Modeling and Controller Design of a Community Microgrid

Lu, Jian North Carolina State University ProQuest Dissertat 2018 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Microgrids are becoming increasingly popular in recent decades. The benefits of microgrids include accelerating improvement, increasing reliability, helping customers save money, reducing greenhouse gas emission, etc. Distributed energy resource. In this dissertation, four aspects of the modeling and controller design of a communitylevel hybrid microgrid are researched on. (1) A real-time dynamic CHP model for microgrid applications is presented. The CHP model includes three key componen.

Development of Structured Illumination Reflectance Imaging Technique as a New Modality for Enhanced Defect Detection of Apples

Lu, Yuzhen Michigan State University ProQuest Dissertations & 2018 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Computer vision technology coupled with uniform illumination is still unsatisfactory in detecting some defects of apples, e.g., subsurface tissue bruising. Structured illumination (SI) provides an alternative illumination scheme, which is advant. A SIRI platform, capable of acquiring broadband and multispectral images, was constructed by using a digital micro-mirror device based digital light projector. Using sinusoidally-modulated illumination patterns, SIRI acquires phase-shifted patte. Demodulation is a critical step in obtaining DC and AC images, and conventional approaches require a minimum of three phase-shifted pattern images. New demodulation approaches based on spiral phase transform (SPT) and Gram-Schmidt orthonormaliza. Experiments were conducted on detection of subsurface bruising in apples of four varieties by using a multispectral SIRI system, in conjunction with the SPT demodulation approach. The six wavebands between 710 and 810 nm yielded the overall dete. This research has demonstrated the feasibility and potential of SIRI as a new versatile and effective tool for enhancing defect detection of apples. More research, however, is needed to improve the instrumentation and software of SIRI for real-t.

Research on the Impact of Intellectual Property Protection on Firm Innovation Capability under Life Cycle Theory : -The Mediating Effect of Enterprise Innovation Orientation

YU LU 가천대학교 일반대학원 2022 국내박사

Abstract Research on the Impact of Intellectual Property Protection on Firm Innovation Capability under Life Cycle Theory -The Mediating Effect of Enterprise Innovation Orientation Yu Lu Supervised by Prof. Yang Yi Dept. Of Global Business & Entrepreneurship Graduate School of Gachon University Since China has focused on the overall development of high-tech enterprises with the rapidly growth rate in recent years, those of which belong to the important knowledge-intensive industries in China. They not only play the role of integrating technological resources, but also promoting national economic development. Therefore, they have been attached importance and strongly supported by the state. On this regard, this paper further explores the relationship between intellectual property protection level and innovation capability of high-tech enterprises. Combined with the life cycle theory, it studies the impact on performance in different life cycles, and discusses whether the level of intellectual property protection will improve enterprise innovation ability in any life cycle stage, so as to better speed up their progression, enhance the level of national innovation, promote the comprehensive national competitiveness. First of all, with relevant theories and literature review, this paper analyzes the relationship between enterprise life cycle and innovation capability of high-tech enterprises, then puts forward corresponding research hypotheses. Secondly, it takes listed high-tech enterprises as the research object, divides their industry life cycle, and then adopts multiple regression model to conduct regression analysis on enterprise innovation capability from the whole and life cycle aspects respectively. In the regression results, it tests the influence of intellectual property rights on enterprise innovation ability, and tests the influence of different enterprise life cycle on intellectual property rights and enterprise innovation ability. The research finds that firstly, the overall intellectual property protection has an inverted u-shaped relationship with enterprises. Secondly, intellectual property protection has different impacts on enterprise innovation capability in different life cycle stages. With the enhancement of intellectual property protection level, there exists optimal intellectual property strength for enterprises in growth and decline stages, since there is no optimal IP strength in a recession. Thirdly, innovation orientation has a mediating effect between intellectual property protection and enterprise innovation capability. Finally, it summarizes the model regression results, and puts forward the targeted policies and suggestions from the whole sample and samples in different life cycle stages.

