• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.259-270
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• 2020

Extreme weather events, such as heat and drought, have occurred frequently over the past two decades. This has led to continuous reports of cases of forest damage due to physiological stress, not pest damage. In 2014, pine trees were collectively damaged in the forest genetic resources reserve of Sogwang-ri, Uljin, South Korea. An investigation was launched to determine the causes of the dieback, so that a forest management plan could be prepared to deal with the current dieback, and to prevent future damage. This study aimedto 1) understand the topographic and structural characteristics of the area which experienced pine tree dieback, 2) identify the main causes of the dieback, and 3) predict future risk areas through the use of machine-learning techniques. A model for identifying risk areas was developed using 14 explanatory variables, including location, elevation, slope, and age class. When three machine-learning techniques-Decision Tree, Random Forest (RF), and Support Vector Machine (SVM) were applied to the model, RF and SVM showed higher predictability scores, with accuracies over 93%. Our analysis of the variable set showed that the topographical areas most vulnerable to pine dieback were those with high altitudes, high daily solar radiation, and limited water availability. We also found that, when it came to forest stand characteristics, pine trees with high vertical stand densities (5-15 m high) and higher age classes experienced a higher risk of dieback. The RF and SVM models predicted that 9.5% or 115 ha of the Geumgang Pine Forest are at high risk for pine dieback. Our study suggests the need for further investigation into the vulnerable areas of the Geumgang Pine Forest, and also for climate change adaptive forest management steps to protect those areas which remain undamaged.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.181-186
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• 1996

This experiment was conducted at National Yeongnam Agricultural Experiment Station in 1995 to identify effects of early flooding in dry seeded rice on rice growth and weed occurrence. The early flooding of emergence date and the 2-leaf stage were not differed significantly on seedling stand, seedling growth of rice and plant characteristics associated with lodging compared to flooding of the 4-leaf stage. However, weed occurrence resulted in 39-61% suppression. Most predominant weed regardless of flooding times was Echinochloa crus-galli, followed by Aneilema japonicum. The Aneilema japonicum, in general, was higher occurrence with earlier flooding, while dry land weeds such as Digitaria sanguinalis, Stellaria alsine etc. reduced. Grain yield of early flooding at emergence date and the 2-leaf stage was higher by 2-5% than that of the 4-leaf stage due to better grain filling ratio and heavier 1,000 grain weight.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.2
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• pp.36-49
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• 2019

The objectives of this study were to extract "Field Survey Based Infection Tree of Pine Wilt Disease(FSB_ITPWD)" and "Object Classification Based Infection Tree of Pine Wilt Disease(OCB_ITPWD)" from the Research Forest at Kangwon National University, and evaluate the spatial distribution characteristics and occurrence intensity of wood infested by pine wood nematode. It was found that the OCB optimum weights (OCB) were 11 for Scale, 0.1 for Shape, 0.9 for Color, 0.9 for Compactness, and 0.1 for Smoothness. The overall classification accuracy was approximately 94%, and the Kappa coefficient was 0.85, which was very high. OCB_ITPWD area is approximately 2.4ha, which is approximately 0.05% of the total area. When the stand structure, distribution characteristics, and topographic and geographic factors of OCB_ITPWD and those of FSB_ITPWD were compared, age class IV was the most abundant age class in FSB_ITPWD (approximately 55%) and OCB_ITPWD (approximately 44%) - the latter was 11% lower than the former. The diameter at breast heigh (DBH at 1.2m from the ground) results showed that (below 14cm) and (below 28cm) DBH trees were the majority (approximately 93%) in OCB_ITPWD, while medium and (more then 30cm) DBH trees were the majority (approximately 87%) in FSB_ITPWD, indicating different DBH distribution. On the other hand, the elevation distribution rate of OCB_ITPWD was mostly between 401 and 500m (approximately 30%), while that of FSB_ITPWD was mostly between 301 and 400m (approximately 45%). Additionally, the accessibility from the forest road was the highest at "100m or less" for both OCB_ITPWD (24%) and FSB_ITPWD (31%), indicating that more trees were infected when a stand was closer to a forest road with higher accessibility. OCB_ITPWD hotspots were 31 and 32 compartments, and it was highly distributed in areas with a higher age class and a higher DBH class.

