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Fault Detection and Fault Location in Transmission Line

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Fault Detection and Fault Location in Transmission Line

作者： rana SOHEL 昆明理工大学

学位级别：硕士

由于各种随机原因,在其他电力系统组件之间的传输线遭受意外故障。这些故障会中断电力系统运行的可靠性当发生不可预测的故障时,需要保护系统以防止这些故障的传播并保护系统免受由它们引起的异常操作。这些保护系统的功能是检测和分类... 详细信息

由于各种随机原因,在其他电力系统组件之间的传输线遭受意外故障。这些故障会中断电力系统运行的可靠性当发生不可预测的故障时,需要保护系统以防止这些故障的传播并保护系统免受由它们引起的异常操作。这些保护系统的功能是检测和分类故障,并在检测到电压和/或电流线路的大小时检测故障线路的位置。一旦检测到故障并进行分类,保护继电器就会向断路器发送跳闸信号,以断开(隔离)故障线路。随着电力系统需求的变化和日益复杂化,提出了提高电力系统可靠性保护和故障定位的新要求。随着电力系统故障的发生,传统的基于距离继电器的输电线路保护方法越来越受到重视。有不同类型的开关瞬态产生。例如,在50赫兹(工频)下,由系统中LC元件的谐振引起的较高频率,以及由雷电浪涌引起的非常高的频率瞬变。这些瞬变的幅度和延迟率取决于许多因素,例如故障位置,故障类型,系统参数等。这些瞬变使得难以定义总线电压和线电流之间的关系。很多时候,传统的保护方法无法准确运行。人工神经网络(ANN)可以提供用于检测电力系统故障的新颖解决方案。ANN可以作为一种强大的工具,作为准确有效地解决问题的替代方法。神经网络的特性,例如它们的学习,泛化和并行处理能力,使它们的应用程序成为许多系统的理想选择。使用神经网络作为模式分类器是其最常见和最强大的应用程序之一。

关键词：输电线路人工神经网络继电保护

increased mortality in elderly heart failure patients receiving infusion of furosemide compared to elderly heart failure patients receiving bolus injection

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Journal of Geriatric Cardiology 2020年第6期17卷 359-364页

作者： rana Sager isak Lindstedt Lars Edvinsson Marie-Louise Edvinsson Department of Emergency and internal Medicine Lund University Hospital of SkåneSweden Department of Medicine Institute of Clinical Sciences in LundLund UniversitySweden

Heart failure(HF)is a condition of cardiac dysfunction and fluid *** activation via the reninangiotensin-aldosterone system and the sympathetic nervous system are the pathophysiological cornerstones.[1]Furthermore,HF is a disorder widely associated with grave adverse outcomes and poor prognosis.[2]A loop diuretic is the fundamental drug used to prevent multiorgan failure and improve symptoms in these patients.[3]

关键词： Furosemide Heart failure infusion injection Mortality

Performance of islamic and conventional stock indices:empirical evidence from an emerging economy

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Financial innovation 2015年第1期1卷 229-245页

作者： Md Ejaz rana Waheed Akhter Center of islamic Finance Department of Management SciencesCOMSATS Institute of Information TechnologyLahorePakistan

Background:This study aims to investigate the extent to which the conditional volatilities of both Shari’ah compliant stock and conventional stock are related to those of interest rate and exchange rate in the emerging economy of ***:We used KMi 30 and KSE 100 indices for islamic and conventional stock for the period of July 2008 to November *** employed Generalized Autoregressive Conditional Heteroskedastic in the mean(GARCH-M)*** framework relaxes constancy assumption of classical linear regression(CLRM)model and allows exchange rate and interest rate volatility to evolve over *** GARCHM framework also reveals results about risk-return trade-off in the context of both islamic and conventional stock ***:The findings show positive and statistically significant effect of interest rate volatility on KSE-100,whereas KMi-30 remains unaffected by the *** rate volatility is found to be significant for both conventional and islamic *** relationship of risk coefficient(γ)and stocks returns,as expected,is positive and statistically significant for both KMi-30 and *** result is consistent with the theory of risk-return *** results of parametric t-test show significant difference between returns of both *** implies that Shari’ah compliant stock index(KMi-30)of Pakistan underperforms its conventional ***:By using different performance measures(Sharp ratio,Jensen alpha,Treynor ratio),this study also investigates the hypothesis that islamic stock index has inferior performance compared with unscreened conventional counterparts due to availability of a smaller investment universe,increased monitoring costs,and limited diversification.

关键词： KMi-30 KSE-100 index Shari’ah Exchange rate volatility interest rate volatility Stock Performance etc

Relativistic Energy Pb Projectile Fragmentation with Heavy Target Nuclei

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Chinese Physics Letters 2009年第8期26卷 78-81页

作者： G. Sher M. i. Shahzad M. A. rana Physics Division PINSTECH Post Office Nilore Islamabad Pakistan

We investigate the fragmentation of 158A GeV ^207Tpb projectiles with Bi, Pb, Cu and Ai targets using CR-39 nuclear track detectors. The exposures were made at SPS-CERN. After the etching, the detectors were scanned using an optical microscope to collect the data of etched cone diameters and lengths. We measured the partial charge-changing cross sections using the data of etched cone lengths. The predicted cross sections are compared to similar measurements reported in literature and their dependences on projectile and target mass are described.

