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101.
Journal of Materials Science: Materials in Electronics - Adapting the solution growth method, l-cysteine cadmium chloride (LCC) crystal was synthesized, and by using a single-crystal X-ray...  相似文献   
102.
High-resolution images can be used to resolve matching ambiguities between trajectory fragments (tracklets), which is a key challenge in multiple-target tracking. A pan–tilt–zoom (PTZ) camera, which can pan, tilt and zoom, is a powerful and efficient tool that offers both close-up views and wide area coverage on demand. The wide area enables tracking of many targets, while the close-up view allows individuals to be identified from high-resolution images of their faces. A central component of a PTZ tracking system is a scheduling algorithm that determines which target to zoom in on, particularly when the high-resolution images are also used for tracklet matching. In this paper, we study this scheduling problem from a theoretical perspective. We propose a novel data structure, the Multi-strand Tracking Graph (MSG), which represents the set of tracklets computed by a tracker and the possible associations between them. The MSG allows efficient scheduling as well as resolving of matching ambiguities between tracklets. The main feature of the MSG is the auxiliary data saved in each vertex, which allows efficient computation while avoiding time-consuming graph traversal. Synthetic data simulations are used to evaluate our scheduling algorithm and to demonstrate its superiority over a naïve one.  相似文献   
103.
Networks distribute energy, materials and information to the components of a variety of natural and human-engineered systems, including organisms, brains, the Internet and microprocessors. Distribution networks enable the integrated and coordinated functioning of these systems, and they also constrain their design. The similar hierarchical branching networks observed in organisms and microprocessors are striking, given that the structure of organisms has evolved via natural selection, while microprocessors are designed by engineers. Metabolic scaling theory (MST) shows that the rate at which networks deliver energy to an organism is proportional to its mass raised to the 3/4 power. We show that computational systems are also characterized by nonlinear network scaling and use MST principles to characterize how information networks scale, focusing on how MST predicts properties of clock distribution networks in microprocessors. The MST equations are modified to account for variation in the size and density of transistors and terminal wires in microprocessors. Based on the scaling of the clock distribution network, we predict a set of trade-offs and performance properties that scale with chip size and the number of transistors. However, there are systematic deviations between power requirements on microprocessors and predictions derived directly from MST. These deviations are addressed by augmenting the model to account for decentralized flow in some microprocessor networks (e.g. in logic networks). More generally, we hypothesize a set of constraints between the size, power and performance of networked information systems including transistors on chips, hosts on the Internet and neurons in the brain.  相似文献   
104.
The present work aimed at evaluating the Cucurbita maxima Duchesne defatted seeds flour (CDSF) as fat replacer in beef patty. Pastes obtained from CDSF containing 60 and 72 % water were prepared and used to replace fat in beef patty at 25, 50, 75 and 100 % respectively. A control patty was processed using kidney fat from beef. The proximate composition, technological yield, textural and sensorial properties of different samples were evaluated. Results showed that CDSF contains 77.76/100 g proteins based on dried matter. Protein content of patty increased with fat substitution rates (FSR) from 18.82/100 g wet matter (WM) to 23.24/100 g WM respectively for the control (P0) and the sample in which fat was substituted at 100 % with the CDSF paste with a water content of 60 % (P460). The lipid content dropped with the increase in the fat substitution rate and water content of CDSF paste from 10.70/100 to 0.28/100 g WM respectively for the sample in which fat was substituted at 25 % with the CDSF paste with a water content of 60 % (P160) and the sample in which fat was substituted at 100 % with the CDSF paste containing 72 % water (P472). Similarly, hardness dropped from 54.78 N (P0) to 37.56 N (P472) respectively. The cooking yield increased significantly (p < 0.05) with the increase in the water content of the CDSF paste and the fat substitution rate. From the sensory analysis, patties with 75 and 100 % of FSR were the most accepted. Thus, the CDSF paste can be used in beef patty as a fat replacer to reduce the detrimental effect of animal fat consumption.  相似文献   
105.
