• 공업화학
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• 제22권3호
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• pp.243-248
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• 2011

상온에서 작동하는 고감도 수소 가스센서를 제조하기 위하여 Pt 촉매가 증착된 다공성 탄소나노섬유를 제조하였다. 나노섬유는 polyacrylonitrile을 탄소전구체로 하여 전기방사법을 이용하여 제조되었고, 탄소나노섬유의 제조를 위하여 열처리 공정을 거쳤다. 다음으로, 탄소나노섬유에 화학적 활성화 공정을 통하여 가스 흡착을 위한 높은 비표면적과 기공구조를 부여하였다. Pt는 수소가스에 대한 촉매효과를 위하여 스퍼터링법을 통해 다공성 탄소나노섬유에 증착되었다. 탄소나노섬유는 화학적 활성화 공정을 통해 비표면적이 $2093m^2/g$으로 100배 이상 증가하였고, 약 60 vol%의 미세기공이 부여되었다. Pt는 다공성 탄소나노섬유의 형태를 그대로 유지하면서 얇고 고르게 증착되었다. 제조된 가스센서의 반응속도와 민감도는 비표면적, 미세기공율의 증가와 Pt 증착에 의하여 증가하였다. 결과적으로 수소가스에 대한 탄소나노섬유 상온에서 감응특성은 화학적 활성화와 Pt의 촉매효과에 의하여 향상됨을 알 수 있었다.

• 융합정보논문지
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• 제11권6호
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• pp.146-153
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• 2021

최근 페로브스카이트 반도체 물질에 대한 연구가 이루어지고 있고, 이 물질에 대한 표면 처리를 이용한 특성 평가는 후속 연구들의 기반이 된다. 따라서, 본 논문에서는 상압분위기에서 플라즈마가 형성되는 상압플라즈마 장비로 산소 플라즈마를 생성하여 공기중에 약 6개월정도 노출시킨 페로브스카이트 박막을 표면 처리한 결과에 대해 연구하였다. 6개월간 노출시킨 이유는 페로브스카이트 박막은 유기물과 무기물로 이루어져 있기 때문에 공기 중에 노출되면, 산소나 수증기와의 반응을 통해 표면이 변화된다. 따라서, 이러한 변화를 원래 막으로의 복원이 가능한지 알아보기 위함이다. 산소플라즈마 분위기에서 1초부터 1200초까지 공정 시간을 변화시켜 가면서 표면 형상과 원소들 비율을 분석하였다. 이러한 결과는 페로브스카이트 막이 시간에 따라 변화가 일어나더라도 플라즈마 처리를 통해 이를 해결하는 방안을 제공한다.

• 구강회복응용과학지
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• 제37권4호
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• pp.251-258
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• 2021

치아 외상은 어린이와 비교적 젊은 연령에서 흔히 발생하며 외상 발생 시점, 환자의 나이, 치아의 성숙 상태 등이 치료 방법에 영향을 미친다. 약 파절편이 건전하고 잔존 치아와 밀접한 적합을 보일 경우, 파절편 재부착은 유용한 치료 옵션이 될 수 있다. 이 방법은 치아 본래의 형태와 교합의 회복뿐만 아니라 기능, 표면 광택과 질감을 그대로 재현할 수 있는 여러 가지 이점이 있다. 본 증례보고는 복잡 치관 파절된 치아를 섬유 강화형 포스트를 활용하여 파절편 재부착을 시행한 두 증례에 대해 소개한다.

• 한국엔터테인먼트산업학회논문지
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• 제14권2호
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• pp.85-95
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• 2020

악기(樂器)는 음악을 연주하는 데 쓰이는 기구로서 뿐만 아니라 음악적, 역사적 또는 사회적 맥락에서의 의미를 함축하고 있다. 양금은 사다리꼴 모양의 몸통 위에 줄을 괘에 얹어 채를 이용하여 현을 쳐서 연주하는 타현악기(打絃樂器)로 고대 아라비아와 페르시아에서 기원하여 세계 여러 지역에서 창조적으로 계승되어 연주되고 있다. 본 논문에서는 형태나 연주법의 변화 없이 원형의 모습을 그대로 간직하고 있는 한국 전통양금을 음악도상학(音樂圖像學, Musical Iconography)적 연구 방법을 통해 악기에 함축되어 있는 의미를 고찰하고자 한다. 본 연구가 악기연구에 대한 새로운 관점을 제시하고 악기 본연의 이해를 높일 뿐만 아니라 악기가 함축하고 있는 의미를 이해하는 데 도움이 될 수 있기를 기대해본다. 음악도상학적 방법을 통한 연구를 통해 악기연구가 보다 다층적인 면에서 활성화되고 음악학의 영역이 더욱 폭넓은 측면에서 다루어지기를 바라는 바이다.

