• 한국식품조리과학회지
• /
• 제32권4호
• /
• pp.413-425
• /
• 2016

Purpose: This study was conducted to understand the factors that affect the acceptance of gluten-free rice pasta samples prepared with added buckwheat, mungbean, and acorn starches, and to compare sensory characteristics of samples with those of 100% semolina pasta. Methods: Descriptive analysis of pasta was conducted by 12 trained panels. Acceptance test was carried out by 40 consumers using 7-point hedonic scale. Collected data was statistically analyzed by principal component analysis, and partial least squares regression analysis. Results: Quantitative descriptive analysis showed that increasing amount of buckwheat, mungbean, and acorn starches resulted in significant improvement in gluten-free rice pasta properties, especially texture, hardness, chewiness, roughness, and al dente with increasing amount of sample starches, and decreased adhesiveness. In acceptance test, appearance and texture of gluten-free rice pasta with mungbean starch were preferred than pasta made with 100% rice. Flavor and taste was preferred in pasta with buckwheat starch than other pasta samples. Rice pasta with 30% buckwheat starch showed the highest score in overall acceptance among rice samples. Conclusion: This study suggested that adding mungbean starch could improve texture of gluten-free pasta, and adding buckwheat starch would improve taste and flavor of gluten-free rice pasta.

• Structural Engineering and Mechanics
• /
• 제74권2호
• /
• pp.175-187
• /
• 2020

The theories having been developed thus far account for higher-order variation of transverse shear strain through the depth of the beam and satisfy the stress-free boundary conditions on the top and bottom surfaces of the beam. A shear correction factor, therefore, is not required. In this paper, the effect of surface on the axial buckling and free vibration of nanobeams is studied using various refined higher-order shear deformation beam theories. Furthermore, these theories have strong similarities with Euler-Bernoulli beam theory in aspects such as equations of motion, boundary conditions, and expressions of the resultant stress. The equations of motion and boundary conditions were derived from Hamilton's principle. The resultant system of ordinary differential equations was solved analytically. The effects of the nanobeam length-to-thickness ratio, thickness, and modes on the buckling and free vibration of the nanobeams were also investigated. Finally, it was found that the buckling and free vibration behavior of a nanobeam is size-dependent and that surface effects and surface energy produce significant effects by increasing the ratio of surface area to bulk at nano-scale. The results indicated that surface effects influence the buckling and free vibration performance of nanobeams and that increasing the length-to-thickness increases the buckling and free vibration in various higher-order shear deformation beam theories. This study can assist in measuring the mechanical properties of nanobeams accurately and designing nanobeam-based devices and systems.

• 한국방재학회:학술대회논문집
• /
• 한국방재학회 2007년도 정기총회 및 학술발표대회
• /
• pp.181-185
• /
• 2007

A free-surface correction(FSC) method is presented to solve the 3-D shallow water equations. Using the mode splitting process, FSC method can simulate shallow water flows under the hydrostatic assumption. For the hydrostatic pressure calculation, the momentum equations are firstly discretized using a semi-implicit scheme over the vertical direction leading to the tri-diagonal matrix systems. A semi-implicit scheme has been adopted to reduce the numerical instability caused by relatively small vertical length scale compare to horizontal one. and, as the free surface correction step the final horizontal velocity fields are corrected after the final surface elevations are obtained. Finally, the vertical final velocity fields can be calculated from the continuity equation. The numerical model is applied to the calculation of the simulation of flow fields in a rectangular open channel with the tidal influence. The comparisons with the analytical solutions show overall good agreements between the numerical results and analytical solutions.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2005년도 학술발표논문집
• /
• pp.637-642
• /
• 2005

The objective of this study is to evaluate design parameters of free water surface constructed wetland for the reduction of agricultural nonpoint source pollution. From literature review, the key design parameters were selected as influent concentration, influent water volume, hydraulic retention time and wetland system arrangement. The design value for each parameter was established after pilot study. Full-scale constructed wetland on the basis of the designed values was constructed to evaluate those reasonableness. The results of this study showed that the designed values for free water surface constructed wetland were appropriate for the reduction of agricultural nonpoint source pollution.

• 한국농공학회지
• /
• 제43권5호
• /
• pp.106-115
• /
• 2001

This paper deals with the free vibrations of horizontally curved beams partially supported on elastic foundations. Taking account of the effects of rotatory inertia and shear deformation, differential equations governing the free vibrations of such beams are derived, in which the Pasternak foundation model is considered as the elastic foundation. Differential equations are numerically solved to calculate natural frequencies and mode shapes. The experiments were performed in which the free vibration frequencies of such curved beams in laboratorial scale were measured and these results agreed quite well with the present studies. In numerical examples, the circular, parabolic, sinusoidal and elliptic curved members are considered. The parametric studies are performed and the lowest four frequency parameters are reported in tables and figures as the non-dimensional forms. Also the typical mode shapes are presented.

