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42.
Depression is a mental psychological disorder that may cause a physical disorder or lead to death. It is highly impactful on the social-economical life of a person; therefore, its effective and timely detection is needful. Despite speech and gait, facial expressions have valuable clues to depression. This study proposes a depression detection system based on facial expression analysis. Facial features have been used for depression detection using Support Vector Machine (SVM) and Convolutional Neural Network (CNN). We extracted micro-expressions using Facial Action Coding System (FACS) as Action Units (AUs) correlated with the sad, disgust, and contempt features for depression detection. A CNN-based model is also proposed in this study to auto classify depressed subjects from images or videos in real-time. Experiments have been performed on the dataset obtained from Bahawal Victoria Hospital, Bahawalpur, Pakistan, as per the patient health questionnaire depression scale (PHQ-8); for inferring the mental condition of a patient. The experiments revealed 99.9% validation accuracy on the proposed CNN model, while extracted features obtained 100% accuracy on SVM. Moreover, the results proved the superiority of the reported approach over state-of-the-art methods.  相似文献   
43.
Clean Technologies and Environmental Policy - It is a global challenge to achieve sustainable economic growth by improving the environment. The present study discussed the role of the financial...  相似文献   
44.
In this study, we have demonstrated a simple and inexpensive process to fabricate electrowetting lens arrays with various curvatures (micron to submicron) on conductive and transparent polydimethylsiloxane (PDMS) molds without additional metal layers. The microlens arrays were fabricated using one-step dual diffuser lithography process, which utilizes a pair of diffusers to diffract the incident rays of UV light at wide angles before approaching the photoresist. Dimensional control and high fill factor was achieved by just varying the exposure energy and gap between the patterns in the photomask, respectively. The patterns were replicated in conductive and transparent Ag(n)-PDMS (5–20% Ag) with 15 μm thickness. High conductivity of 4.6 × 10?1 S/m and high transmission efficiency of 90% was demonstrated by Ag(n)-PDMS molds. Micro-nanolens arrays fabricated by the optimized corelation were utilized to demonstrate switchable wettability behavior of water droplet at different applied voltages. The electrowetting microlens array fabrication method introduced in this work has high potential to be incorporated in optoelectronics and biomedical devices.  相似文献   
45.
The results are presented of an experimental project into the residual strength characteristics of polymer adhesives used in anchoring steel reinforcement bars, following exposure to elevated temperatures. The adhesives tested were polyester resin and epoxy resin grouts. Two types of experiment were undertaken designed to investigate the residual bond strength as well as the compressive strength of specimens. For the bond strength determination, pull-out tests were carried out on 150 mm cubes. Compressive tests were undertaken on small cylindrical specimens. All specimens were exposed to different temperatures in pre-heated ovens and then allowed to cool down to normal laboratory temperatures prior to testing. In the bond tests, two types of failure were observed: splitting and slipping. Splitting of the cubes occurred in specimens exposed to temperatures below about 200° C, and the adhesive characteristics were in general enhanced. Slipping failures, by pulling through the adhesive, were obtained in specimens exposed to higher temperatures than about 200°C, and both the residual bond and compressive strengths were observed to diminish with increasing temperature. Additionally, the texture of the adhesive had changed, losing its cohesiveness. Based on this observation, an approach for assessing thein situ bond capacity of anchors is proposed.  相似文献   
46.
Samples of stabilized γ-BIMNVOX.x (Bi2V1?xMnxO5.5?x/2) oxide-ion conductor with a layered-perovskite type of structure were successfully synthesized under mild conditions by the microwave-assisted calcination of ethylene glycol–citrate xerogels using a modified domestic microwave oven. As-prepared samples were characterized in terms of phase stabilization and crystallization, crystal structure, crystallite size and electrical performance using thermal (DTA–TG) analysis, X-ray diffraction (XRD) technique, scanning emission electron microscopy (SEM) and AC impedance spectroscopy. Generally, the γ-BIMNVOX.x samples synthesized by the microwave-assisted calcination displayed shorter calcination time, smaller crystallite sizes and higher oxide-ion performance at lower temperatures than the samples prepared by the conventional heating process. However, these interesting features confer to the stabilized γ-BIMNVOX.x phases prepared by such novel technique a potential application in many electrochemical solid oxide devices.  相似文献   
47.
