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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B09期19卷 110-113页

作者： Myeong-hoon LEE Kyung-Man MOON Jong-Do kim Kang JUN 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

Low-frequency pulsed electromagnetic field pretreated bone marrow-derived mesenchymal stem cells promote the regeneration of crush-injured rat mental nerve

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Neural Regeneration Research 2018年第1期13卷 145-153页

作者： NaRi Seo Sung-ho Lee Kyung Won Ju JaeMan Woo BongJu kim SoungMin kim Jeong Won Jahng Jong-ho Lee Department of Oral and Maxillofacial Surgery Graduate School of Dentistry Seoul National University Seoul South Korea Department of Oral and Maxillofacial Surgery Seoul National University Dental Hospital Seoul South Korea Dental Research Institute Seoul National University Seoul South Korea Clinical Translational Research Center for Dental Science (CTRC) Seoul National University Dental Hospital Seoul South Korea

Bone marrow-derived mesenchymal stem cells （BMSCs） have been shown to promote the regeneration of injured peripheral nerves. Pulsed electromagnetic field （PEMF） reportedly promotes the proliferation and neuronal differentiation of BMSCs. Low-frequency PEMF can induce the neuronal differentiation of BMSCs in the absence of nerve growth factors. This study was designed to investigate the effects of low-frequency PEMF pretreatment on the proliferation and function of BMSCs and the effects of low-frequency PEMF pre-treated BMSCs on the regeneration of injured peripheral nerve using in vitro and in vivo *** in vitro experiments, quantitative DNA analysis was performed to determine the proliferation of BMSCs, and reverse transcription-polymerase chain reaction was performed to detect S100 （Schwann cell marker）, glial fibrillary acidic protein （astrocyte marker）, and brain-derived neurotrophic factor and nerve growth factor （neurotrophic factors） mRNA expression. In the in vivo experiments, rat models of crush-injured mental nerve established using clamp method were randomly injected with low-frequency PEMF pretreated BMSCs, unpretreated BMSCs or PBS at the injury site （1 × 106 cells）. DiI-labeled BMSCs injected at the injury site were counted under the fluorescence microscope to determine cell survival. One or two weeks after cell injection, functional recovery of the injured nerve was assessed using the sensory test with von Frey filaments. Two weeks after cell injection, axonal regeneration was evaluated using histomorphometric analysis and retrograde labeling of trigeminal ganglion neurons. In vitro experiment results revealed that low-frequency PEMF pretreated BMSCs proliferated faster and had greater mRNA expression of growth factors than unpretreated BMSCs. In vivo experiment results revealed that compared with injection of unpretreated BMSCs, injection of low-frequency PEMF pretreated BMSCs led to higher myelinated axon count and axon density and more Di

关键词： nerve regeneration mesenchymal stem cells low-frequency pulsed electromagnetic field peripheral nerve injury crush-injured mental nerve

Design of a novel 50kW fast charger for electric vehicles

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Journal of Central South University 2013年第2期20卷 372-377页

作者： YOON Hyok-min kim Jong-hyun SONG Eui-ho School of Mechatronics Changwon National University KERI 28-1 Sungju-dong

A novel 50 kW fast charger was proposed for electric vehicles. The proposed fast charger is divided into two main sections an AC-DC converter performing a PFC function and a DC-DC converter performing a charging function. A transformer including leakage inductances was used in the AC-DC converter in order to obtain isolation and inductance. A series-connection topology was used in the DC-DC converter between the DC-bus and outlet. This topology enables high power conversion efficiency up to 95% for the DC-DC converter. In order to reduce the impact of the 50 kW charging on the AC grid, the proposed fast charger system includes a buffering battery unit between the two main power conversion units. This leads to reductions in the power installation costs of power companies and to improvements in the power quality were verified through simulations and experimental results. on the AC grid. The performances of the proposed fast charger system

关键词： fast electric vehicle charger charging infrastructure buffering battery

Distribution of electric field for carbon nanotube assembly: Experiments (II)

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Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 121-125页

