• Title/Summary/Keyword: cities

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Proposal for Research Model of Agricultural and Fishery Farm Tower (수직형 농축수산 팜의 연구 모델 제안)

  • Young-Su Lee;Seung-Jung Shin
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.24 no.3
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    • pp.69-76
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    • 2024
  • This dissertation developed a five-story vertical livestock and fisheries farm (palm tower) model for sustainable food production in cities. It proposes to integrate marine farms, livestock raising, and pesticide-free automated crop farms to efficiently use resources and minimize environmental impact. Based on circular economy principles, the model can recycle the output of each part into resources from the other, increasing the efficiency of the system, utilizing idle space in the city, and promoting job creation and community participation. It can also contribute to reducing the carbon footprint of food production and improving food safety. In addition, the study explores how advanced agricultural technologies can be integrated into urban structures to address global food security challenges. This model presents potential solutions to the food crisis caused by climate change and population growth, and suggests a direction for the development of urban agriculture. Future research should address the technical and policy challenges for practical implementation.

Growing Environment and Vegetation Structure of Cudrania tricuspidata Habitats (꾸지뽕나무 자생지의 생육환경과 식생구조)

  • Jeong-Woon Joo;Su-Gyeong Jeon;Seong-Hun Jeong;Hyun-Shik Moon
    • Journal of Environmental Science International
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    • v.33 no.7
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    • pp.477-487
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    • 2024
  • This study aimed to identify the growth environment of Cudrania tricuspidata by analyzing the site environment, soil characteristics, and vegetation structure of the species habitats and to provide basic data for identifying suitable cultivation sites for mass production. The study was conducted on 17 sites in five cities/counties of Gyeongnam and Jeonnam province. It was found that C. tricuspidata habitats were mainly distributed on gentle slopes in the southeast and southwest, with an average altitude of approximately 290 m. The soil of the C. tricuspidata habitats was sandy loam with a high proportion of sand, averaging 73.9%, 4.6%, and 21.5% sand, silt, and clay, respectively. The soil had a pH value of 5.41 (5.20-5.79), organic matter content of 8.2% (3.6-12.6%), total nitrogen content of 0.36% (0.19-0.54%), available phosphorus content of 3.50 ppm (0.95-7.61 ppm), and cation exchange capacity of 15.9 cmol+/kg (10.0-20.7 cmol+/kg) on average. The vegetation structure analysis showed that C. tricuspidata appeared in the tree layers of regions A (Jinju) and E (Yeosu), but the importance of C. tricuspidata was found to be high in the subtree and shrub layers in all regions. The ecological niche breadth was widest (0.874) in region B (Hadong) and narrowest (0.480) in region E (Yeosu).

Steel Design of Continuously Reinforced Concrete Pavement based on the Width of Transverse Crack (횡방향 균열 폭에 기초한 연속철근 콘크리트포장의 철근설계)

  • Kim, Kyeong-Jin;Kim, Dong-Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.13 no.1 s.53
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    • pp.106-114
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    • 2009
  • The steel design based on the width of transverse crack which is the major factor to affect a long-term performance of continuously reinforced concrete pavement was developed. For this study, twenty-one cities of Texas were selected and the temperature data was collected at those locations during the past ten years. From the data, zero-stress temperatures were calculated by the PavePro program and the widths of transverse crack were analyzed by the CRCP program. The variables used to this numerical analysis were slab thickness, coefficient of thermal expansion of concrete, steel ratio, and design temperature. The total of 448 factorial runs were made and the regression analysis was performed using the results. Steel ratios from the regression equations were backcalculated and a steel design table was proposed.

The Influence of the Early Childhood Teacher's Interpersonal Ability and Subjective Well-Being on Emotional Expressiveness (영유아 교사의 대인관계 유능성 및 주관적 안녕감이 정서표현성에 미치는 영향)

  • In-Sook Choi
    • Journal of the Health Care and Life Science
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    • v.10 no.1
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    • pp.81-88
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    • 2022
  • The purpose of this study is to analyze the relationship between interpersonal competence, subjective well-being, and emotional expressiveness of early childhood teachers, and to investigate the effect of interpersonal competence and subjective well-being on emotional expressiveness. For this purpose, in this study, a survey was conducted with 341 teachers of infants and toddlers working in kindergartens and daycare centers located in I and G cities. The research tools used in this study were ICQ, ESS, PANA and SWLS scales. Results of the study First, as a result of examining the correlation between interpersonal competence, subjective well-being, and emotional expression, it was found that among subjective well-being, there was a positive correlation in addition to negative emotions. Second, as a result of examining the effect of early childhood teachers' interpersonal competence and subjective well-being on emotional expression, it was found that they had a statistically significant effect in part.

