• The Korean Journal of Ecology
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• v.8 no.3
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• pp.163-169
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• 1985

The composition rates of litters were studied at Camellia japonica forests in Koje-Do and Haenam, and at Quercus acuta, Quercus acutissima, Cryptomeria japonica, and Chamaecyparis abtusa forests in Haenam. Total amounts of nitrogen, phosphorus, potassium, calcium, and sodium in litter samples were measured and the relation between these amounts and decomposition rate was studied. Annual litter production were rarely different at each forest in Haenam. The amount of accumulated organic matter was about 4 times greater at C. japonica forest in Koje-Do than at the C. japonica forest in Haenam. These amounts were 5, 282.1 $\pm$ 1, 026.03g/m2 in Koje-Do and 1, 420.7 $\pm$ 384.77g/$m^2$ in haenam. The decomposition rate were rarely differnet at each forest in Haenam, but the rates showed great difference at C. japonica foreests in Koje-Do and Haenam. The rates were 0.093 and 0.313 at C. japonica forests in Koje-Do and in Haenam respectively. The sodium contents were 0.472% and 0.229% on L layer and on Css layer of C. japonica forest in Koje-Do, while they were 0.034% and 0.043% on L layer, and on Css layer of C. jpaonica forest in Haenam. It is sugested that much difference in the salt contents in the forest floor was present from the results of sodium content measured at each site, and that the decomposition rate was affected by the much concentration of salt in Koje-Do.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.60-62
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• 2005

This paper describes a feasibility analysis result of STATCOM application for the Jeiu-Haenam HVDC system. The Jeju-Haenam HVDC system is one of the typical HVDC system interconnected with the low short-circuit-ratio AC system, which is vulnerable to the commutation failure due to the AC voltage variation. STATCOM has been considered as an effective reactive-power compensator to increase short-circuit-ratio of the interconnected AC system. In this study, a simulation model of Jeju-Haenam HVDC system with STATCOM was developed using PSCAD/EMTDC. The developed simulation model was utilized to analyze the dynamic performance analysis of Jeju-Haenam HVDC system with STATCOM. The analysis results show that STATCOM can improve the dynamic performance of Jeju-Haenam HVDC system, such as load-change recovery performance and fault recovery performance.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.8
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• pp.401-409
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• 2005

This paper describes a feasibility analysis result of STATCOM application for the Jeju-Haenam HVDC system. The Jeju-Haenam HVDC system is one of the typical HVDC system interconnected with the low short-circuit-ratio AC system, which is vulnerable to the commutation failure due to the AC voltage variation. STATCOM has been considered as an effective reactive-power compensator to increase short-circuit-ratio of the interconnected AC system. In this study, a simulation model of Jeju-Hacnam HVDC system with STATCOM was developed using PSCAD/EMTDC. The developed simulation model was utilized to analyze the dynamic performance analysis of Jeju-Haenam HVDC system with STATCOM. The analysis results show that STATCOM can improve the dynamic performance of Jeju-Haenam HVDC system, such as load-change recovery performance and fault recovery performance.

• Archives of design research
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• v.13 no.1
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• pp.19-28
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• 2000

This research has focused on CI development by regioni government, with emphasis on CI case study of Haenan Chonnam Province. Haenam is located at the most sourthe part of Chonnam Province and famous as a starting point ( Namdo Tour and dinosaur foot traces at Woohangri. CI Ie Haenam county was studied and developed to promote tn pride and love for Haenam and to enhance the uniqu1 image of Haenam to the tourists.

• Journal of Electrical Engineering and Technology
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• v.1 no.1
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• pp.23-27
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• 2006

In this paper a Hybrid Real Time HVDC Simulator fur both operator Training and Researching in the Cheju-Haenam HVDC System is proposed and its performance is studied by means of RTDS (Real Time Digital Simulator), EMTDC (Electro-Magnetic Transients system for DC), PSS/E (Power System Simulator for Engineering), and experienced scenarios. The objective of this paper is to represent the strategy in development for KEPCO's hybrid HVDC simulator for the Cheju-Haenam HVDC system. This simulator consists of two DC stations, DC cables, external digital/analog controllers, monitoring systems and control desk for education, and AC networks. Its suitability for operator's education is tested during startup/shutdown and normal state operations. Dynamic performances of it are also verified.

