Education and political ideology in North Korea : a critical analysis of educational policy, aims, and nationalism

Sung UMI 1990 국내박사

Laser Development for Photo Therapy and Cartilage Reshaping

Sung Ho Lee Graduate School of UNIST 2018 국내석사

I designed laser systems for Laser Cartilage Reshaping (LCR). To flexible usage, I have de-signed a fiber laser system with outputs at 3 wavelengths, 808nm, 1064nm, 1470nm. We used fiber type laser which provide cost, space, flexibility. The main feature of the fiber laser system is that it can be operated tunable and high power –the loss is less than 20%. This laser system is suitable for more portable applications with limited power output. Following recommendation of Health Care Laser System (HCLS) that invisible laser power for medical approach it cannot pro-duce more than 500mW. We already have enough power to adopt at medical approach. We have tested both laser systems by reshaping septal cartilage samples freshly excised from rabbits.

Hug2Go : The Development of Indoor Smart Driving Personal Mobility

Sung-ho Lee Graduate School of UNIST 2019 국내석사

This paper presents an initial study on the acceptance of indoor PMVs through providing design and development of a new PMVs (Personal Mobility Vehicles). Hug2Go is the indoor personal mobility, finding passenger through self-driving and going to place by a new way of steering. The personal mobility vehicles (PMVs) emerged as a new category of transportation device in the early 2000s. PMVs offers several potential benefits to consumers and society. Many researchers focused on performance or acceptability of use. However, most of PMVs regarded as outdoor mobility. Recently, popular PMVs has been moved to sharing service area. We thought it opportunity area for the mobility market. In this research, we suppose a new model of indoor mobility and examine it possible to build on the market through the usability test. First, we discovered the context of indoor mobility with existing PMVs driving. Through the observation, we found meaningful insights. Second, we designed and developed indoor PMVs. Third, we conducted a usability evaluation with fifteen participants by using Hug2Go. Experimental results with fifteen participants regarding the acceptance of indoor PMVs validated the proposed latent needs. Finally, we discussed findings and opportunities for improvements. The purpose of this study and the development of PMVs is to provide a comprehensive background for initial research of indoor PMVs.

Understanding Design Process from a Perspective of Framing: Exploring the Concept of Frames for Designing

