• Journal of KIISE:Databases
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• v.31 no.1
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• pp.39-47
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• 2004

Spatio-temporal databases have been mostly studied in the area of access methods. However, without considering an extraordinary update maintenance overhead after building up a spatio-temporal index, most indexing techniques have focused on fast query processing only. In this paper, we propose an efficient update management method that reduces the number of disk accesses required in order to apply the updates of moving objects to a spatio-temporal index. We consider realistic update patterns that can represent the movements of objects properly. We present a memory based structure that can efficiently maintain a small number of very frequently updating objects. For an experimental environment with realistic update patterns, the number of disk accesses of our method is about 40% lower than that of a general update method of existing spatio-temporal indexes.

• Journal of International Academy of Physical Therapy Research
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• v.6 no.2
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• pp.840-845
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• 2015

Improvement in functional gait is one of treatment goals in treatment of cerebral palsy children. This study intended to examine the effects of insoles for postural correction on gait in spastic cerebral palsy patients by investigating changes in gait temporal spatial parameters. As the subjects, 15 spastic bilateral cerebral palsy patients participated in this study. Temporal spatial parameters of gait were measured using GAITRite system under three gait conditions. Bare foot gait, gait in shoes, and gait in insoles for postural correction were conducted. In order to look at differences in temporal spatial parameters according to three gait conditions, repeated one way analysis of variance was conducted. As post hoc test, Bonferroni was conducted. A significant level was set at ${\alpha}=.05$. According to the result of this study, gait velocity, cadence, step length, stride length of the left lower extremity significantly changed. When the subjects put on customized insoles for postural correction, the effect was greatest. There were no significant changes in stance time, single support time, double support time, swing % of gait, and stance % of cycle. Therefore, gait with insoles for postural correction positively influenced functional gait improvement and will be able to be usefully employed for spastic cerebral palsy children as one of gait assistance devices.

• Journal of Environmental Science International
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• v.13 no.1
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• pp.27-36
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• 2004

Present study analyzed the temporal and spatial characteristics of PM10 pollution in Metropolitan Daegu area based on air pollution monitoring station data and measurements of PM10 concentrations in background area in order to provide essential data for efficient PM10 pollution management. The significant variation of spatial and temporal PM10 concentrations in Daegu area was observed during the study years. The highest maximum PM10 concentration(332 $\mu\textrm{g}$/㎥), average concentration(88 $\mu\textrm{g}$/㎥) and frequency exceeding PM10 daily standard(150 $\mu\textrm{g}$/㎥) were all observed in Namsandong located near a major roadway. The hourly and weekly variations of PM10 concentrations had different pattern for the measurement sites. The monthly and seasonal concentrations exhibited a notable characteristic： the maximum concentration was obtained in spring season, most likely due to Yellow sand effects. Furthermore, this temporal variation of PM10 pollution varied with study site. Meanwhile, the PM10 values measured at the monitoring site, Manchondong, were comparable with those of a control site. The average PM10 concentration ranged from 23 $\mu\textrm{g}$/㎥ to 115 $\mu\textrm{g}$/㎥ with a mean value of 53 $\mu\textrm{g}$/㎥ in the former site and from 22 $\mu\textrm{g}$/㎥ to 91 $\mu\textrm{g}$/㎥ with a mean value of 45 $\mu\textrm{g}$/㎥ in the latter site.

• Journal of Korea Spatial Information System Society
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• v.9 no.1
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• pp.59-77
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• 2007

Advances in mobile techknowledges and supporting techniques require an effective representation and analysis of moving objects. Similarity search of moving object trajectories is an active research area in data mining. In this paper, we propose a trajectory search algorithm for spatio-temporal similarity of moving objects on road network. For this, we define spatio-temporal distance between two trajectories of moving objects on road networks, and propose a new method to measure spatio-temporal similarity based on the real road network distance. In addition, we propose a similar trajectory search algorithm that retrieves spatio-temporal similar trajectories in the road network. The algorithm uses a signature file in order to retrieve candidate trajectories efficiently. Finally, we provide performance analysis to show the efficiency of the proposed algorithm.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.2
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• pp.76-84
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• 2017

This paper presents an efficient method for generating spatiotemporal images in order to detect leukocyte motion in microvessels. Leveraging the constraint that leukocytes move along the contour line of the blood vessel wall, our proposed method efficiently generates spatiotemporal images for leukocyte motion detection. To that end, translational motion caused by in vivo movement is first removed by a template matching method. Second, the blood vessel region is detected by an automatic threshold selection method in order to binarize temporal variance images. Then, the contour of the blood vessel wall is expressed via B-spline function. Finally, using the detected blood vessel wall's contour as an initial curve, the plasma layer for the most accurate position is determined in order to find the spatial axis via snake, and the spatiotemporal images are generated. Experimental results show that the spatiotemporal images are generated effectively through comparison of each step with three images.

