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51.
52.
A relationship between the impact transition temperatureT i and the stress concentration factorK s is derived. The relationship involves the temperature shift factora T; in turn,a T depends on the free volume. In earlier work in this problem Zewi and Corneliussen [6] utilized the W-L-F equation. Here a more direct relationship betweena T and the free volume is applied. Satisfactory values ofK s corresponding to givenT i are obtained for a wide temperature range; the range also includes temperatures below the glass transition pointT g. The opinion that a free volume exists between 0 K andT g is upheld.  相似文献   
53.
In this study, we are concerned with system modeling which involves limited data and reconciles the developed model with some previously acquired domain knowledge being captured in the format of already constructed models. Each of these previously available models was formed on a basis of extensive data sets which are not available for the current identification pursuits. To emphasize the nature of modeling being guided by the reconciliation mechanisms, we refer to this mode of identification as experience-consistent modeling. The paper presents the conceptual and algorithmic framework by focusing on regression models. By forming a certain extended form of the performance index, it is shown that the domain knowledge captured by regression models can play a similar role as a regularization component used quite commonly in system identification. Experimental results involve both synthetic low-dimensional data and selected data coming from Machine Learning repository. The data used in the experiments tackle regression models as well as classification problems (two-class classifiers).  相似文献   
54.
In this paper, we propose and investigate a new category of neurofuzzy networks—fuzzy polynomial neural networks (FPNN) endowed with fuzzy set-based polynomial neurons (FSPNs) We develop a comprehensive design methodology involving mechanisms of genetic optimization, and genetic algorithms (GAs) in particular. The conventional FPNNs developed so far are based on the mechanisms of self-organization, fuzzy neurocomputing, and evolutionary optimization. The design of the network exploits the FSPNs as well as the extended group method of data handling (GMDH). Let us stress that in the previous development strategies some essential parameters of the networks (such as the number of input variables, the order of the polynomial, the number of membership functions, and a collection of the specific subset of input variables) being available within the network are provided by the designer in advance and kept fixed throughout the overall development process. This restriction may hamper a possibility of developing an optimal architecture of the model. The design proposed in this study addresses this issue. The augmented and genetically developed FPNN (gFPNN) results in a structurally optimized structure and comes with a higher level of flexibility in comparison to the one we encounter in the conventional FPNNs. The GA-based design procedure being applied at each layer of the FPNN leads to the selection of the most suitable nodes (or FSPNs) available within the FPNN. In the sequel, two general optimization mechanisms are explored. First, the structural optimization is realized via GAs whereas the ensuing detailed parametric optimization is carried out in the setting of a standard least square method-based learning. The performance of the gFPNN is quantified through experimentation in which we use a number of modeling benchmarks—synthetic and experimental data being commonly used in fuzzy or neurofuzzy modeling. The obtained results demonstrate the superiority of the proposed networks over the models existing in the references.  相似文献   
55.
As a useful information representation tool, hesitant fuzzy linguistic term set (HFLTS) allows decision makers (DMs) to express their cognitive preferences in terms of several ordered and continuous linguistic terms. Considering the fact that much valuable information related to the cognitive behavior of DMs is hidden in the original evaluation information, this paper studies how to comprehensively mine uncertain information from original hesitant fuzzy linguistic evaluation information given by DMs. To address this objective, we present a new representation tool, normal wiggly hesitant fuzzy linguistic term set (NWHFLTS), which not only retains the original evaluation information, but also delivers and quantifies potential uncertain information, and can also help DMs express their evaluation information in a more complete manner. First, we develop the basic operations, score function, and comparison rule of NWHFLTS based on linguistic scale functions (LSFs), and propose the projection measure, the normal projection measure, and the normalized projection-based distance measure to describe the degree of deviation between two NWHFLTSs. Furthermore, for the case when the attribute weight is completely unknown, we combine the multiattributive border approximation area comparison (MABAC) method and develop a new method called as normal wiggly hesitant fuzzy linguistic projection-based MABAC to solve the multiattribute decision-making problems where attribute values are expressed in the form of NWHFLTS. Finally, through a practical example of marine ecological security situation, the specific calculation steps of this method are exemplified, the feasibility and advancement of the proposed method are demonstrated via a comprehensive comparative study.  相似文献   
56.
