Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: a comparison to InGaN-based visible flip-chip light-emitting diodes.

Lee, Keon Hwa,Park, Hyun Jung,Kim, Seung Hwan,Asadirad, Mojtaba,Moon, Yong-Tae,Kwak, Joon Seop,Ryou, Jae-Hyun Optical Society of America 2015 Optics express Vol.23 No.16

<P>We study light-extraction efficiency (LEE) of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) using flip-chip (FC) devices with varied thickness in remaining sapphire substrate by experimental output power measurement and computational methods using 3-dimensional finite-difference time-domain (3D-FDTD) and Monte Carlo ray-tracing simulations. Light-output power of DUV-FCLEDs compared at a current of 20 mA increases with thicker sapphire, showing higher LEE for an LED with 250-관m-thick sapphire by ~39% than that with 100-관m-thick sapphire. In contrast, LEEs of visible FCLEDs show only marginal improvement with increasing sapphire thickness, that is, ~6% improvement for an LED with 250-관m-thick sapphire. 3D-FDTD simulation reveals a mechanism of enhanced light extraction with various sidewall roughness and thickness in sapphire substrates. Ray tracing simulation examines the light propagation behavior of DUV-FCLED structures. The enhanced output power and higher LEE strongly depends on the sidewall roughness of the sapphire substrate rather than thickness itself. The thickness starts playing a role only when the sapphire sidewalls become rough. The roughened surface of sapphire sidewall during chip-separation process is critical for TM-polarized photons from AlGaN quantum wells to escape in lateral directions before they are absorbed by p-GaN and Au-metal. Furthermore, the ray tracing results show a reasonably good agreement with the experimental result of the LEE.</P>

An Investigation on the Life of Master Won Guk Lee, the Creator of Chung-Do-Kwan

( Seon Young Jung ),( Jun Ho Lee ),( Seung Woo Shin ),( Chun Hwan Cho ),( Seung Hyun Jang ),( Won Shin ) 경남대학교 기초과학연구소 2014 기초과학지 Vol.31 No.-

The purpose of this study is to review (or, investigate) the life of Won Guk Lee. He is the creator of Chung-Do-Kwan, which is one of the five original Taekwondo kwans. Data was gathered from advanced research, newspapers, documentaries, the Internet, magazines, and journals etc. Thus, we were able to create a sequence of events based on the research data. First, we can say that in Won Guk Lee``s career, he created Chung-Do-Kwan and brought Dangsoodo to Korea. These events have had a significant development on Taekwondo. Second, Taekwondo curriculum, which was published by Won Guk Lee, established the foundation of Taekwondo poomsae, as well as giving us the pure spirit of Korean martial arts.

QS-9000에서의 계측시스템 관리

이승훈,이종환 東義大學校産業技術開發硏究所 1998 産業技術硏究誌 Vol.12 No.-

Measurement plays a significant role in helping any organization improve quality. Therefore an appropriate measurement system analysis should be conducted for the understanding and quantification of the sources of variability present in the measurement process. QS-9000 defines the fundamental quality system expectations of Chrysler, Ford, GM, Truck Manufacturers and other subscribing companies for internal and external suppliers of production and service parts and materials. These automakers are requiring their suppliers to implement the QS-9000 quality system. We review the general guidelines for the measurement system control in QS-9000 and present the statistical basis for the measurement system analysis techniques in this paper.

