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A Study on the Distribution and Correlation of Population, Industrial Employees and Highest Land Value of Seoul (서울시의 인구, 산업별 종사자 및 최고지가의 분포와 상관관계에 대한 연구)

  • Shin, Yeong-Jae
    • Journal of the Korean Geographical Society
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    • v.49 no.4
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    • pp.509-524
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    • 2014
  • The purpose of this study is to research on the distribution and correlation of population, industrial employees and highest land value of Seoul. The followings are result of the study. First, the population of Seoul City in 2012 decreased by 0.3%, compared with that in 1996. While the population of Gangbuk decreased, that of Gangnam increased. Second, the number of industrial employees showed larger gap than population, and it showed larger regional gap on producer service. Third, Jung-gu in Gangbuk had the highest land value among commercial areas of Seoul, but there was no significant gap between Gangbuk(Jung-gu and Jongro-gu) and Gangnam(Seocho-gu and Gangnam-gu). Fourth, in the average of the highest land value of residential area of Seoul City, Gangnam was more expensive, because of facilities and living conditions of Gangbuk and Gangnam is big difference. Fifth, the regional gap of the highest land value and the lowest land value of Seoul City is commercial areas larger than residential area. Finally, there was no correlation between the distribution of population and land value, between the increase of population and that of land value, but there was positive correlation between the distribution of industrial employees and the highest land value of commercial area and residential area of Seoul City.

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Optimum Monitoring Parameters for the Safety of Mechanical Seals (미캐니컬 씰의 안전운용 감시를 위한 최적 계측인자)

  • Soon-Jae Lim;Man-Yong Choi
    • Journal of the Korean Society of Safety
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    • v.12 no.4
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    • pp.214-219
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    • 1997
  • The mechanical seals, which are installed in rotating machines like pump and compressor, are generally used as sealing devices in the many fields of industries. The failure of mechanical seals such as leakage, crack, breakage, fast and severe wear, excessive torque, and squeaking results in big problems. To identify abnormal phenomena on mechanical seals and to propose the proper monitoring parameter for the failure of mechanical seals, sliding wear experiments were conducted. Acoustic emission, torque, and temperature were measured during experiments. Optical microstructure was observed for the wear processing after every 10 minute sliding at rotation speed of 1750 rpm and scanning electron microscopy was also observed. Except for the initial part of every experiment, the variation of acoustic emission was well coincided with torque variation during the experiments. This study concludes that acoustic emission and torque are proper monitoring parameters for the failure of mechanical seals. The intensity of acoustic emission signals is measured in root mean square voltage. Temperature of sealing face will be used as a parallel parameter for increasing the reliability of monitoring system.

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Characteristics of Tropical Cyclones over the Western North Pacific in 2008 (2008년 태풍 특징)

  • Cha, Eun-Jeong;Hwang, Ho-Seong;Yang, Kyung-Jo;Won, Seong-Hee;Ko, Seong-Won;Kim, Dong-Ho;Kwon, H. Joe
    • Atmosphere
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    • v.19 no.2
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    • pp.183-198
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    • 2009
  • The purpose of this study is to summarize the tropical cyclone (TC) activity of 2008 over the western North Pacific including the verification of the official track and intensity forecast errors of these TCs. The TC activity - frequency, Normalized Typhoon Activity (NTA), and life span - was lower than 58-year (1951-2008) average. 22 tropical cyclones of tropical storm (TS) intensity or higher formed in the western North Pacific and the South China Sea in 2008. The total number is less than 58-year average frequency of 26.4. Out of 22 tropical cyclones, 11 TCs reached typhoon (TY) intensity, while the rest 11 TCs only reached severe tropical storm (STS) and tropical storm (TS) intensity - six STS and five TS storms. One typhoon KALMAEGI (0807) among them affected the Korea peninsula. However, no significant impact - casualty or property damage - was reported. On average of 22 TCs in 2008, the Korea Meteorological Administration (KMA) official track forecast error for 48 hours was 229 km. There was a big challenge for individual cyclones such as 0806 FENGSHEN and 0817 HIGOS presenting significant forecast error, with both intricate tracks and irregular moving speed. The tropical cyclone season in 2008 began in April with the formation of NEOGURI (0801). In May, four TCs formed in the western North Pacific in response to enhanced convective activity. On the other hand, the TC activity was very weak from June to August. It is found that the unusual anti-cyclonic circulation in the lower level and weak convection near the Philippines are dominant during summertime. The convection and atmospheric circulation in the western North Pacific contributed unfavorable condition for TC activity in the 2008 summertime. The 2008 TC activity has continued the below normal state since mid 1990s which is apparent the decadal variability in TC activity.

