도둑놈의 갈고리로부터 생산된 항비만성 Lipase 저해제와 시판 Lipase 저해제의 활성 비교

이종국 ․ 강민구 ․ 이종수 배재대학교 자연과학연구소 2011 自然科學論文集 Vol.22 No.1

Obesity is the cause of various diseases including high blood pressure, diabetes, hyperlipidemia, and cerebrovascular accidents. Therefore, development of new anti-obesity nutraceuticals or drugs is necessary. In previous paper, we selected Desmodium oxyphyllum as a potent lipase inhibitor-containing herb. In this study lipase inhibitory activity of Desmodium oxyphyllum and commercial lipase inhibitor were determined and compared. Lipase inhibitory activity of extract from Desmodium oxyphyllum showed 67.4%, whereas commercial lipase inhibitor showed more high 85.3% rater than that of Desmodium oxyphyllum.

MRAC를 이용한 2 자유도 구륜 이동로보트의 경로추적

문종우,김원규,박종국 경희대학교 자연과학종합연구원 1997 자연과학논문집 Vol.3 No.-

본 논문은 2 자유도 구륜 이동로보트의 기구학 모델과 기준모델 적응제어기 설계를 다루었다. 구륜 속도와 본체 속도를 계산하기 위하여 정기구학(forward kinematics)과 역기구학(inverse kinematics)를 유도하였으며, 제어변수의 수와 제어입력의 수가 동일하게 되도록 제어변수를 극좌표로 변환하였다. 구륜 이동로보트의 경로추적을 위한 제어기를 제안하였으며, 제어기 매개변수는 기준모델 적응제어(reference-model adaptive control, MRAC)에 기초한 적응법칙(adaptation law)에 의해 매 단계마다 갱신된다. 설계된 적응제어기를 분석하고, 제어 시스템의 안정성과 수렴성을 증명한다. 제어시스템의 유효성을 입증하기위해 모의실험을 수행하고, 그 결과를 제시한다. This paper presents the kinematic model and the design of a model-reference adaptive controller for wheeled-mobile robots(WMRs) with 2 d.0.f. We derive the forward kinematics and the inverse kinematics to calculate the wheel-velocity and body-velocity. The controlled variables are represented in the polar coordinate so that the number of the controlled variable can be reduced to the same number as the control input. A controller is proposed for path tracking, and then controller parameters are modified by adaptation law based on reference-model adaptive control(MRAC) each step. The adaptive controller is analyzed, and its stability and convergence are proved. Simulation is conducted to prove efficiency of the control system and the results are showed.

방향성 마스크를 이용한 손실 영상 복원

함종국,이용학 제주대학교 공과대학 첨단기술연구소 2002 尖端技術硏究所論文集 Vol.13 No.2

In this paper, the interpolation method using direction mask is proposed. After inserting zero into the loss area of the edge image, the information of the direction and the similar intensity property of the edge are obtained by the direction mask and the interpolation is performed from the estimated information. To analyze the performance of the proposed method, three images which have different loss areas are selected and the interpolated images by the proposed method have the improved PSNR about 4∼5㏈ and the reduced blur effect than compare to the conventional linear interpolation method.

구륜이동로보트의 기구학 모델의 극좌표 변환과 기준모델 적응제어에 기초한 경로추적 제어기 설계

金鍾寓,金元圭,朴鍾國 경희대학교 산학협력기술연구원 1997 산학협력기술연구논문집 Vol.3 No.-

This paper presents the kinematic model and the design of a model-reference adaptive controller for wheeled-mobile robots(WMRs) with 2 d.o.f. We derive the forward kinematics and the inverse kinematics to calculate the wheel-velocity and body-velocity. The controlled variables are represented in the polar coordinate so that the number of the controlled variable can be reduced to the same number as the control input. A controller is proposed for path tracking, and then controller parameters are modified by adaptation law based on model-reference adaptive control(MRAC) each step. The designed adaptive controller is analyzed, and its stability and convergence are proved Simulation is conducted to evaluate the control system and the results are presented

기구학적 불완전성을 갖는 구륜이동로보트의 기구학적 보정과 방향각 오차의 감소를 위한 속도 궤적의 설계

문종우,김원규,박종국 慶熙大學校 材料科學技術硏究所 1998 材料科學技術硏究論集 Vol.11 No.-

This paper presents the kinematic correction method for wheeled-mobile robots with 2 d.o.f. and a design of the velocity trajectory for wheeled-mobile robots'line-travelling. We derive the relative wheel-weight and the absolute wheel-weight to correct the radius of both wheels. And we use the curvature angle to correct displacement of wheel base. We show that wheeled-mobile robots can't move along a straight-line perfectly and the velocity trajectory must have the chage of velocity at least one. To prove efficiency of the method in this paper, we experiment on the wheeled-mobile robots with 2 d.o.f. and discuss the results.

