• 제목/요약/키워드: residual time

검색결과 2,071건 처리시간 0.032초

입력성형을 통한 웨이퍼 이송장치의 잔류진동 감쇠 (Reduction of Residual Vibration in Wafer Positioning System Using Input Shaping)

  • 임재철;안태길;조중근
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.559-563
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    • 2005
  • The wafer positioning robot used in the semiconductor industry is required to operate at high speed for the improvement of productivity. However, the residual vibration produced by the high speed of the wafer positioning robot makes the life of the robot shorter and the cycle time longer. In this study, the input shaping and the path of the system are designed for the reduction of the residual vibration and the optimization of the cycle time. The followings are the process for the reduction and the optimization; 1)System modeling of wafer positioning robot, 2)Verification of dynamic characteristic of wafer positioning robot, 3)Input shaping plan using impulse response reiteration, 4)Simulation test using simulink, 6)Analysis of result.

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조리방법에 따른 상용채소의 무기질 함량 변화 -무청, 콩나물, 취나물을 중심으로- (Changes on Mineral Contents of Vegetables by Various Cooking Methods)

  • 한재숙;김정숙;김명선;최영희;일본명;허성미
    • 한국식품조리과학회지
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    • 제15권4호
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    • pp.382-387
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    • 1999
  • This study was conducted to investigate the changes of mineral contents in radish leaves, soybean sprout and chwi namul by cooking method(boiling, steaming, sauting) and cooking time(1, 3, 5 min.). The residual rate of minerals(such as Calcium, Sodium, Potassium, Iron and Magnesium) in radish leaves, soybean sprout and chwi namul by 1 minute sauting was the range of 83.2 to 99.1%. It was shown that sauting was desirable method for all three vegetables. The residual rate by the cooking method was sauting, steaming, boiling, in that order, but boiling in radish leaves and chwi namul were more desirable method than steaming for Calcium use. At the cooking method and cooking time, Potassium content in soybean sprout was reduced remarkably in 5 minutes boiling. Boiling of radish leaves and soybean sprout showed that Sodium was reduced remarkably after 5 minutes of boiling, 54.4% for radish leaves and 19.9% for soybean sprout, respectively.

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전도성 E1 펄스에 대한 ZnO 바리스터의 동작특성 분석 (Response Characteristic Analysis of ZnO Varistors by the Conductive E1 Pulse)

  • 방정주;허창수
    • 한국전기전자재료학회논문지
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    • 제32권3호
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    • pp.241-245
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    • 2019
  • This work presents the response characteristics of a ZnO varistor to conductive EMP. An E1 pulse, standardized to MIL-STD-188-125-1, was applied to the varistors wherein the residual current and response times were measured with the applied E1 pulse current. Additionally, the response time was measured according to the length of the connection path. Consequently, the amplitude of the residual voltage through the ZnO varistors was increased with increasing amplitude of the applied E1 pulse current. As the length of the connection path increased, the operating response time and residual peak voltage also increased. These results indicate that the response characteristics of ZnO varistors can be applied to basic data to support the use of varistors as a protective measure against conductive EMP.

벌꿀중의 잔유항생물질 및 Propionic Acid 분석011 관한 조사연구 (A Study on Analysis of Residual Antibiotics and Prop Acid in Honey)

  • 전상수
    • 환경위생공학
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    • 제5권2호
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    • pp.63-80
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    • 1990
  • A sensitive and simple analytical system for the simultaneous determination of residual oxytetracycline, tetracycline, and doxycycline in honey was described, and that the analytical method for determination of residual propionic acid in honey was established. Experimental subjects were purchased four kinds of honey, native kind honey, acaccia honey, mixed floral honey, chestnut honey in Kyung Sang Nam Do. Several microbiological methods are available to determine tetracycline antibiotecs(TCs) in foods but their precision apears to be variable and the specificity is questionable. These methods are considered to be not suitable for analysis of tetracycline antibiotics in honey because honey itself has bacteriostatic action. For determination of tetracycline antibiotics in honey, therefore the High Performance Liquid Chromatography(HPLC) method was applied, and the propionic acid were determined by Gas Chromatography(5.C). Ethylacetate, as an extract solvent, was found to be suitable for seperation of TCs in honey, but methanol and acetone were not. The recoverly rate of Oxytetracycline(OTC), Tetracycline(TC), Doxycycline(DC) from honey spiked at a level of 10 $\mu $g/g were 97%, 89%, and 91%, respectively. The cailbration curve in TCs was linear expression from 2$\mu $g/ml to 10$\mu $g/ml. As the results of analysis, the residual tetracycline antibiotics were not detected in the 100 samples of honey. The recovery rate of propionic acid from honey spiked at level of 10$\mu $g/g was 98.3% , and the calibra lion curves were linear expression from 21$\mu $g/ml to 101$\mu $g/ml. As the results of analysis, the residual propionic acid was not detected in the 100 samples of honey. Retention time(min) of OTC, DC, and TC were 3.35, 4.61, and 5.30 minutes at the conditions of table 2, respectively, and retention time(min) of propionic acid was 3.50 minutes at the conditions of table 3. The residual TCs and propionic acid were not detected in the 100 samples of honey, but there is a possibility that antibiotics or propionic acid will be to remain in honey if they are used during product period in order to prevent putrefaction of honey-bee.

