• 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.

• Geophysics and Geophysical Exploration
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• v.14 no.2
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• pp.127-132
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• 2011

We acquired and interpreted more than 650 km of high-resolution seismic reflection profiles in the Hupo Basin, offshore east coast of Korea at $37^{\circ}N$ in the East Sea (Japan Sea) to image shallow and basement deformation. The seismic profiles reveal that the main depocenter of the Hupo Basin in the study area is bounded by the large offset Hupo Fault on the east and an antithetic fault on the west; however, the antithetic fault is much smaller both in horizontal extension and in vertical displacement than the Hupo Fault. Sediment infill in the Hupo Basin consists of syn-rift (late Oligocene. early Miocene) and post-rift (middle Miocene.Holocene) units. The Hupo Fault and other faults newly defined in the Hupo Basin strike dominantly north and show a sense of normal displacement. Considering that the East Sea has been subjected to compression since the middle Miocene, we interpret that these normal faults were created during continental rifting in late Oligocene to early Miocene times. We suggest that the current ENE direction of maximum principal compressive stress observed in and around the Korean peninsula associated with the motion of the Amurian Plate induces the faults in the Hupo Basin to have reverse and right-lateral, strike-slip motion, when reactivated. A recent earthquake positioned on the Hupo Fault indicates that in the study area and possibly further in the eastern Korean margin, earthquakes would occur on the faults created during continental rifting in the Tertiary.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.423-432
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• 2004

In coastal area of Inchon, dredging and the disposal of dredged material for sea-wall construction and reclamation have increased in recent years. These activities may impact the benthic environment and result in changes in benthic communities, but little information is available on the extent and direction of these changes. We investigated whether there have been changes in the dominant macrobenthic species and benthic community over the last decade, and explored the relationship between environmental variables and spatial patterns of macrobenthic community structure. We sampled macrobenthos and recorded environmental variables in the coastal habitats of Inchon in March and June 2004. In total, 212 macrobenthic species were recorded during this study, predominately crustaceans $(34{\%})$, mollusks $(32{\%})$ and polychaetes $(21{\%})$. The mean density of macrobenthos was $1,393\;ind./m^{2}$.The most abundant species was Amphioplus japonicus $(20.5{\%})$, followed by Heteromastus filiformis $(14.4{\%})$, Theora fragilis $(8.2{\%})$ and Ampharete sp. $(4.0{\%})$. Over the past decade the dominant macrobenthic species in this area shifted. Multivariate analysis (multidimensional scaling) revealed significant differences in community structure among three regions: the middle part of the sampling area (B), site 8 (C) and other sites (A). Mean density varied significantly among the three regions, but no differences in the number of species and diversity (H') were observed. The distribution of the macrobenthic community was affected by environmental variables such as percentage sand content and sediment kurtosis. Species that were important in different areas included A. japonicus in region A, Raeta puchella in region B and T. fragilis in region C. The important species in regions B and C were filter-feeding bivalves, and the abundance of these species may be related to the increase in percentage sand content. We suggest that the sediment composition (percentage sand content) may be an important factor in determining the dominant species and structure of the macrobenthic communities in coastal Inchon. Long-term monitoring programs are necessary to understand ongoing changes in the benthic communities of this area.

• Journal of architectural history
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• v.16 no.1
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• pp.9-28
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• 2007

We investigated the changes in the species of the woods used for Korean ancient and historic architectures, which include prehistoric excavated relics and existing wooden buildings in South Korea. The species data were collected from various sources such as excavation and repair reports, journal papers, and a few unpublished documents. We divided the building Periods as Paleolithic, Neolitic, Bronze Ages, Iron Age/Three Kingdoms, Koryo, Joseon (early, middle, late) and modem periods. In prehistoric periods, hardwoods were major species. Oak (Quercus spp.) woods dominated (94 percent in average); the others (5%) were Juglans mandshurica, Platycarya strobilacea, Castanea crenata, and few softwoods(1%). During Iron Age and Three Kingdom periods, oaks remained as a major species (57%) and others Platycarya strobilacea(21%), Castanea crenata(13%), and Pinus spp. (6%). The oak woods decreased in Koryo period and they occupied only 1.1%. Instead of oaks, pine (Pinus spp., 71%) and Zelkova serrata (22%) dominated in Koryo. In early and middle Joseon periods, pine woods (73%) remain as a major species and the others were oaks (14%) and Zelkova serrata (9%). As late Joseon came, the pine woods occupied more than 88%. In the late 19th and early 20th centuries, a few boreal species such as larch (Larix spp.) and spruce (Picea spp.), which grow in cold area, were found. We believe they were transported from northern Korea. The existing buildings in Korea are mainly from Joseon period and a few from late Koryo periods. During these periods, pine woods were used for most buildings. For such reason, pine woods were known as 'representative materials for historic buildings'. but earlier times, broad-leaved trees, i.e., oak and Zelkova woods were major materials. The changes in building materials resulted from both climate and human impacts. The dry climate and disturbed forests induce more pines in the mountains. We also compared the wood qualities of the species and found that Zelkova woods were superior ones and deserved more planting for future demands in the repair for historic buildings.

