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Combined Method of Datum Transformation Between Different Coordinate Systems 被引量:4
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2002年第4期5-9,共5页
The similarity transformation model between different coordinate systems is not accurate enough to describe the discrepancy of them.Therefore,the coordinate transformation from the coordinate frame with poor accuracy ... The similarity transformation model between different coordinate systems is not accurate enough to describe the discrepancy of them.Therefore,the coordinate transformation from the coordinate frame with poor accuracy to that with high accuracy cannot guarantee a high precision of transformation.In this paper,a combined method of similarity transformation and regressive approximating is presented.The local error accumulation and distortion are taken into consideration and the precision of coordinate system is improved by using the recommended method 展开更多
关键词 coordinate transformation similarity transformation regressive approximating
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Hawking effect and quantum nonthermal radiation of an arbitrarily accelerating charged black hole using a new tortoise coordinate transformation 被引量:1
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作者 潘伟珍 杨学军 谢志堃 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期586-591,共6页
Using a new tortoise coordinate transformation, this paper investigates the Hawking effect from an arbitrarily accelerating charged black hole by the improved Damour-Ruffini method. After the tortoise coordinate trans... Using a new tortoise coordinate transformation, this paper investigates the Hawking effect from an arbitrarily accelerating charged black hole by the improved Damour-Ruffini method. After the tortoise coordinate transformation, the Klein-Gordon equation can be written as the standard form at the event horizon. Then extending the outgoing wave from outside to inside of the horizon analytically, the surface gravity and Hawking temperature can be obtained automatically. It is found that the Hawking temperatures of different points on the surface are different. The quantum nonthermal radiation characteristics of a black hole near the event horizon is also discussed by studying the Hamilton-Jacobi equation in curved spacetime and the maximum overlap of the positive and negative energy levels near the event horizon is given. There is a dimensional problem in the standard tortoise coordinate and the present results may be more reasonable. 展开更多
关键词 tortoise coordinate transformation black hole Hawking effect quantum nonthermal radiation
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Grid Model for High-accuracy Coordinate Transformation of China Geodetic Coordinate System 2000 被引量:4
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作者 Zhiping LU Ziqing WEI +1 位作者 Jun LI Chong GUO 《Journal of Geodesy and Geoinformation Science》 2019年第1期17-25,36,共10页
After implementing CGCS2000,establishing grid models for high-accuracy coordinate transformation which are mainly used to transform border lines and coordinate grids of topographic maps becomes an important issue in m... After implementing CGCS2000,establishing grid models for high-accuracy coordinate transformation which are mainly used to transform border lines and coordinate grids of topographic maps becomes an important issue in mapping applications.Consequently,a grid model for high-accuracy coordinate transformation of CGCS2000 is proposed.Specifically,we firstly analyze a minimum curvature equation of coordinate transformation,which possesses the characteristics of both the global and local smoothness,achieving better consistency with the consecutive smoothness for the coordinate transformation of map’s linear feature.Then an iterative calculation method of grid nodes and an approach for establishing regional grid models based on collocation by two-step minimization are proposed.Meanwhile,a data structure of grid model is constructed.Finally we give the optimized grid interval and transformation accuracy in China corresponding to the proposed grid model.Using 48 433 points of 2000 National Geodetic Control Network of China,we take the proposed model into practice by constructing grid models for coordinate transformation from BJS54 and XAS80 to CGCS2000,and the external positional accuracies for both models are 0.26 m and 0.03 m respectively. 展开更多
关键词 CGCS2000 coordinate transformation minimum CURVATURE method grid model data structure COLLOCATION
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Evaluation of the Direct UTM Coordinates Transformation Method Based on the Standard 7-Parameters Transformation 被引量:1
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作者 Mohammed Anwer Jassim Darin Mohammed Tofiq Mohammed 《Journal of Civil Engineering and Architecture》 2022年第8期413-419,共7页
