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991.
Standardized business documents are a prerequisite for successful information exchange in electronic business transactions. The United Nations Centre for Trade Facilitation and eBusiness (UN/CEFACT) provides a conceptual modeling approach, called Core Components, used by Business Partners (BPs) for defining business document models (BDMs). BDMs are essential for defining service interfaces in service-oriented systems. However, in such a highly dynamic environment with ever-changing market demands, BPs are confronted with the need to revise their BDMs resulting in a multitude of different versions. BPs may dictate the use of new versions of BDMs, but small- and medium-sized enterprises (SMEs) may not always adopt new BDM versions due to the cost and effort involved, inhibiting automated electronic information exchange. In this article, we propose a framework including (i) a classification of the impact of changes in BDMs, (ii) evolution templates for the automated transformation of business documents between different BDM versions, and (iii) mitigation strategies for evolutions where fully-automated and semantic-preserving transformations are not feasible. Having such a framework at hand provides SMEs with a low-cost and light-weight approach for dealing with evolving market requirements and hence evolving business documents. Finally, we analyze the evolution of UN/CEFACT''s Cross Industry Invoice which has been mandated to be used for electronic invoicing within the European Union as well as present a critical discussion of the evolution templates defined.  相似文献   
992.
Prime pictures of emotional scenes appeared in parafoveal vision, followed by probe pictures either congruent or incongruent in affective valence. Participants responded whether the probe was pleasant or unpleasant (or whether it portrayed people or animals). Shorter latencies for congruent than for incongruent prime-probe pairs revealed affective priming. This occurred even when visual attention was focused on a concurrent verbal task and when foveal gaze-contingent masking prevented overt attention to the primes but only if these had been preexposed and appeared in the left visual field. The preexposure and laterality patterns were different for affective priming and semantic category priming. Affective priming was independent of the nature of the task (i.e., affective or category judgment), whereas semantic priming was not. The authors conclude that affective processing occurs without overt attention--although it is dependent on resources available for covert attention--and that prior experience of the stimulus is required and right-hemisphere dominance is involved. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
993.
This part of the volume contains the papers accepted for presentation at the workshop on Unification in Non-Classical Logics (UNCL), co-located with ICALP 2002, which took place on July 12, 2002 in M 'alaga, Spain.The workshop was concerned with one of the most promising areas of research on non-classical logics and its applications. Unification in non-classical logics, with various approaches to handling generalised terms, has drawn more and more attention in recent years. So far, most popular lines of research include fuzzy unification of (conventional) databases and the use of fuzzy concepts in information retrieval.This workshop was conceived as a forum for the exchange of ideas relevant for the concept of unification in non-classical logics, including, but not limited to, the topics of:
• Unification in multiple-valued and fuzzy logic programming.
• Unification based on similarities and fuzzy equivalence relations.
• Categorical unification.
• Practical use of non-classical unification, e.g. in expert systems and information retrieval.
The program committee selected six papers after a reviewing process in which each submitted paper received at least two reviews. Considerable effort was devoted for the evaluation of the submissions and to providing the authors with helpful feedback. The criteria for selection were originality, quality, and relevance to the topic of the workshop.Alsinet et al reviewed and compared two models which extend first order possibilistic logic in order to enable fuzzy unification. The extension considers mainly fuzzy constants, and in form of restrictions on existential quantifiers.Banerjee and Bujosa presented a non-classical interpretion of classical unification in terms of geometrical constructions over a suitable R-module M. The main result is that unification of two terms can be seen as the intersection of their corresponding affine varieties on M. This paves the way of using methods from computer algebra in the field of unification.In Eklund et al, substitutions and unifiers appear as constructs in Kleisli categories related to particular composed powerset term monads. It is shown that an often used similarity-based approach to fuzzy unification is compatible with the categorical approach, and can be adequately extended.Kutsia presented a unification procedure for a theory with individual and sequence variables, free fixed and flexible arity function symbols and patterns. These theories have been used in different contexts such as databases, rewriting, programming languages, or theorem proving.Medina et al introduced a formal model for similarity-based fuzzy unification in multi-adjoint logic programs. On this computational model, a similarity-based unification approach which provides a semantic framework for logic programming with different notions of similarity was constructed.Virtanen introduced unification in similarity-based logic programming. One of the crucial points is the definition of similarity degrees between sets, giving rise to [lambda]-interpretations. The selection of so called most significant terms again is one of the cornerstones of the paper.We would like to thank all those who submitted papers for consideration, the authors of accepted papers for their interesting discussions during the workshop, the additional referees for their careful work, and Inma Fortes from the local organising committee for her assistance.  相似文献   
994.
