• Title/Summary/Keyword: 수렴 연구

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Miocene Volcanic Rocks Over the Area of Chenonja-bong and Siru-bong, Jinhae (1): Petrography and Petrochemical Characteristics (진해 천자봉-시루봉 일원에 분포하는 마이오세 화산암 (1): 암석기재와 암석화학적 특징)

  • Ryoo, Sam-Hyung;Jeong, Yun-Gi;Lee, Sang-Won;Sung, Jong-Gyu;Ryoo, Chung-Ryul
    • The Journal of the Petrological Society of Korea
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    • v.17 no.2
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    • pp.108-131
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    • 2008
  • The Miocene andesite and basalt intruded into and/or extruded on the Cretaceous volcanic and granitic rocks over the area of Chenjabong and Sirubong in the vicinity of Jinhae, southern part of Kyongsang basin. The K-Ar ages of the younger volcanic rocks are from 16 Ma (Sirubong andesite) to 10 Ma (Cheonjabong basalt), which indicate the Miocene volcanism in the outer part of the Tertiary basin in the Korean peninsula. The volcanics are divided into Chenjabong andesite, Cheonjabong basaltic andesite, Sirubong andesite and Cheonjabong basalt. The Cheonjabong andesite is composed of phenocrysts of clinopyroxene and plagioclase ($An_{60{\sim}64}$) and groundmass with lath-like plagioclase ($An_{76{\sim}84}$) and glass. The Cheonjabong basaltic andesite is composed of plagioclase phenocryst ($An_{60{\sim}64}$) with plagioclase lath ($An_{65}$) and glass in groundmass. The Sirubong andesite is only consisted of plagiocalse lath ($An_{64{\sim}68}$) and glass with absence of phonocryst. The Cheonjabong basalt shows typical porphyritic texture with phenocrysts of olivine ($Fo_{69-84}$) and clinopyroxene. The groundmass of the Cheonjabong basalt is composed of microphenocrysts of olivine, clinopyroxene and plagioclase ($An_{66{\sim}71}$) and plagioclase laths ($An_{57{\sim}65}$) showing pillotaxitic and intergranular texture. The Cheonjabong andesite, Cheonjabong basaltic andesite, Sirubong andesite are belong to calc-alkialine but the Cheonjabong basalt is alkaline basalt. By tectonic discrimination diagrams the parental magmas of the volcanic rocks have occurred boundary.

Meiobenthic Faunal Communities of the Deep-sea Sediments in the Northeastern Pacific along a Latitudinal Transect (북동태평양 심해 퇴적물에 서식하는 중형 저서 생물군집의 위도별 특징)

  • Hyun, Jung-Ho;Choi, Jin-Woo;Lee, Kyeong-Yong;Kim, Dong-Sung
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.5 no.3
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    • pp.245-254
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    • 2000
  • This study was conducted to investigate the community structure and distributional pattern of meiobenthos in the deep sea bottoms of northeastern Pacific during July 1998. The faunal samples were collected using the multiple corer at ten stations; eight stations along the transects from 5$^{\circ}$N to 12$^{\circ}$N, and two stations in the Preservation Zone and Impact Zone of the KODOS (Korea Deep Ocean Study) area. The organic carbon content in sediments ranged from 0.79 to 1.76 mg cm$^{-3}$, and higher concentration appeared at stations in lower latitudes than 8$^{\circ}$N. The most abundant meiobenthos was nematodes and followed by foraminiferans; these two taxa comprised more than 70% of the total abundance at all stations. The most abundant meiobenthos occurred with mesh size of 0.063 nm. The maximum density of meiobenthos was 442 ind./10 cm$^2$ at station N5, and the density gradually decreased toward station N8 where the minimum density of 92 md./10 cm$^2$ was found. More than 60% of meiobenthos were distributed at surface sediment layer within 1.0 cm, and the peak abundance was found at 0-0.25 cm layer. The latitudinal distribution pattern of meiobenthos in the study area seemed to be related with the primary productivity of the surface water that is also connected to the water circulation pattern of the Pacific Ocean near the Equator, diverging at latitude of 8$^{\circ}$N and conversing at 5$^{\circ}$N.

