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81.
Recent advances in multimedia technologies have made imaging devices and image editing tools ubiquitous and affordable. Image editing done with malicious intent is called as image tampering or forgery. The most common forgery is the copy-move forgery which involves copying a part of an image and pasting it on some other part of the same image. There are many existing methods for such forgery detection, but most of them are sensitive to post-processing and do not detect multiple instances of forgeries in an image. In the proposed approach, affine transformation property preservation of clustered keypoints in the image is used, which includes the tests for collinearity and distance ratio preservation. Our method is also able to detect multiple copy-move forgeries within an image. The proposed method is tested against four image tampering detection datasets, and the results of our method are the best compared to the existing eight state-of-the-art methods in terms of accuracy.  相似文献   
82.
Journal of Materials Science: Materials in Electronics - Real-time interpretation and modification of information can impart revolutionary advancements in the evolution of the internet of things....  相似文献   
83.
This paper presents an approach which enables surface modelling, mesh generation and the Finite Element (FE) analysis to be integrated together to simulate superplastic forming process for complex shaped components. Techniques have been developed to generate an FE mesh over non-four-sided surface areas, the boundaries of which are Bezier curves of arbitrary degree, using a consistent expression. Theoretical evidence is given to determine the number of Bezier triangular patches required for accurately re-constructing die surfaces within a commercial FE solver. The developed techniques have been successfully used in determining the process parameters for forming a 3D rectangular box.  相似文献   
84.
This paper argues for a need to develop methods for examining temporal patterns in computer-supported collaborative learning (CSCL) groups. It advances one such quantitative method—Lag-sequential Analysis (LsA)—and instantiates it in a study of problem-solving interactions of collaborative groups in an online, synchronous environment. LsA revealed significant temporal patterns in CSCL group discussions that the commonly used “coding and counting” method could not reveal. More importantly, analysis demonstrated how variation in temporal patterns was significantly related to variation in group performance, thereby bolstering the case for developing and testing temporal methods and measures in CSCL research. Findings are discussed, including issues of reliability, validity, and limitations of the proposed method.  相似文献   
85.
Successful E-Business is based on seamless collaborative business processes. Each partner in the collaboration specifies its own rules and interaction preconditions. The verification of the compatibility of collaborative business processes, based on local and global views, is a complex task, which is critical for the success of the cooperation. The verification of process compatibility should be a key element in the design of new business alliances, which makes this verification essential in inter-organizational business process design. The advent of Web Services and Service Oriented Architectures stresses the need to solve complex business cooperations under the pressure of reduced costs and risks, combined with shorter time to market. At the same time, the message-based paradigm results in large and complex processes which makes the verification process quite hard.First the use of an atomic business activity based interaction paradigm is proposed to reduce the complexity of collaborative process models. Next, formal compatibility criteria for business processes are developed. The key construction is the notion of semantic compatibility, which can be used to assess the compatibility of the publicly exposed behavior (a.k.a. business interfaces) between business partners in joint business processes. The formal nature of this compatibility allows to give a precise indication of the degree of compatibility between cooperating business partners. It enables exhaustive lists of incompatible (i.e. unsupported scenarios) business cooperations, which is more comprehensive and complete than the typical compatible or incompatible answer to this question. Finally, complex multiple party interactions can be examined in terms of the safety of the interaction protocols.  相似文献   
86.
Enterprise architecture (EA) is a coherent whole of principles, methods, and models that are used in the design and realization of an enterprise’s organizational structure, business processes, information systems, and IT infrastructure. Recent research indicates the need for EA in small and medium-sized enterprises (SMEs), important drivers of the economy, as they struggle with problems related to a lack of structure and overview of their business. However, existing EA frameworks are perceived as too complex and, to date, none of the EA approaches are sufficiently adapted to the SME context. Therefore, this paper presents the CHOOSE metamodel for EA in SMEs that was developed and evaluated through action research in an SME and further refined and validated through case study research in five other SMEs. This metamodel is based on the essential dimensions of EA frameworks and is kept simple so that it may be applied in an SME context. The final CHOOSE metamodel includes only four essential concepts (i.e. goal, actor, operation, object), one for each most frequently used EA focus. As an example, an extract is included from the specific model that was created for the SME used in our action research. Finally, the CHOOSE metamodel is evaluated according to the dimensions essential in EA and the requirements for EA in an SME context.  相似文献   
87.
In this correspondence, we propose a wavelet-based hierarchical approach using mutual information (MI) to solve the correspondence problem in stereo vision. The correspondence problem involves identifying corresponding pixels between images of a given stereo pair. This results in a disparity map, which is required to extract depth information of the relevant scene. Until recently, mostly correlation-based methods have been used to solve the correspondence problem. However, the performance of correlation-based methods degrades significantly when there is a change in illumination between the two images of the stereo pair. Recent studies indicate MI to be a more robust stereo matching metric for images affected by such radiometric distortions. In this short correspondence paper, we compare the performances of MI and correlation-based metrics for different types of illumination changes between stereo images. MI, as a statistical metric, is computationally more expensive. We propose a wavelet-based hierarchical technique to counter the increase in computational cost and show its effectiveness in stereo matching.  相似文献   
88.
The paper presents theoretical support for and describes the use of a fuzzy paradigm in implementing a TTS system for the Romanian language, employing a rule-based formant synthesizer. In the framework of classic TTS systems, we propose a new approach in order to improve formant trace computation, aiming at increasing synthetic speech perceptual quality. A fuzzy system is proposed for solving the problem of the phonemes that are prone to multi-definitions in rule-based speech synthesis. In the introductory section, we briefly present the background of the problem and our previous results in speech synthesis. In the second section, we deal with the problem of the context-dependent phonemes at the letter-to-sound module level of our TTS system. Then, we discuss the case of the phoneme /l/ and the solution adopted to define it for different contexts. A fuzzy system is associated with each parameter (denoted F1 and F2) to implement the results of the complete analysis of the phoneme /l/ behavior. The knowledge used in implementing the fuzzy module is acquired by natural speech analysis. In the third section, we exemplify the computation of the synthesis parameters F1 and F2 of the phoneme /l/ in the context of the two syllable sequences. The parameter values are contrasted with those obtained from the spectrogram analysis of the natural speech sequences. The last section presents the main conclusions and further research objectives.  相似文献   
89.
Today many business enterprises employ capital assets in the form of electronic equipment, such as personal computers, workstations and peripherals, in large quantities. Due to rapid technological progress (leading to a short life cycle for these products), and hazardous material content in electronic products (which is an environmental problem and a disposal challenge), leasing or procurement contracts with take-back considerations can be attractive. For a large electronic equipment leasing company, optimal management of assets supported by good logistics and end-of-life processing decisions is crucial, and may provide a significant competitive advantage. There is currently no analytic approach for making these decisions in an integrated fashion.  相似文献   
90.
Many biological phenomena such as locomotion, circadian cycles and breathing are rhythmic in nature and can be modelled as rhythmic dynamical systems. Dynamical systems modelling often involves neglecting certain characteristics of a physical system as a modelling convenience. For example, human locomotion is frequently treated as symmetric about the sagittal plane. In this work, we test this assumption by examining human walking dynamics around the steady state (limit-cycle). Here, we adapt statistical cross-validation in order to examine whether there are statistically significant asymmetries and, even if so, test the consequences of assuming bilateral symmetry anyway. Indeed, we identify significant asymmetries in the dynamics of human walking, but nevertheless show that ignoring these asymmetries results in a more consistent and predictive model. In general, neglecting evident characteristics of a system can be more than a modelling convenience—it can produce a better model.  相似文献   
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