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Research on Optimal Inspection Strategy for Overhead Transmission Line Based on Smart Grid

Procedia Computer Science 2018年 130卷 1134-1139页

作者： Liu Jian Gao Feng Zhao Ming Chen Liuning Li Weiyao School of Electrical Engineering Wuhan university Wuhan 430072 China State Grid Zhengzhou Power Supply Company Henan 450052 China State Grid Nanyang Power Supply Company Henan 473005 China

Due to the urgent demand for the monitoring of overhead transmission lines in smart grid, this paper proposes an optimal inspection strategy for overhead transmission line considering time-varying failure rate. Based on the goal benefit function of inspection cost, failure electric cost and the maintaining reliability cost, modal of the inspection strategy is established with genetic algorithm. The reliability index could contribute to a dynamic and variable inspection cycle of transmission line via genetic algorithm. According to the calculation results of the middle area of China, it is presented that the algorithm can work out inspection strategy according to the actual failure rate, and get a rational and economical, regional, seasonal, dynamic inspection cycle plan. Thus, it can avoid the traditional over-inspection and lack-inspection problems. The state of transmission line can be guaranteed in more economical way, satisfying the demand of real-time capability and reliability

关键词： smart grid overhead transmission line inspection strategy time-varying failure rate monte-carlo algorithm

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High performance modelling of the transport of energetic particles for photon radiotherapy

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PHYSICA MEDICA-EUROPEAN JOURNAL OF MEDICAL PHYSICS 2017年 42卷 305-312页

作者： Birindelli, Gabriele Feugeas, Jean-Luc Caron, Jerome Dubroca, Bruno Kantor, Guy Page, Jonathan Pichard, Teddy Tikhonchuk, Vladimir Nicolai, Philippe Univ Bordeaux CNRS CEA CELIACtr Laser Intenses & Applicat F-33400 Talence France Inst Bergonie Comprehens Canc Ctr Dept Radiotherapy F-33076 Bordeaux France

This work consists of the validation of a new Grid Based Boltzmann Solver (GBBS) conceived for the description of the transport and energy deposition by energetic particles for radiotherapy purposes. The entropic closure and a compact mathematical formulation allow our code (M1) to calculate the delivered dose with an accuracy comparable to the monte-carlo (MC) codes with a computational time that is reduced to the order of few minutes without any special processing power requirement. A validation protocol with heterogeneity inserts has been defined for different photon sources. The comparison with the MC calculated depth-dose curves and transverse profiles of the beam at different depths shows an excellent accuracy of the M1 model. (C) 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

关键词： Radiotherapy treatment planning system Deterministic dose calculation monte-carlo algorithm Boltzmann equation

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Comparison of Pencil-beam, Collapsed-cone and monte-carlo algorithms in Radiotherapy Treatment Planning for 6-MV photons

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JOURNAL OF THE KOREAN PHYSICAL SOCIETY 2015年第1期67卷 153-158页

作者： Kim, Sung Jin Kim, Sung Kyu Kim, Dong Ho Yeungnam Univ Dept Phys Gyongsan 712749 South Korea Eulji Univ Hosp Dept Radiat Oncol Daejeon 302799 South Korea Yeungnam Univ Dept Radiat Oncol Coll Med Taegu 705717 South Korea

Treatment planning system calculations in inhomogeneous regions may present significant inaccuracies due to loss of electronic equilibrium. In this study, three different dose calculation algorithms, pencil beam (PB), collapsed cone (CC), and monte-carlo (MC), provided by our planning system were compared to assess their impact on the three-dimensional planning of lung and breast cases. A total of five breast and five lung cases were calculated by using the PB, CC, and MC algorithms. Planning treatment volume (PTV) and organs at risk (OARs) delineations were performed according to our institution's protocols on the Oncentra MasterPlan image registration module, on 0.3 - 0.5 cm computed tomography (CT) slices taken under normal respiration conditions. Intensity-modulated radiation therapy (IMRT) plans were calculated for the three algorithm for each patient. The plans were conducted on the Oncentra MasterPlan (PB and CC) and CMS Monaco (MC) treatment planning systems for 6 MV. The plans were compared in terms of the dose distribution in target, the OAR volumes, and the monitor units (MUs). Furthermore, absolute dosimetry was measured using a three-dimensional diode array detector (ArcCHECK) to evaluate the dose differences in a homogeneous phantom. Comparing the dose distributions planned by using the PB, CC, and MC algorithms, the PB algorithm provided adequate coverage of the PTV. The MUs calculated using the PB algorithm were less than those calculated by using. The MC algorithm showed the highest accuracy in terms of the absolute dosimetry. Differences were found when comparing the calculation algorithms. The PB algorithm estimated higher doses for the target than the CC and the MC algorithms. The PB algorithm actually overestimated the dose compared with those calculated by using the CC and the MC algorithms. The MC algorithm showed better accuracy than the other algorithms.

