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Fault location of untransposed double-circuit transmission lines based on an improved Karrenbauer matrix and the QPSO algorithm

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Protection and Control of Modern Power Systems 2023年第3期8卷 139-152页

作者： Minan tang Hang Lu bin Li School of New Energy and Power Engineering Lanzhou Jiaotong UniversityLanzhouChina School of Electrical and Information Engineering Tianjin UniversityTianjinChina.

Some double-circuit transmission lines are untransposed,which results in complex coupling relations between the parameters of the transmission *** the traditional modal transformation matrix is directly used to decouple the parameters,it can lead to large errors in the decoupled modal parameter,errors which will be amplified in the fault location ***,it makes the fault location results of the untransposed double-circuit transmission lines less ***,a new modal transformation method is needed to decou-ple the parameter matrix of untransposed double-circuit transmission lines and realize the fault location according to the decoupled modal *** improving the basis of the Karrenbauer matrix,a modal transformation matrix suitable for decoupling parameters of untransposed double-circuit transmission lines is *** address the dif-ficulties in solving the fault location equation of untransposed double-circuit transmission lines,a new fault location method based on an improved Karrenbauer matrix and the quantum-behaved particle swarm optimization(QPSO)algorithm is ***,the line parameter matrix is decomposed into identical and inverse sequence compo-nents using the identical-inverse sequence component *** Karrenbauer matrix is then transformed to obtain the improved Karrenbauer matrix for untransposed double-circuit transmission lines and applied to identi-cal and inverse sequence components to solve the decoupled modal ***,based on the principle that voltage magnitudes at both ends are equal,the fault location equation is expressed using sequence compo-nents at each end,and the QPSO algorithm is introduced to solve the ***,the feasibility and accuracy of the proposed method are verified by PSCAD *** simulation results fully demonstrate that the innova-tive improvement on the basis of the traditional modal transformation matrix in this paper can realize the m

关键词： Fault location Untransposed double-circuit transmission lines Karrenbauer matrix Quantum particle

Ergodic rate analysis for full-duplex NOMA networks with energy harvesting

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Science China(Information Sciences) 2021年第8期64卷 255-256页

作者： bin ZHONG Long CHEN Zhijun tang School of Information and Electrical Engineering Hunan University of Science and Technology

Dear editor,Non-orthogonal multiple access(NOMA), regarded as a promising technique for substantially increasing the spectral efficiency of wireless networks that comprise massive devices, has exhibited a number of significant performance advantages, including the reduced latency, improved reliability,and the capability of offering a higher sum ***,

关键词： Ergodic rate analysis for full-duplex NOMA networks with energy harvesting SWIPT

The Structure and Elastic and Thermodynamic Properties of Cubic-NbH_(2) under High Pressures from First-Principles Calculations

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Chinese Physics Letters 2013年第6期30卷 161-164页

作者： LIU Xian-Kun tang bin Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsCAEPMianyang 621900

NbH_(2) hydride is an important material in hydrogen storage ***,until now there have been no experimental and theoretical data on the elastic and thermodynamic *** structure and thermodynamic properties of cubic-NbH_(2) under high temperatures and pressure are investigated by first-principles study based on the pseudo-potential plane-wave density functional theory method using the generalized gradient approximation and quasi-harmonic Debye *** results show that the calculated structural parameters of NbH2 are in good agreement with the available experimental results and other theoretical *** obtained elastic constants satisfy the requirement for mechanical stability,indicating that the NbH_(2) crystal is stable in the investigated pressure and temperature *** the quasi-harmonic Debye model,in which the phononic effects are considered,the thermodynamic properties of NbH_(2),such as the thermal expansion coefficient and the heat capacity dependence of temperature and pressure in the ranges 0–1100K and 0–70GPa,are also obtained,respectively.