Sung, Hye Rin Hongik University 2017 국내석사

The journey of progressing this study was not possible without all my bright friends and incredible professors at IDAS, Hongik University. Though the journey rather brought a seemed endless cycle of agony-frustration-eureka-enthusiasm, at the end of every day I could be full of excitement for the following steps because of these people. Thank you. My supervising professor Dr. Ken Nah, who has been always inspiring with his insights, is the definite first person I would like to acknowledge. I could keep on track while I have been consistently shifting my frames, thanks to his interest and keen advices. I owe Dr. Junhong Park an enormous gratitude for all those discussions and guidance. This journey has been startlingly fun because of his serious knowledge with wrong humour. And my indescribably beautiful friend Seoyoung Kim, who is always there inspiring and considerate, has kept me in eagerness by sharing unexpected perspectives throughout the course of this research. I feel that it is not enough to express my gratefulness and affection in words, but I only dream of the near day when we could unfold our curiosity together for it to be interwoven wonderfully. I would like to acknowledge Soojung Jun and all my fellow researchers at IDTC lab in Hongik University, for them to exchange invaluable feedbacks. And every one of my research mates from IDAS, especially the residents at room #504, gave me a lot of intriguing points of view which helped me to push my study, I appreciate all immensely. Also, I owe the team from Beyond Design Inc. a huge gratitude for such great inspirations and insights, particularly, Michael Prince for his encouragement and support. And my outstandingly thoughtful and explorative friend Holly Prouty, I would love to thank her for continuously inspiring my mindset and being supportive and attentive from another continent regardless of the distance. Finally, I owe the biggest thankfulness to my adorable family, especially my parents, I would not have come this far without their endless love and support. Seoul, July 2017 Hyerin Sung p.8.oft-Systmes guide to creativity, problem-solving and the process of reaching goals, challenging situations and arrive at satAbstract Design, as a problem-solving process, has been recognised to be thoroughly human-centred. Since the initial move aimed for a major shift from design artefacts to people, the discipline has been progressing forward by developing diverse approaches and methodologies. On the other hand, it has been discussed that the increasing complexity in our world and society is an unprecedented case. Regarding these matters, this study began with two prime questions: 1) when design claims to be the appropriate discipline for human-centred problem solving, why so? 2) how can designers enhance fundamental understanding on people, in response to the slogan ‘designing for people’? Hence, this study aimed to find opportunities for improvement in design in terms of understanding people and dealing with various perspectives, by exploring the concept of frames which is known to be fundamentally related to how we perceive the world differently. The study was implemented in two directions: reviewing literature on both design and frames to extract the essentials for synthesis and analysing a case study to understand design process from a perspective of framing. As a result, design process was reinterpreted with a scope of designers’ framing actions in handling various perspectives and a guidebook was designed to inform designers on useful aspects about the notion of frames. 문제해결 프로세스로서의 디자인은 지금껏, 사람에 초점을 맞춘다는 점에서 큰 관심을 받아왔다. 디자인 인공물 자체에 맞춰져 있던 초점을 디자인을 사용하는 사람으로 이동시키기 위한 시도와 움직임 이래, 디자인 학문은 다양한 접근법과 방법론들을 전개하며 발전해왔다. 한 편으론, 전례 없이 빠르게 복잡해지고 있는 사회에 대한 이슈가 대두되고 있다. 이러한 사항들을 토대로, 본 연구는 두 가지 근본적인 질문에서 출발하였다. 1) 디자인 분야가 사람 중심의 문제해결에 적합한 방법으로 각광받고 있는데, 어떤 면에서 그러한가? 2) 어떻게 하면 디자이너들이 ‘사람을 위해 디자인 한다’는 슬로건에 대응하여, 사람에 대한 근본적인 이해를 높일 수 있을까? 이러한 배경을 바탕으로 본 연구의 목적은, 개개인이 세상을 각기 다른 시각으로 보게 되는 현상에 밀접한 관계가 있는 ‘프레임’이라는 개념의 탐구를 통하여, 사람에 대한 이해와 다양한 시각들을 다뤄야하는 디자인 분야의 발전 방향과 기회의 탐색에 있다. 연구의 방향은 두 가지로 나뉘었다. 첫째로는, 디자인과 프레임에 대한 개별적 문헌 연구를 통하여 디자인 분야에 유용할 수 있는 프레임 개념 관련 요소들을 검토하고 종합하는 연구가 진행되었다. 둘째로는, 사례연구 분석을 통하여 디자인 프로세스를 프레임의 관점에서 해석하고 이해하는 방향으로 진행되었다. 본 연구는 결과적으로, 디자이너들이 사람들의 다양한 시각을 다루는 과정에서 행하는 ‘프레이밍’ 활동에 초점을 맞춰 디자인 프로세스를 재해석하였고, 문헌 연구 등을 바탕으로 추출된 ‘프레임’ 관련 유용 개념 및 핵심 사항 등을 디자이너에게 전달하기 위한 안내 소책자를 디자인하였다.

Comparison of Default Mode Network and Thalamocortical Tract with Conscious state in Chronic Patients with Disorders of Consciousness Following Traumatic Brain Injury : A Diffusion Tensor Tractography Study

