• Food Science and Industry
• /
• v.53 no.1
• /
• pp.43-55
• /
• 2020

Most reports demonstrated the substrate specificity-based kinetic properties of chitin or chitosan degrading enzymes. However, there is virtually less information on the high quality and quantity production of chitin or chitosan hydrolysates having a larger than (GlcN)₇ from the hydrolysis of high molecular weight chitosan using specific enzymes and their biological activity. Therefore, the production of such molecules and the discovery of such enzyme sources are very important. Fortunately, the author has established a mass production method of chitosan hydrolysates (GlcN)_n, n=2-13 that have been characterized as a potent antioxidant substance, as well as antifungal and antibacterial activities against Penicillium species and highly selective pathogenic bacteria. In addition, preclinical studies using (GlcN)_n, n=5-25 demonstrated that these molecules played a very important role in maintaining biometric balance. Collectively, it is implicated that the application of these mixed substances to foods with significant biological activity is very encouraging.

• Food Science and Industry
• /
• v.49 no.4
• /
• pp.82-93
• /
• 2016

Although the development of food technology is relatively fast, it's application is very broad. So, it is necessary that quantitative analysis method can be introduced in analysing of research trends and implication of research themes. Most countries do not classify in food additives as synthesis or natural. However, the use of natural food additives should be recommended by considering about health safety. In this regard, quantitative analysis based on bibliographic information of patents and papers is vital to analyse the trend of research on natural food additives. The data regarding with natural food additives was assigned patents and published papers in the world from 1996 to March 2016 and Thomson Innovation, analysis program was provided by Thomson reuters.

• Food Science and Industry
• /
• v.51 no.1
• /
• pp.61-71
• /
• 2018

The evaluation of food taste is one of the important activities of human consciousness and it is practiced by sensory analysis using 5 terminal sensorial consciousness among many other functions. These consciousness activities may be conducted by 3 way branching transformation (3-WBT) logic, which choose one out of 3 options under the multi-layered consciousness decision making system. On the basis of this logic, cognitive sensory evaluation (CSE) method was developed to carry out questionnaire survey covering objective and subjective issues during consumption of food for pregnant women. The results of the CSE for several food items was presented with the Table-pattern called CSET covering consciousness factors and their effects on the food consumers.

• Food Science and Industry
• /
• v.53 no.2
• /
• pp.183-199
• /
• 2020

Traditional food is the basis of Korean food, but in the process of industrialization, Japanese soybean fermented product making method became standardization process of Korean soybean fermented product as a factory type. As a result, traditional fermented food was pushed behind the industrialization. At present, there is anxiety in the development of the fermented soybean product industry due to the gap in management level between the manufacturers, the decrease in consumption of Jangryu due to changes in dietary life, and the negative image as high salt food. In order to overcome these problems and lead continuous growth, governmental industrial development policies such as traditional liquor and Kimchi are inevitably needed. By laying the legal and institutional foundation and making good use of it in industry, it will be the foundation for continuous development in the market where fierce competition is accelerated.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.12 no.1
• /
• pp.85-101
• /
• 2020

The optimal parameters for the fluid-structure interaction analysis using the Smoothed Particle Hydrodynamics (SPH) for fluids and finite elements for structures, respectively, are explored, and the effectiveness of the simulations with those parameters is validated by solving several open surface fluid problems. For the optimization of the Equation of State (EOS) and the simulation parameters such as the time step, initial particle spacing, and smoothing length factor, a dam-break problem and deflection of an elastic plate is selected, and the least squares analysis is performed on the simulation results. With the optimal values of the pivotal parameters, the accuracy of the simulation is validated by calculating the exerted force on a moving solid column in the open surface fluid. Overall, the SPH-FEM coupled simulation is very effective to calculate the fluid-structure interaction. However, the relevant parameters should be carefully selected to obtain accurate results.

