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291.
Wei-Der Chang 《Digital Signal Processing》2009,19(4):693-699
This paper presents a novel secure communication system for digital signal transmissions. It contains four important parts: modulation, chaotic transmitter, chaotic receiver, and demodulation. The modulation mechanism is to modulate each of delivered bit information to be a carrier signal in the continuous form. Then this carrier signal is taken as a parameter of the chaotic system, called the unified chaotic system. Such a system possesses three different types of chaos characterizations depending on its system's parameter, and this guarantees the communication security more. In the public channel, only three chaotic state variables are delivered and this means that the important carrier information is efficiently screened. According to chaotic states received in the receiver terminal, the continuous carrier signal is decrypted using certain adaptation mechanisms. Finally, the proposed demodulation method can successfully recover the original bit information which is embedded in the communication systems. Some simulation results are provided to verify the efficiency of the proposed secure communication system. 相似文献
292.
Youn‐Gyoung Chang Seong‐Hee Nam Nam‐Kook Kim Yun‐Ho Kook Jinook Kim Soon‐Sung Yoo Chang‐Dong Kim In‐Byeong Kang In‐Jae Chung 《Journal of the Society for Information Display》2009,17(4):301-307
Abstract— Recently, potential breakthrough technologies for low‐cost processing of TFT‐LCDs and new process developments for flexible‐display fabrication have been widely studied. A roll‐printing process using etch‐resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliché plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin‐film‐transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15‐in.‐XGA TFT‐LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used. 相似文献
293.
In a highly competitive market, customers' product affection is a critical factor to product success. However, understanding customers' affective needs is difficult to grasp; product design practitioners often misunderstand what customers really want. In this study we report our experience in developing and using an affective design framework that identified critical affective features customers have on products and are systematically incorporated into product design attributes. To identify key affective features such as luxuriousness, we utilized the Kansei engineering methodology. This approach consists of three steps: (1) selecting related affective features and product design attributes through a comprehensive literature survey, expert panel opinion, and focus group interviews; (2) conducting evaluation experiments; and (3) developing Kansei models using multivariate statistical analysis and analyzing critical product design attributes. To demonstrate applicability of the proposed affective design framework, 30 customers and 30 product design practitioners participated in an evaluation experiment for car crash pads, and 44 customers and 20 designers participated in an evaluation experiment for two interior room products (wallpapers and flooring materials). The evaluation experiments were conducted via systematically developed questionnaires consisting of a 7‐point semantic differential scale and a 100‐point magnitude estimation scale. The results of the experiments were analyzed using principal component regression and quantification theory type I method. Using the analyzed survey data, the relationship between luxuriousness and related affective features and product design attributes were identified. This relationship indicated that there was a significant difference in the perception of luxuriousness between customers and designers. Consequently, it is expected that the results of this study could provide a foundation for developing affective products. © 2009 Wiley Periodicals, Inc. 相似文献
294.
Yau-Zen Chang Jung-Fu Hou Yung-Pyng Chang Shih-Tseng Lee 《Artificial Life and Robotics》2009,14(2):228-232
In this article, we investigate the problem of integrating a binocular stereo vision system and a laser range finder to construct
a 3-D map of the environment. The proposed scheme is realized by using the alignment parameters obtained in the 2-D map construction
of the laser range finder for the 3-D data generated by the stereo vision system. The 2-D map alignment task is formulated
as an optimization problem of minimizing the alignment errors between local maps and selected parts of the developing global
map. The problem is then solved using the Simplex method. To increase the robustness of the searching process, multiple initial
guesses are provided in the Simplex method. The performance of the proposed architecture is verified by experimental results
from a mobile vehicle for obstacle avoidance. 相似文献
295.
Knowledge, experiences and skills of corporate members promote new ideas into products, in the context of innovative design. This dynamism is especially important in the critical product conceptualization stage. In customer-oriented design paradigm, most methodologies focus on exploiting end-user requirements, instead of considering project stakeholder requirements in a holistic manner. Previous research in the area of innovative product conceptualization focused on such aspects as functional, cognitive, marketing and commercial perspectives. It involves the participations of customers, designers, engineers, marketers and business managers. Accordingly, a stakeholder-oriented innovative product concept development system (IPCDS) is established to integrate the bespoke four perspectives so as to evaluate product concept innovation comprehensively. To resolve the incomplete, ambiguous, uncertain and subjective nature of innovative design knowledge, the product platform represented in a design knowledge hierarchy (DKH) is generated using general sorting. Subsequently, an innovative design criteria matrix (DCM) constructed using repertory grids technique is rated with regard to specific design option. The ratings are then used as input features to the fuzzy integrals technique, for the purpose of innovative design. A case study on cellular phone design is used for system illustration and the results are discussed on the basis of product concept innovation. 相似文献
296.
