With the popularity of wireless networks and the prevalence of personal mobile computing devices, understanding the characteristic of wireless network users is of great significance to the network performance. In this...With the popularity of wireless networks and the prevalence of personal mobile computing devices, understanding the characteristic of wireless network users is of great significance to the network performance. In this study, system logs from two universities, Dartmouth College and Shanghai Jiao Tong University(SJTU), were mined and analyzed. Every user's log was represented by a user profile. A novel weighted social similarity was proposed to quantify the resemblance of users considering influence of location visits. Based on the similarity, an unsupervised learning method was applied to cluster users. Though environment parameters are different, two universities both form many social groups with Pareto distribution of similarity and exponential distribution of group sizes. These findings are very important to the research of wireless network and social network .展开更多
In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by ...In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by using self-similar tilings for the acceptable dilations on the Heisenberg group.展开更多
分析了空间低轨目标群的运行特点,提出了基于时序向量相似性的空间目标群匹配算法,提高了对低轨巨型星座的识别管理能力。首先,介绍了时序向量的降维方法,将目标群高维观测时序向量简化为空间构型序列;而后,提出了基于动态时间规整(Dyna...分析了空间低轨目标群的运行特点,提出了基于时序向量相似性的空间目标群匹配算法,提高了对低轨巨型星座的识别管理能力。首先,介绍了时序向量的降维方法,将目标群高维观测时序向量简化为空间构型序列;而后,提出了基于动态时间规整(Dynamic Time Warping,DTW)的目标群空间构型序列相似性判别算法;最后,利用星链卫星目标群仿真和实测数据对算法的匹配能力进行验证。结果表明该算法可实现空间目标群监测数据快速匹配,仿真数据匹配过程中,在群内目标缺失30%的条件下匹配成功率可达100%,在低缺失条件下(缺失率5%以内)群内目标识别成功率平均超过75%;实测数据匹配成功率可达100%。展开更多
A dynamic hesitant fuzzy linguistic group decisionmaking(DHFLGDM) problem is studied from the perspective of information reliability based on the theory of hesitant fuzzy linguistic term sets(HFLTSs). First, an approa...A dynamic hesitant fuzzy linguistic group decisionmaking(DHFLGDM) problem is studied from the perspective of information reliability based on the theory of hesitant fuzzy linguistic term sets(HFLTSs). First, an approach is applied to transform the dynamic HFLTSs(DHFLTSs) into a set of proportional linguistic terms to eliminate the time dimension. Second, expert reliability is measured by considering both group similarity and degree of certainty, and an optimization method is employed to quantify the linguistic terms by maximizing the group similarity. Third, through computing the attribute stability as well as its reliability, a combination rule which considers both reliability and weight is proposed to aggregate the information, and then the aggregated grade values and degree of stability are used to make a selection. Finally,the application and feasibility of the proposed method are verified through a case study and method comparison.展开更多
In the present paper, the investigation to the mixed convective boundary layer behavior over a horizontal plate is carried our. By applying transformation group theory, the analysis of the governing equations of conti...In the present paper, the investigation to the mixed convective boundary layer behavior over a horizontal plate is carried our. By applying transformation group theory, the analysis of the governing equations of continuity, momentum, energy and diffusion shows the existence of similarity solution for the problem provided that the temperature and concentration at the wall are proportional to x(4/(7-5n)) and that the moving speed of the plate is proportional to x((3-n)/(7-5n)), furthermore, a set of similarity equations is obtained. The similarity equations are solved numerically by a fourth-order Runge-Kutta scheme. The numerical results obtained for velocity, temperature and concentration distributions for Pr=0.72 and various values of the parameters Sc, K-1, K-2 and K-3 reveals the influence of these parameters on the flow, and hear and mass transfer behavior.展开更多
According to the aggregation method of experts' evaluation information in group decision-making,the existing methods of determining experts' weights based on cluster analysis take into account the expert's preferen...According to the aggregation method of experts' evaluation information in group decision-making,the existing methods of determining experts' weights based on cluster analysis take into account the expert's preferences and the consistency of expert's collating vectors,but they lack of the measure of information similarity.So it may occur that although the collating vector is similar to the group consensus,information uncertainty is great of a certain expert.However,it is clustered to a larger group and given a high weight.For this,a new aggregation method based on entropy and cluster analysis in group decision-making process is provided,in which the collating vectors are classified with information similarity coefficient,and the experts' weights are determined according to the result of classification,the entropy of collating vectors and the judgment matrix consistency.Finally,a numerical example shows that the method is feasible and effective.展开更多
A more general assumption than that in the classical one-dimensional large strain consolidation theory is adopted and the exact analytical solution of nonlinear finite strain self-weight consolidation based on this as...A more general assumption than that in the classical one-dimensional large strain consolidation theory is adopted and the exact analytical solution of nonlinear finite strain self-weight consolidation based on this assumption is obtained. By applying the same experimental data, the comparison of the solutions of linear and nonlinear finite strain theory, as well as the numerical calculating results based on finite element method is presented. The results of the comparison show that the analytical solution obtained here takes on better agreement with practical cases than that of linear one, and they also show that, compared with the solutions based on nonlinear theory, the settlement and the consolidation degree based on linear theory are smaller.展开更多
基金National Natural Science Foundation of China(No. 60970106)National High Technology Research and Development Program of China( No. 2011AA010500)
文摘With the popularity of wireless networks and the prevalence of personal mobile computing devices, understanding the characteristic of wireless network users is of great significance to the network performance. In this study, system logs from two universities, Dartmouth College and Shanghai Jiao Tong University(SJTU), were mined and analyzed. Every user's log was represented by a user profile. A novel weighted social similarity was proposed to quantify the resemblance of users considering influence of location visits. Based on the similarity, an unsupervised learning method was applied to cluster users. Though environment parameters are different, two universities both form many social groups with Pareto distribution of similarity and exponential distribution of group sizes. These findings are very important to the research of wireless network and social network .
