• Journal of the Korea Academia-Industrial cooperation Society
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• 제19권1호
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• pp.300-310
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• 2018

The purpose of this study is to compare the change of Well-Dying awareness and decision of university student before and after taking the course of death study. A questionnaire survey was conducted for university students 93 before education, 117 after education who participated in the Death Studies related lectures at Daejeon Metropolitan City for 15 weeks from August to December 2016. The general characteristics of survey are gender, age. grade, major, marriage condition, religion, family member living together and health status. Four items on the perception aspect of death, five items on the aspect of acceptance of death, seven items of death decision and twelve items for death education's interest and importance were configured as a reference scale. The statistical method carried out the chi-square test, the independent sample t-test, and the decision tree analysis. Based on the decision tree, At the time of preparation for death(cancer patient, terminal patient, etc.) and the elderly(65 years old or older), the education transition rate was 66.7%. But After education, 65.3% of the respondents were in adult, middle and high school, under elementary school, university, and graduate school, which showed a significant difference. Therefore we are looking for death education's effectiveness and setting directions for education's period and contents. the negative viewpoints and worries about the implementation of death education at elementary, middle and high schools and universities are resolved and the death education will positively affect the change of attitude of students.

• Journal of the Korea Society of Computer and Information
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• 제17권7호
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• pp.167-174
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• 2012

Data mining technique can be adapted to analysing Employment information in order to discover valuable information out of large data. As the issue employment such as jobless of college graduate, recruitment for women, recruitment for elders etc. became social problem, there are many efforts of various public employment services and studies. The factors that affects the college graduate's employment type (regular, temporary, daily) can be used to guide employment and to prepare employment for college students. In analyzing large number of attributes and the huge amount of data elements, regular statistical methods faces their limitation; therefore, data-mining technique is more suitable for the dataset of about 170 attributes and 20,000 elements. We divide the factors that may affect the employment type into personal factor, school factor, company factor, and experience factor; decision tree algorithm is used to find out the interesting relationship between the attributes of the factors and employment type. Personal factors such as the income of parents and marital status were the most affective factors to the employment type. The learned decision tree was able to classify the employment type with 87% of accuracy. We also assume the level of the school affects the employment type of the graduates.

• Journal of Korean Society of Forest Science
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• 제88권2호
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• pp.195-204
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• 1999

To improve nut production and timber quality in a plantation, crown shape controls were suggested for Korean white pines (Pinus koraiensis) under age class III through the analyses of the crown shape controls for seed orchard trees in several species, of crown status of controlled and uncontrolled trees in a Korean white pine seed orchard, and of growth characteristics of plantation trees under age class III. For nut production from the small trees less than 8 m, modified leader type can be applied by cutting the central leader and all branches below 1 m and keeping 4~5 nodes with 3~4 whorled branches a node locating 1 m apart. Trees with a 4~8 m long trunk below the first living branch are shaped into trees for nut and timber production, which have a 4~8 m long knotless stem and a modified leader type crown with 4~5 nodes with 3~4 whorled branches a node at a distance of 1 m. Trees, showing the first living branch at or above 9 m from the surface, are pruned severely for timber production and result in a central leader type containing two fifths of the initial crown. It is advisable to remove the leader and the branches when collecting cones or after/during October to take advantage of easy labor and little resin while cutting. After stem cut, branches showing apical dominance are to be cut to control height when necessary. The removal of the uppermost node may be needed to control the crown shape several years after the initial stem-cut.

• Knowledge Management Research
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• 제21권3호
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• pp.105-121
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• 2020

With regard to the development of new drugs, what is most important for a Korean Biotech, where no global sales network has been established, is decision-making related to out-licensing of new drugs. The probability of success for each clinical phase is different, and the licensing amount and its royalty vary depending on which clinical phase the licensing contract is made. Due to the nature of such a licensing contract and Biotech's weak financial status, it is a very important decision-making issue for a Biotech to determine when to license out to a Big Pharma. This study defined a model called 'optimal timing for out-licensing of new drugs' and the results were derived from the decision tree analysis. As a case study, we applied to a Biotech in Korea, which is conducting FDA global clinical trials for a first-in-class new drug. Assuming that the market size and expected market penetration rate of the target disease are known, it has been shown that out-licensing after phase 1 or phase 2 of clinical trials is a best alternative that maximizes Biotech's profits. This study can provide a conceptual framework for the use of management science methodologies in pharmaceutical fields, thus laying the foundation for knowledge and research on out-licensing of new drugs.

