电网设备状态检测真型实验平台的设计与实现

针对电网设备状态检测技术推广应用过程中,面临的抗干扰技术研究、仪器性能检测与比对、技术培训、新技术研究等工作缺乏真型设备实验平台的问题,对状态检测特别是带电检测技术的研究应用现状及面临的问题进行了分析,提出了电网设备状态检测实验平台的设计方案。利用110 k V GIS、变压器、电缆及10 k V开关柜、箱变等真型设备,在机械结构、绝缘性能、内置传感器优化布局、典型缺陷设置等方面进行了改造,研制了变压器、GIS内置特高频局放传感器、高压电缆内置电容型高频局放传感器,并建立了基于真型电网设备状态检测的实验平台。在该平台上对变压器、GIS、高压电缆、配电设备的典型局部放缺陷进行了同步模拟与检测实验。结果表明:该平台能够完成电网设备状态检测技术的研究开发、技能培训、仪器校验与比对等工作,能够真实模拟变电站运行工况、复杂电磁环境下各种输变配设备典型缺陷,对推动状态检测技术的研究与应用具有重要的实际意义。

GIS状态监测实验平台建设及状态检测技术研究

SF6气体绝缘变电站(GIS)的状态监测技术在电力系统中得到越来越广泛的应用,并取得了显著成效。笔者研制了内置式UHF局放传感器及宽带信号放大器,利用退出运行的126 k V GIS设备,设计和建立了GIS状态监测实验平台,设置了内置传感器和典型绝缘缺陷;研究了尖端和悬浮间隙两种典型缺陷局部放电信号的时域、频域及PRPS谱图的典型特征。应用该平台能够完成GIS设备状态监测技术的研究开发、技能培训、仪器校验与比对等工作,能够真实模拟变电站运行工况、复杂电磁环境下各种设备典型缺陷,对推动状态监测技术的研究与应用具有重要的实际意义。

GIS状态监测实验平台建设及状态监测研究

SF6气体绝缘变电站(GIS)的状态监测技术在电力系统中得到越来越广泛的应用,并取得了显著成效。首先研制了内置式UHF局放传感器及宽带信号放大器并进行相应测试。然后,利用退出运行的126 kV GIS设备,在机械结构、绝缘性能、内置传感器布局和典型缺陷设置等方面进行了设计改进,建设完成了状态监测实验平台,并得到了两种典型缺陷局部放电信号的时域、频域及PRPS谱图的典型特征。应用该平台能够完成GIS设备状态监测技术的研究开发、技能培训、仪器校验与比对等工作,能够真实模拟变电站运行工况、复杂电磁环境下各种设备典型缺陷,对推动状态监测技术的研究与应用具有重要的实际意义。

Simulation of Spread of Infectious Diseases and Population Mobility in a Deterministic Epidemic Patch Model

Computer simulation models are widely applied in various areas of the health care sector, including the spread of infectious diseases. Patch models involve explicit movements of people between distinct locations. The aim of the present work has been designed and explored a patch model with population mobility between different patches and between each patch and an external population. The authors considered a SIR （susceptible-infected-recovered） scheme. The model was explored by computer simulations. The results show how endemic levels are reached in all patches of the system. Furthermore, the performed explorations suggest that the people mobility between patches, the immigration from outside the system and the infection rate in each patch, are factors that may influence the dynamics of epidemics and should be considered in health policy planning.

A general simulation model developing process based on five-object framework

Different paradigms that relate verification and validation to the simulation model have different development process. A simulation model developing process based on Five-Object Framework (FOF) is discussed in this paper. An example is given to demonstrate the applications of the proposed method.

Analysis of Smoke Distribution in the Subway Station with Various Main Tunnel Ventilations

Fire-driven flow analysis in the underground subway station has been performed with various main tunnel ventilations. Shin-gum-ho station （depth： 46 m） in Seoul is selected as a simulation model. The ventilation mode is assumed to be emergency state. Various main tunnel ventilations are applied to operate in a proper way for helping of smoke exhaustion in platform. The entire station is covered for simulation. Ventilation diffusers are modeled as 95 square shapes of 0.6 m × 0.6 m in the lobby and as 222 square shapes of 0.6 m × 0.6 m and four rectangular shapes of 1.2 m × 0.8 m in the platform. The total of 7.5 million grids is generated and whole domain is divided to 22 blocks for MPI （massage passing interface） efficiency of calculation. LES （large eddy simulation） is applied to solve the momentum equation. Smagorinsky model （Cs = 0.2） is used as SGS （subgrid scale） model. The distribution of CO （carbon monoxide） is calculated for various capacity of main tunnel ventilation and compared with each other.

