Physiochemical and Oxidative Characteristics of Structured Lipids Containing Pinolenic Acid

Xue-Mei Zhu 충남대학교 대학원 2011 국내박사

Chapter I 효소 촉매반응을 통해 트리아실글리세롤 분자의 sn-2위치의 피놀산 함량을 향상 보도에 의하면 5-불포화 폴리메틸렌 차단 지방산 (5-UPIFAs)은 잣기름(PN)중 트리아실글리세롤(TAG)의 sn-1,3 위치에 풍부하다. 피놀산산(Pi)은∆5-UPIFAs로써 PN중에서 14.2%를 차지한다. 또한 Pi는 20% 이상이 TAG의 sn - 1 및 / 또는 sn – 3 위치에 자리잡고 있다. 이 연구에서는 효소의 촉매작용에 의한 PN과 팜 스테아린(PS)의 에스테르화반응을 통해 아실 마이그레이션이 일어나면서 sn-2위치의 Pi의 양을 향상시켰다. 반응 후, sn-2위치의 Pi의 비율은 그가 전제 지방산중에서 차이한 양과 비슷하다. 예를 들면 50:50(PN: PS)의 비율로 에스테르화된 생성물 중에서 동일한 양 (7.2%)의 Pi가 sn - 2 및 sn - 1, 3 위치에서 검출되었다. 하지만 파이토스테롤과 토코페롤은 에스테르화반응을 통해 감소되었다는 것이 발견됐다. Chapter II 잣기름과 팜 스테아린의 에스테로화 반응을 통해 만들어진 스틱 마가린의 산화특성 잣기름(PN)과 팜스테아린(PS) 를 각각 40:60, 30:70의 무게비로 혼합하여 Lipozyme TL IM을 촉매로 배치타입의 반응기에서 반응시키면 원하는 스틱 마가린 스톡 (재구성지질, SL)을 얻을 수 있다. 하지만 interesterification과 deacidefication 과정에서 소량으로 존재하는 biocomponts( i.e. 토코페롤)의 손실이 검출되었기에 지질의 산화도 따라서 나타나게 될 것이다. 그래서 카테킨과 로즈마리를 마가린 스톡에 첨가하여 보존 안정성을 약화시킨다. 인덱스 (OSI), 과산화수소 값 (POV), 산가 (AV), p- 아니시딘 (p-AV), 2 – Thiobarituric acid-reactive substances (TBARS) 값, 그리고 TOTOX 값들을 가속화된 산화조건에서 측정하면 물리적인 혼합과 비해 SLs는 더 쉽게 산화의 영향을 받게 된다고 평가되었다. 원래 물리적 혼합반응의 유도시간은 10시간 넘는데 에스테르화반응 후 0.18시간으로 줄어들었다. 다행히 카테킨(800 ppm) 과 로즈마리(2000ppm)를 첨가함으로써 SLs의 유도시간이 효과적으로 증가되었다. 그 결과 POV, AV, p-AV, and TBARS 값이 모두 카테킨과 로즈마리가 산화속도를 늦추거나 막을 수 있다는 것을 표시했다. 카테친은 로즈마리보다 항산화 능력이 뛰여나고 SL에 항산화제의 첨가는 산화를 방지하는 효율적인 방법중의 하나이다. Chapter III 정해진 비율로 Sn-2위치에 피놀산이 함유된 재구성지질과 그 특성 잣기름(PN)과 팜스테아린(PS)을 80:20, 50:50, 그리고 20:80의 무게비로 혼합하여 효소를 촉매로 하는 에스테르화 반응을 통해 제로 트랜스 지방을 만들었다. 반응 후 만들어진 주요한 트리아실글리세롤들은 POL/PLO/OPL, 그리고 POP/PPO 등이 있다. 토탈 지방산중의 ∆5-불포화 폴리메틸렌 차단 지방산 (∆5-UPIFAs)은 3.39-13.69%의 범위로 존재한다. 그리고 sn-2 위치의 Δ5–UPIFAs가 3.53-15.53 %로써 물리적 혼합을 통해 만들어진 양보다 높다. 물리 화학적 반응을 통해 에스테르화된 생성물(SL)은 서로 다른 융해와 결정화 프로필이 있으며 보다 낮은 SFC와 SMP 수치를 나타났다. PN:PS 50:50으로 만들어진 SL의 SFC 값은 10, 20, 30, 그리고 35°C 에서 각각 26.5, 18.46, 8.32, 그리고 2.29% 인데 이는 다른 참고문헌에서 나타난 소프트 튜브 마가린의 값과 비슷하다. 동시에 PN:PS 50:50으로 만들어진 SL의 SMP 값은 31.0°C 로써 이미 보도된 값의 범위 안에 있다. 그래서 PN:PS 50:50으로 만들어진 SL은 소프트 튜브 마가린으로 평가할 수 있다. 또한 PN:PS 20:80으로 만들어진 SL의 SFC값은 10-40°C 에서 12.07-59.95%로 나타났는데 쇼트닝과 비슷하다. 그러므로 PN과 PS로 만들어진 제로 트랜스 지방은 소프트 마가린과 쇼트닝을 만드는데 적합하다. Chapter IV 피놀산이 함유된 재구성 지질중의 α – 토코페롤, 아스코빌 팔미테이트, 그리고 쿼시틴등이 지질 산화에 의한 영향 이 연구는 SL이 30일간 60°C의 조건에서 보존하면서 α-토코페롤(α-TOH), 아스코빌 팔미테이트(AP), 그리고 쿼시틴(Qu) 등이 지방산 중의 Δ5-UPIFAs를 지질 산화에서 보호하여 효과를 조사했다. 보존시 α-TOH를 200과 500 ppm보다 높은 농도로 추가할 때 지질 산화를 가속화 한다. 