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OTDM/WDM 전송을 위한 40 Gbps RZ 형식의 최적 조건 도출 (Induction of Optimal Condition of 40 Gbps RZ Format for OTDM/WDM Transmission)

  • 이성렬
    • 한국항행학회논문지
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    • 제14권6호
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    • pp.831-837
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    • 2010
  • 광 시간 분할 다중/파장 분할 다중 (OTDM/WDM; optical time division multiplexing/wavelength division multiplexing) 전송 시스템의 구현을 위한 40 Gbps RZ 형식의 최적 조건을 충격 계수 (duty cycle)와 소광비 (ER; extinction ratio)에 따른 성능 분석과 비교를 통해 도출하였다. 광전송 링크에는 광섬유의 색 분산과 비선형에 의한 신호 왜곡을 보상하기 위해 광 위상 공액기 (OPC; optical phase conjugator)와 inline 분산 제어 (DM; dispersion management)가 적용되었다. ER에 따른 시스템 성능 변화의 영향이 적으면서 동시에 OTDM에 의한 160 Gbps 신호로의 다중화에 적합한 충격 계수는 0.25이라는 것을 확인하였다. 또한 DM의 적용에 있어 중계 거리 당 잉여 분산 (RDPS; residual dispersion per span)을 크게 할수록 동일한 전체 잉여 분산 (NRD; net residual dispersion)에 의해 결정되는 RZ 형식의 성능 개선 정도를 증가시킬 수 있는 것을 알 수 있었다.

현장타설말뚝의 잔류응력 분포에 관한 연구 (A Study on the Distribution of Residual Stress for Drilled Shaft)

  • 김원철;황영철;안창윤
    • 한국지반환경공학회 논문집
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    • 제6권1호
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    • pp.45-51
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    • 2005
  • 말뚝을 설계함에 있어 극한지지력을 산정하는 것만으로는 말뚝의 장기 거동에 있어서의 하중분포를 고려할 수 없으므로 재하시험시 변형률계나 응력계를 사용하여 말뚝의 하중 재하에 따른 주면저항(the shaft resistance)의 분포를 측정하고 있다. 그러나 대부분의 재하시험시 하중이 '0'일 때를 'zero time'으로 하여 계측기의 값을 읽는 'zero reading'을 가정함으로써 현장타설말뚝이나 항타말뚝의 시공시 발생된 잔류응력(the residual stress 또는 the residual load)을 무시하고 있다. 이러한 'zero reading'의 가정은 말뚝 시공시 발생하는 말뚝 하방향으로의 부주면마찰력인 잔류응력을 고려하지 않으므로 실제 말뚝주면의 하중분포와는 다른 결과를 보이게 된다. 본 연구에서는 현장에 시험시공된 현장타설말뚝에 대하여 정재하시험을 수행하였고, 말뚝 주면의 하중분포 측정시 변형률계를 사용하여 콘크리트 타설 직후부터 계측을 실시함으로써 말뚝 시공에 따른 잔류응력을 측정하였다. 그 결과, 잔류응력이 고려된 경우는 초기에 부의 응력상태를 보이나 하중이 재하됨에 따라 부주면마찰력이 극복되면서 양의 주면마찰력으로 전환됨을 알 수 있었으나, 'zero reading'의 경우는 양의 주면마찰력 만을 보였다.

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Friction Stir Welding Analysis Based on Equivalent Strain Method using Neural Networks

  • Kang, Sung-Wook;Jang, Beom-Seon
    • 한국해양공학회지
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    • 제28권5호
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    • pp.452-465
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    • 2014
  • The application of friction stir welding (FSW) technology has been extended to all industries, including shipbuilding. A heat transfer analysis evaluates the weldability of a welded work piece, and elasto-plastic analysis predicts the residual stress and deformation after welding. A thermal elasto-plastic analysis based on the heat transfer analysis results is most frequently used today. However, its application to large objects such as offshore structures and hulls is impractical owing to its long computational time. This paper proposes a new method, namely an equivalent strain method using the inherent strain, to overcome the disadvantages of the extended analysis time. In the present study, a residual stress analysis of FSW was performed using this equivalent strain method. Additionally, in order to reflect the external constraints in FSW, the reaction force was predicted using a neural network, Finally, the approach was verified by comparing the experimental results and thermal elasto-plastic analysis results for the calculated residual stress distribution.

