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Bridging Real World Semantics to Model World Semantics for Taxonomy Based Knowledge Representation System

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Journal of Computer Science & Technology 2005年第3期20卷 296-308页

作者： Ju-HumKwon Chee-YangSong chang-JooMoon doo-KwonBaik DepartmentofComputerScienceandEngineering SoftwareSystemLaboratoryKoreaUniversity15-kaAnam-dongSungbuk-kuSeoul136-701Korea DepartmentofComputerScience KonkukUniversity322Danwol-dongChungju-siChungcheongbuk-do380-701Korea

As a mean to map ontology concepts, a similarity technique is *** a context dependent concept mapping is tackled, which needs contextual information fromknowledge taxonomy. Context-based semantic similarity differs from the real world similarity in thatit requires contextual information to calculate similarity. The notion of semantic coupling isintroduced to derive similarity for a taxonomy-based system. The semantic coupling shows the degreeof semantic cohesiveness for a group of concepts toward a given context. In order to calculate thesemantic coupling effectively, the edge counting method is revisited for measuring basic semanticsimilarity by considering the weighting attributes from where they affect an edge''s strength. Theattributes of scaling depth effect, semantic relation type, and virtual connection for the edgecounting are considered. Furthermore, how the proposed edge counting method could be well adaptedfor calculating context-based similarity is showed. Thorough experimental results are provided forboth edge counting and context-based similarity. The results of proposed edge counting wereencouraging compared with other combined approaches, and the context-based similarity also showedunderstandable results. The novel contributions of this paper come from two aspects. First, thesimilarity is increased to the viable level for edge counting. Second, a mechanism is provided toderive a context-based similarity in taxonomy-based system, which has emerged as a hot issue in theliterature such as Semantic Web, MDR, and other ontology-mapping environments.

关键词： semantic similarity context-based similarity edge counting semanticcoupling weighting attributes WordNet

Discharge Characteristics of Large-Area High-Power RF Ion Source for Positive and Negative Neutral Beam Injectors

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Plasma Science and Technology 2016年第12期18卷 1220-1224页

作者： doo-Hee chang Seung Ho JEONG Min PARK Tae-Seong KIM Bong-Ki jung Kwang Won LEE Sang Ryul IN Division of Nuclear Fusion Engineering & Technology Development Korea Atomic Energy Research Institute

A large-area high-power radio-frequency（RF） driven ion source was developed for positive and negative neutral beam injectors at the Korea Atomic Energy Research Institute（KAERI）. The RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of high-power RF discharge. Plasma ignition of the ion source is initiated by the injection of argongas without a starter-filament heating, and the argon-gas is then slowly exchanged by the injection of hydrogen-gas to produce pure hydrogen plasmas. The uniformities of the plasma parameter,such as a plasma density and an electron temperature, are measured at the lowest area of the driver region using two RF-compensated electrostatic probes along the direction of the shortand long-dimensions of the driver region. The plasma parameters will be compared with those obtained at the lowest area of the expansion bucket to analyze the plasma expansion properties from the driver region to the expansion region.

关键词： neutral beam injector RF ion source plasma ignition power loading plasma parameters

Emerging Technologies of Liquid Crystal Displays

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光学学报 2003年第S1期23卷 797-798页

作者： Sin-doo Lee chang-Jae Yu Jae-Hong Park Min-Sik jung School of Electrical Engineering #032 Seoul National University Kwanak P.O. Box 34 Seoul 151-742 KoreaSchool of Electrical Engineering #032 Seoul National University Kwanak P.O. Box 34 Seoul 151-742 KoreaSchool of Electrical Engineering #032 Seoul National University Kwanak P.O. Box 34 Seoul 151-742 KoreaSchool of Electrical Engineering #032 Seoul National University Kwanak P.O. Box 34 Seoul 151-742 Korea

The general features and the emerging technologies of liquid crystal displays are described from the viewpoints of wide viewing and fast response technologies. The device applications of liquid crystals for optical co... 详细信息

关键词： of in on it as LCD Emerging Technologies of Liquid Crystal Displays been mode DSG

Surface properties of Al-doped ZnO thin film before and after CF_4/Ar plasma etching

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Plasma Science and Technology 2022年第7期24卷 194-200页

