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Wave action by arrays of vertical cylinders with arbitrary smooth cross-section

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Journal of Hydrodynamics 2020年第1期32卷 70-81页

作者： jia-bin liu An-xin Guo Qing-he Fang Hui Li Hui Hu Peng-fei liu Key Lab of Structures Dynamic Behavior and Conrol of the Ministry of Education Harbin Institute of Techno-logyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China Depariment of Aerospace Engineering lowa State UniversityAmeslowa 50011USA China Railway Bridge Science Research Institute LtdWuhan 430034China

This paper presents an analytical model to solve the linear wave diffraction problem by arrays of bottom-mounted cylinders with arbitrary smooth *** on the assumption of ideal fluid and potential theory,the unknown coefficients of total velocity potential can be solved by system of linear equations,which are obtained from the boundary *** accuracy of the present method is verified by comparing it with the numerical tool in terms of the wave force and wave *** cylinders with different configurations are tested,the cross-section of which is circular with cosine *** results show that the proposed method could obtain an accurate prediction of the wave action with multiple cylinder ***,the diffraction wave is investigated on arrays of bottom-mounted cylinders with different cross-section and *** near-trapping problem with effects of the multi-body interaction are also investigated.

关键词： Wave diffraction cylinder array arbitrary smooth cross-section analytical solution

Establishment of predictive models and determinants of preoperative gastric retention in endoscopic retrograde cholangiopancreatography

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2574-2582页

作者： Ying jia Hao-Jun Wu Tang Li jia-bin liu Ling Fang Zi-Ming liu Department of Thyroid Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Division of Biliary Tract Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Division of General Surgery West China Hospital-Chengdu Shangjin NanfuWest China HospitalChengdu 611730Sichuan ProvinceChina

BACKGROUND Study on influencing factors of gastric retention before endoscopic retrograde cholangiopancreatography(ERCP)background:With the wide application of ERCP,the risk of preoperative gastric retention affects the smooth progress of the *** study found that female,biliary and pancreatic malignant tumor,digestive tract obstruction and other factors are closely related to gastric retention,so the establishment of predictive model is very important to reduce the risk of *** A retrospective analysis was conducted on 190 patients admitted to our hospital for ERCP preparation between January 2020 and February *** baseline clinical data were collected using an electronic medical record *** were randomly matched in a 1:4 ratio with data from 190 patients during the same period to establish a validation group(n=38)and a modeling group(n=152).Patients in the modeling group were divided into the gastric retention group(n=52)and non-gastric retention group(n=100)based on whether gastric retention occurred *** data of patients in the validation group and identify factors influencing preoperative gastric retention in ERCP patients.A predictive model for preoperative gastric retention in ERCP patients was constructed,and calibration curves were used for *** receiver operating characteristic(ROC)curve was analyzed to evaluate the predictive value of the *** We found no statistically significant difference in general data between the validation group and modeling group(P>0.05).The comparison of age,body mass index,hypertension,and diabetes between the two groups showed no statistically significant difference(P>0.05).However,we noted statistically significant differences in gender,primary disease,jaundice,opioid use,and gastrointestinal obstruction between the two groups(P<0.05).Mul-tivariate logistic regression analysis showed that gender,primary disease,jaundice,opioid use,and gastrointestina

关键词： Cholangiopancreatography Gastric retention Influencing factors Predictive model Endoscope

Research progress on advanced rail materials for electromagnetic railgun technology

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Defence Technology（防务技术） 2021年第2期17卷 429-439页

作者： Hong-bin Xie Hui-ya Yang jian Yu Ming-yu Gao jian-dong Shou You-tong Fang jia-bin liu Hong-tao Wang School of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Center for X-mechanics Faculty of EngineeringZhejiang UniversityHangzhou310027China

Electromagnetic railgun attracts more and more attention due to its advantage in speed,cost,and *** is found that the rail should withstand huge mechanical and thermal shocks during the launching *** forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,*** service life of the rail has become a bottleneck restricting the development of electromagnetic railgun technology.A series of researches are carried out to solve rail failure,including analysing the failure mechanism and using various advanced rail *** paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and *** begin from a short background of the requirement of the rail *** a detailed investigation of rail materials is described,and the performances of those materials are ***,further development prospect of rail material is discussed.

