• Title/Summary/Keyword: spatial problem

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A Study on Circulation and Management of Spatial Data (공간정보 유통 및 관리에 관한 연구)

  • Cho, Hae-Gyung;Kim, Young-Sup;Kim, Sang-Eun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.1 no.1
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    • pp.28-38
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    • 1998
  • This paper describes difficulties for the producer's distribution and the user's acquisition of the spatial data because the circulation of them is complicated according to its kind in Korea. The way to overcome these difficulties would be to develop the clearing house system to incorporate GIS technology on Internet. This research proposes the problem statement, the architecture, and the operating environment of the system. The system contains the functions such as metadata generation, metadata registration, metadata version management, catalogue creation and update, reports generation, forms processing, metadata search, payments, GIS information pool, and spatial data browsing.

Gamma correction FCM algorithm with conditional spatial information for image segmentation

  • Liu, Yang;Chen, Haipeng;Shen, Xuanjing;Huang, Yongping
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.9
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    • pp.4336-4354
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    • 2018
  • Fuzzy C-means (FCM) algorithm is a most usually technique for medical image segmentation. But conventional FCM fails to perform well enough on magnetic resonance imaging (MRI) data with the noise and intensity inhomogeneity (IIH). In the paper, we propose a Gamma correction conditional FCM algorithm with spatial information (GcsFCM) to solve this problem. Firstly, the pre-processing, Gamma correction, is introduced to enhance the details of images. Secondly, the spatial information is introduced to reduce the effect of noise. Then we introduce the effective neighborhood mechanism into the local space information to improve the robustness for the noise and inhomogeneity. And the mechanism describes the degree of participation in generating local membership values and building clusters. Finally, the adjustment mechanism and the spatial information are combined into the weighted membership function. Experimental results on four image volumes with noise and IIH indicate that the proposed GcsFCM algorithm is more effective and robust to noise and IIH than the FCM, sFCM and csFCM algorithms.

A Missing Value Replacement Method for Agricultural Meteorological Data Using Bayesian Spatio-Temporal Model (농업기상 결측치 보정을 위한 통계적 시공간모형)

  • Park, Dain;Yoon, Sanghoo
    • Journal of Environmental Science International
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    • v.27 no.7
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    • pp.499-507
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    • 2018
  • Agricultural meteorological information is an important resource that affects farmers' income, food security, and agricultural conditions. Thus, such data are used in various fields that are responsible for planning, enforcing, and evaluating agricultural policies. The meteorological information obtained from automatic weather observation systems operated by rural development agencies contains missing values owing to temporary mechanical or communication deficiencies. It is known that missing values lead to reduction in the reliability and validity of the model. In this study, the hierarchical Bayesian spatio-temporal model suggests replacements for missing values because the meteorological information includes spatio-temporal correlation. The prior distribution is very important in the Bayesian approach. However, we found a problem where the spatial decay parameter was not converged through the trace plot. A suitable spatial decay parameter, estimated on the bias of root-mean-square error (RMSE), which was determined to be the difference between the predicted and observed values. The latitude, longitude, and altitude were considered as covariates. The estimated spatial decay parameters were 0.041 and 0.039, for the spatio-temporal model with latitude and longitude and for latitude, longitude, and altitude, respectively. The posterior distributions were stable after the spatial decay parameter was fixed. root mean square error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), and bias were calculated for model validation. Finally, the missing values were generated using the independent Gaussian process model.

A Video Expression Recognition Method Based on Multi-mode Convolution Neural Network and Multiplicative Feature Fusion

  • Ren, Qun
    • Journal of Information Processing Systems
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    • v.17 no.3
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    • pp.556-570
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    • 2021
  • The existing video expression recognition methods mainly focus on the spatial feature extraction of video expression images, but tend to ignore the dynamic features of video sequences. To solve this problem, a multi-mode convolution neural network method is proposed to effectively improve the performance of facial expression recognition in video. Firstly, OpenFace 2.0 is used to detect face images in video, and two deep convolution neural networks are used to extract spatiotemporal expression features. Furthermore, spatial convolution neural network is used to extract the spatial information features of each static expression image, and the dynamic information feature is extracted from the optical flow information of multiple expression images based on temporal convolution neural network. Then, the spatiotemporal features learned by the two deep convolution neural networks are fused by multiplication. Finally, the fused features are input into support vector machine to realize the facial expression classification. Experimental results show that the recognition accuracy of the proposed method can reach 64.57% and 60.89%, respectively on RML and Baum-ls datasets. It is better than that of other contrast methods.

