• Journal of Life Science
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• v.20 no.9
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• pp.1353-1357
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• 2010

Quantification of the ecosystem respiration is essential in understanding the carbon cycling of natural and disturbed landscapes. Soil respiration and some environmental factors which affect soil respiration were investigated in a Larix leptolepis plantation inKongju, Korea. Soil respiration was measured at midday of the $15^{th}$ and $30^{th}$ day of every month from May to December in a non-cutting area (Control) and a cutting area (Treatment) with IRGA Soil Respiration Analyzer. Throughout the study period, average soil temperature and water content were $23.3{\pm}0.5^{\circ}C$ and $27.76{\pm}7.12%$ for control, and $25.9{\pm}3.1^{\circ}C$ and $24.55{\pm}5.12%$ for treatment, respectively. There was a positive correlation ($R^2$=0.8905) between soil respiration and soil temperature in the study area. However, there was no significant correlation between soil respiration and soil moisture ($R^2$=0.4437). The seasonal soil respiration increased in the summer and decreased in the winter. In August, maximum soil respirations in the control and treatment areas were $0.82{\pm}0.13$ and $1.32{\pm}0.10$ $gCO_2{\cdot}^{-2}{\cdot}r^{-1}$, respectively. Total amounts of $CO_2$ evolution in the control and treatment areas from May to December in 2008 were 2,419.2 and 3,610.8 $CO_2g{\cdot}m^{-2}$, respectively. The amount of soil respiration in the treatment area was 49.3% greater than in the control. Increased soil respiration in the treatment area may be due to increased soil temperature, which drives increased microbial decomposition. According to our present investigation, forest cutting will increase the atmospheric $CO_2$ by increasing soil respiration.

• Journal of Environmental Policy
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• v.11 no.4
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• pp.3-37
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• 2012

In perspective of biodiversity conservation and protected areas (PAs), the aims of the study are to review the mid-long term national plans, which deal with national territory and environment in Korea, and to find out the way to improve this issue. Key issues were drawn by referring "Biodiversity 2011-2020 Strategic Targets" and "Protected Area Decision" in CBD CoP-10 and 7 National comprehensive or basic Plans were reviewed. Quoting Biodiversity 2011-2020 Strategic Target 5, "By 2020, the rate of loss of all natural habitats, including forests, is at least halved and where feasible brought close to zero, and degradation and fragmentation is significantly reduced", most of national plans included various methods such as "No Net Loss of Green", "No Net Loss of Wetlands", and so on. Regarding the target 11, "By 2020, at least 17% of terrestrial and inland water, and 10% of coastal and marine areas, ecologically representative and well connected systems of PAs and other effective area-based conservation measures, and integrated into the wider landscape and seascapes", 15% by 2015 was set up as a target of total PAs in Korea and 13% by 2015 or 2020 was set up as a target of coastal and marine PAs. CBD CoP-10 Decision X/31 (Protected Areas) invites parties to develop a national long-term action plan for the implementation of PoWPA and describes 10 issues that need greater attention. National action plan for the implementation of PoWPA doesn't be mentioned at any national plans even PoWPA. Regarding the 10 issues, most of issues were well reflected within various national plans, however there is still a need to improve the details and corelation between plans. Particularly, in terms of management effectiveness evaluation (MEE), there was no national plan to directly deal with MEE even though CBD invites parties to work towards assessing 60% of the total PAs by 2015. Based on the review results, below 4 items were suggested; (1)"The Comprehensive Plan of the National Territory" needs more attention on the Biodiversity Conservation and PAs, (2)Consider to establish "National PA System Plan" embedded into "the Comprehensive Plan of National Environment", (3)Establish a "National Action Plan for the implementation of PoWPA", (4)Improve the National Plans through linking with Biodiversity 2011-2020 Strategic Targets and relevant PA key issues.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.4
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• pp.62-77
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• 2012

