원장현류 대금산조 연구

서정미 전북대학교 일반대학원 2019 국내박사

In this study, melodies of Won, Jang-hyun style Daegeum Sanjo, Kim, Dong-jin style Daegeum Sanjo short melody that laid foundation for Won, Jang-hyun style, and Han, Il-seup style Daegeum Sanjo that had been passed down verbally to Han, Ju-hwan were comparatively analyzed to find the same melody and similar melody and to draw creative melody which appeared only in Won, Jang-hyun style Daegeum Sanjo. I also tried to analyze the mode and scale unique to Won, Jang-hyun style Daegeum Sanjo melody through melody analysis. The results are as follow. First, the results of comparative analysis of melody by movements are as follows. ① Jinyangjo movement was composed of b♭ primary key Woojo-gil, a mixture of sol scale and la scale, e♭ primary key Woojo-gil of sol scale, and Gaemeongil melody of me scale with three primary keys of c, f, and b♭. ② Jungmori movement was composed of b♭ primary key Woojo-gil, a mixture of sol scale and la scale, and Gaemeon-gil melody of mi scale with c primary key. ③ Jungjungmori movement was composed of b♭ primary key Woojo-gil, a mixture of sol scale and la scale, b♭ primary key Gyeongdeureum of sol scale, and Gaemeon-gil melody of mi scale with three primary keys of g, c, and f. ④ It was found that Jajinmori movement was composed of b♭ primary key Woojo-gil, a mixture of sol scale and la scale, e♭ primary key of Woojo-gil of sol scale, two primary keys of c and f of Gaemeon-gil of mi scale, and Deolleongjae melody of la scale. Therefore, Won, Jang-hyun style Daegeum Sanjo was mostly composed of Gaemeon-gil and Woojo-gil without Pyeongjo-gil melody. Woojo-gil which appeared in all movements was composed of a mixture of sol scale and la scale, and Gaemeon-gil key of mi scale was composed of three types primary keys of c, f, and b♭ in Jinyangjo movement. Jungmori movement was composed of one type of c primary key, Jungjungmori movement was composed of three primary keys of c, f, g, and Jajinmori movement was composed of two primary keys of c and f. Aslo, Gyeongdeureum melody, which was turned into pansori by master singer Yeom, Gae-dal utilizing Gyeonggi Sori Music language mode, was in Jungjungmori movement, and Deolleongjae melody, which was turned into pansori by master singer Kwon, Sam-deuk utilizing KwonMaseung melody from Youngsanhaesang martial music, was in Jajinmori movement. Second, Won, Jang-hyun style Daegeum Sanjo melody were compared to Han, Ju-hwan style Daegeum Sanjo and Kim, Dong-jin style Daegeum Sanjo melody according to the change of mode and key (cheong) to find same melody and similar melody and the result of finding the unique melody of Won, Jang-hyun style are as follows. ① In Jinyangjo movement there were b♭ primary key Woojo-gil melody of in 19 Jangdangs, and out of them, 14 Jangdans (74%) were same melodies and 5 Jangdans (26%) were similar melodies to Han, Ju-hwan and Kim, Dong-jin stlye Daegeum Sanjo melody. In addition, e♭ primary key Woojogil melody had 2 Jangdans which were found to be similar melody. Therefore, in Woojo-gil melody in Jinyangjo movement, there was no creative melody. Although Gaemeon-gil melody appeared