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Naturalization of Landscaping Woody Plant, Magnolia obovata Potentially Invasive Species

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Journal of Mountain Science 2015年第1期12卷 30-38页

作者： kwon oh Jung oh Choong Hyeon Graduate School Department of Biological and Environmental Science Dongguk University Department of Biological and Environmental Science Dongguk University

Magnolia obovata, a tree species native to Japan, is a traditional landscaping tree that has also been introduced to various countries. M. obovata individuals have recently emerged in non-planting areas in Korea, prompting us to investigate its distribution by establishing Dosolsan in an urban forest of Daejeon City as the target site. In order to determine its naturalization, the study explored the status of population growth by examining the diameter at breast height of the individuals, and diameter diminution quotient was calculated. Cores of the trees were collected, and the age distribution was estimated by regression analysis. Reproduction possibility was analyzed by verifying the flowerblooming and fruit-bearing. Spontaneous colonization was investigated in the other potential sites which have different location and environment, *** diameter distribution showed a reverse J-shaped curve, and the diminution quotient was ≥ 1.8. The population was composed of different generations,thus confirming the growth of the population. The distributed M. obovata grew and flowered normally,and followed a normal life cycle. The same phenomenon was observed in other planting areas,residual forests in urban or rural areas, alluvial islands, and mountain forests. The continuous spread of M. obovata in new ecosystems may be attributable to its long-term distribution by birds, relatively fast growth, and maturity time. Investigations on the naturalization and spread of M. obovata in Korea, as well as in various countries, are warranted.

关键词： Magnolia obovata Diameterdistribution Diminution quotient Invasive plant Naturalized plant

Implementation of an 8ch GbE Multiplexing Transponder

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光学学报 2003年第S1期23卷 651-652页

作者： Joon Ki Lee Hyunjae Lee yool kwon Electronics and Telecommunications Research Institute 161 Gajeong-dong Yuseong-gu Daejeon 305-350 KoreaElectronics and Telecommunications Research Institute 161 Gajeong-dong Yuseong-gu Daejeon 305-350 KoreaElectronics and Telecommunications Research Institute 161 Gajeong-dong Yuseong-gu Daejeon 305-350 Korea

We report the implementation of a transponder to transmit eight channels of a Gigabit Ethernet signal transparently in an Optical Transport Network(OTN). This transponder is based on framing technologies for Ethernet ... 详细信息

关键词： of on for OTN Implementation of an 8ch GbE Multiplexing Transponder into WDM

Small-scale multi-axial hybrid simulation of a shear-critical reinforced concrete frame

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 727-743页

作者： Vahid Sadeghian oh-Sung kwon Frank Vecchio Department of Civil Engineering University of Toronto35 St.George St.TorontoONCanada

This study presents a numerical multi-scale simulation framework which is extended to accommodate hybrid simulation （numerical-experimental integration）. The framework is enhanced with a standardized data exchange format and connected to a generalized controller interface program which facilitates communication with various types of laboratory equipment and testing configurations. A small-scale experimental program was conducted using a six degree-of-freedom hydraulic testing equipment to verify the proposed framework and provide additional data for small-scale testing of shear- critical reinforced concrete structures. The specimens were tested in a multi-axial hybrid simulation manner under a reversed cyclic loading condition simulating earthquake forces. The physical models were 1/3.23-scale representations of a beam and two columns. A mixed-type modelling technique was employed to analyze the remainder of the structures. The hybrid simulation results were compared against those obtained from a large-scale test and finite element analyses. The study found that if precautions are taken in preparing model materials and if the shear-related mechanisms are accurately considered in the numerical model, small-scale hybrid simulations can adequately simulate the behaviour of shear-critical structures. Although the findings of the study are promising, to draw general conclusions additional test data are required.

关键词： hybrid simulation small-scale testing reinforced concrete structures, shear behaviour multi-scale modelling

Experimental Analyses of Moderately High-Temperature Heat Pump Systems with R245fa and R1233zd(E)

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Energy Engineering 2022年第6期119卷 2231-2242页

作者： Ting Chen oh Kyung kwon State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou310027China Clean Energy R&D Department Korea Institute of Industrial TechnologyCheonan31056Republic of Korea

With the limited production and use of R245fa,environmentally friendly refrigerant has attracted the attention of *** to the similar thermal characteristics,R1233zd(E)is considered to be an ideal substitute for R245fa in heat pump *** this study,the performance and economic analysis of heat pump systems with R245fa and R1233zd(E)as refrigerants are carried *** results show that the total cost of R1233zd(E)system is more than 10%higher than that of R245fa system under the same heating *** the increase of condensation temperature,the heating capacity of both systems decreases,and with the increase of evaporation temperature,the heating capacity *** variation trend of coefficient of performance(COP)of the two systems is similar to that of heating *** the same operating conditions,the COP of R1233zd(E)system is 19.2%higher than that of R245fa system,and the volumetric heat capacity of R1233zd(E)is 9.0%–13.9%lower than that of *** economic analysis results show that the investment cost of R1233zd(E)system is low under the same heat load.