한편, AP와 Qu는 각 농도에서 높은 항산화효과를 나타났다. 항산화 평가 중에서 Qu는 500ppm에서 가정 효과적이다. 또한 Δ5-UPIFAs를 함유한 SL에 α-TOH, AP, Qu등 항산화제들을 2가지 또는 3가지를 서로 조합하여 각각 100, 500, 그리고 500 ppm의 농도로 첨가하여 서로의 상호작용을 분석했다. 그 중에서 항산화제 AP:Qu와 α-TOH:AP:Qu의 조합이 다른 조합보다 훨씬 효과적이다. Chapter I Enrichment of pinolenic acid at the sn-2 position of triacylglycerol molecules through lipase-catalyzed reaction Reports have shown that ∆5-unsaturated polymethylene interrupted fatty acids (∆5-UPIFAs) are enriched at sn-1, 3 positions of triacylglycerols (TAG) in pine (Pinus koraiensis) nut oil (PN). As a major ∆5-UPIFA, about 14.2% of pinolenic acid (Pi) was determined in PN, while the percentage of Pi at the sn-1 and/or sn-3 positions in TAG was found more than 20%. In this current study, the enhancement of Pi at the sn-2 position has been achieved by acyl migration during the lipase-catalyzed interesterification between PN and palm stearin (PS). After reaction, the proportion of Pi increased at sn-2 positional fatty acid even is similar to that in total fatty acid, e.g. in the interesterified product of 50:50 (PN:PS), the same amount of Pi (7.2%) present were detected both at the sn-2 and sn-1, 3 positions. However, the reduction of phytosterols and tocopherols are observed in the interesterified products. Chapter II Production and oxidative properties of stick margarine interesterified from pine nut oil and palm stearin Desire stick margarine stocks (structured lipids, SL) were prepared from pine nut oil (PN) and palm stearin (PS) in weight ratio of 40:60 and 30:70 which catalyzed by Lipozyme TL IM in a batch type reactor. However, the lost of minor biocomponts (i.e. tocopherol) were detected during the processes of interesterification and deacidefication, which is susceptible to lipid oxidation. Thus, catechin and rosemary were added into the margarine stocks to attenuate the storage stability. Comparing with the physical blends, SLs are susceptible to be oxidized which was assessed by index (OSI), peroxide value (POV), acid value (AV), p-anisidine (p-AV), 2-Thiobarituric acid-reactive substances (TBARS) value, and TOTOX value under accelerate oxidation conditions. The induction time of physical blends is over than 10 h, but decreased to 0.18 h after interesterification. Fortunately, the induction time of SLs were effectively increased by addition of catechin (800 ppm) and rosemary (2000 ppm). The results of POV, AV, p-AV, and