Modeling and controller design of a community microgrid

루지안 ProQuest LLC 2018 국내박사

중국디자인 대학의 창의융합 교육연구

LU LU 한세대학교 대학원 2020 국내박사

현재 중국 디자인 교육과정은 기초 디자인과 전문 디자인으로 구성되어있으며, 바우하우스의 교과과정과 비슷하다. 그러나 바우하우스는 발전과정에서 특히 “뉴 바우하우스” 이념에서는 통합 교육을 더욱 강조하였다. 현재 중국은 다양한 소비자와 복잡한 미디어 환경을 빠르게 형성하고 있으며, 산업에 기여하는 전문 디자인 교육은 전면적인 재편성이 필요하다.그러므로 바우하우스의 교육이념을 도입하고 재편성해야 한다. 따라서 본 연구에서는 초기의 바우하우스의 우수한 교육이념을 다학제,융합설계라는 현대 디자인 교육의 환경으로부터 재검토하였다. 본 논문은 분석종합법을 사용하여 중국과 독일의 관련 역사문헌과 중국의 관련 설계대학 교수모델에 대한 연구를 통해 바우하우스의 핵심관념을 정리, 분석, 판정하였는데 이 관념은 역사적으로 중국과의 연원관계 및 이 관념에 대한 중국교육의 계승과 발전이었다. 본 논문은 “예술과 기술의 통합”은 바우하우스의 교수와 실천을 지도하는 핵심관념을 시카고, 바이마, 울름 등 3개 지역에 있는 "뉴 바우하우스"에서 지속되었다고 생각하였다. 바우하우스는 중국에서 두차례의 역사현상을 겪으면서 양자는 한편으로는 사회경제, 전통조물사상과 민간예술관념에부합되는 기초가 존재한다는 것을 보여주었다. 다른 한편으로 중국은 이 기초에서 발전을 가져와 “과학기술, 예술과 인문의 통합”을 형성할수 있었다. 즉 이론적으로 예술과 기술과 과학의 통합, 교육적으로는 학생 전체의 융합 관념을 형성한다는 것이다. 결국 정보사회의 맥동이 중국 문화의 토양에 뿌리를 내리고, 이를 바탕으로 종합교육 차원에서 중국 디자인 교육 시스템에 대한 건의를 제기하여 중국적인 디자인 교육 모델을 구현하였다.

중국 전지(剪纸)공예기법을 이용한 도자조형 연구

Zhang, Lu Lu 홍익대학교 대학원 2020 국내석사

중국 민간공예인 전지공예는 중국의 오랜 역사와 민족의 풍습이 담겨 있다. 전지는 종이에 가위와 칼로 자르기, 오리기, 찢기 등 다양한 방법으로 인물, 화초, 동물, 산수풍경 등을 만드는 공예 기법이다. 대대로 계승되어온 전지문화는 전통을 기초로 한다. 또한 건축, 가구 디자인, 실내 장식, 상품 포장지, 포스터, 애니메이션, 의상 디자인, 메이크업 등 여러 분야에서 응용되고 있다. 이렇듯 여러 예술 분야에서도 전지공예의 특성이 흡수된 것을 볼 수 있다. 따라서 본 연구는 전지공예를 현대 도자기 장식에 응용하는 것을 목적으로 하였고 다음과 같이 총Ⅴ장으로 구성되었다. Ⅱ장에서는 전지공예의 이론적인 배경 및 도자와의 관계에 대해서 서술하였다. 먼저 전지공예의 기본적인 개념과 역사를 전반적으로 정리하였다. 전지는 문양에 따라 인물, 동물, 문자, 건물, 산수 등으로 나뉜다. 그리고 내용에 따라 원시적인 의미, 문화적인 의미, 실용적인 의미로 나눠지고 용도에 따라 장식, 민속신앙, 기초 문양, 디자인으로 구분된다. 또한 색채에 따라 단색과 다양한 채색으로 나뉜다. 단색전지는 표현형식에 따라 음각전지(陰刻剪紙), 양각전지(陽刻剪紙)과 음양각전지(陰陽刻剪纸)등으로 구분 지을 수 있다. 이를 바탕으로 본고에서는 전지공예와 도자기가 결합한 표현기법, 조형적 특성 등을 분석하였다. Ⅲ장에서는 현대 미술 작가 중 전지와 도자기를 결합한 사례가 많지 않은 상황에서 전지 작가 두 명과 전지를 이용하는 도예 작가 두 명을 선택하여 분석하였다. 작가 스위런(施於人), 지에샤오밍(解曉明)의 도자와 전지를 융합한 작품들을 살펴보고 본인의 작품과의 연관성을 서술하였다. 더불어 현대 전지공예 작가 뤼셩종(呂勝中), 치아오샤오광(喬曉光)의 작품들을 알아보았다. 마지막 Ⅳ장에서는 연구자의 작품에 대해 설명하였다. 본인의 작품은 고대 인물과 동물, 현대 건축의 이미지를 소재로 제작하였다. 작품에서 사용하는 종이 백자의 질감이 매끄러워 작품을 더욱 정교하게 만들었다. 또한 흙과 다른 재료를 같이 사용하여 제작하였다.

