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Light(Science & Applications) 2015年第1期4卷 1-7页

作者： Hong-Hua Fang Feng Wang Sampson Adjokatse Ni Zhao Jacky Even maria antonietta loi Photophysics&OptoElectronics Zernike Institute for Advanced MaterialsNijenborgh 4Groningen 9747 AGThe Netherlands Department of Electronic Engineering The Chinese University of Hong KongNew TerritoriesHong Kong UniversitéEuropéenne de Bretagne INSAFOTONUMR 608235708 RennesFrance

Formamidinium lead iodide(FAPbI3)is a newly developed hybrid perovskite that potentially can be used in high-efficiency solution-processed solar ***,the temperature-dependent dynamic optical properties of three types of FAPbI3 perovskite films(fabricated using three different precursor systems)are comparatively *** time-resolved photoluminescence(PL)spectra reveal that FAPbI3 films made from the new precursor(a mixture of formamidinium iodide and hydrogen lead triiodide)exhibit the longest lifetime of 439 ns at room temperature,suggesting a lower number of defects and lower non-radiative recombination losses compared with FAPbI3 obtained from the other two *** the temperature-dependent PL spectra,a phase transition in the films is clearly ***,exciton-binding energies of 8.1 and 18 meV for the high-and lowtemperature phases are extracted,***,the PL spectra for all of the samples show a single peak at room temperature,whereas at liquid-helium temperature the emission features two peaks:one in higher energy displaying a fast decay(0.5 ns)and a second red-shifted peak with a decay of up to several *** two emissions,separated by~18 meV,are attributed to free excitons and bound excitons with singlet and triplet characters,respectively.

关键词： formamidinium lead iodide low temperature perovskite photoluminescence triplet exciton

Robust N−k Security-constrained Optimal Power Flow Incorporating Preventive and Corrective Generation Dispatch to Improve Power System Reliability

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 351-364页

作者： Liping Huang Chun Sing Lai Zhuoli Zhao Guangya Yang Bang Zhong loi Lei Lai School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Automation Guangdong University of TechnologyGuangzhou 510006Chinaand also with the Department of Electronic and Electrical EngineeringBrunel University LondonLondonUB83PHUK Center for Electric Power System and Energy Department of Electrical EngineeringTechnical University of DenmarkKongens Lyngby 2800Demark Zhaoqing Power Supply Bureau Guangdong Power Grid CompanyChina Southern Power GridZhaoqing 526020China

As extreme weather events have become more frequent in recent years,improving the resilience and reliability of power systems has become an important area of *** this paper,a robust preventive-corrective security-constrained optimal power flow(RO-PCSCOPF)model is proposed to improve power system reliability under N−k *** the short-term emergency limit(STL)and the long-term operating limit(LTL)of the post-contingency power flow on the branch are *** with the existing robust corrective SCOPF model that only considers STL or LTL,the proposed ROPCSCOPF model can achieve a more reliable generation dispatch *** addition,this paper also summarizes and compares the solution methods for solving the N−k SCOPF *** computational efficiency of the classical Benders decomposition(BD)method,robust optimization(RO)method,and line outage distribution factor(LODF)method are investigated on the IEEE 24-bus Reliability Test System and 118-bus *** results show that the BD method has the worst computation *** RO method and the LODF method have comparable ***,the LODF method can only be used for the preventive SCOPF and not for the corrective *** RO method can be used for both.