作者： Young-Hee JOO Gwan-Ha KIM doo-Seung UM chang-Il KIM School of Electrical and Electronics Engineering Chung-Ang UniversitySeoul 06974Republic of Korea Department of Semiconductor Materials and Applications Korea PolytechnicSeongnam 13122Republic of Korea Department of Electrical Engineering Sejong UniversitySeoul 05006Republic of Korea

Al-doped ZnO(AZO) is considered as an alternative to transparent conductive oxide *** and achieving a stable surface are important challenges in the development and optimization of dry etching processes, which must be overcome for the application of AZO in various devices. Therefore, in this study, the etch rate and surface properties of an AZO thin film after plasma etching using the adaptive coupled plasma system were investigated. The fastest etch rate was achieved with a CF_(4)/Ar ratio of 50:50 sccm. Regardless of the ratio of CF_(4) to Ar,the transmittance of the film in the visible region exceeded 80%. X-ray photoelectron spectroscopy analysis of the AZO thin film confirmed that metal-F bonding persists on the surface after plasma etching. It was also shown that F eliminates O vacancies. Consequently, the work function and bandgap energy increased as the ratio of CF-4 increased. This study not only provides information on the effect of plasma on AZO thin film, but identifies the cause of changes in the device characteristics during device fabrication.

关键词： Al-doped ZnO plasma etching F-based plasma surface characteristics X-ray photoelectron spectroscopy ultraviolet photoelectron spectroscopy

Patterns and determinants of plant richness by elevation in a mountain ecosystem in South Korea: area, mid-domain effect,climate and productivity

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Journal of Forestry Research 2015年第4期26卷 905-917页

作者： chang-Bae Lee jung-Hwa Chun Korea Green Promotion Agency 121 DunsanbukroSeoguDaejeon 302-831Republic of Korea Division of Forest Ecology Korea Forest Research Institute57 HoegiroDongdaemunguSeoul 130-712Republic of Korea

We examined patterns of plant species richness on an elevation gradient and evaluated the effects of cli- matic variables including mean annual temperature and precipitation, area, the mid-domain effect and productivity on species richness along two transects on Mt. Seorak, South Korea. A total of 235 plant species of 72 families and 161 genera were recorded from 130 plots along the two transects. Two different patterns, monotonic decline and a unimodal shape, were observed for woody plants with the change in elevation along the two transects, whereas multimodal patterns were observed for all plant species considered together and for herbaceous plants. Area and productivity showed significant relationships with total plant richness. Climatic variables were better predictors than other variables for variation by elevation in woody plant richness, whereas productivity was a more important variable for herbaceous plant richness. Although area was an important variable for predicting species richness pat- terns, the effects differed by transect and plant group. No empirical evidence was linked to the mid-domain *** elevational patterns may characterize different groups in the same taxon and there might be fundamental differences in the mechanisms underlying these richness patterns.

关键词： Area Climatic variables Elevationalpatterns Plant richness Productivity

Diversity patterns and phylogenetic structure of vascular plants along elevational gradients in a mountain ecosystem, South Korea

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Journal of Mountain Science 2018年第2期15卷 280-295页

作者： CHUN jung-Hwa LEE chang-Bae Division of Forest Ecology National Institute of Forest Science Global Resources Division Korea Forestry Promotion Institute

Recently, a phylogenetic diversity and community structure analysis as complementary to species-centric approaches in biodiversity studies provides new insights into the processes of community assembly. In this study, we analyzed species and phylogenetic diversity and community structures for woody and herbaceous plants along two elevational transects on Mt. Baekhwa, South Korea. The species richness and phylogenetic diversity of woody plants showed monotonic declining patterns with increasing elevation along all transects, whereas herbaceous plants showed different patterns, such as no relationship and a reversed unimodal pattern, between the study transects. The main drivers of these patterns were climate and habitat variables for woody and herbaceous plants, respectively. In addition, the phylogenetic community structure primarily showed phylogenetic clustering regulated by deterministic processes, especially environmental filtering, such as climate or habitat factors, along the two transects, although herbaceous plants along a transect depicted phylogenetic randomness as a result of a neutral process. Our findings suggest that deterministic and neutral processes may simultaneously control the community structures along small-scale elevational gradients such as local transects, although the deterministic process may be the predominant type.

