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Environmentally friendly hybrid coating prepared by electro-deposition method at various seawater conditions

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中国有色金属学会会刊：英文版 2009年第B9期19卷 110-113页

作者： Myeong-Hoon LEE Kyung-Man MOON j.ng-Do kim Kang j.N kwang-Ho kim Division of Marine System Engineering Korea Maritime University Dongsam-Dong Youngdo Busan 606-791 Korea National Core Research Center for Hybrid Materials Solution Pusan National University Busan 609-735 Korea

The formation mechanism of calcareous deposit films in seawater involves an increase in pH at the metal/solution interface due to cathodic reactions, a raised carbonate ion concentration at the interface and precipitation of inorganic deposits such as CaCO3, Mg(OH)2. Environmentally friendly hybrid calcareous deposit films were formed by an electrochemical technique on steel substrates in various solution environments. And the influence of dissolved gas on formation of calcareous deposit films was investigated by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray diffractometry(XRD). Consequently, these results showed that formation of good overall calcareous deposited films by dissolved gas in seawater environments can be achieved by controlling the material composition and structure through effective use of electrochemical method.

关键词：海水混合环保电沉积扫描电子显微镜涂层制备溶液界面

SecBCS: a secure and privacy-preserving blockchain-based crowdsourcing system

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Science China(Information Sciences) 2020年第3期63卷 20-33页

作者： Chao LIN Debiao HE Sherali ZEADALLY Neeraj.KUMAR kim-kwang Raymond CHOO Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of EducationSchool of Cyber Science and Engineering Wuhan University State Key Laboratory of Cryptology College of Communication and Information University of Kentucky Department of Computer Science and Engineering Thapar University Department of Information Systems and Cyber Security and Department of Electrical and Computer Engineering University of Texas at San Antonio

A robust and scalable crowd management infrastructure is crucial in addressing operational challenges when deploying high-density sensors and actuators in a smart city. While crowdsourcing is widely used in crowd management, conventional solutions, such as Upwork and Amazon Mechanical Turk, generally depend on a trusted third-party platform. There exist several potential security concerns(e.g., sensitive leakage, single point of failure and unfair j.dgment) in such a centralized paradigm. Hence, a recent trend in crowdsourcing is to leverage blockchain(a decentralized ledger technology) to address some of the existing limitations. A small number of blockchain-based crowdsourcing systems(BCSs) with incentive mechanisms have been proposed in the literature, but they are generally not designed with security in mind. Thus, we study the security and privacy requirements of a secure BCS and propose a concrete solution(i.e., SecBCS)with a prototype implementation based on j.ICE.

关键词： crowdsourcing blockchain secure privacy-preserving smart contract

Double cystic duct without being aware of the anatomic anomaly during laparoscopic cholecystectomy: The first case of reverse Y type anomaly

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 201-202页

作者： Suhyun Lim Chang Hwan kim kwang Yeol Paik Wook kim Department of Surgery Yeouido St.Mary’s HospitalCollege of MedicineThe Catholic University of Korea#1063-roYeongdeungpo-guSeoul 07345Korea

To the Editor:Variations in cystic duct anatomy are quite common,but double cystic ducts arising from one gallbladder is extremely rare,which have only been reported in less than 20 cases in literature[1–4].It is difficult to diagnose the anatomic anomaly preoperatively,and the rate of open conversion and post-operation complications were high due to ductal inj.ry during surgery[2].

关键词： anatomy cystic gallbladder

Propylene Polymerization by TiCl_4 Supported on Mg(OEt)_2 Activating with Ethanol/CO_2 System

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应用化学 2001年第5期18卷 310-315页

作者： Dong-hoLEE kwang-soo kim Department of Polymer Science Kyungpook UniversityTaegu 702-701Korea

In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an internal donor(ID). The chemical compositions of the activated support and the prepared catalyst were examined in detail. During the dissolution of Mg(OEt) 2 support in ethanol medium with CO 2 bubbling, the structure of support changed to magnesium hydrocarbyl carbonate, (CH 3CH 2O) 2- x Mg(O (C O) OCH 2CH 3) x ( x = 1,2). The content of carbonated CO 2 in the activated support was dependent on the heat treatment in the solidification of support. In the preparation procedure of polymerization catalyst, the activated support was treated with TiCl 4 so that the structure of support was converted to MgCl 2 with the incorporation of ID. The polymerization behavior of the pre-pared catalyst was also studied in the presence of phenyltriethoxysilane as an external donor.

关键词：丙烯催化聚合聚丙烯乙醇镁四氯化钛负载型催化剂催化活性

Effect of ZnO Electrodeposited on Carbon Film and Decorated with Metal Nanoparticles for Solar Hydrogen Production

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j.urnal of Materials Science & Technology 2016年第10期32卷 1059-1065页

作者： Young kwang kim Hye-j.n Seo Soonhyun kim Sung-Ho Hwang Hyunwoong Park Sang Kyoo Lim Division of Nano and Energy Convergence Research Daegu Gyeongbuk Institute of Science and Technology (DGIST) School of Energy Engineering Kyungpook National University

In this study, we prepared horn-like ZnO structures on carbon films（ZnO/CF） by electrodeposition and decorated the ZnO horns with different metals（Ag, Au, and Pt） via photodeposition（M-ZnO/CF）. Using M-ZnO/CF as photocatalysts, we examined ways to enhance solar hydrogen production from various points of view, such as modifying the intrinsic physical properties and thermodynamics of the materials, and varying the chemical environment during M-ZnO/CF fabrication. In particular, we focused on the effects of the carbon film and metals in M-ZnO/CF hybrid photocatalysts on solar hydrogen production. The type of metal nanoparticles is an important factor in solar hydrogen production because the deposition rate and electrical conductivity of each metal affect the proton-water reduction ability.