• Korean Journal of Child Studies
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• v.19 no.2
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• pp.185-200
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• 1998

This research examined the development in Korean children of the comprehension of complex sentences. The relative difficulty in comprehension of the temporal conjunctions "before" and "after" was investigated. The order of mention, contextual support, and syntactic appearance was controlled. The role of cognitive strategies and developmental changes in the comprehension of these conjunction was included in this study. Subjects were 90 preschool children between 3 and 5 years of age. The task was a sentence-picture matching problem having 3 types of sentences combining temporally with "before" or "after". The results were that developmental changes in comprehension of the temporal conjunctions "before' and "after" in Korean children depended on the order of mention, contextual support, and such syntactic factors as the position of the subject of the sentence. The importance of the consistency in the occurrence of events and the order of mention in the acquisition of complex sentences among Korean children is similar to the acquisition of complex sentences in other languages.

• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.807-821
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• 2020

The objective of this study is to evaluate the applicability of representative spatio-temporal fusion models developed for the fusion of mid- and low-resolution satellite images in order to construct a set of time-series high-resolution images for crop monitoring. Particularly, the effects of the characteristics of input image pairs on the prediction performance are investigated by considering the principle of spatio-temporal fusion. An experiment on the fusion of multi-temporal Sentinel-2 and RapidEye images in agricultural fields was conducted to evaluate the prediction performance. Three representative fusion models, including Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM), SParse-representation-based SpatioTemporal reflectance Fusion Model (SPSTFM), and Flexible Spatiotemporal DAta Fusion (FSDAF), were applied to this comparative experiment. The three spatio-temporal fusion models exhibited different prediction performance in terms of prediction errors and spatial similarity. However, regardless of the model types, the correlation between coarse resolution images acquired on the pair dates and the prediction date was more significant than the difference between the pair dates and the prediction date to improve the prediction performance. In addition, using vegetation index as input for spatio-temporal fusion showed better prediction performance by alleviating error propagation problems, compared with using fused reflectance values in the calculation of vegetation index. These experimental results can be used as basic information for both the selection of optimal image pairs and input types, and the development of an advanced model in spatio-temporal fusion for crop monitoring.

• Journal of Korea Spatial Information System Society
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• v.8 no.2 s.17
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• pp.39-52
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• 2006

With the recent the use of spatio-temporal data mining which can extract various knowledge such as movement patterns of moving objects in history data of moving object gets increasing. However, the existing movement pattern extraction methods create lots of candidate movement patterns when the minimum support is low. Therefore, in this paper, we suggest the STMPE(Spatio-Temporal Movement Pattern Extraction) algorithm in order to efficiently extract movement patterns of moving objects from the large capacity of spatio-temporal data. The STMPE algorithm generalizes spatio-temporal and minimizes the use of memory. Because it produces and keeps short-term movement patterns, the frequency of database scan can be minimized. The STMPE algorithm shows more excellent performance than other movement pattern extraction algorithms with time information when the minimum support decreases, the number of moving objects increases, and the number of time division increases.

• Journal of Broadcast Engineering
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• v.18 no.5
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• pp.680-690
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• 2013

In this paper, we propose a real-time temporal synchronization and compensation algorithm in stereoscopic video. Many temporal asynchronies are caused in the video editing stage and due to different transmission delays. These temporal asynchronies can degrade the perceived 3D quality. The goal of temporal alignment is to detect and to measure the temporal asynchrony and recover synchronization of the two video streams. In order to recover synchronization of the two video streams, we developed a method to detect asynchronies between the left and the right video streams based on a novel spatiogram information, which is a richer representation, capturing not only the values of the pixels but their spatial relationships as well. The proposed novel spatiogram additionally includes the changes of the spatial color distribution. Furthermore, we propose a block-based method for detection of the pair frame instead of one frame-based method. Various 3D experiments demonstrate the effectiveness of the proposed method.

• The KIPS Transactions:PartD
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• v.9D no.4
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• pp.531-542
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• 2002

As most of metadata have been handled on restricted applications, we need a same metadata in order to represent a same video data. However, these metadata make problems that the same video data should be supported by the same metadata. Therefore, in this paper, we extend the Dublin core elements to support the metadata which can solve the problems. The proposed video data representation is managed by the extended metadata of Doblin core model, by using the information of structure, content and manipulation of video data. The thirteen temporal relationship operators are reduced to the six temporal relationship operators by using a dummy shot temporal transformation relationship. The reduced six temporal relationship operators through excluding reverse temporal relationship not only maintain a consistency of representation between a metadata and a video data, but also transform n-ary temporal relationship to binary relationship on shots. We show that the proposed metadata model can be applied to representing and retrieving on various applications as equivalent as the same structure.