• Title/Summary/Keyword: Data Generalization

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Time Series Prediction Using a Multi-layer Neural Network with Low Pass Filter Characteristics (저주파 필터 특성을 갖는 다층 구조 신경망을 이용한 시계열 데이터 예측)

  • Min-Ho Lee
    • Journal of Advanced Marine Engineering and Technology
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    • v.21 no.1
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    • pp.66-70
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    • 1997
  • In this paper a new learning algorithm for curvature smoothing and improved generalization for multi-layer neural networks is proposed. To enhance the generalization ability a constraint term of hidden neuron activations is added to the conventional output error, which gives the curvature smoothing characteristics to multi-layer neural networks. When the total cost consisted of the output error and hidden error is minimized by gradient-descent methods, the additional descent term gives not only the Hebbian learning but also the synaptic weight decay. Therefore it incorporates error back-propagation, Hebbian, and weight decay, and additional computational requirements to the standard error back-propagation is negligible. From the computer simulation of the time series prediction with Santafe competition data it is shown that the proposed learning algorithm gives much better generalization performance.

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Line Segmentation Method using Expansible Moving Window for Cartographic Linear Features (확장형 이동창을 이용한 지도 선형 개체의 분할 기법 연구)

  • Park, Woo-Jin;Lee, Jae-Eun;Yu, Ki-Yun
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.5-6
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    • 2010
  • Needs for the methodology of segmentation of linear feature according to the shape characteristics of line feature are increasing in cartographic linear generalization. In this study, the line segmentation method using expansible moving window is presented. This method analyzes the generalization effect of line simplification algorithms depend on the line characters of linear feature and extracts the sections which show exclusively low positional error due to a specific algorithm. The description measurements of these segments are calculated and the target line data are segmented based on the measurements. For segmenting the linear feature to a homogeneous section, expansible moving window is applied. This segmentation method is expected to be used in the cartographic map generalization considering the shape characteristics of linear feature.

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Study on the Filtering Methods for Mobile Vector Map Service (모바일 벡터 맵 서비스를 위한 필터링 기법 연구)

  • Choi Jin-Ho;Lee Sang-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.9
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    • pp.1612-1616
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    • 2006
  • For map services in the mobile environment, it should be considered that resource restriction or the mobile device. on, if a map database dedicated to mobile services may not be developed, the spatial data extracted from general map databases should be simplified before transmitting. % is paper suggests the filtering methods to manipulate the spatial data, which are changed to be able to displayed on the mobile devices. The suggested methods are evaluated by experiments. This method is based on the map generalization operator 'selection' and is refined to adapt on mobile phone environments.

Improving Generalization Performance of Neural Networks using Natural Pruning and Bayesian Selection (자연 프루닝과 베이시안 선택에 의한 신경회로망 일반화 성능 향상)

  • 이현진;박혜영;이일병
    • Journal of KIISE:Software and Applications
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    • v.30 no.3_4
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    • pp.326-338
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    • 2003
  • The objective of a neural network design and model selection is to construct an optimal network with a good generalization performance. However, training data include noises, and the number of training data is not sufficient, which results in the difference between the true probability distribution and the empirical one. The difference makes the teaming parameters to over-fit only to training data and to deviate from the true distribution of data, which is called the overfitting phenomenon. The overfilled neural network shows good approximations for the training data, but gives bad predictions to untrained new data. As the complexity of the neural network increases, this overfitting phenomenon also becomes more severe. In this paper, by taking statistical viewpoint, we proposed an integrative process for neural network design and model selection method in order to improve generalization performance. At first, by using the natural gradient learning with adaptive regularization, we try to obtain optimal parameters that are not overfilled to training data with fast convergence. By adopting the natural pruning to the obtained optimal parameters, we generate several candidates of network model with different sizes. Finally, we select an optimal model among candidate models based on the Bayesian Information Criteria. Through the computer simulation on benchmark problems, we confirm the generalization and structure optimization performance of the proposed integrative process of teaming and model selection.

Data Mining mechanism using Data Cube and Neural Network in distributed environment (분산환경에서 데이터 큐브와 신경망을 이용한 데이터마이닝기법)

  • 박민기;바비제라도;이재완
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.188-191
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    • 2003
  • In this paper, we proposed data generalization and data cube mechanism for efficient data mining in distribute environment. We also proposed active Self Organization Map applying traditional Self Organization Map of Neural network for searching the most Informative data created from data cube after the generalization procedure and designed the system architecture for that.

