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Joint Model of Wind Speed and Corresponding Direction Based on Wind Rose for Wind Energy Exploitation

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Journal of Ocean University of China 2022年第4期21卷 876-892页

作者： YANG Zihao LIN Yifan dong sheng College of Engineering Ocean University of ChinaQingdao 266100China Huadian Heavy Industries Co. Ltd.Beijing 100070China

As a common and extensive datum to analyze wind,wind rose is one of the most important components of the meteorological *** this study,a model is proposed to establish the joint probability distribution of wind speed and direction using grouped data of wind *** the basis of the model,an algorithm is presented to generate pseudorandom numbers of wind speed and paired direction ***,the proposed model and algorithm are applied to two weather stations located in the Liaodong *** the models built for the two cases,a novel graph representing the continuous joint probability distribution of wind speed and direction is plotted,showing a strong correlation to the corresponding wind ***,the joint probability distributions are utilized to evaluate wind energy potential *** cooperation with Monte Carlo simulation,the model can approximately predict annual directional extreme wind speed under different return periods under the condition that the wind rose can represent the meteorological characters of the wind field *** model is beneficial to design and install wind turbines.

关键词： angular-linear distribution wind speed wind direction wind rose wind energy Monte Carlo simulation

Transformers in computational visual media:A survey

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Computational Visual Media 2022年第1期8卷 33-62页

作者： Yifan Xu Huapeng Wei Minxuan Lin Yingying Deng Kekai sheng Mengdan Zhang Fan tang Weiming dong Feiyue Huang Changsheng Xu NLPR Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100040China School of Artificial Intelligence Jilin UniversityChangchun 130012China Youtu Lab Tencent Inc.Shanghai 200233China CASIA-LLVISION Joint Lab Beijing 100190China

Transformers,the dominant architecture for natural language processing,have also recently attracted much attention from computational visual media researchers due to their capacity for long-range representation and high *** are sequence-to-sequence models,which use a selfattention mechanism rather than the RNN sequential ***,such models can be trained in parallel and can represent global *** study comprehensively surveys recent visual transformer *** categorize them according to task scenario:backbone design,high-level vision,low-level vision and generation,and multimodal *** key ideas are also *** from previous surveys,we mainly focus on visual transformer methods in low-level vision and *** latest works on backbone design are also reviewed in *** ease of understanding,we precisely describe the main contributions of the latest works in the form of *** well as giving quantitative comparisons,we also present image results for low-level vision and generation *** costs and source code links for various important works are also given in this survey to assist further development.

关键词： visual transformer computational visual media(CVM) high-level vision low-level vision image generation multi-modal learning

Intensity Estimation of Extreme Meteorological and Hydrological Factors Induced by Tropical Cyclones Affecting Hong Kong

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Journal of Ocean University of China 2023年第2期22卷 313-323页

作者： TAO Shanshan HUA Yunfei dong sheng College of Engineering Ocean University of ChinaQingdao 266100China

Hong Kong is often affected by tropical *** Hong Kong observatory issues warning signals based on the impact of tropical cyclones on the *** joint frequency analysis of tropical cyclones in Hong Kong can provide a scientific basis for disaster reduction and prevention and post-disaster reconstruction of tropical ***,the maximum hourly mean wind speed(W),warning signal duration(D),maximum sea level(L),and total rainfall(R)of each tropical cyclone that affected Hong Kong from 1985 to 2019 are selected and fitted using the Gumbel,Weibull,Pearson type 3,and lognormal ***,bivariate copula functions,such as the Clayton,Frank,Gumbel-Hougaard,and Gaussian copulas,are applied to construct the joint probability models of W,D,L,and R,*** joint return periods of W and D and those of L and R are defined as the meteorological and hydrological intensities of tropical cyclones,*** results show that the joint return periods are good indicators of the comprehensive effect of the meteorological and hydrological intensities of tropical *** necessary correlation between meteorological and hydrological intensities of tropical cyclones *** meteorological and hydrological intensities of tropical cyclones show an upward trend in recent years.

