• 제목/요약/키워드: site condition

검색결과 2,017건 처리시간 0.027초

Mercury-Induced Light-Dependent Alterations of Chlorophyll a Fluorescence Kinetics in Barley Leaves

  • Lee, Choon-Hwan
    • Journal of Plant Biology
    • /
    • 제38권1호
    • /
    • pp.11-18
    • /
    • 1995
  • Mercury-induced changes in Chl a fluorescence induction kinetics of scratched barley leaf segments were dependent on the presence of light. By the treatment of 50$\mu$M HgCl2 under light condition, Fm and Fp were decreased. However, they were not significantly reduced under dark condition even after 2 h of mercury treatment. Under dark condition the decrease in variable fluorescence (Fv) after P transient was blocked within 20 min of the treatment. The analysis of fast fluorescence rise curve suggests that the inhibitory site of mercury under both light and dark conditions is not at QB binding site and the inhibition does not involve the increase in inactive PSII centers. Under light condition the decrease in Fp was partially recovered by addition of 50 $\mu$M NH2OH. These results suggest that a major inhibitory site of mercury under dark condition is at the reducing side of PSII and the site under light condition is at the oxidizing side of PSII possibly in addition to the one under dark condition. Under both light and dark conditions, energy-dependent quenching(qE) was alomost completely repressed within 20 min of mercury treatment and noticible change in Fo was not observed. The qE repression is probably due to the blockage of transthylakoid ΔpH formation.

  • PDF

산림재해지 복구를 위한 주요 수종의 입지 및 재해 저항 특성 분석 (Characteristics Analysis of Site Condition and Disturbance Resistance of Tree Species for Damaged Forested Land in South Korea)

  • 강영호;이천용;배영태;김찬범
    • 한국환경복원기술학회지
    • /
    • 제14권6호
    • /
    • pp.1-15
    • /
    • 2011
  • We recently witnessed increasingly more natural disturbances on forested land. On the other hand, only limited number of nursery grown tree species are available for restoration projects. At the same time, so little on the disturbance resistance of species has been studied that a selection of right species for right site condition becomes very difficult. This study is a compilation of the site specificities and disturbance resistance of each species native to South Korea. Each species was surveyed for 11 items related to site specificities, and 12 items related to disturbance resistance including the resistance to snow damage. This study was conducted for 161 tree species from 44 families : 21 evergreen conifer species, 2 deciduous conifer species, 18 evergreen broad-leaved species, 118 deciduous broad-leaved species, and 2 monocotyledon species. This study suggests that native species in South Korea show resistance to all types of natural disturbances except drought.

필암서원(筆巖書院)의 건축(建築) 변천과정(變遷過程)에 관(關)한 연구(硏究) (A Study on the Architectural Characteristics of Pilamseowon)

  • 조상순;이상해
    • 건축역사연구
    • /
    • 제7권2호
    • /
    • pp.63-76
    • /
    • 1998
  • Seowon(書院) was an institute for education and sacrificial rite, established privately in rural villages throughout the middle period of the Chosun dynasty(1392-1910), where scholars researched classic studies, cultivated personal characters in accordance with the Neo-Confucianism, nurtured young disciples, and performed rites at a secluded shrine where spiritual tablets of honorees were housed. This study examines the architectural characteristics of Pilamseowon(筆巖書院) in Chans'seong, Chollanamdo Province, Korea. Through the study, the architectural characteristics of Pilamseowon were found as follows: First, Pilamseowon moved twice since it had been established. Second, through the moving, the area of Pilamseowon was expanded and buildings were added. Third, some buildings of Pilamseowon reflect the previous condition of the seowon site. Take Hwakyeonroo(廓然樓) as an example, which is the main entrance pavilion of Pilamseowon. Pavilion is an appropriate type of building in sloped site. Before Hwakyeonroo was moved to the present site, it was located on sloped site, where Hwakyeonroo accordingly took the pavilion type of building. Present site condition of Pilamseowon is plane, nonetheless, Hwakyeonroo has the pavilion type of building, which reflects the previous condition of the building site. Forth, Pilamseowon consists of six spatial domains and each domain has its own entrance gate to outer area.

