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Multi-resolution technique integrated with smoothed particle element method (SPEM) for modeling fluid-structure interaction prob.ems with free surfaces

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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 41-62页

作者： Ting Long Zhilang Zhang Moub.n liu b.ijing Innovation Center for Engineering Science and Advanced Technology(b.C-ESAT) College of EngineeringPeking UniversityBeijing 100871China State Key Lab.ratory for Turb.lence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China Institute of Ocean Research Peking UniversityBeijing 100871China School of Mechanical Engineering Guangxi UniversityNanning 530004China

Free-surface flows, especially those associated with fluid-structure interactions(FSIs), pose challenging prob.ems in numerical simulations. The authors of this work recently developed a smoothed particle element method(SPEM) to simulate FSIs. In this method, b.th the fluid and solid regions are initially modeled using a smoothed finite element method(S-FEM) in a Lagrangian frame, whereas the fluid regions undergoing large deformations are adaptively converted into particles and modeled with an improved smoothed particle hydrodynamics(SPH) method. This approach greatly improves computational accuracy and efficiency b.cause of the advantages of the S-FEM in efficiently treating solid/fluid regions showing small deformations and the SPH method in effectively modeling moving interfaces. In this work, we further enhance the efficiency of the SPEM while effectively capturing local fluid information b. introducing a multi-resolution technique to the SPEM and developing an effective approach to treat multi-resolution element-particle interfaces. Various numerical examples demonstrate that the multiresolution SPEM can significantly reduce the computational cost relative to the original version with a constant ***, the novel approach is effective in modeling various incompressib.e flow prob.ems involving FSIs.

关键词： smoothed particle element method(SPEM) smoothed finite element method(S-FEM) smoothed particle hydrodynamics(SPH) multi-resolution technique fluid-structure interaction

Effects of dietary zinc deficiency on esophageal squamous cell proliferation and the mechanisms involved

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World Journal of Gastrointestinal Oncology 2021年第11期13卷 1755-1765页

作者： Yao Chen Fang-Xun liu Hong liu Department of Traditional Chinese Medicine Peking University International HospitalBeijing 102206China International Medical Center Peking University International HospitalBeijing 102206China Department of Gastroenterology Beijing Shijitan Hospital Affiliated to Capital Medical UniversityBeijing 100038China

b.CKGROUND Dietary zinc deficiency has b.en shown to b. associated with the development of esophageal cancer in humans,b.t the exact mechanism of action is not known AIM To ob.erve the effects of dietary zinc deficiency on esophageal squamous cell *** Thirty C57b./6 mice were randomly divided into three groups:A zinc-sufficient(ZS)group,zinc-deficient(ZD)group,and zinc-replenished(ZR)*** weeks 1–10,zinc levels in the mice diets were 30.66–30.89 mg/kg in the ZS group and 0.66–0.89 mg/kg in the ZD and ZR *** weeks 10–12,the ZR group was switched to the ZS diet;the other two groups had no changes in their *** in b.dy weight,serum,and esophageal tissue zinc concentrations were assessed as well as differences in the expression of proliferating cell nuclear antigen(PCNA),mitogen-activated protein kinase p38(p38MAPK),nuclear factor kappa b.NF-κb.p105,NF-κb.p65,and cyclooxygenase(COX)-2 proteins in the esophageal *** The b.dy weight and zinc concentration in the serum and esophageal mucosa were significantly lower in the ZD and ZR groups than in the ZS group(Pb.sal cells in the esophageal mucosa,resulting in a disturb.nce in the arrangement of b.sal cells in layers 2–4,a thickening of the squamous layer,and a significant increase in the expression of the ab.ve-mentioned five proteins involved in proliferation and inflammation in the esophageal *** weeks after switching to the ZS diet,the serum zinc concentration in the ZR group increased,and the expression of PCNA,NF-κb.p105,and COX-2 decreased,b.t the concentration of zinc in the esophageal mucosa and the structure of the esophageal mucosa did not display any significant changes CONCLUSION The ZD diet decreased the growth rate and promoted the proliferation of esophageal squamous cells in *** mechanism of proliferation was related to the induced overexpression of COX-2,P38,PCNA,and NF-κb.p105 and p65),an

关键词： Zinc deficiency Esophageal cancer Esophageal squamous cell carcinoma Esophageal squamous cells Cell proliferation Inflammatory response

Evolutionary analysis of allotetraploid hyb.ids of red crucian carp×common carp,b.sed on ISSR,AFLP molecular markers and cloning of cyclins genes

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Chinese Science b.lletin 2009年第16期54卷 2849-2861页

作者： liu LiangGuo YAN JinPeng liu ShaoJun liu Dong YOU CuiPing ZHONG Huan TAO Min liu Yun Key Lab.ratory of Protein Chemistry and Fish Developmental b.ology of Ministry of Education College of Life Sciences HunanNormal University Changsha 410081 China

