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Research on the generation method of seawater sound velocity model based on Perlin noise

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Acta Oceanologica Sinica 2024年第1期43卷 99-111页

作者： Zhimiao Chang fuxing Han Zhangqing Sun Zhenghui Gao Xueqiu Wang College of Geoexploration Science and Technology Jilin UniversityChangchun 130026China

In the processing of conventional marine seismic data,seawater is often assumed to have a constant velocity ***,due to static pressure,temperature difference and other factors,random disturbances may often frequently in seawater *** impact of such disturbances on data processing results is a topic of theoretical *** seawater sound velocity is a difficult physical quantity to measure,there is a need for a method that can generate models conforming to seawater *** article will combine the Munk model and Perlin noise to propose a two-dimensional dynamic seawater sound velocity model generation method,a method that can generate a dynamic,continuous,random seawater sound velocity model with some regularity at large ***,the paper discusses the influence of the inhomogeneity characteristics of seawater on wave field propagation and *** results show that the seawater sound velocity model with random disturbance will have a significant influence on the wave field simulation and imaging results.

关键词： Munk model Perlin noise seawater inhomogeneity

Experimental Study on Rotation Resistance Coefficient of Motor Bogie for Type A Vehicle

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Journal of Harbin Institute of Technology(New Series) 2019年第2期26卷 90-96页

作者： fuxing tan Hongtao Liu Shihui Liu Zhenchuan Zhang Peng Zhang Railway Vehicles Laboratory CRRC Changchun Railway Vehicles Co.Ltd.

Rotation resistance coefficient is an important operating parameter for vehicle bogies, which influences the dynamic behavior of vehicles directly. A research on the rotation resistance coefficient of type A vehicle motor bogies was conducted by means of theoretical calculation, dynamic simulation, test certification, and so on. Result of the simulation analysis shows that the rotation resistance coefficient relates to air springs stiffness and negotiated curve radii, and it varies proportionally with the change of air springs horizontal stiffness. The greater the rotation angle is, the greater the factor becomes. The certifications made under the operating conditions(e.g., different air spring status, different rotation speeds) indicate that the rotation resistance coefficient increases with the increase of the rotation speed. The anti-yaw dampers can contribute to the rotation resistance torque acted on bogie, and the greater the rotation speeds are, the greater the torque generated by the anti-yaw dampers is. The results suggest that the theoretical analysis and dynamics simulation are in accordance with the results from the bogie bench tests, which meet the requirements in EN14363 and the indicators in vehicles safe operation.

关键词： type A vehicle motor bogie rotation angle rotation resistance coefficient rotation speed

Evolution model and failure mechanisms of rainfall-induced cracked red clay slopes:insights from Xinshao County,China

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Journal of Mountain Science 2024年第3期21卷 867-881页

作者： JIAO Weizhi ZHANG Ming LI Peng XIE Junjin PANG Haisong LIU fuxing YANG Long Faculty of Engineering China University of GeosciencesWuhan 430074China

Red clay landslides are widely distributed worldwide,resulting in severe loss of life and *** rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary process of red clay slopes and their connection to failure mechanisms is still poorly understood.A comprehensive approach integrating field investigation,laboratory tests,and numerical simulations was conducted to study the 168 red clay landslides in Xinshao County,*** results show that red clay is prone to forming cracks at high moisture content due to its low swelling and high shrinkage *** failure mode of red clay slopes can be summarized in three stages:crack generation,slope excavation,and slope ***,the retrospective analysis and numerical simulations of the typical landslide in Guanchong indicated that intense rainfall primarily impacts the shallow layer of soil within approximately 0.5 m on the intact ***,cracks change the pattern of rainfall infiltration in the *** infiltrates rapidly through the preferential channels induced by the cracks rather than uniformly and slowly from the slope *** results in a significant increase in both the depth of infiltration and the saturated zone area of the cracked slope,reaching 3.8 m and 36.2 m^(2),***,the factor of safety of the slope decreases by 13.4%compared to the intact slope,ultimately triggering *** study can provide valuable insights into understanding the failure mechanisms of red clay slopes in China and other regions with similar geological settings.

