난포기 및 황체기에 있어서 돼지 난관협부 평활근의 자율적 운동성에 대한 Estradiol-l7$\beta$및 Progesterone의 영향

이민기,손동수,이영락,남정우,김주헌,최상용,Lee Min-Gi,Son Dong-Soo,Lee Yeong-Lak,Nam Jeong-Woo,Kim Joo-Heon,Choe Sang-Yong 한국임상수의학회 1991 한국임상수의학회지 Vol.8 No.2

The effects of estradiol-17$\beta$ and progesterone on the spontaneous motility of pig oviductal isthmic smooth muscle were investigated. The motility of the Isolated smooth muscle was recorded by using physiological recording system. The results were summarized as follows; 1. The amplitude and frequency of spontaneous motility in pig isthmic smooth muscle were 0.251$\pm$0.023 g and 15.380$\pm$0.935/min in follicular stage, and 0.201$\pm$0.027g and 14.520$\pm$1.382/min in luteal stage. 2. The spontaneous motility of pig isthmic smooth muscle was excited by estradiol-17$\beta$ but was not by progesterone in follicular and luteal stage.

모션캡처 기술 동향

이민기,박성규,박근표,양선우,이범렬,Lee, Min-Gi,Park, Seong-Gyu,Park, Geun-Pyo,Yang, Seon-U,Lee, Beom-Ryeol 한국전자통신연구원 2007 전자통신동향분석 Vol.22 No.4

1990년부터 디지털콘텐츠 제작에 사용되고 있는 모션캡처 기술은 제작비 절감, 콘텐츠의 리얼리티(reality) 향상이라는 장점으로 인해 지속적으로 활용되어 왔다. 최근 디지털콘텐츠가 고품질화 함에 따라 리얼리티의 중요도가 매우 커졌으며, 이로 인해 디지털액터를 리얼하게 움직이기 위한 모션캡처 기술의 활용이 지속적으로 증가하고 있다. 본 고에서는 모션캡처를 데이터 추출 방식에 따라 분류하고, 각각의 장단점에 대해 설명한다. 또한 산업계를 중심으로 개발되고 있는 상용화 기술 동향에 대해 기술하고, 향후 발전 방향을 제시한다.

로보트를 이용한 프로펠러 블레이드 연삭작업의 자동화 시스템 개발

이민기,최병오,Lee, Min-Gi,Choe, Byeong-O 재료연구소 1994 機械와 材料 Vol.6 No.4

G.729 코덱의 패킷 손실 영향 모델을 이용한 비 침입적 음질 예측 기법

이민기,강홍구,Lee, Min-Ki,Kang, Hong-Goo 한국음향학회 2013 韓國音響學會誌 Vol.32 No.2

본 논문은 패킷 손실의 영향을 이용한 비 침입적 음질 평가 방법을 제안한다. 패킷 손실은 패킷 기반의 통신 시스템에서 음질을 저하시키는 주된 요소이며 그 영향은 코덱에 내장된 패킷 손실 은닉 알고리듬에 의해 결정된다. 패킷 손실 영향을 반영한 음질평가 시스템을 위해 VoIP 에서 협대역 코덱으로 사용되는 코덱 중 하나인 G.729를 선택하였으며, 음성 특징에 따른 패킷 손실 영향을 구분하기 위해서 G.729 코덱의 음성 파라미터를 이용한 한 음성 특성 분류기를 설계하였다. 이후, 각각의 패킷 특성에 따른 음질 저하의 정도를 수치화하기 위해 원 PESQ-LQ점수와 상관계수를 최대화하는 음질 저하 가중치를 반복적으로 구하였으며, 최종 음질 저하는 가중합으로 구하였다. 그 결과 제안한 모델과 PESQ-LQ의 상관계수는 칩입 모델 에서는 0.8950를, 비 침입 모델 에서는 0.8911의 결과를 나타내었다. This paper proposes a non-intrusive speech quality estimation method considering the effects of packet loss to perceptual quality. Packet loss is a major reason of quality degradation in a packet based speech communications network, whose effects are different according to the input speech characteristics or the performance of the embedded packet loss concealment (PLC) algorithm. For the quality estimation system that involves packet loss effects, we first observe the packet loss of G.729 codec which is one of narrowband codec in VoIP system. In order to quantify the lost packet affects, we design a classification algorithm only using speech parameters of G.729 decoder. Then, the degradation values of each class are iteratively selected that maximizes the correlation with the degradation PESQ-LQ scores, and total quality degradation is modeled by the weighted sum. From analyzing the correlation measures, we obtained correlation values of 0.8950 for the intrusive model and 0.8911 for the non-intrusive method.

