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21.
Indicating that CBMC does not satisfy the monotonic property in terms of the number of interactions, Xu and Zhou proposed an augmented definition of CBMC by adopting cut set instead of glue methods. The augmented CBMC clearly satisfies the monotonic property. However, CBMC is designed to overcome the problem with respect to the number of interactions and, therefore, focuses on the interaction pattern, especially, member connectivity. Consequently, it does not make sense to mention the monotonic property of CBMC with respect to interaction number. Moreover, the notion of glue methods allows several interpretations on the design quality of a class. However, that meaningful interpretation is not possible for the augmented definition due to the removal of the notion of glue methods. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
22.
Homogeneous and nano-sized BPNT [(Ba1-xPbx)Nd2Ti5O14] powders were prepared under various hydrothermal conditions. Crystallinity and homogeneity of the synthetic powders were
investigated. The microwave dielectric properties of the filters prepared with hydrothermal powders were compared with those
of the filters prepared with conventional powders. The microwave dielectric properties of the filter prepared with the hydrothermal
powders were also better than those of the filter manufactured with the conventional powders. The dielectric constant, quality
constant and temperature coefficient of resonance frequency of hydrothermally prepared filter under optimum condition and
measured at 3.5 GHz around were about 93, 6067 and 0 ppm/°C, respectively. 相似文献
23.
Failure to establish agreed-upon criteria by which to measure and identify online video game addiction has resulted in a lack of reliable evidence of the actual percentage of individuals who are pathologically dependent. Building upon prior research, the present study sought to better determine the magnitude of pathological online video game play using a distinction between core and peripheral criteria for behavioral addiction. Preferences and perceptions towards online video games and addiction were also examined to better understand players’ habits. A questionnaire was administered to 1332 South Korean students across 11 high schools and 1 middle school in an area surrounding the capital of Seoul. Using a monothetic and a polythetic classification system, findings showed rates ranging between 1.7% and 25.5%, with a 2.7% addiction rate when distinguishing core from peripheral criteria. These results may suggest that online video game addiction rates in intense gaming cultures such as South Korea are not as high as otherwise believed. The findings will be of assistance to educators, policymakers, clinicians, and researchers in understanding the challenges in deriving meaningful video game addiction prevalence rates, and thus being able to better separate reality from conjecture with regard to the notion of pathological game play. 相似文献
24.
Currently, embedded systems have been widely used for ubiquitous computing environments including digital setup boxes, mobile
phones, and USN (Ubiquitous Sensor Networks). The significance of security has been growing as it must be necessarily embedded
in all these systems. Up until now, many researchers have made efforts to verify the integrity of applied binaries downloaded
in embedded systems. The research of problem solving is organized into hardware methods and software-like methods. In this
research, the basic approach to solving problems from the software perspective was employed. From the software perspective,
unlike in the existing papers (Seshadri et al., Proc. the IEEE symposium on security and privacy, 2004; Seshadri et al., Proc. the symposium on operating systems principals, 2005) based on the standardized model (TTAS.KO-11.0054.
2006) publicized in Korea, there is no extra verifier and conduct for the verification function in the target system. Contrary
to the previous schemes (Jung et al. , 2008; Lee et al., LNCS, vol. 4808, pp. 346–355, 2007), verification results are stored in 1 validation check bit, instead of storing signature value for application binary files
in the i-node structure for the purpose of reducing run-time execution overhead. Consequently, the proposed scheme is more
efficient because it dramatically reduces overhead in storage space, and when it comes to computing, it performs one hash
algorithm for initial execution and thereafter compares 1 validation check bit only, instead of signature and hash algorithms
for every application binary. Furthermore, in cases where there are frequent changes in the i-node structure or file data
depending on the scheme application, the scheme can provide far more effective verification performance compared to the previous
schemes. 相似文献
25.
A method for evaluating fault coverage using simulated fault injection for digitalized systems in nuclear power plants 总被引:1,自引:0,他引:1
Suk Joon Kim Poong Hyun Seong Jun Seok Lee Man Cheol Kim Hyun Gook Kang Seung Cheol Jang 《Reliability Engineering & System Safety》2006,91(5):614-623
The fault coverage for digital system in nuclear power plants is evaluated using a simulated fault injection method. Digital systems have numerous advantages, such as hardware elements share and hardware replication of the needed number of independent channels. However, the application of digital systems to safety-critical systems in nuclear power plants has been limited due to reliability concerns. In the reliability issues, fault coverage is one of the most important factors. In this study, we propose an evaluation method of the fault coverage for safety-critical digital systems in nuclear power plants. The system under assessment is a local coincidence logic processor for a digital plant protection system at Ulchin nuclear power plant units 5 and 6. The assessed system is simplified and then a simulated fault injection method is applied to evaluate the fault coverage of two fault detection mechanisms. From the simulated fault injection experiment, the fault detection coverage of the watchdog timer is 44.2% and that of the read only memory (ROM) checksum is 50.5%. Our experiments show that the fault coverage of a safety-critical digital system is effectively quantified using the simulated fault injection method. 相似文献
26.
