Nanogenerators: Fully Rollable Transparent Nanogenerators Based on Graphene Electrodes (Adv. Mater. 19/2010)

Choi, Dukhyun,Choi, Min-Yeol,Choi, Won Mook,Shin, Hyeon-Jin,Park, Hyun-Kyu,Seo, Ju-Seok,Park, Jongbong,Yoon, Seon-Mi,Chae, Seung Jin,Lee, Young Hee,Kim, Sang-Woo,Choi, Jae-Young,Lee, Sang Yoon,Kim, Jo WILEY-VCH Verlag 2010 ADVANCED MATERIALS Vol.22 No.19

<B>Graphic Abstract</B> <P>The cover shows an image of fully rollable transparent nanogenerators synthesized using chemical vapor deposition grown large-scale graphene sheets as transparent electrodes and piezoelectric ZnO nanorod arrays. Sang-Woo Kim, Jae-Young Choi, and co-workers report on p. 2187 the electrical and structural stability of the nanogenerators, with excellent charge scavenging performance under external mechanical loads such as bending and rolling. This study shows that graphene-based nanogenerators are very promising for self-powered rollable transparent device applications. <img src='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content.gif' alt='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content'> </P>

국내 혈액질환 환자에서 침습성 아스페르길루스증의 구제치료로서 Voriconazole의 효과와 안전성

권재철,김시현,최수미,최재기,이동건,박선희,최정현,유진홍,신완식 대한감염학회 2010 감염과 화학요법 Vol.42 No.1

Background: Invasive aspergillosis (IA) is associated with significant morbidity and mortality in patients with hematologic malignancies. We investigated the efficacy and safety of voriconazole (VCZ) when used as salvage therapy for IA in Korean adults with hematologic malignancies who had not responded to prior antifungal therapy. Materials and Methods: We retrospectively reviewed data, collected from January 2007 to October 2008, from patients with proven or probable cases of IA. All were probable IA cases, except for one proven case. All cases were refractory or intolerant to antifungal therapy prior to administration of VCZ. Efficacy and safety were assessed in patients treated with VCZ for more than 3 days and for more than one dose, respectively. A favorable response [complete (CR) or partial (PR)] was defined by significant improvement of all clinical symptoms, signs, and radiologic abnormalities. Results: Fifty patients who met the inclusion criteria were enrolled. There were 27 male and 23 female patients with mean age of 44.4 years (range, 15-65 years). Underlying diseases were acute leukemia (35 cases), chronic myelogenous leukemia (4 cases), myelodysplastic syndrome (3 cases), lymphoma (3 cases) and other hematologic diseases (5 cases). Twenty-two patients had received chemotherapy and 13 patients had undergone hematopoietic stem cell transplantation. The lung was the main infection site (94%) followed by the sinus (6%). Amphotericin B deoxycholate alone was the most frequent previous antifungal therapy. The mean duration of antifungal therapy prior to VCZ therapy was 13.9±8.8 days (2-44 days). The median duration of VCZ therapy was 19 days (interquartile range, 49 days). Sixteen patients (32.0%) showed favorable responses (CR:PR=8:8) at the end of VCZ therapy. The numbers of patients with stable disease, progression and death were, 6 (12%), 6 (12%) and 22 (44%) respectively. Most of those with unfavorable responses had relapsed underlying malignancies or refractory graft versus host diseases. Twelve patients developed drug-related adverse events but only one patient stopped VCZ treatment prematurely. Conclusions: VCZ demonstrated an acceptable level of toxicity in patients with hematologic malignancies but further studies are required to prove its efficacy as salvage therapy.