Profiling of Humoral Immune Responses to Plasmodium vivax Infection for Discovery of Antigenic Candidates : 삼일열말라리아 감염시 체액성 면역 반응을 유도하는 항원성 후보단백질 발굴

Lu, Feng Kangwon National Univ. 2012 국내박사

삼일열원충의 유전체와 전사체의 규명으로 인해 5,000개 이상의 후보 단백질들의 항원을 연구하는 것이 가능하게 되었다. 고효율 단백질 발현 및 스크리닝 시스템이 확립되어 면역원성이 있는 항원단백질을 연구하기 위하여모두 187개의 항원 유전자(202 단편 유전자)를 선정하였고 이를 PCR 증폭하여 In-Fusion 클로닝 방법을 이용하여 클로닝하였고 고효율 발현과 스크리닝을 실시하였다. 모두 152개의 후보 유전자(160개 유전자 단편)를 성공적으로 클로닝하였으며 wheat germ cell-free system을 이용하여 발현되었다. SDS-PAGE와 면역이적법을 실시한 결과, 고효율 단백질 발현시스템에서 목표 유전자의 92.5%(148/160)를 발현하였으며 96.6%(143/148)가 가용성으로 발현되었다. 발현된 단백질의 평균 회수율은 93.3 µg/ml이며 가용성 비율은 67.7% 이였다. 단백질 어레이를 이용해 모두 11명의 삼일열말라리아 환자의 혈청 단백질을 1차 스크리닝한 결과, 총 45개(28.1%, 18/160)의 단백질이 삼일열말라리아 환자 혈청과 높은 반응성을 보였다. 이들 단백질을 이용하여 면역양상 분석하기 위해 22명의 삼일열말라리아 환자와 10명의 건강한 성인의 혈청들을 이용하여 추가로 분석하였다. 그 중 모두 5개의 단백질이 80% 이상, 21개의 단백질이 50-80%, 12개는 30-50% 그리고 7개는 30% 미만의 양성율을 보였다. 본 연구에서 모두 56% 이상의 단백질(대부분 그 기능이 알려지지 않은 단백질들)이 높은 면역원성을 가지고 있으며, 그 중 하나인 PVX_088910을 선정하여 그 특성을 분석하였다. 침입과정에 관련된 분열소체 단백질들은 분열소체 표면의 glycosylphosphatidylinositol(GPI) anchor 또는 apical organelle(microneme, rhoptry, dense granule)에 위치 하며 그 이후에 침입하는 기생충의 표면 및 PVM 구성을 위한 tight junction으로 위치가 옮겨진다. 열대열원충의 백신 후보물질인 GPI-anchored microneme antigen(GAMA)은 분열체내에서 단백질 가수분해로 처리되어, 궁극적으로 분열소체 표면으로부터 분리된다. PfGAMA의 C-말단 단백질은 적혈구 결합 부위를 보유하고 있으며 적혈구막의 수용체에 결합한다. 삼일열원충의 PvGAMA(PfGAMA의 ortholog) 유전자는 PVX_088910(PlasmoDB)에 의해 coding되고 있지만 아직 특성 분석이 되어있지 않아 이번 연구에서 특성을 연구하였다. PvGAMA는 C-말단 소수성 아미노산 서열, 알라닌(A)과 아스파라긴(N) 아미노산의 반복 및 N-말단에 시스테인 잔기가 많이 존재하고 있다. PvGAMA 유전자의 전체와 그 일부분들은 wheat germ cell-free system으로 발현하였고 면역성 및 항혈청을 생산했다. PvGAMA 단백질을 이용한 말라리아 감염자 혈청의 양성율은 47%(45/96)였고 건강한 성인 혈청의 양성율은 5%(5/96)로 매우 낮았다. PvGAMA의 전사 프로파일(transcription profile)은 성숙한 분열체 단계에서 높게 발현하며 형광현미경으로 분석한 결과, 분열체 내의 apical organelle 특이 단백질로 microneme에서 발현되는 것을 확인하였다. 유전자의 다형성을 분석한 결과, tandem repeat를 포함하고 있는 C-말단 부분이 높은 비율의 유전적 변이가 관찰되었다. PvGAMA는 면역반응성을 보였으며 적혈구와의 결합능을 보였다. 삼일열말라리아 적혈구 발육 단계의 새로운 면역-단백체 연구는 장래 말라리아의 백신과 진단의 기준을 제시해 준다. 본 연구에서는 고효율 스크리닝 방법이 삼일열 말라리아의 적혈구 발육 단계에 특이적인 면역-단백체를 연구하기 위해 사용하였으며, 이러한 방법은 삼일열원충 유전체에서 면역 후보 항원을 결정하는데 사용할 수 있다. Completion of the Plasmodium vivax genome and transcriptome offers chances to identify antigens among > 5,000 candidate proteins. Based on the established system for high-throughput expression and screening of proteins, to further identified P. vivax antigens as targets of immunity, a total of 187 genes/ORFs (202 fragments) were selected and used for PCR amplification and In Fusion cloning. Among - them, 152 candidate genes (160 fragments) were successfully cloned and expressed using wheat germ cell-free system. The results of SDS-PAGE and western blot analysis showed that 92.5% (148/160) of the targets were expressed, and 96.6% (143/148) were provided soluble-form by this high-throughput expression