Jae Hwa, Bae 영남대학교 대학원 2024 국내박사

이 연구에서 우리는 외상성 뇌손상으로 인한 만성 의식장애 환자들을 대상으로 디폴트 모드 네트워크와 시상피질로의 의식 수준과의 관련성을 연구하였다. 총 21명의 만성 의식장애 환자를 대상으로 확산 텐서 트랙토그래피를 사용하여 디폴트 모드 네트워크와 시상피질로의 분획 이방성과 구조 부피를 정량화하였다. 각 환자의 의식 수준은 혼수 회복 지수-개정판 점수로 평가했다. 연구결과, 디폴트 모드 네트워크의 분획 이방성 값과 구조 부피 값은 혼수 회복 지수-개정판 점수와 강한 양의 상관관계를 나타냈다. 반면, 시상피질로의 분획 이방성 값은 혼수 회복 지수-개정판 점수와 상관 관계를 보이지 않았고, 구조 부피 값은 혼수 회복 지수-개정판 점수와 중간 정도의 상관 관계를 보였다. 따라서 디폴트 모드 네트워크와 시상피질로 모두 의식 수준과 상관 관계를 가지지만, 특히 디폴트 모드 네트워크가 의식 수준과 더 큰 상관관계를 가지는 것으로 나타났다. 우리는 그 원인으로 외상성 뇌손상으로 인한 의식장애 환자에서 미만성 축색 손상이 뇌 손상의 기본적인 기전으로 작용하는데, 특히 디폴트 모드 네트워크가 미만성 축색 손상이 영향을 주는 부위 근처에 위치하기 때문일 것임을 가설로 제시한다. 이 연구는 외상성 뇌손상으로 인한 만성 의식장애 환자에서 디폴트 모드 네트워크와 시상피질로가 의식에 미치는 영향에 대해 동시에 비교한 첫번째 연구로, 디폴트 모드 네트워크가 시상피질로보다 의식 수준과 더 강한 연관성을 보인다는 결과를 보여줬다. 이로써 우리는 디폴트 모드 네트워크가 외상성 뇌손상으로 인한 만성 의식장애 환자의 신경 재활에 더 중요한 타깃이 될 수 있음을 밝혔고, 향후 더 많은 대상을 포함하고 다양한 외상성 뇌손상의 손상 기전을 고려한 연구가 필요함을 제안했다.

레이저에 의한 강과 알루미늄 합금의 이종 금속 간 용접에 관한 연구

주성민 조선대학교 대학원 2005 국내박사

Sung-Min, JOO Advisor: Prof. Han-Sur, BANG, Ph.D Development of dissimilar weldments represents one of the major challenge and remarkable interests in modern manufacturing processes due to great demands for high quality and high performance. So this thesis work has been focused on lap joints of thin sheet materials and on the investigation of the feasibility of laser welding of dissimilar metallic materials by welding steel to aluminum. Materials used are commercial cold rolled steel sheets (SPCC of 1mm thickness) and aluminum alloys (A1100 and A5052 of both 1mm and 2mm thickness) sheets. One of the major problems in the dissimilar welding is the amount of intermetallic compound layer generated in the fusion zone. The problem not only depends on the relative conductivity of heat and the melting point of the two constituent materials but also in the heat source. Generally, it is known that by using conventional heat source, welding of dissimilar metallic materials is almost impossible due to difficulties to control the amount of heat input, and thus wide fusion zone and intermetallic compounds are generated. To overcome this problem, in this paper, laser beam is used as a welding heat source and this welding offers many advantages over conventional welding processes namely, due to the small spot diameter of laser beams, and high energy densities are reached locally, which finally results in a significant improvement of joining speed and a reduction of the melt pool diameter, and thus small heat input and less intermetallic compounds occurred. Welding conditions have been fixed according to the variation of heat input, keeping all other parameters constant. The Fe (SPCC) sheet with higher melting temperature is positioned on the top of the Al sheet with an overlap of 20mm. Also, multiple laser bead weldings have been made and the bead-to-bead distance is changed to investigate its influence on joint strength. FEM analysis has also been carried out for this model and the mechanical behaviors during dissimilar welding is clarified. When the heat input is controlled appropriately, sound dissimilar weldments are achieved. The result shows the potential of using a laser beam as the leading laser technology for welding of dissimilar materials. Therefore, further investigations have to be carried out in order to utilize all the possible advantages in industrial applications.

Epigallocatechin-3-gallate (EGCG) enhances TRAIL-induced apoptosis through DR5 upregulation in human colon cancer cells

