• International Journal of Railway
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• v.1 no.1
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• pp.20-29
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• 2008

Features of procedures of dynamic synthesis are considered at use of various interpretations or models of processes in mechanical oscillatory systems. Methodological bases for research of the wave processes develop, allowing receiving some features of distribution of indignations. Authors offer scientifically-methodical bases for the decisions received analytical by.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1920-1939
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• 2007

Features of procedures of dynamic synthesis are considered at use of various interpretations or models of processes in mechanical oscillatory systems. Methodological bases for research of the wave processes develop, allowing receiving some features of distribution of indignations. Authors offer scientifically-methodical bases for the decisions received analytical by.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.06a
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• pp.1-18
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• 2000

This paper describes firstly a prediction for desirable features of the machine tool in the year 2015 and beyond, and then delineates something definite in relation to some representative machine tools, which could be realised in very near future. The paper depicts furthermore another aspect of future machine tools, I. e., innovative structural designs. In addition, author asserts the importance of grass root-like knowledge, when predicting the desirable feature of machine tools future together with showing some evidences.

• Journal of Contemporary Eastern Asia
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• v.15 no.1
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• pp.27-40
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• 2016

This study uses a network approach to investigate the structural characteristics of sub-organizations within public research institutes in order to obtain their implications for organizational structures. We construct a network based on research similarities between sub-organizations because sub-organizations generally build their own research portfolios. We examine how sub-units are organized based on their structural features. The structural features are compared between three public research institutes in different countries: the Korean the Government-funded Research Institutes (GRIs), the Max-Planck-Gesellschaft in Germany, and the National Laboratories (NLs) in the United States. The structural comparison helps to identify organizational characteristics and to differentiate between them. We found little common ground in the research areas between the GRIs because individual sub-organizations have distinct research portfolios. Therefore, the organizational hierarchy of research in the GRIs is less matured than it is in other public research institutes. This study suggests that the GRIs need to establish integrated strategies in order to strengthen the common knowledge base.

• Structural Monitoring and Maintenance
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• v.6 no.1
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• pp.1-17
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• 2019

Preserving reservoir safety has recognized to be important for the public where a vast majority of dams are located upstream of greatly populated cities and industrialized areas. Buckling, floatation and cavitation have caused failure in the spillway gates and conveyance features during past catastrophic events; showed their vulnerability and need for regular inspection along with reviewing design calculations to ensure the spillway meet current design standards. This paper investigates the hydraulic and structural consideration of dam's spillway by evaluating the data of Karkheh Dam's. Discharge capacity, flood routings and cavitation damage risk were main features for hydraulic considerations where hydrostatic and hydrodynamic forces and stability conditions were considered in structural considerations.

• Journal of the Speleological Society of Korea
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• no.88
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• pp.38-44
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• 2008

This study aims to identify the efficiency by applying diverse index to the positions of vertex in the network among the network analysis methods in order to identify the relational location features of caves. The first consideration was about the relational location features according to the linking degree and centrality of cave. The second consideration was about the structural equivalence between caves or between caves and the surrounding tourists attractions. A variety of index examined in this study is very efficient for identifying the positions of caves in the network. Furthermore, the relational location features in consideration of surrounding tourists attractions identified the availability of more objective and quantitative expression. In particular, when there are other caves around a cave, it is also very useful to identify the structural equivalence or comparison with other caves.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.3
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• pp.86-90
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• 2020

Iron-sulfur (Fe-S) clusters are one of the most ancient yet essential cofactors mediating various essential biological processes. In prokaryotes, Fe-S clusters are generated via several distinctive biogenesis mechanisms, among which the ISC (Iron-Sulfur Cluster) mechanism plays a house-keeping role to satisfy cellular needs for Fe-S clusters. The Escherichia coli ISC mechanism is maintained by several essential protein factors, whose structural characterization has been of great interest to reveal mechanistic details of the Fe-S cluster biogenesis mechanisms. In particular, nuclear magnetic resonance (NMR) spectroscopic approaches have contributed much to elucidate dynamic features not only in the structural states of the protein components but also in the interaction between them. The present minireview discusses recent advances in elucidating structural features of IscU, the key player in the E. coli ISC mechanism. IscU accommodates exceptional structural flexibility for its versatile activities, for which NMR spectroscopy was particularly successful. We expect that understanding to the structural diversity of IscU provides critical insight to appreciate functional versatility of the Fe-S cluster biogenesis mechanism.

• Smart Structures and Systems
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• v.2 no.3
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• pp.253-274
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• 2006

The structural monitoring of multi-wire strands is of importance to prestressed concrete structures and cable-stayed or suspension bridges. This paper addresses the monitoring of strands by ultrasonic guided waves with emphasis on the signal processing and automatic defect classification. The detection of notch-like defects in the strands is based on the reflections of guided waves that are excited and detected by magnetostrictive ultrasonic transducers. The Discrete Wavelet Transform was used to extract damage-sensitive features from the detected signals and to construct a multi-dimensional Damage Index vector. The Damage Index vector was then fed to an Artificial Neural Network to provide the automatic classification of (a) the size of the notch and (b) the location of the notch from the receiving sensor. Following an optimization study of the network, it was determined that five damage-sensitive features provided the best defect classification performance with an overall success rate of 90.8%. It was thus demonstrated that the wavelet-based multidimensional analysis can provide excellent classification performance for notch-type defects in strands.

• Structural Monitoring and Maintenance
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• v.7 no.2
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• pp.149-166
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• 2020

This paper presents the results of an experimental investigation on a vibration-based damage identification framework for a steel girder type and a truss bridge based on acceleration responses to operational loading. The method relies on sensor clustering-based time-series analysis of the operational acceleration response of the bridge to the passage of a moving vehicle. The results are presented in terms of Damage Features from each sensor, which are obtained by comparing the actual acceleration response from the sensors to the predicted response from the time-series model. The damage in the bridge is detected by observing the change in damage features of the bridge as structural changes occur in the bridge. The relative severity of the damage can also be quantitatively assessed by observing the magnitude of the changes in the damage features. The experimental results show the potential usefulness of the proposed method for future applications on condition assessment of real-life bridge infrastructures.

• Journal of the Korean Ceramic Society
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• v.39 no.2
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• pp.109-112
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• 2002

The structural and optical features of Porous Silicon(PS) were investigated; the porous silicon was prepared by electrochemical etching of silicon wafers in HF solution. The morphologies and Photoluminescece(PL) features of the PS were investigated in terms of etching time, current density and aging conditions. The average pore diameter and pore depth were determined by current density and etching time, respectively. As-prepared PS exhibited the maximum PL peak at the wavelength of ∼ 450 nm. The degree of deviation from as-prepared PS during aging treatment seemed to depend on the microstructure as well as morphology of the PS. It is found that etching current density played an important role on the microstructural features of the PS.