An online data driven actor-critic-disturbance guidance law for missile-target interception with input constraints

In this article, we develop an online robust actor-critic-disturbance guidance law for a missile-target interception system with limited normal acceleration capability. Firstly, the missiletarget engagement is formulated as a zero-sum pursuit-evasion game problem. The key is to seek the saddle point solution of the Hamilton Jacobi Isaacs(HJI) equation, which is generally intractable due to the nonlinearity of the problem. Then, based on the universal approximation capability of Neural Networks(N...     

Time-optimal guidance for intercepting moving targets with impact-angle constraints

The minimum-time path for intercepting a moving target with a prescribed impact angle is studied in the paper. The candidate paths from Pontryagin’s maximum principle are synthesized,so that each candidate is related to a zero of a real-valued function. It is found that the real-valued functions or their first-order derivatives can be converted to polynomials of at most fourth degree.As a result, each candidate path can be computed within a constant time by embedding a standard polynomial solver...     

Adaptive event-triggered distributed optimal guidance design via adaptive dynamic programming

In this paper, the multi-missile cooperative guidance system is formulated as a general nonlinear multi-agent system. To save the limited communication resources, an adaptive eventtriggered optimal guidance law is proposed by designing a synchronization-error-driven triggering condition, which brings together the consensus control with Adaptive Dynamic Programming(ADP) technique. Then, the developed event-triggered distributed control law can be employed by finding an approximate solution of eve...     

Three-dimensional time-varying sliding mode guidance law against maneuvering targets with terminal angle constraint

This paper deals with the problem of intercepting maneuvering targets with terminal angle constraints for missiles subjected to three-dimensional non-decoupling engagement geometry.To achieve the finite-time interception and satisfactory overload characteristics, a time varying sliding mode control methodology is developed based on a time base generator function. The main feature of the proposed guidance law guarantees the Line-of-Sight(LOS) angles to converge to small neighborhoods of the desir...     

航空公司欧美国际航线运营持续时间生存分析

航空公司航线进入后的运营可持续性直接影响其盈利水平。基于生存分析方法探究影响航线运营持续时间的因素，从成本和供给特征、航线和机场特征、市场结构特征、航司合作类型和时间异质性5个方面选取关键因素，以自由化程度较高的欧美跨大西洋市场为实证对象，研究年份为2003—2021共19年，采用Kaplan-Meier方法进行单因素分析，并构建威布尔参数生存模型分析影响因素与航线运营持续时间的定量关系。结果表明：（1）航司在欧美航线的平均运营持续时间为5年，持续运营超过10年的航线占比为16%;(2)距离、航司投入总运力、航线结构、端点机场类型和竞争程度、航司类型及所属区域和联盟对航司航线运营持续时间具有显著影响；（3）联盟和代码共享独立变量和交互变量均对航线生存产生显著影响，星空和天合联盟成员的航线运营持续时间更长，联盟成员在代码共享合作时承担不同承运人角色对航线退出风险影响存在显著差异。     

A novel adaptive lateral reentry guidance algorithm with complex distributed no-fly zones constraints

Aimed at complex distributed no-fly zones avoidance problems, a novel adaptive lateral reentry guidance algorithm is proposed. Firstly, by introducing the improved attractive and repulsive potential fields, an improved artificial potential field method is developed. Combined with the proposed judgment criterion for whether a no-fly zone has been avoided, the proposed improved artificial potential field method effectively solves the reference heading angle determination problem under the constrai...