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131.
132.
PLS-BP法近外光谱同时检测饲料组分的研究 总被引:2,自引:2,他引:0
建立了用偏最小二乘(partial least squares,PLS)与人工神经网络(artificial neural networks,ANN)联用对饲料样品同时测定水分、灰分、蛋白质、磷含量的预测校正模型.光谱数据用二阶微分及标准归一化处理(SNV),用PLS法将原始数据压缩提取前10个主成分与2个特征峰值作为12个输入向量,采用单隐层的反向传播人工神经网络(Back-Propagation Network,BP),确定中间层的神经元个数为23,初始训练迭代次数为1 000.PLS-BP模型对样品四个组分含量的预测决定系数(r2)分别为:0.995 0,0.998 0,0.999 0和0.967 0;样品平行扫描光谱预测值的标准偏差分别为:0.027 74,0.048 53,0.032 92和0.022 04. 相似文献
133.
模式识别技术用于果酸混合物分析 总被引:4,自引:2,他引:4
研究了偏最小二乘法和人工神经网络法用于水果的紫外可见多组分光度分析。当混合物中诸组分存在相互作用,光谱加和性受到 扰动时,PLS法和ANN法用于混和物的分析仍能得到较满意的结果。 相似文献
134.
光纤陀螺仪零漂是衡量光纤陀螺仪精度的重要指标。文中对某光纤陀螺仪的零偏数据进行分析和预处理,采用时间序列分析法建立了AR(2)模型,同时基于BP神经网络建立了预测模型。建模结果分析表明:AR建模方法简单易行,但适用性不如BP网络模型,BP网络模型建模精度高,但算法复杂且收敛速度慢,容易陷入局部极小,因此采用了改进训练方法,改善了BP网络性能。 相似文献
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136.
The current research focuses on the creation of a general technique that solves the key issue of any operational chemical plant, namely, how to strike a delicate balance between profit and environmental impact. As a case study, a commercial vinyl chloride monomer (VCM) production unit was used. This research produced a new modelling and optimization tool that commercial chemical plants can use to measure their environmental impact and strike a careful balance between profit and environmental damage. This paper demonstrates how to model commercial complex reactors using Aspen and ANN in an easy-to-use manner. The current study used a multi-objective hybrid ANN and genetic algorithm to find a delicate balance between profit and environmental damage. A case study of a commercial VCM manufacturing process demonstrates the efficacy of the proposed methodology. The suggested methodology creates optimal VCM reactor operating parameters, which can be used in commercial plants to increase profit. Furthermore, the suggested methodology creates a set of Pareto optimal solutions platform to acquire insight into the profit-environmental impact balance. These insights could be extremely beneficial to plant management in making educated decisions about plant operations. 相似文献
137.
A 21st century technique for food control: Electronic noses 总被引:20,自引:0,他引:20
This work examines the main features of modern electronic noses (e-noses) and their most important applications in food control in this new century. The three components of an electronic nose (sample handling system, detection system, and data processing system) are described. Special attention is devoted to the promising mass spectrometry based e-noses, due to their advantages over the more classical gas sensors. Applications described include process monitoring, shelf-life investigation, freshness evaluation, authenticity assessment, as well as other general aspects of the utilization of electronic noses in food control. Finally, some interesting remarks concerning the strengths and weaknesses of electronic noses in food control are also mentioned. 相似文献
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139.
人工神经网络分类鉴别苦丁茶红外光谱 总被引:7,自引:2,他引:7
为了分类鉴别苦丁茶,采用竞争神经网络(CNN)和反向传播人工神经网络(BP网络)两种模式的人工神经网络(ANN)分别分析了各种苦丁茶的红外谱图。作者采用25个样本作训练集,11个样本作检验集,用两种网络进行了训练。结果表明,CNN网络和BP网络均能够有效地实现苦丁茶产地的鉴别,但CNN网络能够进一步地区分苦丁茶的级别。实验表明,CNN速度快,预测结果准确,可望用竞争神经网络(CNN)和红外光谱法结合分类鉴别苦丁茶。 相似文献
140.
Cuneyt Sevim Asil Oztekin Ozkan Bali Serkan Gumus Erkam Guresen 《European Journal of Operational Research》2014
The purpose of this paper is to develop an early warning system to predict currency crises. In this study, a data set covering the period of January 1992–December 2011 of Turkish economy is used, and an early warning system is developed with artificial neural networks (ANN), decision trees, and logistic regression models. Financial Pressure Index (FPI) is an aggregated value, composed of the percentage changes in dollar exchange rate, gross foreign exchange reserves of the Central Bank, and overnight interest rate. In this study, FPI is the dependent variable, and thirty-two macroeconomic indicators are the independent variables. Three models, which are tested in Turkish crisis cases, have given clear signals that predicted the 1994 and 2001 crises 12 months earlier. Considering all three prediction model results, Turkey’s economy is not expected to have a currency crisis (ceteris paribus) until the end of 2012. This study presents uniqueness in that decision support model developed in this study uses basic macroeconomic indicators to predict crises up to a year before they actually happened with an accuracy rate of approximately 95%. It also ranks the leading factors of currency crisis with regard to their importance in predicting the crisis. 相似文献