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Frontiers of Chemical Science and Engineering 2016年第4期10卷 526-533页

作者： Boreum Lee Sunggeun Lee Ho young jung Shin-Kun Ryi Hankwon Lim Department of Advanced Materials and Chemical Engineering Catholic University of Daegu Gyeongbuk 38430 Korea Department of Environment and Energy Engineering C-honnam National University-Gwangju 61186 Korea Korea Institute of Energy Research Daejeon 34129 Korea

New and efficient proposed to treat perfluorinated reactor systems were compounds via catalytic decomposition. One system has a single reactor （S-1）, and another has a series of reactors （S-2）. Both systems are capable of producing a valuable CaF2 and eliminating toxic HF effluent and their feasibility was studied at various temperatures with a commercial process simulator, Aspen HYSYS. They are better than the conventional system, and S-2 is better than S-1 in terms of CaF2 production, a required heat for the system, natural gas usage and CO2 emissions in a boiler, and energy consumption. Based on process simulation results, preliminary economic analysis shows that cost savings of 12.37% and 13.55% were obtained in S-2 at 589.6 and 621.4℃compared to S-1 at 700 and 750 ℃, respectively, for the same amount of CaF2 production.

关键词： perfluorinated compounds (PFCs) CF4 pro-cess simulation economic analysis

In situ thickness control of black phosphorus field-effect transistors via ozone treatment

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Nano Research 2016年第10期9卷 3056-3065页

作者： Suhyun Kim younghun jung Jong-young Lee Gwan-Hyoung Lee Jihyun Kim Department of Chemical and Biological Engineering Korea University Seou102841 Republic of Korea Department of Materials Science and Engineering Yonsei University Seou103722 Republic of Korea

A simple and reproducible method to control the thickness of black phosphorus flakes in real time using a UV/ozone treatment is demonstrated. Back-gated black phosphorus field-effect transistors （FETs） were fabricated using thick black phosphorus flakes obtained by thinning of black phosphorus, as oxygen radicals generated by UV irradiation formed phosphorus oxides on the surface. In order to monitor the thickness effect on the electrical properties, the fabricated FETs were loaded in the UV/ozone chamber, where both the optical （micro-Raman spectroscopy and optical microscopy） and electrical properties （current-voltage characteristics） were monitored in situ. We observed an intensity decrease of the Raman modes of black phosphorus while the field-effect mobility and on/off ratio increased by 48% and 6,800%, respectively. The instability in ambient air limits the investigation and implementation of ultra-thin black phosphorus. However, the method reported in this study allowed us to start with thick black phosphorous flakes, providing a reliable approach for optimizing the electrical performance of black phosphorus-based electronic devices. We believe that these results can motivate further studies using mono- and few-layer black phosphorus.

关键词： black phosphorus in situ thinning UV/ozone treatment

Deformation prediction of porcelain-enameled steels with strain history by press forming and high-temperature behavior of coating layer

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中国有色金属学会会刊：英文版 2012年第S3期22卷 838-844页

作者： young-Ki SON Chan-Joo LEE jung-Min LEE Byung-Min KIM School of Mechanical Engineering Pusan National University Dongnam Regional Division Korea Institute of Industrial Technology

Porcelain enamel coatings were widely applied for the protection of steel products because they offered high corrosion protection,resistance to heat and abrasion,high hardness,hygiene and ease of *** typical process to produce enameled steels is roughly divided into two stages:the first stage consists of a forming process to give the desired shape to a steel substrate,and the second stage consists of a firing process to bond enamel frits on the *** firing process requires a high temperature above 800 °C,which may lead to austenitic transformation and severe thermal deformation of the steel *** aim of this study is to develop a finite element analysis (FE analysis) technique to predict the mechanical and thermal deformations of the enameled steels during forming and any further enameling process,including *** FE analysis involves analyzing the strain history of the steel substrate,which comprises the stress and thickness distributions of the substrate and its deformed shape,and the high-temperature behavior of the enamel coating *** validity of the FE analysis is verified through the U-bending test and firing test with various numbers and positions of enamel coating layers on the *** results reveal that the FE analysis results agree well with the experimental results with 8% error.

