• 제목/요약/키워드: precision control

검색결과 4,590건 처리시간 0.038초

Fabrication and characterization of $WSi_2$ nanocrystals memory device with $SiO_2$ / $HfO_2$ / $Al_2O_3$ tunnel layer

  • Lee, Hyo-Jun;Lee, Dong-Uk;Kim, Eun-Kyu;Son, Jung-Woo;Cho, Won-Ju
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.134-134
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    • 2011
  • High-k dielectric materials such as $HfO_2$, $ZrO_2$ and $Al_2O_3$ increase gate capacitance and reduce gate leakage current in MOSFET structures. This behavior suggests that high-k materials will be promise candidates to substitute as a tunnel barrier. Furthermore, stack structure of low-k and high-k tunnel barrier named variable oxide thickness (VARIOT) is more efficient.[1] In this study, we fabricated the $WSi_2$ nanocrystals nonvolatile memory device with $SiO_2/HfO_2/Al_2O_3$ tunnel layer. The $WSi_2$ nano-floating gate capacitors were fabricated on p-type Si (100) wafers. After wafer cleaning, the phosphorus in-situ doped poly-Si layer with a thickness of 100 nm was deposited on isolated active region to confine source and drain. Then, on the gate region defined by using reactive ion etching, the barrier engineered multi-stack tunnel layers of $SiO_2/HfO_2/Al_2O_3$ (2 nm/1 nm/3 nm) were deposited the gate region on Si substrate by using atomic layer deposition. To fabricate $WSi_2$ nanocrystals, the ultrathin $WSi_2$ film with a thickness of 3-4 nm was deposited on the multi-stack tunnel layer by using direct current magnetron sputtering system [2]. Subsequently, the first post annealing process was carried out at $900^{\circ}C$ for 1 min by using rapid thermal annealing system in nitrogen gas ambient. The 15-nm-thick $SiO_2$ control layer was deposited by using ultra-high vacuum magnetron sputtering. For $SiO_2$ layer density, the second post annealing process was carried out at $900^{\circ}C$ for 30 seconds by using rapid thermal annealing system in nitrogen gas ambient. The aluminum gate electrodes of 200-nm thickness were formed by thermal evaporation. The electrical properties of devices were measured by using a HP 4156A precision semiconductor parameter analyzer with HP 41501A pulse generator, an Agillent 81104A 80MHz pulse/pattern generator and an Agillent E5250A low leakage switch mainframe. We will discuss the electrical properties for application next generation non-volatile memory device.

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상이한 피크파장의 적색광 및 청색광 발광다이오드 조사에 따른 상추의 생장 및 안토시아닌 (Growth and Anthocyanins of Lettuce Grown under Red or Blue Light-emitting Diodes with Distinct Peak Wavelength)

  • 이재수;김용현
    • 원예과학기술지
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    • 제32권3호
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    • pp.330-339
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    • 2014
  • 430-470nm의 청색광 영역과 630-670nm의 적색광 영역을 5nm 간격으로 세분화한 LED를 인공광원으로 사용하고, 냉백색형광등을 대조구로 사용한 가운데 적치마상추(Lactuca sativa L. '중생종', 흥농씨앗)의 생장 및 안토시아닌 함량에 미치는 적색광 또는 청색광 LED의 피크파장에 따른 광질조사 효과를 분석하였다. 페쇄형 시스템 내에서 생장된 상추의 재배조건은 광주기 16/8h, 기온 $22/18^{\circ}C$, 습도 70%, $CO_2$ 농도 $400{\mu}mol{\cdot}mol^{-1}$로 설정하였고, 베드 면에서의 PPF를 $201{\pm}2\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$로 조절하였다. 정식 후 21일째에 측정된 상추의 생장 특성과 안토시아닌 함량은 청색광 또는 적색광 LED의 피크파장에 따라 유의차가 다르게 나타났다. 본 연구에서 처리된 LED의 피크파장 가운데 R1 처리구(피크파장 634nm)와 R6 처리구(피크파장 659nm)가 엽폭, 엽면적, 지상부 생체중 및 광합성속도의 증가에 효과적이었다. 한편 안토시아닌의 축적에 B5 처리구(피크파장 450nm)가 효과적이었다. 상추 잎의 안토시아닌 함량은 엽색의 hue 값이 작아지거나, 또는 SPAD 값이 커질수록 직선적인 관계를 이루면서 증가하였다. 결론적으로 본 연구에서 얻어진 피크파장 634nm와 659nm의 적색광, 450nm의 청색광은 엽채류의 생산량 증대와 안토시아닌 함량의 증진에 필요한 광질로서 활용될 것이다.

