• Selected Papers of The Society of Naval Architects of Korea
• /
• v.2 no.1
• /
• pp.63-78
• /
• 1994

This paper deals with the treatment of the open boundary in two-dimensional free-surface wave problems. Two numerical schemes are investigated for the implementation of the open boundary condition. One is to add the artificial damping term to the dynamic free-surface boundary condition, in which the determination of suitable damping coefficient and the damping zone is the most important. The other is a modified Orlanski's method, which is known to be very useful for the uni-directional waves. Using these two schemes, numerical tests have been conducted for a few typical free-surface wave problems. To obtain the numerical solution of the free-surface boundary value problem, the fundamental source-distribution method is used and the fully nonlinear free-surface boundary conditions are applied. The computed results are presented in comparison with those of others for the proof of practicality of these two schemes.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.151-157
• /
• 2005

In the chemical, mineral and electronics industries, mechanically stirred tanks are widely used for complex liquid and particle mixing processes. In order to understand the complex phenomena that occur in such tanks, it is necessary to investigate flow field in the vessel. Most difficulty on the numerical analysis of stirred tank flow field focused particularly on free surface analysis. In order to decrease the dead zone and improve the flow efficiency of a system with free surface, this paper presents a new method that overcomes free surface effects by properly combining the benefits of using experiment and 3-D CFD. This method is applied to study the mixing flow in an agitated tank. From the results of experimental studies using the PIV (particle image velocimetry) system, the distribution of mixing flow including free surface are obtained. And these values that are expressed as a velocity vector field have been patched for simulating the free surface. The results of velocity distribution obtained by 3-D CFD are compared with those of experimental results. The experimental data and the simulation results are in good agreement.

• Ocean Systems Engineering
• /
• v.1 no.1
• /
• pp.59-72
• /
• 2011

The objective of this work is to investigate the possibility of using the longitudinal strain on the surface of a pipe to determine the inception of dangerous free spanning. The long term objective is to develop an online monitoring technique to detect the development of dangerous free spanning in subsea pipelines. This work involves experimental study as well as finite element modeling. In the experiments, the strains at four points on a cross section of a pipeline inside the free span zone are measured. Pipes with different boundary conditions and different diameter to length ratios were tested. The pipe is treated as a simple beam with fixed-fixed or simply supported boundary conditions. The variation of the strains as a function of the diameter to length ratio gives a pointer to the inception of dangerous free spanning. The finite element results agree qualitatively with the experiments. The quantitative discrepancy is a result of the difficulty to replicate the exact boundary conditions that is used by the finite element program.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2002.10a
• /
• pp.27-29
• /
• 2002

• 산업보건소식
• /
• no.21
• /
• pp.18-24
• /
• 1985

A study on the hemoglobin and hematocrit concentrations of the lead exposed workers and organic solvent exposed workers in the Masan Free Export Zone

• Proceedings of the Korea Port Economic Association Conference
• /
• 2003.07a
• /
• pp.49-67
• /
• 2003

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.3
• /
• pp.45-55
• /
• 2020

Recently, as the awareness of fine dust has increased in Korea, various countermeasures have been suggested. This study examines the current status of fine dust free zones at home and abroad in order to analyze changes in guest space according to the occurrence of fine dust and to find activity patterns. I would like to predict and find implications. The purpose of this study is to forecast demand centering on domestic and foreign countermeasures for dust and domestic industry. In order to secure competitiveness for the smart city in the era of the 4th Industrial Revolution, the research is aimed at proposing a strategic plan to cope with the fine dust that is a threat to urban space. The research method is described in the following order.

• Journal of Navigation and Port Research
• /
• v.27 no.5
• /
• pp.563-568
• /
• 2003

Currently, the adoption of FTZ( Free Trade Zone) has been recognized as one of the most important strategies for becoming hub port in the world. For this reason, various policies for successful implementation and adoption of FTZ have been presented, and u special law related this FTZ was actually built in 1999. In the mean time, a port logistics industry is deeply related to the successful implementation of FTZ. However, although many research about FTZ have been conducted, there have been little previous studies about port logistics firms and FTZ. Thus, the aim of this study is to investigate a market structure of firms related to Port Logistics effectively and to analyze the perception of these firms about FTZ in Busan.

• Journal of Korean Neurosurgical Society
• /
• v.57 no.5
• /
• pp.350-358
• /
• 2015

Objective : To evaluate the morphometry of the anterior thalamoperforating arteries (ATPA). Methods : A microanatomical study was performed in 79 specimens from 42 formalin-fixed adult cadaver brains. The origins of the ATPAs were divided into anterior, middle, and posterior segments according to the crowding pattern. The morphometry of the ATPAs, including the premammillary artery (PMA), were examined under a surgical microscope. Results : The anterior and middle segments of the ATPAs arose at mean intervals of $1.75{\pm}1.62$ mm and $5.86{\pm}2.05$ mm from the internal carotid artery (ICA), and the interval between these segments was a mean of $3.17{\pm}1.64$ mm. The posterior segment arose at a mean interval of $2.43{\pm}1.46$ mm from the posterior cerebral artery (PCA), and the interval between the middle and posterior segments was a mean of $3.45{\pm}1.39$ mm. The mean numbers of perforators were $2.66{\pm}1.19$, $3.03{\pm}1.84$, and $1.67{\pm}0.98$ in the anterior, middle, and posterior segments, respectively. The PMA originated from the middle segment in 66% of cases. A perforator-free zone was located >2 mm from the ICA in 30.4% and >2 mm from the PCA in 67.1% of cases. Conclusion : Most perforators arose from the anterior and middle segments, within the anterior two-thirds of the posterior communicating artery (PCoA). The safest perforator-free zone was located closest to the PCA. These anatomical findings may be helpful to verify safety when treating lesions around the PCoA and in the interpeduncular fossa.

• Journal of Korea Port Economic Association
• /
• v.17 no.2
• /
• pp.183-204
• /
• 2001

This study is intended for the development of urgent facing strategies for the designation of a CFZ(Customs Free Zone) in Incheon city. First, it analyzes the current status of the Incheon CFZ. Next, it suggests several strategies for successfully growing the CFZ of Incheon City. Finally, it develops and proposes a method for establishing an integrated management system for the effective management of the CFZ. The key findings of this study are as follows: First, the CFZ should provide state-of-the-art movement of port logistics, create new added value caused by the movement of logistics, and provide other public support. The Incheon CFZ should be developed in three stages: an inducement stage in 2002-2005, a growth stage in 2005-2008, and an implementation stage in 2008-2011. Second, The parties responsible for the management of the CFZ would be as follows: for the port area, the Ministry of Maritime and Fisheries; for the back space of CFZ, Incheon City; and for port management, port management companies. However, a committee for CFZ management is strongly suggested for the improved efficiency and effectiveness of CFZ management. Furthermore, additional regulations ensuring the role of local government will likely be necessary for the sucessful designation and sustainable management of the CFZ. Third, For the creation of additional revenue, reformation of the current laws of the CFZ are recommended in the area of business administration. Fourth, A strategic marketing plan that supports the successful management of the companies of the CFZ will be a key component in the success of the CFZ. Thus, the new marketing plan should be developed in the near future based on case studies of other CFZs. Fifth A method for an integrated CFZ management system was developed and suggested for the comprehensive and transparent management of port logistics.