检索结果-南通市图书馆

Intermittent Availability and its co.putation Model for Multiple Identical Units System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Intermittent Availability and its Computation Model for Mult...

Multi-objective optimal design for AC filters in high voltage direct current system based on improved multi-objective evolutionary algorithm based on deco.position

第25届中国控制与决策会议

作者： Ling Wang Jinjin Wu Xiai Chen co.gying Li Wenbo Na co.lege of Mechanical and electrical engineering China Jiliang University Department of Safety Defense Zhejiang Police Vocational Academy zhejiang Public Information Industry co. Ltd Department of Information Communication

ISBN: (纸本)9781467355339

This paper proposes the co.cept of intermittent availability for Multiple Identical Units Systems （MIUS） after analyzing the disadvantages of the existing availability theories. The analytical definition of intermittent availability is described, and the co.notation and application co.ditions of intermittent availability are also discussed in detail. In the case study, the expected values of intermittent availability for a MIUS are predicted by Monte Carlo simulation. The proposed intermittent availability theory is applicable to MIUS working intermittently with periodic maintenance time windows.

关键词： Multiple Identical Units System, Intermittent Availability, Application co.ditions, Calculation Model Monte Carlo Simulation

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

High Voltage 2023年第3期8卷 492-503页

作者： Fan Shi Honghua Wang Tianhang Lu Jiawei Huang Chengliang Wang co.lege of Energy and electrical engineering Hohai UniversityNanjingJiangsuChina Jiangsu Frontier Electric Technology co. LtdNanjingJiangsuChina

A triple-objective optimal design method for AC filters in high voltage direct current(HVDC)system based on an improved multi-objective evolutionary algorithm based on deco.position(MOEA/D)is proposed.A triple-objective optimisation mathematical model including total harmonic distortion(THD)on AC side voltage,investment co.t of AC filters and telephone harmonic form factor(THFF)is *** improved MOEA/D is proposed to realise the triple-objective optimal design for AC filters more *** improved MOEA/D adds a particular mutation operator,which can not only to prevent MOEA/D from getting stuck at local optimum but also accelerate the co.vergence to the optimum solution while the algorithm approaches the neighbourhood of the optimum solution.A three-dimensional fuzzy evaluation system is designed to select the optimum solution of the triple-objective optimisation.A case of±500 kV HVDC system is *** the±500 kV HVDC system as the prototype system,a dynamic simulation experimental platform of the rectification system of the direct current transmission system with AC filters is designed and established based on the similarity *** the simulation and experimental results verify that the proposed method have excellent performance.

关键词： MOEA/D system optimal

Exploiting demand-side heterogeneous flexible resources in risk management of power system frequency

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第5期67卷 1612-1627页

作者： YAO Yu SONG YongHua YE ChengJin DING Yi ZHAO YuMing co.lege of electrical engineering Zhejiang UniversityHangzhou310027China State Key Laboratory of Internet of Things for Smart City University of MacaoMacao SAR519000China Shenzhen Power Supply Bureau co. Ltd.Shenzhen518051China

More demand-side flexible resources(DFRs)are participating in the frequency regulation of renewable power systems,whose heterogeneous characteristics have a significant impact on the system frequency ***,selecting suitable DFRs poses a formidable challenge for independent system operators(ISO).In this paper,a reserve allocation methodology for heterogeneous DFRs is proposed to manage the risk of power system ***,a performance curve is developed to describe the co.t,capacity,and response speed of ***,a clustering method for multiple distributed DFRs is co.ducted to calculate the aggregated performance curves and uncertainty ***,the frequency security criterion co.sidering DFRs’performance is co.structed,whose linearity makes it can be easily co.pled into the system scheduling model and ***,a risk management model for DFRs co.sidering frequency-chance-co.straint is proposed to make a trade-off between co.t and frequency ***,the model is transformed into mixed integer seco.d-order co.e programming(MISOCP)and solved by the co.mercial *** proposed model is validated by the IEEE 30 and IEEE 118 bus systems.

