• Title/Summary/Keyword: Artefacts

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Freeze-drying feces reduces illumina-derived artefacts on 16S rRNA-based microbial community analysis (Illumina를 이용한16S rRNA 기반 미생물생태분석에서 분변의 동결건조에 의한 인공적인 시퀀스 생성 감소효과)

  • Kim, Jungman;Unno, Tatsuya
    • Journal of Applied Biological Chemistry
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    • v.59 no.4
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    • pp.299-304
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    • 2016
  • When used for amplicon sequencing, Illumina platforms produce more than hundreds of sequence artefacts, which affects operational taxonomic units based analyses such as differential abundance and network analyses. Nevertheless it has become a major tool for fecal microbial community analysis. In addition, results from sequence-based fecal microbial community analysis vary depending on conditions of samples (i.e., freshness, time of storage and quantity). We investigated if freeze-drying samples could improve quality of sequence data. Our results showed reduced number of possible artefacts while maintaining overall microbial community structure. Therefore, freeze-drying feces prior to DNA extraction is recommended for Illumina-based microbial community analysis.

Chemical Composition of Archaeological Woods Submerged in the Seawater (수침고목재(水浸古木材)의 화학조성(化學組成))

  • Kim, Yoon-Soo;Bang, Joo-Wan;Kim, Ik-Joo;Choi, Kwang-Nam
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.2
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    • pp.3-7
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    • 1990
  • The chemical Composition of Chinese red pine (Pinus massoniana) submerged in the Yellow Sea for more than 700 years has been examined. When compared to the recent wood, the marked chemical changes in the waterlogged wood is the higher amount of lignin with lesser amount of holocellulose and abnormally high ash content. In the heavily degraded samples, the degradation of cellulose is more severe than that of hemicellulose. However, hemicellulose is much more attacked than the cellulose at the initial stage of deterioration in the sea water. Chemical analysis suggests that the cellulolytic marine microorganisms, whether they are fungi or bacteria. can be regarded as the primary agents for the destruction of the archaeological woods submerged in the sea water.

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Novel Flow Suppression Technique in MRI (핵자기 공명 영상에서 새로운 유속 흐름제거 방법)

  • Ro, Y.M.;Cho, Z.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.92-97
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    • 1992
  • The pulsatile nature of blood flow makes artefacts in 2D Fourier transform image. Spatial presaturation is known to be effective in eliminating flow artefacts when the spin echo acquisition is employed. However. this method requires additional RF pulse and spoiling gradient for presaturation. In this paper a new flow saturation technique which does not require additional saturation-RF and gradient is proposed. The proposed technique is equivalent to the existing saturation technique but the elimination of the flow component is achieved by a pair of tailored $90^{\circ}-180^{\circ}$ RF pulses in tile spin echo sequence. By use of two tailored RF pulses with opposite phase polarity, a linear phase gradient is generated for those moving materials and consequently all the spins of moving materials become dephased thereby no signal is observable. Computer simulations and experimental results obtained using both a phantom and a human volunteer with a 2.0 T whole body system are also presented.

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Suppressing Artefacts in the ECG by Independent Component Analysis (독립성분 분석기법에 의한 심전도 신호의 왜곡 보정)

  • Kim, Jeong-Hwan;Kim, Kyeong-Seop;Kim, Hyun-Tae;Lee, Jeong-Whan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.6
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    • pp.825-832
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    • 2013
  • In this study, Independent Component Analysis (ICA) algorithms are suggested to extract the original ECG part from the mixed signal contaminated with the unwanted frequency components and especially 60Hz power line disturbances. With this aim, we implement a novel method to suppress the baseline-wandering disturbances and power line artefacts contained in patch-electrodes sensory ECG data by separating the unmixed signal with finding the optimal weight W based on Kurtosis value. With applying brutal force and gradient ascent searching algorithm to find W, we can conclude that the unwanted frequency components especially in the ambulatory ECG data can be eliminated by Independent Component Analysis.

X-RAY FLUORESCENCE IN RESEARCH ON THE CULTURAL HERITAGE

  • Cechak, Tomas;Kopecka, Ivana;Musilek, Ladislav
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.321-326
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    • 2001
  • Radionuclide X-ray fluorescence analysis is a method, which has many advantages for analysing various historic artefacts, as it is relatively cheap, sensitive and non-destructive, and it allows measurements in-situ. However, this analysis has also certain limitations especially concerning sensitivity to chemical elements only, irrespective of the compounds or chemical forms in which these elements have been bonded. In addition, light elements emitting very soft X-rays cannot be measured, and in order to detect a wide range of elements, it is necessary to carry out repeated measurements with different radiation sources. Despite these limitations, valuable information can be obtained about the composition of historic materials and data about the origin and age of these artefacts can be derived. Analyses of wall paintings, ancient metal sculptures or other objects of art provide the basis for historic considerations documented in our results for some objects belonging to the Czech cultural heritage. The results are promising. Thus it is expected that our laboratory will expand its work into more fields of the fine and applied arts.

