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>

Analysis of Fire Evacuation Behavior in a Primary School Environment

Lee,Chang-Seop,Kim,Hong,A,Kilpatrick,W,Fitzpatrick 한국화재소방학회 1997 한국화재소방학회 학술대회 논문집 Vol.1997 No.-

The paper compares the statutory requirements for the design mid construction of primary schools in Korea and Scotland with respect to fire safety and examines the attitudes to, and the behavior in, evacuation scenarios of Primary school Pupils in both countries. The key behavioral issues examined are the effectiveness of fire safety training, the level of teacher dependency, the effect of spatial organization and gender differences both within and between Korea and Scotland.

Reduction of Spreading Thermal Resistance Using Vapor Chamber Heat Pipe

You-Seop Lee(이유섭),Jongseok Kim(김종석) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

This paper studies heat spreading aspect of a vapor chamber for chip cooling application. The vapor chamber is a flat-plate heat pipe which can be embedded in the base of a heat sink to reduce the spreading thermal resistance. The thermal behavior of the vapor chamber with acetone as working fluid and micro grooves for wick structure has been experimentally investigated. The employment of the vapor chamber could make the junction temperature of the chip decrease up to 10 K with a reduction of spreading thermal resistance of 0.4 K/W. Such a thermal spreading effect depends on the area ratio of the vapor chamber and heating element. A spreading thermal resistance analysis is performed using Lee's closed form correlation to estimate the spreading capability of the vapor chamber. The thermal behavior of the vapor chamber is also numerically studied using in a good agreement with the junction temperature measurement results.

중국 일대일로(一帶一路) 금융자금조달 모델에 관한 연구23)

徐逢敎 ( Seo,Bong-kyo38 ),崔洛燮 ( Choi,Nak-seop39 ),李賢泰 ( Lee,Hyun-tai40 ) 한중사회과학학회 2016 한중사회과학연구 Vol.14 No.2

This paper focuses on the financing problems of "One Belt and Road" initiatives of China. Chinese government plans several financing channels of "One Belt and Road" initiatives. First model is the using ``International Development Financial Institution`` such as AIIB(Asian Infrastructure Investment Bank). Second model is the PPP(Public-Private Partnership) model, which is received attentions these days. Chinese government declared the project financing principle in the "One Belt and Road" financing aspects, so PPP financing model will be more popular afterward. Third model is the using RMB(Runminbi) Internationalization. Chinese government want to finance RMB investment capital for "One Belt and Road" initiative. RMB Internationalization and "One Belt and Road" will expedite the oversea expansion of Chinese financial institutions. Korean financial companies must use the opportunity from "One Belt and Road" initiative. Most important area will be ASEAN countries and the cooperation with China will enhance competitions of the Korean manufacture companies.