GNSS(global navigation satellite system)observations produce the geodetic position including latitude,longitude,and altitude(or ellipsoidal height)concerning the global reference datum WGS84(Word Geodetic System 1984)... GNSS(global navigation satellite system)observations produce the geodetic position including latitude,longitude,and altitude(or ellipsoidal height)concerning the global reference datum WGS84(Word Geodetic System 1984),which usually should be converted to another local datum to get the desired position meaning in a physical sense,coordinates of points in the local datum are usually calculated by the seven-parameter transformation method.This paper aims to validate the methods of position transformation between WGS84 and the Iraqi local datum Karbala 1979 using the UTM(universal transverse Mercator)projected coordinates directly.The proposed algorithm was tested for 10 ground control points in Erbil city and many selected points in other different cities over all Iraqi territory.The control points are measured by the CHCNAV i73 GNSS receiver.For the evaluation procedure,the RMSE(root mean square error)of the transformed coordinates is calculated with an average value of±10.715 m as an estimated uncertainty of the direct UTM coordinates transformation method over Erbil city territory,and more than±12 m over different places over Iraqi territory. 展开更多
关键词 Direct UTM coordinates transformation global datum WGS84 local Iraqi datum Karbala 1979
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Coordinate Transformation and Exact Solutions of Schrodinger Equation with Position-Dependent Effective Mass
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作者 JU Guo-Xing CAI Chang-Ying +1 位作者 XIANG Yang REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1001-1009,共9页
Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the sy... Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The eigenfunctions can be expressed in terms of the Jacobi, Hermite, and generalized Laguerre polynomials. All potentials for these solvable systems have an extra term Vm, which is produced from the dependence of mass on the position, compared with those for the systems of constant mass. The properties of Vm for several mass functions are discussed. 展开更多
关键词 coordinate transformation Schrodinger equation position-dependent mass EIGENFUNCTION special functions
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Overall Framework and Module of Distribution Network Coordinated Planning Considering Distributed Generation
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作者 Qianjin LIU Huanghuang LIU 《Engineering(科研)》 2013年第1期32-36,共5页
Combining with the characteristics of China's energy and the strategy of sustainable development, analyzing the pros and cons which caused by the appearance of DG and their operation connecting to grid, this paper... Combining with the characteristics of China's energy and the strategy of sustainable development, analyzing the pros and cons which caused by the appearance of DG and their operation connecting to grid, this paper points out that the two sides can achieve win-win under a reasonable combination between DG and distribution system, so as to optimize the allocation of resources, improve the utilization ratio of resource, and obtain maximum social benefit, harmoniously promote the development of power industry, economy and environment. As a word, this paper puts forward a new model of distribution network planning including DG and brings in penalty factorto guide the investment and construction of DG. Last of all, this paper presents the adoption of the coordination development coefficients which is to evaluate the power planning. 展开更多
关键词 distributed generation distribution network PLANNING PENALTY FACTOR coordinateD development COEFFICIENT
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A Study on the Effects of Internal Heat Generation on the Thermal Performance of Solid and Porous Fins using Differential Transformation Method
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作者 M.G.Sobamowo O.A.Adedibu +1 位作者 O.A.Adeleye A.O.Adesina 《Semiconductor Science and Information Devices》 2020年第1期29-36,共8页
In this study,the impacts of internal heat generation on heat transfer enhancement of porous fin is theoretical investigated using differential transform method.The parametric studies reveal that porosity enhances the... In this study,the impacts of internal heat generation on heat transfer enhancement of porous fin is theoretical investigated using differential transform method.The parametric studies reveal that porosity enhances the fin heat dissipating capacity but the internal heat generation decreases the heat enhancement capacity of extended surface.Also,it is established that when the internal heat parameter increases to some certain values,some negative effects are recorded where the fin stores heat rather than dissipating it.This scenario defeats the prime purpose of the cooling fin.Additionally,it is established in the present study that the limiting value of porosity parameter for thermal stability for the passive device increases as internal heat parameter increases.This shows that although the internal heat parameter can help assist higher range and value of thermal stability of the fin,it produces negative effect which greatly defeats the ultimate purpose of the fin.The results in the work will help in fin design for industrial applications where internal heat generation is involved. 展开更多
