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151.
Huang W  Shen S  Nimalaratne C  Li S  Majumder K  Wu J 《Food chemistry》2012,135(3):1600-1607
Ovotransferrin-derived peptides showed synergistic effects with vitamin C, epigallocatechin gallate (EGCG), and caffeic acid, but not quercetin in our previous report. In this study, we further investigated the interactions between ovotransferrin-derived peptides and teas, based on the oxygen radical absorbance capacity (ORAC) assay. Our results showed that there was no significant difference in ORAC values among green, oolong, and black teas. For all the samples, 80% methanol extracts possessed better antioxidant capacity than hot water extracts. The antioxidant capacity of teas were improved by adding either ovotransferrin hydrolysate or its purified peptide IRW; however, adding hydrolysate did not improve antioxidant stability of teas. ORAC values of both teas and hydrolysate added teas were decreased during 22weeks of storage, while samples stored at 4°C exhibited higher antioxidant capacity than those stored at room temperature. This suggested that ovotransferrin hydrolysate could be used as functional food ingredients in enhancing antioxidant capacities of foods, which would benefit human nutrition and health.  相似文献   
152.
A simple theoretical analysis for evaluating the performance of linecoded optical frequency shift keying (FSK) systems is presented. It accounts for the combined effects of laser phase noise, receiver noise, and nonuniform BM response of distributed feedback lasers. A close form expression for the random frequency noise due to the combined effect of laser nonuniform FM response and phase noise is developed. The analysis is carried out for three different linecoding schemes, i.e., alternate mark inversion, Miller code or delay modulation, and Manchester coding, to investigate the efficacy of the line coding schemes in counteracting the effect of nonflat FM response. Theoretical and simulation results show that the sensitivities of linecoded FSK systems are within 0.7 and 0.4 dB for single-branch and dual-branch detection, respectively, at a bit error probability of 10-9 relative to the random non-return to zero FSK with flat FM response  相似文献   
153.
Two reference points of a region are defined which do not depend on the position, size and orientation of the region. Reference points are used to get borders on the basis of which the shape distance and shape similarity are defined.  相似文献   
154.
The optical return-to-zero differential phase-shift keying system is analyzed to determine the accuracy of the differential phase Q method in estimating the bit-error rate (BER). It is found that it consistently underestimates the BER though it successfully predicts the qualitative behavior of single-channel and wavelength-division-multiplexed systems for back-to-back and point-to-point configurations. A simple modification reduced the underestimation and produced accurate results.  相似文献   
155.
The investigation studied the optimal fertilizer rates and mixtures for maximum production of smooth cayenne pineapples in the tropical ferrallitic soil.Fertilized pineapples were significantly (P = 0.05) superior in growth and fruit yield to the unfertilized control. Nitrogen and potassium were the most critical nutrients. Nitrogen deficiency manifested within 6 months of planting as reduced, thorny and pink coloured leaves resulting in over 10 months delayed plant crop harvest and over 38% reduction in fruit yield. Less than 20% of pineapples which lacked nitrogen remained productive during the first ratoon crop. However, when nitrogen was increased twofold (100 to 200 kg/ha/year), the fruit of the plant crop doubled with 15-10% increased fruit lodging. Potassium significantly (P = 0.05) reduced fruit lodging and improved fruit yield and flavour.Nitrogen further enhanced the effective utilization of P and K for significant yield increases. Thus, the interaction between high nitrogen (200 kg/ha/year) and low phosphorus (50 kg/ha) or high potassium (200 kg/ha) respectively, significantly (P = 0.05) increased the yield of pineapples, while P and K interaction retarded growth, delayed crop maturity and reduced the fruit yield and quality. Pineapples which received fertilizer mixture of NPK 200-50-200 produced the highest and best quality fruits and was therefore recommended for optimum yield of pineapples in the tropical ferrallitic soils.  相似文献   
156.
Any image processing technique which is used to improve the appearance of an image for human perception or machine analysis should incorporate the characteristics of the human visual system. One of the major characteristics of the human visual system is the logarithmic response to light intensity, which we have attempted to include in this paper. Some new algorithms for image enhancement, edge detection and smoothing have been described and their results are presented. Only the edge detection technique is space-variant. All the techniques are simple and economical, and can be supplied to each pixel in parallel.  相似文献   
157.