선묘화법을 이용한 회화표현에 관한 비교연구

이정섭(Jung-Seop Lee) 한국엔터테인먼트산업학회 2009 한국엔터테인먼트산업학회논문지 Vol.3 No.1

미술을 그린다는 것으로부터 출발했다고 볼 때, 그린다는 것은 선으로부터 시작되었다는 것이 고대 벽화에 그려진 외곽선의 형태들에서 찿아 볼 수 있다. 우리가 흔히 알고 있는 선이란 무수히 많은 점들의 집합이다. 선은 그 차체만으로도 충분히 운동방향을 나타낼 수 있을 뿐 아니라, 인간의 내면세계를 표현하는데 중요한 요소라 할 수 있으며, 선을 긋는다는 그 자체만으로도 창조적 동기를 갖추는 시작점이 될 수 있는 것이다. 일반적으로 작품의 인상이 강렬한 이미지를 갖게 되는 것은 독특한 소재와 차별화된 구도 등 여러 요인도 있겠지만 동일한 대상의 표현방법도 작가마다 동기부여와 심상세계가 다름에 따라 작품에 표현되는 이미지도 각기 달라진다는 것을, 인상주의 이후로 현재까지 회화의 무한 가능성이 내포된 “선”의 성격을 작가 개인의 뚜렷한 감성을 그대로 표현하여 창조된 작품으로 지금까지 세계인들의 무한한 사랑을 받고 있는 고흐와, 자연형태에서 모티브를 빌려 새로운 표현을 얻고자, 덩굴풀이나 담쟁이 등 식물의 형태가 연상되는 파상곡선 아르누보 양식의 선구자인 클림트의 작품 사례를 살펴보고 “선묘화법”을 이용하고 있는 이정섭의 작품 변화과정과 비교하여 봄으로써 구상회화의 표현방식으로 선의 성격이 어떻게 이용되고, “선묘화법”이 현대 회화 표현기법에서 적응할 수 있는 가능성을 검증 해 본다. Line-drawing technique that is illustrated in the works of Gogh in the latter part of his life expresses his sensibilities from the nature with rough lines. Wasn’t his expressive format of composing the canvas vehemently at times while gentle at other times not his unique means of coping with his uncertain life environment? This could have been the volition of the artist attempting to pursue new changes. Expressive behavior of Gogh of mixing the paint on the canvas and making long lines would have been the expression of uncontrollable changes of his emotions that can only be felt on the site. As an artist confronts the Mother Nature, changes in cogitation are induced ceaselessly, because the emotions arising within due to blowing of wind, warm twinkle of sunlight and changes in the length of the shadow could be felt sufficiently differently. However, the lines illustrated in the self-portraits and figure paintings of Gogh, unlike the lines in his landscape paintings, are much shorter and expressed with uniform directionality. This is perhaps because he was able to maintain composure of his emotion when working indoors. Klimt used lines most in expressing the costumes or backgrounds of characters. This can be considered as usage as symbolic significance rather than to accurately express certain form. Semiotic forms, rectangles, triangle, circles and lines using the stems of plants are quietly flowing in alignment. Although these are thin and fragile lines, they induce gentle flow with elongation of collection of several lines while forming surfaces. These are straight lines at times and curved lines at others, thereby changing the ambience of the painting in accordance with the flow of such lines. Ultimately, flow of such lines in the works of Klimt is used as one of determinant expressive method of illustrating his intended ambience. Lines of Klimt form surfaces and become the element that determines the features of the surface. Lines illustrated in the works of Lee, Jung Seop, are defined as ‘lines of wind’. Even within the seemingly still space, the artist is carrying out conversation on the canvas with the gazes of viewers through the flow of wind with diverse range of length, thickness and colors as well as the directionality of the line that is ceaselessly moving. Such expressive technique of line was first introduced in 2001. Initially, it was only a flow of small lines, which at first may be recognized as pointillism. However, while the pointillism of the post-impressionists was expressed with points in primary colors, little lines in the works of Lee, Jung Seop are moving busily on the canvas. As though used as expressive method of sincerely conveying the momentary emotions in accordance with the flows of light and wind in the outdoor works, expressions include wide range of types of lines, while self-restraint and intended tranquil lines are flowing in the works done indoors. As illustrated above, it can be seen that each of the artists uses characteristics of lines with different significance in their expressive format of painting using line-drawing technique. As completely different significances can be endowed in accordance with how the lines are used, the line-drawing painting technique has been continuing to undergo progress, transcending space and time, until now.

Reusable Electrical Activity of the Heart Monitoring Patch for Mobile/Ubiquitous Healthcare

Lee, Jeong-Whan,Lee, Kang-Hwi,Lee, Young-Jae,Hong, Lee-Yon,Kim, Dong-Jun,Kim, Kyeong-Seop,Lee, Bongsoo,Lee, Myoungho Springer-Verlag 2009 JOURNAL OF MEDICAL SYSTEMS Vol.33 No.1

경북 최초의 신장이식 1례

이중현,김용섭,이정호,이창우,김상욱,이문섭,오민구,하달봉,이경섭 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

신장이식은 환자의 삶의 질을 높이고 거의 정상적인 사회생활을 가능하게 함으로써 말기신부전 환자의 3가지 신대체 요법(혈액투석, 복막투석, 신장이식) 중에 가장 효과적이고 각광받는 치료법이라 할 수 있다. 최근 들어 의료기술과 의학의 발달로 신장이식의 성공률은 과거에 비해 비약적으로 높아지고 있으며 국내에서도 점차 신장이식수술을 받는 환자가 증가하고 있으나 서울이나 다른 대도시에 비해 의료환경이 열악한 중소도시나 지방의 병원에서는 아직도 시행하지 못하고 있는 형편이다. 이에 저자들은 경북 최초로 자체 의료진에 의해 고혈압과 말기 신부전으로 동국대 포항병원에서 혈액투석을 받고 있던 32세의 남자환자에게 부인으로부터 신장을 제공받아 신장이식을 성공적으로 시행하였기에 문헌고찰과 함께 보고하고자 한다. Kidney transplantation is the preferred treatment modality for many patients with end-stage renal disease (ESRD), because it offers improved quality of life over both hemodialysis and peritoneal dialysis. Patients who do well after transplantation generally report improvement in vitality and freedom to return to the style of life that they experienced before their progression to ESRD. Recently, the success rate of kidney transplantation is greatly being increased as the surgical technique and immunosuppressive drugs are developed. Kidney transplantation is also popular in Korea which has good result. But, until now the general hospitals which are located at small city can't try the kidney transplantation because they don't have proper facilities and experts. We firstly experienced a case of kidney transplantation in a 32 years old man with hypertension and chronic renal failure at KyoungBuk province. So we report this case with references.

