• 대한토목학회논문집
• /
• 제29권2D호
• /
• pp.267-273
• /
• 2009

대도시권의 공간구조 변화를 예측하고 문제를 미연에 방지하기 위해서는 도시공간구조의 시간적, 공간적 변화의 특성을 파악하는 것이 중요하다. 통근 통학 자료는 대도시권내에서 나타나는 필연적이며 규칙적인 통행에 대한 것으로 도시공간변화를 자세히 규명하는데 유용한 변수이며 최근 그 중요성이 높아지고 있다. 따라서 본 연구에서는 중력모델을 이용한 서울대 도시권 통근 통학자 자료 분석을 통해 서울시와 주변 도시 간 상호작용을 분석하였다. 그 결과, 서울과 주변 도시 간 상호 작용은 시간의 경과에 따라 강화되고 있음이 확인되었고, 도시 간 상호작용은 거리와 밀접한 연관을 갖는 것으로 검증되었으며, 서울과 강한 상호작용을 보이는 도시들이 대체로 서울 이남에 분포하고 있어 서울대도시권이 불균형적으로 개발되고 있음이 확인되었다.

• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.877-885
• /
• 2022

Vision-based activity recognition has been widely attempted at construction sites to estimate productivity and enhance workers' health and safety. Previous studies have focused on extracting an individual worker's postural information from sequential image frames for activity recognition. However, various trades of workers perform different tasks with similar postural patterns, which degrades the performance of activity recognition based on postural information. To this end, this research exploited a concept of human-object interaction, the interaction between a worker and their surrounding objects, considering the fact that trade workers interact with a specific object (e.g., working tools or construction materials) relevant to their trades. This research developed an approach to understand the context from sequential image frames based on four features: posture, object, spatial features, and temporal feature. Both posture and object features were used to analyze the interaction between the worker and the target object, and the other two features were used to detect movements from the entire region of image frames in both temporal and spatial domains. The developed approach used convolutional neural networks (CNN) for feature extractors and activity classifiers and long short-term memory (LSTM) was also used as an activity classifier. The developed approach provided an average accuracy of 85.96% for classifying 12 target construction tasks performed by two trades of workers, which was higher than two benchmark models. This experimental result indicated that integrating a concept of the human-object interaction offers great benefits in activity recognition when various trade workers coexist in a scene.

• 한국지진공학회논문집
• /
• 제7권3호
• /
• pp.57-67
• /
• 2003

Response analysis of buried pipeline subjected to permanent ground deformation(PGD) due to liquefaction is mainly executed by use of numerical analysis or semi-analytical relationship, When applying these methods, so called interfacial pipelineㆍsoil interaction force plays an dominant part. Currently used interaction force is mode up of indispensable mechanical and physical components for the response analysis of buried pipeline. However, it has somewhat limited applicability to the liquefied region since it is based on the experimental results for the non-liquefied region. Therefore, in this study, improved type of pipelineㆍsoil interaction force is proposed based on the existing interaction force and experimental research accomplishments. Above all, proposed interaction force includes various patterns of PGD or spatial distributions of interaction force caused by the decrease of soil stiffness. Through the comparison of numerical results using the proposed and the existing interaction force, relative influences of interaction force on the response of pipeline are evaluated and noticeable considerations in the application of semi-analytical relationship are discussed. Moreover, analyses due to the change of pipe thickness and burial depth are performed.

• Journal of Construction Engineering and Project Management
• /
• 제2권4호
• /
• pp.32-41
• /
• 2012

In recent times, multi-centralization and decentralization as well as large Capital area and suburbanization in the spatial structure of capital area. With rapid growth, urbanization and industrialization are unsystematic, and growth inequality between regions caused negative effects such as discordant centralization and decentralization, fluctuating land value, and gap between living conditions. Accordingly, this study analyzed urban spatial indexes by the self-governed body in the capital area such as Seoul, Incheon, and Gyeonggi province for the analysis of the regional inequality phenomenon. We examined the characteristics of temporal and spatial changes in urban spatial structure in the capital area by utilizing the distribution pattern and density of city indexes such as population, employment, etc, and then drew the commonality of those factors through factor analysis. We evaluated the drawn results through the city standard index by each city, conducted factor score analysis, and identified the interaction between each factor and Housing Purchase Price Composite Indices index, housing rent price index(Housing Jeonse Price Composite Indices), land price fluctuation rate, diffusion ratio of house, and financial independence.