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Ambient Intelligence in Distributed Modular Systems

  • Ngo Trung Dung;Lund Henrik Hautop
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.421-426
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    • 2004
  • Analyzing adaptive possibilities of agents in multi-agents system, we have discovered new aspects of ambient intelligence in distributed modular systems using intelligent building blocks (I-BLOCKS) [1]. This paper describes early scientific researches related to technical design, applicable experiments and evaluation of adaptive processing and information interaction among I-BLOCKS allowing users to easily develop ambient intelligence applications. The processing technology presented in this paper is embedded inside each DUPLO1 brick by microprocessor as well as selected sensors and actuators in addition. Behaviors of an I-BLOCKS modular structure are defined by the internal processing functionality of each I-Blocks in such structure and communication capacities between I-BLOCKS. Users of the I-BLOCKS system can do 'programming by building' and thereby create specific functionalities of a modular structure of intelligent artefacts without the need to learn and use traditional programming language. From investigating different effects of modem artificial intelligence, I-BLOCKS we have developed might possibly contain potential possibilities for developing applications in ambient intelligence (AmI) environments. To illustrate these possibilities, the paper presents a range of different experimental scenarios in which I-BLOCKS have been used to set-up reconfigurable modular systems. The paper also reports briefly about earlier experiments of I-BLOCKS in different research fields, allowing users to construct AmI applications by a just defined concept of modular artefacts [3].

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Numerical Simulation of the Thermal Environment inside an Opened Tomb (개방된 고분내부의 열 환경 수치모사)

  • Lee, Kum-Bae;Youn, Young-Muk;Jun, Hee-Ho;Park, Jin-Yang;Ko, Seok-Bo
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.872-878
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    • 2006
  • In recent years the importance of the preservation of cultural artefacts like ancient tombs has been widely accepted domestically and internationally as the quality of life improves. However not much technical attention has been paid for the facilities and systems to preserve those artefacts. Even the general understanding of the preservatory environment of the underground space as tombs is poor. As a part of the present study, the temperature and relative humidity inside a selected artefact, Shinkwan-ri tomb, have been monitored for a year round by the present author to improve the understanding of the indoor thermal environment, is pursued to provide a predictive tool of numerical modelling of Shinkwan-ri tomb the opened underground space thermal environment. In this study, predictive numerical modelling of Shinkwan-ri tomb using the Computational Fluid Dynamics, calculate the velocity and temperature distribution and offer basic data which are necessary for the best fitted design of tomb air-conditioning device.

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Corrosion Prediction of Metallic Cultural Heritage Assets by EIS

  • Angelini, E.;Grassini, S.;Parvis, M.;Zucchi, F.
    • Corrosion Science and Technology
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    • v.18 no.4
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    • pp.121-128
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    • 2019
  • Electrochemical Impedance Spectroscopy (EIS) was used to predict corrosion behaviour of metallic Cultural Heritage assets in two monitoring campaigns: 1) an iron bar chain exposed indoor from over 500 years in the Notre Dame Cathedral in Amiens (France); and 2) a large weathering steel sculpture exposed outdoor from tens of years in Ferrara (Italy). The EIS portable instrument employed was battery operated. In situ EIS measurements on the iron chain could be used to investigate the phenomena involved in the electrochemical interfaces among various corrosion products and assess and predict their corrosion behaviour in different areas of the Cathedral. Meanwhile, the sculpture of weathering steel, like most outdoor artefacts, showed rust layers of different chemical composition and colour depending on the orientation of metal plates. The EIS monitoring campaign was carried out on different areas of the artefact surface, allowing assessment of their protective effectiveness. Results of EIS measurements evidenced how employing a simple test that could be performed in situ without damaging the artefacts surface is possible to quickly gain knowledge of the conservation state of an artefact and highlight potential danger conditions.

A Study of Conservation and Desalination Methods for an Iron Stele of the Joseon Dynasty (조선시대 철비(鐵碑)의 보존처리와 탈염방법 비교 연구)

  • Lee, Hye-Youn;Cho, Nam-Chul
    • Journal of Conservation Science
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    • v.25 no.4
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    • pp.399-409
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    • 2009
  • Outdoor iron artefacts are easily corroded by affection of environmental pollutants directly. Especially they need to be removed $Cl^-$ ions, but outdoor iron artefacts are excluded for desalination owing to their special features. Therefore this study contains the conservation processes of an iron stele of the Joseon Dynasty as the sample as well as desalination experiments that were carried out the desalting method using spill pads and the immersion desalting method together in order to compare. Desalting methods were compared by analyses such as an optical and metallurgical microscope, SEM-EDS, pH meter, Ion Chromatography and X-ray diffraction. As a result of the analysis, the optical and metallurgical microscopy show that the corrosion products are constituted by the layers and the metallurgical microstructure is a white cast iron. The SEM-EDS results of corrosion products detected mainly Fe, O, and especially Cl upto 2.48wt%. The results of pH and anion analysis for the washing solution, the desalting method using spill pads shows the similar effect to the immersion desalting method. As a result of XRD analysis before and after desalting corrosion products, goethite, magnetite, lepidocrocite and akaganeite are detected before desalting, but akaganeite is not detected after desalting at the desalting methode using spill pads, which indicates to have an effect on desalination. Therefore the results show that the desalting method using spill pads has an effect on desalination similar to the immersing desalting method.

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