574(H) X 489(V)개의 화소를 가지는 CCD형 촬영소자

허연철,이종덕 경북대학교 센서기술연구소 1990 센서技術學術大會論文集 Vol.1 No.1

수평으로 574개, 수직으로 489개의 화소를 가지는 1/2인치 CCD형 촬영 소자를 설계하고 제작하였다. 오버플로우 드레인의 동작을 이해하고 이를 효과적으로 이용한 설계를 위하여 광다이오드의 수직방향 전위분포를 계산하였고 전위분포의 간접적 검증 방법으로 펀치쓰루 전류를 측정하여 펀치쓰루가 일어나기 시작하는 바이어스 조건을 얻어서 계산치와 비교하는 방법을 사용하였다. BCCD의 최대 전위와 최대 신호 저장 용량을 BC MOSFET를 이용하여 측정된 전류로부터 계산하여 암신호와 구동 클락의 효율성을 고려할 때 전달단 구동 클락의 전압과 전달단의 크기가 타당하다는 결론을 얻었다. 출력단으로 쓰이는 이단 소스 플로워의 주파수 특성을 측정하고 SPICE를 이용한 모의 실험도 병행하여 30만 화소 정도의 촬영 소자에는 사용가능하나 더 높은 해상도를 가지는 촬영 소자에서는 고주파에서 이득이 작아지기 때문에 적용상에 어려움이 있음을 알았다. A 1/2-inch interline CCD image sensor with 574(H)X489(V) pixels has been designed and fabricated. The chip is compatible with the NTSC system. The vertical potential profile of a photodiode is calculated to analyze the VOFD action and the measurement of the punchthrough edge conditions is adopted as indirect verification of the profile. The maximum potential and the charge storage capability of BCCD are also calculated with the measured current from BCMOSFET and it is concluded that the storage capability and the voltage level of operation clock are reasonable in terms of the dark signal and the efficiency of clock pulse. The frequency response of the two stage source follower is also simulated by SPICE and measured for the investigation of the limit of the operation frequency. Its gain is sufficient for image sensor with about 300000 pixels. But it is not suitable for an image sensor with more than one million pixels since its gain is too small at the high frequency.

이중필름 수막시스템의 에너지 절감 효과

남상운,허연정,심옥자,심상일,이호상 안성산업대학교 1998 論文集 Vol.30 No.-

This study was carried out to investigate energy saving effect and thermal insulation characteristics of double film water curtain system during the coldest season in greenhouse. A double film water curtain system is a ground water spraying system between double layered plastic film, and it is able to make uniform water curtain. The experimental greenhouses were plastic greenhouses of two types. A type-Ⅰ was a two-thirds arched shape and its area was 350㎡ . A type-Ⅱ was a triangle shape and its area was 190㎡. Both greenhouses were cultivated with cactus. The minimum outside air temperature ranged was -2.6 to -16.7℃ and nocturnal ambient mean temperature was -6.5℃. The experimental greenhouses have maintained the air temperature above 2℃ of type-Ⅰ and 8℃ of type-Ⅱ. The ground water spraying flow rates of these greenhouses were 7.0ℓ/㎡hr of type-Ⅰ and 4.3ℓ/㎡hr of type-Ⅱ. The overall heat transfer coefficient of type-Ⅰ greenhouse was calculated at 1.97 kcal//㎡hr℃ and type-Ⅱ was 1.44 kcal/㎡hr℃. The energy saving rate of type-Ⅰ greenhouse was estimated and 78.1% and type-Ⅱ was 98.9%.

자가 면역성 간염에서 자가항체의 발현 양상과 스테로이드 치료의 효과

박기오,채경훈,허원석,강윤세,정재훈,김연수,문희석,이엄석,김선문,이병석,김남재,이헌영 충남대학교 의과대학 의학연구소 2003 충남의대잡지 Vol.30 No.1

