• 제목/요약/키워드: nut

검색결과 539건 처리시간 0.032초

오미자 씨 오일의 화장품 소재로서 유효성 평가 (The Evaluation on the Effectiveness as a Cosmetic Material of Oil Extracted from Schizandra Chinensis Seed)

  • 양재찬
    • 한국응용과학기술학회지
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    • 제29권2호
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    • pp.231-237
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    • 2012
  • 오미자 씨 오일의 화장품 소재로서 가능성을 평가하기 위해 GC와 GC/MSD를 사용하여 안정성 평가 및 성분 분석을 실시하였다. 그 결과 주요성분은 팔미틱산과 올레익산으로 나타났다. 오미자 씨 오일은 열에 의한 성분변화가 없고, 소재 자체의 안정성이 뛰어난 것으로 나타났다. 또한, DPPH(1,1-Diphenyl-2-picrylhydrazyl) 라디칼 소거능 실험을 통하여 항산화 효능을 측정한 결과 오미자 씨 오일이 마카다미아 오일과 올리브 오일에 비하여 높은 항산화 효능을 나타내었다. 콜라겐 합성능 또한 뛰어난 것으로 평가되었다. 따라서, 오미자 씨 오일은 화장품 소재용으로 유용하게 활용될 수 있는 가능성을 가진 것으로 평가되었다.

Robust Fuzzy Logic Current and Speed Controllers for Field-Oriented Induction Motor Drive

  • El-Sousy, Fayez F.M.;Nashed, Maged N.F.
    • Journal of Power Electronics
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    • 제3권2호
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    • pp.115-123
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    • 2003
  • This paper presents analysis, design and simulation for the indirect field orientation control (IFOC) of induction machine drive system. The dynamic performance of the IFOC under nominal and detuned parameters of the induction machine is established. A conventional proportional plus integral-derivative (PI-D) two-degree-of-freedom controller (2DOFC) is designed and analysed for an ideal IFOC induction machine drive at nominal parameters with the desired dynamic response. Varying the induction machine parameters causes a degredation in the dynamic response for disturbance rejection and tracking performance with PI-D 2DOF speed controller. Therefore, conventional controllers can nut meet a wide range of speed tracking performance under parameter variations. To achieve high- dynamic performance, a proposed robust fuzzy logic controllers (RFLC) for d-axis rotor flux, d-q axis stator currents and rotor speed have been designed and analysed. These controllers provide robust tracking and disturbance rejection performance when detuning occurres and improve the dynamic behavior. The proposed REL controllers provide a fast and accurate dynamic response in tracking and disturbance rejection characteristics under parameter variations. Computer simulation results demonstrate the effectiveness of the proposed REL controllers and a robust performance is obtained fur IFOC induction machine drive system.

적응 퍼지제어기를 이용한 유도전동기 회전자의 시정수 추정 및 보상 (Time Constant Estimation and Compensation of Induction Motor rotor using Adaptive Fuzzy Controller)

  • 이영실;이정철;이흥균;남수명;김종관;정동화
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2004년도 전력전자학술대회 논문집(1)
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    • pp.42-45
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    • 2004
  • This paper is proposed an adaptive fuzzy controller of induction motor drive. The adaptive fuzzy controller approach for an estimate of the rotor time constant which is used to adjust the estimate of the slip angular speed. An estimate of the rotor time constant was obtained using an model reference adaptive system(MRAS) in a fuzzy control scheme. The rotor time constant was estimated by utilizing the rotor nut estimates. This paper is proposed the theoretical analysis as well as the simulation results to verify the effectiveness of the new method.