• Proceedings of the KIEE Conference
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• 2001.05a
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• pp.309-312
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• 2001

The Cheju-Haenam HVDC System is currently being operated in KEPCO's system. But it is quite difficult to control properly due to the newly-introduced system in KEPCO. Therefore, the operators and/or engineers who have little field experiences want to know the system responses for their control actions. To satisfy the needs, the detailed control models which are represented near to real systems are being developed in KEPS project performed by KEPRI. This paper presents the plan for developing the detailed control models and the digital controller based on RTDS of the Cheju-Haenam HVDC system in KEPS project. The EMTDC models of the Cheju-Haenam HVDC system which are the pre-stage models for developing RTDS-based models and digital controllers are also introduced.

• Journal of Ecology and Environment
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• v.36 no.1
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• pp.31-38
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• 2013

Annual ring formation is considered a source of information to investigate the effects of environmental changes caused by temperature, air pollution, and acid rain on tree growth. A comparative investigation of annual ring growth of Cryptomeria japonica in relation to environmental changes was conducted at two sites in southern Korea (Haenam and Jangseong). Three wood disks from each site were collected from stems at breast height and annual ring growth was analyzed. Annual ring area at two sites increased over time (p > 0.05). Tree ring growth rate in Jangseong was higher than that in Haenam. Annual ring area increment in Jangseong was more strongly correlated with environmental variables than that in Haenam; annual ring growth increased with increasing temperature (p < 0.01) and a positive effect of $NO_2$ concentration on annual ring area (p < 0.05) could be attributed to nitrogen deposition in Jangseong. The correlation of annual ring growth increased with decreasing $SO_2$ and $CO_2$ concentrations (p < 0.01) in Jangseong. Variation in annual growth rings in Jangseong could be associated with temperature changes and N deposition. In Haenam, annual ring growth was correlated with $SO_2$ concentration (p < 0.01), and there was a negative relationship between precipitation pH and annual ring area (p < 0.01) which may reflect changes in nutrient cycles due to the acid rain. Therefore, the combined effects of increased $CO_2$, N deposition, and temperature on tree ring growth in Jangseong may be linked to soil acidification in this forest ecosystem. The interactions between air pollution ($SO_2$) and precipitation pH in Haenam may affect tree growth and may change nutrient cycles in this site. These results suggested that annual tree ring growth in Jangseong was more correlated with environmental variables than that in Haenam. However, the further growth of C. japonica forest at two sites is at risk from the long-term effects of acid deposition from fossil fuel combustion.

• Economic and Environmental Geology
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• v.29 no.2
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• pp.151-158
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• 1996

Rb-Sr isochron ages, Sr and Nd isotopic compositions were determined for late Cretaceous granophyre on the Haenam-Wando areas, the southwestern part of the Yeongdong-Kwangju depression in Korea. The granophyre in the Haenam-Wando areas are distributed in the shape of a resurgent cauldron. Five samples of Haenam granophyre give a defined Rb-Sr whole rock isochron age of $75.7{\pm}7.2Ma$ and Sr initial ratio of $0.70826{\pm}0.00020(2{\sigma})$. Plagioclase, orthoclase and whole rock of Haenam granophyre give a defined Rb-Sr whole rock-mineral isochron age of $67.0{\pm}5.8Ma$ and Sr initial ratio of $0.708880{\pm}0.00028(2{\sigma})$. Five samples of Wando granophyre give a defined Rb-Sr whole rock isochron age of $70.6{\pm}3.3Ma$ and Sr initial ratio of $0.70850{\pm}0.00088(2{\sigma})$. Eight samples of Haenam granophyre give a defined Nd isotope ratios of 0.512180~0.512259 and ${\varepsilon}Nd$ (T) values of -6.53~-8.15, ${\varepsilon}Sr$ (T) values of +51.49~+66.48 and model age of 1.28~1.60 Ga. Four samples of Wando granophyre give a defined Nd isotope ratios of 0.512228~0.512289 and ${\varepsilon}Nd$ (T) values of -6.74~-8.00, ${\varepsilon}Sr$ (T) values of +54.88~+78.98 and model age of 1.14~1.42 Ga.

