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111.
Pradipta K. Nayak Jongsu Jang Changhee Lee Yongtaek Hong 《Journal of the Society for Information Display》2010,18(8):552-557
Abstract— The effects of lithium (Li) doping concentration and gate dielectrics on the performance of solution‐processed zinc‐oxide (ZnO) thin‐film transistors (TFTs) has been investigated. ZnO films with strong c‐axis orientation and lower background conductivity was obtained with 15 at.% of Li. Different crystallization behavior of ZnO was observed in the case of various dielectric surfaces. The 15‐at.% Li‐doped ZnO films (thickness ~20 nm) prepared on SiO2 and SiNx were found to be present in crystalline form, whereas the film prepared on aluminum titanium oxide (ATO) was found to be amorphous. A field‐effect mobility of 1.81 cm2/V‐sec and an Ion/Ioff ratio of 2 × 106 were obtained for the 15‐at.% Li‐doped ZnO TFTs with a bilayer gate dielectric of SiO2 and SiNx. The comparison of dielectric studies showed that the performance of TFTs prepared on SiNx and ATO are higher than that of the TFTs prepared on SiO2. 相似文献
112.
The field of micro–electro–mechanical systems and microfabrication has produced micro-total-analysis systems, which are widely
used in medicine, diagnostics, and biological and chemical research. For the development of high precision drug delivery systems,
micropumps with a lead zirconate titanate (PZT) actuator, which has a fast response time and high resolution, are most likely
to be applied in implementations. To improve the performance of PZT micropumps utilized in the microfluidics field, suitable
models are required to enable the optimization of the PZT actuator driving circuits. This study proposes a modified Butterworth–Van
Dyke (BVD) model which consists of a BVD model in series with an electrical resistance that describes a PZT actuator driven
by a square pulse with a relatively high voltage and low frequency for micropump applications. Experiments were conducted
to assess parameters of the model at various voltages; they indicate that the electrical resistance is essential for modeling
the PZT actuator of the micropump. The electrical model was verified using a SPICE simulation, whose numerical results were
compared with the experimental data for the current response of the PZT actuator. The results show a close correlation between
the simulation of the electrical model and the measurements of the PZT actuator under real operating conditions. 相似文献
113.
With the increased incidence of depression-related disorders, many psychiatric websites have been developed to provide huge amounts of educational documents along with rich self-help information. Psychiatric document retrieval aims to assist individuals to locate documents relevant to their depressive problems efficiently and effectively. By referring to relevant documents, individuals can understand how to alleviate their depression-related symptoms according to recommendations from health professionals. This work proposes the use of high-level discourse information extracted from queries and documents to improve the precision of retrieval results. The discourse information adopted herein includes negative life events, depressive symptoms and semantic relations between symptoms, which are beneficial for better understanding of users' queries. Experimental results show that the discourse-aware retrieval model achieves higher precision than the word-based retrieval models, namely the vector space model (VSM) and Okapi model, adopting word-level information alone. 相似文献
114.
Sang-Hoon Kim Jang Hyun Kim Junho Yang Hyunseok Yang Joo-Youn Park Young-Pil Park 《Microsystem Technologies》2009,15(10-11):1695-1700
Recently photopolymer with disk type substrate is selected as a media of the holographic data storage system. Because shape of the media is a disk, a disk tilt must be occur when the media rotates. When disk tilt occurs the angle between the reference beam and the media is changed by the tilt, thus the data can not be recorded with a right angle or another data page is retrieved. The holographic data storage system is very weak to the tilt disturbance by the Bragg effect, therefore it is necessary to detect the disk tilt angle and compensate it. In this study, we measure the amount of the tilt error using external photo detector and compensate it by rotating the angle of galvano mirror with our own algorithm. 相似文献
115.
Ming-Da Ma Chun-Cheng Chang David Shan-Hill Wong Shi-Shang Jang 《Journal of Process Control》2009,19(4):591-603
In the semiconductor manufacturing industry, production resembles an automated assembly line in which many similar products with slightly different specifications are manufactured step-by-step, with each step being a complicated physiochemical batch process performed by a number of tools. This constitutes a high-mix production system for which effective run-to-run control (RtR) and fault detection control (FDC) can be carried out only if the states of different tools and different products can be estimated. However, since in each production run, a specific product is performed on a specific tool, absolute individual states of products and tools are not observable. In this work, a novel state estimation method based on analysis of variance (ANOVA) is developed to estimate the relative states of each product and tool to the grand average performance of this station in the fab. The method is formulated in the form of a recursive state estimation using the Kalman filter. The advantages of this method are demonstrated using simulations to show that the correct relative states can be estimated in production scenarios such as tool-shift, tool-drift, product ramp-up, tool/product-offline and preventive maintenance (PM). Furthermore, application of this state estimation method in RtR control scheme shows that substantial improvements in process capabilities can be gained, especially for products with small lot counts. The proposed algorithm is also evaluated by an industrial application. 相似文献
116.