Previous research has shown that sub-population genetic algorithm is effective in solving the multi-objective combinatorial problems. Based on these pioneering efforts, this paper extends the SPGA algorithm with a global Pareto archive technique and a two-stage approach to solve the multi-objective problems. In the first stage, the areas next to the two single objectives are searched and solutions explored around these two extreme areas are reserved in the global archive for later evolutions. Then, in the second stage, larger searching areas except the middle area are further extended to explore the solution space in finding the near-optimal frontiers. Through extensive experimental results, SPGA II does outperform SPGA, NSGA II, and SPEA 2 in the parallel scheduling problems and knapsack problems; it shows that the approach improves the sub-population genetic algorithm significantly. It may be of interests for researchers in solving multi-objective combinatorial problems. 相似文献
297.
Devinder Thapa Chang Mok Park Sang C. Park Gi-Nam Wang 《International Journal of Control, Automation and Systems》2009,7(2):165-174
The objective of this paper is to reduce the development time of a PLC (Programmable Logic Controller) by automating the task
of code generation. For this purpose, we applied t-MPSG (Timed-Message Based Part State Graph). The t-MPSG is an extended finite state automata used to model and generate an execution module for a real-time shop floor controller
system. In our proposed method, t-MPSG is used to model the formal specification of the controller system that can be translated into textual structure. After
the verification of the t-MPSG model, it can be used as an input to the plc-builder tool. The plc-builder tool is an extended version of a conventional MPSG simulator. It can be used to translate the textual structure of
the t-MPSG into an IEC standard PLC code. Finally, the generated code can be downloaded to a PLC emulator or a PLC device for the
purpose of simulation and execution. The similarity in the hierarchical structure of the t-MPSG and the IEC standard PLC program has made it convenient to transform from one form to another. Furthermore, an illustration
of the methodology to auto-generate IEC standard PLC code using t-MPSG is explained with a suitable example.
Recommended by Editorial Board member Young Soo Suh under the direction of Editor Jae Weon Choi. This work was partially supported
by Defense Acquisition Program Administration and Agency for Defense Development under the contract (UD080042AD).
Devinder Thapa is a Postdoc Research Fellow in the Department of Industrial & information systems at Ajou University, Korea. He completed
his Ph.D. from Ajou University in Industrial and Information Systems Engineering. His area of research is related to manufacturing
automation and intelligent decision support systems.
Chang Mok Park is a Professor in the Department of Technology & Systems Management at Induk Institute of Technology. He completed his Ph.D.
in 2002 from Ajou University in Industrial Engineering. His research interest is related to manufacturing optimization, discrete
event system simulation and signal analysis.
Sang C. Park is an Associate Professor in the Department of Industrial & Information Systems Engineering at Ajou University. He received
his B.S., M.S., and Ph.D. degrees from KAIST in 1994, 1996, and 2000, respectively, all in Industrial Engineering. His research
interests include geometric algorithms in CAD/CAM, process planning, engineering knowledge management, and discrete event
system simulation.
Gi-Nam Wang is the Head and a Professor in the Department of Industrial & Information Systems Engineering at Ajou University, Korea.
He completed his Ph.D. in 1992 from Texas A&M University, in Industrial Engineering. He has worked as Visiting Professor at
University of Texas at Austin during 2000–2001. His area of research is related to Intelligent Information & manufacturing
systems, system integration & automation, e-Business solutions and image processing. 相似文献
298.
299.
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
300.
J2ME和J2EE技术是目前Java两大主要技术,并在应用中取得了成功。本文基于J2ME和J2EE技术实现了一个移动手机版的城市公交查询系统。其中,J2ME技术拥有移动手机客户端的开发,而J2EE技术则用于后台服务器和手机客户端的交互,以及后台服务器信息的发布。本系统实现了三种查询功能:路线查询、站点查询和站站查询。通过本系统将极大地方便手机用户对公交信息的查询。 相似文献