• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.1
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• pp.38-48
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• 2004

Tropospheric ozone data in Korea for 1998-2002 were analyzed to assess the impact on vegetation. SUM06(sum of hourly concentrations at or above 0.06 ppm) and AOT40(accumulated exposure over a threshold of 40 ppb), widely used as ozone indices in the U.S. and Europe, were calculated based on hourly ozone concentration in 612 areas during 1998-2002 in Korea. SUM06 of the highest 30 areas were 5-12 ppm/hr which were almost the same levels of the U.S. average, and a crop loss of 5% would be expected. Ozone pollution in Seoul during 1998-2002 had decreased compared to that for 1990-97 except in the Northern area; however, ozone pollution in Kyunggi during 1998-2002 had been increased twice compare to the previous 5 years. Korea was divided into four regions: Seoul Metropolitan area, Jungbu, Honam, and Youngnam. Ozone pollution in the Seoul Metropolitan area was much higher during 1998-2000 than the other areas, but ozone pollution during 2001-2002 was almost the same in all four regions. Chunnam-Kwangyang na Kyungbuk-Gumi, famous industrial complexes in southern Korea, were significant ozone pollution areas. However, other industrial complexes, such as Incheon, Ulsan, and Kyunggi-Sihwa, were not polluted compared to their neighbors. Comparing all ozone indices, SUM06(yr), SUM06(3mon), AOT40(yr), AOT40(3mon), number of hours exceeding 100 ppb, 95 percentile, 99 percentile, and maximum concentration, it was determined reasonable to use SUM06(3mon), AOT40(3mon) and number of hours exceeding 100 ppb for evaluation of the chronic impact of ozone on vegetation.

• Journal of dental hygiene science
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• v.16 no.2
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• pp.111-117
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• 2016

The purpose of this study was to assess the relationship that adolescent stress perception level has with dietary habits and oral health behaviors in high school students. A survey of high school students in some areas of the Jeollabuk-do province of South Korea was conducted. Five hundred fourteen survey responses were used in the final analysis. As a result of the questionnaire survey, the following conclusions were obtained. The highest stress type was indicated to be academic stress (mean${\pm}$standard deviation [SD], $3.09{\pm}0.89$). The next was shown to be home (family) stress (mean${\pm}$SD, $2.85{\pm}0.84$). The possibility of using a dental clinic was indicated to be less in girls than boys (p<0.001). Regarding subjective oral health behavior, the possibility of visiting a dental clinic was low in those who thought that their own oral health condition was not good or moderate (p<0.05). Also, it was shown that the higher stress led to the higher possibility of visiting a dental clinic (p<0.01). Students with higher grades had a in the upper ranks were indicated to have high possibility of having a regular meal (p<0.01). Higher stress led to the significantly higher possibility of eating cariogenic food (p<0.01). Students with median grades had a high possibility of eating cariogenic food (p<0.01), while students with higher grades had a low possibility of eating cariogenic food (p<0.05). These resultss show that stress perception level influences dietary habits and oral health behaviors. Thus, there is a need to develop a program in high scholls to promote the physical and mental health of students to relieve stress. Substantial and systematic oral health education is thought to be likely needed to develop desirable dietary habits.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.243-254
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• 2019

With the recent accelerated policy-making and interests in new renewable energy, plans to develop and supply the new renewable energy have been devised across multiple regions in Korea. Solar energy, in particular, is being applied to small-scale power supply in provincial areas, as solar cells are used to convert solar energy into electric energy to produce electric power. Nonetheless, in the case of solar power plants, the need for a large stretch of land and considerable sum of financial support implies that the planning step should take into consideration the most suitable meteorological and geographical factors. In this study, the proxy variables of meteorological and geographical factors associated with solar energy were considered in analyzing the vulnerable areas regarding the photovoltaic power generation facility across the nation. GIS was used in the spatial analysis to develop a map for assessing the optimal location for photovoltaic power generation facility. The final vulnerability map developed in this study did not reveal any areas that exhibit vulnerability level 5 (very high) or 1 (very low). Jeollanam-do showed the largest value of vulnerability level 4 (high), while a large value of vulnerability level 3 (moderate) was shown by several administrative districts including Gwangju metropolitan city, Jeollabuk-do, Chungcheongbuk-do, and Gangwon-do. A value of vulnerability level 2 (low) was shown by the metropolitan cities including Daegu, Ulsan, and Incheon. When the 30 currently operating solar power plants were compared and reviewed, most were found to be in an area of vulnerability level 2 or 3, indicating that the locations were relatively suitable for solar energy. However, the limited data quantity for solar power plants, which is the limitation of this study, prevents the accuracy of the findings to be clearly established. Nevertheless, the significance of this study lies in that an attempt has been made to assess the vulnerability map for photovoltaic power generation facility targeting various regions across the nation, through the use of the GIS-based spatial analysis technique that takes into account the diverse meteorological and geographical factors. Furthermore, by presenting the data obtained for all regions across the nation, the findings of this study are likely to prove useful as the basic data in fields related to the photovoltaic power generation.