关键词： Strength Conductivity Electromagnetic railgun Copper alloys Rai

Prediction model establishment and validation for enteral nutrition aspiration during hospitalization in patients with acute pancreatitis

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2583-2591页

作者： Ping Hou Hao-Jun Wu Tang Li jia-bin liu Quan-Qing Zhao Hong-jiang Zhao Zi-Ming liu Division II of General Surgery West China Hospital-Chengdu Shangjin NanfuWest China HospitalSichuan UniversityChengdu 611730Sichuan ProvinceChina Division of Biliary Tract Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Hepatobiliary and Pancreatic Surgery West China Hospital-Chengdu Shangjin NanfuWest China HospitalSichuan UniversityChengdu 611730Sichuan ProvinceChina Department of Thyroid Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Oncology West China Hospital-Chengdu Shangjin NanfuWest China HospitalSichuan UniversityChengdu 611730Sichuan ProvinceChina Division of Biliary Tract Surgery Department of General SurgeryWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Acute pancreatitis(AP)is a disease caused by abnormal activation of pancreatic enzymes and can lead to self-digestion of pancreatic tissues and dysfunction of other *** nutrition plays a vital role in the treatment of AP because it can meet the nutritional needs of patients,promote the recovery of intestinal function,and maintain the barrier and immune functions of the ***,the risk of aspiration during enteral nutrition is high;once aspiration occurs,it may cause serious complications,such as aspiration pneumonia,and suffocation,posing a threat to the patient’s *** study aims to establish and validate a prediction model for enteral nutrition aspiration during hospitalization in patients with *** To establish and validate a predictive model for enteral nutrition aspiration during hospitalization in patients with *** A retrospective review was conducted on 200 patients with AP admitted to Chengdu Shangjin Nanfu Hospital,West China Hospital of Sichuan University from January 2020 to February *** data were collected from the electronic medical record *** were randomly divided into a validation group(n=40)and a modeling group(n=160)in a 1:4 ratio,matched with 200 patients from the same time *** modeling group was further categorized into an aspiration group(n=25)and a non-aspiration group(n=175)based on the occurrence of enteral nutrition aspiration during *** and multivariate logistic regression analyses were performed to identify factors influencing enteral nutrition aspiration in patients with AP during hospitalization.A prediction model for enteral nutrition aspiration during hospitalization was constructed,and calibration curves were used for *** operating characteristic curve analysis was conducted to evaluate the predictive value of the *** There was no statistically significant difference in general data between the validation and mode

关键词： Acute pancreatitis Hospitalization Enteral nutrition Predictive model Aspiration

Establishment and validation of a predictive model for peripherally inserted central catheter-related thrombosis in patients with liver cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2221-2231页

作者： Xiao-Fei Chen Hao-Jun Wu Tang Li jia-bin liu Wen-Jie Zhou Qiang Guo Department of Thyroid Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina The Second Department of General Surgery Chengdu Shangjinnanfu HospitalWest China Hospital of Sichuan UniversityChengdu 611730Sichuan ProvinceChina Department of Biliary Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Chengdu Shangjinnanfu HospitalWest China Hospital of Sichuan UniversityChengdu 611730Sichuan ProvinceChina Department of Vascular Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Peripherally inserted central catheters(PICCs)are commonly used in hospitalized patients with liver cancer for the administration of chemotherapy,nutrition,and other ***,PICC-related thrombosis is a serious complication that can lead to morbidity and mortality in this patient *** risk factors have been identified for the development of PICC-related thrombosis,including cancer type,stage,comorbidities,and catheter *** these risk factors and developing a predictive model can help healthcare providers identify high-risk patients and implement preventive measures to reduce the incidence of *** To analyze the influencing factors of PICC-related thrombosis in hospitalized patients with liver cancer,construct a predictive model,and validate *** Clinical data of hospitalized patients with liver cancer admitted from January 2020 to December 2023 were ***-five cases of PICC-related thrombosis in hospitalized patients with liver cancer were collected,and 220 patients who underwent PICC placement during the same period but did not develop PICC-related thrombosis were randomly selected as controls.A total of 255 samples were collected and used as the training set,and 77 cases were collected as the validation set in a 7:3 *** patient information,case data,catheterization data,coagulation indicators,and Autar Thrombosis Risk Assessment Scale scores were *** and multivariate unconditional logistic regression analyses were performed on relevant factors,and the value of combined indicators in predicting PICC-related thrombosis in hospitalized patients with liver cancer was evaluated using receiver operating characteristic(ROC)curve *** Univariate analysis showed statistically significant differences(P<0.05)in age,sex,Karnofsky performance status score(KPS),bedridden time,activities of daily living impairment,parenteral nutrition,catheter duration,d