Association between exposure to particulate matter and school absences in Korean asthmatic adolescents

  • Seongmin Jo;Kiook Baek;Joon Sakong;Chulyong Park
    • Annals of Occupational and Environmental Medicine
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    • v.34
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    • pp.21.1-21.13
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    • 2022
  • Background: Because particulate matter (PM) and asthma are closely related, the prevalence of school absence among adolescents with asthma can be affected by the concentration of PM. We aimed to investigate the relationship between school absences due to asthma and the total number of days that the PM concentration exceeded the standard. Methods: We used the data from the 16th Korea Youth Risk Behavior Survey and the PM levels of 17 metropolitan cities and provinces gathered from the AirKorea. Information on the characteristics of asthmatic adolescents and the prevalence of school absence was obtained using a questionnaire, while the PM levels based on the total number of days with poor and very poor PM grades were collected from the AirKorea website. Both χ2 test and logistic regression analysis were performed using the weights presented in the original dataset. Results: In the case of particulate matter of 10 microns in diameter or smaller (PM10), the odds ratio (OR) after adjusting for confounders (sex, school year, body mass index, smoking history, diagnosis of allergic rhinitis, diagnosis of atopic dermatitis and city size) was 1.07 (95% confidence interval [CI]: 1.01-1.13) for absents due to asthma when the total days of poor and very poor grades of PM10 (81 ㎍/m3 or higher) increased by 1 day. In the analysis of particulate matter of 2.5 microns in diameter or smaller (PM2.5), the OR after adjusting for confounders was 1.01 (95% CI: 1.00-1.03) for absents due to asthma when the total number of days with poor and very poor PM2.5 grades (36 ㎍/m3 or higher) increased by 1 day. Conclusions: A significant association was observed between the total number of days of poor and very poor PM10 and PM2.5 grades and school absence due to asthma; PM can cause asthma exacerbation and affect the academic life.

Long Term Behavior of Permanent Rock Anchorages in Large Spatial Span Structures (대공간구조물에 시공된 영구앵커의 장기거동)

  • Yoo, Nam-Jae;Kim, Dae-Hak;Park, Byung-Soo;Kim, Jae-Il;Lee, Jong-Yong
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.10 no.6
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    • pp.123-135
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    • 2006
  • Most of all, large spatial span structures are the symbol of cities but have to get to supply the purpose of structure simultaneously, therefore their foundations are designed to get rolls of structure support, structure shape maintenance or overturn prevention, buoyancy resistance, etc. Accordingly various type foundations have been introduced, and after anchorage power is introduced for double structures shape maintenance and overturn prevention, change of anchorage power checked in the construction process is reviewed, comparing of playground case. Case1 anchors for the control of horizontal power worked outside hemisphere type roof, Case2 anchors for the overturn prevention of cantilever roof examined in this example. The examination has been executed by the analysis of anchorage power introduction process, related test results and anchorage power monitoring results for 2 examples.

Passenger Demand Forecasting for Urban Air Mobility Preparation: Gimpo-Jeju Route Case Study (도심 항공 모빌리티 준비를 위한 승객 수요 예측 : 김포-제주 노선 사례 연구)

  • Jung-hoon Kim;Hee-duk Cho;Seon-mi Choi
    • Journal of Advanced Navigation Technology
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    • v.28 no.4
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    • pp.472-479
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    • 2024
  • Half of the world's total population lives in cities, continuous urbanization is progressing, and the urban population is expected to exceed two-thirds of the total population by 2050. To resolve this phenomenon, the Korean government is focusing on building a new urban air mobility (UAM) industrial ecosystem. Airlines are also part of the UAM industry ecosystem and are preparing to improve efficiency in safe operations, passenger safety, aircraft operation efficiency, and punctuality. This study performs demand forecasting using time series data on the number of daily passengers on Korean Air's Gimpo to Jeju route from 2019 to 2023. For this purpose, statistical and machine learning models such as SARIMA, Prophet, CatBoost, and Random Forest are applied. Methods for effectively capturing passenger demand patterns were evaluated through various models, and the machine learning-based Random Forest model showed the best prediction results. The research results will present an optimal model for accurate demand forecasting in the aviation industry and provide basic information needed for operational planning and resource allocation.

