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In order to study the thermodynamic effects of highway construction in plateau areas on frozen soil corridors, starting from the current practice of the frozen soil disease remediation project in plateau areas from 2017 to 2019, the mechanism of highway disease occurrence was discussed. The analysis was carried out, and the frozen soil was treated by the simulation test method. The field tests were conducted to investigate the actual use of the thermal insulation board subgrade and gravel subgrade of the diseased section. The temperature field distribution law of the frozen soil corridor project under periodic fluctuation of the boundary temperature was explored. The representative road section observation data was adopted to predict the temperature variation. Thermal characteristics of permafrost engineering corridors were analyzed. Taking the Golmud-Lhasa highway as the research object, the research results show that the construction method of the highway through the plateau directly affects the thermodynamic characteristics of the permafrost corridor project. Effective strategies have been obtained to control temperature changes, reduce roadbed damage, and enhance the thermal characteristics of permafrost engineering corridors.

This article presents an adaptive attitude tracking controller with external disturbances and unknown inertia parameters. The similar skew-symmetric structure is extended from the autonomous case to the non-autonomous case. The non-autonomous similar skew-symmetric is chosen as the desired structure of the closed loop system for attitude controller design. Based on this structure, a novel adaptive backstepping scheme is proposed to design the attitude controller by taking full advantage of the symmetry and the positive definiteness of the inertia matrix. The attitude tracking precision is enhanced by employing the linear parameterized form of the external disturbance torques. Simulation results demonstrate the effectiveness of the proposed attitude controller.

Autonomous On-orbit Service (OOS) is one of the key issues in aerospace technology nowadays. Since multi-robot system, which consists of several low-cost and simple robots, can work more efficiently and robustly than a single and complicated robot, we consider introducing multi-robot system into autonomous OOS. This paper focuses on the topic of task planning in multi-robot system, and takes advantage of expert system to solve this problem. We develop a new expert system called KICNP-S and a simulation platform called JavaRobot, which can simulate a group of intelligent robots performing OOS corporately. The simulation results show that expert system is competent in solving task planning problem, and we only need to modify the knowledge database when conditions of tasks change. Finally, simulation of a simplified OOS task is presented in which up to 13 robots repair a breakdown satellite.

This paper presents a mixed H 2 /H ∞ , state feedback control and its application to airborne dispenser pitch-axis autopilot design. Linear matrix inequality conditions that depend only on the vertices of polytope are given for existence of a stabilizing gain scheduled state feedback for linear parameter-varying system in convex polytopic domain, and the solution of the controller is given. The proposed method has the potential to yield less conservative results where the parameters involved can be measured or estimated online because some additional free variables are introduced to LMIs. The augmented system of airborne dispenser pitch-axis is modeled with mixed sensitivity method, applying the proposed method, good transient performance, good steady performance and good capability of disturbance rejection are readily achieved.

Public transportation intelligent dispatching system (PTIDS) is the most important subsystem in advanced public transportation system (APTS). In order to realize intelligent dispatching, the dispatcher must determine the headway and dispatching form for a certain transit vehicle. As we know, the headway is relatively stable for some certain time period since the passenger flow changes according to regularity. However, the dispatching form must be determined according to the real time passenger flow. This paper proposes that the principle of automatic creating of a transit vehicle's dispatching form for the first time. Then, a new automatic creating method based on BP (backpropagation) neural network is introduced, which can make sure that the dispatching form can be created in a short time. The case study in Line 306 of Changchun, a metropolitan city of China, has proved that the method proposed In this paper is application.