• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.226-234
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• 2004

In this study experiments are conducted with a mid-layer type structure. This structure can operate not only at water surface but also in water. Six degrees of freedom oscillations of the structure and mooring force were measured by model experiments. From these experiments, it was shown that the lattice model has two peaks in the surge response curve and the oscillation amplitude and mooring forces increase according to the distance of separation between water level and upper deck.

• Korean Journal of Computational Design and Engineering
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• v.7 no.3
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• pp.148-156
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• 2002

Most Rapid Prototyping (RP) processes adopt a solid Computer Aided Design (CAD) model, which will be sliced into thin layers of constant thickness in the building direction. Each cross-sectional layer is successively deposited and, simultaneously, bonded onto the previous layer; and eventually the stacked layers from a physical part of the model. A new RP process, the transfer-type Variable Lamination Manufacturing process using expandable polystyrene foam sheet (VLM-ST), has been developed to reduce building time and to improve the surface finish of parts with the thick layers and a sloping surface. This paper describes the generation of Unit Shape Layer (USL), the cutting path data of the linen. hotwire cutter for the VLM-ST process. USL is a three-dimensional layer with a thickness of more than 1 mm and a side slope, and it is the basic unit of cutting and building in the VLM-ST process. USL includes data such as layer thickness, positional coordinates, side angles of each layer, hotwire cutting speed, the heat input to the hotwire, and reference shape. The procedure of generating USL is as follows: (1)Generation of the mid-slice from the CAD model, (2)Conversion of the mid-slice into a simply connected domain, (3)Generation to the reference shape for the mid-slice, (4)Calculation of the rotation angle of the hotwire of the cutting system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.3
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• pp.185-191
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• 1990

A study on the characteristics of phosphorus sedimentation in Nakdong Estuary Barrage was conducted in June and July, 1989. Cylindric type sediment trap was designed for collecting of downward material. Downward flux and settling velocity of downward material were $296g/m^2/d$, 1.25m/hr in mid-layer and $955g/m^2/d$, 3.31m/hr in bottom-layer, respectively Downward flux and settling velocity of phosphorus were $0.64g/m^2/d$, 0.85m/hr in mid-layer and $1.97g/m^2/d$, 1.89m/hr in bottom-layer, respectively. Fractional composition of organic phophorus in downward material was $51.9\%$ in mid-layer water and $48.3\%$ in bottom-layer water. According to the result of this study, sedimentation of phosphorus plays an important role as a sinking effect in Nakdong Estuary Barrage.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.127-127
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• 2010

Owing to many advantages on indirect intersubband absorption from the hole miniband to the electron miniband based on the type-II band alignment in InAs/GaSb strained-layer superlattice (SLS), InAs/GaSb SLS infrared photodetector (SLIP) has emerged as a promising system to realize high-detectivity quantum photodetector operating up to room temperature in the spectral range of mid-infrared (MIR) to far-infrared (FIR). In particular, n-barrier-n (n-B-n) structure designed for blocking the majority-carrier dark current makes it possible for MIR/FIR dual-band SLIP whose photoresponse (PR) band can be exclusively selected by the bias polarity. In this study, we present the MIR and FIR photoresponse (PR) mechanism identified by dual-band PR spectra and photoluminescence (PL) profiles taken from InAs/GaSb SLIP. In the MIR/FIR PR spectra measured by changing bias polarity, each spectrum individually shows a series of distinctive peaks related to the transitions from the hole subbands to the conduction one. The PR mechanism at each polarity is discussed in terms of diffusion current, and a superposition of MIR-PR in the FIR-PR spectrum is explained by tunnelling of electrons activated in MIR-SLS. The effective FIR-PR spectrum decomposed into three curves for HH1, LH1, and HH2 has revealed the edge energies of 120, 170, and 220 meV, respectively, and the temperature variation of the MIR-PR edge energies shows that the temperature behavior of the SLS systems can be approximately expressed by the Varshni empirical equation.

