By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established...By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature.展开更多
We identify the functions whose polynomial multiples are weak＊ dense in Qp spaces and prove that if ｜f（z）｜ ≥ ｜g（z）｜ and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operato...We identify the functions whose polynomial multiples are weak＊ dense in Qp spaces and prove that if ｜f（z）｜ ≥ ｜g（z）｜ and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operator Mx on Qp spaces is cellular indecomposable.展开更多
By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equi...By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equilibrium existence theorems, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are established in noncompact product FC-spaces. These results improve and generalize some recent results in literature to product FC-spaces without any convexity structure.展开更多
The purpose of this article is to prescnt by using vector space methods. a formula as how to calculate the covariance of the outer product of two independent random vecters in inter product space and to makes a discus...The purpose of this article is to prescnt by using vector space methods. a formula as how to calculate the covariance of the outer product of two independent random vecters in inter product space and to makes a discussion on the covariance of the orthogonally invariant random vector and that of the weakly spherically distributed orter produt.展开更多
Let F be any commutative field. Let v be an integer≥1 and be a fixed 2v × 2v nonsingular alternate matrix over F. Define Sp(F)={T: 2v×2v matrix over F|TKT~T=K}. It is well-known that Sp(F) is a group with r...Let F be any commutative field. Let v be an integer≥1 and be a fixed 2v × 2v nonsingular alternate matrix over F. Define Sp(F)={T: 2v×2v matrix over F|TKT~T=K}. It is well-known that Sp(F) is a group with respect to the matrix multiplication and is called the symplectic group of degree 2v over F展开更多
In this paper we investigate generalized bi quasi variational inequalities in locally convex topological vector spaces. Motivated and inspired by the recent research work in this field,we establish several existence t...In this paper we investigate generalized bi quasi variational inequalities in locally convex topological vector spaces. Motivated and inspired by the recent research work in this field,we establish several existence theorems of solutions for generalized bi quasi variational inequalities,which are the extension and improvements of the earlier and recent results obtained previously by many authors including Sun and Ding [18],Chang and Zhang [23] and Zhang [24].展开更多
In this article, four new classes of systems of generalized vector quasi-equilibrium problems are introduced and studied in FC-spaces without convexity structure. The notions of Ci（x）-FC-partially diagonally quasico...In this article, four new classes of systems of generalized vector quasi-equilibrium problems are introduced and studied in FC-spaces without convexity structure. The notions of Ci（x）-FC-partially diagonally quasiconvex, Ci（x）-FC-quasiconvex, and Ci（x）-FC- quasiconvex-like for set-valued mappings are also introduced in FC-spaces. By applying these notions and a maximal element theorem, the nonemptyness and compactness of solution sets for four classes of systems of generalized vector quasi-equilibrium problems are proved in noncompact FC-spaces. As applications, some new existence theorems of solutions for mathematical programs with system of generalized vector quasi-equilibrium constraints are obtained in FC-spaces. These results improve and generalize some recent known results in literature.展开更多
The development of renewable energy power generation for carbon neutrality and energy transition has been increasing worldwide,leading to an increasing demand for high-power conversion.Compared with traditional interl...The development of renewable energy power generation for carbon neutrality and energy transition has been increasing worldwide,leading to an increasing demand for high-power conversion.Compared with traditional interleaved paralleling,the integrated paralleling of three-level inverters can further reduce the output harmonics.Moreover,a well-designed switching sequence ensures that the average circulating current is zero,which provides a superior and feasible solution to satisfy the demands of high-power operations.However,a large instantaneous loop current exists between shunt