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Effective Management of Invasive Nutria (Myocastor coypus) in the UK and the USA (영국과 미국에서 침입성 뉴트리아 (Myocastor coypus)의 효과적 관리)

  • Kil, Jihyon;Lee, Do-hun;Kim, Young-chae
    • Ecology and Resilient Infrastructure
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    • v.2 no.4
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    • pp.265-273
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    • 2015
  • It is the better to take preventative measures against the natural intrusion in advance from invasive alien species that reduce biodiversity and cause economic loss to humans. If the prevention of intrusion and spread fails, we need to make active control and eradication. This study aims to introduce nutria (Myocastor coypus) control cases performed in the United Kingdom and the United States and to provide information for the contribution of nutria management measure improvements. The nutria eradication campaign in the United Kingdom was developed as a long-term plan based on sufficient understanding on the management target and objective and suitable support. Sufficient information on nutria was accumulated and the management strategy was flexibly modified according to the changes in management that were proactively reflected in the field. Regarding the eradication project at Chesapeake Bay in the United States, based on long-term ecological information, more advanced capture technology than in the United Kingdom were introduced and the eradication plan, strategy and implementation were configured by analyzing the strengths and weaknesses of the eradication campaign in the United Kingdom. The successful cases in the United Kingdom and the United State provide an information on how to improv the nutria management measure. For the eradication of nutria, it is necessary to reach a consensus between stakeholders and to form a consultative group between related organizations for periodic communication. Opinions on the field must be actively accepted in the consultation process for strategy and policy decision, and the eradication plan needs to be developed based on a management index. The eradication plan is required to be managed, evaluated and adjusted in a systematic way. Scientific management must be introduced and the management performance must be evaluated objectively so that a practical plan can be flexibly adjusted. It is also required to secure a long-term budget support and a stable organization and to input a concentrated budget at the proper period when there is high efficiency of eradication.

Applicability of Theoretical Adsorption Models for Studies on Adsorption Properties of Adsorbents(III) (흡착제의 흡착특성 규명을 위한 흡착모델의 적용성 평가(III) - 열역학적 특성을 중심으로)

  • Na, Choon-Ki;Jeong, Jin-Hwa;Park, Hyun-Ju
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.4
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    • pp.260-269
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    • 2012
  • The aim of this study is to evaluate the applicability of adsorption models for understanding the thermodynamic properties of adsorption process. For this study, the adsorption isotherm data of $NO_3$-N ion onto a commercial anion exchange resin obtained at various experimental conditions, i.e. different initial concentrations of adsorbate, different dosages of adsorbent, and different temperatures, were used in calculating the thermodynamic parameters and the adsorption energy of adsorption process. The Gibbs free energy change (${\Delta}G^0$) of adsorption process could be calculated using the Langmuir constant $b_M$ as well as the Sips constant, even though the results were significantly dependant on the experimental conditions. The thermodynamic parameters such as standard enthalpy change (${\Delta}H^0$), standard entropy change (${\Delta}S^0$) and ${\Delta}G^0$ could be calculated by using the experimental data obtained at different temperatures, if the adsorption data well fitted to the Langmuir isotherm model and the plot of ln b versus 1/T gives a straight line. As an alternative, the empirical equilibrium constant(K) defined as $q_e/C_e$ could be used for evaluating the thermodynamic parameters instead of the Langmuir constant. The results from the applications of D-R model and Temkin model to evaluate the adsorption energy suggest that the D-R model is better than Temkin model for describing the experimental data, and the availability of Temkin model is highly limited by the experimental conditions. Although adsorption energies determined using D-R model show significantly different values depending on the experimental conditions, they were sufficient to show that the adsorption of $NO_3$-N onto anion exchange resin is an endothermic process and an ion-exchange process.

Rietveld Structure Refinement of Biotite Using Neutron Powder Diffraction (중성자분말회절법을 이용한 흑운모의 Rietveld Structure Refinement)