• (The)Study of the Eastern Classic
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• no.72
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• pp.157-183
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• 2018

The purpose of this study was to investigate the existence aspects of the Hyangri class in Imsilhyeon, Jeolla Province in the latter half of Joseon based on Woonsuyeonbangseonsaengan, which provides lists of Hyangris in Imsilhyeon from the fourth year(1724) of King Gyeongjong's reign to the early 20th century. It contained the names of total 704 Hyangris, who included 119 Kims, 103 Eoms, 103 Jins, 87 Parks, 86 Muns, 66 Lees, 31 Baeks, 27 Hwangs, and 17 Taes. In addition, there were 12 more family names that produced fewer than ten Hyangris. Based on the share of representative family names among the Hyangris of the area, it is estimated that the dominant family names were Kim, Eom, Jin, Park, Mun, and Lee. Another interesting aspect is that the Jeon and Yang families produced no Hyangris in the 19th century, whereas the Hwang family produced 5% of Hyangris in the century with the Jin family accounting for 10% or more. These findings show that little changes were consistent within the community of Hyangris despite the fact that a couple of families were dominant. The family clans of the family names were checked in Nosogyean, which records that they were the Kim family of Gyeongju, Eom family of Yeongwol, Jin family of Namwon, Park family of Hamyang, Mun family of Nampyeong, and Lee family of Gyeongju. The study then examined the family names of 76 Hojangs that were recorded to hold the Hojang title in Woonsuyeonbangseonsaengan to see whether the family names that produced higher-level Hyangris were the same as the ones above. There was an overall agreement between the family names that produced a lot of Hojangs and those that produced the most Hyangris, but there were differences according to the periods. Six family names produced Hojangs in similar percentage in the 18th century, and only three family names, which were the Jin family of Namwon(13), Mun family of Nampyeong(9), and Eom family of Yeongwol(6), produced more than ten Hojangs in the 19th century. Other noteworthy changes in the 19th century include the rapidly rising frequency of Hojangs serving the term twice or more compared with the 18th century and the concentration of Hojangs on certain family names. These findings indicate that six family names coexisted in the active production of Hyangris in the community of Hyangris in Imsilhyeon in the latter half of Joseon, that there were changes to the family names of higher-level Hyangris internally according to the periods, and that a shift happened toward the leadership of certain family names in the society of Hyangris.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.312-317
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• 2014

This study was conducted to obtain basis information for effective weed control by the fact-finding survey of herbicides use at farmer's level and distribution of herbicide resistant weeds in paddy field of Jeonbuk province, Korea. The distributions of major paddy field weeds and frequently used herbicide according to the survey were as follows. The dominant weeds in rice paddy field were Echinochloa crus-galli, Eleocharis kuroguwai, Scirpus juncoides, Monochoria vaginalis, etc.. Preferred herbicides widely used by farmers were ranked in the following order, early and middle treatment (48.0%), treatment before transplanting (36.7%) and foliar treatment (15.3%). The occurrence of herbicide-resistant weeds according to collected paddy soils was as follows. The occurring area of herbicide-resistant weeds was 24,413 ha, approximately 18.4% of rice cultivation area. Herbicide-resistant weeds were occurred in four species. The order of occurrence were Scirpus juncoides (39.0%) > Monochoria vaginalis (27.8%) > Echinochloa crus-galli (16.6%) and Cyperus difformis (16.6%). This information could be useful for estimation of future herbicide-resistant weed and establishment of herbicide-resistant weed control methods in Jeonbuk province, Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.109-114
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• 2010

This experiment was carried out to know adaptability and forage production and quality of sorghum and sorghum ${\times}$ sudangrass and sudangrass hybrids at paddy field from 2007 to 2008 at Chonnam province. Among growth characters of six Hybrids, 'SX17' hybrid was somewhat strong for waterlogging, and higher sugar content and very good at the 2nd regrowth and disease resistance. Fresh yield of 'SX17' hybrid was the highest as 89,192kg per ha among 6 Sorghum and Sorghum ${\times}$ Sudangrass and Sudangrass hybrids. The dry matter yield of 'SX17' hybrid was also the highest as 21,038 kg per ha. The result of this study showed that 'SX17' hybrid had good growth characters and forage productivity and crude protein (CP) and in vitro dry matter digestibility (IVDMD).

