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Study on Factors of Vacant Houses's Occurrence using Spatio-Temporal Model (시공간 종속성을 고려한 빈집발생 요인 추정에 관한 연구)

  • You-Hyun KIM;Donghyun KIM
    • Journal of the Korean Association of Geographic Information Studies
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    • v.26 no.2
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    • pp.20-41
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    • 2023
  • Recently, urban shrinkage due to low birth rate and aging population and the decline of local cities are causing a new urban problem of empty houses. This study examines the distribution of vacant homes using spatial panel data collected from 2015 to 2019 at local administraitve districts and estimates the factors of vacant house occurrence using a spatial panel model considering spatio-temporal dependency. As a result, the spatio-temporal dependence of vacant houses was identified and it was estimated using spatial panel model not OLS model. Based on the spatial panel model, it was found that the most influential factor in the occurrence of vacant houses was the housing-related factor. This result shows that policy considerations for housing supply are necessary for the management of vacant housing as well as population movement and poor infrastructure.

A QUALITATIVE SURVEY ON SUCCESS FOR MAINTENANCE PROJECTS

  • Albert P C Chan;Daniel W M Chan;Edmond W M Lam
    • International conference on construction engineering and project management
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    • 2007.03a
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    • pp.186-195
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    • 2007
  • Key Performance Indicators (KPIs) are the criteria of measuring project performance in order to attain construction excellence. Previous researchers have examined the abstract concept of success for general new construction and identified its relationship with the factors of success. In fact, most buildings exist to satisfy the needs of people. With the passing of time and change in technology, buildings have to be maintained and renovated in order to continue functioning properly for the benefits of users. Therefore, criteria and factors of success have increasingly attracted the attention of both researchers and practitioners, especially in cities where buildings become ageing. However, the topic of project success for maintenance projects is less discussed in previous research, and project participants, including maintenance surveyors should be able to identify the success measurement and its associated factors for performance improvement. This study fills the research gap by investigating the criteria and factors of success for maintenance projects. It first provides a summary of the literature review on the criteria and factors of success for construction projects. An empirical study has also been carried out with ten practitioners in Hong Kong to further identify the criteria and factors critical for the success of maintenance projects in practice. While most criteria and factors of success for new construction projects are also applicable to maintenance projects, participants in maintenance projects believe that effective communication is in particular important to provide quality service to the end-users.

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A Review of Urban Flooding: Causes, Impacts, and Mitigation Strategies (도시 홍수: 원인, 영향 및 저감 전략 고찰)

  • Jin-Yong Lee
    • The Journal of Engineering Geology
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    • v.33 no.3
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    • pp.489-502
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    • 2023
  • Urban floods pose significant challenges to cities worldwide, driven by the interplay between urbanization and climate change. This review examines recent studies of urban floods to understand their causes, impacts, and potential mitigation strategies. Urbanization, with its increase in impermeable surfaces and altered drainage patterns, disrupts natural water flow, exacerbating surface runoff during intense rainfall events. The impacts of urban floods are far-reaching, affecting lives, infrastructure, the economy, and the environment. Loss of life, property damage, disruptions to critical services, and environmental consequences underscore the urgency of effective urban flood management. To mitigate urban floods, integrated flood management strategies are crucial. Sustainable urban planning, green infrastructure, and improved drainage systems play pivotal roles in reducing flood vulnerabilities. Early warning systems, emergency response planning, and community engagement are essential components of flood preparedness and resilience. Looking to the future, climate change projections indicate increased flood risks, necessitating resilience and adaptation measures. Advances in research, data collection, and modeling techniques will enable more accurate flood predictions, thus guiding decision-making. In conclusion, urban flooding demands urgent attention and comprehensive strategies to protect lives, infrastructure, and the economy.

