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71.
Fluctuation of sales over time is one of the major problems faced by most of the industries. To alleviate this problem management
tries to base their plans on forecast of sales pattern, which are mostly adhoc and rarely provides solid foundation for the
plans. This study makes an attempt to solve this problem by taking a neural network approach, at the process of sales of footwear,
and arriving at an optimum neural network model. The algorithms used for developing such model through neural network are
both feedforward and recurrent Elman network. The data used in this work are the weekly sales of footwear and the information
about the seasonality of sales process. While solving the problem, the focus is on forecasting of weekly retail sales as per
the requirement of management. This work would reduce the uncertainty existing in the short-term/middle term planning of sales
and distribution logistics of footwear over different time horizons across the entire supply chain of footwear business. 相似文献
72.
分析了软测量技术在污水处理问题上的可行性,建立了径向基(RBF)神经网络软测量模型,对污水处理过程中的各种污染物质进行监控和预测。结果表明:应用软测量技术能较好的克服污水处理过程中由随机干扰、强非线性、大时变、严重滞后等因素带来的一系列问题,具有广阔的应用前景。 相似文献
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The objective of this study is to analyze health effects of arsenic pollution of drinking water using a geographical information system (GIS). The paper reports the regional impact of arsenic contamination in six administrative blocks of the central part of the Murshidabad district, West Bengal, India. In this area about 1,248,580 people are exposed to arsenic pollution out of whom 388,316 people are exposed to arsenic concentrations above 0.05?mg/L, the WHO maximum permissible level of arsenic in drinking water. The study estimates that 65% of the total area of the six blocks has arsenic concentrations below 0.05?mg/L, 26.12% of the area has arsenic concentrations above 0.05?mg/L, and for the rest of the area no arsenic distribution data available. The total number of expected death cases has been estimated considering the percent of risk involved in a concentration range and corresponding total population using such water for drinking purpose. The analysis forecasts that 11,890 people may risk death due to arsenic pollution in the whole life span. The maximum number of death cases is expected in Domkal and Beldanga 1 blocks and the minimum number of death cases is expected in Block Bhagabangola 2. This study also reports a comparison between the theoretical expectation of death cases and actual reported arsenicosis cases for the Domkal block. The areas of theoretical expectation and the areas of actually reported cases match fairly well except in a few cases. The present study helps planning and implementing of priority-based arsenic mitigation options. 相似文献
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本文针对一种含有自发电的特殊情况来进行负荷预测,对时间序列法在负荷预测的建模中应用,提出了一种ARMAX的模型,结合预测模型,将自发电作为一个大扰动来考虑。通过验证,得到了较好的结果。 相似文献
78.
本文根据神经网络的并行递推预估误差训练理论,建立了一种负荷预报的新算法——PRPE预报算法。该算法属利用多层前传网进行负荷预报的范畴,由于该算法有效的权重训练方式,使其收敛速度大大高于传统的BP算法。尽管该算法的训练过程比较复杂,但对于时段负荷预报这类单输出系统,总体训练时间较BP算法成倍减少,且预报精度较高。可用于在线短期负荷预报。 相似文献
79.
优选平滑系数的指数平滑法电量预测系统 总被引:6,自引:0,他引:6
本介绍了一个用指数平滑法开发的电量预测系统。系统中平滑系数的选择采用了新近提出的0.618优选法,系统具有预测精度高,运行速度快和使用方便的特点。 相似文献
80.
Flip Korn Alexandros Labrinidis Yannis Kotidis Christos Faloutsos 《The VLDB Journal The International Journal on Very Large Data Bases》2000,8(3-4):254-266
Association Rule Mining algorithms operate on a data matrix (e.g., customers products) to derive association rules [AIS93b, SA96]. We propose a new paradigm, namely, Ratio Rules, which are quantifiable in that we can measure the “goodness” of a set of discovered rules. We also propose the “guessing
error” as a measure of the “goodness”, that is, the root-mean-square error of the reconstructed values of the cells of the
given matrix, when we pretend that they are unknown. Another contribution is a novel method to guess missing/hidden values
from the Ratio Rules that our method derives. For example, if somebody bought $10 of milk and $3 of bread, our rules can “guess”
the amount spent on butter. Thus, unlike association rules, Ratio Rules can perform a variety of important tasks such as forecasting,
answering “what-if” scenarios, detecting outliers, and visualizing the data. Moreover, we show that we can compute Ratio Rules
in a single pass over the data set with small memory requirements (a few small matrices), in contrast to association rule mining methods
which require multiple passes and/or large memory. Experiments on several real data sets (e.g., basketball and baseball statistics,
biological data) demonstrate that the proposed method: (a) leads to rules that make sense; (b) can find large itemsets in
binary matrices, even in the presence of noise; and (c) consistently achieves a “guessing error” of up to 5 times less than
using straightforward column averages.
Received: March 15, 1999 / Accepted: November 1, 1999 相似文献