• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.2
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• pp.88-99
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• 2007

Soil moisture is one of the essential components in determining surface hydrological processes such as infiltration, surface runoff as well as meteorological, ecological and water quality responses at watershed scale. This paper discusses soil moisture transfer processes measured at hillslope scale in the Gwangneung forest catchment to understand and provide the basis of stochastic structures of soil moisture variation. Measured soil moisture series were modelled based upon the developed univariate model platform. The modeling consists of a series of procedures: pre-treatment of data, model structure investigation, selection of candidate models, parameter estimation and diagnostic checking. The spatial distribution of model is associated with topographic characteristics of the hillslope. The upslope area computed by the multiple flow direction algorithm and the local slope are found to be effective parameters to explain the distribution of the model structure. This study enables us to identify the key factors affecting the soil moisture distribution and to ultimately construct a realistic soil moisture map in a complex landscape such as the Gwangneung Supersite.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.33-39
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• 2020

In order to cope with traffic accidents efficiently, the maximum number of traffic accidents, deaths and serious injuries that can occur during the day should be presented quantitatively. In order to examine the characteristics of traffic accidents in different regions, it was divided into the Seoul metropolitan area, Chungcheong area, Gyeongbuk area, Honam area, and Gyeongnam area and was suitable for the generalized extreme value distribution (GEV). The parameters of the GEV distribution were estimated by the L-moments, and the Anderson-Darling test and the Cramer-von Mises test confirmed the suitability of the distribution. According to the analysis, the maximum number of traffic accidents that can occur once every 50 years is 401 in the Seoul metropolitan area, 168 in the South Gyeongsang region, 455 in the North Gyeongsang region, 136 in the Chungcheong region and 205 in the South Jeolla region. Compared to the Seoul metropolitan area, which has a large population and car registration, the number of traffic accidents is relatively high due to the large area, mountainous areas, and logistics movement caused by the industrial complex.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.121-130
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• 2015

Identifying students' achievement level and reflecting it on educational policy making or instructional improvement by analyzing the results of nationwide standardized assessment is an integral part of accountability in education. On the basis of this premise, we analyzed the characteristics of National Assessment of Educational Achievement (NAEA) items for middle school science subject conducted from 2010 to 2013 by using the option response rate distribution curve, the fittest graph estimated from the response rate of correct/incorrect options by achievement score. Furthermore, we classified the type of option response rate curve in terms of correct and incorrect options. Results of the analysis of option response curve showed that five types of correct option response curve (S-shaped, J-shaped, straight-shaped, F-shaped, and step-shaped) and 4 types of incorrect option response curve (down-slope, flat, mound, and up-slope) were identified. The most common type of items was the combination of S-shaped correct option response curve and down-slope incorrect option response curve, which are considered as appropriate items to discriminate the students according to achievement level. Moreover, correct option response was found to be correlated with incorrect option response. Based on the results, we also discussed some implications on teaching-learning method and classroom assessment in science education.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.573-580
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• 2006

A sediment core from the Cheollipo arboretum ($36^{\circ}$ 47' 57'N, $126^{\circ}$ 09' 04') was studied for pollen analysis in order to reconstruct postglacial vegetational change and environmental changes around the central western region of the Korean Peninsula. The record shows four pollen assemblage zones: Zone CHL-I, Quercus stage (ca. 9,300$\sim$6,200 yr BP): zone CHL-II, Quercus-Pinus stage (ca. 6,200$\sim$4,600 yr BP); zone CHL- III, Pinus-Quercus stage (ca. 4,600$\sim$1,160 yr BP): zone CHL-IV and Pinus stage (ca. 1,160 yr BP-present). During the 9,300$\sim$8,500 yr BP, the early Holocene, researchers have guessed a piece of cool-temperate norihern/altimontane mixed coniferous and deciduous broad-leaved forest. Between 8,500$\sim$4,600 yr BP the Quercus dominated the landscape of study area and the established dates of this typical cool-temperate central/montane deciduous broad-leaved forest vegetation might be ca. 6500 yr BP, and then the Pinus developed around the site at ca. 5,700 yr BP. The abrupt increase of Pinus and NAP (non-arboreal pollen) after ca. 1,100 yr BP indicates the vegetation changes due to human activities. From the dynamics of the Chenopodiaceae pollen indicating salt marsh and freshwater pollen flora such as Typha, Trapa, Nymphoides and so forth, we suggest that the tidal flat was altered into freshwater lake around 6,500 yr BP.