基金Sponsored by the NSFC (10871003, 10701008, 10726064)the Specialized Research Fund for the Doctoral Program of Higher Education of China (2007001040)
文摘In this article, the properties of multiresolution analysis and self-similar tilings on the Heisenberg group are studied. Moreover, we establish a theory to construct an orthonormal Haar wavelet base in L^2(H^d) by using self-similar tilings for the acceptable dilations on the Heisenberg group.
文摘分析了空间低轨目标群的运行特点,提出了基于时序向量相似性的空间目标群匹配算法,提高了对低轨巨型星座的识别管理能力。首先,介绍了时序向量的降维方法,将目标群高维观测时序向量简化为空间构型序列;而后,提出了基于动态时间规整(Dynamic Time Warping,DTW)的目标群空间构型序列相似性判别算法;最后,利用星链卫星目标群仿真和实测数据对算法的匹配能力进行验证。结果表明该算法可实现空间目标群监测数据快速匹配,仿真数据匹配过程中,在群内目标缺失30%的条件下匹配成功率可达100%,在低缺失条件下(缺失率5%以内)群内目标识别成功率平均超过75%;实测数据匹配成功率可达100%。
基金supported by the National Natural Science Foundation of China(71171112 71502073+2 种基金 71601002)the Scientific Innovation Research of College Graduates in Jiangsu Province(KYZZ150094)the Anhui Provincial Natural Science Foundation(1708085MG168)
文摘A dynamic hesitant fuzzy linguistic group decisionmaking(DHFLGDM) problem is studied from the perspective of information reliability based on the theory of hesitant fuzzy linguistic term sets(HFLTSs). First, an approach is applied to transform the dynamic HFLTSs(DHFLTSs) into a set of proportional linguistic terms to eliminate the time dimension. Second, expert reliability is measured by considering both group similarity and degree of certainty, and an optimization method is employed to quantify the linguistic terms by maximizing the group similarity. Third, through computing the attribute stability as well as its reliability, a combination rule which considers both reliability and weight is proposed to aggregate the information, and then the aggregated grade values and degree of stability are used to make a selection. Finally,the application and feasibility of the proposed method are verified through a case study and method comparison.
文摘In the present paper, the investigation to the mixed convective boundary layer behavior over a horizontal plate is carried our. By applying transformation group theory, the analysis of the governing equations of continuity, momentum, energy and diffusion shows the existence of similarity solution for the problem provided that the temperature and concentration at the wall are proportional to x(4/(7-5n)) and that the moving speed of the plate is proportional to x((3-n)/(7-5n)), furthermore, a set of similarity equations is obtained. The similarity equations are solved numerically by a fourth-order Runge-Kutta scheme. The numerical results obtained for velocity, temperature and concentration distributions for Pr=0.72 and various values of the parameters Sc, K-1, K-2 and K-3 reveals the influence of these parameters on the flow, and hear and mass transfer behavior.
文摘According to the aggregation method of experts' evaluation information in group decision-making,the existing methods of determining experts' weights based on cluster analysis take into account the expert's preferences and the consistency of expert's collating vectors,but they lack of the measure of information similarity.So it may occur that although the collating vector is similar to the group consensus,information uncertainty is great of a certain expert.However,it is clustered to a larger group and given a high weight.For this,a new aggregation method based on entropy and cluster analysis in group decision-making process is provided,in which the collating vectors are classified with information similarity coefficient,and the experts' weights are determined according to the result of classification,the entropy of collating vectors and the judgment matrix consistency.Finally,a numerical example shows that the method is feasible and effective.
文摘A more general assumption than that in the classical one-dimensional large strain consolidation theory is adopted and the exact analytical solution of nonlinear finite strain self-weight consolidation based on this assumption is obtained. By applying the same experimental data, the comparison of the solutions of linear and nonlinear finite strain theory, as well as the numerical calculating results based on finite element method is presented. The results of the comparison show that the analytical solution obtained here takes on better agreement with practical cases than that of linear one, and they also show that, compared with the solutions based on nonlinear theory, the settlement and the consolidation degree based on linear theory are smaller.