• Journal of the Korean Society for Precision Engineering
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• v.30 no.3
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• pp.271-277
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• 2013

Inconel 718 super alloy was aging heat treated at the temperature range from $675^{\circ}C$ to $785^{\circ}C$ for 5~40 hours after solution annealing at $1025^{\circ}C$ for 1 hour. The aging treated specimens were investigated microstructure, mechanical properties and thermal expansion/contraction. Precipitates appeared for a long time aging treatment were niobium carbide and also ${\gamma}^{\prime}$ phase. For the aging treatment time of 10 hours, the changes in strength and hardness with increasing aging treatment temperature showed the maximum value at the temperature of $725^{\circ}C$. This maximum value is to be related with the precipitation of ${\gamma}^{\prime}$ and ${\gamma}^{{\prime}{\prime}}$ phases. The decrease in strength, elongation and hardness during long time aging at $725^{\circ}C$ were thought to be induced from the coarsening of the grain size and the transformation of ${\gamma}^{{\prime}{\prime}}$ phase to ${\gamma}^{\prime}$ phase. For the specimens treated for 10 hours, impact energy showed constant value of ~105 J with increasing the aging temperature, however this value continuously decreased with elapsing time at the aging temperature of $725^{\circ}C$. It was found that the decrease in impact value was induced from the coarsening of grain size and the carbide coarsening. The coefficient of thermal expansion of aging treated Inconel 718 alloy increased with raising test temperature, and the coefficient was appeared $11.57{\sim}12.09{\mu}m/m{\cdot}^{\circ}C$ and $14.28{\sim}14.39{\mu}m/m{\cdot}^{\circ}C$, respectively, after heating to $150^{\circ}C$ and $450^{\circ}C$.

• Cross-Cultural Studies
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• v.47
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• pp.261-289
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• 2017

This article is a follow-up on the concept of philosopher/writer and its transformation in the Age of Enlightenment - 1. the dictionary meaning of the term 'philosopher/writer' and the origins of 'literary fields' of the Enlightenment era. In this article, we analyzed changes in the literary field in the late $17^{th}$ century after the expansion of the publishing market. We examined the conflict surrounding philosophers' identifying between modern and traditional philosophers. We have validated that the formation of new readers has made traditional philosophers more sensitive to the 'horizon of expectations' of readers. Some biographical works are also one of our concern. By the end of the $17^{th}$ century, philosophers and writers suddenly became objects of biographical works unlike in the past. Through our research, we found that readers have sought the arrival of a new hero, a great philosopher or a great writer, that will lead a new era, and due to this anticipation, it has led to the publication of biographical works. In this process, we have revealed conceptual changes about authors, writers, philosophers, and so on. In the next article, we will continue advanced discussion on the concept of philosopher/writer.

• Journal of Korea Water Resources Association
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• v.54 no.5
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• pp.289-299
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• 2021

This study analyzes bifurcation characteristics of the Seolmacheon experimental catchment by extracting the shape variation of channel network due to variable scale of source basin or threshold area. As the area of source basin decreases, a bifurcation process of channel network occurs within the basin of interest, resulting in the elongation of channel network (increase of total channel length) as well as the expansion of channel network (increase of the source number). In the former case, the elongation of channel reaches overwhelms the generation of sources, whereas, in the latter case, the drainage path network tends to fulfill the inner space of the basin of interest reflecting the opposite trend. Therefore, scale invariance of natural channel network could be expressed to be a balanced geomorphologic feature between the elongation of channel network and the expansion of channel network due to decrease of source basin scale. The bifurcation structure of the Seolmacheon experimental catchment can be characterized by the coexistence of the elongation and scale invariance of channel network, and thus a further study is required to find out which factor is more crucial to rainfall transformation into runoff.

• Journal of IKEEE
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• v.22 no.1
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• pp.38-45
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• 2018

An integrated cryptographic processor that efficiently integrates ARIA, AES block ciphers and Whirlpool hash function into a single hardware architecture is described. Based on the algorithm characteristics of ARIA, AES, and Whirlpool, we optimized the design so that the hardware resources of the substitution layer and the diffusion layer were shared. The round block was designed to operate in a time-division manner for the round transformation and the round key expansion of the Whirlpool hash, resulting in a lightweight hardware implementation. The hardware operation of the integrated ARIA-AES-Whirlpool crypto-processor was verified by Virtex5 FPGA implementation, and it occupied 68,531 gate equivalents (GEs) with a 0.18um CMOS cell library. When operating at 80 MHz clock frequency, it was estimated that the throughputs of ARIA, AES block ciphers, and Whirlpool hash were 602~787 Mbps, 682~930 Mbps, and 512 Mbps, respectively.