Numerical simulation of the filling stage in injection molding based on a 3D model

Most injection molded parts are three-dimensional, with complex geometrical configurations and thick/thin wall sections. The change of the thickness of parts has significant influence on flow during injection molding. This paper presents a 3D finite element model to deal with the three-dimensional flow, which can more accurately predict the filling process than a 2.5D model. In this model, equal-order velocity-pressure interpolation method is successfully employed and the relation between velocity and pressure is obtained from the discretized momentum equation in order to derive the pressure equation. A 3D control volume scheme is employed to track the flow front. The validity of the model has been tested through the analysis of the flow in a cavity.

Construction Method of 3D Aorta Model

With the help of engineering technologies, there are varieties of medical supports such as surgical simulations, preoperative plans, intraoperative supports, and diagnostic explanations. In order to perform preoperative plans, the simulation model of the target organ is necessary, and is usually generated from some fine images obtained by imaging devices such as CT （computed tomography） or MRI （magnetic resonance imaging）. These devices, however, are very large and it is difficult to use them during the surgery although there is a kind of MRI that can be used during operations. On the other hand, there is a device called Ultrasonography （US Echo）. It is so handy and can be easily used during operations without radiation or magnetic effect. US images, however, are not usually used for the construction of 3D model for preoperative plans since there are so many noises in the image, and the quality of the image is not so good compared to the images obtained by CT or MRI. Therefore, the authors have tried to construct 3D volumetric shape model from just two 2D US （ultrasound） images, which are the horizontal and vertical cross-section images of the target organ. Their concrete target organ and surgery are the aorta and AAE （annuloaortic ectasia）, respectively. With some technologies of image processing, the boundary of the aorta is extracted for both cross-section images, and the thickness of the aorta is estimated. These processes are applied to not only the aorta wall but also the aorta valve. Finally, the aorta shape model can be constructed by inserting the estimated horizontal aorta images into the estimated vertical one. The constructed model has three dimensions so that it can be viewed from any point of view.

Design and Simulation of IEC 62056 Electricity Meter Model

This paper gives a brief introduction of IEC 62056 standards at first and then discusses the details about how to build the meter function model and the data model according to IEC 62056 standards.Finally it is described how to realize the IEC 62056 electricity meter by a simulation instance.

Analysis and Design of Flexible Pavements by Empirical Tools

This paper falls into two parts. In the first part, the widely used analytical-empirical method of pavement design and evaluation is discussed and in the second part two simulation models are presented to predict the design of flexible pavement. Analytical results are compared with simulation models.

Microscopic Fuzzy Urban Traffic Simulation with Variable Demand

Some microscopic traffic simulations on urban road network are developed up to now. However, the effect of urban transport policy in the local city is influenced with the complex interaction of automobile traffic and public transport traffic. Particularly, behaviours of vehicles should be described with the fuzziness of the subjective recognition and operation. On the other hand, the trip makers are influenced by various transport policies in terms of mode choice behaviour. The change in mode choice behaviour and number of public transport mode users would eventually affect traffic flow conditions on road network. Modal spilt and traffic conditions of a network are interrelated. Therefore, the present study mainly aims to integrate mode choice model and microscopic traffic simulation model based on fuzzy logic. In the study, the fuzzy logic based mode choice model is proposed. The proposed mode choice model and the existing microscopic traffic simulation model are combined. The developed model has been applied on real urban network to demonstrate the effectiveness of the installation of LRT system. Finally, it is helpful for evaluation of transport policy that the fuzzy logic based microscopic traffic simulation with modal choice model has been constructed.