in 3 primary keys of c (40 Jangdans), f (14 Jangdans), and b♭ (5 Jangdans) in Won, Jang-hyun style Daegeum Sanjo, comparative analysis was limited to two keys of c and f since they were consecutively played in Han, Ju-hwan style and Kim, Dong-jin style Daegeum Sanjo. The c primary key Gaemeon-gil melody had a total of 40 Jangdans of which 5 Jangdans (13%) were same and 5 Jangdans (13%) were similar, while f primary key Gaemeon-gil melody had a total of 14 Jangdans of which 2 Jangdans (14%) were same and 1 Jangdan (7%) was similar. When accumulated in Jinyangjo movement, c primary key Gaemeon-gil melody had 10 Jangdans (25%) out of a total of 40 Jangdans and f key Gaemeon-gil melody had 3 Jangdans (21%) out of a total of 14 Jangdans same or similar to Han, Ju-hwan style and Kim, Dong-jin style. Also, out of 54 Jangdans of the Gaemeon-gil melodies in two types of Jinyangjo movement, 13 Jangdans (24%) were same or similar to Han, Ju-hwan style and Kim, Dong-jin style. Therefore, it was found that the rest 41 Jangdans (76%) were creative melody of Won, Jang-hyun style. Moreover, b♭ primary key Gaemeon-gil appeared in 5 Jangdans only in Won, Jang-hyun style Daegeum Sanjo. ② In Jungmori movement, there were b♭ primary key Woojo-gil melody of 16 Jangdangs, and out of them, 1 Jangdan (6.3%) was same melody and 10 Jangdans (63%) were similar melodies to Han, Ju-hwan style and Kim, Dong-jin style Daegeum Sanjo melody. Therefore, only 5 Jangdans (32%) of Woojo-gil melody in Jungmori movement was creative melody. The c primary key Gaemeon-gil melody had a total of 29 Jangdans of which 1 Jangdan (3%) was same and 9 Jangdans (31%) were similar, while the rest 19 Jangdans (65%) were creative melody Won, Jang-hyun style. ③ In JungJungmori movement, there were b♭ primary Woojo-gil melody of 23 Jangdangs, and out of them, 6 Jangdans (26%) were same melody and 15 Jangdans (65%) were similar melodies. Therefore, only 4 Jangdans (9%) of Woojo-gil melody in Jungmori movement was creative Won, Jang-hyun style melody. Gyeongdeureum melody had a total of 9 Jangdans, and out of them, 1 Jangdan (33%) were same melody and 4 Jangdans (44%) were similar melodies. Only 4 Jangdans (9%) were creative Won, Jang-hyun style melody. Gaemeon-gil melody was played in three keys of c (24Jangdans), f (23 Jangdans), and g (3 Jangdan). Among them, c primary key Gaemeon-gil melody had 1 Jangdan (4%) same melody and 1 Jangdan(4%) similar melody to Han, Ju-hwan and Kim, Dong-jin style Daegeum Sanjo melody, and 22 Jangdans (92%) were creative Won, Jang-hyun style melody. The rest types of primary keys of f and g Gaemeon-gil melody were not same or similar to Han, Ju-hwan and Kim, Dong-jin style Daegeum Sanjo melody. When 3 types of keys Gaemeon-gil melodies in Jungjungmori movement are in Jungjungmori movement, only 2 Jangdans (4%) are same or similar and the rest 48 Jangdans (96%) were creative out of 50 Jangdans, and Won, Jang-hyun style melody was found to be creative. ④ Woojo-gil melody in Jajinmori movement has a total of 28 Jangdans composed of two primary keys, b♭ for 26 Jangdans and e♭ key for 2 Jangdans. The Woojo-gil melody were found to be the