针对传统局部线性嵌入算法在挖掘局部流形结构时未充分考虑样本邻居分布信息,且在降维过程中默认样本具有相同的重要性导致提取鉴别特征不明显的问题,提出基于共享近邻的加权局部线性嵌入(weighted local linear embedding based on sha...针对传统局部线性嵌入算法在挖掘局部流形结构时未充分考虑样本邻居分布信息,且在降维过程中默认样本具有相同的重要性导致提取鉴别特征不明显的问题,提出基于共享近邻的加权局部线性嵌入(weighted local linear embedding based on shared neighbors,SN-WLLE)算法,并用于滚动轴承故障诊断.该算法首先使用余弦距离划分样本邻域;其次计算样本邻域对相似度用以评估样本共享近邻信息,并结合样本的6种邻居分布修正局部结构挖掘,提高多共享近邻的k近邻重构准确性;接着从多流形的角度评估样本点与近邻点间的稀疏分布一致性,以获得样本的重要性指标,并在低维空间保持该信息,进而提取准确的鉴别特征;最后结合KNN分类器构建出完备的轴承故障诊断模型.采用凯斯西储大学轴承数据集和实验室测试平台轴承数据集,从可视化评估、定量聚类评估、故障识别精度评估及鲁棒性评估等方面进行分析.结果表明:SN-WLLE算法的F值保持在108以上水准,平均故障识别精度最低可达0.9734,不仅具有较好的类内紧致性与类间可分性,还对近邻参数k具有低敏感性.展开更多
针对SAC(Soft Actor Critic)算法中所有样本都以等概率随机采样,造成训练速度慢,训练过程不稳定的缺点,提出了PER(Prioritized Experience Replay)-SAC算法。通过将优先级经验采样引入SAC算法,使网络优先训练值估计函数误差较大和策略...针对SAC(Soft Actor Critic)算法中所有样本都以等概率随机采样,造成训练速度慢,训练过程不稳定的缺点,提出了PER(Prioritized Experience Replay)-SAC算法。通过将优先级经验采样引入SAC算法,使网络优先训练值估计函数误差较大和策略表现不好的样本,从而提高了Agent训练过程的稳定性与收敛速度。实验结果表明,在多个环境及优化算法下,PER-SAC算法在训练速度及稳定性上相比于SAC算法均有明显提升。展开更多
CDM will reduce the global GHG emissions with lower costs while promoting sustainable development of the developing countries.However,the lack of distribution equilibrium has been a problem not solved for a long time....CDM will reduce the global GHG emissions with lower costs while promoting sustainable development of the developing countries.However,the lack of distribution equilibrium has been a problem not solved for a long time.In order to increase CDM distribution equilibrium in China,CDM support requirement extent of different areas is analyzed based on the study on the economic development and sustainable development capability.At the same time,registered and issued projects are analyzed to have an assessment on the CDM distribution equilibrium in China.Based on the study,it is concluded that there is a lack of CDM distribution equilibrium in China as most of CDM support has gone to the relatively more developed areas.Based on the reason analysis from the sector development,CDM market and information circulation aspects,suggestions are given to support CDM development in western areas by the"sector development guidance+CDM capability construction+market support"mode in this paper.展开更多
Global climate change has been identified as the first of the top ten environmental problems in the world. As climate change will have serious effects on the social and economic development and everyday, living of peo...Global climate change has been identified as the first of the top ten environmental problems in the world. As climate change will have serious effects on the social and economic development and everyday, living of people in the world, many of the countries and governments are taking untiring efforts to combat climate change. As one of the important mechanisms of reducing greenhouse gas (GHG) emissions in the Kyoto Protocol, Clean Development Mechanism (CDM) has not only provided chance for developed countries to fulfill greenhouse emission reduction obligations, but also provided an opportunity for developing countries to combat climate change under the sustainable development frame. The dual objectives of developed countries' GHG emissions' reduction obligation achievement and developing cotmtries'sustainable development will be achieved under the CDM. As a country with responsibility; China has been positively developing CDM projects and promoting energy saving and emissions reduction during the three yeors after the Kyoto Protocol came into force, and CDM projects development has always been in the front tank in the world. However; as the vast clime within China, notable differences occur in different regions. In order to promote the CDM development in China, it is necessa^T to have regional CDM capability construction in accordance with the practicality in different regions. Based on the Slat Analysis of developed CDM projects and current CDM development status in China, problems in the CDM development of China, including the inefficiency in small and medium-sized CDM Projects' development, over centralization of CDM development scope and especially the differentiated provincial CDM projects developing capability are pointed out in the paper: What's more, reasons for the problems are analyzed from fire leading.factors, including policy orient, information asymmetry and weak CDM capability, In order to promote CDM projects development in China, a new CDM capability, construction model is put forward in the paper.展开更多