Analysis of Hydrological Simulation Models Using the Parameter Combinatorial Diagram

The aim of this paper is to present graphically the behaviour of a simulation model to the varying parameters and to establish the suitability of this representation as a valid tool for the analysis of the same parameters. In this paper, we define parameter combinatorial diagram as the joint graphical representation of all box plots related to the adjustment between real and simulated data, by setting and/or changing the parameters of the simulation model. To do this, we start with a box plot representing the values of an objective adjustment function, achieving these results when varying all the parameters of the simulation model, Then we draw the box plot when setting all the parameters of the model, for example, using the median or average. Later, we get all the box plots when carrying out simulations combining fixed or variable values of the model parameters. Finally, all box plots obtained are represented neatly in a single graph. It is intended that the new parameter combinatorial diagram is used to examine and analyze simulation models useful in practice. This paper presents combinatorial diagrams of different examples of application as in the case of hydrologic models of one, two, three, and five parameters.

Calibration of a Microscopic Model of an Urban Traffic Network

Traffic simulation models have the potential to provide an objective, cost-effective and flexible approach to assessing system design, traffic operations and management strategies. In that regard, the calibration and validation of simulation model is crucial for appropriate decision making process. This paper presents an application of microscopic simulation model calibration and validation procedure for a multimodal urban traffic network. Model is developed by VISSIM and VISSIG software tools.

Simulating the Effect of Propylene Promoter on Product Yield with FCC Mechanism Model

A FCC mechanism model was used to predict the effects of propylene promoter in a 3.0 Mt/a FCCU. The FCC mechanism model was developed based on one set of commercial FCC data without using the promoter, and was modified by using another set of commercial FCC data with 3m% promoter in the catalyst inventory, and the calculations by means of this simulation model were performed to predict the data of the FCC unit containing 4m% promoter in the catalyst inventory. The test results showed that the calculated values agreed well with the data obtained from the commercial FCC unit, in which the deviations of calculated product yields versus the actual product yields at the commercial FCC unit were equal to 1.74 percentage points for gasoline, 2.59 percentage points for diesel, 1.50 percentage points for dry gas and LPG, and 0.28 percentage points for coke. The proposed method regarding the development of a simulation model and modifications to the model for commercial FCC unit was feasible.

AUV Modeling and Motion Control Strategy Design

To provide a suitable model for AUV simulation and control purposes, a general nonlinear dynamic model including a novel thruster hydrodynamics model was derived. Based on the modeling method, the "AUV-XX" simulation platform was established to carry out fundamental tests on its motion characteristics, stability, and controllability. A motion control strategy consisting of both position and speed control in a horizontal plane was designed for different task assignments of underwater vehicles. Combined control of heave and pitch was adopted to compensate for the reduction of vertical tunnel thrusters when the vehicle is moving at a high speed. An improved S-surface controller based on the capacitor plate model was developed with flexible gain selections made possible by different forms of restricting the error and changing the rate of the error. Simulation results show that the derived general mathematical model together with simulation platform can provide a test bed for fundamental tests of motion control. Additionally, the capacitor plate model S-surface control shows a good performance in guiding the vehicle to achieve the desired position and speed with sufficient accuracy.

Cardinal temperatures and required biological days from sowing to emergence of three millet species （common, foxtail, pearl millet）

The modeling of germination and seedling emergence is required for the construction of a simulation model of three species of millet （panicum miliaceum, pennisetum galucum and setaria italica）. This study provides the necessary temperature parameters to model these processes. For this purpose, different non-linear regression models including fiat, logistic, quadratic, sigmoidal, dent-like, segmented, beta and curvilinear were used. Root Mean Square of Errors, coefficient of determination and regression coefficients of predicted values versus observed were used to find the appropriate model. Investigating regression coefficients indicated that dent-like model has the least RMSE and a coefficient （RMSE=0.000009, a=0.0006） and the biggest R2 and b coefficient （R2=0.96, b=0.98） in common millet. These coefficients were （RMSE=0.01, a=0.005） and （R2=0.94, b=0.97）, and （RMSE=0.004, a=0.05） and （R2=0.99, b=0.99）, for beta in foxtail and pearl millet, respectively. According to these coefficients, dent-like, was chosen as the best model to describe the response of common millet germination to temperature （Tb=7~C and Tc=49.50℃）. Also beta, was chosen for foxtail millet （Tb=7℃, Tc=49.50℃）. Beta, was chosen as the best model for pearl millet （Tb=6.5 ℃ and To=4 ℃ ）. These parameters can be used in millet simulation models to predict sowing to emergence duration based on a thermal time concept. Also, required biological days from sowing to emergence using these models varied from 3.57, 4.29 and 5.54, for common millet, foxtail millet and pearl millet, respectively.

