• Title/Summary/Keyword: 중앙축

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Morphological Adaptation of Zostera marina L. to Ocean Currents in Korea (한국산 거머리말(Zostera marina L.)의 해류에 대한 형태적 적응)

  • Lim, Dong-Ok;Yun, Jang-Tak;Han, Kyung-Shik
    • Korean Journal of Environment and Ecology
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    • v.23 no.5
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    • pp.431-438
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    • 2009
  • The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.

The study on the structure of the Lee Je-ma's viewpoint of Morpho-Image (이제마(李濟馬) 형상관(形象觀)의 구조적(構造的) 고찰(考察))

  • Lee, Jun-hee;Koh, Byung-hee;Song, Il-byung
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.1
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    • pp.41-61
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    • 1999
  • The purpose of this article is to investigate Lee Je-rna'os viewpoint of Morpho-Image. In the first place, I will define the viewpoint of Morpho-Image as the the structure of recognition and study it through bibliographic study on Lee Je-ma's work. The conclusions summarized as follows; 1. The structure of recognition, represented in "Gyukchigo(格致藁)" "Dongyi Soose Bowon Sasang Chobonkyon(東醫壽世保元四象草本卷)", is based on Taigi(太極), Liangyi(兩儀), Sasang(四象). There are the mind of Taigi(太極), the mind of Liangyi(兩儀) separated from Taigi(太極), the mind of Sasang(四象) separated from Liangyi(兩儀). The mind of Taigi(太極) is the mind of center, the mind of Liangyi(兩儀) is the mind of the mind and body(or the wisdom and action). Two axis, the mind(or wisdom) and the body(or action), cross and make Sasang(四象), affair-mind-body-object which classifies all affairs and objects of humans, society, and the universe as four types. 2. Lee Je-ma summarized everything in view of Sasang(四象), Sasang(四象) in view of Liangyi(兩儀), Liangyi(兩儀) in view of Taigi(太極). 3. The procedure of recognition above is described in , , . Such is transformed in terms of human body and described in .

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Verification of Indicator Rotation Correction Function of a Treatment Planning Program for Stereotactic Radiosurgery (방사선수술치료계획 프로그램의 지시자 회전 오차 교정 기능 점검)

  • Chung, Hyun-Tai;Lee, Re-Na
    • Journal of Radiation Protection and Research
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    • v.33 no.2
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    • pp.47-51
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    • 2008
  • Objective: This study analyzed errors due to rotation or tilt of the magnetic resonance (MR) imaging indicator during image acquisition for a stereotactic radiosurgery. The error correction procedure of a commercially available stereotactic neurosurgery treatment planning program has been verified. Materials and Methods: Software virtual phantoms were built with stereotactic images generated by a commercial programming language, Interactive Data Language (version 5.5). The thickness of an image slice was 0.5 mm, pixel size was $0.5{\times}0.5mm$, field of view was 256 mm, and image resolution was $512{\times}512$. The images were generated under the DICOM 3.0 standard in order to be used with Leksell GammaPlan$^{(R)}$. For the verification of the rotation error correction function of Leksell GammaPlan$^{(R)}$, 45 measurement points were arranged in five axial planes. On each axial plane, there were nine measurement points along a square of length 100 mm. The center of the square was located on the z-axis and a measurement point was on the z-axis, too. Five axial planes were placed at z=-50.0, -30.0, 0.0, 30.0, 50.0 mm, respectively. The virtual phantom was rotated by $3^{\circ}$ around one of x, y, and z-axis. It was also rotated by $3^{\circ}$ around two axes of x, y, and z-axis, and rotated by $3^{\circ}$ along all three axes. The errors in the position of rotated measurement points were measured with Leksell GammaPlan$^{(R)}$ and the correction function was verified. Results: The image registration errors of the virtual phantom images was $0.1{\pm}0.1mm$ and it was within the requirement of stereotactic images. The maximum theoretical errors in position of measurement points were 2.6 mm for a rotation around one axis, 3.7 mm for a rotation around two axes, and 4.5 mm for a rotation around three axes. The measured errors in position was $0.1{\pm}0.1mm$ for a rotation around single axis, $0.2{\pm}0.2mm$ for double and triple axes. These small errors verified that the rotation error correction function of Leksell GammaPlan$^{(R)}$ is working fine. Conclusion: A virtual phantom was built to verify software functions of stereotactic neurosurgery treatment planning program. The error correction function of a commercial treatment planning program worked within nominal error range. The virtual phantom of this study can be applied in many other fields to verify various functions of treatment planning programs.

