In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an au...In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an auxiliary variable x. The estimator’s properties have been derived up to first order of Taylor’s series expansion. The efficiency conditions derived theoretically under which the proposed estimator performs better than existing estimators. Empirical studies have been done using real populations to demonstrate the performance of the developed estimator in comparison with the existing estimators. The proposed estimator as illustrated by the empirical studies performs better than the existing estimators under some specified conditions i.e. it has the smallest Mean Squared Error and the highest Percentage Relative Efficiency. The developed estimator therefore is suitable to be applied to situations in which the variable of interest has a positive correlation with the auxiliary variable.展开更多
In this paper, traffic systems with attachment and detachment have been studied by total-asymmetric simple exclusion processes （TASEPs）. Attachment and detachment in a one-dimensional system is a type of complex geo...In this paper, traffic systems with attachment and detachment have been studied by total-asymmetric simple exclusion processes （TASEPs）. Attachment and detachment in a one-dimensional system is a type of complex geometry that is relevant to biological transport with the random update rule. The analytical results are presented and have shown good agreement with the extensive Monte Carlo computer simulations.展开更多
This paper uses various mean-field approaches and the Monte Carlo simulation to calculate asymmetric simple exclusion processes with particles of arbitrary size in the successive defects system. In this system, the ho...This paper uses various mean-field approaches and the Monte Carlo simulation to calculate asymmetric simple exclusion processes with particles of arbitrary size in the successive defects system. In this system, the hopping probability p （p 〈 1） and the size d of particles are not constant, Through theoretical calculation and computer simulation, it obtains the exact theoretical results and finds that the theoretical results are in agreement with the computer simulation. These results are helpful in analysing the effect of traffic with different hopping probabilities p and sizes d of particle.展开更多
Srivastava and Jhajj [ 1 6] proposed a class of estimators for estimating population variance using multi auxiliary variables in simple random sampling and they utilized the means and variances of auxiliary variables....Srivastava and Jhajj [ 1 6] proposed a class of estimators for estimating population variance using multi auxiliary variables in simple random sampling and they utilized the means and variances of auxiliary variables. In this paper, we adapted this class and motivated by Searle [13], and we suggested more generalized class of estimators for estimating the population variance in simple random sampling. The expressions for the mean square error of proposed class have been derived in general form. Besides obtaining the minimized MSE of the proposed and adapted class, it is shown that the adapted classis the special case of the proposed class. Moreover, these theoretical findings are supported by an empirical study of original data.展开更多
The abyssal circulation in the Philippine Sea(PS)is investigated,with outputs from the Simple Ocean Data Assimilation version 2.2.4(SODA224).The deep-water currents in SODA224 are carefully evaluated,with sparse in si...The abyssal circulation in the Philippine Sea(PS)is investigated,with outputs from the Simple Ocean Data Assimilation version 2.2.4(SODA224).The deep-water currents in SODA224 are carefully evaluated,with sparse in situ observations in the North Pacific Ocean.In the upper deep layer(20003000 m)of the PS,a strong westward current,which originates from the Northeast Pacific Basin and enters the PS through the Yap-Mariana Junction,exists along 1114 N.This strong westward current bifurcates into two western boundary currents off the Philippines.The northward-flowing current flows out of the PS around 2021 N,whereas the southward-flowing current transports deep water from the northern hemisphere to the southern hemisphere.In the lower deep layer(30004500 m),the inflow water first flows northward to the east of the Western Mariana Basin and then turns westward at approximately 18 N.The inflow water mainly enters the Philippine Basin(PB),with a small part turning southward to constitute a weak cyclonic circulation.The water entering the PB mainly merges into a strong southward western boundary current in the south-ern PB.In the bottom layer(below 4500 m),both the northeast and northwest PB show single cyclonic gyres,whereas the south PB shows a single anticyclonic gyre.Moreover,comparisons with the observations indicate the possible existence of a cyclonic sense of circulation over the Philippine Trench.The current study provides the implications for future observations,which are needed to fur-ther investigate the temporospatial variations of the abyssal circulation in the PS on multiple scales.展开更多
针对传统船舶图像去噪算法难以对图像的边缘细节进行保留和分析,以及传统非局部均值去噪算法相似框选择困难等问题,提出基于简单线性迭代聚类(simple linear iterative clustering,SLIC)超像素分割的非局部均值船舶图像去噪算法。通过S...针对传统船舶图像去噪算法难以对图像的边缘细节进行保留和分析,以及传统非局部均值去噪算法相似框选择困难等问题,提出基于简单线性迭代聚类(simple linear iterative clustering,SLIC)超像素分割的非局部均值船舶图像去噪算法。通过SLIC算法对图像进行分割处理,界定图像的纹理区域和平滑区域;使用相似框搜索和匹配策略,提升匹配效果,并适当保留更多边缘细节,从而改善图像去噪的效果。实验结果表明,所提出的算法相较于其他传统的船舶图像去噪算法不仅能很好地保留船舶图像的边缘细节特点,而且能在一定程度上提高船舶图像的峰值信噪比,具有良好的去噪效果,可以用于智能航海领域船舶图像的去噪。展开更多
文摘In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an auxiliary variable x. The estimator’s properties have been derived up to first order of Taylor’s series expansion. The efficiency conditions derived theoretically under which the proposed estimator performs better than existing estimators. Empirical studies have been done using real populations to demonstrate the performance of the developed estimator in comparison with the existing estimators. The proposed estimator as illustrated by the empirical studies performs better than the existing estimators under some specified conditions i.e. it has the smallest Mean Squared Error and the highest Percentage Relative Efficiency. The developed estimator therefore is suitable to be applied to situations in which the variable of interest has a positive correlation with the auxiliary variable.
