• 한국농공학회논문집
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• 제61권4호
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• pp.33-42
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• 2019

In this study, the channel and floodplain widths are indirectly measured for three different watersheds using satellite images to reflect the shape of Korean channels in the Soil and Water Assessment Tool (SWAT) model. For measuring the channel and floodplain widths, multiple satellite images were referred to ensure the widest width of certain points. In the single channel, the widths at the multiple points were measured. Based on the measured data, the regression equations were derived to estimate the channel and floodplain widths according to watershed areas. Applying these developed equations, this study evaluated the effect of the change of channel and floodplain widths on the SWAT simulation by comparing to the measured streamflow data. The developed equations estimated larger channel width and smaller floodplain compared with those calculated in the current SWAT model. As shown in the results, there was no considerable changes in the predicted streamflow using the current and developed equations. However, the flow velocity and channel depth calculated from the developed equations were smaller than those of the current equations. The differences were caused by the effect of different channel geometries used for calculating the hydraulic characteristics. The channel geometries also affected the water quality simulation in channels because the hydraulic characteristics calculated by the channel geometries are directly related to the water quality simulation. Therefore, application of the river cross-sectional regression equation reflecting the domestic stream shape is necessary for accurate water quantity / quality and water ecosystem simulation using hydrological model.

• 한국해양공학회지
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• 제36권5호
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• pp.326-339
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• 2022

Recently, not only Korea but also the world has been suffering from problems related to coastal erosion. The hard defense method has been primarily used as a countermeasure against erosion. However, this method is expensive and has environmental implications. Hence, interest in other alternative methods, such as the eco-friendly vegetation method, is increasing. In this study, we aim to analyze the hydraulic characteristic of submerged rigid vegetation according to the cross-sectional change through a hydraulic experiment and numerical simulation. From the hydraulic experiment, the reflection coefficient, transmission coefficient, and energy dissipation coefficient were analyzed according to the density, width, and multi-row arrangement of the vegetation zone. From numerical simulations, the flow field, vorticity distribution, turbulence distribution, and wave distribution around the vegetation zone were analyzed according to the crest depth, width, density, and multi-row arrangement distance of the vegetation zone. The hydraulic experiment results suggest that the transmission coefficient decreased as the density and width of the vegetation zone increased, and the multi-row arrangement condition did not affect the hydraulic characteristics significantly. Moreover, the numerical simulations showed that as the crest depth decreased, the width and density of vegetation increased along with vorticity and turbulence intensity, resulting in increased wave height attenuation performance. Additionally, there was no significant difference in vorticity, turbulence intensity, and wave height attenuation performance based on the multi-row arrangement distance. Overall, in the case of submerged rigid vegetation, the wave energy attenuation performance increased as the density and width of the vegetation zone increased and crest depth decreased. However, the multi-row arrangement condition did not affect the wave energy attenuation performance significantly.

• 한국수산과학회지
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• 제4권3_4호
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• pp.92-98
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• 1971

부산 항만내 영도 앞바다에서 1967년 9월부터 1968년 10월까지 사이에 채집된 개조개에 대해 비만도와 수은의 계절적인 변화와, 각장과 전중량, 각고와 전중량, 각장과 각폭, 각고와 각폭의 관계를 조사했다. 비만도의 변화는 수온의 변화와 관계를 가지고 있으며, 생식소 발달 과정과 깊은 관계를 가지고 있어 3월 이후 5월까지 점점 높은 값을 보였고, 고온인 8월에는 비만도는 오히려 일시적인 낯아짐을 보였다. 주산란기인 8월하순부터 10월 중순까지 사이에 비만도의 값은 연중 최고값을 보이고, 이후 낮아짐을 볼 수 있었다. 수온이 차츰 낮아져 $10^{\circ}C$ 이하로 되는 $1\~2$월에는 비만 속도는 연중 최소값을 보였다. 각장과 전중량 $$W=0.4749L^{2.62307}$$(수), $$W=0.3438L^{2.77993}$$(암) 각고와 전중량 $$W=0.3221L^{3.06661}$$ 각폭과 전중량 $$W=3.5868L^{2.46646}$$과 같은 곡선식을 보였고, 각장자 각고 Y=0.818x+0.292 (상관계수 r=0.958) 각장과 각폭 y=0.520x+0.200(상관계수 r=0.799)각고와 각폭 y=0.499x+0.516 (상관계수 r=0.773)과 같은 직선을 보였다.

