로봇 팔의 뇌 신호로부터 유도된 3D 좌표 추적을 위한 Guidance Law 적용에 관한 연구

김윤재,박성우,김원식,염홍기,서한길,이용우,방문석,정천기,오병모,김준식,김유단,김성완,Kim, Y.J.,Park, S.W.,Kim, W.S.,Yeom, H.G.,Seo, H.G.,Lee, Y.W.,Bang, M.S.,Chung, C.K.,Oh, B.M.,Kim, J.S.,Kim, Y.,Kim, S. 대한의용생체공학회 2014 의공학회지 Vol.35 No.3

It is being tried to control robot arm using brain signal in the field of brain-machine interface (BMI). This study is focused on applying guidance laws for efficient robot arm control using 3D coordinates obtained from Magnetoencephalography (MEG) signal which represents movement of upper limb. The 3D coordinates obtained from brain signal is inappropriate to be used directly because of the spatial difference between human upper limb and robot arm's end-effector. The spatial difference makes the robot arm to be controlled from a third-person point of view with assist of visual feedback. To resolve this inconvenience, guidance laws which are frequently used for tactical ballistic missile are applied. It could be applied for the users to control robot arm from a first-person point of view which is expected to be more comfortable. The algorithm which enables robot arm to trace MEG signal is provided in this study. The algorithm is simulated and applied to 6-DOF robot arm for verification. The result was satisfactory and demonstrated a possibility in decreasing the training period and increasing the rate of success for certain tasks such as gripping object.

강유전 박막에서의 분극역전과정 예측

김상주(Sang-Joo Kim),신준호(Joonho Shin),김윤재(Yun-Jae Kim) 대한기계학회 2002 대한기계학회 춘추학술대회 Vol.2002 No.3

A two-dimensional finite element model for polarization switching in ferroelectric materials developed by Kim and Jiang<SUP>(1)</SUP> and Sang-Joo Kim<SUP>(2)</SUP> is used to predict the formation of domains in a ferroelectric thin film. Initially the ferroelectric film is poled upward and the bottom electrode is grounded. A strong downward de field is imposed on a point of the top surface of the film. A region of switched domains with downward polarization is nucleated and is grown with time. It is found that initially the shape of the nucleated domains is that of a bulgy dagger, but later it turns into the shape of a reversed cup with the lower part wider than the upper part. It can also be concluded that the size of nucleated domains increases with the period of applied electric potential. The present results are qualitatively consistent with experimental observations.

미래 복지체계의 방향성에 관한 연구

김윤재,금기윤,Kim, Youn-Jae,Keum, Ki-Youn 한국벤처창업학회 2011 벤처창업연구 Vol.6 No.4

한국을 포함하여 세계적으로 국가경제의 외부환경은 급속도로 빠르게 변화하고 있음에도 복지체계 및 복지정책 방향은 과거의 틀에서 크게 벗어나지 못하고 있다. 그 결과 복지 및 경제사회 관련 쟁점들은 정책의 목표를 둘러싼 이념적 충돌로 그치거나, 정합성이 결여되거나, 이해집단의 개입과 갈등이 지속되는 결과만을 초래하고 있다. 과거 우리나라의 복지는 성장을 통해 해결할 수 없는 부분을 보완하는 수준이었다. 높은 성장률로 고용창출이 지속적으로 이루어졌고 낮은 노령화 수준과 젊은 인구구조, 높은 출산율 등이 이를 뒷받침하는 구조였다. 그러나 현재의 새로운 국내외 경제사회 복지환경은 새로운 복지정책 변화를 요구하고 있다. 경제사회정책 목표는 안정적 경제사회시스템 구축과 복지확산형 사회투자형 복지국가를 지향하는 경제사회정책의 구성이 요구되고 있다. 또한 향후 한국 복지제도 강화의 방향은 보장성(protection) 강화와 역동성(activation) 강화 사이에 균형이 이루어져야 하며, 사후적 복지에서 예방적 복지로 전환이 되어야 할 필요성이 있다. 또한, 공공부문 민간시장 개인의 역할분담이 이루어져야 하며, 잔여적 복지에서 보편적 복지로의 패러다임의 전환이 이루어져야 할 필요성이 있으며, 이와 같은 복지제도의 개선을 통해 장기적으로 제도의 지속가능성을 높일 수 있을 것이다. The welfare system and the direction of the welfare policy have been unable to escape greatly from the frame of the past against the facts that the external environments of the national economy of the world including Korea have been changing in quick and rapid speed. Such results have caused the issues related with the welfare, economy and society ended in the ideological collision in connection with the goals of the policy, the right agreement between the policies lacked, and the intervention and conflict between the interest group concerning the policy continued. Social policy of Korea in the past had the level of complementing the parts which could not be solved through the growth. Employment creation had been achieved continuously backed up by the high rate of growth. And the low aging level, the young population structure, and the high rate of childbirth had been the structures that made such achievement possible. New economic, social and welfare environment at home and abroad has been requesting new change in welfare policy. Goal of the economic and social policy is to construct the safe economic and social system. And what has been requested has been the formation of the economic and social policy orienting the welfare nation in form of social investment and welfare expansion. Also the direction in strengthening the welfare system of Korea shall have the balance between the protection and activation strength with the necessity of converting to the prevention welfare from the post welfare. Also the public part, market, the 3rd sector and the share of the role of an individual shall be achieved. And what is needed is the achievement of the transfer from the paradigm of residual welfare to the universal welfare. And such improvements of the welfare system will be able to elevate the possible continuity of the system in long term basis through the improvement of the welfare system.

