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Crack simulation and probability analysis using irregular truss structure modeling equivalent to a continuum structure

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International Journal of Agricultural and Biological Engineering 2017年第1期10卷 234-247页

作者： won Choi Seongsoo Yoon JeongJae lee Dept.of Rural Systems Engineering College of Agriculture and Life SciencesSeoul National UniversitySeoul 151-921South Korea Dept.of Agricultural and Rural Engineering College of AgricultureLife and Environments SciencesChungbuk National UniversityChungbuk 362-763South Korea Dept.of Rural Systems Engineering Research Institute of Agriculture and Life SciencesCollege of Agriculture and Life SciencesSeoul National UniversitySeoul 151-921South Korea

The problems related to agricultural structure engineering for crack simulation and reliability analysis are complicated because its variables contain wide ranges of mean and standard *** paper describes an integrated model to perform crack simulation and reliability analysis of a continuum *** structure is assumed to be under a two-dimensional plane stress and the deformation is infinitesimal.A truss structure model that has the same behaviour as a continuum structure was developed using irregular triangle truss components where each element consists of two hinges with an axial degree of freedom at both of their ends.A Monte-Carlo simulation(MCS)was adopted for the reliability *** the length of one side of the irregular triangle mesh is shorter than the thickness of the structure,the slenderness associated with compressive failure needs to be examined only for the short *** that reason,the failure criterion suitable for the equivalent truss structure model was established by checking only axial stresses acting on truss *** nodes of the equivalent truss structure model for the structural analysis in this study consist of hinges,development of plastic hinges that occurred during crack propagation were not considered in this *** simulate the development of crack,truss members over allowable stresses of tension or compression among truss members with the largest amount of stress at each completed structural analysis time step were sequentially *** irregular triangle meshes have an uncertainty in themselves to compare with regular meshes,the equivalent truss structure model could describe crack propagation more *** failure probabilities of structures under various loads and boundary conditions had good agreement with the analytical solutions directly solved from the limit state equations expressed in the form of moments.

关键词： crack simulation probability analysis irregular truss structure model failure criteria Monte Carlo simulation

Conceptual Design for a Kerosene Fuel-rich Gas-generator of a Turbopump-fed Liquid Rocket Engine

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Journal of Thermal Science 2012年第5期21卷 428-434页

作者： Min Son Jaye Koo won Kook Cho Eun Seok lee Graduate Student Korea Aerospace UniversityGoyang Republic of Korea School of Aerospace and Mechanical Engineering Korea Aerospace UniversityGoyang Republic of Korea Korea Aerospace Research Institute Daejeon Republic of Korea

A design method for a kerosene fuel-rich gas-generator of a liquid rocket engine using turbopumps to supply propellant was performed at a conceptual level. The gas-generator creates hot gases, enabling the turbine to operate the turbopumps. A chemical non-equilibrium analysis and a droplet vaporization model were used for the estimation of the burnt gas properties and characteristic chamber length. A premixed counter-flow flame analysis was performed for the prediction of the burnt gas properties, namely the temperature, the specific heat ratio and heat capacity, and the chemical reaction time. To predict the vaporization time, the Spalding model, using a single droplet in convective condition, was used. The minimum residence time in the chamber and the characteristic length were calculated by adding the reaction time and the vaporization time. Using the characteristic length, the design methods for the fuel-rich gas-generator were established. Finally, a parametric study was achieved for the effects of the O/F ratio, mass flow rate, chamber pressure, initial droplet temperature, initial droplet diameter and initial droplet velocity.

关键词： Liquid rocket engine Conceptual design Fuel-rich gas-generator Sensitivity analysis

Mismatched effects of receptor interacting protein kinase-3 on hepatic steatosis and inflammation in nonalcoholic fatty liver disease

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World Journal of Gastroenterology 2018年第48期24卷 5477-5490页

作者： Waqar Khalid Saeed Dae won Jun Kiseok Jang Sang Bong Ahn Ju Hee Oh Yeon Ji chae Jai Sun lee Hyeon Tae Kang Department of Gastroenterology Hanyang University College of Medicine Seoul 04763 South Korea Department of Pathology Hanyang University College of Medicine Seoul 04763 South Korea Department of Internal Medicine Eulji University Daejeon 34824 South Korea Department of Translational Medicine Hanyang University College of Medicine Seoul 04763 South Korea