TBARS value show that the both catechin and rosemary could inhibit or slow down the oxidation. Catechin exhibits better antioxidant capability than rosemary. The addition of antioxidants to SL is one of efficient way to prevent oxidation. Chapter III Scaled production and characterization of structured lipids containing pinolenic acid at sn-2 position Zero-trans fat were produced by lipase-catalyzed interesterification from pine nut oil (PN) and palm stearin (PS) at a weight ratio of 80:20, 50:50, and 20:80. After reaction, the major triacylglycerols (TAG) were POL/PLO/OPL and POP/PPO. The ∆5-unsaturated polymethylene interrupted fatty acids (∆5-UPIFAs) in total fatty acid are ranged from 3.39-13.69. And 3.53-15.53% of sn-2 positional ∆5-UPIFAs were incorporated which are higher than that in the physical blends, the physical characteristics of the interesterified products (SL) had different melting and crystallization profiles, and showed lower SFC and SMP. SFC of SL-PN:PS 50:50 at 10, 20, 30 and 35°C was 26.5, 18.46, 8.32, and 2.29%, which is similar to the SFC of the soft tube margarine fat in literatures, Besides, SMP of SL-PN:PS 50:50 is 31.0°C in the reported ranges of SMP. Thus, SL-PN:PS 50:50 will be appreciable for soft (tub) margarine. In addition, SL-PN:PS 20:80 had SFC values of 12.07-59.95% at 10-40°C, which are corresponding to the shortening fat. Thus, this zero-trans fat could be suitable for soft margarine and shortenings were produced from PN and PS. Chapter IV Effects of α-tocopherol, ascorbyl palmitate, and quercetin on lipid oxidation in structured lipid containing pinolenic acid This study also investigated the effect of α-tocopherol (α-TOH), ascorbyl palmitate (AP), and quercetin (Qu) on protection of ∆5-UPIFAs in SL against lipid oxidation during storage for 30 days at 60 °C. α-TOH accelerated lipid oxidation during storage when added a concentration above 200 and 500 ppm. In contrast, AP and Qu present strongly antioxidative effect at each concentration. Among the antioxidants evaluated, Qu was found to be the most effective, at the concentration of 500 ppm. In addition, the interaction between the antioxidants, binary or ternary combinations of α-TOH, AP, and Qu were added to SL containing ∆5-UPIFAs at concentrations of 100, 500, and 500 ppm, respectively. Antioxidants of AP:Qu and α-TOH:AP:Qu were significantly effective than the other combinations.

