• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.53-56
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• 2008

In this investigation, results of laboratory tests on six reinforce concrete flat plate interior connections with elongated rectangular column support which has been used widely in tall residential buildings are presented. The purpose of this study is to evaluate an effect of column aspect ratio(${\beta}$c=$c_1/c_2$) on the hysteretic behavior under earthquake type loading. The aspect ratio of column section was taken as 0.33${\sim}$3($c_1/c_2$=1/3, 1/1, 3/1). Other design parameters such as flexural reinforcement ratio of slab and concrete strength was kept constant as ${\rho}$=1.0%, 1.5% and $f){ck}$=40MPa, respectively. Gravity shear load($V_g$) was applied by 30 percents of nominal vertical shear strength(0.3$V_o$) of the specimen. Experimental observations on punching failure pattern, peak lateral-load and story drift ratio at punching failure, and stiffness degradation were achieved and discussed in accordance with different column aspect ratio.

• Journal of the Korean Institute of Landscape Architecture
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• v.24 no.2
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• pp.74-85
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• 1996

The objective of this study is to investigate the influence of viewing aspects based on formal aesthetics and psychophysica approaches of the MAISAN provincial park for landscape management. Two methods are applied in this study. First, according to the field study with map the quantitative analyses of the viewshed area, visual section and scenery types were achieved, herein the visual landscape characteristics is found. Second, based upon visual preference evaluation of the relationships between the viewing aspects and visual preference scores to landscape slides were measured by questionnaires. The main conclusions obtained by the research are as follows. Visual area of MAISAN has a quite wide viewshed though itself is surrounded. The preference for the visual terminal were change by its characteristics to the visual corridors, view points, viewing types and viewing distance. Especially, the regression analysis between visual preference and viewing distance indicated Y=-3.20X\sup 2\+18.64X+20.64. In this case, viewing distance 794m from O\sub p\ is more important point for visual experience. The viewing types B·C and famous view A obtained a high visual preference score. A visual terminus are viewed along an entire RouteA, so revealed by its evolving spatial containment as to exact the full potential of its changing perspectives. Also we conducted the degree of visual influence by the shade in visual area at MAISAN and clarified viewing vantage Route and point in LSH being necessary for landscape preservation.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.56-62
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• 2013

The occurrence of the ventricular fibrillation is directly dependent on the magnitude and duration of the current. The current which flows through the human body is proportional to the touch voltage applied across the body and is in inverse proportion to the impedances in the circuit. The circuit impedances consist of human body impedance, line impedance, equipment impedance, earth terminal impedance and impedance of shoes which a person put on. The impedance of shoes greatly affect the severity of the electric accidents. The human body impedances relevant to the contact areas, contact conditions, current paths and touch voltages are already determined in the IEC 60479-1. However, the impedance of shoes is ignored or substituted by a simple value because of the absence of the sufficient data. For example, the impedance of shoes plus ground contact resistance is postulated to be $1,000{\Omega}$ in the IEC 61200-612. In IEEE 80, the shoe resistance plus ground contact resistance is assumed to be bare foot with ${\rho}/4b{\Omega}$. In this paper, we measured and analyzed the impedance of shoes with respect to conditions such as applied weight, environment variables and voltages. The results showed that the impedance of shoes is dependent on environment variables regardless of the types of shoes. Most of shoes showed the correlation with the applied force, whereas a few shoes showed characteristics related to the applied voltage. In terms of severity of electric shock, one thirds of test samples indicated to be dangerous in saltwater conditions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.6
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• pp.337-341
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• 2016

In this study, $ Ni_{0.79}(Mn_{2.21-x}Cu_x)O_4$ (x=0~0.25) specimens were prepared by using a conventional mixed oxide method. All specimens were sintered in air at $1,200^{\circ}C$ for 12 h and cooled at a rate of $2^{\circ}C/min$ to $800^{\circ}C$, subsequently quenching to room temperature. We investigated the structural and electrical properties of $ Ni_{0.79}(Mn_{2.21-x}Cu_x)O_4$ specimens with variation of CuO amount for the application of NTC thermistors. As results of X-ray diffraction patterns, all specimens showed the formation of a complete solid solution with cubic spinel phase. The relationship between ln ${\rho}$ and the reciprocal of absolute temperature(1/T) for the NTC thermistors was shown linearity, which exhibited the typical NTC thermistor properties. With increasing the amount of CuO, resistivity at room temperature, B-value, and temperature coefficient resistance decreased.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.174-178
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• 2005

Destruction of marine ecology system induced by the bal last water discharged from ships is one of the most serious problem among the various ship associated environmental impacts. International Maritime Organization (IMO) has actively dealt with this problem for a long time and is going to start to activate very strong international treatment for preventing ocean from such serious environmental impact. Various technologies of ballast water treatment are now being developed all over the world. In this paper, recent trend of existing ballast water treatment technologies is investigated in detail. Furthermore, in order to apply electrolysis technology to ballast wale r treatment, its basic principle is reviewed theoretically and its feasibility is checked through some in-situ experiments. Quite good results are shown in the experiments enough to confirm its applicability in ballast water treatment.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.1
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• pp.21-27
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• 2020

