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A New Noninvasive Dual Pulse Wave Doppler Method for Measuring Local Pulse Wave Velocity:In Vitro and In Vivo Studies

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A New Noninvasive Dual Pulse Wave Doppler Method for Measuri...

Experimental and Computational Investigations on Severe Slugging in A Catenary Riser

中华医学会第十三次全国超声医学学术会议

作者： Zhen Wang Tie-sheng Cao Li-jun Yuan yun-you duan Yong Yang Yuan-ling Liu Chang-yang Xing Department of Ultrasound Diagnostics Tangdu Hospitalthe Fourth Military Medical University

Objectives This study aimed to investigate and evaluate the validity and reproducibility of our new noninvasive dual pulse wave Doppler(DPWD) method for measuring the local arterial pulse wave velocity(PWV), which has been of increasing importance with useful diagnostic informationof biomechanical properties for local artery wall,through in vitro and in vivo ***,among the current noninvasive methods,none could

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China Ocean Engineering 2017年第6期31卷 653-664页

作者： duan Jin-long CHEN Ke you yun-xiang GAO Song Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China Marine Design & Research Institute of China Shanghai 200240 China

Severe slugging can occur in a pipeline-riser system at relatively low liquid and gas flow rates during gas-oil transportation, possibly causing unexpected damage to the production facilities. Experiments with air and water are conducted in a horizontal and downward inclined pipeline followed by a catenary riser in order to investigate the mechanism and characteristics of severe slugging. A theoretical model is introduced to compare with the experiments. The results show that the formation mechanism of severe slugging in a catenary riser is different from that in a vertical riser due to the riser geometry and five flow patterns are obtained and analyzed. A gas-liquid mixture slug stage is observed at the beginning of one cycle of severe slugging, which is seldom noticed in previous studies. Based on both experiments and computations, the time period and variation of pressure amplitude of severe slugging are found closely related to the superficial gas velocity, implying that the gas velocity significantly influences the flow patterns in our experiments. Moreover, good agreements between the experimental data and the numerical results are shown in the stability curve and flow regime map, which can be a possible reference for design in an offshore oil-production system.

关键词： severe slugging flow patterns pipeline-catenary-riser system superficial gas and liquid velocities theoretical model

Modelling of the Vortex-Induced Motion of A Single-Column Platform with Non-Linear Mooring Stiffness Using the Coupled Wake Oscillators

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China Ocean Engineering 2019年第4期33卷 459-467页

作者： HU Xiao-feng ZHANG Xin-shu you yun-xiang duan Jin-long State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration (CISSE) School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

A phenomenological model for predicting the vortex-induced motion (VIM) of a single-column platform with non- linear stiffness has been proposed. The VIM model is based on the couple of the Duffing-van der Pol oscillators and the motion equations with non-linear terms. The model with liner stiffness is presented for comparison and their results are compared with the experiments in order to calibrate the model. The computed results show that the predicted VIM amplitudes and periods of oscillation are in qualitative agreements with the experimental data. Compared with the results with linear stiffness, it is found that the application of non-linear stiffness causes the significant reductions in the in-line and transverse motion amplitudes. Under the non-linear stiffness constraint, the lock-in behavior is still identified at 8

关键词： vortex-induced motion single-column platform wake oscillators non-linear stiffness

Force Feedback Coupling with Dynamics for Physical Simulation of Product Assembly and Operation Performance

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Chinese Journal of Mechanical Engineering 2015年第1期28卷 164-172页

作者： LIU Zhenyu TAN Jianrong duan Guifang FU yun State Key Laboratory of CAD&CG Zhejiang University

Most existing force feedback methods are still difficult to meet the requirements of real-time force calculation in virtual assembly and operation with complex objects. In addition, there is often an assumption that the controlled objects are completely flee and the target object is only completely fixed or flee, thus, the dynamics of the kinematic chain where the controlled objects are located are neglected during the physical simulation of the product manipulation with force feedback interaction. This paper proposes a physical simulation method of product assembly and operation manipulation based on statistically learned contact force prediction model and the coupling of force feedback and dynamics. In the proposed method, based on hidden Markov model （HMM） and local weighting learning （LWL）, contact force prediction model is constructed, which can estimate the contact force in real time during interaction. Based on computational load balance model, the computing resources are dynamically assigned and the dynamics integral step is optimized. In addition, smoothing process is performed to the force feedback on the synchronization points. Consequently, we can solve the coupling and synchronization problems of high-frequency feedback force servo. low-frequency dynamics solver servo and scene rendering servo, and realize highly stable and accurate force feedback in the physical simulation of product assembly and operation manipulation. This research proposes a physical simulation method of product assembly and operation manipulation.

