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Particle Swarm Optimization-Based Direct Inverse Control for Controlling the Power Level of the Indonesian Multipurpose Reactor

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SCIENCE AND TECHNOLOGY OF NUCLEAR INSTALLATIONS 2016年第5-31期2016卷 1-9页

作者： Pambudi, Yoyok Dwi Setyo Wahab, Wahidin Kusumoputro, Benyamin Univ Indonesia Dept Elect Engn Kampus Baru UI Depok 16424 Indonesia Natl Nucl Energy Agcy Indonesia BATAN Ctr Nucl Reactor Technol & Safety Puspiptek Area Serpong 15310 Tangerang Selat Indonesia

A neural network-direct inverse control (NN-DIC) has been simulated to automatically control the power level of nuclear reactors. This method has been tested on an Indonesian pool type multipurpose reactor, namely, Reaktor Serba Guna-GA Siwabessy (RSG-GAS). The result confirmed that this method still cannot minimize errors and shorten the learning process time. A new method is therefore needed which will improve the performance of the DIC. The objective of this study is to develop a particle swarm optimization-based direct inverse control (PSO-DIC) to overcome the weaknesses of the NN-DIC. In the proposed PSO-DIC, the PSO algorithm is integrated into the DIC technique to train the weights of the DIC controller. This integration is able to accelerate the learning process. To improve the performance of the system identification, a backpropagation (BP) algorithm is introduced into the PSO algorithm. To show the feasibility and effectiveness of this proposed PSO-DIC technique, a case study on power level control of RSG-GAS is performed. The simulation results confirm that the PSO-DIC has better performance than NN-DIC. The new developed PSO-DIC has smaller steady-state error and less overshoot and oscillation.

关键词： NUCLEAR reactors -- Control PARTICLE swarm optimization NEURAL networks (computer science) BACK propagation (Artificial intelligence) AUTOMATIC control computer algorithms

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High-precision identification of contextual information in location-aware engineering applications

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ADVANCED ENGINEERING INFORMATICS 2009年第4期23卷 483-496页

作者： Khoury, Hiam M. Kamat, Vineet R. Univ Michigan Dept Civil & Environm Engn Ann Arbor MI 48109 USA

This paper presents research that investigated algorithms for high-precision identification of contextual information in location-aware engineering applications. The primary contribution of the presented work is the design and implementation of a dynamic user-viewpoint tracking scheme in which mobile users' spatial context is defined not only by their position (i.e., location), but also by their three-dimensional head orientation (i.e., line of sight). This allows the identification of objects and artifacts visible in a mobile user's field of view with much higher accuracy than was possible by tracking position alone. For outdoor applications, a georeferencing based algorithm has been developed using the Global Positioning System (GPS) and magnetic orientation tracking devices [5] to track a user's dynamic viewpoint. For indoor applications, this study explored the applicability of wireless technologies, in particular Indoor GPS, for dynamic user position tracking in situations where GPS is unavailable. The objectives of this paper are to describe the details of the three-stage-algorithm that has been designed and implemented, and to demonstrate the extent to which positioning technologies such as GPS and Indoor GPS can be used together with high-precision orientation trackers to accurately interpret the fully-qualified spatial context of a mobile user in challenging environments such as those found on construction sites. The obtained results highlight the potential of using location-aware technologies for rapidly identifying and retrieving contextual information in engineering applications. (C) 2009 Elsevier Ltd. All rights reserved.

关键词： GLOBAL Positioning System ENGINEERING design PRECISION (Information retrieval) computer algorithms THREE-dimensional imaging WIRELESS communication systems

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The Jigsaw secure distributed file system

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computerS & ELECTRICAL ENGINEERING 2013年第4期39卷 1142-1152页

作者： Bian, Jiang Seker, Remzi Univ Arkansas Med Sci Div Biomed Informat Little Rock AR 72205 USA Embry Riddle Aeronaut Univ Dept Elect Comp Software & Syst Engn Daytona Beach FL USA

The Jigsaw Distributed File System (JigDFS) aims to securely store and retrieve files on large scale networks. The design of JigDFS is driven by the privacy needs of its users. Files in JigDFS are sliced into small segments using an Information Dispersal Algorithm (IDA) and distributed onto different nodes recursively. JigDFS provides fault-tolerance against node failures while assuring confidentiality, integrity, and availability of the stored data. Layered encryption is applied to each file segment with keys produced by a hashed-key chain algorithm. Recursive IDA and layered encryption enhance users' anonymity and provide a degree of plausible deniability. JigDFS is envisioned to be an ideal long-term storage solution for developing secure data archiving systems. (C) 2013 Elsevier Ltd. All rights reserved.

