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Simulation of Horizontal-Two-Dimension Focused Waves Using A Two-Layer Boussinesq-Type Model

China Ocean Engineering 2023年第5期37卷 725-737页

作者： ZOU Wen-feng WANG Ping LIU Zhong-bo fang ke-zhao SUN Jia-wen ZHANG Ning-chuan key Laboratory of coastal and offshore engineering Dalian University of TechnologyDalian 116024China State Environmental Protection key Laboratory of Marine Ecosystem Restoration National Marine Environmental Monitoring CenterDalian 116023China Dalian Maritime University College of Transportation EngineeringDalian 116024China

Accurate simulation of the horizontal-two-dimension(H2D)focused wave group in deep water requires high accuracy of a numerical model.The two-layer Boussinesq-type model(Liu and fang,2016;Liu et al.,2018)with the highest spatial derivative of 2 has high accuracy in both linear and nonlinear properties.Based on the further development of the velocity equations(Liu et al.,2023),the H2D numerical model for water waves is established with the prediction-correction-iteration model in the finite difference method,and a composite fourth-order Adams-Bashforth-Moulton scheme is used for time integration.The wave generation method proposed by Hsiao et al.(2005)is applied and calibrated in this H2D model.The numerical calculations lead to the following three main conclusions:First,compared with the analytical solution of Stokes linear waves,the calculated velocity profiles show higher accuracy by using the improved velocity formulas.Second,the simulations of the focused multidirectional wave group are carried out,and good agreements are found,demonstrating that the present H2D numerical model shows high accuracy in simulating focused multidirectional wave groups,and the effectiveness of the improved velocity formulas is also validated.Furthermore,the velocity profiles throughout the computational domain at the time of maximum wave crest are given.Finally,the FFT method is used to obtain the amplitude with different frequencies for several locations,and the changes of the wavelet energy spectrum at different locations are presented for several cases.

关键词： focused wave horizontal-two-dimension model finite difference method nonlinear property

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适合渗透海床波浪运动的三维Boussinesq型方程

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船舶力学 2024年第5期28卷 697-704页

作者：刘忠波韩沛秀房克照刘勇大连海事大学交通运输工程学院辽宁大连116026 大连理工大学海岸和近海工程国家重点实验室辽宁大连116024 中国海洋大学工程学院山东青岛266000

为考虑孔隙介质对波浪传播变形带来的衰减效应,在渗透介质流体的控制方程中引入线性阻力、非线性阻力和惯性力。自由表面采用精确的运动学和动力学边界条件,水底边界条件采用精确的动力学边界条件,自由水体和渗透介质水体之间满足垂向... 详细信息

为考虑孔隙介质对波浪传播变形带来的衰减效应,在渗透介质流体的控制方程中引入线性阻力、非线性阻力和惯性力。自由表面采用精确的运动学和动力学边界条件,水底边界条件采用精确的动力学边界条件,自由水体和渗透介质水体之间满足垂向速度连续、水平速度满足动量相等条件。首先推导最高空间导数为3的以两组计算速度表达的适合单层渗透海床波浪运动的三维Boussinesq型水波方程。其次,对新给出的方程进行傅里叶分析,并将方程的相速度及衰减率与Stokes线性波的解析解进行比较。在1%误差下,相对水深h_(2)/h_(1)=0.1~10,方程的解析解在无因次水深h_(1)/Lkes线性波的解析解都有较好的吻合,这超过了历史文献中任一个Boussinesq型水波方程的适用范围。进而建立立面二维水槽数值模型,并利用预报-校正-迭代的有限差分方法对数值模型进行求解,在变量对时间的导数求解中选择混合四阶AdamsBashforth-Moulton格式。最后,利用数值模拟再现波浪在渗透地形上的传播变形,并与相关试验结果进行比较,二者吻合程度较高。

关键词：渗透地形衰减率相速度数值模型

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Qualitative Description of Swashing Motion States on Mild Beach Slope

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China Ocean Engineering 2019年第4期33卷 412-423页

作者： YIN Jing ZOU Zhi-li fang ke-zhao LIU Yan-li State key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China key Laboratory of Sea-Area Management Technology National Marine Environmental Monitoring Center Dalian 116024 China

The swashing motion on mild beach slope is dominated by the motion of low frequency waves (LFWs). Companying such a motion, there are two types of swashing motion states, occurrence or no occurrence of LFW’s collision. The present study distinguishes the two states qualitatively by relating it to the number of generated LFWs for the case of two incident wave groups. A simplified swashing index is established theoretically for this purpose. A series of related experiments were performed to observe the generated out-going LFWs on different mild slope from 1:20 to 1:160 and to determine the critical value of the swashing index. Numerical simulations based on higher order Boussinesq equations are also performed to help the recognition of the LFWs generated in the experiment.

