• Journal of the Mineralogical Society of Korea
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• v.32 no.1
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• pp.63-69
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• 2019

The oxidation states of structural Fe in minerals reflect the paleo-depositional redox conditions for the biologically or abiotically induced mineral formation. Particularly, nano-scale analysis using high-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) is necessary to identify evidence for the microbial role in the biomineralization. HRTEM-EELS analysis of oxidation states of structural Fe and carbon bonding structure differentiate biological factors in mineralization by mapping the distribution of Fe(II)/Fe(III) and source of organic C. HRTEM-EELS technique provides geomicrobiologists with the direct nano-scale evidence of microbe-mineral interaction.

• Smart Structures and Systems
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• v.29 no.5
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• pp.729-746
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• 2022

In this paper, a nonlinear structural model updating methodology based on the Deep Belief Network (DBN) is proposed. Firstly, the instantaneous parameters of the vibration responses are obtained by the discrete analytical mode decomposition (DAMD) method and the Hilbert transform (HT). The instantaneous parameters are regarded as the independent variables, and the nonlinear model parameters are considered as the dependent variables. Then the DBN is utilized for approximating the nonlinear mapping relationship between them. At last, the instantaneous parameters of the measured vibration responses are fed into the well-trained DBN. Owing to the strong learning and generalization abilities of the DBN, the updated nonlinear model parameters can be directly estimated. Two nonlinear shear-type structure models under two types of excitation and various noise levels are adopted as numerical simulations to validate the effectiveness of the proposed approach. The nonlinear properties of the structure model are simulated via the hysteretic parameters of a Bouc-Wen model and a Giuffré-Menegotto-Pinto model, respectively. Besides, the proposed approach is verified by a three-story shear-type frame with a piezoelectric friction damper (PFD). Simulated and experimental results suggest that the nonlinear model updating approach has high computational efficiency and precision.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.3
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• pp.365-370
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• 2004

Simultaneous measurement with PLIF(Planar Laser-Induced Fluorescence) and Stereo-PIV(Stereo Particle Image Velocimetry) was performed to investigate the structural characteristics of flow field in Rushton Turbine Mixer. Instantaneous 3D velocity fields are measured by two 2K${\times}$2K CCD cameras focused on an object plane with the angular displacement methods while the concentration fields are obtained through the measurement of the fluorescence intensity of Rhodamine B tracer excited by the second pulse of Nd:Yag laser light. Image distortion due to the camera view-angle is compensated by a mapping function. Finally, the spatial structures of turbulent flow around Rushton turbine were identified by the calculation of synchronized data of the velocity field and concentration field.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.243-248
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• 1994

The purpose of this study is to develop Deterioration Diagnosis System for the Reinforced Concrete Structure which can be used preliminary in determining the factors causing deterioration by simple inspection and mapping of the indicators of deterioration. Total 29 items compromising material, structural and constructional factors causing deterioration were considered in this system. Also the indicators of deterioration were subdivided into 54 items such as concrete crack pattern and steel corrosion etc. Each indicator of deterioration was quantatified by allocating and giving grade to each item which has extra weight according to its conscquence. Satisfactory results were obtatined by applying this Diagnosis system to the indicators of deterioration in ref. [3]. Further research was required on the indicators of deterioration in construction site to enhance the field applicability of this system.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.24 no.2
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• pp.59-67
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• 2016

The checklist currently used for Aviation safety inspection performed by ASIs consists of inspection groups and multiple items, it does not have structured hierarchy system which required to efficiently process aviation safety analysis. On this study, through mapping taxonomy of HFACS onto current checklist to secure structured hierarchy system and present a specification on systematic frequency and severity to perform safety risk assessment of detected hazard.

