• Steel and Composite Structures
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• v.47 no.5
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• pp.633-644
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• 2023

Taking a look at the previously published papers, it is revealed that there is a porosity index limitation (around 0.35) for the mechanical behavior analysis of the functionally graded porous (FGP) structures. Over mentioned magnitude of the porosity index, the elastic modulus falls below zero for some parts of the structure thickness. Therefore, the current paper is presented to analyze the vibrational behavior of the FGP Timoshenko beams (FGPTBs) using a novel refined formulation regardless of the porosity index magnitude. The silica aerogel foundation and various hydrothermal loadings are assumed as the source of external forces. To obtain the FGPTB's properties, the power law is hired, and employing Hamilton's principle in conjunction with Navier's solution method, the governing equations are extracted and solved. In the end, the impact of the various variables as different beam materials, elastic foundation parameters, and porosity index is captured and displayed. It is revealed that changing hygrothermal loading from non-linear toward uniform configuration results in non-dimensional frequency and stiffness pushing up. Also, Al - Al2O3 as the material composition of the beam and the porosity presence with the O pattern, provide more rigidity in comparison with using other materials and other types of porosity dispersion. The presented computational model in this paper hopes to help add more accuracy to the structures' analysis in high-tech industries.

• Environmental and Resource Economics Review
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• v.20 no.2
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• pp.229-254
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• 2011

In this paper, we decomposed Greenhouse-Gas emissions of Korea's manufacturing industry using LMDI (Log Mean Divisia Index) method. Changes in $CO_2$ emissions from 1991 to 2007 studied in 5 different factors, industrial production (production effect), industry production mix (structure effect), sectoral energy intensity (intensity effect), sectoral energy mix (energy-mix effect), and $CO_2$ emission factors (emission-factor effect). By results, the structure effect and intensity effect has a role of reducing GHG emissions and The role of structure effect was bigger than intensity effect. The energy mix effect increased GHG emissions and emission-factor effect decreased GHG emissions. By time series analysis, IMF regime affected the GHG emission pattern. the structure effect and intensity effect in that regime was getting worse. After 2000, in the high oil price period, the structure effect and intensity effect is getting better.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.193-201
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• 2013

Recently there has been insignificant growth in the Korean construction management (CM) market, in comparison to the previous year. However, despite stagnation or even decreasing growth trends, the number of domestic companies participating in the CM market has increased rapidly. As follows, market movements of CM despite trending in stagnant growth or decrease, the market has been increasing firms which entry the market. The reasons for such dynamic change must be examined first, in order to facilitate analysis of its competitive structure. This study aims to examine the market competition structure and analyze the reason for proliferation of companies in the sick CM market. This study employs market concentration ratio and DEA-based Malmquist productivity indices to analyze the competitive structure of the CM market. Results reveal that the CM market has been monopolized by a few companies, but this is gradually changing. In addition, these companies were not productive, but there has been a gradual increase in the productivity index. Therefore, this study, which provides the direction index of the CM market, has implications for all major stakeholders in this market.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.21-26
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• 2008

A multi-geophysical surveys were carried out at Hwasan caldera which is located in Euisung Sub-basin. In order to overcome the limitation of the previous studies, dense gravity data and magnetotelluric (MT) data were obtained and integrated. In this study, the independent inversion models from gravity and MT method were integrated using a correlation and classification approaches to map geologic structure. The results of integration analysis indicated followings; 1) pyroclastic rocks around the central area of Hwasan caldera have lower density and resistivity when compared with those of neighborhood regions and are extended to around 1 km in depth, 2) the high resistivity and density intrusive igneous rocks are imaged around the ring fault boundary, and 3) the basement structure, which has low resistivity and high density, 5 km deep inferred by integration analysis. Also, for integration analysis, we suggested Structure Index method. This method is analyzed using Type Angle and Type Intensity, which are calculated by the spatial correlation of the physical properties. In this study, we can perform the integration analysis effectively using Structure Index method.

• The Journal of the Korea Contents Association
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• v.10 no.12
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• pp.300-308
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• 2010

This study empirically investigates the export structure change of OECD countries in the field of information technology from 1995 to 2005. We used Between and Within Entropy index to estimate the difference of export structure change rather than RCA index(simple export structure change). In addition, we also estimate the relationship between R&D activities and export difference. First, empirical findings showed that IT export market concentration is decreasing gradually, and changing to more competitive market structure. Second, compared to other OECD countries, Korean exports weight of information and communication industry can be seen higher than that of bio-industry. Third, Entropy index was increased from 1995 and then gradually decreased as the starting point of 2000. Finally, the relationship between R & D activities in the telecommunications industry and impact of the export structure changes was a positive.

