• Title/Summary/Keyword: 경쟁종

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Kinetics and Hydrolysis Mechanism of Herbicidal N-(2,6-dimethoxypyrimidin-2-yl)aminocarbonyl-2-(1-hyd roxy-2-fluoroethyl)benzenesulfonamide Derivatives (제초성, N-(2,6-dimethoxypyrimidin-2-yl)aminocarbonyl-2-치환(Z)-6-(1-hyd roxy-2-fluoroethyl)benzenesulfonamide 유도체의 가수분해 반응 메카니즘)

  • Lee, Chan-Bog;Ryu, Jae-Wook;Kim, Dae-Whang;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.38 no.5
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    • pp.455-462
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    • 1995
  • The new six herbicidal N-[(pyrimidin-2-yl)aminocarbonyl]-2-substituted-6-(1-hydroxy-2-fluoroethyl)benzenesulfonamide derivatives(S) were synthesized and rate constants for the hydrolysis of thier in the range of pH $1.0{\sim}10.0$ have been studied in 15%(v/v) aqueous acetonitrile solution at $45^{\circ}C$. From the basis of the results, pH-effect, solvent effect, ortho-substituent effect, thermodynamic parameters(${\Delta}H^{\neq}$ & ${\Delta}S^{\neq}$), pKa constant(4.80), rate equation, analysis of hydrolysis products(2-(1-hydroxy-2-fluoroethyl)benzenesulfonamide & 4,6-dimethoxyaminopyrimidine), it may be concluded that the general acid catalyzed hydrolysis through $A-S_E2$ mechanism and specific acid catalyzed hydrolysis through A-2 type(or $A_{AC}2$) mechanism proceeds via conjugate acid($SH^+$) and tetrahedral intermediate(I) below pH 8.0, whereas, above pH 9.0, the general base catalyzed hydrolysis by water molecules(B) through $(E_1)_{anion}$ mechanism proceeds via conjugate base(CB). In the range between $pH\;7.0{\sim}pH\;9.0$, these two reactions occur competitively.

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Plant Community Structure of Pinus densiflora S. et Z. Forest in the Geumjeongsan (Mt.), Busan Metropolitan City (부산광역시 금정산 소나무림 식생구조 연구)

  • Lee, Kyoung-Jae;Kwak, Jeong-In;Kwak, Nam-Hyun;Jang, Jong-Soo
    • Korean Journal of Environment and Ecology
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    • v.27 no.4
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    • pp.462-472
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    • 2013
  • This study was carried out to provide a basic data for preservation of Pinus desiflora forest as cultural landscape forest by analyzing characteristics of plant community of P. desiflora forest in Geumjeongsan(mountatin) in Busan city. In order to analyze plant community of P. densiflora in Geumjeongsan, we set up 10 study plots inside and 8 plots outside of Geumjeongsansung(mountain fortress, hereinafter 'Sansung')(unit area: $400m^2$), a total of 18 plots. TWINSPAN analysis divided these 18 study plots into 6 communities which are Querqus serrata-P. desiflora community, P. desiflora community, P. desiflora-Q. serrata community, P. thunbergii-P. densiflora community, P. densiflora-P. thubergii-Q. acutissima community, and P. densiflora-Platycarya strobilacea community. Importance Percentage (I.P.) of each area and DBH class distribution of main species showed that P. densiflora community would succeed to Q. serrata community or C. tschonoskii community. Analysis on tree age found out that communities in the Sansung were 32~37 years old and those outside the Sansung were 44~57 years old. Shannon's species diversity index ranged from 0.4826 to 1.2499. Regarding correlation between species, P. densiflora had negative correlation with Styrax japonica. Based on abovementioned result we expected ecological succession from P. densiflora community to Q. serrata community inside of the Sansung. Outside the Sansung, succession from P. densiflora-P. thunbergii community to C. tschonoskii-Q. serrata community was expected. In order to manage P. densiflora forest as cultural landscape forest, Q. spp in the understory and shrub layer and deciduous broad-leaved arboreal trees should be managed. Tree crown management of deciduous broad-leaved trees in competition with P. desiflora, is also required.