作者： Soongeun 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 effect of electric field on the alignment and attachment of carbon nanotubes （CNTs） were investigated. The experimental results were compared with the simulation results according to three different shaped electrodes. In previous simulation, the round shaped electrodes were expected to be more effective for aligning and attaching a single CNT between two electrodes than conical or rectangular shaped electrodes. To verify the simulation results, three different shaped electrodes were introduced and a single multi-walled carbon nanotube （MWNT） was attached. The optimal conditions for aligning and attaching MWNTs such as the frequency, applied voltage and concentration of MWNTs solution were investigated. Through repeated experiments, frequency of 100 kHz-10 MHz, applied voltage of 0.3-1.3 V^s/~m, concentration of 5 ktg/mL in MWNTs solution were obtained as a possible condition range to attach MWNTs. Under these conditions, the yield of MWNTs attachment between two electrodes was up to 70%. In previous simulation, furthermore, it was verified that the size of the stable or quasi-stable region made CNTs aligned and attached on different shaped electrodes from the comparison of the experimental and simulation results. Most single MWNT attachment was accomplished on the round shaped electrodes.

关键词： carbon nanotubes dielectrophoresis round shaped electrode simulation

A novel strategy for gas mitigation during swine manure odour treatment using seaweed and a microbial consortium

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Frontiers of Environmental Science & Engineering 2020年第3期14卷 203-214页

作者： Madhavaraj Lavanya ho-Dong Lim Kong-Min kim Dae-Hyuk kim Balasubramani Ravindran Gui Hwan Han Center for Industrialization of Agricultural and Livestock Microorganisms(CIALM) Jeongeup-si 56212Republic of Korea Department of Molecular Biology Institute for Molecular Biology and GeneticsJeonbuk National UniversityJeonju 561-756Republic of Korea Department of Environmental Energy&Engineering Kyonggi UniversitySuwon-si 16227Republic of Korea

Gas emissions from swine farms have an impact on air quality in the Republic of *** manure stored in deep pits for a long time is a major source of harmful gas ***,we evaluated the mitigation of emissions of ammonia(N H 3),hydrogen sulfide(H2S)and amine gases from swine manure with biological products such as seaweed(Sargassum homeri)and a microbial consortium(Bacillus subtilis(1.2×10^9 CFU/mL),Thiobacillus sp.(1.0×10^10 CFU/mL)and Saccharomyces cerevisiae(2.0×10^9 CFU/mL))used as additives due to their promising benefits for nutrient ***,seaweed powder masking over two days provided notable control of over 98%-100%of the gas ***,significant control of gas emissions was especially pronounced when seaweed powder masking along with a microbial consortium was applied,resulting in a gas reduction rate of 100%for NH 3,amines and H2S over 10 days of *** results also suggested that seaweed powder masking and a microbial consortium used in combination to reduce the gas emissions from swine manure reduced odour compared with that observed when the two additives were used *** the consortium,seaweed decreased total volatile fatty acid(VFA)*** proposed novel method of masking with a microbial consortium is promising for mitigating hazardous gases,simple,and environmentally *** research is warranted to determine the mechanisms underlying the seaweed and substrate interactions.

关键词： Seaweed Consortium Mitigation Ammonia H2S Volatile fatty acids(VFAs)

Optimal rotor wear design in hypotrochoidal gear pump using genetic algorithm

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Journal of Central South University 2011年第3期18卷 718-725页

作者： KWON Soon-man kim Chang-Hyun SHIN Joong-ho Department of Mechanical Design and Manufacturing Engineering Changwon National University

The wear rate between the rotors of a hypotrochoidal gear pump is *** the knowledge of shape design on the rotors,the contact stresses without hydrodynamic effect between the rotor teeth were evaluated through the calculation of the Hertzian contact *** on the above results and the sliding velocity between the rotors,a genetic algorithm (GA) was used as an optimization technique forminimizing the wear rate proportional factor (WRPF).The result shows that the wear rate or the WRPF can be reduced considerably,*** 12.8%,throughout the optimization using GA.

