• 제목/요약/키워드: Range-free

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이송되는 컵 내부의 자유 표면의 거동 특성에 대한 수치해석 (A Numerical Analysis of the Behavior of the Free Surface in a Moving Cup)

  • 홍태협;채희문;김창녕
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회B
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    • pp.2997-3002
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    • 2007
  • A manipulator is operated for the motion of mechanical hands or arms by mechanical mechanism. When a cup including liquid inside is shifted by a manipulator, it is important to know how a free surface of the liquid moves. In this study, non-dimensional parameters have been found that affect the rise of the free surface in a cup moving with constant acceleration. The non-dimensional parameters are the dimensionless time, the ratio of inertia effect to vicous effect (Reynolds number), aspect ratio of the liquid inside the cup and acceleration ratio (Froude number). Through this study, the height of the free surface rise in a cup has been predicted. Generally the maximum rise of the free surface is dependent on the Reynolds number and Froude number strongly, but on the aspect ratio weakly. But the influence of the aspect ratio on the maximum rise of the free surface in not negligible in the range 10 < Re < 100.

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비파의 유리당, 유기산 및 유리아미노산의 조성 (Composition of Free Sugars Organic Acids and Free Amino Acids in Loquat Flesh)

  • 조영숙;박석규;이홍열
    • 한국식품영양과학회지
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    • 제20권1호
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    • pp.89-93
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    • 1991
  • For the investigation of major taste components in loquat(Eiobotrya japonica) flesh its conte-nts and compositions of free sugars organic aicds and free amino acids were analyzed Major free sugars of the fully ripened loquat were fructose glucose and sucrose and their contents were 3,71, 3.42 and 0.46%(w/w) respectively. The content of total sugar 13.7% was 2 times higher than that of the unripe fruit. The content of total organic acid was about 0.2% (w/w) and major organic acids were malic acid -89mg% formic acid -32mg% and oxalic acid -26%mg% Thirteen kinds of free amino acids from the fully ripened loquat were confirmed. Major free amino acids were aspartic acid valine glutamic acid serine alanine and histidine and their contents were in the range of 18-30mg%.

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자유유동 난류강도가 터빈 캐스케이드내 3차원 난류유동 특성에 미치는 영향에 관한 전산해석 (Numerical Analysis on Effects of Free-Stream Turbulence Intensity on the Three-dimensional Turbulent Flow Characteristics in a Turbine Cascade)

  • 윤덕규;이우상;김대현;정진택
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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    • pp.371-374
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    • 2006
  • The objective of this study is to determine the influence of free-stream turbulent intensity on the three-dimensional turbulent flow in a linear turbine cascade. The range of free-stream turbulence intensity considered is 0.7~10%. This study was performed numerically. The results show that the mass averaged loss coefficient increased according to the increase of free-stream turbulence intensity due to increased value of the mass averaged total pressure loss coefficient which was higher than the decreased value of the mass averaged secondary flow loss coefficient. The loss coefficient distribution was changed suddenly at a free-stream turbulence intensity of 10% while the loss coefficient distribution was rarely changed at a lower free-stream turbulence intensity of 5%.

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국소 거리정보를 얻을 수 있는 다중 이동로보트 환경에서의 Hopfield 신경회로 모델을 이용한 충돌회피 경로계획 (A collision-free path planning for multiple mobile robots by using hopfield neural net with local range information)

  • 권호열;변증남
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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    • pp.726-730
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    • 1990
  • In this paper, assuming that local range information is available, a collision-free path planning algorithm for multiple mobile robots is presented by using Hopfield neural optimization network. The energy function of the network is built using the present position and the goal position of each robot as well as its local range information. The proposed algorithm has several advantages such as the effective passing around obstacles with the directional safety distance, the easy implementation of robot motion planning including its rotation, the real-time path planning capability from the totally localized computations of path for each robot, and the adaptivity on arbitrary environment since any special shape of obstacles is not assumed.

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고속 ADC 회로를 위한 100 MS/s의 샘플링의 SHA 설계 (Development of a SHA with 100 MS/s for High-Speed ADC Circuits)

  • 채용웅
    • 한국전자통신학회논문지
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    • 제7권2호
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    • pp.295-301
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    • 2012
  • 본 논문에서는 고속 ADC의 앞단에서 사용하기 위한 1 $V_{pp}$의 입력 신호 범위에서 12 Bit의 해상도를 갖고 100 MS/s의 샘플링 속도에서 동작하는 SHA를 설계하였다. 제안된 시스템은 입력 주파수가 5 MHz, 샘플링 주파수 100 MHz 일 때 SFDR(Spurious Free Dynamic Range)가 약 66.3 dB로 해상도가 떨어졌으나 feedthrough를 제거한 회로는 SFDR이 약 73 dB로 12 bit 해상도를 갖는다.

