• 대한조선학회논문집
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• 제55권4호
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• pp.341-349
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• 2018

Recently, it has been reported that the whipping response, which is the elastic phenomenon of the ship, may be one of the causes of the ship accident. Unfortunately, the commonly used methodology for evaluating the whipping effect effectively has not been developed yet. In this study, we developed a procedure to estimate the whipping effect of hull in actual design stage. Fluid-structure interaction analysis was performed for a dominant short term sea state to obtain the time series data of vertical wave bending moment including the whipping response by slamming. In order to estimate the whipping effect by using the time series, some signal processing and statistical techniques such as low pass filtering, Weibull fitting and so on, were applied. the hydro-elasticity analysis was performed on container ships of various sizes to evaluate the whipping effect. The parameters that can affect the response of the hull vibration was selected and the effect of these parameters on whipping was analyzed.

• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.387-398
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• 2020

In the design stage of the very large container ships, some methodologies for the whipping effects have been developed, but most of them are based on single sea state. We developed a methodology that considers multiple sea states. Fluid-structure Interaction (FSI) analyses with one dimensional structural model were carried out to capture slamming-induced transient whipping behaviors. Because of the nature of random phases of the applied wave spectra, the required period for entire FSI analyses was determined from the convergence study where the whipping effect became stable. Low pass filtering was applied to the transient whipping responses to obtain the hull girder bending moment processes. Peak counting method for the filtered whipping responses was used to obtain collection of the vertical bending moment peaks. The whipping effect from this new method is compared with that from based on single sea state approach. The efficiency and advantage of the new methodology are presented.

• 대한조선학회 특별논문집
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• 대한조선학회 2017년도 특별논문집
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• pp.80-87
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• 2017

This paper is related to structural assessment considering the hydroelastic response of ultra large container ships, especially from whipping (bow or stern impacts) and from springing (resonance). In general, whipping contributes both to increased fatigue and extreme loading, while springing does mainly contribute to increased fatigue loading. To evaluate the hydroelastic response quantitatively with high accuracy, numerical code considering hydro-structure coupling was applied and fatigue strength of a 13,100 TEU class containership was verified. The segmented model test and full scale measurement were also needed to assess the effect of whipping and springing on the fatigue and extreme capacity in more realistic way and for verification of the numerical tools. With reference to class rule, fatigue assessment considering springing effect and extreme assessment considering whipping effect were introduced.

• 한국축산식품학회지
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• 제42권5호
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• pp.889-902
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• 2022

With increasing consumer demand for "clean label" products, the use of natural ingredients is required in the food industry. Protein/polysaccharide complexes are considered good alternatives to synthetic emulsifiers and stabilizers for formulating stable emulsion-based foods. Milk protein and carrageenan are widely used to improve the physical properties and stability of dairy food products. In a previous study, milk protein isolate (MPI) was conjugated with 𝛋-carrageenan (𝛋-Car) in a wet-heating system through the Maillard reaction, and the Maillard conjugates (MC) derived from MPI and 𝛋-Car effectively improved the stability of oil-in-water emulsions. Therefore, MPI/𝛋-Car conjugates were used in whipping cream as natural emulsifiers in this study, and the physical and rheological properties of whipping creams stabilized using MPI/𝛋-Car MC and MPI/𝛋-Car electrostatic complexes (EC) were investigated. The whipping creams stabilized with MPI/𝛋-Car MC have lower rheological parameters (η_a,50, K, G', and G'') than those of whipping creams stabilized with MPI/𝛋-Car EC. Although the overrun value was slightly reduced owing to the addition of MPI/𝛋-Car MC, the stability of the whipped creams with MC was effectively improved due to enhanced water-holding ability by conjugation.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.857-862
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• 2004

The present study was carried out to examine the changes in functional properties of cholesterol-removed compound whipping cream made by $\beta$-CD treated cream and palm oil. Six different ratios of cream to palm oil (10:0 as control, 9:1, 8:2, 7:3, 6:4, and 5:5, v/v) were tested. The overrun percentage increased with an increased amount of palm oil. When the ratio of cream to palm oil was 10:0 (control), the overrun was 130%, which was significantly lower than other ratios reached to 150%. Foam instability was measured as 3.1 ml defoamed cream in control, however, the value of foam instability decreased with an increase of palm oil addition. The TBA value of cholesterol-removed compound whipping cream increased from 0.08 to 0.13 with no addition of palm oil during 4 wk storage. When the ratio of cream to palm oil was 5:5, TBA value increased dramatically at 3 wk and thereafter. Among sensory characteristics, texture value increased with higher amount of palm oil, however, flavor and overall preferences were opposite. Above results indicated that partial substitution of palm oil in manufacture of cholesterol-removed compound whipping cream resulted in a stable foam development with little adverse effect on flavor and lipid oxidation during storage. The present study showed a possible application in manufacture of cholesterol-removed compound whipping cream, which may be effective in other foods.