• Textile Coloration and Finishing
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• v.28 no.3
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• pp.175-182
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• 2016

To investigate dyeing behaviors in accordance with dye structure in cold pad batch dyeing of cotton knit, monochlorotriazine-vinylsulfone bifunctional dyes and monofluorotriazine-vinylsulfone bifunctional dyes were prepared. The spectral property and solubility of the dyes were tested and compared with the imported dyes. In addition, exhaustion behaviors of individual and mixed dye solutions were measured to examine the influence of dye structure on dyeing behavior in cold pad batch dyeing. The substantivity, fixation, migration index and half dyeing time were also calculated for further analysis of dyeing behavior of the prepared dyes. As a result, both dyes exhibited the superior solubilities and satisfactory light absorption properties. Also, monofluorotriazine-vinylsulfone bifunctional dyes showed moderate sensitivity to alkalinity and proper kinetic index values compared with the monochlorotriazine-vinylsulfone bifunctional dyes and the imported dyes. The results indicated monofluorotriazine-vinylsulfone bifunctional structure of the dye is suitable for cold pad batch dyeing.

• Genomics & Informatics
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• v.9 no.2
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• pp.74-78
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• 2011

Numerous restraints and simplifications have been developed for methods that anticipate protein structure to reduce the colossal magnitude of possible conformational states. In this study, we investigated if globularity is a general characteristic of proteins and whether they can be applied as a valid constraint in protein structure simulations with approximated measurements (Gb-index). Unexpectedly, most of the proteins showed strong structural globularity (i.e., mode of approximately 76% similarity to the perfect globe) with only a few percent of proteins being outliers. Small proteins tended to be significantly non-globular ($R^2$=0.79) and the minimum Gb-index showed a logarithmic increase with the increase in protein size ($R^2$=0.62), strongly implying that the non-globular characteristics might be more acceptable for smaller proteins than larger ones. The strong perfect globe-like character and the relationship between small size and the loss of globular structure of a protein may imply that living organisms have mechanisms to aid folding into the globular structure to reduce irreversible aggregation. This also implies the possible mechanisms of diseases caused by protein aggregation, including some forms of trinucleotide repeat expansion-mediated diseases.

• Journal of the Korean Society for information Management
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• v.28 no.1
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• pp.123-144
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• 2011

This study compared Author Profiling Analysis(APA) to Author Co-Citation Analysis (ACA). The former is a new analytic technique on the intellectual structure of a science whereas the latter is a traditional analytic technique. The purpose of this study was to propose appropriate methods to analyze intellectual structure of a science in the Korean research environment. In order to achieve the goal, this study adopted APA using Text Mining for analysis on the intellectual structure of a science rather than relying on citation index in order to determine a potential utility of the new analytic technique that can identify the intellectual structure.

• Steel and Composite Structures
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• v.51 no.3
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• pp.289-304
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• 2024

The seismic performance of traditional steel frame-shear wall structures was significantly improved by the application of self-centering steel-reinforced concrete (SRC) wall-panel structures in the steel frames. This novel resilience functionality can rapidly restore the structure after an earthquake. The presented steel frame with steel-reinforced concrete self-centering wall-panel structures (SF-SCW) was validated, indicating its excellent seismic performance. The seismic design method based on bear capacity cannot correctly predict the elastic-plastic performance of the structure, especially certain weak floors that might be caused by a major fracture. A four-level seismic performance index, including intact function, continued utilization, life safety, and near-collapse, was established to achieve the ideal failure mode. The seismic design method, based on structural displacement, was proposed by considering performance objectives of the different seismic action levels. The pushover analysis of a six-floor SF-SCW structure was carried out under the proposed design method and the results showed that this six-floor structure could achieve the predicted failure mode.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.9-12
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• 2016

The process parameters of DC pulsed sputtering to produce a multi-layer thin film with light reflectance at a specific wavelength region were studied. The optical simulation of multi-layer thin films of the silicon dioxide ($SiO_2$) films with a low refractive index and the titanium dioxide ($TiO_2$) films with a high refractive index was done. Under a DC pulsed sputtering power of 2kW and 200 sccm(standard cubic centimeter per minute) argon gas, the silicon dioxide films with a refractive index of 1.46 in the range of oxygen gas ratios of 12% and a titanium dioxide film with a refractive index of 2.27 in the range of oxygen gas ratios of 1% were produced. The multi-layer structure of high refractive index/low refractive index/high refractive index was designed and fabricated. The characteristics of the fabricated multi-layer thin film structure showed a reflectance of more than 45% in the range, 780 to 1200nm. This multi-layer structure is expected to be used to block the near infrared wavelength light.