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121.
COVID-19 is a pandemic that has affected nearly every country in the world. At present, sustainable development in the area of public health is considered vital to securing a promising and prosperous future for humans. However, widespread diseases, such as COVID-19, create numerous challenges to this goal, and some of those challenges are not yet defined. In this study, a Shallow Single-Layer Perceptron Neural Network (SSLPNN) and Gaussian Process Regression (GPR) model were used for the classification and prediction of confirmed COVID-19 cases in five geographically distributed regions of Asia with diverse settings and environmental conditions: namely, China, South Korea, Japan, Saudi Arabia, and Pakistan. Significant environmental and non-environmental features were taken as the input dataset, and confirmed COVID-19 cases were taken as the output dataset. A correlation analysis was done to identify patterns in the cases related to fluctuations in the associated variables. The results of this study established that the population and air quality index of a region had a statistically significant influence on the cases. However, age and the human development index had a negative influence on the cases. The proposed SSLPNN-based classification model performed well when predicting the classes of confirmed cases. During training, the binary classification model was highly accurate, with a Root Mean Square Error (RMSE) of 0.91. Likewise, the results of the regression analysis using the GPR technique with Matern 5/2 were highly accurate (RMSE = 0.95239) when predicting the number of confirmed COVID-19 cases in an area. However, dynamic management has occupied a core place in studies on the sustainable development of public health but dynamic management depends on proactive strategies based on statistically verified approaches, like Artificial Intelligence (AI). In this study, an SSLPNN model has been trained to fit public health associated data into an appropriate class, allowing GPR to predict the number of confirmed COVID-19 cases in an area based on the given values of selected parameters. Therefore, this tool can help authorities in different ecological settings effectively manage COVID-19.  相似文献   
122.
The treatment of tannery wastewater by electrochemical oxidation, mediated by an electro-generated species was carried out under galvanostatic conditions in an electrochemical reactor equipped with anodes based on noble metals and metal oxides (Ti/Pt-Ir, Ti/PbO2, Ti/PdO-Co3O4 and Ti/RhO(x)-TiO2). The decrease in time of chemical oxygen demand, nitrogen (TKN and ammonia), Cr and sulphides was monitored. The study showed that the rate of pollutant removal was significantly influenced by the type of anode material and electrochemical parameters. Different mechanisms contributed to the removal of pollutants when the reactor operated under conditions close to the limiting current for chlorine evolution and under much higher current density, with the reactor performing better at a high current/voltage. The kinetic pseudo-first order model applied for the interpretation of the results showed that the Ti/Pt-Ir and Ti/PdO-Co3O4 anodes performed better than the other two electrodes under the majority of tested conditions, with the highest rate of removal obtained for ammonia (kinetic rate constant k=0.75 min(-1)). Electrochemical oxidation can be applied as a post-treatment after the conventional biological process in order to remove the residual ammonia with low energy consumption (0.4 kWh m(-3)).  相似文献   
123.
A bootstrap-based methodology is developed for parameter estimation and polyspectral density estimation in the case of the approximating model of the underlying stochastic process being non-minimum phase autoregressive-moving-average (ARMA) type, given a finite realisation of a single time series data. The method is based on a minimum phase/maximum phase decomposition of the system function together with a time reversal step for the parameter and polyspectral confidence interval estimation. Simulation examples are provided to illustrate the proposed method.  相似文献   
124.
The post enrolment course timetabling problem (PECTP) is one type of university course timetabling problems, in which a set of events has to be scheduled in time slots and located in suitable rooms according to the student enrolment data. The PECTP is an NP-hard combinatorial optimisation problem and hence is very difficult to solve to optimality. This paper proposes a hybrid approach to solve the PECTP in two phases. In the first phase, a guided search genetic algorithm is applied to solve the PECTP. This guided search genetic algorithm, integrates a guided search strategy and some local search techniques, where the guided search strategy uses a data structure that stores useful information extracted from previous good individuals to guide the generation of offspring into the population and the local search techniques are used to improve the quality of individuals. In the second phase, a tabu search heuristic is further used on the best solution obtained by the first phase to improve the optimality of the solution if possible. The proposed hybrid approach is tested on a set of benchmark PECTPs taken from the international timetabling competition in comparison with a set of state-of-the-art methods from the literature. The experimental results show that the proposed hybrid approach is able to produce promising results for the test PECTPs.  相似文献   
125.
In this paper, some new lattices of fuzzy substructures are constructed. For a given fuzzy set μ in a group G, a fuzzy subgroup S(μ) generated by μ is defined which helps to establish that the set Ls of all fuzzy subgroups with sup property constitutes a lattice. Consequently, many other sublattices of the lattice L of all fuzzy subgroups of G like , etc. are also obtained. The notion of infimum is used to construct a fuzzy subgroup i(μ) generated by a given fuzzy set μ, in contrast to the usual practice of using supremum. In the process a new fuzzy subgroup i(μ) is defined which we shall call a shadow fuzzy subgroup of μ. It is established that if μ has inf property, then i(μ) also has this property.  相似文献   
126.
