• Journal of Korean Ophthalmic Optics Society
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• v.16 no.4
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• pp.391-401
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• 2011

Purpose: In the present study, the actual management state of trial contact lenses and lens care products in local optical shops was surveyed and analyzed to reduce the risk of lens complication possibly induced by neglecting lens care. Methods: The feeling of contact lens wearers during the wear of trial contact lenses was surveyed. Futhermore, the actual management state of trial contact lenses such as cosmetic lens and RGP lens and lens care products was also investigated by surveying opticians who trade contact lenses in local optical shops. Results: It was found that consumers trusted the sanitary conditions of the lens since trial cosmetic contact lens and RGP lens were cleaned before and after trails by over 98% of opticians in local optical shops. For trial cosmetic lens, cleaning with normal saline, multipurpose solution for soft lens and combination of saline and multipurpose solution were 38.5%, 40.5% and 21%, respectively, before trials. After trials, cosmetic lenses were cleaned with normal saline, multipurpose solution for soft lens and a combination of saline and multipurpose solution were 13%, 75%, and 12%, respectively. On the other hand, cleaning with normal saline, multipurpose solution for RGP lens and combination of saline and multipurpose solution were 28.5%, 38.5% and 33%, respectively, before trying trial RGP lens. After trials, RGP lenses were cleaned with normal saline, multipurpose solution for RGP lens and a combination of saline and multipurpose solution were 2.5%, 70%, and 27.5%, respectively, indicating that relatively many opticians followed the lens cleaning regimen. In local optical shops, the cleaning trial cosmetic lens was mainly conducted at every 10 days or a month and the washing cycle of cosmetic lens case was in a month or 2~3 months. The cleaning interval of trial RGP lens was primarily in a month or 2~3 months. For those lens cases, more than 75% of opticians washed them with a surfactant and then rinsed with cold water. The storing periods of lens care products were primarily in a week for saline and in a month and 2~3 months indicating that storing period of lens care products was relatively well-kept in local optical shops. Conclusions: It is thought that the concern about any microbial infection is not that high since trial contact lenses and lens care products were generally well-managed by opticians in local optical shops from the results above. However, better public eye health and better public confidence in opticians may be possible if further strengthen in avoidance of lens cleaning with saline, keep of cleaning cycles within 2 weeks and rinsing of lens cases with hot water happens.

• Journal of Korea Water Resources Association
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• v.44 no.10
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• pp.797-807
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• 2011

Phenomenon of vegetation recruitment on the sand bar is drastically rising in the streams and rivers in Korea. In the 1960s prior to industrialization and urbanization, most of the streams were consisted of sands and gravels, what we call, 'White River'. Owing to dam construction, stream maintenance, etc. carried out since the '70s, the characteristic of flow duration and sediment transport have been disturbed resulting in the abundance of vegetation in the waterfront, that is, 'Green River' is under progress. This study purposed to identify the correlation among water level, water temperature, rainfall, soil moisture and soil texture out of the factors which give an effect on the vegetation recruitment on the sand bar of unregulated stream. To this purpose, this study selected the downstream of Naeseong Stream, one of sand rivers in Korea, as the river section for test and conducted the monitoring and analysis for 289 days. In addition, this study analyzed the aerial photos taken from 1970 to 2009 in order to identify the aged change in vegetation from the past to the present. The range of the tested river section was 361 m in transverse length and about 2 km in longitudinal length. According to the survey analysis, the tested river section in Naeseong Stream was a gaining river showing the higher underground-water level by 20~30 m compared to Stream water level. The difference in the underground water temperature was less than $5^{\circ}C$ by day and season and the Stream temperature did not fall to $10^{\circ}C$ and less from May when the vegetation germination begins in earnest. The impact factor on soil moisture was the underground water level in the lower layer and the rainfall in the upper layer and it was found that all the upper and lower layer were influenced by soil particle size. The soil from surface to 1 m-underground out of 6 soil moisture-measured points was sand with the $D_{50}$ size of 0.07~1.37 mm and it's assumed that the capillary height possible in the particle size would reach around 14~43 cm. On the other hand, according to the result of space analysis on the tested river section of unregulated stream for 40 years, it was found that the artificial disturbance and drought promoted the vegetation recruitment and the flooding resulted in the frequency extinction of vegetation communities. Even though the small and large scales of recruitment and extinction in vegetation have been repeated since 1970, the present vegetation area increased clearly compared to the past. It's found that the vegetation area is gradually increasing over time.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.3
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• pp.25-37
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• 2013