• Korean journal of applied entomology
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• v.4
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• pp.33-38
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• 1965

1. This survey was conducted to make a basis for the cause of severe epidemic and disease control to the losses due to bacterial leaf blight of rice in Chun-Nam rice paddy field areas in the first part of October in 1965. The severe epidemic areas were included Taijun-Myun, Tamyang-Eup, riverside in Youngsanpo and seaside in the suburbs of Mokpo. 2. A drought in the period of rice transplanting and flooding due to a heavy rain in July were resulted reasonable weather conditions that the disease occurred more early and severe epidemic. 3. In Tamyang area, frist outbreak of the disease was on the middle part of July in the paddy flooded after heavy rainfall of the first fart of July. It is recognized to farmers that the disease is known as a now serious one. 4. The more date of transplanting is followed, the more serious damage is happened and especially, in the paddy field flooded, too. 5. Flooded areas showed more serious epidemic. 6. Varietal difference to the disease was surely noticed, and Kumnampoong and Chunbonwuk were susceptible, whereas Norin 6 was resistant. 7. Damage was occurred more in plant paddy area than tile slopping paddy area. 8. Fallow paddy field was more serious than the field using double cropping a year. 9. Moist and semimoist paddy field were more serious damage, while light damage in dry paddy field. 10. Near part of flood gate for drainage of submerge paddy was more serious damage than inside part of the field. 11. Soft type is often seen in the mode of the disease occurrences. 12. The most farmers insisted that dropping water is caused to promote disease dissemination when disease occurred.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.318-321
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• 2013

National Academy of Agricultural Science and eight province Agricultural Research & Extension Services investigated the occurring area of herbicide resistant weeds in paddy field of Korea. In order to estimate the occurring areas of herbicide resistant weeds, we collected paddy soils randomly from 3,200 sites in 2011 and 2012, and treated 30 kg $ha^{-1}$ of pyrazosulfuron-ethyl+pyriminobac-methyl GR to the paddy soil. 176,870 ha, approximately 22.1% of cultivated area excluding organic and eco-friendly cultivated area, was estimated to be infested by SUherbicide resistant paddy field weeds. Several species of resistant weeds were occurred at Jeonranam-do with 44.3%, followed by 30.5% at Chungchungnam-do, 27.8% at Chungchungbuk-do, and 24.5% at Jeonrabuk-do, respectively. Monochoria vaginalis showed the highest distribution with 57,018 ha, 32.2% followed by Scirpus juncoides, and Lindernia procumbens, respectively.

• Weed & Turfgrass Science
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• v.6 no.2
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• pp.130-135
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• 2017

In the current study, we surveyed the status of graveyard lawn maintenance in Korea. The lawn maintenance information was obtained from the vicarious companies registered on the internet portal site and the Forestry Federation of Korea, and the questionnaire investigation from Primary Agricultural Cooperatives (Nonghyup). In all provinces surveyed, individual graves were maintained on a $66m^2$ (20 Pyeong) basis. The vicarious maintenance of graveyard lawn was carried out 1~5 times a year, and the maintenance cost increased as the number of times increased. Mowing the grass around a grave (Beolcho) was mainly done before the Korean Thanksgiving Day (Chuseok). The number of Beolcho was steadily increased from 2013 to 2015, and the price was getting higher and higher. Gyeonggi province had the highest cost, and Jeolla had the lowest cost. Regardless of the year, the number of orders received were higher in Gyeongnam > Gyeongbuk > Jeonnam province in order. Most of the reason for requested Beolcho was because the client lives in the area far from the graveyard. The direction of the cemetery was very varied. According to the survey, the all grass were zoysiagrass (Zoysia japonica), and grass coverage rate of the graves was 35.4~71.9%. Through questionnaire investigation, the reason why the density of grass was lowered was because the periodic management of weeds and fallen leaves was insufficient. Further research on the maintenance of graveyard in the future will be necessary.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.5
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• pp.150-159
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• 2011

The need of securing the stability and extending service lives by efficient maintenance of deteriorated tunnels for several decades has been increased. The stability and the usability of conventional tunnels can be decreased by change of physical properties of the surrounding ground, geometrical properties of the tunnel, an underground water level, environmental conditions, oxidation of lining and the breakdown of constituent materials. In respect of a long-term view, it is need to check all sorts of degradation, the degree of damage and durability to improve the serviceability and to come up with measures to maintain effectively. This paper is about study to analyze the stability of conventional tunnels(American Steel Support Method. ASSM). Three tunnels are chosen in those built in the 1930s and 1960s and the locations of tunnels are selected variously(ChungCheong, GyungBuk, GangWon, Jeolla, etc.) to secure reliability of this study. The state of repair and reinforcement of linings, cracks, and thickness and strength of lining of conventional tunnels in service are researched, compared and analyzed. The crack gauge, the GPR, the schmitt hammer was used for the crack investigation, cavitation, the strength respectively. By using these, the comparative analysis for conventional tunnels was conducted. As a result, there are more cracks in tunnels built in the 1930s than those of tunnels built in the 1960s, and lining strength of the 1930s is higher than those of the 1960s. The thickness of lining in tunnels built in the 1960s is higher than those in tunnels built in the 1930s. In proportion to thickness, cavitation occurred more frequently in tunnels built in the 1960s compared to those in tunnels built in the 1930s.