converters,which leads to disadvantages such as higher switching device stress and loss.In this study,by utilizing the state-distribution redundancy provided by the integrated modulation process,a new design for switch-ing sequences is suggested for the integrated modulation of shunt three-level converters.This design aims to reduce the circulating current while better preserving the same output current harmonics than traditional parallel methods.The proposal includes an in-depth analysis and explanation of the implementation process.Finally,the proposed method is validated through simulations and prototype experi-ments.The results indicate that compared with traditional methods,the adoption of the improved switching sequence presented in this study leads to an average reduction of 3.2%in the total harmonic distortion of the inverter’s output and an average decrease of 32%in the amplitude of the circulating current.Both the output harmonics and circulating currents are significantly suppressed across various modulation indices.展开更多
针对永磁同步电机下桥臂电流采样拓扑的无位置传感器控制系统,在低载波运行时受数字延时影响易导致位置估计精度低、电流纹波增大、稳定性差等问题,提出一种半周期计算、单采样双更新的空间矢量脉宽调制方法,有效减少系统数字延时。该...针对永磁同步电机下桥臂电流采样拓扑的无位置传感器控制系统,在低载波运行时受数字延时影响易导致位置估计精度低、电流纹波增大、稳定性差等问题,提出一种半周期计算、单采样双更新的空间矢量脉宽调制方法,有效减少系统数字延时。该方法在每个脉冲宽度调制(Pulse-Width Modulation,PWM)的载波过零处采样一次电流,并在采样结束后的半周期内完成目标电压矢量计算。考虑数字延时中电机转过的角度,将目标电压矢量在下一个PWM周期的前、后半周期输出,并分别补偿0.75 T s和1.25 T s等效延时(T s为PWM周期时间),以减小目标电压矢量与实际输出电压矢量之间的误差。将新方法应用于采用模型参考自适应速度观测器的永磁同步电机无位置传感器控制系统中,实验结果表明该方法位置估计精度高、电流纹波小,且可以稳定运行于额定负载、载波比为4.0的工况。展开更多
身份-矢量(identity-vector,i-vector)方法作为说话人确认领域中的主流方法之一,能够通过学习总变化空间来获取有效的低维说话人特征——i-vector特征.但是当开发集数据不充足时,会导致学习到的总变化空间模型误差较大;同时,还无法有效...身份-矢量(identity-vector,i-vector)方法作为说话人确认领域中的主流方法之一,能够通过学习总变化空间来获取有效的低维说话人特征——i-vector特征.但是当开发集数据不充足时,会导致学习到的总变化空间模型误差较大;同时,还无法有效确认此时的总变化空间是否因为预先设置的维度过高而学到了冗余信息.为此,本文将贝叶斯主成分分析(Bayesian Principal Component Analysis,BPCA)引入总变化空间的学习过程中,利用其来为总变化空间引入更多的先验信息,从而对开发集数据中包含的信息进行补充,并在先验信息的约束下削弱总变化空间中无效维的影响.实验结果表明,当开发集数据不充足时,相比于传统的总变化空间学习方法,BPCA方法能够有效提升说话人确认系统的识别性能.展开更多
In this paper, two problems about composition operator on Hardy space are considered. Firstly, a new estimation of the norm of a class of composition operators is given. Secondly, the cyclic behavior of the adjoint op...In this paper, two problems about composition operator on Hardy space are considered. Firstly, a new estimation of the norm of a class of composition operators is given. Secondly, the cyclic behavior of the adjoint operator of a composition operator is discussed.展开更多
文摘By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature.
基金supported by NNSF of China (10771130)Specialized Research Fund for the Doctoral Program of High Education (2007056004)+1 种基金NSF of GuangdongProvince (10151503101000025)NSF of Fujian Province (2009J01004)
文摘We identify the functions whose polynomial multiples are weak＊ dense in Qp spaces and prove that if ｜f（z）｜ ≥ ｜g（z）｜ and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operator Mx on Qp spaces is cellular indecomposable.
基金This project was supported by the NSF of Sichuan Education of China(2003A081)and SZD0406
文摘By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equilibrium existence theorems, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are established in noncompact product FC-spaces. These results improve and generalize some recent results in literature to product FC-spaces without any convexity structure.
文摘The purpose of this article is to prescnt by using vector space methods. a formula as how to calculate the covariance of the outer product of two independent random vecters in inter product space and to makes a discussion on the covariance of the orthogonally invariant random vector and that of the weakly spherically distributed orter produt.
文摘Let F be any commutative field. Let v be an integer≥1 and be a fixed 2v × 2v nonsingular alternate matrix over F. Define Sp(F)={T: 2v×2v matrix over F|TKT~T=K}. It is well-known that Sp(F) is a group with respect to the matrix multiplication and is called the symplectic group of degree 2v over F
文摘In this paper we investigate generalized bi quasi variational inequalities in locally convex topological vector spaces. Motivated and inspired by the recent research work in this field,we establish several existence theorems of solutions for generalized bi quasi variational inequalities,which are the extension and improvements of the earlier and recent results obtained previously by many authors including Sun and Ding [18],Chang and Zhang [23] and Zhang [24].