AIM To validate the effects of receptor interacting protein kinase-3(RIP3) deletion in non-alcoholic fatty liver disease(NAFLD) and to clarify the mechanism of *** Wild-type(WT) and RIP3 knockout(KO) mice werefed normal chow and high fat(HF) diets for 12 wk. The body weight was assessed once weekly. After 12 wk, the liver and serum samples were extracted. The liver tissue expression levels of RIP3, microsomal triglyceride transfer protein, protein disulfide isomerase, apolipoprotein-B, X-box binding protein-1, sterol regulatory element-binding protein-1c, fatty acid synthase, cluster of differentiation-36, diglyceride acyltransferase, peroxisome proliferator-activated receptor alpha, tumor necrosis factor-alpha(TNF-α), and interleukin-6 were assessed. Oleic acid treated primary hepatocytes from WT and RIP3 KO mice were stained with Nile red. The expression of inflammatory cytokines, including chemokine(C-X-C motif) ligand(CXCL) 1, CXCL2, and TNF-α, in monocytes was *** RIP3 KO HF diet fed mice showed a significant gain in body weight, and liver weight, liver to body weight ratio, and liver triglycerides were increased in HF diet fed RIP3 KO mice compared to HF diet fed WT mice. RIP3 KO primary hepatocytes also had increased intracellular fat droplets compared to WT primary hepatocytes after oleic acid treatment. RIP3 overexpression decreased hepatic fat content. Quantitative real-time polymerase chain reaction analysis showed that the expression of very-low-density lipoproteins secretion markers(microsomal triglyceride transfer protein, protein disulfide isomerase, and apolipoprotein-B) was significantly suppressed in RIP3 KO mice. The overall NAFLD Activity Score was the same between WT and RIP3 KO mice; however, RIP3 KO mice had increased fatty change and decreased lobular inflammation compared to WT mice. Inflammatory signals(CXCL1/2, TNF-α, and interleukin-6) increased after lipopolysaccharide and pancaspase inhibitor(necroptotic conditi

关键词： Necroptosis Receptor interacting protein kinase-3 Mixed lineage kinase domain-like protein Non-alcoholic fatty liver disease Steatosis

Prediction models of hepatocellular carcinoma development in chronic hepatitis B patients

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World Journal of Gastroenterology 2016年第37期22卷 8314-8321页

作者： Hye won lee Sang Hoon Ahn Department of Internal Medicine Yonsei University College of Medicine Seoul 03722 South Korea Institute of Gastroenterology Yonsei University College of Medicine Seoul 03722 South Korea Liver Cirrhosis Clinical Research Center Seoul 03722 South Korea Brain Korea 21 Project for Medical Science Seoul 03722 South Korea

Chronic hepatitis B virus(HBV) infection is a major cause of cirrhosis and hepatocellular carcinoma(HCC). Applying the same strategies for antiviral therapy and HCC surveillance to all chronic hepatitis B(CHB) patients would be a burden worldwide. To properly manage CHB patients, it is necessary to identify and classify the risk for HCC development in such patients. Several HCC risk scores based on risk factors such as cirrhosis, age, male gender, and high viral load have been used, and have negative predictive values of ≥ 95%. Most of these have been derived from, and internally validated in, treatment-na?ve Asian CHB patients. Herein, we summarized various HCC prediction models, including IPM(Individual Prediction Model), CU-HCC(Chinese University-HCC), GAG-HCC(Guide with Age, Gender, HBV DNA, Core Promoter Mutations and Cirrhosis-HCC), NGM-HCC(NomogramHCC), REACH-B(Risk Estimation for Hepatocellular Carcinoma in Chronic Hepatitis B), and Page-B score. To develop a noninvasive test of liver fibrosis, we also introduced a new scoring system that uses liver stiffness values from transient elastography, including an LSM(Liver Stiffness Measurement)-based model, LSM-HCC, and mR EACH-B(modified REACH-B).

关键词： Chronic hepatitis B Hepatocellular carcinoma Development Prediction models

Prostate only radiotherapy using external beam radiotherapy:A clinician’s perspective

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World Journal of Clinical Cases 2022年第29期10卷 10428-10434页

作者： Jeong won lee Mi Joo Chung Department of Radiation Oncology Daegu Catholic University School of MedicineDaegu 42472South Korea Department of Radiation Oncology Hanyang University Hanmaeum Changwon HospitalChangwon 51139South Korea

Prostate-only radiotherapy(PORT) is widely used as the definitive treatment for localized prostate *** cancer has an α/β ratio;therefore,radiotherapy(RT) with a large fraction size is biologically effective for tumor *** current external beam RT technique for PORT has been improved from threedimensional conformal RT to intensity-modulated,stereotactic body,and imageguided *** methods are associated with reduced radiation exposure to normal tissues,decreasing urinary and bowel *** trials have shown improved local control with dose escalation through the aforementioned methods,and the efficacy and safety of intensity-modulated and stereotactic body RTs have been ***,the management of RT in patients with prostate cancer has not been fully *** a clinician,there are several concerns regarding the RT volume and dose considering the patient’s age and ***,this review aimed to discuss the radiobiological basis and external beam technical advancements in PORT for localized prostate cancer from a clinician’s perspective.

