• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.3
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• pp.263-270
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• 2016

This study is aimed to design the mechanical gascyclone precipitator with an outstanding collection efficiency as one of ways to reduce exhaust gas of small-scale vessels. It estimated fine particles generated from diesel engines which has become one of the biggest environmental issues currently. Specifically, it quantitatively analyzed the flowing process from the cyclone gas exit; a duct via part to the collecting part of Cylindrical lower using DPIV (Digital Particle Image Velocimetry). Since the gas inlet height part became wider the previous theoretical dimensions, internal fluid characteristics of cyclone where the speed of internal swirl had been slow were investigated by temporary streamline of fine particles at $14-20{\mu}m$. The results showed that collecting efficiency was three times higher than the conical type utilized previously. In addition, this study supplemented imprecision problems from the previous theoretical equation and CFD interpretation with an experimental method. It also provided a basic data to design the cyclone precipitator by size of diesel engines for vessels.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.716-724
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• 1990

Oblique impinging plane jets were investigated experimentally and numerically at Reynolds number 21000. The inclination angle was varied from 90.deg.(normal to the impinging plate) to 60.deg.. The distance H between the nozzle exit and the stagnation point on the impinging plate was fixed at H/D=8. The working fluid was air. The mean velocity components and turbulent quantities were measured by a hot-wire anemometer. And the static pressure distributions on the impinging plate were measured by a Pitot tube. In numerical computation, the governing partial differential equations of elliptic type were solved with conventional k-.epsilon. turbulence model. The measurements show that, after impingement, the jet half width alone the wall increases in both directions, and that similarity for each turbulent quantity such as Reynolds shear stress or turbulent kinetic energy is revealed in the wall jet region. The computed results show some deviation from experimental data in the impingement region, where streamline curvature is significant. However, the computed results agree qualitatively well with measurements.

• Bulletin of the Society of Naval Architects of Korea
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• v.10 no.2
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• pp.19-28
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• 1973

This paper deals with a problem for determining the bulbous bow ship from which pertains to the study of the theoretical ship form planing method. In this paper has been determined the bulbous bow ship form which is a similar in geometric particulars with the conventional liner ship G.T.10, 000 by adopting the variable method for finding the optimum ship form by A.Y.C. Lee and the streamline tracing method by T. Inui and P.C. Pien. Each resistance performance is examined by the towing test and is compared with one another. The followings are the outcome of this study: Among the 5 type models, the bulbous bow ship form M.S. B 1120 is the most excellent for the resistance performance. The effect for the wave resistance is very sharp according to the difference of the bottom flattening of theoretical ship form. The optimum value of the bulbous bow for wave resistance can be obtained by the variable method mentioned above, and for the series of(Main hull+Bulb)opt., ${\alpha}=75/25$, the value is $f{\approx}0.11$.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.10
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• pp.754-760
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• 2008

Computation of moving interface by the level set method typically requires the reinitialization of level set function. An inaccurate estimation of level set function $\phi$ results in incorrect free-surface capturing and thus errors such as mass gain/loss. Therefore, an accurate and robust reinitialization process is essential to the simulation of free-surface flows. In the present paper, we pursue further development of the reinitialization process, which evaluates level set function directly using a normal vector on the interface without solving there-distancing equation of hyperbolic type. The Taylor-Galerkin approximation and P1P1 splitting/SUPG (Streamline Upwind Petrov-Galerkin) FEM are adopted to discretize advection equation of the level set function and the incompressible Navier-Stokes equation, respectively. Advection equation and re-initialization process of free surface capturing are validated with benchmark problems, i.e., a broken dam flow and timereversed single vortex flow. The simulation results are in good agreement with the existing results.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.3 no.4
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• pp.241-249
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• 1991

A quasi-three dimensional calculation method is presented on the basis of Wu's idea using finite element methods. In B-B flow the governing equations are cast into a single equation to overcome the restriction of the type of turbomachinery, and Kutta condition is exactly assured by introducing a combination of two kinds of stream functions. In H-S flow a dissipative force which is assumed to be opposed to the relative velocity is added to the governing equation for a consistent loss model. The entropy change along each streamline is then calculated by assuming that the dissipative force may be a force coming from laminar viscous stresses with inviscid velocity distributions. Both the flow solvers are combined to build a three-dimensional flow field through a few iterations. For an effect of the distortion of H-S flow surface the body forces are computed after each B-B flow calculation is finished. Mizuki's centrifugal impellers are tested numerically. The reliability of the numerical solution compared with experimental data is guaranteed.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.3
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• pp.452-473
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• 2018