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하이드로 임베딩시 체결용 연결요소의 형상 최적화 연구 (Studies on the Shape Optimization of Connecting Element for Hydro-Embedding)

  • 김봉준;김동규;김동진;문영훈
    • 소성∙가공
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    • 제14권9호통권81호
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    • pp.756-763
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    • 2005
  • The applicability and productivity of hydroforming process can be increased by combining pre- and post-forming processes such as the bending, piercing and embedding process. For the fabrication of automotive parts, the hollow bodies with connecting nuts are widely used to connect parts together. Hollow body with connecting nuts has been conventionally fabricated by welding nuts or screwing in autobody screws. It requires multiple steps and devices fur the welding and/or screwing Therefore in this study, hydro-embedding process that combines the hydraulic embedding of connecting element(nut) with hydroforming process is investigated. Studies on the hydro-embedding technology have been performed to optimize the shape of the connecting element by analyzing the deformed mode of the embedded tube The effects of the shape of the screw tip, screw thread and shape of thread on the connection force between the tube and the connecting element have been investigated to optimize the shape of connecting element. Finite element analysis has also been performed to provide deformation behaviors of the tube surrounding a hole produced by hydro-embedding.

A New Analog Switch CMOS Charge Pump Circuit without Body Effect

  • Parnklang, Jirawath;Manusphrom, Ampual;Laowanichpong, Nut;Tongnoi, Narongchai
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.212-214
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    • 2005
  • The charge-pump circuit which is used to generate higher voltage than the available supply voltage has wide applications such as the flash memory of EEPROM Because the demand for high voltage comes from physical mechanism such as the oxide tunneling, the required pumped voltage cannot be scaled as the power supply voltage is scaled. Therefore, an efficient charge-pump circuit that can achieve high voltage from the available low supply voltage is essential. A new Analog Switch p-well CMOS charge pump circuit without the MOS device body effect is processed. By improve the structure of the circuit's transistors to reduce the threshold voltage shift of the devices, the threshold voltage of the device is kept constant. So, the circuit electrical characteristics are higher output voltage within a shorter time than the conventional charge pump. The propose analog switch CMOS charge pump shows compatible performance of the ideal diode or Dickson charge pump.

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한국의 전통적 기능성 식품의 이용에 대한 역사적 고찰 (The Historical Study of Korean Traditional Funtional Food)

  • 한복진
    • 동아시아식생활학회지
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    • 제6권2호
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    • pp.235-255
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    • 1996
  • Natural substances, exploited in our daily life, have been applied to drugs to treat diseases and developed to functional foods by appropriate preparations, and these foods give beneficial effects on physical activities. In this paper, the utilization of traditional functional foods was studied with refer ring to old ancient writings published in the front-end of Chosun dynasty. The utilized vegetables were march mallow, turnip, radish, Chinese cabbage, lettuce, spinach, cucumber winter buds, flesh of a cabbage, eggplant, taro, burdock, Parsley, watershield plant, crown daisy, bamboo shoots, garlic, scallion, onion, acorn, bark of a tree, white goosefoot leaf, leaf of bean, pine mushroom, bracken. yam, mugwort, tea, ginseng, peppermint, fruit of the Maximowiczia chinensis, smartweed and pepper. The utilized fruits were chestnut, Chinese date, pine nuts, walnut, gingko nut, citrus. crab apple, pear, peach, grape, pomegranate, plum, Chinese quince, fig and watermelon. The utilized cereal were rice, barley, bean, buckweat and Job's-tears. The utilized sweetenings and seasonings were honey, wheat-gluten, sugar, oil, salt, soy sauce and vinegar. Our ancestors had a balanced diet using the various foods, and especially had a fundamental concept of "Foods have the efficacy of a remedy".edy".uot;.

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Constituents Released from Streptococcus mutans Attenuate Arecoline-mediated Cytotoxicity in HGF Cells by Altering Intracellular $Ca^{2+}$ Signaling

  • Erkhembaatar, Munkhsoyol;Oh, Hyuncheol;Kim, Min Seuk
    • International Journal of Oral Biology
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    • 제39권1호
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    • pp.41-47
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    • 2014
  • Streptococcus mutans (S. mutans) is a facultative anaerobic bacterium mainly found in the oral cavity and is known to contribute to tooth decay and gingivitis. Recent studies on intestinal microbiota have revealed that microorganisms forming a biofilm play important roles in maintaining tissue homeostasis through their own metabolism. However, the physiological roles of oral microorganisms such as S. mutans are still unclear. In our current study, we identified that constituents released from S. mutans (CR) reduce arecoline-mediated cytotoxicity without producing toxic effects themselves. Arecoline, as a major alkaloid of areca nut, is known to mediate cytotoxicity on oral epithelial cells and induces a sustained intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) increase that is cytotoxic. The exposure of human gingival fibroblast (HGF) cells to CR not only inhibited the sustained $[Ca^{2+}]_i$ increase but also the initial $[Ca^{2+}]_i$ elevation. In contrast, CR had no effects on the gene regulation mediated by arecoline. These results demonstrate that S. mutans has physiological role in reducing cytotoxicity in HGF cells and may be considered a novel pharmaceutical candidate.