Photonic Crystals: Integration of Colloidal Photonic Crystals toward Miniaturized Spectrometers (Adv. Mater. 9/2010)

Kim, Shin-Hyun,Park, Hyo Sung,Choi, Jae Hoon,Shim, Jae Won,Yang, Seung-Man WILEY-VCH Verlag 2010 Advanced materials Vol.22 No.9

<B>Graphic Abstract</B> <P>The cover shows a schematic illustration of patterned colloidal photonic crystals with different bandgap positions. When an unknown light source impinges on the patterned photonic crystals, the light information can be identified from the reflection intensity profile of the constituent photonic crystals. The two optical microscopy images and background image display integrated photonic crystals with 20 different bandgaps spanning the entire visible range, and the SEM image shows the cross-section of the photonic crystal stripes, as reported by Shin-Hyun Kim, Seung-Man Yang, and co-workers on p. 946. <img src='wiley_img_2010/09359648-2010-22-9-ADMA201090022-content.gif' alt='wiley_img_2010/09359648-2010-22-9-ADMA201090022-content'> </P>

冷間押出用 헬리컬기어 金型의 强度解析

崔載燦,權赫洪,辛榮柱 부산대학교 공과대학 1992 工大論文集 Vol.44 No.-

In forging die design, pre-stressing is useful in preventing excessive tensile circumferential stresses which may cause die failure during forming. The finite element analysis (F.E.A.) package ANSYS reversion 4.4 A was used to this study. F.E.A., that is, static analysis was accomplished for insert-dies of helical gear. Die model was constructed with 8 node isoparametric solid finite elements. Static load analysis was performed for internal and outer pressure. Also, stress distribution and deformed shapes are shown. To assure durability and reliability, failure analysis was calculated by maximum normal stress theory and distortion energy theory. Results of the F.E. analysis and failure analysis for Samanta and new process dies were compared. The results of F.E. Analysis were in good agreement with that of experimental results. It is expected that the results of this study can be applied to designing various kinds of extrusion gear die.

기하광학영역에서의 능동소나 표적신호합성

신기철,박재은,김재수,최상문,김우식 한국해양대학교 해양과학기술연구소 2001 硏究論文集 Vol.10 No.1

능동소나 시스템에서 표적신호의 근거리 정보가 중요해짐에 따라, 표적 음향산란 신호의 고유한특성을 분석하기 위해 실험적인 방법과 시뮬레이션 기법이 사용된다. 본 논문에서는 표적신호 합성을 위해 축소표적 반향실험을 수행하였고, 자료의 분석 결과 축소표적의 음향산란은 거울면 반사의 영향이 큰 것으로 분석되어, 표적신호 합성에서 기하광학이론을 응용하였다. 복잡한 형태의 표적을 여러 표본형상으로 분리하고, 각 표본형상의 기여도를 신호의 위상과 강도를 줌으로써 계산하였으며. 표적신호 합성모델의 검증을 위해 실제 축소표적 실험 결과와 비교하였다. 혁심용어: 기하광학이론. 음향산란, 거울면반사. 축소표적, 능동소나 투고분야: 수중음향 분야 (5.2) Since the near field iformation of target signal is important in the development and verification of active sonar system experimental method and simulation technique are widely used in order to analyze the detail characteristics of target scattered echoes. Therefore, in this paper, the scale target experiment is performed to develope and improve the target signal simulation model. Since the experimental results show that the specular reflection is the major component among scattering mechanisms, the target signal simulation model based on the Geometric Optics Theory (GOT) is developed. Complex target is separated into simple shapes, known as canonical shape. The contribution from individual canonical shapes are summed with proper phase and amplitude to produse the target strength of the whole complex body. Simulated target signal is compared with the experimental results fed discussed.

치과용 실험 레진에서 광 기시제와 중합억제제 함량이 광중합에 주는 영향

신현철,임범순,최재윤,이용근 大韓齒科器材學會 2004 대한치과재료학회지 Vol.31 No.4

The purpose of this study was to evaluate the effect of fraction of photo-initiator and inhibitor in the experimental resins on the degree of polymerization using a FT-IR and dynamic mechanical analyzer (DMA). Eight experimental dental resins, four different concentrations of photo-initiator (EXP-A, EXP-B, EXP-C, EXP-D) and four different concentrations of inhibitor (EXP-E, EXP-F, EXP-G, EXP-H), were tested. Storage modulus was measured by using DMA (StressTech Rheometer, Rheologica Instrument, Sweden) with fast oscillation mode (1 Hz). After disk-typed (4 ㎜×1 ㎜) samples were irradiated with Halogen light curing unit at 500 ㎽/㎠ for 30 sec, the storage modulus was recorded continuously for 60 min. The degree of conversion was also measured using the FT-IR spectroscopy (FTS-165, Biorad Win-IR, Perkin-Elmer, USA) at 1 hr and 24 hrs after irradiation with the same curing condition as DMA test. The average of results for five specimens was analyzed using Tukey multiple comparison test (p=0.05). From the results, the minimum concentration of photo-initiator was 0.35 wt.% and the maximum concentration of inhibitor was 0.15-0.20 wt.% to obtain the proper polymerization. To enhance the biocompatibility, the concentration of photo-initiator should be added to dental resins as low as possible. To prolong the shelf-life, the concentration of inhibitor should be added to dental resins as much as possible, but biocompatibility due to the inhibitor should be considered to determine the optimum concentration.