关键词： contact force prediction force feedback multi-rate coupling physical simulation of manipulation virtual assembly

马铃薯转录因子StFBH3对非生物逆境胁迫的响应分析

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作物学报 2025年第1期51卷 247-259页

作者：宋倩娜宋慧洋李京昊段永红梅超冯瑞云山西农业大学农学院山西太谷030801 山西省农业科学院作物科学研究所山西太原030031

bHLH (basic helix-loop-helix)作为植物界第二大类转录因子,在植物应对环境胁迫响应中起着重要的调控作用。探究马铃薯(Solanum tuberosum L.) bHLH家族基因功能将为马铃薯改良和育种提供一定的理论依据。本研究克隆了马铃薯StFBH3基因... 详细信息

bHLH (basic helix-loop-helix)作为植物界第二大类转录因子,在植物应对环境胁迫响应中起着重要的调控作用。探究马铃薯(Solanum tuberosum L.) bHLH家族基因功能将为马铃薯改良和育种提供一定的理论依据。本研究克隆了马铃薯StFBH3基因(Gene ID:102582309),利用qPCR技术分析了不同逆境胁迫下StFBH3基因表达模式,结果表明, StFBH3基因在马铃薯根和叶中的表达量较高,且该基因的表达受渗透、高盐和脱落酸(abscisic acid, ABA)诱导;以过表达StFBH3基因的马铃薯试管苗为材料,在分别含有不同浓度甘露醇(mannitol)、NaCl和ABA的MS培养基中,过表达StFBH3马铃薯株系的叶绿素含量显著高于野生型,根长显著长于野生型。在干旱和高盐处理下,土壤栽培的过表达马铃薯株系较野生型表现较强的耐受性,叶片相对含水量、叶绿素含量和过氧化物歧化酶(SOD)活性显著高于野生型。qPCR分析发现,干旱和盐胁迫处理下相关基因(KAT1)的表达量在过表达马铃薯株系中较野生型显著降低。以上结果表明, StFBH3基因可能在马铃薯对渗透、干旱和高盐等胁迫响应中起正向调控作用。本研究也为StFBH3基因在马铃薯中的生物学功能深入理解提供一定的参考依据。

关键词：马铃薯 StFBH3 转录因子逆境胁迫

Dramatic impact of metric choice on biogeographical regionalization

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Plant Diversity 2020年第2期42卷 67-73页

作者： Jian-Fei Ye yun Liu Zhi-duan Chen State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China Beijing Botanical Garden.Institute of Botany Chinese Academy of SciencesBeijing W0093China

For a quantitative biogeographical regionalization,the choice of an appropriate dissimilarity index to measure pairwise distances is *** different metrics have been used,but there is no specific study to test the impact of metric choice on biogeographical *** herein applied a hierarchical cluster analysis on the mean nearest taxon distance(MNTD)and the phylogenetic turnover component of the SФrensen dissimilarity index(pβsim)pairwise distances to generate two schemes of phylogenetic regio nalization of the Chinese flora,and then evaluated the effect of metric *** regionalization based on MNTD was influenced by richness differences,but regionalization based on pβsim can clearly reflect the evolutionary history of the Chinese *** provided a brief description of the five regions identified by pβsim,and the regionalization can help develop strategies to effectively conserve the taxa and floristic regions with different origins and evolutionary histories.

