• Title/Summary/Keyword: site condition

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

  • Lee, Choon-Hwan
    • Journal of Plant Biology
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    • v.38 no.1
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    • pp.11-18
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    • 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.

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

  • Kang, Young-Ho;Lee, Chun-Yong;Bae, Yeong-Tae;Kim, Chan-Beom
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.6
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    • pp.1-15
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    • 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.

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

  • Zo, Sang-Soon;Lee, Sang-Hae
    • Journal of architectural history
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    • v.7 no.2 s.15
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    • pp.63-76
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    • 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.

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A Study on the Characteristic of Block Plan related to the site type of Elementary Schools (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 -)

  • Oh, Sang-Mok;Oh, Sai-Gyu
    • Journal of the Korean Institute of Educational Facilities
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    • v.10 no.4
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    • pp.31-41
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    • 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
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    • v.2 no.3
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    • pp.109-116
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    • 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.

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

  • 서정문;최인길;전영선;이종림;신재철
    • Journal of the Earthquake Engineering Society of Korea
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    • v.1 no.4
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    • pp.11-20
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    • 1997
  • The aseismic capacity of a traditional three-bay-straw-roof wooden house for rock site condition is quantitatively estimated. One 1/4 scale model was tested for the Nahanni Earthquake with peak ground accelerations from 0.1g to 0.6g. The natural frequency of the wooden house in elastic range is 1.66 Hz and 2.15 Hz in longitudinal and transversal direction, respectively. Damping ratio of the house in elastic range is 7%. The horizontal acceleration response of the house is significantly reduced compared with the input motion due to the nonlinear inelastic characteristics of the Sagae-machum joint of the frame. The traditional wooden house has high aseismic capacity in the rock site condition where high frequency contents of motion are predominant.

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

  • Yoo Neung-Soo;Nam Yun-Soo;Lee Jung-Wan
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.5-8
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    • 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.

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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
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    • v.9 no.1
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    • pp.173-194
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    • 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.

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

  • Oh, Joon-Geun;Sagong, Myung
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.16 no.2
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    • pp.125-133
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    • 2014
  • In this study, TBM selection methods to meet soil and site conditions were presented. Factors and excavation equipment affecting TBM selection by soil and environmental condition were selected and classified. Weights between equipment and influencing factors selected were calculated by applying the AHP (Analytic Hierarchy Process) method. The results of the analysis influence factors, Ground condition was a major factor in objective factors and strength was a major factor in the hard condition of criteria factors and water pressure was a major factor in the soft ground condition of criteria factors. In Environment condition, existence of adjacent structures was evaluated more important than existence of feasible site. Lastly, Adequacy was verified through the deduction of results that coincide with input equipment by applying derived weights to actual site conditions.

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

  • Son, Jong-Duk;Shim, Min-Chan;Yang, Bo-Suk
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.8
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    • pp.872-878
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    • 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.