Micro via and line patterning for PCB using imprint technique

Seunghyun Ra,Choonkeun Lee,Jaechoon Cho,Sangmoon Lee,Jungwoo Lee,Myungho Hong,Jungbok Kwak 한국물리학회 2008 Current Applied Physics Vol.8 No.6

Today’s electronic devices such as mobile phones, PDA, computers, etc. have more functions in a smaller size. Thus conducting lines and via holes of PCB (printed circuit board) which has a role of land for all kinds of electronic components are getting finer. In this study, the conducting lines and via holes are produced using thermal imprint technique rather than the conventional photo-lithography process. Imprint technique is a press process that transfers patterns of stamp to resins. Imprint technique is used to produce micro size trench lines and via holes in epoxy resins. Resins used in this work are silica (SiO₂) reinforced epoxy. Resins were imprinted using 10 * 10 mm size Ni or polymer stamp. Line/ space of pattern is 10/10 lm while diameter of via hole is 30 lm. The depths of lines and via holes are 15 and 30 lm, respectively. The anti-sticking treated stamp and epoxy resins were pressed at 100℃ for 30 min in vacuum. The stamp was released after resins were cured for 1 h at 130℃. All patterns of stamp were successfully transferred with high fidelity and any noticeable defect was not observed within imprinted area. Imprinted resins were de-smeared to remove the residue at the bottom of via holes and to enhance the adhesion of resins with Cu. Electro/less copper plating was followed to fill in the imprinted patterns. Since the excess Cu layer was formed on the resins during Cu plating, the planarization process was introduced to obtain isolated lines and via holes. Today’s electronic devices such as mobile phones, PDA, computers, etc. have more functions in a smaller size. Thus conducting lines and via holes of PCB (printed circuit board) which has a role of land for all kinds of electronic components are getting finer. In this study, the conducting lines and via holes are produced using thermal imprint technique rather than the conventional photo-lithography process. Imprint technique is a press process that transfers patterns of stamp to resins. Imprint technique is used to produce micro size trench lines and via holes in epoxy resins. Resins used in this work are silica (SiO₂) reinforced epoxy. Resins were imprinted using 10 * 10 mm size Ni or polymer stamp. Line/ space of pattern is 10/10 lm while diameter of via hole is 30 lm. The depths of lines and via holes are 15 and 30 lm, respectively. The anti-sticking treated stamp and epoxy resins were pressed at 100℃ for 30 min in vacuum. The stamp was released after resins were cured for 1 h at 130℃. All patterns of stamp were successfully transferred with high fidelity and any noticeable defect was not observed within imprinted area. Imprinted resins were de-smeared to remove the residue at the bottom of via holes and to enhance the adhesion of resins with Cu. Electro/less copper plating was followed to fill in the imprinted patterns. Since the excess Cu layer was formed on the resins during Cu plating, the planarization process was introduced to obtain isolated lines and via holes.

Complete genome sequencing of <i>Shigella</i> sp. PAMC 28760: Identification of CAZyme genes and analysis of their potential role in glycogen metabolism for cold survival adaptation

Han, So-Ra,Kim, Do Wan,Kim, Byeollee,Chi, Young Min,Kang, Seunghyun,Park, Hyun,Jung, Sang-Hee,Lee, Jun Hyuck,Oh, Tae-Jin Elsevier 2019 Microbial pathogenesis Vol.137 No.-

<P><B>Abstract</B></P> <P> <I>Shigella</I> sp. PAMC 28760 (isolated from <I>Himantormia</I> sp. lichen in Antarctica) is a gram-negative, non-sporulating bacterium that has cellulolytic and amylolytic characteristics as well as glycogen metabolic pathways. In this study, we isolated <I>S.</I> sp. PAMC 28760 from Antarctic lichen, and present the complete genome sequence with annotations describing its unique features. The genome sequence has 58.85% GC content, 4,278 coding DNA sequences, 85 tRNAs, and 22 rRNA operons. 16S rRNA gene sequence analyses revealed strain PAMC 28760 as a potentially new species of genus <I>Shigella</I>, showing various differences from pathogenic bacteria reported previously. dbCAN2 analyses revealed 91 genes related to carbohydrate-metabolizing enzymes. <I>S.</I> sp. PAMC 28760 likely degrades polysaccharide starch to obtain glucose for energy conservation. This study provides a foundation for understanding <I>Shigella</I> survival adaptation mechanisms under extremely cold Antarctic conditions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Shigella</I> sp. PAMC 28760 from an Antarctic lichen has cellulolytic, amylolytic, and glycogen metabolic pathway. </LI> <LI> The complete genome of <I>Shigella</I> sp. PAMC 28760 showing differences from pathogenic reported previously. </LI> <LI> The foundation for understanding <I>Shigella</I> adaptation mechanism to extremely conditions is provided. </LI> </UL> </P>