关键词： swashing surf beat braking wave low frequency wave wave groups

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BOUSSINESQ MODELLING OF NEARSHORE WAVES UNDER BODY FITTED COORDINATE

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Journal of Hydrodynamics 2012年第2期24卷 235-243页

作者： fang ke-zhao ZOU Zhi-li LIU Zhong-bo YIN Ji-wei State key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024China key Laboratory of Coastal Disaster and Defence Ministry of Eduoation Hohai University Nanjing 210098China E-mail： kfang@***

A set of nonlinear Boussinesq equations with fully nonlinearity property is solved numerically in generalized coordinates,to develop a Boussinesq-type wave model in dealing with irregular computation boundaries in complex nearshore regions and to facilitate the grid refinements in simulations.The governing equations expressed in contravariant components of velocity vectors under curvilinear coordinates are derived and a high order finite difference scheme on a staggered grid is employed for the numerical implementation.The developed model is used to simulate nearshore wave propagations under curvilinear coordinates,the numerical results are compared against analytical or experimental data with a good agreement.

关键词： Boussinesq equation waves body fitted coordinate

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Effect of the Coefficient on the Performance of A Two-Layer Boussinesq- Type Model

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China Ocean Engineering 2021年第1期35卷 36-47页

作者： SUN Jia-wen LIU Zhong-bo WANG Xing-gang fang ke-zhao DU Xin-yuan WANG Ping State Environmental Protection key Laboratory of Marine Ecosystem Restoration National Marine Environmental Monitoring CenterDalian 116023China Transportation Engineering College Dalian Maritime UniversityDalian 116026China Nanjing Hydraulic Research Institute Nanjing 210029China State key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Liaoning natural resources Affairs Service Center Shenyang 110032China

The coefficients embodied in a Boussinesq-type model are very important since they are determined to optimize the linear and nonlinear properties.In most conventional Boussinesq-type models,these coefficients are assigned the specific values.As for the multi-layer Boussinesq-type models with the inclusion of the vertical velocity,however,the effect of the different values of these coefficients on linear and nonlinear performances has never been investigated yet.The present study focuses on a two-layer Boussinesq-type model with the highest spatial derivatives being 2 and theoretically and numerically examines the effect of the coefficient on model performance.Theoretical analysis show that different values for(0.13≤α≤0.25)do not have great effects on the high accuracy of the linear shoaling,linear phase celerity and even third-order nonlinearity for water depth range of 0

关键词： two-layer Boussinesq-type model dispersion nonlinear properties shoaling amplitude

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A risk assessment method considering risk attributes and work safety informational needs and its application

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Chinese Journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： Cong Luo Yunsheng zhao ke Xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and systematicness.Risk assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety management.The study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety management.The methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk factors.Subsequently,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision needs.And in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety management.The findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system

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Sub-Seasonal Predictability of the Northeast China Cold Vortex in BCC and ECMWF S2S Model Forecasts for 2006–2021

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Journal of Meteorological Research 2024年第3期38卷 453-468页

作者： Yiqiu YU Jie WU Yihe fang Chunyu zhao Zongjian ke Yitong LIN Liaoning Provincial Climate Centre Liaoning Provincial Meteorological Administration key Opening Laboratory for Northeast China Cold Vortex Research China Meteorological Administration Panjin National Climate Observatory China Meteorological Administration key Laboratory for Climate Prediction Studies National Climate Centre China Meteorological Administration Jilin Provincial Climate Centre Jilin Provincial Meteorological Administration

As an important atmospheric circulation system in the mid–high latitudes of East Asia, the Northeast China cold vortex(NCCV) substantially influences weather and climate in this region. So far, systematic assessment on the performance of numerical prediction of the NCCVs has not been carried out. Based on the Beijing Climate Centre(BCC) and the ECMWF model hindcast and forecast data that participated in the Sub-seasonal to Seasonal(S2S) Prediction Project, this study systematically examines the performance of both models in simulating and forecasting the NCCVs at the sub-seasonal timescale. The results demonstrate that the two models can effectively capture the seasonal variations in the intensity, active days, and spatial distribution of NCCVs; however, the duration of NCCVs is shorter and the intensity is weaker in the models than in the observations. Diagnostic analysis shows that the differences in the intensity and location of the East Asian subtropical westerly jet and the wave train pattern from North Atlantic to East Asia may be responsible for the deficient simulation of NCCV events in the S2S models. Nonetheless, in the deterministic forecasts, BCC and ECMWF provide skillful prediction on the anomalous numbers of NCCV days and intensity at a lead time of 4–5(5–6) pentads, and the skill limit of the ensemble mean is 1–2 pentads longer than that of individual members. In the probabilistic forecasts of daily NCCV activities, BCC and ECMWF exhibit a forecasting skill of approximately 7 and 11 days, respectively; both models show seasonal dependency in the simulation performance and forecast skills of NCCV events, with better performance in winter than in summer.The results from this study provide helpful references for further improvement of the S2S prediction of NCCVs.