This study analyzed the expressions of racing girl uniforms that promote automobile brands shown at Seoul and Busan motor shows. The results are as follows. In each of the design components expression, the glossy and plain material, the achromatic color, and the dress style appeared most frequently in the uniform design of both domestic and foreign automobile brands. In the fashion image expression, sexy image appeared the most, followed by modern image, romantic image, active image, elegance image and ethnic image. Based on the analysis results, the following expressive characteristics were identified: First, sexy images were used in uniform design to express the streamline and speedy feeling of a car metaphorically. Second, modern image, glossy material, and achromatic color were used for a uniform design to express advanced technology and the future orientation of an automobile. Third, fashion images that match the automobile type emphasized the brand image of the car. Fourth, some of the manufacturers that prevailed in the automobile market promoted several automobile brands exhibited with a unified uniform design that expressed the design philosophy and concept. As such, the motor show racing girl uniform contributed to promoting automobile brand identity and the automobile industry.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.15-20
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• 2008

Contaminated sediments are the actual cause for deterioration of coastal-ecosystem. So the developed countries have been in the process of making an effort to develop new techniques for monitoring and solving this problem since 1960. In this research, suction type pump dredging system of pilot size for collecting the filth from the seabed has been designed and manufactured that can prevent or minimize the secondary pollution by filth diffusion. For the practical use, the application possibility of the developed system has been checked through a system performance test. And, the evaluation of system performance according to the underwater body type has been carried out for system optimization by using CFD. The performance tests for checking the efficiency of sediment collecting system are done under two conditions i.e. when the system is non-operational and when the system is self-propelled. The results of this research showed the possibility of the development of dredging system to remove just the upper parts of filth from seabed.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.880-885
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• 2007

In the last decades, the resource used in the construction process has become much more various in kinds and increased in number as construction has become enlargement and complexity. Resource management on a construction site has been recognized as a detrimental factor to influence project success, therefore various technologies have been applied by the construction industry to streamline resource management. RFID/USN interworking system composed of RFID technology and sensor network supports automation of resource management and real-time information networking. Most of research efforts for RFID technology in the construction industry have been limited to object identification technology. The study proposed herein it to verify the applicability of RFID/USN interworking system to the construction industry. The identification rates of RFID/USN interworking system by distance and degree and by type of materials was identified and analyzed.

• Women's Health Nursing
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• v.27 no.2
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• pp.75-92
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• 2021

Purpose: This study aimed to analyze the content and effectiveness of psychosocial support interventions for women with gestational diabetes mellitus (GDM). Methods: The following databases were searched with no limitation of the time period: Ovid-MEDLINE, Cochrane Library, Ovid-Embase, CINAHL, PsycINFO, NDSL, KoreaMed, RISS, and KISS. Two investigators independently reviewed and selected articles according to the predefined inclusion/exclusion criteria. ROB 2.0 and the RoBANS 2.0 checklist were used to evaluate study quality. Results: Based on the 14 selected studies, psychosocial support interventions were provided for the purpose of (1) informational support (including GDM and diabetes mellitus information; how to manage diet, exercise, stress, blood glucose, and weight; postpartum management; and prevention of type 2 diabetes mellitus); (2) self-management motivation (setting goals for diet and exercise management, glucose monitoring, and enhancing positive health behaviors); (3) relaxation (practicing breathing and/or meditation); and (4) emotional support (sharing opinions and support). Psychosocial supportive interventions to women with GDM lead to behavioral change, mostly in the form of self-care behavior; they also reduce depression, anxiety and stress, and have an impact on improving self-efficacy. These interventions contribute to lowering physiological parameters such as fasting plasma glucose, glycated hemoglobin, and 2-hour postprandial glucose levels. Conclusion: Psychosocial supportive interventions can indeed positively affect self-care behaviors, lifestyle changes, and physiological parameters in women with GDM. Nurses can play a pivotal role in integrative management and can streamline the care for women with GDM during pregnancy and following birth, especially through psychosocial support interventions.

• Journal of Practical Engineering Education
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• v.15 no.3
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• pp.771-777
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• 2023

The study was conducted on accounting information system education and utilization in korea's fishing industry. The Korean fishery industry is having difficulty in management due to inefficient management of companies, a decrease in the number of employees, the aging of workers, and cheap imported seafood. In such an environment, the paper looks for a plan to streamline management using fisheries accounting. To this end, an accounting-related survey was conducted on fisheries companies. The suggestions for the analysis results are as follows. First, the management of the fisheries industry in today's information age needs to use efficient management techniques through accounting. Second, fisheries companies need to increase efficiency by actively introducing accounting into management and utilizing the operation and procurement of funds, cost management and management analysis. Third, it is time for fisheries companies to calculate costs by using accounting management and utilize them for rational decisionmaking. Finally, seafood is the most important type of food. Therefore, the growth of fisheries companies needs to be recognized as an essential task. From this point of view, fisheries accounting is a way to generate profits through management efficiency.