• Title/Summary/Keyword: Model building

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A Study for the Methodology of Analyzing the Operation Behavior of Thermal Energy Grids with Connecting Operation (열 에너지 그리드 연계운전의 운전 거동 특성 분석을 위한 방법론에 관한 연구)

  • Im, Yong Hoon;Lee, Jae Yong;Chung, Mo
    • KIPS Transactions on Computer and Communication Systems
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    • v.1 no.3
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    • pp.143-150
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    • 2012
  • A simulation methodology and corresponding program based on it is to be discussed for analyzing the effects of the networking operation of existing DHC system in connection with CHP system on-site. The practical simulation for arbitrary areas with various building compositions is carried out for the analysis of operational features in both systems, and the various aspects of thermal energy grids with connecting operation are highlighted through the detailed assessment of predicted results. The intrinsic operational features of CHP prime movers, gas engine, gas turbine etc., are effectively implemented by realizing the performance data, i.e. actual operation efficiency in the full and part loads range. For the sake of simplicity, a simple mathematical correlation model is proposed for simulating various aspects of change effectively on the existing DHC system side due to the connecting operation, instead of performing cycle simulations separately. The empirical correlations are developed using the hourly based annual operation data for a branch of the Korean District Heating Corporation (KDHC) and are implicit in relation between main operation parameters such as fuel consumption by use, heat and power production. In the simulation, a variety of system configurations are able to be considered according to any combination of the probable CHP prime-movers, absorption or turbo type cooling chillers of every kind and capacity. From the analysis of the thermal network operation simulations, it is found that the newly proposed methodology of mathematical correlation for modelling of the existing DHC system functions effectively in reflecting the operational variations due to thermal energy grids with connecting operation. The effects of intrinsic features of CHP prime-movers, e.g. the different ratio of heat and power production, various combinations of different types of chillers (i.e. absorption and turbo types) on the overall system operation are discussed in detail with the consideration of operation schemes and corresponding simulation algorithms.

Evaluation on the radiation exposure from activated wedge filter (10MV 이상 고에너지 사용시 wedge filler의 방사화가 작업환경에 미치는 영향평가)

  • Lee HwaJung;Kim DaeYoung;Kim WonTaek;Lee KangHyeok
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.69-79
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    • 2004
  • In the process of photon treatments, linear accelerators with energies higher than 10 MV produce neutrons through the (${\gamma}$, n) interactions with the composite materials of the linac head md these materials further produce the induced radiations. We investigate the possible risks from these induced radiations especially in the wedge filters to the radiation workers. Wedge filters are used to modify the isodose profiles in the radiation treatment using the linear accelerator and always be handled by the radiation workers. For the background radiation, we measured the radiation in both the waiting room and the outside of the building for two hospitals, S and H. The results of S hospital were $0.11\;{\mu}Sv/hr$ and $0.10\;{\mu}Sv/hr$ for waiting room and outside respectively, and in the case of H hospital, they were $0.12\;{\mu}Sv/hr$ and $0.11\;{\mu}Sv/hr$. Using a survey meter, we measured the radiation from wedge filters inserted in 10 MV and 15 MV Siemens linear accelerators. The time series measurements were done in ${\sim}1$ minutes after exposure of 5 Gy of monitor units for the field size of $25{\times}25cm^2$. The starting value of 10 MV machine was about $3.26\;{\mu}Sv/hr$, which was three times higher than that of 10 MV. The measured radiation was from $^{28}Al$ and $^{53}Fe$ with a half life of 3.5 min. If the treatment patients are $20{\sim}50$ per day and the number of process of wedge filter change per patient is one or two, the annual dose equivalent is $0.08{\sim}0.4\;mSv$ for 10 MV, and $0.27{\sim}1.36\;mSv$ for 15 MV, which are in the range of dose equivalent limits of radiation workers.

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A Inquiry of the Perception of Death in School Age (학령기 아동의 죽음인식에 관한 탐색적 연구)

