• Journal of Korea Society of Industrial Information Systems
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• v.28 no.6
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• pp.45-52
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• 2023

Recently, as the importance of walking in daily life has been emphasized, projects to guarantee walking rights and create a pedestrian environment are being promoted throughout the region. In previous studies, a pedestrian environment assessment was conducted using Jeonju-si road images, and an image comparison pair data set was constructed. However, data sets expressed in numbers have difficulty in generalizing the judgment criteria of pedestrian environment assessors or visually identifying the pedestrian environment preferred by pedestrians. Therefore, this study proposes a method to interpret the results of the pedestrian environment assessment through data visualization by building a web application. According to the semantic segmentation result of analyzing the walking environment components that affect pedestrian environment assessors, it was confirmed that pedestrians did not prefer environments with a lot of "earth" and "grass," and preferred environments with "signboards" and "sidewalks." The proposed study is expected to identify and analyze the results randomly selected by participants in the future pedestrian environment evaluation, and believed that more improved accuracy can be obtained by pre-processing the data purification process.

• Wind and Structures
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• v.9 no.6
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• pp.473-492
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• 2006

This paper presents numerical results of pedestrian-level wind environment around the base of a row of tall buildings by CFD. Four configurations of building arrangement are computed including a single square tall building. Computed results of pedestrian-level wind flow patterns and wind speeds are compared to previous wind tunnel measurement data to enable an assessment of CFD predictions. The CFD model uses the finite-volume method with RNG $k-{\varepsilon}$ model for turbulence closure. It is found that the numerical results can reproduce key features of pedestrian-level wind environment such as corner streams around corners of upwind building, sheltered zones behind buildings and channeled high-speed flow through a building gap. However, there are some differences between CFD results and wind tunnel data in the wind speed distribution and locations of highest wind speeds inside the corner streams. In locations of high ground-level wind speeds, CFD values match wind tunnel data within ${\pm}10%$.

• KIEAE Journal
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• v.16 no.3
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• pp.47-55
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• 2016

Purpose: This study was aimed at providing the basic checklist as a means to assess the crime risk in physical environment of the pedestrian passage at residential area. Method: For this purpose, the preliminary checklists were selected according to the review of the precedent studies of checklists in exterior pedestrian passage. The usefulness and the importance of the preliminary checklists were analyzed through the seven expert group meetings, the 87 questionnaires survey of the crime experts & the architectural/urban experts, preliminary assessment and field survey. Results: The assessment categories of checklists were sorted into six types, i.e. spatial structure & function, lighting, landscaping, security facilities, other facilities and cleaning & maintenance. The 49 checklists were proposed according to the assessment categories. The final checklists were divided key checklists and general checklists based on the results of experts' weighting of each list item. There were significant differences between crime experts' weighting and architectural/urban experts' weighting in several checklists, i.e. dividing between pavements and streets, the brightness of light, white light.

• Journal of Environmental Impact Assessment
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• v.26 no.4
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• pp.242-256
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• 2017

In this paper, dispersion scenarios concerning various meteorological conditions and real urban structures were made to estimate the impacts of hazardous substance leakage accidents and to reduce damages. Based on the scenario of the hazardous substance dispersion, the characteristics of the risk in the pedestrian environment were analyzed in Gangnam, Seoul. The scenarios are composed of 48 cases according to the meteorological conditions of wind direction and wind speed. In order to analyze the dispersion characteristics of the hazardous substances, simulations were conducted using a computational fluid dynamic (CFD) model with hydrogen fluoride releases. The validation for the simulated wind was conducted at a specific period, and all the calculated verification indices were within the valid range. As a result of simulated dispersion field at pedestrian level, it was found that the dispersion pattern was influenced by the flow, which was affected by the artificial obstacles. Also, in the case of the weakest wind speed of the inflow, the dispersion of the hazardous substance appeared in the direction of the windward side at the pedestrian level due to the reverse flow occurred at lower layers. Through this study, it can be seen that the artificial structures forming the city have a major impact on the flow formed in urban areas. The proposed approach can be used to simulate the dispersion of the hazardous substances and to assess the risk to pedestrians in the industrial complexes dealing with actual hazardous substances in the future.

• Wind and Structures
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• v.11 no.1
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• pp.51-70
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• 2008

CFD is applied to evaluate pedestrian wind comfort at outdoor platforms in a high-rise apartment building. Model validation is focused on generic building sub-configurations that are obtained by decomposition of the actual complex building geometry. The comfort study is performed during the design stage, which allows structural design changes to be made for wind comfort improvement. Preliminary simulations are performed to determine the effect of different design modifications. A full wind comfort assessment study is conducted for the final design. Structural remedial measures for this building, aimed at reducing pressure short-circuiting, appear to be successful in bringing the discomfort probability estimates down to acceptable levels. Finally, the importance of one of the main sources of uncertainty in this type of wind comfort studies is illustrated. It is shown that the uncertainty about the terrain roughness classification can strongly influence the outcome of wind comfort studies and can lead to wrong decisions. This problem is present to the same extent in both wind tunnel and CFD wind comfort studies when applying the same particular procedure for terrain relation contributions as used in this paper.