Bar 타겟을 이용한 DMC 영상의 공간해상력 검증 (Verification of Spatial Resolution in DMC Imagery using Bar Target)

  • 이태윤;이재원;윤부열
    • 한국측량학회지
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    • 제30권5호
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    • pp.485-492
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    • 2012
  • 최근 디지털 항공영상 센서는 다양한 국가 공간정보기반구축에 큰 역할을 하고 있다. 하지만 고정밀의 신뢰성 있는 자료를 확보하기 위해서는 취득된 디지털영상에 대한 적절한 품질 평가 작업이 선행되어야 한다. 따라서 현재 관련분야의 연구가 국내외적으로 크게 주목을 받고 있다. 디지털카메라의 성능을 테스트하기 위한 영상해상력 검증용 테스트필드가 유럽과 미국 등에서 이미 설치 및 활용되고 있다. 이러한 테스트필드에는 카메라의 기하학적 성능분석을 위한 대공표지를 비롯하여 공간해상력 및 방사해상력 분석을 위한 다양한 형태의 타겟 역시 설치되어 있다. 본 연구에서는DMC 카메라의 공간해상력을 검증하기 위하여 영상에서 인식 가능한 크기의 바 타겟(bar target)을 제작 설치 후 항공촬영을 수행하였다. 연구에 사용된 DMC 영상의 이론적인 지상표본거리(GSD ; Ground Sample Distance)는 12cm 급으로, 촬영 비행방향과 비행방향의 직각방향에 대하여 보조영상과 집성영상에 대하여 각각 실제 해상력을 분석하였다. 연구결과 이론적인 해상력과 영상의 실제 해상력간의 차이는 약 0.6cm로 나타났으며, 블록의 가장자리에 위치한 영상에서 최대 1.5cm 정도로 나타났다.

Validated HPLC Method for the Pharmacokinetic Study of Atenolol and Chlorthalidone Combination Therapy in Korean Subjects

  • Kang, Hyun-Ah;Kim, Hwan-Ho;Kim, Se-Mi;Yoon, Hwa;Cho, Hea-Young;Oh, Seaung-Youl;Choi, Hoo-Kyun;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • 제36권5호
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    • pp.331-338
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    • 2006
  • A rapid, selective and sensitive reverse-phase HPLC methods for the determination of atenolol and chlorthalidone in human serum and whole blood were validated, and applied to the pharmacokinetic study of atenolol and chlorthalidone combination therapy. Atenolol and an internal standard, pindolol, were extracted from human serum by liquid-liquid extraction, and analyzed on a $\mu$-Bondapak C18 $10-{\mu}$ column in a mobile phase of methanol-0.01 M potassium dihydrogenphosphate(30:70, v/v, adjusted to pH 3.5) and fluorescence detection(emission: 300 nm, excitation: 224 nm). Chlorthalidone and an internal standard, probenecid, were extracted form human whole blood by liquid-liquid extraction, and analyzed on a Luna C18 $5-{\mu}$ column in a mobile phase of acetonitrile containing 77% 0.01 M sodium acetate and UV detection at 214 nm. These analysis were performed at three different laboratories using the same quality control(QC) samples. The chromatograms showed good resolution, sensitivity, and no interference by human serum and whole blood, respectively. The methods showed linear responses over a concentration range of 10-1,000 ng/mL for atenolol and 0.05-20 ${\mu}g/mL$ for chlorthalidone, with correlation coefficients of greater than 0.999 at all the three laboratories. Intra- and inter-day assay precision and accuracy fulfilled international requirements. Stability studies(freeze-thaw, short-, long-term, extracted sample and stock solution) showed that atenolol and chlorthalidone were stable. The lower limit of quantitation of atenolol and chlorthalidone were 10 ng/mL and 0.05 ${\mu}g/mL$, respectively, which was sensitive enough for pharmacokinetic studies. These methods were applied to the pharmacokinetic study of atenolol and chlorthalidone in human volunteers following a single oral administration of Hyundai $Tenoretic^{\circledR}$ tablet(atenolol 50 mg and chlorthalidone 12.5 mg) at three different laboratories.