• Economic and Environmental Geology
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• v.24 no.2
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• pp.83-96
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• 1991

Haenam pyrophyllite deposit occurred in the rhyolitic tuff of late Cretaceous age is located in the northern part of Haenam-gun, Jeonranam-do. The ore of the Haenam deposit is predominantly composed of pyrophyllite and illite accompanying such clay minerals as kaolinite, chlorite, and smectite. Pyrophyllite ore at the center of altered mass is often associated with kaolin minerals and high temperature minerals such as corundum, andalusite, and diaspore. On the basis of mineral assemblage the Haenam deposit can be devided into three alteration zones from the center to the margin of the deposit; the pyrophyllite zone, kaolinite zone, and illite zone. All alteration zones are associated with appreciable amounts of chalcedonic quartz. Those mineral assemblages indicate that hydrothermal solution which produced the Haenam deposit is strongly acidic solution with high silica and hydrogen activity and low $SO_4{^{2-}}$ activity. Discriminant analysis shows that $Na_2O$, $K_2O$, and $Al_2O$, of major elements are discriminant elements which classify alteration zones, while in case of trace elements Cr, Ni, and Sr turned out to be discriminant elements in this deposit. According to the mineral assemblage and illite geothermometry, pyrophyllite ore is considered to have been formed at about $240-290^{\circ}C$. K-Ar isotopic age for illite from this deposit indicates that it was formed at much the same age of later stage volcanics in the area, suggesting that the hydrothermal alteration of these deposits is associated with later volcanism of the area.

• Economic and Environmental Geology
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• v.25 no.1
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• pp.41-50
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• 1992

Mineral assemblages, mineral chemistries and stable isotope compositions of altered rocks of the Ogmae, Seongsan, Haenam and Gusi mines near the Haenam volcanic field in the southwestern part of the Korea peninsula were studied. Characteristic hydrothermal alteration zones in these deposits occurring in the Cretaceous volcanics and volcanogenic sediments, acidic tuff, and rhyolite, were outlined. Genetic environment with particular reference to the spatial and temporal relationships for these deposits were considered. The alteration zones defined by a mineral assemblage in the Ogmae and Seongsan deposits can be classified as alunite, pyrophyllite, kaolinite or dickite, quartz, illite or illite/smectite. Alunite was not developed in the Gusi and Haenam deposits. Boundaries between the adjacent zones are always gradational except for vein-type alunite. Alteration zones are superimposed upon each other in some localities. These deposits formed $71.8{\pm}2.8{\sim}76.6{\pm}2.9$ Ma ago, which is the almost same age of later volcanic rocks $79.4{\pm}1.7{\sim}82.8{\pm}1.2$ Ma, the Haenam Group, corresponding to Campanian. It indicates that hydrothermal alteration of these deposits appeared to be related to felsic volcanism in the area. Consideration of the stability between kaolinite, alunite, pyrite and pyrophyllite, and the geothermometry based on the mineral chemistry of illite and chlorite suggests that the maximum formation temperature for alunite and pyrophyllite can be estimated at about $250^{\circ}C$ and $240{\sim}290^{\circ}C$, respectively. It also suggests that these deposits were formed by acidic sulfate solution with high aqueous silica and potassium activity in a shallow depth environment. Compositional variation of alunite also suggests that the physico-chemical conditions fluctulated considerably during alteration processes, indicating shallow depth environment. The Haenam deposit was formed at a relatively greater depth than the others. The sulfur isotope composition of alunite and pyrite indicates that sulfur probably had a magmatic source, and the oxygen isotope composition for kaolinite indicates that the magmatic hydrothermal solution was diluted by circulating meteoric water.