• Journal of Conservation Science
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• v.31 no.1
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• pp.47-64
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• 2015

The excavated potteries and raw clays of the Bronze Age from the archaeological sites in the Cheonan-Asan area were studied on material scientific characteristics and homogeneity. Under the microscope, grainsize of the tempers in the potteries were distributed from less than 1mm to 10mm. Microtexture of the potteries showed various shapes and sizes of pores. In addition to the main minerals such as quartz, feldspar, mica, hornblende, chlorite and talc were found from the X-ray diffraction analysis of potteries, while talc was not found in the raw clay. Therefore, it was considered as an artificially added mineral. Firing temperature of the potteries, which did not contain chlorite, are assumed that they were baked below $850^{\circ}C$. On the other hand, the potteries which had mica and talc, are assumed that they were fired below $900^{\circ}C$. The geochemical characteristics of the potteries and raw clays showed very similar patterns, that means the potteries were produced by using the raw clay sources from each site.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.40-40
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• 2019

는쟁이냉이는 전국 각지 산지의 응달이나 물가에서 자생하는 여러해살이풀이다. 3월 경 눈을 뚫고나와 가장 이른 봄나물로 식용하기도 한다. 특유의 매운 맛이 있어 식용작물로 발전가능성이 높은 식물종이다. 따라서 본 연구는 는쟁이냉이 재배기술 정립을 위한 기초자료 수집의 일환으로 수행되었다. 차광에 따른 는쟁이냉이 생육특성을 비교 분석하기 위해 경북 봉화군 소재 국립백두대간수목원 양묘장 노지에 무차광, 40% 차광, 55%차광, 65%차광 처리구를 배치 후, 실험을 진행하였다. 생육특성의 비교를 위해 초장, 초폭, 엽 수, 엽길이, 엽너비, 엽병길이, SPAD 값 총 7가지 항목에 대해 생장기(6월), 휴면기(9월) 두 차례 측정하였다. 측정 결과, 모든 측정값이 차광구가 무차광구보다 높게 나타났다. 또한 무차광구는 6월 조사 이후, 7월 말까지 생장량이 줄어들다가 전량 지상부 고사가 발생하여 는쟁이냉이 재배를 위해서는 차광처리가 필수적으로 필요하다는 것을 확인할 수 있었다. 측정항목 중 초장, 초폭, 엽길이, 엽너비, 엽병길이는 차광율이 높을수록 증가하는 경향을 보였다. 그러나 엽록소함량을 추정할 수 있는 SPAD 값은 40% 차광구가 가장 높았고 55%차광구, 65%차광구에서는 오히려 감소하는 경향을 보였다. 또한 엽 수도 40% 차광구가 가장 높았다. 위 결과를 종합해볼 때, 는쟁이냉이 재배 시 55% 이상의 차광율을 적용하면 잎 자체의 크기 증대를 기대할 수 있으며, 40% 수준의 차광율을 적용하면 잎 수와 혁질의 잎을 생산할 수 있을 것으로 여겨진다. 다만, 본 실험은 는쟁이냉이 재배 생산량에 대한 부분에 집중하였고 상품화를 위해서는 품질에 관한 연구가 추가적으로 이루어져야 할 것으로 판단된다.

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.11-24
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• 2008

Stratified slope was formed on the SSE-facing slope in the southwest region of Haenam, South Korea. Field and laboratory investigations into the geomorphology and sedimentology of stratified slope deposit that is inactive. Outcrops of this deposit show an alteration of coarse debris-supported matrix and tiny debris-supported matrix layers. Sedimentological analysis(particle-size analysis) indicates that this deposit is not fluvial process or only gravitation like rock-fall. Many clasts and fine materials on the slope is supposed to be product by congelifraction under Pleistocene periglacial climatic environment. Also The processes responsible for the genesis of this deposit probably are to move downward by gelifluction and to remove fine materials by slope wash in thawing cycle and in situ debris congelifraction on gelifluction slope. Now It is impossible to account for the time range of genesis(diurnal, seasonal). In conclusion, this stratified slope formed in cold and humid periglacial environmental in pleistocene, therefore, this slope is a periglacial relic landform, indicates that in south korea there was a cold and humid paleo-climate such as periglacial environmen.

