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Augmented line sampling and combination algorithm for imprecise time-variant reliability analysis

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Chinese Journal of Aeronautics 2024年第12期37卷 258-274页

作者： Xiukai YUAN Weiming ZHENG Yunfei SHU yiwei DONG School of Aerospace Engineering Xiamen UniversityXiamen 361005China

Assessment of imprecise time-variant reliability in engineering is a critical task when accounting for both the variability of structural properties and loads over time and the presence of uncertainties involved in the ambiguity of parameters *** estimate the Imprecise Time-variant Failure Probability Function(ITFPF)and derive the imprecise reliability results as a byproduct,Adaptive Combination Augmented Line Sampling(ACALS)is *** consists of three integrated features:Augmented Line Sampling(ALS),adaptive strategy,and the optimal *** is adopted as an efficient analysis tool to obtain the failure probability function *** ***,the adaptive strategy iteratively applies ALS while considering both imprecise parameters and time ***,the optimal combination algorithm collects all result components in an optimal manner to minimize the Coefficient of Variance(C.o.V.)of the ITFPF ***,the proposed ACALS method outperforms the original ALS method by efficiently estimating the ITFPF while guaranteeing a minimal ***,the proposed approach can serve as an effective tool for imprecise time-variant reliability analysis in real engineering *** examples are presented to demonstrate the superiority of the proposed approach in addressing the challenges of estimating the ITFPF.

关键词： Time-variant reliability Imprecise reliability Line sampling Adaptive strategy Combination algorithm

Deformation behavior of non-rigid airships in wind tunnel tests

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Chinese Journal of Aeronautics 2019年第3期32卷 611-618页

作者： Lingling LU Hongwei SONG yiwei WANG Chenguang HUANG Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Deformation behavior of non-rigid airships in wind tunnel tests is studied by considering three factors, including internal pressure, flow velocity and angle of attack. Fiber Bragg grating strain sensors are used to measure the deformation of non-rigid airships. Wind tunnel tests in the case of different flow velocities and angles of attack are conducted. The measurement results reveal that the airship deformation is in proportion to internal pressure. For the tensile region,the airship deformation is in proportion to flow velocity. Effects of angle of attack on structural deformation are more complicated and there is no clear relationship existing between airship deformation and angle of attack.

关键词： Angle of attack Fiber Bragg grating sensor Flow velocity Internal pressure Non-rigid airship Wind tunnel test

VR industrial applications―A singapore perspective

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Virtual Reality & Intelligent Hardware 2020年第5期2卷 409-420页

作者： Athirah SYAMIMI yiwei GONG Ryan LIEW VRcollab Pte.Ltd. 75 Ayer Rajah Crescent139953 Singapore

Virtual Reality(VR)has been around for a long time but has come into the spotlight only *** an industrial perspective,this article serves as a proverbial scalpel to dissect the different use cases and commercial applications of VR in *** researching the Singapore market,we examine how VR has *** the moment,the global annual budget for VR(and augmented reality)is at an upward trend with a leading growth in market value for the training *** in Singapore has also seen a rapid development in recent *** discuss some of the Singapore government's initiatives to promote the commercial adoption of VR for the digital economy of the *** address the mass adoption of VR,we present VRcollab's business solutions for the construction and building industry.2020 is one of the most important years for VR in history.

关键词： Virtual reality VR applications Building information modeling

Aerodynamic simulation of high-speed trains based on the Lattice Boltzmann Method (LBM)

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Science China(Technological Sciences) 2008年第6期51卷 773-783页

作者： WANG yiwei WANG Yang AN YiRan CHEN YaoSong Department of Mechanics and Engineering Peking UniversityBeijing 100871China

Aerodynamic simulation of high-speed trains has been carried out by using Lattice Boltzmann Method (LBM). Non-simplified train model was used and the number of space grids reached tens of millions. All results under d... 详细信息

关键词： Lattice Boltzmann Method (LBM) aerodynamic simulation engineering application

Suspension quality and power consumption of the complex multiphase flow field in a draft-tube stirred reactor