• Korean Institute of Interior Design Journal
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• v.20 no.1
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• pp.154-164
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• 2011

The purpose of this study is to identify more types of residents in medium-sized apartments in Seoul by lifestyle that has been used as a variable of space planning and to investigate and present bathroom design appropriate for characteristics of each resident type. The article examines the general characteristics, lifestyle types, and preference for the bathroom design. A total of 642 samples, acquired via internet survey, were analyzed with the statistical computer program SPSS PC+ window version 16.0. The conclusion of the article are as follows: 1) The lifestyle of users living in medium-sized apartments are categorized into 4 types: trend seeking, aesthetic seeking, family seeking, information seeking types. 2) The preference for the bathroom design of trend seeking type, the toilet is a bidet-builtin type and the washstand is a semi-counter type and the bathtub is a spa type and the shower booth is a bathtub-extending type. The storage closet is a upper-fixed type with two sides, the finishing materials are tiles and PVC monorium, and light built in a wall. 3) The preference for the bathroom design of aesthetic seeking type, the toilet is a bidet-builtin type and the washstand is a semi-counter type and the bathtub is a whirlpool type and the shower booth is a steam-sauna type. The storage closet is a upper-fixed with one side and opened closet, the finishing materials are tiles. 4) The preference for the bathroom design of family seeking type, the toilet is a bidet-builtin type and the washstand is a stand type and the bathtub is a reclamation type and the shower booth is a partition type. The storage closet is a upper-fixed with three sides. 5) The preference for the bathroom design of information seeking type, the toilet is a bidet-builtin type and the washstand is a semi-counter and the bathtub is a spa type and the shower booth is a partition type. The storage closet is a upper-fixed type with two sides. The results of this study may be used as basic data in planning bathroom design for housing supply for housing suppliers, and used as significant information for residents to identify their own types that can be referred when they select apartments to live in.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.3
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• pp.151-157
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• 2003

This research was conducted to investigate about structural characteristics of vegetation by change of the environmental factors for prolific open-pollinated progeny forest in Pinus koraiensis stands. Stand slope of Kapyung area was slower than Youngdong area. On the other hand, contents rate of the soil chemical properties in Kapyung was lower than Youngdong area. And relative intensity of light was higher Youngdong than Kapyung area. On the whole, growth of the Pinus koraiensis was more dominant Kapyung area than Youngdong. Analysis result of the relative density, - frequency, - coverage and importance value to shrub layer in each local stands, Quercus mongolica and Quercus acutissima were dominant species in Kapyung area. Dominant species In Youngdong area was Quercus acutissima. In Kapyung area, appearance species of the vegetation layer was consisted that live in moist soil and shaded lot. Youngdong area showed fewer species than Kpyung area. Species diversity of shrub and vegetation layer in Kapyung and Youngdong area was higher than Youngdong. This result was judged by slope difference between each areas. Kapyung area need enforce thinning and Youngdong area conduct tending management on shrub layer.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.193-204
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• 2018

This study was carried out to select the optimal method of competition index computation according to the competitor selection methods and distant-dependent competition index models, and to analyze the characteristics of competition indices in terms of thinning intensity and tree density targeting Pinus densiflora, Pinus koraiensis, and Larix kaempferi, which are the major coniferous species in Korea. Data was the re-investigated tree information from 240 permanent plots of 80 sites in the stands of P. densiflora, P. koraiensis, and L. kaempferi, which were located in the national forest of Gangwon and North Gyeongsang provinces. The number of subject trees with competition index calculated were 1126 trees for P. densiflora, 4093 trees for P. koraiensis, and 3399 trees for L. kaempferi. For the best competition index computation method, three kinds of competitor selection methods were considered: basal area factor, angle of height, angle of height to crown base. Also, six kinds of competition index models were compared: Lorimer, Martin-EK, Braathe, Heygi, Daniels, and Modified Daniels, which was developed in this study. Correlation coefficient was the best when the competitor selection method of basal area factor $4m^2/ha$ and the competition index model of Modified Daniels were used, and thus, it was selected as the best method for computing competition index. According to the best method by stand characteristics, competition index decreased in all species as thinning intensity was high and tree density was low.

• Korean Journal of Agricultural Science
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• v.33 no.2
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• pp.123-127
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• 2006

This study was carried out to compare growth and yield performance for soil conditions at the Maize Genetics and Breeding Lab. in Chungnam National University. The waxy hybrid corn in the drained soil of paddy field showed higher fresh yield per 10a and 100-kernel weight per plant than control. The average dry yield of drained and drainless soil were 804kg/10a and 498kg/10a compared with a control (751kg/10a), respectively. The waxy hybrid corn in the drained soil also had better good stand and stay green characteristics than drainless soil condition, and showed moderately resistance to water stress and weed. Vegetational feature of weeds was characterized as the prevalence of Acalypha auatralis, Echinochloa crus-galli, Persicaria hydrpopiper in drained paddy soil and Persicaria hydrpopiper, Acalypha auatralis, Echinochloa crus-galli in drainless paddy soil, and Echinochloa crus-galli, Acalypha auatralis in upland soil.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.509-515
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• 2017