The purpose of this study is to draw reasonable management plans to reinforce essence of Ohyundan(五賢壇: Five sprit tablets), a sacred site and monument of Jeju, by investigating and analyzing current status and problems of cultural landscape elements(e.g. architectural structures, installation, letters carved on the rocks, actual vegetation, etc.) while grasping placeness contained in Ohyundan through consideration of its history and transition process of Ohyundan a future being and shrine of Gyulrim Seowon(橘林書院) in Jeju. Results derived from research are summarized as follows. Ohyundan is noted due to its placeness in that it was a place for Gyulrim Seowon, Jeju's one and only Saaek Seowon(賜額書 院) and it was a symbolic space of exile culture in Jeju. As it is inferred from Gyulrim Seowon, which is dangho(堂號: clan name) of Seowon, orchards surrounding all over places are a signature landscape element that shows placeness of the past Ohyundan. Joduseok(俎豆石: altar stone), representing a core installation of Ohyundan and ancestral tablet of five spirits, created a refined place by putting up common stones around altar and founding blocked stones to wall. This refinement and thrift served basic mind of Neo-Confucianism, and led to of Jeju's Jonyang mind(spend-thrift mind). In conclusion, a practice plan is a prerequisite to restore essence of Ohyundan by actively excluding installations not suitable for placeness or overly designed such as Jeju Hyangrodang(a center for the elderly) and numerous monument houses. On the other hand, together with Joduseok, as letters carved on the rocks such as 'Jeungjoo Byukrip(曾朱壁立)' and 'Gwangpoongdae(光風臺)' and Yoocheonseok serve as a signature landscape that well shows mind of five spirits and teaching of Neo-Confucianism, and also a trace from a confucian viewpoint deeply rooted in Jeju, they are judged as a cultural landscape corresponding to the essence of place in Ohyundan which requires proactive preservation and plans for public relations. Together with this, although many different old big trees such as Pinus densiflora , Pinus thunbergii, Quercus variabilis, Celtis sinenis, Zelkova serrata and Rhus succedanea are a landscape element that increases sacred Ohyundan and commemorative value, now required is thorough entity tree management by assigning serial number on them as many of them were dead or removed resulting from transition process of land use. Further, to reinforce quality of site location belonging to Gyulrim Seowon, a prerequsite is to review plans that create Gyulrim at reinstalled site of building and raw land.

• Journal of Korean Society of Forest Science
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• v.48 no.1
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• pp.51-58
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• 1980

Translocation of $^{14}C$-labelled photosynthate from needles to terminal buds of Pinus elliottii was studied to understand a pattern of mobilization of photosynthate to buds during the period of female strobilus initiation. Current-year shoots of 20-year-old trees were exposed in 1ate July and late August to $50{\mu}$ Ci of $^{14}CO_2$ for 90 minutes, and harvested 1 day and 7 days after the exposure to analyze distribution of $^{14}C$ in ethanol-soluble and ethanol-insoluble fractions. Over 85% of total radioactivity of bud tissue one day after the exposure and 55% total activity seven days after the exposure remained in the ethanol-soluble fraction. The amount of $^{14}C$ translocation into female-producing buds in late August was significantly less than into vegetative and male-producing buds both one day and seven days after the exposure. When the ethanol­soluble fraction was further fractionated into hexane-soluble, amino acid, sugar, and organic acid fractions, radioactivity in the female-producing buds in late August was about a third of that in male-producing buds in all the fractions. This indicated that the male-producing buds required in late August but not in late July mobilization of large amount of photosynthate for developing male strobilus primordia. Fema1e-producing buds, on the other hand, did not mobilize as much photosynthate as male-producing buds in late August when female strobilus primordia are believed to be initiated. It is suggested that initiation of the female strobilus primordia is associated with temporary reduction in the metabolic activity of the terminal buds in slash pine.