关键词 Thermal analysis Solid and porous fins Thermal performance Temperature-dependent internal heat generation Differential transformation method
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DISTANCE MEASURING MODELING AND ERROR ANALYSIS OF DUALCCD VISION SYSTEM SIMULATING HUMAN EYES AND NECK 被引量:3
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作者 Wang XuanyinXiao BaopingPan FengState Key Laboratory of Fluid PowerTransmission and Control,Zhejiang University,Hangzhou 310027, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第4期396-399,共4页
A dual-CCD simulating human eyes and neck (DSHEN) vision system is putforward. Its structure and principle are introduced. The DSREN vision system can perform somemovements simulating human eyes and neck by means of f... A dual-CCD simulating human eyes and neck (DSHEN) vision system is putforward. Its structure and principle are introduced. The DSREN vision system can perform somemovements simulating human eyes and neck by means of four rotating joints, and realize preciseobject recognizing and distance measuring in all orientations. The mathematic model of the DSHENvision system is built, and its movement equation is solved. The coordinate error and measureprecision affected by the movement parameters are analyzed by means of intersection measuringmethod. So a theoretic foundation for further research on automatic object recognizing and precisetarget tracking is provided. 展开更多
关键词 Dual-CCD Simulating human eyes and neck (DSHEN) Intersection measure ERRORANALYSIS Homogeneous coordinate transformation
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Review on key technologies and typical applications of multi-station integrated energy systems 被引量:6
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作者 Zhenlan Dou Chunyan Zhang +4 位作者 Wei Wang Dan Wang Qiqi Zhang Yanxing Cai Ruitian Fan 《Global Energy Interconnection》 EI CAS CSCD 2022年第3期309-327,共19页
To realize the low-carbon development of power systems,digital transformation,and power marketization reform,the substation,data center,energy storage,photovoltaic,and charging stations are important components for th... To realize the low-carbon development of power systems,digital transformation,and power marketization reform,the substation,data center,energy storage,photovoltaic,and charging stations are important components for the construction of new infrastructure.The integration infrastructure represented by multi-station integrated energy systems(MSIESs)represents the development trend,and its connotation and denotation are not immutable.This study firstly analyzed the components of MSIESs and their sub-stations and overall characteristics,and proposed an overall architecture for MSIESs.Thereafter,this system was characterized in detail from three aspects:planning and design,operation control,and market operation.The planning and construction of MSIESs was analyzed from the aspects of planning and design process,typical fusion subsystems,supply and demand prediction,and capacity determination;the operational control of MSIESs was analyzed from the aspects of model construction,coordination control,and safety assessment.Moreover,the market operation of MSIESs was examined from the aspects of the business model and spot market.Furthermore,the technical development trend of MSIESs has been explored in this study. 展开更多
关键词 MSIESs New power system Digital transformation Planning and design coordinated control Electricity market
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On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure
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作者 H.ASGHARI L.MILLER +1 位作者 R.PENTA J.MERODIO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第9期1499-1522,共24页
Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid cylinder.We provide a step-by-step guide to obtain the analyt... Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid cylinder.We provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure,stresses,and elastic displacement.We obtain the solution by performing a Laplace transform on the governing equations,which are those of Biot's poroelasticity in cylindrical polar coordinates.We enforce radial boundary conditions and obtain the solution in the Laplace transformed domain before reverting back to the time domain.The sensitivity analysis is then carried out,considering only the derived pressure solution.This analysis finds that the time t,Biot's modulus M,and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P_(0) plays a very little role. 展开更多
