• Journal of Hydrospace Technology
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• v.2 no.2
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• pp.57-67
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• 1996

The formulation for hybrid-QUICK scheme of convective transport terms in finite-volume calculation procedure is presented. Source terms are modified to apply the hybrid-QUICK scheme. Test calculations are performed for wall-driven cavity flow at Re=$10_2$, $10_3$, and $10_4$. These include the evaluation of boundary conditions approximated by third-order finite difference scheme. The stable and converged solutions are obtained without unsteady terms in the momentum equations. The results using hybrid-QUICK scheme show no difference with those using hybrid scheme at low Re ($=10_2$) and are better at higher Re ($10_3$, and $10_4$).

• Journal of Korean Society of Transportation
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• v.35 no.3
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• pp.220-233
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• 2017

Traffic volumes are fundamental data widely used in various traffic analysis, such as origin-and-destination establishment, total traveled kilometer distance calculation, congestion evaluation, and so on. The low number of links collecting the traffic-volume data in a large urban highway network has weakened the quality of the analyses in practice. This study proposes a method to estimate the traffic volume data on a highway link where no collection device is available by introducing a spatial statistic technique with (1) the traffic-volume data from TOPIS, and National Transport Information Center in the Ministry of Land, Infrastructure, and (2) the navigation data from private navigation. Two different component models were prepared for the interrupted and the uninterrupted flows respectively, due to their different traffic-flow characteristics: the piecewise constant function and the regression kriging. The comparison of the traffic volumes estimated by the proposed method against the ones counted in the field showed that the level of error includes 6.26% in MAPE and 5,410 in RMSE, and thus the prediction error is 20.3% in MAPE.

• 한국해양학회지
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• v.17 no.1
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• pp.12-18
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• 1982

Tidal exchanges of sea water are studied by using drogue experiments and tidal current measurement data in Gamag Bay which has two channels. At the spring tide, the volume of tidal transport in the bay was estimated to be 46∼52% of the total volume of sea water in Gamag Bay, 7.1 10$\^$8/㎥. The tidal transport through the wide channel occupies 87% of the total tide transport of the bay. Residual current was deduced to flow north-northeastward at the rate of 3.254 10$\^$5/㎥ per tidal cycle. the tidal exchange of the sea water during the flood flow was estimated to be approximately 26% of the tidal transport, while that during the ebb flow was 41%. The tidal exchange through the wide channel during the flood flow occupies 77% of total tidal exchange of the bay through both channels, whereas that during the ebb flow does 88%. The diffusion coefficient of 2.08∼ 2.30 10$\^$7/$\textrm{cm}^2$/sec at the narrow channel was greater than that at the wide channel which was 1.2∼2.8 10$\^$6/$\textrm{cm}^2$/sec.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.2
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• pp.73-81
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• 2004

Voltage induced by the Tsushima Current on an abandoned submarine telephone cable has been measured since March 1998 in order to monitor the volume transport through the Korea Strait. Voltage has a good linear relationship with the transport measured by bottom-mounted Acoustic Doppler Current Profilers (ADCPs) along a section spanning the Korea Strait. This paper reviews researches using submarine cables briefly; we introduce the method to measure voltage on submarine cables, present some results focusing on the example of the Korea Strait, and mention the future prospect to use other submarine cables around Korea.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.21-36
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• 2015

These days Automated Vehicle(AV) has been receiving attention as a fundamental solution to resolve the various transportation problems and various researches related to the benefits of AV have been done. However, previous researches mainly analyzed the effects in the virtual network. The purpose of this research is to predict and to find out the benefits by introducing the Automated Vehicle to present road traffic system. Thus, the study analyzes the traffic-flow changes of Gyeongbu freeway Seoul-Singal basic section which is planned for setting the test-bed. The results show that Automated Vehicle can have negative effects on the traffic-flow in low volume of LOS A and B. However, the average speed increases and the traffic density decreases in more than LOS C, the traffic volume increase. Therefore, the introduction of Automated Vehicle achieves positive effect on various transportation problems such as the traffic congestion.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.5
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• pp.405-414
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• 2015

