• Journal of Navigation and Port Research
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• v.28 no.6
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• pp.557-564
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• 2004

The WAM wave model has been widely used for wave hindcasting in the ocean by many domestic and foreign researchers due to its relative simplicity and high accuracy. As this model was originally developed for the condition of deepwater and comparatively coarse grid size covering wide area, it might produce in a fault result caused by the improper distribution of directional spreading. We extensively investigated involved problems based on WAM Cycle 4 model and suggested the improved WAM model so that it is applicable to both shallow water sea and fine mesh wave simulation The modified W AM model is verified here by comparing the computed result with and the observed data at Ieodo Ocean Research Station for September of 2003.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.3
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• pp.119-129
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• 2004

The surges caused by the typhoon “Maemi” which struck the southern coast of Korea are analysed in Kwangyang Bay on September 12, 2003. The deviations of the high water level were 93∼108 cm and the maximum deviations of the water level (maximum surges) were 176∼196 cm in Kwangyang Bay during the typhoon “Maemi”. The major parameters of the maximum deviations of the water level are as follows: Analysis shows that the pressure drop increased the sea level by 59 cm, the flood of the Sumjin River by 4-5 cm and the external surge propagation and wind setup by 113∼132 cm. During the typhoon “Maemi”, the highest high water recorded in Kwangyang Port (PT3) is 460 cm, which is higher by 5 cm than the highest high water (455 cm) with return period of 100 years estimated in planning the Kwangyang steelworks (POSCO) grounds and higher by 15 cm than the observed highest high water (445 cm) recorded during the typhoon “Thelma” on 1987. Thus, the highest high water caused by the typhoon “Maemi” is higher than the extreme highest high water for the last 20 years in Kwangyang Bay.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.415-422
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• 2018

Lycorma delicatula, known as spotted lanternfly, is a planthopper native to Southeast Asia, including Vietnam, India and South China. This species damages local fruit trees and has spread rapidly in South Korea in recent years. The purpose of this study is to present the methods and estimation results pertaining to the risk of invasive species like Lycorma delicatula. We used a partial budget (PB) method to assess direct income reduction of farm households and a partial equilibrium (PE) model to examine social welfare change from the outbreak of Lycorma delicatula. We also estimated the future economic impacts of Lycorma delicatula under various climate scenarios considering habitat suitability. As climate change progresses, domestic ecosystems are expected to become increasingly vulnerable to pest outbreaks leading to further economic damage. We believe that this study can be a base to evaluate efficiency of the national pest control and quarantine system.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.9
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• pp.825-829
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• 2012

The global warming caused the changes of our environment like an increasing tropical night phenomenon in the middle latitude areas. Especially, in Korea, the habitats of tropical Korean blockish cicada have changed from Jeju island located in Southern part of Korea to the whole of Korea because of the increasingly warming weather. The cicadas crying sound have been social problem because the tropical Korean blockish cicadas cry at middle of the night owing to the various outdoor lights. The cicada is positive phototaxis insect. So, the cicada is not cry at night. But if the outdoor light is very bright, then the cicada confuse the night as a day and start to cry. As a result, the cicadas crying noise has caused the resident living in downtown to an unpleasure and sleeplessness. In this research, we have measured three kinds of cicada singing noise at 16 points of urban area(Incheon, Gwangju, Busan, Gyeonggido Anyang). And then we analyzed the sound quality of the three kinds of cicada singing noise using by CADA-X signal process program. And we analyzed the acoustical characteristics by STFT(short time Fourier transform) which is a time-frequency analysis method. The characteristics of the cicada singing noise in terms of the sound quality and the time-frequency variation will be usefull to discover the relations between the human annoyance about the cicada singing noise and the acoustical characteristics.

• Korean journal of applied entomology
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• v.17 no.4 s.37
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• pp.187-191
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• 1978

This experiment was conducted to determine the optimum temperature and day-length condition for laboratory multiplication of Green Rice Leafhopper, Nephotettix cincticeps Uhler, and to obtain basic information for deriving temperature dependent growth rate function. The insects which were reared in $33-35^{\circ}C$ have relatively short nymphal periods and high adult emergence rate compared with the insects which were reared in $27-29^{\circ}C$ The adults which emerged in $35^{\circ}C$ laid significantly smaller number of eggs than the adult reared in $27-29^{\circ}C$ during their nymphal stage. Day length in $29^{\circ}C$ did not have any influence to the nymphal growth, adult emergence rate and egg laying of the insect. The growth rate of the insect did not have linear relation with rearing temperature.

