결정질 실리콘 태양전지용 실리콘 기판의 표면 미세구조에 따른 곡강도 특성

이준성,권순우,박하영,김영도,김형준,임희진,윤세왕,김동환,Lee, Joon-Sung,Kwon, Soon-Woo,Park, Ha-Young,Kim, Young-Do,Kim, Hyeong-Jun,Lim, Hee-Jin,Yoon, Se-Wang,Kim, Dong-Hwan 한국재료학회 2009 한국재료학회지 Vol.19 No.1

The influence of various surface morphologies on the mechanical strength of silicon substrates was investigated in this study. The yield for the solar cell industry is mainly related to the fracturing of silicon wafers during the manufacturing process. The flexural strengths of silicon substrates were influenced by the density of the pyramids as well as by the size and the rounded surface of the pyramids. To characterize and optimize the relevant texturing process in terms of mechanical stability and the fabrication yield, the mechanical properties of textured silicon substrates were investigated to optimize the size and morphology of random pyramids. Several types of silicon substrates were studied, including the planar type, a textured surface with large and small pyramids, and a textured surface with rounded pyramids. The surface morphology and a cross-section of the as-textured and fractured silicon substrates were investigated by scanning electron microscopy.

L1210과 HL60 암세포에 대한 야생식물의 세포독성 검색

이준성,민병선,배기환,Lee, Jun-Sung,Min, Byung-Sun,Bae, Ki-Hwan 한국생약학회 1996 생약학회지 Vol.27 No.3

For the search of anticancer compounds from natural products, 43 plants were extracted with benzene and methanol, separately, and the extracts were screened for the cytotoxicity against L1210 and HL60 cancer cell lines. From the results, 22 samples in benzene extracts showed cytotoxicity against L1210 cells and 23 samples against HL60 cells, respectively. However, any methanol extracts did not exhibit cytotoxicity against two cancer cell lines, it suggested that cytotoxic compounds seemed to have low polarity. $ED_{50}$ values less than $5\;{\mu}g/ml$ were observed in 14 and 9 samples in benzene extracts against L1210 and HL60 cancer cells, respectively.

건성안 환자에서 쇼그렌증후군의 빈도 및 임상양상

이준성,최원,이신석,윤경철.Jun Sung Lee. MD. Won Choi. MD. Shin Seok Lee. MD. Kyung Chul Yoon. MD. PhD 대한안과학회 2012 대한안과학회지 Vol.53 No.4

Purpose: To investigate the prevalence and clinical aspects of Sjögren syndrome in patients who were diagnosed with dry eye syndrome in Korea. Methods: The medical records of patients who were diagnosed with dry eye syndrome in a dry eye clinic during a 2-year period (March 2008 to March 2010) and were followed up for more than 3 months were reviewed retrospectively. Results: A total of 206 patients were included in the present study. Fifty-eight patients (28%) had Sjögren syndrome and 39 patients (19%) showed primary Sjögren syndrome. Sjögren syndrome patients showed poorer results than non-Sjögren syndrome patients in ocular surface disease index score (OSDI), tear break up time, Schirmer test score, and ocular surface staining score using the Oxford scheme (p < 0.05). Among the patients with primary Sjögren syndrome, 27 patients were SSA (anti-Ro antibodies) or SSB (anti-La antibodies) positive and 12 patients were sero-negative. There were no statistically significant differences in objective or subjective parameters between the sero-positive and sero-negative groups. Conclusions: Sjögren syndrome was observed in 28% of all dry eye patients, in two-thirds of severe dry eye patients. Sjögren syndrome patients showed more severe clinical aspects than dry eye patients with non-Sjögren syndrome. Diagnosing Sjögren syndrome through systemic evaluation is necessary in the patients with severe dry eye. J Korean Ophthalmol Soc 2012;53(4):499-504

