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POINTWISE AND UPWIND DISCRETIZATIONS OF SOURCE TERMS IN OPEN-CHANNEL FLOOD ROUTING

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Journal of Hydrodynamics 2006年第4期18卷 379-386页

作者： MENG Jian cao Zhi-xian CARLING paul A. College of Information Management Wuhan University Wuhan 430072 China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan430072 China School of Geography University of Southampton Highfield SO17 1B J UK

Upwind algorithms are becoming progressively popular for river flood routing due to their capability of resolving trans-critical flow regimes. For consistency, these algorithms suggest natural upwind discretization of the source term, which may be essential for natural channels with irregular geometry. Yet applications of these upwind algorithms to natural river flows are rare, and in such applications the traditional and simpler pointwise, rather than upwind discretization of the source term is used. Within the framework of a first-order upwind algorithm, this paper presents a comparison of upwind and pointwise discretizations of the source term. Numerical simulations were carried out for a selected irregular channel comprising a pool-riffle sequence Jn the River Lune, England with observed data. It is Shown that the impact of pointwise discretization, compared to the upwind, is appreciable mainly in flow zones with the Froude number closer to or larger than unity. The discrepancy due to pointwise and upwind discretizations of the source term is negligible in flow depth and hence in water surface elevation, but well manifested in mean velocity and derived flow quantities. Also the occurrence of flow reversal and equalisation over the pool-riffle sequence in response to increasing discharges is demonstrated.

关键词： St-Venant equations upwind scheme,pointwise discretization source term pool-riffle sequence flow reversal flood routing

Coupled flood and sediment transport modelling with adaptive mesh refinement

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Science China(Technological Sciences) 2015年第8期58卷 1425-1438页

作者： HUANG Wei cao ZhiXian PENDER Gareth LIU QingQuan CARLING paul State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Institute for Infrastructure and Environment Heriot-Watt University Institute of Mechanics Chinese Academy of Sciences Geography & Environment University of Southampton

Coupled flood and sediment transport modelling in large-scale domains has for long been hindered by the high computational *** mesh refinement is one of the viable ways to solving this problem without degrading the *** goal can be accomplished through mesh adaptation,e.g.,mesh coarsening and refining based on the dynamic regime of the flow and sediment transport along with bed ***,previous studies in this regard have been limited to cases either without involving sediment transport or featuring flow-sediment-bed decoupling and the assumption of sediment transport capacity,which are not generally ***,a coupled hydrodynamic and non-capacity sediment transport model is developed on adaptive non-uniform rectangular *** proposed model is validated against experimental tests and numerical results based on the fixed *** is demonstrated that the proposed model can properly capture shock waves,resolve the wetting/drying transition and reproduce morphological *** with models based on the fixed meshes,the proposed model features great advantage in computational efficiency and holds promise for wide applications.

关键词： shallow water flow sediment transport adaptive mesh

Coupled 2D Hydrodynamic and Sediment Transport Modeling of Megaflood due to Glacier Dam-break in Altai Mountains,Southern Siberia

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Journal of Mountain Science 2014年第6期11卷 1442-1453页

作者： HUANG Wei cao Zhi-xian paul CARLING Gareth PENDER State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Institute for Infrastructure and Environment Heriot-Watt University School of Geography University of Southampton

One of the largest known megafloods on earth resulted from a glacier dam-break,which occurred during the Late Quaternary in the Altai Mountains in Southern *** modeling is one of the viable approaches to enhancing the understanding of the flood *** computational domain of this flood is over 9460 km2 and about 3.784 × 106 cells are involved as a 50 m × 50 m mesh is used,which necessitates a computationally efficient *** the Open MP(Open Multiprocessing) technique is adopted to parallelize the code of a coupled 2D hydrodynamic and sediment transport *** is shown that the computational efficiency is enhanced by over 80% due to the *** floods over both fixed and mobile beds are well reproduced with specified discharge hydrographs at the dam ***,backwater effects during the flood are resolved at the bifurcation between the Chuja and Katun ***,the computed maximum stage and thalweg are physically consistent with the field data of the bars and *** effects of sediment transport and morphological evolution on the flood are *** analyses indicate that the impact of the peak discharge is significant,whilst those of the Manningroughness,medium sediment size and shape of the inlet discharge hydrograph are marginal.

关键词： Glacier dam-break flood Well-balanced 2D hydrodynamic and sediment transport model Open MP parallelization

Perspectives of breast cancer etiology: synergistic interaction between smoking and exogenous hormone use

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Chinese Journal of Cancer 2011年第7期30卷 433-441页

作者： Hong-Hong Zhu cao-Hui Hu paul Strickland Department of Epidemiology Johns Hopkins Bloomberg School of Public Health Baltimore MD 21205 USA Division of Epidemiology Department of Community Health Saint Louis University School of Public Health St Louis MO 63104 USA Department of Endocrinology Quzhou People's First Hospital Quzhou Zhejiang 324000 P. R. China Department of Environmental Health Sciences Johns Hopkins Bloomberg School of Public Health Baltimore MD 21205 USA.

