• Title/Summary/Keyword: Data Preprocessing

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A comparative study of Depth Preprocessing Method for 3D Data Service Based on Depth Image Based Rendering over T-DMB (지상파 DMB에서의 깊이 영상 기반 렌더링 기반의 3차원 서비스를 위한 깊이 영상 전처리 기술의 비교 연구)

  • Oh, Young-Jin;Jung, Kwang-Hee;Kim, Joong-Kyu;Lee, Gwang-Soon;Lee, Hyun;Hur, Nam-Ho;Kim, Jin-Woong
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.815-816
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    • 2008
  • In this paper, we evaluate depth image preprocessing for 3D data service based on DIBR over T-DMB. We evaluate two preprocessing methods of depth images. These are gaussian smoothing and adaptive smoothing. The results show that adaptive smoothing is more suitable for images with sharp transition of depth.

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Data Preprocessing for Predicting Sarcopenia Based on Machine Learning (기계학습 기반 근감소증 예측을 위한 데이터 전처리 기법)

  • Yoon Choi;Yourim Yoon
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.737-744
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    • 2023
  • Sarcopenia is an increasingly common disease among the elder that has recently received attention. Although the causes of sarcopenia are diverse, aging, dietary habits, lack of exercise are the one of the major factors. As the causes of sarcopenia are diverse, it is important to develop strategies for prevention and treatment. However, predicting sarcopnia accuartely is difficult due to the variety of factors involved. Here, machine learning can significantly improve the accuracy and convenience of predicting sarcopenia. However, since lifestyle habits and biological data are vast, using data without preprocessing may be inappropriate in terms of time complexity and accuracy. This paper reviews recent literature on sarcopnia and its causes, focusing on preprocessing the data to be used in sarcopnia prediction machine learning accrodingly.

PREPROCESSING EFFECTS ON ON-LINE SSC MEASUREMENT OF FUJI APPLE BY NIR SPECTROSCOPY

  • Ryu, D.S.;Noh, S.H.;Hwang, I.G.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11c
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    • pp.560-568
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    • 2000
  • The aims of this research were to investigate the preprocessing effect of spectrum data on prediction performance and to develop a robust model to predict SSC in intact apple. Spectrum data of 320 Fuji apples were measured with the on-line transmittance measurement system at the wavelength range of 550∼1100nm. Preprocess methods adopted for the tests were Savitzky Golay, MSC, SNV, first derivative and OSC. Several combinations of those methods were applied to the raw spectrum data set to investigate the relative effect of each method on the performance of the calibration model. PLS method was used to regress the preprocessed data set and the SSCs of samples, and the cross-validation was to select the optimal number of PLS factors. Smoothing and scattering corection were essential in increasing the prediction performance of PLS regression model and the OSC contributed to reduction of the number of PLS factors. The first derivative resulted in unfavorable effect on the prediction performance. MSC and SNV showed similar effect. A robust calibration model could be developed by the preprocessing combination of Savitzky Golay smoothing, MSC and OSC, which resulted in SEP= 0.507, bias=0.032 and R$^2$=0.8823.

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Design and Development Study of a Trust-based Decentralized User Authentication System with Enhanced Data Preprocessing Functionality in a Metaverse Environment (메타버스 환경에서 Data Preprocessing 기능을 개선한 Trust-based Decentralized User Authentication 시스템 설계 및 개발 연구)

  • Suwan Park;Sangmin Lee;Kyoungjin Kim
    • Convergence Security Journal
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    • v.23 no.4
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    • pp.3-15
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    • 2023
  • As remote services and remote work become commonplace, the use of the Metaverse has grown. This allows transactions like real estate and finance in virtual Second Life. However, conducting economic activities in the Metaverse presents unique security challenges compared to the physical world and conventional cyberspace. To address these, the paper proposes solutions centered on authentication and privacy. It suggests improving data preprocessing based on Metaverse data's uniqueness and introduces a new authentication service using NFTs while adhering to W3C's DID framework. The system is implemented using Hyperledger Indy blockchain, and its success is confirmed through implementation analysis.

Automated data interpretation for practical bridge identification

  • Zhang, J.;Moon, F.L.;Sato, T.
    • Structural Engineering and Mechanics
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    • v.46 no.3
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    • pp.433-445
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    • 2013
  • Vibration-based structural identification has become an important tool for structural health monitoring and safety evaluation. However, various kinds of uncertainties (e.g., observation noise) involved in the field test data obstruct automation system identification for accurate and fast structural safety evaluation. A practical way including a data preprocessing procedure and a vector backward auto-regressive (VBAR) method has been investigated for practical bridge identification. The data preprocessing procedure serves to improve the data quality, which consists of multi-level uncertainty mitigation techniques. The VBAR method provides a determinative way to automatically distinguish structural modes from extraneous modes arising from uncertainty. Ambient test data of a cantilever beam is investigated to demonstrate how the proposed method automatically interprets vibration data for structural modal estimation. Especially, structural identification of a truss bridge using field test data is also performed to study the effectiveness of the proposed method for real bridge identification.