A Study on the Introduction of the Rural Living Area of the RURITAGE Project Concept (RURITAGE 사업 개념의 농촌생활권 도입 방안)

  • Eom, Seong-Jun;Kim, Sang-Bum;An, Phil-Gyun
    • Journal of the Korean Institute of Rural Architecture
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    • v.23 no.4
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    • pp.46-54
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    • 2021
  • This study aimed to present a plan that introduces the concept of 'RURITAGE' into the 'Rural Convention' by analyzing the contents of the EU's 'RURITAGE' and the 'Rural Convention.' For this study, the contents and reports discussed on the 'RURITAGE' homepage were analyzed. Also, the applicability was reviewed by analyzing the 'Rural Convention' report and guideline. 'RURITAGE' was resources and heritage, currently possessed by the region rather than large-scale development. 'The Rural Convention' was intended to solve the problem of point-projects through mid-to-long-term planning, integrated support system for construction, and spatial analysis of rural spatial. It was also a policy to increase the satisfaction of the residents with the quality of life by guaranteeing a certain level of living services anywhere in the country. The 'Rural Spatial Strategic Plan' and 'Rural Living Area Revitalization Plan', included in 'the Rural Convention' are judged to be difficult to immediately introduce the concept of 'RURITAGE' due to the limitations of the projects that can implement projects. However, the notion of 'RURITAGE' can be reflected to 'Rural Spatial Maintenance Plan' seamlessly, which will be prepared in the 'Rural Living Area Revitalization Plan'.

Bias Correction of Satellite-Based Precipitation Using Convolutional Neural Network

  • Le, Xuan-Hien;Lee, Gi Ha
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.120-120
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    • 2020
  • Spatial precipitation data is one of the essential components in modeling hydrological problems. The estimation of these data has achieved significant achievements own to the recent advances in remote sensing technology. However, there are still gaps between the satellite-derived rainfall data and observed data due to the significant dependence of rainfall on spatial and temporal characteristics. An effective approach based on the Convolutional Neural Network (CNN) model to correct the satellite-derived rainfall data is proposed in this study. The Mekong River basin, one of the largest river system in the world, was selected as a case study. The two gridded precipitation data sets with a spatial resolution of 0.25 degrees used in the CNN model are APHRODITE (Asian Precipitation - Highly-Resolved Observational Data Integration Towards Evaluation) and PERSIANN-CDR (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks). In particular, PERSIANN-CDR data is exploited as satellite-based precipitation data and APHRODITE data is considered as observed rainfall data. In addition to developing a CNN model to correct the satellite-based rain data, another statistical method based on standard deviations for precipitation bias correction was also mentioned in this study. Estimated results indicate that the CNN model illustrates better performance both in spatial and temporal correlation when compared to the standard deviation method. The finding of this study indicated that the CNN model could produce reliable estimates for the gridded precipitation bias correction problem.

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Spatial Locality Preservation Metric for Constructing Histogram Sequences (히스토그램 시퀀스 구성을 위한 공간 지역성 보존 척도)

  • Lee, Jeonggon;Kim, Bum-Soo;Moon, Yang-Sae;Choi, Mi-Jung
    • Journal of Information Technology and Architecture
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    • v.10 no.1
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    • pp.79-91
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    • 2013
  • This paper proposes a systematic methodology that could be used to decide which one shows the best performance among space filling curves (SFCs) in applying lower-dimensional transformations to histogram sequences. A histogram sequence represents a time-series converted from an image by the given SFC. Due to the high-dimensionality nature, histogram sequences are very difficult to be stored and searched in their original form. To solve this problem, we generally use lower-dimensional transformations, which produce lower bounds among high dimensional sequences, but the tightness of those lower-bounds is highly affected by the types of SFC. In this paper, we attack a challenging problem of evaluating which SFC shows the better performance when we apply the lower-dimensional transformation to histogram sequences. For this, we first present a concept of spatial locality, which comes from an intuition of "if the entries are adjacent in a histogram sequence, their corresponding cells should also be adjacent in its original image." We also propose spatial locality preservation metric (slpm in short) that quantitatively evaluates spatial locality and present its formal computation method. We then evaluate five SFCs from the perspective of slpm and verify that this evaluation result concurs with the performance evaluation of lower-dimensional transformations in real image matching. Finally, we perform k-NN (k-nearest neighbors) search based on lower-dimensional transformations and validate accuracy of the proposed slpm by providing that the Hilbert-order with the highest slpm also shows the best performance in k-NN search.