• Korean Journal of Community Nutrition
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• v.9 no.4
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• pp.491-500
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• 2004

To assess the quality of nutrient intake by area of Korean adults, a dietary survey with the 3-day record method was obtained from 324 subjects aged 40 years and older but younger than 70 (52.4 $\pm$ 8.7) living in a rural area (Ansung) and suburban area of a middle-sized city (Ansan). The quality of nutrient intake was assessed by analyzing Nutrient Adequacy Ratio (NAR), Mean Adequacy Ratio (MAR) and Index of Nutritional Quality (INQ). The average daily mean energy intakes were 1,832 ㎉ for Ansung and 1,842 ㎉ for Ansan, respectively. Daily intakes of fat for Ansung and Ansan subjects were 40.9 and 40.3 g, and those for protein were 75.1 and 73.1 g, respectively. The overall calorie: protein: fat ratio (CPF) of energy intake was 63 : 17 : 20. Daily mean intakes of protein, fat, calcium, phosphorus, iron, potassium, carotene, sodium, thiamin, and niacin were significantly higher in Ansung residents than in Ansan subjects (p < .05). The average intakes of energy, calcium, vitamin A were lower than Recommend Dietary Allowance (RDA) in both areas. Note, over 30% of the study subjects had less than 75% of RDA of calcium, vitamin A and riboflavin. The MAR was higher in Ansung than Ansan residents (0.86 and 0.85, respectively; p < .05). INQs were over 1 for most nutrients except calcium (0.87), and that of calcium and phosphorus was each significantly higher in Ansung than Ansan subjects. Based on these results, nutrient intake quality of subjects aged 40 to 69 years living in the surveyed rural area is comparable to that of semi-industrialized suburban area in Korea. Dietary deficiency in all of calcium, vitamin A, and riboflavin, however, was a common problem for both rural and suburban residents.

• The Journal of the Petrological Society of Korea
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• v.28 no.1
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• pp.25-38
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• 2019

The Muju-Seolcheon area, which is known to be located in the boundary of Ogcheon Belt and Ryeongnam Massif (OB-RM), consists of age unknown or Precambrian metamorphic rocks (MRs) [banded biotite gneiss, metasedimentary rocks (black phyllite, mica schist, crystalline limestone, quartzite), granitic gneiss, hornblendite], Mesozoic sedimentary and igneous rocks. In this paper are researched the structural characteristics of each deformation phase from the geometric and kinematic features and the developing sequence of multi-deformed rock structures of the MRs, and is considered the boundary location of OB-RM with the previous geochemical, radiometric, structure geological data. The geological structure of this area is at least formed through four phases (Dn-1, Dn, Dn+1, Dn+2) of deformation. The Dn-1 is the deformation which took place before the formation of Sn regional foliation and formed Sn-1 foliation folded by Fn fold. The Dn is that which formed the Sn regional foliation. The predominant Sn foliation shows a NE direction which matches the zonal distribution of MRs. A-type or sheath folds, in which the Fn fold axis is parallel to the direction of stretching lineation, are often observed in the crystalline limestone. The Dn+1 deformation, which folded the Sn foliation, took place under compression of NNW~NS direction and formed Fn+1 fold of ENE~EW trend. The Sn foliation is mainly rearranged by Fn+1 folding, and the ${\pi}$-axis of Sn foliation, which is dispersed, shows the nearly same direction as the predominant Fn+1 fold axis. The Dn+2 deformation, which folded the Sn and Sn+1 foliations, took place under compression of E-W direction, and formed open folds of N-S trend. And the four phases of deformation are recognized in all domains of the OB-RM, and the structural characteristics and differences to divide these tectonic provinces can not be observed in this area. According to the previous geochemical and radiometric data, the formation or metamorphic ages of the MRs in and around this area were Middle~Late Paleproterozoic. It suggests that the crystalline limestone was at least deposited before Middle Paleproterozoic. This deposition age is different in the geologic age of Ogcheon Supergroup which was recently reported as Neoproterozoic~Late Paleozoic. Therefore, the division of OB-RM tectonic provinces in this area, which regards the metasedimentary rocks containing crystalline limestone as age unknown Ogcheon Group, is in need of reconsideration.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.1
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• pp.21-29
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• 2013

