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81.
This paper presents experiences and lessons learned during the introduction of Building Information Models (BIM) in construction engineering project management courses. We illustratively show that the introduction of BIM-based project management tools helped the teachers of two courses to develop more realistic project-based class assignments that supported students with learning how to apply different formal project management methods to real-world project management problems. In particular, we show that the introduction of BIM allows educators to design a class project that allowed the use of more realistic cases that better simulate real-world project conditions, helped students to learn how different project management methods integrate with each other, integrate change management tasks in a class assignment, and learn how to optimize project plans.  相似文献   
82.
Social manufacturing (SM), a novel distributed, collaborative and intelligent manufacturing mode, is proposed and developed for high-end apparel customization. The main components of SM cloud are designed, and its research topics are summarized. Then, SM's key technologies are studied. 3D technologies for apparel customization, like 3D modeling, 3D fitting mirror and 3D customization, are developed to improve the customization precision and user experience. Information based collaborative management is realized to share, communicate, and handle the information efficiently among all groups and individuals of SM cloud. Suppliers' evaluation mechanism is designed to support the optimal decisions making. Next, SM cloud is constructed in five layers for high-end apparel customization. By using SM cloud based crowd-sourcing, social resources can be allocated rationally and utilized efficiently, consumer can customize the product in any processes like innovation, design, making, marketing and service, and traditional apparel enterprise can be upgraded into SM mode for keeping it competitive in the future customization markets.   相似文献   
83.
We propose a method for rendering volumetric data sets at interactive frame rates while supporting dynamic ambient occlusion as well as an approximation to color bleeding. In contrast to ambient occlusion approaches for polygonal data, techniques for volumetric data sets have to face additional challenges, since by changing rendering parameters, such as the transfer function or the thresholding, the structure of the data set and thus the light interactions may vary drastically. Therefore, during a preprocessing step which is independent of the rendering parameters we capture light interactions for all combinations of structures extractable from a volumetric data set. In order to compute the light interactions between the different structures, we combine this preprocessed information during rendering based on the rendering parameters defined interactively by the user. Thus our method supports interactive exploration of a volumetric data set but still gives the user control over the most important rendering parameters. For instance, if the user alters the transfer function to extract different structures from a volumetric data set the light interactions between the extracted structures are captured in the rendering while still allowing interactive frame rates. Compared to known local illumination models for volume rendering our method does not introduce any substantial rendering overhead and can be integrated easily into existing volume rendering applications. In this paper we will explain our approach, discuss the implications for interactive volume rendering and present the achieved results.  相似文献   
84.
Summary The purpose of this study is to quantify and compare the publication and citation output of the biggest faculties of economics and social sciences in Germany. Various publication and citation measures based upon Social Science Citation Index (SSCI) data are used to explore the comparative strengths and weaknesses of ten academic fields at the named faculties. To reflect the varying size of the fields and faculties, output measures as well as productivity measures are explicitly considered. From a bibliometric perspective empirical results demonstrate that various measures are necessary to adequately identify the comparative strengths and weaknesses of entire faculties and of selected disciplines within faculties.  相似文献   
85.
Incremental constraint modelling in a feature modelling system   总被引:1,自引:0,他引:1  
The techniques of constraint propagation have recently been successfully applied to feature-based design. Because of their speed, constraint propagation methods allow incremental design and rapid local modifcations of the part. However, cyclic constraints cause serious problems to current constraint propagation algorithms. Variational geometric design systems can, in principle, manage these cases. Unfortunately, this typically requires complete re-evaluation of the underlying set of constraint equations, making the method unsuitable for interactive use. The proposed system aims to localize the problem of constraint solving and maintenance. The constraint graph of the part or assembly is divided into several independent partial graphs, subsystems. Afterwards, each subsystem is handled separately using a selected constraint solving technique for the subsystem.  相似文献   
86.