Amphiphilic triblock copolymers composed of poly(p‐dioxanone) (PPDO) and poly(ethylene glycol) (PEG) were synthesized by ring opening polymerization of PDO initiated through dihydroxyl‐terminated PEG in the presence of stannous 2‐ethylhexanoate [Sn(oct)2] as a catalyst. Polymeric nanoparticles were prepared in an aqueous medium (triple distilled water and phosphate buffer pH 7.4) by cosolvent evaporation technique at room temperature (25°C). Stability of nanoparticles was significantly enough in triple distilled water when compared with the phosphate buffer. Core‐shell geometry of polymeric nanoparticles was characterized by 1H‐NMR spectroscopy and further confirmed by spectrophotometric analysis using pyrene as a probe. Variation in physicochemical characteristics of polymeric nanoparticles with the fraction of PPDO was investigated through the analysis of microscopic, spectroscopic, and light scattering techniques. Critical micelle concentration of polymer in triple distilled water decreased from 2.3 × 10?3 to 4.7 × 10?3. Atomic force microscopic observation revealed that polymeric nanoparticles were spherical and uniform with smooth textured of around 50–68 nm diameter. Dynamic light scattering and electrophoretic light scattering measurements showed a mono‐disperse size distribution of around 113–171 nm hydrodynamic diameters and negative zeta (ζ)‐potential (?4.00 to ?5.87 mV), respectively. The investigation showed a significant effect of polymeric composition on the physicochemical characteristic of polymeric nanoparticles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2695–2702, 2007  相似文献   
127.
This paper describes passenger comfort as an experience generated by the cabin interior features. The findings of previous studies are affirmed regarding a set of 22 context features. Passengers experience a certain level of comfort when these features impact their body and elicit subjective perceptions. New findings characterise these perceptions in the form of eight themes and outline their particular eliciting features. Comfort is depicted as a complex construct derived by passengers' perceptions beyond the psychological (i.e. peace of mind) and physical (i.e. physical well-being) aspects, and includes perceptual (e.g. proxemics) and semantic (e.g. association) aspects. The seat was shown to have a focal role in eliciting seven of those themes and impacting comfort through its diverse characteristics. In a subsequent study, a group of aircraft cabin interior designers highlighted the possibility of employing the eight themes and their eliciting features as a framework for design and evaluation of new aircraft interiors.  相似文献   
128.
The main objective of the present work was to fabricate poly(?‐caprolactone) grafted dextran (PGD) electrospun matrix (matrix) and to investigate the scaffold potential in tissue engineering application. In this work, at first we synthesized PGD polymer via ring opening polymerization (ROP), and with predetermined electrospinning conditions, nanofibrous matrix with high molecular weight PGD (PGD‐50, Mw = 45,500) has been successfully fabricated for the first time. Mouse osteoblast like cells, MC3T3 was used to test biocompatibility, assays of cell adhesion, survival, and effects on cell morphology of the matrix. The data demonstrate that PGD‐50 matrix represent a suitable substrate for supporting cell proliferation, process outgrowth and migration and as such would be a good material for artificial extra cellular matrix. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   
129.
Titanium nitride thin films were deposited on Si(1 0 0) substrates by using a low energy (2.3 KJ) Mather-type plasma focus device. The composition of the deposited films was characterized by X-ray diffraction (XRD). The crystallite size has strong dependence on the numbers of focus shots. The crystallinity of TiN thin films is found to increase with increasing the number of focus shots. The effect of different number of focus shots on micro structural changes of thin films was characterized by Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). SEM results showed net-like structure for film deposited for 15 numbers of shots, which are elongated grains of Si3N4 in amorphous form embedded into TiN crystals. The average surface roughness was calculated from AFM images of the thin films. These results indicated that the average surface roughness increased for films deposited with increased number of focus shots. The least crystallite size and roughness are observed for film deposited with 25 focus shots.  相似文献   
130.
The superposition of ultraviolet radiation induced (photodamage) aging process is photoaging. Antioxidant peptides derived from Pinctada fucata protein as raw materials were smeared the back of light-aging. The effect of antioxidant peptides on wrinkle generating, skin restoration capacity after pulled up and measure the active of the superoxide dismutase (SOD), catalase (CAT), hydroxyproline, and glutathione peroxidase (GSH-Px) and lipid peroxidation by kit and histological examination of UVB-irradiated skin that the mitotic index of basal cells, the thickness ratio of the epidermis and dermis, fibroblast count, density of collagen fibers and volume density of dermal microvasculature were studied. The result showed that antioxidant peptides had slowed down the progress of wrinkles formation and skin elasticity deceasing induced by acute irradiation of UVB. It also significantly controlled the speed of lipid peroxidation and the reduction of the activity of SOD, GSH-Px, hydroxyprodline and CAT. Histopathological studies showed that the derived antioxidant peptides could reduce the thickness ratio of the dermis and epidermis and increase the mitotic index of basal cells, fibroblast count, density of collagen fibers and volume density of dermal microvascular, these outcomes confirmed the protective role of antioxidant peptides in the process of photoaging.  相似文献   
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