• Title/Summary/Keyword: 도성

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A Study on the Capital City, Chang'an's(長安), Water System (수당(隋唐) 장안성(長安城)의 도성 형식과 수체계에 관한 연구)

  • Park, Hee-Soung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.39 no.5
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    • pp.127-140
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    • 2011
  • The research described in this report was conducted to find out how elements of the natural environment contributed to the formation of Chang'an, how its water system reinforced its status as the capital city, and what role it took for its urban function based on studies of the canal constructions. During the period of Sui and Tang, Chang'an built a sophisticated water system using Qu(渠), the irrigation facilities. In the water system, hills are called Yuan(原), and rivers with the proper environment to be developed plan into urban infrastructure facilities for irrigation water, urban living water, the composition of garden-based facility, reservoirs, and others. They improve agricultural productivity and, consequently, increase the city's competitiveness as well as contributing to the urban infrastructure, serving as a convenient source and ensuring the quality of life was abundant. So, the urban effects of the water system have raised the capital's status. With the contribution of its pragmatic water system, Chang'an not only performed its urban function brilliantly, but also established itself more firmly as a capital city.

고 분산성 자성 나노유체의 열전도도 및 점성

  • Seo, Yong-Jae;Lee, Hyo-Suk;Jo, Guk;Gil, Dae-Seop;Jeong, Gyeong-U;Ju, Myeong-Eun
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2010.05a
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    • pp.4.2-4.2
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    • 2010
  • 최근 열전달율을 획기적으로 향상시킬 수 있는 고 열전도성 나노유체가 주목을 받고 있다. 고 열전도성 나노유체는 액상보다 열전도도가 수백~수만 배 높은 고상의 금속 또는 비금속 나노입자를 물이나 오일 등에 미량 균일하게 분산시킴으로써 기존의 유체가 가지지 못한 높은 열전도율과 분산안정성을 갖는 기능성유체를 말한다. 고 열전도성 나노유체는 기존 냉각시스템에서 냉각유체만 교체할 경우에도 열전달 효율을 20% 이상 향상시킬 수 있는 저비용 고효율작동 유체이다. 이 나노유체는 발전설비, 공조설비, 에너지 산업, 석유화학, 화학공업, 제철산업, 가정용 냉난방설비, 자동차 등 산업 전 분야의 열교환시스템에 활용이 가능하다. 따라서 고 열전도성 나노유체는 종래 열효율의 한계를 돌파할 수 있는 에너지 이용 효율 향상 기술의 패러다임을 바꿀 혁신적인 신소재로 여겨지고 있다. 그러나 현재까지 개발된 나노유체는 초기 열전도 특성은 우수하나 장기간 분산안정성이 확보되지 않아 시간이 경과함에 따라 열전도도가 점점 감소하는 경향을 보인다. 또한 탄소나노튜브를 분산한 나노유체의 경우와 같이 유체의 점도가 크게 증가하여 실제 산업에 적용 시 커다란 동력손실을 초래할 수 있으며 열교환시스템에 파울링이 발생할 소지가 크다. 이러한 문제점을 해결하기 위해서는 나노유체에서 열전달이 일어나는 메커니즘이 규명되어야 하지만 아직 명확한 이론이나 가설이 정립되어 있지 않다. 이 논문에서는 나노유체가 높은 열전도율을 보이는 현상을 설명할 수 있는 몇 가지 이론을 살펴 보고 지금까지 개발된 안정성이 아주 높은 나노유체의 열전도 특성을 비교 분석하여 획기적인 열전도성 나노유체 개발 가능성을 살펴보고자 한다. 이를 위해 나노입자의 조성, 유체 내 농도 및 자기장 등이 나노유체의 열전도율에 미치는 영향을 연구하였다.

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Development of a process for the implementation of fine electronic circuits on the surface of nonconductive polymer film (비전도성 폴리머 필름 표면상에 미세 전자회로 구현을 위한 공정개발)

