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Performance Measures Analysis of Admission Control Scheme Model for Wireless Network, Described by a Queuing System Operating in Random Environment 10

Performance Measures Analysis of Admission Control Scheme Mo...

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10th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT) - Emerging Technologies for Connected Society

作者： Adou, Yves Markova, Ekaterina Gudkova, Irina RUDN Univ Peoples Friendship Univ Russia Dept Appl Probabil & Informat 6 Miklukho Maklaya St Moscow 117198 Russia Russian Acad Sci Fed Res Ctr Comp Sci & Control Inst Informat Problems 44-2 Vavilova Str Moscow 119333 Russia

ISBN: (纸本)9781538693605

According to the latest data from the leading participants in the telecommunications market, such as Cisco Systems, the volume of traffic generated in modern wireless networks is increasing exponentially. The rapid growth of traffic, which appears in the context of providing a wide range of high-quality multimedia services to mobile network users leads to a lack of available radio spectrum. This is becoming a major problem in the development of modern wireless technologies. Mobile network operators offer various methods for solving this problem, such as the frameworks LAA and LSA, which allow more efficient use of available resources in the frequency band. In addition, as part of the implementation of various technologies to provide users services with the required level of QoS, mechanisms for managing radio resources, such as reducing the downlink power and interrupting users services can be applied. Models implementing such mechanisms can be described in the form of a queuing system with unreliable servers. This paper analyzes the performance metrics of a possible scheme for accessing the radio resources of a wireless network implemented through a mechanism for reducing the downlink power and interrupting user service. The mechanism itself is described in the form of a queuing system with unreliable servers, that are affected by a random environment.

关键词： queuing system random environment service interruption power limitation recursive algorithm blocking probability interruption probability mean bit rate

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Optimal equiripple comb FIR filters

Optimal equiripple comb FIR filters

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7th IASTED International Conference on Signal and Image Processing

作者： Zahradník, P Vlcek, M Czech Tech Univ Dept Telecommun Engn CZ-16627 Prague Czech Republic

ISBN: (纸本)0889865167

A novel analytical design method for highly selective digital optimal equiripple comb FIR filters is presented. The equiripple comb FIR filters are optimal in the Chebyshev sense. The number of notch bands, the width of the notch bands and the attenuation in the passbands can be independently specified. The degree formula and the differential equation for the generating polynomial of the filter is presented. Based on the differential equation, a fast simple algebraic recursive procedure for the evaluation of the impulse response of the filter is described. Its arithmetic robustness outperforms by far the known analytical design method. Highly selective equiripple comb FIR filters with thousands of coefficients can be designed. One example demonstrates the efficiency of the filter design.

关键词： FIR comb filter narrow band optimal filter equiripple approximation analytical design recursive algorithm

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Research and Implementation on the Cloud of Chinese Letter

Research and Implementation on the Cloud of Chinese Letter

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International Conference on Information Science, Automation and Material System

作者： An, Junxiu CUIT Sch Software Engn Chengdu 610025 Peoples R China

ISBN: (纸本)9783037850817

The Chinese word clouds can view the Chinese documents based on users' input or URL web sites, in accordance with the appearing frequency of words in the documents to generate a multi-state performance image, similar to the cloud images, namely, "word cloud". This system first obtains Chinese documents users view, cuts up words to the documents, then counts the frequency of each word, and finally puts the words on the appropriate framework based on the high or low word frequency, showing an effect of "word cloud". This system uses the hash algorithm making the output fonts not overlap, and generates personalized display images of Chinese word clouds, which makes users quickly understand the key information in Chinese documents and presents to users the different visual feelings. With the advent of mass storage of information, people can be more convenient, quick and free search the literature and news facts from the Internet. But searching for a keyword, it can display a broad array of Web Cache. This result wastes a lot of time to read text messages and find the required information. Therefore, how to directly and quickly grasp key information and focus of articles is our research subject. The software based on statistics usually need complex assignment and standard formulas to analysis, formation of highly professional graphic. Commonly used graphical text editor provide users with the weighted ratio and other aspects of visual experience, with strong and practical of research and guidance. But it does not implement the important function that directly convert text to graphics, and to provide readers who search for mass of information with a more intuitive experience, so we come up with the Chinese word cloud system. Chinese word cloud system based on the search engine technology, by utilizing text preprocessing, Chinese word segmentation, statistical word frequency, Java dynamic random display technologies and so on, achieve the display of Chinese word cloud. It

关键词： Chinese word clouds divided word word frequency HashMap hash recursive algorithm

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3D Motion Estimation from a Stereo Image Sequence Using Dual-Sequential-Kalman-Filter

3D Motion Estimation from a Stereo Image Sequence Using Dual...

