• Journal of the Korean institute of surface engineering
• /
• v.42 no.1
• /
• pp.26-33
• /
• 2009

Recently ultra-supercritical steam power plants operate at $1000^{\circ}F$ ($538^{\circ}C$) and 3500 psi (24.1 MPa). Thermal efficiency of power plant will be increased about 2% if steam temperature increases from $1000^{\circ}F$ to $1150^{\circ}F$ ($621^{\circ}C$). In this study valve materials Incoloy901 (IC901) and Inconel718 (IN718) were nitrided to improve the surface hardness and solid lubrication function of the valve materials. The hardness of both IC901 and IN718 increased about two times by ion nitriding. IC901, IN718 and their nitrided specimens were corroded under ultra super-critical condition (USC) of $621^{\circ}C$. and 3600 psi (24.8 MPa) for 2000 hours. Oxidations of both IC901 and IN718 were very small due to the formation of protective oxide layer on the surface. But the corrosion resistance of both nitrided specimens decreased because of the formation of non-protective nitride layer of $Fe_{4}N$, $Fe_{2}N$ and CrN on the surface layer. The hardness of both nitrided IC901 and IN718 at $20{\mu}m$ depth from the surface decreased about 30% and 20% respectively by USC 2000 hours.

• Journal of the Korean association of regional geographers
• /
• v.2 no.2
• /
• pp.113-131
• /
• 1996

The purpose of this study is to identify the existence, personal characteristics and behavior of market-participants, and function of urban weekly markets in Taegu City through observation, interview and questionnaire survey. There are four weekly periodic markets such as Seongso(Monday), Chilgok(Wednesday), Siji(Thursday), and Chilgok(Friday) which have recently developed near the new apartment areas on the outskirts of Taegu. The major findings of this study can be summarized as follows: These markets originated from the agricultural cooperative's Friday markets, but were substantially established by mobile traders or merchants for the sake of their livelihood. Therefore, the existence of these markets is not explained by Stine's central place perspective but partially explained by Hay's economic locational and Bromley's socio-cultural perspective. Most traders are male, aged 30 to 40 years and have an educational level higher than high school. Most of them are living in Taegu and itinerantly visit more than two markets among the four markets by small truck. And most of them sell agricultural products and other food materials, except some who sell manufactured goods. Most consumers are housewives, aged 20 to 30 years and have an educational level higher than high school. Most of them are living within 1,000m and go there on foot. Most of them visit the markets around 3 to 5 p.m. on every market day. And they mostly buy vegetables, fruits, and fishes. Weekly markets provide employment opportunities for those who want to be merchants, and also contribute to the increase of farmers' income, because some traders(18.8%) are farmers who periodically visit markets to sell agricultural products. On the other hand, they function as a general food materials markets to neighboring residents. From these facts, both traders and consumers want weekly markets sustained. Therefore, these markets need to be protected by institutional assistance in spite of being informal markets.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.37 no.3
• /
• pp.83-92
• /
• 2019

This study aims to examine at the garden characteristics of salt merchant in Yangzhou, China during the Ming and Qing Dynasties, I looked at the background of garden formation through the literature. In addition, analyzed the garden design method and components of salt merchants. The results were as follows; First, the Yangzhou area in the past has achieved cultural and economic development with the establishment of the ancient Grand Canal. Salt merchants accumulated wealth through trade, and created many gardens under the background of securing materials for create garden through trade, forming political forces through the cultivation of students, and inflow of foreign cultures. Second, salt merchants in Yangzhou asked garden experts to design and create the garden as a place for exchange and relaxation. Also, through the production of landscape changes using Gasan(假山) and a long corridor(長廊), clear classification of spaces using architectural elements, and the placement of buildings in scenic areas adjacent to the water, the gardens with practical and aesthetic functions were owned. Third, the gardens of Yangzhou Salt Merchants have a building-oriented commercial space on the front, and a garden-centered design characteristic on the back. The garden of the commercial zone was built in a simple form using pots, oddly shaped stone, bamboo and fence patterns in the remained space, focusing on the front of the building. The garden at the back formed a curved waterway connected to the canal is refracted across the garden. The garden also features piled stones(疊石), stone bridges and ship-shaped stone building(石舫). In addition, the design reflected the introduction of trees that take into account the climate and color contrast of Yangzhou province, pavement of various materials and patterns.