creative Won, Jang-hyun style melody which did not appear in Han, Ju-hwan and Kim, Dong-jin Daegeum Sanjo style. The Gaemeon-gil melody was played in two primary keys; c key Gaemeon-gil melody in a total of 100 Jangdans and 4 Jangdans (4%) were same melody and 20 Jangdans (20%) were similar melody. Therefore, 76 Jangdans (76%) were found to be the creative Won, Jang-hyun style melody. And f primary key Gaemeon-gil melody appeared in a total of 6 Jangdans which was not found in Han, Ju-hwan and Kim, Dong-jin style Daegeum Sanjo melody. Deolleongjae melody was played in a total of 20 Jangdans, which had no same or similar melody to Kim, Dong-jin style Daegeum Sanjo melody, except it had similarity in 11 Jangdans (55%) to Han, Ju-hwan Daegeum Sanjo. Won, Jang-hyun style was compared to Han, Ju-hwan and Kim, Dong-jin style Daegeum Sanjo melody to find same melody, similar melody, and its creative melody according to movements and the following are concise details of the study: Jinyangjo movement had a total of 80 Jangdans of which 34 J angdans (43%) were same or similar and 46Jangdans (57%) are the creative Won, Jang-hyun style melody. Jungmori movement has a total of 45 Jangdans of which 21 Jangdans (47%) were same or similar and 24 Jangdans (53%) were the creative Won, Jang-hyun style melody. Jungjungmori movement had a total of 82 Jangdans of which 32 Jangdans (39%) were same or similar and 50 Jangdans (61%) were the creative Won, Jang-hyun style melody. Jajinmori movement has a total of 152 Jangdans of which 35 Jangdans (23%) were same or similar and 117 Jangdans (77%) were the creative Won, Jang-hyun style melody. When it was comprehensively summarized over the total of 359 Jangdans, 118 Jangdans (23%) were same or similar to Han, Ju-hwan and Kim, Dong-Jin style Daegeum Sanjo, and 241 Jangdans (67%) were found the be the creative Won, Jang-hyun style Sanjo melody. Among them, two melodies of b♭ primary key Gaemeon-gil (5 Jangdans) in Jinyangjo and f primary key Gaemeon-gil (6 Jangdans) in Jajinmori were not observed in Han, Ju-hwan and Kim, Dong-Jin style Daegeum Sanjo. It was found Won, Jang-hyun overcame the melodies of teacher who had directly taught him or indirectly influenced him, changed melodies, completed melodies based on his rich musicality and diverse musical experiences, and established his school based on creative Daegeum Sanjo style. Daegeum Sanjo is classified by 「Sori Deoneum」 which was founded by Park, Jong-ki and was succeed by Han, Ju-hwan, Han, Beom-su, Seo, Yong-seok, Lee, Saeng-gang, and Won, Jang-hyun and 「Sinawi Deoneum」 which was founded by Kang, Baek-cheon and was succeed by Kim, Dong-jin, Kim, Dong-pyo, and Won, Jang-hyun. The study was carried out to find out same melody and similar melody between two prominent schools of Daegeum Sanjo, Won, Jang-hyun style and Han, Ju-hwan and Kim, Dong-jin style to define creative melody of to help formation of a new Daegeum Sanjo. I expect that the study becomes a guide in creating new Daegeum Sanjo with its future enhanced study of Sanjos of two Deoneum styles and find their creative characteristics through comparative analysis of two schools.