2단 평행기구 로봇 암의 실시간 순방향 기구학 해석

이민기,박근우,Lee, Min-Ki,Park, Kun-Woo 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.1

The determination of the direct kinematics of the parallel mechanism is a difficult problem but has to be solved for any practical use. This paper presents the efficient formulation of the direct kinematics for double parallel robot arm. The robot arm consists of two parallel mechanism, which generate positional and orientational motions, respectively. These motions are decoupled by a passive central axis which is composed of four revolute joints and one prismatic joint. For a set of given lengths of linear actuators, the direct kinematics will find the joint displacements of th central axis from geometric constraints in each parallel mechanism. Then the joint displacements will be converted into the position and the orientation of the end effector of the robot arm. The proposed formulation is decoupled and compacted so that it will be implemented as a real-time direct kinematics. With the proposed formulation, we analyze the motion of the double parallel robot and show its characteristics. Specially, we investigate the workspace in terms of positional space as well as orientational space.

병렬기구형 공작기졔의 기구학적 보정에 관한 연구

이민기,김태성,박근우,Lee, Min-Ki,Kim, Tae-Sung,Park, Kun-Woo 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.11

This research develops a low-cost and high accuracy kinematic calibration method based on the following principles: 1) the platform locations are accurately measured by a constrained movement to inspect a calibration target; 2) the constrained movement is chosen to guarantee the parameter observability; 3) the mechanical fixture to constrain the movement and the sensor to check the constrained movement are implemented by low-cost and high-accuracy devices; 4) the calibration is easily done at an industrial environment. The kinematic parameters calibrated with respect to a single plane aren't influenced due to the misalignment of the plane. A parameter observability is successfully obtained even through one planar constraint, which guarantees that all kinematic parameters are estimated by minimizing the cost function.

정상 성인 무증상 흡연자 , 당뇨병 환자에서 99mTc-DTPA 폐제거율의 측정

김인주,김성장,김용기,김윤성,이민기,박순규 ( In Ju Kim,Seong Jang Kim,Yong Ki Kim,Yun Seong Kim,Min Ki Lee,Soon Kew Park ) 대한핵의학회 1998 핵의학 분자영상 Vol.32 No.3

Purpose: We measured pulmonary epithelial permeability by Tc-DTPA radioaerosol clearance in patients with diabetes and correlated with the presence of microangiopathy to understand the pathophysiology of pulmonary microangiopathy and evaluate Tc-DTPA radioaerosol clearance as a diagnostic test to assess pulmonary microangiopathy. Materials and Methods: We performed ' Tc-DTPA radioaerosol scan in 10 normal subjects, 10 asym-ptomatic smokers, 20 diabetic patients without history of smoking (10 with microangiopathy, 10 without microangiopathy). Tc-DTPA clearance half-time (T1/2) was calculated, then compared with the result of chest radiography and pulmonary function test. Results: Chest radiography and pulmonary function test were normal in all subjects. There were no significant difference of clinical or laboratory characteristics between these groups except age. The diabetic patients with micraangiopathy were significantly older (p<0.05). The T1/2of normal subjects and asyrnptomatic smokers were significantly different (65.2+23.7min vs 39.6+9.8min, p<0.05). For diabetic patients with microangiopathy, the T, was 90 5+46.5min and significantly delayed when compared with those of normals and asymptomatic smokers (p<0.05). However, the T1/2of diabetic patients without microangiopathy, 70.0+12.7 min, was not significantly different from those of normals or asyrnptomatic smokers (p>0.05). No significant correlation was found between the T1/2and spirometric parameters including DLcc>, FVC, FEV>, FEV(/FVC (%) and FEF)5-75g in all subjects, and between the T1/2 and duration of diabetes in diabetic patients. Conclusion: Eventhough the influence of age cant be excluded, delayed Tc-DTPA clearance half-time (T1/2)in diabetic patients with microangiopathy indicates decreased pulmonary cspillary permeability as one of the pathophysiologic results of pulmonary microangiopaththy. Further studies are needed in larger number of age matched control and diabetic patients to evaluate the diagnostic efficacy. (Korean J Nucl Med 1998;32:266-75)

