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VisQAC: Visual Analytics for Online Q&A Communities

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Journal of Beijing Institute of Technology 2019年第2期28卷 305-317页

作者： Jing Liang Ruoyu Jia Min Zhu henry B L Duh School of Computer Science Sichuan UniversityChengdu 610065China Department of Computer Science and Information Technology La Trobe UniversityMelbourne 3086Australia

Online question and answer(Q&A)communities,which allow users to exchange knowledge by asking and answering questions,have become increasingly *** a result of user active participation,these communities store overwhelming volumes of ***,existing related methods are unable to meet community operators’needs for analyzing multi-dimensional Q&A sequences and understanding user *** this paper,collaborating with domain experts in online community,we present a system,VisQAC,which explores the patterns of Q&A sequence and user *** the system,a novel visual design is proposed,which is combined with flexible mapping measures for analyzing critical characteristics of sequence ***,a timeline visualization method is designed to visualize data with categorical attributes and its correlation can be displayed flexibly by choosing time mode and time *** usefulness and effectiveness of the system are demonstrated with several case studies of VisQAC with community operators based on the Zhihu *** evaluation shows that VisQAC is beneficial to the understanding of Q&A sequence and associated user behavior.

关键词： online Q&A community visual analytics sequence data user behavior

Numerical investigation of the dynamics of a rigidspherical particle in a vortical cross-slot flow atmoderate inertia

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Microsystems & Nanoengineering 2023年第4期9卷 181-195页

作者： Konstantinos Kechagidis Benjamin Owen Lionel Guillou henry Tse Dino Di Carlo Timm Krüger School of Engineering Institute for Multiscale ThermofluidsUniversity of EdinburghW Mains RdEdinburgh EH93JW ScotlandUK Cytovale Inc.Executive Park Blvd.San Fransisco CA 90095 CAUSA Department of Bioengineering University of CaliforniaWestwood PlazaLos Angeles 610101 CAUSA

The study of flow and particle dynamics in microfluidic cross-slot channels is of high relevance for lab-on-a-chipapplications. In this work, we investigate the dynamics of a rigid spherical particle in a cross-slot junction for a channelheight-to-width ratio of 0.6 and at a Reynolds number of 120 for which a steady vortex exists in the junction *** an in-house immersed-boundary-lattice-Boltzmann code, we analyse the effect of the entry position of theparticle in the junction and the particle size on the dynamics and trajectory shape of the particle. We find that thedynamics of the particle depend strongly on its lateral entry position in the junction and weakly on its vertical entryposition;particles that enter close to the centre show trajectory oscillations. Larger particles have longer residencetimes in the junction and tend to oscillate less due to their confinement. Our work contributes to the understanding ofparticle dynamics in intersecting flows and enables the design of optimised geometries for cytometry and particlemanipulation.

关键词： particle dynamics spherical

Design and application of the method for isolating magnetotactic bacteria

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Chinese Journal Of Geochemistry 2007年第3期26卷 252-258页

作者： XIAO Zhijie LIAN Bin CHEN Jun H. henry Teng Jiangsu Key Laboratory for Biodlverslty and Blotechnology College of Biologlcal Sciences Nanjing Normal University Nanjing 210097 China Institute of Surficial Geochemistry. Department of Earth Sciences Nanjing University Nanjing 210093 China Department of Chemlstry the George Washington University Washington DC 20052. USA

A simple apparatus was designed to effectively isolate magnetotactic bacteria from soils or sediments based on their magnetotaxis. Through a series of processes including sample incubation, MTB harvesting, isolation, purification and identification, several strains of bacteria were isolated from the samples successfully. By Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray Analysis (EDXA), these bacteria were certificated to be magnetotactic bacteria. The phylogenetic relationship between the isolated magnetic strains and some known magnetotactic bacteria was inferred by the construction of phylogenetic tree based on 16SrDNA sequences. This apparatus has been proven to have the advantages of being inexpensive, simple to assemble, easy to perform and highly efficient to isolate novel magnetotactic bacteria. The research indicated that the combined approach of harvesting MTB by home-made apparatus and the method of plate colony isolation could purify and isolate magnetotactic bacteria effectively.

