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A remote sensing system of vehicle emissions based on tunable diode laser technology

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Journal of Environmental Sciences 2006年第1期18卷 154-157页

作者： ZENG Jun GUO Hua-fang HU yue-ming College of Automation Science and Engineering South China University of Technology Guangzhou 510640 China

As being an effective real-time method of monitoring vehicle emissions on-road, a remote sensing system based on the tunable diode laser （TDL） technology was presented, and the key technologies were discussed. A field test in Guangzhou（Guangdong, China） was performed and was found that the factors, such as slope, instantaneous speed and acceleration, had significant influence on the detectable rate of the system. Based on the results, the proposal choice of testing site was presented.

关键词： remote sensing tunable diode laser vehicle emission detectable rate

Artificial neural network model for identifying taxi gross emitter from remote sensing data of vehicle emission

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Journal of Environmental Sciences 2007年第4期19卷 427-431页

作者： ZENG Jun GUO Hua-fang HU yue-ming College of Automation Science and Engineering South China University of Technology Guangzhou 510640 China. Automation Engineering Research and Manufacture Center Guangdong Academy of Sciences Guangzhou 510070 China

Vehicle emission has been the major source of air pollution in urban areas in the past two decades. This article proposes an artificial neural network model for identifying the taxi gross emitters based on the remote sensing data. After carrying out the field test in Guangzhou and analyzing various factors from the emission data, the artificial neural network modeling was proved to be an advisable method of identifying the gross emitters. On the basis of the principal component analysis and the selection of algorithm and architecture, the Back-Propagation neural network model with 8-17-1 architecture was established as the optimal approach for this purpose. It gave a percentage of hits of 93%. Our previous research result and the result from aggression analysis were compared, and they provided respectively the percentage of hits of 81.63% and 75%. This comparison demonstrates the potentiality and validity of the proposed method in the identification of taxi gross emitters.

关键词： vehicle emission remote sensing neural network principal component analysis regression analysis

Maternal mental health and well-being during the COVID-19 pandemic in Beijing, China

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World Journal of Pediatrics 2021年第3期17卷 280-289页

作者： Zhuang Wei ming-yue Gao Mary Fewtrell Jonathan Wells Jin-yue Yu Department of Child Healthcare Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Population Policy and Practice Research and Teaching DepartmentUCL Great Ormond Street Institute of Child Health30 Guilford StreetLondon WC1N 1EHUK

Background The aim of this study is to evaluate the impact of the coronavirus disease 2019(COVID-19)pandemic on breastfeeding women and to identify predictors of maternal mental health and *** Mothers aged≥18 years with a breast-fed infant≤18 months of age during the COVID-19 pandemic in Beijing,China,completed a *** analysis of lockdown consequences was performed and predictors of these outcomes were examined using stepwise linear *** Of 2233 participants,29.9%,20.0%and 34.7%felt down,lonely,and worried,respectively,during the lockdown;however,85.3%felt able to *** maternal mental health was predicted by maternal(younger age,higher education)and infant(older age,lower gestation)characteristics,and social circumstances(husband unemployed or working from home,receiving advice from family,having enough space for the baby,living close to a park or green space).Conversely,better maternal mental health was predicted by higher income,employment requiring higher qualifications,more personal space at home,shopping or walking>once/week and lack of impact of COVID-19 on job or *** with higher education,more bedrooms,fair division of household chores and attending an online mother and baby group>once/week reported better *** The findings highlight maternal characteristics and circumstances that predict poorer mental health and reduced coping which could be used to target interventions in any future public health emergencies requiring social restrictions.

关键词： Coping Coronavirus disease 2019 Maternal health Mental health Postpartum

Two new C-glucoside oxanthrones from Rumex gmelini

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Chinese Chemical Letters 2009年第7期20卷 839-841页

作者： Zhen yue Wang Hai Peng Zhao yue ming Zuo Zong Quan Wang Xian ming Tang Graduate School of Heilongjiang University of Traditional Chinese Medicine Harbin 150040 China Lunan Pharmaceutical Group Corporation Linyi 276005 China Jiangxi University of Traditional Chinese Medicine Nanchang 330004 China Yiling Pharmaceutical Group Corporation Shijiazhuang 050035 China Harbin Food and Drug Administration Harbin 150016 China

Two new C-glucoside oxanthrones, 6-methoxyl-10-hydroxyaloin A （1） and 6-methoxyl-10-hydroxyaloin B （2）, were isolated from the roots of Rumex gmelini Turcz. Their structures were elucidated on the basis of spectroscopic techniques and chemical means C 2009 Zhen yue Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Rumex gmelini Turcz. C-glucosidc oxanthrones 6-Methoxyl-10-hydroxyaloin A 6-Methoxyl-10-hydroxyaloin B

Numerical simulation of single roller melt spinning for NdFeB alloy based on finite element method

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Rare Metals 2020年第10期39卷 1145-1150页

作者： Xu-Chao Wang ming yue Dong-Tao Zhang Wei-Qiang Liu ming-Gang Zhu College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124.China Central Iron and Steel Research Institute Beijing 100081China

The numerical simulation model of single roller melt spinning for rapid quenching process of NdFeB alloy was built,and the vacuum chamber,cooling roller and sample were taken into account as a *** existing mature technology was in order to verify the correctness of *** rapid quenching ribbons with different roll speeds were used as the simulation *** results of the numerical simulation and experiments show that the validity of the model has been testified and the reasons of the formation of complete quenching ribbons and by-product have been *** experimental thickness of the ribbons is proportional to the theoretical *** the same spray condition,with the roll speed increasing,the thickness decreases *** the speed range of25-30 m·s^(-1),the simulated calculation date is close to the experimental date,which can be considered as an ideal technological parameter.