• Korean Journal Plant Pathology
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• v.1 no.3
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• pp.184-189
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• 1985

Transmission of mulberry dwarf mycoplasma (MDM) from diseased mulberry to 5 herbaceous plants (periwinkle, white clover, Ladino clover, red clover, and Chinese milk vetch) through insect vector, Hishimonus sellatus, was confirmed by symptom expression and microscopic evidences. The earliest symptom appearance was noticed on periwinkle in which incubation period was 25-30 days, while it ranged 35-40 days in the other plant species. The common symptoms of MDM infected plants were characterized by poor plant growth with accompanying discolorations of leaves (chlorosis with vein clearing in periwinkle, reddish in red clover, brownish in white and Ladino clovers, and yellowish in Chinese milk vetch). Mycoplasmal infections were diagnosed light microscopically by Dienes' and toluidine blue staining of hand-cut and Epon-embedded sections, respectively. In Dienes' stain, all the plants infected with MDM showed specific staining reaction in phloems. In toluidine blue stain, mycoplasmal existence was noted by granular appearance in sieve tubes which were confirmed to be mycoplasma-like organisms under an electron microscope.

• The Korean Journal of Mycology
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• v.31 no.1
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• pp.8-13
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• 2003

The fruiting body of Paecilomyces sinclairii was collected in Baekyangsa, Jeollanam-Do, Korea. Cultural conditions for the mycelial growth and fruiting body formation were investigated. Its optimum mycelial growth was obtained at 25℃ and pH 8 on potato dextrose agar and Hamada media among the various media tested. The carbon and nitrogen sources for the optimum mycelial growth were dextrin and glutamine, respectively. The optimum C/N ratio was about 20:1 in case that 1% glucose was supplemented to the basal medium as a carbon source. The favorable mycelial growth was obtained from corn meal extract medium mixed with 30% (w/v) milk solution. The maximum fruiting body was formed in unpolished rice medium supplemented with 20% (w/w) silkworm pupae at $25^{\circ}C$ under 500lux.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.492-495
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• 1992

Life cycle of the mirid predator, Cyrtorhinus lividipennis, was observed on the constant temper¬ature. Egg periods were 14.43, 9.33 and 6.94 days at $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively. Nymph periods were 24.3, 14.42, and 11.90 days at $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively and fe¬male longevity was 11.20, 11.93 and 11.87 days at above temperatures. Relationships between constant temperature and the developmental velocity of egg, nymph and egg-nymph were lin¬ear over temperatures tested. The calculated threshold temperatures of development were $10.7^{\circ}C$ in egg, $9.8^{\circ}C$ in nymph and $10.2^{\circ}C$ in egg-nymph. Total effective day-degrees were 133.9 in egg, 235.8 in nymph and 368.0 in egg-nymph. Number of eggs laid was 26.0 and 22.4 at $24^{\circ}C$ and $30^{\circ}C$, respectively.

• Journal of Ocean Engineering and Technology
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• v.22 no.3
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• pp.8-17
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• 2008

Wrenching climatic changes due to ecocide and global wanning are producing a natural disaster. Coastal zones have been damaged by typhoons and accompanying storm surges. Severe waves, and destruction of the environment are adding to the severity of coastal disasters. There has been an increased interest in these coastal zone problems, and associated social confusion, after the loss of life and terrible property damage caused by typhoon Maemi. Especially if storm surges coincide with high ticks, the loss of life and property damage due to high waters are even worse. Therefore, it is desirable to accurately forecast not only the timing of storm surges but also the amount water level increase. Such forecasts are very important from the view point of coastal defense. In this study, using a numerical model, storm surge was simulated to examine its fluctuation characteristics for the coastal area behind Masan Bay, Korea. In the numerical model, a moving boundary condition was incorporated to explain wave run-up. Numerically predicted inundation regimes and depths were compared with measurements from a field survey. Comparisons of the numerical results and measured data show a very good correlation. The numerical model adapted in this study is expected to be a useful tool for analysis of storm surges, and for predicting inundation regimes due to coastal flooding by severe water waves.

• Korean Journal of Environment and Ecology
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• v.17 no.3
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• pp.210-223
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• 2003

This study was carried out to investigate the flora of Mt. Baekwoon. The flora of Mt. Baekwoon was surveyed from October, 2000 to August, 2001. In the results of survey, the vascular plant species in Mt. Baekwoon were summarized as 468 taxa; 90 families, 272 genera, 411 species, 1 subspecies 49 varieties and 7 forms. The rare plants designated by Korea Forestry Service were nine species; Lilium distichum, Gastrodia elata, Viola diamantica, Hylomecon hylomeconoides, Aristolochia contorta, Asarum maculatum, Rodgersia podophyllu, Viola albida, Scopolia japonica and Scrophularia koraiensis. And the endemic plants were nineteen species; Asarum maculatum, Melandryum seoulense, Clematis trichotoma, Aconitum pseudo-laeve var. erectum, Hylomecon hylomeconoides, Chrysosplenium barbatum, Spiraea prunifolia for. simpliciflora, Robus hongnoensis, Vicia venosa var. cuspidata, Tilia taquetii, Viola seoulensis, Viola diamantica, Ajuga spectubilis, Scrophularia koraiensis, Weigela subsessilis, Adenophora remotiflora, Cirsium setidens, Saussurea macrolepis and Saussurea seoulensis.