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991.
BACKGROUND/AIMS: To evaluate the technical feasibility and sensitivity of percutaneous transluminal forceps biopsy of bile duct diseases. MATERIAL AND METHODS: Seventeen fluoroscopic-guided transluminal forceps biopsies were performed in 16 patients with obstructive jaundice. The technique was performed through an existing percutaneous transhepatic tract. Multiple specimens were obtained after passing the forceps biopsy into a long 9-French sheath and the specimens were fixed with formalin for histopathologic diagnosis. RESULTS: Adequate samples for histological diagnosis was obtained in 12 of 17 procedures (sensitivity, 71%). Pathologic reports included pancreatic head carcinoma n = 2, cholangiocarcinoma n = 3, hepatoma with intrahepatic-bile duct invasion n = 3, common bile duct tumors n = 3 and chronic inflammation n = 1. Minor complications such as pain was noted in three patients while transient hemobilia was seen in two patients. CONCLUSIONS: Percutaneous transhepatic transluminal forceps biopsy is a safe technique which is easy to perform. This can be done through an existing transhepatic biliary tract with a sensitivity rate of 71%.  相似文献   
992.
基于S3C6410的田间视频监控系统的实现   总被引:2,自引:0,他引:2  
为实现农田实时监测,设计一种基于ARM11处理器的网络视频监控系统.系统以S3C6410作为网络监控系统的处理芯片,以USB摄像头为视频采集设备,通过有线方式接入互联网.详细阐述了嵌入式操作系统的移植与烧写,内核的剪裁与编译,以及Mjpg-streamer视频服务器软件的编译和移植.测试结果表明,系统在640×480分辨率下可以达到25fps的效果,传输视频稳定、清晰.  相似文献   
993.
This study uses the Received Signal Strength Indication (RSSI) values of RFID to predict the position of picking staff for warehouse management. A proposed feature selection-based back-propagation (BP) neural network that uses an artificial immune system (AIS) (FSBP-AIS) to determine the connecting weights of a neural network learns the relationship between the RSSI values and the position of the picking staff. In addition, the proposed FSBP-AIS is able to determine the representative features, or inputs, during training. Once a picking staff's position is known, this information is used to plan the picking route for picking staff if a new order arrives. The computational results indicate that the proposed FSBP-AIS can provide better predictions than a traditional BP neural network, BP neural network with stepwise regression to determine the important inputs, and regression method.  相似文献   
994.
This article introduces a novel hybrid evolutionary algorithm for recurrent fuzzy neural systems design in applications of nonlinear systems. The hybrid learning algorithm, IEMBP-improved electromagnetism-like (EM) with back-propagation (BP) technique, combines the advantages of EM and BP algorithms which provides high-speed convergence, higher accuracy and less computational complexity (computation time in seconds). In addition, the IEMBP needs only a small population to outperform the standard EM that uses a larger population. For a recurrent neural fuzzy system, IEMBP simulates the ‘attraction’ and ‘repulsion’ of charged particles by considering each neural system parameters as a charged particle. The EM algorithm is modified in such a way that the competition selection is adopted and the random neighbourhood local search is replaced by BP without evaluations. Thus, the IEMBP algorithm combines the advantages of multi-point search, global optimisation and faster convergence. Finally, several illustration examples for nonlinear systems are shown to demonstrate the performance and effectiveness of IEMBP.  相似文献   
995.
