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61.
Image processing is an important stage of every microarray experiment. Reliability of this stage strongly influences the results of data analysis performed on extracted gene expressions. Multiple methods related to array recognition, spot segmentation and measurement extraction have emerged in this area over past several years. Currently there are various commercial and freeware packages available, which perform microarray image analysis. This paper attempts to review microarray image analysis as a whole and to make some experimental comparison of several computational schemes for signal segmentation and measurement extraction. Also we provide a detailed discussion of automated image quality control for use with microarray images.  相似文献   
62.
The optimal utilization of multiple combined heat and power (CHP) systems is a complex problem. Therefore, efficient methods are required to solve it. In this paper, a recent optimization technique, namely mesh adaptive direct search (MADS) is implemented to solve the combined heat and power economic dispatch (CHPED) problem with bounded feasible operating region. Three test cases taken from the literature are used to evaluate the exploring ability of MADS. Latin hypercube sampling (LHS), particle swarm optimization (PSO) and design and analysis of computer experiments (DACE) surrogate algorithms are used as powerful SEARCH strategies in the MADS algorithm to improve its effectiveness. The numerical results demonstrate that the utilized MADS–LHS, MADS–PSO, MADS–DACE algorithms have acceptable performance when applied to the CHPED problems. The results obtained using the MADS–DACE algorithm are considerably better than or as well as the best known solutions reported previously in the literature. In addition to the superior performance, MADS–DACE provides significant savings of computational effort.  相似文献   
63.
In the deregulated power environment, including Central operator (CO) and Micro Grids (MGs), different parts of the network are dedicated to the private sector, and each of them seeks to increase their profits independently. The CO and MGs should cooperate and collaborate in terms of operating, security and reliability in the whole power system. This article proposes a new method based on a System of System (SoS) concept for the secure and economic hourly generation scheduling to find optimal operational point. The main methodology includes three steps. In the first step, the power system is divided into several subsystems by using a spectral clustering partitioning technique to reduce converge time by decentralizes methods. And also load forecasting based on a Gaussian probability distribution function to avoid conventional calculation and considering uncertainty of the loads has been presented. To find a similar scenario, and reduction scenario with low probability, the probabilistic method has been addressed. The main contribution of this method is removing scenarios with low value of probabilities and scenarios which are similar to each other. In fact, the reduced set must include scenarios which are scattered appropriately in the uncertain space while holding high probabilities. In order to estimate the similarity (distance) between two scenarios the Kantorovich distance is implemented. In the second step, the hierarchical Bi‐level optimization approach is used to execute the decentralized decision making to solve the Security Constraints Unit Commitment (SCUC) problem between CO and MGs. Regarding all physical relations and shared data among CO and MGs, the SoS concept and Bi‐level optimization are presented to find the optimal operating point of autonomous systems. In the third step, a random number of generators will be select. Hence, the initial iteration number is set. In this step, sampling from state space to classifying reliability object achieved (The expected energy not supplied and loss of load probability are the reliability criterion). The presented method is evaluated using a 6‐bus, the RTS 24‐bus, 118‐bus, and 4672‐bus as an IEEE test systems. The suggested structure has been implemented by GAMS, and the results illustrate the usefulness of the presented methodology. To comparing proposed approach with the centralized method, the results illustrate improving total operational costs and security (in RTS‐24($603,209), 118 bus ($2 562 154) and 4672‐bus ($9 185 168)) in scenario 3 near to 9%, 10% and 8% respectively. Similarly, by comparison (in three test systems) with genetic algorithm these improvements are near to 23%, 22% and 13% respectively.  相似文献   
64.
Present study evaluated the catalytic steam gasification of furniture waste to enhance the biohydrogen production. To do this, 10 wt% nickel loaded catalysts on the variety of supports (Al2O3, CeO2, CeO2-La2O3, and CeO2–ZrO2) were prepared by the novel solvent deficient method. The hydrogen selectivity (vol%) order of the catalysts was achieved as Ni/CeO2–ZrO2>Ni/CeO2>Ni/Al2O3?Ni/CeO2-La2O3. The best catalytic activity of Ni/CeO2–ZrO2 catalyst (~82 vol % H2 at 800 °C) was ascribed to the smaller size of nickel crystals, finely dispersed Ni on the catalyst surface, and Ce1-xZrxO2-δ solid solution. The role of Ce1-xZrxO2-δ solid solution in Ni/CeO2–ZrO2 catalyst was observed as bi-functional; acceleration of water-gas-shift and oxidation of carbon reaction. The high resistance of Ni/CeO2–ZrO2 towards the coke formation showed its potential to establish a cost-effective commercial-scale biomass steam gasification process. This study is expected to provide a promising solution for the disposal of furniture wastes for production of clean energy (biohydrogen).  相似文献   
65.