Imaging Fractures by using VSP Data on Geothermal Site (지열지대 VSP 자료를 이용한 파쇄대 영상화 연구)

  • Lee, Sang-Min;Byun, Joong-Moo;Song, Ho-Cheol;Park, Kwon-Gyu;Lee, Tae-Jong
    • Geophysics and Geophysical Exploration
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    • v.14 no.3
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    • pp.227-233
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    • 2011
  • Attention has been focused on geothermal energy as an alternative energy because it is continuously operable without external supply. Most of geothermal anomalies in Korea are related to deep circulation of groundwater through a fracture system in granite area. Therefore it is very important to understand the distribution of the fracture system which is the main channel of ground water. In this research, we constructed the velocity models with a fracture system and the layered sediments, respectively, and generated synthetic data sets with them to verify the presented vertical seismic profiling (VSP) preprocessing scheme. We compared the results from conventional VSP preprocessing flow to those from VSP preprocessing flow considering fracture system. We noticed that the preprocessing flow considering fracture system retains more sufficient signal including down-going wave than conventional preprocessing. In addition, we applied 3D VSP prestack phase screen migration to the preprocessed reversed VSP (RVSP) data from Seokmo Island so that we were able to image fracture structure of the geothermal site in Seokmo Island.

A Fuzzy Time-Series Prediction with Preprocessing (전처리과정을 갖는 시계열데이터의 퍼지예측)

  • Yoon, Sang-Hun;Lee, Chul-Hee
    • Proceedings of the KIEE Conference
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    • 2000.11d
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    • pp.666-668
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    • 2000
  • In this paper, a fuzzy prediction method is proposed for time series data having uncertainty and non-stationary characteristics. Conventional methods, which use past data directly in prediction procedure, cannot properly handle non-stationary data whose long-term mean is floating. To cope with this problem, a data preprocessing technique utilizing the differences of original time series data is suggested. The difference sets are established from data. And the optimal difference set is selected for input of fuzzy predictor. The proposed method based the Takigi-Sugeno-Kang(TSK or TS) fuzzy rule. Computer simulations show improved results for various time series.

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Performance Analysis of Speech Recognition Model based on Neuromorphic Architecture of Speech Data Preprocessing Technique (음성 데이터 전처리 기법에 따른 뉴로모픽 아키텍처 기반 음성 인식 모델의 성능 분석)

  • Cho, Jinsung;Kim, Bongjae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.22 no.3
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    • pp.69-74
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    • 2022
  • SNN (Spiking Neural Network) operating in neuromorphic architecture was created by mimicking human neural networks. Neuromorphic computing based on neuromorphic architecture requires relatively lower power than typical deep learning techniques based on GPUs. For this reason, research to support various artificial intelligence models using neuromorphic architecture is actively taking place. This paper conducted a performance analysis of the speech recognition model based on neuromorphic architecture according to the speech data preprocessing technique. As a result of the experiment, it showed up to 84% of speech recognition accuracy performance when preprocessing speech data using the Fourier transform. Therefore, it was confirmed that the speech recognition service based on the neuromorphic architecture can be effectively utilized.

Development and Application of a Big Data Platform for Education Longitudinal Study Analysis (교육종단연구 분석을 위한 빅데이터 플랫폼 개발 및 적용)

  • Park, Jung;Cho, Wan-Sup
    • The Journal of Bigdata
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    • v.5 no.1
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    • pp.11-27
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    • 2020
  • In this paper, we developed a big data platform to store, process, and analyze effectively on such education longitudinal study data. And it was applied to the Seoul Education Longitudinal Study(SELS) to confirm its usefulness. The developed platform consists of data preprocessing unit and data analysis unit. The data preprocessing unit 1) masking, 2) converts each item into a factor 3) normalizes / creates dummy variables 4) data derivation, and 5) data warehousing. The data analysis unit consists of OLAP and data mining(DM). In the multidimensional analysis, OLAP is performed after selecting a measure and designing a schema. The DM process involves variable selection, research model selection, data modification, parameter tuning, model training, model evaluation, and interpretation of the results. The data warehouse created through the preprocessing process on this platform can be shared by various researchers, and the continuous accumulation of data sets makes further analysis easier for subsequent researchers. In addition, policy-makers can access the SELS data warehouse directly and analyze it online through multi-dimensional analysis, enabling scientific decision making. To prove the usefulness of the developed platform, SELS data was built on the platform and OLAP and DM were performed by selecting the mathematics academic achievement as a measure, and various factors affecting the measurements were analyzed using DM techniques. This enabled us to quickly and effectively derive implications for data-based education policies.

Adjusted Direct Orthogonal Signal Correction For High-Dimensional Spectral Data (고차원 스펙트라 데이터 분석을 위한 Adjusted Direct Orthogonal Signal Correction 기법)

  • Kim, Sin-Young;Kim, Seoung-Bum
    • Journal of Korean Institute of Industrial Engineers
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    • v.37 no.4
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    • pp.400-407
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    • 2011
  • Modeling and analysis of high-dimensional spectral data provide an opportunity to uncover inherent patterns in various information-rich data. Orthogonal signal correction (OSC) a preprocessing technique has been widely used to remove unwanted variations of spectral data that do not contribute to prediction or classification. In the present study we propose a novel OSC algorithm called adjusted direct OSC to improve visualization and the ability of classification. Experimental results with real mass spectral data from condom lubricants demonstrate the effectiveness of the proposed approach.