• Horticultural Science & Technology
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• v.29 no.6
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• pp.617-622
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• 2011

The study was conducted to determine the efficiency in producing spontaneous polyploids in some mandarin hybrids with different seed embryony. Seed formation by open pollination, frequency of spontaneous polyploids, and plant growth characteristics were evaluated in four mandarin hybrids with polyembryony such as 'Amakusa', 'Haruka', 'Hayaka', and 'Seminole' and two with monoembryony such as 'Benibae' and 'Harehime'. The mean number of the developed seeds per fruit was 10.0 and frequency of small seeds was 25.1%. Polyploids were selected from plants germinated in vitro by a flow cytometry and confirmed by chromosome analysis. One triploid was produced from 'Harehime', one tetraploid, 'Amakusa', and one tetrapoid, 'Benibae'. There were little differences in leaf shape, thickness, petiole length, and internode length between diploids and polyploids such as tri- or tetraploid. However, polyploids had larger stomata and lower density of stomata in abaxial epidermis than diploids. SPAS indicating chlorophyll content and photosynthetic rate were significantly affected by ploidy level. The results indicated that spontaneous polyploids might be produced by open pollination in some mandarin hybrids and monoembryony had higher frequency in polyploid occurrence than polyembryony.

• Ocean and Polar Research
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• v.24 no.4
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• pp.345-357
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• 2002

Ecological characteristics on habitats and morphological features of the seagrass Zostera caulescens Miki in Korea were examined. The biogeographical distribution of Z. caulescens was confirmed in the south coast of the Korea. Zostera caulescens usually inhabits at the inner bay, where is sheltered from wave action and 3.0 to 6.5 m deep. The sediment in habitats is composed of very fine muddy sand or sandy mud. In morphology, Z. caulescens is easily distinguished from other species of the genus by the formation of vegetative canopy on the top of reproductive stems. The number of longitudinal ribs in testa was 24 revealed by scanning electron microscope (SEM) while the number of ribs in Z. marina has been often reported to be 16-20. Purplish anthocyanin spots were displayed on the surface when the testa was removed. We found that the size and shape of leaf epidermal cells in Z. caulescens were very different from those of Z. marina when the leaf cuticles were removed by maceration which could be useful characters for identifying Zostera species. The leaf of Z. caulescens displays two different casts of color when the fresh plant is closely observed. The margins of leaves appear brighter than the center of leaves due to the thickening by the development of paralleled venation in the middle of leaves. The comparison of two populations of Z. caulescens in Korea showed that they were considerably different in their shoot density and biomass. The shoot density and biomass at Gabae population was $367.3 m^{-2}\;and\;725.7g$ dry wt $m^P{-2}$ respectively, while those at Jukrim population were $112.5m^{-2}\;and\;392.0g\;dry\;wt\;m^{-2}$, respectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.4
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• pp.343-353
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• 2017

Processing and equipment were tailored for engineering scale fabrication of $UO_2$ porous pellets, a feed material for the electrolytic reduction process in the PRIDE (PyRoprocessing Integrated DEmonstration) facility at KAERI (Korea Atomic Energy Research Institute). The starting materials, $UO_2$ powder and pre-milled surrogate oxide powders, were proportioned to simulate the chemical composition of spent fuel (so-called Simfuel). The Simfuel powders were homogenized by mixing, compacted into a pellet shape, and finally heat treated using a tumbling mixer, rotary press, and sintering furnace. After sintering at $1450^{\circ}C$ for 24 h in $4%\;H_2-Ar$, the average bulk density of the $UO_2$ Simfuel pellets was $6.89g{\cdot}cm^{-3}$, which meets the standard of the following electrolytic reduction process. In addition, the results of a microstructural analysis demonstrated that the sintered Simfuel $UO_2$ porous pellets accurately simulate the properties of spent fuel in terms of the formation of second phases. These results provide essential information for the massive fabrication of $UO_2$ porous pellets for engineering scale pyroprocessing research.

• Journal of Nutrition and Health
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• v.31 no.9
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• pp.1446-1456
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• 1998