The studies were conducted to investigate real condition of mycotoxin contamination in the fields before harvest and by the storages of rice straw used as roughage in Korea. It was found mycotoxin contamination before harvest of rice straw that the rice plants were detected deoxynivalenol at the initial growth, ochratoxin A and deoxynivalenol at the middle growth, and deoxynivalenol and zearalenone at the harvest periods in the fields. Also, the rice plants were contaminated by various fungi such as Fusarium sp., Fusarium proliferatum, Penicillium sp., Gibberella sp., Gibberella zeae, Mucor circinelloides and Aspergillus oryzae. The levels of fungal contamination were $10^{3-4}$ cfu/g at the initial growth, and $10^{4-5}$ cfu/g at the middle growth and harvest periods. All storage types of rice straw were contaminated with zearalenone, deoxynivalenol and ochratoxins A. The samples of rice straw contaminating mycotoxins were account for 3% in bundle rice straw, and 38% in both types of square rice straw and rice round bale silage, respectively. When 105 samples of rice bale silage were analyzed for mycotoxins depending on the regional area, mycotoxin contamination was found in 46% of total samples in Korea. Regional contaminations of mycotoxins were respectively 48, 33, 40, 50 and 57% of samples in Gyeonggi, Gangwon, Chungcheng, Yeongnam and Honam area. Rice round bale silage was contaminated by three kinds of mycotoxins (zearalenone, deoxynivalenol and ochratoxinsA) in the all of area without Chungcheong area where was contaminated zearalenone and deoxynivalenol. Ochratoxins A, deoxynivalenol and zearalenone were respectively determinated with the average levels of 2.6, 413 and $338{\mu}g/kg$ in rice round bale silage for the overall area, even if it was some difference depending on each regional area. Therefore, the above results clearly show that the rice straws were exposed to the contamination by mycotoxin and mycotoxigenic fungi before harvest in the fields, and mycotoxin contamination was not dependent on the regional area or the storage types such as bundle rice straw, square rice straw and rice round bale silage.

• Economic and Environmental Geology
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• v.36 no.3
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• pp.233-242
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• 2003

The southeasternmost coastal area of the Korean peninsula has been regarded as a seismologically stable area as neither Quaternary faults nor earthquake activity has been reported. To clarify whether the active tectonic movement has occurred or not, a digital marine terrace mapping and fracture mapping have been done in the coastal area. Bed rocks are composed of the Cretaceous volcanic and sedimentary rocks and the Paleogene granite. Wave-cut platform in the area is smaller and narrower relative to that of the northern coastal area. Most of the platforms in the area have little Quaternary sediment. The platforms except the Holocene terrace (1 st terrace) can be divided into three steps. The lowest platform (2nd terrace) has an altitude of 8-11 m. The broad middle one (3rd terrace) is 17 to 22 m high. The highest terrace (4th terrace) is a narrow and sporadic bench with an altitude of about 44 m high. The lowest terrace is correlated to the 2nd terrace of the northern area, which corresponds to the oxygen isotopic stage 5a. The uplift rate calculated from a graphic method is 0.19 m/ky. This low uplift is typical of an intra-plate, suggesting that the area is tectonically stable. The elevation of the platforms tends slightly lower from the north to the south in the survey area. The decreasing altitude of the platforms towards the south is interpreted to result from a local block tilting during the Latest Pleistocene. This also indicates that the eastern coast of the Korean peninsula has been suffering a subsidence to the south.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.6
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• pp.29-41
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• 2020

Wild pollinators provide important pollination services for crops. However, their geographical ranges and impact on pollination services have not been fully explored within the scope of Korean agricultural land. This study aims to identify spatial supply-demand mismatches across orchard fields in the context of assessing pollination service risk. We first used National Ecosystem Survey data and a species distribution model (MaxEnt) to develop the geographic range of each of 32 wild pollinators belonging to three families (Diptera, Hymenoptera, and Lepidoptera). We then summed the modeled presence probability of each species to obtain a measure of spatially explicit pollinator richness. This modeled richness, defined as pollination supply, was compared with the summed area of orchard fields at the municipal boundary level to identify areas with supply-demand mismatches. The study found that Lepidoptera showed the highest species richness (8.3±1.5), followed by Hymenoptera (4.3±0.8) and Diptera (3.5±0.8) species. Median orchard area was 1.5 ㎢ (range of 0-176.7 ㎢) among 250 municipal regions in South Korea. The municipal regions were divided into three categories (tertiles) of low, middle, and high pollination supply and demand according to, respectivley, average polliator richness and orhard area. Finally, we found that 55 municipal regions (accounting for 49% of national orchard land) potentially faced high risk of pollination deficits, 81 regions (48% of national orchard land) faced intermediate risk, and 63 regions faced low risk (3% of national orchard land). In conclusion, this study revealed significant mismatch between pollination supply and demand and developed risk assessment map will guide our future efforts on pollinator habitat conservation and monitoring to conserve crop pollination services.

• The Korean Journal of Zoology
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• v.18 no.3
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• pp.141-146
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• 1975

The purposes of this study were to investigate the frequencies of acatalasemia and hypocatalasemia in Korean population to compare with those of Japanese, Chinese and chiefly Taiwan population. The results obtained were as followings; 1. In south area of Korea, Jeonju, Gwangju, Busan and Daegu, a total of 3,629 individuals were tested. No acatalasemia was found but 0.26% of hypocatalasemia in Jeonju, 0% in Gwangju, 0.21% in Busan and 0.06% in Daegu were found. 2. The frequency of hypocatalasemia in south area of Korea was found to be lower than in middle area. 3. The frequency of hypocatalasemia in this study was similar to that of Chinese(in Taiwan) and higher than that of Japanese. 4. The reason of the geographical differences in the freqency of the hypocatalasemia was considered to be due to the natural selection. And the reason of the higher frequency of Korean population living in Japan was considered that originally the frequency of Korean population is higher, and the maintenace of this higher degree is obliged to the assortative mating beteen them.