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Particuology 2021年第3期19卷 91-102页

作者： Licheng Wang Yanxing Tian Yu Qi yiwei Gao Mengya Wang School of Chemistry and Chemical Engineering Tianjin University of TechnologyTianjin 300384China

Experiment and simulation were used to study the flow fields of a liquid-solid-solid three-phase system in a draft-tube stirred reactor with a six-flat-bladed turbine impeller(BT)and a 45°pitched six-bladed upflow turbine impeller(PBTU45).The computational fluid dynamics(CFD)formulation was based on a 3D Eulerian multi-fluid model along with a renormalization group(RNG)k-ε turbulence model,which took into account the inter-phase momentum exchange between different *** CFD model was validated using experimental data,and the suspension quality was validated by determining the standard deviation of the solid *** solid suspension was achieved in flow fields agitated by the BT impeller at low impeller *** draft tube adversely affected solid dispersion at most impeller *** flow fields agitated by the PBTU45 impeller,good solid suspension required a faster impeller *** suspension quality with the draft tube was better than that without the draft tube under most operating *** power consumption of the BT or PBTU45 impeller with the draft tube was less than that without the draft tube at most impeller speeds.

关键词： Liquid-solid-solid Stirred reactor Draft tube Computational fluid dynamics Power consumption Suspension quality

Solar fuel production through concentrating light irradiation

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Green Energy & Environment 2024年第10期9卷 1550-1580页

作者： yiwei Fu Yi Wang Jie Huang Kejian Lu Maochang Liu International Research Center for Renewable Energy State Key Laboratory of Multiphase FlowXi'an Jiaotong UniversityXi'anShaanxi710049China Suzhou Academy of Xi'an Jiaotong University SuzhouJiangsu215123China

The climate crisis necessitates the development of non-fossil energy *** solar energy for fuel production shows promise and offers the potential to utilize existing energy ***,solar fuel production is in its early stages of development,constrained by low conversion efficiency and challenges in scaling up *** solar energy(CSE)technology has matured alongside the rapid growth of solar thermal power *** review provides an overview of current CSE methods and solar fuel production,analyzes their integration compatibility,and delves into the theoretical mechanisms by which CSE impacts solar energy conversion efficiency and product selectivity in the context of photo-electrochemistry,thermochemistry,and photo-thermal co-catalysis for solar fuel *** review also summarizes approaches to studying the photoelectric and photothermal effects of ***,it explores emerging novel CSE technology methods in the field of solar fuel production.

关键词： Concentrated solar energy Solar fuel Photo-electrochemistry Thermochemistry Photo-thermal co-catalysis

Necessary Condition for the Success of Synchronous GNSS Spoofing

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Chinese Journal of Electronics 2023年第3期32卷 438-452页

作者： WANG yiwei KOU Yanhong HUANG Zhigang School of Electronics and Information Engineering Beihang University

A synchronous GNSS generator spoofer aims at directly taking over the tracking loops of the receiver with the lowest possible spoofing to signal ratio(SSR) without forcing it to lose lock. This paper investigates the factors that affect spoofing success and their relationships. The necessary conditions for successful spoofing are obtained by deriving the code tracking error in the presence of spoofing and analyzing the effects of SSR,spoofing synchronization errors, and receiver settings on the S-curve ambiguity and code tracking trajectory. The minimum SSRs for a successful spoofing calculated from the theoretical formulation agree with Monte Carlo simulations at digital intermediate frequency signal level within 1 dB when the spoofer pulls the code phase in the same direction as the code phase synchronization error, and the required SSRs can be much lower when pulling in the opposite direction. The maximum spoofing code phase error for a successful spoofing is tested by using TEXBAT datasets, which coincides with the theoretical results within 0.1 chip. This study reveals the mechanism of covert spoofing and can play a constructive role in the future development of spoofing and anti-spoofing methods.

