The mapping of lexical form to meaning is essential to vocabulary acquisition in a second language. This paper reviews and analyzes the key models which help to reveal the process of adult learners' development of...The mapping of lexical form to meaning is essential to vocabulary acquisition in a second language. This paper reviews and analyzes the key models which help to reveal the process of adult learners' development of conceptual representation for words in a second language. It concludes that both learners' gradual development of L2 proficiency and the lexical and conceptual features of L2 words affect learners' achievement of direct concept mediation for L2 words.展开更多
In terms of 34-year monthly mean temperature series in 1946-1979,the multi-level maPPing model of neural netWork BP type was applied to calculate the system's fractual dimension Do=2'8,leading tO a three-level...In terms of 34-year monthly mean temperature series in 1946-1979,the multi-level maPPing model of neural netWork BP type was applied to calculate the system's fractual dimension Do=2'8,leading tO a three-level model of this type with ixj=3x2,k=l,and the 1980 monthly mean temperture predichon on a long-t6rm basis were prepared by steadily modifying the weighting coefficient,making for the correlation coefficient of 97% with the measurements.Furthermore,the weighhng parameter was modified for each month of 1980 by means of observations,therefore constrcuhng monthly mean temperature forecasts from January to December of the year,reaching the correlation of 99.9% with the measurements.Likewise,the resulting 1981 monthly predictions on a long-range basis with 1946-1980 corresponding records yielded the correlahon of 98% and the month-tO month forecasts of 99.4%.展开更多
A function which is reflexive is called by pre-mean, a more generalized definition of a mean. In this paper, we define a new pre-mean and study its properties, and then using the given invariant curve we consider the ...A function which is reflexive is called by pre-mean, a more generalized definition of a mean. In this paper, we define a new pre-mean and study its properties, and then using the given invariant curve we consider the problem of convergence of Gauss iteration of a kind of pre-mean type mappings generated by the exponential and logarithmic functions.展开更多
针对K-means聚类算法易受到初始聚类中心的影响且易陷入局部最优值的不足,提出一种基于改进蜣螂优化算法的K-means聚类算法。首先,引入分段线性混沌映射(Piecewise Linear Chaotic Map, PWLCM)改善种群多样性,提高算法的求解精度和收敛...针对K-means聚类算法易受到初始聚类中心的影响且易陷入局部最优值的不足,提出一种基于改进蜣螂优化算法的K-means聚类算法。首先,引入分段线性混沌映射(Piecewise Linear Chaotic Map, PWLCM)改善种群多样性,提高算法的求解精度和收敛速度;其次,受鱼鹰算法位置识别和捕鱼策略的启发,使用其全局勘探策略替换蜣螂优化算法滚球阶段策略,可以弥补算法在滚球阶段中只依赖最差值,无法与其它蜣螂进行交流的缺点,从而增强算法的全局探索能力;然后,加入动态选择的自适应t分布扰动,增加全局开发以及局部搜索能力,通过CEC2017测试函数验证改进蜣螂优化算法的有效性和优越;最后,将改进后的蜣螂优化算法与K-means聚类算法相结合,从UCI数据集中选取6个真实的数据集与其他学者提出的群智能算法优化的K-means进行对比仿真实验,结果表明本文改进后的聚类算法具有更好的求解精度和鲁棒性。展开更多
This note addresses monotonic growths and logarithmic convexities of the weighted （（1-t2）αdt2, -∞〈α〈∞, 0〈t〈1） integral means Aα,β（ f ,·） and Lα,β（ f ,·） of the mixed area （πr2）-βA（ f...This note addresses monotonic growths and logarithmic convexities of the weighted （（1-t2）αdt2, -∞〈α〈∞, 0〈t〈1） integral means Aα,β（ f ,·） and Lα,β（ f ,·） of the mixed area （πr2）-βA（ f ,r） and the mixed length （2πr）-βL（ f ,r） （0≤β≤1 and 0〈r〈1） of f （rD） and？f （rD） under a holomorphic map f from the unit disk D into the finite complex plane C.展开更多
文摘The mapping of lexical form to meaning is essential to vocabulary acquisition in a second language. This paper reviews and analyzes the key models which help to reveal the process of adult learners' development of conceptual representation for words in a second language. It concludes that both learners' gradual development of L2 proficiency and the lexical and conceptual features of L2 words affect learners' achievement of direct concept mediation for L2 words.
文摘In terms of 34-year monthly mean temperature series in 1946-1979,the multi-level maPPing model of neural netWork BP type was applied to calculate the system's fractual dimension Do=2'8,leading tO a three-level model of this type with ixj=3x2,k=l,and the 1980 monthly mean temperture predichon on a long-t6rm basis were prepared by steadily modifying the weighting coefficient,making for the correlation coefficient of 97% with the measurements.Furthermore,the weighhng parameter was modified for each month of 1980 by means of observations,therefore constrcuhng monthly mean temperature forecasts from January to December of the year,reaching the correlation of 99.9% with the measurements.Likewise,the resulting 1981 monthly predictions on a long-range basis with 1946-1980 corresponding records yielded the correlahon of 98% and the month-tO month forecasts of 99.4%.
文摘A function which is reflexive is called by pre-mean, a more generalized definition of a mean. In this paper, we define a new pre-mean and study its properties, and then using the given invariant curve we consider the problem of convergence of Gauss iteration of a kind of pre-mean type mappings generated by the exponential and logarithmic functions.
文摘针对K-means聚类算法易受到初始聚类中心的影响且易陷入局部最优值的不足,提出一种基于改进蜣螂优化算法的K-means聚类算法。首先,引入分段线性混沌映射(Piecewise Linear Chaotic Map, PWLCM)改善种群多样性,提高算法的求解精度和收敛速度;其次,受鱼鹰算法位置识别和捕鱼策略的启发,使用其全局勘探策略替换蜣螂优化算法滚球阶段策略,可以弥补算法在滚球阶段中只依赖最差值,无法与其它蜣螂进行交流的缺点,从而增强算法的全局探索能力;然后,加入动态选择的自适应t分布扰动,增加全局开发以及局部搜索能力,通过CEC2017测试函数验证改进蜣螂优化算法的有效性和优越;最后,将改进后的蜣螂优化算法与K-means聚类算法相结合,从UCI数据集中选取6个真实的数据集与其他学者提出的群智能算法优化的K-means进行对比仿真实验,结果表明本文改进后的聚类算法具有更好的求解精度和鲁棒性。
基金in part supported by NSERC of Canada and the Finnish Cultural Foundation
文摘This note addresses monotonic growths and logarithmic convexities of the weighted （（1-t2）αdt2, -∞〈α〈∞, 0〈t〈1） integral means Aα,β（ f ,·） and Lα,β（ f ,·） of the mixed area （πr2）-βA（ f ,r） and the mixed length （2πr）-βL（ f ,r） （0≤β≤1 and 0〈r〈1） of f （rD） and？f （rD） under a holomorphic map f from the unit disk D into the finite complex plane C.