추간판 응력분포에 대한 광탄성 해석

신현국,이재창,안면환,안종철,인주철 영남대학교 의과대학 1989 Yeungnam University Journal of Medicine Vol.6 No.2

요추의 중립위, 굴곡위 및 신전위에서의 응력 분포의 차이와 수핵의 유무에 따른 응력 분포의 변화를 관찰하기 위해 본 연구를 시행 하였으며 등색선의 양상을 관찰하고 그 응력을 해석하여 다음과 같은 결론을 얻었다. 1. 기립 중립위에서는 수핵이 있는 경우는 전방 부위보다 후방부위에 고응력이 집중되었으며, 전후방 모두 내측부와 중간부위가 고응력이고 외측부로 이동할수록 적응력이 관찰되었다. 수핵이 없는 경우는 후방보다 전방부에 고응력이 집중되었으며 국소적으로 응력이 집중되는 양상을 보이고 있다. 2. 최대 굴곡위에서는 수핵의 존재에 관계없이, 전방보다 후방부에 고응력이 집중되었으며, 수핵 유무 비교시 수핵이 있는 경우가 없는 경우보다 전방이 저응력, 후방은 거의 동등한 응력 분포를 나타냈었다. 응력 분포도의 분석에 의하면 전반적으로 균등한 응력 분포 양상을 나타냈다. 3. 최대 신전위에서는 수핵 유무에 관계없이 전방부에 고응력, 후방부에 저응력, 내측에 고응력, 외측은 저응력을 나타내었으며, 수핵이 있는 경우 없는 경우보다 고응력을 나타냈다. 4. 기립 중립위와 최대 굴곡위의 비교에서는 기립 중립위보다 굴곡시 수핵의 유무에 관계없이 전반적으로 후방부 응력이 2차 정도 현저히 감소하는 양상을 보이면서 비교적 균등한 응력 분포를 나타냈다. 5. 최대 신전위와 최대 굴곡위의 비교에서는 수핵 존재시 최대 신전위보다 최대 굴곡위에서 응력 분포가 전후방 모두 2차 정도 감소되고 수핵이 없는 경우는 최대 신전위가 굴곡위보다 응력이 전후방 0.5차 정도 감소되었다. To observe the change in the status of stresses according to three different postural angulation of an intervertebral disc with or without nucleus pulposus, 6 specimens of a 3-dimensional photoelastic model of the spine were made of epoxy. The nucleus pulposus portion was replaced with silicon in three models, and the three were made without silicon. Through axial application of a vertical compressive load of 8㎏, the peculiar patterns of the isochromatic fringes were observed, Stresses on the intervertebral disc were analyzed according to three different postural angulations of the intervertebral disc with the nucleus pulposus and without the nucleus pulposus. The results of these study are as follow : 1. In an erect neutral posture with the nucleus pulposus, the stress concentration was much increased at the posterior portion rather than at the anterior portion. Also, the high stress was concentrated at the medial and central portion. In an erect neutral posture without the nucleus pulposus, the stress concentration was much increased at the anterior portion rather than at the posterior portion and the stress distribution seemed to be locally concentrated. 2. In a maximal flexed posture, the stress concentration was much increased at the posterior portion rather than at the anterior portion. Comparing the presence of the nucleus pulposus with the absence of the nucleus pulposus, the stress concentration was lower at the anterior portion in the presence of the nucleus pulposus than in the absence of the nucleus pulposus. However, the stress distribution at the posterior portion was nearly same in the two groups. According to the analysis of the stress distribution diagram, as a whole, the stress pattern around the disc was evenly distributed. 3. In a maximal extended posture, the higher concentration of the stress distribution at the anterior and medial portion rather than in the posterior and lateral portion was observed. The stress concentration was higher in the presence of the nucleus pulposus than in the absence of the nucleus pulposus. 4. Comparing the maximal flexed posture with the erect neutral posture, the stress concentration in the flexed posture was much decreased in the posterior portion rather than in the erect neutral posture, and an even distribution of the stress pattern in the flexed posture was observed. 5. In the absence of the nucleus pulposus, at the anterior and posterior portion, the stress concentration in the extended posture was much decreased compared with the flexed posture. In the absence of the nucleus pulposus, at the anterior and posterior portion, the stress concentration in the extended posture was much decreased compared with the flexed posture.