Evaluation of Applicability of CMD-SOIL using the Deep Mixing Method in Ulsan Area for the Construction of Coastal Structure Foundation (해안구조물 기초의 건설을 위해 울산지역에서의 심층혼합공법을 사용한 CMD-SOIL의 적용성 평가)

  • Jae-Hyun Park;Kwang-Wu Lee;Kyong-Ju Mun;Dae-Sung Cho
    • Journal of the Korean Geosynthetics Society
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    • v.22 no.3
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    • pp.61-69
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    • 2023
  • As global trade and maritime port environments change, the need to respond to larger and faster ships is increasing. Accordingly, new ports are being built around metropolitan cities such as Busan and Ulsan. In general, a compaction method using sand or gravel is applied to the construction of a new port. However, due to the lack of sand or gravel and the difficulty in securing economic feasibility due to the increase in unit price, the deep mixing method has recently been used. Therefore, in this study, CMD-SOIL using circulating resources was applied to the Ulsan area, and the applicability was determined by analyzing the laboratory mixing test and boring results at in-situ. As a result of the test, it was analyzed that it showed more than the design mixing strength, and it was possible to secure the similar performance as blast furnace slag cement. In addition, it was analyzed that the design standard strength can be sufficiently secured as a result of in-situ boring. Therefore, considering the field applicability in the Ulsan, it is judged that the use of CMD-SOIL is possible.

A Study on Generating Public Library Service Areas Considering User Access Patterns (이용자의 접근 패턴을 고려한 공공도서관 서비스 영역 생성 연구)

  • Woojin Kang;Jongwook Lee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.34 no.3
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    • pp.89-107
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    • 2023
  • Public libraries should plan and provide services that satisfy various needs of the local community users. In order to understand library users, it is essential first to grasp the service areas of libraries. The current service areas of public libraries are primarily set based on administrative boundaries of the areas where the libraries are located, which limits the consideration of actual user access patterns to the libraries. In this study, we aim to create service areas that incorporate the transportation and geographical characteristics of the library's surroundings and reflect the access patterns of library users. Specifically, we utilized street network data from 502 libraries in 7 metropolitan cities to determine the travel distance and time from user locations, considering gradients, to the libraries. Subsequently, we applied the shortest path algorithm to generate service areas within a 30-minute walking or driving range. As a result, we confirmed that there are differences in the service area patterns of libraries depending on topographical factors, and this better reflects the realistic conditions of library access compared to service areas based on straight-line distances. This method of generating service areas contributes to a more accurate understanding of library users' numbers, characteristics, and needs.

A Study on Asset Preference Characteristics of Millennials and Gen Z

  • Eun-sung PARK;Jae-tae KIM
    • The Journal of Economics, Marketing and Management
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    • v.11 no.4
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    • pp.19-30
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    • 2023
  • Purpose: This study examines the factors that the Millennials and Gen Z prefers to invest in assets. We look at the asset structure they want now and in the future and the idea of designing the future. This can be expected that the center of Korea's asset market will change to the structure they want in the future. Research design, data and methodology: The spatial extent of the study is all over Korea including Seoul, the metropolitan area, and local cities. The survey was conducted for about 16 days from May 7 to May 22, 2023. The survey was conducted by the surveyor visiting the subject in person, distributing the questionnaire, explaining it, and filling it out in person. For the analysis, descriptive statistics and logistic regression analysis were conducted using the SPSS 25.0 statistical package. Results: It was confirmed that the preferred assets of the Millennials and Gen Z were different by period. There was also a difference in the influencing factors between Millennial Generation and Generation Z in asset preference. Conclusions: The Millennials and Gen Z's preferred assets were different by period. The reason is interpreted as the current process of collecting assets during the asset formation period. In the future, they intend to purchase real estate assets by using financial assets as a lump sum of money. We learned the characteristics of the entire Millennials and Gen Z, in addition, the difference between income and assets is believed to have affected the difference in preference factors of Millennial Generation and Generation Z, respectively.

Analysis of Regional Development Attractiveness of Comprehensive Air-quality Index and Gross Domestic Product - Focusing on Cities and Counties in Chungcheongnam-do - (통합대기환경지수와 지역내총생산에 의한 지역개발매력도 분석 - 충청남도 시·군을 대상으로 -)

  • Lee, Byung-Hark;Jung, Nam-Su
    • Journal of Korean Society of Rural Planning
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    • v.29 no.3
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    • pp.91-97
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    • 2023
  • The purpose of this research is to apply the regional development attractiveness of the national level determined in the previous study to the city and county level of Chungcheongnam-do. We verified results with the population change of the floating population data. In order to measure regional development attractiveness in 2020, Chungcheongnam-do's integrated air environment index and per capita gross regional product were gathered. Population movement data over the past five years have been used to analyze population changes in the floating population data. Regional development attractiveness depended on the data of GDP per capita, which had a large difference between the maximum and minimum values. The rate of increase or decrease in population change by city and county in Chungcheongnam-do over the past five years has changed significantly since 2021 and characteristics of each group were grouped into four groups. Based on the environment and economic feasibility of the region, it can be the starting point for a new analysis of Korea's regional development projects and the selection of target sites. Policy suggestions can also be made in spatial plans such as short-term comprehensive plans, long-term comprehensive plans, and development plans. It can be a limit of this research that regional development attractiveness was determined by the relatively large per capita gross domestic product. It is necessary to further develop regional development attractiveness by closely investigating the characteristics of the region, social problems, and emissions of environmentally harmful substances.

