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71.
Classical estimation of distribution algorithms (EDAs) generally use truncation selection to estimate the distribution of the good individuals while ignoring the bad ones. However, various researches in evolutionary algorithms (EAs) have reported that the bad individuals may affect and help solving the problem. This paper proposes a new method to use the bad individuals by studying the substructures rather than the entire individual structures to solve reinforcement learning (RL) problems, which generally factorize their entire solutions to the sequences of state–action pairs. This work was studied in a recent graph‐based EDA named probabilistic model building genetic network programming (PMBGNP), which could solve RL problems successfully, to propose an extended PMBGNP. The effectiveness of this work is verified in an RL problem, namely robot control. Compared to other related work, results show that the proposed method can significantly speed up the evolution efficiency. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
72.
The alkali metal thermal to electric converter (AMTEC) system which utilizes the sodium ion conductivity of a beta″‐alumina solid electrolyte (BASE) is expected to have high conversion efficiency above 30% including practical heat losses. However, the achieved experimental efficiencies have been around 15%. In this paper, current–voltage characteristics and heat and mass transfer processes on a single cell have been examined experimentally and thermal electrode conversion efficiency has been discussed. Measured electrode conversion efficiency without thermal losses showed that it was about 40% at a power density of 0.3 W/cm2. A theoretical analysis on the thermal losses has also been conducted and these losses are estimated to be 0.3 W/cm2 in a practical tube type cell, so that an actual cell system efficiency of 30% is expected. © 2001 Scripta Technica, Heat Trans Asian Res, 30(3): 234–244, 2001  相似文献   
73.
Patients with psoriasis are at a higher risk of developing nonalcoholic fatty liver disease. We previously identified an oxidized derivative of cholesterol, 7-ketocholesterol (7KC), in diet-induced steatohepatitic mice. Here, we investigated whether 7KC exacerbates psoriasis-like dermatitis by accelerating steatohepatitis in mice. A high-fat/high-cholesterol/high-sucrose/bile salt diet (nonalcoholic steatohepatitis (NASH) diet) with or without 0.0125% 7KC was fed to C57BL/6 mice (7KC or control group) for three weeks to induce steatohepatitis. A 5% imiquimod cream was then applied to the ears and dorsal skin for four days to induce psoriasis-like dermatitis. Hepatic lipid accumulation and inflammatory cell infiltration were exacerbated in the 7KC group compared with the control group after three weeks. Serum tumor necrosis factor-α (TNF-α) levels were also elevated in the 7KC group (108.5 ± 9.8 vs. 83.1 ± 13.1 pg/mL, p < 0.005). Imiquimod cream increased the psoriasis area severity index (PASI) score in mice in the 7KC group (9.14 ± 0.75 vs. 5.17 ± 1.17, p < 0.0001). Additionally, Tnfa, Il23a, Il17a, and Il22 mRNA levels in the dorsal lesion were significantly upregulated. Finally, Th17 cell differentiation and the TNF signaling pathway were enhanced in the dorsal lesions and liver of mice in the 7KC group. These data suggest that steatohepatitis and psoriasis are linked by a potent, diet-related factor.  相似文献   
74.
Field trials of the nonlinear color-appearance model were done by using chromatic object colors under different illuminance levels. Color-appearance match and brightness match were made for Munsell color pairs by using haploscopic matching. Each color pair was only different in Munsell Chroma. The color-appearance and the brightness match were realized by adjusting the illuminance of one of the two haploscopic fields. Observed illuminances were significantly different between the color-appearance and the brightness matches for the same color pairs. The model accurately predicted the illuminances of color-appearance matches by using the metrics of lightness and chroma Q, T, P of the model, and those of brightness matches by using the metric brightness of the chromatic color Bc. In addition, the estimated contribution of colorfulness to brightness of chromatic colors was generally consistent with that predicted by the formula of Ware and Cowan. To test metric brightness Bc further, an additional experiment on haploscopic matching was done using illuminants with different Ra values. In the experiment, the same samples were used in both fields. Again, matching illuminances in this case were well predicted by using the same contribution factor of colorfulness to brightness already estimated.  相似文献   
75.