The conventional Butterfly Optimization Algorithm (BOA) does not appropriately balance the exploration and exploitation characteristics of an algorithm to solve present-day challenging optimization problems. For the same, in this paper, a novel hybrid BOA (MPBOA, in short) is suggested, where the BOA is combined with mutualism and parasitism phases of the Symbiosis Organisms Search (SOS) algorithm to enhance the search behaviour (both global and local) of BOA. The mutualism phase is applied with the global phase of BOA, and the parasitism phase is added with the local phase of BOA to ensure a better trade-off between the global and local search of the proposed algorithm. A suit of twenty-five benchmark functions is employed to investigate its performance with several other state-of-the-art algorithms available in the literature. Also, to check its performance statistically, the Friedman rank test and t-test are carried out. The consistency of the proposed algorithm is tested with a boxplot diagram. Also, four real-world problems are solved to check the efficiency of the algorithm in solving industrial problems. Finally, the proposed MPBOA is utilized to obtain the optimal threshold in the multilevel thresholding problem of the segmentation of individual images. From the obtained results, it is found that the overall performance of the newly introduced MPBOA is satisfactory in terms of its search behaviour and convergence time to obtain global optima.

  相似文献   
158.
Centralized techniques have been used until now when automatically calibrating (both geometrically and photometrically) large high-resolution displays created by tiling multiple projectors in a 2D array. A centralized server managed all the projectors and also the camera(s) used to calibrate the display. In this paper, we propose an asynchronous distributed calibration methodology via a display unit called the plug-and-play projector (PPP). The PPP consists of a projector, camera, computation and communication unit, thus creating a self-sufficient module that enables an asynchronous distributed architecture for multi-projector displays. We present a single-program-multiple-data (SPMD) calibration algorithm that runs on each PPP and achieves a truly scalable and reconfigurable display without any input from the user. It instruments novel capabilities like adding/removing PPPs from the display dynamically, detecting faults, and reshaping the display to a reasonable rectangular shape to react to the addition/removal/faults. To the best of our knowledge, this is the first attempt to realize a completely asynchronous and distributed calibration architecture and methodology for multi-projector displays.  相似文献   
159.
The evolution of 5th Generation wireless technology introduced Mobile Edge Computing, where edge servers are placed at the edge of the network, and are associated with evolved Node Base Stations (eNBs). This enables mobile users to offload their resource‐intensive tasks to these servers and improve network performance by reducing end‐to‐end delay. However, frequent user mobility leads to frequent re‐planning of network and increases network load. This demands dynamic Virtual Machine (VM) migration in Mobile Edge paradigm for an improved Quality of Service (QoS). For an enhanced VM migration process, an optimal pair of migrating VMs and destination edge servers needs to be chosen. In this paper, we propose an optimized decision‐making policy that chooses such optimal pairs. Several decision parameters such as average wait time, processing delay, migration delay, transmission power, and processing power are modeled. A profit function is developed using these modeled decision parameters that chooses the optimal pairs. This function is maximized using the proposed hybrid evolutionary algorithm, which combines the advantages of PSO and GA. The pairs are chosen in such a manner, that the selection guarantees high network throughput, reduced service delay, and energy consumption which is reflected in the simulation.  相似文献   
160.
In portfolio selection problem, the expected return, risk, liquidity etc. cannot be predicted precisely. The investor generally makes his portfolio decision according to his experience and his economic wisdom. So, deterministic portfolio selection is not a good choice for the investor. In most of the recent works on this problem, fuzzy set theory is widely used to model the problem in uncertain environments. This paper utilizes the concept of interval numbers in fuzzy set theory to extend the classical mean–variance (MV) portfolio selection model into mean–variance–skewness (MVS) model with consideration of transaction cost. In addition, some other criteria like short and long term returns, liquidity, dividends, number of assets in the portfolio and the maximum and minimum allowable capital invested in stocks of any selected company are considered. Three different models have been proposed by defining the future financial market optimistically, pessimistically and in the combined form to model the fuzzy MVS portfolio selection problem. In order to solve the models, fuzzy simulation (FS) and elitist genetic algorithm (EGA) are integrated to produce a more powerful and effective hybrid intelligence algorithm (HIA). Finally, our approaches are tested on a set of stock data from Bombay Stock Exchange (BSE).  相似文献   
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