• Journal of Fisheries and Marine Sciences Education
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• v.13 no.1
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• pp.87-98
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• 2001

1. The bottom mean size of the research area had been showed 86.8% in, 13.2% in mud artificial sector, but and 82.4% in mud at comparative sector. 2. The water temperature had been showed $11.2{\sim}12^{\circ}C$ in surface, $10.9^{\circ}C$ in mid layer, $10.6{\sim}10.8^{\circ}C$ in lower layer. also, The salinity had been showed $31.85{\sim}31.95_{psu}$ in surface, $31.82{\sim}31.97_{psu}$ in mid layer, $31.85{\sim}31.97_{psu}$ at lower layer. The transparency was showed 3.6~5.6m. 3. The conservation condition of reefs was partially grooved and buried the lower part of reefs established '95~'96years but was good condition generaly. 4. The attached fauna has been appeared fisheres botanical specise 6, fisheries animate species 5. 5. The lure of fisheres has been appeared 17 species in reefs sector, 10 species in comparative sector(natural fishing ground). 6. The catchs of C.P.U.E by fishery was catched 2.2~3.3 times in reefs sector than the natural fishing ground. but the individuals was much catched in traps. The jumbo type reefs gill netter were much catched in square artificial reefs. The weight of fishery was much captured in jumbo type reefs.

• Journal of the Korean Society of Costume
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• v.64 no.2
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• pp.17-34
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• 2014

This is a theoretical and empirical study on Kasaya, the Buddhist monk's robe, which is one of the traditional Korean costumes that has kept it original form, as well as it being the most symbolic ritual costume in Buddhism. The purpose of the study is to see the different types of Kasaya, and the transitions it has gone through since Mid Joseon Dynasty. The analysis was performed after categorizing Kasaya in the following manner: layers, the way to wear, symbolism in construction, sewing, etc. Having a variety of Ilwolguangcheop(日月光貼) is a feature of Korean Red Kasaya. In the beginning, Its shape was very similar to shape of Hyungbae(胸背), and this was a royal gift and had the same meaning as an official uniform for a Buddhist monk. So designs of the Cheop(貼) could have been transformed from those of Hyungbae with a Buddhist twist. The conclusion of the study is as follows: Double layered Kasaya shows its transition from double layer to single layer. The fastening ornaments have been simplified in all materials from Yeongja(纓子). The latch type and three-paired Yeongja type transformed into hook type and one-paired Yeongja type. Color is the most common feature above all, and it is mainly in red. The form of Korean Kasaya has a significant relation with development of Buddhism. The integration of the Zen sect would have influenced the integration of Kasaya, which shows diversity throughout the period.

• Journal of Sensor Science and Technology
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• v.23 no.3
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• pp.170-172
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• 2014

$CO_2$ sensor was used only one solid electrolyte in many cases. To improve the sensing characteristics of $CO_2$ sensors, solid electrolyte $CO_2$ sensor has been developed by bi-electrolyte type sensor using Na-Beta-alumina and YSZ. However, in many further studies, bi-electrolyte type sensor was made by pellet pressed by press machine and additional treatment for formation of interface. In the aspect of mass production, using thick film and additional treatment is not suitable. In this study, $CO_2$ sensor was fabricated by bi-electrolyte structure which was made by an NBA paste layer deposited on YSZ pellet and fired at $1650^{\circ}C$ for 2 hour. The formation of stable interface between YSZ and NBA were confirmed by SEM image. When the type IV electrochemical cell arrangement represented by $CO_2,O_2,Pt{\mid}Li_2CO_3-CaCO_3{\parallel}NBA{\parallel}YSZ{\mid}O_2,Pt$ is used to measure the $CO_2$ concentration in air. This sensor EMF should depend only on the concentration of $CO_2$ by logarithmic. Also, sensor shows $P_{CO_2}$ and EMF relationship like nerstian reaction at a temperature of $450^{\circ}C$.

