• Title/Summary/Keyword: Site Effects

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Effects of Microclimate of Different Site Types on Tree Growth in Natural Deciduous Forest (입지유형별 미기후가 천연 활엽수림의 임목 생장에 미치는 영향)

  • Shin, Man-Yong;Chung, Sang-Young;Han, Won-Sung;Lee, Don-Koo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.10 no.1
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    • pp.9-16
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    • 2008
  • In this study we investigated the effects of the microclimatic conditions on tree growth in different site types for natural deciduous forests in Korea. First, we classified all the sites into 36 types according to their aspect (east, west, south, and north), elevation (higher than 1,000 m, 700$\sim$1,000 m, and lower than 700 m), and topographical conditions (ridge, slope, and valley). For each site type, we measured diameter growth with increment borer, and then estimated periodic annual increment of diameter, height and volume. We applied a topoclimatological technique for estimating microclimatic conditions, and produced monthly climatic estimates from which 17 weather variables (including indices of warmth, coldness, and aridity) were computed for each site type. The periodic annual increments of diameter, height, and volume were then correlated by regression analysis with those weather variables to examine effects of microclimate on tree growth by site type. We found that the correlation of diameter growth by site type was significantly correlated with most weather variables except daily photoperiod. Water condition was the most important factor for the height growth. For volume growth, on the other hand, the conditions such as relatively high temperature and low humidity provided favorable environment. Our regression analysis shows that aridity index is a good predictor for tree growth including diameter, height and volume increments.

A STUDY ON METHODOLOGY FOR IDENTIFYING CORRELATIONS BETWEEN LERF AND EARLY FATALITY

  • Kang, Kyungmin;Jae, Moosung;Ahn, Kwang-Il
    • Nuclear Engineering and Technology
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    • v.44 no.7
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    • pp.745-754
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    • 2012
  • The correlations between Large Early Release Frequency (LERF) and Early Fatality need to be investigated for risk-informed application and regulation. In Regulatory Guide (RG) -1.174, while there are decision-making criteria using the measures of Core Damage Frequency (CDF) and LERF, there are no specific criteria on LERF. Since there are both huge uncertainties and large costs needed in off-site consequence calculation, a LERF assessment methodology needs to be developed, and its correlation factor needs to be identified, for risk-informed decision-making. A new method for estimating off-site consequence has been presented and performed for assessing health effects caused by radioisotopes released from severe accidents of nuclear power plants in this study. The MACCS2 code is used for validating the source term quantitatively regarding health effects, depending on the release characteristics of radioisotopes during severe accidents. This study developed a method for identifying correlations between LERF and Early Fatality and validates the results of the model using the MACCS2 code. The results of this study may contribute to defining LERF and finding a measure for risk-informed regulations and risk-informed decision-making.

Effects of Calcination Process and $ZrO_2$ Addition on the Electrical Properties of $BaTiO_3$ Ceramics (하소공정과 $ZrO_2$ 첨가량이 $BaTiO_3$의 전기적 특성에 미치는 영향)

  • 차진이;박재관;오태성;김윤호
    • Journal of the Korean Ceramic Society
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    • v.28 no.11
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    • pp.935-941
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    • 1991
  • Effects of calcination process and ZrO2 addition on the electrical properties of [(Ba0.82Sr0.08Ca0.1)O]m(Ti1-$\chi$Zr$\chi$)O2 ceramics have been investigated. With the variation of A/B-site ratio m of the dielectric formulations, sintering behavior and the resistivity after sintering in a reducing atmosphere have been affected by the calcination process. When the dielectric formulations of m=1.01 were sintered in a reducing atmosphere, the room-temperature resitivity of 109 {{{{ OMEGA }}.cm was obtained for samples processed with two-step calcination, which was much lower than 1012 {{{{ OMEGA }}.cm of samples calcined once. It was confirmed that high resistivity of Ca-doped BaTiO3 ceramics, after sintering in a reducing atmosphere, is maintained by acceptor-like behavior of CaTi" which is formed by Ca substitution to Ti-site. It was also found out that the critical amount of B-site Ca substitution for reduction inhibition of BaTiO3 is around 0.005 mol. With the increasing amount of ZrO2 addition to dielectric formulations, Curie peak was depressed and Curie temperature was lowered due to the enhanced diffuse phase transition.tion.