在信息系统的应用中,为了保证信息的安全使用,为了打破各应用系统间的信息孤岛,降低维护管理成本,切实有效的保证用户身份信息的安全性、完整性、一致性和可用性,最好的方法就是建立一套用户信息管理使用体系,这套体系也就是用户信息资源在所有应用系统中的统一认证和统一授权管理支撑系统。为了解决多系统中存在的多重口令管理而提出的解决方案,它应有统一用户信息资源管理、统一用户身份认证和认证接口服务等三大主要部分组成。也就是要建立权威的、适合各应用系统使用的统一帐号数据库;利用这个统一帐号数据库,通过各应用系统的用户信息的接口,实现用户在各应用系统中的身分识别。统一用户身分识别或认证只是实现了用户统一管理的第一步,要实现用户统一授权,在用户统一认证的基础上完成用户角色管理,通过把用户加入到某一种角色来实现该用户的权限分配,管理员可以添加自定义的角色,从而实现灵活的系统配置;完成模块管理,为控制用户使用系统各功能模块的权限,把系统中所有的功能项添加到模块表中,添加到表中的模块以菜单的形式显示在系统中,增加新的功能模块时,添加模块表,把新增的模块纳入一致的权限管理范畴;完成模块授权配置,对系统各个模块进行定义,并设置对哪些角色、部... 相似文献
117.
Won Tae Lee Jae Wook Lee Hyeon Yong Jang Seoung Jae Im SeGi Yu Jong Min Kim 《Journal of the Society for Information Display》2001,9(1):35-40
A new protecting layer, a LaF3‐coated MgO layer, in color AC‐plasma‐display panels (PDPs) was studied in order to overcome the weakness of the conventional single MgO protecting layer. The material characteristics of the new layer were examined by using variations in the deposition process. The display characteristics were also examined by implementing their processes to actual PDPs. It was demonstrated that this method is effective in lowering the firing and sustaining voltages of PDPs and enhancing the brightness of the panel as well. 相似文献
118.
Se Hwan Kim Eung Bum Kim Jae Hwan Oh Ji Ho Hur Jin Jang 《Journal of the Society for Information Display》2008,16(3):415-419
Abstract— A 2.0‐in. a‐Si:H TFT‐LCD with embedded TFT sensors for the control of the backlight intensity according to the ambient light intensity has been developed. Two types of a‐Si:H TFT sensors with various channel widths were embedded into a TFT backplane with bottom‐ and top‐gate structures for measuring the ambient light and backlight illumination, respectively. The output signal, measured by a readout IC, increased with backlight intensity until 20,000 lux. 相似文献
119.
Jang R Karwowski W Quesada PM Rodrick D Sherehiy B Cronin SN Layer JK 《Ergonomics》2007,50(11):1835-1855
A field study was conducted to investigate spinal kinematics and loading in the nursing profession using objective and subjective measurements of selected nursing tasks observed in a hospital setting. Spinal loading was estimated using trunk motion dynamics measured by the lumbar motion monitor (LMM) and lower back compressive and shear forces were estimated using the three-dimensional (3D) Static Strength Prediction Program. Subjective measures included the rate of perceived physical effort and the perceived risk of low back pain. A multiple logistic regression model, reported in the literature for predicting low back injury based on defined risk groups, was tested. The study results concluded that the major risk factors for low back injury in nurses were the weight of patients handled, trunk moment, and trunk axial rotation. The activities that required long time exposure to awkward postures were perceived by nurses as a high physical effort. This study also concluded that self-reported perceived exertion could be used as a tool to identify nursing activities with a high risk of low-back injury. 相似文献
120.
A sparser but more efficient connection rule (called a bond-cutoff method) for a simplified alpha-carbon coarse-grained elastic network model is presented. One of conventional connection rules for elastic network models is the distance-cutoff method, where virtual springs connect an alpha-carbon with all neighbor alpha-carbons within predefined distance-cutoff value. However, though the maximum interaction distance between alpha-carbons is reported as 7 angstroms, this cutoff value can make the elastic network unstable in many cases of protein structures. Thus, a larger cutoff value (>11 angstroms) is often used to establish a stable elastic network model in previous researches. To overcome this problem, a connection rule for backbone model is proposed, which satisfies the minimum condition to stabilize an elastic network. Based on the backbone connections, each type of chemical interactions is considered and added to the elastic network model: disulfide bonds, hydrogen bonds, and salt-bridges. In addition, the van der Waals forces between alpha-carbons are modeled by using the distance-cutoff method. With the proposed connection rule, one can make an elastic network model with less than 7 angstroms distance cutoff, which can reveal protein flexibility more sharply. Moreover, the normal modes from the new elastic network model can reflect conformational changes of a given protein better than ones by the distance-cutoff method. This method can save the computational cost when calculating normal modes of a given protein structure, because it can reduce the total number of connections. As a validation, six example proteins are tested. Computational times and the overlap values between the conformational change and infinitesimal motion calculated by normal mode analysis are presented. Those animations are also available at UMass Morph Server (http://biomechanics.ecs.umass.edu/umms.html). 相似文献