关键词： Heat pump R1233zd(E) R245fa performance comparison economic analysis

Improvement in the Adhesion Between Electrode of a SOFC and Ag Paste as a Current Collector by Au Deposition

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Journal of Materials Science & Technology 2015年第3期31卷 257-263页

作者： Sang Koo Jeon Seung Hoon Nahm oh Heon kwon Department of Safety Engineering Pukyong National University Center for Energy Materials Metrology Korea Research Institute or Standards and Science

This paper reports the use of Au films to improve the performance of the stacked solid oxide fuel cell(SOFC) based on the characterization of the interface and the adhesion between the electrodes of the SOFCs and the Ag paste. The specimens were manufactured to perform the experiment as follows. A Si O2 wafer with a 300 mm notch was attached to the electrodes of a SOFC by a Ag paste and Au film, which were deposited on the electrodes by sputtering for 1 min or 5 min deposition time and annealed at300 C for 1 h. The four-point bending test was performed, which resulted in the formation of an extended crack at the tip on the wafer notch, and the crack propagation was observed using a stereo microscope equipped with a charge-coupled device(CCD). Consequently, the interfacial adhesion energy and the effect of the Au film between the each electrode and the Ag paste can be evaluated. On the cathode, the interfacial adhesion energy without Au film was 2.59 J/m2(upper value) and the adhesion energy increased to 11.59 J/m2(upper value) and 15.89 J/m2(lower value) with the Au film. On the anode,the interfacial adhesion energy without Au film was 1.74 J/m2(upper value), which increased to 11.07 J/m2(upper value) and 14.74 J/m2(lower value) with the Au film. In addition, the interface areas were analyzed by scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS) to estimate the interface delamination.

关键词： Solid oxide fuel cell Au film Interfacial adhesion

Pan-TRK positive uterine sarcoma in immunohistochemistry without neurotrophic tyrosine receptor kinase gene fusions:A case report

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World Journal of Clinical Cases 2025年第2期13卷 39-49页

作者： Seungmee Lee Yu-Ra Jeon Changmin Shin Sun-Young kwon Sojin Shin Department of Obstetrics and Gynecology Keimyung University School of MedicineDaegu 42601South Korea Department of Pathology and Institute for Cancer Research Keimyung University School of MedicineDaegu 42601South Korea

BACKGROUND The classification of uterine sarcomas is based on distinctive morphological and immunophenotypic characteristics,increasingly supported by molecular genetic *** on neurotrophic tyrosine receptor kinase(NTRK)gene fusionpositive uterine sarcoma,potentially aggressive and morphologically similar to fibrosarcoma,are limited due to its recent ***-TRK immunohistochemistry(IHC)analysis serves as an effective screening tool with high sensitivity and specificity for NTRK-fusion *** SUMMARY We report a case of a malignant mesenchymal tumor originating from the uterine cervix,which was pan-TRK IHC-positive but lacked NTRK gene fusions,accompanied by a brief literature review.A 55-year-old woman presented to the emergency department with abdominal pain and distension,exhibiting significant ascites and multiple solid pelvic *** examination revealed a tumor encompassing the uterine cervix,extending to the vagina and uterine corpus.A punch biopsy of the cervix indicated NTRK sarcoma with positive immunochemical pan-TRK ***,subsequent next generation sequencing revealed no NTRK gene fusion,leading to a diagnosis of poorly differentiated,advanced-stage *** The clinical significance of NTRK gene fusion lies in potential treatment with TRK inhibitors for positive *** such rare tumors is crucial due to the potential applicability of tropomyosin receptor kinase inhibitor treatment.

