S/VTOL(short/vertical take-off and landing)战斗机用推力矢量喷管是飞机实现短距起飞垂直降落,摆脱对跑道的依赖,减小航母的设计难度,及显著提高飞机机动性能的关键技术,已成为第4代战斗机和战斗机用航空发动机的设计标志。结合不同...S/VTOL(short/vertical take-off and landing)战斗机用推力矢量喷管是飞机实现短距起飞垂直降落,摆脱对跑道的依赖,减小航母的设计难度,及显著提高飞机机动性能的关键技术,已成为第4代战斗机和战斗机用航空发动机的设计标志。结合不同时期推力矢量喷管的特征和不同战斗机对推力矢量的技术要求,对短距起飞垂直降落战斗机用矢量喷管的结构特点、工作原理及发展状况进行了归纳及总结。详细提出了S/VTOL战斗机用推力矢量喷管的关键技术,并对开展S/VTOL战斗机用矢量喷管技术研究提出建议。展开更多
The aim of the present work is to study the complete, vertical and horizontal lifts using Tachibana and Visknnevskii operators along generalized almost r-contact structure in tangent bundle. We also prove certain theo...The aim of the present work is to study the complete, vertical and horizontal lifts using Tachibana and Visknnevskii operators along generalized almost r-contact structure in tangent bundle. We also prove certain theorems on Tachibana and Visknnevskii operators with Lie derivative and lifts.展开更多
Curvature properties are studied for the Sasaki metric on the （1, 1） tensor bundle of a Riemannian manifold. As an application, examples of almost para-Nordenian and para-Kahler-Nordenian B-metrics are constructed o...Curvature properties are studied for the Sasaki metric on the （1, 1） tensor bundle of a Riemannian manifold. As an application, examples of almost para-Nordenian and para-Kahler-Nordenian B-metrics are constructed on the （1, 1） tensor bundle by looking at the Sasaki metric. Also, with respect to the para-Nordenian B-structure, paraholomorphic conditions for the complete lifts of vector fields are analyzed.展开更多
文摘S/VTOL(short/vertical take-off and landing)战斗机用推力矢量喷管是飞机实现短距起飞垂直降落,摆脱对跑道的依赖,减小航母的设计难度,及显著提高飞机机动性能的关键技术,已成为第4代战斗机和战斗机用航空发动机的设计标志。结合不同时期推力矢量喷管的特征和不同战斗机对推力矢量的技术要求,对短距起飞垂直降落战斗机用矢量喷管的结构特点、工作原理及发展状况进行了归纳及总结。详细提出了S/VTOL战斗机用推力矢量喷管的关键技术,并对开展S/VTOL战斗机用矢量喷管技术研究提出建议。
基金supported by the National Key Research and Development Program of China(2017YFE0131500)the National Natural Science Foundation of China(62104204 and U21A20493)。
文摘The aim of the present work is to study the complete, vertical and horizontal lifts using Tachibana and Visknnevskii operators along generalized almost r-contact structure in tangent bundle. We also prove certain theorems on Tachibana and Visknnevskii operators with Lie derivative and lifts.
基金Project supported by the Scientific and Technological Research Council of Turkey(No.TBAG-108T590)
文摘Curvature properties are studied for the Sasaki metric on the （1, 1） tensor bundle of a Riemannian manifold. As an application, examples of almost para-Nordenian and para-Kahler-Nordenian B-metrics are constructed on the （1, 1） tensor bundle by looking at the Sasaki metric. Also, with respect to the para-Nordenian B-structure, paraholomorphic conditions for the complete lifts of vector fields are analyzed.
