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Model updating based on incomplete modal data

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Science China(Technological Sciences) 2011年第7期54卷 1737-1747页

作者： LI huaJun WANG JunRong hu Sau-Lon james Shandong Provincial Key Lab of Ocean Engineering Ocean University of China Qingdao 266100 China CNOOC Research Institute China National Offshore Oil Corporation Beijing 100027 China Department of Ocean Engineering University of Rhode Island Narragansett RI 02882-1197 USA

The objective of model updating is to improve the accuracy of a dynamic model based on the correlation between the measured data and the analytical (finite element) model. In this paper, we intend to update the mass and stiffness matrices of an analytical model when only modal frequencies or spatially incomplete modal data are available. While the proposed method is systematic in nature, it also preserves the initial configuration of the analytical model, and physical equality and/or inequality constraints can be easily incorporated into the solution procedure. Numerical examples associated with a simple 5-DoF (degree of freedom) mass-spring system are chosen to illustrate the detailed procedure and the effectiveness of the proposed method. Numerical scenarios ranging from the updating for stiffness terms only to that for all mass and stiffness terms based on various kinds of incomplete modal data are studied. The obtained model updating results are excellent when the measured modal data are noise-free. Uncertainty studies are also conducted based on simulations of corrupted modal data, but a thorough theoretical analysis of the noise effect on the proposed method is still needed.

关键词： model updating model reduction modal expansion incomplete mode

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辽宁省高速公路生态景观评价体系构建

沈阳建筑大学学报（社会科学版） 2017年第3期19卷 245-251页

作者：朱玲詹姆斯.希契莫夫胡振国苏兰兰沈阳建筑大学建筑与规划学院辽宁沈阳110168 谢菲尔德大学景观学院

阐述了高速公路生态景观评价指标的建设方法,通过层次分析法、专家咨询法及目标法相结合对高速公路生态景观进行评价,分析评价了其社会、环境和经济效益,形成指标数据,构建了高速公路生态景观评价指标体系,并以辽宁省长深高速公路阜新... 详细信息

阐述了高速公路生态景观评价指标的建设方法,通过层次分析法、专家咨询法及目标法相结合对高速公路生态景观进行评价,分析评价了其社会、环境和经济效益,形成指标数据,构建了高速公路生态景观评价指标体系,并以辽宁省长深高速公路阜新挖方段绿化为例进行了生态景观评价。

关键词：高速公路生态景观评价体系构建长深高速公路阜新挖方段

Bird guild loss and its determinants on subtropical land-bridge islands, China

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Chinese Birds 2015年第2期6卷 99-106页

作者： Zhifeng Ding Kenneth james Feeley huijian hu Ping Ding The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education College of Life Sciences Zhejiang UniversityZijin’gang Campus Guangdong Entomological Institute & South China Institute of Endangered Animals Department of Biological Sciences Florida International University Center for Tropical Plant Conservation Fairchild Tropical Botanic Garden

Background: The guild concept is useful for understanding the community structure in a land-bridge island system,but most fragmentation studies have focused only on the importance of island area and isolation, other island attributes such as perimeter-area ratio(PAR) were overlooked or ***: We have adopted a guild approach to investigate the impacts of island attributes on bird guild richness on a set of 41 recently isolated land-bridge islands in the Thousand Island Lake(TIL), ***: We found insectivores had the largest number of species(34 species), fol owed by understory foraging guilds(28 species), omnivores(27 species) and canopy guilds(25 species). Furthermore, our data showed that migrants and residents responded equal y to island area, insectivores and understory guilds were sensitive to island area but omnivores and canopy guilds were not very sensitive. Most guild richness was determined by island area, except for omnivores and canopy ***: Although PAR or habitat diversity found to be important for bird species richness, our results highlight the importance of island area in maintaining bird diversity in fragmented island systems.

