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Journal of Energy Chemistry 2019年第8期28卷 1-8,I0001页

作者： Yujin Sim Jihoon yoo Jeong-Myeong Ha Ji Chul Jung Department of Chemical Engineering Myongji UniversityYongin 17058 Republic of Korea Clean Energy Research Center Korea Institute of Science and TechnologySeoul 02792 Republic of Korea

Oxidative coupling of methane(OCM) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H values on the catalytic activity of La AlO3 catalysts in this reaction. The results showed that the co-precipitation pH value affected greatly on the formation of chemical species of precipitate precursors in the co-precipitation step, leading to different phases of the finally obtained LaAlO3 *** the co-precipitation pH value increased up to 8, the lanthanum-related phases such as La2 O3 and La(OH)3 were gradually formed as by-products, preventing the formation of LaAlO3 perovskite crystalline structure and facilitating the formation of oxygen vacancies on catalyst surface. However, at pH value of9 or higher, the lanthanum content in the precipitate precursor was increased greatly. Not LaAlO3 perovskite but lanthanum-related phases were developed as main phases, reducing their catalytic activities in this reaction. Among LaAlO3 catalysts, the one prepared at pH = 8 showed the highest C2 yield due to its well-developed oxygen vacancies and electrophilic lattice oxygen. Therefore, the co-precipitation pH value strongly affected the LaAlO3 catalyst activity in OCM reaction. A precious pH control should be required to prepare various perovskite catalysts for the OCM.

关键词： LaAlO3 Perovskite Oxidative coupling of methane Co-precipitation pH value

Neurons in the hippocampal CA1 region,but not the dentate gyrus,are susceptible to oxidative stress in rats with streptozotocin-induced type 1 diabetes

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Neural Regeneration Research 2015年第3期10卷 451-456页

作者： Sang Gun Lee Dae Young yoo Hyo Young Jung Sung Min Nam Jong Whi Kim Jung Hoon Choi Sun Shin Yi Moo-Ho Won Yeo Sung yoon In Koo Hwang Seung Myung moon Departments of Neurosurgery Dongtan Sacred Heart HospitalCollege of MedicineHallym University Department of Anatomy and Cell Biology College of Veterinary Medicineand Research Institute for Veterinary ScienceSeoul National University Department of Anatomy College of Veterinary MedicineKangwon National University Department of Biomedical Laboratory Science College of Medical SciencesSoonchunhyang University Department of Neurobiology School of MedicineKangwon National University

In this study, we investigated the effects of streptozotocin-induced type 1 diabetes on antioxi- dant-like protein-1 immunoreactivity, protein carbonyl levels, and malondialdehyde formation, a marker for lipid peroxidation, in the hippocampus. For this study, streptozotocin （75 mg/kg） was intraperitoneally injected into adult rats to induce type 1 diabetes. The three experimental pa- rameters were determined at 2, 3, 4 weeks after streptozotocin treatment. Fasting blood glucose levels significantly increased by 20.7-21.9 mM after streptozotocin treatment. The number of antioxidant-like protein-1 immunoreactive neurons significantly decreased in the hippocampal CA1 region, but not the dentate gyrus, 3 weeks after streptozotocin treatment compared to the control group. Malondialdehyde and protein carbonyl levels, which are modified by oxidative stress, significantly increased with a peak at 3 weeks after malondialdehyde treatment, and then decreased 4 weeks after malondialdehyde treatment. These results suggest that neurons in the hippocampal CA1 region, but not the dentate gyrus, are susceptible to oxidative stress 3 weeks after malondialdehyde treatment.

关键词： nerve regeneration hippocampus dentate gyrus lipid peroxidation type 1 diabetes malondialdehyde neurons neural regeneration

Sensitivity evaluation of the flash flood warning system introduced to ungauged small mountainous basins in Korea

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Journal of Mountain Science 2019年第5期16卷 971-993页

作者： yoo Chulsang LEE Jinwook CHANG Kwonhee YANG Dongmin School of Civil Environmental and Architectural Engineering College of Engineering Korea University NOAA SNC Co. Ltd.

This study evaluates the uncertainty involved in the determination of the flash flood guidance(FFG) of the flash flood warning system(FFWS) for a small mountainous region(FFWS_MR)in Korea. The sensitivity is evaluated both at each step to determine the FFG and for all steps together. The results show that the relative difference of the FFG is about 50% of the current system, most of which involves the channel width. Especially, the use of some specific empirical equations to estimate the major parameters results in a considerable amount of the relative difference of the FFG. In addition, though only four basins were field-surveyed, it is found that the indirect estimation of the major parameters always introduces some amount of additional uncertainty. In conclusion, accurate estimation of the major parameters must be the most important procedure to derive an accurate FFG, among which the channel cross-section at the exit of the basin lies at the center.

