In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using concept...In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using conceptions of the relative error,the change tendency of the forecasted object,gray basic weight and adaptive control coefficient on the basis of the method of fuzzy variable weight.Based on Visual Basic 6.0 platform,a fuzzy adaptive variable weight combined forecasting and management system was developed.The application results reveal that the forecasting precisions from the new nonlinear combined forecasting model are higher than those of other single combined forecasting models and the combined forecasting and management system is very powerful tool for the required decision in complex industry system.展开更多
基金Project(08SK1002) supported by the Major Project of Science and Technology Department of Hunan Province,China
文摘In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using conceptions of the relative error,the change tendency of the forecasted object,gray basic weight and adaptive control coefficient on the basis of the method of fuzzy variable weight.Based on Visual Basic 6.0 platform,a fuzzy adaptive variable weight combined forecasting and management system was developed.The application results reveal that the forecasting precisions from the new nonlinear combined forecasting model are higher than those of other single combined forecasting models and the combined forecasting and management system is very powerful tool for the required decision in complex industry system.
文摘探究广西北部湾经济区(以下简称“研究区”)2001-2020年生态系统健康时空动态变化特征,可为研究区生态系统健康和社会经济可持续发展提供数据支持与理论参考。耦合“活力组织弹性”(Vigor Organization Resilience,VOR)模型、生态系统服务和权衡的综合评估(Integrated Valuation of Ecosystem Services and Trade offs,InVEST)模型构建生态系统健康多指标评价体系,并建立最小二乘法优化赋权模型对各评价指标进行优化赋权,对研究区生态系统健康状况进行评价与分析。结果表明:①研究区近20年来生态系统健康等级为三级的区域面积占研究区总面积的85%左右,且处于相对较为稳定的变化状态,研究区生态系统健康整体处于一般健康水平以上;②研究区生态系统健康状况总体上呈现北部、西部和南部地区优于中部和东部地区的空间分布差异;③研究区生态系统健康等级转移呈现以稳定型为主、退化型面积略大于改善型面积的空间变化特征,生态系统健康状况总体呈现轻微恶化趋势;④对研究区6个城市的生态系统健康从时间尺度和空间尺度对比分析发现,崇左、防城港、钦州3市生态系统健康状况变化较为明显,而南宁、玉林、北海3市相对较为平缓,但各市健康等级空间分布变化趋势较为吻合。本研究结果对推动广西北部湾经济区生态文明建设协调发展具有实际意义。