The color-appearance models developed by R. W. G. Hunt (model H) and Y. Nayatoni and his collaborators (model N) are compared. The following color perceptions are analyzed: (1) colorfulness under illuminant C for NCS samples, (2) colorfulness change by changing illuminant C to illuminant A, (3) colorfulness change by changing adaptign illuminance, (4) Helson-Judd effect on achromatic colors under saturated chromatic illuminants, and (5) brightness and lightness. Special features of each model are made clear. In addition, a deatailed discussion is given on the mechanism introbucing the Helson-Judd effect and on the model formulations, especially in model H.  相似文献   
76.
We surveyed the literatures and discussed the legal issues whether we should administer blood for lifesaving to a patient who refuses it. The valid refusal of the transfusion requires the distinct intention of a competent patient. Minors below fifteen years of age are incompetent and their parents make a substituted judgement. Anyone must not give priority to the parents' belief and blood ought to be transfused if necessary for the children's benefits. We could evade liability for withholding blood only when we manage an operation arranged to succeed without blood transfusion, undergoing the sufficient treatments to avoid the risks, as well as on the basis of the valid refusal of a patient. The release deed and the intervention of hospital directors, ethics committees and courts are invalid for the immunity from liability. Anesthesiologists have to take the responsibility on themselves of administering blood or not. A statute law should be established to define what is a patient's valid intention and who is responsible.  相似文献   
77.
One of the main bottlenecks that limit the performance of reversible protonic ceramic electrochemical cells (R-PCECs) is the sluggish kinetics of the oxygen reduction and evolution reactions (ORR and OER). Here, the significantly enhanced ORR and OER kinetics and stability of a conventional La0.6Sr0.4Co0.2Fe0.8O3–δ (LSCF) air electrode by an efficient catalyst coating of barium cobaltite (BCO) is reported. The polarization resistance of a BCO-coated LSCF air electrode at 600 ° C is 0.16  Ω  cm2, about 30% of that of the bare LSCF air electrode under the same conditions. Further, an R-PCEC with the BCO-coated LSCF air electrode shows exceptional performance in both fuel cell (peak power density of 1.16 W cm−2 at 600 ° C) and electrolysis (current density of 1.80 A cm−2 at 600 ° C at 1.3 V) modes. The performance enhancement is attributed mainly to the facilitated rate of oxygen surface exchange.  相似文献   
78.
Polarized light scattering in bulk polymers is positively correlated with the intensity of dielectric fluctuation and the size of the heterogeneous structure, which is expressed by a correlation length. In this study, the influence of dielectric fluctuation was independently investigated for the first time on the basis of the difference in the light-scattering properties between two random copolymers – methyl methacrylate (MMA)/pentafluorophenyl methacrylate (PFPMA) and MMA/phenyl methacrylate (PMA). These copolymers have similar correlation lengths but show different intensities of dielectric fluctuation. When the difference of the mean-square average of the fluctuations of all dielectric constants between the copolymers was 105 × 10−10, the difference in isotropic light-scattering loss was 425 dB/km at 633 nm.  相似文献   
79.
Monitoring changes in a paddy-field area is important since rice is a staple food and paddy agriculture is a major cropping system in Asia. For monitoring changes in land surface, various applications using different satellites have been researched in the field of remote sensing. However, monitoring a paddy-field area with remote sensing is difficult owing to the temporal changes in the land surface, and the differences in the spatiotemporal characteristics in countries and regions. In this article, we used an artificial neural network to classify paddy-field areas using moderate resolution sensor data that includes spatiotemporal information. Our aim is to automatically generate a paddy-field classifier in order to create localized classifiers for each country and region.  相似文献   
80.
Genome size is considered one of the limiting factors for the replication of primitive life forms. However, the relationship between genome size and replication efficiency has not been tested experimentally. In this study, we examined the effect of genome size on genome replication by using an artificial cell model: a self‐replicating RNA genome encapsulated in a liposome. For the reduced genome size we used α‐complementation of the lacZ gene. We first characterized α‐complementation in the purified translation system and then applied α‐complementation to the genome replication system. The reduction in the genome size together with the addition of ω‐fragment increased the replication efficiency approximately eightfold. This result provides experimental evidence that genome size can be a limiting factor for primitive self‐replication systems; it also implies that this artificial cell model could be a useful experimental model to identify possible mechanisms of genome enlargement.  相似文献   
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