Spheroid-based three-dimensional liver-on-a-chip to investigate hepatocyte-hepatic stellate cell interactions and flow effects.

Lee, Seung-A,No, Da Yoon,Kang, Edward,Ju, Jongil,Kim, Dong-Sik,Lee, Sang-Hoon Royal Society of Chemistry 2013 Lab on a chip Vol.13 No.18

<P>We have developed a three-dimensional (3D) liver-on-a-chip to investigate the interaction of hepatocytes and hepatic stellate cells (HSCs) in which primary 3D hepatocyte spheroids and HSCs are co-cultured without direct cell-cell contact. Here, we show that the 3D liver chip offers substantial advantages for the formation and harvesting of spheroids. The most important feature of this liver chip is that it enables continuous flow of medium to the cells through osmotic pumping, and thus requires only minimal handling and no external power source. We also demonstrate that flow assists the formation and long-term maintenance of spheroids. Additionally, we quantitatively and qualitatively investigated the paracrine effects of HSCs, demonstrating that HSCs assist in the maintenance of hepatocyte spheroids and play an important role in the formation of tight cell-cell contacts, thereby improving liver-specific function. Spheroids derived from co-cultures exhibited improved albumin and urea secretion rates compared to mono-cultured spheroids after 9 days. Immunostaining for cytochrome P450 revealed that the enzymatic activity of spheroids co-cultured for 8 days was greater than that of mono-cultured spheroids. These results indicate that this system has the potential for further development as a unique model for studying cellular interactions or as a tool that can be incorporated into other models aimed at creating hepatic structure and prolonging hepatocyte function in culture.</P>

전남지역 한약자원식물 수집분류 및 이용체계에 관한 연구 II. 백운산의 약용식물 자원

이종일(JongIll Lee) 한국자원식물학회 1988 한국자원식물학회지 Vol.1 No.1

전남지역의 명산중의 하나인 백운산 지역에 분포되어 있는 한약자원 식물을 수집 및 분류하여 약용작물로 재배하기 위한 기초자료로 활용하고자 이 지역의 한약자원 식물의 분포를 조사한 결과는 다음과 같았다. 1. 백운산에 분포되어 잇는 약용자원은 60과 250종으로 분류되었다. 2. 분포수종중 과본류는 161 종 목본류 89종이 분포되어 있었다. 3.과본류는 사삼, 도라지, 쑥, 엉겅퀴, 질경이, 차조기, 쇠무릎, 반하, 하수오, 결명자, 용담초, 맥문동, 하고초, 둥글레, 참마, 칡 등이 많이 분포되어 있었고, 목본류로는 굴피나무, 가래나무, 호두나무, 후피향나무, 모란, 이팝나무, 쥐똥나무, 누리장나무, 고로쇠나무, 비자나무, 삼나모, 때죽나무, 모과나무 등이 한약재료로 많이 사용되는 것들이었다. The plants medicinal resources of Mt. Baegun were investigated 21 times from March 1, 1986 to December 30, 1987. In order to analyze the vegetation of Mt.Baegun area, herb plants structure and distribution. Herb plants of Baegun Mt.consisted of 60 families, 250 species in all, The resourees of important herb drugswere Campanulaceae, Salicaceae, Moraceae, Polygonaceae. Amarantaceae, Plant-aglnaceae, Labiatae, Compositae, Asclepiaclaceae, Leguminosae, Gentianaceae, Liliaceae, lilicaceae, Dioscoreaceae, Caprifollaceae, Ranunculaceae, Lauraceae, LardicaDalaceae, Araliaceae, Solanaceaer Cornaceae, Fagaceae and Rosaeeae. Theherb durgs were eomparatively more than in other mountains in our country.

휴대폰용 임베디드 리눅스 부팅시간 단축기법

이종일(Jongil Lee),남영진(Young Jin Nam),김성률(Sung-Ryul Kim),서대화(Dae-Wha Seo) 한국정보과학회 2006 한국정보과학회 학술발표논문집 Vol.33 No.1

휴대폰에 임베디드 리눅스를 탑재하고자 할 경우 전력소모, 경량화, 빠른 부팅, 실시간, 보안 등과 관련한 추가고려사항이 발생한다. 본 연구에서는 휴대폰용 임베디드 리눅스의 커널 부팅시간을 단축시키기 위한 구체적인 방법을 제시하고 실제적인 적용을 통하여 그 성능을 평가한다. 측정된 데이터를 바탕으로 커널 내부에서 가장 많은 시간을 소요하는 함수들을 찾아내고 확인된 함수들에 대해서 초기화 지연회피, 불필요한 장치 드라이버 제거, 불필요한 커널 메시지 미출력 등의 기법들을 각각 적용한다. 제안된 기법을 모두 적용할 경우에 기존 커널 부팅시간을 50%정도 단축시킬 수 있었다.

