• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.73-87
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• 2018

A variety of micro meteorological variables such as air temperature, wind, solar radiation and latent heat at Gwangneung forests (conifer and broadleaved forests) and AWS (Automated Weather Station) of Pocheon urban area were used to quantify the air temperature reduction effect of forests, which is considered to be an eco-friendly solution for reducing the urban heat island intensity during summer. In June, July and August of 2016 and 2017, the average maximum air temperature differences between above and below canopy of forests, and between the forests and urban areas were $-1.9^{\circ}C$ and $-3.4^{\circ}C$ respectively, and they occurred at 17:00. However, there was no difference between conifer and broadleaved forests. The effect of air temperature reduction by the forests was positively correlated with accumulated evapotranspiration and solar radiation from 14:00 to 17:00 and showed a negative correlation with wind speed. We have developed a model to quantify the effect of air temperature reduction by forests using these variables. The nighttime air temperature reduction effect by forests was due to the generation of cold air from radiative cooling and the air temperature inversion phenomenon that occurs when the generated cold air moves down the side of mountain. The model was evaluated in Seoul by using 28 AWSs. The evaluation shows that the air temperature of each district in Seoul was negatively correlated with the area and size of the surrounding tall vegetation that drives vegetation evapotranspiration during the day. During the night, however, the size of the surrounding tall vegetation and the elevations of nearby mountains were the main influencing factors on the air temperature. Our research emphasizes the importance of the establishment and management of urban forests and the composition of wind roads from mountains for urban air temperature reduction.

• Journal of the Korean earth science society
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• v.35 no.7
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• pp.562-571
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• 2014

In the celebration of the $50^{th}$ anniversary of the Korean Earth Science Society, the whole articles published in Journal of the Korean Earth Science Society (JKESS) were quantitatively analyzed. JKESS has played a major role in exchanging academically among earth science education specialists and in educating next generation for the last 36 years since it was founded in 1979. The total number of 1544 articles in thirty five volumes about the earth sciences and the earth science pedagogy has been published by August, 2014, and the number of the yearly published articles has been increasing. Regarding the research area, 69.3% was published in earth sciences and the other 30.7% was in earth science education; the percentage of research articles in geology, atmospheric science, environmental science, oceanography, and astronomy was 55.2, 17.6, 16.0, 6.0, and 5.2%, respectively. The number of research articles on atmospheric science and environmental science has recently been increasing, whereas, earth science education research articles have been" decreasing, which was similar to the pattern seen fifteen years ago. We thought that one of the reasons was related to a new journal named, "Journal of the Korean Society of Earth Science Education" started to publish in December, 2008. The number of articles authored or co-authored with foreigner scholars was totaled 53, which is only 3.4% of the entire number of published articles. It suggests that international advertisement via public relations as well as the development of English homepage be necessary. In order to become an excellent registered academic journal, it is the time to comprehensively discuss how to improve both the quality growth and the quantity of JKESS. According to the Ministry of Education, it is now in its planning stage to convert the current registration system of the academic journals to the autonomous evaluation system in academia. Therefore, we recommend that Journal of the Korean Earth Science Society be prepared for the upcoming future change.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.95-108
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• 1984

In order to see the effect of various factors on the success of grafting of walnut, a modified cleft grafting experiment has been conducted with Juglans sinensis Dode, J. regia (persian walnut), J. regiu (carpathian walnut), J. mandshurica, J. nigra and five cultivars of Carpathian walnut as "HANSEN", "METCALFE" "SCHOOL", "ILL CRATH", "LAKE" in a large green house equipped with automatic environmental control system in which temperature of the grafting bed at $28^{\circ}C$ and 85-100% for humidity during the period of January 1981-June 1983. As results of the experiments, the following facts were observed. 1) Hteroplastic grafting was proved to be more successful than homoplastic grafting with all five species tested among the J. regia (carpathian walnut), J. regia (persian walnut), J. sinensis, J. mondshurica, J. nigra. 2) It was interesting to notice that results hight survival of graft high as 99.33-100% with heteroplastic grafting when "Persian Walnut" and "Carpathian Walnut" was grafted on the stock of J. mandshurica and J. nigra. 3) A statistical significance of 5% Level was recognized in the above stocks among five species of homoplastic grafting with heteroplastic grafting and no significance among the scions. 4) The heteroplastic grafting when five cultivars of Carpathian Walnut as above as was grafted on the stock of Juglans nigra and J. mandshurica resulting high survival of graft as high as 85.33-100%. 5) As conclusion, the heteroplastic grafts of Carpathian Walnut and Persian Walnut was grafted on the stock of Juglans nigra and Jugdans mandshurica, the graft union, between stock and scion completed, in short period and was followed by a vigorous growth as well as "Cross Breeding", or hybrization, became apparent, with different desirable traits which could he used to cultivate a Later generation that combined these characteristics.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.2
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• pp.177-192
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• 2018

