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Determination of the geographical origin of Chinese teas based on stable carbon and nitrogen isotope ratios

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第10期13卷 824-830页

作者： long ZHANG Jia-rong PAN cheng ZHU College of life Sciences Zhejiang UniversityHangzhou 310058China College of life Sciences China Jiliang UniversityHangzhou 310018China

The objective of this study was to investigate the geographical origin of Chinese teas using carbon and nitrogen stable isotope ratio *** results showed that inter-provincial dispersion of teas in Guangdong(GD),Guangxi(GX),Hainan(HA),Fujian(FJ),Shandong(SD),Sichuan(SC),Chongqing(CQ),and Henan(HN) provinces was high,while in Zhejiang(ZJ),Hubei(HB),Yunnan(YN),and Anhui(AH) provinces,it was *** samples from GD,GX,HA,and FJ provinces were clustered in one group and separated from those from AH and HB ***,carbon and nitrogen stable isotope ratio technology could discriminate teas from among some provinces of China,but not from among *** separation might be obtained with a combination of isotopic ratios and other indexes,such as elemental data and organic components.

关键词： Geographical origin Stable carbon isotope ratios Stable nitrogen isotope ratios Tea

Formation Control for Water-Jet USV Based on Bio-Inspired Method

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China Ocean Engineering 2018年第1期32卷 117-122页

作者： FU Ming-yu WANG Duan-song WANG cheng-long College of Automation Harbin Engineering University

The formation control problem for underactuated unmanned surface vehicles(USVs) is addressed by a distributed strategy based on virtual leader strategy. The control system takes account of disturbance induced by external environment. With the coordinate transformation, the advantage of the proposed scheme is that the control point can be any point of the ship instead of the center of gravity. By introducing bio-inspired model, the formation control problem is addressed with backstepping method. This avoids complicated computation, simplifies the control law,and smoothes the input signals. The system uniform ultimate boundness is proven by lyapunov stability theory with Young inequality. Simulation results are presented to verify the effectiveness and robust of the proposed controller.

关键词： water-jet USV bio-inspired model backstepping formation control

Micromechanical Behavior and Failure Mechanism of F / B Multi-phase High Performance Steel

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Journal of Iron and Steel Research International 2016年第5期23卷 489-494页

作者： Cun-jiang TANG Shi-long lIU cheng-jia SHANG School of Materials Science and Engineering University of Science and Technology Beijing

The deformation and micro-voids formation mechanisms in ferrite / bainite（ F / B） multi-phase steel with the volume fraction of bainite less than 50% were studied by numerical simulation and experimental observation. The results show that the micro-strain concentrates at the soft / hard phase（ F / B） interface in the multi-phase steel,which should be correlated with the mechanism of incoordinate deformation. During the necking of the steel,the micro-voids initially form around the F / B interface,which also form in ferrite and bainite with the severe strain. The micro-voids in bainite are more dense and finer than those in ferrite. The failure mechanism of bainite is the coalescence of micro-voids,and the failure mechanism of ferrite is the growth and tearing of micro-voids. Due to the different failure mechanisms of ferrite and bainite,a suitable part of soft phase would be beneficial to the capability of anti-failure of F / B multi-phase steel during the ductile fracture.

关键词： ferrite / bainite multi-phase steel numerical simulation ferrite / bainite interface micro-strain micro-void failure mechanism soft phase

A Robust Indoor localization Algorithm Based on Polynomial Fitting and Gaussian Mixed Model

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China Communications 2023年第2期20卷 179-197页

作者： long cheng Peng Zhao Dacheng Wei Yan Wang Department of Computer and Communication Engineering Northeastern UniversityQinhuangdao 066004China

Wireless sensor network(WSN)positioning has a good effect on indoor positioning,so it has received extensive attention in the field of ***-line-of sight(NlOS)is a primary challenge in indoor complex *** this paper,a robust localization algorithm based on Gaussian mixture model and fitting polynomial is proposed to solve the problem of NlOS ***,fitting polynomials are used to predict the measured *** residuals of predicted and measured values are clustered by Gaussian mixture model(GMM).The lOS probability and NlOS probability are calculated according to the clustering *** measured values are filtered by Kalman filter(KF),variable parameter unscented Kalman filter(VPUKF)and variable parameter particle filter(VPPF)in *** distance value processed by KF and VPUKF and the distance value processed by KF,VPUKF and VPPF are combined according to ***,the maximum likelihood method is used to calculate the position coordinate *** simulation comparison,the proposed algorithm has better positioning accuracy than several comparison algorithms in this *** it shows strong robustness in strong NlOS environment.

