• 제목/요약/키워드: Spatiotemporal

검색결과 603건 처리시간 0.024초

Traffic Flow Prediction with Spatio-Temporal Information Fusion using Graph Neural Networks

  • Huijuan Ding;Giseop Noh
    • International journal of advanced smart convergence
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    • 제12권4호
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    • pp.88-97
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    • 2023
  • Traffic flow prediction is of great significance in urban planning and traffic management. As the complexity of urban traffic increases, existing prediction methods still face challenges, especially for the fusion of spatiotemporal information and the capture of long-term dependencies. This study aims to use the fusion model of graph neural network to solve the spatio-temporal information fusion problem in traffic flow prediction. We propose a new deep learning model Spatio-Temporal Information Fusion using Graph Neural Networks (STFGNN). We use GCN module, TCN module and LSTM module alternately to carry out spatiotemporal information fusion. GCN and multi-core TCN capture the temporal and spatial dependencies of traffic flow respectively, and LSTM connects multiple fusion modules to carry out spatiotemporal information fusion. In the experimental evaluation of real traffic flow data, STFGNN showed better performance than other models.

시계열적 공간통계 기법을 활용한 공시지가의 만족도 분석에 관한 연구 (A Study on the Satisfaction Analysis on Officially Assessed Land Price Using Time Seriate Geostatistical Analysis)

  • 최병길;나영우;현창섭;조태인
    • 한국측량학회지
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    • 제36권2호
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    • pp.95-104
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    • 2018
  • 이 연구는 공간통계 기법을 이용하여 공시지가에 대한 만족도를 시계열적으로 분석하기 위한 방법을 제시하는데 목적이 있다. 현재 GIS를 이용한 공시지가의 공간적 분포특성을 분석하거나, 공시지가 제도의 개선 방안을 정성적으로 제시하는데 머무르고 있다. 공시지가의 공시가격, 의견가격을 기준으로 이의신청 제기 강도를 그룹화 하여 공시지가에 대한 만족도 GIS DB를 구축하고, 공간밀도분석과 공간 자기상관분석을 통해서 만족도의 시계열적 변화를 비교 분석하였다. 연구 결과 공시가격과 의견가격과의 차이는 개별토지에 따라 다르나 대부분 평균 3배 이하의 상향 또는 하향을 요구하고 있는 것을 알 수 있었으며, 이를 통해 민원인들의 의견가격의 요구를 통계적으로 분석함으로써 민원인의 공시지가에 대한 만족도를 정량적으로 나타낼 수 있음을 알 수 있었다. 공시지가의 만족도를 GIS를 이용하여 분석함으로써 공시지가만이 아닌 의견가격과의 차이를 이용하여 공시지가의 만족도를 분석할 수 있음을 알 수 있었다. 공간 자기상관 분석 및 핫스팟 분석 등의 시계열적 공간통계분석 방법을 통해 공시지가 만족도의 시공간적 변화를 분석할 수 있음을 알 수 있었다. 즉, 연도별 자료를 활용한 시공간 분석을 통하여 지역적으로 양 또는 음의 유의적 관계를 규명할 수 있었다.

시간과 공간의 관념론적 접근을 통한 초현실주의적 디자인에 관한 연구 (A Study on Surrealistic Design by Apporaches to Spatiotemporal Idealism)

  • 김정아
    • 한국실내디자인학회논문집
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    • 제13권1호
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    • pp.46-53
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    • 2004
  • This study has importance of that it verifies applicability of a new interpretation of surrealism to spatial design. Transcendental cognitive form of idealism, concept of time and space are premise of reality and surreality is finally condensed to the matter of time and space. Surrealistic techniques are automatic description, double association, montage and etc, and all of them are trials to approach to essence of images expressing unconsciousness through spatiotemporal changes of object. The purpose of this study is to find the surrealistic methods that can be applied to spatial design.