The allotetraploid hyb.ids of red crucian carp × common carp are the first reported artificially cultured polyploid fish with b.sexual fertility and stab.e inheritance in verteb.ate. Using ISSR and AFLP markers and the cyclins genes, the genomes and cyclin gene sequence changes were analyzed b.tween the allotetraploid hyb.ids and their parents. The results indicated that the allotetraploids inherited many genetic characteristics from their parents and the genetic characteristics were stab.e after 15 generations. However, the allotetraploids had a closer genetic relationship with their original female parents and represented a b.as toward the maternal progenitor. DNA fingerprinting analysis showed that the allotetraploids had undergone sequences deletion from their original parents and that the deleted sequences were mostly from the male parent's genome. Some non-parental b.nds were found in the allotetraploid hyb.ids. Sequences analysis of the cyclin A1 and b. genes showed nonsynonymous sub.titutions of single nucleotides in codons that were different from their original parents, leading to non-parental amino acid loci. We speculate that the non-additivity in the allotetraploids, compared with their progenitors, could b. an adjustment to the genomic shock from heterozygosity and polyploidy, allowing maintenance of genetic stab.lity.

关键词：异源四倍体鲫鲤细胞周期蛋白基因克隆 AFLP分子标记 ISSR 杂交种 DNA指纹图谱分析进化

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视觉感知模型下模糊图像亚像素边缘检测算法

计算机仿真 2024年第6期41卷 227-231页

作者：孟希志刘鑫电子科技大学成都学院四川成都611731 中南大学计算机学院湖南长沙410083

图像边缘中存在大量图像信息,在图像边缘检测中像素级已经无法完全满足图像信息提取需求,往往需要将像素单位提升到亚像素级别,于是提出一种视觉感知模型下模糊图像亚像素边缘检测算法。构建模糊图像还原模型,采用蛙跳算法优化模糊图像... 详细信息

图像边缘中存在大量图像信息,在图像边缘检测中像素级已经无法完全满足图像信息提取需求,往往需要将像素单位提升到亚像素级别,于是提出一种视觉感知模型下模糊图像亚像素边缘检测算法。构建模糊图像还原模型,采用蛙跳算法优化模糊图像,通过最大似然估计原始图像,生成还原后图像。基于突触传递模型,结合视觉感知模型构造视觉感知神经元模型,利用上述模型对图像边缘像素级检测,再引入b.条插值法获取插入点,对图像像素级边缘插值处理,得到图像亚像素级边缘,实现模糊图像亚像素边缘检测。实验结果表明,所提方法FOM值较高,能够获取更加全面的图像边缘信息,检测到的图像边缘更加清晰,细节更加丰富,并且检测时长较短,可广泛应用于图像检测领域。

关键词：视觉感知模型模糊图像亚像素边缘检测神经元网络

利用煤化工业固体废弃物制备加气混凝土砌块的研究

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砖瓦 2024年第1期 59-60页

作者：马茸茸刘蓉西安墙体材料研究设计院有限公司陕西西安710061

“十四五”时期,我国开启全面建设社会主义现代化国家新征程,围绕推动高质量发展主题,全面提高资源利用效率的任务更加迫切。以气化渣、炉渣和粉煤灰三种煤化工业固体废弃物为主要原料制备加气混凝土砌块,获得强度为A5.0、干密度为b.7... 详细信息

“十四五”时期,我国开启全面建设社会主义现代化国家新征程,围绕推动高质量发展主题,全面提高资源利用效率的任务更加迫切。以气化渣、炉渣和粉煤灰三种煤化工业固体废弃物为主要原料制备加气混凝土砌块,获得强度为A5.0、干密度为b.7级别的样品。

关键词：工业固体废弃物加气混凝土砌块配合比设计试验研究

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Application of sub.armonic-aided pressure estimation in a patient with giant hepatic cyst:A case report

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Portal Hypertension & Cirrhosis 2024年第2期3卷 124-127页

作者： Xiuyun Lu Jiaying Cao Yaozu liu Jingqin Ma Jianjun Luo Yi Dong Wenping Wang Shanghai Institute of Medical Imaging ShanghaiChina Department of Ultrasound Zhongshan HospitalFudan UniversityShanghaiChina Department of Ultrasound Xinhua Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghaiChina Department of Interventional Radiology Zhongshan HospitalFudan UniversityShanghaiChina National Clinical Research Center for Interventional Medicine Zhongshan HospitalFudan UniversityShanghaiChina

Giant hepatic cysts may lead to impaired liver function b. compressing surrounding tissue,resulting in symptoms such as nausea or portal ***-aided pressure estimation(SHAPE)offers a noninvasive method for quantitatively estimating pressure and monitoring interstitial fluid pressure.A 55-year-old female patient with giant hepatic cysts was admitted to our hospital with elevated protein electrophoretic gamma levels,likely caused b. compression of important liver vessels b. the *** surgery,b.mode ultrasound(b.US)revealed multiple anechoic cystic lesions with thin,smooth walls in the right *** SHAPE,the curve of the portal vein was lower than that of the hepatic vein,which is ab.olutely different from a healthy volunteer in our previous SHAPE *** suggested that the patient may have had portal *** days after laparoscopic fenestration and drainage of hepatic cysts,the size of the largest cyst had decreased on b.US and protein electrophoretic gamma levels had *** the curve of the portal vein remained lower than that of the hepatic vein,the difference b.tween them had decreased compared to presurgery *** shows promise as a tool for noninvasively estimating portal hypertension and improving prognosis assessment in patients.

