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Journal of Modern Power Systems and Clean Energy 2020年第4期8卷 750-759页

作者： Yingjun Wu Hao Xu ming ni College of Energy and Electrical Engineering Hohai UniversityNanjingChina College of Automation&College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjingChina College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjingChina NARI Group Corporation(State Grid Electric Power Research Institute) NanjingChina

With the widespread use of communication and information technology,power system has been evolving into cyber-physical power system(CPPS)and becoming more vulnerable to ***,it is necessary to enhance the ability of the communication and information system in CPPS to defend against *** paper proposes a method to enhance the survivability of the communication and information system in ***,the communication and information system for critical business of power system is decomposed into certain types of atomic services,and then the survivability evaluation indexes and their corresponding calculation method for the communication and information system are ***,considering the efficacy and cost defensive resources,a defensive resource allocation model is proposed to maximize the survivability of communication and information system in ***,a modified genetic algorithm is adopted to solve the proposed ***,the simulation results of CPPS for an IEEE 30-node system verify the proposed method.

关键词： Cyber-physical power system(CPPS) cyber-attacks survivability evaluation communication and information system defensive resource

Fully Distributed Economic Dispatch for Cyber-physical Power System with Time Delays and Channel Noises

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1472-1481页

作者： Yuhang Zhang ming ni Yonghui Sun College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China NARI Group Corporation(State Grid Electric Power Research Institute) Nanjing 211106China NARI Technology Co. Ltd.Nanjing 211106China State Key Laboratory of Smart Grid Protection and Control Nanjing 211106China

Economic dispatch problem(EDP)is a fundamental optimization problem in power system operation,which aims at minimizing the total generation *** fact,the power grid is becoming a cyber-physical power system(CPPS).Therefore,the quality of communication is a key *** this paper,considering two important factors,i.e.,time delays and channel noises,a fully distributed consensus based algorithm is proposed for solving *** critical maximum allowable upper bounds of heterogeneous communication delays and self-delays are *** should be pointed out that the proposed algorithm can be robust against the time-varying delays and channel noises considering generator *** addition,even with time-varying delays and channel noises,the power balance of supply and demand is not broken during the *** simulation studies are presented to validate the correctness and superiority of the developed results.

关键词： Distributed economic dispatch consensus-based algorithm cyber-physical power system time delay channel noises

Cyber-attack-tolerant Frequency Control of Power Systems

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 307-315页

作者： Chunyu Chen Kaifeng Zhang ming ni Ying Wang the School of Electrical and Power Engineering China University of Mining and TechnologyXuzhou 221116China the School of Automation Southeast UniversityNanjing 210096China NARI Group Corporation(State Grid Electric Power Research Institute) Nanjing 211106China NARI Technology Co. Ltd.Nanjing 211106China State Key Laboratory of Smart Grid Protection and Control Nanjing 211106China

Cyber attacks are emerging threats in the Internet of Things applications,and power systems are typical cyber attack *** one of the most essential operation functions,frequency control is threatened by cyber intrusions,and the existing centralized control mode cannot effectively address cyber *** this study,a new distributed cyber-attack-tolerant frequency control scheme is *** distributed control mode also serves as a convenient tool for attack *** designed cyber-attack-tolerant frequency controller adopts the idea of passive fault attenuation,thus simplifying the design *** the aid of graph theory and consensus techniques,distributed integral based and model predictive control(MPC)based controllers are *** with the integral type,the MPC-based controller can simultaneously improve the dynamic responses and the tolerance ability under *** proposed controller is validated via an IEEE benchmark system,and the effectiveness of its application in actual power systems is verified.

关键词： Frequency control cyber attack distributed control passive fault attenuation cyber-attack-tolerant frequency control

The golden age for popularizing big data

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Science China(Information Sciences) 2016年第10期59卷 239-241页

作者： Lionel ming-shuan ni Jiang XIAO Haoyu TAN Department of Computer and Information Science the University of Macau Department of Computer Science and Engineering Hong Kong University of Science and Technology

The fast development of the Internet and Mobile Internet has opened up the era of big *** academia and industry have realized that the potential knowledge hidden in big data is huge and great business opportunities can be created by exploiting the data deeply and *** in 2000,as legacy RDBMS[1]could no longer meet the requirements of handling large volumes of data,new technologies that can provide efficient query and fast processing of big data were in urgent need.A big data technology pioneer,Google,

关键词： RDBMS The golden age for popularizing big data SQL

Design Optimization and Analysis of Exit Rotor with Diffuser Passage based on Neural Network Surrogate Model and Entropy Generation Method