앵글 전단연결재의 강도 및 성능 평가

이민기(Lee, Min-Ki),신경재(Shin, Kyung-Jae),이준섭(Lee, Jun-Seop),김대근(Kim Dae-Geun),장예진(Jang Ye-Jin) 한국강구조학회 2019 한국강구조학회 학술대회 발표집 Vol.30 No.1

고온고압 처리에 따른 인진쑥(Artemisia capillaris Thunberg)과 쑥갓(Chrysanthemum coronarium L.) 내 Caffeoylquinic Acid 유도체의 변화

이민기 ( Min-ki Lee ),김헌웅 ( Heon-woong Kim ),이선혜 ( Seon-hye Lee ),게릴라아사메누 ( Gelila Asamenew ),이수지 ( Suji Lee ),최용민 ( Yongmin Choi ),박진주 ( Jin Ju Park ),이상훈 ( Sang-hoon Lee ),김정봉 ( Jung-bong Kim ) 한국환경농학회 2019 한국환경농학회 학술대회집 Vol.2019 No.-

Capillary wormwood (Artemisia capillaris Thunberg) and crown daisy (Chrysanthemum coronarium L.) belonging to Family Asteraceae have been regarded as traditional medicinal herbs for preventive effects against chronic diseases including vascular disease, diabetes mellitus, and obesity. These plants are known for major resource of diverse caffeoylquinic acid (CQA) derivatives and flavonoid glycosides. Thus, objective of this study was to observe effects on high thermal and pressure processing to their CQA derivatives from capillary wormwood and crown daisy. A total of twenty-six hydroxycinnamoylquinic acid (HCQA) derivatives including p-coumaroylquinic acids (21), CQAs (3), and feruloylquinic acids (2) were separated and identified using UPLC-DAD-QToF/MS. Among them, a total twelve of HCQA derivatives was newly reported. Capillary wormwood and crown daisy were presented great majority of 5-O-caffeoylquinic acid (chlorogenic acid) and 3,5-di-O-caffeoylquinic acid (isochlorogenic acid A). In addition, 3,5-di-O-caffeoyl-4-O-succinylquinic acid was predominant compound in crown daisy. The total contents of HCQA derivatives were tended to decrease slightly during high thermal and pressure processing. Especially, the CQA derivatives which were esterified at 5- position of quinic acid moiety including chlorogenic acid and isochlorogenic acid A were tended to convert 3- and 4- position of CQA derivatives during processing. Therefore, proper high thermal and pressure processing is possible to enhance active ingredients. Furthermore, it can give valuable information for future research of functional foods and drugs.

생산라인용 자동차 변속기용 헬리컬 기어 검사 장치에 관한 연구

이민기(Lee Min-Ki),이응석(Lee Eung-Suk),김기남(Kim Ki-Nam),김광중(Kim Kwang-Jung) 대한기계학회 2010 大韓機械學會論文集A Vol.34 No.2

본 논문은 자동차 변속기의 헬리컬기어 검사 장치에 대한 것이다. 기어 프로파일 전용 검사설비는 시간이 많이 소요되므로 생산라인용으로 적합하지 못하다. 본 논문에서 사용된 마스트기어를 이용하여 생산된 기어와 비교하여 방법은 보다 경제적이며 효율적이다. 본 논문에 사용된 3가지 기어검사 파라미터는 nick, 흔들림(run-out) 및 PCD (pitch circle diameter) 등이다. 기어검사장치의 측정정밀도에 영향을 미치는 요소들에 대해서도 또한 언급되었다. 이 장치는 현재 국내에서 전량 수입되는 기어 생산라인용 설비에 실제적으로 사용될 것이다. This paper presents a study on the helical gear inspection system for application to vehicle transmission gear manufacturing lines. The special gear profile inspection system is not suitable for manufacturing lines due to the measuring time. The master gear method, which was used in this study and compared with the machined gear in the line, is more efficient and economical. In this paper, three helical gear inspection parameters were of concern: nick, run-out, and PCD (pitch circle diameter) error. To evaluate its influence on the accuracy, the gear measuring system was also studied. This system can be useful in practical vehicle transmission gear manufacturing lines, where imported equipment is currently being used.