关键词： tropical cyclone warning signal meteorological intensity hydrological intensity copula

Intensity of Level Ice Simulated with the CICE Model for Oil-Gas Exploitation in the Southern Kara Sea, Arctic

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Journal of Ocean University of China 2022年第5期21卷 1099-1108页

作者： DUAN Chenglin WANG Zhifeng dong sheng College of Engineering Ocean University of ChinaQingdao 266100China

Sea ice is the predominant natural threat to marine structures and oil-gas exploitation in the ***,for ice-resistant structural design,long-term successive level ice thickness measurements are still *** fill this gap in the southern Kara Sea,the Los Alamos Sea Ice Model(CICE)is applied to achieve better simulation at the local and regional *** on the validation against ice thickness observations in March and April in 1980-1986,the statistical root-mean-square error is determined to be less than 0.2 ***,based on the hindcast data,the spatiotemporal distributions of level ice thickness are analyzed annually,seasonally,and monthly,with thicker level ice of 1.2-1.5 m in spring and large ice-free zones in September and *** floating platforms,a novel ice grade criterion with five classifications,namely,excellent,good,moderate,severe,and catastrophic,is *** first two grades are most suitable for offshore activities,particularly from August to October,and the moderate grade is acceptable if with ice-resistant ***,hostile ice conditions are discussed in terms of the generalized extreme value *** statistics reveal that at a return period of 100 yr,extreme level ice is primarily between 0.6 m and 1.0 m in *** present investigation could be a useful reference for a feasibility study of the potential risk analysis and ice-resistant operation of oil-gas exploitation in the Arctic.

关键词： level ice CICE spatiotemporal distribution return period ice-resistant floating platform southern Kara Sea

Feature extraction for latent fault detection and failure modes classification of board-level package under vibration loadings.

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Science China(Technological Sciences) 2015年第11期58卷 1905-1914页

作者： tang Wei JING Bo HUANG YiFeng sheng ZengJin Aeronautics and Astronautics Engineering College Air Force Engineering University

A feature extraction for latent fault detection and failure modes classification method of board-level package subjected to vibration loadings is presented for prognostics and health management(PHM) of electronics using adaptive spectrum kurtosis and kernel probability distance clustering. First, strain response data of electronic components is filtered by empirical mode decomposition(EMD) method based on maximum spectrum kurtosis(SK), and fault symptom vector is developed by computing and reconstructing the envelope spectrum. Second, nonlinear fault symptom data is mapped and clustered in sparse Hilbert space using Gaussian radial basis kernel probabilistic distance clustering method. Finally, the current state of board level package is estimated by computing the membership probability of its envelope spectrum. The experimental results demonstrated that the method can detect and classify the latent failure mode of board level package effectively before it happened.

关键词： board-level package vibration loading spectrum kurtosis kernel probabilistic distance clustering

Multiphase flow model developed for simulating gas hydrate transport in horizontal pipe

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Applied Mathematics and Mechanics(English Edition) 2016年第9期37卷 1193-1202页

作者： Shuai tang Caixi LIU Yuhong dong Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University

The hydrate formation or dissociation in deep subsea flow lines is a challenging problem in oil and gas transport systems. The study of multiphase flows is complex while necessary due to the phase changes （i.e., liquid, solid, and gas） that occur with increasing the temperature and decreasing the pressure. A one-dimensional multiphase flow model coupled with a transient hydrate kinetic model is developed to study the characteristics of the multiphase flows for the hydrates formed by the phase changes in the pipes. The multiphase flow model is derived from a multi-fluid model, while has been widely used in modelling multiphase flows. The heat convection between the fluid and the ambient through the pipe wall is considered in the energy balance equation. The developed multiphase flow model is used to simulate the procedure of the hydrate transport. The results show that the formation of the hydrates can cause hold-up oscillations of water and gas.