关键词： RELATiViTY (Physics) LEAD compounds NUCLEAR fragmentation HEAVY nuclei NUCLEAR track detectors PROTON synchrotrons CROSS sections (Nuclear physics) PHYSiCS literature

Galerkin Finite Element Study on the Effects of Variable Thermal Conductivity and Variable Mass Diffusion Conductance on Heat and Mass Transfer

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Communications in Theoretical Physics 2018年第7期69卷 49-59页

作者： imran Haider Qureshi M.Nawaz Shafia rana T.Zubair Department of Applied Mathematics and Statistics Institute of Space and TechnologyIslamabad

This article investigates the effects of variable thermal conductivity and variable mass diffusion coefficient on the transport of heat and mass in the flow of Casson fluid. Numerical simulations for two-dimensional flow induced by stretching surface are performed by using Galerkin finite element method(GFEM) with linear shape functions. After assembly process, nonlinear algebraic equations are linearized through Picard method and resulting linear system is solved iteratively using Gauss Seidal method with simulation tolerance 10^(-8). Maximum value of independent variableη is searched through numerical experiments. Grid independent study was carried out and error analysis is *** results are validated by comparing with already published results. Parametric study is carried out to explore the physics of the flow. The concentration increases when mass diffusion coefficient is increased. The concentration and thermal boundary layer thicknesses increase when ?_1 and ? are increased. The effect of generative chemical reaction on concentration is opposite to the effect of destructive chemical reaction on the concentration.

关键词： variable diffusion coefficients grid independent study convergence error analysis Nusselt num-ber Casson fluid Joule heating viscous dissipation

Computational engineering analysis of external geometrical modifications on MQ-1 unmanned combat aerial vehicle

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Chinese Journal of Aeronautics 2020年第4期33卷 1154-1165页

作者： Prakash BAGUL Zeeshan A.rana Karl W.JENKiNS LászlóKoNoZSY Centre for Computational Engineering Sciences Cranfield UniversityCranfield MK43 OALUnited Kingdom

This paper focuses on the effects of external geometrical modifications on the aerodynamic characteristics of the MQ-1 predator Unmanned Combat Aerial Vehicle(UCAV)using computational fluid *** investigations are performed for 16 flight conditions at an altitude of7.6 km and at a constant speed of 56.32 m/*** models are analysed,namely the baseline model and the model with external geometrical modifications installed on *** the models are investigated for various angles of attack from-4°to 16°,angles of bank from 0°to 6°and angles of yaw from 0°to 4°.Due to the unavailability of any experimental(wind tunnel or flight test)data for this UCAV in the literature,a thorough verification of calculations process is presented to demonstrate confidence level in the numerical *** analysis quantifies the loss of lift and increase in drag for the modified version of the MQ-1 predator UCAV along with the identification of stall *** improvement(in drag)of up to 96%has been obtained by relocating external modifications,whereas global drag force reduction of roughly 0.5%is *** effects of external geometrical modifications on the control surfaces indicate the blanking phenomenon and reduction in forces on the control surfaces that can reduce the aerodynamic performance of the UCAV.

关键词： Aerodynamics CFD Geometrical modifications MQ-1 predator Turbulent flows Unmanned combat aerial vehicle Unsteady Reynoldsaveraged Navier-Stokes

Einstein Weighted Geometric Operator for Pythagorean Fuzzy Hypersoft with its Application in Material Selection

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2557-2583页

作者： rana Muhammad Zulqarnain imran Siddique Rifaqat Ali Fahd Jarad Aiyared iampan Department of Mathematics Zhejiang Normal UniversityJinhuaChina Department of Mathematics University of Management and TechnologyLahorePakistan Department of Mathematics College of Science and ArtsMuhayilKing Khalid UniversityAbhaSaudi Arabia Department of Mathematics Cankaya UniversityEtimesgutAnkaraTurkey Department of Mathematics King Abdulaziz UniversityJeddahSaudi Arabia Department of Medical Research China Medical University HospitalChina Medical UniversityTaichungTaiwan Department of Mathematics School of ScienceUniversity of PhayaoMae KaMueangPhayaoThailand

Hypersoft set theory is a most advanced form of soft set theory and an innovative mathematical tool for dealing with unclear *** fuzzy hypersoft set(PFHSS)is the most influential and capable leeway of the hypersoft set(HSS)and Pythagorean fuzzy soft set(PFSS).it is also a general form of the intuitionistic fuzzy hypersoft set(iFHSS),which provides a better and more perfect assessment of the decision-making(DM)*** fundamental objective of this work is to enrich the precision of decision-making.A novel mixed aggregation operator called Pythagorean fuzzy hypersoft Einstein weighted geometric(PFHSEWG)based on Einstein’s operational laws has been *** necessary properties,such as idempotency,boundedness,and homogeneity,have been presented for the anticipated PFHSEWG ***-criteria decision-making(MCDM)plays an active role in dealing with the complications of manufacturing design for material ***,conventional methods of MCDM usually produce inconsistent *** on the proposed PFHSEWG operator,a robust MCDM procedure for material selection in manufacturing design is planned to address these *** expected MCDM method for material selection(MS)of cryogenic storing vessels has been established in the real ***,the planned model for handling inaccurate data based on PFHSS is more operative and consistent.