关键词： Flash flood warning system Flash flood guidance Sensitivity analysis

Error resilient concurrent video streaming over wireless mesh networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 684-695页

作者： CHUAH Chen-nee yoo Ben S.J. Electrical and Computer Engineering Department University of California Davis 95616 USA Electrical and Computer Engineering Department

In this paper, we propose a multi-source multi-path video streaming system for supporting high quality concurrent video-on-demand (VoD) services over wireless mesh networks (WMNs), and leverage forward error correction to enhance the error resilience of the system. By taking wireless interference into consideration, we present a more realistic networking model to capture the characteristics of WMNs and then design a route selection scheme using a joint rate/interference-distortion optimiza- tion framework to help the system optimally select concurrent streaming paths. We mathematically formulate such a route selec- tion problem, and solve it heuristically using genetic algorithm. Simulation results demonstrate the effectiveness of our proposed scheme.

关键词： Wireless mesh network, Concurrent video streaming, Interference

Properties of ZnO Thin Films Grown on Si (100) Substrates by Pulsed Laser Deposition

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Journal of Materials Science & Technology 2010年第11期26卷 973-976页

作者： Young Rae Jang Keon-Ho yoo Seung Min Park Department of Physics Kyung Hee University Department of Chemistry Kyung Hee University

ZnO thin films were grown on Si （100） substrates by pulsed laser deposition using a ZnO *** substrate temperature was varied in the range of room temperature to 800 ℃,and the oxygen partial pressure of 0.1333 Pa （1 m Torr） to 1333 Pa （10 Torr）.The properties of the resulting films were investigated by photoluminescence （PL）,grazing incidence X-ray diffraction （GIXRD）,X-ray photoelectron spectroscopy （XPS）,and field emission scanning electron microscopy （FESEM）.Based on the ultraviolet （UV,～380 nm） to visible emission ratio in the PL spectrum,the optimum growth conditions were determined to be 600 ℃ and 133.3 Pa （1 Torr）,*** oxygen 1s peak in the XPS spectrum was decomposed into two *** peak at lower binding energy increased in intensity with the oxygen partial pressure from 0.1333 Pa （1 m Torr） to 133.3 Pa （1 Torr） while the other peak *** GIXRD curve at the optimum condition showed strong two peaks （002） and （103）.A strong correlation between the （103） peak intensity and the UV emission intensity was found.

关键词： ZnO Pulsed laser deposition Photoluminescence

Slip-enhanced Reverse Electrodialytic Power Generation in Ion-selective Nanochannels

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Journal of Thermal Science 2013年第1期22卷 36-41页

作者： Byeongdong Kang Jaisuk yoo Hyun Jung Kim Dong-Kwon Kim Department of Mechanical Engineering Ajou University

Power generation by reverse electrodialysis in ion-selective nanochannels is numerically investigated. Especially,in the present study, the influence of hydrodynamic slip at the surface of nanochannels is investigated. The current-potential characteristics of the nanochannels are calculated by solving several governing equations:Nernst-Planck equation for the ionic concentrations, the Poisson equation for the electric potential, and the Navier-Stokes equation for the diffusioosmotic flow. Hydrodynamic slip is applied as the boundary condition at the surface of nanochannels. As the slip length increases, the diffusioosmotic flow velocity and electrical conductance of ions increase because the friction at the surface of nanochannels decreases. It is shown that the power generation is enhanced by 44% with a moderate 100nm slip length by using a nanochannel with 10nm height.

关键词：离子选择性纳米通道电渗析 Navier-Stokes方程发电控制方程渗透流速数值模拟

Effects of land use change and water reuse options on urban water cycle

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Journal of Environmental Sciences 2010年第6期22卷 923-928页

作者： Jiho Lee Gijung Pak Chulsang yoo Sangdan Kim Jaeyoung yoon School of Civil Environmentaland Architectural EngineeringKorea University Department of Environmental Engineering Korea University Department of Environmental System Engineering Pukyong National University

The aim of this article was to study the effects of land use change and water reuse options on an urban water cycle. A water cycle analysis was performed on the Goonja drainage basin, located in metropolitan Seoul, using the Aquacycle model. The chronological effects of urbanization were first assessed for the land uses of the Goonja drainage basin from 1975 to 2005, where the ratio of impervious areas ranged from 43% to 84%. Progressive urbanization was identified as leading to a decrease in evapotranspiration （29%）, an increase in surface runoff （41%） and a decrease in groundwater recharge （74%）, indicating a serious distortion of the water cycle. From a subsequent analysis of the water reuse options, such as rainwater use and wastewater reuse, it is concluded that wastewater reuse seemed to have an advantage over rainwater use for providing a consistent water supply throughout the year for a country like Korea. where the rainy season is concentrated during the summer monsoon.

