• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 1998년도 추계학술대회논문집:21세기에 대비한 지능형 통합항만관리
• /
• pp.51-58
• /
• 1998

This study is to define the Automated Container Terminal(ACT) and container terminal system. Also, we analyze the present condition of the container terminal system in Pusan port and its automation level by systems approach. And this paper aims at evaluating on the priority of R&D investment until the beginning of the second stage of New Pusan Port Project(2006). In this process we have considered 8 factors (cost, labor, area, time volume, reliability, safety, convenience) to analyze 6 subsystems. The priority order of R&D until target year by sub-systems is as follow : Cargo Handling System〉Transfer System〉Port Entry System〉Storage System(Distribution&Manufacturing System included)〉Inland Transport System〉Port Information System.

• 한국세라믹학회지
• /
• 제47권1호
• /
• pp.8-18
• /
• 2010

When metal oxides are exposed to chemical potential gradients, ions are driven to diffusive mass transport. During this transport process, the divergence of ionic fluxes offers the formation/annihilation of oxides. Therefore, the divergence of ionic flux may play an important role in the void formation in oxides. Kinetic equations were derived for describing chemical potential distribution, ionic fluxes and their divergence in oxides. The divergence was found to be the measure of void formation. Defect chemistry in scales is directly related to the sign of divergence and gives an indication of the void formation behavior. The quantitative estimation on the void formation was successfully applied to a growing magnetite scale in high temperature oxidation of iron at 823 K.

• 대한기계학회논문집B
• /
• 제20권10호
• /
• pp.3282-3292
• /
• 1996

Flow velocity was measured using a hot wire anemometer. Turbulence intensity was in proportion to mean flow velocity regardless of swirl velocity. And integral length scale has proportional relation with swirl velocity regardless of measurement position. Flame speed calculated by radius of visualized flame was increased and then decreased according to lapse of time from spark. Maximum flame speed was increased according to increase of turbulence intensity. Burning speed and flame transport effect increased with increase of swirl velocity, but ratio of burning speed to flame speed decreased with increased of swirl velocity. Mass fraction burned versus volume fraction burned was increased in proportion to the increase of turbulence intensity, caused by increase of combustion promotion effect according to increase of turbulence intensity and scale.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2002년도 학술대회지
• /
• pp.329-332
• /
• 2002

A theoretical study is made of the steady flow of a compressible fluid in a rapidly rotating finite cylinder. Flow is generated by imposing mechanical and/or thermal disturbances at the rotating endwall disks. Both the Ekman and Rossby numbers are small. A detailed consideration is given to the energy budget for a control volume in the Ekman boundary layer. A combination of physical variables, which is termed the energy contents, consisting of temperature and modified angular momentum, emerges to be relevant. The distinguishing features of a compressible fluid, in contrast to those of an incompressible fluid, are noted. For the Taylor-Proudman column to be sustained, in the interior, it is shown that the net energy transport between the solid disk wall and the interior fluid should vanish. Physical rationalizations are facilitated by resorting to the concept of the afore-stated energy content.

• Journal of Mechanical Science and Technology
• /
• 제16권5호
• /
• pp.676-682
• /
• 2002

The laminar convective heat transfer in ventilated space with various horizontal partitions was studied numerically and experimentally For the numerical study, the governing equations were solved by using a finite volume method for various numbers Re, Gr, Pr and partition numbers. The experimental study was conducted by using a holographic interferometer. The isotherms and velocity vectors have been presented for various parameters. As the number and length of partition increased, convective heat transfer decreased. Based on the numerical data, correlation equations were obtained for the mean Nusselt number in term of Gr/Re$^2$. In the region of Gr/Re$^2$$\leq$ 1, the mean Nusselt number was small, but in the region of Gr/Re$^2$> 1, the mean Nusselt number was constant.

