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预负荷量海脉素对剖宫产患者硬膜外阻滞后低血压的预防作用
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作者 于灵芝 宋振瑞 +1 位作者 李刚 满敏 《山东医药》 CAS 北大核心 1998年第9期8-9,共2页
本研究前瞻性观察海脉素对剖宫产患者硬膜外阻滞后低血压的预防作用,现报告如下。1资料与方法本组剖宫产患者48例,年龄25~35岁,孕期38+4~42+2周。随机分为两组,各24例,术前诊断为妊高征者观察组8例,对照组6... 本研究前瞻性观察海脉素对剖宫产患者硬膜外阻滞后低血压的预防作用,现报告如下。1资料与方法本组剖宫产患者48例,年龄25~35岁,孕期38+4~42+2周。随机分为两组,各24例,术前诊断为妊高征者观察组8例,对照组6例。患者入室后吸氧,观察组经静脉留... 展开更多
关键词 剖腹产 硬膜外麻醉 低血压 海脉素 预负荷量
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Research on Natural Gas Short-Term Load Forecasting Based on Support Vector Regression 被引量:1
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作者 刘涵 刘丁 +1 位作者 郑岗 梁炎明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第5期732-736,共5页
Natural gas load forecasting is a key process to the efficient operation of pipeline network. An accurate forecast is required to guarantee a balanced network operation and ensure safe gas supply at a minimum cost.Mac... Natural gas load forecasting is a key process to the efficient operation of pipeline network. An accurate forecast is required to guarantee a balanced network operation and ensure safe gas supply at a minimum cost.Machine learning techniques have been increasingly applied to load forecasting. A novel regression technique based on the statistical learning theory, support vector machines (SVM), is investigated in this paper for natural gas shortterm load forecasting. SVM is based on the principle of structure risk minimization as opposed to the principle of empirical risk minimization in conventional regression techniques. Using a data set with 2 years load values we developed prediction model using SVM to obtain 31 days load predictions. The results on city natural gas short-term load forecasting show that SVM provides better prediction accuracy than neural network. The software package natural gas pipeline networks simulation and load forecasting (NGPNSLF) based on support vector regression prediction has been developed, which has also been applied in practice. 展开更多
关键词 structure risk minimization support vector machines support vectorregression load forecasting neural network
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Novel grey forecast model and its application 被引量:1
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作者 丁洪发 舒双焰 段献忠 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期315-320,共6页
The advancement of grey system theory provides an effective analytic tool for power system load fore-cast. All kinds of presently available grey forecast models can be well used to deal with the short-term load fore-c... The advancement of grey system theory provides an effective analytic tool for power system load fore-cast. All kinds of presently available grey forecast models can be well used to deal with the short-term load fore-cast. However, they make big errors for medium or long-term load forecasts, and the load that does not satisfythe approximate exponential increasing law in particular. A novel grey forecast model that is capable of distin-guishing the increasing law of load is adopted to forecast electric power consumption (EPC) of Shanghai. Theresults show that this model can be used to greatly improve the forecast precision of EPC for a secondary industryor the whole society. 展开更多
关键词 grey model load forecast electric power consumption
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Autonomous Kernel Based Models for Short-Term Load Forecasting
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作者 Vitor Hugo Ferreira Alexandre Pinto Alves da Silva 《Journal of Energy and Power Engineering》 2012年第12期1984-1993,共10页
The application of support vector machines to forecasting problems is becoming popular, lately. Several comparisons between neural networks trained with error backpropagation and support vector machines have shown adv... The application of support vector machines to forecasting problems is becoming popular, lately. Several comparisons between neural networks trained with error backpropagation and support vector machines have shown advantage for the latter in different domains of application. However, some difficulties still deteriorate the performance of the support vector machines. The main one is related to the setting of the hyperparameters involved in their training. Techniques based on meta-heuristics have been employed to determine appropriate values for those hyperparameters. However, because of the high noneonvexity of this estimation problem, which makes the search for a good solution very hard, an approach based on Bayesian inference, called relevance vector machine, has been proposed more recently. The present paper aims at investigating the suitability of this new approach to the short-term load forecasting problem. 展开更多
关键词 Load forecasting artificial neural networks input selection kernel based models support vector machine relevancevector machine.
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