报警等功能。控制系统实现了触摸屏人机对话、自动巡检次品并报警的功能,可调直流电源参数对桥堆正向老化所需要的交流电压参数和进行桥堆反向老化所需要的高精度进行自动控制。 相似文献
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Two types of forecasting methods have been receiving increasing attention by electric utility forecasters. The first type, called end-use forecasting, is recognized as an approach which is well suited for forecasting during periods characterized by technological change. The method is straightforward. The stock levels of energy-consuming equipment are forecast, as well as the energy consumption characteristics of the equipment. The final forecast is the product of the stock and usage characteristics. This approach is well suited to forecasting long time periods when technological change, equipment depletion and replacement, and other structural changes are evident. For time periods of shorter duration, these factors are static and variations are more likely to result from shocks to the environment. The shocks influence the usage of the equipment. A second forecasting approach using time-series analysis has been demonstrated to be superior for these applications. This paper discusses the integration of the two methods into a unified system. The result is a time-series model whose parameter effects become dynamic in character. An example of the models being used at the Georgia Power Company is presented. It is demonstrated that a time-series model which incorporates end-use stock and usage information is superior—even in short-term forecasting situations—to a similar time-series model which excludes the information. 相似文献
79.
为了进一步提高煤矿井下馈电状态传感器的性能,通过对煤矿井下特殊情况、馈电状态传感器的理论探索和现有应用的研究,根据《矿井安全监控新标准、新规程汇编》的要求[1],首次提出一种感应通信式馈电状态传感器,它是根据电压互感器原理和无线通信原理来实现的,从而间接检测矿井电缆的馈电状态,与负载是否工作,电缆有无电流流过无关,只要电缆芯线带电,则输出馈电状态;反之,输出非馈电状态.这种感应通信式馈电状态传感器具有灵敏度高、反映迅速、可靠性高以及维护量少等特点. 相似文献
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