잉크젯 프린팅 방식으로 형성된 구리 배선의 전기적 특성 평가

김광석,구자명,정재우,김병성,정승부,Kim, Kwang-Seok,Koo, Ja-Myeong,Joung, Jae-Woo,Kim, Byung-Sung,Jung, Seung-Boo 한국마이크로전자및패키징학회 2010 마이크로전자 및 패키징학회지 Vol.17 No.3

직접인쇄기술 방식은 기존의 포토리소그래피 방법을 이용한 패터닝 기술에 비해 저비용, 간단한 공정 과정, 친환경성 등 여러 장점들로 인해 미세 회로 형성 분야의 그린 테크놀로지로 최근 각광받고 있다. 이러한 프린팅 기반의 전자기술을 상용화하기 위해서는 프린팅 방식으로 형성된 회로의 전기적 특성 평가가 필수적인데, 이에 본 연구에서는 구리 잉크를 이용하여 잉크젯 프린팅 방식으로 2 가지 타입, parallel transmission line(PTL)과 coplanar waveguide(CPW) 구조의 회로를 형성하고 $250^{\circ}C$에서 30분 동안 소결하여 완성하였다. 전류-전압 그래프로 직류 저항을 측정하여 벌크 구리의 비저항 값의 약 3.3배되는 평균 0.558 ${\mu}{\Omega}{\cdot}cm$의 비저항 값을 도출하였고 회로의 고주파 특성 평가를 위해 주파수 범위 0~30 GHz에서 probe station chuck과 샘플 간의 갭 유무에 따른 scattering parameter를 측정하였다. 모든 시편에서 5 dB 이하의 반사 특성을 보였으며, PTL 회로가 CPW 구조보다 전반적으로 더 좋은 통과 특성을 나타내었다. Direct printing technology is an attractive metallization method, which has become immerging as "Green technology" to the conventional photolithography, on account of low cost, simple process and environment-friendliness. In order to commercialize the printed electronics in industry, it is essential to evaluate the electrical properties of conductive circuits using direct printing technology. In this contribution, we focused on the electrical characteristics of inkjet-printed circuits. A Cu nanoink was inkjet-printed onto a Bisaleimide triazine(BT) substrate with parallel transmission line(PTL) and coplanar waveguide(CPW) type, then was sintered at $250^{\circ}C$ for 30 min. We calculated the resistivity of printed circuits through direct current resistance by the measurement of I-V curve: the resistivity was approximately 0.558 ${\mu}{\Omega}{\cdot}cm$ which is about 3.3 times that of bulk Cu. Cascade's probe system in the frequency range from 0 to 30 GHz were employed to measure the Scattering parameter(S-parameter) with or without a gap between the substrate and the probe station chuck. The result of measured S-parameter showed that all printed circuits had over 5 dB of return loss in the entire frequency range. In the curve of insertion loss, $S_{21}$, showed that the PTL type circuits had better transmission of radio frequency (RF) than CPW type.

성인의 자연발생 초기 치주염시 치은조직의 전자현미경적 연구

김광석,최성근,김종관,Kim, Kwang-Seok,Choi, Sung-Keun,Kim, Chong-Kwan 대한치주과학회 1983 Journal of Periodontal & Implant Science Vol.13 No.1

외국학술지지원센터 운영 사업의 비용편익분석

김광석,오동근,여지숙,Kim, Kwang-Seok,Oh, Dong-Geun,Yeo, Ji-Suk 한국도서관정보학회 2012 한국도서관정보학회지 Vol.43 No.1

이 연구는 2011년 현재 운영중인 7개 외국학술지지원센터의 운영효과를 점검하기 위해 그 비용과 편익을 분석하였다. 사업개시부터 30년 경과시점을 기준으로 한 투자타당성 분석 결과, 비용편익 비율(BCR)은 0.99, 내부수익률(IRR)은 5.49%, 누적순현재가치(NPV)는 -507백만원으로 나타났다. 다만 민감도분석에서는 저널 이용건수와 사회적 할인율, 중복구독 중단 등의 항목의 변화에 따라 비용편익비율이 변화할 수 있음을 제시하였다. This article analyzes the costs and benefits of the seven individuals centers of Foreign Research Information Center. Results of the investment feasibility analysis based on 30 years time span show that 0.99 of BCR (Benefit-Cost Ratio), 5.49% of IRR (Internal Rate of Return), and -507 million Won of NPV (Net Present Value). Sensibility analysis suggests that BCR can be influenced by the journal usage, social rate of discount, and elimination of the duplicate journal among individual centers.