To explore breast cancer etiology, literature was searched using Medline. We explored the (1) plausibility of smoking in breast carcinogenesis; (2) physiological properties, susceptibility windows, and exposure timing of breast cells; (3) role of exogenous hormones in breast carcinogenesis; (4) biological mechanism of synergistic interactions between smoking and exogenous hormones in breast carcinogenesis; and (5) evidence from epidemiologic studies and the fitted secular trend between smoking rate, exogenous hormone use, and breast cancer incidence in past decades. We deduced that exogenous hormone use per se is not a significant cause and its association with breast cancer is distorted by chronic exposure to environmental carcinogens, especially smoking. We hypothesize that smoking is one of the causes of breast cancer and that this causality is strengthened by synergistic interaction between smoking and exogenous hormone use. Physicians should be cautious of prescribing exogenous hormones for those with chronic exposure to environmental carcinogens to prevent breast cancer.

关键词：外源激素协同作用乳腺癌吸烟率病因 Windows 致癌物质致癌作用

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Eye and Vision 2019年第1期6卷 322-330页

作者： Ke cao Srujana Sahebjada Andrea J.Richardson paul N.Baird Centre for Eye Research Australia Royal Victorian Eye and Ear HospitalMelbourneAustralia. Department of Surgery OphthalmologyThe University of Melbourne32 Gisborne StreetEast MelbourneVIC 3000Australia

Background:Keratoconus(KC)is a common corneal condition with an unknown gender *** numerous studies have investigated the genetic component of KC,no specific genes have yet been attributed to the *** recently reported posterior segment changes occurring in the eyes of KC ***,it is not clear whether these changes are part of KC pathogenesis or reflect changes in anatomical features of the eye manifested by changes at the *** retinal changes represent the main characteristics observed in agerelated macular degeneration(AMD)and that pleiotropy has been demonstrated between different eye diseases,we wished to assess if known AMD associated genes were also associated with ***:A total of 248 KC subjects and 366 non-KC(control)subjects were recruited from public and private clinics in Melbourne for this *** single nucleotide polymorphisms(SNPs)previously associated with AMD,including rs10490924(ARMS2/HTRA1),rs10737680(CFH),rs13278062(TNFRSF10A),rs1864163(CETP),rs2230199(C3),rs3130783(IER3/DDR1),rs334353(TGFBR1),rs3812111(COL10A1),rs429608(C2/CFB),rs4420638(APOE),rs4698775(CFI),rs5749482(TIMP3),rs6795735(ADAMTS9),rs8017304(RAD51B),rs8135665(SLC16A8),rs920915(LIPC),rs943080(VEGFA),rs9542236(B3GALTL)and rs13081855(COL8A1/FILIP1L),were genotyped in this *** regression was applied to evaluate the association between these SNPs and KC on both genders together,as well as each gender *** regression was also applied to assess the association between SNPs and corneal *** correction was applied to adjust for multiple ***:Genotyping data were available for 18 *** SNP,rs6795735(ADAMTS9)was significantly associated with KC(p=3.5×10−4)when both genders were assessed,whereas rs5749482(TIMP3)was only associated in males(p=7.7×10−4)following Bonferroni multiple ***,when the covariates of age and gender were included,the associations became non-sign

关键词： Keratoconus Gender Genetic Age-related macular degeneration

AI for science: Predicting infectious diseases

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Journal of Safety Science and Resilience 2024年第2期5卷 130-146页

作者： Alexis Pengfei Zhao Shuangqi Li Zhidong cao paul Jen-Hwa Hu Jiaojiao Wang Yue Xiang Da Xie Xi Lu Institute of Automation Chinese Academy of SciencesUniversity of Chinese Academy of SciencesBejing 100090China Systems Engineering Cornll UniversityIthacaNY 14853USA David Eccles School of Business the University of UtahUtahUSA Collge of Electrical Engineering Sichuan UniversityChina Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering Southeast UniversityNanjing 210096China

The global health landscape has been persistently challenged by the emergence and re-emergence of infectious *** epidemiological models,rooted in the early 2oth century,have provided foundational in-sights into disease ***,the intricate web of modern global interactions and the exponential growth of available data demand more advanced predictive *** is where AI for Science(AI4S)comes into play,offering a transformative approach by integrating artificial intelligence(Al)into infectious disease *** paper elucidates the pivotal role of AI4s in enhancing and,in some instances,superseding tradi-tional epidemiological *** harnessing AI's capabilities,AI4S facilitates real-time monitoring,sophisticated data integration,and predictive modeling with enhanced *** comparative analysis highlights the stark contrast between conventional models and the innovative strategies enabled by *** essence,Al4S represents a paradigm shift in infectious disease *** addresses the limitations of traditional models and paves the way for a more proactive and informed response to future *** we navigate the complexities of global health challenges,Al4S stands as a beacon,signifying the next phase of evolution in disease prediction,characterized by increased accuracy,adaptability,and efficiency.