Enhanced nitrogen removal in A/O MBBR for treating nitrified anaerobic digestion effluent : effects of biocarrier and external carbon sources

Jang, Sojeong Sungkyunkwan University 2025 국내석사

Anaerobic digestion effluent (ADE), generated from biogas production processes, contains high concentrations of ammonia nitrogen and refractory organic matter. This wastewater can cause environmental issues like eutrophication if not properly treated. Even after primary nitrification, levels of nitrate and nitrite often persist, requiring external carbon supplementation for complete denitrification. Although methanol (MeOH) is commonly used as an external carbon source due to its high biodegradability and low cost, concerns regarding its flammability, toxicity, associated CO₂ emissions during production, and price volatility have highlighted the need for sustainable alternatives. Food waste condensate (FWC), a byproduct of food waste drying processes, has emerged as a promising alternative carbon source due to its abundance of biodegradable content, especially short-chain volatile fatty acids. The FWC used in this study exhibited strong acidity (pH 3.14), high organic content (tCOD =18,052  mg/L; acetic acid = 4,376 mg/L), and high carbon-to-nitrogen (C/N) ratio exceeding 400, suggesting significant potential for denitrification. However, most previous studies on denitrification performance have focused on wastewater with nitrate as the sole electron acceptor. Research investigating the performance of FWC under ADE conditions, in which both nitrate and nitrite coexist at elevated concentrations, remains limited. In this study, a lab-scale anoxic/oxic (A/O) moving bed biofilm reactor (MBBR) system was operated to comparatively evaluate the denitrification performance of MeOH and FWC as external carbon sources under nitrified ADE conditions. The MeOH-fed reactor achieved total ammonia nitrogen (TAN) and total nitrogen (TN) removal efficiencies of 97.4% and 90.2%, respectively, while the FWC-fed reactor exhibited comparable removal efficiencies of 92.0% TAN and 95.2% TN. In addition, the use of FWC eliminated the need for additional acid dosing required in MeOH-based systems, offering operational cost advantages. Moreover, bio-autopsy and morphological analyses of the biocarriers revealed that both reactors maintained stable biofilm structures and active microbial metabolism without excessive extracellular polymeric substance accumulation. Notably, the biocarriers from the FWC-fed reactor exhibited a more diverse denitrifying microbial community. 반류수(Anaerobic Digestion Effluent, ADE)는 바이오가스 생산 공정에서 발생하는 폐수로서 높은 농도의 암모니아성 질소와 난분해성 유기물을 포함하며, 적절히 처리되지 않을 경우 부영양화 등의 환경 문제를 일으킬 수 있다. 이러한 반류수는 일차적인 질산화 과정을 거친 후에도 상당량의 질산염과 아질산염이 잔류하기 때문에 완전한 탈질을 위해서는 외부 탄소원의 첨가가 필수적이다. 메탄올(MeOH)은 높은 생분해성과 저렴한 비용 덕분에 대표적으로 사용되는 외부 탄소원이지만, 인화성, 독성, 제조 과정에서 발생하는 CO₂배출 및 가격 변동성 등의 문제로 인해 지속 가능한 대체 탄소원에 대한 요구가 증가하고 있다. 최근 음식물류 폐기물 처리 과정에서 발생하는 건조응축수 (Food waste condensate, FWC)는 단쇄 휘발성 지방산과 같은 생분해성 화합물이 풍부하여 대체 외부 탄소원으로 주목받고 있다. 본 연구에서 사용한 FWC는 강산성 (pH 3.14)이며 매우 높은 유기물 함량(tCOD 약 18,052 mg/L; 아세트산 약 4,376 mg/L)을 지니고 있으며, C/N 비가 400 이상으로 나타나 외부탄소원으로서의 높은 가능성을 확인하였다. 그러나 기존 선행 연구는 주로 질산염을 유일한 전자수용체로 사용하는 조건에서 이루어졌으며, 질산염과 아질산염이 동시에 고농도로 존재하는 ADE 조건에서의 성능 평가 연구는 부족한 실정이다. 이에 본 연구에서는 질산화된 ADE 조건에서 MeOH와 FWC의 탈질 성능을 비교 평가하기 위해 실험실 규모의 A/O MBBR (Moving Bed Biofilm Reactor) 공정을 운영하였다. 그 결과, MeOH를 적용한 R1 반응조는 평균 97.4%의 암모니아 제거율 및 90.2%의 총질소 제거율을 달성하였으며, FWC를 적용한 R2 반응조 또한 92.0%의 암모니아 제거율 및 95.2%의 총질소 제거율을 나타내어 유사한 수준의 처리 효율을 유지하였다. 또한, FWC는 자체의 낮은 pH로 인해 MeOH 사용 시 필요했던 별도의 산 투입이 불필요하여 운영 비용 면에서도 이점이 존재함을 확인하였다. 추가적으로, 담체의 형태학적 분석 및 미생물 군집 분석등의 결과를 통해 두 반응조 모두 과도한 세포외고분자물질 (EPS) 축적 없이 안정적인 생물막 구조와 활발한 미생물 대사를 유지하였으며, 특히 FWC 공급 반응조의 담체에서 보다 다양하고 풍부한 탈질 미생물 군집이 확인되었다. 이러한 결과를 바탕으로, FWC는 MeOH를 대체할 수 있는 지속 가능하고 경제적이며 탄소중립적인 외부 탄소원으로 활용 가능성이 있음을 시사한다.

Study of Optical Properties of Si and Ge based nanostructures : Growth, Characterization and First-principle calculations

Jang,Seunghun The Graduate School of the University of Seoul 2013 국내박사

(A) study on the evaluation of the developed robot vision control schemes in real time for the estimation of the fixed target