关键词： Uterine sarcoma Cervical sarcoma Neurotrophic tyrosine receptor kinase gene fusion Next generation sequencing Case report

Effects of ozonation and coagulation on effluent organic matter characteristics and ultrafiltration membrane fouling

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Journal of Environmental Sciences 2014年第6期26卷 1325-1331页

作者： kwon Jeong Dae-Sung Lee Do-Gun Kim Seok-oh Ko Department of Civil Engineering Kyung Hee UniversityYongin 446-701 Korea Institute of Construction Technology KUMHO Engineering & ConstructionYongin 449-822 Korea

Effluent organic matter （EfOM） is the major cause of fouling in the low pressure membranes process for wastewater reuse. Coagulation and oxidation of biological wastewater treatment effluent have been applied for the fouling control of microfiltration membranes. However, the change in EfOM structure by pre-treatments has not been clearly identified. The changes of EfOM characteristics induced by coagulation and ozonation were investigated through size exclusion chromatography, UV/Vis spectrophotometry, fluorescence spectrophotometry and titrimetric analysis to identify the mechanisms in the reduction of ultrafiltration （UF） membrane fouling. The results indicated that reduction of flux decline by coagulation was due to modified characteristics of dissolved organic carbon （DOC） content. Total concentration of DOC was not reduced by ozonation. However, the mass fraction of the molecules with molecular weight larger than 5 kDa, fluorescence intensity, aromaticity, highly condensed chromophores, average molecular weight and soluble microbial byproducts decreased greatly after ozonation. These results indicated that EfOM was partially oxidized by ozonation to low molecular weight, highly charged compounds with abundant electron- withdrawing functional groups, which are favourable for alleviating UF membrane flux decline.

关键词： effluent organic matter fouling ultrafiltration oxidation molecular weight distribution acidity

Synthesis and Characterization of Fluoro- and Chloro-bimetallic Alkoxides as Precursors for Luminescent Metal Oxide Materials via Sol-Gel Technique

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Chinese Journal of Chemistry 2007年第7期25卷 998-1004页

作者： ATHAR.Taimur SEOK, Sang II kwon, Jeong oh Indian Institute of Chemical Technology Uppal Road Tarnaka Hyderabad (A.P.) 500007 India Advanced Materials Division Korea Research Institute of Chemical Technology 100 Jang-Dong Yuseong-Gu Daejon 305-343 Korea

Heterobimetallic alkoxides are broadly recognized as versatile precursors for luminescence materials, and efforts are being made to develop novel routes by applying the concept of geometrical molecular design, for their synthesis and to design a single source precursor suited to photoluminescent materials. Novel and new series of bimetallic alkoxides has been prepared by metathesis route. They exhibit a lower sensitivity towards hydrolysis and so they are easier to handle as compared to other alkoxides. All the compounds were characterized by elemental analysis, FT-IR and multinuclear NMR spectroscopies. FT-IR revealed that the molecular structure of these metal alkoxides was retained to a large extent in 4 ： 1 halogenated alcohol-benzene solution. The heteronuclear NMR spectroscopy provided useful information about chemical shifts for better understanding the likely structure based on interactions with their coordinate metals. The mass spectra show similar types of fragmentation pattern. SEM-EDS analyses showed consistency with the formulation. XRD patterns show an enhanced homogeneity at high temperature. TGA measurements show that thermal decomposition occured in steps that depended entirely on the chemical compositions and the synthesis routes. SEM observation reveals that the morphology and particle size strongly depend on synthesis routes for their precursors.

关键词： precursor chemistry fluoro- or chloro-bimetallic alkoxide geometric design luminescent material

Nonlinear dynamics of curved IPMC actuators undergoing electrically driven large deformations

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International Journal of Smart and Nano Materials 2012年第3期3卷 214-225页

作者： Jin-Han Jeon Choonghee Jo Il-kwon oh School of Mechanical Aerospace and Systems EngineeringKorea Advanced Institute of Science and Technology291 Daehak-roYuseong-guDaejeon 305-701Republic of Korea

The nonlinear dynamics of curved ionic polymer-metal composite(IPMC)actuators having large tip displacement and periodical jumping locomotion was investigated *** snap-through phenomena,the actuator generates much larger tip displacement and shows abrupt jumps in the transitions of upswings and downswings with low input *** curved IPMC cantilever actuators having two different constant curvatures of 0.01 mm^(−1) and 0.02 mm^(−1) were fabricated through thermal treatment from flat IPMCs,simultaneously with no residual ***-fabricated IPMC actuators were tested to evaluate the effect of initial curvature under static and dynamic electrical *** the case of the flat IPMC actuator,asymmetric characteristics in step and harmonic responses were investigated in the curved IPMC ***,at relatively higher input voltage,snap-through phenomena were observed with much larger transverse displacements and periodical abrupt jumps of the instant *** revealed jumping movements between the multiple equilibrium *** results show that optimum curvatures for better bending performance of curved cantilever IPMCs exist and that this snap-through mechanism could be applied to IPMC actuators by considering their soft and flexible properties and the geometric structures.

关键词： ionic polymer-metal composite snap-through dynamics thermal treatment actuator