A Table Parametric Method for Automatic Generation of Parametric CAD Models in a Mold Base e-Catalog System (몰드베이스 전자 카탈로그 시스템의 파라메트릭 CAD 모델 자동 생성을 위한 테이블 파라메트릭 방법)

  • Mun, Du-Hwan;Kim, Heung-Ki;Jang, Kwang-Sub;Cho, Jun-Myun;Kim, Jun-Hwan;Han, Soon-Hung
    • The Journal of Society for e-Business Studies
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    • v.9 no.4
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    • pp.117-136
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    • 2004
  • As the time-to-market gets more important for competitiveness of an enterprise in manufacturing industry, it becomes important to shorten the development cycle of a product. Reuse of existing design models and e-Catalog for components are required for faster product development. To achieve this goal, an electric catalog must provide parametric CAD models since parametric information is indispensable for configuration design. There are difficulties in building up a parametric library of all the necessary combination using a CAD system, since we have too many combinations of components for a product. For example, there are at least 80 million combinations of components on one page of paper catalog of a mold base. To solve this problem, we propose the method of table parametric for the automatic generation of parametric CAD models. Any combination of mold base can be generated by mapping between a classification system of an electric catalog and the design parameters set of the table parametric. We propose how to select parametric models and to construct the design parameters set.

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A Study on Index Number of Nautical Chart of Korea (한국 해도 번호체계 개선 방안에 관한 연구)

  • Kim, Jong-Sung;Lee, Hyong-Ki;Park, Young-Soo;Gang, Jeong-Gu;Park, Jin-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.17 no.3
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    • pp.219-226
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    • 2011
  • Now Korea Hydrographic and Oceanographic Administration(KHOA) publishes 309 charts of 38 kinds of scale. Korea chart index number system is established with east, south and west sea areas. The chart number has been given irregularly in accordance with publication order so there is no consistence. The present chart index number system can classify sea areas but does not have information of scale, object and location. Therefore this chart's unsystematic management gives rise to inconvenience to the chart user. So, the standards of chart index number system is urgently needed for the efficient management & use of chart. In this paper, we intend to propose new chart index number system through adjusting area of chart and rearranging scale of charts. As a result, it is necessary to change from 3 digits to 4 digits index number to gain competitiveness & systematic management of Korea nautical charts.

The Riparian Vegetation Disturbed by Two Invasive Alien Plants, Sicyos angulatus and Paspalum distichum var. indutum in South Korea (침입외래식물인 가시박과 털물참새피에 의하여 교란된 하안식생)

  • Lee, Chang Woo;Kim, Deokki;Cho, Hyunsuk;Lee, Hyohyemi
    • Ecology and Resilient Infrastructure
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    • v.2 no.3
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    • pp.255-263
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    • 2015
  • Biological invasion of alien plants is considered to be one of the most serious threats to biodiversity in riparian zones. The effects of two invasive alien plants, Sicyos angulatus and Paspalum distichum var. indutum, on the flora and community structure of the riparian vegetation were investigated at 22 sites at streams in Korea. Sicyos angulatus has invaded the central Korean Peninsula. This alien plant has caused problems to stream managers because of its aggressive vining growth. It had suppressed native vegetation such as trees, shrubs and tall grasses on bank slope and higher floodplains. Paspalum distichum var. indutum has become more widespread in the southern part of Korea. This invasive plant has shallow rhizomes and creeping, extensively branched stolons. It forms a dense mat over lotic or slowly-flowing water and threatens submerged and short emergent hydrophytes. In order to control the introduction and expansion of alien plants, limitation of artificial disturbances and appropriate alien plant management are needed in riparian areas.

Anti-oxidative Capacity of Mulberry Leaf and its Tea (뽕잎 및 뽕잎차의 항산화능)

  • Kim, Hyun-Bok;Kang, Chung-Kil;Sung, Gyoo-Byung;Kang, Seok-Woo;Lee, Jeong-Ran
    • Journal of Sericultural and Entomological Science
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    • v.49 no.1
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    • pp.18-23
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    • 2007
  • The importance of genetic resources conservation and utilization for economy and the health and well-being of societies in general is recognized all over the world. Mulberry genetic resources contain many natural components and are considerable resource for functional sericulture. We carried out antioxidative capacity analysis of mulberry leaves that were collected from Korea and some of foreign countries and preserved in the greenhouse. The mean antioxidant capacity of 34 accessions was 892.30nmol(ascorbic acid equivalent). Also we evaluated fruity characteristics and selected 4 accessions as breeding resources for the production of mulberry fruit. To investigate the effect of tea on antioxidative capacity, five kinds of tea(coffee mix, green tea added brown rice, mulberry leaf tea, Polygonatum odoratum tea and black tea added lemon) were selected and analyzed. Their's antioxidative capacity were 2,531.01nmol, 1,867.42nmol, 1,053.72nmol, 292.71nmol and 188.91nmol, respectively. The antioxidative capacity of drinking water soaked with mulberry leaf showed 891.96nmol.

