• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.25-28
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• 2003

This study was conducted to development of rapid propagation method by leaf cuttings in Hibiscus hamabo native to southern seaside of Korea, and special object of this study was to determine the effects of IAA, IBA, and NAA on rooting in leaf cuttings of H. hamabo. Rooting was promoted by dipping treated with IAA and IBA. And rooting percentage was greatest at 1,000 and 2,000$mg{\cdot}L^{-1}$ IBA. At higher concentrations of IAA and IBA, more adventitious roots were developed. Also, IAA at high concentrations (above 2,000$mg{\cdot}L^{-1}$) and IBA ranged from 500~2,000$mg{\cdot}L^{-1}$ promoted on root number and rootingratio. However, root formation in Hibiscus leaf cuttings inhibited by NAA application.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.285-294
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• 1995

A comparative study on the chemical compositions of precipitations from February 1993 to April 1993 in Sungnam city of Kyunggi province, Inchon city, Kangneung city of Kangwon province, and Chongwon-gun of Chungbuk province has been performed. The metal cation and anion concentrations were measured by atomic absorption spectrometer and ion liquid chromatography, respectively. pH/Ion meter and direct nesslerization method were used for the concentration measurements of $H^+$ and $NH^{4+}$ ions, respectively. The quantitative orders of the cation and anion average concentrations, correlation coefficients between the ion concentrations, and pH values are used for chemical analysis on the environmental pollution and pollutant sources in the urban, surburban, seaside, and rural areas of the Korean Peninsula.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.3
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• pp.531-535
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• 2010

345kV Incheon Thermal Power Plant Transmission Line Collapse Analysis and Countermeasures. The Typhoon Galmaegi which had been formed in July 15, 2008 diminished into a tropical cyclone and cooled the air above the West Sea. The cooled air colliding with the warm inland air caused a strong whirlwind at some places in the west seaside; the whirlwind battered the 345kV Incheon Thermal Power Plant Transmission Line to be collapsed. The resistance of transmission towers against wind pressure, one of the key elements in transmission line engineering, is designed to endure the pressure corresponding to the maximum instantaneous wind speed. Before the above accident happened, no transmission line has ever been collapsed by a whirlwind. So this paper is aimed to analyze causes that collapsed 345kV Incheon Thermal Power Plant transmission line and to introduce countermeasures.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.323_324
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• 2009

345kV Incheon Thermal Power Plant Transmission Line Collapse Analysis and Countermeasures. The Typhoon Galmaegi which had been formed in July 15, 2008 diminished into a tropical cyclone and cooled the air above the West Sea. The cooled air colliding with the warm inland air caused a strong whirlwind at some places in the west seaside; the whirlwind battered the 345kV Incheon Thermal Power Plant Transmission Line to be collapsed. The resistance against wind pressure, one of the key elements in transmission line engineering, is designed to endure the pressure corresponding to the maximum instantaneous wind speed. Before the above accident happened, no transmission line has ever been collapsed by a whirlwind. So this paper is aimed to analyze causes that collapsed 345kV Incheon Thermal Power Plant transmission line and to introduce countermeasures.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.4
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• pp.361-368
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• 1998

Acid rainwater samples were collected during 4 years from 1992 in Pusan area nearby seaside. Ionic composition of early and succeeding rainwater were investigated to identify emission sources. pH and Electronic Conductivity of samples were measured immediately after sampling. Major ion concentrations of rain samples were Na+, Ca2+, Mg2+, K+, NH4+, SO42-, NO3-, Cl- which were analyzed by ion Chromatography. 55% of early rainwater and 90% of succeeding rainwater were identified below pH 5.6. Because, Na+, K+, Ca2+ were washed mostly in early rainwater, as a result, pH values were increased by increasing rainfall amounts. It was studied that pH value was varied from ambient ion component, rainfall, and rain intensity. From the principal component analysis result, the dominant components of acid rainwater were Na+, K2+, Mg2+, Ca2+, the elements were contributed soil and marine source, the second components nuts -SO42-, SO4a-, NO3-, nuts -Ca2+ originated from man - made source.

• Management Science and Financial Engineering
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• v.6 no.2
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• pp.47-67
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• 2000

It is discussed how to assign delivery tasks to automated guided vehicles (AGVs) for multiple container cranes in automated container terminals. The primary goal of dispatching AGVs is to complete all the lading and discharging operations as early as possible, and the secondary goal is to minimize the total travel distance of AGVs. It is assumed that AGVs are not dedicated to a specific container crane but shared among multiple cranes. A mathematical formulation is developed and a heuristic algorithm is suggested to obtain a near optimal solution with a reasonable amount of computational time. The single-cycle and the dual-cycle operations in both the seaside and the landside operations are analyzed. The effects of pooling AGVs for multiple container cranes on the performance of an entire AGV system are also analyze through a numerical experiment.

• Structural Monitoring and Maintenance
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• v.2 no.1
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• pp.49-64
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• 2015

This paper presents a method for assessing the risk of wave run-up and overtopping of existing coastal defences and for analysing the probability of failure of the structures under future hydraulic conditions. The recent UK climate projections are employed in the investigations of the influence of changing environments on the long-term performance of sea defences. In order to reduce the risk of wave run-up and overtopping caused by rising sea level and to maintain the present-day allowances for wave run-up height and overtopping discharge, the future necessary increase in crest level of existing structures is investigated. Various critical failure mechanisms are considered for reliability analysis, i.e., erosion of crest by wave overtopping, failure of seaside revetment, and internal erosions within earth sea dykes. The time-dependent reliability of sea dykes is analysed to give probability of failure with time. The results for an example earth dyke section show that the necessary increase in crest level is approximately double of sea level rise to maintain the current allowances. The probability of failure for various failure modes of the earth dyke has a significant increase with time under future hydraulic conditions.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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• pp.117-122
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• 2015

There has been a string of negligent accidents at the seaside, and there is presently a shortage of professional equipment to deal with such accidents. The purpose of this paper is to assess the development of a rescue lift. The critical load of a support pipe, and the stability of the rescue lift, were investigated using structural analysis. Critical-load analysis was used to study the effects of variations in the pipe length and the ratio of the moment of inertia. The total weight of the developed rescue lift is approximately 20.7 kg, and the lift passed the load tests.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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• pp.111-116
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• 2015

There has been a string of negligent accidents at the seaside. In addition, there is a shortage of professional equipment to deal with these negligent accidents at present. The purpose of this paper is to assess the development of a rescue lift using a structural analysis. The critical load of a support pipe on the rescue lift is investigated in this paper. The stability of the rescue lift is also determined in a structural analysis. In the critical load analysis, the effects of variations in the pipe length and the ratio of the moment of inertia are investigated. The total weight of the developed rescue lift is approximately 20.7kg, and the lift passed the load tests.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1709-1711
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• 2001

The remaining life of ACSR(Aluminum Conductor Steel Reinforced) wires exposed to the atmosphere for a long period relies on the extent of deterioration caused by environmental factors such as atmospheric corrosion, galvanic corrosion, crevice corrosion and fatigue corrosion. We investigated the tensile characteristics of ACSR wires in a coastal area through several mechanical tests, and analyzed the constituents of them using SEM(scanning electron microscope). Test samples are parts of ACSR 97[$mm^2$] overhead transmission lines in that area. The result shows that ACSR wires exposed to salt may lead to rapid mechanical deterioration.