무구속적 방법으로 측정된 심전도의 신뢰도 판별

김윤재,허정,박광석,김성완,Kim, Y.J.,Heo, J.,Park, K.S.,Kim, S. 대한의용생체공학회 2016 의공학회지 Vol.37 No.5

Recent technological advances in sensor fabrication and bio-signal processing enabled non-constraint and non-intrusive measurement of human bio-signals. Especially, non-constraint measurement of ECG makes it available to estimate various human health parameters such as heart rate. Additionally, non-constraint ECG measurement of wheelchair user provides real-time health parameter information for emergency response. For accurate emergency response with low false alarm rate, it is necessary to discriminate quality levels of ECG measured using non-constraint approach. Health parameters acquired from low quality ECG results in inaccurate information. Thus, in this study, a machine learning based approach for three-class classification of ECG quality level is suggested. Three sensors are embedded in the back seat, chest belt, and handle of automatic wheelchair. For the two sensors embedded in back seat and chest belt, capacitively coupled electrodes were used. The accuracy of quality level classification was estimated using Monte Carlo cross validation. The proposed approach demonstrated accuracy of 94.01%, 95.57%, and 96.94% for each channel of three sensors. Furthermore, the implemented algorithm enables classification of user posture by detection of contacted electrodes. The accuracy for posture estimation was 94.57%. The proposed algorithm will contribute to non-constraint and robust estimation of health parameter of wheelchair users.

원주방향 관통균열이 존재하는 배관의 J-적분 및 COD 계산을 위한 새로운 공학적 계산식

김윤재,허남수,김영진,Kim, Yun-Jae,Heo, Nam-Su,Kim, Yeong-Jin 대한기계학회 2001 大韓機械學會論文集A Vol.25 No.3

A new method to estimate the elastic-plastic J-integral and the crack tip opening displacement (COD) for circumferential through-wall cracked pipes under tension and under bending is proposed for Leak-Before-Break (LBB) analysis. Being based on the reference stress method with further modifications, the proposed method is simple to use and easy to be generalised in practice. Comparison of the CODs, predicted using the proposed method with published pipe test data show overall excellent agreement.

압력용기 수명 평가 기술 및 규격

김윤재,송태광,이국희,Kim, Yun-Jae,Song, Tae-Kwang,Lee, Kuk-Hee 대한용접접합학회 2010 대한용접·접합학회지 Vol.28 No.2

지역사회복지관의 기능전환에 따른 정체성 확립방안 연구

김윤재,금유현,Kim, Youn Jae,Kum, You Hyun 한국벤처창업학회 2013 벤처창업연구 Vol.8 No.1

2011년 사회복지사업법 개정, 2012년 사회복지사업법 시행규칙이 개정됨으로써 지역사회복지관의 기능이 사례관리기능, 서비스제공기능, 지역사회조직화기능의 3대 기능으로 재조정이 이루어졌다. 그에 따라 지역사회복지관은 2013년부터 지역사회복지관에 요구되는 기능과 역할, 그에 부합하는 사업 및 프로그램과 서비스, 조직체계를 정비하면서 지역사회복지의 핵심적 주체로서의 위상을 새롭게 정립해나가야 하는 과제를 안게 되었다. 그러나 현재 지역사회복지관이 본연의 기능을 수행하는데 있어서는 내외적 제약요인이 작용하고 있다. 외부적으로는 유사기관과의 경쟁, 사회환경의 변화에 따른 복지욕구의 다양화, 서비스네트워크 구축의 미흡, 민관파트너십의 부재 등이 있으며 내부적 제약요인으로는 지역사회조직화 역량의 부족, 프로그램 문제, 자원의 부족, 인력의 부족, 등이 자리잡고 있다. 이러한 제약요인들을 극복하면서 지역사회복지관이 지역주민의 삶의 질 향상을 위한 중추적 위상을 정립하기 위해서는 지역사회조직화사업에 복지관의 역량 집중, 지역사회복지 관련 인적 물적 자원네트워크 구축, 사회교육프로그램가 단순구호사업의 점진적인 축소, 주민조직의 육성 마을만들기의 바람직한 방향 제시, 지역주민 욕구조사에 토대한 프로그램 개발, 민관파트너십 형성노력 등이 요구된다. As Social Welfare Service Act was revised in 2011 and its enforcement decree was revised in 2012, the function of local social welfare center was classified into 3 functions such as case control function, service supply function and local society systematization function. Therefore, from 2013, local social welfare center faces the assignment to establish its status as a core subjectivity of local social welfare while maintaining function, role, business, program, service and organization system required for local social welfare center. Currently, there are internal and external limit factors for local social welfare center to perform its original function. The external limit factors are competition with similar organization, diversification of welfare desire depending on social change, insufficient service network construction and lack of partnership between private sector and government. The internal limit factors are lack of local social organization's ability, program issue, insufficient resource, insufficient manpower, etc. In order for local social welfare center to overcome the limit factor and establish the core status for improving the life quality of resident, it should concentrate its ability on local society systematization, construct human & material support network related to local social welfare, minimize social education program and simple relief project gradually, suggest the reasonable direction for village to nurture resident organization, develop the program based on the research on local resident's desire and create the partnership between private sector and government.

