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131.
We describe how Intuitionistic Linear Logic can be used to provide a unified logical account for agents to find and execute
plans. This account supports the modelling of agent interaction, including dialogue; allows agents to be robust to unexpected
events and failures; and supports significant reuse of agent specifications. The framework has been implemented and several
case studies have been considered. Further applications include human–computer interfaces as well as agent interaction in
the semantic web. 相似文献
132.
Alan Mehlenbacher 《Computational Economics》2009,34(2):119-143
Computational experiments with a multiagent system show that bidders use signal averaging to avoid the winner’s curse in English
auctions. The results vary with the percent of common value in a two-dimensional value signal, information levels, uncertainty,
and the number of bidders. The complexity introduced by the combinations of these factors affects the bidding strategies and
auction outcomes in interesting ways—usually nonlinearly and sometimes non-monotonically. Of main concern to a seller is the
effect of these factors on revenue. I find that revenue increases with the percent of common value in the two-dimensional
value signal, decreases with uncertainty, and increases with the number of bidders. There is very little impact of information
level on revenue when values are pure private and pure common. However, for the intermediate cases of two-dimensional value
signals, revenue decreases with increased information.
相似文献
133.
In this work, we describe an autonomous mobile robotic system for finding, investigating, and modeling ambient noise sources
in the environment. The system has been fully implemented in two different environments, using two different robotic platforms
and a variety of sound source types. Making use of a two-step approach to autonomous exploration of the auditory scene, the
robot first quickly moves through the environment to find and roughly localize unknown sound sources using the auditory evidence
grid algorithm. Then, using the knowledge gained from the initial exploration, the robot investigates each source in more
depth, improving upon the initial localization accuracy, identifying volume and directivity, and, finally, building a classification
vector useful for detecting the sound source in the future. 相似文献
134.
Diego Dermeval Jéssyka Vilela Ig Ibert Bittencourt Jaelson Castro Seiji Isotani Patrick Brito Alan Silva 《Requirements Engineering》2016,21(4):405-437
There is an increase use of ontology-driven approaches to support requirements engineering (RE) activities, such as elicitation, analysis, specification, validation and management of requirements. However, the RE community still lacks a comprehensive understanding of how ontologies are used in RE process. Thus, the main objective of this work is to investigate and better understand how ontologies support RE as well as identify to what extent they have been applied to this field. In order to meet our goal, we conducted a systematic literature review (SLR) to identify the primary studies on the use of ontologies in RE, following a predefined review protocol. We then identified the main RE phases addressed, the requirements modelling styles that have been used in conjunction with ontologies, the types of requirements that have been supported by the use of ontologies and the ontology languages that have been adopted. We also examined the types of contributions reported and looked for evidences of the benefits of ontology-driven RE. In summary, the main findings of this work are: (1) there are empirical evidences of the benefits of using ontologies in RE activities both in industry and academy, specially for reducing ambiguity, inconsistency and incompleteness of requirements; (2) the majority of studies only partially address the RE process; (3) there is a great diversity of RE modelling styles supported by ontologies; (4) most studies addressed only functional requirements; (5) several studies describe the use/development of tools to support different types of ontology-driven RE approaches; (6) about half of the studies followed W3C recommendations on ontology-related languages; and (7) a great variety of RE ontologies were identified; nevertheless, none of them has been broadly adopted by the community. Finally, we conclude this work by showing several promising research opportunities that are quite important and interesting but underexplored in current research and practice. 相似文献
135.
136.
Wenguo LiuAuthor Vitae Alan F.T. Winfield Author Vitae 《Microprocessors and Microsystems》2011,35(1):60-67
In this paper we describe the implementation of a Linux extension board for the e-puck educational mobile robot, designed to enhance the computation, memory and networking performance of the robot at very low cost. The extension board is based on a 32-bit ARM9 microprocessor and provides wireless network support. The ARM9 extension board runs in parallel with the dsPIC microprocessor on the e-puck motherboard with communication between the two via an SPI bus. The extension board is designed to handle computationally intensive image processing, wireless communication and high-level intelligent robot control algorithms, while the dsPIC handles low-level sensor interfacing, data processing and motor control. The extension board runs an embedded Linux operating system, along with a Debian-based port of the root file system stored in a Micro SD card. The extended e-puck robot platform requires minimal effort to integrate the well-known open-source robot control framework Player and, when placed within a TCP/IP networked infrastructure, provides a powerful and flexible platform for experimental swarm robotics research. 相似文献
137.
The Kruskal-Wallis (KW) nonparametric analysis of variance is often used instead of a standard one-way ANOVA when data are from a suspected non-normal population. The KW omnibus procedure tests for some differences between groups, but provides no specific post hoc pair wise comparisons. This paper provides a SAS® macro implementation of a multiple comparison test based on significant Kruskal-Wallis results from the SAS NPAR1WAY procedure. The implementation is designed for up to 20 groups at a user-specified alpha significance level. A Monte-Carlo simulation compared this nonparametric procedure to commonly used parametric multiple comparison tests. 相似文献
138.
Adaptive Sampling for Network Management 总被引:3,自引:0,他引:3
Edwin A. Hernandez Matthew C. Chidester Alan D. George 《Journal of Network and Systems Management》2001,9(4):409-434
High-performance networks require sophisticated management systems to identify sources of bottlenecks and detect faults. At the same time, the impact of network queries on the latency and bandwidth available to the applications must be minimized. Adaptive techniques can be used to control and reduce the rate of sampling of network information, reducing the amount of processed data and lessening the overhead on the network. Two adaptive sampling methods are proposed in this paper based on linear prediction and fuzzy logic. The performance of these techniques is compared with conventional sampling methods by conducting simulative experiments using Internet and videoconference traffic patterns. The adaptive techniques are significantly more flexible in their ability to dynamically adjust with fluctuations in network behavior, and in some cases they are able to reduce the sample count by as much as a factor of two while maintaining the same accuracy as the best conventional sampling interval. The results illustrate that adaptive sampling provides the potential for better monitoring, control, and management of high-performance networks with higher accuracy, lower overhead, or both. 相似文献
139.
Alan Davis Sean Graves Terry Murray 《Journal of The Association for Laboratory Automation》2001,6(6):28-31
The genomics, proteomics, clinical, and drug discovery laboratories have a growing need to maintain valuable samples at ultra-low (−80°C) temperatures in a validated, secure environment. Automated sample processing systems have until now required manual (off-line) storage of samples at −80°C, reducing system reliability and speed. Both of these important needs are addressed by the Sample Process Management System being introduced by BIOPHILE Inc. Conventional sample management processes, such as storage, retrieval, and cataloging, are increasingly strained by the growing sample populations. There are variable sample types, access requirements and storage requirements. Security and inventory procedures are implemented manually. The evolving technologies present in the laboratory cannot interface with conventional manual storage techniques. Addressing these limitations, the primary benefits of BIOPHILE's solutions are:
- • Fully validated sample management process that coordinates the life-cycles of samples and their related data.
- • Robotic technology to securely store and retrieve samples, improving their accessibility and stability. Thermal shock is reduced, improving sample longevity and quality. The robotic technology allows integration with larger automation systems.
- • A process program to develop a Sample Management Strategy. This strategy is developed by analyzing long-term research goals, current baseline processes, and identification of current sample life cycles. A full validation documentation package can be generated, providing a high level of quality assurance.
- • Improved sample visibility and quality assurance - automated sample population cataloging; controlled sample management access and security.
140.