• Journal of Information Technology Applications and Management
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• 제12권1호
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• pp.111-123
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• 2005

Many indexing methods were proposed so that process moving object efficiently. Among them, indexing methods like the 3D R-tree treat temporal and spatial domain as the same. Actually, however. both domain had better process separately because of difference in character and unit. Especially in this paper we deal with limited region such as indoor environment since spatial domain is limited but temporal domain is grown. In this paper we present a novel indexing structure, namely STS-tree(Separation of Time and Space tree). based on limited region. STS-tree is a hybrid tree structure which consists of R-tree and one-dimensional TB-tree. The R-tree component indexes static object and spatial information such as topography of the space. The TB-tree component indexes moving object and temporal information.

• 한국초전도ㆍ저온공학회논문지
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• 제17권4호
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• pp.34-37
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• 2015

Developing Magnetoencephalography (MEG) based on Superconducting Quantum Interference Device (SQUID) facilitates to observe the human brain functions in non-invasively and high temporal and high spatial resolution. By using this MEG, we studied alpha rhythm (8-13 Hz) that is one of the most predominant spontaneous rhythm in human brain. The 8-13 Hz rhythm is observed in several sensory region in the brain. In visual related region of occipital, we call to alpha rhythm, and auditory related region of temporal call to tau rhythm, sensorimotor related region of parietal call to mu rhythm. These rhythms are decreased in task related region and increased in task irrelevant regions. This means that these rhythms play a pivotal role of inhibition in task irrelevant region. It may be helpful to attention to the task. In several literature about the alpha-band inhibition in multi-sensory modality experiment, they observed this effect in the occipital and somatosensory region. In this study, we hypothesized that we can also observe the alpha-band inhibition in the auditory cortex, mediated by the tau rhythm. Before that, we first investigated the existence of the alpha and tau rhythm in occipital and temporal region, respectively. To see these rhythms, we applied the visual and auditory stimulation, in turns, suppressed in task relevant regions, respectively.

• 전자공학회논문지S
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• 제36S권11호
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• pp.54-59
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• 1999

본 논문에서는 보다 정확한 선형예측을 위해 시공간적응적 기반영역에 바탕을 둔 확장된 auto regressive(AR) 모델을 제안한다. 기존의 AR 모델에서 영상 전체에 걸쳐 사용되는 직사각형 형태의 기반영역은 영상의 경계선 영역에서는 더 이상 정상상태(stationarity)의 조건을 만족시키지 않음으로써 경계선 영역에서 예측오차가 증가하는 결점을 갖는다. 그래서 제안된 방법은 AR 모델에서 시공간적응적 기반영역이라 불리는 정상상태의 기반영역을 구성하는데 중점을 둔다. 시공간적응적 기반영역은 영상의 경계선 특성과 관련되는 공간적응적 기반영역과 시간축의 불연속 개념과 관련되는 시간적응적 기반영역으로 구성되어진다. 제안된 AR 모델은 동영상 복원 실험간 좀 더 정확한 모델 파라미터를 산출하였을 뿐만 아니라 복잡한 계산과정을 단순화하는 이점을 가진다.

• 한국수산과학회지
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• 제46권1호
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• pp.59-69
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• 2013

Temporal and spatial variation in the freshwater region, created by river runoff, of a small bay, caused by the passage of typhoons was examined using a three-dimensional primitive equation model (the Princeton Ocean Model, POM). Numerical experiments were implemented focusing on temporal evolution in the freshwater region in association with typhoon tracks. The model domain covered most of the estuary around the Nakdong River, including Noksan Bay, where river water is periodically released from upstream (Noksan dam). The model showed that the extension of the freshwater region outside of the bay depended strongly on the tracks of typhoons, specifically the associated wind directions and inner flow fields that are accompanied by new clockwise eddies. The model also showed that entrainment from typhoon passage frequently creates salt wedges in the estuary, indicating that organisms in the bay are biologically and chemically influenced with variation in the freshwater region.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.7-10
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• 2000

Fast block motion estimation technique is proposed to reduce the computational complexity in video coding. In the conventional methods the size of search region is fixed. For small motion regions like background the small size of sea of search region is enough to find a block motion. But for active motion regions the large size of search region is preferred to figure out the accurate motion vector. Therefore, it is reasonable that a block motion is estimated in the variable search region (both the size and the position of it). That is to say, the search region varies according to the predicted motion characteristics of a block. The block motion in video frames has temporal continuity and then the search region of a current block is predicted using the block motion of previous blocks. The computational complexity of the proposed technique is significantly reduced with a good picture quality compared to the conventional methods.

