• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.2
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• pp.92-101
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• 2020

To prevent and mitigate damage to farms due to heavy snowfall, snow weight information should be provided in addition to snow depth. This study reviews four formulae regarding snow density and weight used in extant studies and applies them in Suwon area to estimate snow weight in Korea. We investigated the observed snow depth of 94 meteorological stations and automatic weather stations (AWS) data over the past 30 years (1988-2017). Based on the spatial distribution of snow depth by area in Korea, much of the fresh snow cover, due to heavy snowfall, occurred in Jeollabuk-do and Gangwon-do. Record snowfalls occurred in Gyeongsangbuk-do and Gangwon-do. However, the most recent heavy snowfall in winter occurred in Gyeonggi-do, Gyeongsangbuk-do, and Jeollanam-do. This implies that even if the snow depth is high, there is no significant damage unless the snow weight is high. The estimation of snow weight in Suwon area yielded different results based on the calculation method of snow density. In general, high snow depth is associated with heavy snow weight. However, maximum snow weight and maximum snow depth do not necessarily occur on the same day. The result of this study can be utilized to estimate the snow weight at other locations in Korea and to carry out snow weight prediction based on a numerical model. Snow weight information is expected to aid in establishing standards for greenhouse design and to reduce the economic losses incurred by farms.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.2
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• pp.68-75
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• 2017

Demand for dwarf mondo grass (DMG; Ophiopogon japonicus 'Nanus') as an ornamental garden plant is expected to grow in the future. The purpose of this study was to investigate the levels of shade tolerance and ground cover by growing DMG under a variety of shade conditions for 18 months (May 2015~October 2016). DMG plants grown in bare ground for 3 years in Jangheung-gun, Jeonnam were used for testing. In an experimental site created in Naju city in Jeonnam, the DMG was planted in planters ($70cm{\times}70cm{\times}24cm$) and covered with a shading curtain to block natural light. Shaded conditions were then arranged under different levels of shade (0%, 55% and 75%). When the plants were grown, growth (leaf size, the number of leaves, fresh weight and dry weight) and ground coverage of DMG were analyzed. According to the results, DMG growth in terms of leaf size and the number of leaves was statistically higher under zero shade (full sunlight), when compared to other shaded conditions. DMG's fresh and dry weights were significantly greater under 0% and 55% shade, compared to those under 75% shade. The degrees of shade tolerance required for normal growth of DMG were found in the range of 0~50%, meaning that more than 50% shade may decrease plant growth. There were no statistical differences in ground coverage rates of DMG under different levels of shade. When 220 tillers were planted per $1m^2$ of plot, up to 80% of the area was covered by DMG after 18 months. Since DMG requires nutrient-rich soil to grow, sufficient nitrogen fertilizers are proposed to accelerate the ground cover of DMG. As DMG remained alive over the winter in the experiments, this study also suggests that DMG can be planted in the southern temperate region.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.637-644
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• 2016

This paper is a follow-up to previous papers entitled, "Development of Tunnel-Environment Monitoring System and Its Installation" I [1] and II [2]. The target tunnel of these studies is the Solan Tunnel, which is a loop-type, single-track, 16.7-km-long tunnel located in mountainous terrain and passing through the Baekdudaegan mountain range. It is an ordinary railway tunnel designed for both freight and passenger trains. We analyzed the environmental conditions of the tunnel using temperature and humidity data recorded over approximately one year. The data were recorded using the Tunnel Rough Environment Measuring System (TREMS), which measures environmental data in subway and high-speed train tunnels and is installed in three locations inside the tunnel. Previous studies analyzed environmental conditions inside tunnels located in or near a city, whereas the tunnel in this study is located in a mountainous area. The tunnel conditions were compared with those measured outside the tunnel for each month. Hourly changes during summer and winter periods were also analyzed, and the environmental conditions at different locations inside the tunnel were compared. The results are widely applicable in studies on the thermal environment and air quality of tunnels, as well as for computer analysis of tunnel airflow such as tunnel ventilation and fire simulations.

