• Journal of the Korean Geographical Society
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• v.40 no.2 s.107
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• pp.202-220
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• 2005

The substantial economic expansion of the 1990s with the dramatic changes in the provision of welfare services in America, including welfare services for the homeless, had unexpected and differential impacts on homelessness and poverty rates across the states. This paper examines a spatial pattern and process of homelessness by counties in Maryland, USA, considering the spatial differences in the composition of financial income and expenditure with sharply different poverty situation and welfare services. This social geographical approach of homelessness in Maryland focuses on the changing personal characteristics of homeless people and the relation=hip between homelessness and poverty; homelessness and the provision of welfare services such as shelter beds and emergency food providers. It makes a conclusion that there is an uneven sociospatial patterns of homelessness, relating to diverse poverty situation and provision of welfare services for the homeless by variable welfare policy among counties, Maryland.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.3
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• pp.249-257
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• 2006

The spatial distribution of design parameters greatly affects tunnel behavior during and after construction, as well as in the long-term temporal responses. However, the tunnel design parameters commonly used in numerical modeling tend to be representative or average values of global-scale properties. Furthermore, the uncertainty and spatial variation of the design parameters increase as the tunnel scale increases. Consequently, the probability of failure also increases. In order to achieve structural stability in large-section tunnels, the design framework must take into consideration the quantitative effect of design parameter variations on tunnel behavior. Therefore, this paper suggests a statistical approach to numerical modeling to explore the effect of spatially distributed design parameters in a circular tunnel. Also, the effect of spatial variation in the lining strength is studied in this paper. The numerical results suggest that the deformation around the tunnel increases with an increase in the variation of the design parameters.

• Geophysics and Geophysical Exploration
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• v.17 no.2
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• pp.88-94
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• 2014

Due to mechanical failure or geographical accessibility, the seismic data can be partially missed. In addition, it can be coarsely sampled such as crossline of the marine streamer data. This seismic data that irregular sampled and spatial aliased may cause problems during seismic data processing. Accurate and efficient interpolation method can solve this problem. Futhermore, interpolation can save the acquisition cost and time by reducing the number of shots and receivers. Among various interpolation methods, the Matching Pursuit method can be applied to any sampling type which is regular or irregular. However, in case of using sinusoidal basis function, this method has a limitation in spatial aliasing. Therefore, in this study, we have developed wavelet based Matching Pursuit method that uses wavelet instead of sinusoidal function for the improvement of dealiasing performance. In addition, we have improved interpolation speed by using inner product instead of L-2 norm.

• Journal of Korean Elementary Science Education
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• v.40 no.3
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• pp.390-406
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• 2021

This study investigated how elementary students with different spatial ability constructed spatial thinking process about on volcanoes and earthquakes with GeoMapApp-based materials. Students' spatial thinking process was analyzed in terms of spatial concept recognized, tools of spatial representation, and their spatial reasoning to construct topographic structure. The student group with high-scored spatial ability showed the spatial reasoning based on internal representation of building mental images through sectional division of horizontal distance, directly connected with spatial concept, or distorting spatial concept. The student group with low-scored spatial ability built the spatial reasoning directly connected with spatial concept instead of transforming into internal representation, and partially recognized spatial concept on either distance or depth. Based on the results, we argued identifying spatial concepts such as distance, height, or depth from the GeoMapApp data would be funda- mental for the better spatial thinking.

• Korean Journal of Cognitive Science
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• v.16 no.3
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• pp.155-174
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• 2005

Oh and Kim (2004) and Woodman and Lurk (2004) demonstrated that spatial working memory (SWM) load Interfered concurrent visual search and that search process also impaired the maintenance of spatial information implying that visual search and SWM task both require access to the same limited-capacity mechanism. Two obvious possibilities have been suggested about what this shared limited-capacity mechanism is: common demand for attention to the locations where the items f9r the two tasks were presented (spatial attention load hypothesis), and common use of working memory to maintain a record of locations have been processed(SWM load hypothesis). To test these two hypothetical explanations, Experiment 1 replicated the mutual interference between visual search and SWM task in spite of difference of procedure with preceding researches; possible areas where the items for two tasks were presented were not separated. In Experiment 2, we presented the items for visual search either in the same quadrants where the items for SWM task had appeared (same-location rendition) or in the different quadrants (different-location condition). As a result, search efficiency was more impaired in the different-location condition than in the same-location condition. The memory accuracy was worse in the different-location rendition than in the same-location rendition. Overall results of study indicate that the mutual interference between SWM and visual search might be related to the overload of spatial attention, but not to that of SWM.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2019.11a
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• pp.217-218
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• 2019

홀로그램을 재생하기 위한 SLM(Spaital Light Modulator)에서 홀로그램의 실수 정보 혹은 위상 정보를 사용한다. 본 논문에서는 홀로그램의 위상 정보를 효율적으로 압축하기 위한 방식을 제안한다. 홀로그램 압축 표준 코덱 개발에서는 표준 코덱을 기점으로 전후처리를 이용하여 압축효율의 개선 시키는 연구를 진행 중이다. 위상 정보는 -𝜋에서 +𝜋의 제한된 동적 범위를 가진다. 이는 위상 정보 사이의 공간적인 상관도를 낮추며 압축효율을 크게 떨어뜨리는 요인이 된다. 위상 펼침 기법을 이용하여 위상 정보 간의 공간적인 상관도를 확보한다. 공간적인 상관도가 확보된 위상 정보에 JPEG2000 표준 코덱의 입력을 고려하여 양자화한 뒤 압축 후 복원하고 효율을 분석한다.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.636-642
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• 2007