关键词：趋磁性隔离带器械化学成分

Efficient search of compositional space for hybrid organic-inorganic perovskites via Bayesian optimization

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npj Computational Materials 2018年第1期4卷 232-238页

作者： henry C.Herbol Weici Hu Peter Frazier Paulette Clancy Matthias Poloczek Department of Materials Science and Engineering Cornell UniversityIthacaNYUSA School of Operations Research and Information Engineering Cornell UniversityIthacaNYUSA Robert F.Smith School of Chemical and Biomolecular Engineering Cornell UniversityIthacaNYUSA Department of Systems and Industrial Engineering University of ArizonaTucsonAZUSA

Accelerated searches,made possible by machine learning techniques,are of growing interest in materials discovery.A suitable case involves the solution processing of components that ultimately form thin films of solar cell materials known as hybrid organic–inorganic perovskites(HOIPs).The number of molecular species that combine in solution to form these films constitutes an overwhelmingly large“compositional”space(at times,exceeding 500,000 possible combinations).Selecting a HOIP with desirable characteristics involves choosing different cations,halides,and solvent blends from a diverse palette of *** unguided search by experimental investigations or molecular simulations is prohibitively *** this work,we propose a Bayesian optimization method that uses an application-specific kernel to overcome challenges where data is scarce,and in which the search space is given by binary variables indicating whether a constituent is present or *** demonstrate that the proposed approach identifies HOIPs with the targeted maximum intermolecular binding energy between HOIP salt and solvent at considerably lower cost than previous state-of-the-art Bayesian optimization methodology and at a fraction of the time(less than 10%)needed to complete an exhaustive *** find an optimal composition within 15±10 iterations in a HOIP compositional space containing 72 combinations,and within 31±9 iterations when considering mixed halides(240 combinations).Exhaustive quantum mechanical simulations of all possible combinations were used to validate the optimal prediction from a Bayesian optimization *** paper demonstrates the potential of the Bayesian optimization methodology reported here for new materials discovery.

关键词： optimization inorganic perovskite

Survey of E-Commerce Modeling and Optimization Strategies

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Tsinghua Science and Technology 2005年第z1期10卷 761-771页

作者： WANG Dingwei NUTTLE henry L.W. FANG Shu-Cherng School of Information Science and Engineering Northeastern University Shenyang 110004 China Department of Industrial Engineering North Carolina State University Raleigh NC 27695 USA Department of Industrial Engineering North Carolina State University Raleigh NC 27695 USA

Electronic commerce is impacting almost all commercial activities. The resulting emerging commercial activities bring with them many new modeling and optimization problems. This survey reviews pioneering works in this new area, covering topics in advertising strategy, web page design, automatic pricing, auction methods, brokerage strategy, and customer behavior analysis. Mathematical models for problems in these areas and their solution algorithms are discussed. In addition to presenting and commenting on these works, we also discuss possible extensions and related problems. The objective of this survey is to encourage more researchers to pay attention to this emerging area.

关键词： electronic commerce modeling and optimization advertising web link pricing auction brokerage customer behavior

Energy expenditure and muscular activation patterns through active sitting on compliant surfaces

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Journal of Sport and Health Science 2017年第2期6卷 207-212页

作者： D.Clark Dickin Rachel K.Surowiec henry Wang Biomechanics Laboratory Ball State UniversityMuncieIN 47306USA

Purpose: To test the effectiveness of sitting surfaces with varied amounts of stability on muscle activity and energy ***: Using a within-participants repeated measures design, 11 healthy young-adult females(age = 20.0 ± 1.8 years) were measured using indirect calorimetry to assess energy expenditure, and electromyography to assess muscular activation in trunk and leg musculature under 3different sitting surfaces: flat-firm surface, air-filled cushion, and a stability ball. Data were analyzed using repeated measures analysis of variance with follow-up pairwise contrasts used to determine the specific effects of sitting surface on muscle activation and energy ***: Significantly greater energy expenditure was recorded for the stability ball(p = 0.01) and the cushion(p = 0.03) over the flat surface(10.4% and 9.6% greater, respectively), with no differences between the ball and the cushion. Both the ball and the cushion produced higher tibialis anterior activation over the flat surface(1.09 and 0.63 root-mean-square millivolts(RMSmv), respectively), while the stability ball produced higher soleus activity over both cushion and flat surfaces(3.97 and 4.24 RMSmv, respectively). Additionally, the cushion elicited higher adductor longus activity over the ball and flat surfaces(1.76 and 1.81 RMSmv, respectively), but no trunk musculature differences were ***: Compliant surfaces resulted in higher levels of muscular activation in the lower extremities facilitating increased caloric *** the increasing trends in sedentary careers and the increases in obesity, this is an important finding to validate the merits of active sitting facilitating increased caloric expenditure and muscle activation.

关键词： Energy metabolism Electromyography Female Posture Sedentary lifestyle Workplace

An infinite-dimensional model of liquidity in financial markets

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Probability, Uncertainty and Quantitative Risk 2021年第2期6卷 117-138页

作者： Sergey V Lototsky henry Schellhorn Ran Zhao Department of Mathematics University of Southern CaliforniaLos AngelesCA 90089USA Institute of Mathematical Sciences Claremont Graduate UniversityClaremontCA 91711USA Drucker School of Management Claremont Graduate UniversityClaremontCA 91711USA

We consider a dynamic market model of liquidity where unmatched buy and sell limit orders are stored in order *** resulting net demand surface constitutes the sole input to the *** model demand using a two-parameter Brownian motion because(i)different points on the demand curve correspond to orders motivated by different information,and(ii)in general,the market price of risk equation of no-arbitrage theory has no solutions when the demand curve is driven by a finite number of factors,thus allowing for *** prove that if the driving noise is infinite-dimensional,then there is no arbitrage in the *** the equivalent martingale measure,the clearing price is a martingale,and options can be priced under the no-arbitrage *** consider several parameterizations of the model and show advantages of specifying the demand curve as a quantity that is a function of price,as opposed to price as a function of *** online appendix presents a basic empirical analysis of the model:calibration using information from actual order books,computation of option prices using Monte Carlo simulations,and comparison with observed data.