트레일러를 장착한 차량의 Natural Sway Response에 관한 연구

이종일(Jongil Lee),오승규(Seungkyu Oh),노지훈(Jihoon Roh),이강원(Kangwon Lee),김영우(Youngwoo Kim),김형수(Hyoungsoo Kim),김인동(Indong Kim),장진희(Jinhee Jang) 한국자동차공학회 2009 한국자동차공학회 부문종합 학술대회 Vol.2009 No.4

In this paper, dynamics and stability of vehicle in the yaw plane are examined through 3-DOF vehicle model using standard methodology SAE J2664. This test procedure is proposed evaluation method of natural sway response of a particular trailer. The coupling between vehicle and trailer as two pivoted rigid bodies has been investigated, in view of concerns that the coupling strength varies as vehicle-trailer parameters changing. The changed dynamic characteristics are affected by rotation about the yaw axes and transitions in the lateral direction. Due to the natural sway response of trailer, dynamic characteristics of the vehicle-trailer show unique responses when the impulse steer is applied in the yaw plane motion. In this research, the simple 3-DOF model is proposed to identify the characteristics of the natural sway response. The simulation results show the response of vehicle-trailer based on various trailer’s parameters. As a result, the mathematical model of 3DOF model is proposed and evaluated through J2664. Based on the results of this paper, we could propose a basis model of vehicle-trailer estimator for further research.

TPMS기반의 ESC 제어전략 개발에 관한 연구

이종일(Jongil Lee),김형수(Hyoungsoo Kim),오승규(Seungkyu Oh),이강원(Kangwon Lee),김인동(Indong Kim),구형찬(Hyoungchan Koo) 한국자동차공학회 2010 한국자동차공학회 학술대회 및 전시회 Vol.2010 No.11

TPMS(Tire Pressure Monitoring System) comprise valve stem mounted wheel units for pressure measurement system. From FMVSS138 application, the most vehicles required to put TPMS as standard system. In this paper, we propose new ESC(Electric Stability Control) control strategy with TPMS application. Due to lack of tire pressure, the lateral tire stiffness is decreased. For better ESC performance, the compensation algorithm is required. In this paper, the 7-DOF vehicle model is representing to evaluate the vehicle characteristics, and the yaw moment controller is implemented. The stability control is proposed to integrate with TPMS and compensation algorithm. The result shows the response of vehicle with proposed the algorithm and studied the vehicle stability improvement with proposed control strategy. As conclusion, the stability control with 7-DOF model shows improved performance ESC through TPMS application.

UCC성능평가용 HIL Simulator 차량모델의 파라미터 유효성 평가

이종일(Jongil Lee),장진호(Jinhee Jang),김형수(Hyungsoo Kim) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

전기자동차의 회생 제동량 정량적 평가를 위한 회생제동 지수 개발

이종일(Jongil Lee) 한국자동차공학회 2019 한국자동차공학회 학술대회 및 전시회 Vol.2019 No.11

차량 안정성 향상을 위한 다채널 브레이크 제어에 관한 연구

이종일(Jongil Lee),김형수(Hyoungsoo Kim),공원재(Wonjae Kong) 한국자동차공학회 2013 한국자동차공학회 부문종합 학술대회 Vol.2013 No.5

Electronic Stability Control (ESC) system enforced to standard equipment for all passenger vehicle and less than 4500kgf through KMVSS & ECE R13H regulation. The original ESC system is proposed to control vehicle yaw moment when the driver met evasive driving situation such as emergency condition. Previous studies1) are considered about various method of direct yaw moment (DYC) control to reduce vehicle’s yaw moment. In this study, new control methodology is proposed to enhance vehicle stability using multiple corner braking control through optimizing longitudinal deceleration. This paper proposes control algorithm to distribute brake forces not only front axle for control-ability but also rear axle to improve stability. To optimize control-ability and stability of vehicle, optimized brake for distribution is suggested based upon driver intent maneuver situation using simplified vehicle model. Through vehicle model, the proposed algorithm estimate longitudinal deceleration and lateral deceleration to track optimal driving path condition. Proposed algorithm is evaluated through commercial software MSC.CarSim to verify algorithm performance and evaluated regulation test procedure, sine with dwell test. This regulation test procedure shows quantified value of controller performance comparing the original yaw moment control and proposed algorithm.