여태현『 오늘은 누구도 행복하지 않았으면 좋겠단 생각을 했습니다 』의 한중변역

GAO XUE MEI 가천대학교 일반대학원 2021 국내석사

여태현 작가의 산문집 『오늘은 누구도 행복하지 않았으면 좋겠단 생각을 했습니다』는 「가까워지는 줄 알았던 날들이 때론 멀어지기 위한 과정이었단 사실 그땐 몰랐다」, 「어떤 밤에는 이유 없이 외로울 수도 있다고」, 「그렇다면 사랑이라고 되지 말란 법 있겠습니까」 등 총 3장으로 구성되어 있다. 앞의 두 장은 주로 우리가 외로울 수밖에 없는 이유들이 담겨있고, 마지막 장은 그럼에도 불구하고 우리가 외로움을 견딜 수 있게 해주는 이유들을 이야기하고 있다. 본서는 분명 위로에 목적을 둔 산문집이다. 그러나 작가는 독자들을 위로하지 않을 뿐 아니라, 오히려 ‘외로운 것은 이상한 것 아니라는’낯선 관점으로 접근하였다. 여태현 작가는 소설 창작에 종사해보았기에 짧은 산문 속에서도 스토리텔링의 기법을 잘 구사하고 있다. 작가는 옛 연인과의 만남에서 이별 사이의 기억과 감정들을 들려주며, 사랑하는 사람과 이별한 후 그 상실감에서 느끼는 외로움과 그리움을 담담한 언어로 담아내며 공감을 이끌어 내는 한편, 직접적인 위로보다는, 자신의 경험을 이야기로 풀어내며 독자로 하여금 자연스레 위안을 얻도록 해준다. 또한 본서는 외로움에 대한 직접적인 위로 대신, 외로움을 이기는 사뭇 다른 방법을 제시해준다. 사람들은 보통 어려움에 부딪칠 경우 애써 그것을 이겨내려 하지만, 작가는 오히려 그것을 있는 그대로 받아들이라고 강조한다. 우리의 삶에서 자주 마주치는 외로움은 전혀 이상할 것이 없는, 누구나 경험하는 일이기 때문이라는 것이다. 작가는 혼자만의 외로움을 우리 모두의 외로움으로 확대시켜 골고루 나누어 주기에, 외로움이란 혼자만의 고통이 아닌 모두가 지니고 있는 인간 본연의 것임을 깨닫게 해주며 암암리에 위안의 선물을 안겨준다.

Customer efficiency: Concept and its impact on service management

Xue, Mei University of Pennsylvania 2002 해외박사(DDOD)

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

This dissertation investigates the impact of the increasing participation of customers in service delivery processes that has been enabled by the advances in information technology. The concept of Customer Efficiency (CE) is introduced along with a conceptual framework for Customer Efficiency Management (CEM) described in Chapter 2. In Chapter 3, a game-theoretic model is developed in order to study competition among service providers when self-service is an option. The analysis of the equilibria from this model shows that, given average customer efficiency, the proportion of the service task outsourced to the customer is a decisive factor in the resulting competitive equilibria. A large-scale empirical study to investigate the impact of self-service on service delivery costs and customer-firm relationship in retail banking is described in Chapter 4. These results show that self-service through the Internet has a significant migration effect on personal service and, consequently, saves service delivery costs and improves customer efficiency. Contrary to conventional wisdom, we find no evidence that increasing levels of self-service damage customer relationships.

Visual tracking and illumination recovery via sparse representation

Mei, Xue University of Maryland, College Park 2009 해외박사(DDOD)