• 전자공학회지
• /
• 제24권2호
• /
• pp.13-26
• /
• 1997

Throughout the world in major urban centers, the volume of vehicular traffic on roads continues to increase. ITS provides drivers with traffic information and new routing options on route In order to make them move quickly to their destinations. The higher mobility, the more productivity we gain. The ultimate goal of Intelligent Transport System is to improve mobility. ITS world is broad and quite varied, as demonstrated by ITS user services, their distinct needs, and complex Interactions and synergies. ITS ties the transportation and telecommunication worlds together. The complex world of telecommunications is evolving and expanding rapidly. Especially over the last two decades, the birth and unprecedented growth of wireless is really marvelous and further holds tremendous promise into the future. This wireless and emerging technologies will offer extensive opportunities to handle many ITS user services, and alter many of the traditional paradigms of transportation.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2005년도 춘계학술대회 논문집
• /
• pp.985-990
• /
• 2005

The success of road transportation, in dominating the surface movement of freight, is now threatened by increased traffic congestion, falling average motorway speed and rising in logistics costs, oil price. Due to the necessity for an effective transport system, we need to improve domestic transport infrastructure to reduce logistics cost by shifting to rail system. To analysis the demand characteristics in advance against these hypothetical circumstances, Stated Preference, which is called SP, approaches have been adopted to analysis the shipper's mode choice behaviors as RP(Revealed Preference) approaches are not appropriate. The results also indicate that the most effective policy to divert the freight volume from road to railway is to reduce freight rates for the railway with improved reliability.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2007년도 추계학술대회 논문집
• /
• pp.23-26
• /
• 2007

Liquid water in flow channel is an important factor that limits the steady and transient performance of PEM fuel cells. A computational fluid dynamics study based on the volume-of-fluid (VOF) multi-phase model is conducted to understand the transport behavior of liquid water in flow channel. The liquid water transport in $180^{\circ}$ bends is investigated and the effect of chamfering is discussed. The effect of wall adhesion is also considered by varying the contact angle of channel surfaces. The result of this study is believed to provide a useful guideline for design optimization of flow patterns or channel configurations of PEM fuel cells.

• International Journal of Vascular Biomedical Engineering
• /
• 제4권2호
• /
• pp.13-18
• /
• 2006

Direct injection of a fibrinolytic agent to the intra-arterial thrombosis may increase the effectiveness of thrombolysis by enhancing the permeation of thrombolytic agents into the blood clot. Permeation of fibrinolytic agents into a clot is influenced by the surface pressure, which is determined by the injection velocity of fibrinolytic agents. Computational fluid dynamic methods were used in order to predict clot lysis for different jet velocities and nozzle arrangements. Firstly, thrombolysis of a clot was mathematically modeled based on the pressure and lysis front velocity relationship. Direct injection of a thrombolytic agent increased the speed of thrombolysis significantly and the effectiveness was increased as the ejecting velocity increased. The nine nozzles model showed about 20% increase of the lysed volume, and the one and seventeen nozzles models did not show significant differences. Secondly, thrombolysis was modeled based on the enzyme transport and the fluid flow equations, and quasi steady numerical analysis was performed. Clot lysis efficiency was also increased as injection velocity increased.

• 한국연소학회지
• /
• 제14권2호
• /
• pp.32-41
• /
• 2009

The transported probability density function model combined with the consistent finite volume (FV) method has been applied to simulate the turbulent bluff-body reacting flows. To realistically account for the non-isotropic turbulence effects on the turbulent bluff-body reacting flows, the present PDF transport approach is based on the joint velocity- turbulent frequency-composition PDF formulation. The evolution of the fluctuating velocity of a particle is modeled by a simplified Langevin equation and the particle turbulence frequency is represented by the modified Jayesh - Pope model. Effects of molecular diffusion are represented by the interaction by exchange with the mean (IEM) mixing model. To validate this hybrid FV/PDF transport model, the numerical results are compared with experimental data for the turbulent bluff-body reacting flows.