• Journal of Korean Society of Forest Science
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• v.112 no.3
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• pp.382-392
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• 2023

Recent reports have indicated a rapid increase in the frequency of sediment disasters due to climate change and other changes in the geological environment. Given this alarming situation and the recent increase in the frequency of land creep in Korea, systematic and efficient recovery and management of land creep areas is essential. The purpose of this study is to identify disaster vulnerability by conducting a physical exploration of land creep in San 4-1, Jayeon-ri, Gaegun-myeon, Yangpyeong-gun, Gyeonggi-do, and examine stability by identifying the overall geological structure of the affected ground. In addition, drilling surveys are conducted to verify the reliability of the measured data. The results of the study reveal that low specific resistance abnormalities are distributed in the upper part of the soil layer and weathering zone and that this section is a 50-120 m exploration line. It is also confirmed to be a low-hardness ground area where tensile cracks are observed. Therefore, there is a need for research focused on developing measures to reduce economic and social damage within the domestic context by continuously monitoring indicators of land creep and identifying land creep risks.

• Journal of The Geomorphological Association of Korea
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• v.17 no.2
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• pp.63-76
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• 2010

The Jangdo wetland is located on a very gentle slope of the mountain area in Daejangdo island, Shinan-gun, Korea, in which the area of the watershed is estimated at 147,000 m². The wetland has been regarded as a peat bog without any sedimentological evidence. This study was conducted to analyze the geomorphological and sedimentological characteristics of the wetland. The geographic information system (GIS) was used to analyze the drainage system, and field surveys were conducted to measure the range and depth of wetland deposits. The grain size analysis, organic matter determination, elements analysis and radiocarbon dating were performed on samples from the wetland. As a result, the wetland deposits were about 30 cm deep on average, the mean grain sizes ranged from 50 to 500 μm, and the average C/N ratio was 11.5. The portion of organic matter it contained was only 5~26%, which did not satisfy the peat standards. The radiocarbon ages from the wetland deposits range 180±50 ¹⁴C yr BP to modern, which indicated that natural and anthropogenic interferences including agricultural activities have continuously happened. We conclude that the Jangdo wetland is still in its infancy, not a steady state, so that it could be very sensitive to a small disturbance.

• Korean Journal of Heritage: History & Science
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• v.56 no.2
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• pp.206-220
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• 2023

In the royal publishing process of the Joseon Dynasty, the main species of wood used for woodblock printing was recorded as Jajak-mok. Although the name Jajak-mok may suggest Jajak-namu(white birch), it is presumed to refer to a different type of wood than Jajak-namu based on its recorded habitat and usage in historical documents. The aim of this paper is to clarify that during the Joseon Dynasty, the term Jajak-mok referred to Geojesu-namu (Korean birch), while Jajak-namu was called Hwa-mok(樺木). Additionally, this paper explores how the term Jajakmok eventually became the name of white birch, Jajak-namu, used today. In the mid-18th century, Japan used the character 樺(hwa) to refer to Beot-namu(Sargent cherry). As Japanese encyclopedias entered Joseon, the term Hwa-mok began to refer to both Beot-namu and Jajak-namu, which is also called Bot-namu. Since the pronunciation of Boet-namu and Bot-namu are similar, the two trees were eventually unified under the name Boet-namu. In the 20th century, the official names of three trees were established. According to notifications issued by the Ministry of Agriculture and Commerce of the Korean Empire in 1910 and the Governor-General of Chosen in 1912, Hwa-mok(white birch) was renamed asJajak-namu. In 1968, Beot-namu(Sargent cherry) retained its original name, and Jajak-mok(Korean birch) was remained . In modern Chinese character dictionaries, the meaning of 樺(hwa) is listed as "1. Beot-namu(Sargent cherry), 2. Jajak-namu(white birch)." From this, we can infer the historical background in which the names of these three trees were mixed up.