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971.
Estimating the cycle time of a job in a wafer fabrication plant (wafer fab) is a critical task to the wafer fab. Many recent studies have shown that pre-classifying a job before estimating the cycle time was beneficial to the forecasting accuracy. However, most pre-classification approaches applied in this field could not absolutely classify jobs. Besides, whether the pre-classification approach combined with the subsequent forecasting approach was suitable for the data was questionable. For tackling these problems, two hybrid approaches with example post-classification, the equally-divided method and the proportional-to-error method, are proposed in this study in which a job is post-classified by a back propagation network (BPN) instead after the forecasting error is generated. In this novel way, only jobs whose cycle time forecasts are the same accurate will be clustered into the same category, and the classification algorithm becomes tailored to the forecasting approach. For evaluating the effectiveness of the proposed methodology and to make comparison with some existing approaches, production simulation (PS) is applied in this study to generate test data. According to experimental results, the forecasting accuracy (measured with root mean squared error, RMSE) of the proportional-to-error method was significantly better than those of the other approaches in most cases by achieving a 26–56% (and an average of 41%) reduction in RMSE over the comparison basis – multiple-factor linear combination (MFLC). The effect of post-classification was also statistically significant. 相似文献
972.
973.
In order to effectively pump liquid in a fluidic chip, the PDMS or SU8 channels were frequently modified by surface treatments
to obtain the hydrophilic surface but encountered the problem of the hydrophobic recovery. In this article, long-term highly
hydrophilic fluidic chips were demonstrated using rapid fabrication of low-power CO2 laser ablation and low-temperature glass bonding with an interlayer of liquid crystal polymer (LCP). The intrinsic hydrophilic
materials of glass and LCP were beneficial for self-driven flow in the long-term fluidic chip by surface-tension force with
no extra fluidic pumps. The higher viscosity fluid could increase the difficulty of self-driven capability. The stability
of contact angle and flow test of the chip after 2 months is similar to that at beginning. The high-viscosity human whole
blood was successfully driven at an average moving velocity of about 1.89 mm/s for the beginning and at 2.04 mm/s after 2 months.
Our fluidic chip simplifies the traditional complex fabrication procedure of glass chips and conquers the problem of traditional
hydrophobic recovery. 相似文献
974.
MEMS-based gas flow sensors 总被引:1,自引:0,他引:1
Yu-Hsiang Wang Chang-Pen Chen Chih-Ming Chang Chia-Pin Lin Che-Hsin Lin Lung-Ming Fu Chia-Yen Lee 《Microfluidics and nanofluidics》2009,6(3):333-346
Micro-electro-mechanical system (MEMS) devices integrate various mechanical elements, sensors, actuators, and electronics
on a single silicon substrate in order to accomplish a multitude of different tasks in a diverse range of fields. The potential
for device miniaturization made possible by MEMS micro-fabrication techniques has facilitated the development of many new
applications, such as highly compact, non-invasive pressure sensors, accelerometers, gas sensors, etc. Besides their small
physical footprint, such devices possess many other advantages compared to their macro-scale counterparts, including greater
precision, lower power consumption, more rapid response, and the potential for low-cost batch production. One area in which
MEMS technology has attracted particular attention is that of flow measurement. Broadly speaking, existing micro-flow sensors
can be categorized as either thermal or non-thermal, depending upon their mode of operation. This paper commences by providing
a high level overview of the MEMS field and then describes some of the fundamental thermal and non-thermal micro-flow sensors
presented in the literature over the past 30 years or so. 相似文献
975.
Customized trapping of magnetic particles 总被引:1,自引:1,他引:0
This paper presents an efficient technique for trapping of magnetic particles in confined spatial locations using customized
designs of micro-coils (MCs). Large magnetic field gradients of up to 20 T/mm and large magnetic forces in the range of 10−8 Newton on magnetic particles with diameter of 1 μm have been achieved using MCs with several planar geometrical configurations.
A large magnetic field gradient is generated and enhanced by two structural parameters: the small width and high aspect ratio
of each single conductor and the ferromagnetic pillars positioned at high-flux density locations. This arrangement creates
very steep magnetic potential wells, in particular at the vicinity of the pillars. The system allowed capturing of suspended
magnetic particles as far as 1,000 μm from the center of the device. Magnetic particles/cells have been trapped and confined
in single and in arrays of deep magnetic potential wells corresponding to the MCs configuration. 相似文献
976.
The information resources on the Web are diversified, the amount of which is increasing rapidly. Demands for selecting useful
information from the Internet, managing personal contents, and sharing contents under control have risen. In this study, we
propose the Ubiquitous Personal Study, a framework of personalized virtual study to support accessing, managing, organizing,
sharing and recommending information. In this paper, we focus on discussing the framework, and design and implementation issues
on how to implement it with Web 2.0 mash-up technology and Open Source Software. 相似文献
977.
陈梦涵 《数码设计:surface》2009,(1):160-165
吃中餐如果在上海,总得去趟吴江路上的小杨生煎。朴素的店内片热火朝天的繁忙景象擀面的擀面,包馅的包馅,煎包子的煎包子,排队的排队,收钱的收钱。地道的上海大众小吃,只是你得眼尖手快,不然包子进嘴的时间要比会抢座位、会排队的那些食客长很多。 相似文献
978.
数码相机定位是计算机图形学中的一个重要课题,在图像处理等方面有着广泛的应用,对数码相机进行合理建模分析,并利用双目视觉原理对图像进行标定,最后例证了此方法的有效性和精确性。 相似文献
979.
介绍了一种可应用于被动声纳的时频域联合捕捉主动声纳信号的方法及其工作流程。仿真相同噪声环境下使用该方法的发现距离与主动声纳探测距离,仿真结果表明使用该方法的发现距离远超过主动声纳探测距离,使用该方法可实现对目标的远程发现。 相似文献
980.
依据不同频率子带特征反应语音的不同细节的特征,将语音信号子带分别分成4子带层,2子带层,1子带层共三层子带,分别提取其MFCC特征参数,并采用容易实现的矢量量化(VQ)识别算法加以识别,最后将三层子带识别率融合的方式,实现基于ARM9的说话人识别控制器。 相似文献