关键词： multiphase flow hydrate slug flow phase change

Functional Amphiphilic Poly(2-oxazoline)Block Copolymers as Drug Carriers:the Relationship between Structure and Drug Loading Capacity

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Chinese Journal of Polymer Science 2021年第7期39卷 865-873页

作者： Si dong sheng Ma Zhi-Lin Liu Li-Li Ma Yu Zhang Zhao-Hui tang Ming-Xiao Deng Wan-Tong Song College of Chemistry Northeast Normal UniversityChangchun 130024China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Poly(2-oxazoline)(POx)is a kind of polymeric amides that can be viewed as conformational isomers of polypeptides with excellent cyto-and hemo-compatibility,and is promising to be used as drug ***,the drug loading capacity(DLC)of POx for many drugs is still low except several hydrophobic ones including paclitaxel(PTX).Herein,we prepared a series of amphiphilic POx block copolymers with various functional groups,and investigated the relationship between functional structures and the *** POxs with benzyl,carboxyl,and amino groups in the side-chain were synthesized based on a poly(2-methyl-2-oxazoline)-block-poly(2-buty1-2-oxazoline-co-2-buteny1-2-oxazoline)(PMeOx-P(nBuOx-co-ButenOx),PMBEOx)precursor,followed by click reaction between vinyl and the 2-phenylethanethiol,thioglycolic acid and *** thin-film hydration method,eight commonly used drugs with various characteristics were encapsulated within these functional POx *** found that amine-containing drugs were more easily encapsulated by POx with carboxyl groups,while amine functionalities in POx enhanced the loading capacity of drugs with carboxyl *** addition,n-n interactions resulted in enhanced DLC of most drugs,except several hydrophobic drugs with aromatic to total carbon ratios less than *** general,we could successfully encapsulate all the selected drugs with a DLC%over 10%using properly selected functional *** above results confirm that the DLC of polymeric carriers can be adjusted by modifying the functional groups,and the prepared series of functional POxs provide an option for various drug loadings.

关键词： Poly(2-oxaozoline) Polymeric micelles Drug loading π-πInteraction Electrostatic interaction

Energy Scattering of a Generalized Davey–Stewartson System in Three Dimension

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Acta Mathematica Sinica,English Series 2017年第9期33卷 1206-1224页

作者： Jing LU Xing dong tang School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China Institute of Applied Physics and Computational Mathematics Beijing 100088P.R.China

In this paper, we study the global scattering result of the solution for the generalized Davey-Stewartson system The main difficulties are the failure of the interaction Morawetz estimate and the asymmetrical structure of nonlinearity （in particular, the nonlinearity is non-local）. To compensate, we utilize the strategy derived from concentration-compactness idea, which was first introduced by Kenig and Merle .

关键词： Davey-Stewartson system scatter global well-posedness

An Improved Time Domain Approach for Analysis of Floating Bridges Based on Dynamic Finite Element Method and State-Space Model

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China Ocean Engineering 2022年第5期36卷 682-696页

作者： XIANG sheng CHENG Bin ZHANG Feng-yu tang Miao State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure Shanghai Jiao Tong UniversityShanghai 200240China Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Civil Engineering Fuzhou UniversityFuzhou 350108China

The floating bridge bears the dead weight and live load with buoyancy,and has wide application prospect in deep-water transportation *** structural analysis of floating bridge is challenging due to the complicated fluid-solid coupling effects of wind and *** this research,a novel time domain approach combining dynamic finite element method and state-space model(SSM)is established for the refined analysis of floating *** dynamic coupled effects induced by wave excitation load,radiation load and buffeting load are carefully ***-precision fitted SSMs for pontoons are established to enhance the calculation efficiency of hydrodynamic radiation forces in time *** dispersion relation is also introduced in the analysis model to appropriately consider the phase differences of wave loads on *** proposed approach is then employed to simulate the dynamic responses of a scaled floating bridge model which has been tested under real wind and wave loads in *** numerical results are found to agree well with the test data regarding the structural responses of floating bridge under the considered environmental *** proposed time domain approach is considered to be accurate and effective in simulating the structural behaviors of floating bridge under typical environmental conditions.

关键词： floating bridge time domain analysis dynamic analysis state-space model environmental load