This study aimed to investigate the Confucian-oriented agriculture phase of the Joseon Dynasty, which was reflected at the palaces, by analyzing constructional aspects and spatial characteristics of farmlands at the palace rear gardens. The objective sites were the rear gardens of Gyeongbok Palace, Changkyung Palace, and the outside of Sinmoomoon(神武門) This study was based on literature reviews. The farmlands at the palace rear garden were constructed to self-estimate the year's harvest condition within the palaces. It was a part of the agriculture encouragement policy on governing the group of Joseon like publishing the Nongsajiksul(農事直說) and establishing the Chingyeongnye(親耕禮: king's own cultivation ceremony) and Kikokje(祈穀祭: the rite of praying for grain). In addition, farmlands of the rear garden were operated from the beginning of the state almost until the Japanese colonial era. The results were summarized as follows: First, Gyeongbok Palace rear garden's farmland which begin at the reign of Sejong(世宗) existed at the present Hyangwonji(香遠池) area. It was constructed in order to check the advanced agricultural technologies. The rear garden's farmland in Changkyung Palace, which was executed during the reign of Seongjong(成宗), was constructed right after the initial Chingyeongnye of the Joseon Dynasty. Therefore, it might be understood as the context of the king's own cultivation of the Jeokjeonchinkyung(籍田親耕). Injo(仁祖) dug for farmland in the ground of the Gyemgdeok Palace(慶德宮) though there was some stay palace, when his stay dragged out for too long. This bespeaks that those farmlands at the palace rear gardens were of great importance in the Joseon political history. The farmland near Gyeongnongjae(耕農齋), which was made during the reign of Gojong(高宗), inherited predecessor's walks of the promoting agriculture and exhibited spatial compositions such as the rear garden's farmland at Changkyung Palace. Secondly, irrigation, its water systems, the name of observatory to study farming[觀耕臺] and location requirements for farmland had something in common. It was assumed as universal forms of physiocracy-space in the Joseon Dynasty. In this study, by considering aspects of operating about vegetable garden managed by eunuchs and of the orchard in palace to cultivate fruits for national ceremonies, it could be assumed that landscape architecture of royal palace in the Joseon Dynasty did not only focus on solemnity, orderliness and fanciness but also on the practical and productive which was helpful in life. In addition, the diverse activities of productive landscape architecture led by the royal family in palaces, and the initiatively tested advanced agricultural technologies by the king were considered as an aspect of the Korean traditional specific royal palace landscape architecture. That is considered sole landscape not only to love of the people but also the 'agriculture-first' principle which were absent from other nations.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.12-23
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• 2019

The purpose of this study was to develop and study an experiential natural education program that could emphasize the importance of the natural environment by providing natural experience opportunities using the natural resources of the urban forest parks using Youngheung Park in Suwon, Gyeonggi Province as a target site. The research target was limited to Suwon Yeongheung Park, which had the potential to become a place for education, where urban forest conservation and sustainable use already coexist. The natural education resources derived by surveying and analyzing the basic environment and the ecology of plants and animals in Suwon Yeongheung Park were organized to establish program goals, directions, and themes. Suwon Yeongheung Park is a water-rich forest that forms an ecological system of wetlands, including rice paddies, muknon wetlands, and dungbun, near a valley area. The U-shaped walkway was smoothly formed along the ridge and includes Doran-gil, which is among the Palochrome Road, designated by the city of Suwon. The soil is acidic, with a pH 4.40, due to urban pollution and acid rain, and is not good for plant growth. Most of the artificial forests, natural forests, and arable land were found using land use and extant life surveys. Old trees were distributed in artificial forests, the oak clusters in natural forests, and the fields and darrinones were distributed in the arable areas. As the forest vegetation declined, the cedar forest was underway, and the cedar trees and red bean pear trees were cultivated due to their adaptability to the urban environment. There are 13 large of 180 sacks, one being 109 centimeters in diameter, the largest silvery tree, and 105 oak trees, provide food and shelter for animals. Six species of waterfowl that used the 22 kinds of forest wetlands, while four species of amphibians and two species of reptiles reside in the wetlands. Natural Monument No. 327, Mauryuk, Class II Endangered Wildlife, was also observed in the wetlands. Eight other species of surface dragonflies and three species of butterflies were observed. By systemizing the resources, members, and characteristics of the forest ecosystems in Suwon Yeongheung Park based on five criteria, the program for a hands-on natural education was presented with the aim of understanding the urban forest ecosystem in Suwon Yeongheung Park, having an affinity with the city, and recognizing its relationship with the community and society. However, further research is needed as there are limitations of research on programs characterized by different ages and classes.