• 대한조선학회논문집
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• 제58권6호
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• pp.400-406
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• 2021

The primary effect of the far-field underwater explosion (UNDEX) is the whipping of the ship hull girder. This paper aims to verify why inelastic effects should be considered in the whipping response estimations from the UNDEX simulations. A navy ship was modeled using Timoshenko beam elements over the ship length uniformly keeping the constant midship section modulus. The transient UNDEX pressure was produced using two types of the Geers-Hunter doubly-asymptotic models: compressible and incompressible fluids. Because the UNDEX model based on incompressible fluid assumption provided more increased fluid volume acceleration in the bubble phase, the incompressible fluid-based UNDEX model was adopted for the inelastic whipping response analyses. The non-linear hull girder bending moment-curvature curve was used to embed inelastic effects in the UNDEX analyses where the Smith method was applied to derive the non-linear stiffness. We assumed two stand-off distances to see more apparent inelastic effects: 40.5 m and 35.5 m. In the case of the 35.5 m stand-off distance, there was a statistically significant inelastic effect in terms of the average of peak moments and the average exceeding proportional limit moments. For the conservative design of a naval ship under UNDEX, it is recommended to use incompressible fluid. In the viewpoint of cost-effective naval ship design, the inelastic effects should be taken into account.

• 한국식품과학회지
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• 제23권2호
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• pp.212-216
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• 1991

유과제조시 가장 걸림돌이 되는 꽈리치기 공정과 반데기 제조공정의 연속공정화 및 표준화를 위하여 기존 chopper의 구조를 변경하고 conveyer를 연결하여 기계화 가능성을 시도하였다. Plate와 die를 새로 제작하여 실험한 결과 꽈리치기 및 반데기를 연속적으로 제조할 수 있었으며, 그 품질도 기존방법에 비하여 차이가 없었다. 반데기의 두께와 폭은 conveyer belt의 속도를 조절하므로써 가능하였으며, chopper에서 반죽의 토출량이 221.8g/sec($Slit\;:\;5{\times}50.5\;mm$)일 때 conveyer의 속도는 87.3 mm/sec가 바람직하였다. Chopper의 구성에서 knife나 plate의 모양 등은 꽈리치기 효과에 큰 영향을 주지 않았으며, 건조 후 반데기의 두께는 $3.0{\sim}3.5\;mm$인 경우 가장 좋은 유과품질을 얻었다. Chopper를 통과하는 횟수는 품질에 큰 영향을 주지 않으나 전연 꽈리치기 하지않은 경우 조직은 대단히 유약하였다.

• 한국해양공학회지
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• 제33권1호
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• pp.33-41
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• 2019

Estimating fatigue damage is a very important issue in the design of ships. The springing and whipping response, which is the hydro-elastic response of the ship, can increase the fatigue damage of the ship. So, these phenomena should be considered in the design stage. However, the current studies on the the application of springing and whipping responses at the design stage are not sufficient. So, in this study, a prediction method was developed using fluid-structural interaction analysis to assess of the fatigue damage induced by springing and whipping. The stress transfer function (Stress RAO) was obtained by using the 3D FE model in the frequency domain, and the fatigue damage, including linear springing, was estimated by using the wide band damage model. We also used the 1D beam model to develop a method to estimate the fatigue damage, including nonlinear springing and whipping by the vertical bending moment in the short-term sea state. This method can be applied to structural members where fatigue strength is weak to vertical bending moments, such as longitudinal stiffeners. The methodology we developed was applied to 325K VLOC, and we analyzed the effect of the springing and whipping phenomena on the existing design.

• 대한조선학회논문집
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• 제39권3호
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• pp.64-74
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• 2002

선체 휘핑 해석 전용 프로그램은 모멘텀 슬래밍 이론을 사용하여 비선형 유체충격력을 추정하였으며, Timoshenko 보이론에 기초하여 선체 hull girder를 탄성체로 모델링하고 있다. 개발된 프로그램에 대하여 슬래밍 충격력의 효과, 유탄성해석의 효과 그리고, 선속, 파고, 파장 등 각종 설계 변수가 미치는 효과 등에 관한 검증 계산을 수행하였고, 실제 선박 설계에의 적용 예를 보임으로써 본 프로그램의 설계 활용성을 확인하였다. 본 프로그램은 각종 입출력자료의 GUI 처리 및 선박 운동에 대한 시뮬레이션 제공 등 다양한 기능과 특성을 가지고 있다.

• Earthquakes and Structures
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• 제15권2호
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• pp.203-214
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• 2018

Deflection control in tall buildings is a challenging issue. Connecting of the towers is an interesting idea for architects as well as structural engineers. In this paper, two reinforced concrete core-wall towers are connected by a truss bridge with buckling restrained braces. The buildings are 40 and 60-story. The effect of the location of the bridge is investigated. Response spectrum analysis of the linear models is used to obtain the design demands and the systems are designed according to the reliable codes. Then, nonlinear time history analysis at maximum considered earthquake is performed to assess the seismic responses of the systems subjected to far-field and near-field record sets. Fiber elements are used for the reinforced concrete walls. On average, the inter-story drift ratio demand will be minimized when the bridge is approximately located at a height equal to 0.825 times the total height of the building. Besides, because of whipping effects, maximum roof acceleration demand is approximately two times the peak ground acceleration. Plasticity extends near the base and also in major areas of the walls subjected to the seismic loads.