• 국제초고층학회논문집
• /
• 제5권2호
• /
• pp.105-115
• /
• 2016

In the process of exploring sustainable development, major cities in China are expanding metro systems as a strategy to reduce the negative environmental and social consequences of fast-paced motorization. A metro station is not only a transportation node, but also a place where diverse activities can be performed. Therefore, the realization of the spatial potential for human interaction is the essence of the strategy for integrated development in metro station areas. For this paper, 10 well-developed metro stations in Central Shanghai were selected to investigate the correlation between accessibility and spatial performance in station areas. The spatial performance in station areas is significantly affected by metro configuration. However, both vehicle and pedestrian accessibility show weak influence on spatial performance. A synergistic model was then developed to provide quantitative support for transit-oriented development in metro station areas.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제6권3호
• /
• pp.578-597
• /
• 2014

Understanding of 'spatial' pressure distribution is required to determine design loads on local structures, such as plating and framing. However, obtaining a practical 'spatial' pressure distribution is a hard task due to the sensitivity of the data acquisition frequency and resolution. High-resolution Pessure-Idicating Flm (PIF) was applied to obtain pressure distribution and pressure magnitude using stepped crushing method. Different types of PIF were stacked at each test to creating a pressure distribution plot at specific time steps. Two different concepts of plotting 'spatial' pressure-area curve was introduced and evaluated. Diverse unit pixel size was chosen to investigate the effect of the resolution in data analysis. Activated area was not significantly affected by unit pixel size; however, total force was highly sensitive.

• 한국분무공학회지
• /
• 제16권4호
• /
• pp.195-200
• /
• 2011

The pressure-swirl atomizer is widely used for the injectors in liquid rocket engines thanks to its high performance atomization and broad stability margin range. Spray mixed-interaction is an important area of study especially in cases where the propellant is mixed by spray interaction after an oxidant and a fuel are discharged separately. This interaction of sprays results in a significant modification of the spray characteristics such as the spatial evolution of the sprays. Experiments are conducted by a photographic technique to quantify the merged angle of the interaction regions of sprays from two pressure-swirl injectors. The experimental results show that the merged angle is mainly determined by the momentum flux ratios between two swirled sprays.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 2003년도 춘계 학술발표회논문집
• /
• pp.165-173
• /
• 2003

In this study, the applicability of currently used pipeline.soil interaction force and previously proposed analytical relationship for the response analysis of buried pipeline subjected to transverse permanent ground deformation (PGD) due to liquefaction is evaluated. Based on meaningful contemplation, the improvement of interaction force and proposition of analytical relationship is made. Improved interaction force includes various patterns of PGD or spatial distributions of interaction force caused by the decrease of soil stiffness, and proposed relationship based on improved formula is applicable without regard to the width of PGD. Through the comparison of numerical results by use of commercial FEM program, the rational applicability of proposed relationship is objectively confirmed.

• 한국군사과학기술학회지
• /
• 제18권2호
• /
• pp.201-211
• /
• 2015

Acoustic propagation in shallow water with changing environments is a major concern of navy. Temporal and spatial variability of acoustic propagation in the northern East China Sea (ECS) is studied, using the 11 years hydrographic data and the Bellhop acoustic model. Acoustic propagation in the northern ECS is highly variable due to extensive interaction of various ocean currents and boundaries. Seasonal variations of transmission loss (TL) with various source depths are highly affected by sharp gradient of sound speed and bottoms interaction. Especially, various bottom sediment types lead to severely degrading a waterborne propagation with bottom loss. In particular, the highly increased TL near the ocean front depends on the source position, and the direction of sound propagation.

• 한국공간구조학회:학술대회논문집
• /
• 한국공간구조학회 2008년도 춘계 학술발표회 논문집
• /
• pp.212-217
• /
• 2008

본 논문은 앙골라 주경기장에 대한 구조설계에 대해 설명하고 있다. 앙골라 주경기장은 연면적 78,000$m^2$, 지상 4층 구조물로서 스탠드 부분은 Steel moment frame으로 구성되고, 지붕부분은 캔틸래버 트러스 시스템으로 설계되었다. 기초는 파일기초가 사용되었으며, 내진과 내풍설계, 스탠드 부분에 대한 다이아프램 액션, 스탠드와 지붕사이의 Interaction, 바닥진동 등 사용성 평가가 설계사항에 고려된 프로젝트이다.