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101.
本文针对 XS—ZY—125型塑料注射成型机,分析了现行通用的双联泵供油液压系统耗能大的原因。介绍了压力流量补偿负荷传感液压系统在注射机上应用的基本原理。通过应用上述两种液压系统分别驱动同一台注射机的生产运行对比试验和能耗测试分析,证明压力流量补偿负荷传感液压系统具有十分显著的节能效果。通过经济效益估算分析,指出进一步开发压力流量补偿负荷传感液压系统在注射机上的应用,不仅具有十分显著的经济效益,而且具有很大的社会效益。  相似文献   
102.
基于SVM的Web日志挖掘及潜在客户发现   总被引:4,自引:1,他引:3  
潜在的客户资源是商家未来的利润来源,发现了潜在的客户就可以制定相应的商业决策,并进行有针对性的客户关系管理。使用SVM方法对Web日志文件进行挖掘,以发现站点访问者中潜在客户的共同行为模式,并将其分为不同级别的目标客户群。同时,通过试验4种不同比例的训练样本,研究了非对称数据对分类结果的影响,以期获得较优的模型。  相似文献   
103.
介绍了印刷烫金机走纸控制器软硬件的设计方案,该控制器选用低栅压导通的功率场效应管作为步进电机驱动,控制CPU采用AVR单片机.控制器具有走纸长度设置、电机启停低速而运行高速、走纸完毕声光提示、设置参数掉电保护等功能.  相似文献   
104.
Summary: The next German census will be an Administrative Record Census. Data from several administrative registers about persons will be merged. Object identification has to be applied, since no unique identification number exists in the registers. We present a two–step procedure. We briefly discuss questions like correctness and completeness of the Administrative Record Census. Then we focus on the object identification problem, that can be perceived as a special classification problem. Pairs of records are to be classified as matched or not matched. To achieve computational efficiency a preselection technique of pairs is applied. Our approach is illustrated with a database containing a large set of consumer addresses.*This work was partially supported by the Berlin–Brandenburg Graduate School in Distributed Information Systems (DFG grant no. GRK 316). The authors thank Michael Fürnrohr for previewing the paper. We would like to thank also for the helpful comments of an anonymous reviewer.  相似文献   
105.
Many seemingly different problems in machine learning, artificial intelligence, and symbolic processing can be viewed as requiring the discovery of a computer program that produces some desired output for particular inputs. When viewed in this way, the process of solving these problems becomes equivalent to searching a space of possible computer programs for a highly fit individual computer program. The recently developed genetic programming paradigm described herein provides a way to search the space of possible computer programs for a highly fit individual computer program to solve (or approximately solve) a surprising variety of different problems from different fields. In genetic programming, populations of computer programs are genetically bred using the Darwinian principle of survival of the fittest and using a genetic crossover (sexual recombination) operator appropriate for genetically mating computer programs. Genetic programming is illustrated via an example of machine learning of the Boolean 11-multiplexer function and symbolic regression of the econometric exchange equation from noisy empirical data.Hierarchical automatic function definition enables genetic programming to define potentially useful functions automatically and dynamically during a run, much as a human programmer writing a complex computer program creates subroutines (procedures, functions) to perform groups of steps which must be performed with different instantiations of the dummy variables (formal parameters) in more than one place in the main program. Hierarchical automatic function definition is illustrated via the machine learning of the Boolean 11-parity function.  相似文献   
106.
针对肉食品专营店和餐饮店对冷冻肉的解冻需求,设计研制了一台新型高压静电解冻柜。该解冻柜采用了高压静电解冻技术。设计了基于可编程逻辑控制器( PLC)的控制系统,可自动调控解冻柜温湿度和电场强度。根据设计性能参数,计算了解冻过程所需加热、制冷负荷和加湿蒸汽量。经解冻实验表明,该解冻柜能缩短解冻时间,降低汁液流失率,抑制微生物的繁殖,且解冻后肉样外观新鲜,肉色泽鲜红,具有实际应用价值。  相似文献   
107.
阐述了在网络环境下网络本土化和机器翻译对翻译产业化的影响,分析了国内外翻译人才数量、行业需求变化,通过对传统翻译和网络翻译在运作模式上的比较,对翻译工作者如何应对互联网的挑战提出了要求.  相似文献   
108.
Abstract

Research involving administrative healthcare data to study patient outcomes requires the investigator to account for the patient’s disease burden in order to reduce the potential for biased results. Here we develop a comorbidity summary score based on variable importance measures derived from several statistical and machine learning methods and show it has superior predictive performance to the Elixhauser and Charlson indices when used to predict 1-year, 5-year, and 10-year mortality. We used two large Veterans Administration cohorts to develop and validate the summary score and compared predictive performance using the area under ROC curve (AUC) and the Brier score.  相似文献   
109.
The random pazking problem has been of interest to inoestigsccrs in seveal disciplines , Physical chemists have investigaced such models in two and three dimensions, Because of aralytical difficulties, one-dimensional analogacs have been explored and theseare referred to as the parking problem, A number of results areexplored and attempts are made to tie them together, Applicationsare also highlighted.  相似文献   
110.
ABSTRACT

The support vector machine (SVM), first developed by Vapnik and his group at AT&T Bell Laboratories, is being used as a new technique for regression and classification problems. In this paper we present an approach to estimating prediction intervals for SVM regression based on posterior predictive densities. Furthermore, the method is illustrated with a data example.  相似文献   
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