This thesis research on a kind of anti - defence technology named wary trajectory technology , which inherits from mobile changeable trajectory technology 本文研究一种由机动变轨技术演化而来的跳跃式弹道技术。
Spanish companies have developed a gauge - changing mechanism that realigns wheels on tracks of different widths ( for instance , at the border between countries ) 西班牙公司开发了一种变轨技术，可以应用到不同的轨距上，例如在国境出。
You could throw a switch diverting it to a siding , but an equally unsuspecting man is standing there and the train will kill him instead 你可以扳动一根变轨开关，将电车转移到一侧，在那里站着的是一位同样不知情的人，而列车则会将他压死。
Adjoint function algorithms and direct collocation and nonlinear programming methods are applied to resolve the non - coplanar optimal orbit transfers problem 分别利用了共轭函数法与直接配置和非线性规划方法对异面最优变轨问题进行了求解。
Shenzhou 6 underwent its first orbit maintenance operation to restore the vessel to its original trajectory by firing its engine for 6 . 5 seconds in its 30th revolution around the earth 神舟六号飞船在第30圈飞行中，飞船发动机点火6 . 5秒，进行变轨后的首次轨道维持，以保持太空船在预定轨道。
The analysis shows that the wait time and maneuver impulse have close relationship to target ' s orbital period . if the time waited properly , the maneuver impulse can be greatly reduced 然后,对机动前待机时间进行了探讨,研究表明机动前待机时间与目标器轨道周期密切相关,且机动前待机时间的存在大大降低了交会机动变轨能耗。
A simplification in the foundation of actual dynamics model and the differential equation of aircraft movement are put forward , we have non - dimensionalized the equations . an optimal guidance model for orbit transfers is accomplished by the optimal control theory 本文围绕平面情况下飞行器最佳变轨路径这一主题，在实际力学模型基础上进行简化，建立飞行器运动微分方程，并加以无量纲化处理。
The problem is described for the determination of optimal spacecraft trajectories in an inverse - square field using low - thrust in this paper . the differential equation of aircraft is obtained by simplification of atmospheric model , then we do non - dimensionalized the equations 本文主要讨论了在反平方场中采用小推力下飞行器的最优变轨问题，通过对大气模型的简化，建立了飞行器的运动微分方程，然后加以无量纲化。
Green " s theorem is employed to find the quantity relationship among the constraints of heating rate , dynamic pressure and lift in reentry flight . the paper deduced the approximate solution of the optimal aeroassisted coplanar trajectories under the three typical constraints . the performance index to be minimized are either heat input , the total dynamic pressure , time during the atmospheric flight , the time integral of the square of the path inclination ; or maximize the time of flight during the atmospheric portion of the trajetory . an important conclusion is firstly obtained : under the three constraints above , the optimal aeroassisted coplanar transfers with the first forth kinds payoffs have the same optimal control laws 采用格林函数法，给出了同一平面气动力辅助变轨飞行的3种过程约束(气动加热率、动压、升力约束)条件之间关系的近似定量描述形成的飞行包络线.由此求解了航天器同时受3种约束条件时，各种性能指标下的同一平面气动力辅助变轨轨迹的近似解及相应的最优控制规律.文中对近似解与控制规律的内部结构作了细致的分析，得到了一些有益的结论
And with the results of calculation obtained by the first - order gradient algorithms which is initial value of the neighboring extremal algorithms we can transform the problem into a face to point one , then a good result is attained by the neighboring extremal algorithms . in the end , the course of orbit transfers is depicted 利用梯度法对两点边值问题进行计算，将面对面的问题转化为一个点对点问题，将所得结果作为邻近极值法的初始值并进行精确计算。最后，描绘了最优变轨过程。
