• Korean Journal of Heritage: History & Science
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• v.51 no.4
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• pp.170-191
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• 2018

Until now, the Korean archeological community has only been able to introduce the findings of classical archaeology developed in the West, and it also suffers from a lack of concepts and academic achievements. The domestic archeological community also started to develop later than that of the West, when it began to analyze ancient history and relics through the classic works of history titled Samguk sagi (三國史記) and Samguk yusa (三國遺事). Furthermore, it is actively utilizing the Chinese classics, such as the Samgukji (三國志) and Huhanseo (後漢書), as well as certain Japanese classics such as Ilbonsegi (日本書紀). Due to the total lack of domestic classics, however, there are few details about the formation of ancient polities, national changes, and inter-country negotiations and exchanges, as well as numerous other unresolved issues. This study raises the need to revamp classical archaeology in order to solve these problems. The concept of classical means 'all records made in the past' in the shallow sense, while the meaning of the historiography means "historical records according to the taxonomy of the old book." Classical archaeology is a field in which the classics are analyzed and interpreted so as to study the culture of the past. This section has set up a wide range of classical categories, and has found that the classics can be used in a meaningful way in classical archaeology through the use of the Gongjagae (孔子家語). The use of the classics in classical archaeology could produce significant results if the relevant DB is managed by various institutions and organizations using proper techniques of analysis including big data analysis.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.19-28
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• 2021

Corrosion is the degradation of metals by reaction with the environment. It is difficult to completely remove. Corrosion proceeds rapidly after the protective barrier is destroyed, and several reactions occur that alter the composition and properties of the metal surface and local environments, such as diffusion of metal cations into the matrix, the formation of oxides, and local pH changes. The study of corrosion of steel and iron is of theoretical and practical interest and is receiving considerable attention. Acid solutions, which are widely used in industrial pickling, acid descaling, cleaning and acidification of oil wells, require the use of corrosion inhibitors to suppress corrosion attacks on metallic materials. Physical removal of rust requires expensive special equipment, and chemical removal of it can cause corrosion or shorten the life of the metal. In this study, an eco-friendly rust cleaner was developed using cosmetics and food materials by applying the concept of perm reducing agent and chelate, and applied to remove rust from industrial and hot water pipes and various industrial devices. As a result, it was found that rust cleaners remove rust more effectively and safely compared to conventional treatment methods. At the same time, the rust removal efficiency was 1.75 to 2.5 times better for industrial piping and 1.56 to 2.2 times better for boiler hot water than conventional methods.

• Journal of Christian Education in Korea
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• v.71
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• pp.241-276
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• 2022

Due to the 4th industrial revolution, which started with the Smart Revolution in the early 21st century, Hyper-Connectivity, Hyper-Convergence and Hyper-Intelligence of our society is accelerating. These changes induced formation of Metaverse as a fused new space that crosses the perimeter of the physical space and virtual(digital) spaces beyond time and place. The characteristics of Metaverse are continuously spread by engaging with the characteristics of the MZ generation, which collects both Millennial generation (M Generation) and Z Generation. With outburst of Covid-19 pandemic, a variety of attempts have been made to utilize Metaverse, even in church education when it was impossible to worship directly. In other words, the usefulness of the Metaverse was confirmed as a new community space of the education of the church. In addition, Metaverse may provide a substantial, experiential and evolving space for church education. However, in order for church education to further develop, the development in the method of education is also required to move beyond mere concept of space. In particular, when the learner-centered education method, one of the common characteristics of the Metaverse and MZ generation, it is thought that the church education in the Metaverse era will be able to go in a more evolving direction.

