진동절연 장치를 이용한 인공위성 반작용휠 미소진동 절연 특성 시험

김대관(Dae-Kwan Kim) 한국소음진동공학회 2017 한국소음진동공학회 학술대회논문집 Vol.2017 No.10

분산 전구체를 이용한 Diarylide계 안료의 합성 및 분산거동

김송혁 ( Song Hyuk Kim ),김재환 ( Jae Hwan Kim ),양석원 ( Seok Won Yang ),김대성 ( Dae Sung Kim ),이근대 ( Gun Dae Lee ),박성수 ( Seong Soo Park ) 한국공업화학회 2014 공업화학 Vol.25 No.6

In this study, the diarylide compound pigment of high hiding power and vivid color was synthesized successfully by controlling several factors such as pH, coupler solution temperature, kind and addition amount of dispersion precursor, and crystallization temperature in the process of coupling synthesis. The properties of samples were measured by the means of FT-IR, UV-Vis spectroscopy, PSA, zeta potential, and turbiscan. It was found that the highly dispersive sample could be prepared by introducing the dispersive precursor.

기술격차에 따른 기술무역과 상품무역에 대한 연구

김연대(Yeon-Dae Kim),손지은(Ji-Eun Son),손성문(Seong-Mun Son) 인문사회과학기술융합학회 2018 예술인문사회융합멀티미디어논문지 Vol.8 No.8

기술격차로 인해서 발생되는 기술무역의 파생효과와 기술무역에 따른 기술무역수지를 살펴보고 기술무역과 상품무역의 상관관계에 대해서 알아보고자 한다. 우리나라와 주요국 사이의 기술 격차가 가져다주는 기술무역의 현황과 기술무역의 수지를 파악하여 상품무역에 영향을 미치는 기술무역의 역할을 연구해보고자 한다. 그리고 국가전략기술 전체의 주요국 기술수준 변동과 국가전략기술의 주요국 기술격차 변동을 파악한 다음 국가전략기술 전체의 기술수준 과 기술격차 변동을 함께 동시에 살펴봄으로서 우리나라의 기술무역이 차지하는 비중을 알아보고자 한다. 기술 격차에 따른 기술도입은 기술무역수지의 적자를 유발하면서도 상품 생산성 증대로 인하여 상품무역 수지 흑자를 유발하여 정의 효과를 가져다주는 순기능을 하고 있음을 발견할 수 있었다. 상품수출 증가에 따라 선진국으로부터 기술도입에 따른 기술비용증가로 기술무역수지 적자규모가 커지더라도 기술무역 규모의 확대는 상품무역 수지 개선을 통해 경제성장에 올바른 영향을 미치고 있음을 확인하였다. This study examines the effect of technology trade on technological trade gap and the relation between technology trade and commodity trade. This study examines the status of technology trade brought about by the technological gap between Korea and major countries, and studying the role of technology trade affecting commodity trade by identifying the balance of technology trade. The purpose of this study is to investigate the technological level and the technological gap between the major countries of the national strategic technology, and the proportion of Korea s technology trade. The introduction of technology according to technological gap has been found to cause a deficit in the trade balance of technology, but it has a positive effect of bringing about a positive effect by inducing a trade surplus of commodity due to increase of product productivity. It is confirmed that the expansion of the volume of technology trade has a positive effect on the economic growth through the improvement of the trade balance of goods even if the technical trade deficit is increased due to the increase of technology costs due to the introduction of technology from developed countries.