关键词： Red clay slopes Cracks Preferential flow Failure mechanism

High dose of tranexamic acid infusion in primary total knee arthroplasty:A randomized multicenter clinical trail

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Chinese Medical Journal 2024年第3期137卷 359-361页

作者： Jinwei Xie Qiang Huang Zeyu Huang Fei Wang Jun Liu Hua Tian Wei Huang fuxing Pei Department of Orthopaedic Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of Orthopaedic Surgery The Third Hospital of Hebei Medical UniversityShijiazhuangHebei 050051China Department of Orthopaedic Surgery Tianjin HospitalTianjin 300211China Department of Orthopaedic Surgery Peking University Third HospitalHaidian DistrictBeijing 100191China Department of Orthopaedic Surgery The First Affiliated Hospital of Chongqing Medical UniversityYuzhong DistrictChongqing 400016China

To the Editor:Significant hyperfibrinolysis is always accompanied by surgical trauma and tourniquet use in total knee arthroplasty(TKA),leading to considerable hidden blood loss,inflammation,and pain,thereby impeding the recovery *** recovery after surgery(ERAS)has promoted the development of patient blood management in recent *** numerous methods of blood conservation,including tranexamic acid(TXA),a lysine analog competitive inhibitor of plasmin and plasminogen,have been studied.^([1–3])However,some issues remain controversial,such as the optimal TXA regimen in *** the other hand,the use of TXA in arthroplasty is considered off-label,although the current guideline or consensus suggests its routine use in arthroplasty.

关键词： arthroplasty infusion routine

“外师造化”:一个中国古代山水画尚未解决的问题

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文艺研究 2024年第5期 5-19页

作者：薛富兴南开大学哲学院

虽然山水画自元代即为画科之尊,具有标识古人精神世界之个性与高度的崇高地位,但其仍存在重要缺陷。“外师造化”这一基础性问题尚未得到根本解决,致使山水画未能真实、系统地呈现中国古代自然地理景观的突出个性与丰富性,未能深入揭示... 详细信息

虽然山水画自元代即为画科之尊,具有标识古人精神世界之个性与高度的崇高地位,但其仍存在重要缺陷。“外师造化”这一基础性问题尚未得到根本解决,致使山水画未能真实、系统地呈现中国古代自然地理景观的突出个性与丰富性,未能深入揭示山川、树石对象的内在特征。山水意象程式化严重,山水景观陈陈相因,未能成功建立起一套关于如何“外师造化”的语言及技法系统。其内在原因在于,中国古代山水画家普遍在认识自然方面未能做好深入、细致地探究内在之真的格物致知功课,也未能在哲学上培育出独立地对待和呈现自然的根本立场。在当代语境下,如何开拓出真正以自然为本的新型山水画,乃中国山水画的时代新课题。

关键词：外师造化画科以自然为本山水景观山水画山水意象尚未解决的问题格物致知

Efficacy and safety of first-line treatment for metastatic triple-negative breast cancer:A network meta-analysis

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Cancer Pathogenesis and Therapy 2024年第2期2卷 81-90页

作者： Mingqiang Shi Zhoujuan Li Guoshuang Shen Tianzhuo Wang Jinming Li Miaozhou Wang Zhen Liu fuxing Zhao Dengfeng Ren Jiuda Zhao Breast Disease Diagnosis and Treatment Center of Affiliated Hospital of Qinghai University&Affiliated Cancer Hospital of Qinghai UniversityXiningQinghai 810000China

Background:Metastatic triple-negative breast cancer(mTNBC)is an aggressive histological subtype with poor *** first-line treatments are currently available for *** study conducted a network meta-analysis to compare these first-line regimens and to determine the regimen with the best ***:A systematic search of PubMed,EMBASE,the Cochrane Central Register of Controlled Bases,and mi-nutes of major conferences was ***-free survival(PFS),overall survival(OS),and objective response rate(ORR)were analyzed via network meta-analysis using the R software(R Core Team,Vienna,Austria).The efficacy of the treatment regimens was compared using hazard ratios and 95%confidence ***:A total of 29 randomized controlled trials involving 4607 patients were *** ranking was based on the surface under the cumulative ranking *** meta-analysis results showed that cisplatin combined with nab-paclitaxel or paclitaxel was superior to docetaxel plus capecitabine in terms of PFS and *** programmed death-ligand 1(PD-L1)and breast cancer susceptibility gene(BRCA)mutation-positive tumors,atezolizumab/pembrolizumab combined with nab-paclitaxel and talazoparib was superior to docetaxel plus *** significant difference was observed among the treatments in ***,diarrhea,and fatigue were common serious adverse ***:Cisplatin combined with nab-paclitaxel or paclitaxel is the preferred first-line treatment for *** PD-L1 and BRCA mutation-positive tumors,atezolizumab/pembrolizumab combined with nab-paclitaxel and talazoparib is an effective treatment option,Neutropenia,diarrhea,and fatigue are frequently occurring serious adverseevents.

