考虑到在计算 H I值时 ,任何一种碱基在序列中出现的理论频数都应该大于 5 ,故而对原 H I公式进行了约化处理 ,并将约化后的 H I值与原 H I值作了对比 ,发现不同的约化方式所得到的 H I值在描述序列不均匀性时的效果是不同的 ,用编码区...考虑到在计算 H I值时 ,任何一种碱基在序列中出现的理论频数都应该大于 5 ,故而对原 H I公式进行了约化处理 ,并将约化后的 H I值与原 H I值作了对比 ,发现不同的约化方式所得到的 H I值在描述序列不均匀性时的效果是不同的 ,用编码区所偏好的约化语言进行约化后所得到的 H I值在应用于高 GC含量、中 GC含量以及总共的外显子和内含子的识别时 ,其效果要优于原 H展开更多
为减少电网提前或延迟退役电力变压器带来的巨大损失,提出了一种基于DAHP算法及非等间隔GM(1,1)模型的电力变压器技术寿命预测新方法。笔者首先从电力变压器特性出发,结合DAHP(改进的层次分析法)算法,构建电力变压器健康状况评估指标体...为减少电网提前或延迟退役电力变压器带来的巨大损失,提出了一种基于DAHP算法及非等间隔GM(1,1)模型的电力变压器技术寿命预测新方法。笔者首先从电力变压器特性出发,结合DAHP(改进的层次分析法)算法,构建电力变压器健康状况评估指标体系,并计算得到电力变压器的健康指数(health index)值。然后在电力变压器历年健康指数值基础上,结合灰色理论非等间隔GM(1,1)模型,建立了电力变压器技术寿命预测模型。最后,应用该模型分别对110、220、500 k V等级的在运电力变压器进行了技术寿命预测研究,验证了该方法的可行性,为电网退役电力变压器提供了参考依据。展开更多
Condition assessment is one of the most significant techniques of the equipment’s health management.Also,in PHM methodology cycle,which is a developed form of CBM,condition assessment is the most important step of th...Condition assessment is one of the most significant techniques of the equipment’s health management.Also,in PHM methodology cycle,which is a developed form of CBM,condition assessment is the most important step of this cycle.In this paper,the remaining useful life of the equipment is calculated using the combination of sensor information,determination of degradation state and forecasting the proposed health index.The combination of sensor information has been carried out using a new approach to determining the probabilities in the Dempster-Shafer combination rules and fuzzy c-means clustering method.Using the simulation and forecasting of extracted vibration-based health index by autoregressive Markov regime switching(ARMRS)method,final health state is determined and the remaining useful life(RUL)is estimated.In order to evaluate the model,sensor data provided by FEMTO-ST Institute have been used.展开更多
The Heilaigou basin,located in the Inner Mongolia of China,is predominantly influenced by the aeolian-fluvial actions,with complicated sediment transport conditions on the mainstream riverbed.In order to identify the ...The Heilaigou basin,located in the Inner Mongolia of China,is predominantly influenced by the aeolian-fluvial actions,with complicated sediment transport conditions on the mainstream riverbed.In order to identify the relationship between sedimentary particles and geomorphic processes,mechanisms for the formation of characteristics of grain size composition were investigated by analyzing grain size parameters and external dynamic geomorphologic features.Firstly,the grain size parameters of the riverbed,stream power,maximum grain size of the wind-blown particles and HI values of the mainstream channel were calculated and analyzed,and they were used to establish multiple regression functions of grain size parameters in order to determine the effects of wind and river actions on particles.The results show that sediments in different reaches are formed in different environments：the upper stream is controlled by fluvial and aeolian processes;the sorting properties of riverbed sediments in the middle stream are worse than those in the upper stream since they are affected mainly by fluvial processes as indicated by the larger stream power there;and the particles on the downstream riverbed are likely contributed by the Kubuqi Desert.The size of particles on the riverbed depends on the hydrodynamic conditions,but is not significantly associated with the evolution of landform.Sorting is significantly related to both the hydrodynamic conditions and wind actions.Riverbed deposits brought in by winds likely become finer from the lower to the upper reaches,which are not coarser than 0.88Φ.Generally speaking,the stream power has a major effect on sedimentation characteristics of the riverbed,followed by wind power.展开更多
文摘考虑到在计算 H I值时 ,任何一种碱基在序列中出现的理论频数都应该大于 5 ,故而对原 H I公式进行了约化处理 ,并将约化后的 H I值与原 H I值作了对比 ,发现不同的约化方式所得到的 H I值在描述序列不均匀性时的效果是不同的 ,用编码区所偏好的约化语言进行约化后所得到的 H I值在应用于高 GC含量、中 GC含量以及总共的外显子和内含子的识别时 ,其效果要优于原 H
文摘为减少电网提前或延迟退役电力变压器带来的巨大损失,提出了一种基于DAHP算法及非等间隔GM(1,1)模型的电力变压器技术寿命预测新方法。笔者首先从电力变压器特性出发,结合DAHP(改进的层次分析法)算法,构建电力变压器健康状况评估指标体系,并计算得到电力变压器的健康指数(health index)值。然后在电力变压器历年健康指数值基础上,结合灰色理论非等间隔GM(1,1)模型,建立了电力变压器技术寿命预测模型。最后,应用该模型分别对110、220、500 k V等级的在运电力变压器进行了技术寿命预测研究,验证了该方法的可行性,为电网退役电力变压器提供了参考依据。
文摘Condition assessment is one of the most significant techniques of the equipment’s health management.Also,in PHM methodology cycle,which is a developed form of CBM,condition assessment is the most important step of this cycle.In this paper,the remaining useful life of the equipment is calculated using the combination of sensor information,determination of degradation state and forecasting the proposed health index.The combination of sensor information has been carried out using a new approach to determining the probabilities in the Dempster-Shafer combination rules and fuzzy c-means clustering method.Using the simulation and forecasting of extracted vibration-based health index by autoregressive Markov regime switching(ARMRS)method,final health state is determined and the remaining useful life(RUL)is estimated.In order to evaluate the model,sensor data provided by FEMTO-ST Institute have been used.
基金National Natural Science Foundation of China(4137103641671004)
文摘The Heilaigou basin,located in the Inner Mongolia of China,is predominantly influenced by the aeolian-fluvial actions,with complicated sediment transport conditions on the mainstream riverbed.In order to identify the relationship between sedimentary particles and geomorphic processes,mechanisms for the formation of characteristics of grain size composition were investigated by analyzing grain size parameters and external dynamic geomorphologic features.Firstly,the grain size parameters of the riverbed,stream power,maximum grain size of the wind-blown particles and HI values of the mainstream channel were calculated and analyzed,and they were used to establish multiple regression functions of grain size parameters in order to determine the effects of wind and river actions on particles.The results show that sediments in different reaches are formed in different environments：the upper stream is controlled by fluvial and aeolian processes;the sorting properties of riverbed sediments in the middle stream are worse than those in the upper stream since they are affected mainly by fluvial processes as indicated by the larger stream power there;and the particles on the downstream riverbed are likely contributed by the Kubuqi Desert.The size of particles on the riverbed depends on the hydrodynamic conditions,but is not significantly associated with the evolution of landform.Sorting is significantly related to both the hydrodynamic conditions and wind actions.Riverbed deposits brought in by winds likely become finer from the lower to the upper reaches,which are not coarser than 0.88Φ.Generally speaking,the stream power has a major effect on sedimentation characteristics of the riverbed,followed by wind power.