짧은 보강재를 사용한 철도보강노반의 시공 중 안정성 평가

김대상(Dae Sang Kim) 한국지반신소재학회 2014 한국지반신소재학회 논문집 Vol.13 No.4

짧은 보강재를 적용한 강성벽 일체형 보강노반의 시공 중 거동에 대하여 고찰하고 안정성을 평가하였다. 우선 시공하중 상태에서 안정성이 확보될 수 있는 최소보강재 길이에 대한 이론적 고찰을 수행하고, 기존 설계기준 적용 보강재 길이(70%, 0.70H)와 짧은 보강재(35%, 0.35H) 및 장 보강재를 혼용하는 보강재 설치 패턴에 대한 경제성을 비교하였다. 높이의 30%(0.30H), 35%(0.35H), 40%(0.40H) 적용 보강노반의 시공 중 안정성을 검증하기 위하여 실물 단선용 철도노반 높이*폭*길이(5m*6m*20m)에 대한 현장시공을 실시하였다. 총 51개의 센서를 노반 내부 및 보강재에 설치하여 침하, 배부름 및 응력 변화를 확인하였다. 이를 통하여 짧은(0.35H, 높이의 35%) 지오그리드를 적용한 보강노반의 변형 및 발생 응력수준이 시공 중 안정성을 확보할 수 있는 허용범위 이내인 것을 확인할 수 있었다. The behaviors and stability of reinforced subgrade with short geogrid were examined and evaluated during construction. First of all, analytical approach for the minimum length of geogrid was performed to guarantee stability during construction loading state. Secondly, the economic aspects for reinforced subgrade were compared with between domestic standards applying with 0.7 H reinforcement length and new way to mix short and long reinforcement. Full scale railroad subgrade was constructed with the size of 5 m high, 6m wide, and 20m long to verify the stability of the subgrade with the length of 0.3 H, 0.35 H, 0.4 H reinforcement. Total 51 sensors were installed to measure settlement, bulging, and the change of stress of the subgrade. It is concluded that the reinforced subgrade with short(0.35H, 35% of height) geogrid had stability within allowable level of deformation and stress increment during construction.

고주파 열처리 코일과 피가열물 사이 간극에 따른 SCM440 강의 고주파 열처리 특성에 관한 연구

김대완(Dae-Wan Kim),최지석(Jee-Seok Choi),한창원(Chang-Won Han),이무연(Moo-Yeon Lee) 한국산학기술학회 2017 한국산학기술학회논문지 Vol.18 No.10

본 논문에서는 자동차에서 사용되는 부품 중 Sway bar link에 사용되는 볼 스터드의 고주파 열처리 시 고주파 열처리 코일과의 사이 간극에 따른 고주파 열처리 특성에 관하여 연구하였다. 오늘날 세계 완성차 업체는 소비자의 요구와 각 국가의 환경정책에 따라 연비향상 및 배기가스 감축함과 동시에 고성능의 자동차를 개발하기 위하여 많은 연구를 하고 있다. 그러나 고주파 열처리에 대한 대부분의 연구가 실험적으로 이루어지고 있어 특정 제품에 맞는 열처리 조건을 구하기가 매우 어렵다. 이러한 문제로 인하여 본 연구에서는 고주파 열처리 조건 중 고주파 열처리 코일과 피가열물 사이 간극을 제외한 모든 조건은 동일하게 유지하여 열처리를 하고, 표면경도와 유효경화깊이 및 전경화깊이를 측정하여 최적의 고주파 열처리 코일과 피가열물 사이 간극은 1~2 mm 임을 알아내었다. 또한 고주파 열처리 코일과 피가열물 사이 간극이 3 mm 이상일 때는 유효경화깊이 및 전경화깊이의 기준 값을 만족하지 못하였다 This study investigatesthe high-frequency heat treatment characteristics with the distance between a coil and SCM440 parts for an automobile. Global automobile makers are focusing on research to develop high-performance automobiles with improved fuel efficiency and lower emissions in accordance with consumer demand and environmental policies. However, most research onhigh-frequency heat treatment has been experimental, and it is very difficult to obtain high-frequency heat treatment conditions for a specific product. Therefore, all the conditions of high-frequency heat treatment except the distance between a coil and SCM440 parts were kept the same. As a result, the optimized distance between the coil and SCM440 parts was observed to be 1-2 mm. When the distance between the coil and SCM440 parts was over 3 mm, the effective case hardness depth and total case hardness depth did not satisfy the standards..