Acceptance sampling is used to decide either the whole lot will be accepted or rejected, based on inspection of randomly sampled items from the same lot. As an alternative to traditional sampling plans, it is possible to use Bayesian approaches using previous knowledge on process variation. This study presents a Bayesian two-sided group chain sampling plan (BTSGChSP) by using various combinations of design parameters. In BTSGChSP, inspection is based on preceding as well as succeeding lots. Poisson function is used to derive the probability of lot acceptance based on defective and non-defective products. Gamma distribution is considered as a suitable prior for Poisson distribution. Four quality regions are found, namely: (i) quality decision region (QDR), (ii) probabilistic quality region (PQR), (iii) limiting quality region (LQR) and (iv) indifference quality region (IQR). Producer’s risk and consumer’s risk are considered to estimate the quality regions, where acceptable quality level (AQL) is associated with producer’s risk and limiting quality level (LQL) is associated with consumer’s risk. Moreover, AQL and LQL are used in the selection of design parameters for BTSGChSP. The values based on all possible combinations of design parameters for BTSGChSP are presented and inflection points’ values are found. The finding exposes that BTSGChSP is a better substitute for the existing plan for industrial practitioners.  相似文献   
48.
The kinetics of the thermal decomposition of thiophene diluted in argon have been studied behind reflected shock waves in a single pulse shock tube over the temperature range 1598–2022 K and pressures between 2.5 and 3.44 bar. Product yields and composition were determined using capillary column gas chromatography with flame ionization detection and flame photometric sulphur selective detection. The principal hydrocarbon product at all temperatures was ethyne. Ethanethiol was found to be the major sulphur product together with H2S formed in significant concentrations at lower temperatures. Carbon disulphide was also formed at higher temperatures. Additional reaction products were CH4, C2H4, C3H4, C4H3, C4H6, C4H4, C6H6 and C4H2 with some traces were found of C5 and C6H5 species. It was concluded that pyrolysis of thiophene is initiated by C–S bond fission to form the C4H4S radical which reacts to give C4H3 + SH together with the reaction giving C3H4 + CS. The rate expression obtained for the pyrolysis reaction was k (C4H4S)=2.2×1011 exp (270 kJ mol−1) s−1. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
49.
The background from which psychology is emerging in Pakistan as a separate discipline, its major trends as a continuation of the traditions of Indian psychology are discussed, and lines of research and problems currently being faced by Pakistan psychologists are also indicated. Major sections are: Background of Pakistan Psychology, Current Trends (Psychology Laboratory in Pakistan, Professional Organization, Professional Journals, Recent Trends), and Future Prospects. "With the present rate of growth of psychology, coupled with an unusual enthusiasm among the younger generation of psychologists, there is great hope that Pakistan psychology will soon catch up with the current developments in other countries." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
Ultraviolet-C (UV-C) radiation significantly impacts living organisms. UV-C radiation can also be used as a pest management tool. Therefore, this study was designed to investigate the effect of UV-C radiation on the physiology and gene expression level of Plutella xylostella, a destructive vegetable pest. Results showed that, after exposure to UV-C radiation for 3, 6, 12, and 24 h, the activity of SOD (superoxide dismutase) and CAT (catalase) of P. xylostella increased, while the activity of PPO (polyphenol oxidase), POD (peroxidase), AChE (acetylcholinesterase), CarE (carboxylesterase), and ACP (acid phosphatase) decreased with increased exposure time. Correlation coefficient analyses indicated that the activity of CAT correlated positively, while PPO and CarE correlated negatively, with exposure time. Gene regulation analysis via qRT-PCR confirmed a significant increase in regulation in CAT, CarE, and PPO-related genes. We also investigated the effect of UV-C exposure on the virulence of Cordyceps fumosorosea against P. xylostella. Here, results indicated that when the fungal treatment was applied to larvae before UV-C radiation, the virulence of C. fumosorosea was significantly reduced. However, this decline in virulence of C. fumosorosea due to UV-C exposure remained only for one generation, and no effect was observed on secondary infection. On the other hand, when larvae were exposed to UV-C radiation before fungal application, the mortality rate significantly increased as the exposure time to UV-C radiation increased. From the current study, it could be concluded that UV-C exposure suppressed the immunity to P. xylostella, which later enhanced the virulence of entomopathogenic fungi. Moreover, the study also suggested that UV irradiation is an effective pest management tool that could be incorporated into pest management strategies, which could help reduce pesticide application, be economically beneficial for the farmer, and be environmentally safe.  相似文献   
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