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2016 4th International Conference on Machinery,Materials and Information technology Applications(ICMMITA 2016)

作者： Yu GUO Junting WU Ke-wei YANG Lixin Yu College of Information System and Management National University of Defense Technology Science and Technology on Special System Simulation Laboratory Beijing Simulation Center

ISBN: (纸本)9781510835467

Currently, Internet and big data as the representative of emerging technologies are widely penetrated into every aspect of the high-end equipment manufacturing industry. Considering the characteristics of multi-source, personalized and potential for high-end equipment, this paper focuses on requirement elicitation in the background of Internet, and proposes a high-end equipment requirement elicitation model based on requirement classification, which stands on the perspective of management to study the high-end equipment requirement elicitation. First, we classify the user's need, and then different technical means are taken orienting different types of needs. In this paper, according to users' master degree of requirement, requirements can be divided into instant user requirement and potential user requirement. For instant user requirement, we design a requirement interaction platform based on Internet;For potential user requirement, a requirement mining model based on the open source information of the Internet is established. Eventually, a complete user requirement program is integrated. In conclusion, the idea of classifying the requirements provides a new perspective on requirement elicitation of high-end equipment.

关键词： high-end equipment Internet requirement elicitation requirement classification

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Profiling and analysis of object lazy allocation in Java programs

Profiling and analysis of object lazy allocation in Java pro...

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ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing (SNPD)

作者： Jianjun Shi Weixing Ji Lulu Zhang Yujin Gao Han Zhang Duzheng Qing School of Computer Science Beijing Institute of Technology Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China

Lazy allocation strategy allows the memory management system to defer the space allocation action of objects until they are being accessed. This paper investigates the potential benefits of a lazy allocator for Java applications. A heap tracing tool is implemented by instrumenting an existing Java virtual machine HotSpot, which records useful object manipulating events at runtime. By profiling and analyzing a large number of benchmarks, we show the potential dynamic memory management optimization opportunity in Java programs. We also designed a simulation system to demonstrate the actual effects of a lazy allocator.

关键词： Resource management Java Benchmark testing Memory management Virtual machining Color Runtime

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A Robust Path Following Controller for a Small Unmanned Aerial Vehicle with Constrained Parameters Optimized

A Robust Path Following Controller for a Small Unmanned Aeri...

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International Conference on Information science and Control Engineering (ICISCE)

作者： Yang Chen Chaolei Wang School of Mechanical and Electrical Engineering Longyan University Longyan China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China

ISBN: (纸本)9781509025367

This paper proposes a nonlinear controller that allows the unmanned air vehicle (UAV) to follow a predefined path. The controller only needs the information of the inertial speed of the UAV and the distance between the vehicle and the desired path. In order to improve the performance of the controller, a parameter of the controller is optimized by using the concept of model predictive control (MPC). Lyapunov stability arguments are used to demonstrate that the path following error will be regulated to zero, even in the presence of wind disturbances. simulation results in Matlab are given to show the effectiveness of the controller. The simulation results show that the proposed path following controller with parameter optimized by MPC (PLC_MPC) which takes the advantages of the predictive ability of the MPC and the simple structure of the normal path following controller (PLC) has better path following performance than that by using the PLC method.

关键词： Unmanned aerial vehicles Mathematical model Optimization Stability analysis Trajectory Lyapunov methods

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Enhanced null message algorithm for hybrid parallel simulation systems with large disparity in time step

Enhanced null message algorithm for hybrid parallel simulati...

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International Workshop/Symposium on Distributed simulation and Real-Time Applications (DS-RT)

作者： Bin Wang Yanlong Zhai Zishuo Wang Han Zhang Duzheng Qing Beijing Engineering Research Center of Massive Language Information Processing and Cloud Computing Applications Bijing Institute of Technology Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center China

ISBN: (纸本)9781509035069

Modeling and simulation has received significant attention over the years for its ability to understand and transform real world systems. With the increasing of complexity and scale of the simulated systems, more computational power is required. Parallel discrete event simulation(PDES) is an important technology to integrate parallel computing into modeling and simulation. Time synchronization algorithm is the core of PDES, which determines the correctness and efficiency of the simulation. Traditional conservative synchronization algorithms, such as Chandy-Misra-Bryant(CMB) null message algorithm, use null message to synchronize the state and avoid deadlock among logical processes(LPs). But hybrid simulation systems contains both continuous models and discrete models, continuously changing states is typically modeled using time steps in hybrid simulation system. Therefore, hybrid systems with large disparity in time step are very common in real simulation systems. However, current conservative synchronization algorithm has not been fully investigated for this type of simulation systems and will generate massive synchronization messages. This paper proposed an enhanced null message algorithm for hybrid simulation systems with large disparity in time step. It extended the CMB algorithm by adding simulation time in null message request messages. This could significantly reduce the number of synchronization messages. Experimental results showed that our synchronization algorithm outperforms the CMB algorithm by reducing a great number of synchronization messages.