  • Jeon, Jun-Mi;Gu, Seok-Bon;Heo, Jin-Yeong;Lee, Chang-Myeon;Lee, Hong-Gi
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2017.05a
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    • pp.121-121
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    • 2017
  • 본 연구는 비전도성 폴리머 표면을 개질하여 감광성 금속을 유전체 표면에 흡착시키고, 감광성 금속의 광화학 반응을 이용하여 귀금속 촉매를 비전도성 폴리머 표면에 선택적으로 흡착시켜 무전해 Cu 도금을 수행하여 금속패턴을 형성하였다. 기능성 유연 필름은 일반적으로 투명한 플라스틱 고분자 기판을 기반으로 전기 전자, 에너지, 자동차, 포장, 의료 등 다양한 분야에서 폭넓게 활용 되고 있으며, 본 연구에서는 습식 도금 공정을 이용하여 폴리이미드 필름상에 $10{\mu}m$ 이하의 미세패턴을 형성하기 위한 공정을 개발하고자 하였다. 비전도성 폴리머 표면에 무전해 도금을 위해서 우선 폴리머 필름의 표면을 개질하는 공정이 필요하다. 이에 KOH 또는 NaOH 알카리 용액을 이용하여 표면을 개질하였으며 개질된 표면에 감광성 금속이온의 흡착시키기 위한 감광성 금속이온은 주석을 사용하였으며, 주석 용액의 안정성 및 퍼짐성 향상을 위해 감광성 금속 용액의 제조 및 특성을 관찰하였으며, 감광성 금속화합물이 흡착된 비전도성 유전체 표면을 포토마스크를 이용하여 특정 부위, 즉 표면에 금속패턴 층을 형성하고자 하는 곳은 포토마스크를 이용하여 광원을 차단하고 그 외 부분은 주 파장이 365nm와 405nm 광원을 조사하여 선택적으로 감광성 금속화합물의 산화반응을 유도하는 광조사 공정을 수행하였다. 광원이 조사되지 않은 부분에 귀금속 등의 촉매 입자를 치환 흡착시켜 금속 패턴이 형성될 수 있는 표면을 형성하였다. 위의 활성화 공정이후에 활성화 처리된 표면을 세척하는 수세 공정을 거친 후 무전해 도금공정에 바로 적용할 경우 미세한 귀금속 입자가 패턴이 아닌 부분 즉 자외선(UV) 조사된 부분에도 남아있어 도금시 번짐 현상이 발생한다. 이에 본 연구에서는 활성화 처리 후 약 알칼리 용액에 카르복실산을 혼합하여 잔존하는 귀금속 입자를 제거한 후 무전해 Cu 도금액을 이용하여 $10{\mu}m$ 이하의 Cu 금속 패턴을 형성하였다.

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The Effect of Warm Scarf on Postoperative Xerostomia and Sore Throat in Colon Cancer Patients (대장암 수술 후 온열 목 마스크 적용이 구강건조와 인후통에 미치는 효과)

  • Choi, Song Yi;Lee, Ga Eun;Yoon, Bo Ra;Yoon, Ji Sun;Chung, Seo Young
    • Journal of Korean Clinical Nursing Research
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    • v.29 no.1
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    • pp.67-74
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    • 2023
  • Purpose: This study aimed to identify the effect of warm scarf on xerostomia and sore throat in postoperative colon cancer patients. Methods: A total of 40 participants with colon cancer who underwent colon cancer operation over 2hours were included from C University hospital in Seoul. The number of experimental group and control group is each 20 calculated by G*Power, and they were assigned by using nonequivalent control group no-synchronized design. In the experimental group, a warm scarf was applied to the neck for 120 minutes from entering the recovery room after the colorectal cancer surgery was completed. In the experimental group and the control group, xerostomia and sore throat were measured twice at 60-minute intervals. The degree of xerostomia was measured through the degree of wetness of the absorbent paper in mm, and the degree of sore throat was measured through the NRS (Numeral Rating Scale). Data were collected using self-administered questionnaires from August 2018 to September 2020 and were analyzed using IBM SPSS/WIN 21.0 Descriptive statistics, x2 test, Fisher's exact test, t-test were used to determine the participant's characteristics. The effect of warm scarf on xerostomia and sore throat were separately estimated by Repeated Measures ANOVA. Results: The experimental group showed significant decrease of xerostomia and sore throat as time goes (p<.001). Conclusion: Results indicate that warm scarf on xerostomia and sore throat in postoperative colon cancer patients is helpful method for relieving side effect of tracheal intubation.

Collision of New and Old Control Ideologies, Witnessed through the Moving of Jeong-regun (Tomb of Queen Sindeok) and Repair of Gwangtong-gyo (정릉(貞陵) 이장과 광통교(廣通橋) 개수를 통해 본 조선 초기 지배 이데올로기의 대립)

