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财政科技投入与农业科研机构创新水平的长期均衡及短期动态关系研究——基于中国1998-2011年省级面板数据分析 被引量:5
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作者 吴雪莲 张俊飚 +1 位作者 何可 丰军辉 《华中农业大学学报(社会科学版)》 CSSCI 2015年第4期49-55,共7页
利用Topsis方法测度中国31个省份1998-2011年的农业科研机构创新水平,考察并预测了财政科技投入与农业科研机构创新的短期及长期动态关系。结果表明:财政科技投入对农业科研机构创新的长期弹性为0.67,短期弹性为0.55,当短期贡献偏离长... 利用Topsis方法测度中国31个省份1998-2011年的农业科研机构创新水平,考察并预测了财政科技投入与农业科研机构创新的短期及长期动态关系。结果表明:财政科技投入对农业科研机构创新的长期弹性为0.67,短期弹性为0.55,当短期贡献偏离长期均衡时,误差修正将以42.7%的力度使其回至长期均衡状态;财政科技投入与农业科研机构创新之间呈现出互为因果的关系,即增加财政科技投入能推动农业科研机构创新,同时创新水平越高的农业科研机构能获得越多的财政科技投入;从短期波动来看,农业科研机构创新对财政科技投入增长的正向冲击较小,贡献仅为2.7%;而财政科技投入对农业科研机构创新的提升则具有显著的正向作用,贡献达47.8%,且东、中、西区域变量之间的贡献度存在差异。由于农业科研机构创新对财政科技投入的贡献较小,创新水平高的省份和创新水平低的省份获得财政科技投入的差距不大,这显然不利于激励各省农业科研机构创新。实现"高创新吸引高财政科技投入"的科研体制,利于有效激发科研机构创新的积极性。 展开更多
关键词 财政科技投入 农业科研机构创新 面板VAR模型 短期动态
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基于卡尔曼滤波算法的间接胎压监测方法 被引量:2
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作者 谭德荣 王艳阳 张莉 《农机化研究》 北大核心 2007年第12期74-78,共5页
为了提高现有间接胎压监测系统的性能,把数字信号处理方法与间接胎压监测系统相结合,提出了车辆纵向和侧向两个动力学模型,利用卡尔曼滤波方法得出了轮胎相对半径与胎压之间的关系。在该模型下(除模糊状态以外),可以监测到任何一种胎压... 为了提高现有间接胎压监测系统的性能,把数字信号处理方法与间接胎压监测系统相结合,提出了车辆纵向和侧向两个动力学模型,利用卡尔曼滤波方法得出了轮胎相对半径与胎压之间的关系。在该模型下(除模糊状态以外),可以监测到任何一种胎压降低的情况,并且不受车速和转向的影响,改善了现有间接胎压监测系统的准确性和可靠性。该方法只需要ABS系统自带的轮速传感器和一个陀螺仪,硬件开支小,软件实现简单,有很强的工程实用价值。 展开更多
关键词 公路运输 轮胎胎压 理论研究 卡尔曼滤波 纵向动力学模型 侧向动力学模型
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基于无迹卡尔曼滤波软测量技术的汽车行驶状态估计 被引量:2
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作者 郝亮 郭立新 《科学技术与工程》 北大核心 2018年第27期79-84,共6页
为了有效解决电动汽车在行驶过程中的车速、质心侧偏角和横摆角速度等参数低成本测量的问题,采用无迹卡尔曼搭建了软测量算法;该算法充分考虑电动汽车动态行驶状况下非线性的影响因素,同时采用非线性的高速公路研究所动态轮胎模型对轮... 为了有效解决电动汽车在行驶过程中的车速、质心侧偏角和横摆角速度等参数低成本测量的问题,采用无迹卡尔曼搭建了软测量算法;该算法充分考虑电动汽车动态行驶状况下非线性的影响因素,同时采用非线性的高速公路研究所动态轮胎模型对轮胎侧向力进行精确估计。通过与Car Sim动力学仿真软件进行联合仿真,对比分析验证所建立的软测量算法能够准确、实时地估计出电动汽车的运动参数。 展开更多
关键词 电动汽车 低成本测量 无迹卡尔曼滤波 软测量算法 高速公路研究所动态轮胎模型 联合仿真
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单木生长模型边缘误差的传播规律 被引量:7
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作者 张守攻 《林业科学研究》 CSCD 北大核心 1994年第1期1-6,共6页
研究提出了生长模拟保护带应由边缘效应带和误差阻尼带两部分构成。边缘效应带的宽度等于林分平均优势木影响圈半径的2倍,阻尼带的宽度可根据模拟分期数和模拟精度估计。样地边缘误差呈衰减趋势由外向内逐级传播,各环带中树木竞争指... 研究提出了生长模拟保护带应由边缘效应带和误差阻尼带两部分构成。边缘效应带的宽度等于林分平均优势木影响圈半径的2倍,阻尼带的宽度可根据模拟分期数和模拟精度估计。样地边缘误差呈衰减趋势由外向内逐级传播,各环带中树木竞争指数的系统误差,可根据其与样地边缘的距离近似估计。利用生长模型一般形式推导出了竞争指数相对误差与生长模拟相对误差的转换函数,证明由边缘效应造成的不同位置树木生长模拟系统误差是可估的。该研究为单水生长模型生长模拟保护带宽度的确定提供了理论依据和实用的估计方法。 展开更多
关键词 单木生长模型 边缘误差 林分动态
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自适应软测量算法的汽车行驶状态估计 被引量:3
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作者 郝亮 郭立新 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2019年第1期70-76,共7页
为了实现车辆行驶状态低成本测量,设计了估计汽车行驶状态参数的传统无迹卡尔曼滤波器和能够有效解决噪声时变特性的次优Sage-Husa噪声估计器相结合算法,通过建立电动汽车3自由度的动力学模型和HSRI轮胎模型,且融合低成本测量的纵、横... 为了实现车辆行驶状态低成本测量,设计了估计汽车行驶状态参数的传统无迹卡尔曼滤波器和能够有效解决噪声时变特性的次优Sage-Husa噪声估计器相结合算法,通过建立电动汽车3自由度的动力学模型和HSRI轮胎模型,且融合低成本测量的纵、横向加速度和方向盘转向角传感器测量信息,从而可精确估计电动汽车行驶状态.在选定的典型工况下,通过与无迹卡尔曼软测量算法进行对比,硬件在环实验结果有效地验证了自适应无迹卡尔曼软测量算法具有很好的鲁棒性,且比无迹卡尔曼软测量算法更加能够有效地估计电动汽车的行驶状态. 展开更多
关键词 自适应无迹卡尔曼软测量算法 次优Sage-Husa噪声估计器 3自由度动力学模型 HSRI轮胎模型 硬件在环
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农业科研事业单位专业技术岗位聘用动态调整模式初探 被引量:5
