• Journal of the Society of Naval Architects of Korea
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• v.31 no.4
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• pp.32-40
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• 1994

This paper describes a smooth surface interpolating method of ship hull using a three-dimensional currie net that comes from the mesh curve fairing process. Geometric continuity(($GC^1$) is preserved across the boundary curve between patches. The three-dimensional curve net can have nonrectangular topologies, such as triangular and pentagonal topology. Among the boundary curve interpolation methods, Hermite blended Coons patch, Convex combination, and Gregory patch interpolation method are used to generate the ship hull surface. To check the fairness of the surface, the numerical method of surface/surface intersection problem is adopted. An application to an actual ship hull is given as an example.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.21-21
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• 2022

충적하천의 하상과 제방은 흐름에 의해 쉽게 침식되는 사립자들로 구성되어 있다. 흐름이 더욱 강해지면 커다란 입자들도 움직이게 되고 더욱 커지면 결국 모든 입자들이 움직인다. 이렇게 흐름에 의해 하상과 제방을 구성하는 사립자들이 움직이기 시작하는 상태를 한계운동이라 하며, 이때의 흐름조건을 한계조건이라 한다. 한계조건은 이동상 수리학의 시작으로, 이때부터 흐름은 물과 유사의 혼합이라는 이상류가 되어 순수한 물의 흐름보다 더 복잡하게 된다. 개수로는 관수로와 달리 반드시 자유수면이 있으며, 따라서 물과 공기와의 마찰은 상대적으로 매우 작으므로 개수로의 전단응력 분포는 관수로와 달리 근본적으로 비대칭이다. 따라서 전단응력은 수로 바닥이나 측벽에서만 작용하게 된다. 한계조건은 이러한 추상적인 의미에 앞서 바닥이 침식되지 않는 하도나 수로의 설계 등에 기본적인 자료가 된다. 개수로에서 경계면의 전단응력을 힘으로 표시하는 것을 통상 소류력이라 하며, 개수로 경계면에서 전단응력의 분포도; 이른바 단면의 평균 전단응력의 개념을 도입하여 해석하고 설계기준으로 제시되고 있다. 본 연구에서는 자연하천과 유사한 조건의 건설기술연구원 하천실험센터의 급경사수로에서 연구를 진행하였으며, 기존 연구를 바탕으로 제작된 소류력 측정장치를 이용하였다. 하천의 설계나 평가에 적용되는 평균 소류력 개념은 복잡한 난류흐름에서 평가지표로써 대표하기 힘들기 때문에 유사 하천환경의 바닥에서 발생하는 소류력을 직접 측정하고자 연구를 진행하였고, 연구결과를 기존의 소류력 산정방법과 비교하였다. 본 연구에 사용된 장치는 실규모 실험을 위해 제작되었으며, 실규모 적용성 검토를 위해 실험실에서 충분한 검증실험을 거친 후 실규모 실험에 적용하였다.

• Journal of Korea Water Resources Association
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• v.56 no.2
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• pp.103-113
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• 2023

The river confluence is a section in which two rivers with different topographical and hyrodynamic characteristics are combined into one, and it is a section in which rapid flow, inflow of sediments, and hydrological topographic changes occur. In the confluence section, the flow of fluid occurs due to the difference in density due to the type of material or temperature difference, which is called a density flow. It is necessary to accurately measure and observe the confluence section including a certain section of the main stream and tributaries in order to understand the mixing behavior of the water body caused by the density difference. A comprehensive analysis of this water mixture can be obtained by obtaining flow field and flow rate information, but there is a limit to understanding the mixing of water bodies with different physical properties and water quality characteristics of rivers flowing with stratigraphic flow. Therefore, this study attempts to grasp the density flow through the water temperature distribution in the confluence section. Among the extensive data of the river, vertical data and water surface data were acquired, and through this, the stratification phenomenon of the confluence was to be confirmed. It was intended to analyze the mixed pattern of the confluence by analyzing the water mixing pattern according to the water temperature difference using the vertical data obtained by measuring the repair volume by installing the ADCP on the side of the boat and measuring the real-time concentration using YSI. This study can supplement the analysis results of the existing water quality measurement in two dimensions. Based on the comparative analysis, it will be used to investigate the current status of stratified sections in the water layer and identify the mixing characteristics of the downstream section of the river.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.146-150
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• 1982

In order to improve the nutritional and cooking quality of noodle, and to develop the utility of mungbean, the mungbean-wheat composite flour which contained 20, 40 and 60% mungbean flour were prepared. The characteristics and the noodle-making properties of the composite flours were examined. The water absorption of the composite flour decreased with the increase of the mungbeen content. Amylograph data showed that the more mungbean the composite flour contained the higher the initial pasting temperature of the flour was. The composite flour containing 40% mungbean flour showed the maximum viscosity. Analysis of the textural characteristics of the noodles indicated that the more mungbean flour the noodle contained the more hard, cohesive and gummy the noodles were. Analysis of the turbidity of the fluid obtained after cooking the noodles showed that the turbidities of noodles containing 20 and 40% mungbean were lower than that of wheat flour alone. The quality and sensory tests showed that the noodles of the composite flour containing 20 and 40% mungbean flour were superior to those of wheat flour alone.