关键词： wireless sensor network indoor localization NlOS environment gaussian mixture model(GMM) fitting polynomial

Stability,electronic structure,and optical properties of lead-free perovskite monolayer Cs3B2X9(B=Sb,Bi;X=Cl,Br,I)and bilayer vertical heterostructure Cs_(3)B_(2)X_(9)/Cs3B’2X9(B,B’=Sb,Bi;X=Cl,Br,I)

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Chinese Physics B 2022年第2期31卷 538-546页

作者： Yaowen long Hong Zhang Xinlu cheng College of Physics Sichuan UniversityChengdu 610065China Key laboratory of High Energy Density Physics and Technology(Ministry of Education) Sichuan UniversityChengdu 610065China Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China

The lead-free perovskites Cs_(3)B_(2)X_(9)(B=Sb,Bi;X=Cl,Br,I)as the popular photoelectric materials have excellent optical properties with lower *** this study,we systematically investigate the stable monolayer Cs_(3)B_(2)X_(9)and bilayer vertical heterostructure Cs_(3)B_(2)X_(9)/Cs3B02X9(B,B0=Sb,Bi;X=Cl,Br,I)via first-principles *** exploring the electrical structures and band edge positions,we find the band gap reduction and the band type transition in the heterostructure Cs_(3)B_(2)X_(9)/Cs3B02X9 due to the charge transfer between ***,the results of optical properties reveal light absorption from the visible light to UV region,especially monolayer Cs3Sb2I9 and heterostructure Cs3Sb2I9/Cs3Bi2I9,which have absorption peaks in the visible light region,leading to the possibility of photocatalytic water *** results provide insights for more two-dimensional semiconductors applied in the optoelectronic and photocatalytic fields.

关键词： first principles simulations lead-free perovskite monolayer Cs_(3)B_(2)X_(9) vertical heterostructure Cs_(3)B_(2)X_(9)/Cs_(3)B’_(2)X_(9) photoelectric materials

linguistic landscape and its impacts on place-making in mountain destination:A case of Mogan Mountain Town of Huzhou City,China

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Journal of Mountain Science 2024年第5期21卷 1613-1629页

作者： lI Chenyan lU Song long cheng ZHU Jiaheng School of Tourism Shanghai Normal UniversityShanghai 200034China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200034China

The place and placeness are believed to be a crucial perspective for comprehending the transformative dynamics of tourist destinations in the context of globalization and the rapid development of the tourism *** the material carrier of language,linguistic landscape is an intermediary for people to endow emotions and personalities into the place,becoming an effective path for exploring the place-making in a certain *** Mountain is a famous national tourist resort,which is located in Mogan Mountain Town,Deqing County,Huzhou City,*** is a good case area for studying the relationship between linguistic landscape and placemaking in tourist *** are two theories that form the theoretical foundation of the study,namely the place and the ***,the results showed the overall style of the linguistic *** labelling(52.7%),official signs(55.3%),and standardized Chinese characters predominantly shaped the linguistic landscape,with English and other languages being ***,from the perspective of three dimensions of the geosemiotics framework,such as inscription,language preference,and placement position,we conduct a comprehensive semiotic analysis of the linguistic landscape,which encompasses diverse facets such as fonts,materials,shifts in state,text vectors,and symmetrical ***,we explore the influence of linguistic landscapes on the place-making of Mogan Mountain through the dimensions of location,locale,and sense of *** information on linguistic landscapes indicates the geographical *** linguistic landscapes play an important role in constructing the language order,nostalgic atmosphere,exotic atmosphere,and elegant and tasteful lifestyle of the public space in Mogan *** of linguistic landscapes,including tourists and residents,generate and identify with the unique sense of place in Mogan *** linguistic landscapes construct the destinati

关键词： linguistic landscape Place-making Tourist destination Geosemiotics Place theory Place branding Mogan Mountain Town China