  • Joun, Young-Ran
    • Korean Journal of Hospice Care
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    • v.8 no.1
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    • pp.13-28
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    • 2008
  • Purpose: This paper aims to examine the subjective structures and types of school age children's perception of death through an investigative study on their perception of death in order to provide a basic material for them to understand death, and develop and carry out an effective death education program. Methods: The study method used the Q Methodology which can investigate the subjective structures and types of school age children's perception of death. For Q-population, 20 school age children were used as subjects for neutral interviews and open surveys, and through documentary research, a total of 132 statements were collected, For Q-samples, 23 statements (Q-samples) were derived through a non-structural method. P-samples were 31 school age children (8-13 year olds), Q-sorting was carried out using Q-cards, and the collected data was analyzed using the PC QUANL program. Results: As a result of the study, children's perception of death was divided into five types. The first type was functional type, characterized by prominent subjective perception regarding the elements of death, such as non-reversibility, universality, non-functionality, and causality. The second was after-life type, characterized by a strong, focus on life after death in one's perception of death, and it included children with Christian background and those who had experienced death in their immediate family. The third was religious type, characterized by a strong belief in being able to still watch over one's family and friends after one's death, resulting in a positive faith in the after-life. The fourth was fearful type, characterized by a deeper fear of death in comparison to other types. The fifth was realistic type, characterized by a strong and positive assent to the perception of good death. Conclusion: The significance of the results of this paper's study to Nursing is as follows. In terms of understanding the subjectivity of school age children's perception of death in nursing practice, and understanding the compositional elements of death presented with strong emphasis in existing literature and studies, the results will expand these understandings and allow us to understand the level of perception in school age children regarding the definition of death, after-life, and good death, be utilized as useful material in developing an effective death education program for them according to their type characteristics, and become the fertilizer for enabling the children to live a proper life and preventing the tendency to make light of death that occur in adolescence and the spread of suicides. In terms of nursing theory, the description and examination of the subjective structures and the characteristics of the different, types of school age children's perception of death can be utilized as useful material for building a model of school age children's perception of death, and be further used for teaching respect for life. In terms of nursing research, the results can contribute to research describing the effects of nursing intervention strategies and developing tools for providing psychosocial nursing in terms of giving school age children a positive perception of death according to their types as well respect for life.

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Development and Application of Practical Problem-based Teaching·Learning Process for Interacting with Neighbors (이웃과 더불어 살아가는 주생활을 위한 실천적 문제 중심 교수·학습 과정안 개발 및 적용)

  • Woo, Yeseul;Cho, Jaesoon
    • Journal of Korean Home Economics Education Association
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    • v.30 no.3
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    • pp.67-90
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    • 2018
  • The purpose of this study was to develop and apply the practical problem-based teaching·learning process plan for 'interacting with neighbors' of home economics subject. The plan consisting of 3 lessons has been developed and implemented according to the ADDIE model. Various activity materials (7 student's activity sheets, 3 reading texts, 1 homework sheet, 3 sets of ppt, 6 videos, and 3 teacher's reading texts) as well as questionnaire were developed for the 3-session lessons. The plans were implemented by the researcher to 204 freshmen, 8 classes, of C middle school in Seoul during september, 2017. The result, of students' lower level of actual participation in interacting with neighbors comparing to their interests in, supported the need of this study. Students were satisfied with the whole 3-lessons in the aspects such as beneficial usage of the contents in their daily life and in building the sense of community, as well as adequacy of materials and activities. Students also reported that they would highly aware to the importance of interacting with neighbors and to practice the contents learned from the lessons in daily life at community. They had an opportunity to reflect one's own attitude to neighbors and recommended to teach it to other schools, too. It can be concluded that the teaching·learning process plan for 'interacting with neighbors' would raise students' housing values living together and attain the overall objective and achievement standards of 2015 home economics middle school curriculum.

The Effect of Social Capital on Health-related Quality of Life - Using the Data of the 2019 Community Health Survey - (노인의 사회적 자본이 건강 관련 삶의 질에 미치는 영향 - 2019년 지역사회건강조사를 중심으로 -)

  • Kim, Ji-Hee;Park, Jong
    • Journal of agricultural medicine and community health
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    • v.46 no.4
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    • pp.280-294
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    • 2021
  • Objectives: The purpose of this study is to investigate the effects of social capital characteristics, socio-demographic characteristics, physical condition, and health behavior characteristics on health-related quality of life of the elderly in Korea. Methods: T-test, one-way ANOVA, and regression analysis were performed by applying a complex sample design to 57.787 people aged 65 and over using the 2019 Community Health Survey. Results: First, as a result of complex-sample T-test and ANOVA analysis, it was found that there were differences in health-related quality of life according to social capital characteristics, physical condition & health behavior characteristics, and socio-demographic characteristics. Complex Sample Regression Analysis Results, the explanatory power of the model was 28%. When living in the metropolitan area, living in an apartment building, having a spouse, having a higher household income, economic activity, higher educational attainment, increase sleeping time, walking time, frequent binge drinking, health checkup, networking, trust, and social participation showed higher health-related quality of life. When people were older, their gender was female, higher BMI, number of chronic diseases, and severe stress that showed lower health-related quality of life. Conclusions: It was proved that the factors affecting the health-related quality of life of the elderly are not only physical condition and health behavior factors, but also social capital and socio-demographic characteristics. It was found that the role as a member was important.

