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A Study for Growth Density on the Pinus thunbergii and Pinus densiflora Communities in area of Busan, Korea (부산일대 곰솔림과 소나무림의 생육 밀도에 관한 연구)

  • Lee, Sang-Cheol;Hong, Suk-Hwan;Kim, Dong-Pil;Choi, Song-Hyun;Ahn, Mi-Yeon
    • Korean Journal of Environment and Ecology
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    • v.32 no.2
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    • pp.215-224
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    • 2018
  • The climate change is expected to weaken the habitat of Pinus densiflora and P. thunbergii, but they are still in high demand for planting. This study aims to suggest the rational community planting design based on natural forests' community structure in the southeastern region of Korea (warm temperate zone). For this study, we surveyed 22 plots of Pinus densiflora community and 60 plots of P. thunbergii community in Busan Metropolitan City which is located in the southeastern part of the Korean peninsula. We investigated the diameter of breath hight (DBH) and population of each tree layer in a $100m^2$ quadrat and used a regression analysis to derive a regression equation for estimating the mean number of planting individuals in each DBH. The coefficient between canopy layer's DBH and growth individuals per unit area ($100m^2$) was 0.700 for P. thunbergii communities and 0.533 for P. densiflora communities, indicating very high explanatory power by single factor. The predicted regression equation of between DBH and growth density was $Y=31.176e^{-0.055x}$ (X=DBH, Υ=growth individuals per $100m^2$) for P. thunbergii communities and $Y=38.351e^{-0.059x}$ for P. densiflora communities. Planting densities of P. densiflora communities and P. thunbergii communities in southeast region were higher than the central region.

Physico-Chemical Characteristics of Sediment in Sedimentation Tank of Infiltration Trench and Filtration System (비점오염저감시설인 침투도랑과 여과형 시설내 침강지 퇴적의 물리화학적 특성 분석)

  • Lee, Soyoung;Lee, Eun-Ju;Kim, Chulmin;Maniquiz, M.C.;Son, Youngkyu;Khim, Jeehyeong;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.9 no.3
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    • pp.35-42
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    • 2007
  • The paved areas such as parking lots and roads are stormwater intensive landuses since they are impervious and have high pollutant mass emissions from vehicular activity. Vehicle emissions include different pollutants such as heavy metals, oil and grease, particulates from sources such as fuels, brake pad wear and tire wear. Especially, the released heavy metals can be easily absorbed on the surface area of small particulate materials because of its ionic strength. Therefore, by constructing the sedimental tank in structural BMPs as a pre-treatment facility, the particles and heavy metals both can be removed from the runoff at an instant. To understand the physico-chemical characteristics of sediments from sedimentation tank, one-year study at an infiltration trench and filtration system was conducted to quantify the metal mass absorbed on sediments with various particle sizes. The structural BMPs for this study are located in Yongin City, Kyunggido. The research results show that Cu, Zn and Pb are dominant metal compounds in the sediments. Also the metal concentrations are highest at the ranges of $425-850{\mu}m$ particle sizes. The results will provide the basic physico-chemical information of sediments to treat it as solid wastes and to determine the design criteria of sedimentation tank in structural BMPs.

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A Study on the Drying and Carbonization of Sewage Sludge in Fluidized Bed Reactor (유동층 반응기에서 하수슬러지의 건조 및 탄화 특성에 관한 연구)

  • Choung, Young-Hean;Cho, Ki-Chul;Kang, Dong-Hyo;Kim, Yi-Kwang;Park, Chang-Woong;Oh, Kwang-Joong
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.7
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    • pp.746-751
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    • 2006
  • In this study, drying and carbonization experiment was conducted in a fluidized bed reactor according to the variations in gas velocity, particle size, and reactor temperature. As a result, the weight loss rates of sludge by drying in the fixed bed and fluidized bed type dryer showed that drying in the fluidized bed was about 6 times faster than drying in the fixed bed, and the weight loss rates of sludge by carbonization in the fixed bed and fluidized bed type reactor showed that carbonization in the fluidized bed was about 4 times faster than drying in the fixed bed. This implies that carbonization in the fluidized bed was completed within 10 minutes. Although the amount of char decreased with the increase of carboniration temperature, the amount of char became similar at upper 873K. Also, the amount of char decreased with increasing gas velocity. Consequently, it could be efficient that slow fluidization should be maintained within the range of fluidization in case of fluidized carbonization of sewage sludge at 873K.