关键词： porcelain enamel firing process finite element analysis enameled steel thermal deformation

Optimal deployment schedule of an active twist rotor for performance enhancement and vibration reduction in high-speed flights

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Chinese Journal of Aeronautics 2017年第4期30卷 1427-1440页

作者： young H.YOU Sung N.jung Chang J.KIM Department of Aerospace Information Engineering Konkuk University Seoul 05019 Republic of Korea

The best active twist schedules exploiting various waveform types are sought taking advantage of the global search algorithm for the reduction of hub vibration and/or power required of a rotor in high-speed conditions. The active twist schedules include two non-harmonic inputs formed based on segmented step functions as well as the simple harmonic waveform input. An advanced Particle Swarm assisted Genetic Algorithm（PSGA） is employed for the optimizer. A rotorcraft Computational Structural Dynamics（CSD） code CAMRAD II is used to perform the rotor aeromechanics analysis. A Computation Fluid Dynamics（CFD） code is coupled with CSD for verification and some physical insights. The PSGA optimization results are verified against the parameter sweep study performed using the harmonic actuation. The optimum twist schedules according to the performance and/or vibration reduction strategy are obtained and their optimization gains are compared between the actuation cases. A two-phase non-harmonic actuation schedule demonstrates the best outcome in decreasing the power required while a four-phase non-harmonic schedule results in the best vibration reduction as well as the simultaneous reductions in the power required and vibration. The mechanism of reduction to the performance gains is identified illustrating the section airloads, angle-of-attack distribution, and elastic twist deformation predicted by the present approaches.

关键词： Active twist High-speed flight Hub vibration Non-harmonic Power required

Segmented tomographic evaluation of structural degradation of carbon support in proton exchange membrane fuel cells

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Journal of Energy Chemistry 2022年第11期31卷 359-367,I0010页

作者： jung A.Hong Min-Hyoung jung Sung Yong Cho Eun-Byeol Park Daehee Yang young-Hoon Kim Sang-Hyeok Yang Woo-Sung Jang Jae Hyuck Jang Hyo June Lee Sungchul Lee Hu young Jeong young-Min Kim Department of Energy Science Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea Fuel Cell Core Parts Development Cell Hyundai Mobis Co.Ltd.Uiwang 16082Republic of Korea Electron Microscopy&Spectroscopy Team Korea Basic Science Institute(KBSI)Daejeon 34133Republic of Korea Graduate School of Semiconductor Materials and Devices Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea

The variation of the three-dimensional(3D)structure of the membrane electrode of a fuel cell during proton exchange cycling involves the corrosion/compaction of the carbon *** increasing degradation of the carbon structure continuously reduces the electrocatalytic performance of proton exchange membrane fuel cells(PEM-FCs).This phenomenon can be explained by performing 3D tomographic analysis at the ***,conventional tomographic approaches which present limited experimental feasibility,cannot perform such evaluation and have not provided sufficient structural information with statistical significance thus ***,a reliable methodology is required for the 3D geometrical evaluation of the carbon ***,we propose a segmented tomographic approach which employs pore network analysis that enables the visualization of the geometrical parameters corresponding to the porous carbon structure at a high *** approach can be utilized to evaluate the 3D structural degradation of the porous carbon structure after cycling in terms of local surface area,pore size distribution,and their 3D *** geometrical parameters of the carbon body were demonstrated to be substantially reduced owing to the cycling-induced *** information enables a deeper understanding of the degradation phenomenon of carbon supports and can contribute to the development of stable PEM-FC electrodes.

关键词： Electron tomography Fuel cell Proton exchange membrane Membrane electrode assembly Carbon corrosion

Recurrent gastric neuroendocrine tumors treated with total gastrectomy

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World Journal of Gastroenterology 2015年第46期21卷 13195-13200页

作者： Myounghwa jung jung-Wook Kim Jae-young Jang young Woon Chang Sun Hee Park Yong Ho Kim Youn Wha Kim Department of Internal Medicine College of MedicineKyung Hee University Department of Surgery College of MedicineKyung Hee University Department of Pathology College of MedicineKyung Hee University

Gastric neuroendocrine tumors are rare; however,the incidence has recently increased due to the increasing use of upper endoscopy. Neuroendocrine tumors arise from the excess proliferation of enterochromaffinlike(ECL) cells. The proliferative changes of enterochromaffin cells evolve through a hyperplasiadysplasia-neoplasia sequence that is believed to underlie the pathogenesis of gastric neuroendocrine tumors. Endoscopic resection is recommended as the initial treatment if the tumor is not in an advanced stage. However,there is no definite guideline for the treatment of recurrent gastric neuroendocrine tumors following endoscopic resection. Here,we report a rare case of gastric neuroendocrine tumors in a 56-yearold male who experienced two recurrences within 11 years after endoscopic resection. The patient finally underwent a total gastrectomy. The pathological features of the resected stomach exhibited the full hyperplasia-dysplasia-neoplasia sequence of the ECL cells in a single specimen.