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Journal of Thermal Science 2023年第2期32卷 739-752页

作者： JIN Yun GENG Shaojuan LIU Shuaipeng ni ming ZHANG Hongwu Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Innovation Academy for Light-duty Gas Turbine Chinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China

In this paper,a diffuser passage compressor design is introduced via optimization to improve the aerodynamic performance of the exit rotor in a multistage axial *** in-house design optimization platform,based on genetic algorithm and back propagation neural network surrogate model,is constructed to perform the *** optimization parameters include diffusion angle of meridian passage,diffusion length of meridian passage,change of blade camber angle and blade *** impacts of these design parameters on efficiency and stability improvement are analyzed based on the optimization *** optimized diffuser passage compressor designs are selected from the optimization solution set by comprehensively considering efficiency and stability of the rotor,and the influencing mechanisms on efficiency and stability are further *** simulation results show that the application of diffuser passage compressor design can improve the load coefficient by 12.1%and efficiency by 1.28%at the design mass flow rate condition,and the stall margin can be improved by 12.5%.According to the local entropy generation model analysis,despite the upper and lower endwall loss of the diffuser passage rotor are increased,the profile loss is reduced compared with the original *** efficiency of the diffuser passage rotor can be influenced by both loss and *** the near stall condition,decreasing flow blockage at blade root region can improve the stall margin of the diffuser passage rotor.

关键词： exit rotor diffuser passage neural network surrogate model entropy generation rate flow blockage

Distribution Locational Marginal Pricing Based Equilibrium Optimization Strategy for Data Center Park with Spatial-temporal Demand-side Resources

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1959-1970页

作者： Zhihao Yang Anupam Trivedi ming ni Haoming Liu Dipti Srinivasan IEEE College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China Department of Electrical&Computer Engineering National University of SingaporeSingapore

This paper proposes a distribution locational marginal pricing(DLMP) based bi-level Stackelberg game framework between the internet service company(ISC) and distribution system operator(DSO) in the data center park. To minimize electricity costs, the ISC at the upper level dispatches the interactive workloads(IWs) across different data center buildings spatially and schedules the battery energy storage system temporally in response to DLMP. Photovoltaic generation and static var generation provide extra active and reactive power. At the lower level, DSO calculates the DLMP by minimizing the total electricity cost under the two-part tariff policy and ensures that the distribution network is uncongested and bus voltage is within the limit. The equilibrium solution is obtained by converting the bi-level optimization into a single-level mixed-integer second-order cone programming optimization using the strong duality theorem and the binary expansion method. Case studies verify that the proposed method benefits both the DSO and ISC while preserving the privacy of the ISC. By taking into account the uncertainties in IWs and photovoltaic generation, the flexibility of distribution networks is enhanced, which further facilitates the accommodation of more demand-side resources.

关键词： Bi-level optimization congestion management data center demand response distribution locational marginal pricing(DLMP) robust optimization

The Impulsive Solution for a Semi-linear Singularly Perturbed Differential-difference Equation

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 333-342页

作者： Ai-feng WANG Mei XU ming-kang ni School of Mathematical Science Huaiyin Normal University Department of Mathematics East China Normal University

The impulsive solution for a semi-linear singularly perturbed differential-difference equation is studied. Using the methods of boundary function and fractional steps, we construct the formula asymptotic expansion of the problem. At the same time, Based on sewing techniques, the existence of the smooth impulsive solution and the uniform validity of the asymptotic expansion are proved.

关键词： singularly perturbed differential-difference equation delay argument asymptotic expansion im-pulsive solution boundary function

Plug-in and plug-out dispatch optimization in microgrid clusters based on flexible communication

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Journal of Modern Power Systems and Clean Energy 2017年第4期5卷 663-670页

作者： Jie YU ming ni Yiping JIAO Xiaolong WANG School of Electrical Engineering Southeast UniversityNanjingChina NARI Technology Co.Ltd NanjingChina School of Automation Southeast UniversityNanjingChina