• Journal of the Korean association of regional geographers
• /
• v.8 no.1
• /
• pp.65-82
• /
• 2002

This study tries to examine the characteristics of the ancient Dujiangyan Irrigation System and geographical conditions in the western part of Sichuan Basin in China. The Dujiangyan System constructed in the third century B.C is located at the mouth of gorge of the River Mi. This spot shows that its altitude above sea level is higher than that of the three other rivers in this district. Also, this river reaches the maximum discharge. These facts reveal the spot has the great potentiality as an ideal location for man-made channels. Li Bing realized the "three magical projects": Yuzui and Jinggang Dyke(a water dividing dyke), Baopingkou(a water inlet), and Feishayan(a spillway). The dyke divided the River Min into two parts. The inner river is connected to the Baopingkou. And the Feishayan discharges flood and silt from the inner river to the outer. These projects have composed a scientific irrigation and drainage network. Finally, in the Chengdu Plain were digged a dozen channels for irrigation. Some of them are connected eastward to the River Bu. Since then the Dujiangyan System has been bring great benefits to agricultural production. This resulted in the population increase and establishment of new counties which have made the plain a "Land of Abundance".

• Proceedings of the Korea Contents Association Conference
• /
• 2008.05a
• /
• pp.262-269
• /
• 2008

This research, to find the cultural identity of taekwondo, presents the historical origin of taekwondo in lights of Choi-centric theory, kwan-centric theory, karate inflow theory, and successive traditional martial arts theory. Then it investigates taekwondo's inner identity as a Korean traditional martial art according to presence, popularity, and independence, three factors of identity suggested by Tak, S. S.(2000).As a result, it reached these conclusions: First, taekwondo was formed after going through fusion of Hong Hi Choi, karate income in period of cultural severance during Japanese occupation, the first kwan leaders and Korean traditional martial arts, process of disorder and cultural reproduction. Second, taekwondo has essentially inherited and developed Korean barehanded martial arts' movements that lay stress on foot skills, and this distinguishes it from hand-skill-based Japan's karate and China's Wushu Furthermore, trunk/groin protectors and headgears are blended remarkably with taeguk patterns and traditional Colors of Five Directions. All terms rendered into pure Korean words shows the essence of Korean localization. It is therefore concluded that Koreans should, along with trying to overcome exclusive nationalism as a country of origin, build a new paradigm of establishing an identity as a global martial art sport.

• Journal of Korea Technology Innovation Society
• /
• v.18 no.4
• /
• pp.667-692
• /
• 2015

The study examined the Korean medicine industry from the perspective of the innovation system theory of each business, while it concentrated on the conflict between traditional Korean medicine and Western medicine, which have a major influence on the innovation system of Korean medicine industry, rather than the innovation system itself. The Korean healthcare system is a dual system of Western and Korean medicine, yet the definitions of Western medical practices and Korean medical practices are ambiguous. Thus the distinction of dual system depends on judicial precedents, and the innovation of Korean medicine has been inhibited due to the excessive emphasis placed on the Western medical practice in both healthcare system and pharmaceutical system. First of all, the usage of most medical devices derived from the development of modern medical engineering is not permitted in the Korean medicine industry, on the basis that most of the medical devices were originated from the Western medicine field. Secondly, new drugs using natural substances, once approved by the drug administration, cannot be prescribed by the Korean medicine industry although they are developed based on Korean medicine. Thirdly, the major safety issues on herbal medicine are about hazardous materials in medicinal herbs and liver toxicity of prescribed herbal medicine. The problem of hazardous materials can be solved by appropriate quality and safety tests in the cultivation and importation process. Whereas the Korean medicine circles points out that the liver toxicity issue is only a unilateral condemnation by the Western medicine circles.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.2
• /
• pp.261-267
• /
• 2021

