• Title/Summary/Keyword: Hwang Sung-Ha

Search Result 542, Processing Time 0.034 seconds

The Development of ASK Modulator for using Automatic Gate Passing System (자동게이트통관시스템에 사용하기 위한 ASK 변조기 MMIC 구현)

  • Jang, Mi-Sook;Ha, Young-Chul;Hwang, Sung-Beam;Moon, Tae-Jung;Hur, Hyuk;Song, Jeong-Geun;Hong, Chang-Hee
    • Proceedings of the IEEK Conference
    • /
    • 2001.06b
    • /
    • pp.233-236
    • /
    • 2001
  • We have designed and fabricated ASK modulator MMIC operating at 5.8GHz for OBE used in AGPS (Automatic Gate Passing System). ASK modulator MMIC was designed to apply a sing1e supply voltage of 3V to the drain in order to decrease ACP (Adjacent Channel Power). The measurement result of this chip exhibits on/off characteristic over 30dB. The design parameters are optimized through ADS simulation tool. The layouts and fabrication o( ASK Modulator MMIC were designed and fabricated by using ETRI 0.5${\mu}{\textrm}{m}$ MESFET library. The chip sizes were 1mm $\times$1mm. The performance analysis of the implemented ASK Modulator based on the design parameters is accomplished.

  • PDF

A Highly Sensitive Determination of Bulk Cu and Ni in Heavily Boron-doped Silicon Wafers

  • Lee, Sung-Wook;Lee, Sang-Hak;Kim, Young-Hoon;Kim, Ja-Young;Hwang, Don-Ha;Lee, Bo-Young
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.7
    • /
    • pp.2227-2232
    • /
    • 2011
  • The new metrology, Advanced Poly-silicon Ultra-Trace Profiling (APUTP), was developed for measuring bulk Cu and Ni in heavily boron-doped silicon wafers. A Ni recovery yield of 98.8% and a Cu recovery yield of 96.0% were achieved by optimizing the vapor phase etching and the wafer surface scanning conditions, following capture of Cu and Ni by the poly-silicon layer. A lower limit of detection (LOD) than previous techniques could be achieved using the mixture vapor etching method. This method can be used to indicate the amount of Cu and Ni resulting from bulk contamination in heavily boron-doped silicon wafers during wafer manufacturing. It was found that a higher degree of bulk Ni contamination arose during alkaline etching of heavily boron-doped silicon wafers compared with lightly boron-doped silicon wafers. In addition, it was proven that bulk Cu contamination was easily introduced in the heavily boron-doped silicon wafer by polishing the wafer with a slurry containing Cu in the presence of amine additives.

Biochemical and Structural Analysis of Hormone-sensitive Lipase Homolog EstE7: Insight into the Stabilized Dimerization of HSL-Homolog Proteins

  • Nam, Ki-Hyun;Park, Sung-Ha;Lee, Won-Ho;Hwang, Kwang-Yeon
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.9
    • /
    • pp.2627-2632
    • /
    • 2010
  • Hormone sensitive lipase (HSL) plays a major role in energy homeostasis and lipid metabolism. Several crystal structures of HSL-homolog proteins have been identified, which has led to a better understanding of its molecular function. HSL-homolog proteins exit as both monomer and dimer, but the biochemical and structural basis for such oligomeric states has not been successfully elucidated. Therefore, we determined the crystal structure of HSL-homolog protein EstE7 from a metagenome library at $2.2\;{\AA}$ resolution and characterized the oligomeric states of EstE7 both structurally and biochemically. EstE7 protein prefers the dimeric state in solution, which is supported by its higher enzymatic activity in the dimeric state. In the crystal form, EstE7 protein shows two-types of dimeric interface. Specifically, dimerization via the external ${beta}8$-strand occurred through tight association between two pseudosymmetric folds via salt bridges, hydrogen bonds and van der Waals interactions. This dimer formation was similar to that of other HSL-homolog protein structures such as AFEST, BEFA, and EstE1. We anticipate that our results will provide insight into the oligomeric state of HSL-homolog proteins.

