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Multi-stage Defender-Attacker-Defender Model for Distribution System Resilience Enhancement in Ice Storms with Line Hardening,Mobile Device and Repair Crew Dispatching

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1103-1118页

作者： Ran Tao dongmei zhao Haoxiang Wang Xuan Xia School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China State Grid Shaoxing Power Supply Company Shaoxing 312000China

This paper proposes a co-optimal strategy using line hardening,mobile devices(mobile ice-melting device,mobile emergency generator,mobile energy storage system),and repair crew dispatching to improve distribution system resilience during ice storms.A multi-stage defender-attacker-defender model is established to take into account interactions and coupling relationships between different *** our proposed model,ice storms will attack the distribution and transportation system in a worst-case scenario,affecting system performance from various *** to the different operating states in the distribution system affected by ice storms,aiming at minimizing the weighted load shedding value,this paper applies various measures to different stages to improve the response and defense capabilities to ice storms and realize restoration of the distribution system *** nested column-and-constraint generation algorithm is used to solve the model *** effectiveness of the proposed model and solution method for enhancing the distribution system resilience is verified on the modified IEEE 33-bus distribution system and modified realworld zone of Caracas 141-bus distribution system.

关键词： Defender-attacker-defender model distribution system resilience ice storm line hardening mobile device repair crew

Economic optimization of smart distribution networks considering real-time pricing

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Journal of Modern Power Systems and Clean Energy 2014年第4期2卷 350-356页

作者： Hong ZHANG dongmei zhao Chenghong GU Furong LI Bo WANG North China Electric Power University Beijing 102206China University of Bath Bath BA27AYUK

With the development of smart meters,a realtime pricing(RTP)demand response is becoming possible for households in distribution *** power flow can be bidirectional in distribution networks which become smarter with distributed generators(DGs).It is expensive to import electricity from the generation far from load centers because of the cost of power loss and network use,so that it is more economical to use electricity generated by local distributed ***,in order to curtail operating costs of distribution networks,this paper proposes a model of economic optimization conducted by distribution network *** electricity purchasing costs for distribution network operators are minimized by optimizing electric power from transmission systems and local distributed ***,based on price elasticity,the formulations of load demand considering RTP are proposed with economic optimization of distribution *** economic optimization problems are resolved by an interior point *** case study shows that peak load demand can be reduced about 3.5%because the household RTP and electricity purchasing costs of distribution network operators can save 28.86£every hour.

关键词： Distribution network Economic operation Electricity cost Real-time pricing

Spectrum features of commercial derv fuel oils in the terahertz region

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Science China(Physics,Mechanics & Astronomy) 2012年第2期55卷 195-198页

作者： zhao Hui zhao Kun TIAN Lu zhao SongQing ZHOU QingLi SHI YuLei zhao dongmei ZHANG CunLin State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Laboratory of Optic Sensing and Detecting Technology College of ScienceChina University of PetroleumBeijing 102249China Beijing Key Laboratory for Terahertz Spectroscopy and Imaging Key Laboratory ofTerahertz OptoelectronicsMinistry of EducationDepartment of PhysicsCapital Normal UniversityBeijing 100048China International Center for Materials Physics Chinese Academy of SciencesShenyang 110016China

Characteristic spectra in the 0.5-2.5 terahertz (THz) range of three commercial derv fuel oils have been obtained using THz time-domain spectroscopy and calculated using density functional *** simulated results and experimental absorption curves suggest that the skeleton vibration is predominant in the THz region,and the absorption bumps of diesels are a superposition of various *** investigation demonstrates that different diesels can be distinguished using THz time-domain spectroscopy and THz technology is a promising method to detect the composition and properties of diesels via chemical analysis.