system. The average yield of expressed proteins estimated was 93.3 ?g/ml and the solubility rate was 67.7%. The proteins were preliminary screened with 11 vivax malaria patient sera by protein arrays, a total of 45 (28.1%, 18/160) highly reactive P. vivax antigens were identified. These proteins were further screened with sera from 22 vivax malaria patient and 10 healthy individuals to confirm their immue profiling analysis. Overall, 5 genes produced > 80% of positive rates, 21 genes from 50 to 80%, 12 from 30 to 50%, and 7 from < 30%. More than 56% of the highly immunoreactive proteins were hypothetical proteins (unknown proteins), which were firstly described in this study. One of them, PVX_088910 was selected for characterization. The merozoite proteins related with invasion process were located on either merozoite surface as a glycosylphosphatidylinositol (GPI) anchors or apical organelles (microneme, rhoptry and dense granule) and later trans-located onto the surface of the invading parasite and tight junction for PVM formation. The GPI-anchored microneme antigen (GAMA), as a vaccine candidate of P. falciparum, was proteolytically processed within schizonts, ultimately shed from the surface of merozoites. The C-terminal of PfGAMA with erythrocyte-binding region was bound to its receptor on erythrocyte membrane. The ortholog of PfGAMA in P. vivax (PvGAMA) was encoded by gene PVX_088910 (PlasmoDB), however, was not characterized yet and selected in this study. PvGAMA have a predicted C-terminal hydrophobic sequence (as GPI motif), Ala (A) and Asn (N) amino acid repeats and N-terminal Cys-rich region. The full-length and fragments of PvGAMA were expressed by wheat germ cell-free system and produced immune animal serum.The positive rate of PvGAMA protein microarray was 47% (45/96) with 96 vivax malaria patient samples and 5% (5/96) with 96 healthy samples. The transcription profile of GAMA (PlasmoDB) was highly expressed in the late schizont stage. The localization of PvGAMA in schizont stage parasites were analyzed by IFA and confirmed microneme expression as an apical organelle specific protein. The sequence nucleotide polymorphism analysis revealed that the C-terminal fragment, which includes tandem repeat, has high rates of genetic diversity. PvGAMA was shown to be immunoreactive and had cell-mediated immune response. PvGAMA fusion proteins were able to bind to erythrocyte, and can be inhibited by the specific sera. These novel immune-proteomes of the vivax malaria blood stage provide a baseline for further prospective vaccine and diagnosis studies in malaria. In this study, high-throughput screening assays have been applied to investigate blood stage-specific immune-proteomes from vivax malaria. These methods may be used to determine immunodominant candidate antigens from the P. vivax genome.