关键词： thermodynamic Debye Elastic

Considering Monopoly Maintenance Cost for an Automobile Purchase in China: A DEA-Based Approach

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Journal of Systems Science & Complexity 2019年第4期32卷 1167-1179页

作者： dai Qianzhi LI Lin LEI Xiyang AN Qingxian tang Xiao School of Economics Hefei University of TechnologyHefei 230009China Center for Industrial Information and Economic Research Hefei University of TechnologyHefei 230009China Academy of Mathematics and Systems Science Chinese Academy of ScienceBeijing 100190China School of Management Hefei University of TechnologyHefei 230009China School of Business Central SouthUniversityChangsha 410083China School of Management University of Science and Technology of ChinaHefei 230026China

With the fast growing economy,China has become the biggest automobile market in the *** Chinese families buy automobiles to promote individual wellbeing and facilitate the convenience of *** purchase has become a general and important decision for a Chinese ***,it is always difficult to make a decision on the automobile purchase that balance the automobiles performance and its ***,the automobile maintenance market in China is ***,the maintenance cost is a significant consideration in automobile purchase *** paper employs the concept of data envelopment analysis(DEA)to measure cost performance of the automobile with considering the monopoly maintenance *** RCA(ratio of the total price of accessories of an automobile to the price of the automobile)100 index system is used to represent the maintenance cost of each *** structure of the automobile maintenance market can be reflected with including the RCA 100 index system in the performance *** of the case study of 28 automobiles in China verify the necessity of considering the maintenance cost in automobile purchase decision.

关键词： Automobile purchase business analytics cost performance data envelopment analysis(DEA) monopoly maintenance cost

Evaluation of Nonbreaking Wave-Induced Mixing Parameterization Schemes Based on a One-Dimensional Ocean Model

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Journal of Ocean University of China 2024年第3期23卷 567-576页

作者： tang Ran HUANG Chuanjiang dai Dejun WANG Gang The First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Surface waves have a considerable effect on vertical mixing in the upper *** the past two decades,the vertical mixing induced through nonbreaking surface waves has been used in ocean and climate models to improve the simulation of the upper *** far,several nonbreaking wave-induced mixing parameterization schemes have been proposed;however,no quantitative comparison has been performed among *** this paper,a one-dimensional ocean model was used to compare the performances of five schemes,including those of Qiao et al.(Q),Hu and Wang(HW),Huang and Qiao(HQ),Pleskachevsky et al.(P),and Ghantous and Babanin(GB).Similar to previous studies,all of these schemes can decrease the simulated sea surface temperature(SST),increase the subsurface temperature,and deepen the mixed layer,thereby alleviating the common thermal deviation problem of the ocean model for upper ocean *** these schemes,the HQ scheme exhibited the weakest wave-induced mixing effect,and the HW scheme exhibited the strongest effect;the other three schemes exhibited roughly the same *** particular,the Q and P schemes exhibited nearly the same *** the simulation based on observations from the Ocean Weather Station Papa,the HQ scheme exhibited the best performance,followed by the Q *** the experiment with the HQ scheme,the root-mean-square deviation of the simulated SST from the observations was 0.43℃,and the mixed layer depth(MLD)was 2.0 *** a contrast,the deviations of the SST and MLD reached 1.25℃ and 8.4 m,respectively,in the experiment without wave-induced mixing.

关键词： wave-induced mixing surface waves sea surface temperature mixed layer depth General Ocean Turbulence Model

Recent advances in the synthesis and applications of furocoumarin derivatives

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Chinese Chemical Letters 2023年第9期34卷 119-133页

作者： Chaoyue Chen Zheng-bin tang Zhichang Liu School of Chemistry and Chemical Engineering Jiangsu University of TechnologyChangzhou 213001China Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake Universityand Westlake Institute for Advanced StudyHangzhou 310030China

Furocoumarins are an important class of heterocyclic compounds with a fused tricyclic structure of coumarin and furan *** are commonly found in bioactive natural products and have a diverse range of biological and pharmaceutical properties,including cytotoxicity,photosensitivity,insecticidal,antibacterial,and antifungal activity,among *** elegant linear/angular tricyclic skeleton and superior pharmacological properties,make them ideal for building and developing advanced biological scaffolds for biomedical *** a result,the family of furocoumarins has been the focus of intensive research,and lots of encouraging progress have been achieved in recent *** review summarizes the most recent methods reported for the synthesis of the furocoumarin derivative family,along with their applications in medicinal chemistry covering from 2018 to 2022.