The actor-partner interdependence model was used to test whether one parent's depressive vulnerability (self-criticism and dependency) was associated with the same parent's own (an intraparental association) and the other parent's (a cross-parental association) ratings of their 5-year-old child's temperament (536 parents, 268 dyads). The more vulnerable the parents were, the more the children showed negative affectivity and lack of effortful control. Significant interactions with the parent's gender and between the spouses' depressive vulnerabilities were found, highlighting the fact that child outcomes are dependent on family processes. All associations were independent of maternal and paternal depressive symptoms. The influence of personality-based depressive traits on child temperamental outcomes and effective parenting is discussed with reference to between-dyad family dynamics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Rhodamine B (RhB) exhibits strong cathodic electrogenerated chemiluminescence (ECL) in aqueous solutions during high-amplitude pulse polarization at thin oxide film-coated aluminum electrodes. This method allows the detection of RhB below nanomolar concentration level and provides linear calibration plots spanning over several orders of magnitude of concentration. In addition, a relatively long ECL lifetime of RhB provides a basis for time-resolved detection. Thus, widely used RhB-based labels can also be suggested to be usable as electrochemiluminescent labels in fully aqueous solutions in bioaffinity assays such as in immunoassays and DNA-probing assays. Support was obtained for the chemiluminescence generation mechanism to be essentially the same as that of radiochemiluminescence in aqueous solution.  相似文献   
88.
Cobalt salen-type [salen=N,N′-bis(salicylidene)ethylenediamine] complexes 1–6 were studied as catalysts for dioxygen activation in the oxidation of veratryl alcohol in basic aqueous conditions. The complexes Co(salen) (1), Co(CH3salen) (2) [CH3salen=N,N′-bis(methylsalicylidene)ethylenediamine], Co(4OHsalen) (3) [4OHsalen=N,N′-bis(4-hydroxosalicylidene)ethylenediamine], Co(sulfosalen) (4) [sulfosalen=N,N′-bis(5-sulfonatosalicylidene)ethylenediamine], Co(acacen) (5) [acacen=N,N′-bis(acetylacetone)ethylenediamine) and Co(N-Me-salpr) (6) [N-Me-salpr=bis(salicylideniminato-3-propyl)methylamine] were chosen to examine the influence of ligand structure on the catalytic activity. The effect of reaction conditions on the oxidation of veratryl alcohol was studied by varying temperature, pH, time or the nature and amount of the axial base needed to enhance the activity of complexes 1–5. The catalytic behaviour of the studied complexes was shown to be very depended on the applied conditions and distinct differences could be observed among the complexes. In all reactions, veratraldehyde was the only product observed. The unsubstituted complex 1 was the most efficient catalyst in the studied system achieving turnover numbers of up to 28 at 80 °C and pH 12.5.  相似文献   
89.
The effect of metallurgical variables on the two most important crack growth mechanisms - stable crack growth by environmentally assisted cyclic crack growth and unstable crack growth by cleavage - in light water reactor pressure vessel steels is evaluated. The analyses are based on micromechanisms of fracture and sensitivity analysis, when applicable. Metallurgical variables considered are non-metallic inclusions and carbides as well as other parameters through their effects on yield strength and other mechanical properties.  相似文献   
90.
A cleanup method was developed to remove coextracted lipids and natural hormones from biota samples in order to test the endocrine-disrupting (ED) capacity of their extracts in in vitro bioassays. Unspiked and spiked fish tissues were cleaned with a combination of dialysis, gel permeation chromatography (GPC), and normal-phase liquid chromatography (NP-HPLC). The spiking mixture consisted of a broad range of environmental pollutants (endocrine disruptors and genotoxic compounds). Chemical recoveries of each test compound, and thyroid-hormone-like and (anti)androgenic activities of the cleaned extracts were investigated. Despite the chemical and toxicological complexity of the spiking mixture and the sequential sample treatment, chemical analysis revealed acceptable recoveries on average: 89 ± 8% after each cleanup step separately and 75 ± 3% after the whole extraction and cleanup procedure in the extracts. In addition, recovered activities in the bioassays were in good agreement with the spiking levels. The developed cleanup method proved to be capable of lipid and natural hormone removal from fish extracts, enabling the measurement of selected endocrine-hormone-like activities in T(4)*-TTR and AR-CALUX bioassays. The method can be used as a sample preparation method of biota samples for toxicity profiling and effect-directed analysis (EDA).  相似文献   
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