Observation of the Spatiotemporal Variation of Wall Charge Distribution during Reset Period in an ac POP cell

  • Jeong, Dong-Cheol;Whang, Ki-Woong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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    • pp.756-759
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    • 2003
  • We measure the spatiotemporal wall charge distributions on sustain and address electrodes during reset period in an ac PDP cell using the longitudinal electro-optic amplitude modulation method. We apply several reset waveforms like as ramp, exponentially growing and high voltage pulse, and compare the wall charge characteristics on address electrode as well as sustain electrodes for each reset waveforms.

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BIFURCATION ANALYSIS OF A SINGLE SPECIES REACTION-DIFFUSION MODEL WITH NONLOCAL DELAY

  • Zhou, Jun
    • 대한수학회지
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    • 제57권1호
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    • pp.249-281
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    • 2020
  • A reaction-diffusion model with spatiotemporal delay modeling the dynamical behavior of a single species is investigated. The parameter regions for the local stability, global stability and instability of the unique positive constant steady state solution are derived. The conditions of the occurrence of Turing (diffusion-driven) instability are obtained. The existence of time-periodic solutions, the existence and nonexistence of nonconstant positive steady state solutions are proved by bifurcation method and energy method. Numerical simulations are presented to verify and illustrate the theoretical results.

Background Initialization by Spatiotemporal Similarity

  • 박구만
    • 방송공학회논문지
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    • 제12권3호
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    • pp.289-292
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    • 2007
  • A background initialization algorithm based on the spatiotemporal similarity measure in a motion tracking system is proposed. From the accumulated difference between the base frame and the other frames in a subinterval, the regions affected by moving objects are located. The median is applied over the subsequence in the subinterval in which co-located regions share the similarity. The outputs from each subinterval are filtered by second stage median filter. The proposed method showed good results even in the busy and crowded sequences where the real background does not exit.

만성 편마비 환자의 발목에 적용한 능동운동을 동반한 관절가동술이 하지근력과 보행의 시공간적 변수에 미치는 영향 (Effects of Ankle Joint Mobilization With Movement on Lower Extremity Muscle Strength and Spatiotemporal Gait Parameters in Chronic Hemiplegic Patients)

  • 안창만;원종임
    • 한국전문물리치료학회지
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    • 제19권3호
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    • pp.20-30
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    • 2012
  • The purpose of this study was to determine the effect of ankle joint mobilization with movement (MWM) on the range of motion (ROM) in the ankle, on the muscle strength of lower extremities, and on spatiotemporal gait parameters in chronic hemiplegic patients. Fifteen subjects with chronic stroke were divided into two groups: an experimental group (8 subjects) and a control group (7 subjects). Both groups attended two or three sessions of physical therapy each week. The experimental group also attended additional MWM training sessions three times a week for five weeks. For both groups, the ROM of the ankle, the muscle strength of the lower extremities, and the spatiotemporal gait parameters in paretic limbs were evaluated before and after the training period. The results showed that the experimental group experienced more significant increases than did the control group in terms of passive (6.10%) and active (21.96%) ROM of the ankle, gait velocity (12.96%), and peak torque, of the knee flexor (81.39%), the knee extensor (24.88%), and the ankle plantar flexor (41.75%)(p<.05). These results suggest that MWM training in patients with chronic stroke may be beneficial in increasing ROM in the ankle, muscle strength in the lower extremities, and gait speed.