플라즈마 공정 진단을 위한 공간 분해 발광 분광 분석법 소개

  • Park, Chang-Hui;Kim, Dong-Hui;Choe, Seong-Won;Lee, Chang-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.81-81
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    • 2013
  • 반도체, LCD, MEMs 등 미세 전자소자의 제작과 깊은 관련이 있는 IT 산업은 자동차 산업과 함께 세계 경제를 이끌고 있는 핵심 산업이며, 그 발전 가능성이 크다고 할 수 있다. 이 중 반도체, LCD 공정 기술에 관해서 대한민국은 세계를 선도하여 시장을 이끌어 나가고 있는 실정이다. 이들의 공정기술은 주로 높은 수율(yield)을 기반으로 한 대량 생산 기술에 초점이 맞추어져 있기 때문에, 현재와 같은 첨예한 가격 경쟁력이 요구되는 시대에서 공정 기술 개발을 통해 수율을 최대한으로 이끌어 내는 것이 현재 반도체를 비롯한 미세소자 산업이 직면하고 있는 하나의 중대한 과제라 할 수 있다. 특히 반도체공정에 있어 발전을 거듭하여 현재 20 nm 수준의 선폭을 갖는 소자들의 양산이 계획 있는데 이와 같은 나노미터급 선폭을 갖는 소자 양산과 관련된 CD (critical dimension)의 감소는 공차의 감소를 유발시키고 있으며, 패널의 양산에 있어서 생산 효율 증가를 위한 기판 크기의 대형화가 이루어지고 있다. 또한, 소자의 집적도를 높이기 위하여 높은 종횡비(aspect ratio)를 요구하는 공정이 일반화됨에 따라 단일 웨이퍼 내에서의 공정의 균일도(With in wafer uniformity, WIWU) 및 공정이 진행되는 시간에 따른 균일도(Wafer to wafer uniformity)의 변화 양상에 대한 파악을 통한 공정 진단에 대한 요구가 급증하고 있는 현실이다. 반도체 및 LCD 공정에 있어서 공정 균일도의 감시 및 향상을 위하여 박막, 증착, 식각의 주요 공정에 널리 사용되고 있는 플라즈마의 균일도(uniformity)를 파악하고 실시간으로 감시하는 것이 반드시 필요하며, 플라즈마의 균일도를 파악한다는 것은 플라즈마의 기판 상의 공간적 분포(radial direction)를 확인하여 보는 것을 의미한다. 현재까지 플라즈마의 공간적 분포를 진단하는 대표적인 방법으로는 랭뮤어 탐침(Langmuir Probe), 레이저 유도 형광법(Laser Induced Fluorescence, LIF) 그리고 광섬유를 이용한 발광분광법(Optical Emission Spectroscopy, OES)등이 있으나 랭뮤어 탐침은 플라즈마 본연의 상태에서 섭동(pertubation) 현상에 의한 교란, 이온에너지 측정의 한계로 인하여 공정의 실시간 감시에 적합하지 않으며, 레이저 유도 형광법은 측정 물질의 제한성 때문에 플라즈마 내부에 존재하는 다양한 종의 거동을 살필 수 없다는 단점 및 장치의 설치와 정렬(alignment)이 상대적으로 어려워 산업 현장에서 사용하기에 한계가 있다. 본 연구에서는 최소 50 cm에서 최대 400 cm까지 플라즈마 내 측정 거리에서 최대 20 mm 공간 분해가 가능한 광 수광 시스템 및 플라즈마 공정에서의 라디칼의 상태 변화를 분광학적 비접촉 방법으로 계측할 수 있는 발광 분광 분석기를 접목하여 플라즈마 챔버 내의 라디칼 공간 분포를 계측할 수 있는 진단 센서를 고안하고 이를 실 공정에 적용하여 보았다. 플라즈마 증착 및 식각 공정에서 형성된 박막의 두께 및 식각률과 공간 분해발광 분석법을 통하여 계측된 결과와의 매우 높은 상관관계를 확인하였다.