• Journal of the Korean Chemical Society
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• v.56 no.6
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• pp.751-758
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• 2012

In this study, we analyzed career paths and college life plans of department of chemistry education students in teacher's college examined by their roadmaps. We let students make their roadmaps and analyzed them using the PASW 18 program. There were significant differences on gender in their career paths, learning English, traveling and volunteer activity. Female students for passing the MEET(Medical Education Eligibility Test) or DEET(Dental Education Eligibility Test) were more interested in learning English and traveling than male students. In addition, female students were more interested in volunteer activity. And the lower year students, the more interested in medical paths, learning English, traveling, getting good grades, exchange student program and scholarship. On the other hand the higher year students, the more interested in group study or E-learning. Then significant differences were in learning English, traveling and getting good grades by students's career paths. Students who wish to pass the MEET or DEET were more interested in learning English and getting good grades. Those two factors were essential in passing the MEET or DEET. Students who did not specified their career paths had more traveling plans than other students for setting their directions of careers. These results show that freshman and female students don't recognize the identity of teacher's college correctly. Because of reduction in the number of teacher recruitment according to decrease of students by birth rate drop, students in teacher's college are expected to continue like this trend that students look for other paths. Therefore, it is required career counseling and guidance for students who give priority practical path choices and college life plans over original characteristics of teacher's college. And it should be reconsidered the direction of chemistry education prepared the identity of teacher's college reflected in this actuality.

• Journal of dental hygiene science
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• v.6 no.3
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• pp.159-162
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• 2006

This study examined the relationship between the quantity of Streptococcus mutans and Lactobacillus spp. related to dental caries and the degree of acidity in saliva. A total of 240 saliva samples were taken from 80 subjects at the faculty of dentistry in Skopje, Macedonia. The saliva samples were taken by stimulating saliva production stimulation with paraffin chewing. However, no stimulation was applied when obtaining the samples used for measuring the pH. The data showed that in the caries group, S. mutans in 1 ml of saliva formed colonies with confluent growth (CFU > $10^6$ and $10^4-10^5$) in 100% of samples, whereas the Lactobacillus spp. formed colonies with confluent growth in 78.3%. In contrast, no colonies with confluent growth (CFU > $10^6$ and $10^5$) were found in the control group (with healthy intact teeth). In the caries group, the pH of the saliva was slightly acidic (pH = 5.90 - 6.50) and the buffering capacity was very low (below 0.7 ml of saliva per min). On the other hand, the pH of the saliva in the control group was neutral (pH 7.01 - 7.7) and the buffering capacity was high (over 1 ml of saliva per min). The increased number of S. mutans and Lactobacillus spp. in 1 ml of saliva (above $10^5$ CFU or more) from the CRT (Caries Risk Test, Vivadent, Liechtenstein) bacteria test can indicate an increased caries risk as well as slightly higher acidity of the saliva. Overall, these results reveal that the caries risk can be predicted by simply measuring the pH and buffering capacity of saliva, and can be used to monitor the effect of dental hygiene practices with the aim of preventing dental caries.

• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.426-435
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• 2010