关键词： Bird guilds Island area Land-bridge islands PAR Thousand Island Lake z values

Stress Wave Propagation Analysis on Vortex-Induced Vibration of Marine Risers

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China Ocean Engineering 2017年第1期31卷 30-36页

作者： LI hua-jun WANG Chao LIU Fu-shun hu Sau-Lon james Shandong Provincial Key Lab of Ocean Engineering Ocean University of China Department of Ocean Engineering University of Rhode Island

To analyze the stress wave propagation associated with the vortex-induced vibration（VIV） of a marine riser, this paper employed a multi-signal complex exponential method. This method is an extension of the classical Prony＇s method which decomposes a complicated signal into a number of complex exponential components. Because the proposed method processes multiple signals simultaneously, it can estimate the “global” dominating frequencies（poles） shared by those *** complex amplitude（residues） corresponding to the estimated frequencies for those signals is also obtained in the process. As the signals were collected at different locations along the axial direction of a marine riser, the phenomena of the stress wave propagation could be analyzed through the obtained residues of those signals. The Norwegian Deepwater Program（NDP） high mode test data were utilized in the numerical studies, including data sets in both the in-line（IL） and cross-flow（CF） directions. It was found that the most dominant component in the IL direction has its stress wave propagation along the riser being dominated by a standing wave, while that in the CF direction dominated by a traveling wave.

关键词： Vortex exponential utilized reconstructed riser directions interpolation dominated residues processed

A post-classical theory of enamel biomineralization… and why we need one

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International Journal of Oral Science 2012年第3期4卷 129-134页

作者： james P Simmer Amelia S Richardson Yuan-Yuan hu Charles E Smith Jan Ching-Chun hu Department of Biologic and Materials Sciences School of Dentistry University of Michigan Ann Arbor USA Facility for Electron Microscopy Research Department of Anatomy and CellBiology and Faculty ofDentstry McGlIUniversity. Montreal Canada

Enamel crystals are unique in shape, orientation and organization. They are hundreds of thousands times longer than they are wide, run parallel to each other, are oriented with respect to the ameloblast membrane at the mineralization front and are organized into rod or interrod enamel. The classical theory of amelogenesis postulates that extracellular matrix proteins shape crystallites by specifically inhibiting ion deposition on the crystal sides, orient them by binding multiple crystallites and establish higher levels of crystal organization. Elements of the classical theory are supported in principle by in vitro studies; however, the classical theory does not explain how enamel forms in vivo. In this review, we describe how amelogenesis is highly integrated with ameloblast cell activities and how the shape, orientation and organization of enamel mineral ribbons are established by a mineralization front apparatus along the secretory surface of the ameloblast cell membrane.

关键词： ameloblastin amelogenin enamelin mineralization front tooth

Coupling virio-and bacterioplankton populations with environmental variable changes in the Bohai Sea

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Acta Oceanologica Sinica 2020年第6期39卷 72-83页

作者： Caixia Wang Lin Wu Yibo Wang james S.Paterson james G.Mitchell Xiaoke hu Key Laboratory of Coastal Biology and Bioresource Utilization Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Ocean School Yantai UniversityYantai 264003China College of Science and Engineering Flinders UniversityAdelaideSA 5001Australia

Uncovering the role of environmental factors and finding critical factors which harbor significant fractions in governing microbial communities remain key questions in coastal marine *** detect the interactions between environmental factors and distributions of virio-and bacterioplankton in trophic coastal areas,we used flow cytometry to investigate the abundance of virio-and bacterioplankton covering 31 stations in the Bohai Sea of *** results suggested that the average abundance of total virus(TV)in winter(~2.29×108 particles/mL)was slightly lower than in summer(~3.83×108 particles/mL).The mean total bacterial abundance(TB)was much lower in winter(~2.54×107 particles/mL)than in summer(~5.43×107 particles/mL).Correlation analysis via redundancy analysis(RDA)and network analysis among virioplankton,bacterioplankton and environmental factors revealed that the abundances of viral and bacterial subpopulations depend on environmental *** winter,only temperature significantly influenced the abundances of virio-and *** summer,in addition to temperature,both salinity and nutrient(SiO2)had a remarkable impact on the distribution of virioand *** results showed a clear seasonal and trophic pattern throughout the whole water system,which revealed that temperature and eutrophication may play crucial roles in microbial distribution pattern.

