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1.
Economic contribution rate of education (ECRE) is the key factor of education economics. This article selected China, South Korea, United States and other countries for a total of 15 samples, and put the data of the same period under the framework of soft computing, to simulate the production chain of “education–potential human capital–actual human capital–economic growth”. The basic idea is: Firstly, 15 countries are softly categorized according to the level of science and technology (S&T) progress. Secondly, potential human capital and actual human capital establish the internal correlation (fuzzy mapping) in the same classification, and we conceptualize actual human capital as one production factor, joined with the other two production factors, fixed asset and land, to set up the fuzzy mapping to economic growth., and then calculate economic contribution rate of education of China and foreign by two fuzzy mapping of them. Thirdly, this paper analyzes the present state and differences in the development of education between China and foreign according to different ECRE, and offers proposals for promoting the education in China.  相似文献   
2.
Emission of chlorophyll fluorescence (ChlF) from photosystem II (PSII) is affected by both plant status and environmental conditions. In this work, a state space model structure for ChlF from PSII with temperature as a variable model parameter was developed to provide insights into the temperature effects on photosynthesis and greenhouse temperature control. Experiments were carried out at 20, 25, and 30°C to validate the capability and flexibility of the developed model structure. Simulations of ChlF emission were performed for different temperatures. The results demonstrated the effectiveness of the ChlF model structure and the findings are useful for the development of greenhouse temperature control strategies.Inspec keywords: fluorescence, state‐space methods, photosynthesis, temperature control, vegetationOther keywords: chlorophyll fluorescence, photosystem II, PSII, plant status, environmental conditions, state space model structure, variable model parameter, temperature effects, photosynthesis, ChlF emission, ChlF model structure, greenhouse temperature control strategies, temperature 20.0 degC, temperature 25.0 degC, temperature 30.0 degC  相似文献   
3.
Green houses play a vital role in modern agriculture. Artificial light illumination is very important in a green house. While light is necessary for plant growth, excessive light in a green house may not bring more profit and even damages plants. Developing a plant‐physiology‐based light control strategy in a green house is important, which implies that a state‐space model on photosynthetic activities is very useful because modern control theories and techniques are usually developed according to model structures in the state space. In this work, a simplified model structure on photosystem II activities was developed with seven state variables and chlorophyll fluorescence (ChlF) as the observable variable. Experiments on ChlF were performed. The Levenberg–Marquardt algorithm was used to estimate model parameters from experimental data. The model structure can fit experimental data with a small relative error (<2%). ChlF under different light intensities were simulated to show the effect of light intensity on ChlF emission. A simplified model structure with fewer state variables and model parameters will be more robust to perturbations and model parameter estimation. The model structure is thus expected useful in future green‐house light control strategy development.Inspec keywords: parameter estimation, fluorescence, lighting control, photosynthesis, agriculture, state‐space methods, greenhousesOther keywords: Levenberg–Marquardt algorithm, ChlF emission, state variables, green‐house light control strategy development, model parameter estimation, light intensity, model parameters, photosystem II activities, simplified model structure, state‐space model, plant‐physiology‐based light control strategy, plant growth, artificial light illumination, light‐adapted state, dark‐adapted state, photosystem II chlorophyll fluorescence transition  相似文献   
4.
Water and sediment samples were collected from 45 lakes along the middle-lower Yangtze River, China. Each lake was sampled seasonally, over a period of one year. Water quality variables and metals in sediments were measured. Lakes along the lowest part of the river, within the Yangtze River Delta, had highest nutrient concentrations and were eutrophic or hypereutrophic. Lakes displayed a gradient in many water chemistry variables, from the middle to the lower Yangtze River. Lakes of the Delta region had the highest conductivity, sulfate, turbidity, and Chl-a values, and the lowest dissolved oxygen concentrations. A number of lakes near urban areas in the study region also displayed similar conditions. Lakes polluted by heavy metals were found in the upper part of the lower Yangtze River and had high Cu, Cr, and Co concentrations in sediments. The mean Igeo (index of geoaccumulation) values for Cu, Cr, and Co classes ranged from 0 to 4, indicating moderate to heavy contamination, contributed mainly from untreated industrial waste water produced within the lake catchments. Lakes of the middle Yangtze River are generally in relatively better condition, except for those around urban zones, which experience higher nutrient and heavy metal loading. The spatial distribution of lake conditions in the area can be related to the policy of regional economic development. The Delta region in China is developed and includes such cities as Shanghai and Suzhou. Heavy industries have moved into the interior region of China too, and development of modern cities is now occurring under some level of environmental protection. Nevertheless, lakes in the central part are becoming seriously polluted with both heavy metals and nutrients because local authorities promote industrialization and urbanization to improve economic conditions, while often ignoring environmental protection. Pollution is increasingly occurring in upstream reaches, a tendency that will bring more environmental problems. Interior lakes of China require immediate attention to prevent further declines in water quality.  相似文献   
5.