关键词： optical constants derv fuel oil time-domain analysis terahertz radiation

A RISK ASSESSMENT METHOD OF THE WIRELESS NETWORK SECURITY

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Journal of Electronics(China) 2007年第3期24卷 428-432页

作者： zhao dongmei Wang Changguang Ma Jianfeng College of Computer Science and Technology Xidian University Xi＇an 710071 China

The core of network security is the risk assessment. In this letter,a risk assessment method is introduced to estimate the wireless network security. The method,which combines Analytic Hier-archy Process (AHP) method and fuzzy logical method,is applied to the risk assessment. Fuzzy logical method is applied to judge the important degree of each factor in the aspects of the probability,the influence and the uncontrollability,not to directly judge the important degree itself. The risk as-sessment is carved up 3 layers applying AHP method,the sort weight of the third layer is calculated by fuzzy logical method. Finally,the important degree is calculated by AHP method. By comparing the important degree of each factor,the risk which can be controlled by taking measures is known. The study of the case shows that the method can be easily used to the risk assessment of the wireless network security and its results conform to the actual situation.

关键词： Wireless network Risk assessment Analytic Hierarchy Process (AHP) method Fuzzy logical method

An Investigation of Landslide Susceptibility Using Logistic Regression and Statistical Index Methods in Dailekh District, Nepal

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Chinese Geographical Science 2022年第5期32卷 834-851页

作者： DIL Kumar RAI XIONG Donghong zhao Wei zhao dongmei ZHANG Baojun NIRMAL Mani DAHAL WU Yanhong MUHAMMAD Aslam BAIG Institute of Mountain Hazards and Environment(IMHE) Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Kathmandu Center for Research and Education Chinese Academy of Sciences-Tribhuvan UniversityKathmandu 44613Nepal

Landslide distribution and susceptibility mapping are the fundamental steps for landslide-related hazard and disaster risk management activities, especially in the Himalaya region which has resulted in a great deal of death and damage to property. To better understand the landslide condition in the Nepal Himalaya, we carried out an investigation on the landslide distribution and susceptibility using the landslide inventory data and 12 different contributing factors in the Dailekh district, Western Nepal. Based on the evaluation of the frequency distribution of the landslide, the relationship between the landslide and the various contributing factors was ***, the landslide susceptibility was calculated using logistic regression and statistical index methods along with different topographic(slope, aspect, relative relief, plan curvature, altitude, topographic wetness index) and non-topographic factors(distance from river, normalized difference vegetation index(NDVI), distance from road, precipitation, land use and land cover, and geology), and 470(70%) of total 658 landslides. The receiver operating characteristic(ROC) curve analysis using 198(30%) of total landslides showed that the prediction curve rates(area under the curve, AUC) values for two methods(logistic regression and statistical index) were 0.826, and 0.823with success rates of 0.793, and 0.811, respectively. The values of R-Index for the logistic regression and statistical index methods were83.66 and 88.54, respectively, consisting of high susceptible hazard classes. In general, this research concluded that the cohesive and coherent natural interplay of topographic and non-topographic factors strongly affects landslide occurrence, distribution, and susceptibility condition in the Nepal Himalaya region. Furthermore, the reliability of these two methods is verified for landslide susceptibility mapping in Nepal’s central mountain region.

关键词： landslide characteristics landslide susceptibility logistic regression statistical index Nepal Himalaya

Carrier dynamics and terahertz photoconductivity of doped silicon measured by femtosecond pump-terahertz probe spectroscopy

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Science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1944-1948页

作者： ZHOU QingLi SHI YuLei LI Tong JIN Bin zhao dongmei ZHANG CunLin Beijing Key Laboratory for Terahertz Spectroscopy and Imaging Key Laboratory of Terahertz OptoelectronicsMinistry of EducationDepartment of PhysicsCapital Normal UniversityBeijing 100048China Department of Electronics Engineering Tianjin University of Technology and EducationTianjin 300222China

The carrier dynamics and terahertz photoconductivity in the n-type silicon (n-Si) as well as in the p-type Silicon (p-Si) have been investigated by using femtosecond pump-terahertz probe technique. The measurements show that the relative change of terahertz transmission of p-Si at low pump power is slightly smaller than that of n-Si,due to the lower carrier density induced by the recombination of original holes in the p-type material and the photogenerated electrons. At high pump power,the bigger change of terahertz transmission of p-Si originates from the greater mobility of the carriers compared to n-Si. The transient photoconductivities are calculated and fit well with the Drude-Smith model,showing that the mobility of the photogenerated carriers decreases with the increasing pump power. The obtained results indicate that femtosecond pump-terahertz probe technique is a promising method to investigate the carrier dynamics of semiconductors.