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IEEE International Workshop on Imaging Systems and Techniques

作者： Yang, Ming Zhong, Xiaoqing Yang, Wei Huo, Ju Harbin Inst Technol Control & Simulat Ctr Harbin 150006 Heilongjiang Pr Peoples R China

ISBN: (纸本)9781424434824

Aiming at solving the coupling and time-consuming problem in motion estimation from images, a recursive estimator comprised of two sequential Kalman filters is proposed. 3D motion of a rigid object can be decomposed into translation of a point fixed on the object, called rotation center, and rotation w.r.t. this point. The rotational parameters are proved to be separate with the others, which means the motion has the potential to be decoupled. Viewing the moving object as a dynamic system, called moving object system, motion estimating is formulated as a state estimation problem. Decoupling the moving object system into two sub-systems, then the dual-sequential-Kalman-filter can be designed to estimate the states of the moving object system, thus a high dimension filter is replaced with two reduced ones. As time cost in computing depends on the third power of the dimension of the estimator, the time-consuming problem is solved partly. The performance of dual-sequential-Kalman-filter is illustrated using both simulated and real image sequences, two important merits, accuracy and robustness, are presented with the experiment results.

关键词： computer vision motion estimation motion decoupling recursive algorithm motion from stereo images

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recursive Solution of Systems Modeled by State Space and Multi-Delay Systems via First and Second Order Taylor Series 2

Recursive Solution of Systems Modeled by State Space and Mul...

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2nd International Conference on Control, Instrumentation, Energy & Communication (CIEC)

作者： Ghosh, Suchismita Deb, Anish Sarkar, Gautam MCKV Inst Engn Dept Elect Engn Howrah India Univ Calcutta Dept Appl Phys Kolkata India

ISBN: (纸本)9781509000357

The paper presents a recursive method using Taylor series to solve the states of time invariant control systems with and without delay. First of all, the Taylor series, both first and second order, are utilized to solve the state equation of a linear time invariant (LTI) system recursively. Subsequently, a recursive algorithm is proposed for solving an LTI system with delay. The states of the system solved using Taylor series are compared with exact solutions. The approach is much simpler than other established methods, and also, it proves to be reasonably accurate. The recursive algorithm presented avoids the use of any delay matrices. As expected, for same number of recursion steps, the second order Taylor series solution proves to be more efficient than the first order Taylor series approach. Examples are treated and the results obtained are presented via tables and graphs.

关键词： multi-delay system recursive algorithm state space Taylor series time invariant system

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recursive Dynamics for Free Flying Systems with Active and Passive Joints

Recursive Dynamics for Free Flying Systems with Active and P...

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2nd International Conference on Modelling and Simulation

作者： Shao, Bing Wu, Hongtao Nanjing Univ Aeronaut & Astronaut Coll Mech & Elect Engn Nanjing 210016 Peoples R China

ISBN: (纸本)9781846260629

Lie groups and Lie algebras are used to describe the dynamics of under-actuated free flying systems. The Newton-Euler inverse dynamics is promoted to contain the active and passive joints. At the same time, the dynamical modeling method of space systems with active and passive joints is built. This method can be used to model chain and tree topology space systems. It can also be used to model beam like flexible multibody systems which are established by finite segment method with highly efficiency. Results show that dynamics described with Lie groups and Lie algebras are helpful in high efficient dynamics modeling. The dynamical expressions are concise and clear.

关键词： free flying system dynamics Lie groups and Lie algebras recursive algorithm active and passive joints

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ASSEMBLY HIERARCHY GENERATION FOR ASSEMBLY SYSTEM DESIGN FOR A PRODUCT FAMILY 11

ASSEMBLY HIERARCHY GENERATION FOR ASSEMBLY SYSTEM DESIGN FOR...

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11th ASME International Manufacturing Science and Engineering Conference (MSEC)

作者： Jiang, Zhengqian Wang, Hui Florida State Univ Dept Ind & Mfg Engn Tallahassee FL 32306 USA

ISBN: (纸本)9780791849903

Increased demand on product variety entails a flexible assembly system for product families which can be quickly configured and reconfigured in a responsive manner to deal with various product designs. Development of such a responsive assembly system requires an in-depth understanding of the impact of product family design on assembly system performance. In this paper, the linkage between the product family design and assembly systems is characterized by an assembly hierarchy model, which reflects a hierarchical relationship among all possible sub-assemblies and components, assembly tasks, and material flow among the tasks. Our prior research developed a recursive algorithm to generate all assembly hierarchy candidates for one single product based on its liaison graph without redundancy. These generated assembly hierarchies provide a structure to help efficiently explore optimal assembly system designs with reduced computational load. In this paper, the application of the assembly hierarchy generation algorithm will be extended to a product family by developing joint liaison graph model. Taking the advantage of the modular design of the product family, we proposed a concept of multi-level joint liaison graphs to overcome the computational challenge brought by assembly hierarchy generation for joint liaisons. Two case studies were conducted to demonstrate the algorithm.