Seok Hwan Yoon 《Thin solid films》2006,515(4):1544-1547
Highly polycrystalline copper indium diselenide (CuInSe2) thin films on molybdenum substrate were successfully grown at 330 °C through two-stage metal organic chemical vapor deposition (MOCVD) method by using two precursors at relatively mild conditions. First, phase pure InSe thin film was prepared on molybdenum substrate by using a single-source precursor, di-μ-methylselenobis(dimethylindium). Second, on this InSe/Mo film, bis(ethylisobutyrylacetato) copper(II) designated as Cu(eiac)2 was treated by MOCVD to produce CuInSe2 films. The thickness and stoichiometry of the product films were found to be easily controlled in this method by adjusting the process conditions. Also, there were no appreciable amounts of carbon and oxygen impurities in the prepared copper indium diselenide films. 相似文献
27.
Hot band annealing is known to be a prerequisite for good magnetic properties irrespective of manufacturing methods in grain‐oriented Fe‐3 wt.% Si electrical steels. In this study, the effects of hot band annealing on magnetic properties were investigated in 3% grain‐oriented electrical steels of low soluble AI contents and one‐stage cold rolling. Microstructure and precipitate distribution were compared with hot band annealing conditions. Secondary recrystallization behaviour with hot band annealing condition was also discussed. 相似文献
28.
Hee Seok Song Jae Kyeong Kim Yeong Bin Cho Soung Hie Kim 《Artificial Intelligence Review》2004,21(2):161-184
Customer retention is an increasinglypressing issue in today's competitiveenvironment. This paper proposes a personalizeddefection detection and prevention procedurebased on the observation that potentialdefectors have a tendency to take a couple ofmonths or weeks to gradually change theirbehaviour (i.e., trim-out their usage volume)before their eventual withdrawal. For thispurpose, we suggest a SOM (Self-Organizing Map)based procedure to determine the possiblestates of customer behaviour from pastbehaviour data. Based on this staterepresentation, potential defectors aredetected by comparing their monitoredtrajectories of behaviour states with frequentand confident trajectories of past defectors.Also, the proposed procedure is extended toprevent the defection of potential defectors byrecommending the desirable behaviour state forthe next period so as to lower the likelihoodof defection. For the evaluation of theproposed procedure, a case study has beenconducted for a Korean online game site. Theresult demonstrates that the proposed procedureis effective for defection prevention andefficiently detects potential defectors withoutdeterioration of prediction accuracy whencompared to that of the MLP (Multi-LayerPerceptron) neural networks. 相似文献
29.
Seok Jin Lim Suk Jae Jeong Kyung Sup Kim Myon Woong Park 《The International Journal of Advanced Manufacturing Technology》2006,28(5-6):618-625
Today’s business environment is experiencing as a period of expansion and the globalization. Therefore, a distribution plan
with low cost and high customer satisfaction in supply chain management (SCM) has been widely investigated. The purpose of
this study is to establish optimal distribution planning in the supply chain. In this paper, a hybrid approach involving a
genetic algorithm (GA) and simulation is presented to solve this problem. The GA is employed in order to quickly generate
feasible distribution sequences. Considering uncertain factors such as queuing, breakdowns and repairing time in the supply
chain, the simulation is used to minimize completion time for the distribution plan. The computational results for an example
of a simple supply chain are given and discussed to validate the proposed approach. We obtained a more realistic distribution
plan with optimal completion time by performing the iterative hybrid GA simulation procedure which reflects the stochastic
nature of supply chains. 相似文献
30.
Hyung Seok Kim Chris Joslin Thomas Di Giacomo Stephane Garchery Nadia Magnenat-Thalmann 《The Visual computer》2006,22(5):332-345
The goal of this research was the creation of an adaptation mechanism for the delivery of three-dimensional content. The adaptation of content, for various network and terminal capabilities – as well as for different user preferences, is a key feature that needs to be investigated. Current state-of-the art research of the adaptation shows promising results for specific tasks and limited types of content, but is still not well-suited for massive heterogeneous environments. In this research, we present a method for transmitting adapted three-dimensional content to multiple target devices. This paper presents some theoretical and practical methods for adapting three-dimensional content, which includes shapes and animation. We also discuss practical details of the integration of our methods into MPEG-21 and MPEG-4 architectures. 相似文献