미세각막절개도를 이용한 데스메막박리 각막내피층판이식술의 국내 장기 임상 결과

이준성,박영걸,윤경철,Jun Sung Lee,Yeoung Geol Park,Kyung Chul Yoon 대한안과학회 2010 대한안과학회지 Vol.51 No.11

Purpose: To evaluate the long-term results of Descemet’s stripping automated endothelial keratoplasty in Korea (DSAEK). Methods: Seven patients with bullous keratopathy who underwent DSAEK and who were followed-up for more than 18 months were reviewed retrospectively. Best corrected visual acuity, refraction, corneal thickness, and endothelial cell count were examined before and after surgery. Results: The mean follow-up period was 19.9 ± 2.9 months (18 to 24 months), and the mean age was 61.42 ± 10.13 years (46 to 76 years). Six patients (85.7%) showed successful results after surgery. Best corrected visual acuity (logMAR) was significantly improved from 1.62 (median) to 1.15 (median) (p = 0.027) at one month after surgery and was maintained until the final follow-up period. There were no statistical differences in spherical ametropia or astigmatism before or 18 months after the operation. Graft failure was observed in one case, in which penetrating keratoplasty was performed 12 months after DSAEK. Conclusions: Long term results of DSAEK showed fast visual recovery, low ametropia and astigmatism. DSAEK may be a good option for the surgical management of corneal endothelial disease. J Korean Ophthalmol Soc 2010;51(11):1431-1437

확률론적 파괴역학을 도입한 CANDU 압력관의 예리한 결함에 대한 건전성평가

이준성,곽상록,김영진,박윤원,Lee, Jun-Seong,Gwak, Sang-Rok,Kim, Yeong-Jin,Park, Yun-Won 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.4

This paper describes a probabilistic fracture mechanics(PFM) analysis based on Monte Carlo(MC) simulation. In the analysis of CANDU pressure tube, the depth and aspect ratio of an initial semi-elliptical surface crack, a fracture toughness value and delayed hydride cracking(DHC) velocity are assumed to be probabilistic variables. As an example, some failure probabilities of piping and CANDU pressure tube are calculated using MC method with the stratified sampling MC technique, taking analysis conditions of normal operations. In the stratified MC simulation, a sampling space of probabilistic variables is divided into a number of small cells. For the verification of analysis results, a comparison study of the PFM analysis using other commercial code is carried out and a good agreement was observed between those results.

L1210 및 HL60 Cell에 대한 연교의 세포독성 성분

이준성(Jun Sung Lee),민병선(Byung Sun Min),배기환(Ki Hwan Bae) 대한약학회 1996 약학회지 Vol.40 No.4

Forsythiae Fructus was studied on cytotoxic activities for the purpose of finding out active consituents against L1210 and HL60 cells. To isolate the active ones, the methanolic extract was partitioned into water insoluble and water soluble fractions. Furthermore, the water soluble fraction was fractionated into four parts, n-hexane, benzene, ethylacetate and water fractions. Among these, the water insoluble fraction showed the most potent cytotoxic activities on L1210 and HL60 cells in vitro. The water insoluble fraction was applied to silica gel column chromatography and divided into 5 fractions(fr. 1-5). The active constituents I and II were isolated from fr.2 and 3, respectively, by repeated silica gel column chromatography and recrystallization. The constituents were identified as 3beta-acetylbetulinic acid and betulinic acid by means of physicochemical data. The ED50 values of 3beta-acetylbetulinic acid and betulinic acid were 9.10 and 16.43mcg/ml against L1210 cells and 2.72 and 2.41mcg/ml against HL60 cells, respectively.