关键词： computer files DISTRIBUTION (Probability theory) computer users INFORMATION retrieval computer algorithms FAULT-tolerant computing DATA encryption (computer science)

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Efficient broadcasting using packet history in mobile ad hoc networks

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IET COMMUNICATIONS 2011年第15期5卷 2196-2205页

作者： Agathos, S. Papapetrou, E. Univ Ioannina Dept Comp Sci GR-45110 Ioannina Greece

Broadcasting is a key component of several networking mechanisms in mobile ad hoc networks. However, its traditional implementation suffers from resource consumption caused by message redundancy. Several efficient algorithms have been proposed to tackle this problem. Among them, the class of algorithms that construct on-demand a connected dominating set, known as dominant pruning, yields an improved performance. Dominant pruning algorithms capitalise on neighbourhood information and the previous hop of the broadcast message in order to minimise the set of nodes that forward a message. The proposed algorithm makes the observation that all the nodes, visited by a broadcast message, may be exploited in order to minimise the cost of broadcasting. The analysis of the proposed algorithm as well as extensive simulation results confirm the rationale behind the proposed approach and prove the performance gains.

关键词： DATA packets & packeting computer algorithms AD hoc networks (computer networks) TELECOMMUNICATION systems WIRELESS communication systems DATA transmission systems

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Design and application of a continuous repetitive controller for rotating mechanisms

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INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES 2000年第9期42卷 1805-1819页

作者： Fung, RF Huang, JS Chien, CG Wang, YC Chung Yuan Christian Univ Dept Mech Engn Chungli 32023 Taiwan Chien Hsin Coll Technol & Commerce Dept Mech Engn Chungli 32023 Taiwan

In this paper the continuous repetitive controller is designed to reject the periodic disturbance and track periodic reference signal for rotating mechanisms. The stability condition is derived and the system is shown to satisfy the internal model principle, which assures that the control output tracks a class of reference commands without a steady-state error if the generator for the references is included in the stable closed-loop system. In order to satisfy this principle, a periodic signal generator is placed in the feedback loop to reject periodic disturbances and to track repetitive reference signals. The best control method will be chosen from the viewpoint of suitability in the practical problems. Finally, the repetitive control algorithm is applied to both the slider-crank and quick-return mechanisms. (C) 2000 Elsevier Science Ltd. All rights reserved.

关键词： Repetitive controllers steady-state error Reference signals periodic disturbance slider crank Closed loop systems Control Methods computer algorithms Comment Periodic Internal model principle Steady state Signal generators

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A theoretical comparison of LRU and LRU-K

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ACTA INFORMATICA 2010年第7-8期47卷 359-374页

作者： Boyar, Joan Ehmsen, Martin R. Kohrt, Jens S. Larsen, Kim S. Univ So Denmark Dept Math & Comp Sci DK-5230 Odense M Denmark

The paging algorithm Least Recently Used Second Last Request (LRU-2) was proposed for use in database disk buffering and shown experimentally to perform better than Least Recently Used (LRU). We compare LRU-2 and LRU theoretically, using both the standard competitive analysis and the newer relative worst order analysis. The competitive ratio for LRU-2 is shown to be 2k for cache size k, which is worse than LRU's competitive ratio of k. However, using relative worst order analysis, we show that LRU-2 and LRU are comparable in LRU-2's favor, giving a theoretical justification for the experimental results. Many of our results for LRU-2 also apply to its generalization, Least Recently Used Kth Last Request.

关键词： computer algorithms EXPERIMENTAL design LEAST squares BUFFER storage (computer science) DATABASES STANDARD deviations

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Coupling Response Surface and Differential Evolution for Parameter Identification Problems

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computer-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING 2015年第5期30卷 376-393页

作者： Vincenzi, Loris Savoia, Marco DIEF Univ Modena & Reggio Emilia I-41125 Modena Italy Univ Bologna DICAM I-40136 Bologna Italy

In the present article, a new surrogate-assisted evolutionary algorithm for dynamic identification problems with unknown parameters is presented. It is based on the combination of the response surface (RS) approach (the surrogate model) with differential evolution algorithm for global search. Differential evolution (DE) is an evolutionary algorithm where N different vectors collecting the parameters of the system are chosen randomly or by adding weighted differences between vectors obtained from two populations. In the proposed algorithm (called DE-Q), the RS is introduced in the mutation operation. The new parameter vector is defined as the one minimizing the second-order polynomial function (RS), approximating the objective function. The performances in terms of speed rate are improved by introducing the second-order approximation;nevertheless, robustness of DE algorithm for global minimum search of objective function is preserved, because multiple search points are used simultaneously. Numerical examples are presented, concerning: search of the global minimum of analytical benchmark functions;parameter identification of a damaged beam;parameter identification of mechanical properties (masses and member stiffnesses) of a truss-girder steel bridge starting from frequencies and eigenvectors obtained from an experimental field test.