Discussions on Carbon Account in Harvested Wood Products and Effects on Korean Carbon Emissions under the UNFCCC (기후변화협약 하에서 목제품 탄소계정 논의 동향 및 국내 탄소배출량에 미치는 영향 분석)

  • Choi, Soo Im;Bae, Jae Soo;Jung, Byung Heon
    • Journal of Korean Society of Forest Science
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    • v.95 no.4
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    • pp.405-414
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    • 2006
  • Korea is expected to be included in the countries of compulsory reduction of greenhouse gas emissions from the 2nd commitment period (2013~2017). For the negotiations in the future, this study was designed to review the tendency of discussions about carbon account in harvested wood products (HWP), which is currently underway around the globe and approach-specific characteristics, and analyze effects on carbon emissions in our country. As a result, most importantly, except the current IPC default approach there is no big difference among the 3 approaches of carbon account in HWP, which were newly suggested on the basis importers because all the HWP circulated at home are accounted for by carbon-stock changes. Under production approach, those HWP produced at home only are evaluated according to carbon-stock changes with the exception of imported HWP. Atmospheric-flow approach is favorable to net wood exporters, because the spot where ultimate decomposition and combustion arising out of the use of HWP occur is regarded as the place of carbon emission. Meanwhile, the estimation of korean carbon-stock change in HWP showed that as of 2004, stock-change approach was 1.567 Tg C, with production approach being 0.581 Tg C and atmospheric-flow approach being -1.425 Tg C, which means stock-change approach is most favorable to Korea as a net wood importer, while atmospheric-flow approach is the least favorable one, in terms of carbon emissions reduction in Korea.

Mass Loss and Nutrients Dynamics During the Litter Decomposition in Kwangnung Experimental Forest (광릉(光陵) 시험림(試驗林) 내(內)의 임분별(林分別) 낙엽(落葉)의 분해(分解)와 분해과정(分解過程)에 따른 영양염류(營養鹽類)의 변화(變化))

  • You, Young-Han;Namgung, Jeong;Lee, Yun-Young;Kim, Jeong-Hee;Lee, Jong-Young;Mun, Hyeong-Tae
    • Journal of Korean Society of Forest Science
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    • v.89 no.1
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    • pp.41-48
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    • 2000
  • Mass loss and dynamics of mineral nutrient during decomposition of deciduous leaves and 3 species of needles were investigated for 38 months from October in 1992 to November in 1995 in Kwangneung, Korea. After 38 months, the remaining mass of deciduous leaves, Pinus koraiensis, Pinus rigida and Abies holophylla was 16.2%, 29.8%, 33.5% and 53.9%, respectively. The decay rate (k) of deciduous leaves, Pinus koraiensis, Pinus rigida and Abies holophylla was 0.61, 0.40, 0.37, $0.21yr^{-1}$, respectively. The lowest decay rate in fir needle might be, in part, due to low N concentration. N concentration of the decomposing litter increased during the experimental period except for P. rigida. Deciduous leaves showed a short immobilization period during the early stage of decomposition, and big-cone pine and pitch pine had no immobilization period. However, there was no net N mineralization in fir litter. P increased during the experimental period for all litter. Except for deciduous leaves, there was no net mineralization period. In case of deciduous leaves, however, remaining P after 38 months was 53% of the initial P capital. Remaining cations of the decomposing litter after 38 months were lower than those of initial contents.

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Analyzation and Improvements of the Revised 2015 Education Curriculum for Information Science of Highschool: Focusing on Information Ethics and Multimedia (고등학교 정보과학의 2015 개정 교육과정에 대한 분석 및 개선 방안: 정보윤리와 멀티미디어를 중심으로)

  • Jeong, Seungdo;Cho, Jungwon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.208-214
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    • 2016
  • With the rising interest in intelligence information technology built on artificial intelligence and big data technologies, all countries in the world including advanced countries such as the United States, the United Kingdom, Japan and so on, have launched national investment programs in preparation for the fourth industrial revolution centered on the software industry. Our country belatedly recognized the importance of software and initiated the 2015 revised educational curriculum for elementary and secondary informatics subjects. This paper thoroughly analyzes the new educational curriculum for information science in high schools and, then, suggests improvements in the areas of information ethics and multimedia. The analysis of the information science curriculum is applied to over twenty science high schools and schools for gifted children, which are expected to play a leading role in scientific research in our country. In the future artificial intelligence era, in which our dependence on information technology will be further increased, information ethics education for talented students who will play the leading role in making and utilizing artificial intelligence systems should be strongly emphasized, and the focus of their education should be different from that of the existing system. Also, it is necessary that multimedia education centered on digital principles and compression techniques for images, sound, videos, etc., which are commonly used in real life, should be included in the 2015 revised educational curriculum. In this way, the goal of the 2015 revised educational curriculum can be achieved, which is to encourage innovation and the efficient resolution of problems in real life and diverse academic fields based on the fundamental concepts, principles and technology of computer science.