Graphene nanoribbons (GNRs), obtained by different methods from carbon nanotubes (CNTs) or graphene, are attractive materials for polymer nanocomposites due to their considerably high interfacial area, as compared to CNTs. Consequently, a better adhesion with a polymer matrix is anticipated for GNRs. Also, surface modification of these nanofillers, such as nitrogen doping, is known to be an efficient method to improve their properties. In this work, fluoroelastomers (FKM) were used as the polymer matrix to host GNRs. Undoped and nitrogen doped GNRs were synthesized from the parent multiwall carbon nanotubes (MWCNTs). MWCNT/FKM and GNR/FKM nanocomposites were prepared via a solution mixing/melt mixing protocol.  相似文献   
66.
Regarding the application of renewable energies, their infiniteness and no pollutant production are two important reasons for the universal acceptance. In this issue, calculation of the initial capital cost and the payback time are of crucial importance. Considering the significance of air pollution problem in the metropolis of Tehran and its related challenges, the Iranian government has been required to apply renewable sources. This research deals with the investigation of environmental and economic aspects, implementation of Tehran City Council Legislation (TCCL) considering the provision of 10–20% of required energies from new energies in buildings which were given permission in 2014. A large amount of the energy is consumed for different purposes such as water heating and to provide this need, a solar water heater (SWH) can be applied. In fact, by implementation of TCCL, the annual profit obtained by exporting extra natural gas to the neighbouring countries is 210,939.25$, which is a result of preserving 421,878.5?m3 natural gas. Furthermore, production of pollutants such as CO2, SO2, and NOx reduced by 3045.40, 14.540, and 11.111 tons, respectively. Hence, reduction of environmental costs was calculated as 150,956.25$. Eventually, calculation of payback time for implementing SWH was obtained as 17 months.  相似文献   
67.
68.
Soy protein isolate (SPI) is used to modify energy storage performances of poly(ethylene oxide) (PEO). The pure PEO membranes are highly polar, but the extremely high energy loss led to very low discharged energy density for use. The addition of SPI in both high molecular weight PEO and low molecular weight PEO lead to greatly reduced polarization and stored energy density. However, it also largely reduces the current leakage and energy loss of the resulting membranes, leading to significantly enhanced discharged energy density. It is believed that the strong interactions between PEO and SPI are responsible for the energy storage properties aforementioned. Meanwhile, such interactions also result in a more brittle fracture behavior and reduced crystallinity of the PEO/SPI membranes. The enhanced discharged energy density and low energy loss suggest PEO/SPI membranes are promising dielectric materials for high efficiency energy storage applications where soluble and transient materials are desired. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45214.  相似文献   
69.
The well‐known Hilbert–Huang transform (HHT) consists of empirical mode decomposition to extract intrinsic mode functions (IMFs) and Hilbert spectral analysis to obtain time–frequency characteristics of IMFs through the Hilbert transform. There are two mathematical requirements that limit application of the Hilbert transform. Moreover, noise effects caused by the empirical mode decomposition procedure add a scatter to derivative‐based instantaneous frequency determined by the Hilbert transform. In this paper, a new enhanced HHT is proposed in which by avoiding mathematical limitations of the Hilbert spectral analysis, an additional parameter is employed to reduce the noise effects on the instantaneous frequencies of IMFs. To demonstrate the efficacy of the proposed method, two case studies associated with structural modal identification are selected. In the first case, through identification of a typical 3‐DOF structural model subjected to a random excitation, accuracy of the enhanced method is verified. In the second case, ambient response data recorded from a real 15‐story building are analyzed, and nine modal frequencies of the building are identified. The case studies indicate that the enhanced HHT provides more accurate and physically meaningful results than HHT and is capable to be an efficient tool in structural engineering applications. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
70.
Wood is one of the main materials used for making musical instruments due to its outstanding acoustical properties. Despite such unique properties, its inferior mechanical properties, moisture sensitivity, and time‐ and cost‐consuming procedure for making instruments in comparison with other materials (e.g., composites) are always considered as its disadvantages in making musical instruments. In this study, the acoustic parameters of three different polyester composites separately reinforced by carbon fiber, glass fiber, and hemp fiber are investigated and are also compared with those obtained for three different types of wood specimens called poplar, walnut, and beech wood, which have been extensively used in making Iranian traditional musical instruments. The acoustical properties such as acoustic coefficient, sound quality factor, and acoustic conversion factor were examined using some non‐destructive tests based on longitudinal and flexural free vibration and also forced vibration methods. Furthermore, the water absorption of these polymeric composites was compared with that of the wood samples. The results reveal that the glass fiber‐reinforced composites could be used as a suitable alternative for some types of wood in musical applications while the carbon fiber‐reinforced composites are high performance materials to be substituted with wood in making musical instruments showing exceptional acoustical properties. POLYM. COMPOS., 35:2103–2111, 2014. © 2014 Society of Plastics Engineers  相似文献   
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