MEPS-GC/MS를 이용한 농약류 동시 수질분석 (Simultaneous Determination of Pesticides in Water Using a GC/MS Coupled with Micro Extraction by Packed Sorbent)

  • 이기창;이원태
    • 대한환경공학회지
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    • 제37권5호
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    • pp.262-268
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    • 2015
  • 본 연구는 on-line micro extraction by packed sorbent (on-line MEPS)와 시료다량주입장치인 programmed temperature vaporizer (PTV) injector를 결합한 가스크로마토그래피 질량분석 시스템을 이용하여 유기인계 농약인 methyldemetone-S, diazinon, fenitrothion, parathion, phentoate, O-ethyl O-(4-nitrophenyl) phenylphosphonothioate (EPN)과 카바이트계인 carbaryl에 대한 동시 수질분석법을 확립하였다. MEPS 내 sorbent는 polystyrene divinylbenzene (PDVB) 재질을 이용하였다. 시료전처리시 추출용매 종류, pH, 추출용매량 및 시료주입왕복횟수가 분석에 미치는 영향과 정도보증(QA/QC), 그리고 환경시료에 대한 각 물질의 회수율을 평가하였다. 추출용매는 acetone과 dichloromethane을 80 : 20 (v/v)으로 혼합하여 사용하였고, 내부표준물질과 황산을 첨가한 시료 1 mL를 대상으로 추출용매량 $30{\mu}L$, 시료주입왕복횟수를 7회로 추출하여 분석조건을 최적화하였다. pH가 낮을수록 Diazinon의 분석감응도는 감소한 반면 carbaryl의 분석감응도는 증가하였다. 정도보증결과 항목별 방법검출한계 및 정량한계는 각각 $0.02{\sim}0.18{\mu}g/L$, $0.08{\sim}0.59{\mu}g/L$로 낮았으며, 농도범위 $0.5{\sim}5.0{\mu}g/L$ 수준에서 정밀도와 정확도 범위는 각각 1.5~11.5%, 83.3~129.8%로 나타났다. 환경시료 중 carbaryl을 제외한 모든 항목의 회수율은 75.7~129.3%로 적합하였다. Carbaryl에 대한 회수율은 수돗물, 지하수, 하천수 분석에서 적합한 범위를 나타냈으나, 하수처리방류수에서는 200% 이상으로 만족하지 못하였다.

신바로 약침의 한약재 확인시험 및 HPLC-DAD를 통한 표준화 연구 (A Study on Standardization of Shinbaro Pharmacopuncture Using Herbal Medicines Identification Test and HPLC-DAD)