산업 전반에 적용되는 과학, 공학 분야에는 그 목적에 따라 다양한 형태의 정보가 발생한다. 정보는 이용하는 목적에 따란 가공하는 형식과 표현하는 방식이 달라지며, 정보에 직접적으로 접근하는 사용자에게 어떻게 효과적으로 전달할 것인가 하는 문제는 정보 관리 분야에서 매우 중요한 이슈가 되고 있다. 정보를 사용자에게 보다 명확하게 전달하고, 관리하기 위해서는 원천 데이터를 가공하여 가시화(visualization)하는 과정을 거친다. 정보가시화는 원천데이터를 데이터모델로 정리한 후, 가시화구조(visual structure)로 재정의 한다. 실질적인 가시적 결과는 가시화 구조의 데이터들을 정보모델(information model)상에 반영할 때 이루어진다. 본 논문에서는 건물내부에서 진행되는 행사에 대한 시간-공간적인 정보를 정리한 도표 메타포(table metaphor)를 초기 데이터 모델로 사용하여 가시화 하는 과정을 수행한다. 정보 가시화 과정과 저작 과정은 증강현실(augmented reality) 환경에서 이루어진다. 행사가 진행되는 장소의 건물 구조도(map)상에서 각 장소에서 발생하는 정보들을 재배열하고 정리함으로써, 저작자로 하여금 정보 그 자체에 대한 이해뿐만이 아니라, 해당 정보에 대한 공간적인 이해도 함께 가능하게 한다. 이 같은 몰입형(immersive) 저작시스템은 정보에 대한 공간적인 분배가 필요한 저작에서는 매우 유용하며, 저작하는 환경 자체가 가시화의 결과물이 되므로 정보 저작에 대한 가시적 이해를 최대화 시킬 수 있다.

• 한국데이터정보과학회:학술대회논문집
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• 2006.04a
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• pp.99-108
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• 2006

대형 할인점 매출 데이터는 G-CRM, 에어기어 마케팅(Area Marketing)에 활용하기 위해 고객의 구매정보와 위치정보를 포함한다. TM중부좌표로 이루어진 고객 위치정보를 이용하여 지점간의 거리를 구할 수 있다. 서로 다른 위치에서 통시에 측정된 자료들이 공간적인 변인에 의하여 영향을 받는다면, 공간적인 변인의 함수식에 의한 예측모형을 설정하는 것이 타당하다. 본 연구에서는 공간적인 변인으로 거리가 주어졌을 때, 대형 할인점 매출 자료에 대한 세미베리오그램(Semi-Variogram)의 모형을 추정하고, 관측되지 않은 지역에 대한 할인점 이용권을 공간예측기법으로 예측하였다. 그리고 공간예측 기법을 통해 예측된 할인점 이용권을 토대로 할인점 이용권 지도를 작성하였다. 또한 매출 데이터의 공간이상치 탐지를 위한 방법을 제시하고 실례로 알아보았다.

• Journal of the Korean Geographical Society
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• v.45 no.6
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• pp.820-844
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• 2010

This study investigates the effect of GIS-integrated lessons on spatial thinking abilities and geographical skills using discourse analysis along with a comparative three-case case study method. A series of curricula were designed and implemented in an 8th grade classroom for a semester. The data collected consist of the dialogue transcripts of six consecutive GIS-integrated lessons. The transcripts were analyzed to identify the moves (speech acts) used by each student and to classify discourse content of spatial thinking and geographical skills. Based on three individual case studies, a cross-case study was performed to uncover any relationship between the phenomenon and the contexts. The empirical evidence from discourse analysis demonstrated that students were able to generate appropriate terms representative of spatial thinking and geographical skills although students appeared to possess primarily lower-order spatial abilities, followed by a moderate-level of spatial abilities. Considering that the unit was implemented in a biology class rather than a geography class the result reflected the fact that the student's spatial thinking and geographical skills were attributable to the GIS-integrated lessons. Thus, the results have a great implication for GIS-integrated lessons and geography education as an innovative tool for improving student's spatial thinking and geographical skills.

• Spatial Information Research
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• v.18 no.1
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• pp.11-17
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• 2010

The present study attempts to provide the practical methodology to determine the spatial boundary of trade area, not depending on conventional circle-based regional analysis, but adopting dimension-diverging conception based on GIS and road connectivity by exemplifying a large-scale discount store with an outlook to enhance accuracy and reliability in trade area analyzing. Unlike the preliminary researches frequently relying on circular form of interpretation which were not likely to exclude obstacles blocking the accessibility to trade areas, the method suggested by the study is to suggest an alternative way for demarcating the trade areas more practically with better access by excluding in-between obstacles. Finally, we show verification of proposed cost models and performance by join strategy.