关键词： Benders cut bender decomposition line outage distribution factor N−k security criterion optimal power flow power system reliability resilience robust optimization

Application of machine learning technique for predicting and evaluating chloride ingress in concrete

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Frontiers of Structural and Civil Engineering 2022年第9期16卷 1153-1169页

作者： Van Quan TRAN Van loi GIAP Dinh Phien VU Riya Catherine GEORGE Lanh Si HO Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

The degradation of concrete structure in the marine environment is often related to chloride-induced corrosion of reinforcement ***,the chloride concentration in concrete is a vital parameter for estimating the corrosion level of reinforcement *** research aims at predicting the chloride content in concrete using three hybrid models of gradient boosting(GB),artificial neural network(ANN),and random forest(RF)in combination with particle swarm optimization(PSO).The input variables for modeling include exposure condition,water/binder ratio(W/B),cement content,silica fume,time exposure,and depth of *** results indicate that three models performed well with high accuracy of prediction(R2⩾0.90).Among three hybrid models,the model using GB_PSO achieved the highest prediction accuracy(R2=0.9551,RMSE=0.0327,and MAE=0.0181).Based on the results of sensitivity analysis using SHapley Additive exPlanation(SHAP)and partial dependence plots 1D(PDP-1D),it was found that the exposure condition and depth of measurement were the two most vital variables affecting the prediction of chloride *** the number of different exposure conditions is larger than two,the exposure significantly impacted the chloride content of concrete because the chloride ion ingress is affected by both chemical and physical *** study provides an insight into the evaluation and prediction of the chloride content of concrete in the marine environment.

关键词： gradient boosting random forest chloride content concrete sensitivity analysis

一种分体积木和功能分层式结构的多适应型纹影系统研制及应用

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自动化与仪器仪表 2024年第6期 296-300页

作者：黄昊宇凌忠伟刘为杰夏语中国空气动力研究与发展中心高速所四川绵阳621000

2 m×2 m高速自由射流风洞纹影系统具有仪器光轴位置高焦距长、多测量工位移动范围宽、多部件协同控制环节多、试验过程振动大、现场设备有干涉等特点,为了满足其可靠性、维护性、安全性、抗振性的设计要求,项目有针对性地创新发展了主... 详细信息

2 m×2 m高速自由射流风洞纹影系统具有仪器光轴位置高焦距长、多测量工位移动范围宽、多部件协同控制环节多、试验过程振动大、现场设备有干涉等特点,为了满足其可靠性、维护性、安全性、抗振性的设计要求,项目有针对性地创新发展了主反射镜装调形式、功能分层结构、多维手动/电动相结合的调节方式、定位减振方法,克服了高精度研磨、多光学部件耦合、装配应力影响大等困难,建立了一套Φ800 mm口径分体积木和功能分层式结构的多适应型纹影系统。该纹影系统通过多轮静动态试验验证和应用,从试验结果可以看出,该大型纹影系统运行稳定可靠,成像效果良好,纹影视频画面清晰,无明显条纹和阴影;系统功能完善,电控+手动的多自由度光路调节方式使用便捷,定位精准;图像采集软件自动化程度高,系统具有较高的普适性,可满足2米×2米高速自由射流风洞大部分试验任务需要。

关键词：高超声速风洞分体积木多适应型纹影系统

Operation Cost Optimization Method of Regional Integrated Energy System in Electricity Market Environment Considering Uncertainty

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 368-380页

作者： Peng Li Fan Zhang Xiyuan Ma Senjing Yao Yuhang Wu Ping Yang Zhuoli Zhao loi Lei Lai Digital Grid Research Institute of China Southern Power Grid Guangzhou 510663China Guangdong Key Laboratory of Clean Energy Technology South China University of TechnologyGuangzhou 510640China Department of Electrical Engineering School of AutomationGuangdong University of TechnologyGuangzhou 510006China IEEE

In the electricity market environment,the regional integrated energy system(RIES)can reduce the total operation cost by participating in electricity market ***,the RIES will face the risk of load and electricity price uncertainties,which may make its operation cost higher than *** paper proposes a method to optimize the operation cost of the RIES in the electricity market environment considering ***,based on the operation cost structure of the RIES in the electricity market environment,the energy flow relationship of the RIES is analyzed,and the operation cost model of the RIES is ***,the electricity purchase costs of the RIES in the medium-and long-term electricity markets,the spot electricity market,and the retail electricity market are ***,considering the risk of load and electricity price uncertainties,the operation cost optimization model of the RIES is established based on conditional *** it is solved to obtain the operation cost optimization strategy of the *** results show that the proposed operation cost optimization method can reduce the operation cost of high electricity price scenario by optimizing the energy purchase and distribution strategy,constrain the risk of load and electricity price uncertainties,and help balance the risks and benefits.