关键词： Product family assembly hierarchy recursive algorithm assembly system design liaison graph joint liaison

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Reachable Set Estimation for Discrete-Time Nonlinear Systems Using Ellipsoidal Set-Membership Frameworks

Reachable Set Estimation for Discrete-Time Nonlinear Systems...

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AIAA Science and Technology Forum and Exposition (AIAA SciTech Forum)

作者： Bhattacharjee, Diganta Subbarao, Kamesh Bhaganagar, Kiran Univ Texas Arlington Dept Mech & Aerosp Engn Box 19018 Arlington TX 76019 USA Univ Texas San Antonio Dept Mech Engn San Antonio TX 78248 USA

ISBN: (数字)9781624106095

ISBN: (纸本)9781624106095

In this paper, we focus on ellipsoidal estimates of reachable sets for discrete-time nonlinear dynamical systems based on ellipsoidal set-membership techniques. To this end, we implement a set-membership filter that utilizes state dependent coefficient parameterization of the nonlinear dynamics. The set-membership filter has a correction-prediction form similar to the Kalman Filter and generates optimal (minimum 'size' based on the trace criteria) ellipsoids at the correction and prediction steps, containing the true state of the system. At every time step, the optimal prediction ellipsoid provides an estimate of the reachable set. Also, information from the filter is utilized to formulate a family of ellipsoids containing the reachable set at each time step. The minimum 'size' ellipsoid (based on the trace criteria or the log-determinant criteria) of this family is identified as another ellipsoidal estimate of the reachable set. Simulation examples are included to illustrate results corresponding to the two estimates.

关键词： Nonlinear Systems Kalman Filter Nonlinear Dynamics recursive algorithm Convex Optimization K Capture MATLAB

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Multiresolution-Based 3-D Terrain Estimation algorithms for Complex Urban Environments

Multiresolution-Based 3-D Terrain Estimation Algorithms for ...

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AIAA Science and Technology (SciTech) Forum and Exposition

作者： Vergara, Pedro Tiwari, Madhar Chavez, Andres Prazenica, Richard Henderson, Troy Embry Riddle Aeronaut Univ Daytona Beach FL 32114 USA

ISBN: (数字)9781624105784

ISBN: (纸本)9781624105784

This paper investigates the development of multiresolution-based terrain estimation algorithms, focusing on complex three-dimensional urban environments. The algorithms generate functional terrain representations from point cloud data obtained from the processing of onboard vision and/or LIDAR sensors. Two classes of multiresolution algorithms are considered in this work. First, mathematical learning methods are developed and implemented to generate adaptive terrain representations in terms of piecewise-constant multiresolution basis functions. These algorithms have been applied in previous work for terrain estimation over two-dimensional domains and are extended in this paper for three-dimensional domains, resulting in terrain representations in terms of multiresolution occupancy grids. The second class of algorithms corresponds to global-orthogonal mapping (GLO-Map) algorithms, which have been developed in previous work to generate representations over two-dimensional domains in terms of smooth orthogonal functions with varying resolution. Representative terrain mapping examples are provided using simulated LIDAR data from a virtual urban environment as well as processed 3-D LIDAR data collected from a UAV flying through a representative obstacle environment.

关键词： LIDAR Sensor Path Planning recursive algorithm Aeronautics Flight Data Satellites

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Predictive Stop-Loss Premiums

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ASTIN Bulletin 1993年第1期23卷 55-76页

作者： Hürlimann, Werner Switzerland

Based on a representation of the aggregate claims random variable as linear combination of counting random variables, a linear multivariate Bayesian model of risk theory is defined. In case of the classical risk theoretical assumptions, that is conditional Poisson likelihood counting variates and Gamma structural density, the model is shown to identify with a Bayesian version of the collective model of risk theory. An interesting multivariate credibility formula for the predictive mean is derived. A new type of recursive algorithm, called three-stage nested recursive scheme, allows to evaluate the predictive density and associated predictive stop-loss premiums in an effective way. © 1993, International Actuarial Association. All rights reserved.

关键词： Aggregate claims Bayesian modelling collective risk theory recursive algorithm stop-loss

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