• Journal of the Korean earth science society
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• v.40 no.1
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• pp.24-36
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• 2019

In the mid-eastern Yellow Sea, glacio-eustatic sea-level fluctuations and a regional tectonic subsidence have combined to represent an aggradational stacking pattern of sedimentary units during late Pleistocene-Holocene. The accumulated sediments are divisible into two-type units of Type-A and Type-B in high-resolution air-gun seismic profiles and the deep-drilled core of YSDP-105. Type-A unit largely comprises clast-rich coarse-grained sediments of non-marine to paralic origin, whereas Type-B unit consists mostly of tidal fine-grained sediments. Based on a bottom model of the sedimentary units, this study suggested a geoacoustic model of long-coring bottom layers at the YSDP-105 drilling site of the mid-eastern Yellow Sea. The geoacoustic model of 64-m depth below the seafloor with four-layer geoacoustic units was reconstructed in continental shelf strata at 45 m in water depth. For actual modeling, the geoacoustic property values of the models were compensated to in situ depth values below the seafloor using the Hamilton modeling method. We suggest that the geoacoustic model will be used for geoacoustic and underwater acoustic experiments of mid- and low-frequency reflecting on the deep bottom layers in the mid-eastern Yellow Sea.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.1
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• pp.25-30
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• 2020

Oxide (SiO₂)/Metal(Ag)/Oxide(SiO₂, ITO, ZnO) multilayer films were fabricated using a magnetron sputtering technique at room temperature on Si (p-type, 100) and a glass substrate. The electrical and optical properties of the asymmetric multilayer films depended on the thickness of the mid-layer film and the type of oxide in the bottom layer. As the metal layer becomes thicker, the sheet resistance decreases. However, the transmittance decreases when the metal layer exceeds a threshold thickness of approximately 10~12 nm. In addition, the sheet resistance and transmittance change according to the type of oxide in the bottom layer. If the oxide has a large resistivity, the overall sheet resistance increases. In addition, the anti-reflection effect changes according to the refractive index of the oxide material. The optical and electrical properties of multilayer films were investigated using an ultraviolet visible (UV-Vis) spectrophotometer and a 4-point probe, respectively. The optimum structure is SiO₂ (30 nm)/Ag (10 nm)/ZnO (30 nm) multilayer, with the highest FOM value of 7.7×10^-3 Ω^-1.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.37-49
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• 2015

The goal of this research is to examine air temperature changes according to tree type, plantation type, roadside green area structure, and green volume of street green area within a city. The plantation type that could be analyzed for comparison by tree type with over 3 species was 1 rows of tree+shrubs. The results of analysis of average air temperature difference between pedestrian and car streets vis-a-vis 1 row of tree+shrub in high air temperature areas were: Pinus densiflora, $1.35^{\circ}C$; Zelkova serrata, $1.84^{\circ}C$; Ginkgo biloba, $2.00^{\circ}C$; Platanus occidentalis, $2.57^{\circ}C$. This standard large wide canopy species was analyzed by the roadside to provide shade to have a significant impact on air temperature reduction. In terms of analysis of the relationship between plantation type of roadside trees and air temperature, the average air temperature difference for 1 row of tree type was $1.80^{\circ}C$; for 2 rows of trees it was $2.15^{\circ}C$. In terms of analysis of the relationship between the roadside green area structure and air temperature, for tree type, average air temperature $1.94^{\circ}C$: for tree+shrub type, average air temperature $2.49^{\circ}C$; for tree+mid-size tree+shrub type, average air temperature $2.57^{\circ}C$. That is, air temperature reduction was more effective in a multi-layer structure than a single layer structure. In the relationship analysis of green volume and air temperature reduction, the air temperature reduction effect was enlarged as there was a large amount of green volume. There was a relationship with the green volume of the road, the size of the tree and number of tree layers and a multi-layer structured form of planting. The canopy volume was large and there were a great number of rows of the tree layer and the plantation type of multi-layer structure, which is what is meant through a relationship with the green volume along the roadside. Green composition standards for air temperature reduction effects and functional improvement were proposed based on the result. For a pedestrian street width of 3m or less in the field being ideal, deciduous broadleaf trees in which the canopy volume is small and the structure of the tree+shrub type through the greatest 1m green bend were proposed. For a pedestrian street width of over 3m, deciduous broadleaf trees in which the canopy volume is large and is multi-layer planted with green bend over 1m, tree+mid-size tree+shrub type was proposed.