关键词： EVOLUTIONARY algorithms DIFFERENTIAL evolution (computer science) RESPONSE surfaces (Statistics) computer algorithms MECHANICAL behavior of materials STIFFNESS (Mechanics)

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Protocol converter synthesis

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IEE PROCEEDINGS-computerS AND DIGITAL TECHNIQUES 2004年第6期151卷 391-401页

作者： Androutsopoulos, V Brookes, DM Clarke, TJW Univ London Imperial Coll Sci Technol & Med Dept Elect & Elect Engn London SW7 2BT England

A system-on-a-chip is an interconnection of different pre-verified IP hardware blocks, which communicate using complex protocols. The integration of IP blocks requires some glue logic to interface otherwise incompatible datapaths. This glue logic is called a protocol converter and its manual design proves to be a tedious and time-consuming task. Automatic synthesis is therefore important, but for optimal system-level design it is necessary to consider not just the correctness, but also the quality (in terms of bandwidth and latency of data transfer) of the converter. A good solution to this problem will allow greater use of protocol-level abstraction as a design tool in system design and synthesis. Results are presented on automatic synthesis of a converter between two protocols. It is shown how converter logic which is bandwidth-optimal can be synthesised for datapaths with an arbitrary number of data ports each of which has arbitrary-size first-in first-out (FIFO) storage. An extension of the product FSM converter synthesis algorithm to include FIFO data-paths is presented. In addition the converter bandwidth is identified as a mean cycle graph problem which is solved using maximum mean cycle graph algorithms.

关键词： computer network protocols computer networks STANDARDS computer input-output equipment computer network architectures DATA transmission systems GRAPH algorithms computer algorithms

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A robust tuning procedure for adaptive inferential control

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INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING 1999年第2期13卷 85-103页

作者： Brodie, KA Tham, MT Willis, MJ Univ Newcastle Upon Tyne Dept Chem & Proc Engn Adv Proc Control Grp Newcastle Upon Tyne NE1 7RU Tyne & Wear England

Inferential estimation and control are techniques tailored for processes with severe sampling limitations on key process measurements. Often such systems have complex, time-varying dynamics making sustainable control performance an elusive target. As potential solutions, adaptive and robust control have been suggested with varying degrees of success. In this work, robust control principles are used to develop a tuning procedure for an adaptive inferential control algorithm, in order to monitor and optimize control performance. The primary advantage of the technique is that performance-robustness targets are maintained despite changes in system dynamics. A case study is used to demonstrate the utility of the technique highlighting the performance enhancements provided by the combination of adaptive and robust inferential control. Copyright (C) 1999 John Wiley & Sons, Ltd.

关键词： tuning WWOX gene control performance Robust control enhancing performance computer algorithms Self tuning

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Recent theoretical progress in understanding coherent structures in edge and SOL turbulence

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JOURNAL OF PLASMA PHYSICS 2008年第5期74卷 679-717页

作者： Krasheninnikov, S. I. D'Ippolito, D. A. Myra, J. R. Univ Calif San Diego San Diego CA 92103 USA Lodestar Res Corp Boulder CO USA

In this paper we review some theoretical aspects of the dynamics of the mesoscale filaments extending along the magnetic field lines in the edge plasma, which are often called 'blobs'. We start with a brief historical survey of experimental data and the main ideas on edge and SOL plasma transport, which finally evolved into the modern paradigm of convective very-intermittent cross-field edge plasma transport. We show that both extensive analytic treatments and numerical simulations demonstrate that plasma blobs with enhanced pressure can be convected coherently towards the wall. The mechanism of convection is related to an effective gravity force (e.g. owing to magnetic curvature effects), which causes plasma polarization and a corresponding E x B convection. The impacts of different effects (e.g. X-point magnetic geometry, plasma collisionality, plasma beta, etc.) on blob dynamics are considered. Theory and simulation predict, both for current tokamaks and for ITER, blob propagation speeds and cross-field sizes to be of the order of a few hundred meters per second and a centimeter, respectively, which are in reasonable agreement with available experimental data. Moreover, the concept of blobs as a fundamental entity of convective transport in the scrape-off layer provides explanations for observed outwards convective transport, intermittency and non-Gaussian statistics in edge plasmas, and enhanced wall recycling in both toroidal and linear machines.

关键词： PLASMA turbulence MAGNETIC fields RESEARCH DIMENSIONAL analysis computer algorithms SIMULATION methods & models ANALYTICAL mechanics

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