• The Journal of the Petrological Society of Korea
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• v.19 no.1
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• pp.31-49
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• 2010

Nearly NS-trending Fe-Ti ore bodies intermittently occur in the Hadong anorthosites, south Korea, irrespective of the rock types of the anorthosites. In order to determine their occurrence mode and deformation history, we collected the features of occurrence and geological structures in the field, petrographic features using thin sections of the principal constituent rocks, and geochemical data of ilmenites in the ore body using electron probe microanalysis. Fe-Ti ore bodies examined in this study are divided into two types: dike- and lamina-types. It is steadily supported that the dike-type has intruded into the anorthositic rocks after their emplacement and solidification. And the laminar-type is probably a result of the mylonitization and transposition of the dike-type ore bodies parallel to the shear planes, due to later strong dextral ductile shearing. In the meantime, the Fe-Ti ore bodies have experienced the stronger dextral shearing in the more northern part of the study area, i.e. Cheongryong-ri, Wolhoeng-ri, Jonghwa-ri, and Jayangri and Baekun-ri in ascending order of its strength, together with the less content of $TiO_2$. All ilmenites of the ore bodies have very similar chemical composition, as pure ilmenite of 52~55 wt.% in $TiO_2$ content, irrespective of the occurrence mode and degree of later ductile shearing of the ore bodies. And they didn't experience to exsolve into magnetite. The structural data indicate that the Hadong anorthosites have deformed by NNE-trending folding, intrusion of the Fe-Ti ore bodies, NNW~NNE-trending dextral ductile shearing, NW~NNW-trending sinistral semi-brittle shearing, and intrusion of NNE~NE-trending mafic dykes in descending order of chronology after the formation of foliation of the anorthositic rocks. The foliation is interpreted as a result of the accumulation of crystals that settle out from the magma by the action of gravity.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1254-1268
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• 2009

In 1998, because of the economic crisis called IMF Crisis in Korea, Kyungbu high speed railway project could run by modifying the original plan to open it as a 1st phase only by utilizing the existing railway lines from Seoul to Siheung and the other one from Daegu to Pusan. The modified plan includes that the line from Daegu to Pusan will be constructed as a second phase in next time. Starting railway operation with the changed plan, the combined application operation of high speed rail, passenger rail and freight rail was caused partly from Seoul to Siheung to run into capital area. As a result, the opinion for additional railway line construction is insisted continuously because the operation volume of passenger rail was forced to be reduced, the service quality of it was decreased and it became difficult to add new high speed services. Moreover, with regard to Honam high speed rail, the new construction plan of station in Kangnam metro area as a basement station for starting from Suseo was changed to the plan of turning out at Osong because of the economic effectiveness and this kept resident people in Kangnam metro area and southern Kyungki area unable to get the opportunity of high speed rail service benefit. After beginning of Kyungbu high speed railway operation, national transportation system developments are focused on high speed rail, and when the second phase construction of Kyungbu high speed rail, beginning operation of Kyungjeon line, Jeolla line double track construction, Honam high speed rail in 2014, is completed, the demand for high speed rail will be increased and it is unavoidable to make Kwangmyung station as a basement station and to reduce the number of passenger rail operation. At this moment, it is valuable to consider adding the railway line capacity in capital area to improve the transferring service for citizen who live in area without Kyungbu high speed rail station and to expand the service area from Kangbuk to Kangnam and southern Kyungki area. Accordingly, in this paper, the effective rail operation method, facility plan and the other issue to be reviewed for increasing capital high speed railway lines will be mentioned.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.76-88
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• 2011