Somatic cell nuclear transfer derived embryonic stem cells (NT-ESCs) have significant advantages in various fields such as genetics, embryology, stem cell science, and regenerative medicine. However, the poor establishment of NT-ESCs hinders various research. Here, we applied fasudil, a Rho-associated kinase (ROCK) inhibitor, to develop somatic cell nuclear transfer (SCNT) embryos and establish NT-ESCs. In the study, MII oocytes were isolated from female B6D2F1 mice and performed SCNT with mouse embryonic fibroblasts (MEFs). The reconstructed NT-oocytes were activated artificially, and cultured to blastocysts in KSOM supplemented with 10 μM fasudil. Further, the blastocysts were seeded on inactivated MEFs in embryonic stem cell medium supplemented with 10 μM fasudil. A total of 26% of embryos formed into blastocysts in the fasudil treated group, while this ratio was 44% in the fasudil free control group. On the other hand, 30% of blastocysts were established NT-ESCs after exposure of fasudil, which was significantly higher than the control group (10%). The results suggest that fasudil reduced blastocyst development after SCNT due to inhibition of 2 cell cleavage while improved the establishment of NT-ESCs through the anti-apoptotic pathway.

• Journal of the Korean Institute of Gas
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• v.6 no.1 s.17
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• pp.1-9
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• 2002

This paper presents simple models for flow and the PIG dynamics when it passes through a $90^{\circ}$ curved section of pipeline. The simulation has been done with two different operational boundary conditions. The solution fur non-linear hyperbolic partial equations for flow is given by using MOC. The Runge-Kuta method is used to solve the initial condition equation fur flow and the PIG dynamics equation. The simulation results show that the proposed model and solution can be used fur estimating the PIG dynamics when the pig runs in the pipeline including curved section. In this paper, dynamic modeling and its analysis for the PIG flow through $90^{\circ}$ curved pipe with compressible and unsteady flow are studied. The PIG dynamics model is derived by using Lagrange equation under assumption that it passes through 3 different sections in the curved pipeline such that it moves into, inside and out of the curved section. The downstream and up stream flow dynamics including the curved sections are solved using MOC. The effectiveness of the derived mathematical models is estimated by simulation results fur a low pressure natural gas pipeline including downward and upward curved sections. The simulation results show that the proposed model and solution can be used for estimating the PIG dynamics when we pig the pipeline including curved section.

• Journal of the Korean Institute of Gas
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• v.6 no.1 s.17
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• pp.10-16
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• 2002

This paper introduces developed prototype intelligent pig which detects corrosion on pipeline by using Magnetic Flux Leakage technology. The 8 inch developed MFL(Magnetic Flux Leakage) pig is composed of 5 yokes which magnetize pipeline wall and 45 Hall sensors which detect MFL signal. The designed MFL modules are analyzed by using magnetic circuit method in order to confirm whether pipeline wall is fully saturated. A variety of artificial defects are manufactured on 8 inch diameter steel pipeline in order to acquire MFL signals. So leakage flux of the axial, radial and circumferential component was acquired as defects. The results of this paper show that design technique for 8 inch MFL pig can be applied to large diameter MFL pig and 0.5mm defect depth can be detected.

• Asia pacific journal of information systems
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• v.20 no.1
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• pp.1-31
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• 2010

One of the prominent challenges of e-government identified in developing countries is low level of ICT literacy and skills of e-government users. For those countries at the nascent stage of e-government development, it is crucial to identify and provide e-skills needed from the demand side. However, prior research has mostly focused on the supply side of e-skills, ignoring the consumption side of e-skills. In addition, no user centric approach for e-skills identification and development for e-service consumption, with respect to the stages of e-government development, have been proposed and validated. The purpose of this article is thus to: 1) Identify skills required for e-services utilization by all participants-citizens, public, and private sector employees-involved in G2C, G2B, and G2E e-government relationships respectively; assuming they are consumers of e-government and to 2) Propose and validate an user-centric approach for e-skills identification and development based on stages of e-government utilizing the Delphi method. As a result of the study, a comprehensive list of e-skills (N = 81) was generated. We found that e-skills required for e-service consumption are not merely technical; they include a wide variety of related skills that can be applied to enhancing e-skills. Therefore, the findings can serve as a standard curriculum for training and educating both citizens and government employees in developing countries. Moreover, the findings of this research may also facilitate international organizations in indentifying and measuring citizens' readiness for e-government in terms of e-skills.

• Journal of the Korean Society of Food Culture
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• v.31 no.6
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• pp.597-604
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• 2016

This study was performed to investigate the quality characteristics of lotus root tea (LT) prepared with Gardenia jasminoides powder (GLT) and Rubus coreanus Miquel powder (RLT). The proximate compositions, physicochemical properties, mineral contents, and sensory evaluations of samples were measured. GLT sample showed higher contents of crude protein, crude fat, crude ash, and moisture (p<0.001) as well as pH (p<0.001) compared to LT and RLT. In terms of color, lightness (L) and yellowness (b) of GLT were the highest among the samples, whereas redness (a) of GLT was the lowest. The results of mineral analysis showed that the mineral contents of K, Ca, and Fe of LT were the highest, whereas the content of Mg of GLT was the highest. The results of browning color intensity of all samples showed that LT had the lowest. GLT showed higher contents of water soluble solids than LT and RLT. In the sensory evaluation, the scores of color, flavor, aftertaste, feeling of throat, and overall preference of LT and GLT were significantly higher than those of RLT. From the findings, this study suggests that addition of Gardenia jasminoides powder was effective for preparation of lotus root tea in the aspects of consumer acceptability.