With large-scale development of distributed generation(DG) and its potential role in microgrids, the microgrid cluster(MGC) becomes a useful control model to assist the integration of DG. Considering that microgrids in a MGC, power dispatch optimization in a MGC is dif-ficult to achieve. In this paper, a hybrid interactive communication optimization solution(HICOS) is suggested based on flexible communication, which could be used to solve plug-in or plug-out operation states of microgrids in MGC power dispatch optimization. HICOS consists of a hierarchical architecture: the upper layer uses distributed control among multiple microgrids, with no central controller for the MGC, and the lower layer uses a central controller for each microgrid. Based on flexible communication links among microgrids, the optimal iterative information are exchanged among microgrids, thus HICOS would gradually converge to the global optimal *** some microgrids plug-in or plug-out, communication links will be changed, so as to unsuccessfully reach optimal solution. Differing from changeless communication links in traditional communication networks, HICOS redefines the topology of flexible communication links to meet the requirement to reach the global optimal *** studies show that HICOS could effectively reach the global optimal dispatch solution with non-MGC center. Especially, facing to microgrids plug-in or plug-out states, HICOS would also reach the global optimal solution based on refined communication link topology.

关键词： Microgrid Cluster(MGC) Plug-in/plug-out dispatch optimization Hybrid interactive communication optimization solution(HICOS) Flexible communication

Plasma radiofrequency-assisted microsuction for the treatment of facial overfilled syndrome induced by diverse causes in Asians

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Chinese Journal of Plastic and Reconstructive Surgery 2024年第4期6卷 176-184页

作者： ming ni Dong Wang Beijing Yimei Medical Cosmetology Plastic Clinic Chaoyang District Jiangsu SIRRIM Plastic and Aesthetic Hospital Qinhuai District

Background: In Asia, facial overfilled syndrome(FOS) can arise from iatrogenic causes involving the excessive use of filling materials, as well as physiological causes such as adipose tissue hypertrophy type, age-related type, and lacuna type. This study aimed to demonstrate the safety and effectiveness of plasma radiofrequency-assisted microsuction(PRFAMS) for improving the appearance of FOS induced by various ***: PRFAMS was performed on 84 anatomical regions of 37 female patients(including 12 with physiological causes, 6 with hyaluronic acid causes, and 19 with fat causes), aged between 20 and 50 years(mean, 35.9 years),who had FOS. Demographic and surgical data were collected retrospectively. Preoperative and postoperative photographs were taken, and satisfaction interviews were conducted at least six months after ***: All the patients underwent successful surgery under local or intravenous anesthesia. Only four anatomic regions showed noticeable asymmetry postoperatively, requiring a secondary operation. Postoperative skin numbness, muscle paralysis, bruising, and minor contouring irregularities improved significantly within 2–3weeks of recovery. Additionally, five patients with longer edema periods demonstrated substantial improvement after more than five weeks. No cases of skin necrosis, thermal injury, or other serious complications related to the device or procedure were reported. Ultimately, all patients expressed satisfaction with their ***: The PRFAMS technique is a safe and effective method for treating FOS induced by various causes,while minimizing complications and ensuring high patient satisfaction.

关键词： Low-temperature plasma radiofrequency Aesthetic microsuction Skin tightening Facial overfilled syndrome Inducement classification

Thermal conductivity prediction of MgAl2O4:a non-equilibrium molecular dynamics calculation

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Journal of Iron and Steel Research International 2020年第5期27卷 500-505页

作者： Cheng-ming ni Hua-wei Fan Xu-dong Wang Man Yao School of Materials Science and Engineering Dalian University of TechnologyDalian 116000LiaoningChina

Magnesium aluminate spinel(MgAl2O4)is widely used in steel metallurgy *** conductivity at high temperature signifcantly infuences the cooling process of blast furnace and the heat preservation of steel *** efect of external(temperature)and internal(antisite defect and grain boundary)factors on the thermal conductivity of MgAl2O4 was studied with non-equilibrium molecular *** main factors afecting the thermal conductivity of MgAl2O4 were *** the temperature range of 100-2000 K,the results showed that the thermal conductivity of MgAl2O4 changed from 11.54 to 4.95 W/(m K)with the increase in temperature and was relatively stable at the temperature above 1000 *** thermal conductivity of MgAl2O4 declined frst and then rose with the increase in the antisite defects,and the minimum value was 6.95 W/(m K)at the inversion parameter i=*** addition,grain boundaries reduced the thermal conductivity of MgAl2O4 by 20%-30%at temperature below 1000 K comparing with the non-grain boundary *** grain boundary rotation angle at temperature above 1000 K had less efect on the thermal conductivity than that below 1000 *** simulation scheme for thermal conductivity of MgAl2O4 can also be applied to the study of other nonmetallic ceramics.

关键词： Non-equilibrium molecular dynamics Thermal conductivity Magnesium aluminate spinel Antisite defect Grain boundary