직접 구동형 브러시리스 DC 모터 구동용 직접회로의 설계

이준성 ( Jun-sung Lee ) 한국고등직업교육학회 2000 한국고등직업교육학회논문집 Vol.1 No.4

This paper presents a monolithic integrated circuit design for a full wave linear Direct-Drive motor driving. It consists of hall amplifiers, direction control circuits, rotation switches, feedback amplifiers and output current driving circuits. The generated signal from the hall devices is applied to the hall amplifier, then is transmitted to the output port to drive a motor using the linear driving method. Since the servo control circuit is controlled by the motor revolution count, an external servo control circuit controls the output driving currents, then this circuit converts difference between the reference clock and the motor revolution count into current. This current is feedback to the input of the motor driving IC. The novel features of the circuit are high current driving capability, a current gain independent of power supply, temperature and process variations. The stand-by current is 2.5[mA] and maximum current driving capability is 1.2[A] at 12[V] of supply voltage and jitter is measured less than 1[㎲]. The circuit has been designed by a 8[㎛], 40[V] bipolar technology and reduces the die area which is about 10.5[mn²].

고속 암호 보조 프로세서의 설계 및 FPGA 구현

이준성 ( Jun-sung Lee ) 한국고등직업교육학회 2001 한국고등직업교육학회논문집 Vol.2 No.4

In this paper a VLSI design of cryptographic coprocessor, which can implements DES, Triple-DES and SEED encryption algorithm is described. To improve clock frequency, online precomputation scheme for round key is used. To apply the co-processor to various applications, four operating modes such as ECB CBC, CFB and OFB are supported. The cryptographic co-processor is designed using UMC 0.25[㎛] CMOS technology and consists of about 47,000 gates and operating 100[MHz] clock frequency.

Cu-zeolite base SCR의 loading량에 따른 NOx 정화 성능 거동 연구

이준성(Jun Sung Lee),여권구(Gwon-koo Yeo),임원미(Won-Mi Lim),차문순(Moon-soon Cha) 한국자동차공학회 2016 한국자동차공학회 부문종합 학술대회 Vol.2016 No.5

동북공정 종료 후 중국학계의 고구려 ‘대외관계사’ 연구 동향

이준성(Lee Jun-Sung) 한국고대학회 2017 先史와 古代 Vol.- No.53

동북공정이 종료된 2007년 이후 중국 학계에서 제출된 고구려 ‘대외관계사’ 논문은 동북공정 기간 정리된 ‘번속체제’의 영향을 크게 받았다는 특징을 지닌다. 대다수의 연구는 고구려와 중국 왕조의 관계가 ‘일국관계’임을 전제로 진행된 것이다. 반면 조공책봉제도의 성격과 관련 하여 그것을 고대 동아시아의 지역질서로 파악하는 연구들도 일부 있다. 그러나 이 경우에도 동아시아 세계의 성립과 발전을 오직 漢化라는 입장으로만 설명하여, 중국 중심사관에서 벗어나지 못하는 모습을 보이고 있었다. 한편, 돌궐이나 유연 등 북방민족과의 관계와 관련된 연구는 여전히 미흡하다는 점 역시 중국 학계의 인식이 여전히 중원왕조 중심의 관계 해명에 치중되어 있음을 방증한다. 이는 동아시아 세계가 중국 중심의 일원적 국제질서가 아닌 복수의 국제질서로 구성되어 있었다는 점을 시야에 넣지 못한 한계로 생각할 수 있다. The studies on Goguryeo’s ‘History of Foreign Relations’ submitted to the academic circles of China after 2007 when the Northeast Project of China ended show the characteristic that they are all greatly influenced by the ‘Fanshu Theory’ which was established during the Northeast Project period. Most studies were conducted based on the premise that the relations between Goguryeo and Chinese Dynasties were ‘One Country Relations.’ On the other hand, there are studies that see the characteristic of the Tributary Appointment System as the regional order of the ancient East Asia. However, such studies also explained the formation and development the East Asian world only based on the sinicization, failing to move away from the Sinocentric historical view. The fact that there are still not many studies about the relationship with northern races such as Gokturks or Rouran Khaganate also circumstantially evidence that the Chinese academic circles still focus on elucidating the relations centering on the Central Plains Dynasties. This can be attributed to the limit that Chinese academic circles have due to the exclusion of the idea that the East Asian world was under the influence of multiple international order not under the unitary international order centering on China in their vision.