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

Compressive sensing, or sparse representation, has played a fundamental role in many fields of science. It shows that the signals and images can be reconstructed from far fewer measurements than what is usually considered to be necessary. In this dissertation, we present the results of a study of applying sparse representation to illumination recovery, object tracking, and simultaneous tracking and recognition. Illumination recovery, also known as inverse lighting, is the problem of recovering an illumination distribution in a scene from the appearance of objects located in the scene. It is used for Augmented Reality, where the virtual objects match the existing image and cast convincing shadows on the real scene rendered with the recovered illumination. Shadows in a scene are caused by the occlusion of incoming light, and thus contain information about the lighting of the scene. Although shadows have been used in determining the 3D shape of the object that casts shadows onto the scene, few studies have focused on the illumination information provided by the shadows. In this dissertation, we recover the illumination of a scene from a single image with cast shadows given the geometry of the scene. The images with cast shadows can be quite complex and therefore cannot be well approximated by low-dimensional linear subspaces. However, in this study we show that the set of images produced by a Lambertian scene with cast shadows can be efficiently represented by a sparse set of images generated by directional light sources. We first model an image with cast shadows as composed of a diffusive part (without cast shadows) and a residual part that captures cast shadows. Then, we express the problem in an ℓ1-regularized least squares formulation, with nonnegativity constraints (as light has to be nonnegative at any point in space). Visual tracking, which consistently infers the motion of a desired target in a video sequence, has been an active and fruitful research topic in computer vision for decades. It has many practical applications such as surveillance, human computer interaction, medical imaging and so on. Many challenges to design a robust tracking algorithm come from the enormous unpredictable variations in the target, such as deformations, fast motion, occlusions, background clutter, and lighting changes. To tackle the challenges posed by tracking, we propose a robust visual tracking method by casting tracking as a sparse approximation problem in a particle filter framework. In this framework, occlusion, noise and other challenging issues are addressed seamlessly through a set of trivial templates. Specifically, to find the tracking target at a new frame, each target candidate is sparsely represented in the space spanned by target templates and trivial templates. The sparsity is achieved by solving an ℓ1 -regularized least squares problem. Then the candidate with the smallest projection error is taken as the tracking target. After that, tracking is continued using a Bayesian state inference framework in which a particle filter is used for propagating sample distributions over time. Three additional components further improve the robustness of our approach: (1) a velocity incorporated motion model that helps concentrate the samples on the true target location in the next frame, (2) the nonnegativity constraints that help filter out clutter that is similar to tracked targets in reversed intensity patterns, and (3) a dynamic template update scheme that keeps track of the most representative templates throughout the tracking procedure. We test the proposed approach on many challenging sequences involving heavy occlusions, drastic illumination changes, large scale changes, non-rigid object movement, out-of-plane rotation, and large pose variations. The proposed approach shows excellent performance in comparison with four previously proposed trackers. We also extend the work to simultaneous tracking and recognition in vehicle classification in IR video sequences. We attempt to resolve the uncertainties in tracking and recognition at the same time by introducing a static template set that stores target images in various conditions such as different poses, lighting, and so on. The recognition results at each frame are propagated to produce the final result for the whole video. The tracking result is evaluated at each frame and low confidence in tracking performance initiates a new cycle of tracking and classification. We demonstrate the robustness of the proposed method on vehicle tracking and classification using outdoor IR video sequences. (Abstract shortened by UMI.).