  • PDF

초등학교(初等學校) 입지유형(立地類型)에 따른 배치특성(配置特性)에 관한 연구(硏究) - 1998년(年) 이후(以後) 광주광역시(光州廣域市)에서 발주된 당선작(當選作)을 중심(中心)으로 - (A Study on the Characteristic of Block Plan related to the site type of Elementary Schools)

  • 오상목;오세규
    • 교육시설
    • /
    • 제10권4호
    • /
    • pp.31-41
    • /
    • 2003
  • The purpose of this study is to analyze the Characteristic of Block Plans related to site types of Elementary Schools in Kangju city. With analysis of 17 elementary school plans, we reached same conclusions. First, there is a possibility of seeing 4 examples that contiguity road condition and proportion of site, neighborhood park location, district units planning, which as classification the condition to feature of location. But the condition which is considered actually from Block Plan appeared with only contiguity road condition and district units planning two onlines. Second, despite there are elements having the possibility effecting to Block Plan, some arrangement forms are repeatedly used. There is a possibility of searching for that cause that it falls in mannerism of space form, type and place when it follows the arrangement form of existing defined as school.

The Relationship Between Hydrogen Trapping Behavior and SSCC Suceptibility of API X60/65 Grade Steels

  • Lee, Jae Myung;Kim, Jin Suk;Kim, Kyoo Young
    • Corrosion Science and Technology
    • /
    • 제2권3호
    • /
    • pp.109-116
    • /
    • 2003
  • It is well known that SSCC (sulfide stress corrosion cracking) is caused by drastic ingression of hydrogen during the service and accumulation of hydrogen near the potential crack initiation site in the material. It is important to characterize the hydrogen trapping behavior to evaluate the service performance of the high strength pipeline steels. In this study. the relationship between the hydrogen trapping behavior and SSCC susceptibility is evaluated in terms of alloy composition, microstructure and carbide behavior. The hydrogen trapping behavior was measured by electrochemical hydrogen permeation test cell (Devanathan cell). The SSCC susceptibility is evaluated by constant extension rate test and constant strain lest method. The hydrogen trapping behavior is affected greatly by microstructure and nature of carbide particles. The fine TiC, and NbC in the matrix of ferritic structure acts as strong irreversible trap sites whereas the bainitic structure acts as reversible trap site. The SSCC susceptibility is closely related to not only the hydrogen trapping behavior but also the loading condition. As the activity of reversible trap site increases, SSCC susceptibility decreases under static loading condition below yield strength, whereas SSCC susceptibility increases under dynamic loading condition or above yield strength. As the activity of irreversible trap site increases. SSCC susceptibility increases regardless of loading condition. It is cased by the mixed effect of dislocation on hydrogen diffusion and trapping behavior.

전통 초가삼간 가옥의 내진성능 평가 실험(I) : 암반지반 조건 (A Test on the Aseismic Capacity of a Traditional Three-bay-straw-roof House(I) : Rock Site Condition)

  • 서정문;최인길;전영선;이종림;신재철
    • 한국지진공학회논문집
    • /
    • 제1권4호
    • /
    • pp.11-20
    • /
    • 1997
  • 우리나라 전통 초가삼간의 1/4 축소모델을 제작하여 암반지반 조건에 대한 내진성능실험을 수행하였다. Nahanni 지진파를 사용하여 최대 가속도 0.1g~0.6g 범위에서 거동을 분석하였다. 탄성한계에서 초가삼간의 고유진동수는 장방향의 경우 약 1.66Hz, 단방향의 경우 215Hz이다. 탄성한계에서의 감쇠비는 약 7%이다. 수평방향의 가속도응답은 입력에 비해 감소하며 입력가속도 수준이 증가할수록 감소율이 증가한다. 이는 사개맞춤으로 만들어진 목조 프레임의 비선형.비탄성 특성 때문이다. 전통 초가삼간 가옥은 고진동수가 지배적인 암반지반에서 매우 큰 내진성능을 나타내었다.