UV 센서를 위한 Spiroxazine LB 단분자막 특성에 대한 연구

최성욱,박은진,장지훈,김재호,강신원 경북대학교 센서기술연구소 2002 센서技術學術大會論文集 Vol.13 No.1

성인에서 지역 사회 획득 폐렴 (원외 폐렴) 치료를 위한 항생제의 사용원칙

신종욱,김재열,박인원,최병휘 중앙대학교 의과대학 의과학연구소 2003 中央醫大誌 Vol.28 No.2-3

각국에서 제시되고 있는 여러 가지 원외 폐렴의 치료 지침은 일부 차이가 있지만 다음과 같은 공통적인 원칙을 정할 수 있다. 1. 모든 입원 환자는 병원도착 8시간 이내에 주사용 항생제를 투여하여야 한다. 2. 치료의 목표가 되는 원인균에는 비전형적 병원균과 폐렴구균을 반드시 포함하는 항생제를 선택하여야 한다. 3. Macrolide 단독 치료는 심폐질환이 없고 약제내성 폐렴구균, 그람음성간균, 흡인의 위험이 없는 원외 폐렴에 시도해볼 수 있으나 작금 국내의 항생제 내성률을 고려하면 실패의 위험이 있다. 4. 약제내성 폐렴구균 (Drug-resistant Streptococcus pneumoniae; DRSP), 그람음성간균에 대한 위험 인자가 있는 외래 환자, 입원 원외 폐렴 환자에 대한 항생제로는 β-lactam/macrolide 병합요법이나 폐렴구균에 항균력이 강한 fluoroquinolone 단독 투여가 추천되면 동일한 효과를 기대할 수 있다. 5. DRSP의 임상적 위험 인자가 있는 원외 폐렴 환자의 외래 치료를 위해서는 β-lactam/macrolide 병합요법이나 폐렴구균에 항균력이 강한 fluoroquinolone 단독 투여가 추천되는데, 가능한 β-lactam 항생제로는 oral cefpodoxime, cefuroxime, high-dose amoxicillin, amoxicillin/calvuanate, pareneteral ceftriaxone followed by oral cefpodoxime 등이 포함된다. 6. DRSP위험 입원 환자에 대해서는 폐렴구균에 항균력이 있는 guinolone의 정맥 투여 또는 특정 β-lactam과 macrolide의 병합요법이 추천된다. 이 때 가능한 β-lactam 항생제로는 cefotaxime, ceftriaxone, ampicillin/sulbactam, high-dose ampicillin이다. 7. 항녹농균 항생제는 녹농균 감염의 위험이 확인된 중증의 원외 폐렴 환자에게만 제한적으로 투여되어야 한다. 항녹농균성 β-lactam은 이러한 위험 인자를 가진 환자에게만 선택적으로 경험 치료로서 투여하여야 한다. 8. Vancomycin은 중증의 원외 폐렴 환자이거나 수막염이 동반된 원외 폐렴일 경우에만 경험적 치료에 선택되어야 한다. 9. 폐렴구균에 항균력이 있는 quinolone제재들은 체외 감수성 검사에서 서로 다른 항폐렴 구균능을 갖고 잇다. 최소로부터 최고 순으로 나열하면 levofloxacin, gatifloxacin, moxifloxacin 순서이며 가장 항균력이 강한 약제가 내성을 유발할 가능성이 가장 낮다. 10. 사망률을 증가시킬 것으로 예상되는 임상적 의미를 갖는 폐렴구균의 penicillin 내성은 penicillin MIC가 4g/㎖ 이상일 때이다. Community-Acquired Pneumonia (CAP) is still one of the leading causes of major morbidity and mortality of infectious diseases in immunocompetent hosts. Although antibiotics are mainstay of treatment for CAP, a definite guideline remains to be uncertain. This uncertainty currently forces physician out to make therapeutic challenge with modest danger. So we intend to prepare a guideline for antibiotic usage for CAP. Most causative etiologies contain Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, Chlamydia pneurnoniae, Legionella pneumophila. Antibiotics should be administered to cover all these organisms when a definitive etiologic microorganism are not determined. Except for aspiration pneumonia, one pneumonia usually has one causative agent. Drug-resistant Streptococcus pneumoniae and Haemophilus influenzae should be considered for antibiotic choice. Severity of CAP depends on cardiopulmonary physiologic status, age and comorbid conditions. In this regard, fluoroquinolones and β -lactam antibiotics and macrolides can be successfully administered for the treatment of CAP.