• Journal of agricultural medicine and community health
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• v.34 no.1
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• pp.24-33
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• 2009

Objectives: In September 2008, an outbreak of diarrhea occurred among students attending Y school in Yeongcheon-si. Shigella sonnei was cultured from some of the rectal swabs. An epidemiological investigation was carried out to determine the source of the infection and the mode of transmission of the shigellosis outbreak. Methods: The index case lived in the D rehabilitation facility in Gyeongsan-si and an additional epidemiological investigation was carried out there. The cases could not be questioned due to their mental handicaps. The teachers were interviewed instead. A patient case was defined as a resident with diarrhea more than one time a day from September 18 to September 26, 2008 or a resident with confirmed Shigella sonnei at the Y school or the D rehabilitation facility. Results: The attack rate was 1.2% (8 persons) among 659 persons in the Y school and D rehabilitation facility. Five persons were microbiologically confirmed to have the infection and three persons were diagnosed on the basis of symptoms. Shigella sonnei was cultured from five of the 659 rectal swabs. However, 80 environmental specimens including drinking water, preserved foods, and cooking utensils were negative. All eight patients were Y school students and had been living in group boarding and lodging. Six of them lived in the D rehabilitation facility and two lived in the dormitory at the Y school. Five cases showed pulsed-field gel electrophoresis patterns that were identical for Shigella sonnei. Conclusions: The results of this study showed that the infection source of the shigellosis outbreak, in the two places, were identical. It is likely that the infections initially spread from a teacher or volunteer and then among the students.

• Journal of IKEEE
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• v.23 no.4
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• pp.1461-1464
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• 2019

In this paper, we propose the development of embedded board for integrated radiation exposure protection fireman's life-saving alarm capable of location tracking and radiation measurement. The proposed techniques consist of signal processing unit, communication unit, power unit, main control unit. Signal processing units apply shielding design, noise reduction technology and electromagnetic wave subtraction technology. The communication unit is designed to communicate using the wifi method. In the main control unit, power consumption is reduced to a minimum, and a high performance system is formed through small, high density and low heat generation. The proposed techniques are equipment operated by exposure to poor conditions, such as disaster and fire sites, so they are designed and manufactured for external appearance considering waterproof and thermal endurance. The proposed techniques were tested by an authorized testing agency to determine the effectiveness of embedded board. The waterproof grade has achieved the IP67 rating, which can maintain stable performance even when flooded with water at the disaster site due to the nature of the fireman's equipment. The operating temperature was measured in the range of -10℃ to 50℃ to cope with a wide range of environmental changes at the disaster site. The battery life was measured to be available 144 hours after a single charge to cope with emergency disasters such as a collapse accident. The maximum communication distance, including the PCB, was measured to operate at 54.2 meters, a range wider than the existing 50 meters, at a straight line with the command-and-control vehicle in the event of a disaster. Therefore, the effectiveness of embedded board for embedded board for integrated radiation exposure protection fireman's life-saving alarm has been demonstrated.

• Journal of the Korean earth science society
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• v.41 no.5
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• pp.469-477
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• 2020

Salinity is not only an important variable that determines the density of the ocean but also one of the main parameters representing the global water cycle. Ocean salinity observations have been mainly conducted using ships, Argo floats, and buoys. Since the first satellite salinity was launched in 2009, it is also possible to observe sea surface salinity in the global ocean using satellite salinity data. However, the satellite salinity data contain various errors, it is necessary to validate its accuracy before applying it as research data. In this study, the salinity accuracy between the Soil Moisture Active Passive (SMAP) satellite salinity data and the in-situ salinity data provided by the Ieodo ocean research station was evaluated, and the error characteristics were analyzed from April 2015 to August 2020. As a result, a total of 314 match-up points were produced, and the root mean square error (RMSE) and mean bias of salinity were 1.79 and 0.91 psu, respectively. Overall, the satellite salinity was overestimated compare to the in-situ salinity. Satellite salinity is dependent on various marine environmental factors such as season, sea surface temperature (SST), and wind speed. In summer, the difference between the satellite salinity and the in-situ salinity was less than 0.18 psu. This means that the accuracy of satellite salinity increases at high SST rather than at low SST. This accuracy was affected by the sensitivity of the sensor. Likewise, the error was reduced at wind speeds greater than 5 m s^-1. This study suggests that satellite-derived salinity data should be used in coastal areas for limited use by checking if they are suitable for specific research purposes.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.329-336
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• 2014