关键词： Dose calculation algorithm Collapsed cone algorithm monte-carlo algorithm

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Research on Series-connected Augmented Railgun Inductance Gradient and Its Influencing parameters

Research on Series-connected Augmented Railgun Inductance Gr...

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2015 4th International Conference on Computer, Mechatronics, Control and Electronic Engineering (ICCMCEE 2015)

作者： WAN Min WANG Zhiheng LI Xiaojiang The Academy of Equipment

ISBN: (纸本)9781510813465

The inductance gradient is one of the most important indexes to evaluate the performance of the electromagnetic railgun. It has important theoretical and practical value to research the inductance gradient and its influencing parameters. According to the Biot-Savat's law and the principle of virtual work, the expression of the inductance gradient considered the skin effect of current has been given, and by using monte-carlo algorithm the numerical solution has been calculated. In order to verify the correctness and accuracy of the model, the finite element simulation software is used to compare with the numerical solution. Based on the model, the influencing parameters of inductance gradient has been analyzed, and the variation of the inductance gradient has been summarized. The results show that, the inductance gradient decrease with the separation distance between the inside and outside rail, decrease with the height and width of the rail, increase with the displacement of the armature then tend to constant. The research can provide a reference for the design of series-connected augmented railgun.

关键词： Series-connected Augmented railgun inductance gradient monte-carlo algorithm finite element simulation influencing parameters

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Construction and Analysis of Lattice Boltzmann Methods Applied to a 1D Convection-Diffusion Equation

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ACTA APPLICANDAE MATHEMATICAE 2014年第1期131卷 69-140页

作者： Dellacherie, Stephane CEA Commissariat Energie Atom & Energies Alternat DEN STMFDM2S F-91191 Gif Sur Yvette France

To solve the 1D (linear) convection-diffusion equation, we construct and we analyze two LBM schemes built on the D1Q2 lattice. We obtain these LBM schemes by showing that the 1D convection-diffusion equation is the fluid limit of a discrete velocity kinetic system. Then, we show in the periodic case that these LBM schemes are equivalent to a finite difference type scheme named LFCCDF scheme. This allows us, firstly, to prove the convergence in L (a) of these schemes, and to obtain discrete maximum principles for any time step in the case of the 1D diffusion equation with different boundary conditions. Secondly, this allows us to obtain most of these results for the Du Fort-Frankel scheme for a particular choice of the first iterate. We also underline that these LBM schemes can be applied to the (linear) advection equation and we obtain a stability result in L (a) under a classical CFL condition. Moreover, by proposing a probabilistic interpretation of these LBM schemes, we also obtain monte-carlo algorithms which approach the 1D (linear) diffusion equation. At last, we present numerical applications justifying these results.

关键词： Convection-diffusion equation Lattice Boltzmann method D1Q2 lattice Chapman-Enskog expansion Hilbert expansion LFCCDF scheme Du Fort-Frankel scheme Stability and convergence in L-infinity Discrete maximum principle monte-carlo algorithm

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Appearance-based approach to hybrid metric-topological simultaneous localisation and mapping

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IET INTELLIGENT TRANSPORT SYSTEMS 2014年第8期8卷 688-699页

作者： Fernandez, Lorenzo Paya, Luis Reinoso, Oscar Miguel Jimenez, Luis Univ Miguel Hernandez Dept Ingn Sistemas Ind Alicante Spain

In this study a unified framework to carry out the simultaneous localisation and mapping of a mobile robot combining metric and topological techniques is presented. The robot moves in a real indoor environment and the algorithm makes use of the information provided by an omnidirectional camera mounted on the robot and its internal odometry. The hybrid approach consists in constructing simultaneously two maps of the environment, one metric and other topological with relationships between them which are updated in each step. The robot goes through the environment to build up a map while continuously captures images. To build the topological map the most relevant information from the scenes is extracted using a global appearance descriptor. A new node is added to the map when the appearance between two images is sufficiently different. Also, the authors check if there is a loop closure with a previous node. At the same time, a metrical map of the environment is computed. With this aim, the authors estimate the position of the robot when it captures a new image using a monte-carlo algorithm. The authors show how it is possible to obtain a reasonable performance both in time and accuracy in an indoor environment, when the involved parameters are properly tuned.

关键词： SLAM (robots) robot vision mobile robots feature extraction monte carlo methods cameras appearance-based approach hybrid metric-topological simultaneous localisation and mapping mobile robot indoor environment omnidirectional camera internal odometry global appearance descriptor scene extraction loop closure monte-carlo algorithm position estimation

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A Fast Radiative Transfer Model for the Meteor-M satellite-based hyperspectral IR sounders

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IZVESTIYA ATMOSPHERIC AND OCEANIC PHYSICS 2014年第9期50卷 968-977页

作者： Uspensky, A. B. Rublev, A. N. Rusin, E. V. Pyatkin, V. P. Planeta State Res Ctr Moscow 123242 Russia Russian Acad Sci Siberian Branch Inst Computat Math & Math Geophys Novosibirsk 630090 Russia