Bones are important parts in sustaining the shape of the body, but they are also metabolic organs which undergo bone remodeling by constant bone resorption and formation. Osteoporosis, the typical metabolic bone disease, is characterized by a reduction in bone mineral density (BMD). Women more than men are at risk fir osteoporosis-related fractures, especially in the lumbar spine, wrist, and hip region. Risk of fracture depends on one's BMD, which open determined by the peak bone mass value achieved at skeletal maturity and followed by subsequent age-and menopause-related bone loss. Genetic and environmental factors are known to play a key role in bone metabolism and diet is considered as one of the important environmental factors. The purpose of the present study was to assess the status of BMD and bone mineral content(BMC) to clarify the relationships between dietary intakes and the risk of osteoporosis in adult women in Taegu. Subjects were 130 healthy females in between 20 and 69 years of age. BMD and BMC of the lumbar spine(venebrae L2-4) of the subjects were measured by dual energy X-ray absorptiometry. The average age of the subjects was 47.4${\pm}$11.7 years old, the average weight was 57.2${\pm}$8.4kg, the average age of menarche was 16.6${\pm}$1.9 years old and the average age of menopause was 48.4${\pm}$5.3 years old. The nutrient intakes of the subjects measured by the convenient method were generally lower than the level of RDA. The result of nutrient intake assessed has shown that the average energy intake was 1701${\pm}$316kca1 which is 85.1% of the RDA and the average calcium intake was 485.4${\pm}$172.3mg which is 69.3% of the RDA. The intakes of protein, vitamin A, vitamin B$_1$, niacin were greater than the RDA, whereas the remaining nutrient intakes were lower than the RDA. The average BMD of the subjects was shown to be 1.06${\pm}$1.09g/$\textrm{cm}^2$. The highest BMD of 1.24${\pm}$0.14g/$\textrm{cm}^2$ was noticed in the subjects of 30s compared to 20s, 40s, 50s, 60s. The BMD values were compared by the relative body weight(R3W) of the menopause subjects, and it was found that the underweight group had significant lower BMB while the rest of the groups did not have any differences in BMD. The most strongly correlated nutrient with BMD among the menopause subjects appeared to be calcium. The women whose Ca intakes were higher than 500mg showed the significantly higher BMD than those with Ca intakes lower than 500mg. This study suggests that the most effective way to prevent osteoporosis and to reduce the incidences of fractures seems to be minimizing bone loss through the adequate intake of calcium as well as avoiding underweight, especially in menopausal women. (Korean J Nutrition 31(9) . 1446-1456, 1998)

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1081-1089
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• 2005

In order to examine the application feasibility of Orimulsion fuel in a commercial boiler using heavy fuel oil, a numerical and experimental research efforts have been made especially to figure out the fundamental combustion characteristics of this fuel in a small-scale boiler. One of the notable combustion features of Orimulsion fuel is the delayed appearance of flame location with the flame shape of rather broad distribution, which is found experimentally and confirmed by numerical calculation. This kind of flame characteristics is considered due to the high moisture content included inherently in the process of Orimulsion manufacture together with micro-explosion by the existence of fine water droplets. In order to investigate the effect on the combustion characteristics of Orimulsion, a series of parametric investigation have been made in terms of important design and operational variables such as injected amount of fuel, types of atomization fluid, and phonemenological radiation model employed in the calculation, etc. The delayed feature of peak flame can be alleviated by the adjustment of the flow rate of injected fuel and the generating features of CO, $SO_2$ and NO gases are also evaluated in the boiler. When the steam injection as atomizing fluid is used, the combustion process is stabilized with the reduced region of high flame temperature. In general, the calculation results are physically acceptable and consistent but some refinements of phenomenological models are necessary for the better resolution of pollutant formation. From the results of this small-scale Orimulsion boiler, it is believed that a number of useful information are obtained with the working computer program for the near future application of Orimulsion fuel to a conventional boiler.

• Journal of the Korean Vacuum Society
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• v.9 no.2
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• pp.99-101
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• 2000

The fabrication of the submicron size hole has been interesting due to the potential application of the near field optical sensor or liquid metal ion source. The 2 micron size dot array was photolithographically patterned. After formation of the V-groove shape by anisotropic KOH etching, dry oxidation at $1000^{\circ}C$ for 600 minutes was followed. In this procedure, the orientation dependent oxide growth was performed to have an etch-mask for dry etching. The reactive ion etching by the inductively coupled plasma (ICP) system was performed in order to etch ~90 nm $SiO_2$ layer at the bottom of the V-groove and to etch the Si at the bottom. The negative ion energy would enhance the anisotropic etching by the $Cl_2$ gas. After etching, the remaining thickness of the oxide on the Si(111) surface was measured to be ~130 nm by scanning electron microscopy. The etched Si aperture can be used for NSOM sensor.

• Journal of the Korean Vacuum Society
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• v.21 no.5
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• pp.233-241
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• 2012

We have deposited the bilayer consisted of the underlayer and the overlayer by using DC magnetron sputter on Single crystal MgO (001) substrate. This bilayer was fabricated at fixed annealing temperature and time. We have controlled agglomeration effect by changing of the bilayer thickness. Finally, we have made the self-organization and nano-structured film. In this processing, we have made nano-dot which consists of the underlayer and the overlayer, unlike the existing method called the agglomeration effect in the single layer. The underlayer has deposited using Ti, Cr and Co. And the overlayer has deposited with Ag. Through the analysis of Atomic force microscopy (AFM), the microstructure of underlayer is observed by AFM to confirm the formation of nano-dot. As the nano-dot through above processing, we have found that the nano-dot has the different shape. As a result, when we manufactured nano-dot through the agglomeration effect of bi-layer, the best matching material is Ti for underlayer. And also, we have found that MgO/Ti/Ag samples have been grown expitaxially toward the direction of MgO (001) by X-ray Diffraction analysis.

