• 한국환경복원기술학회지
• /
• 제15권2호
• /
• pp.127-136
• /
• 2012

Global climate change and urban heat island have been the main factors which changed leaf burst timing and leaf growth performance in urban forests. Therefore, the ecosystem in urban forests were modified and the types and composition of wildlives, living in the urban forests, were desperately changed due to the urban heat island. This study was done to identify phenological phenomena appeared in urban forests due to the urban climate change by comparing the morphological changes of leaves due to the change of temperature in Spring. The study focused on nine urban forests distributed in Daegu city, where weekly temperature and the morphological changes of the plants were mainly observed. Urban forests had different temperature depending on where each was located in the urban area. The difference of temperature in forests in and outside the urban area was verified by SPSS (Statistical Package for the Social Sciences), which divided the urban forests into about three groups; the one located outside the city, another group located in the middle of the city, and the other located close to the outside forests. The forests located in the middle of the city were showing the earlier leaf burst timing and leaf growth performance, while forests, distributed outside the city, were showing relatively late leaf burst timing and leaf performance.

• 국제초고층학회논문집
• /
• 제5권2호
• /
• pp.87-94
• /
• 2016

High-rise as a building typology is gaining popularity in Asian mega-cities, due to its advantages in increasing volumetric density with limited land resources. Numerous factors contribute to the formation of high-rise urban form, from economical and institutional, environmental to socio-political. Environmental concerns over the impact of rapid urbanization in developing economies demand new thought on the link between urban environment and urban form. Outdoor and indoor climate, pedestrian comfort, and building energy consumption are all related to and impacted by urban form and building morphology. There are many studies and practices on designing individual "green" high-rise buildings, but far fewer studies on designing high-rise building clusters from the perspective of environmental performance optimization.. This paper focuses on the environmental perspective, and its correlation with the evolution of the high-rise urban form. Previous studies on urban morphology in terms of environmental and energy performance are reviewed. Studies on "parameterizing" urban morphology to estimate its environmental performance are reviewed, and the possible urban design implications of the study are demonstrated in by the author, by way of a microclimate map of the iconic Shanghai Xiao Lujiazui CBD. The study formulates the best-practice design guidelines for creating walkable and comfortable outdoor space in a high-rise urban setting, including proper sizing of street blocks and building footprint, provision of shading, and facilitating urban ventilation.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2006년도 추계학술대회 논문집
• /
• pp.288-293
• /
• 2006

In this work, the characteristics and the improving method of train performance of Korean rubber-tired AGT system(K-AGT) and Urban MAGLEV system are evaluated by using Train Performance Simulation(TPS). The train performance characteristics of K-AGT were analysed according to the change of maximum running speed and those of Urban MAGLEV were evaluated according to a vehicle weight variation. In the result of simulation in virtual line, the scheduled speed and the running time of K-AGT system have no difference with Urban MAGLEV system if the maximum running speed is equal. But the energy consumption of Urban MAGLEV system is more than that of K-AGT system. The analyses showed that in case of a 20 percent vehicle weight reduction of Urban MAGLEV system, the energy consumption per person is similar with the K-AGT system. The Urban MAGLEV system is more efficient in long travel distance condition than in short running distance condition in the aspect of train performance.

• Journal of Positioning, Navigation, and Timing
• /
• 제12권4호
• /
• pp.379-389
• /
• 2023

According to the Korea Urban Air Mobility (K-UAM) Concept of Operation (ConOps), the Global Navigation Satellite System (GNSS) is recommended as the primary navigation system and the performance specification will be implemented considering the standard of Performance Based Navigation (PBN). However, by taking into account the characteristics of an urban environment and the concurrent operations of multiple UAM aircraft, the current PBN standards for civil aviation seem difficult to be directly applied to an UAM aircraft. Therefore, by referring to technical documents published in the literature, this paper examines the feasibility of applying the proposed performance requirements to K-UAM, which follows the recommendation of navigation performance requirements for K-UAM. In accordance with the UAM ConOps, the UAM aircraft is anticipated to maintain low altitude during approach and landing phases. Subsequently, the navigation performance degradation could occur in the urban environment, and the primary degradation factor is identified as multipath error. For this reason, to ensure the safety and reliability of the K-UAM aircraft, it is necessary to analyze the degree of performance degradation related to the urban environment and then propose an alternative aid to enhance the navigation performance. To this end, the aim of this paper is to model the multipath effects of the GNSS in an urban environment and to carry out the simulation studies using the real GNSS datasets. Finally, the initial navigation performance requirement is proposed based on the results of the numerical simulation for the K-UAM.

