• Journal of Environmental Science International
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• v.23 no.6
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• pp.1075-1083
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• 2014

The objective of this study was to evaluate the effect of cutting types on microclimate and growth characteristics of afforested tree in Quercus acutissima stand after different types of cutting. The difference in temperature reaching $5.2^{\circ}C$ was shown in between clear cutting and selective cutting treatments. On July and August days with temperatures more than $35^{\circ}C$ often appeared in clear cutting stand. The values of VPD in July and August were higher than those in other months. Maximum VPD of 3.99 kPa was shown in clear cutting stand on May 23 as a prolonged rainless days appeared. However, VPD in selective cutting stand always stayed under 3.0 kPa throughout growing season. A higher intensity was shown in clear cutting and strip clear cutting stands, reaching to more than $1,600{\mu}mol\;m^{-2}s^{-1}$ at midday on early August, while that in selective cutting stand stayed about 1,500. In relative growth rate selective cutting stand showed a significantly higher relative growth rate in plant height than those in other cutting stands (p<0.05). The number of leaf in current-year branches significantly increased in selective cutting stand, whereas no increase was shown in clear cutting and strip clear cutting stands (p<0.05). In addition, relative elongation rate of current year branch also showed higher values in selective cutting stand compared with that in strip clear cutting stand (p<0.05). However, leaf mass per unit area (LMA) was higher in order of strip clear cutting, clear cutting, and selective cutting stands. From these results it is concluded that environmental conditions in clear cutting and strip clear cutting stands during growing season are more stressful to afforested tree species, resulting in lower relative growth in plant height, elongation of current-year branches, and leaf number per branch compared with those in selective cutting stand. Consequently, more data must be accumulated in the field to find out best cutting type in plantation considering the adaptational characteristic of each tree species varies with species and life span of tree is long.

• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.431-439
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• 2009

These days the amount of demolished concrete waste has been increasing due to reconstruction and redevelopment of aged buildings. So the use of recycled aggregates is recommended to solve environmental problems. Some investigations have been carried out to study the flexural behavior of reinforced concrete beams with recycled aggregates. But these have some limitation due to the use of low quality recycled aggregates and small-scale specimens in the laboratory. The purpose of this experimental study is to evaluate the flexural behavior of simply supported RC beams subjected to four-point monotonic loading and made with recycled aggregates. Seven full-scale RC beams were manufactured with different replacement level of recycled aggregates. The main parameters of the study are combination of aggregates. From the test results, the flexural behavior of the beam is described in terms of crack patterns and failure modes. And the flexural strength of RC beam with different types of recycled coarse aggregates and recycled fine aggregates is compared with the provision of KCI code.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.455-462
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• 2013

The objectives of this study were to compare soil physical and chemical properties and early growth of Pinus densiflora and Larix kaempferi seedlings in harvested Larix kaempferi and Pinus rigida stands. Study stands were located in harvested L. kaempferi (Yeongju) and Pinus rigida (Wonju) plantations. Seedlings of L. kaempferi (1-1) and P. densiflora (1-0) were planted in April, 2008, Yeongju. Also, seedlings of L. kaempferi (1- 1) and P. densiflora (1-1) were planted with the density of 3,000 seedlings/ha in April, 2010, Wonju. We analyzed soil physical and chemical properties and the relative growth rate of seedlings using diameter at root collar and seedling height. Soil organic matter, total nitrogen and available phosphorus concentrations in harvested P. rigida stand were significantly higher than those in harvested L. kaempferi stand. The relative growth rate of P. densiflora seedlings with former stands were not significantly different. The relative growth rate of diameter at root collar of L. kaempferi seedling in harvested P. rigida stands were significantly higher than that in harvested L. kaempferi stand. Higher concentrations of organic matter, total nitrogen and available phosphorus in harvested P. rigida stand was probably positively affect to the early growth of seedlings.

• Survey Research
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• v.10 no.3
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• pp.59-83
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• 2009

The purpose of this study is to understand why female labor force participation rates decline in early times after their marriage. Data were derived from the 4th(2001) to 9th(2006) Korea Labor & Income Panel Study. 194 Korean married women in twenties and thirties who had a job before marriage were analyzed. Survival analysis was used to explore the first labor force exit of married women longitudinally. The major findings are as follows. First, nearly half of them went away from labor market in the first 3 years after marriage. Second, child birth was the most significant factor in predicting women's labor force exit. Married women's employment discontinuity tend to be lowered after child birth, with working hour decreasing, and with the number of available family-friendly policies increasing. Married women's income encouraged them to hold on their career, though husband's income and household income were not significant. Third, married women tended to leave their job before giving birth. Women who remained in the labor market at child birth or until a year after birth were inclined to continue their job thereafter. Fourth, maternity leave and childcare leave diminished the probability of employment discontinuity. Many working wives could not use a maternity leave or childcare leave. This study shows married women usually underwent labor market exit in their newly married time. They cannot help facing conflict between the role of mother's and a worker's. Family-friendly policies could encourage working wives to rear child and continue work at the same time. The findings of this study could serve as fundamental material for further studies and would be a key to find effective solution for problematic issues on reconciling work and family.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.69-70
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• 2013