• Structural Engineering and Mechanics
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• v.50 no.4
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• pp.541-561
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• 2014

This paper approaches the issue of seismic vulnerability assessment strategies for facade walls of traditional masonry buildings through the development of a methodology and its subsequent application to over 600 building facades from the old building stock of the historic city centre of Coimbra. Using the post-earthquake damage assessment of masonry buildings in L'Aquila, Italy, an analytical function was developed and calibrated to estimate the mean damage grade for masonry facade walls. Having defined the vulnerability function for facade walls, damage scenarios were calculated and subsequently used in the development of an emergency planning tool and in the elaboration of an access route proposal for the case study of the historic city centre of Coimbra. Finally, the methodology was pre-validated through the comparison of a set of results obtained from its application and also resourcing to a widely accepted mechanical method on the description of the out-of-plane behaviour of facade walls.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.06a
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• pp.204-207
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• 2001

뇌 MR 영상에서 질환을 자동적으로 진단하고 판별하는 작업은 정상인의 뇌 영상과의 비교를 통해서 가능하다. 정상인과의 뇌 영상 비교를 통하여 보다 정확하게 질병에 대한 근거를 제시할 수가 있기 때문에 이러한 접근 방법들이 여러 의료영상 연구 분야에서 시도되고 있다. 정상인의 뇌 영상과의 비교를 위해서는 우선적으로 해결되어야 하는 것이 현재의 대상 영상이 정상인 뇌의 어느 위치의 영상과 일치하는 지를 판별하는 문제이다. 따라서 본 연구는 이러한 뇌 매핑에 사용될 수 있는 특징들을 추출하기 위한 것으로, 뇌 매핑에 사용되는 특징들을 추출하기 위해서 뇌 MR 영상으로부터 대리영역, 뇌영역, 뇌척수액영역 그리고 눈영역을 분할한 후 이들의 윤곽선, 최소사각형과 각 영역들의 픽셀 정보들을 찾아낸다. 이는 추후 연구할 뇌 매핑을 위한 대분류에 사용될 수 있다.

• Proceedings of the KIPE Conference
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• 2014.11a
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• pp.179-180
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• 2014

본 연구에서는 회로 시뮬레이션을 통하여 얻은 ITER 전원 장치의 단락 전자기력의 방향과 크기 성분을 유한요소모델에 맵핑(mapping)한 뒤, 구조해석을 수행함으로써, 단락 시의 전자기력이 직접적으로 구조에 미치는 영향을 고찰하였다. 연구결과는 향후 전기적 구조물에 가해지는 다양한 악조건의 복합적 작용 시에 대한 고려에 있어 기초적인 데이터로 이용할 수 있으리라 사료된다.

• The Korean Journal of Ecology
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• v.21 no.4
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• pp.357-372
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• 1998

Land (scape) ecology is a trans-disciplinary science studying the related systems at the earth surface, in their visual, structural and functional aspects. it serves as an umbrella under which abiotic and biotic sciences, in an integrated way, study the for each relevant land attributes and their interrelations. The spatial aspects of these relations have a special interest. Landscape ecology my have a pure scientific purpose, but usually is executed in an applied context, related to land evaluation for land use and conservation. Depending on the aim and application of the study, one of the land attributes may get special attention. Vegetation mapping may contribute to landscape ecological study but also benefit from it especially in case of reconnaissance surveys. This is because in less detailed surveys of any land attribute, like land form, soil, vegetation, one must necessarily apply landscape ecological principles in the survey methodology, including remote sensing.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.96.2-96.2
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• 2014

Using solar occultation data obtained by Cassini/Visual Infrared Mapping Spectrometer (VIMS), we were able to retrieve the 1 - 5 mm optical-depth spectra of the Titanian haze, for which only selected wavelength and altitudinal ranges were previously analyzed. We found that the gross 1 - 5 mm shapes of the retrieved haze spectra are significantly different from the spectra of tholin samples in the literature. We also derived the vertical variation of the spectral structure of the $3.3-3.4{\mu}m$ absorption feature of the Titan haze from the VIMS data recorded between 250 and 700 km altitude. We found a marked change between 480 and 580 km in the relative amplitudes of the 3.33 and $3.38{\mu}m$ features which are characteristic of aromatic (double C=Cchains or rings) or aliphatic (single C-C chains) structural groups, respectively. Dicussions on this spectral and altitudinal variation will be presented.