  • Nam, Hohyun
    • Korean Journal of Heritage: History & Science
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    • v.53 no.4
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    • pp.234-249
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    • 2020
  • The dispute involving the construction of the Tomb of Queen Sindeok (hereinafter "Jeongreung"), King Taejo's wife in Seoul, and the moving of that tomb, represents the most clearly demonstrated case for the collision of new and old ideologies between political powers in the early period of Joseon. Jeongreung, the tomb of Queen Sindeok from the Kang Clan, was built inside the capital fortress, but in 1409, King Taejong forced the tomb to be moved outside the capital, and the stone relics remaining at the original location were used to build the stone bridge, Gwangtong-gyo. In an unofficial story, King Taejong moved the tomb outside the capital and used the stone items there to make the Cheonggyecheon Gwang-gyo so that the people would step upon the area in order to curse Lady Kang. In the final year of King Taejo, Lady Kang and King Taejong were in a politically conflictual relationship, but they were close to being political partners until King Taejo became the king. Sillok records pertaining to the establishment of Jeongreung or Gwangtong-gyo in fact state things more plainly, indicating that the moving of Jeongreung was a result of following the sangeon (a written statement to the king) of Uijeongbu (the highest administrative agency in Joseon), which stated that having the tomb of a king or queen in the capital was inappropriate, and since it was close to the official quarter of envoys, it had to be moved. The assertion that it was aimed at degrading Jeongreung in order to repair Gwangtong-gyo thus does not reflect the factual relationship. This article presents the possibility that the use of stone items from Jeongreung to repair Gwangtong-gyo reflected an emerging need for efficient material procurement that accompanied a drastic increase in demand for materials required in civil works both in- and outside the capital. The cause for constructing Jeongreung within the capital and the cause of moving the tomb outside the capital would therefore be attributable to the heterogeneity of the ideological backgrounds of King Taejo and King Taejong. King Taejo was the ruler of the Confucius state, as he reigned through the Yeokseong Revolution, but he constructed the tomb and Hongcheon-sa, the temple in the capital for his wife Queen Sindeok. In this respect, it is considered that, with the power of Buddhism, there was an attempt to rally supporters and gather the force needed to establish the authority of Queen Sindeok. Yi Seong-gye, who was raised in the Dorugachi clan of Yuan, lived as a military man in the border area, and so he would not have had a high level of understanding in Confucian scholarship. Rather, he was a man of the old system with its 'Buddhist" tendency. On the other hand, King Taejong Yi Bang-won was an elite Confucian student who passed the national examination at the end of the Goryeo era, and he is also known to have held a profound understanding of Neo-Confucianism. To state it differently, it would be reasonable to say that the understanding of symbolic implications for the capital would be more profound in a Confucian state. Since the national system that was ruled by laws had been established following the Three-Kingdom era, the principle of burial outside of the capital that would have seen a grave constructed on the outskirts of the capital was not upheld, without exception. Jeongreung was built inside the capital due to the strong individual desire of King Taejo, but since he was a Confucian scholar prior to becoming king, it would not have been accepted as desirable. After taking the throne, King Taejong took the initiative to begin overhauling the capital in order to reflect his intent to clearly realize Confucian ideology emphasizing 'Yechi' ("ruling with good manners") with the scenic view of the Capital's Hanyang river. It would be reasonable to conclude accordingly that the moving of Jeongreung was undertaken in the context of such a historic background.

Ecophysiological Interpretations on the Water Relations Parameters of Trees (X) - The Characteristics of Relative Conductivity in the Twenty-one Deciduous Broad-Leaved Species - (수목(樹木)의 수분특성(水分特性)에 관(關)한 생리(生理)·생태학적(生態學的) 해석(解析)(X) - 낙엽(落葉) 활엽수(闊葉樹) 21종(種)의 상대수분통도성(相對水分通導性)의 비교(比較) -)

  • Han, Sang Sup;Kim, Sun Hee;Yi, Myong Jong
    • Journal of Korean Society of Forest Science
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    • v.87 no.1
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    • pp.90-97
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    • 1998
  • This study was carried out to compare the characteristics of relative conductivity(RC) in the twenty-one deciduous broad-leaved species. The results obtained were summarized as follows : 1. The RC ranged from $3.18{\times}10^{-15}$ to $1.23{\times}10^{-10}m^2$ in deciduous broad-leaved species, and appeared different values in various portions of a tree and species. 2. In eight diffuse-porous species, the ranges of average RC were $3.49{\times}10^{-13}$ to $6.35{\times}10^{-11}m^2$ in stems. $4.89{\times}10^{-13}$ to $2.99{\times}10^{-11}m^2$ in branches, and $1.33{\times}10^{-13}$ to $9.42{\times}10^{-12}m^2$ in junction part between stem and branch. In thirteen ring-porous species, the RCs were $7.14{\times}10^{-13}$ to $4.76{\times}10^{-11}m^2$ in stems, $2.93{\times}10^{-13}$ to $3.91{\times}10^{-11}m^2$ in branches, and $1.14{\times}10^{-13}$ to $9.20{\times}10^{-12}m^2$ in junction part. 3. The RC and diameter of stem have no interrelation in eight diffuse-porous species. The RC of stem increased with decreasing diameter of stem in eleven ring-porous species except Fraxinus mandshurica and Maackia amurensis. 4. In five deciduous broad-leaved species, the RC of 1-year-old shoots(the leader and adjacent laterals ) ranged from $4.87{\times}10^{-13}$ to $8.41{\times}10^{-11}m^2$ in the leaders, and $7.93{\times}10^{-14}$ to $2.01{\times}10^{-11}m^2$ in the adjacent laterals. The RCs were much greater in the leaders than in the adjacent laterals because of the hydraulic dominance of the leader shoot.