The methodological and computational aspects of Fast Radiative Transfer Model (FRTM) development designed for the analysis and validation of the data of measurements using satellite-based instrument-hyperspectral IR sounders of high spectral resolution-are considered. A description of the FRTM is given for the analysis and modeling of the measurements by the IRFS-2 IR Fourier spectrometer for polarorbiting meteorological satellites of the Meteor-M series based on the known RTTOV FRTM. Computational efficiency is estimated and the results of the verification of developed FRTM are presented. They were obtained from a comparison of model simulations with exact line-by-line calculations for the IRFS-2 IR sounder. The increase in computational performance and the accuracy of the FRTM, caused by the application of the algorithms of the principal components method, are discussed. The construction of radiative models, which use the algorithm of the monte carlo method and are applicable for the analysis and modeling of the data of IR sounders under conditions of cloudiness in the instrument field of view, is considered.

关键词： fast radiative transfer model IR-sounder IRFS-2 remote sensing satellite data modeling RTTOV optical depth Jacobian monte-carlo algorithm

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DEVELOPMENT OF A FUZZY-BASED TIDAL VOLUME algorithm FOR PATIENTS WITH RESPIRATORY DISTRESS

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GA...

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JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY 2014年第4期29卷 699-706页

作者： Guler, Hasan Ata, Fikret Firat Univ Muh Fak Elekt Elekt Munhendisligi Bolumu TR-23169 Elazig Turkey

The purpose of the present study is to develop a fuzzy-based tidal volume algorithm for patients with respiratory distress. The standard of care when ventilating patients with the acute respiratory distress syndrome is to use a tidal volume of 6 ml/kg for ideal body weight. But, this tidal volume aim is frequently exceeded for many reasons, most typically related to physician discomfort with clinical parameters of inadequate oxygenation and ventilation. Thus, an algorithm based on fuzzy logic has been developed in Matlab to prevent deviation in tidal volume. The inputs of fuzzy were positive end-expiratory pressure (PEEP), plateau pressure (Pplt) and arterial oxygen saturation (SaO(2)) and the change of PEEP. Random clinical scenarios were generated via using monte-carlo simulation and Gaussian distribution methods. The student t-test for p <0.05 was used to compare the obtained results from simulations and clinicians' decision. It was found that there is no statistical discrepancy in the value of tidal volume. It can be said that this algorithm may prove useful as means of rationalizing and standardizing departures from desired 6 ml/kg tidal volume in any given patient.

关键词： Fuzzy Logic Mechanical Ventilation monte-carlo algorithm Gaussian Distribution

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Safeguard management for operation security in nuclear power plants (NPPs)

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ANNALS OF NUCLEAR ENERGY 2011年第2-3期38卷 167-174页

作者： Woo, Tae-Ho Lee, Un-Chul Seoul Natl Univ Dept Nucl Engn Seoul 151742 South Korea

Safeguard modeling is conducted for the successful operations in the nuclear power plants (NPPs). The characteristics of the secure operation in NPPs are investigated using the network effect method which is quantified by the monte-carlo algorithm. Fundamentally, it is impossible to predict the exact time of a terror incident. So, the random sampling for the event frequency is a reasonable method, including the characteristics of network effect method such as the zero-sum quantification. The performance of operation with safeguard is the major concern of this study. There are three kinds of considerations as the neutronics, thermo-hydraulics, and safeguard properties which are organized as an aspect of safeguard considerations. The result, therefore, can give the stability of the operations when the power is decided. The maximum value of secure operation is 12.0 in the third month and the minimum value is 1.0 in the 18th and 54th months, in a 10 years period. Thus, the stability of the secure power operation increases 12 times higher than the lowest value according to this study. This means that the secure operation is changeable in the designed NPPs and the dynamical situation of the secure operation can be shown to the operator. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Nuclear power plants Safeguard Power uprate Network effect monte-carlo algorithm

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On the randomized solution of initial value problems

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JOURNAL OF COMPLEXITY 2011年第3-4期27卷 300-311页

作者： Daun, Thomas Univ Kaiserslautern Dept Comp Sci D-67653 Kaiserslautern Germany

We study the randomized solution of initial value problems for systems of ordinary differential equations y' (x) = f (x, y(x)), x is an element of [a, b], y(a) =y(0) is an element of R(d). Recently Heinrich and Milla (2008) [4] presented an order optimal randomized algorithm solving this problem for gamma-smooth input data (i.e. gamma = r + rho: the r-th derivatives off satisfy a rho-Holder condition). This algorithm uses function values and values of derivatives of f. In this paper we present an order optimal randomized algorithm for the class of gamma-smooth functions that uses only values off. For this purpose we show how to obtain an order optimal randomized algorithm from an order (sub)optimal deterministic one. (C) 2010 Elsevier Inc. All rights reserved.

关键词： Initial value problem Ordinary differential equation monte-carlo algorithm Complexity

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