Preparation and Characterization of Cd-Free Buffer Layer for CIGS by Chemical Bath Deposition (화학습식공정을 이용한 CIGS 태양전지용 Cd-free 버퍼층 박막 제조 및 특성 분석)

  • Hwang, Dae-Kue;Jeon, Dong-Hwan;Sung, Shi-Joon;Kim, Dae-Hwan;Lee, Dong-Ha;Kang, Jin-Kyu
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2012.03a
    • /
    • pp.146-148
    • /
    • 2012
  • In our study, we have focused on optimizing good quality of ZnS buffer layer by chemical bath deposition (CBD) from a bath containing $ZnSO_4$, Thiourea and Ammonia in aqueous solution onto CIGS solar cells. The influence of deposition parameter such as pH, deposition temperature, stirring speed played a very important role on transmission, homogeneity, crystalline of ZnS buffer layer. The transmission spectrum showed a good transmission characteristic above 80% invisible spectral region. CIGS thin flim solar cell with ZnS buffer layer has been realized with the efficiency of 14.2%.

  • PDF

Structural Analysis of Oligosaccharides of a Plant Glycoprotein (식물 유래 당단백질의 당질 구조 분석)

  • Bae, Jae-Woo;Park, Byung-Tae;Yoon, Doo-Chun;Kim, Joo-Young;Hwang, Hye-Sung;Park, Hyun-Joo;Na, Jong-Chun;Kim, Ha-Hyung
    • YAKHAK HOEJI
    • /
    • v.54 no.6
    • /
    • pp.449-454
    • /
    • 2010
  • The glycosylation of glycoproteins from mammalian or plants can affect their efficacy, stability, solubility, and half-life. In the present study, we investigated plant glycosylation and their relative intensity (%) in a plant carbohydratebinding protein with the hemagglutination and antiproliferative activities. The hemagglutination activity on the deglycosylated protein was decreased as a 16-fold than that of intact glycoprotein. Using the HPLC with fluorescence detector and mass spectrometer, the major eight bi- or triantennary oligosaccharides containing xylose, fucose, mannose, galactose, and N-acetylglucosamine were identified and structurally characterized. The present results indicate that the oligosaccharides on this plant glycoprotein is necessary for their own property.

Development of a Selective Medium for the Fungal Pathogen Fusarium graminearum Using Toxoflavin Produced by the Bacterial Pathogen Burkholderia glumae

  • Jung, Boknam;Lee, Sehee;Ha, Jiran;Park, Jong-Chul;Han, Sung-Sook;Hwang, Ingyu;Lee, Yin-Won;Lee, Jungkwan
    • The Plant Pathology Journal
    • /
    • v.29 no.4
    • /
    • pp.446-450
    • /
    • 2013
  • The ascomycete fungus Fusarium graminearum is a major causal agent for Fusarium head blight in cereals and produces mycotoxins such as trichothecenes and zearalenone. Isolation of the fungal strains from air or cereals can be hampered by various other airborne fungal pathogens and saprophytic fungi. In this study, we developed a selective medium specific to F. graminearum using toxoflavin produced by the bacterial pathogen Burkholderia glumae. F. graminearum was resistant to toxoflavin, while other fungi were sensitive to this toxin. Supplementing toxoflavin into medium enhanced the isolation of F. graminearum from rice grains by suppressing the growth of saprophytic fungal species. In addition, a medium with or without toxoflavin exposed to wheat fields for 1 h had 84% or 25%, respectively, of colonies identified as F. graminearum. This selection medium provides an efficient tool for isolating F. graminearum, and can be adopted by research groups working on genetics and disease forecasting.

Application of Stormwater Detention Facilities for Lacking Capacity of Sewers (강우시 도시 하수관거통수능부족 해소를 위한 우수저류시설의 적용)

  • Kim, Young-Ran;Kim, Jin-Young;Hwang, Sung-Hwan
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.18 no.3
    • /
    • pp.343-350
    • /
    • 2004
  • For the last two decades, Seoul has always been affected by large floods. As climate change causes more frequent localized heavy rains exceeding the capacity of sewer or river to discharge water, flood damage is expected to increase. Under the situation, detention facilities for lacking capacity of sewers can control stormwater runoff to reduce flood damage in urbanized areas. In this study, in order to reduce flood damage in Cheonggyecheon areas, the capacity of detention facilities was decided to make up for the lacking capacity of main sewers in case of the rainfall in July, 2001 as large flood. The average amount of stormwater detained in eight Cheonggyecheon drainage areas is $235.09m^3/ha$. Location and size of stormwater detention facilities is designed to have effects in short term by targeting the reduction of flood damage. Schools and parks are suggested as optimal locations where detention facilities are constructed in drainage areas.