  • 이진호;김민정;이재웅;김미령;이인희;김은지
    • Journal of Acupuncture Research
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    • 제32권2호
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    • pp.1-9
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    • 2015
  • Objectives : The present study was an evaluation and standardization of herbal components in order to establish the efficacy and safety of Shinbaro pharmacopuncture. Methods : Among the raw materials of Shinbaro pharmacopuncture, the components Cibotii Rhizoma, Eucommiae Cortex, and Ledebouriellae Radix were assessed through ingredient verification experiments using thin-layer chromatography(TLC) and ultraviolet rays(UV) lamps. In addition, we standardized Acanthopanacis Cortex and Achyranthis Radix through validation using high performance liquid chromatograph-diode array detector(HPLC-DAD). Results : As result appeared a blue-white fluorescence under ultraviolet rays; changed to dark green after adding 1 % ferric chloride solution(due to Cibotii Rhizoma), and presented a yellow-green fluorescence when mixed with an ethyl ether under UV lamps by way of the ethyl ether layer, confirming Eucommiae Cortex. Ledebouriellae Radix was confirmed as dark brown spots at Rf values of 0.56 and 0.71 using TLC. Additionally, Acanthopanacis Cortex and Achyranthis Radix HPLC test results showed that linearity was $R^2{\geq}0.99$, and detection limit and quantitation limit were 0.23 to $1.29{\mu}g/mL$, and 0.71 to $3.90{\mu}g/mL$, respectively. Furthermore, precision and accuracy were confirmed to have relative standard deviation(RSD) values of 0.10 to 1.89 % and 96.19 to 103.72 %, respectively. Shinbaro pharmacopuncture did not have any overlapping or interference from other peaks in detection under the abovementioned analysis conditions. Conclusions : In conclusion, we confirmed that maintenance of Shinbaro pharmacopuncture validity was possible by means of quality control of Cibotii Rhizoma, Eucommiae Cortex, and Ledebouriellae Radix through ingredient identification and Acanthopanacis Cortex and Achyranthis Radix through high performance liquid chromatograph(HPLC) analysis. Further, we hope to contribute to the development strategy of herbal industry acupuncture.

타이어 공기압 시스템 기술을 사용한 차량의 적재중량 측정 시스템 개발 (Development of a Load Measurement System for Vehicles using Tire Pressure System Technology)

  • 박제현;이승호
    • 전기전자학회논문지
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    • 제24권1호
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    • pp.33-39
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    • 2020
  • 본 논문에서는 타이어의 물리적인 요소 중 하나인 압력정보를 이용해서 자동차의 하중 표출이 가능한 타이어 공기압 측정 기술을 사용한 차량의 적재중량 측정시스템 설계 기법을 제안한다. 제안된 기법은 하중 및 진동에 의한 노이즈 보정, 기체유량 보정, 데이터 믹서, 중량 환산 등의 4가지 과정으로 구성된다. 하중 및 진동에 의한 노이즈 보정에서는 외부충격 및 차량이 주행 중 발생하는 진동 등에 의해 타이어의 내부 압력이 상승하는 노이즈를 제거한다. 기체유량 보정 과정에서는 하중 및 진동에 의한 노이즈 보정 과정을 거친 데이터에 대하여 지면의 온도상승에 의해 타이어의 내부 압력이 상승하는 노이즈를 제거한다. 데이터 믹서 과정에서는 화물적재 시 타이어에 수직으로 전달이 되어 타이어의 압력변화에 따른 공차, 중차, 만차에 대한 하중과 압력 등을 분류하게 된다. 중량 환산 과정에서는 하중 및 진동에 의한 노이즈 보정 및 기체유량 보정을 거친 데이터를 사용하여 중량 환산 알고리즘을 통해 중량으로 표출된다. 중량 환산 알고리즘은 하중과 압력변화에 대한 선형 함수의 기울기인 중량 환산 Factor를 구하여 중량을 환산한다. 본 논문에서 제안된 타이어 공기압 측정 기술을 사용한 차량의 적재중량 측정 시스템의 정밀도를 평가하기 위해 자체적으로 테스트 베드를 구축하여 평가하였다. 하중 및 진동에 의한 노이즈 보정 결과와 기체 유량 데이터 보정 결과는 신뢰성 있는 결과를 나타내었다. 또한 중량 정밀도 반복 실험도 국내 업체 기준치인 90% 보다 우수한 중량 정밀도를 나타내었다.

고시 수재 의약품 중 피라세탐 정 및 브롬화수소산페노테롤 정의 용출시험법 개발 (Development of Dissolution Testing Method for Piracetam Tablets and Fenoterol Hydrobromide Tablets in Korean Pharmaceutical Codex)