S-363 Chemical pleurodesis using mistletoe extracts via spray catheter during medical thoracoscopy

( Sun Hack Lee ),( Jung Seop Eom ),( Tae Hwa Kim ),( Kyu Min Lee ),( Ji Yeon Shin ),( Han Na Lee ),( Bo Hye Song ),( Yong Ki Sim ),( Geewon Lee ),( Jeong Ha Mok ),( Hyo Yeong Ahn ),( Min Ki Lee ) 대한내과학회 2016 대한내과학회 추계학술대회 Vol.2016 No.1

We present three cases of successful chemical pleurodesis with a liquid solution of mistletoe extract using a spray catheter during medical thoracoscopy. The medical thoracoscopy was performed in all presented cases to remove pleural effusion and conduct chemical pleurodesis to manage symptomatic malignant pleural effusion. A spray catheter was used to instill the mistletoe extract evenly into the pleural cavity, and there were no pleurodesis-related complications. Respiratory symptoms caused by pleural effusion improved after pleurodesis, and successful pleurodesis was maintained for more than 3 months after medical thoracoscopy in all three patients. Lee and Colt reported that instilling lidocaine via a spray catheter is effective for pain control before chemical pleurodesis during medical thoracoscopy. Using a spray catheter in the same way, we performed pleurodesis with a mistletoe extract via a spray catheter in three patients with MPE. A complete response, defined as no pleural effusion within 4 weeks after the last pleurodesis6, was achieved in all three patients. Several studies have used liquid mistletoe extract via a chest tube for chemical pleurodesis. Stumpf et al. reported that the overall response to mistletoe extract pleurodesis was 72% in 20 patients with MPE. Mistletoe extract, which was previously verified as an effective sclerosant for pleurodesis via a chest tube, could be evenly sprayed into the pleural cavity during thoracoscopy using a spray catheter. Distributing the sclerosant evenly into the pleural cavity with a spray catheter may lead to successful pleurodesis, particularly in patients who underwent medical thoracoscopy. In conclusion, We found that instilling the mistletoe extract using a spray catheter was an effective pleurodesis method and could possibly be performed as an alternative to talc poudrage.

기종성 신우신염 1례

이재욱,구정태,서정일,양창헌,이정호,이동철,이영현,이활,이경섭 동국대학교 경주대학 1997 東國論集 Vol.16 No.1

기종성 신우신염은 주로 당뇨병환자나 폐쇄성 요로질환을 가진 환자에 발생하며 특징적으로 신실질 및 그 주위조직에 가스를 형성하면서 심한 조직괴사를 일으키는 매우 드문 급성 화농성 신감염으로 사망률이 높은 질환이다. 이 질환은 1989년 Kelly와 MacCallum에 의해 처음 보고된 이래 외국문헌에 약 90례 정도가 보고되어 있으며 국내에는 28례가 보고되어 있다. 수액 및 전해질 보충, 인슐린 투여를 통한 적절한 혈당조절 및 항생제 투여등의 내과적 치료와 절개배농 및 신적출술등의 수술적 치료 방법이 있다. 내과적 치료로 가스의 감소가 없는 경우에는 즉각적인 수술적 치료를 시행하여야하므로 이 가스변화에 대한 추적관찰이 중요하다 하겠다. 본 저자들은 당뇨병환자에서 발생한 기종성 신우신염 1례를 내과적 요법을 치험하였기에 문헌고찰과 함께 보고하고자 한다. Emphysematous pyelonephritis is rare, life-threatening infection of the renal parenchyma and perirenal tisseue. This disease is characterized by the production of intrarenal and perirenal gas and is frequently encountered in patients with diabetes mellitus or urinary obstruction. We experienced a case of emphysematouse pyelonephritis in a 62 years old women with poorly controlled diabetes mellitus who had been managed with medical theraphy. So we report this case with a review of the referenced literatures.

NPS 2143, a selective calcium-sensing receptor antagonist inhibits lipopolysaccharide-induced pulmonary inflammation

Lee, Jae-Won,Park, Hyun Ah,Kwon, Ok-Kyoung,Park, Ji-Won,Lee, Gilhye,Lee, Hee Jae,Lee, Seung Jin,Oh, Sei-Ryang,Ahn, Kyung-Seop Elsevier 2017 Molecular immunology Vol.90 No.-

<P>NPS 2143, a novel and selective antagonist of calcium-sensing receptor (CaSR) has been reported to possess anti-inflammatory activity. In the present study, we examined the protective effect of NPS 2143 on lipopolysaccharide (LPS)-induced acute lung injury (ALI). NPS 2143 pretreatment significantly inhibited the influx of inflammatory cells and the expression of monocyte chemoattractant protein-1 (MCP-1) in the lung of mice with LPS-induced ALI. NPS 2143 decreased the levels of neutrophil elastase (NE) and protein concentration in the bronchoalveolar lavage fluid (BALF). NPS 2143 also reduced the production of inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in the BALF and serum. In addition, NPS 2143 attenuated the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and increased the activation of AMP-activated protein kinase (AMPK) in the lung. NPS 2143 also downregulated the activation of nuclear factor-kappa B (NF-kappa B) in the lung. In LPS-stimulated H292 airway epithelial cells, NPS 2143 attenuated the releases of IL-6 and MCP-1. Furthermore, NPS 2143 upregulated the activation of AMPK and downregulated the activation of NF-kappa B. These results suggest that NPS 2143 could be potential agent for the treatment of inflammatory diseases including ALI.</P>