• Journal of the Korean Institute of Landscape Architecture
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• 제45권5호
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• pp.1-13
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• 2017

This study was intended to provide management directions through the provision of tree spatial information as basic data for the preservation of Gyerim(legal historical site), which is located in Gyeongju city, Gyeonsangnam-do, Korea. As a result of the survey of the entire forest, there are a total of 25 species and 510 individuals growing trees. Of these species, 14 species are native and 14 are introduced species. Apart from Sophora japonica, Zelkova serrata, Celtis sinensis, most of the introduced species were adopted without historical basis after designation as a historical site. By a ratio of 36% to introduced species(including 3% of naturalized species; Ailanthus altissima), the historical heritage was significantly damaged. Gyerim, which has over 2,000 years of history, has a total 15 individuals(2.9%) large trees(over 100cm DBH). Ten of these are Salix glandulosa, and in the past, most of this area was considered a Salix glandulosa forest. Currently, however, there are many small trees(under 20cm DBH) for the next generation of growth and the Salix glandulosa forest will continue to decline. Furthermore, most small trees were afforested, so the historicity and place features as a mythological forest will quickly fade.

• Korean Journal of Organic Agriculture
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• 제20권1호
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• pp.37-48
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• 2012

This study was conducted to evaluate the effects of ground cover treatments on the nutrient contribution in a 'Niitaka' pear ($Pyrus$ $pyriforia$) orchard. Treatments included; 1) sod culture, 2) winter cover crop [ryegrass+hairy vetch], and 3) winter [ryegrass+hairy vetch]+summer [greensolgo (sudan grass ($Sorghum$ $bicolor$ L.))+ nemajanghwang (crotalaria ($Crotalaria$ $juncea$ L.)] cover crops. Ryegrass and hairyvetch were seeded with 6.4 kg/10a and 3.0 kg/10a, respectively, on October 17 of 2008, and greensolgo and nemajanghwang were seeded with 2.0 kg/10a and 3.0 kg/10a, respectively, on June 4 of 2009 at a diligent farmer in Boseong in Chonnam. Winter+summer cover crops provided greater amounts of dry weight, followed by winter cover crop and sod culture. The difference of amounts of dry weight from the ground covers affected to the levels of total N, P, and K contents, which were greater nutrient levels than those of recommended nutrient requirement for satisfying 10- to 12-year-old pear tree growth. Greater amounts of dry weight from the ground covers increased organic matter and concentrations of K and Mg in soil. Foliar nutrient concentrations, as an indicator of nutrient status of a tree, were not affected by application of ground cover treatments.

• Korean Journal of Environment and Ecology
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• 제24권6호
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• pp.638-647
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• 2010

This study was performed in order to analyze influences the actual vegetation between the communities of Pinus densiflora and Quercus mongolica in southern Korea to the species composition of the seed bank in the top soil. The soil samples were collected from the studied plots and transported to the Experimental Glasshouse at Department of Landscape Architecture, Yeungnam University and examined the germinated species individual numbers with species composition and germinated individual numbers by species. The overall germination status was the highest in the herbaceous layers than the layers of tree, sub-tree and shrub, respectively. There were no significantly different between numbers of species and individuals and between actual vegetation and seed bank in the two communities. The woody species marked in the seed bank as a pioneer or edge species than in the two communities which are in the stage of mid or late successional species. Although the plant species in the herbaceous layers was highly influenced to the species composition of the seed bank, but no significantly different was showed within the same forest zone and latitudes of Korean peninsula. As the pioneer or edge species of the actual vegetation possibly will be higher the buried in the top soil layer and this phenomenon will influence overall species composition in the seed bank population.