• Journal of the Korean Geotechnical Society
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• v.22 no.9
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• pp.45-59
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• 2006

The successful performance of any numerical geotechnical simulation depends on the accuracy and efficiency of the numerical implementation of constitutive model used to simulate the stress-strain (constitutive) response of the soil. The corner stone of the numerical implementation of constitutive models is the numerical integration of the incremental form of soil-plasticity constitutive equations over a discrete sequence of time steps. In this paper a well known two-surface soil plasticity model is implemented using a generalized implicit return mapping algorithm to arbitrary convex yield surfaces referred to as the Closest-Point-Projection method (CPPM). The two-surface model describes the nonlinear behavior of coarse-grained materials by incorporating a bounding surface concept together with isotropic and kinematic hardening as well as fabric formulation to account for the effect of fabric formation on the unloading response. In the course of investigating the performance of the CPPM integration method, it is proven that the algorithm is an accurate, robust, and efficient integration technique useful in finite element contexts. It is also shown that the algorithm produces a consistent tangent operator $\frac{d\sigma}{d\varepsilon}$ during the iterative process with quadratic convergence rate of the global iteration process.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.433-440
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• 1994

The exposure of Clamydomonas reinhardtii to low temperatures resulted in an accumulation of cellular pyruvate that dissipated when the chilled cells returned to ambient temperature. The dissipation of pyruvate accumulation was accompanied by an increase in the production level of superoxide radicals $(O_2^-)$ in cells. The formation of $O_2^-$ at an excessive level during the post-chilling period was apparently countered by a substantial activation of superoxide dismutase (SOD). All these results are similar to those observed previously in rice seedlings subjected to the cold-treatment, implicating that a common mechanism is probably underlying for the primary processes of chilling injury both in higher plants and in algae. It was also observed that the activation of Mn-containing SOD contributes the major share in the increase of SOD activity of whole algal cells. Because Mn-SOD is present only in mitochondria, the observation corroborates the concept that the $O_2^-$ scavenging enzyme would be induced to cope with the cold treatment-caused adverse situation in mitochondria where the toxic active oxygen is produced at rates far exceeding the normal rate.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.288-296
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• 2003

Generally, application of steel pipe pile as deep foundation member needs special requirement for the connection method between steel pipe pile and concrete footing. Even though two types of connection method are suggested in the related specification, type B-method is provident. To investigate real structural behavior of type B connection, several load tests are done with carefully designed experimental system. The purpose of this experiment is mainly focused on the understanding of actual behavior which can be predicted by design theory. At this research stage, vertical and lateral loading test are done for three types of specimen to review stress concentration, formation and behavior of imaginary RC column in the footing and effect of non-slip device installed in the steel pipe pile. The load resistance mechanism in these specific connection method is predicted based on both experimental results. The three-dimensional finite element modeling is also done for the purpose of comparison between numerical and experimental result. With all the results gained from experiment the structural behavior of imaginary RC column in the design concept is confirmed. The role of non-slip device is very important and it affects the resistance capacity with help of composite action of concrete and steel pipe pile.

• Korean Association of Arts Management
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• no.52
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• pp.5-37
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• 2019

Despite a copious volume of work on the relationship between social class and cultural consumption, scholars have paid scant attention to the increasingly apparent observation that a vast majority of the population exhibits indifference toward fine arts regardless of one's socio-economic status. Much of the prior literature on cultural consumption has treated the public's indifference to fine arts not as a distinct analytical category that deserves an explanation of its own, but simply as the opposite of "likes" or the act of consumption, let alone being disentangled from the concept of "dislikes" in taste-formation and consumption behavior. In this paper, we suggest that the seemingly increasing trend toward indifference to fine arts, especially among those who are part of the well-educated and economically well-off, merits close scholarly attention on its own term. As an initial step toward this endeavor, we explore the factors behind indifference toward fine arts among Korean middle-class, using the ground theory method. Our interview findings reveal that much of indifference toward fine arts is attributable to the lack of tastes in fine arts and artistic competence. Our results suggest that research drawing on Bourdieu's theory and Peterson's omnivore hypothesis needs to be further revised through an in-depth investigation of the institutional and societal contexts where art education takes place in Korea. We discuss the implications of our findings for policy-making in the cultural and artistic sphere.