The enlightenment project raised in both Korea and China during the modern period worked as a part of the patriotic enlightenment movement against the imperial powers. Among them, "boy" appeared as the subject of enlightenment, and "sea" appeared as a medium. Specifically, through "Boy Discourse," Liang Qi Chao ultimately envisioned a nation for "subjects", and Choi Nam-seon also seeked to overcome the national crisis as "New Korea" and join the ranks of powerful nations. Liang Qiqiao proposes the concept of a "Boy Nation" and an "Old Nation" through boy discourse, and wishing for the development of the "Boy Nation" through "proficiency training". Choi Nam-seon also recognized that the future of the nation depends on "boys", influenced by Liang Qi-qiao's discourse on boys, and argues that Choseon should cultivate skills to become a "Boy Nation". In addition, Liang Qi-chao and Choi Nam-seon actively spread the "boy discourse" through the creation of poetry. Liang Qi Chao introduced the world's geography and history through poetries related to the sea, while at the same time inspiring a sense of challenge to recognize and pioneer the sea as a pathway that connects the world in a broad sense. Namseon Choi also created a poem that directly linked "the sea" and the "boy" to promote the "adventure at sea" and "the progressive spirit of the sea and the boy".

• Food Science and Industry
• /
• v.52 no.3
• /
• pp.272-286
• /
• 2019

Cheesemaking is believed to have been first practiced in prehistoric times, about 9,500 years ago, in the area around the Fertile Crescent of Mesopotamia and they left legacy in the name of cheese. Father Chi Chong-Hwan(Didier Serstevens) started for his provost in Imsil Catholic church in 1964. In 1968, cheese was first produced Camembert in Korea by Father Chi Chong-hwan, and then made Mozzarella in 1970, Cheddar in 1972. Father Chi lay the foundation of a cheese industry in Korea. The processed cheese market was highly grown after putting on the market of sliced cheese in the late 1980s, and the various products that complied with wellbeing trends such as organic and high functional cheese produced in the 2000s. The natural cheese opens up a new domestic market after producing Camembert and Brie cheese in the end of 2004. At present, major trends in cheese are authenticity, bold flavor, snack sophistication and tradition. Mozzarella, Parmesan, Cheddar, Provolone, Feta cheese still top in foodservice. In Korea, production of natural cheese is decreasing by the influence of the imported cheese. Production of processed cheese is increasing and total consumption of cheese is also increasing year by year.

• Journal of the Korean Society of Radiology
• /
• v.15 no.1
• /
• pp.37-43
• /
• 2021

Republic of Korea has many nuclear facilities in the country, and Democratic People's Republic of Korea(North Korea) locates in the surrounding country. Therefore, it is necessary to construct the target facility's nuclear forensic data in a preemptive response to the changing international situation. For this reason, this study suggests "signature" materials used to understand the origins and sources of nuclear and other radioactive materials, taking into account domestic nuclear facilities and the nuclear fuel cycle. In domestic, pressurized light water reactors and pressurized heavy water reactors are in operation, and enriched and natural uranium are used as fuels. In the front-end fuel cycle, the signature materials can be nature uranium and UF6 in the uranium enrichment process. The domestic back-end fuel cycle adopts a non-circulating cycle excluding the reprocessing process, and the primary signature material is spent nuclear fuel. According to IAEA recommendation, the importance of these materials as the signature and characteristic contents are suggested in this study. To prove the integrity of nuclear material and build a national nuclear forensics library, it is necessary to grasp the signature material and acquire the characteristic data considering the domestic nuclear facilities and the nuclear fuel cycle.

• Journal of The Korean Association For Science Education
• /
• v.40 no.6
• /
• pp.671-685
• /
• 2020

The purpose of this study is to critically examine the relationship between 'academic disciplines', 'subject', 'subject content', and 'subject matter education' as an attempt to explore the meaning and identity of subject matter education. In this study, first, we looked at the origin of the 'separative' perspective, focusing on science education, and the effects of this perspective on the relationship between 'academic discipline', 'subject', 'subject content', and 'subject matter education'. In addition, the relationship between them was examined from 'essential-holistic' perspective. As a result of the study, it was found that the 'separative' perspective has limitations in grasping the organic and overall relationship between 'academic discipline', 'subject', 'subject content', and 'subject matter education'. Therefore, we need to overcome the existing 'separative' perspective in order to go beyond the current horizon. On the other hand, the 'essential-holistic' perspective shows a close relationship that is not essentially separated between 'academic discipline', 'subject', 'subject content', and 'subject matter education'. It is expected as a perspective that can help solve the teacher education problem caused by the 'separative' perspective.