• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.71-81
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• 2020

In Korea, more than 70% of the ammonia(NH₃) released into the atmosphere is known to originate from livestock manure. The total emission (kg year^-1) is calculated by multiplying the emission factor (kg head^-1 yr^-1) and the activity data (head). To improve the accuracy and reliability of the NH₃ emission estimation process, an accurate account of livestock manure production, calculation of NH₃ conversion and generation during the composting and liquefaction of manure, estimation of NH₃ generation in the storage and transportation of manure and compost, and a comparative study of NH₃ emission during the soil spreading process must be performed. Compared to the US and EU-28, in particular, the domestic emission factor is relatively even and the spatial/temporal scale is not broken down sufficiently to reflect the domestic situation. As a way to improve the accuracy and expertise of estimating NH₃ emission factors, a 'dynamic chamber-capture system' can be utilized, which allows complex considerations of compost, liquid manure, soil, and climate characteristics. By reviewing and comparing the data related to domestic and foreign NH₃ emission, we identified shortcomings in the current domestic system and the directions to be taken and suggested a chamber system that could estimate NH₃ emission flux. It is also necessary to establish a methodology for mesocosm systems in the field, in addition to indoor chamber systems, to be linked with practical policies, such as the calculation of new emission factors for missing sources.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.657-665
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• 2013

A large patch disease caused by Rhizoctonia solani AG2-2 (IV) is a serious problem in Korean lawngrass (Zoysia japonica) sites including golf courses and sports fields in Korea. Antagonistic microorganisms against R. solani AG2-2 (IV) were isolated from various forest and crop soil sources in Southern Korea. Among the 61 isolates, I-009, FRIN-001-1, and YPIN-022 strains showing dramatic inhibition of the mycelial growth of R. solani AG2-2 (IV) in the pairing culture were selected as the most potential antagonistic microorganisms for this study. Based on the 16s RNA sequence comparison, I-009 and FRIN-001-1 isolates were identified as Bacillus spp., while YPIN-022 isolate belongs to the genus Pseudomonas. The greater inhibition (clear) zone between two edges of the selected and pathogenic microbes ranged from 11 to 15 mm in three selections, but the others averaged to 7 mm out of 30 mm distance. In another antifungal test using culture filtrate, those three isolates represented a range of 51.7 to 63.5% suppression potential. The selected isolates also inhibited significantly the stem-segment colonization by R. solani AG2-2 (IV) in vivo test by 28.1%, 43.0%, and 23.7% when inoculated with I-009, FRIN-001-1, and YPIN-022, respectively. The highest antagonistic activity for the large patch disease was demonstrated by the isolate FRIN-001-1, which will be useful for developing a bio-pesticide against Rhizoctonia.

• Journal of the Korean association of regional geographers
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• v.17 no.4
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• pp.416-431
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• 2011

Hiking trails in Mt Jiri, and Mt Halla, National Park have been examined in terms of their degrading factors. The trails are deteriorated by natural erosion processes as well as human trampling. Trail deterioration is classified into tread lowering, sidewall retreat, path widening and divergence based upon a place where erosional processes occur. Tread lowering and sidewall retreat is generally produced by natural erosion factors, whereas path widening and divergence is generated by human trampling. Rainwash is the most contributing process to tread lowering. By contrast, several processes such as rainwash, needle ice action, deflation, tree falling and animal activity play a major role in sidewall retreat according to physical conditions of a hiking trail. Path widening and divergence could be classified by a factor producing human trampling. There are lots of cases related to rainwash such as the tree root, gravel, and bedrock, exposed by a surface flow lowering a tread and the riser produced by tread scouring. A puddle of rainwater on a flat tread and a fallen tree of Abies koreana in a forest region are also major factors to cause path widening and divergence. A paved tread with stones encourages a hiker to walk out of a trail. Taking a shortcut also results in path widening and divergence without a factor giving a hiker inconvenience on a trail.