• Journal of The Korean Association For Science Education
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• v.27 no.1
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• pp.59-69
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• 2007

The aim of this study was to investigate teachers' perceptions on MBL (microcomputer-based laboratory) experiment training program for teachers, the expecting effects of MBL experiment and application of MBL experiment after conducting MBL experiment training for science classes in schools. This study showed that most of the teachers who participated in the training program thought that the MBL experiment training program was very useful and instructive. Many teachers considered that MBL experiments using a computer could decrease time spent in the experiment by accurate and fast data collection and analysis. They also thought that the reduced time could be used more effectively in the analysis of experimental data and discussion activities leading to correct concept formation as well as in the development of graphical analysis and science process skills. However, they thought that MBL experiments were ineffective in learning how to operate experiment apparatus. This study also revealed that most teachers intended to apply MBL experiments in real classrooms context right after the training course and they pointed out many obstacles in introducing MBL experiments into their classrooms such as a budget to purchase equipment, poor laboratory conditions, and few MBL experiment training opportunities. In order to apply MBL experiment into the real classrooms, further changes were suggested as follows; development of technologies to reduce unit cost of equipment for MBL experiments, production and supply of many kinds of sensors, development of MBL experiment materials, and expansion of the training program for teachers.

• Journal of The Korean Association For Science Education
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• v.35 no.3
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• pp.477-485
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• 2015

In this study, we tried to find the effects of carrying out infographics instruction based on visual thinking with the infographics materials presented in physics textbooks targeting specialized vocational high school students. Thus, 60 students were divided into the experimental group and the control group, the experimental group had 25 classes composed of 'infographics concept formation, infographics understanding activity, and infographics configuration activity', on the other hand, the control group were instructed by lecture-type class. The results of this study are as follows: First, features of the infographics created by the students include changes in types of presentation from 'simple arrangement' to 'simple reconfiguration' and from 'illustration' to 'comparative analysis', which were made by the visual thinking of the students activated in accordance with the increase of their configuration times. Second, instruction by using infographics, visual thinking significantly improved in the level of understanding, visibility, usability, and communicability. Third, after instruction using infographics, the mean score of the experimental group's achievement significantly improved. Fourth, there was a significant improvement in the area of 'normality of scientist, attitude on scientific inquiry, and scientific attitude' in the test of attitudes toward science. From the analysis results, we could conclude that instruction using infographics enhance students' understanding of scientific concepts and communication capability by improving visual thinking abilities, which have a positive impact on academic achievement and attitudes toward science.

• Journal of Nutrition and Health
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• v.41 no.8
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• pp.691-700
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• 2008

One suggested mechanism underlying copper (Cu) deficiency teratogenicity is a low availability of nitric oxide (NO), signaling molecule which is essential in developmental processes. Increased superoxide anions secondary to decreased activities of Cu-zinc superoxide dismutase (Cu-Zn SOD) in Cu deficiency can interact with NO to form peroxynitrite, which can nitrate proteins at tyrosine residues. In addition, peroxynitrite formation can limit NO bioavailability. We previously reported low NO availability and increased protein nitration in Cu deficient (Cu-) embryos. In the current study, we tested whether Cu deficiency alters downstream signaling of NO by assessing cyclic GMP (cGMP) and phosphorylated vasodilator-stimulating phosphoprotein (VASP) levels, and whether NO supplementation can affect these targets as well as protein nitration. Gestation day 8.5 embryos from Cu adequate (Cu+) or Cu- dams were collected and cultured in either Cu+ or Cu- media for 48 hr. A subset of embryos was cultured in Cu- media supplemented with a NO donor (DETA/NONOate; 20 ${\mu}M$) and/or Cu-Zn SOD. Cu-/Cu- embryos showed a higher incidence of embryonic and yolk sac abnormalities, low NO availability, blunted dose-response in NO concentrations to increasing doses of acetylcholine, low mRNA expression of endothelial nitric oxide synthase (eNOS), increased levels of 3-nitrotyrosine (3-NT) compared to Cu+/Cu+ controls. cGMP concentrations tended to be low in Cu-/Cu- embryos, and they were significantly lower in Cu-/Cu- yolk sacs than in controls. Levels of phosphorylated VASP at serine 239 (P-VASP) were similar in all groups. NO donor supplementation to the Cu- media ameliorated embryonic and yolk sac abnormalities, and resulted in increased levels of cGMP without altering levels of P-VASP and 3-NT. Taken together, these data support the concept that Cu deficiency limits NO availability and alters NO/cGMP-dependent signaling in Cu- embryos and yolk sacs, which contributes to Cu deficiency-induced abnormal development.