关键词： demand-side heterogenous flexible resources risk management of power system frequency performance curve aggregation method mixed integer seco.d-order co.e programming

A nonprofiled side-channel analysis based on variational lower bound related to mutual information

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2023年第1期66卷 277-295页

作者： Chi ZHANG Xiangjun LU Pei CAO Dawu GU Zheng GUO Sen XU School of Electronic Information and electrical engineering Shanghai Jiao Tong University Zhi Xun Crypto Testing and Evaluation Technology co. Ltd. 3. Viewsource Information Science and Technology Co. Ltd.

In this paper, we attempt to improve the practical performance of the nonprofiled side-channel analysis(Non SCA) with the help of neural networks. We first derive a variational lower bound related to mutual information(VLBRMI) optimized for the co.text of Non SCA, which possesses a set of adjustable parameters and whose maximum value linearly depends on the mutual information. Then, we propose a new Non SCA method called neural mutual information analysis(NMIA) that exploits the maximum VLBRMI as the distinguisher. We present an estimator of the maximum VLBRMI, which uses neural networks to instantiate the VLBRMI and trains the neural networks to approximate the maximum VLBRMI so that we can implement the NMIA efficiently. Finally, we evaluate the NMIA on several datasets. The experimental results show that NMIA outperforms the co.relation power analysis, the mutual information analysis(MIA)based on histograms, the MIA based on kernel density estimation, and the state-of-the-art Non SCA method based on neural networks.

关键词： side-channel analysis nonprofiled method variational lower bound mutual information neural networks

A novel multi-slice electromagnetic field-circuit co.pling method for transient co.putation of long-distance gas-insulated transmission lines

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2024年第4期9卷 826-838页

作者： Shucan Cheng Yanpu Zhao Kejia Xie Bin Hu School of electrical engineering and Automation Wuhan UniversityWuhanChina Shandong Taikai High Voltage Switchgear co. Ltd.TaianChina

Accurate calculation of short-circuit electromagnetic force is crucial for both mechanical strength check and the optimal design of gas-insulated transmission lines(GIL).Since the full 3D numerical simulation method is highly time-co.suming,a novel lightweight 2D multi-slice electromagnetic field-circuit co.pled method for co.puting transient electromagnetic force is proposed,where appropriate port voltage degrees of freedom(DoFs)are introduced for the solid GIL co.ductor *** the transient magnetic field equations are co.bined with the co.straint equations of circuit part,including nodal voltage and loop current DoFs,a direct field-circuit co.pling scheme is thus *** proposed method can simultaneously co.sider the effect of interphaseshunts and ground wires,as well as the skin effect and proximity *** can accurately capture the transient electromagnetic characteristics of GIL spanning from several to tens of kilometers under different short-circuit *** transient electromagnetic forces,as well as the induced voltages and currents of the enclosure,are analysed by the proposed method for both single-phase and three-phase enclosed GIL under various short-circuit *** proposed method has the advantages of high accuracy and lightweight co.putational co.t,and thus it is also suitable for co.ducting important simulation tasks such as mechanical strength checks during the design optimisation phase of long-distance GIL.

关键词： transient co.pling field

Mechanism Design for Ancillary Service Market co.sidering Social Welfare and Fairness

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第3期10卷 1000-1010页

作者： Zhi Wu Yuanxi Wu Wei Gu Zheng Xu Shu Zheng Jingtao Zhao School of electrical engineering Southeast UniversityNanjing 210096China NARI Technology co. Ltd.Nanjing 211106China IEEE CSEE

Increasing penetration of distributed energy resources in the distribution network(DN)is threatening safe operation of the DN,which necessitates setup of the ancillary service market in the *** the ancillary service market,distribution system operator(DSO)is responsible for safety of the DN by procuring available capacities of *** existing studies,this paper proposes a novel market mechanism co.posed of two parts:choice rule and payment *** proposed choice rule simultaneously co.siders social welfare and fairness,enco.raging risk-averse aggregators to participate in the ancillary service *** is then formulated as a linear programming problem,and a distributed solution using the multi-cut Benders deco.position is ***,successful implementation of the choice rule depends on each aggregator’s truthful adoption of private ***,a payment rule is also designed,which is proved to possess two properties:incentive co.patibility and individual *** results demonstrate effectiveness of the proposed choice rule on improving fairness and verify properties of the payment rule.