文摘针对传统局部线性嵌入算法在挖掘局部流形结构时未充分考虑样本邻居分布信息,且在降维过程中默认样本具有相同的重要性导致提取鉴别特征不明显的问题,提出基于共享近邻的加权局部线性嵌入(weighted local linear embedding based on shared neighbors,SN-WLLE)算法,并用于滚动轴承故障诊断.该算法首先使用余弦距离划分样本邻域;其次计算样本邻域对相似度用以评估样本共享近邻信息,并结合样本的6种邻居分布修正局部结构挖掘,提高多共享近邻的k近邻重构准确性;接着从多流形的角度评估样本点与近邻点间的稀疏分布一致性,以获得样本的重要性指标,并在低维空间保持该信息,进而提取准确的鉴别特征;最后结合KNN分类器构建出完备的轴承故障诊断模型.采用凯斯西储大学轴承数据集和实验室测试平台轴承数据集,从可视化评估、定量聚类评估、故障识别精度评估及鲁棒性评估等方面进行分析.结果表明:SN-WLLE算法的F值保持在108以上水准,平均故障识别精度最低可达0.9734,不仅具有较好的类内紧致性与类间可分性,还对近邻参数k具有低敏感性.
文摘针对SAC(Soft Actor Critic)算法中所有样本都以等概率随机采样,造成训练速度慢,训练过程不稳定的缺点,提出了PER(Prioritized Experience Replay)-SAC算法。通过将优先级经验采样引入SAC算法,使网络优先训练值估计函数误差较大和策略表现不好的样本,从而提高了Agent训练过程的稳定性与收敛速度。实验结果表明,在多个环境及优化算法下,PER-SAC算法在训练速度及稳定性上相比于SAC算法均有明显提升。
基金supported by National Key Project of Scientific and Technical Supporting Programs Funded by Ministry of Science and Technology of China in the 11th Five-Year Plan (Grant No. 2007BAC03A04)
文摘CDM will reduce the global GHG emissions with lower costs while promoting sustainable development of the developing countries.However,the lack of distribution equilibrium has been a problem not solved for a long time.In order to increase CDM distribution equilibrium in China,CDM support requirement extent of different areas is analyzed based on the study on the economic development and sustainable development capability.At the same time,registered and issued projects are analyzed to have an assessment on the CDM distribution equilibrium in China.Based on the study,it is concluded that there is a lack of CDM distribution equilibrium in China as most of CDM support has gone to the relatively more developed areas.Based on the reason analysis from the sector development,CDM market and information circulation aspects,suggestions are given to support CDM development in western areas by the"sector development guidance+CDM capability construction+market support"mode in this paper.
基金supported by National Key Project of ScientificTechnical Supporting Programs Funded by Ministry of Science & Technology of China in the 11th Five-Year Plan (Grant No.2007BAC03A04)
文摘Global climate change has been identified as the first of the top ten environmental problems in the world. As climate change will have serious effects on the social and economic development and everyday, living of people in the world, many of the countries and governments are taking untiring efforts to combat climate change. As one of the important mechanisms of reducing greenhouse gas (GHG) emissions in the Kyoto Protocol, Clean Development Mechanism (CDM) has not only provided chance for developed countries to fulfill greenhouse emission reduction obligations, but also provided an opportunity for developing countries to combat climate change under the sustainable development frame. The dual objectives of developed countries' GHG emissions' reduction obligation achievement and developing cotmtries'sustainable development will be achieved under the CDM. As a country with responsibility; China has been positively developing CDM projects and promoting energy saving and emissions reduction during the three yeors after the Kyoto Protocol came into force, and CDM projects development has always been in the front tank in the world. However; as the vast clime within China, notable differences occur in different regions. In order to promote the CDM development in China, it is necessa^T to have regional CDM capability construction in accordance with the practicality in different regions. Based on the Slat Analysis of developed CDM projects and current CDM development status in China, problems in the CDM development of China, including the inefficiency in small and medium-sized CDM Projects' development, over centralization of CDM development scope and especially the differentiated provincial CDM projects developing capability are pointed out in the paper: What's more, reasons for the problems are analyzed from fire leading.factors, including policy orient, information asymmetry and weak CDM capability, In order to promote CDM projects development in China, a new CDM capability, construction model is put forward in the paper.