基金supported by the Scientific Research Fun of Sichuan Normal University (09ZDL04)the Sichuan Province Leading Academic Discipline Project (SZD0406)
文摘In this article, four new classes of systems of generalized vector quasi-equilibrium problems are introduced and studied in FC-spaces without convexity structure. The notions of Ci（x）-FC-partially diagonally quasiconvex, Ci（x）-FC-quasiconvex, and Ci（x）-FC- quasiconvex-like for set-valued mappings are also introduced in FC-spaces. By applying these notions and a maximal element theorem, the nonemptyness and compactness of solution sets for four classes of systems of generalized vector quasi-equilibrium problems are proved in noncompact FC-spaces. As applications, some new existence theorems of solutions for mathematical programs with system of generalized vector quasi-equilibrium constraints are obtained in FC-spaces. These results improve and generalize some recent known results in literature.
基金supported by the National Natural Science Foundation of China(Grant No.51977046)Wuxi University Research Start-up Fund for Introduced Talent(2022r021).
文摘The development of renewable energy power generation for carbon neutrality and energy transition has been increasing worldwide,leading to an increasing demand for high-power conversion.Compared with traditional interleaved paralleling,the integrated paralleling of three-level inverters can further reduce the output harmonics.Moreover,a well-designed switching sequence ensures that the average circulating current is zero,which provides a superior and feasible solution to satisfy the demands of high-power operations.However,a large instantaneous loop current exists between shunt converters,which leads to disadvantages such as higher switching device stress and loss.In this study,by utilizing the state-distribution redundancy provided by the integrated modulation process,a new design for switch-ing sequences is suggested for the integrated modulation of shunt three-level converters.This design aims to reduce the circulating current while better preserving the same output current harmonics than traditional parallel methods.The proposal includes an in-depth analysis and explanation of the implementation process.Finally,the proposed method is validated through simulations and prototype experi-ments.The results indicate that compared with traditional methods,the adoption of the improved switching sequence presented in this study leads to an average reduction of 3.2%in the total harmonic distortion of the inverter’s output and an average decrease of 32%in the amplitude of the circulating current.Both the output harmonics and circulating currents are significantly suppressed across various modulation indices.
文摘针对永磁同步电机下桥臂电流采样拓扑的无位置传感器控制系统,在低载波运行时受数字延时影响易导致位置估计精度低、电流纹波增大、稳定性差等问题,提出一种半周期计算、单采样双更新的空间矢量脉宽调制方法,有效减少系统数字延时。该方法在每个脉冲宽度调制(Pulse-Width Modulation,PWM)的载波过零处采样一次电流,并在采样结束后的半周期内完成目标电压矢量计算。考虑数字延时中电机转过的角度,将目标电压矢量在下一个PWM周期的前、后半周期输出,并分别补偿0.75 T s和1.25 T s等效延时(T s为PWM周期时间),以减小目标电压矢量与实际输出电压矢量之间的误差。将新方法应用于采用模型参考自适应速度观测器的永磁同步电机无位置传感器控制系统中,实验结果表明该方法位置估计精度高、电流纹波小,且可以稳定运行于额定负载、载波比为4.0的工况。
文摘身份-矢量(identity-vector,i-vector)方法作为说话人确认领域中的主流方法之一,能够通过学习总变化空间来获取有效的低维说话人特征——i-vector特征.但是当开发集数据不充足时,会导致学习到的总变化空间模型误差较大;同时,还无法有效确认此时的总变化空间是否因为预先设置的维度过高而学到了冗余信息.为此,本文将贝叶斯主成分分析(Bayesian Principal Component Analysis,BPCA)引入总变化空间的学习过程中,利用其来为总变化空间引入更多的先验信息,从而对开发集数据中包含的信息进行补充,并在先验信息的约束下削弱总变化空间中无效维的影响.实验结果表明,当开发集数据不充足时,相比于传统的总变化空间学习方法,BPCA方法能够有效提升说话人确认系统的识别性能.
基金This research is supported by the NNSF of China (10401027)
文摘In this paper, two problems about composition operator on Hardy space are considered. Firstly, a new estimation of the norm of a class of composition operators is given. Secondly, the cyclic behavior of the adjoint operator of a composition operator is discussed.
