• Journal of Navigation and Port Research
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• v.31 no.8
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• pp.717-723
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• 2007

In recent years, the transportation sector has been undergoing very rapid and multifarious changes due to the M&A, alliances between shipping companies, introduction of larger container ship as it cost reduction measure and the application of integrated logistics to satisfy the needs of customers. Therefore, container terminal is required adequate terminal facilities, sufficient channel depth, efficient handling and low cost of port fees and dues. The purpose of this paper is for functional assessment of efficient container terminal. Firstly, the container operating process information about yard equipment and chassis is extracted through the analysis of practical daily work report of container terminal. Also, the formulae of skill factor and troubles of operator on transfer crane are defined. Lastly, container handling simulation model which consideration of skill factor and trouble of operator is proposed by Petri network model.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.2940-2947
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• 2000

In the wireless ATM networks, a Medium Access Control (MAC) protocol is required to support an integrated mix of multimedia traffic services. The MAC protocol should be designed in a way that the limited wireless bandwidth can be efficiently utilized maximizing the Quality of Service (QoS) guarantees for various traffic service classes. In this paper, a Dynamic Resource Allocation-based MAC protocol, which satisfies QoS of each traffic service class in the wireless ATM environment, is proposed. The proposed MAC protocol adopts the dynamic channel allocation schemes for a mix of different traffic service classes. The suggested MAC protocol is designed to provide the QoS guarantees for Constant Bit Rate (CBR) or real-time Variable Bit Rate (VBR) traffic through fixed or dynamic reservation. For Available Bit Rate (ABH) traffic, which has the lowest priority among the traffic classes, large improvement in delay by reserving the minimum bandwidth is shown. And for real-time VBR traffic, increase in throughput of transmission is demonstrated because of bandwidth, which is allocated through contention at the initial phase and without contention thereafter.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.29-34
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• 2008

We fabricated the 4 channel wave function generator with variable frequency, pulse width, amplitude and rising/falling slope to develop driving method of charged particle type display. The selective sell driving is ascertained by fabricated panel with black and yellow particles. To measure CIE point, reflectivity, contrast ratio and viewing angle, experimental apparatus is integrated with optical circular$(1^{\circ})$ moving emitting/receiving part and spectrometer connected to emitting part. The yellow particles in glass have reflectivity of $35{\sim}40%$ and wavelength of 571.2nm and black one has reflectivity of $15{\sim}20%$ in case of only 1 layer of particle, and the case of 3 layer the optical property is promoted.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.4
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• pp.117-127
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• 1992

Japan is situated in the zone attacked repeatedly by typhoon. She is apt to be given by the nature damage like flood and loss the life and the property conventionally because of her short channel and steep slope ground. This paper is centered on the method of analysis and the damage management of river which are based on the Bulletin of the Disaster Prevention Research Institute of Kyoto University. The field of flood disaster, submersion damage, water proof system, debris control disaster and water resources are studied respectely. The river management examples which are done by Foundation of River and Basin Integrated Communications and The Yodo River are analyzed. The above analysis helps to control disaster of river in Korea.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.8
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• pp.1456-1463
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• 2010

The safety critical systems in nuclear power plants should be designed to have a high level of fault tolerant capability because those systems are used for protection or mitigation of the postulated accidents of nuclear reactor. Due to increasing of the system complexity of the digital based system in nuclear fields, the reliability of the digital based systems without an auto-test or a self-diagnostic feature is generally lower than those of analog system. To overcome this problem, additional redundant architectures in each redundant channel and self-diagnostic features are commonly integrated into the digital safety systems. The self diagnostic function is a key factor for increasing fault tolerant capabilities in the digital based safety system. This paper presents an availability and safety evaluation model to analyze the effect to the system's fault tolerant capabilities depending on self-diagnostic features when the loss or erroneous behaviors of self-diagnostic function are expected to occur. The analysis result of the proposed model on the several modules of a safety platform shows that the improvement effect on unavailability of each module has generally become smaller than the result of usage of conventional models and the unavailability itself has changed significantly depending on the characteristics of failures or errors of self-diagnostic function.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.4
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• pp.425-430
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• 2013

