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Optimal Matching Analysis of Net Buoyancy and Pitching Angle for Underwater Gliders

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China Ocean Engineering 2022年第5期36卷 697-706页

作者： yanG Ming LIANG yan wang yan-hui yanG Shao-qiong Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin 300350China The Joint Laboratory of Ocean Observing and Detection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Control parameter optimization is an efficient way to improve the endurance of underwater gliders(UGs),which influences their gliding efficiency and energy *** paper analyzes the optimal matching between the net buoyancy and the pitching angle and proposes a segmented control strategy of *** optimization of this strategy is established based on the gliding range model of UG,which is solved based on the approximate model,and the variations of the optimal control parameters with the hotel load are *** optimization results indicate that the segmented control strategy can significantly increase the gliding range when the optimal matching between the net buoyancy and the pitching angle is reached,and the increase rate is influenced by the hotel *** gliding range of the underwater glider can be increased by 10.47%at a hotel load of 0.5 *** optimal matching analysis adopted in this study can be applied to other UGs to realize endurance improvement.

关键词： optimal matching analysis underwater glider approximate model technology gliding range model

Scheme for Implementing Quantum Search Algorithm in a Cluster State Quantum Computer

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Communications in Theoretical Physics 2008年第6期49卷 1487-1490页

作者： wang yan-hui ZHANG Yong Department of Physics Hunan University of Science and Technology Xiangtan 411201 China Key Laboratory for Quantum Information and Measurements and Department of Physics Tsinghua University Beijing 100084 China

Using cluster state and single qubit measurement one can perform the one-way quantum computation. Here we give a detailed scheme for realizing a modified Grover search algorithm using measurements on cluster state. We give the measurement pattern for the cluster-state realization of the algorithm and estimated the number of measurement needed for its implementation. It is found that O（2^3n/^2n^2） number of single qubit measurements is required for its realization in a cluster-state quantum computer.

关键词： cluster state long algorithm control-phase gate measurement pattern

Analysis of Laser-Diode and Lamp Optical Pumping for a Rubidium Beam

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Chinese Physics Letters 2013年第2期30卷 69-73页

作者： GUO Jian wang yan-hui Institute of Quantum Electronics School of Electronics Engineering and Computer SciencePeking UniversityBeijing 100871 Department of Applied Electronic Engineering School of Software and MicroelectronicsPeking UniversityBeijing 102600

The time evolution of populations of the ground state hyperfine Zeeman levels of ^(87)Rb atoms is analyzed using the Runge-Kutta method for the case that a rubidium beam is optically pumped,under different conditions of polarization,with a weak monochromatic laser and an ^(87)R *** the base of the results above,the least estimated laser and ^(87)R lamp power for the best population inversion is obtained,aiding further investigations.

关键词： polarization pumped laser

Motion Analysis and Trials of the Deep Sea Hybrid Underwater Glider Petrel-Ⅱ

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China Ocean Engineering 2017年第1期31卷 55-62页

作者： LIU Fang wang yan-hui WU Zhi-liang wang Shu-xin Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China Yichang Research Institute of Testing Technology Yichang 443003China

A hybrid underwater glider Petrel-II has been developed and field tested. It is equipped with an active buoyancy unit and a compact propeller unit. Its working modes have been expanded to buoyancy driven gliding and propeller driven level-flight, which can make the glider work in strong currents, as well as many other complicated ocean environments. Its maximal gliding speed reaches 1 knot and the propelling speed is up to 3 knots. In this paper, a 3D dynamic model of Petrel-II is derived using linear momentum and angular momentum equations. According to the dynamic model, the spiral motion in the underwater space is simulated for the gliding mode. Similarly the cycle motion on water surface and the depth-keeping motion underwater are simulated for the level-flight mode. These simulations are important to the performance analysis and parameter optimization for the Petrel-II underwater glider. The simulation results show a good agreement with field trials.

关键词： hybrid underwater glider dynamic model numerical simulation underwater vehicles

Stability Analysis of Hybrid-Driven Underwater Glider

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China Ocean Engineering 2017年第5期31卷 528-538页

作者： NIU Wen-dong wang Shu-xin wang yan-hui SONG yang ZHU Ya-qiang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin University The Joint Laboratory of Ocean Observing and Detecting Qingdao National Laboratory for Marine Science and Technology

Hybrid-driven underwater glider is a new type of tmmanned underwater vehicle, which combines the advantages of autonomous underwater vehicles and traditional underwater gliders. The autonomous underwater vehicles have good maneuverability and can travel with a high speed, while the traditional underwater gliders are highlighted by low power consumption, long voyage, long endurance and good stealth characteristics. The hybrid-driven underwater gliders can realize variable motion profiles by their own buoyancy-driven and propeller propulsion systems. Stability of the mechanical system determines the performance of the system. In this paper, the Petrel-II hybrid-driven underwater glider developed by Tianjin University is selected as the research object and the stability of hybrid-driven underwater glider unitedly controlled by buoyancy and propeller has been targeted and evidenced. The dimensionless equations of the hybrid-driven underwater glider are obtained when the propeller is working. Then, the steady speed and steady glide path angle under steady-state motion have also been achieved. The steady-state operating conditions can be calculated when the hybrid-driven underwater glider reaches the desired steady-state motion. And the steady- state operating conditions are relatively conservative at the lower bound of the velocity range compared with the range of the velocity derived from the method of the composite Lyapunov function. By calculating the hydrodynamic coefficients of the Petrel-II hybrid-driven underwater glider, the simulation analysis has been conducted. In addition, the results of the field trials conducted in the South China Sea and the Danjiangkou Reservoir of China have been presented to illustrate the validity of the analysis and *** to show the feasibility of the method of the composite Lyapunov function which verifies the stability of the Petrel-II hybrid-driven underwater glider.