중환자실 경장영양 환자의 영양지원, 위 잔여량 및 영양상태 (Nutritional Support, Gastric Residual Volume and Nutritional Status during Enteral Nutrition in Intensive Care Unit Patients)

  • 이민주;강지연
    • 성인간호학회지
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    • 제26권6호
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    • pp.621-629
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    • 2014
  • Purpose: The purpose of this study was to investigate the nutritional support, gastric residual volume, and nutritional status of the intensive care unit (ICU) patients on enteral feeding. Methods: A descriptive longitudinal design was used to collect 5 day data on enteral nutrition of 52 ICU patients in an university hospital. Nutritional support was calculated with actual caloric intake compared to individual caloric requirement. Residual volumes were measured prior to routine feedings, and the serum albumin levels and the total lymphocyte counts were checked to evaluate nutritional status. The data were analyzed using one group repeated measures ANOVA, paired t-test, and Spearman's bivariate correlation analysis. Results: The subjects received their first enteral feeding on the $5.75^{th}$ day of ICU admission. The mean nutritional support rate was 49.1% of the requirement, however prescription rate and support rate were increased as time goes by. Gastric residual volumes were less than 10 cc in 95% cases. A significant negative correlation was found between nutritional support and nutritional status. Conclusion: The nutritional support for ICU patient was low compared to the requirement, and their nutritional status was worse than at the time of ICU admission. Further studies are necessary to develop nursing interventions for improving nutritional support for ICU patients.

Cadmium Accumulation and Elimination in the Tissues of the Manila Clam, Ruditapes philippinarum, after Sub-chronic Cadmium Exposure

  • Jang, Seok-Woo;Kim, Seong-Gil;Choi, Ok-In;Kim, Seong-Soo;Kang, Ju-Chan
    • Fisheries and Aquatic Sciences
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    • 제12권4호
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    • pp.324-330
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    • 2009
  • Cadmium (Cd) accumulation and elimination were assessed in the tissues of the clam R. philippinarum at four experimental concentrations (control, 10, 20, 100, and $200\;{\mu}g/L$) over an exposure period of 2 weeks and an elimination period of 1 week. Cd accumulated in the digestive gland, gill, and residual clam tissues, and accumulation increased with time of exposure and concentration (100 and $200\;{\mu}g/L$). After 2 weeks of Cd exposure, the order of Cd accumulation in tissues was gill > digestive gland > residual tissues. An inverse relationship was observed between concentration factor (CF) and exposure level, but the CF showed an increase with exposure time. During the depuration period, Cd concentrations in the digestive gland, gill, and residual tissues decreased immediately on the cessation of exposure, except in individuals at the $200\;{\mu}g/L$ concentration. The Cd elimination rate from tissues decreased in the order of digestive gland > gill > residual tissues during the depuration period.

가중된 예측 오차 파라미터를 사용한 화자 확인 성능 개선 (Speaker Verification Performance Improvement Using Weighted Residual Cepstrum)

  • 위진우;강철호
    • 한국음향학회지
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    • 제20권5호
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    • pp.48-53
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    • 2001
  • LPC분석 기반 화자 확인에서 잔여성분(residue) 예측은 보통 무시되고, LPCC(LPC-cepstrum)만이 특징 파라미터로 사용된다. 본 연구에서는 잔여성분으로부터 추출된 예측파라미터인 잔여 켑스트럼(residual cepstrum)을 LPCC와 함께 여러 환경에서 구축된 데이터 베이스에서 화자특징 파라미터로 사용하였다. 또한, 잔여 켑스트럼에 포함되어있는 화자 고유성분인 피치(pitch)성분에 큰 가중치(weighting)를 줌으로써 화자간 변이(inter-speaker variation)가 커지도록 하는 가중치 함수를 제안한다. 실험 결과, LPCC만을 특징 파라미터로 사용하였을 경우보다 잔여 켑스트럼 (RCEP)과 LPCC를 동시에 사용했을 경우 약 6%가량의 인식 오류율이 향상 되었으며, 제안한 가중치 함수를 적용한 잔여 켑스트럼 (RCEP)과 LPCC를 동시에 사용했을 경우 인식 오류율이 가중치를 주지 않은 경우보다 약 2.45%가량 개선되었다.

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