关键词： Community structure Deterministicprocess Elevational gradient Neutral process Phylogenetic diversity Species richness

Simple nanofabrication of a superhydrophobic and transparent biomimetic surface

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Chinese Science Bulletin 2009年第19期54卷 3613-3616页

作者： LIM Hyuneui jung Dae-Hwan NOH jung-Hyun CHOI Gyeong-Rin KIM Wan-doo Nano-Mechanical Systems Research Division Korea Institute of Machinery and Materials Biotech and Nanotech Division Ministry of Knowledge Economy

This paper describes a simple fabrication method for creating superhydrophobic and transparent glass surfaces that mimic natural surfaces such as lotus leaves, moth eyes or cicada wings. Nanostructured glass surfaces were created by a combination of colloidal lithography and plasma etching. A colloidal mask was formed simply by the spin coating of the polystyrene beads and with modification of the interparticle distance between the beads. The etching of the glasses was conducted by CF4 plasma. Tower-shaped nanostructures at an aspect ratio of 1:4 were treated using fluoroalkylsilane selfassembled monolayers (SAMs) to obtain the hydrophobic surfaces. The treated glass surfaces showed superhydrophobicity with a water contact angle of around 150° and a hexadecane contact angle of around 110°. Furthermore, the nanostructured glass was transparent to visible light.

关键词： 21世纪实验室进展聚苯乙烯

Etching characteristics and surface modification of InGaSnO thin films under Cl_(2)/Ar plasma

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Plasma Science and Technology 2023年第10期25卷 91-96页

作者： Young-Hee JOO Jae-Won CHOI Bo HOU Hyuck-In KWON doo-Seung UM chang-Il KIM Department of Electronic and Electrical Engineering Chung-Ang UniversitySeoul 06974Republic of Korea Department of Firearms and Optics Daeduk UniversityDaejeon 34111Republic of Korea School of Physics and Astronomy Cardiff UniversityCardiff CF243AAUnited Kingdom Department of Electrical Engineering Sejong UniversitySeoul 05006Republic of Korea

Indium gallium tin oxide(IGTO)thin films have the potential for high mobility and lowtemperature processing,which makes them suitable for applications such as display backplanes and high-voltage switching ***,very few studies have investigated the plasmaetching characteristics of IGTO and changes in its properties after *** this study,the etching characteristics of IGTO were investigated using Cl_(2)/Ar plasma,and changes in surface properties were *** showed that the etch rate increased with an increase in the proportion of Cl_(2),with the highest etch rate observed at 69 nm min^(-1)in pure Cl_(2)plasma with a gas flow rate of 100 ***,increased radio-frequency power caused a rise in the etch rate,while a process pressure of 15 m Torr was *** primary etching mechanism for IGTO thin films under Cl_(2)plasma was a chemical reaction,and an increased work function indicated the occurrence of defects on the *** addition,the etching process reduced the surface roughness of Cl_(2)-containing plasma,whereas the etching process in pure Ar plasma increased surface *** study contributes to a better understanding of the plasmaetching characteristics of IGTO and changes in its properties after etching,providing valuable insights for IGTO-based applications.

关键词： InGaSnO Cl2-based plasma etching mechanism surface modification plasma etching

Performance of a New Ion Source for KSTAR Tokamak Plasma Heating

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Plasma Science and Technology 2014年第6期16卷 620-624页

作者： Tae-Seong KIM Seung Ho JEONG doo Hee chang Kwang Won LEE Sang-Ryul IN Korea Atomic Energy Research Institute

In the experimental campaign of 2010 and 2011 on KSTAR, the NBI-1 system was equipped with one prototype ion source and operated successfully, providing a neutral beam power of 0.7-1.6 MW to the tokamak plasma. The new ion source planned for the 2012 KSTAR campaign had a much more advanced performance compared with the previous one. The target performance of the new ion source was to provide a neutral deuterium beam of 2 MW to the tokamak plasma. The ion source was newly designed, fabricated, and assembled in 2011. The new ion source was then conditioned up to 64 A/100 keV over a 2-hour beam extraction and performance tested at the NB test stand （NBTS） at the Korea Atomic Energy Research Institute （KAERI） in 2012. The measured optimum perveance at which the beam divergence is a minimum was about 2.5μP, and the minimum beam divergent angle was under 1.0° at 60 keV. These results indicate that the 2.0 MW neutral beam power at 100 keV required for the heating of plasma in KSTAR can be delivered by the installation of the new ion source in the KSTAR NBI-1 system.

关键词： NBI ion source KSTAR neutral beam plasma heating positive based ion