방사 사육과 배터리 사육 산란계에서 난질 : 난가와 산란계 주령에 따른 난질의 비교 (Egg Quality in Battery Cage and Free-Range Systems : with Reference to Comparison of Eggs Based on Price and Hens' Age)

  • 김대우;강석민;양영록;김지민;윤형숙;전중환;최양호
    • 한국유기농업학회지
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    • 제24권1호
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    • pp.115-122
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    • 2016
  • The main purpose of the current study was to compare quality of eggs 1) produced from hens housed in battery cages vs. free range, 2) from young vs. old hens, and 3) tagged with the lowest vs. the highest price in a local franchised mart. The ages of hens, at which their eggs were used for the analysis of quality, were 70 weeks old in the experiment 1, 22 and 47 weeks old in the experiment 2, and were unknown in the experiment 3. Eggs were analyzed for weight, albumen height, Haugh unit, shell color, shell strength, shell thickness, shell weight, yolk color, yolk weight, and egg white weight. In the experiment 1, significant differences were detected between two housing systems in shell color, shell weight, yolk color, and yolk weight (P<0.05), but not in egg weight, albumen height, Haugh unit, shell strength, shell thickness, and egg white weight (P>0.05). Although egg weight was slightly but not significantly higher in battery cages by 2.2 g than in free range, yolk weight was significantly higher in battery cage (P<0.05). On the contrary, shell color was greatly increased in free range system by 68.5% compared with battery cage. In the experiment 2, there were significant differences between young and old hens in egg weight, albumen height, Haugh unit, shell strength, shell weight, yolk color and yolk weight (P<0.05). Egg weight, shell weight, yolk color and yolk weight were increased in old hens than young hens while albumen height, Haugh unit, and shell strength were decreased. In the experiment 3, egg weight, albumen height, Haugh unit, shell weight, and egg white weight were significantly higher in the highest priced eggs than the lowest ones (P<0.05), whereas shell strength and yolk color were lower (P<0.05) but shell color, shell thickness and yolk weight were not different (P>0.05). So, egg freshness was clearly higher in the highest priced ones than in the lowest (P<0.05). Due to the limited information on raising and husbandry of laying hens whose eggs were tested for egg quality in the current study, the present results should be cautiously interpreted while contributing to the future study as a basis in this field.

REBCO 초전도 박막제조를 위한 Fluorine-free MOD 전구체 용액 개발 (Development of Fluorine-free MOD Precursor Solution for fabricating REBCO Superconducting Films)

  • 김병주;임선원;김호진;홍계원;이희균
    • Progress in Superconductivity
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    • 제7권2호
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    • pp.152-157
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    • 2006
  • New precursor solution with dichloroacetic acid (DCA) was developed for fabricating high $J_c$ REBCO film. DCA based-precursor solution was coated on $LaAlO_3$(001) substrate by dip coating method. Processing parameters such as oxygen partial pressure, water vapor, ramping rate and pyrolysis temperature were controlled in order to obtain a good epitaxial film. The film with thickness of 0.5 micrometer was obtained by single coating and no crack was observed at calcined films. Oxygen partial pressure was controlled in the range of $100{\sim}1,000$ ppm and conversion heat treatment was carried out at the temperature range of $705-765^{\circ}C$. A critical transition temperature ($T_c$) of 90 K and a critical transport current density ($J_c$) of $>0.5\;MA/cm^2$ (77 K and self-field) were obtained for the GdBCO film. It is thought that fluorine-free MOD solution using DCA is promising precursor solution for fabricating high quality REBCO films.

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Quantitative Label-free Biodetection of Acute Disease Related Proteins Based on Nanomechanical Dynamic Microcantilevers

  • Hwang, Kyo-Seon;Cha, Byung-Hak;Kim, Sang-Kyung;Park, Jung-Ho;Kim, Tae-Song
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제7권3호
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    • pp.151-160
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    • 2007
  • We report the label-free biomolecules detection based on nanomechanical micro cantilevers operated in dynamic mode for detection of two marker proteins (myoglobin and creatin kinase-MB (CK-MB)) of acute myocardical infarctions. When the specific binding between the antigen and its antibody occurred on the fuctionalized microcantilever surface, mechanical response (i.e. resonant frequency) of microcantilevers was changed in lower frequency range. We performed the label-free biomolecules detection of myoglobin and CK-MB antigen in the low concentration (clinical threshold concentration range) as much as 1 ng/ml from measuring the dynamic response change of micro cantilevers caused by the intermolecular force. Moreover, we estimate the surface stress on the dynamic microcantilevers generated by specific antibody-antigen binding. It is suggested that our dynamic microcantilevers may enable one to use the sensitive label-free biomolecules detection for application to the disease diagnosis system based on mechanical immuno-sensor.

Effects of the Xe content on the electro-optical properties in the mercury-free Flat Fluorescent Lamp

  • Chung, Kyu-Yong;Lee, Sang-Mok;Jeong, Yoon-Chul;Sohn, Sang-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1577-1579
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    • 2007
  • Xe content is one of important factors related to characteristics of the mercury-free flat fluorescent lamp. The electro-optical properties of lamp were investigated for wide range of Xe content in Xe-Ne mixing gas. The maximum luminance of $9,289\;cd/m^2$ and efficacy of 3 lm/W was obtained with Xe 90 %.

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대향타겟식스퍼터링으로 제작된 ZnO 박막의 C-축 배향성 (C-axis Orientation of ZnO Thin Films Prepared by FTS Method)

  • 금민종;손인환;최형욱;최동진;김경환
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.685-687
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    • 1999
  • We prepared ZnO thin film with Facing Targets Sputtering system that can deposit thin film in plasma-free situation and change the deposition condition in wide range. And prepared thin films c-axis orientation and grain size were analyzed by XRD(x-ray dffractometer). In the results, we suggest that FTS system is very suitable to preparing high quality ZnO thin film with good c-axis orientation.

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