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作者 张晔 龚殿 《农业科技管理》 2018年第5期77-80,共4页
在国家深化人才发展体制机制改革的背景下,构建人岗相适、才岗相适的专业技术岗位聘用管理机制是农业科研事业单位人力资源管理改革的重点。文章针对当前农业科研事业单位专业技术岗位聘用管理存在的人岗结构不匹配、岗位目标不明确、... 在国家深化人才发展体制机制改革的背景下,构建人岗相适、才岗相适的专业技术岗位聘用管理机制是农业科研事业单位人力资源管理改革的重点。文章针对当前农业科研事业单位专业技术岗位聘用管理存在的人岗结构不匹配、岗位目标不明确、评价体系不健全等问题,提出了通过实施专业技术岗位聘用动态调整模式,初步构建起"岗位能上能下,待遇能高能低,人员能进能出"的专业技术岗位聘用管理机制。 展开更多
关键词 农业科研事业单位 专业技术 岗位聘用 动态调整模式 初探
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Big Data Interprets US Opioid Crisis
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作者 Zidong Wang Poning Fan 《Proceedings of Business and Economic Studies》 2018年第3期23-29,共7页
Since 2010,there has been a new round of drug crises in the United States.The abuse of opioids has led to a sharp increase in the number of people involved in drug crimes in the United States.There is an urgent need t... Since 2010,there has been a new round of drug crises in the United States.The abuse of opioids has led to a sharp increase in the number of people involved in drug crimes in the United States.There is an urgent need to explore solutions to the drug crisis in the United States.In this paper,the model of in-depth analysis is established under the condition of obtaining the opioid data and the influence factor data of the large sample of five state[1].In the first part,we use the Highway Safety Research Institute model based on the differential equation model to predict the initial value,find the initial position of the drug transfer,and obtain the curve of the number of different groups over time by fitting the data,so that the curves can be predicted the changing trends of the groups in the future.It was found that in Kentucky State,the county’s most likely to start using opioids were Pike and Bale.In Ohio,the county’s most likely to start using opioids are Jackson and Scioto.In Pennsylvania State,Mercer and Lackawanna are the counties most likely to start using opioids.Martinsville and Galax are the counties where Virginia State is most likely to start using opioids.Logan and Mingo are the counties where West Virginia State is most likely to start using opioids.In the second part,the gray prediction model is used to further analyze the time series of each factor,the maximum likelihood estimation method is used to obtain the weight of each factor,and the weight coefficient matrix is used to simulate the multivariate regression equation,and the factors that have the greatest influence on opioid abuse are educational background and family composition.In the third part,the hypothesis test model of two groups(the data type is proportional)is used to verify the difference between the influence factors(including the predicted values)in the first two parts of the states,thus verifying the feasibility between them.At the same time,we put forward a few suggestions to combine the current situation in the United States with the CDC data.We believe that in order to address the opium crisis,the U.S.government needs to strengthen not only oversight of doctors'prescriptions,but also make joint efforts of all sectors of society to fundamentally reduce the barriers to the use of opioids. 展开更多