• Journal of Sericultural and Entomological Science
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• v.52 no.2
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• pp.123-128
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• 2014

We carried out an ecological survey for Ceratovacuna japonica, which lives in bamboos, at the experimental field of National Academy of Agricultural Science, Suwon and the several natural fields in Korea from 2010 to 2011. The releasing methods of C. japonica on Pseudosasa japonica was more effective at the brushing-off method than the pining-attached method. The successful rate of releasing was the highest at green house than others such as at outdoor, vinyl green house and in a insects net conditions. The survival limit of C. japonica was closely associated with the lowest temperature ($-10^{\circ}C$) of vegetative limit of P. japonica for over wintering because of two fields of Ilsan lake park and Guri ecological park showed falling down below $-15^{\circ}C$ two times in January. It provides for a reasonable distribution information of C. japonica that is restricted to south of Han River. However, the middle of Korea has rarely fallen down below $-10^{\circ}C$. Therefore, we consider that a successful rearing of C. japonica may be the most suitable in green house condition to overcome winter period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.500-507
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• 1998

Using a sledge net, the benthic amphipods were taken over one cycle of the neap and spring tides in January 1993 at the sandy shore surf zone of Dolsando, southern Korea. From these samples, we investigated the diel and tidal effects on the intraspecific zonation of Pontogeneia rostrata. The density of p. rostrata was higher during neap tide than spring. Of three categories (adult males and females and juveniles), juveniles and males attained to its highest density during neap and spring tides, respectively. Length- frequency data show that the high mortality of juveniles seemed to occur in winter. In the surface at night, it is significant that juveniles were significantly more abundant during neap tide than spring, whereas both adult males and females were more abundant during spring tide than neap. This suggests that the vortical migration patterns of juveniles and adults vary with the type of tides. During flood of spring tide, more than $90\%$ of population collected at the area above the mean sea level (MSL) were adults. With a decrease of female/male ratio, size of males increased there but that of female did not change, indicating an active migration of large males. This behavior can provide an extension of distribution area far large males, and also give a competitive advantage to large male against small one for mate and feeding. Although adult p. rostrata was collected at 100 cm above MSL at night during spring tide, a major portion of population as usually present on the shore below MSL. The center of zonation was restricted from 50 cm to 250 cm below MSL.

• Journal of agriculture & life science
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• v.43 no.1
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• pp.35-41
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• 2009

This study was conducted to analyze the phenotypic trends and environmental factors affecting the following carcass traits : slaughter weight, backfat thickness and carcass grade, in 1,251,572 commercial pigs for 7 years from 1999 to 2005. The average slaughter weight of female, male and barrow were $82.97{\pm}0.008$ $82.00{\pm}0.090$ and $82.79{\pm}0.008$, respectively. The average backfat thickness of female, male and barrow were $19.27{\pm}0.006$, $15.99{\pm}0.072$ and $22.49{\pm}0.006mm$, respectively. The slaughter weight tended to increase over the slaughter years, for backfat thickness remained, even though a significant drop of backfat thickness on 2002($18.75{\pm}0.027$). The slaughter weight was significantly higher in winter($83.29{\pm}0.032$), while the backfat thickness was significantly lower in summer($19.10{\pm}0.026$). The carcass grade A increased from 2000 to 2003, but decreased slightly after 2003. On the contrary, the carcass grade B decreased from 2000 to 2003, but increased slightly after 2003.

• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.85-94
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• 2008

This study is to construe spatio-temporal characteristics of temperature in cities and changes of climatical regions in analyzing a change of Korea Peninsular climate. We used daily mean air temperature data which was collected in South and North Korea for the past 34 years from 1974 to 2007. We created temperature map of 500m resolution using Inverse Distance Weight in application with adiabatic lapse rate per month in linear relation with height and temperature. In the urbanization area, the data analyzed population in comparison with temperature changes by the year. An annual rising rate of temperature was calculated $0.0056^{\circ}C$, and the temperature was increased $2.14^{\circ}C$ from 1974 to 2107. The south climate region in Korea by the Warmth index was expanded to the middle climate region by the latitude after 1990s. A rise of urban area in mean temperature was $0.5-1.2^{\circ}C$, Seoul, metropolitan and cities which were high density of urbanization and industrialization with the population increase between 1980s and 1990s. In case of North Korea, Cities were Pyeongyang, Anju, Gaecheon, Hesan. A rise in cities areas in mean temperature has influence on vegetation, especially secondary growth such as winter buds of pine trees appears built-up area and outskirts in late Autumn. Finally, nowaday we confront diverse natural events over climatical changes, We need a long-term research to survey and analyze an index on the climatical changes to present a systematic approach and solution in the future.

• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.751-761
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• 2019

Mt. Baekdu, Mt. Aso, Mt. Sakurajima, Mt. Kikai and etc are distributed around the Korean Peninsula. Recently signs of eruption of Mt. Baekdu are increasing, raising concerns over possible damage to volcanic ash from seasonal winds during the winter eruption. Therefore, detailed procedures for investigation and countermeasures for volcanic ash spread and damage are required. But the standards for the warning and alarm signal of volcanic ash presented by Korea Ministry of Government Legislation are vague, with "when damage is expected" and "when serious damage is expected". In this study, to analyze the damage threshold and to apply the cases of overseas damage to the country, a survey was conducted on the establishment of domestic spatial information by public institutions with public confidence. As a result of the investigation of damage from volcanic ash overseas, the details of the damage cases were different depending on the type of life or income sources of each country. Therefore, instead of applying the volcanic ash damage cases abroad in Korea, spatial information analysis was performed to reflect domestic social and natural characteristics. In addition, we selected the areas to be considered in the event of volcanic ash damage in Korea. Finally, domestic volcanic ash damages should be classified as health, residential, road, railroad, aviation, power, water, agriculture, livestock, forest, and soil. When establishing the volcanic ash alarm optimized for Korea in the future, overseas volcanic ash damage cases and domestic spatial information construction in this study will be helpful in policy establishment.

• Korea and Global Affairs
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• v.3 no.2
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• pp.87-130
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• 2019

This paper aims to analyze the recent progress(current situation) and tasks of arms control in North and South Korea. To this end the paper is composed of 5 chapters titled instruction; recent progress(current situation) of arms control in South and North Korea; constraints and tasks of arms control on the Korean peninsula; and conclusion. One of the most important tasks for the establishment of a peace structure for the coexistence of the Korean people in the 21st century is the realization of military control in order to resolve the acute military confrontation situation and mutual threats. With the 2018 PyeongChang Winter Olympics, the North-South summit and the subsequent talks for peace and denuclearization on the Korean Peninsula, the North Korea-US summit, and subsequent talks are creating conditions for trust building and arms control between the two Koreas. The military trust between the two Koreas and operational arms control are being achieved through the declaration of the April 27 Panmunjom and the 'Military Agreement for the Implementation of the Panmunjom Declaration.' However, since there are constraints on the control of arms control, such as the persistence of hostility and distrust of the two Koreas, the defense treaty between the two Koreas and neighboring countries, the competition of neighboring countries and the complex interests of the Korean peninsula, Trust Building is important. We should resolve the issue of arms control between the two Koreas, taking into account the trend of international arms control over the internal and external dynamics of the Korean peninsula gradually and carefully, with a vision of long-term unification security.

• The Journal of Korean Society for School & Community Health Education
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• v.4
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• pp.79-95
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• 2003

This dissertation aims to analyze various safety accidents taking place during physical education class according to physical education teacher's value orientation, to identify teacher's value orientation that can minimize safety accidents, and to provide basic materials for safe and smooth class management. For this purpose, data have been collected from 261 physical education teachers at some middle and high schools in G City in Kyung-Ki Province and Busan Metropolitan City. The materials were treated as follows: The variables on demographic characteristics of physical education teachers are determined by t-test ; The analysis of one-way ANOVA and relationship between value orientation and safety accident prevention activities was conducted through Pearson's linear correlation analysis and multiple regression; The analysis of the relationship between value orientation and actual conditions of safety accidents was conducted through logistic regression. First, there is almost no awareness difference of physical education teachers' value orientation according to demographical variables. The value orientation physical education teachers consider to be the most important is, however, mainly 'mastery of disciplinary lesson.' There is a statistically significant difference in safety accident prevention activities according to demographical variables. Teachers' focuses in class contents showed a significant difference according to teaching experience and working area, while the dependency on facility has a significant difference according to teaching experience and school type. Second, there is no correlation between physical education teacher's value orientation and safety accident prevention activities because there is virtually no statistically significant difference between them. It means that safety accident prevention activities are not related with on which teachers place emphasis among mastery of disciplinary lesson, social reconstruction, self-realization, ecological integration and value orientation on learning process. Third, the analysis of safety accident prevention activities according to physical education teachers' value orientation revealed that the lower value orientation in social reconstruction is, the more safety accidents teachers experience. It is also found that crashes among students, ball games and leg injuries are inter-related with social reconstruction in value orientation, over-motivation and unskilled motor function ; athletic sports with value orientation on learning process and safety prevention training ; unskilled motor functions with value orientation in ecological integration and disobedience to teacher's directions ; winter accidents with mastery of disciplinary lesson in value orientation. In conclusion, the research indicates that physical education teacher's value orientation according to demographical variables didn't show any significant difference, while one according to safety accident prevention activities showed significant difference. Besides, physical education teachers' value orientation is not related to safety accident prevention activities, but the relationship between value orientation and actual conditions of safety accidents showed correlations according to each variable. Especially, teachers with lower value orientation in social reconstruction experienced more safety accidents. Therefore, physical education teachers can manage physical education class more safely with more emphasis on value orientation in social reconstruction.