关键词： hybrid-driven underwater glider stability analysis numerical simulation field trials

On Maintenance of Inter-connectivity Among Multi-representations

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Journal of China University of Mining and Technology 2006年第4期16卷 494-499页

作者： wang yan-hui MENG Hao LIU Xiao-meng 3D Information Collection and Application Key Lab of Education Ministry School of Environmental Resources ＆ Tourism Capital Normal University Beijing 100037 China School of Public Policy ＆ Management Tsinghua University Beijing 100084 China

As the problems of conceptual and representational differences will arise among multi-representations, in- ter-connectivity maintenance among multi-representations exists as a foundational task in building multi-scale data model. Since the existing methods are still not satisfactory in practice, the inter-connectivity among multiple representa- tions can be only achieved if the multi-scale model is capable of explicitly inter-relating them and dealing with their differences. So, this paper firstly explores the relation among multiple representations from the same entity, such as multi-semantic, multi-geometry, multi-attributes, hierarchical semantic relations and so on. Based on these, this paper proposes aggregation-based semantic hierarchical matching rules (ASHMR) as the basis of tackling inter-connectivity among multi-representations, and defines the available hierarchical semantic knowledge, namely semantically equal, semantically related and semantically irrelevant. According to different change among multi-representations from dif- ferent types of objects, the applications and techniques of the corresponding hierarchy inter-connectivity matching crite- rion are explored. And taken the road intersections as examples, a case in point is given in details for describing the strategies of inter-connectivity maintenance, showing that this method is feasible to deal with inter-connectivity.

关键词： inter-connectivity multi-representation ASHMR hierarchical semantic relations data matching

Suppression of Amplitude Decoherence in Arbitrary n-Level Atom in -Configuration with Bang-Bang Controls

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Communications in Theoretical Physics 2008年第6期49卷 1432-1434页

作者： wang yan-hui LIU Xiao-Shu LONG Gui Lu Key Laboratory for Atomic and Molecular NanoSciences and Department of Physics Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China Institute of Microelectronics Tsinghua University Beijing 100084 China

In this paper, we give Bang-Bang （BB） decoupling schemes to suppress the amplitude decoherence in the five-and six-level atom systems in ≡-configuration. We generalize this scheme to the arbitrary level atom system... 详细信息

关键词： Bang-Bang control amplitude decoherence ≡-configuration

Attitude Coordination of Multi-HUG Formation Based on Multibody System Theory

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China Ocean Engineering 2017年第2期31卷 248-255页

作者： XUE Dong-yang WU Zhi-liang QI Er-mai wang yan-hui wang Shu-xin Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University Tianjin 300072 China School of Mechanical Engineering Tianjin University Tianjin 300072 China National Ocean Technology Center Tianjin 300112 China

Application of multiple hybrid underwater gliders （HUGs） is a promising method for large scale, long-term ocean survey. Attitude coordination has become a requisite for task execution of multi-HUG formation. In this paper, a multibody model is presented for attitude coordination among agents in the HUG formation. The HUG formation is regarded as a multi-rigid body system. The interaction between agents in the formation is described by artificial potential field （APF） approach. Attitude control torque is composed of a conservative torque generated by orientation potential field and a dissipative term related with angular velocity. Dynamic modeling of the multibody system is presented to analyze the dynamic process of the HUG formation. Numerical calculation is carried out to simulate attitude synchronization with two kinds of formation topologies. Results show that attitude synchronization can be fulfilled based on the multibody method described in this paper. It is also indicated that different topologies affect attitude control quality with respect to energy consumption and adjusting time. Low level topology should be adopted during formation control scheme design to achieve a better control effect.

关键词： hybrid underwater gliders (HUGs) formation attitude coordination multibody system Kane's equation

Field emission properties of amorphous GaN ultrathin films fabricated by pulsed laser deposition

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Science in China(Series F) 2009年第10期52卷 1947-1952页

作者： wang FengYing wang RuZhi ZHAO Wei SONG XueMei wang Bo yan hui Laboratory of Thin Film College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

Amorphous gallium nitride （a-GaN） films with thicknesses of 5 and 300 nm are deposited on n-Si （100） substrates by pulsed laser deposition （PLD）, and their field emission （FE） properties are studied. It shows that compared with thicker （300 nm） a-GaN film, better FE performance is obtained on ultrathin （5 nm） a-GaN film with a threshold field of 0.78 V/μm, which is the lowest value ever reported. Furthermore, the current density reaches 42 mA/cm2 when the applied field is 3.72 V/μm. These experimental results unambiguously confirm Binh＇s theoretical analysis （Binh et al. Phys Rev Lett, 2000, 85（4）： 864-867） that the FE performance would be prominently enhanced with the coating of an ultra-thin wide band-gap semiconductor film.

关键词： field emission amorphous gallium nitride (a-GaN) pulsed laser deposition (PLD) work function