关键词： Synchronization Computational modeling Atmospheric modeling Adaptation models system recovery Ports (Computers) Complex systems

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A generation algorithm of Latin hypercube sampling based on original sampling points 27

A generation algorithm of Latin hypercube sampling based on ...

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27th European Modeling and simulation Symposium, EMSS 2015

作者： Liu, Zhizhao Li, Wei Yang, Ming Xu, Jun Qing, Duzheng Control and Simulation Center Harbin Institute of Technology Harbin150080 China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing100854 China

ISBN: (纸本)9788897999485

In order to utilize original sampling points as many as possible to construct a Latin Hypercube Sampling (LHS), a generation algorithm of LHS is proposed. The original sampling can be an arbitrary sampling and the new sampling is a LHS strictly. As the high structure of LHS, only part of original sampling points can be used for LHS. There are several problems including how to select the reserved original sampling points and generate the new ones if necessary. Matrices are used to describe the original sampling points and the original sampling points are reserved based on an adjacent matrix. The new sampling points are generated by a subtraction rule. Numerical experiments show that the generation algorithm is effective and saves a lot of running time for simulation systems.

关键词： Geometry

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Probabilistic robust control strategy for gust load alleviation 16

Probabilistic robust control strategy for gust load alleviat...

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16th International Forum on Aeroelasticity and Structural Dynamics, IFASD 2015

作者： Dai, Yuting Yang, Chao Wang, Chaolei School of Aeronautic Science and Engineering Beihang University Beijing100854 China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing100854 China

The aeroelastic model for a wing in the time domain is constructed with continuous wind gust and structural uncertainties. The H∞ optimal method and μ synthesis are applied to the robust control law design for gust load alleviation (GLA) problem. Specifically, with instability risk introduced in the uncertain model, the GLA factor can be largely increased. The instability probability for a uncertain system and nominal GLA factor are trade-off to get a higher performance and acceptable instability risk. At the same flow velocity, the stability robustness is decreased while the nominal gust load can be largely alleviated. Vise visa, though the nominal aeroelastic model is stable at all the velocities between 10 m/s to 30 m/s, the instability risk increased with the GLA factor ascending. Results indicate that with introducing a 0.2% instability risk, the nominal gust load can be alleviated by 24.5%.

关键词： Economic and social effects

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Adaptive Assignment for Quality-Aware Mobile Sensing Network with Strategic Users

Adaptive Assignment for Quality-Aware Mobile Sensing Network...

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IEEE International Conference on High Performance Computing and Communications (HPCC)

作者： Ning An Rui Wang Zhongzhi Luan Depei Qian Jihong Cai Han Zhang Sino-German Joint Software Institute Beihang University Beijing China Science and Technology on Special System Simulation Laboratory Beijing China

Mobile crowdsourcing with smartphones is a novel paradigm that collects distributed data efficiently. Millions ofcrowdsourcing tasks should be assigned and performed every day. In order to give good service quality for mobile sensing applications, a practical assignment approach is indispensable for a task platform to select appropriate users. This paper considers heterogeneous task assignment problem in the mobile sensing network that cannot label users. We consider the following scenario: a requester posts a set of tasks onto the platform, the platform selects a subset of proper smartphones to complete the different kinds of tasks under a budget constraint, all users inthese transactions are strategic for maximizing their individual utility. The assignment approach should be designed to fight against strategic behaviors of smartphone users. We address this problem by introducing a novel mechanism for mobile sensing assignment based on the multi-armed bandit problem. Moreover, we present an adaptive algorithm to assign users according to the properties of task and which task they are good at. Finally, we evaluate the performance of our mechanism based on a real dataset, and the results demonstrate that proposed algorithm achieves better in high-quality assignment.

关键词： Sensors Smart phones Mobile communication Crowdsourcing Pricing Cameras Accelerometers

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Indoor visual navigation system based on paired-landmark for small UAVs

Indoor visual navigation system based on paired-landmark for...

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IEEE International Conference on Robotics and Biomimetics

作者： Tianmiao Wang Yicheng Zhang Chaolei Wang Jianhong Liang Han Gao Miao Liu Qinpu Guan Anqi Sun BeiHang University Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China Beihang University Beijing CN

ISBN: (纸本)9781479973989

This paper has presented an implementation of visual based non-GNSS navigation method for small VTOL (Vertically Taking-off and Landing) UAV (Unmanned Aerial Vehicle). A novel method of constructing landmarks is described in detail. It uses a pair of landmarks instead of the general landmark which usually is a single geometry or coding image. The paired-landmark method inherits general landmark methods' advantages of low-cost, high-efficiency and the ability of absolute positioning. And it also solves the problem of requiring too much different characteristic landmarks when handling large area navigation. The paired-landmark method has been verified by a real parameter simulation environment. Real flight experiment is also carried out to test the effectiveness and performance of the paired-landmark navigation method. It can be concluded that, besides achieved the expected positioning precision, the proposed system also reduced the consumption of calculation and memory space.