교과서에 나타난 물리용어로 정의된 물리지식 네트워크 분석

Xue Mei, Cui 충북대학교 2012 국내박사

책은 수많은 단어들로 구성된 복잡계(complex system)이다. 책의 한 종류로서의 물리교과서는 물리용어들로 구성된 복잡계이다. 물리교과서는 물리지식을 가르치고 배우는 주요한 자료이므로 물리교과서가 이루고 있는 복잡계의 특성을 이해할 필요가 있다. 본 연구에서는 물리 교과서에서 사용된 개개 물리 용어들의 통계적 특성과 동적 특성을 분석하고, 또한 이러한 특성이 물리 용어 집단 전체의 네트워크 특성에 미치는 영향을 물리교과서와 물리용어 사전에 대한 비교를 통하여 분석하였다. 먼저 개개 물리용어에 대한 통계적 특성 분석으로 빈도수 분포와 쌍 빈도수(co-occurrence) 분포를 조사하였다. 물리 교과서와 물리용어 사전에서 나타나는 물리용어들의 빈도수 분포와 쌍 빈도수 분포는 모두 멱함수 법칙을 따르지만, 물리용어 사전에서 빈도수와 쌍 빈도수 분포도는 물리 교과서에 비해 작은 빈도 쪽으로 편중된다. 물리 교과서에서 물리용어가 나타나는 동적 패턴을 보면 특정 시점에서 용어가 집중적으로 나타나는 버스트(burst) 특성이 있다. 이로 인해 물리용어가 나타나는 시간간격(interval)도 멱함수 특성을 가지게 된다. 이것은 물리용어가 집중되어 나타나는 구간에서는 짧은 시간간격이 많이 생기고, 그렇지 않은 구간에서는 긴 시간간격이 나타나기 때문이다. 반면, 물리용어 사전에서는 물리용어가 나타나는 시간간격의 분포가 지수함수 특성을 나타내고 있었다. 이는 물리용어 사전의 물리용어의 버스트 특성이 물리 교과서보다 약함을 의미한다. 물리용어가 집중되어 나타나는 정도-버스트 정도(burstiness)-를 정량화하는 불균일성(non-uniformity) 척도(measure)를 정의하여 물리용어 사전의 물리용어의 버스트 정도가 물리 교과서보다 낮음을 정량적으로 보여주었다. 물리 교과서와 물리용어 사전이 이루고 있는 네트워크 특성을 분석하기 위해 물리용어 간의 연관성(association)을 나타내는 W값으로 가중치 네트워크(weighted network)를 구축하였고, W값을 규격화하여 얻은 Z값으로 부호 있는 가중치 네트워크(signed weighted network)를 구축하였다. 두 가지 네트워크에서 물리 교과서 네트워크는 모듈성(modularity)이 강하지만 물리용어 사전 네트워크의 모듈성은 아주 약하다는 것을 보여주었다. 즉 물리 교과서에서는 서로 연관된 물리지식들이 집단을 이루고 있지만, 물리용어 사전에서는 그렇지 못하다는 것이다. 버스트 정도와 네트워크 모듈성의 관계에 대한 분석을 통해 계(system)의 버스트 정도가 클수록 계의 네트워크의 모듈성도 강하다는 결론을 정량적으로 보여주었다. 이러한 결과를 토대로 계의 동적 특성인 버스트 정도와 네트워크의 특성인 모듈성이 서로 연관되어 있다고 제안한다. 물리 교과서에서 나타나는 물리용어는 버스트 정도가 높고, 물리 교과서의 물리지식 네트워크의 모듈성은 강하다. 이는 물리 교과서가 물리용어 사전과 비교되는 특성이다. 이러한 특성 때문에 물리 교과서는 주요 학습자료로, 물리용어 사전은 보조 학습자료로 쓰인다고 할 수 있다. The book is a complex system composed of many words. The physics textbook is a complex system comprised of the physical terms. The physics textbook is the main material of teaching and learning physics knowledge. We need to understand the properties of the physics textbooks as a complex system. In this study, we analyzed statistical and dynamical properties of physics terms in the physics textbooks and compared the results with those of a dictionary of physics terms. First, we constructed the frequency distribution and co-occurrence distribution. The frequency distribution and co-occurrence distribution of the physics textbooks and a dictionary of physics all follow the power law. But, the frequency distribution and co-occurrence distribution of the dictionary of physics are biased toward small frequency compared to the physics textbooks. The dynamic pattern of physics term appeared in the physics textbooks has burst property. Therefore, the physics term occurrence interval will follow power law. In the range of frequent appearance of a particular physics term we have a lot of short intervals, while in other ranges we have long intervals. The interval distribution of the dictionary of physics follows exponential function. This means that the burstiness of dictionary of physics is weaker than that of the physics textbooks. We defined non-uniformity to quantify burstiness of physics terms. We quantitatively demonstrated that the burstiness of dictionary of physics is weaker than the physics textbooks. We constructed weighted network with the value W of association between two physics terms. The signed weighted network can also be characterized by the value Z which is obtained from W by normalization. The modularity of the physics textbooks is stronger than the dictionary of physics in weighted network and signed weighted network. In other words, the physics textbooks consist of communities of interrelated physics terms. We quantitatively demonstrated that the stronger burstiness leads to stronger network modularity. Based on these results, we could propose the dynamic burstiness and network modularity are interconnected. The burstiness of physics terms and the modularity of physical knowledge are stronger in the physics textbooks than in the dictionary of physics. Because of these characteristics, we suppose, the physics textbooks are used as a major learning materials and the dictionaries of physics are used as subsidiary learning materials.