구치부(臼齒部) 도재전장주조관(陶在前裝鑄造冠) 변연형태(邊緣形態)에 따른 응력분석(應力分析)

김광석,송광엽,박찬운,Kim, Kwang-Seok,Song, Kwang-Yup,Park, Charn-Woon 대한치과보철학회 1987 대한치과보철학회지 Vol.25 No.1

To study the mechanical behaviors of the margins of porcelain-fused-to-metal crown on the posterior teeth, 5 types of margins on the lower first molar were chosen, and then the finite element models were constructed. 50kg forces were applied to the porcelain on the axial wall supported by the metal vertically. The displacements and stresses of the porcelain-fused-to-metal crown were analyzed to investigate the influence of the type of margins. The results were as follows; 1. High tensile stresses were exhibited on the porcelain of the portion of the coronal line angle insufficient metallic support. 2. In case metal coping had a good supporting form to vertical force, uniform compressive stresses were exhibited on their supporting form. 3. Tensile stresses in the inframetallic margin on the series of the shoulder with a bevel margins were decreased in the bevel portion. 4. Principal stresses on the metal of the chamfer marginal portion were decreased comparing with the series of the shoulder margins. 5. The noticeable compressive stress gradients were exhibited between axial cement layer and metal on the series of the shoulder margins. 6. The principal stresses on the marginal cement layer were higher than that of the occlusal surface and axial wall.

파워디바이스 패키징의 열제어 기술과 연구 동향

김광석,최돈현,정승부,Kim, Kwang-Seok,Choi, Don-Hyun,Jung, Seung-Boo 한국마이크로전자및패키징학회 2014 마이크로전자 및 패키징학회지 Vol.21 No.2

Technology for high power devices has made impressive progress in increasing the current density of power semiconductor, system module, and design optimization, which realize high power systems with heterogeneous functional integration. Depending on the performance development of high power semiconductor, packaging technology of high power device is urgently required for efficiency improvement of the device. Power device packaging must provide superior thermal management due to high operating temperature of power modules. Here we, therefore, review critical challenges of typical power electronics packaging today including core assembly processes, component materials, and reliability evaluation regulations.

사물인터넷 시대의 생체인식 스마트 센서 기술과 연구 동향

김광석,김대업,Kim, Kwang-Seok,Kim, Dae Up 한국마이크로전자및패키징학회 2016 마이크로전자 및 패키징학회지 Vol.23 No.2

With the pace of rapid innovation in technology of IoT (Internet of Things) and smart devices, biometric technology becomes one of the most progressive industries. Recent trends in biometrics show most are focused on embedding biometric sensors in mobile devices for user authentication. Multifactor biometrics such as fingerprint, retina, voice, etc. are considering as identification system to provide users with services more secured and convenient. Here we, therefore, demonstrate some major technologies and market trends of mobile biometric technology with its concerns and issues.

시스템 사고에 의한 방위력개선비 결정요인 분석 및 정책 레버리지 전략 연구

김광석 ( Kim Kwang-seok ),심상렬 ( Shim Sang-ryul ) 국방대학교 안보문제연구소 2019 국방연구 Vol.62 No.3