Cost-Benefit Analysis of the Farmer's Health Center Project (FHCP) in Rural Korea (농업인건강관리실 사업의 비용편익 분석)

  • Hwang, Dae-Yong;Kang, Kyeong-Ha;Lee, Soon-Sung;Ko, Jeong-Sook;Oh, Seung-Young
    • Journal of Agricultural Extension & Community Development
    • /
    • v.13 no.2
    • /
    • pp.313-327
    • /
    • 2006
  • This study aims to examine the operating status of the Farmer's Health Center Project and the validity of its business using the benefit-cost analysis. As the pilot project of the Rural Development Adminstration from 1996, a total of 884 Farmer's Health Centers were established until 2004. Internal information of the RDA management unit was used for the analysis. A questionnaire with an interview was also performed with 70 over 468 Centers that had been established from 2001 to 2004. Results were as follows. 1) The Center was mainly used by elderly over 60 years, which took 71.4%. Winter was the most popular season for visiting. 2) Approximately 71% of the manager of the Center pointed out the deficiency of fuel cost as the most difficulty in operating the Center. 3) Users were moderately satisfied with facility and the effect of its use, which took 3.5 point over 5 scale. 4) For the cost-benefit analysis on the Centers, both 5% of social discount rate and 15 years of use term were assumed. Subsequently, the Net Present Value was 3,134 million won, which certified the validity of the business.

  • PDF

Study on the single power supply design of PLS-II injection kicker (PLS-II 인젝션 키커의 단일전원장치 설계에 관한연구)

  • Son, Yoon-Kyoo;Jang, Sung-Duck;Hwang, Woon Ha;Lee, Byung-Joon;Choi, Jae-Young
    • Proceedings of the KIEE Conference
    • /
    • 2015.07a
    • /
    • pp.1197-1199
    • /
    • 2015
  • PLS-II 키커 모듈레이터는 마그넷 코일 4개에 펄스전원을 공급하고 있다. 에너지 저장용 커패시턴스 합성 값은 $3.2{\mu}F$이고, 두 개의 회로로 커패시턴스 $1.6{\mu}F$로 나뉘어져 있다. 키커 마그넷 코일 두 개를 직렬연결하고 두 개 회로를 병렬구조로 하여 펄스 폭 $6.8{\mu}s$, 전류 20 kA, 운전주파수 10 Hz로 운전되고 있다. 커패시터와 코일의 직렬공진에 의해 에너지를 전달하는 직렬공진회로이다. 인덕턴스를 줄일 목적으로 전원장치는 키커 마그넷 가까이에 설치되어있다. 이것은 펄스폭에 영향을 미치게 되며 운전전류에 민감해서 그 값이 커지게 되면 입력공급 전압이 높아지게 된다. 장치의 운영적인 측면에서 고장이나 키커 모듈레이터 내부에 문제가 발생 하였을 경우 저장링 터널에 설치되어있는 전원을 점검하기 위해서는 빔 운전을 중단하고 접근을 해야 하는 불편함이 있다. 키커 모듈레이터 전원을 단일전원을 하고자 하는 궁극적인 목적은 입사효율을 높이기 위함이며, 입사되는 키커의 변수를 조정하고자 한다. 또한, 정비의 용이성과 입사 시 키커의 전압, 전류를 개별적으로 조정이 가능하게 단일전원으로 장치를 제작하고자 한다. 본 논문에서는 단일전원의 설계와 실험내용을 소개하고자 한다.

  • PDF

A Structure on Classification Service System of Internet Documents (인터넷 문서의 자동분류 서비스 시스템에 관한 구현)

  • Hwang Sung-Ha;Choi Kwang-Nam;Lee Dae-Kyu;Lee Sang-Ho
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2005.11a
    • /
    • pp.66-71
    • /
    • 2005
  • Using for the internet information is easy or difficult. The effort to obtain the useful information is developed the various technique such as search as well as the information repository, classification, processing and the utilization. Specially, such developments are remarkable to the Agent of various uses and the classification, conversion in processing techniques. The study introduces the classification service system of internet documents which is processing from the repository of internet information to the automatic classification and search service.

  • PDF