• 대한본초학회지
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• 제33권2호
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• pp.29-43
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• 2018

Objectives : Araliae Continentalis Radix(AC) is a medicinal herb belonging to the drug efficacy group treating musculoskeletal disorders(MSD) with anti-inflammatory, analgesic and antipyretic action. However, due to morphologic and onomastic similarity, adulterants(Angelicae Pubescentis Radix: AP, Gypsophilae Oldhamianae Radix: GO, Levistici Officinalis Radix: LO) have been included or replaced the standard. Methods : Multilateral methods were carried out on the identification of AC and its adulterants. Macroscopic and microscopic characteristics were observed by using stereoscope and microscope. For the comparison of chromatogram pattern, standard compounds were analyzed simultaneously using high performance liquid chromatography. Results : 1. The macroscopic identification of original plants was determined by the phyllotaxis type, the inflorescence type, the leaf margin and the color of flowers. The macroscopic identification of herbal materials was examined by oil spots, the cambium, heteromorphic vascular bundles, and the pholem. 2. For the microscopic identification, the fact whether its xylem ray is proliferated or not was first determined. Then medicinal herbs were secondly divided by cellular inclusions, fiber bundles, the distribution of secretary canals and the shape of cambium. 3. AC and its adulterants showed different chromatographic fingerprints. AC was containing continentalic acid and kaurenoic acid. AP was containing osthole and columbianadin. LO was containing osthole and falcarindiol. None of the compounds were found in GO. Conclusions : This recent identification keys of might be helpful to discriminate the pharmacopoeia standard and its adulterants for the right usage in clinics.

• 대한본초학회지
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• 제34권6호
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• pp.63-70
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• 2019

Objective : Arnebiae Radix, the roots of Arnebia euchroma (Royle) Johnst. or A. guttata Bunge, is a well-known traditional herbal medicine in East Asia. In the Korean Pharmacopoeia, three authentic species, including two Arnebia and Lithospermum erythrorhizon Sieb. et Zucc. have recognized as a Lithospermi Radix. But, the morphological and taxonomic information of two authentic Arnebia species lacks date since their distribution and difficulty of accessing the natural habitats. Methods : A full description of the external morphological characteristics of vegetative and reproductive organs in the original plants was carried out using digital calipers and stereoscope. For providing their taxonomic and nomenclatural synonyms, we reviewed various plant checklists and taxonomic literature. Results : This study provides taxonomic information of A. euchroma and A. guttata based on a morphological examination of authentic plant individuals and field observations. Detailed descriptions of the two Arnebia species, major quantitative and qualitative characteristics, nomenclatural reviews, distribution maps, and lists of voucher specimens examined are provided. The shape of leaves, root length, stem number, calyx length and pubescence as well as corolla color were useful characteristics for identification. Moreover, we confirmed that A. euchroma and A. guttata are clearly heterostylous species. Conclusion : Our research provides valuable basic information that could be used as quality control for distinguishing between Arnebiae Radix and its adulterants. These results will help in the understanding of authentic plants and also provide the verified materials and voucher information.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1421-1430
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• 2022

The computation of the solid angle and the detector efficiency is considering to be one of the most important factors during the measuring process for the radioactivity, especially the cylindrical γ-ray NaI(Tl) detectors nowadays have applications in several fields such as industry, hazardous for health, the gamma-ray radiation detectors grow to be the main essential instruments in radiation protection sector. In the present work, a generic numerical simulation method (NSM) for calculating the efficiency of the γ-ray spectrometry setup is established. The formulas are suitable for any type of source-to-detector shape and can be valuable to determine the full-energy peak and the total efficiencies and P/T ratio of cylindrical γ-ray NaI(Tl) detector setup concerning the truncated conical radioactive source. This methodology is based on estimate the path length of γ-ray radiation inside the detector active medium, inside the source itself, and the self-attenuation correction factors, which typically use to correct the sample attenuation of the original geometry source. The calculations can be completed in general by using extra reasonable and complicate analytical and numerical techniques than the standard models; especially the effective solid angle, and the detector efficiency have to be calculated in case of the truncated conical radioactive source studied condition. Moreover, the (NSM) can be used for the straight calculations of the γ-ray detector efficiency after the computation of improvement that need in the case of γ-γ coincidence summing (CS). The (NSM) confirmation of the development created by the efficiency transfer method has been achieved by comparing the results of the measuring truncated conical radioactive source with certified nuclide activities with the γ-ray NaI(Tl) detector, and a good agreement was obtained after corrections of (CS). The methodology can be unlimited to find the theoretical efficiencies and modifications equivalent to any geometry by essential sufficiently the physical selective considered situation.