감마카메라의 중장기 외인성 균일도 분석

김윤재,정우영,이동훈,Yoon-Jae Kim,Woo-Young Jung,Dong-Hoon Lee 대한핵의학기술학회 2023 핵의학 기술 Vol.27 No.1

Purpose The long-term trend of extrinsic uniformity by type of gamma camera was analyzed, and the factors affecting uniformity were investigated. Based on this, the purpose was to predict the life of the gamma camera, pay attention to factors that affect uniformity, and obtain better quality images. Materials and methods Four of the gamma cameras in operation at a senior general hospital in Seoul were selected and the trend of extrinsic uniformity from the first operation date to the present was analyzed. In order to minimize various factors affecting uniformity, a detailed analysis was conducted by calculating the monthly and annual average of the uniformity values. Results Two Symbia E gamma cameras from SIEMENS, one Symbia Evo Excel gamma camera, and one Symbia Intevo16 gamma camera were selected and analyzed. The uniformity of Symbia E₁ (2012 warehousing) changed unevenly, and the uniformity of Symbia E₂ (2014 warehousing) changed according to the replacement cycle of ⁵⁷Co sheet sources. The uniformity of Symbia Evo Excel (received in 2017) and Symbia Intevo 16 (received in 2017) was constant compared to Symbia E. Conclusion The extrinsic uniformity of the gamma camera gradually increased over time. However, there was a difference in uniformity for each type of gamma camera, and there was a change in uniformity in which the cause could not be accurately identified. In order to improve the quality of the image, it is necessary to periodically check changes in uniformity and minimize factors that affect uniformity.

초고온 고세균 Thermococcus pacificus P-4로부터 내열성 β-glucosidase의 새로운 기질 특이성

김윤재,이재은,이현숙,권개경,강성균,이정현,Kim, Yun Jae,Lee, Jae Eun,Lee, Hyun Sook,Kwon, Kae Kyoung,Kang, Sung Gyun,Lee, Jung-Hyun The Microbiological Society of Korea 2015 미생물학회지 Vol.51 No.1