집합적 효능의 대안적 측정 연구 : 공동주택 경비원을 대상으로

정재훈(Jaehoon Jung),라광현(Kwanghyun Ra),이승현(Seunghyun Lee),박희균(Heekyun Park) 한국셉테드학회 2020 한국셉테드학회지 Vol.11 No.2

도시개발 사업의 성과 측정을 위해서 물리적인 지표와 더불어 사회적인 지표의 개발 및 측정이 요구되고 있다. 이 연구는 기존의 지역 자생력 및 삶의 질에 대한 평가 도구를 검토하고 국내 거주 특성을 반영하여, 지역 자생력 및 삶의 질 평가를 위한 새로운 조사 방법을 개발하였다. 지역사회의 통합 및 자생력을 평가하는 대표적 척도인 집합적 효능(collective efficacy)을 효율적으로 측정하기 위해 도시의 종합적 기능회복을 위한 도시재생과 복합용도개발을 도시개발의 기조로 삼고 있는 세종특별자치시(행복도시)를 연구 지역으로 선정하였다. 조사의 효율성을 높이기 위해 해당 공동주택 주민과 상시로 접촉하는 경비원을 대상으로 설문을 하였다. 주요 조사 대상으로 행복도시에 최초로 입주한 A생활권 7개 아파트 단지에 근무하는 경비원 36명을 실험집단으로, 조사 시점 기준 가장 최근에 입주한 B생활권 6개 아파트 단지에 근무하는 경비원 25명을 비교집단으로 선정하였다. 조사는 2018년 2월 27일부터 3월 1일까지 3일간 자기기입식 설문조사를 진행하여 집합적 효능의 하위변인인 해당 아파트 단지의 비공식적 사회통제, 지역사회 응집력, 지역사회 안전, 지역사회 자원 등 주민들의 생활에 대한 전반적인 실태에 대해 파악하였다. 조사 결과 연구지역 및 비교지역 간 안전 인프라 및 인식에는 큰 차이가 없지만, 지역 자생력 및 삶의 질에는 다소 간의 차이가 있으며, 입주기간이 길었던 연구지역에서 비교적 높은 지역 자생력과 삶의 질을 나타냈다. 이 연구는 국내 실정에 맞는 도시 자생력 및 삶의 질을 측정하는 효율적인 방식을 모색했다는 점에서 가치가 있지만, 조사 결과를 일반화함에 있어 한계를 지닌다. Recently, in urban development projects, we want to improve the lives of residents in the community through physical development such as Mixed-use Development, but it has not actually led to an improvement in the quality of life. In this regard, as the development and measurement of social indicators as well as physical indicators are required to measure the performance of urban development projects, this study examines existing regional self-sufficiency and quality of life assessment tools and reflects domestic residential characteristics. In addition, a new research method was developed to assess regional self-sufficiency and quality of life. Sejong-si, which uses urban regeneration and Mixed-use Development as the basis for urban development to comprehensively restore the city s function to effectively measure collective efficacy, a representative measure of community integration and self-sufficiency. Sejong-si was selected as the study area. To increase the efficiency of the survey, a questionnaire was surveyed for security guards who are in constant contact with residents of the apartment complex. As a main survey, 36 guards working in seven apartment complexes in A living zone, the first to move into Sejong-si, were selected as experimental groups, and 25 guards working in six apartment complexes in B living area were selected as comparative groups based on the basis of the survey. The survey was conducted for three days from February 27 to March 1, 2018 to conduct a self-written questionnaire survey of security guards working at the complex to understand the overall status of residents lives, including informal social control, community cohesion, community safety, and community resources of the apartment complex, which is a sub-variable of collective efficacy. As a result of the survey, there was no significant difference in safety infrastructure and perception between the experimental groups and the comparative groups, but there were some differences in the local self-sufficiency and quality of life, and the relatively high local self-sufficiency and quality of life in the research area where the tenancy was long. The study is valuable in that it sought an efficient way of measuring urban self-sufficiency and quality of life suitable for domestic circumstances, but has limitations in generalizing the survey results.