关键词 sensitivity analysis Laplace transform cylindrical polar coordinate Biot's modulus CYLINDER
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A complete solution of an improved universal 3D coordinate similarity transformation model 被引量:2
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作者 Leyang Wang Jianqiang Sun Qiwen Wu 《Geodesy and Geodynamics》 CSCD 2021年第2期125-132,共8页
When linearizing three-dimensional(3 D)coordinate similarity transformation model with large rotations,we usually encounter the ill-posed normal matrix which may aggravate the instability of solutions.To alleviate the... When linearizing three-dimensional(3 D)coordinate similarity transformation model with large rotations,we usually encounter the ill-posed normal matrix which may aggravate the instability of solutions.To alleviate the problem,a series of conversions are contributed to the 3 D coordinate similarity transformation model in this paper.We deduced a complete solution for the 3 D coordinate similarity transformation at any rotation with the nonlinear adjustment methodology,which involves the errors of the common and the non-common points.Furthermore,as the large condition number of the normal matrix resulted in an intractable form,we introduced the bary-centralization technique and a surrogate process for deterministic element of the normal matrix,and proved its benefit for alleviating the condition number.The experimental results show that our approach can obtain the smaller condition number to stabilize the convergence of the interested parameters.Especially,our approach can be implemented for considering the errors of the common and the non-common points,thus the accuracy of the transformed coordinates improves. 展开更多
关键词 3D coordinate transformation Nonlinear adjustment Complete solution Condition number Bary-centralization
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Multi-timescale robust dispatching for coordinated automatic generation control and energy storage 被引量:4
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作者 Yiran Ma Xueshan Han +1 位作者 Ming Yang Wei-Jen Lee 《Global Energy Interconnection》 2020年第4期355-364,共10页
The increasing penetration of renewable energy into power grids is reducing the regulation capacity of automatic generation control(AGC).Thus,there is an urgent demand to coordinate AGC units with active equipment suc... The increasing penetration of renewable energy into power grids is reducing the regulation capacity of automatic generation control(AGC).Thus,there is an urgent demand to coordinate AGC units with active equipment such as energy storage.Current dispatch decision-making methods often ignore the intermittent effects of renewable energy.This paper proposes a two-stage robust optimization model in which energy storage is used to compensate for the intermittency of renewable energy for the dispatch of AGC units.This model exploits the rapid adjustment capability of energy storage to compensate for the slow response speed of AGC units,improve the adjustment potential,and respond to the problems of intermittent power generation from renewable energy.A column and constraint generation algorithm is used to solve the model.In an example analysis,the proposed model was more robust than a model that did not consider energy storage at eliminating the effects of intermittency while offering clear improvements in economy and efficiency. 展开更多
关键词 Automatic generation control Energy storage Intermittency coordinated dispatching Robust optimization
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Generalized Birkhofflan representation of nonholonomic systems and its discrete variational algorithm 被引量:3
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作者 刘世兴 刘畅 +1 位作者 花巍 郭永新 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第11期346-352,共7页
By using the discrete variational method,we study the numerical method of the general nonholonomic system in the generalized Birkhoffian framework,and construct a numerical method of generalized Birkhoffian equations ... By using the discrete variational method,we study the numerical method of the general nonholonomic system in the generalized Birkhoffian framework,and construct a numerical method of generalized Birkhoffian equations called a self-adjoint-preserving algorithm.Numerical results show that it is reasonable to study the nonholonomic system by the structure-preserving algorithm in the generalized Birkhoffian framework. 展开更多
关键词 variational preserving coordinates constraints adjoint satisfy manifold transformed preserve symplectic
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Correlation of coordinate transformation parameters 被引量:1
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作者 Du Lan Zhang Hanwei +1 位作者 Zhou Qingyong Wang Ruopu 《Geodesy and Geodynamics》 2012年第1期34-38,共5页