A performance-oriented multi-loop control of systems with constraints and uncertainties

Lu, Lu Purdue University 2013 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

In many control applications, the controllers need to be designed such that multiple performance requirements, such as good steady-state tracking accuracy and fast transient response speed, should be achieved simultaneously. However, real systems are often subject to various types of disturbances, uncertainties and physical constraints that make the satisfaction of the multiple performance requirements extremely difficult. In this thesis, a performance-oriented multi-loop control theory is developed to solve the problem. In Chapter 1, the difficulties of designing a control law to meet multiple performance requirements under varieties of system constraints and uncertainties are analyzed, and varieties of traditional control strategies are briefly reviewed with their merits and limitations clearly pointed out. In Chapter 2, a simple system described by a chain of integrators with input saturation and disturbance is used as an introductory example to demonstrate the proposed multi-loop control design and its superiority over previous algorithms. The proposed controller consists of two loops. In the inner loop, a nonlinear control law is designed in continuous-time domain to have an arbitrarily good disturbance rejection performance at the steady-state while keeping the tracking errors with respect to on-line replanned trajectory within certain positive invariant set. In the outer loop, a trajectory replanning unit implemented in discrete-time domain is constructed to generate a replanned trajectory that minimizes the converging time of the replanned trajectory to the desired target. It is theoretically shown that the resulting closed-loop system is globally stable and can track any feasible desired trajectory with a guaranteed steady-state tracking accuracy. Comparative simulation results have been obtained for a third-order integrator to verify the superior performance of the proposed controller over existing major methods in terms of the disturbance rejection capability and the overall respond speed of the resulting closed-loop system. In Chapter 3, the proposed approach is extended to a class of general MIMO nonlinear systems with matched uncertainties and constraints. The uncertainties include both unknown parameters and uncertain disturbances. For the constraints, both input saturation and state constraints are considered. The overall control structure still has two loops as in Chapter 2. However, the design of the inner-loop control law combines the Lyapunov design method with adaptive robust control method to deal with more general MIMO coupling dynamics, parametric uncertainties, lumped disturbances and modeling errors simultaneously. In the outer loop, numerical algorithms are proposed to solve the general constrained time-optimal trajectory planning problem online. The proposed algorithm is successfully simulated on a planar two-axis robotic manipulator system. For many physical systems, the uncertainties show up in the dynamic equations that do not directly contain the control input. These uncertainties are often referred to as "unmatched uncertainties". When the system has both unmatched uncertainties and input saturation, the control law design becomes extremely difficult. In Chapter 4, the challenges of controlling such type of systems are discussed first. It is shown that when both control input saturation and unmatched uncertainties are present, arbitrarily good tracking accuracy at steady state becomes unattainable. Then, a two-loop tracking control strategy for a chain of integrator with unmatched disturbances and input saturation is proposed. In particular, how to select the controller gains such that the proposed control theory is valid is discussed in detail. Finally, the above two-loop control strategy and the gain selection procedure are extended to deal with systems with unmatched parametric uncertainties, disturbances, input saturation and state constraints. In chapter 5, the proposed multi-loop control theory is applied to different industrial systems to show its effectiveness in solving real control problems. Four different physical systems are studied. They include 1-DOF linear motor driven stage, 2-DOF linear motor driven gantry, linear motor driven flexible beam and hydraulic manipulator. For each of the four physical systems, the dynamics and the control objectives are different from others. The uniqueness of the control of these systems is fully discussed. Then, different versions of multi-loop control algorithms are proposed to solve the problems. Experimental results are also presented to verify the effectiveness of the proposed algorithms and their superiorities over some of the traditional control strategies.

Bounds on the enstrophy growth rate for solutions of the three-dimensional Navier-Stokes equations

Lu, Lu University of Michigan 2006 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

It is still an open problem whether smooth solutions to the 3D Navier-Stokes equations lose regularity in finite time. But it is known that if the enstrophy ( w 22 ) remains finite, the solution is regular. The growth rate of the enstrophy can be estimated from the Navier-Stokes equations by Sobolev inequalities. In general form, dw 22/dt≤c w2 2a , where c is a constant. In 2D the exponent alpha is 2 and leads to regularity. However, alpha = 3 in 3D, which yields only finite-time regularity of the solutions. In these estimates, incompressibility is not used. We formulate the maximal enstrophy growth rate as a variational problem and include incompressibility as a constraint. The variational problem is solved numerically by a gradient-flow type algorithm. Our results show that alpha = 1.78 for small enstrophies and alpha = 3 as enstrophy gets larger. Thus the Sobolev bounds are actually realizable even with incompressibility constraint.