关键词： Neuroendocrine tumor Hyperplasia of neuroendocrine

Effect of Zhubin(KI9) Acupuncture in Reducing Alcohol Craving in Patients with Alcohol Dependence:A Randomized Placebo-Controlled Trial

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Chinese Journal of Integrative Medicine 2015年第4期21卷 307-311页

作者： Jin-Seong Lee Sung-Gon Kim Taek-Geun jung Woo young jung Seong-Yeon Kim Department of Psychiatry Pusan National University Yangsan Hospital Biomedical Research Institute Pusan National University Hospital Jang-Cheon Korean Medicine Clinic Division of Management Information Science(S-YK) Dong-A University

Objective： To examine the effect of acupuncture on Zhubin （KI9） in reducing alcohol craving in alcohol-dependent patients. Methods： Twenty male alcohol-dependent patients were randomly assigned to two groups, a treatment group （10 cases, age 43.0 ± 6.8 years） and a placebo group （10 cases, age 44.5 ± 7.9 years）. The treatment group was treated with real needle acupuncture on Zhubin （KI9） twice a week for 4 weeks, and the control group was treated with placebo needle acupuncture. Both groups were given acupuncture treatment using Park Sham Device （PSD）. Alcohol craving was measured by the Visual Analogue Scale （VAS） before treatment to establish a baseline, and after 1, 2, and 4 weeks of treatment. Repeated measures ANOVA was used to determine the main and interaction effects of time and on the outcome measure （VAS）. Results： There was a significant effect of time on VAS score （dr=3, F=13.3, P〈0.01）. Main effect of group on VAS score was significant （df=1, F=10.9, P〈0.01） and the time × group interaction was also significant （df=3, F=4.7, P〈0.01）. Conclusions： Real-needle acupuncture therapy on Zhubin （KI9） showed effectiveness in reducing alcohol craving. These results strongly suggest the usefulness of acupuncture therapy on Zhubin （KI9） in preventing a relapse in alcohol dependent patients.

关键词： alcohol craving alcohol dependence acupuncture Zhubin (KI9)

Collusion-resistant convertible ring signature schemes

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Science China(Information Sciences) 2015年第1期58卷 134-149页

作者： HWANG jung Yeon CHANG Ku-young CHO Hyun Sook SONG Boyeon SUSILO Willy Electronics and Telecommunications Research Institute(ETRI) DaejeonKorea Korea Institute of Science and Technology Information (KISTI) DaejeonKorea Centre for Computer and Information Security Research School of Computer Science and Software EngineeringUniversity of WollongongAustralia

A ring signature scheme provides signer ambiguity by hiding a signer in a ring of arbitrary members appropriately. A convertible ring signature scheme is an extension of a ring signature scheme that authenticates a signer and proves that a real signer and no one else generated a ring signature. In this paper, we first show that the recent convertible ring signature scheme proposed by Jeong et al. is vulnerable to collusion ***, we present a formal security model for a convertible ring signature with collusion resistance. The security notion of a convertible ring signature is intrinsically different from that of an ordinary ring signature due to the conversion property. For our collusion resistance, we consider full key exposure, that is, even an adversary who knows all secret keys will not be able to break the collusion resistance. Finally, we construct a novel convertible ring signature scheme with collusion resistance and prove the security of the scheme in the presented security model. We also compare our scheme with the existing ring signature schemes in the literature to show its advantages.

关键词： authentication ring signature anonymity convertibility collusion-resistance

Improved Hybrid Precoding Technique with Low-Resolution for MIMO-OFDM System

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Computers, Materials & Continua 2021年第8期68卷 2205-2220页

作者： Seulgi Lee Ji-Sung jung young-Hwan You Hyoung-Kyu Song Department of Information and Communication Engineering and Convergence for Intelligent DroneSejong UniversitySeoul05006Korea Department of Computer Engineering Sejong UniversitySeoul05006Korea

