• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.6
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• pp.897-908
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• 2019

The objective of this study is to evaluate the field support performance of highperformance lattice girder (BK-Lattice Girder) by using numerical analysis. Three types (50, 70, 95-type) of existing and high performance lattice girders were applied to the cross section of highway 2, 3, and 4 lane tunnels to compare the supporting performance. The numerical analysis was the finite element method and the lattice girder was modeled in three dimensions with an elasto-plastic frame. The ground was modeled as a spring receiving only compression. The load was applied as a concentrated load on the central ceiling of the tunnel section. The yield strengths of the lattice girders were determined from the numerical results to compare the supporting performance of lattice girder. In case of 50-type, the yield strengths of high-performance lattice girders were increased by 6.7~10.0% compared with those of the existing lattice girders. In the case of 70-type, the high-performance lattice girders increased yield strengths by 12.1~14.9% than the existing lattice girder. In the case of 95-type, the high-performance lattice girders increased yield strengths by 13.3~20.0% than the existing lattice girder. As a result of numerical analysis, it was considered that the high-performance lattice girder supported better than the existing lattice girder when only the lattice girders were constructed.

• Journal of Animal Science and Technology
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• v.51 no.4
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• pp.329-336
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• 2009

The objective of this study was to investigate the relationship between measurements of color and water-holding capacity (WHC) in pork loin. A total of 419 pork loins were sampled from crossbred (Landrace$\times$Jeju native black pig) F2 pigs at a commercial slaughter house. Meat color measurements (CIE $L^*$, $a^*$, $b^*$), chroma ($C^*$) and hue angle (h) were measured with the Minolta Chromameter and WHC was measured by filter paper fluid, drip loss and cooking loss. Also pH, moisture content and crude fat content were measured at 24 hr postmortem. CIE $L^*$, $b^*$ and h values had positive correlation with drip loss (r=0.52, 0.42), but CIE $a^*$ and $C^*$ values were not related to drip loss. Results showed that CIE $L^*$, $b^*$, and h color system was better than CIE $L^*$, $a^*$, $b^*$ color system to predict WHC, especially drip loss. pH was negatively correlated to drip loss (-0.42) and CIE $L^*$ (-0.67). Although CIE $L^*$ and pH were correlated to drip loss, the accuracy of their estimates for drip loss was 27% and 17%, respectively. Consequently, it was confirmed that meat color and WHC were not perfectly related and suggested that CIE $L^*$, $b^*$, and h color space should not be used independently to predict WHC of pork loin.

• Korean Journal of Social Welfare Studies
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• v.48 no.1
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• pp.91-111
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• 2017

Purposes of this study, summoning thoughts and activities of Toynbee Hall of the UK and Hull House of the US held in between the end of 19C and the early 20C, are two folded: first, it is to examine the momentum and aims for which 'social' work was progressively established at that time; second, it is to look for implications for today's social work practice through understanding their characteristic activities and the context in which 'social' work was devised as an alternative in the two nations. The study method mainly relies on literature review, but further goes on to analyze the spirit of the age when settlement house was constructed as a welfare space and activities, leadership demonstrated in there, and to draw meanings for today, in terms of three dimensions: aim and location, professionality and education, and social action. Some of useful findings are: first, the COS and settlement house need to be considered in a continuum of socially responsive remedies against poverty and social work practice was developed in the process of 'suggestion-performance-critique-alternative suggestion-emergence of social work', rather than contrasting the two as opposite roots of social work practice. Second, settlement house was a socially constructed welfare space that contained intersectional dynamics of class, gender, personal vs. social, private vs. public, surrounding poverty issue. Third, besides differences between the two settlements, both purported for public goods and well-being and tried to realize the 'social' in that society. Lastly, this study explored historical meanings of settlement house as the welfare space with critical questions and discussed implications for social work practice today.

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.805-810
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• 2008

Using metallic Ti powder as raw materials and 1,2-diaminocyclohexane (DACH) as the trial template, two novel reduced titanophosphate open-structures were hydrothermally isolated by varying the $H_3PO_4/H_2O$ ratio to adjust the pH value. TiPO-1 crystallizes in orthorhombic Pbca space group with cell parameters a = 21.956(3) $\AA$, b = 8.6268(11) $\AA$, c = 7.2883(9) $\AA$, V = 1380.5(3) $\AA^3$, Z = 4. TiPO-2 crystallizes in triclinic space group P$\bar{1}$ with parameters a = 5.1620(10) $\AA$, b = 8.815(2) $\AA$, c = 10.655(3) $\AA$, $\alpha$ = $99.45^{\circ}$, $\beta$ = $102.94^{\circ}$, $\gamma$ = $91.06^{\circ}$, V = 465.34 $\AA^3$. TiPO-1 is constructed by infinite -Ti-O-Ti-O- linkage that is capped by $PO_4$ groups to form a chain structure with protonated DACH molecules occupying the interchain spaces. TiPO-2 represents a rare 3-D reduced titanophosphate with 12-MR channels. The structure of TiPO-2 is a neutral framework with water molecules located in the channels.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.1
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• pp.21-30
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• 2022