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Effects of Electrical Stimulation on Femoral Fracture Healing in a Dog Model (전기자극이 개의 대퇴골절 치유에 미치는 영향)

  • 박경철;이주명;윤영민;강태영;김희석;이경갑;강윤호;정종태
    • Journal of Veterinary Clinics
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    • v.20 no.3
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    • pp.328-333
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    • 2003
  • This study was performed to investigate the effects of electrical stimulation on femoral fracture healing in dogs. Eight healthy dogs from 4 to 5 $\beta^3$ were used in this experiment. In the treatment group, anode and cathode were connected to proximal and distal site apart from the fracture line by 2 cm and electrical stimulation was applied to the fracture site for l5minutes by 2 V, 25 Hz and for a month. The control group was connected to electrostimulator as the treatment group, but no electrical stimulation was applied. Various parameters were evaluated including radiograph and serum levels of total-ALP(TALP), bone-ALP(BALP) and osteocalcin. The radiography revealed more rapid callus formation in the treatment group than in the control by about a week. The total-ALP levels of the treatment group were higher than those of the control group from the 2nd to the 24th day(p< 0.05). The bone-ALP levels of the treatment group were significantly higher than those of the control from the 2nd to the 24th day(p< 0.05). The bone-ALP/ total-ALP ratios of the treatment group were higher than those of control throughout this experiment but there were no significance. There were no significance in the osteocalcin levels between two groups. In conclusion, the electrical stimulation on femoral fracture site was effective for bone healing in dogs.

Seismic Response of CWR on HSR Bridge Considering Derailment Inducing Factors (탈선취약요소를 고려한 고속철도교량 장대레일 지진응답 평가)

  • Yi, Jang-Seok;Kim, Dae-Sang
    • Journal of the Earthquake Engineering Society of Korea
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    • v.13 no.3
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    • pp.29-38
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    • 2009
  • n the event of an earthquake, additional stresses can occur in the continuous welded rails (CWR) of High-speed railway (HSR) bridges due to relative displacements at expansion joints, and this stress can cause derailment. The amplification of ground motion occurs as a result of site effects, and this is pronounced at the site of a soft surface soil layer and of a rigid surface soil layer over a soft one. As a result, the amplified ground motion leads to an amplified seismic response in HSR bridges. A change in bridge pier height affects the seismic behavior of the bridge. A HSR bridge with gravel ballast tracks will show different dynamic behavior during an earthquake than one with concrete ballast tracks. The seismic responses of HSR bridges and their CWR are analyzed considering the derailment-inducing factors.

Effects of Environmental Factors on Aeromonas spp. Population in Naktong Estuary (낙동강 하구 생태계의 환경요인과 Aeromonas spp. 분포와의 관계)

  • 전도용;권오섭;하영칠
    • Korean Journal of Microbiology
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    • v.27 no.4
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    • pp.391-397
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    • 1989
  • Population of Aeromonas and environmental parameters were investigated at three sites from August 1986, to December, 1986 in Naktong Estuary. The variation range of Aeromonas was $4.3\times10^{2}-4.6\times 10^{4}$ MPN/100ml. The result of ANOVA indicates significant differences among the populations of Aeromonas in each site. The highest population of Aeromonas occurred at site 2, and the lowest at site 3-B. To scrutinize the effects of environmental parameters on the distribution of Aeromonas spp, principal component analysis and multiple stepwise regression were used. The results showed that distribution of Aeromonas spp. was mainly influenced by outflow of freshwater and inflow of inorganic nutrients and correlated with heterotrophic bacteria, available nitrogen, fecal coliform bacteria, and temperature.

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Effects of soil improvements on distribution of the soil macroarthropods fauna (土壤 微小 節肢動物 分布에 미치는 土壤 改良制의 影響)

  • Kwak, Joon-Soo;Park, Jung-Sick;Lee, Hwa-Soo;Na, Jong-Sung;Park, Kun-Ho;Park, Bong-Joo;So, Jae-Don
    • The Korean Journal of Ecology
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    • v.15 no.1
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    • pp.67-73
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    • 1992
  • This study was carried out to investigate the effects of soil improver on the population density and composition of microarthropods in the upland which cultivated pepper consecutively. We have treated soil improver sucf as zeolite, compost, ca, sio2 , and integrated improvement i. e. treated zeolite, compost, ca, and deep cultivate ; 20 cm. We sampled soil to collect soil microarthropods from a week to 15 months after treament at each site by soil-corer and extracted 48 hours in berlese- tullgren funnel. We have classified 16 families, 35 species diversity index of soil microarthropods are highe in the integrated improver and compost site than those found in any other sites. We suggest that soil improvement effrcts of integrated improved site are influenced by compost.