광도 변화가 광중합형 컴포머와 컴포짓트 레진의 중합도 및 불소 유출에 주는 영향

최재윤,이해형,임범순,이용근,신현철 大韓齒科器材學會 2004 대한치과재료학회지 Vol.31 No.4

The purpose of this study was to investigate the fluoride releasing behavior of one self-curing glass-ionomer (Fuji II), one light-curing glass-ionomer (Fuji II LC), three compomers (PrismaFlow, UniFil F, and Dyract AP) and SIX composite resins (Flowline, Fissurit FX, Flow-It, Wave, Heliomolar Flow, and Glacier) as a function of light intensity. Disk type specimens were stored in deionized water at 37℃ for 1, 2, 4, 8 hrs and 1, 2, 7, 14, 21, 28 days. The deionized water was changed after measurements. The amount of fluoride ion, which was released from specimens, was measured by pH/ISE Meter (Istek Model 730P, Korea) with fluoride electrode. The results were statistically compared by Tukey multiple comparisons test (p=0.05). There were significant differences in degree of polymerization between specimens with 1 hr after irradiation and those with 24 hrs after irradiation (p<0.05). The cumulative amount of fluoride released was decreased with increasing light intensity (or degree of polymerization). The fluoride-releasing patterns of specimens were significantly different (p<0.05).

IMT-2000용 수신단 One-chip MMIC의 설계 및 제작

신상문,권태운,최재하 울산대학교 2002 공학연구논문집 Vol.33 No.1

본 논문은 IMT-2000용 수신단 One-chip MMIC의 설계 및 제작에 관한 것이다. LNA, 이중 평형 믹서, LO 발룬, RF 발룬, 그리고 IF 증폭기를 하나의 칩에 집적시켰다. 새롭게 제안된 바이어스 회로는 공정상의 변화와 온도의 변화 등의 원인에 의한 문턱전압의 변화를 보상할 수 있다. 제작된 칩의 측정 결과는 모의실험으로 얻은 결과와 일치하지 않는다. LNA는 변환이득이 평탄하게 동작하지 않을 뿐만 아니라 발진현상도 나타났다. 문제에 대한 분석을 통해 원인을 찾았으며, 이 결과는 향후 연구에 사용하려고 한다. 믹서의 변환손실은 -14㏈, IP3는 4㏈m, 포트간 격리도는 25㏈ 이상인 특성을 나타낸다. 설계된 칩은 ETRI MESFET 0.5 ㎛공정으로 제작하였으며 칩 사이즈는 1.4㎜×1.4㎜이다 This is paper describes a design and fabrication of a one-chip receiver MMIC for IMT-2000. The LNA, double balanced mixer, LO balun, RF balun, IF amplifier and a bias circuit are integrated a chip. Each balun operates active and composed of MESFETs. The new applied bias circuit is able to compensate the variation of the threshold voltage caused by the process variation, temperature changes, and etc. The measured response of the fabricated chip doesn't correspond with the simulated performance, the LNA is not only the conversion gain doesn't operates flatly, but also even the oscillation presented. By the study of the cause about the problem, the factor was found. And the result will be deal with further study. The mixer achieves the conversion losses of -14㏈, IP3 of 4㏈m, and port to port isolation over 25㏈. The designed chip is fabricated by the ETRI MESFET 0.5㎛ process. The chip size is 1.4m×1.4m.