• Journal of the Korean housing association
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• v.25 no.6
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• pp.133-146
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• 2014

This study aims to analyze the changes of adjacent residential area after the restoration of covered urban streams in seoul. The changes of adjacent residential area after restoration were analyzed by changes of land using, urban structure, individual lot of land and architecture to investigate relationship of the urban stream and residential change. The result as follows: the first one is the change of land use and urban structure in adjacent residential area. This change of infrastructure through stream restoration has transformed land use and urban structure in adjacent residential area. Secondly, there is the changes of the individual lot of land. It seemed that new development by combined lots would be concentrated in stream-side blocks. But, the changes of lots such as combining or dividing lots tend to be concentrated in stream-side, main road and main streets. In stream-side, commercial function of land use has changed to residential one which has restored streams landscape by transformation of lots use without changes of ownership-lots. Finally, there is the change of architecture. It turned out new building in adjacent residential area is similar to general development. However, new building in streamside is related to direction of stream. In addition, remodeling and expansion tend to change in commercial buildings on stream-side bridges of corner lots intensively. As a result, it is related to expectation of architectural activation and improvement of sidewalk environment by stream restoration.

• Journal of the Korean Society of Costume
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• v.50 no.7
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• pp.75-96
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• 2000

Modern clothing is approached in the level of art, and it becomes the means of expressing individuality in modern society uniformed by the development of information society. In this modern society, modern men need the recovery of humanity and expectations of handcrafted skills for the succession of tradition culture. Prior to expressing individuality, we should examine our traditional culture and combine it with western culture. Quit started to be used for practical purpose such as life items, but it is expanded to the fields of art. Used in dress and its ornaments design, quilt is often applied to the addition of aesthetic factors or cubic material feelings by transforming its warming effect. Hereby, this study has a purpose to create high value added modern dross and its ornaments design by expressing the modern clothing is approached in the level of art, and it becomes the means of expressing individuality roe-dimensional characteristics of quilt, and applying the color combination and the surface of butterfly wings to dress and its ornaments design. The following are the results of this study. 1. The concept of quilt started for practical purposes, but it is expanded to decoration in modern times, and it is confirmed that quilt can be variously applied to handcrafted modern design. 2. Quilt removes the plane character of textile and it riches the three-dimensional material of dress and its ornaments. Applying these characteristics, the expression of transparent wings were possible with 3 transparent layers of textile. 3. The spledid color of butterfly wings are expressed by coloring oganza and felt, and the various colors of felt showed rich color gradation. 4. The form and pattern of butterfly wings are applied as modeling form and line, and the transformation. repetition and expansion of unit forms determined the form of quilting lines. By designing the characteristics of back wings for the composition line of clothing, the form characteristics of a motif could be emphasized. 5. By using felt, oganza, Damdam yarn and ostritch feathers in expressing butterfly wings, the warm material of Linbun is felt, and the tip hair of wings are expressed by croche techniques using Damdam yarn.

• Journal of the Korean Ceramic Society
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• v.30 no.4
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• pp.289-298
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• 1993

Properties in terms of the variation of the glass compositions, which were density (p), molar volume(Vm), atom/ion packing density (Dp), refractive index (nD), transformation temperature (Tg), dilatometric softening point (Td), thermal expansion coefficient (α), Young's modulus (E), and knoop hardness (KHN) were investigated in CaO-SiO2 glasses and CaO-P2O5-SiO2 glasses containing less than 10mole% of P2O5. Those properties were measured by density measurement kit, Abbe refractometer, dilatometer, ultrasonic pulse echo equipment, and micro hardness tester. When CaO content was increased in CaO-SiO2 glasses, p, Dp, nD, Tg, Td, α, E and KHN were increased, while Vm was decreased. When P2O5 was added to the CaO-SiO2 glasses with constant CaO/SiO2 ratio as 1.07, p, Dp, nD, Tg, Td, α, E and KHN were decreased, while Vm was increased. When the amount of P2O5 in glasses was kept constant, the changes of the properties with variation of CaO content in the CaO-P2O5-SiO2 glasses were very similar to those of CaO-SiO2 glasses. These phenomena could be explained by the structural role of P2O5 in the CaO-P2O5-SiO2 glasses, which was polymerization of siicate structures and resulted in [PO4] monomer structure in glasses. Due to this structural characteristics, the bond strength and packing density were changed with compositions. Proportional relationships between 1) np and Dp, 2) Tg, Td, α and CaO content, 3) E and Vm-1, and 4) KHN and P2O5 content were evaluated in this investigation.