关键词 highway Safety research institute model synthetic drug data fitting GRAY prediction HYPOTHESIS test antidrug ADVICE
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Big Data Interprets US Opioid Crisis
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作者 Zidong Wang Poning Fan 《Proceedings of Business and Economic Studies》 2020年第6期68-74,共7页
Since 2010,there has been a new round of drug crises in the United States.The abuse of opioids has led to a sharp increase in the number of people involved in drug crimes in the United States.There is an urgent need t... Since 2010,there has been a new round of drug crises in the United States.The abuse of opioids has led to a sharp increase in the number of people involved in drug crimes in the United States.There is an urgent need to explore solutions to the drug crisis in the United States.In this paper,the model of in-depth analysis is established under the condition of obtaining the opioid data and the influence factor data of the large sample of five state[1].In the first part,we use the Highway Safety Research Institute model based on the differential equation model to predict the initial value,find the initial position of the drug transfer,and obtain the curve of the number of different groups over time by fitting the data,so that the curves can be predicted the changing trends of the groups in the future.It was found that in Kentucky State,the county's most likely to start using opioids were Pike and Bale.In Ohio,the county's most likely to start using opioids are Jackson and Scioto.In Pennsylvania State,Mercer and Lackawanna are the counties most likely to start using opioids.Martinsville and Galax are the counties where Virginia State is most likely to start using opioids.Logan and Mingo are the counties where West Virginia State is most likely to start using opioids.In the second part,the gray prediction model is used to further analyze the time series of each factor,the maximum likelihood estimation method is used to obtain the weight of each factor,and the weight coefficient matrix is used to simulate the multivariate regression equation,and the factors that have the greatest influence on opioid abuse are educational background and family composition.In the third part,the hypothesis test model of two groups(the data type is proportional)is used to verify the difference between the influence factors(including the predicted values)in the first two parts of the states,thus verifying the feasibility between them.At the same time,we put forward a few suggestions to combine the current situation in the United States with the CDC data.We believe that in order to address the opium crisis,the U.S.government needs to strengthen not only oversight of doctors'prescriptions,but also make joint efforts of all sectors of society to fundamentally reduce the barriers to the use of opioids. 展开更多
关键词 highway Safety research institute model synthetic drug data itting gray prediction hypothesis test antidrug advice
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