关键词： Liquidity modeling Brownian sheet Itô-Wentzell formula No-arbitrage condition Stochastic partial differential equations

Potential role of Lycium barbarum polysaccharides in glaucoma management:evidence from preclinical in vivo studies

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Neural Regeneration Research 2023年第12期18卷 2623-2632页

作者： Yamunadevi Lakshmanan Francisca Siu Yin Wong Kwok-Fai So henry Ho-Lung Chan Centre for Eye and Vision Research(CEVR) 17W Hong Kong Science ParkHong Kong Special Administrative RegionChina Guangdong-Hongkong-Macao(GHM)Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina Department of Ophthalmology LKS Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Laboratory of Experimental Optometry(Neuroscience) School of OptometryThe Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Research Centre for SHARP Vision(RCSV) The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina University Research Facilities in Behavioral and Systems Neuroscience(UBSN) The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina

In recent years,the pharmacological benefits of herbal extracts have been revisited for their potential neuroprotective effects in *** polysaccharides extracted from the fruits of Lycium barbarum L.,or Lycium barbarum polysaccharides,exert their anti-aging effect through reducing oxidative stress,modulating the immune response,enhancing neuronal responses,and promoting *** therapeutic efficacy of Lycium barbarum polysaccharides in preserving retinal ganglion cells and their functions was demonstrated in a range of experimental models of optic *** include the acute and chronic ocular hypertension models,the partial optic nerve transection model,and the ischemic-reperfusion injuries *** on these findings,Lycium barbarum polysaccharides appear to be a good candidate to be developed as a neuroprotective agent for treating multifactorial *** review aims to present a comprehensive review on the latest preclinical evidence on the pre-and post-treatment benefits of Lycium barbarum polysaccharides in retinal ganglion cell *** possible mechanisms of Lycium barbarum polysaccharides mediating retinal ganglion cell neuroprotection will also be ***,the potential research gaps in the effective translation of Lycium barbarum polysaccharides treatment into clinical glaucoma management will be discussed.

关键词： animal model complementary and alternative medicine glaucoma retinal ganglion cell Lycium barbarum polysaccharide neuroprotection neuro-rescue ocular hypertension post-treatment pre-treatment

Multi-spacecraft observations of earthward flow bursts

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Science China(Technological Sciences) 2012年第5期55卷 1305-1311页

作者： MA YuDuan CAO JinBin REME henry DANDOURAS Iannis DUNLOP Malcolm LUCEK Elisabeth School of Astronautics Beihang UniversityBeijing 100191China SOA Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China Centre d'Etude Spatiale des Rayonnements Toulouse 31028France RutherforAppleton Laboratory OxfordshireUK Blackett Laboratory Imperial College LondonLondon SW72AZUK

On the basis of the plasma, electric and magnetic fields jointly observed by Cluster and the Double Star TC-I spacecraft in the Earth＇s magnetotail, we have investigated the earthward flow bursts by introducing the momentum equation in the X-direction in the ideal conditions of magneto hydrodynamics （MHD）. One earthward flow burst with a peak in excess of 500 km/s was selected, when the four spacecraft of Cluster were located around -16 RE and TC-1 was located around -10 RE in the X-direction. The inter-spacecraft distances in Y and Z directions were smaller than the statistical spatial scales of the bursty bulk flows. When the Y components of E and -VxB were compared, there was no clear breakdown of the frozen-in condition during the earthward flow burst. With the measured plasma and magnetic parameters from two spacecraft at different positions in the magnetotail, the X component of the pressure gradient was calculated. Magnetic tension was calculated using the mag- netic field measured at four points, which could be compared with the assumed constant in the past research with single satel- lite. When the pressure gradient and the magnetic tension were put into the MHD momentum equation, some samples of the earthward flow bursts were accelerated and some were decelerated. The braking process of the earthward flow burst was more complicated than what the past results had shown. The accelerated samples accounted for about one third of the whole earth- ward flow bursts and discontinuously located among the decelerated elements. The original single earthward flow burst event might be split into several short flow bursts when it was moving to the Earth. Our results may partly illustrate that the duration of fast flows during three phases of substorm becomes short near the Earth. The results are consistent with the past results that fast flows intrude to places earthward the typical braking region.

关键词： flow burst pressure gradient magnetic tension braking