关键词： Aggregator ancillary service market distributed mechanism fairness mechanism design

Characterization of wet microalgal cells pretreated with steam for lipid extraction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical engineering 2021年第9期34卷 114-120页

作者： Wenlu Song Rui Huang Hao Guo Chunguang Yin Chuanling Wang Jun Cheng Weijuan Yang Department of Life Science and engineering Jining UniversityJining 273155China The electrical engineering co.lege Guizhou UniversityGuiyang 550025China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China ShanDong Fanpu Analytic co. LtdJining 272000China

Steam pretreatment was employed to disrupt Microalgal cells for lipids *** of steam pretreatment on microstructure of microalgal cells were investigated through scanning electron microsco.y(SEM)and transmission electron microsco.y(TEM).Effect of treatment on lipid extraction was also *** cell walls were distorted after steam pretreatment due to the hydrolysis of organic macromolecules co.tained in cell *** curvature was increased from 1.88×10^(-6) m^(-1) to 1.43×10^(-7) m^(-1) after treatment with the steam at 130℃.The fractal dimension of microalgal cells increased from 1.25 to 1.30 after pretreatment for 15 min,and further increased to 1.47 when the pretreatment time was increased to 60 *** steam pretreatment temperature and time enhanced the hydrolysis of organic macromolecules,and finally destroyed microalgal cell walls at pretreatment temperature of 130℃and pretreatment time of 60 *** extracted from wet microalgal was significantly increased(2.1-fold)after pretreatment.

关键词： Chlorella pyrenoidosa Steam pretreatment Cell wall disruption Lipids extraction

A Novel Model of Failure Rate Prediction for Circular electrical co.nectors

在线全文

学校读者我要写书评

暂无评论

Journal of Shanghai Jiaotong university(Science) 2015年第4期20卷 472-476页

作者：孙博叶田园方园 School of Reliability and Systems engineering Beihang University China Aviation Optical-electrical Technology co.

The reliability of electrical co.nectors has critical impact on electronic systems. It is usually characterized by failure rate prediction value acco.ding to standard MIL-HDBK-217(or GJB-299 C in Chinese) in engineering practice. Given to their limitations and mislead results, a new failure rate prediction models needs to be presented. The presented model aims at the mechanism of increase of film thickness which leads to the increase of co.tact resistance. The estimated failure rate value can be given at different environmental co.ditions,and some of the factors affecting the reliability are taken into acco.nt. Accelerated degradation test(ADT) was co.ducted on GJB599 III series electrical co.nector. The failure rate prediction model can be simply formed and co.venient to calculate the expression of failure rate changing with time at various temperature and vibration co.ditions. This model gives an objective assessment in short time, which makes it co.venient to be applied to the engineering.

关键词： electrical co.nector failure rate prediction reliability accelerated degradation

Structure optimization of co.nection frames based on frequency sensitivity in macro-micro motion platforms

在线全文

学校读者我要写书评

暂无评论

Nanotechnology and Precision engineering 2019年第1期2卷 40-47页

作者： Lufan Zhang Xueli Li Haihong Zhang Haixin Li Hu Li Jun Wu School of Mechanical and electrical engineering Henan University of Technology Weihua Group co. Ltd. School of Mechanical and Electronic engineering Zhongyuan University of Technology

High-performance co.nection frames are of great significance for ultra-high acceleration and ultra-precision positioning in macro-micro motion platforms. This paper first takes the co.nection frame as a research object,builds a finite element model(FEM) of the natural frequency of the frame, and then verifies the co.rectness of this model. The frequency sensitivity method is then used to perturb the structural parameters of the FEM of the co.nection frame, and the sensitivities of the first-order natural frequency and mass of the co.responding structural parameters are obtained by calculation and analysis. The design variables are also determined. The natural frequency is used as the optimization objective, and the design parameters and mass of the co.nection frame are co.strained. The structural parameters of the co.necting frame are obtained through optimization, and the model is built and verified by experiments. The results show that the first-order natural frequency of the co.necting frame is effectively improved by the frequency sensitivity method, avoids resonance between the co.necting frame and the voice co.l motor, and realizes the lightweight design of the co.nection frame. This research provides a reliable basis for the stable operation and ultra-precision positioning of ultra-high acceleration macro-motion platforms.

关键词： Ultra-high acceleration co.nection frame Natural frequency Sensitivity Structure optimization