목적 : 최근 8년간 본원에서 경험한 자기면역성 간염의 혈액학적 특징과 스테로이드의 치료효과를 알아보고자 본 연구를 시행하였다. 방법 : 1996년 이후부터 2002년까지 충남대학교 병원에서 1999년 International Autoimmune Hepatitis Group(LAHG)에서 제시한 수정 진단 기준안에 의거하여 총 진단점수가 probable 이상에 해당하는 환자들을 대상으로 임상적 특징, 검사실 및 조직 소견과 스테로이드와 azathioprine의 치료 효과를 후향적으로 조사하였다. 결과 : 9예의 환자들은 여성이 78%, 40대가 많았고, 급성 발병이 33.3%, 피로감, 식욕부진 및 황달 등이 나타났으며, 항핵항체가 55.6%에서 그리고 항평활근 항체가 77.8%에서 양성이었고, 동반 질환은 류마치스 관절염이 2예, 특발성 혈소판 감소증 1예, Henoch-Sch nlein 자반증 및 그레브스병이 각각 1예 씩이었다. 7예에 대해서 스테로이드와 azathioprine으로 치료하여 생화학적 임상적 완해가 이루어져서 유효한 치료 결과를 얻었다. 결론 : 자가면역성 간염은 우리 나라에서 원인을 찾을 수 없는 만성 간질환의 경우, 특히 중년여성에서 다른 자가면역성 질환이 동반되었을 때 자가면역성 간염을 의심하여 자가항체 선별검사를 시행해 보아야 할 것으로 생각된다. 향후 다기관 연구를 통하여 좀 더 많은 증례를 모으고 전향적인 연구를 시행하여야 할 필요가 있다. Although autoimmune hepatitis(AIH) is common in western contries, some studties have been reported in Korea. The aim of the study was to analyze the clinical and histological features and expression pattern of the autoantibody and to examine clinical course of AIH in Korea. For 9 patients diagnosed as having AIH in our hospital since 1996, we reviewed medical records and analyzed clinical and laboratory findings retrospectively. They had a probable or definite AIH according to the revised criteria of International AIH group. The mean age was 42.7(21∼68)years and 7(77.8%) were female. Three of them(33.3%) showed acute hepatitis and five of them showed cirrhosis. Fatigue and anorexia were the most frequently complained symptoms(55.6%). Four patients(44.4%) were accompanied with other autoimmune diseases. Antinuclear antibody was detected in 5(55.6%) and anti-smooth muscle antibody was detected in 7(77.8%). Three patients showed focal picemeal necrosis and four showed periportal fibrosis. Among 7 patients who received immunosuppressive therapy, six patients(85.7%) showed initial response. and biochemical and serologic remission were achived in 5(71.4%) and 3(42.8%) patients, AIH seems to be partly responsible for chronic liver disease of unknown etiology in Korea. AIH should be suspected in female patients with unknown chronic liver disease of unknown etiolgy, especially accompanied with other autoimmune disease. The clinical characteristics of AIH may not be quite different from those of Western countries.

Desmodianone H and uncinanone B, potential tyrosinase inhibitors obtained from Lespedeza maximowiczii by using bioactivity-guided isolation.

Heo, Do Yeon,Kim, Young Mi,Lee, Joongku,Park, Sang-Hong,Kim, Jinki,Park, Hye Min,Lee, Choong Hwan Japan Society for Bioscience, Biotechnology, and A 2014 Bioscience, biotechnology, and biochemistry Vol.78 No.6

<P>A new bioactive compound, namely desmodianone H(1), and another known compound uncinanone B(2) were first isolated using bioactivity-guided isolation from the leaves of Lespedeza maximowiczii and structures were elucidated by comprehensive analysis of their nuclear magnetic resonance and mass spectrometry data. Compounds 1 and 2 exhibited strong inhibitory effects on mushroom tyrosinase activity.</P>

Potential Induction of Quinone Reductase Activity of Natural Products in Cultured Murine Hepa1c1c7 Cells

Heo, Yeon Hoi,Lee, Sang Kook 梨花女子大學校 藥學硏究所 2001 藥學硏究論文集 Vol.- No.10

NAD(P)H:quinone reductase(QR), known as DT-diaphorase, is a kind of detoxifying phaseⅡ metabolic enzyme catalyzing hydroquinone formatin by two electron reduction pathway from quinone type compounds, and thus facilitatin excretion of quinoids from human body. With the usefulness of QR induction activity assay system for the modulation of toxicants, in the course of searching for cancer chemopreventive agents from natural products, the methanolic extracts of approximately two hundreds of oriental medicines were primarily evaluated using the induction potential of quinone reductase(QR) activity in cultured murine Hepaicic7 cells. As a result, several extracts including Hordeum vulgare, Momordica cochinchinensis, Strychnos ignatii, Houttuynia cordata, and Polygala japonica were found to significantly induce QR activity. In addition, the methylene chloride fraction of H. vulgare, one major dietary food source, showed potent induction of QR acivity(CD=6.4㎍/ml). Further study for isolation of active principles from these lead extracts is warranted for the discovery of novel cancer chemopreventive agents.

Role of Additives on the Performance of CsPbI₃ Solar Cells

Heo, Do Yeon,Han, Sang Mok,Woo, Nam Sub,Kim, Young Ju,Kim, Tae-Yoon,Luo, Zhengtang,Kim, Soo Young American Chemical Society 2018 The Journal of Physical Chemistry Part C Vol.122 No.28