IPCC (International Panel on Climate Change) reported that the arctic sea-ice extent has been decreased by 2.7% per decades since satellite observations in 1978. The decreased sea-ice extent has gained an international attention due to its economical benefits from the NSR (Northen Sea Route). The NRS - not a clearly defined single route, but a number of alternative routes across the top of Russiahas a 37 % reduction in sailing distance, comparing to the SSR (Southen Sea Route) passing thourgh the Suez Canal. Sailing days are consequently reduced from 30 days to 20 days. Also, it is estimated that the Northen Sea has 20 to 25% of world's oil resources and occupies 40% of the world's fishery production. As Republic of Korea was admitted as an observer to the Arctic Council on May 15, 2013, there has been increasing needs to explore new route in the Northen Sea. In this situation, Korea Institute of Ocean Science & Technology (KIOST) is preparing a plan for the development of Arctic-circle Ocean Environmental Information System to support the ice navigation and resource exploration in the Arctic. We will introduce a conceptual design of a satellite-based ice navigation supporting system for the northern sea route.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.3
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• pp.102-112
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• 2013

In this paper, two step processing method of contour extraction and complement which contain hexagonal shape for low contrast and noisy images is proposed. This method is based on the combination of Laplacian-Gaussian filter and an idea of filters which are dependent on the shape. At the first step, an algorithm which has six masks as its extractors to extract the hexagonal edges especially in the corners is used. Here, two tricorn filters are used to detect the tricorn joints of hexagons and other four masks are used to enhance the line segments of hexagonal edges. As a natural image, a corneal endothelial cell image which usually has regular hexagonal form is selected. The edge extraction of hexagonal shapes in corneal endothelial cell is important for clinical diagnosis. The proposed algorithm and other conventional methods are applied to noisy hexagonal images to evaluate each efficiency. As a result, this proposed algorithm shows a robustness against noises and better detection ability in the aspects of the output signal to noise ratio, the edge coincidence ratio and the extraction accuracy factor as compared with other conventional methods. At the second step, the lacking part of the thinned image by an energy minimum algorithm is complemented, and then the area and distribution of cells which give necessary information for medical diagnosis are computed.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.85-94
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• 2006

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in sinseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by CC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with $70\%$ acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography $(3\times30cm)$ packed with florisil $(30g,\;130^{\circ}C,\;12hrs)$. The final extract was concentrated in a rotator evaporator at $40^{\circ}C$ until dryness. Then the residue was redissolved to 2ml with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over $1\~10{\mu}g/ml$. The recovery tests were ranged from $70.7\%$ to $115.2\%$ with standard deviations between 0.3 and $5.7\%$ of the standard spiked to the ginseng extract sample (Group $I\~IV$). The limit of detection (LOD) ranged from 0.001 to $0.099{\mu}g/ml$ (Group $I\~IV$). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.570-586
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• 2015

The purpose of this study is to analyze the effects of middle-aged retirement planning on individual's quality of life and overall satisfaction, and moderating effects of social and psychological sense of crisis, and the differences of measured variables in the demographic characteristics. Retirement planning that may be the most important factor in the country's social costs is aimed to provide a basis for fixing the interest in advance of retirement planning training and retirement. The subjects are workers who live in the Seoul metropolitan area and Gyonggi-do. Total sample size is 350, then 335 samples were collected on the data. The results of this study can be summarized as follows. First, house ownership and education level among demographic variables affects satisfaction of their life. People who do not own a house shows higher satisfaction, and higher education level affects satisfaction positively. Second, satisfaction is affected by transition to rest negatively, on the other hand, it is affected by expect of new beginning positively. Besides, No moderating effect of social and psychological crisis showed that negative life evaluation role to the independent variables. Third, cognitive information is affected by transition to rest and imposed disruption positively. Besides, job dissatisfaction adjusts between them. Fourth, improvement of life quality is not affected by expect of the retirement planning. On the other hand, there is not moderating effects of social and psychological sense of crisis.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.628-638
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• 2014

The aim of this study was to explore the reliability and validity of the Korean version of the Recovery Assessment Scale in psychiatric patients. The original RAS was translated into Korean and the content was verified through back-translation procedures. This study included 142 patients who had chronic mental illness and were aged 18 or older. The subjects were assessed by using RAS-K, the 12-item Dispositional Hope Scale(DHS), the 28-item Mental Health Recovery Measure(MHRM), the 32-item Behavior and Symptom Identification Scale (BASIS-32). In the reliability test, Crobach's a coefficient and test-retest reliabilities were 0.92 and 0.79, respectively, indicating that the RAS-K has good internal consistency. In the analysis of the concurrent validity of the RAS-K, there were significant correlations between the RAS-K and DHS(r=.675, p<0.01), and between the RAS-K and MHRM(r=.816, p<0.01), but lower correlations with symptoms and clinician-related measures of psychiatric functioning. Factor analysis resulted in a five factor solution accounting for 62.476% of the common variance. Our study indicates that the RAS-K is an appropriate instrument to assess recovery in Korean psychiatric patients.

• Journal of dental hygiene science
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• v.15 no.4
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• pp.430-436
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• 2015

This study examined the correlation of educational experience with practical behavior in infection control. Subjects were 152 dental hygienists in Gwangju from September 15 to October 5, 2015. The ratio of dental hygienists educated on infection control was higher in those worked in dental care with 2~4 dentist for 2~5 years and lower in those worked in dental cared with 1 dentist for 2~5 years (p<0.05, p<0.001). The dental hygienists with or without educational experience in infection control exhibited the highest activity rate in hand wash and the lowest in face protection. Barrier in health belief, was lower with the need for education in infection control among the factors affecting on the activity in infection control. The activity was higher with susceptibility and cue to action (p<0.05). Based on the results, education program on infection control should be developed, and applied periodically and obligatorily for dentist and all staffs of dental care to remove susceptibility and barrier, and to enhance cue to action. This will result the effective control of infection by elevating the health belief.