关键词： Pythagorean fuzzy soft set Pythagorean fuzzy hypersoft set Pythagorean fuzzy hypersoft Einstein weighted geometric operator(PFHSEWG) MCDM

Aggregation Operators for interval-Valued Pythagorean Fuzzy Hypersoft Set with Their Application to Solve MCDM Problem

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 619-651页

作者： rana Muhammad Zulqarnain imran Siddique Rifaqat Ali Fahd Jarad Aiyared iampan Department of Mathematics University of Management and TechnologySialkot CampusLahore51310Pakistan Department of Mathematics University of Management and TechnologyLahore54000Pakistan Department of Mathematics College of Science and ArtsKing Khalid UniversityAbha61413Saudi Arabia Department of Mathematics Cankaya UniversityAnkara06790Turkey Department of Mathematics King Abdulaziz UniversityJeddah22254Saudi Arabia Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung404332Taiwan Department of Mathematics School of ScienceUniversity of PhayaoMae KaMueangPhayao56000Thailand

Experts use Pythagorean fuzzy hypersoft sets(PFHSS)in their investigations to resolve the indeterminate and imprecise information in the decision-making *** operators(AOs)perform a leading role in perceptivity among two circulations of prospect and pull out concerns from that *** this paper,we extend the concept of PFHSS to interval-valued PFHSS(iVPFHSS),which is the generalized form of intervalvalued intuitionistic fuzzy soft *** iVPFHSS competently deals with uncertain and ambagious information compared to the existing interval-valued Pythagorean fuzzy soft *** is the most potent method for amplifying fuzzy data in the decision-making(DM)*** operational laws for iVPFHSS have been *** on offered operational laws,two inventive AOs have been established:interval-valued Pythagorean fuzzy hypersoft weighted average(iVPFHSWA)and interval-valued Pythagorean fuzzy hypersoft weighted geometric(iVPFHSWG)operators with their essential ***-criteria group decision-making(MCGDM)shows an active part in contracts with the difficulties in industrial enterprise for material ***,the prevalent MCGDM approaches consistently carry irreconcilable *** on the anticipated AOs,a robust MCGDMtechnique is deliberate formaterial selection in industrial enterprises to accommodate this shortcoming.A real-world application of the projectedMCGDMmethod for material selection(MS)of cryogenic storing vessels is *** impacts show that the intended model is more effective and reliable in handling imprecise data based on iVPFHSS.

关键词： interval-valued pythagorean fuzzy hypersoft set iVPFHSWA operator iVPFHSWG operator MCGDM

Entropy generation analysis of tangent hyperbolic fluid in quadratic Boussinesq approxima.ion using spectral quasi-linearization method

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Applied Mathematics and Mechanics(English Edition) 2021年第10期42卷 1525-1542页

作者： C.SRiNiVAS REDDY B.MAHANTHESH P.rana K.S.NiSAR Department of Mathematics Government City CollegeTelangana 500002India Department of Mathematics CHRIST(Deemed to be University)Bengaluru 560029India School of Mathematical Sciences College of Science and TechnologyWenzhou-Kean UniversityWenzhou 325060China Department of Mathematics College of Arts and SciencesPrince Sattam bin Abdulaziz UniversityWadi Aldawaser 11991Saudi Arabia

in many industrial applications,heat transfer and tangent hyperbolic fluid flow processes have been garnering increasing attention,owing to their immense importance in technology,engineering,and *** processes are relevant for polymer solutions,porous industrial materials,ceramic processing,oil recovery,and fluid *** present tangent hyperbolic fluid flow and heat transfer model accurately predicts the shear-thinning phenomenon and describes the blood flow ***,the entropy production analysis of a non-Newtonian tangent hyperbolic material flow through a vertical microchannel with a quadratic density temperature fluctuation(quadratic/nonlinear Boussinesq approxima.ion)is performed in the present *** impacts of the hydrodynamic flow and Newton’s thermal conditions on the flow,heat transfer,and entropy generation are *** governing nonlinear equations are solved with the spectral quasi-linearization method(SQLM).The obtained results are compared with those calculated with a finite element method and the bvp4c *** addition,the effects of key parameters on the velocity of the hyperbolic tangent material,the entropy generation,the temperature,and the Nusselt number are *** entropy generation increases with the buoyancy force,the pressure gradient factor,the non-linear convection,and the Eckert *** non-Newtonian fluid factor improves the magnitude of the velocity *** power-law index of the hyperbolic fluid and the Weissenberg number are found to be favorable for increasing the temperature *** buoyancy force caused by the nonlinear change in the fluid density versus temperature improves the thermal energy of the system.

关键词： tangent hyperbolic fluid nonlinear Boussinesq approxima.ion entropy production convective boundary condition spectral quasi-linearization method(SQLM)