장민우 Chosun University 2017 국내석사

The study of E-nose based on metal oxide semiconductor

Hyun Woo Jang DGIST 2020 국내석사

Electronic nose (E-nose) is an artificial olfactory system which imitating olfactory system of living or-ganisms like human or insects, has been gradually studied due to its large potentiality on various areas like food industry or diagnosis of disease. Especially, E-nose based on metal oxide semiconductor is widely stud-ied due to its advantages like easy fabrication, low cost and high sensitivity on many harmful, environmen-tal, explosive and toxic gases. However, still they have some limitations like high working temperature due to their activation energy barrier. To achieve high sensitivity and resolution, working temperature above 200℃ was usually required in many studies. Therefore, enhancing sensitivity in room temperature is one of the chal-lenges for metal oxide semiconductor-based E-nose. In the present study, highly sensitive E-nose under room temperature were designed using IGZO and ZnO. Thin film transistor system was chosen as a base design of E-nose. IGZO and ZnO layer has deposited by sputter and annealed under 300℃ for 1 hour. Gas response of E-nose was measured by shift of transfer curve and two terminal real time resistance measurement. IPA gas was applied on device by N2 gas which has low chemical reactivity. IGZO shows significantly high gas response compares to ZnO due to its difference in physical-chemical structures. And due to their amorphous state, both IGZO and ZnO TFT show poor recov-ery characteristics under room temperature. They showed significantly enhanced recovery characteristic un-der 90℃ which is not appropriate for most of organic materials. To solve the problems, ZnO nanowire junction-based E-nose was prepared by hydro-thermal synthesiz-ing process. ZnCl and HMTA was used as solution for synthesizing. Solution changing period and synthesiz-ing time was controlled to fabricate various structure of nanowires. They show better gas response than ZnO TFT due to its significantly increased surface to volume ratio. Additionally, they show highly enhanced re-covery characteristic due to their crystal structure. As density of nanowires increase, recovery characteristic of nanowires was weakened. As length of nanowires increases, number of junctions increased, and it leads to enhancement in gas sensitivity. ZnO nanowires shows high sensitivity on Isopropyl alcohol and DI water. Al-so, they show excellent sensitivity on ethyl butyrate, eugenol and decanal which are odorants smells like fruity, clove and orange. E-nose based on ZnO nanowire junction has many advantages such like eco-friendly, bio-compatibility, low working temperature, high sensitivity on various gas and smells, and en-hanced recovery characteristic. Therefore, this E-nose device can be applied to various field such as bio-material enhanced E-nose, wearable E-nose or in implantable type of E-nose. 전자 코 기술은 사람이나 곤충과 같은 살아있는 유기체의 후각 기관을 모방하는 기술로 식품 산업과 같은 다양한 분야에 널리 이용될 수 있는 잠재력을 가지고 있다. 특히, 금속 산화물을 기반으로 하는 전자 코의 경우 높은 민감도와 더불어 제작이 용이하고 저렴하며 대부분의 위험한 독성이나 인화성을 가지는 기체들이 측정 가능하다는 장점으로 인해 널리 연구되고 있다. 하지만 여전히 많은 연구에서 금속 산화물 반도체의 높은 활성화 에너지 장벽에 의해 좋은 반응성을 얻기 위해서는200℃가 넘는 작동온도가 필요하다는 단점을 보여주고 있다. 따라서 본 연구에서는 금속 산화물 반도체중 하나인 IGZO와 산화 아연 나노 와이어를 이용하여 상온에서도 높은 민감도를 가지는 전자 코에 대해 연구하였다. IGZO와 산화 아연을 사용하여 박막 트랜지스터를 스퍼터를 활용하여 제작하였고, 전류 소비를 줄이기 위해 300℃에서 1시간 어닐링하였다. 특성곡선의 움직임과 채널 물질의 화학적 반응에 의한 채널 저항의 실시간 변화를 통해 가스를 측정하였다. 이소프로필알콜을 낮은 화학 반응성을 가진 질소 가스를 이용해 전달하였다. 두 종류의 박막 트랜지스터의 가스 반응을 비교하였을 때, IGZO를 이용한 박막 트랜지스터가 채널 물질의 물리 화학적 구조 차이에 의해 더욱 큰 반응성을 나타냈다. 측정 후 복원에 있어서는 IGZO 와 산화 아연 모두 제작 방식에 의한 비결정성 구조에 의해 상온에서는 복원이 되지 않았고 90℃의 온도에서 30분 이상 가열하였을 때 완전히 복원되는 특성을 보였다. 따라서 이는 체내 삽입형이나 생체 분자를 이용한 센서에는 적합하지 않음을 확인했다. 산화 아연 나노 와이어 접합을 이용한 전자 코는 수열합성을 통해 제작되었다. 합성을 위한 수용액을 갈아주는 주기와 전체 합성 시간을 조절하여 다양한 구조의 나노 와이어를 제작하였고 전체적인 부피-면적 비율의 증가로 반응성이 증가하는 것을 확인하였다. 나노 와이어의 밀집도와 전자 코의 측정 후 복원 특성이 반비례 관계에 있음을 확인하였으며 나노 와이어 길이의 증가로 인한 접합 부위의 증가가 전자 코의 반응성에 선형적인 영향을 미침을 확인하였다. 또한, 증류수, 이소프로필알콜 등의 다양한 가스와 과일 향, 정향, 오렌지향 등의 다양한 향을 산화 아연 나노 와이어 접합을 이용한 전자 코로 측정할 수 있음을 확인하였다. 이러한 산화 아연 나노 와이어 접합을 이용한 전자 코의 경우 확인된 반응성과 복원에 대한 장점 외에도 생체 적합성, 환경 친화적이라는 장점이 있어 추후에 생체분자를 이용한 전자코나 체내 삽입형 전자 코 등에 다양하게 활용될 수 있다.