基金supported by the National Natural Science Foundation of China-Yunnan Union Foundation (Grant No.U0937604)
文摘In this paper, traffic systems with attachment and detachment have been studied by total-asymmetric simple exclusion processes （TASEPs）. Attachment and detachment in a one-dimensional system is a type of complex geometry that is relevant to biological transport with the random update rule. The analytical results are presented and have shown good agreement with the extensive Monte Carlo computer simulations.
基金Project supported by the National Key Fundamental Research and Development Project of China (Grant No 2005CB724206)
文摘This paper uses various mean-field approaches and the Monte Carlo simulation to calculate asymmetric simple exclusion processes with particles of arbitrary size in the successive defects system. In this system, the hopping probability p （p 〈 1） and the size d of particles are not constant, Through theoretical calculation and computer simulation, it obtains the exact theoretical results and finds that the theoretical results are in agreement with the computer simulation. These results are helpful in analysing the effect of traffic with different hopping probabilities p and sizes d of particle.
文摘Srivastava and Jhajj [ 1 6] proposed a class of estimators for estimating population variance using multi auxiliary variables in simple random sampling and they utilized the means and variances of auxiliary variables. In this paper, we adapted this class and motivated by Searle [13], and we suggested more generalized class of estimators for estimating the population variance in simple random sampling. The expressions for the mean square error of proposed class have been derived in general form. Besides obtaining the minimized MSE of the proposed and adapted class, it is shown that the adapted classis the special case of the proposed class. Moreover, these theoretical findings are supported by an empirical study of original data.
基金sponsored by the Aoshan Science and Technology Innovation Project(No.2016ASKJ12)the Open Fund of the Key Laboratory of Ocean Circula-tion and Waves,Chinese Academy of Sciences(No.KLO CW1503)the National Natural Science Foundation of China(Nos.41606107,41506008,41776012,41476002)
文摘The abyssal circulation in the Philippine Sea(PS)is investigated,with outputs from the Simple Ocean Data Assimilation version 2.2.4(SODA224).The deep-water currents in SODA224 are carefully evaluated,with sparse in situ observations in the North Pacific Ocean.In the upper deep layer(20003000 m)of the PS,a strong westward current,which originates from the Northeast Pacific Basin and enters the PS through the Yap-Mariana Junction,exists along 1114 N.This strong westward current bifurcates into two western boundary currents off the Philippines.The northward-flowing current flows out of the PS around 2021 N,whereas the southward-flowing current transports deep water from the northern hemisphere to the southern hemisphere.In the lower deep layer(30004500 m),the inflow water first flows northward to the east of the Western Mariana Basin and then turns westward at approximately 18 N.The inflow water mainly enters the Philippine Basin(PB),with a small part turning southward to constitute a weak cyclonic circulation.The water entering the PB mainly merges into a strong southward western boundary current in the south-ern PB.In the bottom layer(below 4500 m),both the northeast and northwest PB show single cyclonic gyres,whereas the south PB shows a single anticyclonic gyre.Moreover,comparisons with the observations indicate the possible existence of a cyclonic sense of circulation over the Philippine Trench.The current study provides the implications for future observations,which are needed to fur-ther investigate the temporospatial variations of the abyssal circulation in the PS on multiple scales.
文摘针对传统船舶图像去噪算法难以对图像的边缘细节进行保留和分析,以及传统非局部均值去噪算法相似框选择困难等问题,提出基于简单线性迭代聚类(simple linear iterative clustering,SLIC)超像素分割的非局部均值船舶图像去噪算法。通过SLIC算法对图像进行分割处理,界定图像的纹理区域和平滑区域;使用相似框搜索和匹配策略,提升匹配效果,并适当保留更多边缘细节,从而改善图像去噪的效果。实验结果表明,所提出的算法相较于其他传统的船舶图像去噪算法不仅能很好地保留船舶图像的边缘细节特点,而且能在一定程度上提高船舶图像的峰值信噪比,具有良好的去噪效果,可以用于智能航海领域船舶图像的去噪。