关键词： Conditional value-at-risk electricity market uncertainty operation cost regional integrated energy system(RIES).

Modeling,Oscillation Analysis and Distributed Stabilization Control of Autonomous PV-based Microgrids

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 921-936页

作者： Zhuoli Zhao Jindian Xie Shaoqing Gong Xi Luo Yuewu Wang Chun Sing Lai Ping Yang loi Lei Lai Josep M.Guerrero Department of Electrical Engineering School of AutomationGuangdong University of TechnologyGuangzhou 510006China School of Automation Guangxi University of Science and TechnologyLiuzhou 545006China Department of Electronic and Electrical Engineering Brunel University LondonLondon UB83PHUK Key Laboratory of Clean Energy Technology of Guangdong Province South China University of TechnologyGuangzhou 510640China Department of Energy Technology Aalborg University9220 AalborgDenmark

Driven by rising energy demand and the goal of carbon neutrality,renewable energy generations(REGs),especially photovoltaic(PV)generations,are widely used in the urban power energy *** the intelligent control of microgrids(MG)brings economic and efficient operation,its potential stability problem cannot be *** date,most of the research on modeling,analyzing and enhancing the stability of MG usually assume the DC-link as an ideal voltage ***,this practice of ignoring the dynamics of DC-link may omit the latent oscillation phenomena of autonomous PV-based ***,this paper establishes a complete dynamic model of autonomous PV-based MG including PV panels and *** from previous conclusions of idealizing DC-link dynamics,participation factor analysis finds the potential impact of DClink dynamics on system dynamic performance,and different influence factors including critical control parameters and nonlinear V-I output characteristic of PV array are considered to further reveal oscillation ***,based on the average consensus algorithm,a distributed stabilization controller with strong robustness is proposed to enhance stability of the PVbased MG,which does not affect the steady-state performance of the ***,the correctness of all theoretical analysis and the effectiveness of the proposed controller are verified by time domain simulation and hardware-in-loop tests.

关键词： Average consensus algorithm distributed stabilization microgrid oscillation photovoltaic(PV)generation stability analysis

胃内球囊术治疗不同体质量指数肥胖症的短期临床疗效

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中华消化外科杂志 2022年第12期21卷 1573-1578页

作者： Daniel Liu Qiuye Cheng Sam Alhayo Mark Magdy Ken loi 新南威尔士大学圣乔治私立医院上消化道和减重外科悉尼2217

目的探讨胃内球囊术治疗不同体质量指数(BMI)肥胖症的短期临床疗效。方法采用回顾性描述性研究方法。收集2017年1月至2021年12月3家医学中心收治的62例(赫斯特维尔私立医院56例、新南威尔士大学圣乔治私立医院4例、东悉尼私立医院2例)不... 详细信息