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Design and Simulation of Very Low Head Axial Hydraulic Turbine with Variation of Swirl Velocity Criterion

  • Muis, Abdul;Sutikno, Priyono
    • International Journal of Fluid Machinery and Systems
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    • v.7 no.2
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    • pp.68-79
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    • 2014
  • The type of turbine developed is based on the very low head of water potential source for the electric power production. The area of research is focused for the axial water turbine that can be applied at the simple site open channel with has a very low cost and environmental impact compared to the conventional hydro installation. High efficiency of axial turbine which applied to the very low potential head will made this type of turbine can be used at wider potential site. Existing irrigation weir and river area will be the perfect site for this turbine. This paper will compare the effects of the variation of swirl velocity criterion during the design of the blade of guide vane and rotor of the turbine. Effects of the swirl velocity criterion is wider known as a vortex conditions (free vortex, force vortex and swirl velocity constant), and the free vortex is the very popular condition that applied by most of turbine designer, therefore will be interesting to do a comparison against other criterion. ANSYS Fluent will be used for simulation and to determine the predictive performance obtained by each of design criteria.

Effects of Online Product Reviews Attributes and Site Familiarity on Consumers' Loyalty in Online Product Searching Site (온라인 상품검색사이트의 이용후기 특성과 친숙성이 충성도에 미치는 영향)

  • Lee, Kook-Yong
    • The Journal of Society for e-Business Studies
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    • v.15 no.1
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    • pp.17-37
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    • 2010
  • Currently, online searching sites offer a variety of services such as just sorting by price, manufacturer, sorting by release date for sale as well as the product reviews to help and enjoy online shopping provided consumers with more shopping information. The purpose of this study is to examine the effects of online product reviews attributes (informativeness and usefulness) and familiarity on consumers' loyalty in online product searching site via trust and satisfaction. To identify these relationships, the secondary data or past studies were collected and theoretically arranged. I made the theoretical proposed model to explain the relationships between the constructs, identify the operational definitions and 8 Hypotheses were established, there was executed the survey of 175 customers. As the result of test that make the relations of used variables clear, i can get the conclusion; site familiarity and informativeness, Usefulness of online reviews have the positive effect empirically on trust building and loyalty. From the empirical test, i suggest the strategic advices in online product searching site. To increase the consumers' loyalty, it would be developed that a variety of methods and ways to raise the site familiarity and informativeness, usefulness in online product reviews. It is necessary for sticking the consumers to raise the positive trust building and satisfaction. The results of this study would help companies operating the online product searching site.

Comparative Effects on Secretion of LH, FSH, Prolactin, and Testosterone by Chronic and Direct Hypothalamic Administration of Nonylphenol to Adult Male Rats

  • Park, Kun-Suk;Jang, Won-Cheoul;Kim, Mee-Kyung;Kim, Hyung-Gun
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.2
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    • pp.215-222
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    • 1999
  • Nonylphenol (NP) is a widespread environmental pollutant that has been shown to exert both toxic and estrogenic effects on mammalian cells. As the effects of NP on the reproductive system of adult male vertebrates are virtually unknown, we investigated not only the changes of reproductive hormone secretion in serum after chronic exposure to NP but also, in order to identify the site of its action, the reproductive hormone secretion in serum 48 hours after microinfusion of NP within hypothalamic preoptic area (POA). In the chronic exposure, the luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone in serum were decreased but prolactin (PRL) concentrations were increased. The LH, FSH, and testosterone in serum were decreased through the direct infusion of NP into POA, while there was no difference in mean serum prolactin between NP and control groups. These observations suggest that NP as endocrine disruptor has modulatory effects on hypothalamo-pituitary-gonadal axis and that the site of action of NP could be hypothalamic POA.

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