The mission of the university is to grow young people who will be responsible for the next generation nation to mature society. In particular, the role of universities in the 4th Industrial Revolution era is to foster creative talents. Therefore, innovative changes are required for existing infusion education and employment-oriented college education contents and teaching methodology. In the high youth unemployment rate, entrepreneurship education is spreading to universities to innovate existing organizations and create new jobs. Until now, however, the effects of university entrepreneurship education have been studied mainly in the field of start-up. Therefore, it is very difficult to study various effects on entrepreneurship education. In this study, empirical analysis of the effect of entrepreneurship training on career preparation behaviors of university students who are about to enter the society is verified. The sample of this study was surveyed from August, 2016, and the questionnaire was applied to 393 university students who selected 5 universities and entrepreneurship education. As a result of the analysis, the ability of communicative communication and creative problem solving cultivated through entrepreneurship education had a positive effect on entrepreneurship and self - efficacy, Entrepreneurship and self - efficacy had a positive (+) positive effect on career preparation behavior. However, cooperative communication ability, creative problem solving ability, and effective work behavior ability by entrepreneurship education were not directly related to career preparation behavior. On the other hand, in verifying the mediating effect of entrepreneurship and self - efficacy, it proved that mediating role of positive communication between collaborative communication ability, creative problem solving ability and career preparation behavior. The implications of this study are as follows This study examines the effects of university entrepreneurship education on career preparedness behaviors.In other words, the university proved the direct effect and the mediating effect that affects positively (+) effect on career preparation behaviors by encouraging entrepreneurship and self - efficacy, rather than quantitative extension based on competency. Also, the implication of the parameters (entrepreneurship, self - efficacy) as a key variable for the effect and performance of career preparation behavior was derived.It also suggests that it is necessary to improve the creativity ability of entrepreneurship education so that it can have a direct and meaningful influence on career preparation behavior. First of all, it is urgent to develop a qualitative evaluation index for entrepreneurship education in order to measure these effects. Therefore, further study is required to verify the various implications for future entrepreneurship education, as well as the implications that entrepreneurship education is indispensable for the preparation of university students' careers.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.210-218
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• 2015

Melon leaves showing yellowing symptoms were analyzed using electron microscopy and RT-PCR for major cucurbit-infecting-viruses (CMV, MNSV, CGMMV, SqMV, WMV, KGMMV, PRSV and ZYMV) reported in Korea, but these viruses were not detected. As the result of further analysis by next-generation sequencing (NGS), the virus was identified as Cucurbit aphid-borne yellows virus (CABYV), and then confirmed by RT-PCR using CABYV-specific primers. When photosynthetic capacity was measured based on chlorophyll fluorescence yield (ChlFY), the leaves of the diseased plants showed $4.09{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, which was one-third of the readings observed for unaffected normal plants ($12.36{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). The root functions of plants affected by leaf yellowing symptoms (LYS) was $0.28mg{\cdot}g^{-1}$, about half that measured for the normal unaffected plants ($0.48mg{\cdot}g^{-1}$). Cytological observations revealed that there were no morphological differences in the palisade parenchyma and mesophyll spongy cells of the leaves between the diseased and the normal plants. However, the same leaf cells of the affected plants contained more starch granules compared to those of the normal, unaffected plants. We conclude that the LYS of muskmelon is not merely a physiological disorder but a viral disease caused by CABYV and spread by aphids.

• Korean journal of food and cookery science
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• v.16 no.4
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• pp.342-351
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• 2000