目的探讨胃内球囊术治疗不同体质量指数(BMI)肥胖症的短期临床疗效。方法采用回顾性描述性研究方法。收集2017年1月至2021年12月3家医学中心收治的62例(赫斯特维尔私立医院56例、新南威尔士大学圣乔治私立医院4例、东悉尼私立医院2例)不同BMI肥胖症行胃内球囊术患者的临床资料;男15例,女47例;年龄为45.1(18.0~67.0)岁;BMI为35.1(27.8~48.4)kg/m^(2)。62例患者中,27 kg/m^(2)≤BMI<35 kg/m^(2)33例,BMI≥35 kg/m^(2)29例。观察指标:(1)首次手术及术后并发症情况。(2)首次术后随访情况。(3)再次行胃内球囊术及术后并发症情况。(4)再次行胃内球囊术后随访情况。采用门诊方式进行随访。患者于术后1、3、6个月进行随访,了解术后并发症发生情况及减重效果。正态分布的计量资料以x±s表示,偏态分布的计量资料以M(范围)表示。计数资料以绝对数表示。结果(1)首次手术及术后并发症情况。62例肥胖症患者均顺利施行首次胃内球囊术。62例患者中,45例发生术后并发症,包括胃食管反流38例,吞咽困难或打嗝12例,上腹部疼痛9例,恶心呕吐4例,同一例患者可合并多种并发症。33例27 kg/m^(2)≤BMI<35 kg/m^(2)患者和29例BMI≥35 kg/m^(2)患者发生上述并发症分别为21、8、7、2例和17、4、2、2例。(2)首次胃内球囊术后随访情况。62例肥胖症患者中,完成术后1、3、6个月随访分别为52、46、38例,其中27 kg/m^(2)≤BMI<35 kg/m^(2)和BMI≥35 kg/m^(2)分别为30、25、20例和22、21、18例。62例患者中,选择提前取出胃内球囊15例,包括因持续恶心呕吐7例,对短期减重效果不满意6例,急性上腹部疼痛、妊娠各1例。30例27 kg/m^(2)≤BMI<35 kg/m^(2)患者和22例BMI≥35 kg/m^(2)患者术后1个月体质量下降分别为(4.8±3.0)kg和(6.6±2.8)kg;25例27 kg/m^(2)≤BMI<35 kg/m^(2)患者和21例BMI≥35 kg/m^(2)患者术后3个月体质量下降分别为(6.7±4.4)kg和(10.6±4.8)kg;20例27 kg/m^(2)≤BMI<35 kg/m^(2)患者和18例BMI≥35 kg/m^(2)患者术后6个月体质量下降分别为(8.5±4.8)kg和(9.8±3.9)kg,多余体质量减轻百分比分别为53%±26%和29%±15%,总体质量减轻率分别为14%±5%和10%±5%。(3)再次行胃内球囊术及术后并发症情况。完成首次术后6个月随访的38例肥胖症患者中,9例27 kg/m^(2)≤BMI<35 kg/m^(2)和7例BMI≥35 kg/m^(2)患者选择取出首次胃内球囊后立即再次行胃内球囊术,再次手术后发生胃食管反流、吞咽困难或打嗝、上腹部疼痛、恶心呕吐分别为4、3、0、0例和4、0、2、1例。(4)再次行胃内球囊术后随访情况。16例选择再次行胃内球囊术患者均完成术后6个月随访,无患者提前取出胃内球囊。9例27 kg/m^(2)≤BMI<35 kg/m^(2)患者和7例BMI≥35 kg/m^(2)患者术后6个月体质量下降分别为(8.8±8.5)kg和(18.9±9.7)kg,多余体质量减轻百分比分别为44%±38%和41%±15%。结论胃内球囊术应用于BMI≥27 kg/m^(2)肥胖症患者可获得较好短期减重效果,胃食管反流、吞咽困难或打嗝、上腹部疼痛、恶心呕吐是术后常见并发症。

关键词：肥胖症减重代谢外科减重手术胃内球囊疗效

Transactive Energy Trading in Reconfigurable Multi-carrier Energy Systems

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 67-76页

作者： Yifei Wang Zhiheng Huang Zhenhao Li Xi Wu loi Lei Lai Fangyuan Xu School of Automation Guangdong University of TechnologyGuangzhouChina School of Electrical Engineering Southeast UniversityNanjingChina

The penetration of multi-carrier energy systems in distribution system gains more and more *** this paper,a bi-level transactive energy trading framework is proposed to improve the energy scheduling and operation efficiency for multi-carrier energy systems which are modeled as energy hubs(EHs).In the upper level,each EH in the distribution system not only makes energy scheduling decisions considering supplies and demands of local energy,but also trades energy with each other to further maximize their social *** associated trading payment among EHs is made in a fair manner by applying Nash bargaining *** solve the bargaining problem by decomposing it into two subproblems:operation cost minimization problem and payment bargaining ***,based on the trading decision,the nodal equivalent loads of EHs are sent to the distribution system operator(DSO)without publishing trading *** applying the second-order cone programming(SOCP),DSO reconfigures the network to reduce the transmission loss of the system in the lower *** network reconfiguration and the trading behavior of EHs interact and iterate until the *** studies on modified IEEE 33-bus distribution system demonstrate the effectiveness of the proposed framework.

