• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1027-1033
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• 2002

The solute transport in a two-dimensional heterogeneous porous medium is numerically studied by using a random walk particle tracking (RWPT) method. Lognormally isotropic hydraulic conductivity fields are generated by using the turning band methods with mean zero and four different values of standard deviation. The numerical transport experiments are carried out to investigate the large time and spatial effects of the variable pore velocity field on solute plumes. The behavior of the solute plume through numerical simulations is presented in terms of longitudinal and transverse spatial moments: displacement of center-of-mass, plume spread variance and skewness coefficient. It was observed that the dispersive behavior of the solute plume is strongly affected by the degree of heterogeneity in the flow domain.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.5
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• pp.343-350
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• 2019

Map labels are the most recognizable map elements using the human visual system because they are essentially a natural language. In this study, an experiment was conducted using an eye-tracker to objectively record and analyze the response of subjects regarding visual attention to map labels. A primary building object was identified by analyzing visit counts, average visit duration, fixation counts, and the average fixation duration of a subject's gaze for an area of interest acquired using the eye-tracker. The unmarked rate of map labels in Google map, Naver map, and Daum map was calculated. As a result, this rate exceeded fifty-one percent, with the lowest rate recorded for Google map. It is expected that the results of this study will contribute to an increase in the diversity of research in terms of the spatial cognition approach for map labels, which is more helpful to users than the existing body of work on methods of expression for labels.

• Wind and Structures
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• v.28 no.6
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• pp.347-354
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• 2019

This study provides an approximate analytical solution to the fractional vibration problem of thin plate governing anomalous motion of plate subjected to in-plane loads. The method of variable separable is employed to transform the fractional partial differential equations under consideration into a fractional ordinary differential equation in temporal variable and a bi-harmonic plate equation in spatial variable. The technique of conformable fractional derivative is utilized to solve the resulting fractional differential equation and the approach of finite sine integral transform method is used to solve the accompanying bi-harmonic plate equation. The deflection field which measures the transverse displacement of the plate is expressed in terms of product of Bessel and trigonometric functions via the temporal and spatial variables respectively. The obtained solution reduces to the solution of the free vibration problem of thin plate in literature. This work shows that conformable fractional derivative is an efficient mathematical tool for tracking analytical solution of fractional partial differential equation governing anomalous vibration of thin plates.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.09a
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• pp.7-9
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• 2010

이에 본 논문에서는 이동 객체의 위치를 향상 명시적으로 결정할 수 있는 추적 가능 실내 기호 공간(Trackable Indoor Symbolic Space)을 정의하고, 이러한 공간을 정의하기 위한 규칙들을 제안한다 위치를 좌표로 나타내는 실외 공간의 응용 프로그램들과는 달리, 대부분의 실내공간의 응용 프로그램들은 위치를 방 번호와 같은 기호적 값으로 표현하는 기호참조체계를 이용한다 이에, 본 논문에서는 실내기호공간의 개념과 실내 기호공간에서의 이동객체의 위치 추정에 대해 소개하고, 추정 가능한 실내공간을 만들기 위한 규칙과 방법을 제안하고 있다.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.228-230
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• 2009

The moment-of-fluid (MOF) method is a new volume-tracking method that accurately treats evolving material interfaces. Based on the moment data (volume and centroid) for each material, the material interfaces are reconstructed with second-order spatial accuracy in a strictly conservative manner. The MOF method is coupled with a stabilized finite element incompressible Navier-Stokes solver for two fluids, namely water and air. The effectiveness of the MOF method is demonstrated with a free-surface dam-break problem.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.173-179
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• 2003

Techniques to rapidly model local spaces, using 3D range data can enable implementation of: (1) real-time obstacle avoidance for improved safety, (2) advanced automated equipment control modes, and (3) as-built data acquisition for improved quantity tracking, engineering, and project control systems. The objective of the research reported here was to introduce current rapid local modeling techniques and develop rapid local spatial modeling tools.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2001.05a
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• pp.157-162
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• 2001

This Research analyzed with itinerary tracking : two of each other shopping sites were selected as research point. Analyzing the result, pedestrian path choice is affected by direction of escalator, visual information of the object, plain form of passage, presence and absence of companion and proportion of spatial knowledge from experience. The factors affecting pedestrian path choice are divided into two groups which are the effects from the environment, and personal characteristics.

• Journal of Broadcast Engineering
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• v.20 no.3
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• pp.449-463
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• 2015

Video object tracking is important for variety of applications, such as security, video indexing and retrieval, video surveillance, communication, and compression. This paper proposes an object tracking method in HEVC bitstreams. Without pixel reconstruction, motion vector (MV) and size of prediction unit in the bitstream are employed in an Spatio-Temporal Markov Random Fields (ST-MRF) model which represents the spatial and temporal aspects of the object's motion. Coefficient-based object shape adjustment is proposed to solve the over-segmentation and the error propagation problems caused in other methods. In the experimental results, the proposed method provides on average precision of 86.4%, recall of 79.8% and F-measure of 81.1%. The proposed method achieves an F-measure improvement of up to 9% for over-segmented results in the other method even though it provides only average F-measure improvement of 0.2% with respect to the other method. The total processing time is 5.4ms per frame, allowing the algorithm to be applied in real-time applications.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.5
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• pp.124-133
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• 2014

This study aims to track pedestrian behavior in urban linear tourist sites and to analyse their behavioral characteristics. For these purposes, this study has adopted the direct observation, a behavioral tracking methodology, and selected Chenggyecheon in Seoul as the study site, a representative site of urban regeneration. The main results of this study can be summarized as follows: the period of stay and movement distance of pedestrians in the study area are both short and most pedestrian activities, apart from walking, are of a passive nature, such as pitching pennies, reading signs, resting and the like. Spatial points of Chenggyecheon at which pedestrians have exhibited these behaviors during their stay are summarized as 30 points and classified into 3 types: landmarks, bridges and nodes. Further research that combines several tracking methods in terms of urban pedestrian behavior is needed.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.4
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• pp.211-222
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• 2020

This study suggested a method calculating the influence of effluent discharge from Saemangeum sluice-gates using the particle tracking model. For 2017, we presented the seasonal effects of effluent discharge as probability spatial distributions and compared with the results of the water age, one of the indicators of transport time scale. The influence of sluice-gates effluent discharge increases radially around Sinshi or Gaseok gates, which are expected to be biased toward the south in winter and north in summer due to the effect of seasonal winds. Although the results of the prediction are limited to the 2017 situation, the method of calculating the influence of sluice-gates effluent discharge using the Lagrangian particle tracking model can be used to predict the future of the around Saemangeum.