An Empirical Study on the Spatial Effect of Distribution Patterns between Small Business and Social-environmental factors (소상공인 점포의 분포와 환경요인의 공간적 영향관계에 관한 실증연구)

  • YOO, Mu-Sang;CHOI, Don-Jeong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.1
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    • pp.1-18
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    • 2019
  • This research measured and visualized the spatial dependency and the spatial heterogeneity of the small business in Cheonan-si, Asan-si with $100m{\times}100m$ grids based on global and local spatial autocorrelation. First, we confirmed positive spatial autocorrelation of small business in the research area using Moran's I Index, which is ESDA(Exploratory Spatial Data Analysis). And then, through Getis-Ord $GI{\ast}$, one kind of LISA(Local Indicators of Spatial Association), local patterns of spatial autocorrelation were visualized. These verified that Spatial Regression Model is valid for the location factor analysis on small business commercial buildings. Next, GWR(Geographically Weighted Regression) was used to analyze the spatial relations between the distribution of small business, hourly mobile traffic-based floating population, land use attributes index, residence, commercial building, road networks, and the node of traffic networks. Final six variables were applied and the accessibility to bus stops, afternoon time floating population, and evening time floating population were excluded due to multicollinearity. By this, we demonstrated that GWR is statistically improved compared to OLS. We visualized the spatial influence of the individual variables using the regression coefficients and local coefficients of determinant of the six variables. This research applied the measured population information in a practical way. Reflecting the dynamic information of the urban people using the commercial area. It is different from other studies that performed commercial analysis. Finally, this research has a differentiated advantage over the existing commercial area analysis in that it employed hourly changing commercial service population data and it applied spatial statistical models to micro spatial units. This research proposed new framework for the commercial analysis area analysis.

A Study on the Protection and Management System of the Southwestern Coast Tidal Flat for Inscription in the World Heritage List (서남해안 갯벌의 세계유산 등재를 위한 보호 및 관리체계 연구)

  • Moon, Kyong-O
    • Korean Journal of Heritage: History & Science
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    • v.48 no.3
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    • pp.80-95
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    • 2015
  • The purpose of this study is to establish an effective protection and management system for World Heritage (WH) nomination of Southwestern Coast Tidal Flat (SCTF) by proposing a model of protection and management. SCTF has a potential to become a representative best practice to achieve a sustainable development for human society. SCTF has a potential Outstanding Universal Values (OUVs) for WH nomination, thus a harmony between human and nature for wise use of natural resources needs to be pursued. It is required to present the system of SCTF's protection and management and to analyze present status of the regions in the Tentative List by comparing the case which were already inscribed as WH. For better protection of nominated areas, SCTF should expand an area for protection with additional designation. For the management system, two separate management systems such as the Department of Culture & Tourism and the Department of Oceans & Fisheries need to be reconciled. Because of this overlapping management structure, the management of the nominated sites has been inefficient and long-term management plan is lacking. Therefore, it is necessary to integrate conflicting management system of each local government and make a long-term, integrated management plan. To make an efficient and sustainable protection and management, it is essential to set up a collaboration system by integrating various stakeholders such as central and local governments, academic organizations, local residents, and NGOs. As in the case of Wadden Sea, the combined community system of the stakeholders mentioned above should be established. Because it is essential for local residents to understand a basic concepts for protection and management, it is necessary to establish capacity-building of local people. The protection and management structure should be set up by bottom-up processes, that is the proper structure shoud be based on thorough research on local society as well as thorough communication with local residents to make relevant laws and policies. This study also propose the proper plan for better conservation and management of SCTF.

Situations and Challenges of ODA for Sustainability of Asian Cultural Heritage (아시아 문화유산의 지속가능성을 위한 ODA 현황과 과제)

  • Yu, Jae Eun
    • Korean Journal of Heritage: History & Science
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    • v.49 no.3
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    • pp.270-285
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    • 2016
  • Various opinions and discussions have been actively in progress which are connected with cultural heritage since 'Sustainable Development Goals, SDGs' was announced by UN Sustainable Development Summit 2015 as Post-2015 Development Agenda. Apart from SDGs, conservation of cultural heritage itself stands on the basis of sustainability that originality, characteristic, diversity of cultural heritage should be permanently preserved. From that point of view, it is necessary to understand practical ODA for cultural heritage, far from theoretical approaches and policies. This paper is intended to look into the domestic and overseas situation related to ODA of Asian cultural heritage and the mentioned problems, future plans and challenges. First, the background and concepts about ODA were described and then ODA projects which have been carried out by Japan and China as typical ODA countries for Southeast Asia were introduced. ODA of cultural heritage in Korea has relatively recently started for restoration work for historic sites of Laos and Cambodia and its scale and performance do not come to much yet. Therefore, to develop ODA of cultural heritage, there are suggestions as in the followings. First, it is necessary to have a long-term master plan of ODA projects for sustainability of cultural heritage. Second, based on the view from the long-term perspective, the selection and focus for ODA partner countries should be considered, avoiding short-term projects aiming at a number of countries. Not widespread existing projects by other countries, but the model of Korean ODA for cultural heritage only Korea can conduct should be prepared. The next thing is connection with sustainability, and ultimately the conservation of cultural heritage should result in benefit to the natives by giving an impetus to economy as well as fostering tourism of local areas. To accomplish that connection, educational training and building capacity are suggested as the most suitable alternatives. Cultural heritage of each country reflects its indigenous originality and characteristics, therefore, the restoration work should be conducted by people in each country as the best way. From this point of view, ACPCS held by National Research Institute of Cultural Heritage will take a role of a specialized training program in Korean way. Lastly, establishment of a control tower for ODA in Korea is necessary. JCIC(Japan Consortium for International Cooperation in Cultural Heritage), which was set up in Japan for sharing information, establishment of cooperation system and prevention of overlapped projects will be an example we can take into consideration.