• Journal of the Korean Wood Science and Technology
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• 제24권4호
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• pp.32-39
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• 1996

The overall purpose of this study was to investigate the dimensional changes of melamine sheet laminated medium density fiberboard(MDF) floorings by sub-heating system(Ondol). This study was also conducted to improve the properties of melamine sheet laminated MDF floorings. The effects of density, resin content, manufacturing speed of MDF and types of melamine sheet on dimensional and weight changes of floorings were investigated. The results were as followings. 1. Dimensional and weight change of melamine sheet laminated MDF flooring by heating decreased with decreasing the density of MDF. 2. Dimensional and weight change of melamine sheet laminated MDF flooring by heating decreased with increasing the resin content of MDF. 3. Dimensional and weight change of melamine sheet laminated MDF flooring by heating decreased with decreasing the manufacturing speed of MDF. 4. Dimensional change of melamine sheet laminated MDF flooring in width direction by heating was doubled than that in machine direction. 5. Dimensional change and curling of high pressure melamine laminate(HPM) laminated MDF flooring by heating was less than those of low pressure melamine laminate(LPL) flooring. 6. Weight loss of melamine sheet laminated MDF flooring by heating has linear relationship with shrinkage.

• 한국의류산업학회지
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• 제18권6호
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• pp.776-786
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• 2016

This study intends to suggest production process of circular knitted jackets and dimensional change data of finished clothes after washing. the study provides pattern design method of circular knitted jackets by applying dimensional change. By doing so, the purpose of this study is to increase production efficiency through accurate order in consideration of loss amount of the fabrics in production. With the three fabric materials selected, this study investigated dimensional change of circular knitted jackets after sewing and washing by varying the parts to be attached to padding cloth and with or without inner lining. As for the fabric F-C (including the spandex, thicker and weightier than the other two fabrics), front width shrunk by 4.6%, which showed the biggest shrinkage among the jackets made of test fabrics. Then it suggested design methods of circular knitted jacket patterns to which dimensional change is applied according to materials, and analyzed the amount of fabric required for production by comparison of the materials. When using the fabric F-C without inner lining, there is big dimensional change and more than double amount of fabric is required. It is expected that the research results will be a basic data for pattern design and production process of circular knitted clothing.

• JSTS:Journal of Semiconductor Technology and Science
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• 제14권1호
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• pp.48-52
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• 2014

In this paper, scaling down characteristics of vertical channel phase random access memory are investigated with device simulator and finite element analysis simulator. Electrical properties of select transistor are obtained by device simulator and those of phase change material are obtained by finite element analysis simulator. From the fusion of both data, scaling properties of vertical channel phase change random access memory (VPCRAM) are considered with ITRS roadmap. Simulation of set reset current are carried out to analyze the feasibility of scaling down and compared with values in ITRS roadmap. Simulation results show that width and length ratio of the phase change material (PCM) is key parameter of scaling down in VPCRAM. Thermal simulation results provide the design guideline of VPCRAM. Optimization of phase change material in VPCRAM can be achieved by oxide sidewall process optimization.

• 한국광학회지
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• 제10권4호
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• pp.342-347
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• 1999

광소자의 소형화와 집적화 노력에 따라 광도파로의 도파폭과 곡률 반경이 작아지면서, 그 경계조건을 만족하는 도파모드와 전파상수의 변화가 심하게 되었다. 특히, 도파폭의 좁아지면서 제작 공정상의 폭조절 오차한계 내의 작은 변화에도 전파상수가 크게 변화하게 되어, 배열도파로(Arrayed Waveguide Grating, AWG)소자에서는 각 도파로 진행광의 위상이 설계와 심하게 달라지고 소자의 성능에 영향이 커지게 되었다. 광소자의 소형화에 따라 심각해지는 이러한 근사설계 오차에 의한 영향을 정량적으로 분석하고 대처하기 위해, 여기서는 유효굴절률법(Effective Index Method)과 해석적 함수해(Analytic Solution Method)를 이요하여 여러 도파로 구조를 해석하여 전파특성 변수를 얻어내었다. 또한, 이를 적용하여 자체 제작한 고기능 전산시늉기를 통해 각종 InP-, Silica-AWG 소자의 성능을 모사하였다. 모사 결과는 실제 제작된 전형적인 소자와 비교하여 매우 유사한 경향을 나타내었으며, Ridge-type Inp-AWG 소자의 경우, 도파폭의 허용공차가 0.02$\mu\textrm{m}$ 이내로 개선될 때, AWG 소자의 신호대잡음비(SNR)가 약 -25dB 이상 가능하게 되며 Rib-type Silica-AWG 소자의 경우는 도파폭 허용공차가 0.1$\mu\textrm{m}$ 정도이기만 해도 약 -30dB 이상 가능한 것으로 모사되었다.