Coordinate transformation parameters between two spatial Cartesian coordinate systems can be solved from the positions of non-colinear corresponding points. Based on the characteristics of translation, rotation and zo... Coordinate transformation parameters between two spatial Cartesian coordinate systems can be solved from the positions of non-colinear corresponding points. Based on the characteristics of translation, rotation and zoom components of the transformation, the complete solution is divided into three steps. Firstly, positional vectors are regulated with respect to the centroid of sets of points in order to separate the translation compo- nents. Secondly, the scale coefficient and rotation matrix are derived from the regulated positions independent- ly and correlations among transformation model parameters are analyzed. It is indicated that this method is applicable to other sets of non-position data to separate the respective attributions for transformation parameters. 展开更多
关键词 coordinate transformation model Bursa model orthnormal matrix singular value decomposition (SVD) CORRELATION
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The Functional Gradient Description Method of Space Coordinate Transformation 被引量:2
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作者 Pengshuo DUAN Genyou LIU +2 位作者 Youliang GONG Xiaoguang HAO Nazi WANG 《Journal of Geodesy and Geoinformation Science》 2019年第1期66-71,共6页
The 3-dimension coordinate datum transformation is very important in geomatics.Generally,there are small angle coordinate transformation model (i.e.,Bursa model,et al) and large angle coordinate transformation model (... The 3-dimension coordinate datum transformation is very important in geomatics.Generally,there are small angle coordinate transformation model (i.e.,Bursa model,et al) and large angle coordinate transformation model (i.e.,Rodrigo matrix model,et al).However,these papers only focus on the fixed and static situation regardless of the small or large angle.This paper proposes the conception of coordinate transformation gradient field,which can realize the space coordinate transformation from small angle to arbitrary angle,and from static to dynamical.Based on the equivalent characteristics of the unit quaternion rotation matrix and the Rodrigo matrix,through studying the mathematical relationship between the spatial coordinate transformation and the functional gradient,we derive a functional gradient expression of the arbitrary transformation formula in space.The study shows that the essence of spatial coordinate transformation is a kind of potential field mathematically.This potential field conception can unify all the space coordinate transformations.It is the theoretical foundation for the further study of time continuous space coordinate transformation,and this study gives a new solution for the attitude determination of motion carriers. 展开更多
关键词 spatial coordinate transformation functional GRADIENT field COMPLETE EQUIVALENCE
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A VERTICAL COORDINATE TRANSFORMATION FOR 3-D NUMERICAL MODELLING OF OCEAN CIRCULATION
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作者 李鸿雁 方国洪 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1995年第1期31-42,共12页
A so called sine-sigma vertical coordinate transformation is proposed. A vertical implicit scheme is de-rived by using cubic-spline representation of vertical current profiles. The derived 3-D nurmericalmodel has been... A so called sine-sigma vertical coordinate transformation is proposed. A vertical implicit scheme is de-rived by using cubic-spline representation of vertical current profiles. The derived 3-D nurmericalmodel has been applied to simulate the water leved field and the vertical structures of wind-induced cur-rents in an enclosed rectangular region, and the tides in the Bohai Sea. The model is believed to besatisfactory after comparing its results with an analytical soclution and observed data from tidal staions. 展开更多
关键词 VERTICAL coordinate transformation numerical modelling of OCEAN CIRCULATION
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Uzbekistan's coordinate system transformation from CS42 to WGS84 using distortion grid model
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作者 Dilbarkhon Fazilova 《Geodesy and Geodynamics》 CSCD 2022年第1期24-30,共7页
Currently,a non-geocentric geodetic coordinate system introduced in 1942(CS42),based on the Krasovsky ellipsoid and the Baltic system of normal heights introduced in 1977,is used for geodetic works in the Republic of ... Currently,a non-geocentric geodetic coordinate system introduced in 1942(CS42),based on the Krasovsky ellipsoid and the Baltic system of normal heights introduced in 1977,is used for geodetic works in the Republic of Uzbekistan.The development of the GNSS network proposes a task of transition to a new geocentric system based on the World Geodetic System 1984(WGS84)ellipsoid.Many software products adopt 3-or 7-parameter conversions,which can cause errors up to several meters and are not suitable for many applications.In this case,local transformations using a grid