关键词： semiconductor terahertz carrier dynamics

Toward Improved Accuracy in Quasi-Static Elastography Using Deep Learning

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 911-935页

作者： Yue Mei Jianwei Deng dongmei zhao Changjiang Xiao Tianhang Wang Li Dong Xuefeng Zhu Department of Engineering Mechanics State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of TechnologyDalian116023China International Research Center for Computational Mechanics Dalian University of TechnologyDalian116023China DUT-BSU Joint Institute Dalian University of TechnologyDalian116023China Department of Automotive Engineering Tongji UniversityShanghai201804China *** SeattleWA98109USA School of Automotive Engineering Dalian University of TechnologyDalian116023China

Elastography is a non-invasive medical imaging technique to map the spatial variation of elastic properties of soft *** quality of reconstruction results in elastography is highly sensitive to the noise induced by imaging measurements and *** address this issue,we propose a deep learning(DL)model based on conditional Generative Adversarial Networks(cGANs)to improve the quality of nonhomogeneous shear modulus *** train this model,we generated a synthetic displacement field with finite element simulation under known nonhomogeneous shear modulus *** the simulated and experimental displacement fields are used to validate the proposed *** reconstructed results demonstrate that the DL model with synthetic training data is able to improve the quality of the reconstruction compared with the well-established optimization ***,we emphasize that our DL model is only trained on synthetic *** might provide a way to alleviate the challenge of obtaining clinical or experimental data in ***,this work addresses several fatal issues in applying the DL technique into elastography,and the proposed method has shown great potential in improving the accuracy of the disease diagnosis in clinical medicine.

关键词： Nonhomogeneous elastic property distribution reconstruction deep learning finite element method inverse problem elastography conditional generative adversarial network

The effect of the direct current electric field on the dynamics of the ultracold plasma

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Plasma Science and Technology 2018年第8期20卷 6-10页

作者： Syed ZAHEERUDDIN Yufan LI dongmei zhao Xinwen MA Jie YANG Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 People' s Republic of China University of Chinese Academy of Sciences Beijing 100049 People's Republic of China

We created an ultracold plasma by photoionizing the laser-cooled and trapped rubidium atoms in a magneto-optical trap. In the externally applied direct current（DC） electric field environment,the electrons which escape from the potential well of the ultracold plasma were detected for different numbers of the ions and initial kinetic energies of the electrons. The results are in good agreement with the calculations, based on the Coulomb potential well model, indicating that the external DC field is an effective tool to adjust the depth of potential well of the plasma, and it is possible to create an ultracold plasma in a controlled manner.

关键词： ultracold plasma magneto-optical trap photoionization Coulomb potential well model

An Optimal Dynamic Generation Scheduling for a Wind-Thermal Power System

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Energy and Power Engineering 2013年第4期5卷 1016-1021页

作者： Xingyu Li dongmei zhao School of Electrical and Electronic Engineering North China Electric Power University Beijing China

In this paper, a dynamic generation scheduling model is formulated, aiming at minimizing the costs of power generation and taking into account the constraints of thermal power units and spinning reserve in wind power integrated systems. A dynamic solving method blended with particle swarm optimization algorithm is proposed. In this method, the solution space of the states of unit commitment is created and will be updated when the status of unit commitment changes in a period to meet the spinning reserve demand. The thermal unit operation constrains are inspected in adjacent time intervals to ensure all the states in the solution space effective. The particle swarm algorithm is applied in the procedure to optimize the load distribution of each unit commitment state. A case study in a simulation system is finally given to verify the feasibility and effectiveness of this dynamic optimization algorithm.

关键词： Generation Scheduling Dynamic Optimization Wind Power Particle Swarm Optimization