As an abiotic stress, chilling stress is one of the major factors limiting plant growth and increasing susceptibility to pathogens. Therefore, enhancing stress tolerance in plants is an important strategy for their survival under unfavorable environmental conditions. The objective of this study was to determine the effects of the exogenous application of salicylic acid (SA) or nitric oxide (NO) on chilling tolerance in pepper seedlings. Pepper (Capsicum annuum L. 'kidaemanbal') seedlings were grown under normal growing conditions ($20/25^{\circ}C$, 15 hours photoperiod, $145{\pm}5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, fluorescence lamps) for 23 days after transplanting. The solution (3 mL) of 1 mM SA and 0.3 mM NO with surfactant triton 0.1% were sprayed two times a week, respectively. Right after the completion of chemical application, seedlings were subjected to chilling condition at $4^{\circ}C$ for 6 hours under dark condition and then the seedlings were recovered at the normal growing conditions for 2 days. In order to assess plant tolerance against chilling stress, growth characteristics, chlorophyll fluorescence (Fv/Fm), and membrane permeability were determined after chilling stress imposition. Total phenolic concentration and antioxidant capacity were measured during the whole experimental period. Disease incidence for pepper bacterial spot and wilt was also analyzed. Pepper seedlings treated with SA or NO were maintained similar dry mass ratio, while the value in control increased caused by chilling stress suggesting relatively more water loss in control plants. Electrolyte leakage of pepper seedlings treated with SA or NO was lower than that of control 2 days after chilling treatment. Fv/Fm rapidly decreased after chilling stress in control while the value of SA or NO was maintained about 0.8. SA increased higher total phenolic concentration and antioxidant capacity than NO and control during chemical treatment. In addition, increase in total phenolic concentration was observed after chilling stress in control and NO treatment. SA had an effect on the reduction of bacterial wilt in pepper seedlings. The results from this study revealed that pre-treatment with SA or NO using foliar spray was effective in chilling tolerance and the reduction of disease incidence in pepper seedlings.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.1
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• pp.1-17
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• 1982

The stream morphological characteristics of a river basin has a close correlation with the hydrological and hydraulic characteristics of the basin. In this study the correlations of flow duration and Hydraulic geometry with the stream morphological characteristics as well as the correlation between flow duration and hydraulic geometry were analyzed bases on the data for the Geum River basin. The purpose of this study was to provide the necessary informations for water utilization projects at ungauged locations along the river course. First of all, the stream morphological characteristics was analyzed based on the Horton's three laws on the morphology of a stream that is, the law of stream number, the law of average stream length and the law of average stream slope. As is the case for majority of the rivers it was found that the Geum River basin was well developed according to the Horton's laws. High correlations were also found between the basin characteristics and the channel characteristics. The flow duration curves obtained with the daily stream flow data of 10~90% frequency of occurences at the five stage gauging stations in the Geum River could, in general, be expressed as an exponential functional relationship. The concept of proportional stream ordering system was employed to describe continuously the longitudinal variation of the stream morphological characteristics, and the mathematical model was formulated for the discharge-frequency-proportional stream order relationship. With the morphological characteristics as a common parameter the relationships with flow duration, drainage area were established in mathematical expressions, respectively.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.162-169
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• 2008

To determine suitable composition of nutrient solution according to soil textures in fertigation culture of cucumber using three strengths (S) of Yamasaki cucumber recipe, chemical changes of soil, growth characteristics and yield of cucumber were investigated. Electric conductivity of drainage solution was risen in all treatments, pH of loam soil was generally optimum level and that of sandy soil was high level. Photosynthetic rate in loam soil supplied the 1/2 S and transpiration rate in sandy soil supplied the 1.0 S were most low. Diffusive resistance in sandy soil supplied the 1.0 S was high. Chlorophyll contents was higher concentrations by the kinds of soil. Amount of drainage solution in sandy loam soil supplied the 1/2 S and loam soil supplied the 1.0 S were most much and little, respectively. Water absorption rate was the opposition to amount of drainage solution. Nutrient contents in soil except calcium were most high in the 1.0 S by the kinds of soil. Nutrient contents in leaves, nitrogen in sandy soil supplied 1.0 S, phosphorus in loam soil supplied 1/2 S, potassium in two soil supplied 1.0 S, calcium in loam supplied 1/2 S and sandy loam soil supplied 1.0 S, magnesium in loam soil supplied the 1/2 S was high. The growth and yield of fruit were more in loam than in sandy loam soil. Therefore, the suitable compositions of macro-nutrients for fertigation culture of cucumber were determined in loam and sandy loam soils as follows: In loam soil, they were $NO_3$-N 12.3, $NH_4$-N 1.0, P 3.0, K 5.9, Ca 5.7, Mg $3.5\;me{\cdot}L^{-1}$, whereas in sandy loam soil $NO_3$-N 11.7, $NH_4$-N 1.0, P 3.0, K 5.9, Ca 4.9, Mg $3.2\;me\;L^{-1}$.