关键词： virioplankton bacterioplankton flow cytometry network Bohai Sea

Simulation study of huff-n-puff air injection for enhanced oil recovery in shale oil reservoirs

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Petroleum 2018年第1期4卷 7-14页

作者： hu Jia james J.Sheng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan 610500China Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX 79409USA

This paper is the first attempt to evaluate huff-n-puff air injection in a shale oil reservoir using a simulation *** mechanisms and physical processes of huff-n-puff air injection in a shale oil reservoir are investigated through investigating production performance,thermal behavior,reservoir pressure and fluid saturation *** flooding is used as the basic case for a comparative *** simulation study suggests that thermal drive is the main recovery mechanism for huff-n-puff air injection in the shale oil reservoir,but not for simple air *** synergic recovery mechanism of air flooding in conventional light oil reservoirs can be replicated in shale oil reservoirs by using air huff-npuff injection *** huff-n-puff time is better for performing the synergic recovery mechanism of air injection.O2 diffusion plays an important role in huff-n-puff air injection in shale oil *** transmissibility as well as reservoir pressure maintenance ability in huff-n-puff air injection is more pronounced than the simple air flooding after primary depletion *** obvious gas override is exhibited in both air flooding and air huff-n-puff injection scenarios in shale ***-puff air injection has great potential to develop shale oil *** results from this work may stimulate further investigations.

关键词： Air injection huff-n-puff Shale reservoirs Unconventional Air flooding Enhanced oil recovery

Discussion of the feasibility of air injection for enhanced oil recovery in shale oil reservoirs

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Petroleum 2017年第2期3卷 249-257页

作者： hu Jia james J.Sheng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduSichuan610500China Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX 79409USA

Air injection in light oil reservoirs has received considerable attention as an effective,improved oil recovery process,based primarily on the success of several projects within the Williston Basin in the United *** main mechanism of air injection is the oxidation behavior between oxygen and crude oil in the *** injection is a good option because of its wide availability and low *** air injection can be applied to shale is an interesting topic from both economic and technical *** paper initiates a comprehensive discussion on the feasibility and potential of air injection in shale oil reservoirs based on state-of-the-art literature *** and unfavorable effects of using air injection are discussed in an analogy analysis on geology,reservoir features,temperature,pressure,and petrophysical,mineral and crude oil properties of shale oil *** available data comparison of the historically successful air injection projects with typical shale oil reservoirs in the *** summarized in this *** operation methods to improve air injection performance are *** paper provides an avenue for us to make use of many of the favorable conditions of shale oil reservoirs for implementing air injection,or air huff‘n’puff injection,and the low cost of air has the potential to improve oil recovery in shale oil *** analysis may stimulate further investigation.

关键词： shale reservoirs reservoir

Rattle-Type Silica Colloidal Particles Prepared by a Surface- Protected Etching Process

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Nano Research 2009年第7期2卷 583-591页

作者： Qiao Zhang Jianping Ge james Goebl Yongxing hu Zhenda Lu Yadong Yin Department of Chemistry University of CaliforniaRiversideCalifornia 92521USA

This paper explores the capability of the“surface-protected etching”process for the creation of rattle-type SiO_(2)@void@SiO_(2) colloidal structures featuring a mesoporous silica shell and a mesoporous movable silica *** surface-protected etching process involves stabilization of the particle surface using a polymer ligand,and then selective etching of the interior to form hollow *** this paper,this strategy has been extended to the formation of rattle-like structures by etching SiO_(2)@SiO_(2) core shell particles which are synthesized by a two-step sol gel *** key is to introduce a protecting polymer of polyvinylpyrrolidone(PVP)to the surface of both core and shell in order to tailor their relative stability against chemical *** reacting with NaOH,the outer layer silica becomes a hollow shell as only the surface layer is protected by PVP and the interior is removed,while the core remains its original size thanks to the protection of PVP on its *** process can be carried out at room temperature without the need of additional templates or complicated heterogeneous coating *** etching process also results in the rattle-type colloids having mesoscale pores with two distinct average *** our demonstration of a model drug delivery process,such mesoporous structures show an interesting two-step elution profile which is believed to be related to the unique porous rattle structures.

关键词： Silica mesoporous core-shell structure surface-protected etching drug delivery