본 연구는 방위력개선비 결정 시스템의 구조적인 문제점을 파악하고 정책 레버리지 전략을 도출함으로써 방위력개선비를 결정하는 정책결정자들에게 합리적인 판단의 논거를 제시하고자 하는 데 목적을 두고 있다. 이를 위해 먼저 국방비 결정이론과 선행연구를 바탕으로 전력증강에 직접적으로 영향을 미치는 방위력개선비의 주요 결정요인 6개를 선정하였다. 이것은 한미동맹관계, 정책의지, 의사결정 시스템, 국가경제능력, 북한의 위협, 주변국의 위협이다. 또한, 시스템 사고를 이용하여 선정된 6개 결정요인들의 인과지도를 작성하고, 인과관계를 분석하였다. 그리고 이러한 분석 결과를 바탕으로 정책 레버리지를 도출하였다. 방위비분담금 규모를 억제하고, 국방중기계획의 실효성을 증대시킬 수 있는 방안을 강구하며, 북한에 대한 제재를 강화하면서 평화협상 노력을 병행해 가는 것이 필요하다. 이러한 정책 레버리지를 통해 방위력개선비를 증가시켜 국방중기계획에서 달성하고자 하는 전력증강을 이룰 수 있을 것이다. 본 연구는 정책결정자와 실무 담당자들이 피드백 루프를 항상 고려하는 시스템 사고에 바탕을 두어 방위력개선비를 결정하게 하는 계기가 될 수 있다는 데 의의가 있다. The purpose of this study is to provide policy-makers with reasonable judgment grounds for the force improvement budget by identifying structural problems of the system and drawing out policy leverage strategies. Based on the theory of defense budget determination and preceding researches, six determinants of force improvement budget in Korea that directly affect the force enhancement were selected: the Korea-U.S. alliance, policy will, decision-making system, national economic capability, threats from North Korea and threats from neighboring countries. And the causalities among them were analyzed by drawing up causal loop diagrams using system thinking. According to the analyses, policy leverage strategies were indentified as follows: To curb the size of defense burden sharing, to devise a solution to increase the effectiveness of the mid-term defense plan, and to continue peace-negotiation efforts while further tightening sanctions on North Korea. By doing so, it would be possible to increase the force improvement budget and achieve the desired force enhancement. This study would be contributable for policymakers and policy practitioners to determine the force improvement budget based on system thinking that always considers feedback loops.

Web Framework 기반의 교내 소셜 네트워크 서비스

김광석(Kim Kwang-Seok),이은택(Lee Eun-Tae),임미숙(Lim Mi-Suk),김윤호(Kim Yoon-Ho) 한국정보기술학회 2018 Proceedings of KIIT Conference Vol.2018 No.11

LNG연료 추진선용 IMO Type-B 목업 탱크의 설계 및 시험방법

김광석(Kwang Seok Kim) 한국가스학회 2017 한국가스학회 학술대회논문집 Vol.2017 No.5

목표설정 수준이 축구슈팅 수행력 및 신체적 자기효능감에 미치는 영향

김광석 ( Kwang Seok Kim ),한태준 ( Tae Joon Han ),정인철 ( In Chul Jeong ) 동의대학교 스포츠과학연구소 2002 스포츠과학연구논문집 Vol.1 No.-

The purpose of this was aimed to verify the effects of assigned goal setting on sport performance and physical self-efficacy. For this study 60 members of male high-school students are allocated into three groups. Namely, the group was assigned with upper level goal(n=20), lower level goal(n=20), and control(n=20) respectively. The soccer program was put into two times a week during eight weeks. The pre test was performed by using Soccer wall accuracy test and Physical Self-Efficacy before the soccer program. The post test was carried eight weeks after the soccer program was finished. Two-way ANOVA and Duncan`s Multiple Range test used in order to deal with the materials. In addition to these paired t-test also was used. The level of significance of all hypothesis tests wasα=.05 and the write got result as follow. 1) The performing records of soccer wal accuracy test in the group with upper level advanced significantly more than those who lower level and control groups. 2) The level of anterior and posterior perceived physical self-presentation confidence in the group with upper goal, the group with lower goal, and control group were shown significant difference. 3) The level of anterior and posterior perceived physical ability in the group with upper goal, the group with lower goal, and control group were shown significant difference. 4) The level of anterior and posterior physical self-efficacy in the group with upper goal, the group with lower goal, and control group were shown significant difference. 5) There was no effect of interaction between goal level and neither reached goal or not.