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101.
Problem analysis is an important, but mainly neglected part of the problem‐solving process. The theory of inventive problem solving (TRIZ) offers an instrument called function analysis to conduct problem analysis, which is especially useful for exploring a problem. This process is based on an idea applied in different creativity techniques, saying that behind one problem statement many problem formulations may occur, which allows for evaluation and selection of those problem formulations before looking for problem solutions. The application of function analysis as a tool for teams is recommended for a number of reasons. In so doing so, two main questions arise: (i) Should function analysis be used with the help of an external moderator? and: (ii) Should it be applied with currently available special software? After introducing the basics of function analysis this article provides key findings deducted from an experiment addressing these questions. An important result is the remarkable learning effect, which occurs while using function analysis in teams. By applying function analysis in R&D, companies will be able to get deeper and team‐based problem explorations, which may lead to maturing problem solutions.  相似文献   
102.
Sven Axs  ter 《IIE Transactions》1982,14(2):128-130
The dynamic programming solution offered is of complexity O(n2) and is a significant improvement over the implicit enumeration procedure previously suggested by Arora and Rana in an article in the September 1980 issue of TRANSACTIONS.  相似文献   
103.
Ten Philosophical Problems in Belief Revision   总被引:4,自引:0,他引:4  
  相似文献   
104.
A novel liquid-liquid extraction (LLE) procedure was investigated for preparation of peptide and protein samples for matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). LLE using ethyl acetate as the water-immiscible organic solvent enabled segregation of hydrophobic and hydrophilic polypeptides in mixtures, thereby reducing the complexity of mass spectra obtained by MALDI MS. The LLE technique was optimized for rapid and sensitive in situ (on-target) sample preparation for MALDI MS analysis of proteins and peptides at low-picomole and subpicomole levels. Addition of MALDI matrix to the organic solvent enhanced the efficiency of the LLE-MALDI MS method for analysis of hydrophobic peptides and proteins. LLE-MALDI MS enabled the detection of the hydrophobic membrane protein bacteriorhodopsin as a component in a simple protein mixture. Peptide mixtures containing phosphorylated, glycosylated, or acylated peptides were successfully separated and analyzed by the in situ LLE-MALDI MS technique and demonstrate the potential of this method for enhanced separation and structural analysis of posttranslationally modified peptides in proteomics research.  相似文献   
105.
Biofluids, like urine, form very complex matrixes containing a large number of potential biomarkers, that is, changes of endogenous metabolites in response to xenobiotic exposure. This paper describes a fast and sensitive method of screening biomarkers in rat urine. Biomarkers for phospholipidosis, induced by an antidepressant drug, were studied. Urine samples from rats exposed to citalopram were analyzed using solid-phase extraction (SPE) and liquid chromatography mass spectrometry (LC/MS) analysis detecting negative ions. A fast iterative method, called Gentle, was used for the automatic curve resolution, and metabolic fingerprints were obtained. After peak alignment principal component analysis (PCA) was performed for pattern recognition, PCA loadings were studied as a means of discovering potential biomarkers. In this study a number of potential biomarkers of phospholipidosis in rats are discussed. They are reported by their retention time and base peak, as their identification is not within the scope of the study. In addition to the fact that it was possible to differentiate control samples from dosed samples, the data were very easy to interpret, and signals from xenobiotic-related substances were easily removed without affecting the endogenous compounds. The proposed method is a complement or an alternative to NMR for metabolomic applications.  相似文献   
106.
This article describes the fabrication of polymer structures with lateral dimensions in the sub-micron regime using hard X-rays (λc ≈ 0.4 nm) from the electron storage ring ANKA. Spincoated polymethylmethacrylate (PMMA) grades have been analyzed with respect to development rates and contrast. The contrast has been determined to be constant over a wide dose regime but rapidly decreases for dose values below 1 kJ/cm3. Films with a thickness from 2 to 11 μm have been patterned using a high resolution X-ray mask consisting of 2 μm thick gold absorbers on a suspended 1 μm thick silicon nitride membrane. The fabrication of sub-micron X-ray lithography structures with feature sizes down to 400 nm is confined by the mechanical parameters of the resist material and the process conditions. Surface tension after development limits the achievable aspect ratio of isolated pillars and walls, depending on the actual resist height. PMMA structures have been successfully used as template for electroplating of 1 μm thick gold to demonstrate the fabrication capability of sub-micron scale metal parts.  相似文献   
107.
This paper describes model experiments with liquid metals of low melting point as an important tool to investigate the flow structure and related transport processes in melt flows being relevant for metallurgical applications. Three examples have been selected to demonstrate the benefit of such experiments, namely the electromagnetic stirring of a metallic melt in a pool, the directional solidification of Al‐Si alloys under the influence of an electromagnetically driven flow and the behaviour of a liquid metal bubble plume if a vertically travelling field is applied. Results of flow measurements are presented and the relevance for metallurgical processes is discussed.  相似文献   
108.
This study aims to address the paradigms of consumers’ adoption behavior for mobile government, posits the factors which pursue citizens’ intention to adopt mobile government services, and reveals the impact of cultural dimensions in perceiving driving factors of mobile government adoption. The mobile government adoption model was developed and tested among users of three different countries, namely Bangladesh, Canada, and Germany. The finding suggests the rationale that cross-cultural differences impact consumers’ perception of mobile government adoption behavior.  相似文献   
109.
Solid-state nanopores are widely acknowledged as tools with which to study local structure in biological molecules. Individual molecules are forced through a nanopore, causing a characteristic change in an ionic current that depends on the molecules' local diameter and charge distribution. Here, the translocation measurements of long (~5-30 kilobases) single-stranded poly(U) and poly(A) molecules through nanopores ranging from 1.5 to 8 nm in diameter are presented. Individual molecules are found to be able to cause multiple levels of conductance blockade upon traversing the pore. By analyzing these conductance blockades and their relative incidence as a function of nanopore diameter, it is concluded that the smallest conductance blockades likely correspond to molecules that translocate through the pore in predominantly head-to-tail fashion. The larger conductance blockades are likely caused by molecules that arrive at the nanopore entrance with many strands simultaneously. These measurements constitute the first demonstration that single-stranded RNA can be captured in solid-state nanopores that are smaller than the diameter of double-stranded RNA. These results further the understanding of the conductance blockades caused by nucleic acids in solid-state nanopores, relevant for future applications, such as the direct determination of RNA secondary structure.  相似文献   
110.
Incremental model-based estimation using geometric constraints   总被引:1,自引:0,他引:1  
We present a model-based framework for incremental, adaptive object shape estimation and tracking in monocular image sequences. Parametric structure and motion estimation methods usually assume a fixed class of shape representation (splines, deformable superquadrics, etc.) that is initialized prior to tracking. Since the model shape coverage is fixed a priori, the incremental recovery of structure is decoupled from tracking, thereby limiting both processes in their scope and robustness. In this work, we describe a model-based framework that supports the automatic detection and integration of low-level geometric primitives (lines) incrementally. Such primitives are not explicitly captured in the initial model, but are moving consistently with its image motion. The consistency tests used to identify new structure are based on trinocular constraints between geometric primitives. The method allows not only an increase in the model scope, but also improves tracking accuracy by including the newly recovered features in its state estimation. The formulation is a step toward automatic model building, since it allows both weaker assumptions on the availability of a prior shape representation and on the number of features that would otherwise be necessary for entirely bottom-up reconstruction. We demonstrate the proposed approach on two separate image-based tracking domains, each involving complex 3D object structure and motion.  相似文献   
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