2-자유도를 갖는 이동 로보트의 기구학 모델링

문종우,정용욱,김원규,박종국 慶熙大學校 1994 論文集 Vol.23 No.-

In this paper a systematic method for the kinematic modeling of a wheeled mobile robot is presented. This type of methodology is useful to analyze, design, simulate and control any kind of rolling robots. Using the four-wheeled 2-DOF mobile robot as an example, we then analyze the kinematic modeling and through the dead-reckoning updata algorithm, real-time control of WMR position is possible.

마우스에서 애엽 약침액의 급성독성시험

임종국,김철호,조경희,손윤희,배만종,남경수 경산대학교 생명자원개발연구소 2000 생명자원과 산업 Vol.4 No.-

쑥 양침액의 투여와 관련된 변화를 관찰한 결과, 전 시험기간을 통해 단회투여 후 14일 동안 일반증상, 치사율, 체중변화, 부검소견, 장기중량변화, 혈청생화학적 분석등의 각종 지표에 의한 안전성을 평가했을 때 1× 실험군에서는 대조군에 비해 유의한 변화를 관찰할 수 없었으며 10×쑥약침액 투여 후 관찰된 체중의 감소, 혈정생화학적 수치의 유의한 변화는 과용량의 시험물질에 의한 영향으로 생각된다. 한편, 5×, 10×의 쑥약침액을 투여한 실험군에서 활동력 저하, 호흡수 감소, 졸음 및 무기력등의 임상증상이 관찰되었는데 이는 중추신경계 억압에 의한 증상으로 보고??되어 있다. 또한, 혈액내 혈청을 분리하여 간세포 이상의 지표로 사용하고 있는 GOT, GPT를 측정하였고 혈청 중의 total enzyme을 측정하여 LDH의 활성치를 계산, 이것을 심폐질환, 혈액질환, 간질환의 유무를 알아내는 지표로 사용하였으며 간염, 간경변, 골질환의 유무를 알아내는 지표로 사용하는 ALP-s를 측정하였다. 농도에 따른 쑥 약침액의 영향을 알아본 결과 쑥 약침액을 대조군에 비하여 단회투여시 1×의 농도에서는 대조군에 비해 유의한 차이를 나타내지 않았으나 5×, 10×의 농도의 실험군에서는 상당히 유의한 차이를 나타냄으로써 쑥 약침액의 과용량의 투여는 마우스의 간세포, 골세포, 심폐기관 등에 유해작용을 일으킬수 있음을 알 수 있었다. 본 실험을 통해 1×의 쑥 약침액의 용량은 급성 독성시험 결과 무해한 용량으로 판단되며, 5×이하의 용량군을 세밀히 나누어 검토할 필요가 있다고 판단된다. Acute toxicity of Artemisia Nakai Aqua-acupuncture Solution(ANAS) as studied in ICR mice. Mice were injected inrtapeitoneally with single dose of 1×, 5×, 10× ANAS and toxicological responeses were observed for consecutive 14 days. Mortality, clinical signs, body weight changes, organ weight, and serum chemistry were performed. The mortality and body weight changes of mice treated with 1× and 5× ANAS were not affected during the experimental periods. With the 10? ANAS treatment, dead animals and changes of body weight, organ weight and serum biochemical values were observed during the experimental period. There results suggest that 1× ANAS causes no toxicity that 10× ANAS causes toxicity in acute toxicity test.

구륜이동로보트의 기구학적 보정과 모터 제어기의 가속도 해상도를 고려한 속도 궤적의 설계

문종우,김원규,박종국 慶熙大學校 1998 論文集 Vol.27 No.-

This paper presents the kinematic correction method for wheeled-mobile robots with 2 d.o.f. and a design of the velocity trajectory for wheeled-mobile wheel-weight to correct the radios of both wheels. And we use the curvature angle to correct displacement of wheel base. We show that wheeled-mobile robots can't move along the straight-line perfectly and prove that it is attributed to the acceleration constraint of motor controllers and the velocity trajectory have to get a change of velocity in order that wheeled-mobile robots may converge to the straight line. And we experiment on the wheeled-mobile robots with 2 d.o.f. and discuss results.

MQL 선삭가공시 가공조건의 표면거칠기 영향 분석

이춘만,황영국,정종윤 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

At present, industry and researchers are looking for ways to reduce the use of lubricants because of ecological and economical reasons. Therefore, metal cutting is to move toward dry cutting or semi-dry cutting. This paper presents an investigation into MQL(Minimum Quantity Lubrication) machining with the objective of deriving the optimum cutting conditions for the turning process of SM45C. To reach these goals several finish turning experiments were carried out, varying cutting speed, feed rate and oil quantity, with MQL. The surface roughness results of tests were measured and the effects of cutting conditions were analyzed by the method of Analysis of Variance(ANOVA). From the experimental results and ANOVA, it is found that a better surface roughness can be obtained by decreasing oil quantity and feed rate.