关键词： Prostate cancer Radiotherapy Radiation dose Radiation technique Radiation volume

Effects of TiN film coating on electrochemical behaviors of nanotube formed Ti-xHf alloys

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中国有色金属学会会刊：英文版 2009年第4期19卷 857-861页

作者： Kang lee won-Gi KIM Joo-Young CHO Sang-won EUN Han-Cheol CHOE Department of Dental Materials & Research Center of Nano-Interface Activation for Biomaterials College of DentistryChosun University Department of Applied Advanced Materials Korea Polytechnic Ⅴ Colleges

Ti-xHf(x=10%,20%,30% and 40%,mass fraction) alloys were prepared by arc melting,and the microstructure was controlled for 24 h at 1 000 ℃ in argon *** formation of nanotube was conducted by anodizing on Ti-Hf alloys in 1.0 mol/L H3PO4 electrolytes with small amounts of NaF at room *** then TiN coatings were coated by DC-sputtering on the anodized *** and nanotube morphology of the alloys were examined by field emission scanning electron microscopy(FE-SEM) and X-ray diffractometry(XRD).The corrosion properties of the specimens were examined through potentiodynamic test(potential range from -1 500 to 2 000 mV) in 0.9 % NaCl solution by *** microstructure shows the acicular phase and α' phase with Hf *** amorphous oxide surface is transformed to crystalline anatase *** coated nanotube surface has a good corrosion resistance.

关键词：氮化钛涂层合金制备纳米管电化学行为薄膜包衣 0.9%NaCl溶液扫描电子显微镜微观结构

Incorporation of Parameter Uncertainty into Spatial Interpolation Using Bayesian Trans-Gaussian Kriging

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Advances in Atmospheric Sciences 2015年第3期32卷 413-423页

作者： Joon Jin SONG Soohyun Kwon Gyu won lee Department of Statistical Science Baylor UniversityUSA Department of Astronomy and Atmospheric Sciences Research and Training Team for Future Creative Astrophysicists and Cosmologist Kyungpook National UniversityRepublic of Korea

Quantitative precipitation estimation （QPE） plays an important role in meteorological and hydrological ***-based telemetered rain gauges are widely used to collect precipitation *** interpolation methods are commonly employed to estimate precipitation fields covering non-observed *** is a simple and popular geostatistical interpolation method,but it has two known problems：uncertainty underestimation and violation of *** paper tackles these problems and seeks an optimal spatial interpolation for QPE in order to enhance spatial interpolation through appropriately assessing prediction uncertainty and fulfilling the required *** this end,several methods are tested：transformation,detrending,multiple spatial correlation functions,and Bayesian *** particular,we focus on a short-term and time-specific rather than a long-term and event-specific *** paper analyzes a stratiform rain event with an embedded convection linked to the passing monsoon front on the 23 August *** from a total of 100 automatic weather stations are used,and the rainfall intensities are calculated from the difference of 15 minute accumulated rainfall observed every 1 *** one-hour average rainfall intensity is then calculated to minimize the measurement random ***-validation is carried out for evaluating the interpolation methods at regional and local *** a result,transformation is found to play an important role in improving spatial interpolation and uncertainty assessment,and Bayesian methods generally outperform traditional ones in terms of the criteria.

关键词： precipitation kriging transformation Bayesian kriging detrend Korea

Gender differences in clinical outcomes of acute myocardial infarction undergoing percutaneous coronary intervention: insights from the KAMIR-NIH Registry

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Journal of Geriatric Cardiology 2020年第11期17卷 680-693页

作者： Myunhee lee Dae-won Kim Mahn-won Park Kyusup lee Kiyuk Chang Wook Sung Chung Tae Hoon Ahn Myung Ho Jeong Seung-Woon Rha Hyo-Soo Kim Hyeon Cheol Gwon In Whan Seong Kyung Kuk Hwang Shung Chull chae Kwon-Bae Kim Young Jo Kim Kwang Soo Cha Seok Kyu Oh Jei Keon chae Ji-Hoon Jung 无 KAMIR-NIH registry investigators Division of Cardiology Daejeon St.Mary’s hospitalCollege of MedicineThe Catholic University of KoreaSeoulSouth Korea Division of Cardiology Seoul St.Mary’s hospitalCollege of MedicineThe Catholic University of KoreaSeoulSouth Korea Gachon University Gil Medical CenterIncheonSouth Korea Chonnam National University Hospital GwangjuSouth Korea d Korea University Korea University Guro Hospital SeoulSouth Korea Seoul National University Hospital SeoulSouth Korea Sungkyunkwan Universtiy Samsung Medical CenterSeoulSouth Korea Chungnam National University Hospital DaejeonSouth Korea Chungbuk National University Hospital CheongjuSouth Korea Kyungpook National University Hospital DaeguSouth Korea Keimyung University Dongsan Medical Center DaeguSouth Korea Yeungnam University Hospital DaeguSouth Korea Pusan National University Hospital BusanSouth Korea wonkwang University Hospital IksanSouth Korea Chonbuk National University Hospital JeonjuSouth Korea Institute of Toxicology DaejeonSouth Korea 不详