Study on Changes of the Regional Innovation Paradigm & the Structure of Regional Innovation System - Focused on Removal of Public Organization - (지역혁신 패러다임과 지역혁신체계의 변화에 관한 연구 - 공공기관 지역이전을 중심으로한 변화 -)

  • Sul, Gee-Hwan;Ryu, Seuc-Ho;Kyung, Byung-Pyo;Lee, Dong-Lyeor
    • Journal of Digital Convergence
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    • v.13 no.11
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    • pp.373-381
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    • 2015
  • The public organization in the metropolitan area moved to regional province by Regional Innovation Policy in South Korea. This policy was settled to solve the problem of concentration in metropolitan areas and underdeveloped regions caused by industrial development strategy for 40 years from 1960s till 2000s. Government decided the plan under the judgement that moving public organization (or institutions) is one of National Innovation Strategy for balanced development. Furthermore, Central organizations/institutions were to be the subject of regional innovation by leading the regional innovation and building a new regional innovation system. The Purpose of this study is finding out the new direction of regional innovation paradigm and a new regional innovation system to be changed after previous public organization moving from metropolitan area to region province. And this study pointed up the problem between plan and process of Organization Removal, suggested the topics for success of New RIS, and prepared more details methods in future study.

Performance of Sudangrass, Sudangrass Hybrids and Sorghum-Sudangrass Hybrids for Forage Production V. Comparison of recommended cultivars of sorghum-sudangrass hybrids (수단그라스, 수단그라스잡종 및 수수-수단그라스잡종의 사초생산성 V. 수단그라스계 장려품종의 비교)

  • 김동암;김종림;권찬호;김원호;김종관
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.11 no.4
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    • pp.258-263
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    • 1991
  • There are ten NLCF's recommended sorghum-sudangrass hybrids(Sorghum bicolor (L.) Moench), but they have not been evaluated under same environmental conditions. Therefore, a field experiment was conducted to campare forage yield and quality of the NLCF's recommended cultivars of sorghum-sudangrass hybrids at the experimental forage field, College of Agriculture, SNU, Suweon over two years. Among the ten cultivars used, G83F and NC+855 were classified as early maturing cultivars. Pioneer 988 and Sordan 79 were more resistant to leaf blight than the other hybrids. Jumbo, Sordan 79 and SX-17 were susceptible to lodging. No significant differences in dry matter yield were found among the cultivars used, but the dry matter yields of Pioneer 988, TE-Haygrazer and G83F were slightly higher than the other hybrids in 1989 and those of NC+855 and Pioneer 988 were higher in 1990. There were no marked cultivar differences in CP, ADF, NDF and RFV at the first, second and third cuts in 1990, but the ADF, NDF and RFV of sorghum-sudangrass hybrids at the third cut showed more higher than those of the first and second cut forage. In conclusion, there are no forage yield differences among the ten NLCF's recommended sorghum-sudangrass hybrids.

