• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.234-236
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• 2011

Saigon Port within the port system of the Vietnam Maritime sector is one of the port having highest throughput and productivity in the country. The marine traffic of Saigon water ways is the heaviest in Vietnam and the number of marine accidents in this area are much higher than the others area in Vietnam. In order to reduce the risk of the accident in Saigon fairway, this paper concentrates on marine accident frequency in this area. The marine traffic and the marine accident were analyzed to find out the probability of vessel collision and the marine traffic risk. It follows that the main shipping route through Saigon fairway has the high risk of ship-ship collision.

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.1-8
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• 2006

Recently, many ships such as VLCCs, dangerous cargo ships, high speed ferry boats are visiting Yeosu, Gwangyang harbor. The traffic volume of the year 2003 has increased as many as 2.5 times of 1988. However there is no suitable ships' routeing system which takes account of today's traffic situations in this area This study aims at the settling of hazardous factors to mitigate the danger to vessels in Yeosu${\cdot}$Gwangyang bay and to secure the safety of maritime environment.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.197-204
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• 2005

Recently, many ships such as VLCCs, dangerous cargo ships, high speed ferry boats are visiting Yeosu ${\cdot}$ Gwangyang harbor. The traffic volume of the year 2003 has increased as many as 2.5 times of 1988. However there is no suitable ship's routeing system which takes account of today's traffic situations in this area. This study aims at the setting of hazardous factors to mitigate the danger to vessels in Yeosu ${\cdot}$ Gwangyang bay and to secure the safety of maritime environment.

• Journal of Environmental Science International
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• v.6 no.5
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• pp.451-459
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• 1997

This paper alms to describe the indoor-outdoor air quality in school environment through the analyses of heavy metal concentration by inductively Coupled Plasma(ICPI, which were observed at some school environment, such as traffic area, industrial area seme-industrial area, and residence area. The results are as follows : (1) Regardless Indoor and outdoor, the area with the highest concentration of heavy metal is industrial area followed by traffic area, residence area and semi-industrial area in descending order of magnitude. And the heavy metal concentration of indoor is higher than that of outdoor. (2) The main heavy metal components with more high level concentration of Indoor than those of outdoor are Zn, Al, Ca and these heavy metal concentrations are higher in class than In corridor and outdoor.

• International Journal of Highway Engineering
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• v.14 no.5
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• pp.11-19
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• 2012

PURPOSES: The new methodology is proposed for estimation of long-term performance and pavement life based on the national highway database in Daejeon area. Furthermore, this study tried to verify the applicability of performance estimation using NHPCI (National Highway Pavement Condition Index) on tendency of pavement deterioration as time goes by under Korean road environments. METHODS: Reliability theories are applied to estimate the mean life and to determine the appropriate distribution using 3 levels of traffic loads (high, medium, low) based on maintenance and rehabilitation history data for 15 years. RESULTS: As a result, Lognormal distribution is suitable for explanation of pavement lifetime in Daejeon area regardless of traffic loads. In addition, we found that the results of mean life and maintenance timing based on NHPCI for the pavement sections of 3 levels of traffic loads are available. CONCLUSIONS: Based on this study, it was found that mean life of high, medium and low levels of traffic loads are about 8.1 years, 12.2 years and 12.7 years, respectively. Higher level of traffic loads shorten the pavement mean life.

• Journal of the Korean Operations Research and Management Science Society
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• v.26 no.4
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• pp.125-132
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• 2001

Traffic unbalance between uplink and downlink is one of the most notable characteristics in the next generation cellular mobile systems which provide multimedia services such as voice and video telephony, high-speed internet access, and mobile computing, etc. The CDMA/TDD system with unbalanced slot allocation between two links is a good solution for the traffic unbalance in this paper, we formulate the time slot and channel allocation problem for the CDMA/TDD systems in general multicell environments, which is to maximize the system capacity under the given traffic unbalance, and solve that problem by simulated annealing technique. Computational experiments show that the proposed scheme yields a good performance.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.294-297
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• 2006

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.138-141
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• 2010

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

• Journal of Korea Ship Safrty Technology Authority
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• s.28
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• pp.36-45
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• 2010

While the vessel become bigger and high speed, navigational passages become narrow due to an enlargement of all sorts of new ports, sea-crossing bridges and anchorages, leading to the high probability of marine accidents. Furthermore, a constant increase in the maritime transportation and the traffic volume on the sea led to a variety of sea traffic environments and it is a trend for the demand for the sea transportation environment to increase steadily. At this point of time, the Ministry of Land, Transport, and Maritime Affairs introduced the Korea Maritime Safety Laws evaluating the degree that The Safety Audit System for maritime transport, which evaluates the degree that all kinds of port facilities installed temporarily or installed into navigational passages, and the installations and repair constructions of S.O.C. facilities affect ships' traffic safety, was introduced through Korea Maritime Safety Laws and went into effect from November 28th, 2009. This study was performed to introduce an outline including the concept and purpose of the Maritime Safety Audit(MSA) system for maritime transport and the technological guidelines for scientific and standardized enforcement, thereby analyzing the system.

• Journal of Environmental Science International
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• v.32 no.9
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• pp.627-634
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• 2023

Tire wear particles(TWPs), regarded as a microplastic, is generated in significant quantities each year and exist in various spaces and have a negative impact on the surrounding environment. Particularly, roadside environments fall within the direct influence of TWPs, necessitating proactive investigation for contamination management and response. Therefore, this study aimed to investigate the soil acidity and electrical conductivity(EC) and TWPs in the roadside soil of six sites based on traffic volume. The analysis revealed that the soil in all sites exhibited subacidity, and there were no significant differences in EC. Microscopic and FT-IR analysis revealed the presence of microscopic particles in soil samples that exhibited common visual characteristics of TWPs. In the road with the highest traffic volume, 48,300 TWPs were detected per unit area. Furthermore, a proportional relationship between traffic volume and TWPs particles was established. However, influences other than traffic volume on TWPs particle count within the soil were observed. Therefore, for the management of TWPs contaminated roadside soil, a proactive response is necessary in areas with high traffic volumes. However, in order to effectively address the factors contributing to the generation and dispersion of TWPs, further research is required with a multidimensional approach.