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The emergence and ensuing typology of global ebook platform -The case study on Google eBook, Amazon Kindle, Apple iBooks Store (글로벌 전자책 플랫폼의 부상 과정과 유형에 관한 연구 -구글 이북, 아마존 킨들, 애플 아이북스 스토어에 대한 사례연구)

  • Chang, Yong-Ho;Kong, Byoung-Hun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.8
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    • pp.3389-3404
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    • 2012
  • Based on the case study methods, the study analyzes emergence and ensuing typology of global ebook platforms such as Google eBook, Amazon Kindle, iBooks Store. Global ebook platforms show adaptation process responding to rapidly changing digital technological envirment and it's fitness landscape. The critical elements in its emerging process are the distinct selection criteria, the degree of resource abundance and the search process based on open innovation. Based on these critical elements, the global platforms show speciation process, so called niche creation and are evolving into a variety of the typology based on the initial condition of key resource which makes the platform emerge and grow. Each global ebook platforms is evolving into open platform, hybrid platform, closed platform. Google eBook has openness and extensibility due to a variety of devices based on Android and a direct involvement of actors. Amazon Kindle has developed from a online bookstore and into the hybrid platform which have not only closed quality but also openness with ebook devices and mobile network. iBooks Store has developed into the closed platform through the agency model based on competitive hardwares and closed quality with iphone and ipad.

Vegetation Type and Stand Structure of Pinus densiflora Forests in Kangwon Northern Region in Korea (강원북부지역 소나무림의 식생유형과 임분구조)

  • Lee, Kwang-Soo;Kim, Suk-Kwon;Bae, Sang-Won;Lee, Jung-Hyo;Shin, Hyun-Cheol;Jung, Mun-Ho;Moon, Hyun-Shik;Bae, Eun-Gi
    • Journal of agriculture & life science
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    • v.43 no.6
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    • pp.7-17
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    • 2009
  • The objectives of this study were to analyze vegetation type and stand structure of the red pine (Pinus densiflora) in Kangwon northern region for stable and sustainable management forests. The pine forests in study sites were classified into 3 communities, 5 groups, and 2 subgroups, total 7 vegetation units. Species with constance degree of more than 61% were P. densiflora, Quercus mongolica, Lindera obtusiloba, Spodiopogon sibiricus, Atractylodes japonica, Rhododendron mucronulatum, and Carex humilis. They were showing different characteristics by pattern according to their growing district. In the importance value (I.V.) analysis of each layer, P. densiflora showed highly in tree layer while in other layers Quercus spp. was high. Especially, young P. densiflora tree hardly appeared in the herb layer, but broad-leaved trees and shrub species showed high I.V.. Furthermore, the annual ring growth of P. densiflora was reduced while that of Q. spp. increased. According to analysis of stand structures and annual ring growths, it is considered that appropriate silvicultual practice methods should be employed to remove rival broad-leaved species for maintenance of sustainable red pine forests considering the characteristics of each stand.

Ecological Characteristic and Vegetation Structure of Pinus thunbergii Community in Coastal Forest of Busan Metropolitan City, Korea (부산광역시 해안림 곰솔군락의 식생구조 및 생태적 특성)

  • Shin, Hae-Seon;Lee, Sang-Cheol;Choi, Song-Hyun;Kang, Hyun-Mi
    • Korean Journal of Environment and Ecology
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    • v.33 no.5
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    • pp.539-551
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    • 2019
  • The purpose of this study is to understand the vegetation structure and ecological characteristics of the coastal forest Pinus thunbergii community in Busan Metropolitan City (BMC) and to establish reference information for the management of the coastal forest in BMC in the future. We set up 97 plots with an area of $100m^2$ each for the analysis and investigation of the vegetation characteristics. The analysis using the TWINSPAN and DCA techniques found seven community groups: Pinus thunbergii-Quercus aliena community, Pinus thunbergii-Eurya japonica(1) community, Pinus thunbergii-Eurya japonica(2) community, Pinus thunbergii-Quercus serrata community, Pinus thunbergii-Camellia japonica(1) community, Pinus thunbergii-Camellia japonica(2) community, and Pinus thunbergii-Eurya japonica-Camellia japonica community. According to the analysis of vegetation structure, Pinus thunbergii was a main dominant species at the canopy layer in all sites while Eurya japonica and Camellia japonica were dominant species at the understory layer. Pinus thunbergii-Quercus serrata community is predicted in the forest succession because of the competition between Pinus thunbergii and Quercus serrata in the canopy layer and the understory layer. As such, it is necessary to observe changes by continually monitoring this community. Tree species with strong salinity tolerance, including Pinus thunbergii, have formed community groups because of the environmental characteristics of coastal forests, strong with salinity tolerance species are forming community groups. Therefore, all community groups except for the Pinus thunbergii-Quercus serrata community will maintain the current vegetation structure unless drastic environmental changes occur.