체성감각 훈련이 뇌졸중 환자의 시공간적 보행요소 및 균형에 미치는 효과 (The Effects of Somatosensory Training on the Spatiotemporal Gait Parameters and Balance in Patients with Stroke)

  • 채정병;이문환
    • 대한물리의학회지
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    • 제5권4호
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    • pp.587-596
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    • 2010
  • Purpose : This study was performed to investigate the effects of somatosensory training on the spatiotemporal gait parameters and balance in patients with stroke patients. Methods : 24 stroke survivors were allocated in this study, and randomly divided into experimental(n=12) and control group(n=12), independently. Experimental group was applied somatosensory training program plus conventional physical therapy, and control group was applied only conventional physical therapy. All subjects were administered for 30 minutes per day during 8 weeks(5 times a week). Results : Spatiotemporal parameters of gait were significant difference between pre and post intervention in experimental group, except of step length asymmetry ratio(SLAR) and single support time asymmetry ratio (SSAR)(p<.05). But control group had no statistical significance(p>.05). And also there was significant difference between experimental and control group(p<.05), except of cadence and SSAR(p>.05). Balance parameters were significant difference between pre and post intervention in experimental group(p<.05). But control group had no statistical significance(p>.05). And experimental timed up and go test was significantly decreased than control group(p<.05), but berg balance scale and functional reach test were not significant difference between experimental and control group(p>.05). Conclusion : This study was suggested that somatosensory training has effectiveness on the spatiotemporal gait parameters and balance in patients with stroke survivors. So this therapeutic intervention will be effectivelyapply to the stroke survivors in the clinical setting.

Spatiotemporal Analysis of Hippocampal Long Term Potentiation Using Independent Component Analysis

  • Kim, T.S.;Lee, J.J.;Hwang, S.J.;Lee, Y.K.;Park, J.H.
    • 대한의용생체공학회:의공학회지
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    • 제28권1호
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    • pp.17-23
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    • 2007
  • Long-term potentiation (LTP) of synaptic transmission is the most widely studied model for learning and memory. However its mechanisms are not clearly elucidated and are a subject for intense investigation. Previous attempts to decipher cellular mechanisms and network properties involved a current-source density analysis (CSDA) of the LTP from small animal hippocampus measured with a limited number of microelectrodes (typically <3), only revealing limited nature of spatiotemporal dynamics. Recent advancement in multi-electrode array (MEA) technology allows continuous and simultaneous recordings of LTP with more than 60 electrodes. However CSDA via the standard Laplacian transform is still limited due to its relatively high sensitivity toward noise, inability of resolving overlapped current sources and sinks, and its requirement for tissue conductivity values. In this study, we propose a new methodology for improved CSDA. Independent component analysis and its joint use (i.e., Joint-ICA) are applied to extract spatiotemporal components of LTP. The results show that ICA and Joint-ICA are capable of extracting independent spatiotemporal components of LTP generators. The ICs of LTP indicate the reversing roles of current sources and sinks which are associated with LTP.

추출 연산을 활용한 이동 점 객체 색인 기법 (An Indexing Technique of Moving Point Objects using Projection)

  • 정영진;장승연;안윤애;류근호
    • 한국정보과학회논문지:데이타베이스
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    • 제30권1호
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    • pp.52-63
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    • 2003
  • 현실 세계에서 시간에 따라 연속적으로 위치나 모양이 변하며 이동하는 데이타를 시공간 이동 객체라 한다. 기존의 이동 객체 색인은 R-트리의 구조를 가지기 때문에, dead spare, overlap 등 R-트리의 문제점을 그대로 갖고 있을 뿐만 아니라 고려하는 초점에 따라 이 문제가 더 커진다. 따라서, 이 논문에서는 이 문제점을 해결하기 위하여 MPR-트리(Moving Point R-tree)를 제안한다. 제안된 MPR-트리는 추출 연산을 활용하여 특정 시점 질의 및 시공간 범위 질의를 효과적으로 처리하며, 동일한 이동 객체 위치를 시간에 따라 연결리스트로 연결하여 궤적 질의 처리를 용이하게 처리한다. 기존 이동 객체 색인과 비교한 실험으로부터 이동 객체 질의 처리 및 공간 활용에 대해 추출 연산이 유용하게 산임을 확인하였다. 제안된 MPR-트리는 LBS, GPS를 활용한 차량 관리 시스템, 항법 시스템 등 이동 객체 관리를 위한 시스템에서 활용될 수 있다.