Novel UV filtering agents originated from lichens and endolichenic fungi

Lu, Zhao The Graduate School Sunchon National University 2016 국내박사

Ultraviolet radiations exist in the sunlight which is harmful for human health. UVB (280-315nm) radiation is considered to be a carcinogen, and UVA (315-400nm) may be the primary cause of sunlight-induced melanoma because of generation of reactive oxygen species (ROS). Nowadays, the use of sunscreencontaining effective UV filtering agentsis the most common UV protective method. However, there are huge demand of novel sunscreenswhich are composed of natural substances without synthetic chemicals and minerals. Lichens are considered a great bio-resource because they produce large numbers of secondary metabolites with many biological activities,such as antioxidant activity, antimicrobial activity, and anticancer activity.Lichen could survival in strong sunlight condition without damage, the reason may be there are some substance existed in lichen thallus can absorb UV radiation for avoiding damage. Therefore it is a high probability to get UV absorption substances from whose habitat is intensive UV radiation regions. In chapter Ⅱ, weinvestigated the lichen species growing on rocks exposed to high intense of sun light in highland of Yunnan and arid area of Xinjiang province, China, for screening UV absorption active substances. Preliminary results showed there were 19 species of lichencrude extracts exhibiting strong absorption activity inUVB region and two crude extractsisolated from lichens: Cetrariopsis wallichianaand Flavocetraria cucullata, which have both UVB and UVA absorption activities.Based on color and Rf value of the spots on TLC plate, combine retention time and UV spectra of substance peak in HPLC results compared with database of lichen substance to match compounds, the UV absorption active lichen substances were identified.Interestingly, the major UV absorption active substances in C.wallichianaand F.cucullatawere same. The lichen substance which possessed UVB absorption activity was identified as usnic acid and another one was regarded as secalonic acid Awhich could absorbs UVA. Antioxidant activities of 21 samples of lichen crude extracts were determined by four in vitroassays. Antioxidant activity of Secalonic acid A was high than that of usnic acid. Remarkably, the cytotoxicity of these two crude extracts of C.wallichiana and F.cucullatawere muchhigher than other lichens against mouse melanoma cell line, B16F1 and B16F10, and normal cell, HaCaT, which was because the high cytotoxic activity of secalonic acid A. The low IC50valuesof secalonic acid A suggested it might be a good anticancer agent against B16F1 and B16F10 cells, unfortunately, it exhibited high cytotoxicity against HaCaT cell. A disadvantage of lichen is that they have not been cultivated under artificial conditions to date. As a result, lichen substances from natural sources are limited and have not been widely utilized in commercial applications. Accordingly, interest in lichen-associated fungi, especially endogenic fungi, has increased. In chapter Ⅲ, we purified (3R)-5-hydroxymellein, which has UVA absorption activity, from the secondary metabolites of an endolichenic fungus (EL000039). The antioxidant properties were then assessed by in vitro tests. The antioxidant activity of (3R)-5-hydroxymellein was high when compared to the recognized antioxidants ascorbic acid (ASA) and butyl hydroxyl anisole (BHA). Moreover, the compound exhibited no cytotoxicity toward the mouse melanoma cell lines, B16F1 and B16F10, or the normal cell line, HaCaT. Furthermore, (3R)-5-hydroxymellein recovered the damage caused by UVB irradiation and inhibited melanin synthesis. Taken together, these results suggest that (3R)-5-hydroxymellein could be a multifunctional potential UV protective agent byin vitrotests. Finally, the PDB medium was optimal for yield of (3R)-5-hydroxymelleinproduced by endolichenic fungusunder the optimal culture conditions which were at 25℃, medium PH 4.5-6.0 and 21 days period. In chapter Ⅳ, 7-hydroxy-2-octenoic acid-ethyl esterhas UVA absorption activity,whichwas purifiedfrom the secondary metabolites of anotherendolichenic fungus (EL000548). The antioxidant properties were performedby in vitrotests. The superoxide anion scavenging activity and inhibition of linoleic acid peroxidation of 7-hydroxy-2-octenoic acid-ethyl esterwas higherthan ASAand BHA. Moreover, the compound exhibited no cytotoxicity toward the mouse melanoma cell lines, B16F1 and B16F10, except forthe normal cell line, HaCaT. 7-hydroxy-2-octenoic acid-ethyl esterrecovered the damage caused by UVB irradiation and inhibited melanin synthesis. In conclusion, 7-hydroxy-2-octenoic acid-ethyl estercould be anothermultifunctional potential UV protective agent byin vitrotests.