  • 전철민;김신애;문희수
    • Economic and Environmental Geology
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    • v.34 no.1
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    • pp.1-12
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    • 2001
  • The crystal structure of biotite-1M from Bancroft, Ontario, was determined by Rietveld refinement method using high-resolution neutron powder diffraction data at -26.3$^{\circ}C$, 2$0^{\circ}C$, 30$0^{\circ}C$, $600^{\circ}C$, 90$0^{\circ}C$. The crystal structure has been refined to a R sub(B) of 5.06%-11.9% and S (Goodness of fitness) of 2.97-3.94. The expansion rate of a, b, c unit cell dimensions with elevated temperature linearly increase to $600^{\circ}C$. The expansivity of the c dimension is $1.61{\times}10^{40}C^{-1}$, while $2.73{\times}10^{50}C^{-1}$ and $5.71{\times}10^{-50}C^{-1}$ for the a and b dimensions, respectively. Thus, the volume increase of the unit cell is dominated by expansion of the c axis as increasing temperature. In contrast to the trend, the expansivity of the dimensions is decreased at 90$0^{\circ}C$. It may be attributed to a change in cation size caused by dehydroxylation-oxidation of $Fe^{2+}$ to $Fe^{3+}$ in vacuum condition at such high temperature. The position of H-proton was determined by the refinement of diffraction pattern at low temperature (-2.63$^{\circ}C$). The position is 0.9103${\AA}$ from the O sub(4) location and located at atomic coordinates (x/a=0.138, y/b=0.5, z/c=0.305) with the OH vector almost normal to plane (001). According to the increase of the temperature, $\alpha$* (tetrahedral rotation angle), $t_{oct}$ (octahedral sheet thickness), mean distance increase except 90$0^{\circ}C$ data. But the trend is less clearly relative to unit cell dimension expansion because the expansion is dominant to the interlayer. Also, ${\Psi}$ (octahedral flattening angle) shows no trends as increasing temperature and it may be because the octahedron (M1, M2) is substituted by Mg and Fe.

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A Study on Lateral Flow in Soft Grounds under Embankments for Road Constructions (도로 성토로 인한 연약지반의 측방유동에 관한 연구)

  • Kim, Junghoon;Hong, Wonpyo;Lee, Choongmin;Lee, Junwoo
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.9
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    • pp.17-29
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    • 2012
  • To investigate the characteristics of shear strength and soil deformation in soft grounds, in which various vertical drains were placed, two hundreds field monitoring data of embankments performed in thirteen road construction sites at west and south coastal areas of the Korean Peninsula were collected. At first, the relationship between settlement and lateral displacement was investigated into three stages, in which embankment construction works were divided into initial filling stage, final filling stage and stage after complete filling. And then, the relationship of surcharge pressures and embankment heights with undrained shear strength of soft grounds were investigated. The investigation on settlement and lateral displacement illustrated that the increment of lateral flow to the increment of settlement was low during initial filling stage, but increased gradually with filling and showed largest during final filling stage. After complete filling, the lateral displacement was converged, even though the settlement was increased continuously. Therefore, most of lateral flow was occurred during embankment filling. The ratio of the lateral displacement increment to the settlement increment was 20% for initial filling stage, which coincided with the one presented by Tavenas et al.(1979), but became 50% for final filling stage, which was half of the one presented by Tavenas et al.(1979). However, the ratio reduced to 1% to 9%, which was quite lower than the one presented by Tavenas et al.(1979). Shear deformations, even shear failures, were predicted in soft grounds under initial undrained shear strength, since the design heights of embankments were higher than the yield height in all the sites. However, embankment construction would be possible since the yield height became higher than the design height due to improvement of shear strength of soft grounds with application of the vertical drains. In order to perform safely embankments for road constructions, the embankment loads should be designed not to be exceed 5.14 times the initial undrained shear strength of soft grounds and to be less than 3.0 times the undrained shear strength improved with application of vertical drains in soft grounds.

Foundation Methods for the Soft Ground Reinforcement of Lightweight Greenhouse on Reclaimed Land: A review (간척지 온실 기초 연약지반 보강 방법에 대한 고찰)

  • Lee, Haksung;Kang, Bang Hun;Lee, Su Hwan
    • Journal of Bio-Environment Control
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    • v.29 no.4
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    • pp.440-447
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    • 2020
  • The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

A Study on Shape Optimization of Plane Truss Structures (평면(平面) 트러스 구조물(構造物)의 형상최적화(形狀最適化)에 관한 구연(究研))

