• Journal of Power System Engineering
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• v.10 no.3
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• pp.88-96
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• 2006

While the crane system operate in port, one of main objective is to transport containers to the goal position as soon as possible. Because this is one of the biggest problem in terms of productivity of port, the container crane is operated by an expert operator until now. However recently an automatic control system with high performance is required to improve the performance of the crane system and to make high productivity. Therefore we developed an optimal controller based on Humoral Immune Algorithm with PID controller. The proposed system has a real time structure and can improve the performance such as anti-sway problem. Some computer simulations are implemented to assess the characteristics of the proposed controller.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10c
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• pp.424-426
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• 2001

현재의 인터넷 응용들을 살펴보면 종 단간 혼잡 제어 방법을 지원하는 TCP를 대표적인 전송 프로토콜로 사용하고 있음을 알 수 있다. 그러나 최근 폭발적으로 증가하는 멀티미디어 서비스들은 UDP 혹은 보다 적절한 RTP(Real-time Transport Protoco) 와 같은 미디어의 실시간 특성에 맞는 전송 프로토콜을 주로 사용하고 있다. 그런대 TCP-friendly 하지 않는 UDP나 RTP 같은 트래픽의 무분별한 증가는 같은 링크를 점유하며 공정하게 경쟁하는 TCP 연결들의 전송 효율을 억제 하는 특성을 나타낸다. 그러므로 이러한 현상은 네트워크 활용에 불균형 현상을 초래 한다. 본 논문에서는 이러한 문제를 해결 하기위해서 TCP-Friendly 멀티미디어 전송 프로토콜인 SRTP(Smart RTP)를 제안하였다. 또한 구현 및 성능평가를 통해서 이 프로토콜이 스트리밍 전송률을 동적으로 순화하면서 혼잡 상황에 적절히 적응 할 수 있음을 나타내었다.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.293-295
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• 2009

In an Intelligent Transport System(ITS), data dissemination based on inter-vehicle communication is effective for acquiring real-time traffic-jam information. In this paper, we propose a novel method for traffic jam information dissemination in vehicular ad-hoc networks. In our proposed method, vehicles already trapped in a Traffic-Jam elect leaders according to their locations from upstream and downstream respectively. Then each leader generates traffic data which contains their position, velocity and leader counter respectively, and disseminate the information. {{br}}The implementation of our proposed method is evaluated by means of simulation, and we also present simulation result

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.625-626
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• 2008

Today, the railway is very important in modern society means of public transport. Many people use the railway each day. On the other hand, with regard to railway accidents every year due to damage caused many casualties. In this paper, we propose railroad crossing accident prevention system for monitoring the situation based on OSGi for safe railway operations, about the same railroad crossing a dangerous place. This system, communication between the train and railroad crossing. So the information from the train crossing while a train driver was monitored in real time with more information than can help prevent accidents on the crossing. Using the OSGi framework, can be used widely in many hardware.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.423-428
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• 1995

Simulation models have been developed to predict the overall behavior of the CANDU plant systems during normal operational transients. For real time simulation purpose, simplified thermal hydraulic models are applied with appropriate system control logics, which include primary heat transport system solver with its component models and secondary side system models. The secondary side models are mainly used to provide boundary conditions for primary system calculation and to accomodate plant power control logics. Also, for the effective use of simulation package, hardware oriented basic simulation network has been established with appropriate graphic display system. Through validation with typical plant power maneuvering cases using proven plant performance analysis computer code, the present simulation package shows reasonable capability in the prediction of the dynamic behavior of plant variables during operational transients of CANDU plant, which means that this simulation tool can be utilized as a basic framework for full scope simulation network through further improvements.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1072-1080
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• 2000

Leakage magnetic flux (LMF) is widely used for non-contact detection of cracks. The combination of optics and LMF offers advantages such as real time inspection, elimination of electrical noise, high spatial resolution, etc. This paper describes a new nondestructive evaluation method based on an original magneto-optical inspection system, which uses a magneto-optical sensor, LMF, and an improved magnetization method. The improved magnetization method has the following characteristics: high observation sensitivity, independence of the crack orientation, and precise transcription of the geometry of a complex crack. The use of vertical magnetization enables the visualization of the length and width of a crack. The inspection system provides the images of the crack, and shows a possibility for the computation of its depth.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.1
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• pp.173-183
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• 2011

Global logistics including Korea had developed at various fields through the developed IT technology. In addition, in changing into Internet based digital economy times, economic and logistics activities became extending into worldwide over the cross-border. Logistics activity performed by off-line rapidly changed in real environment. But, unfortunately business process modeling about the whole logistics was not happened, even though process modeling had done by transport stages or logistics entities. Therefore, it is difficult to grasp the whole logistics. Additional cost and time was requested due to no association between logistics entities and invisibility. So, this paper has to be process modeling for logistics industry domain. For objective modeling, work area shall be divided and it extracts general work process per each area. And then it defines subprocess of general work process. Cargo tracking in logistics industry domain means to grasp the status and present states at transportation or storage stage. This paper defines business process and data model for electronic processed work area using the UN/CEFACT standard modeling methodology.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.12 no.2
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• pp.43-58
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• 2004

Up-to-date cargo transport system, CVO(Commercial Vehicle Operations) is the system to manage efficiently cargo distribution as providing at real time the information of cargo location and situation through ITS and GPS technology. In this paper, we proposed the Gate Automation System of harbors among AEI/AVI. To implement his system, we use the DSRC/RFID(Dedicated Short Range Communication / Radio Frequency IDentification) which adopts an wireless communication between RSE(Road-side Equipment) and OBE(on-Board Equipment) on a vehicle. When constructing the Gate automation system of harbors, the business application ability are reviewed practically and the logistics facilities to be constructed in the near future may use this project results according to the international standard and it could help complete integrated logistics system.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.349-354
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• 2004

A monitoring system for container is the positioning and managing system, which has been rapidly updated recently, for logistics in real-time. GPS is a global positioning system which is capable of positioning container promptly with a reasonable amount of accuracy. Facility managers of ports or airports should load/unload/keep freight effectively. Transport companies or freight owners should allocate moving container properly and be able to prevent or cope with the loss or delay of freight. In this study, it is monitored and tested the movement of the containers fitted with GPS, and its accuracy and efficiency is analyzed.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.E
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• pp.347-357
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• 1993

The Lagrangian grid-free numerical method, the discrete vortex method, was applied to solve the Navier-Stokes euqations. This method avoids the introduction of numerical viscosity swamping the real physical viscosity at high Reynolds number, unlike Eulerian method, e.g. finite difference and element methods. The boundary integral equation method for the potential flow solution was included to make the discrete vortex method more feasible for complex geometries. The fast adaptive multipole expansion method was incorporated to reduce the computational time from $O(N^2)$ to O(N) for the computations of vortex-vortex interactions. The test problems were air flow around one circular cylinder and two circular cylinders in tandem with various gaps. The numerical results were in excellent gareement with the experimental and other computational results. The applicabilty of the method was discussed with the indoor and the outdoor air pollution problems, especially the contaminant transport in the recirculation regions.