Thermococcus pacificus P-4의 유전체 서열 분석을 통하여 예측되는 GH1 ${\beta}$-glucosidase를 암호화하는 유전자를 동정하였다. 그 유전자는 487 아미노산들을 암호화하는 1,464 bp 나타내었으며, 그 아미노산 서열은 Pyrococcus furiosus ${\beta}$-glucosidase와 77% 상동성을 나타내었다. 그 유전자는 Escherichia coli 시스템 내에서 복제 및 발현하였다. 재조합 된 단백질은 금속 친화크로마토그래피를 통하여 정제하고 특성을 분석하였다. 정제된 단백질(Tpa-Glu)은 pH 7.5와 $75^{\circ}C$에서 최적활성을 나타내었으며, 열안정성은 $90^{\circ}C$에서 약 6시간의 반감기를 보였다. Tpa-Glu는 pNP-${\beta}$-glucopyranoside, pNP-${\beta}$-galactopyranoside, pNP-${\beta}$-mannopyranoside, 그리고 pNP-${\beta}$-xylopyranoside 순으로 우수한 $k_{cat}/K_m$ 값을 나타내었다. 또한, Tpa-Glu는 ${\beta}$-1,3-linked polysaccharide (laminarin) 그리고 ${\beta}$-1,3-와 ${\beta}$-1,4-linked oligosaccharides에 대하여 exo-hydrolyzing 활성을 보였다. 본 연구는 초고온 고세균으로터 ${\beta}$-glucosidase가 exohydrolyzing 활성을 처음 확인한 것으로 이 효소는 laminarin의 당화공정에 ${\beta}$-1,3-endoglucanase와 함께 적용할 수 있을 것으로 기대된다. Based on the genomic analysis of Thermococcus pacificus P-4, we identified a putative GH1 ${\beta}$-glucosidase-encoding gene (Tpa-glu). The gene revealed a 1,464 bp encoding 487 amino acid residues, and the deduced amino acid residues exhibited 77% identity with Pyrococcus furiosus ${\beta}$-glucosidase (accession no. NP_577802). The gene was cloned and expressed in Escherichia coli system. The recombinant protein was purified by metal affinity chromatography and characterized. Tpa-Glu showed optimum activity at pH 7.5 and $75^{\circ}C$, and thermostability with a half life of 6 h at $90^{\circ}C$. Tpa-Glu exhibited hydrolyzing activity against various pNP-glycopyranosides, with kcat/Km values in the order of pNP-${\beta}$-glucopyranoside, pNP-${\beta}$-galactopyranoside, pNP-${\beta}$-mannopyranoside, and pNP-${\beta}$-xylopyranoside. In addition, the enzyme exhibited exo-hydrolyzing activity toward ${\beta}$-1,3-linked polysaccharide (laminarin) and ${\beta}$-1,3- and ${\beta}$-1,4-linked oligosaccharides. This is the first description of an enzyme from hyperthermophilic archaea that displays exo-hydrolyzing activity toward ${\beta}$-1,3-linked polysaccharides and could be applied in combination with ${\beta}$-1,3-endoglucanase for saccharification of laminarin.

보육교사 직무만족이 조직몰입에 미치는 영향요인 분석

김윤재,남궁선,강영숙,Kim, Youn Jae,Namkoong, Sun,Kang, Young Sook 한국벤처창업학회 2014 벤처창업연구 Vol.9 No.4

본 연구는 어린이집에서의 보육교사 역할의 중요성에 대한 인식 확산 및 시설이 확대되는 시점에서 어린이집에서 근무하는 보육교사들을 대상으로 조직몰입에 대해 스스로 어떻게 평가하고 있는지를 살펴보고, 이에 영향을 미치는 요인이 무엇인지 살펴보았다. 서울지역 어린이집에서 근무하는 보육교사를 대상으로 직무만족 자기인식 요인과 원장의 리더십 자기인식 요인, 인구통계학적 특성, 직장관련 특성 요인들이 조직몰입(정서적 몰입, 규범적 몰입, 지속적 몰입)에 영향을 미치는 요인들을 분석하였다. 분석 결과 직무만족, 개별적 고려, 지적 자극, 동기부여, 연령, 학력, 시설유형, 시설규모, 직급 등이 조직몰입에 대한 자기평가에 통계적으로 유의미한 영향을 미치는 것으로 나타났다. 즉, 보육교사는 원장의 지적 자극을 올리는 리더십, 동기부여를 제공하는 원장의 리더십, 교사 개인별로 배려를 해주는 원장의 리더십을 접할수록, 그리고 보육교사 개인이 인지하는 직무만족 자기평가가 높을수록 조직몰입에 반응정도가 긍정적인 방향으로 영향을 미칠 것이다. 이를 바탕으로 어린이집 원장은 보다 적극적 및 교사 배려적 운영을 위한 리더십을 펼치는 한편, 보육교사들의 직무만족 향상을 위한 다양한 경영서비스 제공 및 개발이 요구된다고 할 것이다. This study has examined how the childcare teachers have been evaluating themselves on system absorption who have been working in the house of the children at the time when the sight of the society has been expanding to the house of the children through the spread of the understanding of the importance of the role and the strengthening of the leadership of the diverse types of the leadership of the childcare teachers in the house of the children, and also this study has observed the main causes affecting such situations. This study has also analyzed the main causes such as the cause of self understanding on job satisfaction of the children's house teachers, the cause of self understanding on the leadership of the principal, demographic characters, and characters related with the place of work affecting the system absorption(Emotional Absorption, Normative absorption, and lasting absorption) with the children's house teachers as the objects working in the area of the City of Seoul. The results of the analysis have showed that job satisfaction, individual consideration, intellectual stimulation, giving motive, age, schooling, type and scale of facility, grade and others have been appeared to have been significantly affecting the self evaluation on system absorption demographically. In other words, the child care teachers have had higher degree of reaction to the system absorption in affirmative direction when they come into contact with the leadership of the principal in raising the intellectual stimulation, providing the motivation, and giving consideration individually, and when they have higher evaluation on the job satisfaction they them selves understand. Based on such results the principal of the house of the children should spread the leadership for the careful operation of the house of the children for the teachers more positively, and what has been required was giving and developing the diverse operation service for the elevation of the job satisfaction of the childcare teachers.