The flora of vascular plants in the mountains located in the Uiryeong-gun area, in the South province of the Korean Peninsula, such as Jagul-san(897.1 m), 676 Highland(676 m), Byeokhwa-san(522 m), and the Bangeo-san(530.4 m), was investigated between April 2008 and August 2009. These investigations found 580 taxa consisting of 496 species, 1 subspecies, 77 varieties, and 6 forms, found within 319 genera under 103 families. The count totaled at 744 taxa(16.2% of all vascular plant taxa in Korea), which was made up of 648 species, 3 subspecies, 81 varieties, and 12 forms, found within of 362 genera under 109 families, when voucher specimens from the previous research studies were added. Forests of the investigated areas were generally composed of mixed Pinus densiflora and Quercus sp. The areas with comparatively excellent vegetation were the valley neighboring Baekun-sa(temple) (in the eastern slope of Mt. Jagul-san), the southwest slope of Mt. 676 Highland, the eastern slope of Mt. Byeokhwa-san, and the northern slope of Mt. Bangeo-san. 10 families were collected in abundance: Compositae, Graminae, Leguminosae, Liliaceae, Rosaceae, Cyperaceae, Labiatae, Polygonaceae, Ranunculaceae, and Violaceae these families made up 50% of all collected taxa. 19 taxa were endemic to the area, including Salix hallaisanensis H.Lev, S. koriyanagi Kimura, Aconitum austrokoreense Koidz, A. pseudolaeve Nakai, Clematis trichotoma Nakai, Thalictrum uchiyamai Nakai, Stewartia pseudocamellia Maxim, Philadelphus schrenkii Rupr., Lespedeza ${\times}$ robusta Nakai, Vicia chosenensis Ohwi, Euonymus trapococca Nakai, and Angelica cartilagino-marginata var. distans(Nakai) Kitag. Eight of the taxa were rare and endangered plants, as designated by the Korea Forest Service, including Jeffersonia dubia(Maxim.) Baker & S. Moore and Viola diamantiaca Nakai. 38 taxa of alien plants were found. Vegetation of the surveyed areas falls in the South province of the Korean Peninsula. Of all the taxa collected, 463 taxa(10.06% of all vascular plants in Korea) are considered useful plants, 231 taxa are edible, 193 taxa have medicinal uses, 65 taxa are used ornamentally, 234 taxa are important forage, 3 taxa are used as an industrial raw material, 17 taxa are used for timber, 18 taxa contain useful dyes, and 7 taxa are used for fiber.

• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.99-105
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• 2020

Migratory birds use a variety of breeding and wintering sites, and it is particularly important to understand more information on breeding and feeding sites for the conservation and management of endangered species. Black-faced spoonbills (Platalea minor) are an international endangered species distributed in East Asia. The majority of black-faced spoonbills breed on uninhabited islets off the west coast of the Korean Peninsula during the breeding season, and they are distributed in East Asia such as Taiwan, Hong Kong, southern China, Japan, and Jeju island during the winter season. In this study, we used a wild animal location tracking system to analyze and compare home ranges of three black-faced spoonbills spending the post-fledging stage in Gujido islet in Incheon and Chilsando islet in Yeonggwang each in 2015. The tree black-faced spoonbills in Guji islet showed a home range in coastal areas in Hwanghaenam-do and Gangneung-gun. The home range size (mean±SD) was estimated to be 425.49±116.95 ㎢ using 100% MCP, 43.61±18.51 ㎢ using KDE 95%, and 7.46±3.68 ㎢using KDE 50%. The tree black-faced spoonbills in Chilsando islet showed a home range in the Baeksu tidal flat and the Buan Saemangeum area with a size of 99.38±55.29 ㎢ using 100% MCP, 19.87±6.05 ㎢ using KDE 95%, and 1.16±0.53 ㎢ using KDE 50%. The figured indicated that the tree black-faced spoonbills breeding in Gujido islet had a wider home range than those breeding in Chilsando islet. During the post-fledging stage, the home ranges of black-faced spoonbills were mostly breeding in mudflats. Therefore, it is necessary to minimize human intervention, such as the construction of roads and structures and the human access, to protect the habitats during the period.

• The Journal of the Petrological Society of Korea
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• v.21 no.4
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• pp.385-396
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• 2012