金井山 林道開設에 따르는 問題点에 관한 硏究

이경재,류창희,김승환,박승범 東亞大學校生命資源科學大學附設 農業資源硏究所 1993 農業生命資援硏究 Vol.2 No.1

Mt. Gum-Jung is a very important mountain of Pusan which is connected to the large branch of Mt. Baek-Du, range including Mt. Baek-Du, Mt. Un-Ju, Mt. Ka-Zi, Chui-Seo and Mt. Gum-Jung. It is also attached to Nak-Dong river linked to Mt. Baek-Yang and Mt. Seung-Hak. Regarding the Korean peninsula as one natural ecosystem, the large branch of Mt. Gum-Jung. Therefore, it is very important to primarily preserve it from ecological point of view. In case of constructing the forest road, the width of the road is 4 meters approximately, but the actual damaged width of the forest which includes the shoulder of both sides of the road, drainage ditches and the areas cutting the lower plants of trees, will be around 20∼28 meters. Since the forest road paved with concrete pavements and the gravel divides the ecosystem of the forests and thus destroys the ecological system, it should be paved with the natural materials, such as soils, herbals and so forth. The forests of Mt. Gum-Jung which have almost been in the 2nd transitional stage, have some areas showing active ecosystem restoration, such as Carpinus spp., so they should be preserved very thoroughly. The marshy ecosystem of about 27,720㎡ which is at the height of 600meters above sea level, west to North Gate of Mt. Gum-Jung Castle, has the high watertable formed naturally. The existence of the marshy at the near of the mountain top is a remarkably rare phenomenon, the preservation of as the marshy ecosystem is absolutely necessary. At present, this area is completely destroyed by the thoughtless use. Furthermore, the construction of the drainage due to the forest roads may cause the change of the waterable height of the marshy ecosystem. The construction of the forest road near to the to of the mountain, having th egood landscape and the historic relics, results in many problems with the landscape. Putting together, the construction of the forest roads should consider the totality of Mt. Gum-Jung instead of only considering forest preservation. Also the scientific method of a sustainable use should be sought, which fully incorporates the problems such as the width and size of the forest roads, the pavement methods and materials, and the choice of sites without ecological and landscape problems.

사회규범의 공공성에 관한 법가의 인식(2) : 한비자(韓非子)의 '인·의'(仁·義) 비판에 대한 유가의 응답 A Confucian Response to Han Fei-tzu's Critique on Benevolence

이승환 한국철학사상연구회 2003 시대와 철학 Vol.14 No.2

한비자는 공적영역에서 인의와 같은 도덕적 가치를 배격하고자 했다. 인의가 신하의 손에 의해 시행되면 신하의 세력이 확대되어 군주의 권위를 해치게 되고, 공정하고 객관적이어야 할 공적 세계에 인의라는 사적 도덕이 개입하게 되면 사회적 신뢰를 훼손 하게 되기 때문이다. 또한 인간의 본성은 비열하여 도덕으로 다스릴 수 없으며, 도덕의 시대는 가고 힘으로 다투는 시대가 되었다는 한비자의 시대인식은 결국 인의를 배격하고 법과 형벌만을 유일한 사회규범으로 여기게 만든다. 한비자의 이러한 입장에 대하 여 인의와 덕치를 주장하는 유가에서는 어떠한 응답을 할 것인가? 본고에서는 한비자 의 인의 비판에 대해 유가에서 내놓을 수 있는 가능한 응답들을 제시해보고자 하였다. 한비자와 유가의 비교적 고찰을 통하여, 서로 상충하는 듯이 보이는 양자간의 입장차 가 상당 부분 해소될 수 있으며, 두 사람의 주장은 서로 다른 차원에서 각기 효력을 지닌 주장이라는 점을 밝히고자 하였다. Han Fei-tzu, in his political theory, rejected moral virtues such as benevolence and righteousness. He was afraid that If the virtues of benevolence and righteousness were exercised by ministers rather than by the ruler, then the authority of the ruler would be seriously damaged. Moreover he was anxious about the collapse of social trust when private virtues are applied to the realm of public domain. Concerning Han Fei-tzu's rejection of moral virtues, what kind of answers could Confucian scholars give? In this paper, I tried to draw probable answers that Confucian scholars such as Confucius and Mencius would provide. Through a hypothetical conversation between Confucian scholars and Han Fei-tzu, I will show that those seemingly conflict and dichotomy between Confucian scholars and Han fei-tzu will be dismissed as a pseudo collision, and arguments made by each scholars have effectiveness and legitimacy in each's political context.