关键词： Metastatictriple-negativebreast cancer First-line treatment Chemotherapy Immune-checkpoint inhibitors Poly(ADP-Ribose)polymerase inhibitors AKT inhibitor Networkmeta-analysis

Horizontal-to-vertical spectral ratio inversion method based on multimodal forest optimization algorithm

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Global Geology 2024年第3期27卷 167-176页

作者： CHEN Xuanning HAN fuxing GAO Zhenghui SUN Zhangqing HAN Jiangtao College of Geo-Exploration Science and Technology Jilin UniversityChangchun 130026China

The exploration of urban underground spaces is of great significance to urban planning,geological disaster prevention,resource exploration and environmental ***,due to the existing of severe interferences,conventional seismic methods cannot adapt to the complex urban environment *** adopting the single-node data acquisition method and taking the seismic ambient noise as the signal,the microtremor horizontal-to-vertical spectral ratio(HVSR)method can effectively avoid the strong interference problems caused by the complex urban environment,which could obtain information such as S-wave velocity and thickness of underground formations by fitting the microtremor HVSR ***,HVSR curve inversion is a multi-parameter curve fitting *** conventional inversion methods can easily converge to the local minimum,which will directly affect the reliability of the inversion ***,the authors propose a HVSR inversion method based on the multimodal forest optimization algorithm,which uses the efficient clustering technique and locates the global optimum *** on synthetic data show that the inversion results of the proposed method are consistent with the forward *** the adaption and stability to the abnormal layer velocity model are *** results of the real field data are also verified by the drilling information.

关键词： microtremor HVSR method multimodal forest optimization algorithm HVSR curve inversion

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带孔网板数字化多点成形过程中拉裂缺陷的有限元分析

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机械工程学报 2008年第6期44卷 120-124页

作者：谭富星李明哲蔡中义吉林大学辊锻工艺研究所长春130025

采用动态显式有限元软件建立多点成形拉延有限元模型,对不同厚度的带孔网板和无孔板多点拉延成形进行数值模拟。利用成形极限图判断板料成形过程中是否被拉裂。模拟结果表明,在相同的成形条件下,带孔网板拉延成形时容易发生拉裂缺陷。... 详细信息

采用动态显式有限元软件建立多点成形拉延有限元模型,对不同厚度的带孔网板和无孔板多点拉延成形进行数值模拟。利用成形极限图判断板料成形过程中是否被拉裂。模拟结果表明,在相同的成形条件下,带孔网板拉延成形时容易发生拉裂缺陷。分析带孔网板成形时容易被拉裂的原因,得到无孔板和带孔网板拉延成形时拉裂临界。对在基本体和网板之间放置弹性介质和钢质垫板的成形方式进行数值模拟和试验验证,结果表明带孔网板成形效果很好,而且模拟结果和试验结果吻合良好。

关键词：多点成形带孔网板拉延成形拉裂数值模拟

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钛合金网板多点成形起皱缺陷的数值模拟

西安交通大学学报 2007年第9期41卷 1026-1030页

作者：谭富星李明哲蔡中义孙刚吉林大学无模成形技术开发中心长春130025

采用动态显式有限元软件,针对不同厚度、不同曲率半径的带孔网板和无孔板球形面的无压边多点成形过程进行了数值模拟.模拟结果表明,在相同的成形条件下,带孔网板成形球形件时不易起皱,成形效果较好.分析表明,带孔网板成形时不易起皱的... 详细信息

采用动态显式有限元软件,针对不同厚度、不同曲率半径的带孔网板和无孔板球形面的无压边多点成形过程进行了数值模拟.模拟结果表明,在相同的成形条件下,带孔网板成形球形件时不易起皱,成形效果较好.分析表明,带孔网板成形时不易起皱的原因是网孔吸收了部分金属变形,从而减小了网板起皱的趋势.通过模拟得到了带孔网板和无孔板成形球面件时不起皱成形极限与板厚的关系曲线.实验结果表明,模拟结果与实验结果吻合良好,且满足与不起皱成形极限图的对应关系.

关键词：多点成形钛合金带孔网板起皱数值模拟