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Tribological performance of organic cadmium compound as lubricant additive

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中国有色金属学会会刊：英文版 2004年第z1期14卷 374-378页

作者： HU Jian-qiang XIE Feng ZHU Huan-qin ZHEN Fa-zheng YAO Jun-bing Department of aviation Oil Air Force Logistics Institute Xuzhou 221000 China Department of Aviation Oil Air Force Logistics Institute Xuzhou 221000 China Department of Aviation Oil Air Force Logistics Institute Xuzhou 221000 China Department of Aviation Oil Air Force Logistics Institute Xuzhou 221000 China First Department Aviation Oil Research Institute Beijing 100000 China

The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant grease synthesized compared with some commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and is better than other additives. The surface analytical tools such as scanning electron microscope (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectrometer (XPS) were used to investigate the topography, the compositions, and chemical states of some typical elements on the rubbing surface of worn *** and light topography of worn scar further confirms that the additive shows good antiwear capacities. The results of EDX and XPS analyses indicate that tribochemical mixed protective films consisting of atomic cadmium, sulphides, sulphates and phosphates are formed on the rubbing surface, which contribute to improving the tribological properties of lubricant and grease. Particularly, the soft cadmium film formed plays an important role in improving antiwear properties of oils. Finally, antiwear mechanism of the additive and formation scheme of atomic cadmium was proposed.

关键词： cadmium dipropyldithiophosphate additive extreme pressure antiwear mechanism

A uniform framework of projection and community detection for one-mode network in bipartite networks

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Chinese Physics B 2017年第12期26卷 636-646页

作者：吴果林顾长贵邱路杨会杰 Business School University of Shanghai for Science and Technology Shanghai 200093 China Faculty of Science Guilin University of Aerospace Technology Guilin 541004 China guangxi aviation logistics research center Guilin University of Aerospace Technology Guilin 541004 China School of Finance and Business Shanghai Normal University Shanghai 200234 China

Projection is a widely used method in bipartite networks. However, each projection has a specific application scenario and differs in the forms of mapping for bipartite networks. In this paper, inspired by the network-based information exchange dynamics, we propose a uniform framework of projection. Subsequently, an information exchange rate projection based on the nature of community structures of a network （named IERCP） is designed to detect community structures of bipartite networks. Results from the synthetic and real-world networks show that the IERCP algorithm has higher performance compared with the other projection methods. It suggests that the IERCP may extract more information hidden in bipartite networks and minimize information loss.

关键词： bipartite networks community projection information exchange

Throughput Capacity of a Container Terminal Considering the Combination Patterns of the Types of Arriving Vessels

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Journal of Shanghai Jiaotong university(Science) 2010年第1期15卷 124-128页

作者：丁以中 logistics research center Shanghai Maritime University

The throughput capacity of a container terminal is very important in planning and designing at container *** existing methods estimated the throughput capacity without considering its change resulting from the different combination patterns of the types of arriving vessels.A simulation model is established to estimate the throughput capacities of a container terminal under different combination patterns of the types of arriving *** shows that the throughput capacity of a container terminal is influenced by the utilization rates of the berth and quay cranes which result from the different combination patterns of the types of the arriving *** provides a practical approach to estimate the throughput capacity of a container terminal considering the types of the vessels,and it is also helpful for the decision makers to raise the throughputs of the container terminals by optimizing the combination patterns of the types of arriving vessels.

关键词： simulation container terminal throughput capacity utilization rate of the berth

An improved cellular automaton model considering the effect of traffic lights and driving behaviour

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Chinese Physics B 2011年第4期20卷 197-203页

作者：何红弟卢伟真董力耘 logistics research center and Shanghai Engineering research center of Shipping logistics Information Shanghai Maritime University Department of Building and Construction City University of Hong Kong Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

This paper proposes an improved cellular automaton model to describe the urban traffic flow with the consideration of traffic light and driving behaviour effects. Based on the model, the characteristics of the urban traffic flow on a single- lane road are investigated under three different control strategies, i.e., the synchronized, the green wave and the random strategies. The fundamental diagrams and time-space patterns of the traffic flows are provided for these strategies respectively. It finds that the dynamical transition to the congested flow appears when the vehicle density is higher than a critical level. The saturated flow is less dependent on the cycle time and the strategies of the traffic light control, while the critical vehicle density varies with the cycle time and the strategies. Simulated results indicate that the green wave strategy is proven to be the most effective one among the above three control strategies.

关键词： traffic flow cellular automaton control strategy vehicle density

Influence of Non-Axisymmetric Terms on Circumferentially Averaged Method in Fan/Compressor

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Journal of Thermal Science 2013年第1期22卷 13-22页

作者： Ke Wan Hailiang Jin Donghai Jin Xingmin Gui Aeroengine Numerical Simulation research center Beijing University of Aeronautics and Astronautics China aviation Powerplant research Institute

The governing equations are derived by circumferentially averaging the three-dimensional （3D） Navier-Stokes equations, which are solved using a time marching finite volume approach. Both Euler throughflow model and Navier-Stokes （N-S） throughflow model are employed to investigate the performance and flow fields of a highly loaded transonic single-stage fan ATS-2 and a four-stage fan. The results are compared with the experimental and three-dimensional computational results. It shows that the throughflow models can provide reasonable perform- ance characteristics and N-S throughflow model gives better predictions in endwall regions. A throughflow com- putation in which all the non-axisymmetric terms are included has been performed at off-design condition and the radial distributions of the flow field can be well described.