New Record for Alien Plant of Diplachne fusca subsp. uninervia and a Taxonomic Identification of D. fusca subsp. fascicularis in Korea (한반도 미기록 외래식물 좀갯드렁새와 갯드렁새의 분류학적 실체)

  • Kim, Jung-Hyun;Kim, Jin-Seok;Sim, Sunhee;Lee, Wunggi;Park, Sung-Ae
    • Korean Journal of Plant Resources
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    • v.33 no.2
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    • pp.130-137
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    • 2020
  • We found Diplachne fusca subsp. uninervia (J. Presl) P.M. Peterson & N. Snow, an unrecorded alien plant, in Gimpo-si, Gyeonggi-do and Ganghwa-gun, Incheon Metropolitan City. Diplachne fusca subsp. uninervia is native to North America (the USA and Mexico), Central America (Belize, Costa Rica, Honduras, and Nicaragua), the Caribbean (the Bahamas, Cuba, Jamaica, and Puerto Rico), and South America (Venezuela, Brazil, Bolivia, Ecuador, Peru, Argentina, Chile, Paraguay, and Uruguay). It is reported as an invasive species worldwide. Diplachne fusca subsp. uninervia is closely related to D. fusca subsp. fascicularis (Lam.) P.M. Peterson & N. Snow (Gaet-deu-reong-sae in Korean), an invasive species in Korea, and both are infraspecific taxa of the species D. fusca. Diplachne fusca subsp. uninervia is distinguished from D. fusca subsp. fascicularis by the small size of its spikelets, glumes, and lemmas, with apex awnless. Its common name is "Jom-gaet-deu-reong-sae" based on the short spikelets. We found that D. fusca (≡Leptochloa fusca), previously known as "Gaet-deu-reong-sae", was misapplied. It is morphologically different from D. fusca subsp. fascicularis. Therefore, we changed the scientific name of Gaet-deu-reong-sae from D. fusca (≡L. fusca) to D. fusca subsp. fascicularis based on the type specimens, original descriptions, and recent studies.

A National Study Explaining the Public Library Use among Korean Adults: Examining the Influence of Individual Characteristics, Local Library Inputs, and Local Government Investments (한국 성인의 공공도서관 이용에 영향을 미치는 주요 요인 분석 - 개인, 도서관의 특성 및 자치단체의 도서관 투자를 중심으로 -)

  • Kwon, Nahyun;Song, Kyeong-Jin
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.4
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    • pp.291-312
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    • 2014
  • The purpose of this national study is to identify the factors affecting the public library use among the Korean adult population. The study constructed a model of three types of factors to explain the frequency of public library visits: an individual's socio-demographic characteristics, input and output measures of the local library, and the community size and library investment of the local government. The data were collected from both a national representative sample of 1,000 adults of 18 years old or above who participated in a web survey and the 2013 National Library Statistics of Korea. It was found that a more frequent public library visit occurred when a person who read more and lived closer to the library, which was newly established in a small to medium-sized scale, who lives in a city with a greater population and with more library staff members serving a fewer patrons. Implications for future public library constructions and for public services were suggested based on the study findings.

Effects of Oral Health Education Program on the Oral Health Knowledge, Oral Health Behavior and Oral Hygiene Status of Elementary School Students (구강보건교육 프로그램이 초등학생의 구강보건지식, 구강보건행위 및 구강위생 상태에 미치는 효과)