of differences between observation points with known coordinates in both datums would give the best accuracy.In this paper,we discuss various interpolation methods(Kriging,Minimum Curvature,Inverse Distance to a Power and Radial Basis Function)to solve the distortion modeling between CS42 and WGS84 systems for national datum improvement.The results show that the distortion models share a common tendency for all interpolation methods:the maximum horizontal displacements are concentrated along the West Tien Shan lineament,which is the boundary of the relief lowering.The discrepancies between the grid-based(calculated)and GPS-measured coordinates are evaluated.Statistical and spatial analysis has confirmed that for the co-ordinate transformation from CS42 to WGS84 and vice versa,grid-based transformation with Radial Basis Function interpolation has a high accuracy transformation.Analysis of the available data across the eastern part of the country shows that some positional distortions existed between the CS42 and WGS84 datums.For the best RBF method,the magnitude of these distortions is about 0.019-0.755 m with a standard deviation of 0.015 m. 展开更多
关键词 CS42 WGS84 coordinate transformation Distortion modeling Interpolation method
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Strong/weak limits and strong/weak differentials of multi-variable indeterminate forms. III: Transformations
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作者 宋光世 《Journal of Chongqing University》 CAS 2004年第2期86-90,共5页
Various transforms of the indeterminate forms are presented in this part, which include simplification in spherical coordinates, origin translation, axis alteration, transformation of limit conservation and applicatio... Various transforms of the indeterminate forms are presented in this part, which include simplification in spherical coordinates, origin translation, axis alteration, transformation of limit conservation and application of Xh?K0. Fundamental factors for numerical simplification are provided respectively for bi-variable indeterminate forms, tri-variable indeterminate forms and the universal extending multiplier. 展开更多
关键词 spherical coordinate indeterminate form multi-variable special form limit conservation transform
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Optimal design of coordination control strategy for distributed generation system
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作者 王爱华 Norapon Kanjanapadit 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第1期51-56,共6页
This paper presents a novel design procedure for optimizing the power distribution strategy in distributed generation system. A coordinating controller, responsible to distribute the total load power request among mul... This paper presents a novel design procedure for optimizing the power distribution strategy in distributed generation system. A coordinating controller, responsible to distribute the total load power request among multiple DG units, is suggested based on the conception of hierarchical control structure in the dynamic system. The optimal control problem was formulated as a nonlinear optimization problem subject to set of constraints. The resulting problem was solved using the Kuhn-Tucker method. Computer simulation results demonstrate that the proposed method can provide better efficiency in terms of reducing total costs compared to existing methods. In addition, the proposed optimal load distribution strategy can be easily implemented in real-time thanks to the simplicity of closed-form solutions. 展开更多
关键词 distributed generation coordination control strategy Kuhn-Tucker method
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Study of Coordination between Protective Devices Comprising Distributed Generation in Distribution System
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作者 Sujarit Muangchareon Atthapol Ngaopitakkul +3 位作者 Sulee Bunjongjit Monthon Leelajindakrairerk Chaichan Pothisarn Auttarat Nawikavatan 《Energy and Power Engineering》 2013年第4期584-588,共5页
This paper proposes to study the coordination of protective devices when 8 MW synchronous generators are interconnected to distribution System of PEA. The coordination between recloser and drop out fuse is investigate... This paper proposes to study the coordination of protective devices when 8 MW synchronous generators are interconnected to distribution System of PEA. The coordination between recloser and drop out fuse is investigated in this paper. The three-phase fault is simulated using digital simulation and electrical network calculation program (DIgSILENT). The results are shown that the short circuit current from substation is reduced comparing to the distribution system without DG connected. It causes to protective device coordination inconsistently, so the maintenance will be delayed more than expected. 展开更多
关键词 COORDINATION DISTRIBUTED generation Protective DEVICE RENEWABLE Energy
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