关键词： Angiosperms Chinese flora Dissimilarity index Distance metrics Spatial turnover

Impact of Media Information on Social Response in Disasters:A Case Study of the Freezing‑Rain and Snowstorm Disasters in Southern China in 2008

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International Journal of Disaster Risk Science 2024年第1期15卷 73-87页

作者： Jia He Wenjing duan Yuxuan Zhou yun Su College of Geographic Science and Tourism Xinjiang Normal UniversityUrumqi 830054China Xinjiang Laboratory of Lake Environment and Resources in Arid Zone Urumqi 830054China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China

Disaster information content is an objective mapping of disaster situations,social response,and public *** response to emergency is an important mechanism for implementing and guaranteeing emergency management of major natural hazard-related *** how disaster information content affects social response to emergencies is helpful for managing risk communication and efficient disaster *** on the 2008 freezing-rain and snowstorm disasters in southern China,this study used Python to extract 7,857 case-related media reports and applied natural language processing for text *** used three typical cases to identify and analyze disaster media report content and the relationship between these reports and the social response to the *** categories of disaster response-such as prewarning and forecasting,announcements by the authorities,and social mobilization-appeared in the disaster information in the media,along with disaster impact information,that is,real-time disaster *** response information and an appropriate amount of disaster impact information played important roles in prewarning,disaster relief,public opinion guidance,and social stability maintenance and can serve important functions in communicating with all stakeholders of emergency management,assisting or influencing emergency departments or individuals in decision making,and eliminating "information islands." Empathy caused the general public to become "disaster responders" through receiving *** and an excess of negative information may have a perverse amplification effect on public opinion and increase the unpredictability of the disaster situation and the risk of social crisis.

关键词： Emergency management Freezing-rain and snowstorm disasters Media reports on disasters Social response to emergencies China

Versatile Inorganic Oligomer-based Photochromic Spiropyrane Gels

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Chinese Journal of Structural Chemistry 2022年第5期41卷 37-47页

作者： Jiajia Song Wei duan yun Chen Xiangyang Liu State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China College of Ocean and Earth Sciences College of MaterialsCollege of Physical Science and TechnologyState Key Laboratory of Marine Environmental Science(MEL)Research Institute for Biomimetics and Soft MatterXiamen UniversityXiamen 361005China Department of Physics National University of Singapore2 Science Drive 3Singapore 117542Singapore

Here we report an example of a general strategy for the immobilization of various different photochromic spiropyran molecules on eco-friendly cheap *** spiropyrans are encapsulated in calcium salt oligomers-based gels by centrifugation,forming an inorganic oligomer-based gelatinous photoswitchable hybrid ***^(2+)is also used to regulate the optical properties of spiropyrans through *** oligomer-based gel can not only provide the space required for photoisomerization,but also reduce the interference of the surrounding environment on the photochromic ***,a practical paper-based and colloidal flexible substrate platform is constructed for the removal and naked-eye detection of liquid and gaseous hydrazine at room temperature based on the reactivity of the formyl group on spiro-pyrans loaded in Ca3(PO4)2 *** general strategy can be used for other inorganic oligomer-based molecular switches and sensing systems.

关键词： inorganic oligomer photochromic gels naked-eye detection of hydrazine

Agricultural information dissemination using ICTs:A review and analysis of information dissemination models in China

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Information Processing in Agriculture 2016年第1期3卷 17-29页

作者： yun Zhang Lei Wang Yanqing duan Foreign Economic Cooperation Centre Ministry of AgricultureBeijingChina Business and Information Systems Research Centre University of BedfordshireLutonUK

Over the last three decades,China’s agriculture sector has been transformed from the traditional to modern practice through the effective deployment of Information and Communication Technologies(ICTs).Information processing and dissemination have played a critical role in this transformation *** studies in relation to agriculture information services have been conducted in China,but few of them have attempted to provide a comprehensive review and analysis of different information dissemination models and their *** paper aims to review and identify the ICT based information dissemination models in China and to share the knowledge and experience in applying emerging ICTs in disseminating agriculture information to farmers and farm communities to improve productivity and economic,social and environmental *** paper reviews and analyzes the development stages of China’s agricultural information dissemination systems and different mechanisms for agricultural information service development and *** ICT-based information dissemination models are identified and *** cases are *** findings provide a useful direction for researchers and practitioners in developing future ICT based information dissemination *** is hoped that this paper will also help other developing countries to learn from China’s experience and best practice in their endeavor of applying emerging ICTs in agriculture information dissemination and knowledge transfer.

关键词： ICT-based information service model China Agriculture Farmers Information dissemination Informatization