  • Son, Mi-Hyang
    • Research in Community and Public Health Nursing
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    • v.14 no.1
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    • pp.24-35
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    • 2003
  • The purpose of this study was to evaluate the effects of oral health education program on the oral health knowledge, oral health behavior and oral hygiene status of elementary school students. The design of this study is nonequivalent control group pretest-posttest gesign. Data was collected between the 17th of June and 13th of July in 2002, and the Experimental group were 131 students of Y Elementary School. which was one of the two elementary schools in K City, Gyeongsangbuk-do, and the control group was 140 students of C Elementary School, which was similar to Y Elementary School in geographical and economical properties and size. As for research tools, the researcher developed tools of measuring oral health knowledge and oral health behavior by modifying the tools developed by Hye-Kyong Kim (2001), In-hyang Seo (1988), Ho-Youn Lee (2001), Hyeon-ja Jeon (1998). To measure oral hygiene status. the researcher applied a coloring agent to the surface of the teeth after brushing, rinsed the mouth, and calculated colored plaque on the surface of the teeth, which was recorded on a sheet and analyzed using the plaque index. The data analysis was done using frequency, percentage, mean, standard deviation, Chisquare test, t-test, ANCOVA, Two-way ANOVA, Simple main effects, One-way ANOVA, and Duncan. Using with SPSS WIN 10.0. The result of this study are summarized as follows: 1. The hypothesis was supported 'The elementary school students which was given oral health education program will shows higher oral health knowledge, oral health behavior, oral hygiene status then control group' 2. According to the result of verifying the hypothesis, 'The effect of oral health education program will be different between junior and senior' the hypothesis was partly supported To summarize result of this research, the experimental group, to which oral health education was given, was improved in oral health knowledge, oral health behavior and oral hygiene status compared to the control group, so the oral health education program was effective for the oral health of elementary school students.

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The Behaviour of Dust Concentrations During Sand Storm in Seoul Area (황사기간 중 PM2.5, PM10, TSP 농도 특성에 관한 연구)

  • Kim, Min-Young;Kim, Kwang-Rae;Lee, Min-Hwan;Cho, Seog-Ju
    • Journal of the Korean earth science society
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    • v.24 no.4
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    • pp.315-324
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    • 2003
  • The characteristics of particles were evaluated through the measurement data of PM$_{2.5}$, PM$_{10}$ and TSP instruments located in air quality monitoring stations installed and operated by Seoul Metropolitan city. The data of particulate mass on the filter was collected bv a high volume air sampler during the sand storm period. The number of days of sand storm in Seoul showed a different pattern from 1990 to November 2002, We can see a trend of increased occurrence and duration of sand storms. The ratio of PM$_{10}$ to TSP was shown as 52.9% and 59.4% during the sand storm period in 2000 and 2001. respectively. It was indicated that the particles larger than 10${\mu}$m increased by approximately 10% in sand storm periods compared to no sand storm period. While PM$_{10}$ size fraction reached 71.4% in 2002, the contribution of sand storm to total particulate concentration was estimated to be 11.9% for PM$_{2.5}$, 23.1% for PM$_{10}$, 19% for TSP in 2002, respectively and sand storms highly correlated with annual total particulate concentration.

A Study on managing Electric Application in Family-Mainly Refrigerator- (가정의 전기기기 관리에 관한 연구)

  • 문숙재;이재희
    • Journal of Families and Better Life
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    • v.1 no.2
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    • pp.43-57
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    • 1983
  • The purpose of the study, was to investigate Housewives behavior on how to buy refrigerators and how to use them. Besides, their knowledge and keeping ability of electricity and refrigerator is estimated according to regional differences, their ages, their educational courses, and their income. In the report, W e can see if it is related to the years of married life, numbers of the family, having jobs or not, and numbers of marketing a week. The subjects were 675 mothers of the students in the selected schools, at Seoul, Cheongjoo, and Kwesan gun. They answered to the questionnaire devised for the study. their answers were analyzed in percent to grasp their general trend of electricity and electric Appliance. Chi-square test and F-test are chosen to grasp the Cor-relationships between the related variables. The results are as follows: 1) The average rate of possesing the refrigerators is 84.06%. It shows us that the housewives in Seoul possess the more refrigerators than those in other areas. At ages, form 30 to 40 aged women gave the most refrigerators than any other ages women. It reveals us the high income and high educational housewives have high rate of possessing refrigerators. 2) They answered that they purchased the refrigerators by necessity. we can see their motivation of purchasing them is very reasonable. However, we can see that they do not manage the refrigerators well, because the rate of using them during four seasons is only 12.34%, An age of 20year old housewives mostly purchased the refrigerators at the time of marriage. The women who bought them after marriage answered that they mostly took a consultation with their husbands when they bought the refrigerators. They regarded the trade marks of the manufactures and size of the refrigerators, as they bought them. And most of them bought the refrigerators for cash. 3)At homes in Seoul, the kinds of retained foods in the refrigerator are more than those of the house in the city and in the agricultural town. The high income and high educational housewives tend to retain the more kinds of foods. But there are no significant differences between the essential variables such as the numbers of the family, the housewives having jobs or not, and the numbers of marketing. 4)Generally their knowledge on electricity and the refrigerator is very low. However, it shows the statistically significant differences. the housewives in Seoul have more information about refrigerator than the housewives in agricultural town. At ages , the women less than 29 years old have more information about the refrigerator, and the woman who had university education and high income tend to know much about the refrigerator. 5) The keeping ability of the refrigerator is very good, and there are no significant differences among variables. And also it shows that there is no correlationship between their knowledge and their keeping ability.