• 국제학술발표논문집
• /
• The 3th International Conference on Construction Engineering and Project Management
• /
• pp.1463-1467
• /
• 2009

Construction projects are vulnerable to diverse internal and external factors, requiring systematic and consistent performance management along the entire life cycle of a project. In particular, urban renewal projects have a range of performance measures, including policy reconciliation and permits, project development, project financing, design, construction, and occupancy and maintenance. This requires a program-level megaproject approach, which integrates each stage of a project as well as variety of stakeholders' interests in pursuing a project from different perspectives. However, previous research on performance management has focused especially on the limited scopes of factors, including cost, quality, and schedule at the project level or on financial factors at the firm level. Given the lack of current approaches, this study suggests an integrated and systematic performance management scheme to control urban renewal megaprojects at the broadened perspectives of the program level. To this end, this study adopts the balanced scorecard approach and elicits key performance indices associated with various project configurations. Finally, an algorithm is presented for quantitatively assessing the level of performances along whole life cycle of urban renewal megaprojects.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.1539-1543
• /
• 2011

Due to recent large earthquakes around the world, there are increasing social needs for seismic safety of urban railway infrastructures. Urban railway infrastructures are applied different seismic performance evaluation procedure each of overground structures, underground structures and bridge structures, and the characteristics of urban railway infrastructures are not properly considered in the procedure. This study presents problems in the existing seismic performance evaluation procedure of urban railway infrastructures and proposes necessities of unified evaluation procedure.

• 지역연구
• /
• 제39권1호
• /
• pp.21-36
• /
• 2023

사회·경제적 여건 변화에 따른 저성장시대에 진입하며, 전국 대부분의 도시에서 도시재생을 적극적으로 추진하고 있다. 도시재생은 막대한 국가재정이 투입된 사업임에도 불구하고, 아직 명확한 평가시스템이 마련되지 못하였다. 도시재생사업의 지속가능성을 담보하기 위해 도시재생사업의 성과를 평가하고, 정책을 보완하기 위한 환류체계 구축이 필요하다. 본 연구에서는 도시재생사업의 성과를 평가하기 위한 공간 빅데이터 기반의 도시재생성과 평가기법을 개발하는 것을 목적으로 한다. 도시재생성과 평가기법은 도시재생사업 유형, 대도시·중도소시 여부 등을 기준으로 도시재생사업 영향권을 차등화하였다. 인구·사회, 산업·경제, 물리·환경 측면 평가지표의 도시재생사업 영향권 내부·외부 간의 상대적 비교를 통해, 도시재생사업의 성과를 정량적으로 측정하였다.

• 한국CDE학회논문집
• /
• 제15권1호
• /
• pp.51-59
• /
• 2010

People evaluate urban residential regions quite frequently and sensitively, considering issues such as locations or ease of use of in-site facilities or nearby urban facilities, and those results are bound to be reflected to real estate costs quite immediately. However, there have been frequently recurring questions regarding objectivity of evaluations in terms of results and methods reflected on indexes such as land costs for various reasons. RPMS -Residence Performance Management System- which targets currently in most cases on urban residential areas, suggests instrumental methodology of objective approach toward sensitive urban residence performance evaluation. This paper explains and suggests instrumental utilization of RPMS and its implementations, evaluation methodology and quantitative way of evaluation. In terms of implementation we explain issues such as adding target locations into new residence planning sites, quantification of properties on evaluation indexes of residential performance and/or habitability in terms of checklists, formulas for evaluation, delicate adjustment of evaluation results by setting weights on evaluation indexes, as well as reports on results. Research on appropriate weights and weight settings regarding evaluation indexes, however, exceeds the range of this paper so that this paper focuses on explaining residence performance evaluation and management methodology.

• 한국환경복원기술학회지
• /
• 제23권5호
• /
• pp.1-14
• /
• 2020

In order to improve the urban thermal environment, efforts are being made to increase green areas in cities that include park construction, planting, and green roofing. Among these efforts, urban parks play an important role not only in improving the urban thermal environment, but also in terms of ecosystem services (serving as resting places for citizens, providing cleaner air quality, reducing noise, etc.). Therefore, the purpose of this study is to suggest planning and management guidelines for urban parks that are effective in improving the thermal environment, by analyzing the urban surface temperature reduction performance of urban parks. To do this, first, land surface temperature was calculated by using Landsat 8 images. Second, the PCI (Park Cool Island) index was calculated to identify the temperature reduction performance of urban parks. Third, the characteristics of parks (area, shape, vegetation) and the surrounding spatial characteristics (land cover, building-related variables, etc.) were identified. Finally, the relationship between the PCI indices (PCI scale, PCI effect, PCI intensity) and the characteristics of the parks and their surroundings were analyzed. The results revealed that the parks consisting of a larger area, simple shape, and higher tree coverage ratio had increased PCI performance, and were advantageous for improving the urban thermal environment. Meanwhile, PCI performance was found to have decreased in areas with a higher impermeable area ratio and building coverage ratio. The outcomes of this study can be used to identify priority areas for planning and management of urban parks and can also be utilized as planning and management guidelines for improving urban thermal environment.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2004년도 추계학술대회 논문집
• /
• pp.157-161
• /
• 2004

Urban transit is system that offer target Performance and function because various lower part system such as vehicles, signaling, power supply, rail track is consisted as complex. It is important first of all that describe correctly system requirement until configuration of system, design, manufacture, installation and test verification so that the complicated urban transit system is to act safety and reliable and to display target Performance and function properly. The system requirement assist the system developer to comprehensive the performance and function of system in basic design. Therefore, In this paper wishes to study way to analyze system of system requirement and apply to Urban transit.