关键词： gerotor hypotrochoidal gear pump Hertzian contact stress wear rate proportional factor genetic algorithm

Analyzing the distinguishing factors that affect childhood obesity in South Korea

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Frontiers of Medicine 2018年第6期12卷 707-716页

作者： So Jung Yang Hun-Sung kim Kun-ho Yoon Department of Medical Informatics College of MedicineThe Catholic University of KoreaSeoul 06591Republic of Korea Division of Endocrinology and Metabolism Department of lnternal MedicineSeoul St.Mary's HospitalCollege of MedicineThe Catholic University of KoreaSeoul 06591Republic of Korea

Understanding obesity in children is crucial because it can lead to adulthood obesity and result in fatal chronic diseases. Distinctive factors associated with obesity in adults have been described, but distinctive factors related to children remain unclear. We analyzed the correlation between the percentage of body mass index and lifestyle habits by conducting surveys on physical, nutritional, and psychological factors, and we used annual physical examination data to compare different traits among elementary school students (n = 197) and middle school students (n = 461). Our study revealed that the computing hours in elementary school students with overweight and obesity were significantly correlated with the percentage of body mass index (r = 0.29 on school days and r = 0.35 on days off, all P 0.05) in the computing hours of middle school students with overweight and obesity. Childhood obesity can cause depression and reduce children's quality of life because of their distorted body perception. In conclusion, physical factors directly affecting childhood obesity and psychological and environmental factors surrounding a child should be considered.

关键词： childhood obesity eating habits percentage of body mass index quality of life screen time

An Efficient and Spam-Robust Proximity Measure Between Communication Entities

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Journal of Computer Science & Technology 2013年第2期28卷 394-400页

作者： Joo Hyuk Jeon Jihwan Song Jeong Eun Kwon Yoon Joon Lee Man ho Park Myoung ho kim Department of Computer Science Korea Advanced Institute of Science and Technology Biz Solution Team SK Telecom Information Technology R&D Center Mobile Communication Convergence Research Team Electronics and Telecommunications Research Institute

Electronic communication service providers are obliged to retain communication data for a certain amount of time by their local laws. The retained communication data or the communication logs are used in various applications such as crime detection, viral marketing, analytical study, and so on. Many of these applications rely on effective techniques for analyzing communication logs. In this paper, we focus on measuring the proximity between two communication entities, which is a fundamental and important step toward further analysis of communication logs, and propose a new proximity measure called ESP （Efficient and Spam-Robust Proximity measure）. Our proposed measure considers only the （graph- theoretically） shortest paths between two entities and gives small values to those between spam-like entities and others. Thus, it is not only computationally efficient but also spam-robust. By conducting several experiments on real and synthetic datasets, we show that our proposed proximity measure is more accurate, computationally efficient and spam-robust than the existing measures in most cases.

关键词： proximity closeness spam electronic communication

Influence of operational parameters on the photocatalytic performance of DE-NOx process Via MIL-101(Fe)

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Progress in Natural Science:Materials International 2018年第6期28卷 689-695页

作者： hoang Phuc Nguyen Tae ho kim Soo Wohn Lee Research Center for Eco Multi-Functional Nano Materials Sun Moon University Department of Environmental & Bio-Chemical Engineering Sun Moon University

Metal organic framework(MOF)has been paid great attention as a potential candidate for various applications in the field of energy and environment,particularly in air *** various MOFs,MIL-101(Fe) represents an interesting material possessing many advantages,including the ease of fabrication,high porosity,high specific surface area with open metal sites,making it a promising material in the field of harmful gas *** these advantages,MIL-101(Fe) was synthesized by facile microwave-solvothermal method and applied as a photocatalyst for the degradation of *** de-NOxefficiency of the synthesized powder was evaluated with respect to various operating parameters including substrates,sample doses,light spectrum and light intensity,initial NO concentration,and relative *** results have shown that the efficiency of NOxphotocatalytic degradation reaches to 77%under solar irradiation via 0.1 g of MIL-101(Fe) with optimum condition of reaction,(alumina substrate,350 ppb of initial NO concentration,40–50%of relative humidity).Then this work provides the optimum condition for the efficient photocatalytic degradation of NOx.

关键词： Metal-organic framework MIL-101 Gaseous pollutant NOx emission Photocatalyst