복합화력 배열회수보일러 고압증기 온도제어루프 최적 튜닝

윤수용(SooYong Yun),최인규(InKyu Choi),라우현(WooHyun Ra),변승현(SeungHyun Byun),우주희(JooHee Woo),신만수(ManSu Shin),임진곤(JinGon Lim) 대한전기학회 2021 대한전기학회 학술대회 논문집 Vol.2021 No.7

생체 외 및 생체 내 실험조건에서 나노화 벌 화분의 안전성 규명

편해인(Hae-In Pyeon),소수정(Soojeong So),박지아(Jia Bak),이승현(Seunghyun Lee),이승민(Seungmin Lee),서화진(Hwa-Jin Suh),임제오(Je-Oh Lim),김정우(Jung-Woo Kim),김선연(Sun Youn Kim),이세라(Se Ra Lee),이용현(Yong Hyun Lee),정일경(Il Kyung 한국생명과학회 2018 생명과학회지 Vol.28 No.5

벌 화분은 영양보조제와 전통의약품으로 오랫동안 사용되어 왔다. 그러나 벌 화분은 두터운 외피를 갖고 있어 산이나 알칼리는 물론 위장관의 소화효소와 기계적 압력에 의해서도 잘 파괴되지 않는 단점이 있다. 이로 인해, 벌 화분을 경구로 섭취할 때 생체이용률은 10-15%에 불과한 실정이다. 이러한 문제점을 극복하기 위해 본 연구진은 이전의 연구에서 습식나노분쇄 기술을 소개하였고 이를 통해 활성성분의 추출률이 약 11배 증가함을 보고하였다. 본 연구에서는 습식나노분쇄를 통해 제조한 나노화 벌 화분의 안전성을 증명하고자 하였다. 먼저, 흰쥐와 비글견에서 단회 투여 독성 시험을 진행하였다. 나노화 벌 화분의 투여 용량은 흰쥐는 5, 10 또는 20 g/kg, 비글견은 1.5, 3 또는 6 g/kg으로 설정하였다. 흰쥐에서는, 10 g/kg 또는 그 이상의 용량을 투여한 동물에서 색변이 관찰되었다. 비글견에서는 6 g/kg 투여군에서 나노화 벌 화분 투여 4시간 후에 설사가 관찰되었다. 그러나, 흰쥐와 비글견 모두에서 뚜렷한 임상증상이 관찰되지 않았으며 안락사 후 부검을 진행한 결과에서도 장기의 이상이 관찰되지 않았다. 다음으로 나노화 벌화분의 유전독성을 복귀돌연변이시험, 염색체이상시험 및 소핵시험을 이용하여 확인하였다. 소핵시험에서는 시험에 사용한 최대용량인 2,000 mg/kg에서도 독성이 발견되지 않았다. 마찬가지로 복귀돌연변이시험과 염색체이상시험에서는 실험에 사용된 최고 농도에서도 독성을 나타내지 않았다. 종합하면 나노화 벌 화분은 본 실험에서 설정한 최고 용량인 20 g/kg/day의 용량까지는 매우 안전한 것으로 판단되며 이러한 결과는 나노화 벌 화분을 기능성 식품 또는 천연물 의약품으로 개발하는 데 중요하게 이용될 것으로 기대된다. Bee pollen has an outer wall which is resistant to both acidic and basic solutions and even the digestive enzymes in the gastrointestinal tract. Therefore, the oral bioavailability of bee pollen is only 10-15%. A previous study reported on wet-grinding technology which increased the extraction of active ingredients from bee pollen by 11 times. This study was designed to investigate the safety of wetground bee pollen. First, a single dose of wet-ground bee pollen was tested in both rats and beagle dogs at dosages of 5, 10, and 20 g/kg and 1.5, 3, and 6 g/kg, respectively. In rats, compound-colored stools were found in those administered 10 g/kg or more of wet-ground bee pollen. In beagle dogs, 6 g/kg of wet-ground bee pollen induced diarrhea in one male for four hours. However, no obvious clinical signs were found through the end of the experiment in rats and beagle dogs. In addition, no histological abnormality was found in all animals. The data indicates that a single dose of up to 20 g/kg of wet-ground bee pollen is safe. Next, the genetic toxicity of nano-sized bee pollen was tested. This study employed a bacterial reverse mutation test, a micronucleus assay, and a chromosomal aberration assay. In the micronucleus assay, there was no genetic toxicity up to the dosage of 2 g/kg. There was also no genetic toxicity in the bacterial reverse mutation test and chromosomal aberration assay. This data provides important information in developing nano-sized bee pollen into more advanced functional foods and herbal medicines.

vSlide: 동영상 강좌의 슬라이드 화질 개선을 위한 실용적인 방안

박성수(Sungsoo Park),김종윤(Jongyoon Kim),박준명(Junmyeong Park),장승선(Seunghyun Jang),라지현(Jihyun Ra),이진우(Jinwoo Lee),김준호(Junho Kim) 한국컴퓨터그래픽스학회 2014 한국컴퓨터그래픽스학회 학술대회 Vol.2014 No.7