(A) comparative study on the startup discourse between United States and China with a structural topic model

Jang, Jaeyeon Sungkyunkwan university 2021 국내석사

This essay explores significant cultural differences on startup discourses between United States and China by demonstrating a big data analysis through Structural Topic Modeling. Results and findings were interpreted with Hofstede’s cultural dimensions, indicating that the conventional theory of social science was applicable when it comes to explaining technological subjects. The data used in this essay are online news data covering 2000 to 2019 from LexisNexis, for projecting which articulates a regional distinctiveness of environmental trends that foster startups. According to the results, United States and China a have significant difference in major discourses. United States which a higher individuality score, tends to be linked to the topics about Politics and Gender issues. Meanwhile China with less individuality score but higher long term orientation score, pays attention to the Governmental policy and Entrepreneurship. 이 에세이는 Structural Topic Modeling을 활용한 빅데이터 분석을 통해 미국과 중국 사이의 창업 담론에 대한 중요한 문화적 차이를 탐색한다. 연구 결과는 Hofstede의 문화적 차원으로 해석되었고, 이는 기존의 사회과학 이론이 기술적 주제를 설명할 때 적용 가능하다는 것을 보여준다. 본 에세이에는 스타트업을 육성하는 환경 트렌드의 지역적 특수성을 알아보기 위하여 LexisNexis의 2000년부터 2019년까지 온라인 뉴스 데이터를 분석하였다. 그 결과에 따르면 미국과 중국은 주요 담화에서 상당한 차이를 보인다. 개인주의 성향이 높은 미국은 주요 담화들이 정치와 성별 문제에 관한 주제와 연계되어 있는 경향이 있다. 반면 집단주의, 장기지향적 성격을 보이는 중국은 국가정책과 기업가정신에 주목한다.

Lattice paths on flow polytopes, grothendieck polynomials, and orthogonal polynomials

Jang, Jihyeug Sungkyunkwan University 2024 국내박사

Lattice paths are widely used in combinatorics. They provide combinatorial interpretations for some integer sequences, and even for polynomials. In this thesis, we explore how lattice paths emerge in various processes and how they are independently used in the fields of flow polytopes, Grothendieck polynomials, and orthogonal polynomials. More precisely, in joint work with J.S. Kim, we introduce definitions for labeled Dyck paths and doubly labeled Dyck paths, and use them to compute the volumes of particular flow polytopes. In joint work with B.-H. Hwang, J.S. Kim, M. Song, and U.-K. Song, we use non-intersecting lattice paths in the process of expanding refined canonical stable Grothendieck polynomials and their duals into Schur functions. From these, we express the Schur coefficients as weighted sums of specific tableaux, called elegant tableaux and inelegant tableaux. Lastly, in joint work with D. Kim, J.S. Kim, M. Song, and U.-K. Song, we introduce peak-valley sequences to provide combinatorial interpretations for the negative moments of classical orthogonal polynomials. 본 학위 논문에서는 격자 경로의 다양한 활용과 조합적 해석을 탐구한다. 격자 경로는 조합론에서 핵심 도구로 쓰이는데, 여기서는 특히 유동 다면체, 그로센딕 다항식, 직교 다항식 분야에서 격자 경로의 활용을 살펴본다. 구체적으로, 레이블이 지정된 딕 경로와 이중 레이블이 지정된 딕 경로의 정의를 도입하고, 이를 활용하여 특정 유동 다면체의 부피를 계산하였다. 또한, 교차하지 않는 격자 경로들을 사용하여 세분화된 그로센딕 다항식을 슈어 함수로 전개했을 때의 계수를 설명해주는 타블로 모델을 제시하였다. 마지막으로, 피크-벨리 수열을 도입하고 직교 다항식의 음의 모멘트를 조합적으로 해석하는 방법을 소개하였다.