An Empirical Study on Fear and Dizziness Using UAM Simulator (UAM 시뮬레이터를 활용한 공포심과 어지러움에 대한 실증 연구)

  • Se-Jun Kim
    • Journal of Advanced Navigation Technology
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    • v.27 no.3
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    • pp.262-268
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    • 2023
  • Based on the government's willingness to commercialize UAM with the goal of 2025, it is making remarkable achievements in various fields, including the development of UAM. In addition, based on the concept of UAM, it is evolving into an Advanced Air Mobility(AAM) concept that includes commercial operation between long-distance or short-range cities, cargo delivery, public services, aviation tourism, and personal/leisure aircraft. however, research on physical problems such as low-altitude operation characteristics, speed within three dimensions, and dizziness caused by external environment has yet to be found. Therefore, in this study, actual images are taken while flying at the expected altitude and speed of UAM using a helicopter, and by experiencing it to the general public using a UAM simulator equipped with VR and Motion, physical reactions such as fear and dizziness of passengers that may occur during actual UAM operation of UAM are analyzed.

A Study on the Establishment of Education and Training Program for Urban Air Mobility(UAM) Pilot in Korea (국내 도심항공모빌리티(UAM) 조종사 교육·훈련제도 수립 방안 연구)

  • Young-jin Cho;Chul Park;Se-Hoon Yim
    • Journal of Advanced Navigation Technology
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    • v.27 no.4
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    • pp.330-336
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    • 2023
  • Rapid urbanization is rapidly progressing around the world, and urban problems such as traffic congestion, environmental pollution, and noise pollution are emerging, due to this urban concentration phenomenon, logistics and transportation costs are increasing. Urban Air Mobility(UAM) is a three-dimensional futuristic urban transportation that is expected to become an important transportation axis of smart cities as a service(MaaS) linked to roads, railways, and personal transportation. However, as of July 2023, research on airspace systems, Bertieport design, navigation, and communication for UAM operation is actively being conducted, but little research has been conducted on the concept of pilot education and training and education and training programs. Therefore, this paper aims to present a suitable plan for the domestic pilot training system through SWOT analysis of vertical takeoff and landing(VTOL) pilot education and training programs in the United States and Europe.

Estimation of Mercury Exposure from School Meals for Lower Grades of Elementary Schools in Korea (국내 초등학교 저학년 급식 식단을 기반으로 한 수은 노출량 분석)

  • Boin Yu;Yoo Kyoung Park
    • Journal of the Korean Dietetic Association
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    • v.29 no.3
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    • pp.140-156
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    • 2023
  • Children are very sensitive to exposure to heavy metals such as mercury which can accumulate in the body. Exposure to even low concentrations of such metals is reported to be very harmful to health. An evaluation of the mercury content of meals in public elementary schools could provide information which could be used to reduce this level. Two public elementary schools were selected from 16 cities and provinces. The meals provided were analyzed in the third week of spring, summer, fall, and winter. The average mercury allowance per meal was calculated using the provisional tolerable weekly intake (PTWI) established by the government. The number of instances of excess content observed was compared by region based on the mercury allowance per meal, and the frequency of use of mercury-containing marine products that cause the excessive levels was identified. The results of analyzing a total of 575 menus revealed that the use of marine and processed marine products with a high mercury content was more in the coastal areas. The mercury content in school meals was also higher in coastal areas than in inland areas. Conversely, in inland areas, the frequency of intake of marine products and marine products with a high mercury content was low, and the amount of mercury intake in school meals was also correspondingly low. In conclusion, this study intended to provide information that could be used to make school meal menus safer. This data can be used to replace school meal menus with high mercury content in coastal areas with menus with low mercury content.