关键词： Furocoumarin Coumarin Furan Synthesis Pharmaceutical activity Applications

Design and simulation of digital channelized receivers in fractional Fourier domain

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Journal of Systems Engineering and Electronics 2013年第1期24卷 36-43页

作者： Pengfei tang bin Yuan Qinglong Bao Zengping Chen ATR Key Lab School of Electronic Science and EngineeringNational University of Defense Technology

An approach is proposed to realize a digital channelized receiver in the fractional Fourier domain （FRFD） for signal intercept applications. The presented architecture can be considered as a generalization of that in the traditional Fourier domain. Since the linear frequency modulation （LFM） signal has a good energy concentration in the FRFD, by choosing an appropriate fractional Fourier transform （FRFT） order, the presented architecture can concentrate the broadband LFM signal into only one sub-channel and that will prevent it from crossing several sub-channels. Thus the performance of the signal detection and parameter estimation after the sub-channel output will be improved significantly. The computational complexity is reduced enormously due to the implementation of the polyphase filter bank decomposition, thus the proposed architecture can be realized as efficiently as in the Fourier domain. The related simulation results are presented to verify the validity of the theories and methods involved in this paper.

关键词： digital channelized receiver fractional Fourier domain(FRFD) convolution theorem sampling theorem.

Graph Computing Based Security Constrained Unit Commitment in Hydro-thermal Power Systems Incorporating Pumped Hydro Storage

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 485-496页

作者： Longfei Wei Guangyi Liu Shen Yan Renchang dai Yachen tang Hitachi ABB Power Grids San JoseCAUSA School of Electrical Engineering Xi'an University of TechnologyXi'anChina Department of Industrial and Enterprise Systems Engineering University of Illinois at Urbana-ChampaignChampaignILUSA Puget Sound Energy BellevueWAUSA Envision Digital Inc. Redwood CityCAUSA

This paper proposes a graph computing based mixed integer programming(MIP)framework for solving the security constrained unit commitment(SCUC)problem in hydro-thermal power systems incorporating pumped hydro storage(PHS).The proposed graph computing-based MIP framework considers the economic operations of thermal units,cascade hydropower stations and PHS stations,as well as their technical impacts towards the network ***,the hydro-thermal power system data and unit information are stored in a graph structure with nodes and edges,which enables nodal and hierarchical parallel computing for the unit commitment(UC)solution calculation and network security analysis.A MIP model is then formulated to solve the SCUC problem with the mathematical models of thermal units,cascade hydropower stations and PHS *** addition,two optimization approaches including convex hull reformulation(CHR)and special ordered set(SOS)methods are introduced for speeding up the MIP calculation *** ensure the system stability under the derived UC solution,a parallelized graph power flow(PGPF)algorithm is proposed for the hydro-thermal power system network security ***,case studies of the IEEE 118-bus system and a practical 2749-bus hydro-thermal power system are introduced to demonstrate the feasibility and validity of the proposed graph computing-based MIP framework.

关键词： Graph computing hydro-thermal system mixed integer programming network security unit commitment

Fabrication and boiling heat transfer characterization of multiscale microgroove surfaces

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Science China(Technological Sciences) 2022年第12期65卷 3010-3019页

作者： tang Heng GUO bin tang Yong WU XiaoYu PENG RuiTao SUN YaLong Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518000China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China School of Mechanical Engineering Xiangtan UniversityXiangtan 411105China

Microstructural functional surfaces play an important role in energy conversion applications including power generation,air conditioning,and thermal management of electronics through the boiling *** this study,multi-scale microgroove surfaces were fabricated by the combination of wire electrical discharge machining(WEDM)and electrical discharge shaped machining(EDSM)to achieve a better boiling *** WEDM,with the advantage of high efficiency,was used to fabricate the first microgroove array,and rougher surfaces were formed by intense discharge.A wavy electrode was used in EDSM to fabricate the second microgroove *** cavities at the intersections of microgrooves and rougher micro fins with spacing distribution were formed after *** boiling performance of the multi-scale microgroove surface was studied with water as the working medium under atmospheric *** results indicated that the boiling performance of the microgroove surface is significantly *** critical heat flux and maximum heat transfer coefficient of microgroove surface were higher than the surfaces fabricated only by WEDM or EDSM,which were 2.34 and 3.29 times that of smooth copper plate,*** study demonstrated that the combination of WEDM and EDSM is a convenient and effective method to fabricate high-performance microgroove boiling surfaces.

关键词： multi-scale microgroove electrical discharge machining reentrant cavity boiling performance