关键词： AI for science(AI4S) Data integration Global healthchallenges Infectious disease prediction Predictive modeling Real-timemonitoring

A social computing method for energy safety

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Journal of Safety Science and Resilience 2024年第1期5卷 64-82页

作者： Pengfei Zhao Shuangqi Li Zhidong cao paul Jen-Hwa Hu Daniel Dajun Zeng Da Xie Yichen Shen Jiangfeng Li Tianyi Luo Institute of Automation Chinese Academy of SciencesUniversity of Chinese Academy of SciencesBeijing 100090China Systems Engineering Cornell UniversityIthacaNY 14853USA David Eccles School of Business the University of UtahUtahUSA Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China China University of Mining and Technology China

Information and communication technologies enable the transformation of traditional energy systems into cyber-physical energy systems(CPESs),but such systems have also become popular targets of ***,available methods for evaluating the impacts of cyberattacks suffer from limited resilience,efficacy,and practical *** mitigate their potentially disastrous consequences,this study suggests a two-stage,discrepancy-based optimization approach that considers both preparatory actions and response measures,integrating concepts from social *** proposed Kullback-Leibler divergence-based,distributionally robust optimization(KDR)method has a hierarchical,two-stage objective function that incorporates the operating costs of both system infrastructures(e.g.,energy resources,reserve capacity)and real-time response measures(e.g.,load shedding,demand-side management,electric vehicle charging station management).By incorporating social computing principles,the optimization framework can also capture the social behavior and interactions of energy consumers in response to *** preparatory stage entails day-ahead operational decisions,leveraging insights from social computing to model and predict the behaviors of individuals and communities affected by potential *** mitigation stage generates responses designed to contain the consequences of the attack by directing and optimizing energy use from the demand side,taking into account the social context and preferences of energy consumers,to ensure resilient,economically efficient CPES *** method can determine optimal schemes in both stages,accounting for the social dimensions of the *** original disaster mitigation model uses an abstract formulation to develop a risk-neutral model that characterizes cyberattacks through KDR,incorporating social computing techniques to enhance the understanding and response to cyber *** approach can mitigate the impacts more

关键词： Cyberattacks Cyber-physical energy systems Distributionally robust optimization False data injections Two-stage modeling Social computing

Iron in the NEEM ice core relative to Asian loess records over the last glacial–interglacial cycle

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National Science Review 2021年第7期8卷 110-123页

作者： Cunde Xiao Zhiheng Du Mike J Handley paul A Mayewski Junji cao Simon Schupbach Tong Zhang Jean-Robert Petit Chuanjin Li Yeongcheol Han Yuefang Li Jiawen Ren State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Climate Change Institute School of Earth and Climate Sciences University of Maine Key Laboratory of Aerosol Science and Technology SKLLQG Institute of Earth Environment Chinese Academy of Sciences Climate and Environmental Physics Physics Institute University of Bern 6. Institute of Tibetan Plateau and Polar Meteorology Chinese Academy of Meteorological Sciences 7. Institut des Geosciences de I'Environment (IGE) University Grenoble Alpes 8. Korea Polar Research Institute

Mineral dust can indirectly affect the climate by supplying bioavailable iron(Fe) to the ocean. Here, we present the records of dissolved Fe(DFe) and total Fe(TDFe) in North Greenland Eemian Ice Drilling(NEEM) ice core over the past 110 kyr BP. The Fe records are significantly negatively correlated with the carbon-dioxide(CO2) concentrations during cold periods. The results suggest that the changes in Fe fluxes over the past 110 kyr BP in the NEEM ice core are consistent with those in Chinese loess records because the mineral-dust distribution is controlled by the East Asian deserts. Furthermore, the variations in the dust input on a global scale are most likely driven by changes in solar radiation during the last glacial–interglacial cycle in response to Earth’s orbital cycles. In the last glacial–interglacial cycle, the DFe/TDFe ratios were higher during the warm periods(following the post-Industrial Revolution and during the Holocene and last interglacial period) than during the main cold period(i.e. the last glacial maximum(LGM)), indicating that the aeolian input of iron and the iron fertilization effect on the oceans have a non-linear relationship during different periods. Although the burning of biomass aerosols has released large amounts of DFe since the Industrial Revolution, no significant responses are observed in the DFe and TDFe variations during this period, indicating that severe anthropogenic contamination has no significant effect on the DFe(TDFe)release in the NEEM ice core.

关键词： Greenland NEEM ice core iron fertilization carbon dioxide Chinese loess glacial–interglacial cycle

Identification of Chinese drug Taraxaci Herba and Its adulterants by LM/SEM observation

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Identification of Chinese drug Taraxaci Herba and Its adulte...