Jeju island is the biggest volcanic island in Korea and there are over 455 Quaternary monogenetic volcanoes, of which approximately 373 volcanoes(82.0%) are cinder cones. Other volcanic forms in the island include sharp-pointed lava cone without crater(9 volcanoes; 2.0%), shield volcanoes(27 volcanoes; 5.9%), tuff rings(17 volcanoes; 3.7%), tuff cones(3 volcanoes; 0.7%), a maar(1 volcano; 0.2%) and lava domes(25 volcanoes; 5.5%). The monogenetic volcanoes include 15 small nested cinder cones(aloreum). The monogenetic volcanoes are more abundant in the eastern part of the island than in the western part. If the main cause of the weathering such as precipitation affected the shape of the monogenetic volcanoes, more monogenetic volcanoes(BC, CC, DC, etc.) are supposed to be present in the southern part that have more precipitation than in the northern part. But the distribution of the monogenetic volcanoes shows no difference between the southern and the northern parts. So we suggest that the difference of the climatic conditions did not affect the distribution or the shape of cinder cones. Tuff rings, tuff cones and a maar are distributed beneath the island or in the low-altitude areas along the shore although cinder cones are distributed in the interior of the island. This means that the volcanic activity which formed the monogenetic volcanoes resulted from either phreatomagmatic eruption or magmatic (hawaiian or strombolian) eruptions depending on the reaction with water (underground water or shallow waters). The distribution of the monogenetic volcanoes according to the altitude shows that 253(55.6%) volcanoes occur in low-lying coastal areas at an altitude below 300 m, 110(24.2%) in a middle mountainous area at an altitude between 300~600 m and 92(20.2%) in a high mountainous area at an altitude above 600 m. So more than half of monogenetic volcanoes are distributed in low-lying coastal areas.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.764-772
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• 2015

This study was conducted to investigate food safety management practices at children's foodservice facilities and evaluate the effect of visiting education by Center for Child-care Foodservice Management (CCFSM) for food safety improvement. The subjects of evaluation included child care centers (84.3%), kindergartens (7.8%), and community child centers (7.8%). Facilities by foundation types were private (70.6%), public (19.6%), and corporation (9.8%). The average score of food safety evaluation was 84.09 points. The total score of food safety evaluation of community child center was significantly lower than that of child care center and kindergarten (p<0.01); and the total score of public facilities was higher than that of private facilities. Furthermore, 35.9% of evaluation items showed performance higher than 90%, while 15.4% showed performance less than 60%. The item with lowest performance was 'washing and disinfection of fruits and vegetables (26.5%)'. Results of one-way ANOVA of food safety evaluation score by the frequency of visiting education indicated that the evaluation score of the third session significantly increased from the first and second sessions. In addition, the result of two-way ANOVA showed that both foodservice type (F=21.730, p<0.001) and the frequency of visiting education (F=7.968, p<0.001), and both foundation type (F=31.387, p<0.001) and the frequency of visiting education (F=7.507, p<0.001) affected the total food safety evaluation score. There were significant differences in result scores according to the number of meal served (F=17.133, p<0.001) and the frequency of food safety evaluation (F=17.065, p<0.001). In conclusion, visiting education of children's foodservice facility showed significant effect on the improvement of food safety level.

• Korean Journal of Medicinal Crop Science
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• v.3 no.1
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• pp.1-4
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• 1995

To determine the optimum sowing time and nursery period in Perilla frutescens in the southern areas of Korea, perilla frutescens cv. red Perilla local cultivar was grown under three different sowing dates and nursery periods. The blooming period of the area which was sown on the seedbed in Apr.10 and carried out the growing seedling in 30days is Aug. 12 and it is two days earlier than that of the area, Aug.14, sown on the seedbed in Apr. 20 and carried out the growing seedling in 30days of the same month and it is also six days earlier than that of the area, Aug.18, sown on the seedbed in April 30 and conducted the growing seedling in the same date. The stem lengths are 135cm,131cm and 125cm respectively and the number of branches are 26.4, 25.3 and 23.6 respectively. The fresh weight of stem and leaf at the area sown on the seedbed in Apr.10 and conducted the growing seedling in 30days with the width of leaf over 5cm in the middle of Aug. and at the beginning of Sep. is 2,476kg/10a and it shows more increase of 172kg than that of fresh weight of stem and leaf with 2,304kg/10a which was sown on the seedbed in Apr.20 and earned out the growing seedling in 30days, and it also shows more increase of 411kg than that of fresh weight of stem and leaf with 2,065kg/10a at the area sown on the seedbed in April 30 and con­ducted the growing seedling in the same date, The fresh weight of seeds are 609.5kg/10a,509.3kg/10a and 463.2kg/10a respectively and $100.2{\sim}146.3kg$ is more increased. Therefore, the seedling period of the proper seedbed for high yield bumper crop of perilla frutescens for exporting to Japan is April 10 and the number of days for seedling is 30 days.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.161-169
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• 2012

