• Title/Summary/Keyword: Spatiotemporal

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A Spatiotemporal Location Prediction Method of Moving Objects Based on Path Data (이동 경로 데이터에 기반한 이동 객체의 시공간 위치 예측 기법)

  • Yoon, Tae-Bok;Park, Kyo-Hyun;Lee, Jee-Hyong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.16 no.5
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    • pp.568-574
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    • 2006
  • User adaptive services have been important features in many applications. To provide such services, various techniques with various kinds of data are being used. In this paper, we propose a method to analyze user's past moving paths and predict the goal position and the path to the goal by observing the user's current moving path. We develop a spatiotemporal similarity measure between paths. We choose a past path which is the most similar to the current path using the similarity. Based on the chosen path, user's spatiotemporal position is estimated. Through experiments we confirm this method is useful and effective.

Performance improvement of long-range underwater acoustic communication in deep water using spatiotemporal diversity (심해 장거리 환경에서 시공간 다이버시티를 이용한 수중음향통신성능 향상)

  • Park, Heejin;Kim, Donghyeon;Kim, J.S.;Hahn, Joo Young;Park, Joung-Soo
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.5
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    • pp.587-592
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    • 2019
  • ISI (Inter Symbol Interference) reduces the performance of UAComm (Underwater Acoustic Communication). This paper shows that the performance of UAComm can be improved through the spatiotemporal diversity method that is the combination of spatial diversity and temporal diversity methods. By using spatiotemporal diversity, the array aperture was reduced to increase the efficiency of the UAComm system. It is also verified using the experimental data of BLAC18 (Biomimetic Long range Acoustic Communication 18) conducted in October 2018.

Correlation between motor function and gait pattern of stroke patients (뇌졸중 환자의 운동기능과 보행 양상의 상관 관계)

  • Choi, Sanho;Lee, Ilsuk;Hong, Haejin;Oh, Jaegun;Sung, Kang-keyng;Lee, Sangkwan
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.14 no.1
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    • pp.8-14
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    • 2013
  • ■ Objectives The goal of this study is to find the correlation between the motor function and gait pattern of stroke patients. ■ Methods We measured Manual muscle test(MMT), Motricity index(MI) and Spatiotemporal gait parameters of admitted hemiplegic patients with stroke. The gait parameters were measured using a Treadmill gait system. ■ Results There is a significant correlation between motor function and spatiotemporal parameters such as step length, stride length, step time, stride time, total double support or cadence, in stroke patients. ■ Conclusion The better motor function of stroke was, the more gait improved.

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Correlation between Pediatric Balance Scale and Gait Parameter in Children with Spastic Diplegic Cerebral Palsy (경직성 양하지 뇌성마비 아동의 소아균형검사와 보행변수 간의 상관관계)

  • Ko, Myung-Sook;Park, So-Yeon;Lee, Nam-Gi
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.10 no.4
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    • pp.251-257
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    • 2016
  • The Pediatric Balance Scale (PBS) was balance measurement equipment for school-age children with mild to moderate motor impairments. The aims of this study are to examine the correlation between PBS and spatiotemporal gait parameter and to identify the walking function with cerebral palsy through balance scale. The PBS consists of 14 items such as sitting of standing, standing to sitting, transfers, standing unsupported, standing on one foot, turning 360 degrees, turing to look behind, etc., and the spatiotemporal parameters include walking speed, stride length, step length, step width, cadence, double-limb support. All subjects were independently ambulatory children with spastic diplegic cerebral palsy, and they were assessed on PBS and spatiotemporal gait parameters by an experienced pediatric physical therapist. Pearson's correlation coefficient was used to assess the correlation between PBS and spatiotemporal gait parameters, and the level of significance was set at ${\alpha}$ = 0.05. Total score of PBS(r=.49~.58), standing to sitting(r=.48~.60), turning to look behind(r=.47~.53), and pick up object(r=.52~.69) were positively correlated with walking speed, stride length, step length, and cadence. Most items of the PBS were negatively correlated with double-limb support(r=-.48~-.92). These findings suggest that the pediatric balance scale can be applied to estimate gait function level for children with spastic diplegic cerebral palsy.