关键词： Global navigation satellite system Tracking loops Codes Target tracking Simulation Receivers Trajectory

Regional Sustainable Assessment at City Level Based on CSDIS(China Sustainable Development Indicator System)Concept in the New Era,China

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Chinese Geographical Science 2020年第6期30卷 976-992页

作者： WEI Jianfei DING Zhiwei MENG yiwei LI Qiang Key Laboratory of Geospatial Technology for Middle and Lower Yellow River Regions of Ministry of Education&Collaborative Innovation Center of Urban-Rural Coordinated Development of Henan Province/Key Research Institute of Yellow River Civilization and Sustainable Development&Collaborative Innovation Center on Yellow River Civilization of Henan Province Henan University^Kaifeng 475004China College of Environment and Planning Henan University^Kaifeng 475004China College of Urban Economics and Public Administration Capital University of Economics and BusinessBeijing 100070China

The core issue of sustainable development refers to the coordinated development of economic-social-environmental *** the present study,by complying with the China Sustainable Development Indicator System(CSDIS)concept,a comprehensive index system was built;besides,Natural Breaks(Jenks)Classification Method,Exploratory Spatial Data Analysis and Geographic Detector Analysis were conducted to delve into the sustainability and coordinated degree at city level in China from 2007 to *** achieved results are presented as ***,for spatial differentiation,the overall spatial distribution pattern was characterized by the high-value units in eastern China and the low-value units in western China from 2007 to *** be specific,the high-value units were radiated along the Beijing-Guangdong Axis(Jing-Guang Axis)centered on the core of Beijing-Tianjin-Hebei Region,the middle-value units were distributed in strips along the coast,and the low-value units were vastly gathered in western China and gradually break via the Hu Huanyong line(Hu Line)in south China from 2007 to *** specifically,based on the five subsystems,the pattern of each system was consistent with the whole,whereas the degree of concentration was ***,for spatial correlation,the significant High-High(HH)areas were primarily distributed in the core of Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta *** significant Low-Low(LL)areas were continuously distributed in the southwest China and broke through the Hu Line from 2007 to *** were insufficient number of significant High-Low(HL)and significant Low-High(LH)areas,whereas the spatial agglomeration of them was less ***,for internal coupling coordination,the spatial differentiation between the coupling degree and the coupling coordinated degree was significantly consistent in 2007 and *** Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta Regions have demonstrated a high lev

关键词： sustainable development level spatial differentiation city level China

A microextraction approach for rapid extraction and separation of Mn(Ⅱ) and Co(Ⅱ) using saponified D2EHPA system

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Frontiers of Chemical Science and Engineering 2022年第6期16卷 963-972页

作者： yiwei Zhou Chen Zhuo Jinpei Huang Haipeng Liu Jianhong Xu The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

In this paper,we proposed a microextraction approach for the extraction and separation of Mn(Ⅱ)and Co(Ⅱ)from sulfate solution simulating leachate of spent lithium-ion battery cathode materials using saponified di-(2-ethylhexyl)phosphoric acid *** effects of the following operational variables were investigated:equilibrium pH,tri-«-butyl phosphate concentration,saponification rate,two-phase ratio and residence *** results showcased that the microextractor can reach the extraction equilibrium within 20 s,thereby greatly reducing necessary extraction time comparing to that of conventional *** volumetric mass transfer coefficient showed 8-21 times larger than that of batch *** the help of microextractor,95%of Mn(Ⅱ)was extracted with a single theoretical stage at a chosen two-phase ratio of 3:1,and the separation factor β_(Mn/Co) was as large as *** the subsequent stripping step,more than 99%of manganese from loaded phase was easily stripped under optimal *** microextraction approach greatly enhances the mass transfer while enabling a continuous and controllable extraction process within a simple structure *** extracting spent electrode material with microextractors,the comprehensive recovery of mangenese can reach 96%.The microextraction approach has a good applicability in the spent lithium-ion battery cathode materials recycling at both bench and industrial scales.

关键词： extraction equilibrium mass transfer coeffi-cient microextraction multicomponent extraction di-(2-ethylhexyl)phosphoric acid