The present study attempts to compare the soil chemical characteristics and biological activities (i.e. microbial biomass and soil enzyme activities), and litter decomposition rate of Arundinella hirta and Miscanthus sinensis var. purpurascens) collected from serpentine and non-serpentine sites by litter bag techniques at serpentine and non-serpentine field experiment sites over a 9-month period. The serpentine soil showed higher pH and soil alkaliphosphatase activity, and lower soil dehydrogenase and urease activities than the non-serpentine soil. Microbial biomass-N at the serpentine soil was larger than the non-serpentine soil, although the microbial biomass-C and microbial biomass-N represented no significant difference between serpentine and non-serpentine soil. These results suggest that the larger microbial biomass-N caused the lower C/N in serpentine soil. At the end of the experiment, the litter samples of A. hirta and M. sinensis collected from serpentine soil revealed a 39.8% and 38.5% mass loss, and the litter sample from non-serpentine soil also showed a 41.1% and 41.7% mass loss at the serpentine site. On the other hand, at the non-serpentine site, 42.2%, 37.4%, and 46.8%, 44.8% were respectively shown. These results demonstrate that the litter decomposition rate is more intensely affected by the heavy metal content of leaf litter than soil contamination. Moreover, the litter collected from the serpentine soil had a lower C/N, whereas the litter decomposition rate was slower than the litter from the non-serpentine soil, because the heavy metal inhibition activities on the litter decomposition process were more conspicuous than the effect of litter qualities such as C/N ratio or lignin/N. The nutrient element content in the decomposing litter was gradually leached out, but heavy metals and Mg were accumulated in the decaying litter. This phenomenon was conspicuous at the serpentine site during the process of decomposition.

• Korean Journal of Environment and Ecology
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• v.28 no.1
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• pp.90-98
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• 2014

This study was carried out to provide basic data. his research conducted the survey using face to face survey and board survey during about 2 months from Oct. to Nov. in 2009 for users of Bongje Mt., a small-sized mountain at downtown, and Acha Mt., a big-sized mountain at outskirt so as to compare the differences of using behavior by forms and size of urban forest in living area of Seoul. Characteristics of urban forest users, using behavior, demands and satisfaction of facilities and management and pass pattern were set as research items. The thing in common for using behavior is that both genders of main users were in more than 40s~60s. They showed the highest using rate from 7 a.m. to 12 p.m. and high rate for using nearly everyday or visiting two or three times per a week. In addition, it's judged that the accessibility from dwelling area to entrance of urban forest in living area is good and satisfaction for the standard of facilities and their management in forest way was relatively low. For the complement and essential facilities, 'sanitary facilities' showed the highest rate. For the differences of using behavior, most of Bongje Mt. users were residents living within a 2km radius (under the standard of walking) and they moved by average 1.3km. And, they preferred short-time activities of about 24 minutes. On the other hand, main users of Acha Mt. were residents living within a 4km radius (under the standard of walking) and people of other regions. and 60% of them preferred the passage route taking 3hours half over 6km. Through the survey on using behavior of urban forest in living area of Seoul, with different using form and forest size, introduction of using program for main users or managing method of differentiations for introduced facility's management should be properly applied. Especially, urban forest should be systematically managed like park green as expected that residents's using of urban forest will be increased with the increase of leisure time.

• Korean Journal of Environmental Biology
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• v.35 no.3
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• pp.413-425
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• 2017

This manuscript describes the relationship between climate change and forest growth, forest species, carbon stocks, and tree mortality. 1) In the aspect of forest growth, the growth of major coniferous species, including Pinus densiflora, had a negative correlation with temperature. On the other hand, major deciduous oak species, including Quercus variabilis and Quercus mongolica, had a positive correlation with temperature. 2) When considered in the aspect of the forest species distribution, various models commonly showed a decrease in the distribution of coniferous species and an increase in oak species due to climate change in the medium to long term. 3) From the carbon stock perspective, there was a difference in the estimation according to the status of forest management. Most of Korean forests will mature to become over-matured forest after year 2030 and are estimated to produce approximately 410 million ton forest biomass until 2090 with the current cutting regulations for sustainable forest management announced by the Korean Forest Service. 4) In the forest mortality, the mortality rate of the major coniferous species showed a clear tendency to increase higher temperatures while it decreased for the oak species with no verification of statistical significance. Moreover, the mortality of the subalpine coniferous species was projected to progress rapidly. considering the overall impacts described above, there should be a management strategy for coniferous species that are relatively vulnerable to climate change. Moreover, a sustainable forest plan in the aspect of ecosystem services, carbon sequestration and storage, which is linked to global issues such as Sustainable Development Goals, ecosystem services and negative emission.