关键词： Multi-carrier energy system energy hub(EH) transactive energy distribution reconfiguration Nash bargaining

Optimal design theories of tuned mass dampers with nonlinear viscous damping

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Earthquake Engineering and Engineering Vibration 2009年第4期8卷 547-560页

作者： Lap-loi Chung Lai-Yun Wu Hsu-Hui Huang Chung-Hsin Chang Kuan-Hua Lien Center for Research on Earthquake Engineering （NCREE） Chinese Taipei Department of Civil Engineering Taiwan University. Chinese Taipei

Optimal design theory for linear tuned mass dampers （TMD） has been thoroughly investigated, but is still under development for nonlinear TMDs. In this paper, optimization procedures in the time domain are proposed for design of a TMD with nonlinear viscous damping. A dynamic analysis of a structure implemented with a nonlinear TMD is conducted first. Optimum design parameters for the nonlinear TMD are searched using an optimization method to minimize the performance index. The feasibility of the proposed optimization method is illustrated numerically by using the Taipei 101 structure implemented with TMD. The sensitivity analysis shows that the performance index is less sensitive to the damping coefficient than to the frequency ratio. Time history analysis is conducted using the Taipei 101 structure implemented with different TMDs under wind excitation. For both linear and nonlinear TMDs, the comfort requirements for building occupants are satisfied as long as the TMD is properly designed. It was found that as the damping exponent increases, the relative displacement of the TMD decreases but the damping force increases.

关键词： optimal design theory tuned mass damper (TMD) nonlinear performance index sensitivity analysis Taipei 101

Effect of land use change on water discharge in Srepok watershed,Central Highland,Viet Nam

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International Soil and Water Conservation Research 2014年第3期2卷 74-86页

作者： Nguyen Thi Ngoc Quyen Nguyen Duy Liem Nguyen Kim loi Tay Nguyen University Viet Nam.567 Le Duan streetBuon Ma Thuot CityDak Lak Province Nong Lam University Viet Nam.Linh Trung WardThu Duc districtHo Chi Minh City

Srepok watershed plays an important role in Central Highland in Viet *** impacts to developing social-economic ***,it is necessary to research elements which impact to natural resources in this *** Soil and Water Assessment Tool(SWAT)model and Geography Information System(GIS)were used to simulate water discharge in the Srepok *** objectives of the research were to apply GIS and SWAT model for simulation water discharge and then,we assessed land use change which impacted on water discharge in the *** observed stream flow data from Ban Don Stream gauge station was used to calibrate for the period from 1981 to 2000 and then validate for the period from 2001 to *** using SWAT-CUP software to calibration,NSI reached 0.63 and R square value achieved 0.64 from 2004 to 2008 in calibration and NSI gained good level at 0.74 and R square got 0.75 from 2009 to 2012 in validation step at Ban Don *** that,land cover in 2010 was processed like land cover in 2000 and set up SWAT model *** simulated water discharge in scenario 1(land use 2000)was compared with scenario 2(land use 2010),the simulation result was not significant difference between two scenarios because the change of area of land use was not much enough to affect the fluctuation of water ***,the effect of land cover on water resource could be seen clearly via total water *** percentage of surface flow in 2000 was twice times more than in 2010;retard and base flow in 2000 was slightly more than in ***,decreased surface flow,increased infiltration capacity of water and enriched base flow resulted in the growth of land cover.

关键词： Water discharge Land use change GIS SWAT model Simulations