• Journal of the Korea Convergence Society
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• v.13 no.5
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• pp.401-411
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• 2022

The purpose of this study was to identify the convergence factors influencing learning satisfaction of nursing students in the COVID-19 pandemic after applying non-face-to-face mixed classes consisted of both real-time and non-real time distance educations. The participants were 109 nursing students who attended in a university and completed the self-report questionnaire. Data were analyzed using the SPSS 23.0 program. The results showed that the learning flow was 3.41, self-regulated learning ability was 3.75, and learning satisfaction was 3.98. Learning satisfaction showed a positive correlation with learning flow (r=.42, p<.001) and self-regulated learning ability (r=.75, p<.001). In addition, the factors influencing the learning satisfaction of the subjects of this study were self-regulated learning ability (𝛽=.662) followed by 60.6% (F=25.63, p<.001). Therefore, to enhance learning satisfaction of nursing students, it is necessary to increase their self-regulated learning abilities and to develop and apply training program considering the needs of the educational environment change in the post-COVID-19 era.

• Applied Biological Chemistry
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• v.31 no.1
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• pp.65-78
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• 1988

This study aims effective use of soymilk residue, by-product of soymilk production, and making noodles by mixing soymilk residue with wheat flour. The results of viscosity property, cooking test of dry noodles, texture test of cooked noodles, and sensory test of cooked noodles were as follows. The color of cooked noodles were slightly shifted to yellowness according to the mixing of soymilk residue. The mixing of soymilk residue resulted in the decrease of texture and the loss of solids due to the decrease of visccelasity. Na-alginate, Na-C.M.C., guar gum, and crude gluten were added to improve the texture of noodles mixed with soymilk residue. As the results, either Na-alginate or guar gum was very effective in increasing the viscosity of composite flour and either guar gum or crude gluten was very effective in improving cooking quality. The texture of noodles supplemented by Na-alginate 1.0%, Na-C.M.C. 2.0%, guar gum 0.5%, or crude gluten 2.0% was similar to that of wheat flour noodles. Complex additives mixed with two different additives were very effective in improving noodle-making characteristics. Especially, the properties of the soymilk residue mixed noodles supplemented by crude gluten 1.0% and Na-C.M.C. 1.0% or crude gluten 1.0% and gum 0.5% were nearly the same in the texture organoleptic properties compared with those of wheat flour noodles.

• Journal of dental hygiene science
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• v.16 no.5
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• pp.349-354
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• 2016

The purpose of this study was to evaluate the efficacy of the newly-developed $Qraypen^{TM}$ (All In One Bio, Korea) system for the diagnosis of early proximal caries by comparing it with the conventional methods of visual inspection and periapical radiography. This study was carried out from July 2015 to April 2016 targeting 32 children aged 7~12 years who visited Y-Dental Clinic for school oral health examinations. Two investigators selected and examined a total of 153 primary molars that had not undergone restorative treatment. Comparisons were carried out between visual inspections, readings of posterior periapical radiography images, and readings of $Qraypen^{TM}$ images. This study revealed that the percentage of interproximal surfaces of primary molar teeth without caries incidence was 83.7% using $Qraypen^{TM}$ imaging and 84.9% using visual inspection and periapical radiography. The differences between the two methods were not statistically significant. Thus, $Qraypen^{TM}$ is expected to be a useful and convenient auxiliary diagnostic device that can facilitate the detection of hidden proximal caries in primary molars.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.469-476
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• 2012

In this paper, a finite element domain decomposition method using local and mixed Lagrange multipliers for a large scal structural analysis is presented. The proposed algorithms use local and mixed Lagrange multipliers to improve computational efficiency. In the original FETI method, classical Lagrange multiplier technique was used. In the dual-primal FETI method, the interface nodes are used at the corner nodes of each sub-domain. On the other hand, the proposed FETI-local analysis adopts localized Lagrange multipliers and the proposed FETI-mixed analysis uses both global and local Lagrange multipliers. The numerical analysis results by the proposed algorithms are compared with those obtained by dual-primal FETI method.

• Korean Journal of Food Science and Technology
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• v.23 no.6
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• pp.745-749
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• 1991

Soybean protein isolate was fermented using lactic acid bacteria. The properties of the lactic fermented soybean protein (LFSP) was compared with those of the lactic fermented rice (LFR). The LFSP was superior in nutritive value and rheological properties, whereas the LFR in color, flavor and taste. Mixing of the LFR and the LFSP was attempted to utilize the merits of both the LFR and the LFSP. The mixture was named Risogurt. The Risogurt had better flavor, taste, color and overall eating quality than the LFSP, and better nutritive value and consistency than the LFR. The optimum mixing ratio for the production of the Risogurt was 75% LFR and 25% LFSP.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.763-768
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• 2011

The effects of $CO_2$-dilution on combustion instability were studied in order to apply biogas in a dual lean premixed gas turbine combustor on a real-scale dual lean premixed burner head which is originally developed for Natural Gas fuel. Combustion instability is reduced by $CO_2$ dilution effect according to the result of dynamic pressure signal and phase-resolved $OH^*$ images. The reason for this is that dilution of $CO_2$ reduces heat release perturbation and increases flame volume due to reduction of the flame speed and expansion of flame surface.