• Journal of Korean Society of Water and Wastewater
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• 제35권6호
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• pp.417-424
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• 2021

Algal bloom is an ongoing issue in the management of freshwater systems for drinking water supply, and the chlorophyll-a concentration is commonly used to represent the status of algal bloom. Thus, the prediction of chlorophyll-a concentration is essential for the proper management of water quality. However, the chlorophyll-a concentration is affected by various water quality and environmental factors, so the prediction of its concentration is not an easy task. In recent years, many advanced machine learning algorithms have increasingly been used for the development of surrogate models to prediction the chlorophyll-a concentration in freshwater systems such as rivers or reservoirs. This study used a light gradient boosting machine(LightGBM), a gradient boosting decision tree algorithm, to develop an ensemble machine learning model to predict chlorophyll-a concentration. The field water quality data observed at Daecheong Lake, obtained from the real-time water information system in Korea, were used for the development of the model. The data include temperature, pH, electric conductivity, dissolved oxygen, total organic carbon, total nitrogen, total phosphorus, and chlorophyll-a. First, a LightGBM model was developed to predict the chlorophyll-a concentration by using the other seven items as independent input variables. Second, the time-lagged values of all the input variables were added as input variables to understand the effect of time lag of input variables on model performance. The time lag (i) ranges from 1 to 50 days. The model performance was evaluated using three indices, root mean squared error-observation standard deviation ration (RSR), Nash-Sutcliffe coefficient of efficiency (NSE) and mean absolute error (MAE). The model showed the best performance by adding a dataset with a one-day time lag (i=1) where RSR, NSE, and MAE were 0.359, 0.871 and 1.510, respectively. The improvement of model performance was observed when a dataset with a time lag up of about 15 days (i=15) was added.

• Journal of Korean Society of Forest Science
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• 제112권4호
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• pp.405-416
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• 2023

In this study, the sustainability of Abies nephrolepis in the presence of Tripterygium regelii was analyzed. To accomplish this, a field survey of140 stands was conducted. Based on the presence or absence of T. regelii, as well as the layer in which it was present (where appropriate), the type of T. regelii presence wasclassified as follows: TP type, indicating the presence of T. regelii in the tree and sub-tree layers; SP type, indicating its presence in the shrub layer; and A type, indicatingits absence from all layers. The indicator species analysis revealed T. regelii to be an indicator species of the TP type and SP type. The MRPP test was used to examine the differences among the types. Moreover, the seedling and DBH class analysis indicated there to be a difficulty in terms of the status competition, as the number of young trees generated by A. nephrolepis was the lowest in the TP type. The findings of this study enhanced our understanding of the vegetation structure of A. nephrolepis, thereby contributing to efforts concerningits conservation and management.

• Sim-seong Yeon-gu
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• 제25권2호
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• pp.123-162
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• 2010

The author tried to analyse a Korean fairy tale "the traveller and the fox". The essence of the story is as follows; A traveller who was wandering in mountains found a house with a light. There was a beautiful woman who was very kind to give food and shelter. But she was a fox that tried to kill him with a knife. He asked her to bring a basket of water and he broke the wall with it to run away. The fox chased and he fell down a cliff to ride on the back of a tiger. The tiger ran into a cave and give him to her babies as a prey. He killed them by throwing stones and climbed a tree out of the cave. There came foxes and the tiger and they killed each other. He came back to the village with the fur of the foxes and the tiger. The author tried to understand the contents of the story symbolically and interpret them from the perspective of analytical psychology. On conclusion, the traveller was on the individuation process and experienced the negative anima (the fox) and the negative mother archetype (the tiger) and its negative subsidiaries (the tiger's babies). He tried to be consciously alert and paid continuous attention so that he could get out of the status and get new insight. During this process, it was meaningful that he could actively get an appropriate aid of positive mother archetype and Self symbolized by the water and the tree respectively.