• 복식문화연구
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• 제30권6호
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• pp.799-813
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• 2022

The environment has increasingly attracted attention and fashion brands need to use new growth models by developing eco-friendly products, along with the drastic climate change. This study drew design guidelines from the factors of clothing disposal and reuse to propose ways to extend the longevity of clothing. It sets the design goals for the longevity extension of clothing as flexibility, originality, durability, and adjustability and drew a specific design guideline. The design methods used to achieve such goals are as follows. First, the design that is flexible in terms of physical changes needs to increase its activity and to be changeable, by applying pleats, rubber bands and elastic materials to the parts with many physical changes and movements. Second, it is necessary to reinforce the brand identity, create design that is flexible in terms of fashion and design very rare and attractive products, for the goal of original design beyond fashion. Third, it is necessary to increase the quality of clothing and improve the durability which can be decreased by washing and wearing. Fourth, it is necessary to create the design that can produce various styles, preserve the state of clothing and maintain its hygienic conditions by using removable detailed designs, shape-transformation designs and the designs which can be adjusted to climate changes and states, for the goal of adjustable design with better functionality. The findings provide ideas for fashion experts to pay more attention to the extending the longevity of clothing products and to develop eco-friendly designs and strategies.

• Composites Research
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• 제19권2호
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• pp.28-34
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• 2006

고온자전합성법과 스파크 플라즈마 소결법으로 여러 가지 $TiB_2$ 함유량을 갖는 $Cu-TiB_2$ 금속복합재료를 제조하였다. 점용접 전극과 미끄럼 접촉재로 사용하기 위해 인장특성, 경도, 마모저항 등의 물성치를 조사하였다. 강화재의 형상, 크기, 부피분율 등에 의해 복합재료의 특성이 달라지므로 유효물성치를 예측하기 위한 모델링이 필수적이다. 유한요소해석결과 유효탄성 계수가 실험치와 일치하는 것을 확인하였고 Eshelby 모델, Mori-Tanaka의 평균장 이론이 결합된 Eshelby 모델, 혼합법칙 등으로 복합재료의 탄성계수를 예측한 결과 Mori-Tanaka의 평균장 이론이 결합된 Eshelby 모델이 실험치를 사장 잘 묘사하는 것으로 나타났다.

• 한국의상디자인학회지
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• 제25권2호
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• pp.1-16
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• 2023

Due to the current seriousness of environmental pollution and the eco-friendly movement of the fashion industry, research on sustainable fashion design is being actively conducted. In this study, consumer perception of upcycling products, are divided into image, function, and meaning; and image is further divided into shape, color, and material. It was redefined as pattern, and image recognition was evaluated among men and women in their 20s and 30s, and men and women in their 40s and 50s used as subjects. First, factors that determine each image were extracted based on qualitative analysis of the precedent cases of upcycling bags, and quantitative analysis of the subjects was induced through a questionnaire. As a result of the analysis of evaluation items related to image association, the average frequency analysis of all subjects for each stimuli and the cognitive variance of the frequency analysis by generation by gender were found to be similar. However, awareness of some stimuli by generation showed a significant difference. Overall, in the three stimuli with high overall preference, common features, such as the basic box-shaped symmetrical structure, the monochromatic color of the Munsell system, solid and practical texture, and appropriate use of patterns were identified. In addition, it was confirmed that there was a difference with factors such as femininity, simplicity, touch, and splendor in the measurement factors. In conclusion, it is considered that the main significance of this study is that it excluded the recognition and meaning of upcycling products and explored the original design and image elements of products. Therefore, it is expected that this study will be used as a basic data for responding to the gender image of each generation as an alternative method of sustainable fashion design, and it will be an opportunity to expand the scope of the study to a detailed study beyond the biased topic.