권오성 Kyung Hee University 2018 국내박사

Though epigallocatechin-3-gallate (EGCG), a major component of green tea, was known to exhibit anti-inflammatory, anti-diabetes, anti-obesity, and antitumor effect, the underlying antitumor molecular mechanism of EGCG was not fully understood. Here the sensitizing effect of EGCG to TRAIL was examined in colon cancers. Combination of EGCG and TRAIL exerted synergistic cytotoxicity in SW480 and HCT116 cells. Also, combination of EGCG and TRAIL increased early and late apoptotic portion, sub G1 accumulation, the number of TUNEL positive cells in SW480 and HCT116 cells. Also, this combination enhanced the cleavages of poly (adenosine diphosphate-ribose) polymerase (PARP), caspase-8 activation compared to TRAIL or EGCG alone in SW480 and HCT116 cells. Of note, cotreatment of EGCG and TRAIL enhanced the expression of death receptor 5 (DR5) at protein and mRNA levels and attenuated anti-apoptotic proteins in SW480 and HCT116 cells. Conversely, depletion of DR5 by siRNA transfection blocked the apoptotic activity of combination of EGCG and TRAIL to increase cytotoxicity, sub-G1 accumulation and PARP cleavages in SW480 and HCT116 cells. Overall, our study suggests that EGCG can be a sensitizer of TRAIL via DR5 mediated apoptosis in colorectal cancer cells.

TDP-43 regulates local membrane trafficking through Golgi outposts in Drosophila neurons

Sung Soon Park DGIST 2019 국내석사

TDP-43 is a Heterogeneous nuclear ribonucleoprotein (HnRNP) whose abnormal accumulation in the cytoplasm is frequently observed in several neurodegenerative diseases such as ALS/FTD-U. Although molecular functions of TDP-43, such as mRNA processing, have been well characterized, its physiological role in neurons remains unclear. In this study, we elucidated the novel role of dTDP-43 in the formation of Golgi outposts in dendrites. We found that nuclear localization of dTDP-43 increased the number of GOPs in Drosophila C4da neurons. Loss-of-function genetic screening of previously characterized co-factors of dTDP-43 nuclear function showed that two pre-mRNA splicing partners, Hrb27C and Hrb98DE, are associated with dTDP-43-induced increase of GOPs. Additional loss-of-function genetic screening of NGS-derived differentially expressed genes (DEGs) in dTDP-43 overexpressed brain further identified several specific Rab GTPases and their interactors as potential effectors of this novel role of dTDP-43. Finally, we found that late endo-lysosomal compartments and plasma membrane supply were also increased following increased GOPs in dendrites of dTDP-43-expressing neurons. Taken together, our results suggest that TDP-43 contributes to the neuronal local membrane trafficking through the regulation of GOPs. 전세계 적으로 의료 및 복지의 발달과 부합하여 인류의 수명은 점차 증가하고 있으며, 인구 의 고령화가 급속도로 진행되고 있다. 그에 따라 노인성 질환인 퇴행성 뇌 질환에 대한 관심이 날로 높아지고 있다. TDP-43 은 루게릭병 및 치매 등 여러가지 퇴행성 뇌 질환 환자에서 빈번 하게 이상이 관찰되는 단백질이다. 정상인의 신경 세포에서 TDP-43 단백질은 세포의 핵에서 대게 위치를 하고 있지만, 환자들 의 경우에는 이러한 TDP-43 단백질이 핵에서부터 빠져나가 세포질에 위치하며 축적되는 현상이 발생한다. 더군다나 앞선 연구들을 통해 신경세포 특이적인 TDP-43 단백질의 이상 발현 유도는 질병 환자들에게서 나타나는 증상을 모방할 수 있는 것으로 밝혀졌다. 이처럼, 뇌 질환과 밀접하 게 관련되어 있고, 신경세포 특이적인 이상이 질병의 증상을 나타낼 수 있는 것으로 보았을 때, TDP-43 단백질은 신경 세포 내에서 특히나 중요한 역할을 담당하는 것으로 볼 수 있을 것이다. 질병에서의 중요성과 부합하여 현재까지 TDP-43 단백질의 분자 수준에서의 기능, 이를테면 mRNA 의 선택적 스플라이싱 조절 또는 DNA 의 전사 조절 등, 에 대해 다양한 연구들이 이루어 졌다. 하지만 상대적으로 TDP-43 단백질이 세포 수준에서 어떤 역할을 통해 신경세포의 장애를 일으키는지에 대해 아직 연구가 많이 부족한 실정이다. 신경세포는 일반 세포들과 달리 축삭돌기 및 수상돌기와 같이 길게 뻗어나간 구조를 가지고 있다. 일전의 연구들은 TDP-43 단백질의 잘못된 발현이 신경세포에서 이러한 축삭 및 수상 돌 기 구조를 심각하게 손상시키는 것으로 보고 했다. 하지만, 신경세포 내에서 TDP-43 단백질의 이상 발현이 어떤 문제를 초래하여 이러한 손상을 일으키는지에 대해서는 아직 연구가 미미하다. 신경세포에는 신경세포체에서부터 멀리 국지적으로 분포하는 특이적인 세포 소기관들이 존재 한다. 이러한 세포 소기관들은 신경세포의 기능, 발달과 유지 등에 매우 핵심적인 역할을 수행한 다. 비교적 최근에는 Golgi outpost (골지 아웃포스트) 라는 신경세포 소기관이 발견됐다. 골지 아웃포스트는 신경세포의 국지적 장소에서 단백질 분류 및 멤브레인 보충 기능 등을 수행한다. 본 논문에서 우리 연구팀은 유전자 조작이 용이한 초파리 모델을 사용하여 다양한 유전자 조작 실험을 통해 TDP-43 단백질이 신경 세포 내에서 어떤 역할을 수행 하는지 연구하였다. 연구 결 과에 따르면, TDP-43 단백질은 핵에서 특이적인 mRNA 들의 선택적 스플라이싱 조절을 통해 신경세포의 구조 및 기능에 매우 중요한 세포 소기관인 골지 아웃포스트의 형성을 조절하고 이를 통해 국지적 멤브레인의 수송을 조절하는 것으로 밝혀졌다. 여러 퇴행성 뇌 질환에서 TDP-43 단 백질이 핵에서 세포질로 나가는 현상을 볼 때, 이러한 TDP-43 단백질의 핵에서의 기능의 부재 가 질병의 증상과 어떻게 연결 되는지 연구하는 것은 앞으로 남은 중요한 과제일 것이다.