Simulation Model for Photosynthetic Production in Oilseed Rape

Photosynthetic production is a major determinant of final yield in crop plants. A simulation model was developed for canopy photosynthesis and dry matter accumulation in oilseed rape (Brassica napus L.) based on the ecophysiological processes and using a three-layer radiation balance scheme for calculating the radiation interception and absorption by the layers of flowers, pods, and leaves within the canopy. Gaussian integration method was used to calculate photosynthesis of the pod and leaf layers, and the daily total canopy photosynthesis was determined by the sum of photosynthesis from the two layers of green organs. The effects of physiological age, temperature, nitrogen, and water deficit on maximum photosynthetic rate were quantified. Maintenance and growth respiration were estimated to determine net photosynthetic production. Partition index of the shoot in relation to physiological development time was used to calculate shoot dry matter from plant biomass and shoot biomass loss because of freezing was quantified by temperature effectiveness. Testing of the model for dynamic dry matter accumulation through field experiments of different genotypes, sowing dates, and nitrogen levels showed good fit between the observed and simulated data, with an average root mean square error of 10.9% for shoot dry matter. Thus, the present model appears to be reliable for the prediction of photosynthetic production in oilseed rape.

Effect of discounting on estimation of benefits determined by hepatitis C treatment

The combination of either boceprevir or telaprevir with ribavirin and interferon (triple therapy) has been shown to be more effective than ribavirin+interferon (dual therapy) for the treatment of genotype 1 hepatitis C. Since the benefit of these treatments takes place after years, simulation models are needed to predict long-term outcomes. In simulation models, the choice of different values of yearly discount rates (e.g., 6%, 3.5%, 2%, 1.5% or 0%) influences the results, but no studies have specifically addressed this issue. We examined this point by determining the long-term benefits under different conditions on the basis of standard modelling and using quality-adjusted life years (QALYs) to quantify the benefits. In our base case scenario, we compared the long-term benefit between patients given a treatment with a 40% sustained virologic response (SVR) (dual therapy) and patients given a treatment with a 70% SVR (triple therapy), and we then examined how these specific yearly discount rates influenced the incremental benefit. The gain between a 70% SVR and a 40% SVR decreased from 0.45 QA-LYs with a 0% discount rate to 0.22 QALYs with a 6% discount rate (ratio between the two values = 2.04).Testing the other discounting assumptions confirmed that the discount rate has a marked impact on the magnitude of the model-estimated incremental benefit. In conclusion, the results of our analysis can be helpful to better interpret cost-effectiveness studies evaluating new treatment for hepatitis C.

Micro-motion effect in inverse synthetic aperture radar imaging of ballistic mid-course targets

For ballistic mid-course targets,in addition to constant orbital motion,the target or any structure on the target undergoes micro-motion dynamics,such as spin,precession and tumbling.The micro-motion characteristics of the ballistic mid-course targets were discussed.The target motion model and inverse synthetic aperture radar(ISAR) imaging model for this kind of targets were built.Then,the influence of micro-motion on ISAR imaging based on the established imaging model was presented.The computer simulation to get mid-course target echoes from static darkroom electromagnetic scattering data based on the established target motion model was realized.The imaging results of computer simulation show the validity of ISAR imaging analysis for micro-motion targets.

Study on the Crustal Velocity Model of Xinjiang and Its Subareas

In this paper,we firstly analyze the "3,400 travel time table "used for a long time in Xinjiang Seismological Network to obtain the velocity structure models in accord with the table by fitting. Then we fit the velocity of all seismic phases recorded in Xinjiang region in January 2009 ~ December 2013. Simulation analysis is done on the reliability and stability of the velocities,and a concept is proposed for building subarea crustal velocity models according to partitioning of seismic cluster regions. The crustal velocity model suitable for the Yutian area is fitted with the data of all phases of seismic events within a radius of 1°around the 2014 Yutian M_S7.3 earthquake since January 2009,and the model is applied to the relocation of the Yutian M_S7.3 earthquake and determination of focal depths of the earthquake sequence.