  • Lee, Gyu won;Byun, Keun Joo;Hwang, Hak Joo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.5 no.3
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    • pp.49-59
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    • 1985
  • Formulation of the geometric optimization for truss structures based on the elasticity theory turn out to be the nonlinear programming problem which has to deal with the Cross sectional area of the member and the coordinates of its nodes simultaneously. A few techniques have been proposed and adopted for the analysis of this nonlinear programming problem for the time being. These techniques, however, bear some limitations on truss shapes loading conditions and design criteria for the practical application to real structures. A generalized algorithm for the geometric optimization of the truss structures which can eliminate the above mentioned limitations, is developed in this study. The algorithm developed utilizes the two-phases technique. In the first phase, the cross sectional area of the truss member is optimized by transforming the nonlinear problem into SUMT, and solving SUMT utilizing the modified Newton-Raphson method. In the second phase, the geometric shape is optimized utilizing the unidirctional search technique of the Rosenbrock method which make it possible to minimize only the objective function. The algorithm developed in this study is numerically tested for several truss structures with various shapes, loading conditions and design criteria, and compared with the results of the other algorithms to examme its applicability and stability. The numerical comparisons show that the two-phases algorithm developed in this study is safely applicable to any design criteria, and the convergency rate is very fast and stable compared with other iteration methods for the geometric optimization of truss structures.

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Functional Properties of Walnut in Cosmetics (호두의 화장품 기능성)

  • Kim, Mee-Kyung;Kim, Jin-Sung;Jo, Bun-Sung;Kim, Jeung-Hoan;Lee, In-Cheol;Lee, Myung-Sup;Cho, Young-Je
    • Journal of Life Science
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    • v.21 no.6
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    • pp.858-864
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    • 2011
  • The phenolic compounds of walnut extracts by various solvents were shown to be 24.3 mg/g in hot water, 34.4 mg/g in ethanol, 32.5 mg/g in methanol and 15.1 mg/g in acetone. In a comparison of phenolic compounds from hot water and different concentrations of ethanol, which are harmless, 60% ethanol extract and hot water extract were 34.7 mg/g, 24.6 mg/g. The electron donating ability (EDA) of walnut extracts in hot water and 60% ethanol were 78.1% and 80.6%. According to ABTS radical cation decolorization for antioxidant activity, hot water and 60% ethanol extract showed high antioxidant activities of 98.1% and 98.3%. Antioxidant protection factor (PF) were $1.1{\pm}0.2$ PF and $1.1{\pm}0.4$ PF in hot water and 60% ethanol extract. In TBARs inhibitory activity, each extract showed high antioxidant activities at 60% and 75%. Anti-inflammation effects of walnut extract were tested, and inhibition of NO was 50% in 100 ${\mu}g/ml$ phenolics. Inhibitory activity against iNOS and COX-2 were shown, through Western blot, to be 10% in 100 ${\mu}g/ml$ phenolics. Tyrosine inhibitory activity of 60% ethanol extract was 43%, and astringent effect of 60% ethanol extract was 55%. These results suggest that walnut extracts are suitable for functional cosmetics requiring skin-whitening and anti-wrinkle activity.

Evaluating the Appropriateness of the Forest Program in the Special Account for Balanced National Development - With a Focus on the Recognition of Local Government Officials in Forest sector - (국가균형발전특별회계(國家均衡發展特別會計) 대상(對象) 산림사업(山林事業)의 적정성(適正性) 평가(評價) - 지방자치단체 산림공무원의 인식을 중심으로 -)

  • Bae, Jae-soo;Park, Sang-mi;Song, Young-gun;Park, Keong-seok;Kim, Se-bin;Kwak, Kyung-ho
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.680-689
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    • 2006
  • Introduction of the Special Account for Balanced National Development (SABND) which was represented top-down in 2005 have previous national budget distribution system between central and local government change. A local autonomous entities can choose freely the favorite programs within the total programs in SABND so they can use limited budget efficiently, After induction of this system, budget of the Forest Programs in SABND in 2006 compare to last year has increased by 24.5 percent. That is three times higher than the average rate of total SABND budget, 8.1 percent. This study surveyed propriety of the Forest Programs and hereafter their budget prospect with local government officials in forest sector, 68.7 percent of the respondents recognized that the inclusion of the Forest Programs in SABND is proper. The most preferred Forest Programs are making Urban Forests and their Management and making Facilities for Forest Recreation. And the most non-preferred Forest Programs are complementing the Lumberyard Facility of the Forestry Association, making the Exhibition of Wood Products and making the Base for the Seedling Production. When Forest Programs are adjusted in the future, these programs above mentioned should be exempted from the SABND. because the non-preferred programs as well as the small budget programs On the prospect of the future budget, 81.1 percent of the local government officials in forest sector answered that it will be the same with the current or increasing, In the short term, the budget of the Forest Program in SABND is expected to increase.