Many small software organizations have recognized the need to improve their software product. Evaluating the software product alone seems insufficient since it is known that its quality is largely dependant on the process that is used to create it. Thus, small organizations are asking for evaluation of their software processes and products. The ISO/IEC 14598-5 standard is already used as a methodology basis for evaluating software products. This article explores how it can be combined with the CMMI to produce a methodology that can be tailored for process evaluation in order to improve their software processes. SM: CMMI is a service mark of Carnegie-Mellon University. Sylvie Trudel has over 20 years of experience in software. She worked for more than 10 years in development and implementation of management information systems and embedded real-time systems. Since 1996, she works as a process improvement specialist, implementing best practices into organizations processes from CMM and CMMI models. She performed several CMM and CMMI assessments and participated in many other CMM assessments such as CBA IPI, SCE, and other proprietary methods. She obtained a bachelors degree in computer science in 1986 from Laval University in Québec City and a Masters degree in Software Engineering at école de Technologie Supérieure (éTS) in Montréal. Sylvie is currently working as a software engineering advisor at the Centre de Recherche Informatique de Montréal (CRIM). Jean-Marc Lavoie has been working in software development for over 10 years. He performed and published a comparative study between the guide to the SWEBOK and the CMMI in 2003. Jean-Marc obtained a bachelor degree in Electrical Engineering. He is pursuing a Masters degree in Software Engineering at école de Technologie Supérieure (éTS) in Montréal while working as a software architect at Trisotech. Marie-Claude Pare has been working in software development for 7 years. Marie-Claude obtained a bachelor degree in Software Engineering from école Polytechnique in Montréal. She is pursuing a Masters degree in Software Engineering at école de Technologie Supérieure (éTS) in Montréal while working as a software engineer at Motorola GSG Canada. Dr Witold Suryn is a Professor at the école de technologie supérieure, Montreal, Canada (engineering school of the Université du Québec network of institutions) where he teaches graduate and undergraduate software engineering courses and conducts research in the domain of software quality engineering, software engineering body of knowledge and software engineering fundamental principles. Dr Suryn is also the principal researcher and the director of GELOG : IQUAL, the Software Quality Engineering Research Group at école de technologie supérieure. From October 2003 Dr. Suryn holds the position of the International Secretary of ISO/IEC SC7 – System and Software Engineering.  相似文献   
57.
We introduce a new architecture of feed-forward neural networks called hybrid fuzzy set-based polynomial neural networks (HFSPNNs) that are composed of heterogeneous feed-forward neural networks such as polynomial neural networks (PNNs) and fuzzy set-based polynomial neural networks (FSPNNs). We develop their comprehensive design methodology by embracing mechanisms of genetic optimization and information granulation. The construction of information granulation-driven HFSPNN exploits fundamental technologies of computational intelligence (CI), namely fuzzy sets, neural networks, and genetic algorithms (GAs). The architecture of the resulting information granulation-driven genetically optimized HFSPNN results from a synergistic usage of the hybrid system generated by combining original fuzzy set-based polynomial neurons (FSPNs)-based FSPNN with polynomial neurons (PNs)-based PNN. The design of the conventional genetically optimized HFPNN exploits the extended Group Method of Data Handling (GMDH) whose some essential parameters of the network being tuned with the use of genetic algorithms throughout the overall development process. Two general optimization mechanisms are explored. First, the structural optimization is realized via GAs while the ensuing detailed parametric optimization is carried out in the setting of a standard least square method-based learning. The performance of the gHFSPNN is quantified through extensive experimentation where we considered a number of modeling benchmarks (synthetic and experimental data already experimented with in fuzzy or neurofuzzy modeling).  相似文献   
58.
It has long been known that highly soluble salts or hydrate-forming salts can damage porous building material. There is a real challenge to provide salt assessment in compliance with good monuments diagnosis and restoration practices. The salts present in the masonry can be analysed qualitatively and quantitatively by means of several techniques. Nowadays, the standard analytical equipment as ion chromatography (IC) found in several laboratories is a reliable method for analysing a large variety of anions and cations in solutions (or building materials water extracts), in order to meet international standards and regulations. However, preliminary study and diagnosis of soluble salt present in monuments do not necessarily require such a precise (SD < 5%) and sensitive (ppm or ppb range) analyses. Some simple-to-use techniques, such as hygroscopic moisture content (HMC) and electrical conductivity (EC) of extracted salt solutions, are widely in use to provide indications on the presence of salts.This paper presents a comparison of salt assessment obtained by IC, HMC and EC methods, and provides the domain of their application to specific questions linked to the damaged building diagnosis and preservation.The comparison of the results obtained by IC, EC and HMC analyses highlights the limits of the EC method in providing quantitative information on soluble salt content. The EC technique seems to require some cautions when used for materials containing other high soluble phases such as portlandite. On the other hand, the HMC technique seems to be very useful in the field of historical masonry investigation since it can provide reliable semi-quantitative distribution of hygroscopic salts.  相似文献   
59.
Witold Kakol 《Thin》1990,10(4):277-297
The stability analysis of stiffened plates by means of the finite strip method is presented. The studies are based on the thin shallow theory, giving nonlinear strain displacement relations, but linear curvature displacement relations. The nonlinear equilibrium equations are obtained by the principle of incremental virtual work, using finite strip discretization. The higher order strip with one internal nodal line is applied. It is shown that considerable improvements can be obtained using this kind of strip. It is especially true for the postbuckling analysis. Numerical examples of the strength of stiffened plates in compression are carried out, covering a range of plate and stiffener slenderness.  相似文献   
60.
The knowledge of interactions between different molecules is undoubtedly the driving force of all contemporary biomedical and biological sciences. Chemical biology/biological chemistry has become an important multidisciplinary bridge connecting the perspectives of chemistry and biology to the study of small molecules/peptidomimetics and their interactions in biological systems. Advances in structural biology research, in particular linking atomic structure to molecular properties and cellular context, are essential for the sophisticated design of new medicines that exhibit a high degree of druggability and very importantly, druglikeness. The authors of this contribution are outstanding scientists in the field who provided a brief overview of their work, which is arranged from in silico investigation through the characterization of interactions of compounds with biomolecules to bioactive materials.  相似文献   
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