针对双向多天线中继系统中信息易被窃听的问题,提出了两种安全波束成形方案:安全和速率最大化波束成形(secrecy sum rate maximization beamforming,SSRMB)与零空间波束成形(null space beamforming,NSB).SSRMB方案中,采用具有收敛特性...针对双向多天线中继系统中信息易被窃听的问题,提出了两种安全波束成形方案:安全和速率最大化波束成形(secrecy sum rate maximization beamforming,SSRMB)与零空间波束成形(null space beamforming,NSB).SSRMB方案中,采用具有收敛特性的连续凸估计策略,对非凸的安全和速率最大化问题进行求解,得到局部最优波束成形解.针对中继节点的天线个数大于窃听节点个数这一特殊场景,设计了低复杂度NSB方案,将中继转发的信息投影到等效窃听信道矩阵的零空间中,通过求解一个广义Rayleigh熵问题获得波束成形解.仿真结果表明,所提方案可以有效地提高系统的安全性能,SSRMB方案具有快速收敛特性.展开更多
In this paper,the minimal conjecture on the Veronese Generating submanifolds in S(1)5 is generalized to minmal submanifolds in Sm. Two classes of the Generating submanifolds of spherical minimal submanifolds in Minkow...In this paper,the minimal conjecture on the Veronese Generating submanifolds in S(1)5 is generalized to minmal submanifolds in Sm. Two classes of the Generating submanifolds of spherical minimal submanifolds in Minkowski space are respectively space-like Minimal submanifolds of Hyperbolic space and pseudo-Rie-mannian Minimal submanifolds of pseudo-Riemannian sphere and they are of 1-type submanifolds in Minkowski space is proved.展开更多
Residential area entrance space is an important part of residential areas, which influences space form and also influences the space composition of residents. Through different feature analyses of entrance space for d...Residential area entrance space is an important part of residential areas, which influences space form and also influences the space composition of residents. Through different feature analyses of entrance space for different influences of residents, it can achieve humanized space design and improve the overall level of residential area.展开更多
An effective design method of freeform micro lens array is presented for shaping varied laser beams into prescribed rectangular illumination. The variable separation mapping is applied to design concave freeform surfa...An effective design method of freeform micro lens array is presented for shaping varied laser beams into prescribed rectangular illumination. The variable separation mapping is applied to design concave freeform surfaces for constructing a freeform lens array. Several dedicated examples show that the designed freeform optical lens array can achieve a prescribed rectangular illumination pattern, especially without considering the initial states of incident laser beams. Both high collection efficiency and good spatial uniformity can be available simultaneously. Tolerance analysis is also performed to demonstrate that this optical device can well avoid fabricating difficulty in actual applications.展开更多
We conjecture a formula for the generating function of genus one Gromov-Witten invariants of the local Calabi-Yau manifolds which are the total spaces of splitting bundles over projective spaces. We prove this conject...We conjecture a formula for the generating function of genus one Gromov-Witten invariants of the local Calabi-Yau manifolds which are the total spaces of splitting bundles over projective spaces. We prove this conjecture in several special cases, and assuming the validity of our conjecture we check the integrality of genus one Bogomol'nyi-Prasad-Sommerfield(BPS) numbers of local Calabi-Yau 5-folds defined by Klemm and Pandharipande.展开更多
We establish an integration by parts formula on the path space with reference measure P, the law of the(reflecting) diffusion process on manifolds with possible boundary carrying geometric flow, which leads to the sta...We establish an integration by parts formula on the path space with reference measure P, the law of the(reflecting) diffusion process on manifolds with possible boundary carrying geometric flow, which leads to the standard log-Sobolev inequality for the associated Dirichlet form. To this end, we first modify Hsu's multiplicative functionals to define the damp gradient operator, which links to quasi-invariant flows; and then establish the derivative formula for the associated inhomogeneous diffusion semigroup.展开更多
文摘针对双向多天线中继系统中信息易被窃听的问题,提出了两种安全波束成形方案:安全和速率最大化波束成形(secrecy sum rate maximization beamforming,SSRMB)与零空间波束成形(null space beamforming,NSB).SSRMB方案中,采用具有收敛特性的连续凸估计策略,对非凸的安全和速率最大化问题进行求解,得到局部最优波束成形解.针对中继节点的天线个数大于窃听节点个数这一特殊场景,设计了低复杂度NSB方案,将中继转发的信息投影到等效窃听信道矩阵的零空间中,通过求解一个广义Rayleigh熵问题获得波束成形解.仿真结果表明,所提方案可以有效地提高系统的安全性能,SSRMB方案具有快速收敛特性.
文摘In this paper,the minimal conjecture on the Veronese Generating submanifolds in S(1)5 is generalized to minmal submanifolds in Sm. Two classes of the Generating submanifolds of spherical minimal submanifolds in Minkowski space are respectively space-like Minimal submanifolds of Hyperbolic space and pseudo-Rie-mannian Minimal submanifolds of pseudo-Riemannian sphere and they are of 1-type submanifolds in Minkowski space is proved.
文摘Residential area entrance space is an important part of residential areas, which influences space form and also influences the space composition of residents. Through different feature analyses of entrance space for different influences of residents, it can achieve humanized space design and improve the overall level of residential area.
基金supported by the National Natural Science Foundation of China(No.61405037)the Science and Technology Project of Fujian Province(No.2015H4014)
文摘An effective design method of freeform micro lens array is presented for shaping varied laser beams into prescribed rectangular illumination. The variable separation mapping is applied to design concave freeform surfaces for constructing a freeform lens array. Several dedicated examples show that the designed freeform optical lens array can achieve a prescribed rectangular illumination pattern, especially without considering the initial states of incident laser beams. Both high collection efficiency and good spatial uniformity can be available simultaneously. Tolerance analysis is also performed to demonstrate that this optical device can well avoid fabricating difficulty in actual applications.
文摘We conjecture a formula for the generating function of genus one Gromov-Witten invariants of the local Calabi-Yau manifolds which are the total spaces of splitting bundles over projective spaces. We prove this conjecture in several special cases, and assuming the validity of our conjecture we check the integrality of genus one Bogomol'nyi-Prasad-Sommerfield(BPS) numbers of local Calabi-Yau 5-folds defined by Klemm and Pandharipande.
基金supported by the National Natural Science Foundation of Zhejiang University of Technology(Grant No.2014X2011)the Starting-up Research Fund supplied by Zhejiang University of Technology(Grant No.1009007329)
文摘We establish an integration by parts formula on the path space with reference measure P, the law of the(reflecting) diffusion process on manifolds with possible boundary carrying geometric flow, which leads to the standard log-Sobolev inequality for the associated Dirichlet form. To this end, we first modify Hsu's multiplicative functionals to define the damp gradient operator, which links to quasi-invariant flows; and then establish the derivative formula for the associated inhomogeneous diffusion semigroup.