The Effects of Emotional Labor on Casino Dealers' Burnout and Depression (감정노동이 카지노 딜러의 소진과 우울에 미치는 영향)

  • Kim, Hye-Ja;Kang, Jong-Soo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.12
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    • pp.276-285
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    • 2017
  • The purpose of this study was to verify the effects of emotional labor on casino dealers' burnout and depression. Burnout is a big problem which thwarts their professionalism and effectualness and the effectiveness of the service they provide. Depression is a core factor which affects one's mental health. To analyze the effects of emotional labor on casino workers' burnout and depression, we conducted a survey of 606 casino dealers of H resort and analyzed the results. Burnout was measured in terms of the client-related burnout and work-related burnout by the Copenhagen Burnout Inventory (CBI), and depression was measured by the Beck Depression Inventory (BDI). The research findings are as follows. First, the level of emotional labor (3.50) was higher than the mid-point on the 4 point Likert scale, and the work-related burnout (3.86) and client-related burnout (3.91) were higher than the mid-point on the 5 point Likert scale. Second, emotional labor was correlated to their depression and burnout. Third, emotional labor showed a significant difference according to gender, while burnout showed significant differences according to age, position and term of service. Fourth, emotional labor had an effect on the casino dealers' burnout and depression. We discussed the implications of these findings and possible strategies to alleviate this situation, for example, the passing of a law and development of an employee assistance program (EAP) to prevent their burnout and reduce their depression.

Distribution of Phytoplankton Biomass and Nutrient Concentrations in the Barents and Kara Seas during the 1st Korea-Russia Arctic Expedition in August, 2000 (제 1차 한-러 북극해 탐사(2000년 8월) 동안의 바렌츠해와 카라해의 식물플랑크톤 현존량 및 영양염 분포)

  • Kang, Sung-Ho;Chung, Kyung-Ho;Kang, Jae-Shin;Kim, Yea-Dong
    • Ocean and Polar Research
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    • v.25 no.3
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    • pp.315-329
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    • 2003
  • During the 1st Korea-Russia Arctic Expedition from 3 to 26 August, 2000 phytoplankton biomass and nutrient concentration were measured in the Barents and Kara Seas. Total of 57 surface samples were collected f3r the phytoplankton related measurements. Chlorophyll a (chi a) concentraitons were measured to investigate the relations between physico-chemical factors and phytoplankton biomass distribution. Chl a values ranged from 0.14 to $2.34mg\;m^{-3}$ (mean of $0.65{\pm}0.42mg\;m^{-3}$) over the surface stations. The elevated values of the chi a concentrations $(1.49{\sim}2.34mg\;m^{-3})$ were found in the southeastern Barents Sea near the Pechora River. Nanoplanktonic $(<20{\mu}m)$ phytoflagellates were the important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 80% of the total chi a biomass in the study area. Mean chi a concentration in the Barents Sea $(0.72{\pm}0.57 mg\;m^{-3})$ was higher than in the Kan Sea $(0.52{\pm}0.45mg\;m^{-3})$, but there was no big difference between two areas. Surface temperatures and salinities ranged from 4.1 to $11.7^{\circ}C$ (mean of $8.8{\pm}1.9^{\circ}C$) and from 23.8 to 32.5psu (mean of $30.3{\pm}1.9^{\circ}C$ psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. It is speculated that the insignificant correlation between phytoplankton biomass and physical factor was due to the same current which introduced similar water mass with higher water temperature and lower salinity into the study area. The mean values of major nutrients such as ammonia, nitrite, nitrate, phosphate, and silicate were $0.42{\pm}0.31{\mu}M,\;0.10{\pm}0.03{\mu}M,\;1.44{\pm}1.03{\mu}M,\;0.35{\pm}0.12{\mu}M,\;10.99{\pm}3.45{\pm}M$, respectively. The relations between phytoplankton biomass and nutrient concentration were not close, indicating that the surface nutrient concentrations during the study seem to be controlled by other physical factors such as input of fresh water (i.e. dilution effects).