Effects of π-stacking on binding affinities between aromatic foldamers and anions

서성범 Graduate School, Yonsei University 2020 국내석사

본 연구에서는 방향족 분자사이에서 작용하는 인력을 일컫는 π-π 쌓임이, 폴다머 내에서 음이온과의 결합력에 줄 수 있는 영향을 알아보고자 하였다. 이를위해 합성된 폴다머는 염소, 질산염 이온과 결합하여 나선형 접힘을 형성하게 되며, 모두 동일하게 4개의 NH와 1개의 CH를 통해서만 음이온과 상호작용하게하였다. 말단에는 π-π 쌓임 상호작용을 할 수 있는 방향족 단위체들을 도입하였고, 이들 단위체는 음이온과는 전혀 상호작용하지 않으며, 아래에 있는 인돌로카바졸 평면위에 쌓이게 된다. 대부분의 올리고머들이 염소 및 질산염 이온과 1:1로 나선형 착물을 형성하는 것은 X-ray 단결정 구조 분석과 1H NMR sepectroscopy를 통해 각각 확인하였다. 이후, 1H NMR sepectroscopy를 통한 적정실험을 진행하여, 올리고머와 음이온 사이의 결합력을 측정하여, π-π 쌓임이 주는 효과를 비교하고자 했다. 그 결과, 쌓임을 이루는 말단의 단위체가 전자적으로 부족하게 될수록, 결합세기가 증가함을 관찰하였다. 이를 통해, 결합에 직접참여하지 않는 π-π 쌓임이 폴다머와 음이온 사이의 결합력에 영향을 줄 수 있음을 확인하였다. 또한, 이 현상은 이미 알려진 양자계산을 통한 이론적 연구를 토대로, 전자가 부족한 방향족 단위체가 쌓이게 되면, 전하이동(charge transfer)과 정전기적 상호작용(electrostatic attraction)에 의해 인돌로카바졸 고리의 π 전자 밀도가 줄어들어 NH 결합이 더 양극화되기 때문이라고 해석하였다. 이는 π-π쌓임 효과에 의해서 수소결합력이 변화할 수 있음을 뜻한다. 이 연구를 통하여, 음이온 결합과는 관계없는 수용체내의 π-π쌓임에 의해서 음이온 결합력이 조절될 수 있음을 보여주었다. 더 나아가서 서로 독립적으로 간주되던 수소결합과 π-π 쌓임이 독립적이 아니라 서로 상호작용 할 수 있다는 가능성을 제시하였다. This study focuses on identifying influence of π-stacking effect on binding affinity between foldamers and anions. To achieve this purpose new, foldamer-based anion receptors that consist of indolocarbazole and pyridine were synthesized. They have identical hydrogen-bonding sites but different stacking units. X-ray single crystal analysis proved that 1:1 receptor / anion complexes adopt helically folded conformations where anions were encapsulated inside the cavities by hydrogen-bonding. Association constants between receptor and anions, chloride and nitrate ions were investigated by NMR spectroscopic titrations. It appears that the association constants are strongly depend on the electronic nature of the aromatic rings stacked on the indolocarbazoles. As the stacked one are more electron-deficient, the binding affinities are stronger. Based on the theoretical study reported by Geerlings, these results might be interpreted as followings. Stacking of electron-deficient aryl plane may reduce the π-electron density of indolocarbazole owing to the charge transfer between the two planes, and therefore, the indolocarbazole NHs becomes more polarized and better hydrogen-bonding donors to increase the hydrogen bonding strengthes.