关键词： Cameras Aircraft Aircraft navigation Visualization Atmospheric modeling Estimation

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NECESSARY AND SUFFICIENT CONDITIONS FOR DEADLOCKS IN FLEXIBLE MANUFACTURING systemS BASED ON A DIGRAPH MODEL

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Asian Journal of Control 2008年第2期6卷

作者： Wenle Zhang Robert P. Judd Paul Deering School of Electrical Engineering and Computer Science Ohio University Athens OH 45701. Dr. Judd has over twenty years of experience as an educator researcher and consultant in system simulation discrete event controls and systems integration. Dr. Judd has received over thirty research grants totaling over $3500000. His funding has come from both industrial and governmental sources. He is the author or co-author of over a hundred published papers in journals and conferences. He also wrote a book chapter devoted to integrating manufacturing design tools and edited a special issue of the International Journal of Computer Integrated Manufacturing dedicated to intelligent manufacturing systems. Dr. Judd holds a patent on simulation software integration. Russ College of Engineering and Technology Ohio University Athens OH 45701.

As typical discrete event systems, flexible manufacturing systems have been extensively studied in such aspects as modeling, control and performance analysis. One important topic in the study of such systems is the deadlock detection, prevention and avoidance. In the past decade, two major modeling formalisms, i.e., Petri nets and digraphs, have been adopted for developing deadlock control policies for flexible manufacturing systems. In this paper, the concepts of slack, knot, order and effective free space of circuits in the digraph are established and used to concisely and precisely quantify the sufficient conditions for a system state to be live. Necessary conditions for this liveness is quantified for a special class of system states - called evaluation states. The significance of the result is that the conditions are true for avoiding both primary deadlocks and impending deadlocks that are arbitrary steps away from a primary one, whereas only second level deadlocks have been studied in the literature. Examples are provided to illustrate the method.

关键词： Flexible manufacturing systems deadlock avoidance deadlock prevention petri net digraph

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PERFORMANCE OF A PRIORITIZED ON-BOARD BASEBAND SWITCH FOR A MULTISERVICE MULTIBEAM SATELLITE

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INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS 1994年第3期12卷 283-297页

作者： BOHM, S ELHAKEEM, AK HACHICHA, M Department of Electrical and Computer Engineering Concordia University 1455 De Maisonneuve Blvd. West Montreal H3A 1M8 Canada Was born in Montreal Canada on 14 September 1966. He received the B. Eng. degree in electrical engineering from Concordia University Montreal Canada in 1989. He is at present completing the M.A.Sc. degree in electrical engineering at Concordia University. (S'75–S'79–M'79–SM'86) received the Ph.D. degree from Southern Methodist University Dallas TX in 1979. He spent the next two years working as a Visiting Professor in Egypt after which he moved to Ottawa Canada in 1982. He assumed teaching and research positions in Carleton and Manitoba Univerities and later moved to Concordia University Montreal Canada in 1983 where he is now a Professor in the Electrical and Computer Engineering Department. He has published numerous papers in IEEE and international journals in the areas of spread spectrum and networking. He is a well-known expert in these areas and serves as a consultant to many companies. His current research interests include wide-band metropolitan networks switching architectures and performance of on-board multibeam satellites acquisitionless CDMA networks code distribution and orthogonalization of CDMA signals responsive congestion control for ATM-based networks ARQ techniques and investigation of the novel SUGAR CDMA systems in fading channels. Dr. Elhakeem is a Senior Member of the Canadian Electrical Engineering Society and Armed Forces Association. He has chaired numerous technical sessions in IEEE Conferences was the Technical Program Chairman for IEEE Montech 1986 Montreal Canada. Dr. Elhakeem is the key guest editor of theIEEE Journal of Selected Areas in Communicationsfor the May June issues 1993 covering CDMA networks. Advanced Technology & Networks VISTAR Telecommunications Inc. Ottawa Ontario K1G 3J4 Canada An Associate Director of Advanced Technology & Networks Group VISTAR Telecommunications Inc. Ottawa Canada. He is also an Adjunct Pr

In this paper, we study the performance of a prioritized on-board baseband switch in conjunction with a multibeam satellite handling integrated services. The services considered for the analysis include voice, video, file transfer and interactive data. The prioritized switch uses both input and output buffering, switch speed-up as well as a two-phase head-of-line resolution algorithm, in order to reduce the buffer loss while maintaining acceptable user delays. The minimum required buffer capacity and switch speed-up for each service in a prioritized environment are found under uniform traffic conditions. It is shown that under uniform traffic conditions, only minimal buffering and switch speed-up are needed even for the lowest priority users. The performance dependence on the switch size is also substantially reduced with head of line resolution and buffering even in a prioritized environment.

关键词： SWITCH ON-BOARD BASEBAND MULTIBEAM PRIORITIZED HEAD-OF-LINE UNIFORM LOAD SPEED-UP

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