  • PDF

대관령 풍력실증단지 및 실증연구 소개 (Introduction to Daegwallyeong Wind Turbine Test Site and Field Test Study)

  • 유능수;남윤수;이정완
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2005년도 춘계학술대회
    • /
    • pp.5-8
    • /
    • 2005
  • This paper aims to introduce the Daegwallyeong wind turbine test site which is the first official wind turbine test site in Korea. The current status of test site, the characteristics, the projects performed and future plan of this test site are described. The results of wind condition measurements and monitoring system established by the Kangwon National University are presented. The importance of field test is also commented.

  • PDF

1D finite element artificial boundary method for layered half space site response from obliquely incident earthquake

  • Zhao, Mi;Yin, Houquan;Du, Xiuli;Liu, Jingbo;Liang, Lingyu
    • Earthquakes and Structures
    • /
    • 제9권1호
    • /
    • pp.173-194
    • /
    • 2015
  • Site response analysis is an important topic in earthquake engineering. A time-domain numerical method called as one-dimensional (1D) finite element artificial boundary method is proposed to simulate the homogeneous plane elastic wave propagation in a layered half space subjected to the obliquely incident plane body wave. In this method, an exact artificial boundary condition combining the absorbing boundary condition with the inputting boundary condition is developed to model the wave absorption and input effects of the truncated half space under layer system. The spatially two-dimensional (2D) problem consisting of the layer system with the artificial boundary condition is transformed equivalently into a 1D one along the vertical direction according to Snell's law. The resulting 1D problem is solved by the finite element method with a new explicit time integration algorithm. The 1D finite element artificial boundary method is verified by analyzing two engineering sites in time domain and by comparing with the frequency-domain transfer matrix method with fast Fourier transform.

시공여건을 반영한 TBM선정 방법에 대한 연구 (Study on the selection of TBM in consideration of field conditions)

  • 오준근;사공명
    • 한국터널지하공간학회 논문집
    • /
    • 제16권2호
    • /
    • pp.125-133
    • /
    • 2014
  • 본 연구에서는 지반 및 현장조건을 고려한 TBM 선정방법을 제시하였다. 지반, 환경, 가격조건별로 TBM 선정에 영향을 미치는 인자와 굴착장비를 선정 분류 하였다. 선정된 영향인자와 장비 간 가중치를 AHP기법을 적용하여 산정하였다. 선정된 영향인자의 분석결과 기본요소에서는 지반조건이 가장 중요한 영향요소로 확인되었으며, 세부요소로서 암반조건에서는 강도, 토사지반조건에서는 수압이 가장 중요한 인자로 확인되었다. 주변 환경조건에서는 시공성에 영향을 줄 수 있는 주변구조물 인접여부가 중요한 인자로 확인되었다. 마지막으로 도출된 각 영향인자별 가중치를 토대로 굴착현장에 적용 가능한 TBM을 선정하고 도출결과와 실제 현장에 적용된 장비의 비교를 통하여 본 연구에서 제안하는 방법에 대한 검증이 이루어 졌다.

MEMS 가속도계 기반의 기계 상태감시용 스마트센서 개발 (Development of MEMS Accelerometer-based Smart Sensor for Machine Condition Monitoring)

  • 손종덕;심민찬;양보석
    • 한국소음진동공학회논문집
    • /
    • 제18권8호
    • /
    • pp.872-878
    • /
    • 2008
  • Many industrial operations require continuous or nearly-continuous operation of machines, interruption of which can result in significant cost loss. The condition monitoring of these machines has received considerable attentions in recent years. Rapid developments in semiconductor, computing, and communication with a remote site have led to a new generation of sensor called "smart" sensors which are capable of wireless communication with a remote site. The purpose of this research is to develop a new type of smart sensor for on-line condition monitoring. This system is addressed to detect conditions that may lead to equipment failure when it is running. Moreover it will reduce condition monitoring expense using low cost MEMS accelerometer. This system is capable for signal preprocessing task and analog to digital converter which is controlled by CPU. This sensor communicates with a remote site PC using TCP/IP protocols. The developed sensor executes performance tests for data acquisition accuracy estimations.