关键词： NdFeB Melt spinning Finite element method Numerical simulation

Short-process recycling of Nd-Fe-B sintered magnet sludge wastes:Challenges and approaches

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Journal of Rare Earths 2023年第10期41卷 1467-1477,I0001页

作者： Liying Cong Lichao Yu Quangui Zhou Qingmei Lu ming yue Key Lab of Advanced Functional Materials Ministry of EducationFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing100124China

Nd-Fe-B sintered magnet sludge wastes are one kind of typical commodity of recyclable rare-earth permanent magnet resources,and recycling such kind of wastes with economical and environmentally friendly techniques is crucial to the sustainable rare-earth ***,the current multistage wet process recycling technique for the sludge wastes involves high fabrication cost,excessive energy consumption,and heavy environmental ***,short-process recycling techniques for Nd-Fe-B sintered magnet wastes have drawn increasing attention in the past *** this paper,we review recent efforts into short-process recycling Nd-Fe-B sintered magnet sludge wastes with emphasis on in-situ recycling techniques.

关键词： Nd-Fe-B sintered Magnet sludge wastes Rare earths Short-process recycling In-situ recycling

Reaction-tunable diffusion bonding to multilayered Cu mesh/ZK61 Mg foil composites with thermal conductivity and lightweight synergy

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Journal of Materials Science & Technology 2023年第8期139卷 10-22页

作者： Fanjin Yao Guoqiang You Sheng Zeng Dashi Lu yue ming College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China The State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology at ShenzhenShenzhen 518055China

The thermal properties of Mg alloys require further optimization to encounter the increasingly severe heat dissipation demands of high-power densities and highly integrated electronic *** this study,a novel strategy of reaction-tunable diffusion bonding(RDB)was applied to manipulate the inter-facial reaction in the multilayered Cu mesh/ZK61 Mg foil *** displacement of the punch was utilized to quantify the degree of reactive diffusion with adjustable,visible,and high *** inter-face was artificially manipulated to produce the fluid Mg-Zn eutectic liquid phase filling the interfacial gap at high temperature for a short time,followed by diffusion bonding at low *** thermal conductivity of the composites first increased and then decreased,which was synthetically affected by the amelioration of metallurgical bonding and the moderately reactive consumption of *** reinforcement Cu was converted from the Hasselman-Johnson model to the Rayleigh model,reflecting the optimization of the interfacial bonding *** composites with thermal conductivity and lightweight synergy were fabricated ***,RDB is a progressive technique,shedding lights on the innovative lightweight metal matrix composites with high thermal conductivities relevant to the 5G communications and new energy vehicle industries.

关键词： Metal-matrix composites(MMCs) Thermal properties Microstructures Reaction-tunable diffusion bonding

Study on magnetization reversal behavior for annealed Nd2Fe14B/α-Fe nancomposite alloys

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Journal of Rare Earths 2013年第8期31卷 759-764页

作者： ZHANG Pengyue PAN Minxiang GE Hongliang yue ming LIU Weiqiang College of Materials Science & Engineering China Jiliang University Hangzhou 310018 China College of Materials Science & Engineering Beijing University of Technology Beijing 100124 China

Effect of thermal annealing on the magnetization reversal behavior of α-Fe/Nd2Fe14B alloys was investigated. A drastic in- crease of the remanence Mr from 0.67 up to 0.87 T and remanence ratio Mr/Ms from 0.66 up to 0.76, respectively, was observed in the α-Fe/NdEFel413 alloys annealed at 610 ℃ as compared with the as-quenched sample. Whereas the further annealing at 680 ℃ resulted in a strong increase of the corecivity Hc as high as 491 kA/m but a slight decrease in Mr. The analysis result of the magnetization re- versal behavior showed that the maximum value of the integrated recoil loop area about 1.58 kJ/m3 was obtained in the α-Fe/Nd2Fe14B alloys at the annealing temperature of 610℃, significantly lower than other annealed samples. This indicated a sig- nificant advantage for the application of this material as permanent magnets in electrical machines and generators due to a low energy loss.

关键词： nanocomposite magnetization reversal behavior recoil loop rare earths

Adaptive security control of time-varying constraints nonlinear cyber-physical systems with false data injection attacks

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Journal of Control and Decision 2024年第1期11卷 50-59页

作者： yue-ming Wang Yuan-Xin Li Department of Science Liaoning University of TechnologyJinzhouPeople’s Republic of China

In this article,an adaptive security control scheme is presented for cyber-physical systems(CPSs)suffering from false data injection(FDI)attacks and time-varying state ***,an adaptive bound estimation mechanism is introduced in the backstepping control design to mitigate the effect of FDI ***,to solve the unknown sign time-varying statefeedback gains aroused by the FDI attacks,a type of Nussbaum function is employed in the adaptive security ***,by constructing a barrier Lyapunov function,it can be ensured that all signals of controlled system are bounded and the time-varying state constraints are not ***,the provided simulation examples demonstrate the effectiveness of the proposed controller.

关键词： Neural networks backstepping technology false data injection(FDI)attacks nonlinear cyber-physical systems controls