• Journal of Preventive Medicine and Public Health
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• v.2 no.1
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• pp.5-22
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• 1969

The urban population of our country is rapidly increasing due to many factors of social structure, and sociologists are predicting that the increase rate of the urban population will be over 50% in 1980's. Above all, the population of the capital city of Seoul, is at present more than four millions. Such centring of people in cities, together with the improvement of the standards of living, caused rapid increase in the amount of fuel consumption, and this consumption of fuels became one of the primary sources of the air pollution in cities. Moreover, the heavy traffic, construction of many tall buildings, and the increasing number of new factories due to the industrial development-all these are contributing to make the matter of air pollution worse and worse in the Metropolitan, whose geographical location is quite unfavorable considered from the view point of air pollution. Most homes in Seoul use briquet as fuel, while oils are used in tall buildings. The CO, $SO_2$, and smoke that come from burning of these fuels are a great threat to the health of the urban population. With the purpose of examining the influence of air pollution upon the public health, written inquiries were made upon respiratory diseases, and the carboxyhemoglobin saturation in the blood was measured to determine whether the air pollution may affect the health of the urban population. Method of Health Examination (1) Investigation of Respiratory Diseases Patients' records were examined to figure out the monthly ambulance rate of respiratory patients to the total number of patients treated. On the other hand, by using the questionnaire form approved by the Medical Research Council's Committee on Research into Chronic Bronchitis, investigators interviewed the examinees and inquired into the respiratory symptoms. (2) Measuring of Carboxyhemoglobin Saturation From the ear lobe of the examinees, with the use of the melangeur for the white blood cell counting, blood was taken, and after diluting it ten times with 0.1% $Na{2}CO_{3}$, again diulting it 20 times with 0.5% $Na_{2}\;CO_{3}$, its absorbancy was measured. The following results are obtained from the investigation. (1) It was found out that 7.7% of the total patients under treatment were suffering from upper respiratory infection, acute or chronic bronchitis, bronchial asthma, pulmonary emphysema and bronchiectasis. Of them all, patients with upper respiratory infection numbered the greatest with 4.8% and patients with acute or chronic bronchitis the next with 2.1%, and their monthly ambulance rate was high from December to February during the winter, and from April to May and from September to October during the changeable seasons. (2) The daily ambulance rate of respiratory patients, it was revealed, had a close connection with the concentration of $SO_2$ and CO in the air. (3) It was found out that men were more subject to respiratory disease than women, and both men and women were more liable to the diseases with the advancing of age. (4) People living at Choong-ku with the heavy traffic and in the industrial zones of Yeungdungpo had high frequency of respiratory symptoms. (5) Considered from the view point of occupations, high frequency was found among those without job, with jobs unknown, merchants and intdustrial workers, whose social status was rather low and traffic policemen who were always exposed to the exhaust gas of cars. As for women, the frequency was detected in the order of those from high to low, housewives who were exposed to briquet gas, women with jobs unknown, women without jobs, whose social status was low. (6) Ex-smokers rather than smokers, of both sexes, had higher frequency. As for men, heavy smokers had high frequency, while in women light smokers had rather high frequency which was presumed to be due to their average old age. (7) Men's average of carboxyhemoglobin saturation was 9.48%, while women's was 11.3%, higher than men's. (p<0.05). Age meant no difference in the case of men, but as for women, the saturation was remarkably high between the ages from 20 to 60. (8) No regional difference was detected in the carboxyhemoglobin saturation. (9) The carboxyhemoglobin saturation was found, in the case of men, in the order of office workers, traffic policemen, students, the unemployed, merchants and industrial workers, drivers; and as for women, the order was housewives, office workers, merchants and industrial workers. (10) No significant correlation was found between the carboxyhemoglobin saturation and the concentration of CO detected in kitchens, or between the carhoxyhemoglobin saturation and the passing of time after exposure to briquet gas. No difference of carboxyhemoglobin saturation was detected between smokers and non-smokers, and the degrees of smoking; only, significant negative correlation was found between the passing of time after smoking and the carboxyhemoglobin saturation. It is ture that air pollution causes or aggravates the respiratory diseases, increases the carboxyhemoglobin saturation in the blood, but what seems to be more hazardous to the health is the air polluted by the briquet gas in the kitchens and on-dol rooms rather than the atmospheric air pollution.