This study aimed for exploring the best recipe of Sangjabyung to increase its utility value and to develop traditional Korean rice cake industry for next generation. The best recipe was determined after several tests such as sensory evaluation and mechanical measurements for texture, moisture content, and colorimetry. The samples prepared with 5% of acorn starch with honey showed the best scores in sensory evaluation for color and flavor, 5% of acorn powder with sugar for grain, 15% of acorn powder with sugar for moistness and chewiness, 15% of starch with honey for sweetness, and non-glutinous rice flour mixed with 10% of acorn powder and sugar for overall quality. Every item except for flavor was significantly different from that of control (P<0.05). The highest score for springiness was obtained from the samples prepared with 10% of acorn starch with sugar, cohesiveness with 5% of acorn starch with sugar, chewiness with 15% of acorn starch with honey, gumminess with 15% of acorn starch with honey, adhesiveness with 5% of acorn starch with honey, and hardness with 15% of acorn starch with honey. All items were significantly different from that of control (P<0.05). The overall quality of sensory evaluation was correlated with moistness(P<0.05), springiness, cohesiveness(P<0.01), and adhesiveness(P<0.01) in mechanical test. Moisture contents of rice flour, acorn starch, and acorn powder were 32.93%, 8.52%, and 13.26%, respectively. The desirable moisture content in Sangiabyung was 44.11% in the case of using rice flour with acorn starch or 44.33% for rice flour with acorn powder. As a result of colorimetry, the best L, a, and b values were obtained from the rice cakes with 5% acorn starch and oligosaccharides, with 15% of acorn powder and sugar, and with 15% of acorn starch with oligosaccharides, respectively. Overall. the most desirable recipe for Sangjabyung was determined as rice flour 315 g, acorn starch or acorn powder 35 g, sugar 60 g, salt 3.5 g, and water 130 ml.

• Pediatric Infection and Vaccine
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• v.19 no.1
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• pp.12-18
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• 2012

Purpose : This study attempted to investigate the frequency, duration, and risk factors of antibiotic-associated diarrhea (AAD) in infants hospitalized due to febrile urinary tract infection (UTI). This is a basic research on the probiotics used in the prevention and treatment of AAD in infants. Methods : Medical records of the infants aged 3-6 months hospitalized in Gachon University Gil Hospital from January 2008 to September 2010 due to the febrile UTI were retrospectively reviewed. The episodes of loose or watery stool were investigated for frequency, onset, and duration. Those who had AAD and those who did not (non-AAD) were compared. The antibiotic regimens and the episodes of diarrhea were investigated in AAD group. Result : Total 147 infants were included. Fifty-four (36.7%) showed AAD. Intravenous third-generation cephalosporin ($3^{rd}$ CS) single therapy was used for 102 patients (69.4%), the $3^{rd}$ CS and non-$3^{rd}$ CS combination therapy for 24 (16.3%), and non-$3^{rd}$ CS combination therapy for 21 (14.3%). There was no significant difference in the dose of cefotaxime between AAD and non-AAD group (P=0.601). According to the antibiotic therapies above, in AAD group, there was no significant difference in the onset and duration of diarrhea respectively (P=0.717, P=0.830). Although the frequency of diarrhea was higher for the $3^{rd}$ CS and non-$3^{rd}$ CS combination therapy subgroup with $9.25{\pm}5.30$ times/day than the other two subgroups ($7.58{\pm}2.97$ times/day in $3^{rd}$ CS single therapy subgroup, $6.75{\pm}4.40$ times/day in non-$3^{rd}$ CS combination therapy subgroup), there was no statistical significance (P=0.078). Conclusion : AAD seems common to the infants aged 3-6 months with febrile UTI, regardless of regimen and amount of antibiotics in usual dosage. Further research on the effects of probiotics used in the prevention and treatment of AAD in infants is warranted.

• Journal of Korea Water Resources Association
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• v.44 no.4
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• pp.315-325
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• 2011

There are not many practical measures to solve a water conflict, when a hydromorphologically asymmetric situation in international rivers exists whereby downstream users may not affect upstream users but upstream users do cause downstream impacts. In taking advantage of this merit, North Korea has built Imnam Dam in upstream of North Han River and uses water for trans-basin hydropower generation. As an impact of this dam South Korean' area as a downstream user has been suffered from water deficit and dry river. It is very critical for South Korea to solve a key problem such as water allocation for water supply and river maintenance. Therefore, this study is aim to suggest alternatives for equitable water allocation in consideration of special circumstances between the South and the North. For this, reviewing the allocation methods of water rights is carried using lessons obtained from international river cases. The results show that the minimum desired streamflow is calculated at 7.3 $m^3/sec$; water budget analysis by the equitable distribution of streamflows at the border line of the North Han River, the difference in water supply deficiency is at 3.7 $m^3/sec$ before and after Imnam Dam; in the determined distribution method, the difference in water deficiency is at 11.38 $m^3/sec$. These results show that South Korea should be secured 11.38 $m^3/sec$ from North Korean's Imnam Dam in respective of water use right and sound river maintenance.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.121-139
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• 2014