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Heat Transfer in Bubble Columns with High Viscous and Low Surface Tension Media (고점성 낮은표면장력 매체 기포탑에서 열전달)

  • Kim, Wan Tae;Lim, Dae Ho;Kang, Yong
    • Korean Chemical Engineering Research
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    • v.52 no.4
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    • pp.516-521
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    • 2014
  • Axial and overall heat transfer coefficients were investigated in a bubble column with relatively high viscous and low surface tension media. Effects of superficial gas velocity (0.02~0.1 m/s), liquid viscosity ($0.1{\sim}0.3Pa{\cdot}s$) and surface tension ($66.1{\sim}72.9{\times}10^{-3}N/m$) on the local and overall heat transfer coefficients were examined. The heat transfer field was composed of the immersed heater and the bubble column; a vertical heater was installed at the center of the column coaxially. The heat transfer coefficient was determined by measuring the temperature differences continuously between the heater surface and the column which was bubbling in a given operating condition, with the knowledge of heat supply to the heater. The local heat transfer coefficient increased with increasing superficial gas velocity but decreased with increasing axial distance from the gas distributor and liquid surface tension. The overall heat transfer coefficient increased with increasing superficial gas velocity but decreased with increasing liquid viscosity or surface tension. The overall heat transfer coefficient was well correlated in terms of operating variables such as superficial gas velocity, liquid surface tension and liquid viscosity with a correlation coefficient of 0.91, and in terms of dimensionless groups such as Nusselt, Reynolds, Prandtl and Weber numbers with a correlation of 0.92; $$h=2502U^{0.236}_{G}{\mu}^{-0.250}_{L}{\sigma}^{-0.028}_L$$ $$Nu=325Re^{0.180}Pr^{-0.067}We^{0.028}$$.

Anatomy of the Korean mistletoe and their haustorial features in host plants (한국산 겨우살이과 식물의 형태와 기주별 흡기 특징)

  • Choi, Kyung;Park, Kwang-Woo;Kim, Hyuk-Jin;Lee, Jae-Dong;Koo, Jachoon;Whang, Sung-Soo
    • Korean Journal of Plant Taxonomy
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    • v.39 no.1
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    • pp.4-11
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    • 2009
  • Anatomical features of both leaves and stems of the four mistletoes in Korea (Viscum album var. coloratum, Korthalsella japonica, Loranthus yadoriki, L. tanaka) and of their secondary haustorial structure within several host plants were investigated. Among the four mistletoes, there were diagnostic characters of the anatomy of leaves and stems which enabled us to distinguish the four taxa. Leaves were observed to have three distinct characters including unifacial or bifacial leaves, the number of vascular bundles in the midveins, and the level of development of sclerenchyma cells. There were four diagnostic characters of stems: overall morphology of stems in transverse view, degree of cuticle development, arrangement of vascular bundles, and features of the sclerenchyma and pith. In order to determine secondary haustorial traits, the research focused on the seven host plants of L. yadoriki and on the five host plants of K. japonica. The following features were found to be important: presence or absence of an aerial runner root, the shape of the haustorial strand and flange, the degree of penetration into host tissues, and their development of shaft in transverse view, the development both of secondary haustorial cells and short tracheid in hyphae. Korthalsella japonica and L. yadorki were clearly distinguished by these characters. The secondary haustorial forms in each host were somewhat different, due to varying degrees of development in the strength of the host plants' wood. However, qualitative characters like the final position of the secondary haustorial penetration into host tissues and the development of short tracheid cells were not only affected by the degree of development of the host plants, but also useful for the systematic study.

A Study on Seawater Flow Characteristics inside the Shrouds used in Tidal Current Generation Systems for Various Geometric Angles under Constant Tidal Current Velocity (조류발전 시스템용 쉬라우드의 형상각도별 일정 조류속도장 내 해수유동 특성연구)

  • Kim, Jong-Won;Lee, Sang-Ho
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.2
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    • pp.77-83
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    • 2012
  • Numerical analyses through Computational Fluid Dynamics have been performed to investigate the seawater flow field characteristics for various shrouds used in horizontal axis tidal current turbine systems. Seawater flow characteristics are largely influenced under constant tidal current velocity by the shroud geometry and there is considerable difference in fluid velocity distributions around the shrouds. Especially the location and magnitude of maximum seawater flow velocity directly affect turbine performance for power generation. For the cylinder-diffuser type shroud system whose cylinder and diffuser parts have the same length accelerated flow region is formed in the overall cylinder part while maximum velocity in the nozzle-diffuser type whose nozzle and diffuser parts have the same length with symmetry, locally appears near the minimum sectional area. In case of cylinder-diffuser type shroud fluid velocity increases rather high compared with current velocity. And fluid velocity at the centerline gradually increases from the entrance, and then decreases rapidly after reaching a peak close to the middle of the cylinder part unlike the nozzle-diffuser while there is not much variation near the rear of the shroud. These results of the seawater flow characteristics with various shroud geometries can be applied to optimal design for the development of efficient tidal current power generation systems.