<P>The role of additives in the performance of CsPbI<SUB>3</SUB> perovskite solar cells (PSCs) was investigated. Different kinds of cations and anions were used as additives in a <I>N,N</I>-dimethylformamide (DMF) solution containing CsI and PbI<SUB>2</SUB> (1:1 molar ratio). These include HI, HBr, HCl, NH<SUB>4</SUB>I, NH<SUB>4</SUB>Br, and NH<SUB>4</SUB>Cl. Additive cations (H<SUP>+</SUP> and NH<SUB>4</SUB><SUP>+</SUP>) as well as halide ions (I<SUP>-</SUP>, Br<SUP>-</SUP>, and Cl<SUP>-</SUP>) are important for the properties of PSCs. Especially, the addition of iodine ion showed good characteristics compared to Br<SUP>-</SUP> and Cl<SUP>-</SUP>. Among the CsPbI<SUB>3</SUB> layers prepared with different kinds of additives and annealed at different temperatures, the X-ray diffraction peaks of CsPbI<SUB>3</SUB> were clearly found at 14° and 28° for the sample annealed at 150 °C with 50 μL of HI, suggesting the formation of a cubic structure at the low temperature of 150 °C. The field emission scanning electron microscopy images indicate that the surface of the perovskite layer with hydrogen halide additive (“H<SUP>+”</SUP>-based additive) is more uniform than that with ammonium additive. The roughness profiles determined by atomic force microscopy indicate that the CsPbI<SUB>3</SUB> film with HI additive shows the least roughness among the samples with H<SUP>+</SUP>-based additives. Therefore, the best power conversion efficiency (PCE) of 4.72% is obtained for CsPbI<SUB>3</SUB> PSCs annealed at 150 °C with HI (50 μL). The H<SUP>+</SUP>-based additives seem to react with PbI<SUB>2</SUB> in DMF solution, increasing the solubility of PbI<SUB>2</SUB> and thus lowering the processing temperature. Furthermore, the PCE of CH<SUB>3</SUB>NH<SUB>3</SUB>PbI<SUB>3-<I>x</I></SUB>Cl<SUB><I>x</I></SUB> PSCs decreased from 7.45 to 0.23%, whereas that of CsPbI<SUB>3</SUB> PSCs with 50 μL of HI only decreased from 3.55 to 2.78% after exposing the samples to air for 3 h. These results indicate that H<SUP>+</SUP>-based additives, especially HI, have more impact on the CsPbI<SUB>3</SUB> PSCs in terms of lowering the processing temperature and improving the performance.</P> [FIG OMISSION]</BR>

Bifunctional Moth-Eye Nanopatterned Dye-Sensitized Solar Cells: Light-Harvesting and Self-Cleaning Effects

Heo, Sung Yeon,Koh, Jong Kwan,Kang, Gumin,Ahn, Sung Hoon,Chi, Won Seok,Kim, Kyoungsik,Kim, Jong Hak Wiley Blackwell (John Wiley Sons) 2014 ADVANCED ENERGY MATERIALS Vol.4 No.3

Xylan Hydrolysis by Treatment with Endoxylanase and β-Xylosidase Expressed in Yeast

( Heo Sun Yeon ),( Joong Kyun Kim ),( Young Man Kim ),( Soo Wan Nam ) 한국미생물생명공학회 2004 Journal of microbiology and biotechnology Vol.14 No.1

Opotogenetic brain stimulation neuromodulation system through a Magneto-Mechanical Triboelectric Nanogenerator based on a flashlight annealing process

Yeon Uk kim(김연욱),Yu Mi Woo(우유미),Ui Yeon Nam(남의연),Yun Sik Hwang(황윤식),Jae Chan Heo(허재찬),Jung Hwan Park(박정환) 대한기계학회 2022 대한기계학회 춘추학술대회 Vol.2022 No.11

Growth Inhibition and G2/M Phase Cell Cycle Arrest by 3,4,5-Trimethoxy-4`-bromo-cis-stilbene in Human Colon Cancer Cells

( Yeon Hoi Heo ),( Hye Young Min ),( Sang Hee Kim ),( Sang Kook Lee ) 한국응용약물학회 2007 Biomolecules & Therapeutics(구 응용약물학회지) Vol.15 No.2

Resveratrol (3,5,4`-trihydroxy-trans-stilbene), a naturally occurring phytoallexin abundant in grapes and several plants, has been shown to be active in inhibiting proliferation and inducing apoptosis in several human cancer cell lines. On the line of the biological activity of resveratrol, a variety of resveratrol analogs were synthesized and evaluated for their growth inhibitory effects against several human cancer cell lines. In the present study, we found that one of the resveratrol analogs, 3,4,5-trimethoxy-4`-bromo-cis-stilbene, markedly suppressed human colon cancer cell proliferation (EC50 = 0.01 ㎍/ml), and the inhibitory activity was superior to its corresponding trans-isomer (EC50 = 1.6 ㎍/ml) and resveratrol (EC50 = 18.7 ㎍/ml). Prompted by the strong growth inhibitory activity in cultured human colon cancer cells (Col2), we investigated its mechanism of action. 3,4,5-Trimethoxy-4`-bromo-cis-stilbene induced arrest of cell cycle progression at G2/M phase and increased at sub-G1 phase DNA contents of the cell cycle in a time- and dose-dependent manner. Colony formation was also inhibited in a dose-dependent manner, indicating the inhibitory activity of the compound on cell proliferation. Moreover, the morphological changes and condensation of the cellular DNA by the treatment of the compound were well correlated with the induction of apoptosis. These data suggest the potential of 3,4,5-trimethoxy-4`-bromo-cis-stilbene might serve as a cancer chemotherapeutic or chemopreventive agent by virtue of arresting the cell cycle and inducing apoptosis for the human colon cancer cells.