영상처리 방법을 이용한 T-Bar의 볼트와 너트 유무 판별 (Discrimination of Bolt and Nut's Presence in a T-Bar Using Image Processing Method)

  • 주기세;김은석
    • 한국정보통신학회논문지
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    • 제13권5호
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    • pp.937-943
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    • 2009
  • 본 논문에서는 영상 처리를 이용하여 차체의 진동에 영향을 미치는 자동차 T-Bar부품에서의 볼트와 너트의 존재 유무를 판별하는 알고리즘이 소개된다. T-Bar의 볼트와 너트 존재 유무를 판별하기 위하여 볼트와 너트의 특징치들이 학습되고 통계적 패턴매칭 방법을 이용하여 학습된 특징치들이 매칭된다. 또한 영상마다 볼트와 너트들의 화소값이 크게 변화하여 매칭율이 낮아지기 때문에 화소값의 최대와 최소 변화률이 이용된다. 본 논문에서 제안한 방법은 기존의 방법들에 비해 검사시간을 대폭 축소시켜 실시간이 요구되는 검사 자동화 분야에 아주 효율적이다.

박용엔진 실린더 커버 스터드의 구조거동 분석 (Structural Behavior of the Cylinder Cover Stud of Marine Diesel Engine)

  • 김병주;이재옥;박진수;김세락
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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    • pp.267-268
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    • 2006
  • The cylinder cover stud of low-speed marine diesel engine is more than just a stud. It is a large structural element occasionally weighing over 200 kg used for assembling the combustion chamber components. Therefore, to understand the structural behavior of the stud and design it safely is quite important considering a catastrophic failure which can be arisen from an inadequate use of it. In this paper, the analysis results of the structural behavior of the stud is introduced. Strain measurement results compared with FE analysis results are summarized. The results showed that 1) the stud stress increased with engine operating load, 2) the maximum stress amplitude was about 10 MPa which is far smaller than the stud's fatigue strength of 61 MPa, 3) the stress ratio is higher than 0.9 and the stud's load factor is about 20 %, and 4) about 7 % of initial pressure tightening load was reduced while changing to a nut tightened condition.

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저항운동치료 처방에 관한 연구 (A Study of Resistive Therapeutic Exercise Prescription)

  • 배성수;김태숙;김은주
    • The Journal of Korean Physical Therapy
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    • 제11권1호
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    • pp.149-156
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    • 1999
  • Resistive therapeutic exercise prescription goal is to improve functional performance and capabilities through the development of increased muscular strengh endurance or power. Resistance can be applied to either dynamic or static muscle contractions. Resistive therapeutic exorcise can be carried nut concentrically, eccentrically, isometrically, isokinetically. Neurodevelopmental treatment has not resistive therapeutic exercise concept. But proprioceptive neuromuscular facilitate techniques have resistive therapeutic exercise concept with pattens and techniques. It is aid muscle contraction, motor control and increase strength. Manual muscle testing will help the therapist establish a qualitative and quantitative baseline level of strength. Manual resistance maybe applied a against controlled lengthening contraction re static contraction of a muscle. A repetition maximum is not easy to calculate and is not the most accurate method available today to measure strength before of after a resistive therapeutic exercise program. Oddvar Holten Diagram is essy to calculate and is the most accurate method available today to measure strength before of after a resistive therapeutic exercise program. Plyometric training emphasize the development of muscular power and coordination. Quick bursts of force in functional movement patterns are often necessary of a patient is to return to high-demand occupational, recreational or sports related activities.

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