• The Journal of the Petrological Society of Korea
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• v.16 no.3
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• pp.162-179
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• 2007

Macheon Layered Intrusion (MLI) which intruded into Precambrian gneiss complex of the northern Jirisan area, southeastern part of Youngnam (or Sobaeksan) Massif, is a layered mafic-ultramafic complex of Triassic age (ca. 223 Ma). The MLI is divided into Layered Series and Laminated Series. Layered Series is subdivided into Central Zone (Lower Zone) consisting of olivine gabbros and Peripheral Zone (Middle or Upper Zone) consisting of hornblende gabbros based on the type of cumulus texture and the main mafic phase. The Central Zone of Layered Series comprises thinly laminated olivine gabbros and uniform or thickly laminated coarse olivine gabbros which consist of mela-gabbro, troctolite, leuco-troctolite, and anorthositic rocks. Laminated Series is also subdivided into quartz-bearing biotite-pyroxene gabbros and homblende diorite and both have variable amount of interstitial quartz and microcline. Laminated series display moderately to slightly developed igneous lamination which is defined by the planar alignment of lath-shape plagioclases. Chilled margin of quartz-bearing biotite-pyroxene gabbro with surrounding Precambrian gneisses insists shallower intrusion of more felsic cognate magma evolved in the deep a little later. Rocks of Layered Series have orthocumulus to adcumulus olivine, adcumulus to intercumulus plagioclase, and intercumulus to heteradcumulus pyroxene and hornblende. Magmatic modally grading, folding, and cross-lamination are not rarely occurred in thinly layered rocks. These textural characteristics define main mechanisms of the formation of layered and laminated structure in mafic-ultramafic rocks of Macheon Layered Intrusion are gravity settling and in-situ crystallization associated with slumping and density current.

• The Research Journal of the Costume Culture
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• v.13 no.6 s.59
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• pp.960-976
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• 2005

Classicism pursued beauty comprised of a perfect form, and beauty was perceived as a state of sufficiency. Accordingly, a completed and permanent beauty was sought after; as a result, a perfect and flawless form became the mainstream, and there was an effort to visualize the eternal proportional perfection. In classicism, forms were perfectly embodied with systematic inevitability and absolute inflexibility, by which an extremely clear aspect appeared. This study analyzes a classical construction paradigm in modern fashion according to the five categories: 'Harmony and order by numerical proportion', 'Clear form', 'Simplification of form and two-dimensional Seh-form', 'Completed contracture structure', and 'Pluralistic unification', and the respective formative characteristics are as follows. First, in terms of the formative aspect of modern fashion,'Harmony and order by numerical proportion' results from thorough observance of extreme and golden section (proportion of 5 :8) which was an aesthetic standard of beautiful body in classicism. Second, 'Clear form' appears in clothes as individual clearness of structural elements expressing each part of body, and shows a well-established form possible to be grasped with equal and clear contour line. Third,'Simplification of form and two-dimensional Seh-form' comes out as form composition, single line, single layer structure, two-dimensional form and arrangement of elements of clothes through the front viewpoint caused by 2D diagramming work while fashion-designing and producing. Also, it is seen that two-dimensional proportion which is composed of sections through various harmonious lines and sides according to the simple two-dimensional compatibility principle is accomplished. Fourth, 'Completed contracture structure' emerges as an expression of stationariness, in other words, fixation of an overall impression. This is a tendency that the overall form is grasped as a fixedly intact shape without a big change of the silhouette of clothes. Fifth, 'Pluralistic unification' means that it respectively emphasizes all the parts composing clothes by making them individually independent at the same time as each element is inclusively shown with the harmony of the overall silhouette of clothes and many other details. This study examined classical formative characteristics through a theoretical research on a formative paradigm revealing the classical style. Also, the significance of classical or rational value of art was illuminated by observing what characteristics a classical formation paradigm shows in modern fashion. As a result, classical characteristics in modern fashion prove that classicism is not a merely past construction style separated from the present but a construction paradigm deeply involved in our reason system.

• Geophysics and Geophysical Exploration
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• v.17 no.1
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• pp.28-33
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• 2014

We investigate the spatial distribution of highly conductive layer using the one-dimensional inversions of the new magnetotelluric (MT) measurements obtained at the mid-mountain (400 ~ 900 m in elevation) western area of Jeju Island and the previous MT data over Jeju Island, Korea. The conductive layer indicates the sedimentary layer comprised of Seoguipo Fomation and U Formation. There is a definite positive correlation between the top of conductive layer and the earth surface in elevation. On the contrary, the bottom of conductive layer has a negative correlation with the surface elevation. In other words, the conductive layer has a shape of convex lens, which is thickest in the central part. The basement beneath the conductive layer could be concave in the central part of Jeju Island. A kriging considering the correlation between the layer boundary and the surface elevation provides a reliable geoelectric structure model of Jeju Island. However, further studies, i.e. three-dimensional modeling and interpretation integrated with other geophysical or logging data, are required to reveal the possible presence of three-dimensional conductive body near the subsurface vent of Mt. Halla and the causes of the bias in the depths of layer estimated from MT and core log data.