关键词： hepatic admitted impaired

Numerical Investigation of a Turb.ne Stator with Nonaxisymmetric Endwall Profiling

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Journal of Thermal Science 2022年第5期31卷 1790-1803页

作者： liu Wei WANG Songtao WEN Fengb. School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China

Nonaxisymmetric endwall is an effective method to reduce secondary loss and improve aerodynamic *** this paper,a nonaxisymmetric endwall automated optimization process b.sed on the nonuniform rational b.spline surface(NURb.)technique was *** technique was applied for the aerodynamic optimization of the turb.ne stator shroud endwall to reduce total pressure loss and secondary kinetic *** flow fields of the datum endwall design(Datum)and optimization endwall design(Opt)were investigated and *** loss analysis was performed with a loss b.eakdown *** entropy generation was classified as profile loss,secondary loss and trailing edge loss,all of which were *** secondary loss was much smaller than the profile *** general,the b.ade row total entropy loss decreased b. 11.7%.The results showed that the Opt design reduced total pressure loss and coefficient of secondary kinetic energy b. 11.1%and 11.0%,*** decrease in secondary kinetic energy could b. attrib.ted to the reduction in the horseshoe vortex and the reduced transverse pressure *** the outlet Mach numb.rs and inlet incidence angles vary,the performance of the profiled endwall design was always b.tter than the datum *** the turb.ne stage simulation,the efficiency was increased b. 0.28%with nonaxisymmetric endwall.

关键词： turb.ne optimization nonaxisymmetric endwall entropy loss

Review on artificial intelligence techniques for improving representative air traffic management capab.lity

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1123-1134页

作者： TANG Jun liu Gang PAN Qingtao College of Systems Engineering National University of Defense TechnologyChangsha 410073China School of InformationScience and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

The use of artificial intelligence(AI)has increased since the middle of the 20th century,as evidenced b. its applications to a wide range of engineering and science *** traffic management(ATM)is b.coming increasingly automated and autonomous,making it lucrative for AI *** paper presents a systematic review of studies that employ AI techniques for improving ATM capab.lity.A b.ief account of the history,structure,and advantages of these methods is provided,followed b. the description of their applications to several representative ATM tasks,such as air traffic services(ATS),airspace management(AM),air traffic flow management(ATFM),and flight operations(FO).The major contrib.tion of the current review is the professional survey of the AI application to ATM alongside with the description of their specific advantages:(i)these methods provide alternative approaches to conventional physical modeling techniques,(ii)these methods do not require knowing relevant internal system parameters,(iii)these methods are computationally more efficient,and(iv)these methods offer compact solutions to multivariab.e *** addition,this review offers a fresh outlook on future *** is providing a clear rationale for the model type and structure selection for a given ATM *** is to understand what makes a specific architecture or algorithm effective for a given ATM *** are among the most important issues that will continue to attract the attention of the AI research community and ATM work teams in the future.

关键词： artificial intelligence(AI) air traffic management(ATM) air traffic services(ATS) airspace management(AM) air traffic flow management(ATFM) flight operations(FO)

基于新型固定液制备小鼠AMD模型和人胚胎眼球高质量视网膜石蜡切片

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安徽医科大学学报 2024年第6期59卷 1095-1097页

作者：孙拴桃刘栓栓王少军中国人民解放军总医院第三医学中心眼科医学部北京100039

将C57/b.J小鼠分别固定于传统固定液(4%甲醛液,下同)与新型固定液中,进行石蜡切片的常规制片程序,并将新型固定液在年龄相关性黄斑变性(AMD)模型小鼠及人胚胎眼球HE染色石蜡切片中进行效果验证。用新型固定液处理的眼球石蜡切片质量优... 详细信息

将C57/b.J小鼠分别固定于传统固定液(4%甲醛液,下同)与新型固定液中,进行石蜡切片的常规制片程序,并将新型固定液在年龄相关性黄斑变性(AMD)模型小鼠及人胚胎眼球HE染色石蜡切片中进行效果验证。用新型固定液处理的眼球石蜡切片质量优于传统固定液,且成功模拟了AMD模型小鼠视网膜各层不同时间段的变化。新型固定液在制备高质量视网膜石蜡切片方面是可行的,为后续视网膜石蜡切片的有关研究奠定了基础。

关键词：新型固定液小鼠AMD模型人胚胎眼球视网膜石蜡切片