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181.
182.
动力传动系统的设计对于一款新车的研发有着至关重要的作用。针对一种菱形四轮驱动汽车的动力传动系统进行了设计与研究。结合整车动力性评价指标,为提高行驶安全性,用工程分析与仿真校验相结合的方法对动力传动系统的主要部件进行了选型,确定了发动机、电机、主减速器、电池的主要性能参数。最后利用ADVISOR软件对相应工况下的整车动力性能(加速性能、爬坡性能和续驶里程)进行了仿真验证,结果表明所确定的动力系统的参数基本达到了整车动力性的要求,所设计的动力传动系统符合设计要求,为后期的实车研发工作起到了很好的指导作用。 相似文献
183.
本文从矿井操车系统着手,针对矿井操车监控特点设计系统控件,在这些控件的基础上完成上位机软件监控,软件能实时监控系统运行状况,可远程监控,故障智能检测,维护量较小,有一定的推广价值。 相似文献
184.
针对造纸干燥部的工况多变、选用传统控制方式不易控制的情况,设计了一种基于模糊PID算法设计的S7-300控制系统,介绍了理论上和实际组态、编程的实现方法。该系统鲁棒性强,可适应复杂工况,实际应用结果表明该系统算法合理、易实现,控制效果好。 相似文献
185.
门禁控制系统作为安防系统的主要子系统,在各种场所的应用非常广泛。作为安全防护的第一道防线,其安全性尤为重要。本文主要从门禁控制系统管理软件安全、硬件设备安全、工程安全、网络安全及数据安全等各方面进行了探讨与设计。 相似文献
186.
We report here on software that performs line-by-line spectroscopic simulations on gases. Elaborate models (such as narrow band and correlated-K) are accurate and efficient for bands where various components are not simultaneously and significantly active. Line-by-line is probably the most accurate model in the infrared for blends of gases that contain high proportions of H2O and CO2 as this was the case for our prototype simulation. Our implementation on graphics processing units sustains a speedup close to 330 on computation-intensive tasks and 12 on memory intensive tasks compared to implementations on one core of high-end processors. This speedup is due to data parallelism, efficient memory access for specific patterns and some dedicated hardware operators only available in graphics processing units. It is obtained leaving most of processor resources available and it would scale linearly with the number of graphics processing units in parallel machines. Line-by-line simulation coupled with simulation of fluid dynamics was long believed to be economically intractable but our work shows that it could be done with some affordable additional resources compared to what is necessary to perform simulations on fluid dynamics alone.
Program summary
Program title: GPU4RECatalogue identifier: ADZY_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADZY_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 62 776No. of bytes in distributed program, including test data, etc.: 1 513 247Distribution format: tar.gzProgramming language: C++Computer: x86 PCOperating system: Linux, Microsoft Windows. Compilation requires either gcc/g++ under Linux or Visual C++ 2003/2005 and Cygwin under Windows. It has been tested using gcc 4.1.2 under Ubuntu Linux 7.04 and using Visual C++ 2005 with Cygwin 1.5.24 under Windows XP.RAM: 1 gigabyteClassification: 21.2External routines: OpenGL (http://www.opengl.org)Nature of problem: Simulating radiative transfer on high-temperature high-pressure gases.Solution method: Line-by-line Monte-Carlo ray-tracing.Unusual features: Parallel computations are moved to the GPU.Additional comments: nVidia GeForce 7000 or ATI Radeon X1000 series graphics processing unit is required.Running time: A few minutes. 相似文献187.
C. Hermans C. Vanaken T. Mertens F. Van Reeth P. Bekaert 《Computer Graphics Forum》2008,27(2):281-290
Many video sequences consist of a locally dynamic background containing moving foreground subjects. In this paper we propose a novel way of re‐displaying these sequences, by giving the user control over a virtual camera frame. Based on video mosaicing, we first compute a static high quality background panorama. After segmenting and removing the foreground subjects from the original video, the remaining elements are merged into a dynamic background panorama, which seamlessly extends the original video footage. We then re‐display this augmented video by warping and cropping the panorama. The virtual camera can have an enlarged field‐of‐view and a controlled camera motion. Our technique is able to process videos with complex camera motions, reconstructing high quality panoramas without parallax artefacts, visible seams or blurring, while retaining repetitive dynamic elements. 相似文献
188.
The sensitivity and rise time of a transient characteristic of a digital sampling signal converter are experimentally researched. The sampling converter is built at a clocked tunnel-diode comparator. 相似文献
189.
A multi-objective controller synthesis problem is considered in which an output is to be regulated approximately by assuring a bound on the steady-state peak amplification in response to an infinite-energy disturbance, while also guaranteeing a desired level of performance measured in terms of the worst-case energy gain from a finite-energy input to a performance output. Relying on a characterization of the controllers with which almost asymptotic regulation is accomplished, the problem of guaranteeing the desired level of performance is reduced to solving a system of linear matrix inequalities subject to a set of linear equality constraints. Based on the solution of this system, a procedure is outlined for the construction of a suitable controller whose order is equal to the order of the plant plus the order of the exogenous system. 相似文献
190.
control with limited communication and message losses 总被引:2,自引:0,他引:2
We propose an H∞ approach to a remote control problem where the communication is constrained due to the use of a shared channel. The controller employs a periodic time sequencing scheme for message transmissions from multiple sensors and to multiple actuators of the system. It further takes into account the information on the random message losses that occur in the channel. An exact characterization for controller synthesis is obtained and is stated in terms of linear matrix inequalities. Furthermore, an analysis on the loss probabilities of the messages to accomplish stabilization is carried out. The results are illustrated through a numerical example. 相似文献