关键词： Solar hydrogen production ZnO horn Carbon film Metal nanoparticle Electrodeposition

A blockchain future for internet of things security： a position paper

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Digital Communications and Networks 2018年第3期4卷 149-160页

作者： Mandrita Banerj.e j.nghee Lee kim-kwang Raymond Choo Department of Electrical and Computer Engineering University of Texas at San Antonio San Antonio TX 78249 USA Department of Information Systems and Cyber Security University of Texas at San Antonio San Antonio TX 78249 USA

Internet of Things （IoT） devices are increasingly being fotmd in civilian and military contexts, ranging from smart cities and smart grids to Internet-of-Medical-Things, Internet-of-Vehicles, Internet-of-Military-Things, Internet-of- Battlefield-Things, etc. In this paper, we survey articles presenting IoT security solutions published in English since j.nuary 2016. We make a nmnber of observations, including the lack of publicly available loT datasets that can be used by the research and practitioner communities. Given the potentially sensitive nature of IoT datasets, there is a need to develop a standard for sharing IoT datasets among the research and practitioner communities and other relevant stakeholders. Thus, we posit the potential for blockehain technology in facilitating secure sharing of IoT datasets （e.g., using blockchain to ensure the integrity of shared datasets） and securing loT systems, before presenting two conceptual blockchain-based approaches. We then conclude this paper with nine potential research questions.

关键词： Blockchain Blockchain security Collaborative security Internet-of-military things dataset self-healing security Intrusion-prevention system Predictive security Predictive security

Detection of stacking orientation error of CFRP composite laminates using ultrasound waves

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中国有色金属学会会刊：英文版 2009年第B9期19卷 124-127页

作者： Sun-Kyu kim David HSU Young-Hwan SEO kwang-Hee IM Division of Mechanical System Engineering Chonbuk National University Center for Nondestructive Evaluation Iowa State University Department of Physical Education Chosun University Department of Automotive Engineering Woosuk University

A j.g was developed for generating a shear wave. A pyramid with an isosceles triangle with two 45o was made of aluminum to generate shear waves using two longitudinal transducers based on ultrasonic-polarized mechanism. Also, the signal splitter was connected to the pulser j.ck on the pulser/receiver and to the longitudinal transducers. Therefore, an experimental way was performed in order to make shear wave on the bottom of aluminum alloyed pyramid. Also, a j.g was manufactured and developed for generating a shear wave based on the computer numerical simulation. It is found that the experimentally shear wave variation of newly-designed j.g is consistent with computer numerical simulation results and shear wave ultrasonic application can be very useful to detect the defects in CFRP composites.

关键词：碳纤维复合材料误差检测超声波复合材料层板计算机数值模拟堆垛脉冲发生器信号分配器

Carcinoma in situ arising in a tubulovillous adenoma of the distal common bile duct: A case report

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World j.urnal of Gastroenterology 2008年第29期14卷 4705-4708页

作者： Bum-Soo kim Sun-Hyung j.o kwang-Ro j.o Department of Surgery East-West Neo Medical Center University of KyungHee College of Medicine149 Sangil-dong Gangdong-gu Seoul 134-727 Korea Department of Internal Medicine East-West Neo Medical Center University of KyungHee College of Medicine149 Sangil-dong Gangdong-gu Seoul 134-727 Korea

Tubulovillous adenomas are common in the colon and rectum, but are rare in the common bile duct. Biliary adenomas may produce obstructive j.undice, which can be easily confused with a malignant neoplasm or stone. We report a case of a carcinoma in situ arising in a tubulovillous adenoma of the distal common bile duct causing obstructive j.undice. A 55-year-old male presented with a 10-d history of pruritus and progressive j.undice. Abdominal sonography and computed tomography showed a mass in the distal common bile duct. Endoscopic retrograde cholangiopancreatography showed luminal narrowing of the bile duct due to a polypoid mass. Positron emission tomography demonstrated no abnormal uptake. It was thought that this mass was a malignant tumor, thus a pylorus-preserving panceaticoduodenectomy was performed. The final pathology showed a tubulovillous adenoma with carcinoma in situ of the distal common bile duct. At follow-up 8 mo later, endoscopy showed multiple polyps in the rectum, colon and stomach. The polyps were removed by endoscopic mucosal resection and shown to be tubular adenomas with high grade dysplasia. Biliary adenomas require careful follow-up for early detection of recurrence and malignant transformation.

关键词： Common bile duct Adenoma Carcinomain situ

Distribution of electric field for carbon nanotube assembly: Simulation (I)

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 117-120页

作者： Soon-Geun KWON Soo-Hyun kim kwang-Ho kim Myung-Chang KANG Hyung-Woo LEE Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Korea National Core Research Center for Hybrid Materials Solution Pusan National University

The distribution of electric field for the alignment and attachment of carbon nanotubes (CNTs) was simulated. To be attached at the desired place, the aligned and attracted CNTs should be stayed in the desired area called the stable region or the quasi-stable region for an instant where the change of electric field is minimized. Since the conical electrode has the very narrow sized quasi-stable region, few CNTs can be attached. The rectangular electrodes have a wide stable region, so lots of CNTs can be attached. The results indicate that the round electrode which has a proper sized quasi-stable region is more effective for aligning and attaching a single CNT than the conical or rectangular shaped electrodes.

关键词： carbon nanotubes (CNTs) dielectrophoresis (DEP) round shaped electrode simulation