• Journal of the Korean Society for Heat Treatment
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• v.28 no.6
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• pp.300-309
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• 2015

The aim of the present study was to predict the variations in microstructure and deformation occurring during gas carburizing and quenching processes of a SCM420H planetary gear in a real production environment using the finite element method (FEM). The motivation for the present study came from the fact that previous FEM simulations have a limitation of the application to the real heat treatment process because they were performed with material properties provided by commercial programs and heat transfer coefficients (HTC) measured from laboratory conditions. Therefore, for the present simulation, many experimentally measured material properties were employed; phase transformation kinetics, thermal expansion coefficients, heat capacity, heat conductivity and HTC. Particularly, the HTCs were obtained by converting the cooling curves measured with a STS304 gear without phase transformations using an oil bath with an agitator in a real heat treatment factory. The FEM simulation was successfully conducted using the aforementioned material properties and HTC, and then the predicted results were well verified with experimental data, such as the cooling rate, microstructure, hardness profile and distortion.

• Cartoon and Animation Studies
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• s.31
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• pp.29-55
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• 2013

In the contemporary modern society, information and knowledge generate a set of new social values. These changes demand a transformation not only in socio-cultural and educational spheres, but also, specifically, in the field of culture and art education. Culture and Art education emphasizes the integration and cross-discipline of other related fields which have great impact on culture and arts. This study applies theoretical analysis of Animation education in the context of culture and art education. Animation education takes an interdisciplinary approach to integrate various subjects in the field of culture and art education. Animation, as a form of culture and art education, plays an educational role in the social classroom. Animation education should be developed and expanded to become a regular classroom course. The goal of Animation education is to pursue and develop a connection with other educational courses of study. In order to strengthen the role of Animation education, we should first re-structure the pedagogical role of Animation education. Secondly, Animation education needs to become a diversified and popularized education. Third, the cultivation of creative human resources is considered of vital importance to Animation education. Finally, the expansion of infrastructure and the establishment of a comprehensive support system for Animation education has to be established.

• The Journal of Korean Society for School & Community Health Education
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• v.2 no.2
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• pp.23-38
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• 2001

The purpose of this study was to suggest a stratege of promoting school health. This study examined the historical aspacts of school health and conducted a mail questionnaire survey for 24 school health specialists who work in school and educational administration from November 1 to November 30, 2000 and the reply rate was 79.2%(19 persons). The results were as follows. The most important fields in schools were answered health related field. The most important field of school health were health education(89.5%), the supervisor of school health project should be office of school health ward in Educational administration(42.1%), and problems in conducting health project in school were lack of policy(63.5%), awareness of the importance of school health(63.2%), and budget(63.2%). They answered that the cause of food poisoning in school were negligence of sanitation of cook(42.1%) and prevention methods were thorough inspection of food stuffs(31.6%). 72.2% replied that school health project were not being operated in a proper way. They answered that tasks of promoting school health were development of school health policy, increase of man-power for school health, expansion of school health budget, systematic health education, and development of independent health subject program, connection with local society. 94.7% of those replied answered that school health organization is necessary. Common sense on health and sex education are needs to be handled most importantly in health education. 63.2% of those replied answered that appropriate time of education for health service is more than once a week. The person appropriate for health education were school nurse(63.2%). In conclusion to improve the problems of school health and to activate it, development and support of policy of health project and preparation of various conditions that can establish health courses independently is, above all, immediately required. Many efforts need to be made to make the president of schools and education authorities recognize the importance of health in schools. These efforts need to link to the transformation of awareness, and process of development of concrete method of practicing various school health education and school health is necessary.