Analysis on the Characteristics of Direct-Coupled Permanent Magnet Wind Turbine Generator woth Single-Phase Full-Bridge Inverter

최장영 忠南大學校 大學院 2009 국내박사

Random liquid crystal pattern-based optical physical unclonable function development and analysis

Jang, Seongmin Sungkyunkwan University 2023 국내석사

Physical Unclonable Function(PUF)은 보안의 중요성이 증대되면서 주목받고 있는 하드웨어 기반 보안 기술이다. 다양한 분야의 재료 및 기술들이 PUF에 응용되고 있는데 산업에 적용되기에는 안정성 및 복잡한 기술 등 한계가 존재한다. 이에 따라 쉽게 제작 및 구현이 가능하고 화학적인 안정성이 우수한 PUF 기술에 대한 연구가 지속되어야 한다. 액정 관련 연구는 주로 일정한 방향으로 배열하거나 주기적인 패턴을 형성하는 연구가 진행되어왔다. 본 논문에서는 공정 과정에서 통제불가능한 변수를 이용하여 랜덤한 액정 패턴을 유도하고 이를 이용한 광학적 PUF를 제안한다. 본 논문에서는 액정 기반 랜덤한 패턴의 형성 메카니즘과 시뮬레이션 분석에 대해 기술하고, 해당 기술을 이용하여 이론적으로 최대 12ⁿ개의 조합이 가능한 optical PUF를 기술한다. 액정 패턴은 마이크로 구조 배열을 갖는 Noa65 기판을 제작하여 액정 셀에 도입하고 액정 물질을 코팅하여 제조한다. 본 논문에서 사용된 액정 혼합물은 RM 물질과 용매의 혼합물이며, 용매 증발에 따라 isotropic phase에서 nematic phase로 상전이가 일어난다. 상전이 시, 초기 액정 분자의 배열은 자연적으로 발생하는 요소로 공정 과정에서 통제 불가능한 요소이다. 랜덤한 액정 패턴 형성 메커니즘 분석을 위해, TechWiz LCD 3D 소프트웨어를 이용하여 액정의 국부적인 초기 배열에 따라 액정 분자의 거동이 달라지고 이에 따라 액정 패턴의 종류가 결정됨을 확인했다. 각 패턴들의 대해 시간에 따른 탄성 에너지 밀도를 비교한 결과, 각 패턴은 서로 다른 에너지로 평형을 이루고 있다. 즉, 형성된 모든 패턴은 서로 다른 에너지에서 안정한 상태이고 이는 이 시스템이 metastable임을 의미한다. 또한, 구조물 사이의 간격이 커질수록 생성되는 각 액정 패턴의 평형 탄성 에너지가 감소하는 경향을 보이고 특정 간격에서 패턴들의 평형 에너지의 대소관계가 바뀐다. 이러한 현상에 의해 구조물 사이의 간격에 따라 형성 가능한 액정 패턴 종류가 결정된다. Physical unclonable function (PUF) is a hardware-based security technology that has attracted attention as the significance of security increases. Materials and technologies in various fields are applied to PUF; however, limitations exist, such as stability and complex technology for industrial applications. Accordingly, studies on the PUF technology, which can be easily fabricated and implemented as well as has excellent chemical stability, must be conducted. Studies related to liquid crystals have mainly been conducted by arranging them in a particular direction or forming periodic patterns. In this study, a random liquid crystal pattern is induced using uncontrollable variables and an optical PUF using this pattern is proposed. This study examines the formation mechanism and simulation analysis of random liquid crystal optical patterns and an optical PUF that can combine up to 12ⁿ patterns using the corresponding technology. Liquid crystal patterns are manufactured by preparing a Norland optical adhesive 65 substrate with a microstructure array, introducing it into a liquid crystal cell, and coating the liquid crystal material. The liquid crystal mixture used in this study was a mixture of RM material and a solvent, and an isotropic-to-nematic phase transition occurred because of solvent evaporation. Currently, the arrangement of the initial liquid crystal molecules during phase transition occurs naturally and uncontrollably. Using the TechWiz LCD 3D software, the behavior of liquid crystal molecules changed according to the local initial arrangement of liquid crystals and the resulting liquid crystal patterns were determined. Based on a comparison of the elastic energy density over time for each pattern, each pattern is in equilibrium with different energies. That is, all the patterns formed are stable at different energies, meaning the system is metastable. In addition, as the distance between the structures increases, the equilibrium elastic energy of each generated liquid crystal pattern decreases as well, and the magnitude relationship of the equilibrium energy of the patterns changes at a particular distance. Therefore, the types of liquid crystal patterns that can be formed are determined by the spacing between the structures.

DEVELOPMENT OF A GROWTH-BASED VIRUS AEROSOL CONCENTRATOR FOR RAPID DETECTION OF BIOAEROSOLS

Junbeom Jang Ulsan National Institute of Science and Technology 2024 국내박사