关键词： Aquacycle model land use change water reuse

Nonlinear Optical Properties in a Quantum Dot of Some Polar Semiconductors

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Chinese Physics Letters 2013年第10期30卷 147-151页

作者： A.Azhagu Parvathi A.John Peter Chang Kyoo yoo Department of Physics VV Vanniaperumal College for WomenVirudhunagar-626001India Department of Physics Govt.Arts and Science CollegeMelur-625106MaduraiIndia Center for Environmental Studies/Green Energy Center Department of Environmental Science and EngineeringCollege of EngineeringKyung Hee UniversitySeocheon-dong 1Giheung-guYongin-SiGyeonggi-Do 446-701South Korea

Exciton binding energy,interband emission energy,oscillator strength,and some nonlinear optical properties in quantum dots made up of polar semiconductors are computed with the geometrical *** effects of the interaction of charge carriers with the longitudinal optical phonons on the exciton binding energy are *** anisotropy of the effective masses of holes is incorporated throughout the *** optical exciton absorption of Ⅱ–Ⅵ systems based on some polar semiconductors in the presence of LO phonons is *** optical rectification coefficient associated with the intersubband transitions in a quantum dot of polar semiconductors is *** of refractive index with the photon energy in a polar quantum dot are *** results show that the polar bound excitons in Ⅱ–Ⅵ based polar semiconductors depend on the geometrical confinement,and the nonlinear optical properties strongly depend on the polar materials.

关键词： materials Nonlinear semiconductors

Inhibitory Mechanisms of Water Extract of Oplopanax elatus on Lipopolysaccharide-lnduced Inflammatory Responses in RAW 264.7 Murine Macrophage Cells

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Chinese Journal of Integrative Medicine 2020年第9期26卷 670-676页

作者： Ki Sun Kwon Hyun Lim Yong Soo Kwon Myong Jo Kim Ji Hye yoo Nam Ho yoo Hyun Pyo Kim College of Pharmacy Kangwon National UniversityChuncheon(24341)Republic of Korea Department of Bio-Resource Sciences Kangwon National UniversityChuncheon(24341)Republic of Korea Bioherb Research Institute Kangwon National UniversityChuncheon(24341)Republic of Korea

Objective:To study the anti-inflammatory action and cellular mechanism of Oplopanax ***:A hot water extract of OE(WOE)was prepared and a major constituent,syringin,was successfully *** content in WOE was found to be 214.0 p.g/g dried plant(w/w).Their anti-inflammatory activities were examined using RAW 264.7 macrophages and a mouse model of croton oil-induced ear ***:In lipopolysaccharide(LPS)-treated RAW 264.7 cells,a mouse macrophage cell line,WOE was found to significantly and strongly inhibit cyclooxygenase-2(COX-2)-induced prostaglandin E2(PGE2)production[half maximal inhibitory concentration(IC50)=135.2μg/mL]and inducible nitric oxide synthase(iNOS)-induced NO production(IC50=242.9μg/mL).In the same condition,WOE was revealed to inhibit NO production by downregulating iNOS expression,mainly by interrupting mitogen activated protein kinases(MAPKs)/activator protein-1(AP-1)*** activation of all three major MAPKs,p38 MAPK,extracellular signal-regulated kinase(ERK),and c-Jun N-terminal kinase,was inhibited by WOE(50-300μg/mL).On the other hand,WOE reduced PGE2 production by inhibiting COX-2 enzyme activity,but did not affect COX-2 expression *** addition,WOE inhibited the production of proinflammatory cytokines such as interleukin-6 and tumor necrosis factor-α.In croton oil-induced ear edema in mice,oral administration of WOE(50-300 mg/kg)dose-dependently inhibited edematic ***:Water extract of OE exhibited multiple anti-inflammatory action mechanisms and may have potential for treating inflammatory disorders.

关键词： Oplopanax elatus Chinese medicine stem syringin anti-inflammation RAW 264.7

A Novel Goodness of Fit Test Spectrum Sensing Using Extreme Eigenvalues

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Chinese Journal of Electronics 2020年第6期29卷 1201-1206页

作者： LI He ZHAO Wenjing LIU Chang JIN Minglu yoo Sang-Jo School of Information and Communication Engineering Dalian University of Technology Department of Information and Communication Engineering Inha University

The existing Goodness of fit(GoF) test based spectrum sensing algorithms mostly use samples or energies as observations to make decisions,which can hardly achieve satisfactory performance especially when the Primary user(PU) signals are highly ***,the eigenvalue of covariance matrix can reflect signal correlations *** by this,we study the distribution of eigenvalue and propose an eigenvalue based GoF spectrum sensing *** the proposed scheme,we use the ratios of maximum to minimum eigenvalue as observations and thus it can bring performance improvements through capturing correlation of PU *** also provide the related theoretical analysis for the proposed *** results show that the proposed method overcomes the problem of noise uncertainty and achieves performance improvement over the classical samples-based GoF test.

关键词： eigenvalue based GoF spectrum sensing algorithm GoF test based spectrum sensing algorithm primary user signal covariance matrix eigenvalue Radio links and equipment eigenvalues and eigenfunctions signal detection Algebra goodness of fit test spectrum sensing algorithm Linear algebra (numerical analysis) signal sampling signal denoising radio spectrum management correlation methods covariance matrices Signal detection signal correlation