关键词： Liver cancer Peripherally inserted central catheters Thrombosis Model Verify

Microstructure and hardness of Cu-12% Fe composite at different drawing strains

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第2期15卷 149-156页

作者： Xiao-pei LU Da-wei YAO Yi CHEN Li-tian WANG An-ping DONG Liang MENG jia-bin liu Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China China Railway Construction Electrification Bureau Group Co. Ltd. Beijing 100036 China College of Electrical Engineering Zhejiang University Hangzhou 310027 China

Cu-12% Fe （in weight） composite was prepared by casting, pretreating, and cold drawing. The microstructure was observed and Vickers hardness was measured for the composite at various drawing strains. Cu and Fe grains could evolve into aligned filaments during the drawing process. X-ray diffraction （XRD） was used to analyze the orientation evolution during the drawing process. The axial direction of the filamentary structure has different preferred orientations from the radial directions. The strain of Fe grains linearly increases with an increase in the drawing strain up to 6.0, and deviates from the linear relation when the drawing strain is higher than 6.0. With an increase in the drawing strain, the microstructure scales of Fe filaments exponentially decrease. The density of the interface between Cu and Fe phases exponentially increases with an increase in the aspect ratio of Fe filaments. There is a similar Hall-Perch relationship between the hardness and Fe filament spacing. The refined microstructure from drawing deformation at drawing strains lower than 3.0 can induce a more significant hardening effect than that at drawing strains higher than 3.0.

关键词： Cu-12% Fe alloys Drawing Microstructure Hardness

冷拉拔Cu-2.5% Fe-0.2% Cr和Cu-6% Fe合金的显微组织与性能（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第8期16卷 622-629页

作者： Guo-huan BAO Yi CHEN Ji-en MA You-tong FANG Liang MENG Shu-min ZHAO Xin WANG jia-bin liu Department of Materials Science and Engineering Zhejiang University College of Electrical Engineering Zhejiang University College of Materials and Environmental Engineering Hangzhou Dianzi University

目的:探索Cu-Fe合金中纳米尺寸和微米尺寸的Fe相的变形行为及区别。方法:1.通过热处理在Cu-2.5%Fe-0.2%Cr合金中得到纳米级的Fe析出相,在Cu-6%Fe中得到微米级的Fe析出相;2.通过冷拉拔手段使铜合金从棒状逐步变形成线材;3.使用光学显微... 详细信息

目的:探索Cu-Fe合金中纳米尺寸和微米尺寸的Fe相的变形行为及区别。方法:1.通过热处理在Cu-2.5%Fe-0.2%Cr合金中得到纳米级的Fe析出相,在Cu-6%Fe中得到微米级的Fe析出相;2.通过冷拉拔手段使铜合金从棒状逐步变形成线材;3.使用光学显微镜、扫描电镜和透射电镜观察微观组织,并用万能电子试验机测量抗拉强度,用标准四点法测量电阻率。结论:1.通过热处理在Cu-6%Fe合金中得到尺寸约50 nm的初生Fe颗粒,在Cu-2.5%Fe-0.2%Cr合金中得到尺寸约50 nm的次生Fe颗粒;2.初生Fe颗粒在冷拉拔过程中转变成丝带状纤维,Cu/Fe相界面密度随变形量增加而增加,从而使Cu-6%Fe合金的强度和电阻率都随之增大;3.次生Fe颗粒即使在η=6的时候也难以变形,保持着球形的形貌,同时高密度的位错环绕着Fe颗粒;Cu-2.5%Fe-0.2%Cr合金的强度随变形量增加而增大,遵循Orowan强化机制;Cu-2.5%Fe-0.2%Cr合金的电阻率几乎保持不变,因为Cu/Fe相界面密度在冷拉拔过程中几乎不变;4.尺寸效应和Fe析出颗粒与Cu基体的非共格界面对Fe析出颗粒在冷拉拔过程中不变形起到重要作用。

关键词：铜合金变形显微组织强度

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han jia Tuo liu Yuzhen Yang Jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Medical Informatics and Opportunity for Anesthesiologists

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麻醉与监护论坛 2013年第4期20卷 258-262页

作者： Ren-yu liu Meghan Lane-Fall C. William Hanson Joshua Atkins jia-bin liu Lee Fleisher Department of Anesthesiology and Critical Care Perelman School of Medicine at the University of Pennsylvania