Application of Satellite Data Spatiotemporal Fusion in Predicting Seasonal NDVI (위성영상 시공간 융합기법의 계절별 NDVI 예측에서의 응용)

  • Jin, Yihua;Zhu, Jingrong;Sung, Sunyong;Lee, Dong Kun
    • Korean Journal of Remote Sensing
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    • v.33 no.2
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    • pp.149-158
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    • 2017
  • Fine temporal and spatial resolution of image data are necessary to monitor the phenology of vegetation. However, there is no single sensor provides fine temporal and spatial resolution. For solve this limitation, researches on spatiotemporal data fusion methods are being conducted. Among them, FSDAF (Flexible spatiotemporal data fusion) can fuse each band in high accuracy.In thisstudy, we applied MODIS NDVI and Landsat NDVI to enhance time resolution of NDVI based on FSDAF algorithm. Then we proposed the possibility of utilization in vegetation phenology monitoring. As a result of FSDAF method, the predicted NDVI from January to December well reflect the seasonal characteristics of broadleaf forest, evergreen forest and farmland. The RMSE values between predicted NDVI and actual NDVI (Landsat NDVI) of August and October were 0.049 and 0.085, and the correlation coefficients were 0.765 and 0.642 respectively. Spatiotemporal data fusion method is a pixel-based fusion technique that can be applied to variousspatial resolution images, and expected to be applied to various vegetation-related studies.

Habitat Environments and Spatiotemporal Distribution of Clithon retropictum at the Estuaries of Bonggang and Miryoung Streams in the Southern Coast of Korea (남해안 봉강천과 미룡천 하구에서 기수갈고둥의 분포 및 서식지 환경 특성)

  • Jang, Keon Gang;Kim, Min-Seop;Jo, Soo-Gun;Yih, Wonho;Kim, Hyung Seop
    • Ocean and Polar Research
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    • v.43 no.3
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    • pp.127-140
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    • 2021
  • At the estuaries of Bonggang and Miryong streams in the Korean southern coast, the spatiotemporal distribution and habitat environment of a nerite snail, Clithon retropictum (Gastropoda: Neritidae), which has been assigned as a legally protected species of Korea, were explored. Physicochemical environmental factors such as water temperature, salinity, tidal level distribution as well as biotic environments (chlorophyll-a concentration and epilithic microalgae composition) were monitored every month. The relationships between the environmental factors and spatiotemporal distribution of the nerite snail population were analyzed. Water temperature, salinity, and water level varied by season and lunar tidal rhythm. The spatiotemporal distribution of the nerite snail was mostly related to water salinity. Among epilithic algae which were the priority prey of snails, blue-green algae and green algae dominated in summer and autumn, while diatoms predominated during winter and spring. Chlorophyll-a concentration was highly and positively correlated with the population density of the nerite snail. The correlation coefficients were different depending on the taxon (Family) of epilithic algae. The mean population density was 302.2 inds m-2 and 271.8 inds m-2 in Bonggang Stream and Miryong Stream, respectively. The egg capsules of the nerite snail in the two habitats were observed from March (in Bonggang Stream) or April (in Miryong Stream) to August, and newly hatched juveniles recruited in the habitats from August were assessed with regard to frequency distributions of shell width. The occurrence of large-sized snails in upper stream reaches of both Bonggang and Miryong indicated the movement of spats from the mouth to the upper reaches during the whole life cycle.

A New Covert Visual Attention System by Object-based Spatiotemporal Cues and Their Dynamic Fusioned Saliency Map (객체기반의 시공간 단서와 이들의 동적결합 된돌출맵에 의한 상향식 인공시각주의 시스템)

  • Cheoi, Kyungjoo
    • Journal of Korea Multimedia Society
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    • v.18 no.4
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    • pp.460-472
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    • 2015
  • Most of previous visual attention system finds attention regions based on saliency map which is combined by multiple extracted features. The differences of these systems are in the methods of feature extraction and combination. This paper presents a new system which has an improvement in feature extraction method of color and motion, and in weight decision method of spatial and temporal features. Our system dynamically extracts one color which has the strongest response among two opponent colors, and detects the moving objects not moving pixels. As a combination method of spatial and temporal feature, the proposed system sets the weight dynamically by each features' relative activities. Comparative results show that our suggested feature extraction and integration method improved the detection rate of attention region.