Synthesis and characterization of layer structured transition metal chalcogenides with 2D metallic transport

Yu, Hosung Sungkyunkwan university 2018 국내박사

1.1 Motivation and representative research works Since transition metal chalcogenide (TMC) have attracted much attention because of their unique physical properties with two dimensional character. There are lots of materials which crystal structure is already reported but their physical properties are not discovered fully. I have mainly focused on synthesis and characterization of materials which can be applicable to find new phenomena. Here I describes two representative research works. One is ternary layered transition metal chalcogenide Ti2PTe2 with 2D metallic transport and the other is enhanced electropositivity of dense metallic cuboid in layer structured transition metal-rich chalcogenide Hf3Te2. 1.2 Ternary layered transition metal chalcogenide Ti2PTe2 with 2D metallic transport Recently transition metal dichalcogenides (TMDs) have attracted stimulated interest in diverse fields of study in physics and materials science because of their unique physical properties and high potential for applications derived by their weak interlayer attraction, allowing exfoliation into atomically thin layers. But most researches have been focused on the binary compounds with TmCh2 composition (Tm: transition metal, Ch: chalocogen element), and the properties of TMCs are confined to the semiconducting field. So it is necessary to study diverse compound TMCs and their physical properties. Based on the synthesis of high quality single crystal Ti2PTe2, we successfully measured the anisotropic resistivity down to 1.8 K, verifying quasi-2D transport in a weakly disordered metallic regime along the in-plane direction. Combining with Hall coefficient and heat capacity measurements, it is confirmed that the electron-electron interaction is dominant in a bipolar electronic feature. From angle-resolved photoemission spectroscopy (ARPES) measurement combined with DFT calculations, the large electron pockets which have a quasi-2D character and a small hole pocket in the first Brillouin zone center are clearly demonstrated. These results strongly support that quasi-2D metallic nature originates from 2D Ti-network that constructs quasi-2D conducting channels in a ternary Ti2PTe2 crystal. 1.3 Quasi-high-pressure effects in transition-metal-rich dichalcogenide, Hf3Te2 Considering monolayer transition metal chalcogenides with MX2 composition, the trigonal prismatic phase 1H and the octahedral prismatic phase 1T are obtainable consisting of three atoms in an intralayer space. In case of transition metal-rich chalcogenide Hf3Te2, there are five atoms in the intralayer and a hafnium cuboid is sandwiched between outer tellurium atoms. Changes of physical properties are expected due to the chemical pressure induced by structural deformation. To sustain transition metal-rich composition, hafnium metals form cuboid which is comparable with bcc phase of hafnium at high pressure which cause changes in physical properties such as exceeding heat capacity over Dulong-Petit limit and reduced work function. Density functional theory calculations verify that the compressed cuboid in Hf3Te2 has a key role resulting from the intrinsic pressure induced s-d transfer in covalent electrons between Hf-Hf bonding. This transition metal-rich dichalcogenide can guide a route to realize a high pressure element under ambient condition and offer an opportunity to explore a new layered two-dimensional material.