A Study on a Conceptualization-oriented SDSS Model for Landscape Design (조경설계를 위한 공간개념화 지향의 공간의사결정지원시스템 모델에 대한 연구)

  • Kim, Eun Hyung
    • Spatial Information Research
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    • v.22 no.6
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    • pp.55-65
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    • 2014
  • By combining the role of current GIS technology and design behaviors from the cognitive perspective, spatial conceptualization can be extended efficiently and creatively for ill-structured problems. This study elaborates the model of a conceptualization-oriented SDSS(Spatial Decision Support System) for a landscape design problem. Current information-oriented GIS technology plays a minor role in planning and design. The three attributes in planning and design problems describe how the deficiencies of current GIS technology can be seen as a failure of the technology. These are summarized: (1) Information Explosion/Information Ignorance (2) Dilemma of Rigor and Relevance (3) Ill-structured Nature of planning and Design. In order to implement the conceptualization idea in the current GIS environment, it will be necessary to shift from traditional, information-oriented GISs to conceptualization-oriented SDSSs. The conceptualization-oriented SDSS model reflects the key elements of six important theories and techniques. The six useful theories and techniques are as follows; (1) Human Information Processing (2) Tool/Theory Interaction (3) The Sciences of the Artificial and Epistemology of Practice (4) Decision Support Systems (DSSs) (5) Human-Computer Interaction (HCI) (6) Creative Thinking. The future conceptualization-oriented SDSS can provide capabilities for planners and designers to figure out some "hidden organizations" in spatial planning and design, and develop new ideas through its conceptualization capability. The facilitation of conceptualization has been demonstrated by presenting three key ideas for the framework of the SDSS model: (1) bubble-oriented design support system (2) prototypes as an extension of semantic memory, and (3) scripts as an extension of episodic memory in a cognitive pschology perspective. The three ideas can provide a direction for the future GIS technology in planning and design.

A Study on Construction & Management of Urban Spatial Information Based on Digital Twin (디지털트윈 기반의 도시 공간정보 구축 및 관리에 관한 연구)

  • Lih, BongJoo
    • Journal of Cadastre & Land InformatiX
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    • v.53 no.1
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    • pp.47-63
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    • 2023
  • The Seoul Metropolitan Government is building and operating digital twin-based urban spatial information to solve various problems in the city and provide public services. Two essential factors to ensure the stable utilization of spatial information for the implementation of such a digital twin city are the latest and quality of the data. However, it is time-consuming and costly to maintain continuous updating of high-quality urban spatial information. To overcome this problem, we studied efficient urban spatial information construction technology and the operation, management, and update procedures of construction data. First, we demonstrated and applied automatic 3D building construction technology centered on point clouds using the latest hybrid sensors, confirmed that it is possible to automatically construct high-quality building models using high-density airborne lidar results, and established an efficient data management plan. By applying differentiated production methods by region, supporting detection of urban change areas through Seoul spatial feature identifiers, and producing international standard data by level, we strengthened the utilization of urban spatial information. We believe that this study can serve as a good precedent for local governments and related organizations that are considering activating urban spatial information based on digital twins, and we expect that discussions on the construction and management of spatial information as infrastructure information for city-level digital twin implementation will continue.

Spatial analysis of water shortage areas in South Korea considering spatial clustering characteristics (공간군집특성을 고려한 우리나라 물부족 핫스팟 지역 분석)

  • Lee, Dong Jin;Kim, Tae-Woong
    • Journal of Korea Water Resources Association
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    • v.57 no.2
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    • pp.87-97
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    • 2024
  • This study analyzed the water shortage hotspot areas in South Korea using spatial clustering analysis for water shortage estimates in 2030 of the Master Plans for National Water Management. To identify the water shortage cluster areas, we used water shortage data from the past maximum drought (about 50-year return period) and performed spatial clustering analysis using Local Moran's I and Getis-Ord Gi*. The areas subject to spatial clusters of water shortage were selected using the cluster map, and the spatial characteristics of water shortage areas were verified based on the p-value and the Moran scatter plot. The results indicated that one cluster (lower Imjin River (#1023) and neighbor) in the Han River basin and two clusters (Daejeongcheon (#2403) and neighbor, Gahwacheon (#2501) and neighbor) in the Nakdong River basin were found to be the hotspot for water shortage, whereas one cluster (lower Namhan River (#1007) and neighbor) in the Han River Basin and one cluster (Byeongseongcheon (#2006) and neighbor) in the Nakdong River basin were found to be the HL area, which means the specific area have high water shortage and neighbor have low water shortage. When analyzing spatial clustering by standard watershed unit, the entire spatial clustering area satisfied 100% of the statistical criteria leading to statistically significant results. The overall results indicated that spatial clustering analysis performed using standard watersheds can resolve the variable spatial unit problem to some extent, which results in the relatively increased accuracy of spatial analysis.