Objectives: The purpose of this study was to assess the indoor levels of $PM_{10}$, VOCs and aldehydes in nail shop and hair salon. Methods: The field survey was conducted for 52 hair salons 52 nail shops, and 26 shop-in-shops in Seoul and Daegu city. The field technicians investigated characteristics of each shop including operating time, indoor volume, ventilation and so on. Indoor concentrations of $PM_{10}$, VOCs and aldehydes, indoor temperature and humidity were measured in 12 hair salons, 12 nail shops and 6 shop-in shops. MP Surveryor II (Graywolf, USA) was used to measure $CO_2$ concentration, temperature and humidity for 8 hours. $PM_{10}$ concentrations were measured by minivolume air sampler with Teflon quartz filter ($0.2{\mu}m$ pore size, ${\varphi}$ 47 mm, Graseby-Anderson TEF-DISKTM) for 6 hours. VOCs passive sampler (OVM 3500) was used to collect VOCs for 8 hours and analyzed by GC/MSD. Results: The $CO_2$ concentrations were $759.4{\pm}58.2$ ppm in nail shops, $731.0{\pm}72.5$ ppm in hair salons, and $656.4{\pm}31.2$ ppm in shop-in-shops. The $PM_{10}$ concentrations were $27.5{\pm}14.2{\mu}g/m^3$ in nail shops, $33.1{\pm}6.3{\mu}g/m^3$ in hair salons, and $39.0{\pm}26.9{\mu}g/m^3$ in shop-in-shops. TVOCs concentrations were $3085.4{\pm}1667.8{\mu}g/m^3$ in nail shops, $2131.1{\pm}617.3{\mu}g/m^3$ in hair salons, and $1550.3{\pm}529.0{\mu}g/m^3$ in shop-in-shops. TVOCs concentrations in nail shops were significantly higher than those in hair salons and shop-in-shops (p=0.002). Formaldehyde concentrations were $60.8{\pm}36.6{\mu}g/m^3$ in nail shops, $89.1{\pm}55.4{\mu}g/m^3$ in hair salons, and $45.1{\pm}22.5{\mu}g/m^3$ in shop-in-shops. Conclusion: TVOCs concentrations in nail shop were the highest among others. TVOC concentrations in all stores exceeded indoor air quality stand of indoor air quality control in public-use facilities, etc act.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.1
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• pp.37-48
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• 2007

Forest vegetation types and growth characteristics of Seongin-bong at Ulleung Island in Korea were studied by using importance values, distributions of diameter classes, and annual growth analysis. Vegetation types were classified into 7 groups. The number of existing woody plant and herbaceous plant species varied from 17 to 21 species per $100m^2$. In case of life-forms importance values, woody and herbs showed average values of 47% and 53% across 5 groups. But in Tsuga sieboldii-Pinus parviflora and Fague engleriana- Taxus cuspidata var. latifolia groups, woody importance values were 68% and 54%, respectively. Diameter classes in most stand types were regularly distributed and showed continuous growth in annual diameter growth. from these results, this site is expected to maintain a stable vegetation structure continuously. F. engleriana, which forms major species in this site, showed 0.46-0.62 cm in annual average diameter growth. The annual average diameter growth of broad-leaved tree species was 0.2-0.6 cm, while the growth rate of T. sieboldii and P. parviflora was 0.38 cm and that of T. cuspidata var, latifolia was below 0.1 cm.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.389-398
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• 2000

The work of visiting nursing personnel consists mostly of direct nursing and it is absolutely necessary that training of the nursing personnel for infection control be emphasized because most of patients are composed of elderly people with chronic diseases and malnutrition who are highly susceptible to infection. Accordingly. this study was designed to provide basic data for the development of an infection control program in public health centers as well as the promotion of perception and performance of infection control by analysing the perception of importance and performance in the infection control of visiting nursing personnel who carry out visiting nursing services. The subjects of this study consisted of a number of visiting nursing personnel working for 15 public health centers. 15 health-center branches. and 16 health clinics. The collection of data was grounded on a questionnaire method. The questionnaire breaks down to 8 questions about general characteristics and 108 questions in connection with the perception and performance of infection control. The results of this study are as follows: 1. 82 subjects (78.1%) responded that it is necessary to control infection. 79 subjects(75.3%) responded that education is necessary for infection control. 50 respondents (47.6%) answered in the affirmative in regard to the role of infection carriers. 2. The mean score for the perception of importance in infection control was 4.55 and that performance accounts for 4.03. this turns out to be very high. 3. In terms of the perception of importance per each field of infection control. medication. the management of contamination and sterilization, the control of environments and instruments. washing hands and individual hygiene as well as the prevention of cross-infection and the supervision of infection stand at 4.72. 4.64. 4.60. 4.58. 4.52 and 4.21 respectively. In terms of performance. the supervision of infection. the control of environments and instruments, individual hygiene and the prevention of cross infection. medication. washing hands, and the management of contamination and sterilization was 4.21. 4.12. 4.10. 4.03. 3.91 and 3.81 respectively. 4. In terms of the correlation between the perception of importance and the performance of infection control. the score stands high in all fields: this means the high perception of importance leads to high performance statistically (P< .05). 5. In terms of the perception of importance in general characteristics. there is no significant difference while the form of working places. working career and the career as visiting nursing personnel show a significant difference in terms of performance(P< .05). From the results. it is suggested that the visiting nursing personnel should be constantly educated with the aid of the development of infection control programs and that instructions and instruments for the management of infection should be worked out so as to enhance the performance of infection control on the part of nurses in applicable communities.