  • 김은정;이진하;박찬호;손경희;김인규;김동섭;사홍기;최후균
    • 약학회지
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    • 제55권4호
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    • pp.324-331
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    • 2011
  • Although the dissolution test can serve as an effective tool for quality control and predictor of in vivo performance, there are a number of drugs with no established dissolution specifications in Korean Pharmaceutical Codex (KPC). Among those commercially available, Piracetam Tablets and Fenoterol hydrobromide Tablets were selected to develop the dissolution testing method. The dissolution condition was determined based on the "Guidelines on Specifications of Dissolution tests for Oral dosage forms" of Korea Food & Drug Administration (KFDA). The dissolution test for Piracetam Tablets was carried out under sink condition with distilled water as dissolution medium, paddle rotation speed at 50 rpm and medium volume of 900 ml. More than 80% of its label claim was released within 30 min. In case of Fenoterol hydrobromide Tablets, distilled water was also found to be suitable to ensure sink condition. The rotation speed of 50 rpm and 900 ml of dissolution medium were used to evaluate the dissolution profile. The dissolution rate of fenoterol hydrobromide was over 90% in 15 min. The HPLC analysis methods were validated in terms of accuracy, precision, specificity, linearity, quantitation limit and range. The results suggested that the analytical methods used are simple and suitable to measure the dissolution rate of piracetam and fenoterol hydrobromide. Therefore, the analysis methods could be utilized in setting dissolution specifications of Piracetam Tablets and Fenoterol hydrobromide Tablets in the revised version of KPC.

생물학적제제의 치메로살 함량 정량을 위한 가열기화 아말감 흡광도법의 확립 및 검증 (Establishment and Validation of Gold Amalgamation Method for the Quantitation of Thimerosal in Biological Products)

  • 김병철;김도근;홍성화;김연희;임종미;원윤정;김석환;홍지영;윤영민;김재옥
    • 약학회지
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    • 제55권4호
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    • pp.284-288
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    • 2011
  • The test method for biologics of lot release system is based on 'Test procedure and specification for biological products,' generally, thimerosal content is measured by chemical analysis using O.D. In this study, the comparative analysis was carried out using the gold amalgamation method for thimerosal content was compared to the existing methods, which are described above. The gold amalgamation method, which uses atomic absorption spectrophotometry, was meets all the method validation acceptance criteria. It is considered to be proper as the assay and identification test for thimerosal. In this study, the comparative analysis was performed three times. As a result, gold amalgamation method is more convenient and easy to perform as this assay doesn't have pre-treatment procedure. Also this assay showed good precision and reproducibility compared to the conventional method. Therefore, it is appropriate to alternate the assay method of thimerosal from the conventional chemical analysis to gold amalgamation method to improve the credibility of lot release system and the quality control of biologics, by standardizing test method.

태양전지 모듈의 발전량 분석 장치 개발에 관한 연구 (A Study on Development of Power Analysing Device for PV Module)

  • 문채주;곽승훈;장영학;김태곤;김의선;김태현
    • 한국태양에너지학회 논문집
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    • 제30권6호
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    • pp.73-80
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    • 2010
  • This study was conducted to estimate the relative performance of modules with changed characteristics due to long term exposure to the outdoor environment, with a specially made test device for simultaneous measurement of real time power output from the photovoltaic array, taking into account the inclined panel, direct irradiation, power being generated, temperature as well as the optimal analysis timing. In terminology description, M is an abbreviation of module and Group A, Group B are 10 modules series connection (1~10 of M), (11~20 of M) for each of them respectively. The overall mean voltage difference of M-18 with the lowest power output and M-14 with the highest output is-2.13V and it was identifiable that voltage difference was more concentrated to Group B. In addition, in case of M-2 and M-7, M-8, when compared with M-14, the overall mean voltage difference was -0.92V, -1.56 and -0.91V respectively showing the more concentration to Group A. When the temperature of module went up by $1^{\circ}C$, the mean voltage was reduced by 0.35V. For current, Group A was lower than Group B by-0.022A and the ratio of each group was 49.68% and 50.32% respectively, presumably the module with deteriorated properties were more concentrated to Group A relatively. From the comparison of relations with the comprehensive accumulation, M-2, M-7, M-8, M-16 and M-18 were those with deterioration of performance to the worst, thereby requiring precision examination. In comparative efficiency, M-14 was the most excellent one as 12.19% while M-18 as 10.53% was identified that its efficiency was comparatively rapidly reduced.