• Food Science and Industry
• /
• v.55 no.1
• /
• pp.74-94
• /
• 2022

With the discovery of metabolic mechanisms of alcohol fermentation and acetic acid fermentation in the 1800s and 1900s, the history of traditional vinegar became a turning point for changing to the history of science and technology. Since then, innovation in vinegar production has occurred, and the era of full-scale mass industrialization has opened. The most modern method, submerged fermentation, has improved the vinegar production process to produce much higher quality vinegar and provide vinegar with high productivity and quality uniformity. Innovative research for vinegar production is underway as various approaches have been developed to increase fermentation efficiency, reduce costs, and shorten fermentation time due to the trend of combining existing technologies and advanced technologies. Now that the development of the vinegar industry is currently focused on vinegar engineering, multidisciplinary approaches in various fields such as microbiology, chemistry, food technology, process engineering, and molecular biology are needed.

• Journal of Ocean Engineering and Technology
• /
• v.25 no.2
• /
• pp.15-20
• /
• 2011

This study aimed at validating the adopted numerical methods to solve two-phase flow around a two-dimensional (2D) rectangular floating structure in regular waves. A structure with a draft equal to one half of its height was hinged at the center of gravity and free to roll with waves that had the same period as the natural roll period of a rectangular barge. In order to simulate the 2D incompressible viscous two-phase flow in a wave tank with the rectangular barge, the present study used the volume of fluid (VOF) method based on the finite volume method with a standard turbulence model. In addition, the sliding mesh technique was used to handle the motion of the rectangular barge induced by the fluid-structure interaction. Consequently, the present results for the flow field and roll motion of the structure had good agreement with those of the relevant previous experiment.

• 유체기계공업학회:학술대회논문집
• /
• 2002.12a
• /
• pp.504-512
• /
• 2002

Bileaflet mechanical valves have the complications such as hemolytic and thromboembolic events, leaflet damage, and leaflet break. These complications are related with the fluid velocity and shear stress characteristics of mechanical heart valves. This fact makes clear the importance of determining the fluid velocity and shear stress characteristics of mechanical heart valves, and requires a detailed understanding of these system properties and further substantial research. The first aim of current study is to introduce fluid-structure interaction method for calculation of unsteady and three-dimensional blood flow through bileaflet valve and leaflet behavior interacted with its flow, and to overcome the shortness of previous studies, where the leaflet motion has been ignored or simplified, by using FSI method. To accomplish this goal, a finite volume computational fluid dynamics code and a finite element structure dynamics code have been used concurrently to solve the flow and structure equations, respectively, to investigate the interaction between the blood flow and leaflet. Physiologic ventricular and aortic pressure waveforms were prescribed as flow boundary conditions. The interaction of aortic flow and valve motion were computed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.05a
• /
• pp.275-282
• /
• 2007

In this study, a fluid-structure interaction (FSI) analysis system has been developed in order to evaluate the turbine cascade performance with blade structural deformation effect. Relative movement of the rotor with respect to stator is reflected by modeling independent two computational domains. To consider the deformed position of rotor airfoil, dynamic moving grid method is applied. Reynolds-averaged Navier-Stokes equations with one equation Spalart-Allmaras and two-equation SST $k-{\varepsilon}$ turbulence models are solved to predict unsteady fluid dynamic loads. A fully implicit time marching scheme based on the Newmark direct integration method with high artificial damping is used to compute the fluid-structure interaction problem. Cascade performance evaluations for different elastic axis positions are presented and compared each other. It is importantly shown that the predicted aerodynamic performance considering structural deformation effect of blade can show some deviations compared to the data generally computed from rigid blade configurations and the position of elastic axis also tend to give sensitive effect.

• Journal of the Society of Naval Architects of Korea
• /
• v.57 no.2
• /
• pp.61-69
• /
• 2020

Due to its flexibility of the composite propeller blade, it is necessary to design a shape capable of generating a desired load at a design point in consideration of the shape change of the propeller. In order to design it, we need to evaluate not only the hydrodynamic force around it, but also its structural response of flexible propeller according to its deformation. So, it is necessary to develop a design tool to predict the hydroelastic performance of a flexible propeller with deformation considering fluid-structure interaction and special operating conditions. Finally a design optimization tool for flexible propellermade of CFRP is required. In this study, a design methodology of the specific flexible composite propeller is suggested, considering fluid-structural interaction analysis of the specific flexible propeller.