Mental Health of Medical Students After Combating the COVID-19 Epidemic: A Cross-sectional Study in Vietnam

  • Duc Minh Cap;Anh Quang Nguyen;Tham Thi Nguyen
    • Journal of Preventive Medicine and Public Health
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    • v.57 no.4
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    • pp.347-355
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    • 2024
  • Objectives: This study was conducted to investigate the prevalence of mental health (MH) symptoms and associated factors among medical students who were engaged in combating the coronavirus disease 2019 (COVID-19) epidemic in 4 provinces/cities of Vietnam. Methods: A cross-sectional study with 580 participants was conducted at a medical university in Northern Vietnam. MH was assessed using the 21-item Depression, Anxiety, and Stress Scale, which was previously standardized in Vietnam. Data were collected through a structured self-administered questionnaire. Multivariate logistic regression was employed to examine the association between MH symptoms and relevant factors. Results: Out of a total of 2703 medical students, 21.5% responded to the questionnaire. Among the 580 respondents, the prevalence rates of depression, anxiety, and stress were 43.3%, 44.0%, and 24.7%, respectively. Factors significantly associated with self-reported depression included being female and having a COVID-19 infection. Similarly, being female and having a COVID-19 infection were significantly associated with self-reported anxiety. Factors associated with self-reported stress included being female, having a personal or family history of MH symptoms, working more than 8 hr/day, and having a COVID-19 infection. Conclusions: COVID-19 has adversely impacted the MH of medical students. Our findings are valuable in their potential to motivate universities, MH professionals, and authorities to offer mental healthcare services to this group. Furthermore, there is a pressing need for training courses designed to equip future healthcare workers with the skills to manage crises effectively.

Analyzing the Projection of Physician Workforce Supply and Demand in Gyeongsangnam-Do, South Korea, through System Dynamics (시스템 다이내믹스를 활용한 경상남도 의사인력 수급추계를 통한 적정성 연구)

  • Youngsoo Kim;Beak-Geun Jeong;Gyeong-Min Lee
    • Journal of agricultural medicine and community health
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    • v.49 no.3
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    • pp.235-256
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    • 2024
  • Background: The adequate provision of medical care relies on the availability of a suitable number of healthcare professionals. To ensure stability in healthcare delivery, it is crucial for a country to accurately estimate and address the supply of doctors. This study aims to contribute to the formulation of effective policies for securing and distributing doctor manpower, with a focus on medically underserved areas at both the national and local government levels. Methods: Employing the system dynamics methodology, this research utilizes stock and flow diagrams, including level and rate diagrams, to quantitatively analyze the cumulative structure of the doctor supply and demand system. Results: The analysis reveals a substantial shortage of clinical doctors in Gyeongsangnam-do, amounting to 15,477 as of 2021. Projections indicate a need for an additional 7,570 doctors by the year 2050 to maintain the current healthcare service level. Examination of medical treatment rights and distribution across cities and counties indicates an insufficiency in doctor supply relative to demand in the majority of regions. Alternative scenarios, such as increasing medical school enrollments and adjusting retirement ages, were explored, yet none provided a sufficient resolution to the shortage. Conclusion: The findings underscore an impending exacerbation of the doctor shortage in Gyeongsangnam-do if the existing system is perpetuated. Addressing this issue necessitates not only augmenting the number of medical school students and adapting retirement age policies but also implementing diverse strategies employed successfully in other countries. This study serves as a foundational step in informing evidence-based policies aimed at securing an ample and appropriately distributed doctor workforce for sustainable healthcare delivery.

Decision Tree Generation Algorithm for Image-based Video Conferencing

  • Yunsick Sung;Jeonghoon Kwak;Jong Hyuk Park
    • Journal of Internet Technology
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    • v.20 no.5
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    • pp.1535-1545
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    • 2019
  • Recently, the diverse kinds of applications in multimedia computing have been developed for visual surveillance, healthcare, smart cities, and security. Video conferencing is one of core applications among multimedia applications. The Quality of Service of video conferencing is a major issue, because of limited network traffic. Video conferencing allow a large number of users to converse with each other. However, the huge amount of packets are generated in the process of transmitting and receiving the photographed images of users. Therefore, the number of packets in video conferencing needs to be reduced. Video conferencing can be conducted in virtual reality by sending only the control signals of virtual characters and showing virtual characters based on the received signals to represent the users, instead of the photographed images of the users, in real time. This paper proposes a method that determines representative photographed images by analyzing the collected photographed images of users, using KMedoids algorithm and a decision tree, and expresses the users based on the analyzed images. The decision tree used for video conferencing are generated automatically using the proposed method. Given that the behaviors in the decision tree is added or changed considering photographed images, it is possible to reproduce the decision tree by photographing the behavior of the user in real-time. In an experiment conducted, 63 consecutively photographed images were collected and a decision tree generated by using the silhouette images of the photographed images. Indices of the silhouette images were utilized to express a subject and one index was selected using a decision tree. The proposed method reduced the number of comparisons by a factor of 3.78 compared with the traditional method that uses correlation coefficient. Further, each user's image could be outputted by using only the control image table of the image and the index.