• Korean Journal of Environmental Biology
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• v.17 no.2
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• pp.191-198
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• 1999

Enzyme-aided bleaching of softwood and hardwood kraft pulps by a xylanase preparation from an alkalophilic fungus Cephalospotium sp. RYM-202 was studied. Maximal solubilization of Pulp xylan was obtained at 5$0^{\circ}C$ in both kraft pulps. The optimum pH of the enzyme for the hydrolysis of pulp xylan was 8.0 and more than 90% of the maximal activity was detected at 9.0. The positive effects of xylanase pretreatment on bleachability of softwood and hardwood kraft pulps were observed. The kappa number of softwood and hardwood kraft pulps was decreased by 3.7 and 2.0 units, respectively. The pulp fibre integrity was not significantly affected by xylanase pretreatment when the physical properties of handsheets made from xylanase-treated pulps were compared with those of handsheets from untreated pulps. These results indicate that the alkaline xylanase of Cephalospotium sp. RYM-202 is well suitable for application in enzymatic prebleaching of softwood and hardwood kraft pulps under the alkaline conditions.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.5
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• pp.53-63
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• 2009

This study aims at presenting a plan to build an open space network system in the city of Daejeon, assuming that parks and the green space system as a broad concept are to make a network by connecting open spaces such as parks, green spaces, squares, pedestrian roads, historical spots, etc. In the case of old downtown in Daejeon, this study examined the possibility of applying an open space network in the city of Daejeon and categorize them according to the findings from examining the case area, which enables to make a plan for building an open space network system in Daejeon. As a result, public offices and business buildings as an active open space have public open spaces in front of buildings and these front public open spaces are connected to pedestrian roads(gray open space). Since these pedestrian roads are consequently connected to large parks and rivers(green or blue open space), this overall spatial sequence can form an open space system. In addition, parks and green spaces, which have been fundamental elements so far, exist in relatively small and scattered areas at the center of the city. Hence, more parks and green space are needed to improve a park and green space system. However, it is very difficult to create new parks and green spaces in downtown, especially in old downtown areas. Therefore making an open space network system which spreads out over the whole city will form a healthy open space network in the downtown area.

• Safety and Health at Work
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• v.11 no.2
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• pp.178-186
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• 2020

Background: Cognitive impairment is a public health burden. Our objective was to investigate associations between work hours and cognitive function. Methods: Multi-Ethnic Study of Atherosclerosis (MESA) participants (n = 2,497; 50.7% men; age range 44-84 years) reported hours per week worked in all jobs in Exams 1 (2000-2002), 2 (2002-2004), 3 (2004-2005), and 5 (2010-2011). Cognitive function was assessed (Exam 5) using the Cognitive Abilities Screening Instrument (version 2), a measure of global cognitive functioning; the Digit Symbol Coding, a measure of processing speed; and the Digit Span test, a measure of attention and working memory. We used a prospective approach and linear regression to assess associations for every 10 hours of work. Results: Among all participants, associations of hours worked with cognitive function of any type were not statistically significant. In occupation-stratified analyses (interaction p = 0.051), longer work hours were associated with poorer global cognitive function among Sales/Office and blue-collar workers, after adjustment for age, sex, physical activity, body mass index, race/ethnicity, educational level, annual income, history of heart attack, diabetes, apolipoprotein E-epsilon 4 allele (ApoE4) status, birth-place, number of years in the United States, language spoken at MESA Exam 1, and work hours at Exam 5 (β = -0.55, 95% CI = -0.99, -0.09) and (β = -0.80, -1.51, -0.09), respectively. In occupation-stratified analyses (interaction p = 0.040), we also observed an inverse association with processing speed among blue-collar workers (adjusted β = -0.80, -1.52, -0.07). Sex, race/ethnicity, and ApoE4 did not significantly modify associations between work hours and cognitive function. Conclusion: Weak inverse associations were observed between work hours and cognitive function among Sales/Office and blue-collar workers.

