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An Innovative Coupled Common-Node Discrete Element Method-Smoothed Particle Hydrodynamics Model Developed with LS-DYNA and Its Applications

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China Ocean Engineering 2024年第3期38卷 467-482页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue LUO Jia-xin liu ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEM-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA *** DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure *** simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are *** interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also *** results are compared with available data to verify the proposed coupling ***,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEM-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics

Numerical Simulation of Sea Ice and Structure Interaction Using Common Node DEM-SPH Model

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China Ocean Engineering 2023年第6期37卷 897-911页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue LI Hong-bin JIANG Yin liu ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this work,a novel fluid-structure coupling method called the common node discrete element-smoothed particle hydrodynamics(DS-SPH)method is *** framework combines the principles of the common node discrete element method(DEM)and smoothed particle hydrodynamics(SPH)to construct DEM-SPH particles situated on the same *** doing so,the DEM particles can interact with the SPH particles within their support domain,enabling fluid-structure interaction(FSI).To determine the DEM microscopic parameters required for this method,uniaxial compression and three-point bending tests are conducted on sea *** verify the proposed model,we select the interaction between sea ice and structures as a case *** simulation,the model's capability of accurately depicting sea ice deformation and fracture has been *** results indicate that the inclusion of SPH particles with fluid properties in the DEM model has minimal impact on the main mechanical parameters of sea ***,it helps prevent the occurrence of particle splashing during cement ***,it is observed that the size of DEM particles and the friction between DEM particles and the structure significantly influence the macroscopic mechanical behavior of the common-node DEM-SPH ***,we compare the fracture behavior of sea ice and the ice forces acting on structures obtained from the current model with on-site measured *** agreement between the two sets of data is excellent,further validating the effectiveness of the proposed model in practical applications.

关键词： common node DEM-SPH uniaxial compression three-point bending structure-ice interaction

Spatial Variability of Soil Organic Carbon Under Maize Monoculture in the Song-Nen Plain, Northeast China

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Pedosphere 2010年第1期20卷 80-89页

作者： WANG Zong-Ming , ZHANG Bai, SONG Kai-Shan, liu Dian-wei and ren Chun-Ying Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012 (China) Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 (China)

Soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils, Cambisol, Arenosol, Phaeozem, and Chernozem, were collected at 451 locations in Nongan County under maize monoculture in the Song-Nen Plain, Northeast China. The spatial characteristics of soil organic carbon were studied, using geographic information systems (GIS) and geostatistics. Effects of other soil physical and chemical properties, elevation, slope, and soil type on SOC were explored. SOC concentrations followed a normal distribution, with an arithmetic mean of 14.91 g kg-1 . The experimental variogram of SOC was fitted with a spherical model. There were significant correlations between soil organic carbon and bulk density (r =-0.374**), pH (r = 0.549**), total nitrogen (r = 0.781**), extractable phosphorus (r =-0.109*), exchangeable potassium (r = 0.565**), and cation exchange capacity (r = 0.313**). Generally, lower SOC concentrations were significantly associated with high elevation (r =-0.429**). Soil organic carbon was significantly negatively correlated with slope gradient (r =-0.195**). Samples of the Cambisol statistically had the highest SOC concentrations, and samples of the Arenosol had the lowest SOC value.

关键词： geostatistics slope soil bulk density spatial distribution

Epigenetics of hepatocellular carcinoma： a new horizon

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Chinese Medical Journal 2012年第13期125卷 2349-2360页

作者： liu wei-ren SHI Ying-hong PENG Yuan-fei FAN Jia Department of Liver Surgery Liver Cancer InstituteZhongshan HospitalFudan UniversityKey Laboratory of Carcinogenesis and Cancer Invasion of Ministry of EducationShanghai 200032China Institute of Biomedical Sciences Fudan UniversityShanghai 200032China

Epigenetic changes refer to stable alterations in gene expression with no underlying modifications in the genetic sequence itself. It has become clear that not only gene variations but also epigenetic modifications may contribute to varied diseases, including cancer. This review will provide an overview of how epigenetic factors, including genomic DNA methylation, histone modifications, and miRNA regulation, contribute to hepatocellular carcinoma （HCC） dissemination, invasion, and metastasis. Additionally, the reversal of dysregulated epigenetic changes has emerged as a potential strategy for the treatment of HCC, and we will summarize the latest epigenetic therapies for HCC.