Robust and high speed underwater communication is severely limited when compared to communications in terrestial. In free space, RF communication operates over long distances at high data rates. However, the obstacle in seawater is the severe attenuation due to the conducting nature. Acoustic modems are capable of long range communication up to several tens of kilometers, but it has low data-rate, high power consumption and low propagation speed. An alternative means of underwater communication is based on optics, wherein high data rates are possible. In this paper, the characteristics of underwater channel in the range of visible wavelength is investigated. And the possibility of optical wireless communication in underwater is also described. The LED-based transceiver and CMOS sensor module are integrated in the system, and the performance of image transmission was demonstrated.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.467-470
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• 2006

For a mobile application such as cellular phone, micro fuel cells should be extremely compact and thin. RHFC can be an alternative solution because RHFC gives higher power density than DMFC and does not need ahydrogen storage vessel In this paper, RHFC using methanol fuel is made as a novel planar design without a PROX. Both reformer and cell are made closely in a same plate to share the heater of reformer with the cell. The PBI membrane is used in the cell. The reason is that high temperature of reformer can cause a performance drop when perfluorosulfonic acid membrane such as Nafion is used such a high temperature operation also guarantees the higher CO tolerance to MEA catalyst. The cell is designed as an air-breathing type which the cathode of the cell is opened to the air. The commercial Cu/ZnO/Al2O3 steam reformer catalyst is packed in reformer channel. The active area of MEA is $11.9cm^2$ and the peak power density was $27.5mW/cm^2$.

• Journal of Korea Water Resources Association
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• v.38 no.4 s.153
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• pp.259-269
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• 2005

One- and two-dimensional coupling model has been developed to analyze the flood inundation aspect of protected lowland. One-dimensional model solves the Saint-Venant equations by the Preissmann method, and two-dimensional model solves the shallow water equation by the integrated finite difference method. The coupling model approximates unsteady supercritical and subcritical flow, backwater flooding effects, and escaping and returning flow from two-dimensional flow model to channel system. The model has been applied to the levee failure in the Nakdong river during September 13 through 15, 2000. Velocity distributions and inundated depths were presented to demonstrate model simulation results.

• Journal of Satellite, Information and Communications
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• v.10 no.3
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• pp.102-108
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• 2015

With the constantly increasing demand of domestic and oversea satellite images, there is also a growing demand to rapidly acquire images after the satellite image collection planning of KOMPSAT-2/3/5. Therefore, it has been increasing to use the korea ground station and oversea ground station to keep pace with increased demand. The KARI is operating Data Ingestion System of the KOMPSAT-2/3 in Svalbard, where the satellite images have been received at least four or six times a day. The KARI is planning to operate oversea receiving system for KOMPSAT-5/3A. This paper introduces the polar data ingestion system operating in Norway, and presents the process of design and development for Polar Integration receiving system in preparation of multiple satellite operation.

• Journal of Korean Library and Information Science Society
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• v.8
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• pp.97-126
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• 1981

The professional duties of librarians and other information workers involve a generalized body of both theoretical and practical knowledge (the so-called, 'common core') which is a n.0, pplicable worldwide without regard to national boundaries, levels of economic and technical development or cultural context. The current study is an attempt to validate and su n.0, pport this common core concept through a detailed examination of its important role in the sound development of library and information science both as a learned subject and as a profession. Following an initial overview of generally agreed upon core areas in the education and training of librarians and information specialists, with particular attention to the manifold social changes rapidly being effected by computers and communication technology, the focus shifts to the proliferation of academic homes for information science education and its implications for core areas in information science. Of note here is the relationship between information science as a broadly accepted social science discipline and the evolving core curriculum in library schools. To this regard the fact that the popularization of computers and communication technology is increasingly blurring the once-sharp differences between traditional librarians and information specialists naturally favors common core concept. Major figures in library and information science education such as Shera, Saracevic and Foskette su n.0, pport this concept and have already identified its theoretical infrastructure. Finally, UNESCO and IFLA are also stressing the common core cure curriculum for library and information science both as guidelines for the Third World and as a means to achieve universally accepted academic standards. In conclusion, the search for a comprehensive common core curriculum in library and information science education is still in the elementary stages. The task of identifying the components of this common core is among the most crucial responsibilities facing today's educators and professionals for the successful elaboration of a common core would enable us to attain three highly desirable professional goals: 1) To determine the basic concepts and principles of library and information science. 2) To serve as the base for further professional education and specialized research. 3) To offer enhanced o n.0, pportunities for integrated library and information science education programs by providing a genuine two-way communication channel between the library and information science professions.