• Macromolecular Research
• /
• 제17권6호
• /
• pp.397-402
• /
• 2009

In emulsifier-free, emulsion polymerization with ionizable comonomer, the ionization of the comonomer is critical in determining the size of the final polymerie particles at sub-micrometer scale. In this study, polystyrene latex beads with carboxylates on the surface were synthesized using acrylic acid as a comonomer. Specifically, ammonium hydroxide was added to the emulsifier-free polymerization system to promote the ionization of acrylic acid by increasing pH. Smaller polystyrene latex particles were produced by increasing the ammonium hydroxide concentration in the reaction system, due to the enhanced stability promoted by the ionization of acrylic acid during the nucleation step. In addition, the surface morphology of the polystyrene latex particles was controlled by the concentration of acrylic acid, the dissociation of which was influenced by the ammonium hydroxide concentration.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 춘계학술대회
• /
• pp.1442-1446
• /
• 2004

The heat (mass) transfer characteristics on the blade surface of a first-stage turbine rotor cascade has been investigated by employing the naphthalene sublimation technique. A four-axis profile measurement system is employed for the measurements of the local heat (mass) transfer coefficient on the curved blade surface. The experiments are carried out for two free-stream turbulence intensities of 1.2% and 14.7%. The high free-stream turbulence results in more uniform distributions of heat load on the both pressure and suction surfaces and in an early boundary-layer separation on the suction surface. The heat (mass) transfer enhancement on the suction surface due to the endwall vortices is found to be relatively small under the high free-stream turbulence.

• Corrosion Science and Technology
• /
• 제3권3호
• /
• pp.87-97
• /
• 2004

This paper presents a new approach with meso scale structure models to express mechanical property, such as stress - strain relationships, of concrete. This approach is successful to represent both uniaxial tension and uniaxial compression stress - strain relationship, which is in macro scale. The meso scale approach is also applied to predict degraded mechanical properties of frost-damaged concrete. The degradation of mechanical properties with frost-damaged concrete was carefully observed. Strength and stiffness in both tension and compression decrease with freezing and thawing cycles (FTC), while stress-free crack opening in tension softening increases. First attempt shows that the numerical simulation can express the experimentally observed degradation by introducing changes in the meso scale structure in concrete, which are assumed based on observed damages in the concrete subjected to FTC. At the end applicability of the meso scale approach to prediction of the degradation by combined effects of salt attack and FTC is discussed. It is shown that clarification of effects of frost damage in concrete on corrosion progress and on crack development in the damaged cover concrete due to corrosion is one of the issues for which the meso scale approach is useful.

• 대한조선학회논문집
• /
• 제51권1호
• /
• pp.8-15
• /
• 2014

In this study, flow characteristics around the hull form of KLNG are investigated by numerical simulations. The numerical simulations of the turbulent flows with the free surface around KLNG have been carried out at Froude number 0.1964 using the FLUENT 6.3 solver with Reynolds stress turbulence model. Several GEOSIM models are adopted to consider the scale effect attendant on Reynolds number. Furthermore, a full scale ship is calculated and the result is compared with the numerical results of GEOSIM models. The calculated results of GEOSIM models and the full scale ship are compared with the experiment data of MOERI towing tank test and Inha university towing tank test. Moreover, wake distribution on the propeller plane of the full scale ship is estimated using the numerical results of GEOSIM models. The prediction result is directly compared with the simulation result in full scale.

• 한국비블리아학회지
• /
• 제30권3호
• /
• pp.59-92
• /
• 2019

본 연구의 목적은 현재 중앙기록물 관리기관인 국가기록원이 장애인을 포함한 모든 이용자들이 동등한 수준으로 기록정보서비스를 이용할 수 있는 서비스 환경이 조성되어 있는지를 평가하고, 미진한 부분에 대해서는 이를 개선할 수 있는 방안을 논의하는 것이다. 이를 위해 첫째, 기록정보서비스 환경을 평가할 수 있는 평가도구 즉 지표와 척도를 개발하고; 둘째, 개발된 척도를 활용하여 중앙기록물 관리기관인 국가기록원 본원, 대통령기록관, 서울 대전 부산기록관(분원)의 기록정보서비스 환경을 계측하여 평가하고; 셋째, 그 평가 결과가 시사하는 바가 무엇인지 분석하여 개선방안을 제언하였다. 새로이 개발한 척도를 사용하여 실제로 국가기록원의 기록정보서비스 환경을 계측한 결과, 일반적이고도 간접적인 서비스 환경 공간인 진입영역과 공용영역에서의 서비스 환경은 우수한 반면, 이용자들에게 직접적인 정보서비스가 이루어지는 공간인 일반서비스 영역과 확장(부가가치)서비스 영역의 환경은 낮게 평가된 것으로 나타났다. 이 조사결과를 바탕으로 비장애인과 장애인 모두 어떠한 장애물 없이 기록정보서비스를 이용할 수 있는 환경조성을 위한 방안과 후속연구를 제언하였다.