This paper proposes a class of quasi-ARMAX models for non-linear systems. Similar to ordinary non-linear ARMAX models, the quasi-ARMAX models are flexible black-box models, but they have various linearity properties similar to those of linear ARMAX models. A modelling scheme is introduced to construct models consisting of two parts: a macro-part and a kernel-part. By using Taylor expansion and other mathematical transformation techniques, it is first constructed as a class of quasi-ARMAX interfaces (macro-parts) that have various linearity properties but contain some complicated coefficients. MIMO neurofuzzy models (kernel-parts) are then introduced to represent the complicated coefficients. It is shown that the proposed quasi-ARMAX models have both good approximation ability and some easy-to-use properties. The proposed models have been successfully applied to prediction, fault detection and adaptive control of non-linear systems.  相似文献   
6.
本文根据交通标志中汉字的高度及视认距离,推算出了满足停车距离需要的最低运动视力许用值。通过对1000多名驾驶员的实测统计分析及显著性检验,证实了驾驶员的运动视力在“事故”群中平均衰减45%,无事故群平均衰减39%。说明运动状态的视力衰减严重是导致交通事故的重要原因之一。  相似文献   
7.
阐述注流加铅法生产易切削合金结构钢的生产工艺和铅在钢中的形态及其分布特征。测定35CrMoPb钢的机械性能和切削性能,并与美国41∠40钢进行了对比。结果表明该含铅钢的化学成分均匀,机械性能与美国41∠40钢相当,符合35CrMo钢的标准要求,而切削性能大大优于35CrMo钢,主切削抗力降低12.5%—20%,刀具寿命提高一倍,工件光洁度约提高一个等级,断屑性能好,不出现不规则连续型屑,达到美国41∠40钢水平。  相似文献   
8.
采用上出料喷粉设备和石灰+ 电石+ 萤石的混合脱硫剂在12t 铁水包中进行喷粉脱硫工业性试验,结果表明:在保证喷粉量的情况下,可达到良好的脱硫效果;且设备运行稳定可靠,可实现粉—气比(kg/kg) 的亚浓相输送  相似文献   
9.
According to Hebb's cell assembly theory, the brain has the capability of function localization. On the other hand, it is suggested that in the brain there are three different learning paradigms: supervised, unsupervised, and reinforcement learning, which are related deeply to the three parts of brain: cerebellum, cerebral cortex, and basal ganglia, respectively. Inspired by the above knowledge of the brain in this paper we present a brainlike learning system consisting of three parts: supervised learning (SL) part, unsupervised learning (UL) part, and reinforcement learning (RL) part. The SL part is a main part learning input–output mapping; the UL part is a competitive network dividing input space into subspaces and realizes the capability of function localization by controlling firing strength of neurons in the SL part based on input patterns; the RL part is a reinforcement learning scheme, which optimizes system performance by adjusting the parameters in the UL part. Numerical simulations have been carried out and the simulation results confirm the effectiveness of the proposed brainlike learning system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 32–39, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20600  相似文献   
10.
利用Polyflow软件对填充了不同角度内模的衣架型机头流道进行了模拟。研究了不同内模夹角对流道压力分布、出口压力、出口速度以及流道内流体停留时间的影响。结果表明:不同角度内模填充机头流道后,流道压力分布、出口压力和出口速度无明显改变;流道内物料主要停留在歧管端部;通过改变内模夹角,可以改变物料最大停留时间及停留面积,内模夹角为40°时,流道内最大停留时间短,物料停留少。  相似文献   
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