关键词： throughflow model circumferentiaily averaged non-axisymmetric terms fan

Unmanned air vehicle flow separation control using dielectric barrier discharge plasma at high wind speed

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Science China(Physics,Mechanics & Astronomy) 2014年第6期57卷 1160-1168页

作者： ZHANG Xin HUANG Yong WANG WanBo WANG XunNian LI HuaXing College of aviation Northwestern Polytechnical University China Aerodynamics research and Development center

The present paper described an experimental investigation of separation control of an Unmanned Aerial Vehicle(UAV)at high wind *** plasma actuator was based on Dielectric Barrier Discharge(DBD)and operated in a steady *** flow over a wing of UAV was performed with smoke flow visualization in theΦ0.75 m low speed wind tunnel to reveal the flow structure over the wing so that the locations of plasma actuators could be optimized.A full model of the UAV was experimentally investigated in theΦ3.2 m low speed wind tunnel using a six-component internal strain gauge *** effects of the key parameters,including the locations of the plasma actuators,the applied voltage amplitude and the operating frequency,were *** whole test model was made of aluminium and acted as a cathode of the *** results showed that the plasma acting on the surface of UAV could obviously suppress the boundary layer separation and reduce the model vibration at the high wind *** was found that the maximum lift coefficient of the UAV was increased by 2.5%and the lift/drag ratio was increased by about 80%at the wind speed of 100 m/*** control mechanism of the plasma actuator at the test configuration was also analyzed.

关键词： plasma actuator flow control dielectric barrier discharge unmanned air vehicle

Solid rocket propulsion technology for de-orbiting spacecraft

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Chinese Journal of Aeronautics 2022年第3期35卷 128-154页

作者： Adam OKNINSKI center of Space Technologies Lukasiewicz Research Network-Institute of AviationWarsaw 02-256Poland

This paper presents the topic of using solid rocket propulsion for de-orbiting spacecraft,in order to fulfil space debris mitigation *** benefits and disadvantages of using such means are discussed.A dedicated system can be implemented in the satellite design phase and shall be a key subsystem of platforms inserted into ***,semi-controlled and controlled de-orbit can be completed using solid rocket *** impact on the space debris environment is *** requirements for dedicated propellants and systems are *** the majority of presently developed rocket systems worldwide require high burn rates,several applications,including de-orbiting,benefit from solid propellants with decreased regression *** allows limiting spacecraft accelerations and loads during de-orbit ***,the requirement of minimising solid particle generation is *** technology from the Mercury and Gemini human spaceflight programmes,where de-orbit motors were used,is *** Soviet,American and Chinese film-return-capsule solid propellant retrorockets,enabling deorbit,are also presented.A detailed survey of current work worldwide on end-of-life disposal using solid propulsion is *** of developing dedicated systems are ***,an outlook on solid rocket motor utilisation for space debris mitigation is provided.

关键词： De-orbit De-orbiting technology End-of-life disposal Satellite propulsion system development Solid propellant Solid rocket motor Space debris mitigation Space traffic management

AN ANT COLONY ALGORITHM FOR YARD TRUCK SCHEDULING AND YARD LOCATION ASSIGNMENT PROBLEMS WITH PRECEDENCE CONSTRAINTS

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Journal of Systems Science and Systems Engineering 2013年第1期22卷 21-37页

作者： Zhaojie XUE Canrong ZHANG Lixin MIAO Wei-Hua LIN research center of Modern logistics Tsinghua Campusthe University Town Systems and Industrial Engineering Department University of Arizona

This paper examines the yard truck scheduling,the yard location assignment for discharging containers,and the quay crane scheduling in container *** into account the practical situation,we paid special attention to the loading and discharging precedence relationships between containers in the quay crane operations.A Mixed Integer Program（MIP） model is constructed,and a two-stage heuristic algorithm is *** the first stage an Ant Colony Optimization（ACO） algorithm is employed to generate the yard location assignment for discharging *** the second stage,the integration of the yard truck scheduling and the quay crane scheduling is a flexible job shop problem,and an efficient greedy algorithm and a local search algorithm are proposed. Extensive numerical experiments are conducted to test the performance of the proposed algorithms.

关键词： Container terminal yard truck scheduling yard location assignment quay crane scheduling precedence constraints ant colony optimization

Visual tracking using discriminative representation with l2 regularization

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Frontiers of Computer Science 2019年第1期13卷 199-211页

作者： Haijun WANG Hongjuan GE College of Civil aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China aviation Information Technology research and Development center Binzhou UniversityBinzhou 256603China

In this paper,we propose a novel visual tracking method using a discriminative representation under a Bayesian ***,we exploit the histogram of gradient (HOG)to generate the texture features of the target templates and ***,we introduce a novel discriminative representation and l2-regularized least squares method to solve the proposed representation *** proposed model has a closed-form solution and very high computational ***,a novel likelihood function and an update scheme considering the occlusion factor are adopted to improve the tracking performance of our proposed method. Both qualitative and quantitative evaluations on 15 challenging video sequences demonstrate that our method can achieve more robust tracking results in terms of the overlap rate and center location error.

关键词： visual tracking discriminative representation Bayesian framework closed-form solution