Transport in nanoscale devices

Xue, Mei University of California, Los Angeles 2009 해외박사(DDOD)

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

The drive toward further miniaturization of silicon-based electronics has led to renewed efforts to build molecular-scale components. A key step in using individual molecules as active circuit elements is the understanding of charge transport through metal-molecule-metal junctions. In our work, we focus on the two transport mechanisms in nanoscale devices, namely hopping and tunneling transport. The former is studied using polyaniline nanofiber with a about 2microm conduction path; the latter is studied using molecular rotor devices with a mono molecular layer of about 3nm. The major issues involved in the synthesis, device processing, and characterization are discussed. Hopping transport is studied using interfacial synthesized polyaniline nanofibers doped with chloride acid (HCl). The investigation of the temperature dependence of the conductivity suggests that polyaniline nanofibers are more sensitive to temperature than conventionally synthesized ones. The sensitivity dependence of the conductance on the doping concentration was measured, showing a saturation point based on the material property. A three-dimensional conduction hopping model is proposed to explain the experimental results. Tunneling transport is the emphasis of this thesis work since it is the dominant conduction mechanism in the nanoscale regime. Tunneling transport is studied using a molecule rotor device comprised of a monolayer of redox-active ligated copper compounds sandwiched between a gold electrode and a highly-doped P+ Si substrate as our model system because of its interesting optical, mechanical and electrical properties. A self-assembled chemical method of the molecule rotor layer was developed based on the strategy of a surface outward sequential synthesis that ensures the formation of Si-immobilized heteroleptic copper compounds. Both multilayer and monolayer molecular rotor devices were fabricated and the rotation of redox-dependent ligand rotation around the copper metal center was confirmed using optical absorption spectroscopy. The switching effects of both multilayer and monolayer molecular rotor devices were characterized. We focus on the fabricated electrically driven sandwich-type molecular rotor device comprised of a monolayer of transition metal complexes containing redox-active pi-conjugated ligand subunits between a gold electrode and a highly-doped Si substrate. Our calculations predicted operational speeds in the picosecond timescale. Current-voltage spectroscopy curves (I-V) showed a negative differential resistance (NDR) associated with the devices, while reference samples of individual subunits, namely the redox-active pi-conjugated ligands and uncoordinated metal complexes alone, did not. Modeling of transverse molecular current conduction using time-dependent density function theory suggested the source of the observed NDR to be rotation of the ligand around Cu complexes. Optical absorption spectroscopy and the observed temperature dependence of the NDR behavior also support this hypothesis. The basic principle of the switching phenomenon as well as the band diagram is constructed to explain the electron transport behavior during the device operation. This is the first time a rotation-induced NDR effect on a solid support has been observed. To study the scalability of the molecular rotor device, we extend our discussion to electron and ion transport and study their physical scalability. Furthermore, we describe the optimized chip architecture for integrating molecular switches with the conventional CMOS circuits to achieve a CMOL logic system.