The restart of scramjet engine is almost impossible in case its unstart happens during engine operation. Therefore, it is essential to prognosticate the scramjet engine unstart phenomena. A numerical simulation of a scramjet engine is conducted to investigate the unstart process of the scramjet engine by adjusting the backpressure at the isolator outlet to the engine analysis environment. The start and unstart of the engine are identified by applying a support vector machine (SVM) through the data measured by wall pressure so that the locations of the pressure sensors most suitable for the unstart detection are selected. And the operation conditions in which the engine is avoid to be unstarted are quantified to perceive the safety margin.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.83-87
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• 2010

Crystal structure of coumarin 6 has been solved by X-ray diffraction. The crystals are triclinic, space group P-1, with a=8.823(2) ${\AA}$, b=8.898(2) ${\AA}$, c=11.025(9) ${\AA}$, ${\alpha}$=86.41(3)$^{\circ}$, ${\beta}$=85.39(3)$^{\circ}$, ${\gamma}$=76.23(3)$^{\circ}$, Mr=350.42, V=837.1(3) ${\AA}^3$, Z=2 and R=0.0516. The molecules are packed parallel to each other by weaker ${\pi}{\cdots}{\pi}$ and C-H${\cdots}{\pi}$ interactions. The detailed geometry of C-H${\cdots}{\pi}$ interactions were discussed. The hydrogen bonds and non-traditional C-H${\cdots}O$ interactions join the no-parallel molecules together. All the molecules packed wall-like with the molecular brick.

• Journal of Mechanical Science and Technology
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• v.16 no.9
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• pp.1040-1053
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• 2002

This research deals with the influence of nonlinearities associated with impact and sliding upon the rocking behavior of a rigid block, which is subjected to two-dimensional horizontal and vertical excitation. Nonlinearities in the vibration were found to depend strongly on the effect of the impact between the block and the base, which involves an abrupt reduction in the system's kinetic energy. In particular, when sliding occurs, the rocking behavior is substantially changed. Response analysis using a non-dimensional rocking equation was carried out for a variety of excitation levels and excitation frequencies. The chaos responses were observed over a wide response region, particularly, in the cases of high vertical displacement and violent sliding motion, and the chaos characteristics appear in the time histories, Poincare maps, power spectra and Lyapunov exponents of the rocking responses. The complex behavior of chaotic response, in phase space, is illustrated by the Poincare map. The distribution of the rocking response is described by bifurcation diagrams and the effects of sliding motion are examined through the several rocking response examples.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.493-496
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• 2000

This study is about the design and fabrication of optical voltage sensor modules improved in the insulation reliability, where we adopted the space-division voltage system using the auxiliary electrodes to apply the uniform electric fields to the BSO, the device of which the polarization state varies with the variation of refractive index in the electric fields. We measured the output of fiber-Optic Voltage Sensors with the temperature changes in the thermostatic oven. And we measured the output of Fiber-Optic Voltage Sensors after setting its up in the disttibuion automated switch being apply 60Hz alternating voltage from 6.6kV to 17.BkV. In result, measured error characteristic is good, so we can judge it is applicable to the practical case

• Journal of the Korean Geographical Society
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• v.49 no.6
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• pp.884-896
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• 2014

This study aims to identify the factors that contribute to the regional innovative capacity and to analyze the effects on the regional economic development including newly-established corporation and job creation. The results are as follows. First, as a result of factor analysis, the 14 variables were grouped into 3 factors, i.e. innovative input, infrastructure, and linkage. Second, the panel models were developed using the above factor scores and economic performance variables such as the number of newly-established corporation and employees. As a result, innovative capacity factors positively contributed to the newlyestablished corporation and job creation. The innovative input was the most influential factor determining the regional economic performance, followed by linkage and infrastructure. This study suggests several policy implications for the reinforcement of innovative capacity and regional competitiveness.

• Journal of Periodontal and Implant Science
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• v.47 no.1
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• pp.20-29
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• 2017

Purpose: The microstructural characteristics of trabecular bone were identified using micro-computed tomography (micro-CT), in order to develop a potential strategy for implant surface improvement to facilitate osseointegration. Methods: Alveolar bone specimens from the cadavers of 30 humans were scanned by high-resolution micro-CT and reconstructed. Volumes of interest chosen within the jaw were classified according to Hounsfield units into 4 bone quality categories. Several structural parameters were measured and statistically analyzed. Results: Alveolar bone specimens with D1 bone quality had significantly higher values for all structural parameters than the other bone quality categories, except for trabecular thickness (Tb.Th). The percentage of bone volume, trabecular separation (Tb.Sp), and trabecular number (Tb.N) varied significantly among bone quality categories. Tb.Sp varied markedly across the bone quality categories (D1: $0.59{\pm}0.22mm$, D4: $1.20{\pm}0.48mm$), whereas Tb.Th had similar values (D1: $0.30{\pm}0.08mm$, D4: $0.22{\pm}0.05mm$). Conclusions: Bone quality depended on Tb.Sp and number-that is, endosteal space architecture-rather than bone surface and Tb.Th. Regardless of bone quality, Tb.Th showed little variation. These factors should be taken into account when developing individualized implant surface topographies.