수지 충전 공정을 이용한 항공기 윈도우 프레임 설계

김위대 ( Wie Dae Kim ),홍대진 ( Dae Jin Hong ) 한국복합재료학회 2006 Composites research Vol.19 No.6

Isoindoline계 황색 화합물의 환경친화적 합성 및 이의 특성

김송혁 ( Song Hyuk Kim ),김재환 ( Jae Hwan Kim ),양석원 ( Seok Won Yang ),이원기 ( Won Ki Lee ),이근대 ( Gun Dae Lee ),박성수 ( Seong Soo Park ) 한국공업화학회 2015 공업화학 Vol.26 No.1

In this study, to obtain isoindoline compounds with the high thermal resistance and reddish yellow color using an environmental friendly method without the use of any surfactants, isoindoline derivatives with different structures were added at various reaction temperatures for the synthesis and the product was then crystallized by controlling temperatures and times in autoclave. Chemical structures, particle sizes, color differences, and optical properties were evaluated by the means of FT-IR, FE-SEM, UV-Vis spectroscopy, PSA (particle size analyzer) and Zeta potential analyzer. The samples with an enhanced dispersibility, highly thermal resistance, uniform particle sizes were achieved possibly due to the addition of isoindoline derivatives into the crystallization processing mixtures. The color change trend was also observed depending upon synthesis conditions.

전력계통용 8채널 광기반 센서 노드 개발

김대길(Dae-gil Kim),박시웅(Si Woong Park),김계은(Kyeeun Kim),강현서(Hyun Seo Kang),박형준(Hyoung Jun Park) 대한전기학회 2022 대한전기학회 학술대회 논문집 Vol.2022 No.10

폐경 전 여성의 비만이 자율신경계 활성도 변화에 미치는 영향

김대필 ( Dae Feel Kim ),금동호 ( Dong Ho Keum ) 한방재활의학과학회 2006 한방재활의학과학회지 Vol.16 No.1

Objectives : This study was designed to evaluate the influence of obesity on autonomic nervous system activity. Methods : This clinical study have been carried out with premenopausal 59 women that entered Dong-Guk university Bun-Dang oriental medicine hospital from January, 2004 to May, 2005. 59 women were divided into 27 women non-obese group(<BMI 25) and 32 women obese group(.BMI 25). Results : 1. MHRT, SDNN, RMSSD which obtained by time domain analysis were significantly decreased in obese group. 2. TP, LF, HF, LF/HF ratio which obtained by frequency domain analysis were decreased in obese group, HF was significantly decreased but othres were no significant differences between non-obese group and obese group. Conclusions : These results suggest that both sympathetic and parasympathetic activity were decreased in obese premenopausal women.

프로스포츠 팀 감독의 전략적 리더십과 프로스포츠 팀 경영

김대권(Kim, Dae-Kwon),김필수(Kim, Phil-Soo),신태용(Shin, Tae-Yong) 한국사회체육학회 2015 한국사회체육학회지 Vol.0 No.61

This study seeks to explore the strategic leadership of head coaches and their management in Korean professional sport team. By conducting a qualitative methodology of an in-depth semi-structured interviews with head coaches in diverse professional sport teams in the field of soccer, basketball, and volleyball, we find several research findings that are as followed. First, experience assets accumulated in foreign leagues that head coaches embeds expand insights of strategic leadership to manage the focal team with a horizontal relationship orientation. Second, leadership practice previously performed as captain of the team when they were active players in the past encourage talent management to strengthen coaching career. Third, our results also indicate that each head coach possess unique leadership characteristic to aggregate team players that directly enhance team performance. Forth, accumulated know-hows throughout their coaching careers supplement team management by maintaining the quality of players’ performance that can be integrated in a synergy format to create team spirit. Fifth, some head coaches participate in team management as upper echelons to effectively allocate limited financial budget.