역량기반 대학교육과정 개발을 위한 백워드 설계 방안 연구

Kang Xue Mei 경북대학교 대학원 2021 국내석사

The Backward Design for Competency- Based University Curriculum Development This study developed a competency-based university curriculum competency-based college education courses are designed through the analysis of the foreseeable or practical effects of modern society, and students achievements are evaluated according to the practices related to their effects. With the arrival of the knowledge-based era of the fourth industrial revolution in the 21st century, in order to fulfill the new functions and functions, university education has gradually changed from knowledge-based education to competency-based education. In order to adapt to a rapidly changing society, students need to go beyond academic learning and master high-level, comprehensive abilities. The higher education in the world has developed from the modern European universities in the Middle Ages to the present, and the idea of university curriculum, which embodies the specific idea of talent training, has been in the process of continuous development. In the history of curriculum development, due to the different times background, people's political stand and philosophical tendency, led to the different understanding of curriculum value, and thus appeared different pursuit of curriculum value. Whatever education curriculum innovation, in the practice of the higher education, a always been higher educationist height should focus on the core of the problem is that university courses in what is, what kind of knowledge, teach students at the university when dealing with the social development put forward new requirements, often with curriculum as the breakthrough point, in accordance with the requirements of social development and the changing needs of students, the reform of college curriculum structure, To add new functions to meet the new requirements of society, and then achieve the purpose of reforming higher education. Establish a high quality university curriculum system. Competency-based education curriculum provides personal and social adaptability of education curriculum, puts the formation of learners power at the core of education curriculum, and emphasizes default knowledge, embodied knowledge and experiential knowledge. Therefore, competency- based education curriculum has become an alternative education topic. The first step in designing an education program is to identify the educational goals, not the goals on the curriculum. Teaching without a clear goal is a meaningless activity and has only vague evaluation criteria for effectiveness. The goal of any course should be that genuine understanding is more important than mere acquisition of knowledge. There are many college graduates. but almost no excellent college graduates and other social phenomena to accurately understand, universities should analyze the social phenomenon, the construction of students to meet the needs of students and social needs of the goal-oriented education mode plan and the implementation of the curriculum. Therefore, this research aims to design a reverse design scheme for competency-based college education courses. Through a true understanding of the strength elements that college students must acquire, the Whereto model is used to evaluate the strength elements that students must acquire. For the above purposes, Wiggins and McTighe(2007) proposed This paper introduces the characteristics and development of competency-based college education curriculum. On the basis of this analysis, it is concluded that the expected effect of the unit is also an evaluation method. Then to based on the strength of the development of university education courses, cultivate its goal, which is to guide the main body of a true understanding, design good students are required to obtain the power of the elements are organized into six big template to investigate implementation effect, it has been applied in the researchers of course tasks, the written test results, the investigation of student achievement, in-depth interviews, students And classroom observation logs that analyzed the researchers colleagues to understand their performance and insights. The main contents of this study are summarized as follows: Chapter I, describes the necessity and purpose of the research, Research question, research method, research scope and definition. Chapter II, theoretical background. It includes the change of university function and function, the development of competency-based education and education curriculum, the future development trend of competency-based university education curriculum and the theoretical model and methods of research. Chapter III, This study uses Backward design to design the competency-based curriculum of university education and analyzes the development trend of university education curriculum in the future to determine the foundation and direction of the design scheme. It includes the establishment, development, design, evaluation and a series of design schemes of the reverse design model of competency-based curriculum. Chapter IV, the results and discussion. The competency that college students must acquire and the characteristics of the backward schematic design for university curriculum on the basis of competency are described. This study set three research questions. The first research question was “What kind of competency should college students get?” and “How to derive the competency - based university education curriculum after backward design?” The third research question was “What are the goals and results of the curriculum of university education designed by backward design?” In order to answer these research questions, this research is mainly carried out a literature review was conducted. Through literature research, a backward design scheme for the development of a competency-based university education curriculum is designed. The backward design is used to deal with university education curriculum, evaluation, teaching, learning principles, teachers' duties, etc. It provides the means to design the viewpoint of university education curriculum, and puts forward the viewpoint that the blueprint and goal pursued by the university can be successfully realized. It also focuses on understanding sustainability based on the main ideas. What should university teachers focus on to develop and implement instruction? What is the reason for a university education? What is the reason we teach in university education? Through teaching, students are properly trained and taught to understand how to develop real understanding. In addition, competency-based university education courses will provide acceptable evidence, learning experiences, lectures and strategies for successful backward design. Based on the results of this study, the following conclusions can be drawn based on the fact that the reverse design of college education courses in order to promote and increase the learners, deep understanding of education, academic achievement and interest. Stimulate a true understanding of the professional curriculum and parenting curriculum, allowing them enough time to deviate from the knowledge based on content to form their own meaning and understanding. Finally, educators should realize the importance of students needs and social needs through effective changes.

(The) characteristics of CSR engaging firms in Korea

이설매 Graduate School, Yonsei University 2009 국내석사