• Journal of the Society of Naval Architects of Korea
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• v.52 no.4
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• pp.338-348
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• 2015

In this study, the added resistance of ships in short waves is systematically studied by using two different numerical methods - Rankine panel method and Cartesian grid method – and existing asymptotic and empirical formulae. Analysis of added resistance in short waves has been preconceived as a shortcoming of numerical computation. This study aims to observe such preconception by comparing the computational results, particularly based on two representative three-dimensional methods, and with the existing formulae and experimental data. In the Rankine panel method, a near-field method based on direct pressure integration is adopted. In the Cartesian grid method, the wave-body interaction problem is considered as a multiphase problem, and volume fraction functions are defined in order to identify each phase in a Cartesian grid. The computational results of added resistance in short waves using the two methods are systematically compared with experimental data for several ship models, including S175 containership, KVLCC2 and Series 60 hulls (C_B = 0.7, 0.8). The present study includes the comparison with the established asymptotic and empirical formulae in short waves.

• The Korean Journal of Health Service Management
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• v.14 no.1
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• pp.137-146
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• 2020

Objectives: The aim of this study was to investigate cognitive function decline by socio-demographic and health-related characteristics (health behaviors and health status) using 5th Korean Longitudinal Study of Aging panel data. Methods: The subjects were 4,440 community-dwelling people aged over 57 years. The data were analyzed with descriptive statistics, frequency analysis, χ²-test, and binary logistic regression analysis using SPSS ver. 25.0. Results: The findings revealed that socio-demographic characteristics (gender, age, area of residence, educational level, marital status, number of children, number of grand-children) and health-related characteristics (smoking, drinking, regular exercise, weight category by body mass index, hypertension and diabetes mellitus) were factors that influenced cognitive function decline (p<.05). Conclusions: Cognitive function decline was closely related to health behaviors and disease types. Future studies must examine related constructs to accurately determine these relationships among various populations. The present study could be used as a tool for the development and implementation of health promotion and prevention strategies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.247-248
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• 2018

In order to secure the variability of long-life housing, dry walls are used. The composite gypsum board panel is the most frequently used infill system for the wall, and it is an excellent construction method in terms of constructability and economic feasibility. However, there are also problems such as the destruction of Ondol pipes at the bottom floor and being unable to fix the light weight steel frame (M-bar) when a variable composite gypsum board panel is used. To solve such problems, a wall with a method of fixing only the top part without fixing the bottom floor is developed, but it is difficult to identify the durability of ceiling frame according to the tensile force of stud and the safety according to the Stiffness and impact resistance (soft body) of ceiling frame. Therefore, this study verified the effectiveness of infill system for the wall by conducting experiment on the stiffness and impact resistance of composite gypsum board panel according to the reinforcement of ceiling frame (wooden frame, double saw-toothed bracket, Cross M-bar). As a result, it was possible to secure the safety of wooden frame while the impact resistance and the Stiffness of double saw-toothed bracket and cross M-bar were not secured.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.5 s.170
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• pp.113-120
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• 2005

Because of the turbulent markets and the increasing demand on product quality, the application of new technology to practice is increasingly important. In case of automotive industries, they take interest in laser welding to solve these problems because laser welding has many advantages such as good accessibility, welding quality, fast welding speed and so on. To apply this technology to welding of car body, the data of laser welding are collected through lots of the experiment according to the material, geometry and layer number of welding points. Based on the experiment results and the information of product, i.e. the car side panel, the clustering of stitches for laser welding was carried out and the optimal equipments are selected through the comparison between the requirements of welding and the potential of equipments. Using these results, laser welding cell for the car side panel are configured with the concept of the digital manufacturing, which ensures maximum planning security with visualization and simulation. Finally, the optimal laser welding cell is chosen by the evaluation of alternative cells with assessment criteria.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.43-54
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• 2021

Human capital and innovation capacities are essential elements and one of the sustainable approaches to driving economic growth. However, there is debate among scholars concerning these two factors in fostering economic growth. This study investigates the relationships between human capital and innovation capacity and economic growth in selected ASEAN countries, namely, Malaysia, Thailand, and Indonesia. Economists widely discussed the interrelation of human capital and innovation. A large body of literature stated that human capital is an essential factor and engine of economic growth. Innovation has become key in transforming the economic development of developing countries. We analyze human capital (HC) and innovation capacity (INC) using static panel data analysis. The data analysis shows that the fixed-effect model is the best model in this study. Further, human capital (HC) has a significant positive relationship with economic growth. Meanwhile, innovation capacity has no significant relationship with economic growth. We also found that Malaysia's coefficient of human capital and innovation capacity is higher and more efficient than in Thailand and Indonesia. In conclusion, human capital and innovation capacity are crucial elements for measuring economic growth. Skilled human capital contributes significantly to the economic growth and economic development of a nation.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.2
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• pp.88-94
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• 2000

