摘要：When the wing of Oblique Wing Aircraft(OWA) is skewed, the center of gravity, inertia and aerodynamic characteristics of the aircraft all significantly change, causing an undesirable flight dynamic response, affecting the flying qualities, and even endangering the flight safety. In this study,the dynamic response of an OWA in the wing skewing process is simulated, showing that the threeaxis movements of the OWA are highly coupled and present nonlinear characteristics during the wing skewing. As the roll control efficiency of the aileron decreases due to the shortened control arm in an oblique configuration, the all-moving horizontal tail is used for additional roll and the control allocation is performed based on minimum control energy. Given the properties of pitchroll-yaw coupling and control input and state coupling, and the difficulty of establishing an accurate aerodynamic model in the wing skewing process due to unsteady aerodynamic force, a multi-loop sliding mode controller is formulated by the time-scale separation method. The closed-loop simulation results show that the asymmetric aerodynamics can be balanced and that the velocity and altitude of the aircraft maintain stable, which means that a smooth transition is obtained during the OWA's wing skewing.

摘要：Plenty of dams in china are in danger while there are few effective methods for underwater dam inspections of hidden problems such as conduits,cracks and *** dam safety inspection remotely operated vehicle(DSIROV) is designed to solve these problems which can be equipped with many advanced sensors such as acoustical,optical and electrical sensors for underwater dam inspection.A least-square parameter estimation method is utilized to estimate the hydrodynamic coefficients of DSIROV,and a four degree-of-freedom(DOF) simulation system is *** architecture of DSIROV's motion control system is introduced,which includes hardware and software *** hardware based on PC104 BUS,uses AMD ELAN520 as the controller's embedded CPU and all control modules work in VxWorks real-time operating *** flow of the motion system of DSIROV,automatic control of dam scanning and dead-reckoning algorithm for navigation are also *** reliability of DSIROV's control system can be verified and the control system can fulfill the motion control mission because embankment checking can be demonstrated by the lake trials.

摘要：Searching for the optimal cabin layout plan is an efective way to improve the efciency of the overall design and reduce a ship’s operation *** multitasking states of a ship involve several statuses when facing diferent missions during a voyage,such as the status of the marine supply and emergency *** human fow and logistics between cabins will change as the state *** ideal cabin layout plan,which is directly impacted by the above-mentioned factors,can meet the diferent requirements of several statuses to a higher *** deviations exist in the quantifcation of human fow and ***,uncontrollability is present in the fow situation during actual *** coupling of these deviations and uncontrollability shows typical uncertainties,which must be considered in the design ***,it is important to integrate the demands of the human fow and logistics in multiple states into an uncertainty parameter *** research considers the uncertainties of adjacent and circulating strengths obtained after quantifying the human fow and *** numbers are used to integrate them,a two-layer nested system of interval optimization is introduced,and diferent optimization algorithms are substituted for solving *** comparison and analysis of the calculation results with deterministic optimization show that the conclusions obtained can provide feasible guidance for cabin layout scheme.

摘要：The radar cross section (RCS) of a sort of corrugated screen were simulated with the multilevel fast multipole method (MLFMM). The results of simulation and test agreed very well. Compared with plate, it can obviously reduce backscattering field at the normal direction. Finally, the RCS of a dihedral angle consisted of a corrugated screen and a plate was presented also.