• Journal of Korean Society of Transportation
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• v.28 no.4
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• pp.141-156
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• 2010

In this paper, understanding there is a limitation with a comprehensive and network approach for the evaluation of existing vehicle and pedestrian environments, the authors focus on developing an integrated approach to assessing these environments. The network evaluation here means the assessment at a three-dimensional level that includes evaluation methods of lines/axes in a spatial concept as well as integration of evaluation indicators being used for vehicles and the walking environment. Grey System Theory (GST) was applied based on the theoretical background for network and comprehensive integrated evaluation, and the evaluation of the vehicle and pedestrian environment was performed by assigning target areas to walking preference zones. As a result of the comprehensive evaluation and analysis by GST, even if the service level is the same as the operating indicators (Highway Capacity Manual) of the vehicle and pedestrian environment, or relatively better, it was identified that the total score could be varied over Grey Category because the observed data are calculated after considering the weights between evaluation indicators by the range of Grey Category on the comprehensive evaluation. Considering comprehensively these points, although the indicators on the operation of roads are relatively good, in the event that the indicators on the safety of roads are bad, it was known that the scores over Grey Category also could be changed. The result is that this evaluation method can be used to evaluate the network concept per lane (per axis) as well as to diagnose the current state by type of urban street in the future.

• Journal of Drive and Control
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• v.19 no.4
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• pp.110-116
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• 2022

Recently, various studies have been conducted to apply deep learning and AI to various fields of autonomous driving, such as recognition, sensor processing, decision-making, and control. This paper proposes a controller applicable to path following, static obstacle avoidance, and pedestrian avoidance situations by utilizing reinforcement learning in autonomous vehicles. For repetitive driving simulation, a reinforcement learning environment was constructed using virtual environments. After learning path following scenarios, we compared control performance with Pure-Pursuit controllers and Stanley controllers, which are widely used due to their good performance and simplicity. Based on the test case of the KNCAP test and assessment protocol, autonomous emergency steering scenarios and autonomous emergency braking scenarios were created and used for learning. Experimental results from zero collisions demonstrated that the reinforcement learning controller was successful in the stationary obstacle avoidance scenario and pedestrian collision scenario under a given condition.

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.117-122
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• 2019

City parks play an important role in reducing the air pollution and mitigating the city heat island effect caused by global warming. However, from July 2020, restricted parks over 20-year will be partially lifted due to sunset regulation on parks. As a result, the government and local governments have been making efforts to revitalize parks, such as creating ecological parks and securing park sites. However, building winds generated by high-rise buildings constructed around ecological parks in the city may cause discomfort to pedestrians and threaten the ecosystems of plants and animal that live in ecological parks. There are no clearly proposed as standards for wind environment assessment in Korea, but also it has been rarely studied on pedestrian wind environment. In this study, wind environment studies have been reviewed to find the important parameters related to wind environment assessment. Further, wind climate analysis using wind data obtained by Seoul meterological station was performed to examine the possibility of applicability of the wind environment assessment on the city ecological parks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.931-938
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• 2014

This study presents a systematic method of evaluation with the premise that satisfaction rating scale of the walking environment will vary according to the characteristics of land use by footpath types. Ultimately, it aims to contribute to the effective management and improvement of footpaths. The result of the study shows a statistically significant difference in the indicators and it's weights for walking environment on new town, old town, commercial areas, subway station, river and park by footpath types. After applying the walking environment assessment model to some of the footpaths in Suwon, it was found that actual level can be simulated successfully in reality. Therefore, the result of the study is expected to help determining the priorities for the walking environment improvement for the local government.

• The Journal of Sustainable Design and Educational Environment Research
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• v.14 no.2
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• pp.26-36
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• 2015

The new town was assumed that there is a difference between the country's elementary school environment. First, given the important elements of the school safety plan in order to verify this, and we plan to set up each of these elements by safety criteria. In the second chapter in order to achieve the objective of this study was to develop indicators to evaluate the safety of the school environment influences the safety of the school environment through the theoretical consideration. In Chapter 3, the difference in safety through the new elementary school survey of metropolitan areas was given a score per item per item depending on the evaluation criteria. The fourth section is the difference between safety school environment can be summarized as the following analytical results that the difference between the new city. The results of this study as follows: First, the characteristics of the elementary school environment showed a significant difference between the new town. Second, school location, terrain characteristics, bike paths and pedestrian to the installation, the safety of landscape installations, installing median barriers, traffic safety facilities, speed bumps, separation of pedestrian and vehicle circulation in the front door, scores of elements of the plan such as parking scheme there is a difference between the new town. Third, the introduction of elements of the plan such as Traffic calming or Traffic Island installation techniques was found lacking.