For efficient operation, vital hand controls must be easily controlled by the operator from his or her normal working position. The primary working area based on the operator-perceived working comfort was developed to serve as a design guideline to the control panel layout. Six male and four female subjects voluntarily participated in the experiment in which working comfort was measured for two types of controls - knob and lever. The operator-perceived working comfort was examined for the frontal and sagittal distances from the body center and the slope of a work surface. The response surface methodology using a central composite design was employed to develop a prediction model for operator's working comfort on each type of controls. The proposed working areas based on the actual working comfort of an operator avoided the dichotomy that considers only the reachability of control devices, and showed a distinct shape, when compared to the existing normal working areas following the Farley's concept. It was shown that the distance from the body to control devices and the slope of a work surface have a quadratic relationship to the working comfort, and that the most comfortable area for seated tasks is located at the distance of about 2∼4 cm in the sagittal direction and about 42∼43 cm in the frontal direction from the shoulder, respectively. It was also found that the working comfort varies within the working area even at the positions with an equal distance from the body. It is expected that the isocomfort working area generated in the study will be used as a useful guideline for control panel layout.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.21-32
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• 1992

Numerical solutions are presented for solving the free surface flow created by a three-dimensional body moving beneath the free surface with constant velocity at an angle of attack. The solution is obtained using a panel method based on the perturbation potential, which employs Havelock sources and normal dipoles distributed on the body surface and Havelock normal dipoles in the wake downstream of the trailing edge. A pressure Kutta condition with an iterative solution procedure is implemented to satisfy equal pressure condition on the upper and lower surfaces at the trailing edge. Numerical calculation examples in the present paper include an ellipsoid at zero angle of attack, a rectangular planform wing at a small angle of attack in the limit of zero Froude number and then free surface flows and hydrodynamic forces acting on the submerged spheroid and parabolic strut are calculated. Discussions are made about the validity of the present method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.2
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• pp.213-221
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• 2011

In this study, we discussed the weight reducing of a urban railway-car body, in particular, of the Korean EMU, by optimizing topology and size of aluminum extrusion profiles. The heaviest parts of aluminum railway-car bodies, i.e., the base plate of underframe and side panels of side frame composed of double skin structures are considered for optimization. Topology optimization process is applied to obtain get an optimized rib structure for the base plate. The thickness of ribs and plates of the topologically optimized base plate and the existing side panel are also optimized by employing the size optimization process. The results are verified by comparing the maximum von Mises stresses and maximum deformation in the case of the existing design with those in the case of the optimized design. It is shown that the weight of a base plate and side panel can be reduced by 12% and that the weight of the whole car body can be reduced by 8.5%.

• The Research Journal of the Costume Culture
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• v.30 no.6
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• pp.828-841
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• 2022

This study aims to develop a fitted torso pattern suitable for males in their forties and fifties who are obese-a group that accounts for more than fifty percent of men in this age group-using a 3D virtual fitting program. Size Korea's 2022 data for obese males in their forties and fifties is utilized for this study. In terms of the research method, a 3D program (CLO 3D) is used to implement the target group's various body types and to apply fitted torsos that enable verification and evaluation of the pattern's fit and ease. The characteristics of fitted torso patterns for obese bodies are as follows: the front centerline is a profile line; shoulder darts are added by reflecting waist-abdominal protrusion in the front panel; and shoulder, arm, waist, and center-back darts are constructed for the back panel. For obese bodies, the minimum circumference ease amounts should be approximately 6-7cm for the chest, 6cm for the waist, and 6-7cm for the hips. Based on an evaluation of the virtual fit of the developed fitted torso pattern, the data shows that a pattern (foundation) such as this is well suited for obese body types with an average of 4.67/5 points for reverse triangular obesity, an average of 6.67/7 points for log obesity, and an average of 6.69 points for the ease amount.

• Journal of Veterinary Science
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• v.24 no.3
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• pp.43.1-43.8
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• 2023

Background: Meloxicam is used widely for exotic animal analgesia, but its toxicity in common raptor species in Thailand is unclear. Objectives: This study evaluated the single-dose effect of intramuscular meloxicam in common raptor species in Thailand for short-term and long-term periods. Methods: Twenty-two raptors were administered a single 1 mg/kg dose of meloxicam individually via intramuscular injection. The following were evaluated: clinical appearance, body weight, body condition score, body temperature, fecal appearance, complete blood cell count, and biochemistry panel before (day 0) and after the injection (1, 7, and 30 days). The collected samples were categorized into three groups: Brahminy kite (Haliastur indus) (n = 10), adult Barn owl (Tyto javanica) (n = 4), and juvenile Barn owl (n = 8). Results: None of the raptors in the study groups showed any abnormalities. The hematological profiles were significantly different in the short-term period (day 1 and day 7). The creatinine, aspartate aminotransferase, and creatinine kinase increased in several groups. On the other hand, the packed cell volume decreased in the Brahminy kite and juvenile Barn owl groups. According to the findings, an intramuscular injection of 1 mg/kg meloxicam affected the blood biochemistry panel of the muscle, but the affected raptors recovered within one week. Conclusions: An intramuscular injection of meloxicam at a single 1 mg/kg dose in Brahminy kites and Barn owls was not associated with the morbidity, hepatotoxicity, gastrointestinal toxicity, and nephrotoxicity in the short- and long-term periods.