기질성 뇌장애 환자의 구조적 뇌영상과 비교한 저해상 전자기 단층 촬영 영상

이승환,권구형,박영민,김 현,이강준,정영조 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.3

Objectives : Patients with organic brain lesion can produce unique slow waves (delta and theta) in the EEG. Basic assumption of this study was that the low resolution electro magnetic tomography (LORETA), an inverse source localization program, can provide functional images representing increased slow wave activity in these patients compared to normal subjects. Methods : The current study was performed by 18 channels digital EEG for 10 patients whose organic deficit have been Visually confirmed by CT or MRI. The source images of slow wave (1-7 Hz) frequency were produced by LORETA-key program. Results : We found that in eight out of ten subjects, LORETA successfully found out the source regions which were very closely matched to their original brain lesions. However in two subjects whose organic brain lesions were too small (<1cm) and located out of gray matter, we failed to find any increased slow wave activity compared with normal control. Conclusion : We can conclude that LORETA could be a useful method to provide functional imaging in patients with gray matter deficits in their brain. Its usefulness and limitations were discussed.

악교정 수술 후 발생하는 신경회복에 대한 연구Ⅰ

이동근,조이수,민승기,오승환,정창주,이은택 대한악안면성형재건외과학회 2001 Maxillofacial Plastic Reconstructive Surgery Vol.23 No.2

Dysfunction of the inferior alveolar nerve indicated by various degree of numbness of the lower lip and chin is one of the few drawbacks of mandibular osteotomy, especially Bilateral Sagittal Split Ramus Osteotomy(BSSRO) and genioplasty. Although it has been recorded throughout the history of this techniques, it is true etiology poorly understood. In this study, 22 consecutive patients under class III malocclusiion impression and undergoing orthognathic surgery(BSSRO only 11 case, BSSRO with genioplasty 11 case) were studied using 4 neurosensory test(static light touch, directional discrimination, two-point discrimination, pin pressure nociception) with post OP 1 week, 2 weeks,4 weeks, 8 weeks, 12 weeks, 24 weeks, On control group, 10 members without trauma and nerve damage history, nerve test was accomplished. We concluded majority of patients return of sensation during post operative 24 weeks. Althought immediate nerve deficit are 92.2%, 97.2% 88.9% these are recovered to 25%, 35.72%, 10.71% at 24 weeks. Nerve recovery rate increased prominently between post 4 weeks and 8 weeks. There is no statistically difference about neurosensory deficit among the chin area. Neurosensory deficit more severe when the BSSRO with genioplasty group than the only BSSRO group. Immediate neurosensory deficit is larger left side than right side but after 6 months, there is no significantly difference between left side and right side. Static light touch and pin pressure nociception are more sensitive method of neurosensory deficit than two point discrimination.

참외 單性化 遺傳에 關한 硏究 : 1) 單性花의 遺傳機構와 實用形質에 關한 調査 1) Investigation on Genetical Mechanism of Monoecious Type and Practical Character

李昇雨,鄭德敎,金秉煥,金岩東 동국대학교 농림과학연구소 1971 農林科學 論文集 Vol.4 No.-

Using F_1 seed production on monecious flowers of Cucumis melo L., three of monoecious and four varities of dioecious were used as material in order to study inheritable mechanism and their characteristics. 1. Monoecious type were segregated 20 : 0 (1 : 0) from Go to G_1, 20 : 0 (1 : 0) F_1 between andromomoecious and 47 : 13 (3 : 1) as well as 33 : 7 (3 : 1) in F_2. Consequently it seems to be inherited by dominant single gene of AA in monoecious and recessive gene of aa in andromonoecious type. 2. However, it was guessed to be possessed of gene type that was effected by environment in monoecious type of U.S.S.R. 409. 3. Three varities of monoecious were poor condition in the practical quality aspect. The variety of U.S.S.R. 409 that was under the control of environment and it was extremly segregated quality has possiblity of useful quality selection compere with others respectably.