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The Effect of Coffee Shop Selection Attributes on Revisit Intention: Focused on Mediating Effect of Brand Trust (커피 전문점 선택속성이 재방문의도에 미치는 영향: 브랜드 신뢰의 조절효과)

  • Jung, Ja Young
    • Journal of Digital Convergence
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    • v.11 no.11
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    • pp.289-304
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    • 2013
  • In Korea the consumption of coffee has been continuously increased last 10 years. During the period the market size and the numbers of the coffee shop also has been expanded dramatically. The purpose of this study was to examine whether the consumer's selection attributes of coffee shop affect the revisit intention of coffee shop and the brand trust had moderating effects between consumption attributes and revisit intention. Also it was analyzed whether there were statistic differences according to the demographic characteristics. For this study the survey was conducted on Seoul City and Kyeongki-do province and 600 questionnaires were distributed and 480 were collected and 470 samples were analyzed. The results of this study were as follows. All the factors of the consumer's consumption attributes of coffee shop had affected the revisit intention. And the factors of brand trust had moderating effects on revisit intention. There were statistic difference by gender for the additional services and there were also statistic difference according to the age group for the new technology environmental service of the inside of coffee shop. The implications of this study were the selection attributes of coffee shop were diverse and the brand trust were considered significant and the consumer's preferences were different according demographic characteristics such as gender, age, and incomes.

A Study on the Correlation between Plant Community and Environmental Factors of Tongdosa(Temple) Area, Gajisan(Mt.) Provincial Park (가지산도립공원 통도사지구의 식물군락과 환경요인의 상관관계)

  • Lee, Sang-Cheol;Kang, Hyun-Mi;Kim, Ji-Suk;Yu, Chan-Yeol;Choi, Song-Hyun
    • Korean Journal of Environment and Ecology
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    • v.28 no.6
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    • pp.715-724
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    • 2014
  • Tongdosa, which is located in Gajisan(Mt.) Provincial Park of Yangsan City, is one of three representative temple in Korea. The purpose of this study was to investigate a relation between plants community and environmental factors in Tongdosa(Temple) District of Gajisan(Mt.) Provincial Park. In order to find out vegetation structure of Gajisan(Mt.) Provincial Park, thirty one plots(unit size: $200{\sim}300m^2$) were set up and surveyed. For environmental factors, it were surveyed and analyzed physical factors such as altitude, aspect etc. and soil characteristics such pH, organic content, total nitrogen content, exchangeable cation and so on. Using DCCA technique, a relation between plants community and environmental factors were analyzed. The surveyed plots were divided into five groups which are Pinus densiflora - Quercus aliena, Carpinus tschonoskii - Q. spp., P. densiflora - C. tschonoskii, P. densiflora - Q. variabilis, and Q. variabilis - Q. mongolica community. Vegetation succession was progressed from Pinus densiflora toward Carpinus tschonoskii and Quercus spp. It was found out that the distribution of vegetation was affected by altitude. Pinus densiflora - Quercus aliena community is located lower altitude and Q. variabilis - Q. mongolica community is located higher area.