RGO 와 Ni(OH)2-VS2 나노복합체의 시너지효과를 기반으로 VARTM 을 이용한 고성능 고체상태 비대칭 슈퍼커패시터의 개발

이종일(Jongil Lee),정창윤(Changyoon Jeong) 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.6

A Study on Strategy for Parallel Import Warranty Policy through Unauthorized Distribution Channels

Pyoungsoo Lee(이평수),JongIl Park(박종일),SungHee Lee(이성희) 중앙대학교 한국전자무역연구소 2018 전자무역연구 Vol.16 No.2

연구목적: 본 연구의 목적은 사례분석을 통해 병행수입과 관련된 정식수입업체의 보증정책전략을 확인하고 그 효과를 분석하는데 있다. 또한 병행수입과 정식수입간의 갈등을 조율할 수 있는 정부정책의 필요성을 확인한다. 논문구성/논리: 본고의 구성은 다음과 같다. 먼저 제 2장에서 병행수입의 개요와 병행수입에 대한 정식수입업체의 보증정책에 대해 개관하며, 제 3장에서는 우리나라 오토바이 시장과 병행수입에 대한 Honda Korea의 보증정책 사례를 분석한다. 제 4장에서는 병행수입에 대한 정책적인 측면을 진단하고 특히 금융지원과 보증정책에 대해 구체적으로 논의한다. 마지막으로 5장에서는 본 연구의 내용을 요약 정리한다. 결과: 본 연구결과, 병행수입업체에 비해 가격경쟁력이 열위인 정식수입업체가 구매를 유인하기 위한 전략은 차별적인 보증정책임을 확인하였다. 이와 관련하여 병행수입품에 대한 정식수입업체의 보증정책을 무차별보증, 유상보증, 보증거부의 세 가지로 분류하고 Honda Korea의 사례를 통해 유상보증정책에서 보증거부정책으로의 변화가 제품전략변화와 맞물려 높은 시장점유율을 확보할 수 있었음을 확인하였다. 또한 정식 수입과 병행수입, 두 가지 유통채널의 갈등을 조율할 수 있는 명확한 정부정책의 필요성을 확인하였다. 독창성/가치: 본 연구는 통계자료를 기반으로 한 특정기업에 대한 사례분석을 통해 표면적으로 나타나지 않은 병행수입과 보증정책의 영향에 대해 확인한 논문으로 의의가 있으며, 향후 병행수입에 대한 정부 정책수립에 있어 시사점을 제공할 수 있다. Purpose: This paper addresses the warranty policies of authorized distribution channels in order to cope with unauthorized channels. In addition, the role of the government, in order to tone down the channel conflicts and improve consumers’ rights, is discussed. The motorcycle market, focusing on Honda Korea’s warranty policy, is demonstrated for the understanding of readers. Composition/Logic: The paper is organized as follows. First, the present condition of parallel imports and warranty policies of authorized channels are described in Section 2. Section 3 deals with the motorcycle market in Korea overall and analyzes a case for warranty policy under parallel imports focusing on Honda Korea. Section 4 presents the government’s acts for parallel imports and discusses two aspects regarding financial support and warranty policies. Finally, the conclusion is summarized in the last section. Findings: The results show that a discriminative warranty strategy acted upon by authorized channels which are less competitive than a parallel importer is the effective way to attract buyers. In this regard, this study categorizes the authorized channels warranty policies for parallel imports as a universal warranty, after sales service at a cost, and denial of service. In the case of Honda Korea, changing warranty policy combined with product strategy was able to secure a high market share. We also identified the necessity of clear government policies that can coordinate both, the authorized channels and parallel imports. Originality/Value: This study is meaningful as it confirms the effects of parallel import and warranty policies that have not been seen through the case analysis of a specific company based on statistical data. In addition, this study explains implications for the establishment of government policies on parallel imports in the future.