This paper proposes an improved hybrid beamforming system based on multiple-input multiple-output orthogonal frequency division multiplexing(MIMO-OFDM)*** proposed beamforming system improves energy efficiency compared to the conventional hybrid beamforming *** sub-connected and full-connected structure are considered to apply the proposed *** the conventional hybrid beamforming,the usage of radio frequency(RF)chains and phase shifter(PS)gives high power and hardware *** this paper,the phase over sampling(POS)with switches(SW)is used in hybrid beamforming system to improve the energy *** POS-SW structure samples the value of analog beamformer to make lower resolution than conventional *** number of output data in POS is decided by the resolution of POS *** limited number of POS decides the resolution of antenna array and the values of POSs are designed from maximum and minimum phase angle antenna *** efficiency without the phase shifter is high although channel capacity is nearly similar with conventional ***,the amplifier with POS-SW system is proposed to improve the BER *** to the data bits,the output signals of POS are *** system with 2,3 and 4 bits is simulated to prove the proposed *** order to overcome the loss of low-resolution system,the amplifier with POS-SW system using channel information is *** average sum-rate of 4 bits system shows the similar performance with the conventional hybrid beamforming *** structure can play an important role by increasing the energy efficiency of the wireless communication system that many antennas are *** is shown that the BER,average sum rate and energy efficiency of the proposed scheme are more improved than the conventional hybrid beamforming system.

关键词： Hybrid beamforming MIMO-OFDM system analog precoding POS-SW

Tendency to Avoid Physical Activity and Sport:Associations with Weight Stigma,and Psychological Distress in a Two-Wave Longitudinal Study

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International Journal of Mental Health Promotion 2024年第8期26卷 633-641页

作者： Saffari Mohsen Yi-Ching Lin Po-Ching Huang Yu-Ting Huang Ru-Yi Huang Chi Hsien Huang jung-Sheng Chen Wai Chuen Poon Mark D.Griffiths Chung-Ying Lin Health Research Center Life Style InstituteBaqiyatallah University of Medical SciencesTehran***Iran Health Education Department Faculty of HealthBaqiyatallah University of Medical SciencesTehran***Iran Department of Early Childhood and Family Education National Taipei University of EducationTaipei106TaiwanChina School of Physical Therapy Graduate Institute of Rehabilitation ScienceCollege of MedicineChang Gung UniversityTaoyuan333TaiwanChina Institute of Allied Health Sciences College of MedicineNational Cheng Kung UniversityTainan701TaiwanChina Division of Family Medicine Taipei Tzu Chi HospitalBuddhist Tzu Chi Medical Foundationand School of MedicineTzu Chi UniversityHualienTaiwanChina Data Science Degree Program National Taiwan University and Academia SinicaTaipeiTaiwanChina Department of Family Medicine and Community Medicine E-Da HospitalI-Shou UniversityKaohsiung824TaiwanChina College of Medicine I-Shou UniversityKaohsiung840Taiwan Department of Medical Research E-Da HospitalI-Shou UniversityKaohsiung840TaiwanChina Sunway Business School Sunway UniversitySelangor47500Malaysia International Gaming Research Unit Psychology DepartmentNottingham Trent UniversityNottinghamNG14BUUK Department of Public Health College of MedicineNational Cheng Kung UniversityTainan701TaiwanChina Biostatistics Consulting Center National Cheng Kung University HospitalCollege of MedicineNational Cheng Kung UniversityTainan704TaiwanChina Department of Occupational Therapy College of MedicineNational Cheng Kung UniversityTainan701TaiwanChina

Background:Physical inactivity is a major public health problem worldwide that results in physical and mental health *** major issue for physical inactivity is weight stigma(WS),especially perceived WS,which could lead to a tendency to avoid physical activity(PA).To better understand the association between perceived WS and PA,knowledge of the likely mediators in this association such as weight bias internalization(WBI)and psychological distress were investigated in the present ***:Using a two-wave longitudinal study and convenient sampling,388 Taiwan residents participants(55%females;mean age=29.7 years[SD±6.3])completed two surveys six months *** mass index(BMI),Perceived Weight Stigma Scale(PWSS),Weight Bias Internalization Scale(WBIS),Depression,Anxiety,Stress Scale(DASS-21),and Tendency to Avoid Physical Activity and Sport Scale(TAPAS)were ***:A mediation model controlling for age,gender,and BMI with 5000 bootstrapping resamples was *** WS exerted significant direct effects on WBI(β=0.25;p<0.001),psychological distress(β=0.15;p=0.003),and tendency to avoid PA(β=0.10;p=0.027);WBI exerted a significant direct effect on tendency to avoid PA(β=0.47;p<0.001).Standardized indirect effects of WBI and psychological distress on the association between perceived WS and tendency to avoid PA were 0.12 and 0.01,***:Given the direct association of perceived WS on the tendency to avoid PA and the mediating role of WBI in this association,interventions addressing perceived WS and WBI may contribute to promoting ***,health interventionists(both when planning and executing PA programs)need to consider weight stigmawhen encouraging physical activity.

关键词： Mediation model physical activity psychological distress weight stigma young adults