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Effect of Non-Conducting Filler Additions on Anisotropic Conductive Adhesives(ACAs) Properties and the Reliability of ACAs Flip Chip on Organic Substrates (이방성 전도 접착제 물성과 유기 기판 플립 칩의 신뢰성에 미치는 비전도성 충진재의 영향)

  • Im, Myeong-Jin;Baek, Gyeong-Uk
    • Korean Journal of Materials Research
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    • v.10 no.3
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    • pp.184-190
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    • 2000
  • We investigated the effect of filler content on the thermo-mechanical properties of modified ACA composite materials by incorporation of non-conducting fillers and the reliability of flip chip assembly on organic substrates using modified ACA composite materials. For the characterization of modified ACA s composites with different content of non-conducting fillers, differential scanning calorimeter (DSC), and thermo-gravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), and thermo-mechnical analyzer (TMA) were utilized. As the non-conducting filler content increased, CTE values decreased and storage modulus at room temperature increased. In addition, the increase in the content of filler brought about the increase of Tg^{DSC}$ and $Tg^{TMA}$. However, the TGA behaviors stayed almost the same. Contact resistance changes were measured during reliability tests such as thermal cycling, high humidity and temperature, and high temperature at dry condition. It was observed that reliability results were significantly affected by CTEs of ACA materials especially at the thermal cycling test. Results showed that flip chip assembly using modified ACA composites with lower CTEs and higher modulus by loading non-conducting fillers exhibited better contact resistance behavior than conventional ACAs without non-conducting fillers.

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Analysis of Ancient Document and Establishment of Petrological Database for Presumption of Stone Source Area of the Seoul City Wall, Korea (한양도성 석재공급지 추정을 위한 고문헌 분석 및 암석학적 데이터베이스 구축)

  • Jo, Young Hoon;Lee, Chan Hee
    • The Journal of the Petrological Society of Korea
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    • v.24 no.3
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    • pp.193-207
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    • 2015
  • This study analyzed ancient documents and established petrological database through extensive field investigation of provenance sites to presume stone source areas of the Seoul City Wall. By summarizing the ancient documents, the rampart stone was mostly supplied from a stony mountain adjacent to the City Wall in the early Joseon period, whereas the stone was provided from fixed quarry outside the City Wall in the late Joseon period. As a result of the petrological investigation based on quarries recorded in the ancient documents, pinkish granite and leucogranite were distributed as a whole, and the granitoid rocks are similar in mineralogical compositions and geochemical behavior characteristics. However, the pinkish granite with magnetic-series show that the magnetic susceptibility increased from the north slope of Namsan Mountain to Bulamsan Mountain. The leucogranite with ilmenite-series mainly occurred along the boundary between granite and gneiss from Yongmasan Mountain to Inwangsan Mountain. Consequently, the important petrological indicators for presumption of stone source areas are the rock color and the magnetic susceptibility. In addition to the petrological features, the reliability for provenance interpretation should improve considering stone quantities in the quarries, transportation distance and technical skills.

Study on the Superconducting Region in the Ternary Phase Diagram for the $Y_2O_3-BaO-CuO$ System ($Y_2O_3-BaO-CuO$ 3성분계 상도에서의 초전도 영역에 관한 연구)

  • 조성래;장민수;김정남;노지현;김형국
    • Electrical & Electronic Materials
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    • v.2 no.1
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    • pp.65-75
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    • 1989
  • 22종류의 Y-Ba-Cu-O계 세라믹스의 초전도성을 조사하기 위하여 x-선 회절무늬, 전기/저항 및 적외선 투과도를 측정하였다. 또한 시료의 제조 조건에 따른 영향도 조사하였다. 측정결과 3성분게 상도에서 넓은 영역에 걸쳐 초전도성이 나타났으며 특히 상도의 중앙부근의 조성을 갖는 시료들은 실온에서 전기 저항값이 작고 90K이상에서 초전도 전이가 일어남을 알 수 있었다.

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Development of Conductive-Corrosion Resistive Stainless Steel for PEMFC Bipolar plate (고분자전해질 연료전지용 스테인리스 분리판 고내식/고전도성 표면개질 기술 개발)

  • Han, Jun-Hui;Jeong, Yeon-Su;Jeon, Yu-Taek
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2014.11a
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    • pp.278-278
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    • 2014
  • 저가형 고전도성/고내식 연료전지용 금속분리판 제작을 위해 다양한 조성 및 온도에서 표면개질을 시행하였다. 본 연구에 의해 제작된 시편의 표면분석 결과 Fe 선택적 용출 및 Cr-rich layer 형성이 이루어졌음을 확인하였으며, 성능 평가 결과 2015 DOE 목표를 만족시키는 것을 확인하였다.

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