This paper presents the theoretical support and experimental results of the application of advanced and intelligent control techniques to the drive control and trajectory tracking systems on a robotic wheelchair. The adaptive optimal control of the differential drive helps to improve the automatic guidance system's safety and comfort taking into consideration operating conditions such as load and distribution changes or motion actuator limitations. Furthermore, the incorporation of an optimal controller to minimize location errors and a fuzzy controller to adapt the linear velocity to the characteristics of the trajectory, provide the vehicle with a high degree of intelligence and autonomy, even when faced with obstacles. The global control solution implemented increases the features of the wheelchair for handicapped people, especially for those with a high degree of disability.  相似文献   
995.
The potential of controlled rate thermal analysis (CRTA) for studying high-pressure gas-solid processes has been evaluated. CRTA is a type of smart temperature program based on a feedback system that uses any experimental signal related to the process evolution for commanding the temperature evolution. In this work, an instrument that uses the gravimetric signal for CRTA control has been designed and used for the study of two high-pressure gas-solid reactions: the highly exothermic thermal oxidation of TiC under high pressure of oxygen and the reduction in Fe2O3 under high pressure of hydrogen. Advantages of CRTA for discriminating overlapping processes and appraising kinetic reaction mechanisms are shown.  相似文献   
996.
Rheological properties of polymer–camphene solutions are very relevant as they affect their stability, and they have many implications in operation costs. This work elucidates the rheological properties of polystyrene (PS–camphene) solutions with industrial applications. Unfortunately, the assessment of the very low shear viscosities of camphene-based materials (below 0.005 Pa s) is still a challenge with commercial rheometers. Flow curves, stress growth tests, and small amplitude oscillatory shear (SAOS) measurements were carried out as a function of PS concentration (0, 2.5, 5.0, 10, and 20 wt % PS) to understand the rheological behavior of these systems. Results indicate that liquid camphene has a shear-thinning behavior (flow index = 0.99) when the increase of polymer concentration involves changes in the structure of these systems (flow index = 0.10 for 20 wt % PS). An increase in PS concentration leads to a forwarding in the shear-thinning zone, and the Newtonian region (from ∼1 s−1, for 0 wt % PS, to 10−3 s−1 for 20 wt % PS). Eventually, these results evidence the high dependence of η on PS concentration (from ∼1.16 ± 0.01 Pa s, for 0 wt % PS, to 631.5 ± 0.2 Pa s for 20 wt % PS). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47953.  相似文献   
997.
The Journal of Supercomputing - Understanding I/O for data-intense applications is the foundation for the optimization of these applications. The classification of the applications according to the...  相似文献   
998.
Steam sterilization processes rely on high heat transfer rates from the steam to the medical devices. To guarantee this, all non‐condensable gases (NCGs) must be removed from the steam sterilizer before sterilization. The ratios and distribution of the NCGs in the pre‐sterilization phases of both a vacuum and a non‐vacuum steam sterilizer are investigated. Two CFD models for simulation of the NCGs in the sterilizers were developed and validated by the measurements of a pressure sensor and eight thermocouples inside the steam sterilizer. Furthermore, a novel method was developed to calculate the real ratio of NCGs based on the standard measurement (EN 13060). The results show that the NCGs ratio defined in the EN 13060 did not accurately represent the real ratios of the NCGs.  相似文献   
999.
Halloysite nanotubes (HNTs) have attracted a technologic and scientific attention as reinforcements of epoxy-based nanocomposites. However, their reported interaction with epoxy matrices is varied and the controlled dispersion of HNTs is still a challenge. In this work, we study the effect of chemical reactions taking place in the dispersion process of halloysite and their possible influence in the composite's properties. HNTs' surface was modified through an alkaline treatment and by grafting two aminosilanes with different chain lengths and functionality numbers. Evidence of homopolymerization and degradation reactions was found, depending on the surface treatment. The rheological study indicated that an interconnected network can be achieved in epoxy/HNTs blends depending on the surface chemical characteristics of the nanofillers and the blending method. The better dispersion was accomplished when ultrasonicating with the aid of a solvent. Nevertheless, the mechanical properties of the nanocomposites are not warranted by selecting a dispersion method. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47979.  相似文献   
1000.
Many critical aspects affect the correct operation of a Brain Computer Interface. The term ‘BCI-illiteracy’ describes the impossibility of using a BCI paradigm. At present, a universal solution does not exist and seeking innovative protocols to drive a BCI is mandatory. This work presents a meta-analytic review on recent advances in emotions recognition with the perspective of using emotions as voluntary, stimulus-independent, commands for BCIs. 60 papers, based on electroencephalography measurements, were selected to evaluate what emotions have been most recognised and what brain regions were activated by them. It was found that happiness, sadness, anger and calm were the most recognised emotions. Relevant discriminant locations for emotions recognition and for the particular case of discrete emotions recognition were identified in the temporal, frontal and parietal areas. The meta-analysis was mainly performed on stimulus-elicited emotions, due to the limited amount of literature about self-induced emotions. The obtained results represent a good starting point for the development of BCI driven by emotions and allow to: (1) ascertain that emotions are measurable and recognisable one from another (2) select a subset of most recognisable emotions and the corresponding active brain regions.  相似文献   
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