The RCP 8.5 scenario based temperature outlook (12.5 km resolution) was combined with high-definition gridded temperature maps (30 m grid spacing) across the Korean Peninsula in order to reclassify the cold hardiness zone for winter barley, a promising grain crop in the future under warmer winter conditions. Reference maps for the January minimum and mean temperature were prepared by applying the watershed-specific geospatial climate prediction schemes to the synoptic observations from 1981 to 2010 across North and South Korea. Decadal changes in the January minimum and mean temperatures projected by a regional version of RCP8.5 climate change scenario were prepared for the 2011-2100 period at 12.5 km grid spacing and were subsequently added to the reference maps, producing the 30 m resolution temperature surfaces for 9 decades from 2011 to 2100. A criterion for threshold temperature to grow winter barley safely in Korea was applied to the future temperature surfaces and the resulting maps were used to predict the production potential of 3 cultivar groups for the 9 future decades under the projected temperature conditions. By 2020s, hulled barley cultivars could be grown safely at the southern part of North Korea as well as the mountainous Gangwon province. Furthermore, most of South Korean rice paddies will be safe for growing naked barley after harvesting rice. Also, dual cropping systems such as 'winter-barley after rice' could be possible at most of the North Korean rice paddies by 2040s. Additional grain production in North Korea could increase up to 4 million tons per year if dual cropping systems can be fully operated, i.e., winter barley after rice at all lowlands and winter barley after maize or potato at all uplands.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.143-151
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• 2010

The impact of climate change on rice plants in Gangwon province was examined by comparing the climatic conditions during the recent 10 years (2000~2009) with those of normal (1971~2000) years, and by evaluating the rice plant responses. The daily mean air temperature increased by $0.5^{\circ}C$ while the daily range decreased by $0.1^{\circ}C$ as compared with the normal years. During the main rice growing period in field (from June to September) precipitation increased from 900 to 1,051mm and sunshine hours decreased from 704 to 619 hours. The respiration consumption effect during the rice growing period increased by 0.07 as a result of increased air temperature and reduced sunshine hours. The optimum heading date (determined by the mean air temperature for 40 days after the heading) was delayed in Chuncheon, Hongcheon, Wonju, and Gangneung compared with the normal. The maximum climatic yield potential based on mean temperature and sunshine hours for 40 days after the rice heading decreased by 94 kg/10a mainly due to the decrease in sunshine. The mean air temperature for 40 days after the rice heading from 1999 to 2009 in Chuncheon, Cheorwon, and Gangneung was generally above $22^{\circ}C$ implying that yield and quality of rice can be reduced. Therefore, it is necessary to delay the heading date by planting mid- to late-maturing varieties or by changing the transplanting date in order to produce high quality rice and to maintain rice productivity. In addition, it is also important to develop or select cultivars suitable to changing climate for each region in Gangwon province.

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.191-202
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• 2007

To identify the detailed attenuation structure in the southern Korean Peninsula, a numerical test was conducted for the Q tomography inversion to be applied to the accumulated dataset until 2005. In particular, the stochastic pointsource ground-motion model (STGM model; Boore, 2003) was adopted for the 2D Q tomography inversion for direct application to simulating the strong ground-motion. Simultaneous inversion of the STGM model parameters with a regional single Q model was performed to evaluate the source and site effects which were necessary to generate an artificial dataset for the numerical test. The artificial dataset consists of simulated Fourier spectra that resemble the real data in the magnitude-distance-frequency-error distribution except replacement of the regional single Q model with a checkerboard type of high and low values of laterally varying Q models. The total number of Q blocks used for the checkerboard test was 75 (grid size of $35{\times}44km^2$ for Q blocks); Q functional form of $Q_0f^{\eta}$ ($Q_0$=100 or 500, 0.0 < ${\eta}$ < 1.0) was assigned to each Q block for the checkerboard test. The checkerboard test has been implemented in three steps. At the first step, the initial values of Q-values for 75 blocks were estimated. At the second step, the site amplification function was estimated by using the initial guess of A(f) which is the mean site amplification functions (Yun and Suh, 2007) for the site class. The last step is to invert the tomographic Q-values of 75 blocks based on the results of the first and second steps. As a result of the checkerboard test, it was demonstrated that Q-values could be robustly estimated by using the 2D Q tomography inversion method even in the presence of perturbed source and site effects from the true input model.