Preparation and Characterization of Bamboo-based Activated Carbon by Phosphoric Acid and Steam Activation (인산 및 수증기 활성화에 의한 대나무 활성탄 제조 및 특성 연구)

  • Park, Jeong-Woo;Ly, Hoang Vu;Oh, Changho;Kim, Seung-Soo
    • Clean Technology
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    • v.25 no.2
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    • pp.129-139
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    • 2019
  • Bamboo is an evergreen perennial plant, and it is known as one of the most productive and fastest-growing plants in the world. It grows quickly in moderate climates with only moderate water and fertilizer. Traditionally in Asia, bamboo is used for building materials, as a food source, and as versatile raw materials. Bamboo as a biomass feedstock can be transformed to prepare activated carbon using the thermal treatment of pyrolysis. The effect of process variables such as carbonization temperature, activation temperature, activation time, the amount of steam, and the mixing ratio of phosphoric acid and bamboo were systematically investigated to optimize the preparation conditions. Steam activation was proceeded after carbonization with a vapor flow rate of $0.8{\sim}1.8mL-H_2O\;g-char^{-1}\;h^{-1}$ and activation time of 1 ~ 3 h at $700{\sim}900^{\circ}C$. Carbon yield and surface area reached 2.04 ~ 20.59 wt% and $499.17{\sim}1074.04m^2\;g^{-1}$, respectively, with a steam flow rate of $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$ for 2 h. Also, the carbon yield and surface area were 24.67 wt% and $1389.59m^2\;g^{-1}$, respectively, when the bamboo and phosphoric acid were mixed in a 1:1 weight ratio ($700^{\circ}C$, 2 h, $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$). The adsorption of methylene blue into the bamboo activated carbon was studied based on pseudo first order and second order kinetics models. The adsorption kinetics were found to follow the pseudo second order model, which is governed by chemisorption.

Analysis the Appropriate Schedule for the Installment Payment Amount and Establishment of the Post sale System and Policy in the Apartment Construction (공동주택 건설사업에서 후분양의 제도 및 정책 수립을 위한 분담금 납부 적정시기 분석)

  • Yoon, Inhwan;Bae, Byungyun
    • Korean Journal of Construction Engineering and Management
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    • v.22 no.4
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    • pp.59-65
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    • 2021
  • Since the 2016 "Housing Act Partial Amendment" and the "2018 Housing Comprehensive Amendment Plan", interest in the pre sale system and post sale system of apartment houses has been on the rise. In order to compare the advantages and disadvantages of the pre sale system and the post sale system of apartment houses, and to establish the basis for the institutional policy of the post sale system, a questionnaire survey method was used for tenants of the apartment house from the public side, and issues of time and cost. The time series analysis method is intended to suggest an appropriate time for payment of contributions. Accordingly, through a review of existing theories and literature, the post sale system of public and private institutions was organized, and through a questionnaire survey, the path to securing pre sale money, product information of the model house, and the degree of awareness of the effect of the post sale system were investigated. For the post sale fund support and payment method, it is necessary to increase the commercial line for existing financiers from the user's point of view, and it is necessary to operate in consideration of the economic power of the pre sale market by region. Both 60% post sale and 80% post sale have a price range of up to KRW 10 million, and the total interest rate is 5.0%, and the annual interest rate is about 2.8% for 60% post sale, and about 2.1% for 80% post sale, which is lower than the current 3.1%. I need an interest rate. The research is a perception survey targeting a total of 5,213 households in a sample of after sale apartments in public institutions. As the actual values are analyzed using a time series on the effects of market supply and demand and market prices, there is a limit to applying them to prospective residents of private apartments. In addition, to respond to first time tenants, a questionnaire survey was conducted on five complexes that have moved in within the last five years.