A short review on recent progress of Bi/semiconductor photocatalysts:The role of Bi metal

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Chinese Chemical letters 2020年第10期31卷 2583-2590页

作者： Qian Chen Xuanrui cheng Huimin long Yongfang Rao Department of Environmental Science and Engineering Xi'an Jiaotong UniversityXi'an 710049China

Bi/semiconductor photocatalysts have extensively been applied in the production of hydrogen,CO_(2) reduction and environmental remediation in recent *** short review summarizes the role of Bi metal as a plasma photocatalyst and *** a cocatalyst,Bi metal can be electron/hole trappers,charge transfer mediators,or oxygen vacancy *** addition,the preparation methods of the Bi/semiconductor photocatalysts are also *** and future research directions related to Bi/semiconductor photocatalysts are discussed and summarized,including the use of advanced characterization techniques to refine the reaction mechanism,the difficulties of preparing Bi single atom catalyst,and the improvement of the reduction ability of Bi-based *** review helps understand the reaction mechanisms of the composite photocatalytic systems containing Bi metal and proposes new perspectives for designing the photocatalysts which can control air pollution via a reductive process.

关键词： Bi metal Plasma photocatalyst Cocatalyst Electron/hole trappers Charge transfer medium

Numerical analysis of coupled sloshing and motion of a cylindrical FPSO in regular waves

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Journal of Hydrodynamics 2024年第3期36卷 457-465页

作者： Wei-wen Zhao Xiao-long Yang De-cheng Wan Computational Marine Hydrodynamics lab(CMHl) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Offshore Oil Engineering Co.ltd. Tianjin300461China

In this paper,the coupled sloshing and motion characteristics of a cylindrical floating production storage offloading(CFPSO)are numerically investigated by means of computational fluid dynamics(CFD)*** simulations are performed using an in-house CFD solver naoe-FOAM-SJTU which is developed based on *** active wave generating-absorbing boundary condition(GABC)is utilized for wave generation and *** stabilized k-omega SST turbulence model are used to avoid excessive eddy viscosity near the free *** with and without partially filled liquid tanks in regular waves with different wave periods are simulated and vertical planar motions such as surge,heave and pitch response amplitude operators(RAOs)are *** due to liquid sloshing and wave loads are extracted and *** free surface motions inside liquid tanks in one wave period presented to explain the motion characteristics.

关键词： Coupled analysis liquid sloshing wave motion cylindrical floating production storage offloading(CFPSO)

A methodological framework of landslide quantitative risk assessment in areas with incomplete historical landslide information

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Journal of Mountain Science 2023年第9期20卷 2665-2679页

作者： lI Xia cheng Jiu-long YU De-Hao College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China Research Institute of Engineering Design Beijing 100083China

landslide risk assessment(lRA)is of great significance to hazard prevention and ***,the historical landslide information is incomplete in most areas,which makes the landslide quantitative risk assessment(lQRA)extremely *** research proposed a set of frameworks for lQRA,so as to achieve lQRA in areas with incomplete historical landslide ***,we constructed the convolutional neural network(CNN)model suitable for landslide susceptibility assessment(lSA)by studying the structure and hyperparameters optimization of ***,we proposed a method to calculate the temporal probability by using the Poisson model based on the time range of historical landslides occurrence,and then conducted landslide hazard assessment(lHA).Then,we established a mathematical model for landslide intensity of shallow landslide based on landslide area and slope,aiming at solving the problem that it is difficult to calculate landslide intensity due to the lack of landslide volume and *** on the landslide intensity and the hazard-resistant capacity of the element at risk,we assessed the landslide ***,population risk map and economic risk map are obtained based on the landslide hazard,vulnerability,and estimated value of the elements at *** proposed lQRA framework was applied to Tumen City,China for testing and field *** the results,the CNN model built can help improve the accuracy of *** proposed temporal probability calculation method is conducive to the completion of lHA in areas with incomplete historical landslide *** established landslide intensity mathematical model has certain *** the landslide risk map is obtained through appropriate simplification and substitution estimation,its final value cannot be used as an accurate prediction of future losses,but it can be used as a reference for the extent of potential losses,so as to determine the areas where hazard prevention and

关键词： landslide Quantitative risk assessment Convolutional neural network Hazard assessment Vulnerability