关键词： hepatocellular carcinoma epigenetic DNA methylation miRNA

Commentary on -＂Comparison of the efficacy and safety of once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction＂

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Asian Journal of Andrology 2015年第5期17卷 854-854页

作者： De-Hong Cao Liang-ren liu Qiang wei Department of Urology West China Hospital Sichuan University ChengduSichuan Province China

Dear Editor, We read with interest of the article written by Park et al. They performed a randomized controlled trial to compare efficacy and safety between 50 mg once-daily and 200 mg on-demand dosing use of udenafil for the treatment of type 2 diabetic patients with erectile dysfunction （ED）. Their findings indicated that the most common drug-related adverse events （AEs） were flushing （8,9% vs 2,5%） and headache （3.8% vs 1.3%） between the on-demand group and the daily-dosed group. Although the authors believed that the udenafil was well-tolerated in both groups, unfortunately, they failed report the total incidence of AEs to assess the safety of the two groups.

关键词： daily-dosed compare well-tolerated

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乌鲁木齐铁路枢纽总图规划

铁道运输与经济 2014年第2期36卷 4-10页

作者：刘卫仁新疆铁道勘察设计院有限公司线路运输分处新疆乌鲁木齐830011

在分析乌鲁木齐铁路枢纽概况的基础上,为适应"一轴三翼,双核多心、三带三楔、八大分区"的空间结构和中长期铁路网规划的要求,对乌鲁木齐铁路枢纽总图规划进行调整和优化,从客运量和货运量2个方面对枢纽客货运量进行预测,结合客运系统、... 详细信息

在分析乌鲁木齐铁路枢纽概况的基础上,为适应"一轴三翼,双核多心、三带三楔、八大分区"的空间结构和中长期铁路网规划的要求,对乌鲁木齐铁路枢纽总图规划进行调整和优化,从客运量和货运量2个方面对枢纽客货运量进行预测,结合客运系统、货运系统、机务与车辆设备及解编系统等多方面规划提出乌鲁木齐铁路枢纽规划方案。

关键词：乌鲁木齐铁路枢纽规划客运系统货运系统

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu wei Zhongmin liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. Fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. Furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

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惯性导航系统水平阻尼网络的自适应控制

天津大学学报（自然科学与工程技术版） 2005年第2期38卷 146-149页

作者：刘为任庄良杰天津大学机械工程学院天津300072 天津航海仪器研究所天津300131

当海况变化较大时,惯性导航系统(INS)的误差振荡幅度较大.为了减小系统误差的振荡幅度,提出了一种新的设计思想,采用自适应控制方法,根据实际的海况变化情况,实时校正阻尼参数,使由舰船的机动性造成的系统误差最小. 结果表明,与传统方... 详细信息

当海况变化较大时,惯性导航系统(INS)的误差振荡幅度较大.为了减小系统误差的振荡幅度,提出了一种新的设计思想,采用自适应控制方法,根据实际的海况变化情况,实时校正阻尼参数,使由舰船的机动性造成的系统误差最小. 结果表明,与传统方法相比,水平误差角振荡幅度减小了约 5000,速度误差振荡幅度减小了约 3000,经度、纬度和航向误差振荡幅度也有明显改善;水平阻尼网络的自适应控制有效地改善了INS的动态性能.

关键词：惯性导航系统外水平阻尼自适应控制

惯性导航系统水平阻尼网络的适应式混合智能控制

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哈尔滨工业大学学报 2005年第11期37卷 1586-1588页

作者：刘为任庄良杰天津大学机械工程学院天津300072

目前,船用惯性导航系统(INS)主要工作在外水平阻尼状态和无阻尼状态,当海况变化较大时,系统就会在阻尼状态和无阻尼状态之间频繁转换,使系统一直处于调整状态,影响了系统的动态精度.为了改善这种状况,提出一种新的设计思想,采用适应式... 详细信息

目前,船用惯性导航系统(INS)主要工作在外水平阻尼状态和无阻尼状态,当海况变化较大时,系统就会在阻尼状态和无阻尼状态之间频繁转换,使系统一直处于调整状态,影响了系统的动态精度.为了改善这种状况,提出一种新的设计思想,采用适应式混合智能控制,根据实际海况变化情况,实时校正阻尼系数,使由舰船的机动性造成的系统误差最小.理论分析和仿真结果表明,该方案能有效地改善INS的动态性能.

关键词： INS 外水平阻尼适应式混合智能控制