电力系统正常运行动态多模块数字实时仿真

电力系统数学实时仿真中已广泛应用于多模块并行处理技术,针对两边带机双回传输线正常运行状态提出了新的多模块耦合模型,并给出了数字积分方法,通过对一个具体电力系统的仿真,在Ｐｅｎｔｉｕｍ Ｐｒｏ ＳＭＰ构成的并行处理系统上数字仿真结果表明,新的多模块耦合模型是正确的,所选用的数字积分法是适合于实时仿真的。     

35 kV馈电系统正常运行数字仿真的多模块模型

建立了35kV馈电系统正常运行数字仿真的多模块模型的数学模型，并在已知同步发电机与综合负载模型的基础上，进一步提出了适合于该电力传输系统数字实时仿真的多模块耦合模型，同时给出了相应的数字积分方法，在奔腾Ⅲ500计算机上的运行结果表明，所提出的模型和选用的数字积分方法是正确的，并且能实时实现。     

35 kV输电线级联数字实时仿真模型

建立了35kV输电线正常运行状态级联集中参数数字仿真的数学模型,并在已知同步发电机、变压器和综合负载模型的基础上,进一步提出了适合于35kV馈电系统数字实时仿真的多模块耦合模型,同时给出了相应的数字积分方法。在奔腾Ⅲ500机上的运行结果表明,所提出的模型是正确的,选用的数字积分方法是合适的,并且能实时实现。     

高压短环形电力系统数字仿真的多模块模型

建立了高压短距离环形电力传输线的数学模型,并在已知同步发电机与综合负载模型的基础上,进一步提出了适合于该电力传输系统数字实时仿真的多模块耦合模型,同时给出了相应的数字积分方法．一个仿真实例在奔腾Ⅱ333机上的运行结果表明,所提出的模型和选用的数字积分方法是正确的,并且能实时实现．     

馈电系统非全相运行的数学模型及其仿真

高压短距离35 kV馈电传输系统，是最常用的短距离电力系统之一.按照物理设备对系统进行分块，对系统传输线模块用集总参数模型、同步发电机、变压器、综合负载分别作为独立模块建模，各模块的连接处用解耦电压源替代，这样就可对各模块平行地进行数字积分.在已知同步发电机与综合负载模型的基础上，建立了馈电系统非全相运行数字仿真的数学模型，同时给出了相应的数字积分方法.在奔腾Ⅲ计算机上的运行结果表明，所提出的模型和选用的数字积分方法是正确的，并且能实时实现.     

远距离电力传输系统的多模块数字实时仿真

在两边带机的双回高压远距离传输线的分块耦合模型的基础上 ,进一步对两边带机和综合负载的双回高压远距离传输线的故障状态提出了分块耦合模型 ,并给出了数字积分方法 .一个具体仿真实例在PentiumⅡ 2 66机上的运行结果表明 ,该模型是正确的 ,所选用的数字积分方法是适合于实时仿真的     

模块化虚拟液压仿真系统研究

液压系统的仿真,一直滞后于机械和电气系统。计算机和虚拟仪器技术的快速发展,给模块化构建虚拟液压系统提供了技术支撑。用虚拟仪器图形化编程软件,可以构建各液压元件的仿真模型,建立元件耦合模块,用液压元件仿真模型就可以建立虚拟液压系统仿真模型。虚拟仪器能够将真实的设备与虚拟仿真模型连接起来,将设备运行时的参数实时输入仿真模型,实现对系统运行监测和故障预报。采用该技术提高了液压技术水平,拓展了虚拟仪器的概念,真正实现了虚实结合,将虚拟仪器拓展为虚拟仪器仿真系统。     

电力变压器的数学模型与仿真的研究

提出了一个三相、双绕组、Y0 /Δ - 11电力变压器 (由三个单相变压器组成 )的实时仿真模型 ,给出了合适的数字积分方法 ,并对该变压器空载合闸的合闸涌流的电磁暂态过程及正常负载运行过程进行了仿真 .仿真实例在PC机系统上的运行结果表明 ,所提出的模型和选用的数字积分方法是正确的 ,并且能实时实现     

STEP-NC仿真系统研究

为满足STEP-NC数控系统研究的需要,提出基于STEP-NC仿真系统的方案.该系统采用模块化设计,译码器由解析模块、建模模块和路径规划模块构成,根据STEPNC程序特点完成程序解析、加工类库模型建立和刀具路径规划功能,其他模块完成实时加工仿真功能.作为独立模块的译码器,其数据接口用于仿真系统与实际数控系统进行数据交换,其路径信息接口设计为直线和圆弧两种单元类型,作为仿真和加工的计算依据.仿真和加工实验证明该仿真系统运行正确,说明基于STEP-NC仿真系统及译码器可以作为独立的功能模块嵌入数控系统.     

Y0/Y0/Δ自耦变压器的数字实时仿真

提出了一个三相Y0 /Y0 /Δ - 12 - 11电力自耦变压器的实时仿真模型 ,给出了有效的数字积分方法 ,对该变压器空载合闸涌流的电磁暂态过程及负载运行过程进行了仿真 .仿真实例在PC机系统上的运行结果表明 ,所提出的模型和选用的数字积分方法是正确的     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

正~~