• Journal of Ginseng Research
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• v.20 no.4
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• pp.472-500
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• 1996

Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

• Korean Journal of Environment and Ecology
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• v.16 no.3
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• pp.261-270
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• 2002

The purpose of this study is to survey and analyze of the visitor's cognition of admission fee collection system in National Park. To accomplish the purposes, a questionnaire survey was employed in Songnisan National Park. The contents of questionnaire consist of the socioeconomic characteristics and the types of visiting, the activity, the cognition of admission fee collection system.339 samples of total 345 respondents were used for final analysis. As a result of the analysis, the socioeconomic characteristics and the types of visiting, the visiting purpose were showed similar trends with results from other National Park visitors survey. Most of respondents didn't recognize the raise of admission fee and how to use the admission fee. And they recognized that it is too expensive. Most of respondents recognized the joint collection of admission fee but they were strong against it. About the range of cultural assets in National Park, the cognition of 'Only Buddhism's assets in temple' was almost equal with the cognition of 'It includes not only cultural assets of inside and outside temple but also thick forest in National Park'. But most of respondents were strong against the collection of admission fee of cultural assets.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.174-183
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• 2015

We have conducted a verification test of correlation between bird community indices and bird sound recording results in order to use the equipment which deals with the automatic sound collecting system, the song meter. The study areas include four sites which are Gombaeryoung and Zochimryoung in Jeombongsan Mountain and Jookryoung and Gochiryoung in Sobaeksan National Park. We collected the bird sound data five times using a sound recorder and field survey results in the same place of the study site. As a result of the sound recording from the field survey, the species recorded by three researchers of sound analyst include common resident species or species which have a relatively conspicuous call and song. On the contrary, the species recorded by only one researcher are a relatively rare or inconspicuous species or was familiar with the personal experiences of each researcher. The number of species recorded by only one researcher totaled fourteen species (36.8 %), and that of two researchers totaled twelve species (31.6 %), and that of three researchers totaled twelve species (31.6 %). The correlations of the number of species among three researchers was not significant in some results, but the sum or maximum count of the number of species was useful to estimate a significant correlation between the result of researchers and the indices of field surveys. As a result of correlation analysis by using sound recordings, the maximum number of species among the three researchers significantly correlated with the number of species, the species diversity index and the species abundance index in the field survey at the same site, however it did not correlate with the number of individuals and species evenness index. As a result of sound analysis collected from the stationary sound recording system; song meter, the number of frequencies in bird songs and calls correlated with the number of species in the field survey at the same site. The number of calls and songs decreased as time went by. Finally, we could test the active time range and change the activity strength by using a sound recording system. In particular, that sound recording system is able to collect data in same time and site, so it is expected so that the equipment not only replenish a shortage of researchers and survey periods in field research in a short term monitoring survey, but also be able to acquire statistical objectivity.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.799-813
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• 2011

Increasing mountain biking (MTB) in forest recreation areas is changing the behavioral patterns in the areas where hiking has been a dominant activity, and it may cause ecological and social impacts to the areas. This study examined hikers' perceived conflicts by MTB including the relationship between socio-demographic and visiting characteristics and perceived conflict. On-site survey was conducted in Mudeungsan Provincial Park (MPP), Korea, during September, 2010. Out of 388 hikers participated in the survey, 374 responses were used for data analysis. 30.2% of the respondents encountered or saw MTB (avg.: 1.7 times) in MPP. Overall, 77.1% of respondents thought MTB in MPP was a problem. 73.5%~83.2% of respondents perceived conflict by four major MTB behaviors (e.g., too fast running MTB in trails; MTB bikes occupying trails; MTB bikes passing by hikers too closely; MTB bikers doing unpleasant behaviors to hikers). Based on the type of conflict, 48.5~62.4% of respondents fell in the type of "social values conflict (SVC)", 11.1~32.4%, "interpersonal conflict (IC)", and 16.8~26.6%, "no conflict (NC)", respectively. Types of conflicts were related with sociodemographic (e.g., gender, age, education) and visiting characteristics (e.g., number of visits, experience of encountering MTB). Such relationships were nonexistent in most cases when the "experience of encountering MTB" was controlled.