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A Pruning Algorithm of Neural Networks Using Impact Factors (임팩트 팩터를 이용한 신경 회로망의 연결 소거 알고리즘)

  • 이하준;정승범;박철훈
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.41 no.2
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    • pp.77-86
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    • 2004
  • In general, small-sized neural networks, even though they show good generalization performance, tend to fail to team the training data within a given error bound, whereas large-sized ones learn the training data easily but yield poor generalization. Therefore, a way of achieving good generalization is to find the smallest network that can learn the data, called the optimal-sized neural network. This paper proposes a new scheme for network pruning with ‘impact factor’ which is defined as a multiplication of the variance of a neuron output and the square of its outgoing weight. Simulation results of function approximation problems show that the proposed method is effective in regression.

A Study on Spatial Data Simplification Methods for Mobile GIS (모바일 GIS를 위한 공간 데이터 간소화 기법에 대한 연구)

  • 최진오
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.1
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    • pp.150-157
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    • 2004
  • For the mobile GIS services, it is not acceptable to construct a new map database only for wireless service due to vast cost. But the existing map database cannot be used directly for the services due to narrow wireless bandwidth and shortage of mobile device resources. This thesis proposes spatial data simplification methods, thus, the existing map database enable the mobile GIS services. The proposing methods are based on the existing map generalization techniques. We extend it to mobile environments, and implement. This thesis also includes the issue of discriminative data simplification technique according to display level and map display interface suitable for mobile devices. Research results an estimated by experiments.

STUDY ON DESIGN AND APPLICATION FOR TRAFFIC THEMATIC MAP LEVEL 1 DATA

  • Kim, Soo-Ho;Ahn, Ki-Seok;Kim, Moon-Gie
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.262-265
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    • 2008
  • We design level 1 traffic thematic map for common data structure. Level 1 means the road that can passing cars. If public office and private company use this form, they can save amount of money from overlapping update. And widely use of traffic analysis, navigation and traffic information system. For design common data structure we compared several data structure(traffic thematic map, ITS standard node/link, Car navigation map), and generalization these characteristic data. After generalization we considered about application parts. It can use of public part(traffic analysis, road management, accident management) and private part(car navigation, map product, marketing by variable analysis) etc.

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Developing a Work Procedure for Efficient Map Generalization (효율적인 일반화 자료처리를 위한 작업공정 개발)

  • Choi, Seok-Keun;Kim, Myung-Ho;Hwang, Chang-Sup
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.3
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    • pp.73-82
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    • 2003
  • This paper proposes a work procedure for generalizing large-scale digital maps ver. 2.0(1/5,000) into a small-scale digital map(1/25,000). Unlike a existent digital map, the digital map ver. 2.0 has a variety of attribute data as well as graphic data. To perform an efficient map generalization with these structural properties, we establish a work procedure as follow; firstly, delete layers which don't exist in small-scale digital map's feature code, and secondly, generalize features which have been classified into 8 layers, and finally merge 8 layers which have been generalized into 1 layer. Therefore, we expect that a work procedure which is proposed in this paper will play a fundamental role in automated generalization system and will contribute to small-scale digital mapping and thematic mapping.

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The Map Generalization Methodology for Korean Cadastral Map using Topographic Map (수치지형도를 이용한 연속지적도의 지도 일반화 기법 연구)

  • Park, Woo-Jin;Lee, Jae-Eun;Yu, Ki-Yun
    • Spatial Information Research
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    • v.19 no.1
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    • pp.73-82
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    • 2011
  • Recently, demand for the use of cadastral map is increasing in both public and private area. To use cadastral map in web or mobile environment, construction of the multi-representation database(MRDB) that is the compressed into multiple scale from the original map data is recommended. In this study, the map generalization methodology for the cadastral map by applying overlay with topographic map and polygon generalization technique is suggested. This process is composed of three steps, re-constructing the network data of topographic map, polygon merging of parcel lines according to network degree, and applying line simplification techniques. Proposed methodologies are applied to the cadastral map in Suwon area. The result map was generalized into 1:5,000, 1:20,000, 1:100,000 scale, and data compression ratio was shown in 15% 8% 1% level respectively.