关键词： Northeast China cold vortex (NCCV) predictability sub-seasonal to seasonal (S2S) prediction deterministic forecast probabilistic forecast

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Interpretation of the Standards of Basic Dataset of Chronic Diseases Behavior Risk Factor Surveillance in Adults

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Biomedical and Environmental Sciences 2024年第5期37卷 551-556页

作者： zhao Yan fang ZHANG Mei WEI Wen Qiang SUN ke Xin LI Xin Hua WANG Li Min National Center for Chronic and Noncommunicable Disease Control and Prevention(NCNCD) Chinese Center for Disease Control and PreventionBeijing 100050China Cancer Hospital Chinese Academy of Medical SciencesBeijing 100021China Chinese Center for Disease Control and Prevention Beijing 102206China People's Medical Publishing House Beijing 100021China

BACKGROUND China’s Behavioral Risk Factor Surveillance System(BRFSS)originated from the World Bankfunded HealthⅦLoan Project in the 1990s,which conducted behavioral risk factor surveillance in seven cities and one province^([1]).Drawing on the World Health Organization’s(WHO)STEPwise approach to surveillance(STEPs)and the U.S.Behavioral Risk Factor Surveillance System(BRFSS)^([2,3]).

关键词： funded Basic originated

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Clinical observation of extraction-site incisional hernia after laparoscopic colorectal surgery

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 710-716页

作者： Bao-Hang Fan ke-Li Zhong Li-Jin Zhu zhao Chen fang Li Wen-Fei Wu Second Clinical Medical College of Jinan University Jinan UniversityShenzhen 518020Guangdong ProvinceChina Department of Gastrointestinal Surgery Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina Department of Radiation Oncology Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina

BACKGROUND Laparoscopic colorectal cancer surgery increases the risk of incisional hernia(IH)at the tumor extraction site.AIM To investigate the incidence of IH at extraction sites following laparoscopic colo-rectal cancer surgery and identify the risk factors for IH incidence.METHODS This study retrospectively analyzed the data of 1614 patients who underwent la-paroscopic radical colorectal cancer surgery with tumor extraction through the abdominal wall at our center between January 2017 and December 2022.Diffe-rences in the incidence of postoperative IH at different extraction sites and the risk factors for IH incidence were investigated.RESULTS Among the 1614 patients who underwent laparoscopic radical colorectal cancer surgery,303(18.8%),923(57.2%),171(10.6%),and 217(13.4%)tumors were ex-tracted through supraumbilical midline,infraumbilical midline,umbilical,and off-midline incisions.Of these,52 patients developed IH in the abdominal wall,with an incidence of 3.2%.The incidence of postoperative IH was significantly higher in the off-midline incision group(8.8%)than in the middle incision groups[the supraumbilical midline(2.6%),infraumbilical midline(2.2%),and umbilical incision(2.9%)groups](χ^(2)=24.985;P<0.05).Univariate analysis showed that IH occurrence was associated with age,obesity,sex,chronic cough,incision infection,and combined diabetes,anemia,and hypopro-teinemia(P<0.05).Similarly,multivariate analysis showed that off-midline incision,age,sex(female),obesity,incision infection,combined chronic cough,and hypoproteinemia were independent risk factors for IH at the site of laparoscopic colorectal cancer surgery(P<0.05).CONCLUSION The incidence of postoperative IH differs between extraction sites for laparoscopic colorectal cancer surgery.The infraumbilical midline incision is associated with a lower hernia rate and is thus a suitable tumor extraction site.

关键词： Incisional hernia Laparoscopy Colorectal cancer Incision infection

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Peculiarity of transcriptional and H3K27me3 dynamics during peach bud dormancy

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Horticultural Plant Journal 2024年第1期10卷 38-50页

作者： Yalin zhao Yong Li ke Cao Weichao fang Changwen Chen Xinwei Wang Jinlong Wu Wenwu Guo Lirong Wang The key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Fruit Tree Breeding Technology) Ministry of AgricultureZhengzhou Fruit Research InstituteChinese Academy of Agricultural SciencesZhengzhouHenan 450009China Western Research Institute Chinese Academy of Agricultural SciencesChangjiXinjiang 831100China College of Horticulture and Forestry Science Huazhong Agricultural UniversityWuhanHubei 430070China

Bud dormancy facilitates the survival of meristems under harsh environmental conditions.To elucidate how molecular responses to chilling accumulation controlling dormancy in peach buds,chromatin immunoprecipitation sequencing to identify the H3K27me3 modifications and RNA sequencing of two peach cultivars with pronounced differences in chilling requirement were carried out,the results showed that genes associated with abscisic acid and gibberellic acid signal pathways play key roles in dormancy regulation.The results demonstrated that peach flower bud differentiation occurred continuously in both cultivars during chilling accumulation,which was correlated with the transcript abundance of key genes involved in phytohormone metabolism and flower bud development under adverse conditions.The more increased strength in high chillingrequirement cultivar along with the chilling accumulation at the genome-wide level.The function of the dormancy-associated MADS-box gene PpDAM6 was identified,which is involved in leaf bud break in peach and flower development in transgenic Nicotiana tabacum(NC89).In addition,PpDAM6 was positively regulated by PpCBF,and the genes of putative dormancy-related and associated with metabolic pathways were proposed.Taken together,these results constituted a theoretical basis for elucidating the regulation of peach bud dormancy transition.

关键词： Peach bud Dormancy RNA-seq H3K27me3 Chilling requirement

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