One approach to recognizing objects seen from arbitrary viewpoint is by extracting invariant properties of the objects from single images. Such properties are found in images of 3D objects only when the objects are constrained to belong to certain classes (e.g., bilaterally symmetric objects). Existing studies that follow this approach propose how to compute invariant representations for a handful of classes of objects. A fundamental question regarding the invariance approach is whether it can be applied to a wide range of classes. To answer this question it is essential to study the set of classes for which invariance exists. This paper introduces a new method for determining the existence of invariant functions for classes of objects together with the set of images from which these invariants can be computed. We develop algebraic tests that determine whether the objects in a given class can be identified from single images. These tests apply to classes of objects undergoing affine projection. In addition, these tests allow us to determine the set of views of the objects which are degenerate. We apply these tests to several classes of objects and determine which of them is identifiable and which of their views are degenerate.  相似文献   
106.
Dynamic tank in series modeling of direct internal reforming SOFC   总被引:1,自引:0,他引:1       下载免费PDF全文
A dynamic tank in series reactor model of a direct internally reforming solid oxide fuel cell is presented and validated using experimental data as well as a computational fluid dynamics (CFD) model for the spatial profiles. The effect of the flow distribution pattern at the inlet manifold on the cell performance is studied with this model. The tank in series reactor model provides a reasonable understanding of the spatio‐temporal distribution of the key parameters at a much lesser computational cost when compared to CFD methods. The predicted V–I curves agree well with the experimental data at different inlet flows and temperatures, with a difference of less than ±1.5%. In addition, comparison of the steady‐state results with two‐dimensional contours from a CFD model demonstrates the success of the adopted approach of adjusting the flow distribution pattern at the inlet boundaries of different continuous stirred tank reactor compartments. The spatial variation of the temperature of the PEN structure is captured along with the distributions of the current density and the anode activation over‐potential that strongly related to the temperature as well as the species molar fractions. It is found that, under the influence of the flow distribution pattern and reaction rates, the dynamic responses to step changes in voltage (from 0.819 to 0.84 V), fuel flow (15%) and temperature changes (30 °C), on anode side and on cathode side, highly depend on the spatial locations in the cell. In general, the inlet points attain steady state rapidly compared to other regions. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
107.
108.
The effect of natural-fermentation and roasting on maize physicochemical and functional properties were evaluated. Natural fermented maize seeds were soaked for variable times (0, 24 and 48 h) and directly decorticated or roasted before milling into flour. Generally during the 24 to 48 h natural fermentation, total sugars (80.3–92.0 g/100 g) and proteins contents (4.0–7.6 g/100 g) decreased while they significantly increased with soaking. Soluble sugars content of the unroasted maize significantly decreased with fermentation while that of roasted maize significantly increased. Reverse observations were made on soluble proteins. The antinutrients (phytates and total polyphenols) contents of the grains as well as the functional properties of their flours were observed to have been significantly changed following fermentation and roasting. In particular the least gelation concentration (6 to 18 g/100 mL), an important reverse index of gelating power significantly increased with fermentation and roasting. As consequence the viscosity of the fermented maize flours were systematically significantly lower than that of the unfermented flour. Generally while the effects of duration of fermentation and roasting on the viscosity were not consistent, the 48 h natural fermented and roasted flour was observed to particularly produce flours of much lower viscosity. This highlighted the positive effect of combining fermentation and roasting to improve the quality of weaning flour made from maize.  相似文献   
109.
The functionality of the plasma antenna has been narrowed to types and brand names only.The physics of its operation has been neglected and has stagnated technological innovations.The magnetic field in the sheath and plasma were investigated.Notable specifications were worked out in the proposed improved cylindrical monopole plasma antenna.The occurrence of femto spin demagnetization was discovered between the duration of switch on and switch off of the antenna.This phenomenon seems transient because magnetization is highest at the switch on/off point.  相似文献   
110.
We report on infrared (IR) spectromicroscopy of the electronic excitations in nanometer-thick accumulation layers in field-effect transistor (FET) devices based on poly(3-hexylthiophene). IR data allows us to explore the charge injection landscape and uncovers the critical role of the gate insulator in defining relevant length scales. This work demonstrates the unique potential of IR spectroscopy for the investigation of physical phenomena at the nanoscale occurring at the semiconductor-insulator interface in FET devices.  相似文献   
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