혀에 작용하는 capsaicin에 관한 감각 정보의 특성

이배환,김기석,김기영,진춘조,나흥식,홍승길 한국심리학회 1999 한국심리학회지 생물 및 생리 Vol.3 No.1

본 연구는 혀에 작용하는 capsaicin이 유발하는 감각 정보의 특성을 알아보기 위해 수행되었다. α-chloralose로 마취한 고양이에게 기계적 자극, 미각자극, capsaicin을 혀에 도포하고, 동통 유발 물질과 capsaicin을 혀의 동맥에 주입하면서 고삭신경과 설신경에서 신경의 활동을 기록하였다. 고삭신경에서 혀에 도포한 capsaicin에 대한 반응은 미각 자극 및 혀의 동맥에 주입한 동통 유발 물질에 대한 반응과 상관이 있었다. 혀의 혈관에 주입한 capsaicin에 대한 고삭신경의 반응은 혀에 도포한 capsaicin 및 혀의 혈관에 주입한 동통 유발 물질에 대한 반응과 상관이 있었다. 설신경에서 혀에 도포한 capsaicin에 대한 반응은 동맥에 주입한 동통 유발 물질에 대한 반응과 상관이 있었다. 혀의 혈관에 주입한 capsaicin에 대한 설신경의 반응은 혀에 도포한 capsaicin 및 혀의 혈관에 주입한 동통 유발 물질에 대한 반응과 상관이 있었다. 이러한 결과는 capsaicin이 혀에 작용할 때 동통뿐만 아니라 미각에 관한 정보도 유발한다는 것을 시사한다. 이때 미각에 관한 정보는 고삭신경을 통해 중추로 전달되며, 동통에 관한 정보는 설신경을 통해 전달되지만, 동통에 관한 정보가 고삭신경을 통해 전달될 가능성도 배제하지 못한다. The present study was performed to investigate the characteristics of sensory information produced by capsaicin in the tongue. Activities of the chorda tympani(CN) and lingual nerves(LN) were recorded while taste stimuli and capsaicin were being applied topically, and capsaicin and algesics were being injected intra-arterially to the tongue of cats anesthetized with α-chloralose. Responses of the CN fibers to topically applied capsaicin were correlated with those to taste stimuli and intre-arterially injected algesics. Responses of the CN fibers to intra-arterially applied capsaicin were correlated with those to topically applied capsaicin and intra-arterially injected algesics. Responses of the LN fibers to topically applied capsaicin were correlated with those to intra-arterially injected algesics. Responses of the LN fibers to intra-arterially aplied capsaicin were correlated with those to topically applied capsaicin and intra-arterially injected algesics. These results suggest that capsaicin provoke taste as well as pain sensation in the tongue. Taste information produced by capsaicin is conveyed to the brain via the CN and pain information via the LN. However, the possibility that pain information may be conveyed via the CN can not be excluded.

환경교육을 위한 초등학교 조경계획에 관한 연구

이영민,김석규,김승환 동아대학교 건설기술연구소 2000 硏究報告 Vol.24 No.2

Many of the urban children have little opportunities to contact with nature. Even if investigation of The Nature Study Center and historical relics gives them chances to experience nature, it is time consuming and costs a lot. Above all, this is now a continuous and daily education. Therefore we need to make school landscape easy to access, before the investigation of The Nature Study Center and historical relics. And we need to apply it to education. It will make children contact with nature spontaneously. Present school landscape is in due consideration of planting plan based on the conception of the school garden for students but it overemphasizes the meaning of modernistic landscape so it is just artificial and different from the quality of education. Moreover, we need educational school landscape plans that include the whole surroundings not only the inside base on the raising garden but also the outside of school. For this purpose, this research is the space conception and the space activity of design and elementary school landscape plan model for environment education.