Background There are numerous but conflicting data regarding gender differences in outcomes following percutaneous coronary intervention(PCI). Furthermore, gender differences in clinical outcomes with acute myocardial infarction(AMI) following PCI in Asian population remain uncertain because of the under-representation of Asian in previous trials. Methods A total of 13,104 AMI patients from Korea Acute Myocardial Infarction Registry-National Institute of Health(KAMIR-NIH) between November 2011 and December 2015 were classified into male(n = 8021, 75.9%) and female(n = 2547, 24.1%). We compared the demographic, clinical and angiographic characteristics, 30-days and 1-year major adverse cardiac and cerebrovascular events(MACCE) in women with those in men after AMI by using propensity score(PS) matching. Results Compared with men, women were older, had more comorbidities and more often presented with non-ST segment elevation myocardial infarction(NSTEMI) and reduced left ventricular systolic function. Over the median follow-up of 363 days, gender differences in both 30-days and 1-year MACCE as well as thrombolysis in myocardial infarction minor bleeding risk were not observed in the PS matched population(30-days MACCE: 5.3% vs. 4.7%, log-rank P = 0.494, HR = 1.126, 95% CI: 0.800-1.585;1-year MACCE: 9.3% vs. 9.0%, log-rank P = 0.803, HR = 1.032, 95% CI: 0.802-1.328;TIMI minor bleeding: 4.9% vs. 3.9%, log-rank P = 0.215, HR = 1.255, 95% CI: 0.869-1.814). Conclusions Among Korean AMI population undergoing contemporary PCI, women, as compared with men, had different clinical and angiographic characteristics but showed similar 30-days and 1-year clinical outcomes. The risk of bleeding after PCI was comparable between men and women during one-year follow up.

关键词： Acute myocardial infarction Asian population Gender difference Percutaneous coronary intervention

Low-temperature synthesis of Fe_(2)(MoO_(4))_(3) nanosheets: A cathode for sodium ion batteries with kinetics enhancement

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Nano Research 2021年第11期14卷 3977-3987页

作者： Ha Tran Huu N.S.M.Viswanath Ngoc Hung Vu Jong-won lee won Bin Im Division of Materials Science and Engineering Hanyang University222Wangsimni-roSeongdong-guSeoul04763Republic of Korea School of Materials Science and Engineering Chonnam National University77 Yongbong-roBuk-guGwangju61186Republic of Korea Falcuty of Biotechnology Chemistry and Environmental EngineeringPhenikaa UniversityHanoi10000Vietnam A&A Green Phoenix Group Phenikaa Research and Technology Institute(PRATI)167 Hoang NganHanoi10000Vietnam Department of Energy Science and Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)333 Techno Jungang-daeroHyeonpung-eupDalseonggunDaegu42988Republic of Korea

Sodium ion batteries (SIBs) are alternatives to lithium ion batteries (LIBs), and offer some significant benefits such as cost reduction and a lower environmental impact;however, to compete with LIBs, further research is required to improve the performance of SIBs. In this study, an orthorhombic Na super ionic conductor structural Fe_(2)(MoO_(4))_(3) nanosheet with amorphous-crystalline core-shell alignment was synthesized using a facile low-temperature water-vapor-assisted solid-state reaction and applied as a cathode material for SIBs. The obtained material has a well-defined three-dimensional stacking structure, and exhibits a high specific capacity of 87.8 mAh·g^(−1) at a current density of 1 C = 91 mA·g^(−1) after 1,000 cycles, which is due to the considerable contribution of extra surface-related reaction such as the pseudo-capacitive process. This material shows significantly improved cycling and rated behavior as well as enhanced performance under high- and low-temperature conditions, as compared to the same materials prepared by the conventional high-temperature solid-state reaction. This enhancement is explained by the unique morphology in combination with the improved kinetics of the electrochemical reaction due to its lower charge transfer resistance and higher sodium ion conductivity.

关键词： low-temperature synthesis cathode sodium ion batteries kinetics Na+super ionic conductor(NASICON)