• 한국통신학회논문지
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• 제22권6호
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• pp.1195-1209
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• 1997

This paper presents a new morphological spatio-temporal segmentation algorithm. The algorithm incorporates luminance and motion information simultaneously, and uses morphological tools such as morphological filtersand watershed algorithm. The procedure toward complete segmentation consists of three steps:joint marker extraction, boundary decision, and motion-based region fusion. First, the joint marker extraction identifies the presence of homogeneours regions in both motion and luminance, where a simple joint marker extraction technique is proposed. Second, the spatio-temporal boundaries are decided by the watershed algorithm. For this purposek, a new joint similarity measure is proposed. Finally, an elimination ofredundant regions is done using motion-based region function. By incorporating spatial and temporal information simultaneously, we can obtain visually meaningful segmentation results. Simulation results demonstratesthe efficiency of the proposed method.

• 전기전자학회논문지
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• 제20권1호
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• pp.31-44
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• 2016

본 논문에서는 자유 시점 텔레비전에서 시점 합성 영상 획득을 위해 시공간적 배경 정보 추정 기반 홀 채움 방식을 제안한다. 신뢰할 수 있는 시간적 배경 정보를 획득하기 위해 새로운 배경 코드북의 구성 및 갱신하는 과정을 수행한다. 더불어, 공간적인 국부 배경 정보 추정을 위해 홀 영역의 배경 및 전경 영역의 구별 및 갱신 과정을 수행한다. 추정된 시공간 배경 정보를 조합하여 홀 채움 과정을 수행하고, 잔여 홀 채움을 수행하기 위해 깊이 배경 정보를 이용한 우선순위 함수를 결정하여 표본 기반 인페인팅 기법을 적용한다. 실험 결과를 통해 제안 방식은 기존방식들과 비교하여 평균 0.3~0.6dB의 성능 향상이 있음을 확인하였으며, 동영상 특성 및 홀 형태에 관계없이 제안된 방식이 새로운 시점 영상을 효과적으로 합성할 수 있음을 확인할 수 있었다.

• 대기
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• 제20권4호
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• pp.495-503
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• 2010

Satellite data have an intrinsic problem due to a number of various physical parameters, which can have a similar effect on measured radiance. Most evaluations of satellite performance have relied on comparisons with limited spatial and temporal resolution of ground-based measurements such as soundings and in-situ measurements. In order to overcome this problem, a new way of satellite data evaluation is suggested with statistical tools such as empirical orthogonal function(EOF), and singular value decomposition(SVD). The EOF analyses with OMI and OMI HCHO over northeast Asia show that the spatial pattern show high correlation with population density. This suggests that human activity is a major source of as well as HCHO over this region. However, this analysis is contradictory to the previous finding with GOME HCHO that biogenic activity is the main driving mechanism(Fu et al., 2007). To verify the source of HCHO over this region, we performed the EOF analyses with vegetation and HCHO distribution. The results showed no coherence in the spatial and temporal pattern between two factors. Rather, the additional SVD analysis between $NO_2$ and HCHO shows consistency in spatial and temporal coherence. This outcome suggests that the anthropogenic emission is the main source of HCHO over the region. We speculate that the previous study appears to be due to low temporal and spatial resolution of GOME measurements or uncertainty in model input data.

• 대한두개안면성형외과학회지
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• 제18권2호
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• pp.122-127
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• 2017

Castleman's disease (CD) is an uncommon benign lymphoproliferative disorder of unknown etiology. Histopathologically, it is divided into three types: hyaline-vascular, plasma cellular, and multicentric CD. The mass usually presents asymptomatically; however, it can cause non-specific symptoms such as fever and fatigue. Although CD can be found wherever lymph nodes are present, 75% of cases are reported in the mediastinum, and occurrence in the head and neck is rare. Herein, we report a rare case of CD presenting as a superficial mass in the temporal region. To the best of our knowledge, this is the first report of temporal CD in Korea involving a young patient.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제7권6호
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• pp.137-144
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• 2018

차량 애드혹 네트워크(VANETs)은 사고 통지, 콘텐츠 사용 등과 같은 다양한 응용프로그램을 제공할 수 있다. 이러한 응용 프로그램은 속성에 따라 관심영역과 수명을 갖는 시공간 데이터를 가지고 있다. 그러나, 관심 영역에 데이터를 전달하는 지오캐스팅 프로토콜은 현재 시간에만 단일 전송을 통해 영역의 모든 차량에 데이터를 제공할 수 있지만, 데이터의 수명시간 동안 해당 영역을 이동하는 차량에는 데이터를 제공할 수 없다. 따라서 우리는 VANET에서 데이터의 수명시간동안 관심 영역의 차량에 데이터를 전송하기 위해 지역적 캐싱 기법을 사용하는 시공간 지오캐스팅 프로토콜을 제안한다. 효율적이고 신뢰성 있는 지역적 캐싱을 위해서, 제안된 프로토콜은 비콘 기반 데이터 공유, 잔여 캐싱 제거 및 거리 기반 캐싱 교환을 사용한다. 시뮬레이션 결과는 제안된 프로토콜이 기존 프로토콜과 비교하여 보다 안정적이고 효율적인 데이터 전달을 달성하는지를 검증한다.