Predicting corporate failure has been an important topic in accounting and finance. The costs associated with bankruptcy are high, so the accuracy of bankruptcy prediction is greatly important for financial institutions. Lots of researchers have dealt with the topic associated with bankruptcy prediction in the past three decades. The current research attempts to use ensemble models for improving the performance of bankruptcy prediction. Ensemble classification is to combine individually trained classifiers in order to gain more accurate prediction than individual models. Ensemble techniques are shown to be very useful for improving the generalization ability of the classifier. Bagging is the most commonly used methods for constructing ensemble classifiers. In bagging, the different training data subsets are randomly drawn with replacement from the original training dataset. Base classifiers are trained on the different bootstrap samples. Instance selection is to select critical instances while deleting and removing irrelevant and harmful instances from the original set. Instance selection and bagging are quite well known in data mining. However, few studies have dealt with the integration of instance selection and bagging. This study proposes an improved bagging ensemble based on instance selection using genetic algorithms (GA) for improving the performance of SVM. GA is an efficient optimization procedure based on the theory of natural selection and evolution. GA uses the idea of survival of the fittest by progressively accepting better solutions to the problems. GA searches by maintaining a population of solutions from which better solutions are created rather than making incremental changes to a single solution to the problem. The initial solution population is generated randomly and evolves into the next generation by genetic operators such as selection, crossover and mutation. The solutions coded by strings are evaluated by the fitness function. The proposed model consists of two phases: GA based Instance Selection and Instance based Bagging. In the first phase, GA is used to select optimal instance subset that is used as input data of bagging model. In this study, the chromosome is encoded as a form of binary string for the instance subset. In this phase, the population size was set to 100 while maximum number of generations was set to 150. We set the crossover rate and mutation rate to 0.7 and 0.1 respectively. We used the prediction accuracy of model as the fitness function of GA. SVM model is trained on training data set using the selected instance subset. The prediction accuracy of SVM model over test data set is used as fitness value in order to avoid overfitting. In the second phase, we used the optimal instance subset selected in the first phase as input data of bagging model. We used SVM model as base classifier for bagging ensemble. The majority voting scheme was used as a combining method in this study. This study applies the proposed model to the bankruptcy prediction problem using a real data set from Korean companies. The research data used in this study contains 1832 externally non-audited firms which filed for bankruptcy (916 cases) and non-bankruptcy (916 cases). Financial ratios categorized as stability, profitability, growth, activity and cash flow were investigated through literature review and basic statistical methods and we selected 8 financial ratios as the final input variables. We separated the whole data into three subsets as training, test and validation data set. In this study, we compared the proposed model with several comparative models including the simple individual SVM model, the simple bagging model and the instance selection based SVM model. The McNemar tests were used to examine whether the proposed model significantly outperforms the other models. The experimental results show that the proposed model outperforms the other models.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.59-66
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• 2020

Recently, cultivation and management technologies have been needed to adapt due to climate change, which is causing abnormal weather conditions. One technique is to increase the utilization of evergreen broad-leaved species with high ornamental value. A total of five treatments were installed (1m×22.5m), including 60g/㎡ and 80g/㎡ using two types mulching material with an overlapping and hole-drilling mulching method and these were compared to un-mulching treatment a total of planted 92㎡ attheWol-aTestSiteForestattheForestforBiomaterialsResearchCenterinJinju-si, Gyeongsangnam-dofor 10monthsusing3-years-oldQuercusglaucaThunb. In comparison with the control site, the 60g/㎡ overlapping method was about 1.9 times higher than the root collar diameter, but there was no statistical significance between the treatments. Healthy seedlings were found to meet these conditions due to high biomass values and below and T/R ratios of 3.0 or lower and H/D ratios of 7.0 or lower. Comparing the values of LWR, SWR, and RWR, which can be evaluated for seedling due to the mulching treatments, as compared to the control, the growth of the ground areas including leaves and stems was enhanced, but the growth of the underground areas containing roots tended to have high control values. Based on this, the SQI value, which can be evaluated for the comprehensive quality of seedlings, was found to be significantly different between the control site and the mulching treatment sites, confirming that the growth and growth improvement effects were achieved with mulching treatments. The chlorophyll content analysis showed that there was a significant difference from the control site, and it was judged that weed generation in the control acted as an environmental stress, causing a decrease in chlorophyll content. It was found that the overlapping 80g/㎡ of polypropylene mulching material generated about 4 times fewer weeds than the control, and the manpower required for the mulching test field and weeding were equal at 3.3 people/100㎡/1 day. Mulching treatments have demonstrated a significant difference in the promotion of growth and quality of the seedlings and are judged as an alternative that can reduce the economic burden incurred by the purchase of the supplies and the manpower required to weed forestry plantations.