The Study of Hydrothermal Vent and Ocean Crustal Structure of Northeastern Lau Basin Using Deep-tow and Surface-tow Magnetic Data (심해 및 표층 지자기 자료를 이용한 라우분지 북동부의 열수 분출구 및 해저 지각 구조 연구)

  • Kwak, Joon-Young;Won, Joong-Sun;Park, Chan-Hong;Kim, Chang-Hwan;Ko, Young-Tak
    • Economic and Environmental Geology
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    • v.41 no.1
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    • pp.81-92
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    • 2008
  • Fonualei Rift and Spreading Center(FRSC) and Mangatolu Triple function(MTJ) caldera are located in northeastern part of Lau basin which is the active back-arc basin. Deep-tow and surface-tow magnetic surveys are carried out in FRSC. In deep-tow magnetic survey, to compensate for influence of uneven distance between bathymetry and sensor height, magnetic anomaly is continued upward to a level plane by using the Guspi method. We calculate crustal magnetization using Parker and Huestis's inversion algorithm, and try to find the hydrothermal vent and understand the structure of ocean floor crust. The result of deep-tow magnetic survey at FRSC showed that Central Anomaly Magnetization High(CAMH) recorded the max value of 4.5 A/m which is associated with active ridge. The direction of SSW-NNE corresponds with the direction of the principal spreading ridge in Lau basin. The low crustal magnetizaton$(174^{\circ}35.1'W,\;16^{\circ}38.4'S)$ of -4.0 A/m is supposed to correlate with submarine hydrothermal vent. Surface-tow magnetic data were collected in MTJ caldera$(174^{\circ}00'W,\;15^{\circ}20'S)$. The prevailing SSW-NNE direction of collapsing walls and the presence of CAMH at the center of caldera strongly indicate the existence of active spreading ridge in ancient times.

Study of Wooden Chukmok and Chukdu Used for East Asian Mounting (동양 장황에 사용된 축목과 축두에 관한 연구)

  • Jang, Yeonhee
    • Conservation Science in Museum
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    • v.19
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    • pp.53-68
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    • 2018
  • Hanging scrolls and handscrolls are common mounting for East Asian painting and calligraphy in which wooden Chukmok with Chukdu of various materials are attached either at the top and bottom or at each side of a work. Hanging scroll paintings or calligraphy can be hung for appreciation and rolled up for preservation. The Chukmok and Chukdu of a hanging scroll were made from different materials and were known by distinct names in Korea, China, and Japan. In Korea, the wooden Chukmok were called sanghachukhoengmok(上下軸橫木), which means horizontal wooden bars for the top and bottom axes. The wooden Chukdu were called Chukdu(軸頭), meaning the head of an axis. These Chukmok and Chukdu were made of Korean red pine, nut pine, or shiny xylosma. In China, the rod was called zhougan(軸杆) and zhoutou(軸頭), and they were made of Japanese cedar, sappan wood, or red sandalwood. In Japan, the top rod was called hassou(八双; 八裝) and the bottom jikugi(軸木), and they were made of Japanese cedar, red sandalwood, or crystal. In Korean hanging scrolls, the cross section of a Chukdu is either flat or round, and it can be either patterned or patternless. The designs include concentric circles, two circles, and three circles. Among the portraits of meritorious subjects analyzed in this study, three examples feature concentric circles on Chukdu with a flat cross section, which coincides with most of the king's instructions housed at the Jangseogak Archives. This suggests that flat Chukdu with a concentric circle pattern were used for binding most of the paintings of meritorious subjects commissioned by the royal court.