• 한국운동역학회지
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• 제12권1호
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• pp.15-30
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• 2002

The purpose of this study was analyzed the effect of kinematical and kinetical factors of lower extremity of form change in the cause of growth an unborn child during in pregnancy. Three pregnant women were selected from pregnant 24 weeks as subjects. Each subjects were required to walk with usual walking speed. Cinematographic and GRF data were collected during walking, and the kinematical and kinetical variables were calculated using Kwon3d. Based on the results of the study, the following conclusions were drawn : 1. Step width and Step length The change of form during the period of pregnancy was not statistically found significant in the step width and the step length. 2. Angle of lower extremity 1) The change of form during the period of pregnancy was not statistically found significant in the hip angle at right heel contact, mid stance, but it was statistically found significant in the hip angle at toe off on p<.05. 2) The change of form during the period of pregnancy was not statistically found significant in the knee angle at right heel contact, mid stance, but it was statistically found significant in the knee angle at toe off on p<.05. 3) The change of form during the period of pregnancy was not statistically found significant in the ankle angle at right heel contact, mid stance, but it was statistically found significant in the ankle angle at toe off on p<.05. 3. Ground reaction force 1) The change of form during the period of pregnancy was statistically found significant in medial-lateral force(Fx) on p<.001. 2) The change of form during the period of pregnancy was not statistically found significant in post-anterior force(Fy). 3) The change of form during the period of pregnancy was statistically found significant in impulse force and minimum peak of vertical reaction force on p<.001, p<.01 but it was not statistically found significant in second maximum force.

• 생물환경조절학회지
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• 제22권2호
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• pp.131-137
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• 2013

본 연구는 자생 덩굴식물인 마삭줄과 후추등의 실내 광도차에 따른 생육특성의 변화를 알아보고자 광도 처리 조합을 3처리구를 만들어 환경 조절 생육상에서 조사하였다. 사용된 광원은 형광등이고, 광 처리를 각각 100lux, 1,000lux, 2,500lux로 달리하여 5개월간 생육특성 변화를 조사하였다. 자생 마삭줄은 저광도인 100lux에서 처리 2개월 이후 생존율이 약 16.7%로 식물체 대부분이 고사하였고, 1,000lux와 2,500lux에서는 처리 5개월까지도 생존율이 83.3%로 높게 유지되었다. 실내광도가 높아짐에 따라 초장, 엽수, 분지수, 엽장 및 엽폭은 증가하는 경향을 보였고 고광도인 2,500lux에서 가장 우세한 생육 및 생장을 보였다. 자생 후추등은 저광도인 100lux에서는 처리 4개월 후 생존율이 50%로 생육이 불량하였으나 1,000lux와 2,500lux에서는 처리 5개월까지도 100%의 높은 생존율을 보였다. 1,000lux 조건에서 엽록소 함량이 증가되는 경향을 보였고, 엽장과 엽폭이 약간 넓어지는 경향은 보였다. 상록성 덩굴식물인 자생 마삭줄과 후추등을 실내 광조건을 달리하여 처리한 결과 두 식물 모두 1,000lux 이상의 광조건에서 생육이 양호하였고 특히 후추등의 경우 마삭줄에 비해 1,000lux의 낮은 광도에서도 생육이 양호하고 잎이 넓어지고 엽색도 짙은 녹색으로 유지되어 실내식물로서 활용성이 높을 것으로 판단되었으나 광도가 지나치게 낮아질 경우 생육이 저조한 것으로 나타나 내 음성이 높다고 할지라도 정상적인 생육을 위해서는 적당한 광조건이 필요함을 알 수 있었다.

• 대한가정학회지
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• 제35권4호
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• pp.79-94
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• 1997

This study was performed to develop a basic stacks pattern for middle-aged women reflecting the characteristics of their lower body types. Anthropometric measurements using sliding guage method were carried out for 4 women 40's For the analysis of the lower body types horizontal and vertical section maps obtained by sliding gauge method and 2 indices were produced. Based on the slacks construction components produced by the drafts of their lower body surface experimental slacks pattern was designed. Multiple comparison test was used to compare 3 existing slacks patterns with the experimental pattern. 1. The results of the body section map analysis were as follows: 1) In the frontal view silhouette of vertical section maps there were less individual differences in items with skeleton landmarks than those without them. 2) In the shape of horizontal section maps waist section represented more round shape than the others and thigh maximum width section had the flattest shape. Flat ratios(depth/width) of subjects were much higer than those of young women which clarified the change of depth was bigger than that of width with aging process. 2. The slacks construction components for pattern drafting were as follows: 1)Ease amount of waist was 0.5cm and front and back waist girth difference was 1.2cm Ease amount of hip was 1,8cm and front and back hip girth difference was 0.7 cm 2) The amount of dart intake incresed in the order of side(4cm) back(3,6cm) from (2.8cm) The length of dart leg incresed in the order of front side back.