Fluid transport is a key issue in the development of microfluidic systems. Recently, Myong (2014) has proposed a new concept for droplet transport without external power sources and numerically validated the results for a hypothetical 2D, initially having a hemicylindrical droplet. In this paper, the movement of an actual water droplet, initially having a 3D hemispherical shape, on horizontal hydrophilic/hydrophobic surfaces is simulated using a commercial computational fluid dynamics (CFD) package, Fluent, with VOF (volume of fluid) method. The results are compared with the 2D analysis of Myong (2014), and the transport mechanism for the actual water droplet is examined based on the numerical results of the time evolution of the droplet shape, as well as the total kinetic, gravitational, surface free and pressure energies inside the droplet.

• Journal of Korea Water Resources Association
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• v.47 no.11
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• pp.1061-1066
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• 2014

A stable second-order finite volume method was proposed to predict sediment transport under rapidly varied flow conditions such as transcritical flow. For the use under unsteady flow conditions, a sediment transport model was coupled with shallow water equations. HLLC approximate Riemann solver based on a monotone upstream-centered schemes for conservation laws (MUSCL) reconstruction was used for the computation of the flux terms. From the comparisons of dam break flow experiments on erodible beds in one- and two-dimensional channels, good agreements were obtained when proper parameters were provided. Lastly, dam surface erosion problem by overtopped water was simulated. Overall, the numerical solutions showed reasonable results, which demonstrated that the proposed numerical scheme could provide stable and physical results in the cases of subcritical and supercritical flow conditions.

• Korean Journal of Veterinary Service
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• v.26 no.2
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• pp.185-191
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• 2003

There was a mass outbreak of death caused by transport stress and malnutrition in Japanese macaques imported from Japan at a farm stock in Korea, which were diagnosed on the ground of history taking, clinical finding, hematological examination and necropsy. Twenty eight Japanese macaques imported from Japan died suddenly from the 4th day after arrival in a farm. These animals were confined very small cages individually and lose the appetite for 10 days from shipping. Main clinical findings observed from alive Japanese macaques consisted of hypothermia and dehydration. On hematological observation for typical 4 cases showed increased erythrocytes and packed cell volume. On serum biochemical examination for 3 cases showed hypoglycemia, whereas blood urea nitrogen, aspartate aminotransferase and alanine aminotransferase were increased. On necropsy for 3 cases, hemorrhage and congestion were observed on the lung and the walls of stomach and intestine were thinned. Histologically, hemorrhagic pneumonia and enteritis with loss of villi were seen. The death of these animal was caused by poor management during transport, which was resulted in transport stress and malnutrition.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2359-2373
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• 2008

In 1991, Korean government decided to establish the Inland Container Depot for activating transportation of rail freight container and encourage the effectiveness of intermodal transport system. Therefore, the Ui-Wang ICD has been built in Kyonggi province and began to operate in 1993. However, Despite of original purpose of the Inland Container Depot, rail freight volume at public CY(Container Yard) in Ui-Wang ICD has been recorded very low. This paper deals with the promotion strategy for rail transport in Ui-Wang ICD. The relationship of conflicts between the rail-oriented transporters and road-oriented transporters in Ui-Wang ICD have been found through the TOC thinking process and some solutions are suggested. Some undesirable effects in operation of Ui-Wang ICD are listed and current reality tree(CRT) has been established and future reality tree(FRT) which includes some injections to active the rail transport in ICD has been recommended based on CRT. In order to make good solutions the situation in Busan-jin station ICD known as similar to Ui-Wang ICD has been analyzed.

• Journal of Korea Port Economic Association
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• v.23 no.2
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• pp.25-40
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• 2007

The sea/air intermodal transport is a time-saving and cost-saving transport for cargo shipments. In reaction to a recent growth of high value-added products in China, the volume of sea/air intermodal transport in Korean airport has been increasing continuously. This paper treats the situation, the system, and the possibility of sea/air intermodal transport, which are emerging as an alternative to solve the logistics problem related to the increase of international air cargo demand in China. Also, several strategies are considered to develope Korea into intermodal transport hub including the value added logistics activity which will secure the demand of sea/air intermodal transport.