A Study on the Constructivist Multimedia-Assisted Instruction in Secondary School Geography (중등 지리과에서의 구성주의적 멀티미디어 활용 수업의 모형 개발과 효과 분석)

  • Bae, Sang-Woon;Jo, Wha-Ryong
    • Journal of the Korean association of regional geographers
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    • v.5 no.1
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    • pp.163-185
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    • 1999
  • The purpose of this study is to develop the model of constructivist multimedia-assisted instruction(CMAI) and to analyze the effect of it in the secondary school geography. The main results are as follows : (1) The conceptual model of CMAI can be defined as an instruction aiming at making a person who has self-directed learning ability through constructivism and multimedia. The procedural model of CMAI based on PIDA instructional strategy is divided into four stages : prediction & explanation, inquiry activity, discussion & fixation, application & synthesis stage. (2) CMAI is typed by offline CMAI and online CMAI. that is, O/WCMAI(online CMAI by web-based courseware). Offline CMAI is subdivided into P/TCMAI(offline CMAI by presentation-based courseware) and C/RCMAI(offline CMAI by cd-rom based courseware) according to authoring tool and function. (3) Offline constructivist multimedia course-ware(offline courseware) was developed for 2 periods as the material to analyze the effect of CMAI. Offline courseware is received development level of it. (4) After offline courseware being applied to the class, the effect of it according the types of the CMAI instruction(lecture instruction, whole teaching, individualized learning, cooperative learning) was analyzed. As the result of analyzing the descriptive statistics of the level of learning achievement and instruction response, there isn't big relationship between them. As the result of analyzing the inferential statistics of the level of learning achievement, there wasn't significant difference between the types of CMAI instruction in whole student of the classes and certain students who improved their grades. But as the result of analyzing of the level of instruction response, there was significant difference between lecture instruction and other types of the CMAI instruction(whole teaching, individualized learning, cooperative learning).

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A Survey on Preferences for Vegetable Cooking Methods and Vegetable-aversion-related Factors among Elementary School Students in Kwangju and Chonnam Regions (광주.전남지역 초등학생의 채소기피 관련요인 및 채소류의 조리법에 대한 기호도 조사)

  • Ahn, Yu-Kyong;Ro, Hee-Kyong
    • Korean Journal of Community Nutrition
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    • v.14 no.5
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    • pp.531-544
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    • 2009
  • This study was conducted to survey multiple factors of aversion to vegetables and preferences for vegetable-related recipes in school meal services among elementary school children in order to help develop various menus and recipes for school meal services. Questionnaire survey was carried out with the study subjects, who were 401 children in 6th grade attending elementary schools in Chonnam and Kwangju metropolitan regions. Results from the survey can be summarized as follows: 65.1% of respondents answered they try to eat vegetables and other namul side dishes served in school meal service for health. As for the frequency of taking vegetables and namul side dishes out of daily meals, 47.4% of respondents chose 'once or twice'. The reasons for aversion to vegetables in boys were taste and cooking method, while girls were taste and feeling between teeth. In boys there were no differences between regions of Kwangju and Chonnam but the tendency of aversion to vegetables was significantly high in girls. As for the aspects of vegetable aversion of subjects, 46.9% of respondents took up 'black & purple' in the unfavorable color of vegetables. 49.1% in 'bitterness' and 39.2% in 'greasiness' were in terms of the aversive taste of vegetables. The aversive vegetable recipes were 58.6% in 'raw & seasoned' and the unfavorable feeling of vegetables were 53.1% in 'squashiness'. There were differences between regions of Kwangju and Chonnam with boys in color and cooking method in girls. Results from the survey on their preferences for vegetable recipes showed that leafy vegetables like crown daisy (raw/slightly seasoned) and pak choi (broth/pot stew) fell to the most aversive category, while bean sprouts (broth/pot stew) were chosen as the most favorable one. Among root vegetables bell-flowers were found to belong to the least preferred recipe, while potatoes were proven to be most preferable in terms of recipes. As for fruit vegetables and other vegetables, all respondents didn't like 'fatsia shoots' vegetable and it's cooking method and they preferred 'green pumpkins (broth/pot stew)'. In respect of mushrooms, enoki mushroom (broth/pot stew) was found most preferred and had high tendency of preferences in boys and girls in Kwangju compared with Chonnam region. The study results indicated that respondents did not show big differences in factors influencing them to be averse to vegetables and their preferences for vegetable recipes depending on regions. In order to have high preference and intake in children's diets, it needs to study in reform of menu about using namul or vegetables mixed with meats and fruits that children preferred or applying roasted and fried other less than namul.