Yu-Chen Kuo 《Computer Networks》2010,54(11):1911-1922
The asynchronous PS (Power-Saving) unicast protocol was designed for two PS wireless hosts to transmit the unicast message in the ad hoc network even their clocks are asynchronous. However, as regard to transmit a multicast message among more than two PS hosts, the protocol could not guarantee that all PS hosts can wake up at the same time. Some PS hosts may be in the PS mode when the multicast message is transmitted. Thus, the multicast message should be retransmitted again and again until all PS hosts receive the message. It will increase the energy consumption and the usage of the bandwidth. In this paper, we propose quorum-based PS multicast protocols for PS hosts to transmit multicast messages in the asynchronous ad hoc network. In those protocols, PS hosts use quorums to indicate their wakeup patterns. We introduce the rotation m-closure property to guarantee that m different quorums have the intersection even quorums are rotated due to asynchronous clocks. Thus, m PS hosts adopting m quorums satisfying the rotation m-closure property could wake up simultaneously and receive the multicast message even their clocks are asynchronous. We propose two quorum systems named the uniform k-arbiter and the CRT (Chinese Remainder Theorem) quorum system, which satisfy the rotation m-closure property. As shown in our analysis results, our quorum-based PS multicast protocols adopting those quorum systems can save more energy to transmit multicast messages.  相似文献   
996.
This article presents a model based approach to autonomous dexterous manipulation, developed as part of the DARPA Autonomous Robotic Manipulation Software (ARM-S) program. Performing human-level manipulation tasks is achieved through a novel combination of perception in uncertain environments, precise tool use, forceful dual-arm planning and control, persistent environmental tracking, and task level verification. Deliberate interaction with the environment is incorporated into planning and control strategies, which, when coupled with world estimation, allows for refinement of models and precise manipulation. The system takes advantage of sensory feedback immediately with little open-loop execution, attempting true autonomous reasoning and multi-step sequencing that adapts in the face of changing and uncertain environments. A tire change scenario utilizing human tools, discussed throughout the article, is used to described the system approach. A second scenario of cutting a wire is also presented, and is used to illustrate system component reuse and generality.  相似文献   
997.
Journal of Intelligent & Robotic Systems - This paper proposes a digital twin (DT) framework for point source applications in environmental sensing (ES). The DT concept has become quite popular...  相似文献   
998.
In recent years, many modern phased-array radars are built with commercial off-the-shelf components, and the functions of many hardware components are also reimplemented by software modules. In such systems, radar tasks could be modeled as distributed real-time tasks which require end-to-end deadline guarantees and have precedence constraints. Different from most previous work on either algorithms with restrictions in resource utilization or heuristics without analytical ways for schedulability guarantees, the objective of this paper is to propose a joint real-time scheduling algorithm for both transmitter/receiver and signal processor workloads with an analytical framework for offline probabilistic analysis and online admission control. The strength of our approach is verified by analysis results and a series of experiments based on a real phased-array radar for air defense frigates.  相似文献   
999.
In a 300 mm integrated circuit (IC) foundry fab, the intrabay automation is more important than a 200 mm one. In general, the intrabay automation systems include the automated controls of the process tools, overhead hoist transports (OHTs), stockers, and rail shortcuts. These control systems are operated concurrently. They must cooperate seamlessly to increase the system performance and to avoid deadlocks. In the paper, the behaviors of the intrabay automation systems are modeled using the distributed agent oriented Petri net (DAOPN). The fab intrabay DAOPN models are categorized into the new-order generation, OHT vehicle dispatching, zone control, path decision, and tool processing agent models. Finally, the DAOPN is defined, and the modeling procedures of the intrabay behaviors are all illustrated. Consequently, an experimental intrabay OHT loop is discussed and evaluated using the proposed DAOPN models and the DAOPN simulator.  相似文献   
1000.
HAGI is an object-oriented graphics system developed on top of the X window system. In addition to providing facilities that structured graphics systems such as GKS usually have, HAGI supports a high- level graphics paradigm with the following features:
  • + In addition to graphical objects, the system provides a class of application objects with a higher level of abstraction than graphical objects.
  • + Graphics manipulation operations can be issued simplyfrom application objects without explicitly referring to specific graphical objects. Thus graphics manipulation appears to be transparent to application programmers.
  • + Graphical objects are designed to encompass more semantics, thus are at a level close to the application. For example, they useflexible visual objects to determine their visual appearance.
HAGI provides such a high-level application/graphics interface by maintaining a dependency relationship between graphical objects and application objects.  相似文献   
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