• Title/Summary/Keyword: method of phases

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Kinetic Characterization of Swelling of Liquid Crystalline Phases of Glyceryl Monooleate

  • Lee, Jae-Hwi;Choi, Sung-Up;Yoon, Mi-Kyeong;Choi, Young-Wook
    • Archives of Pharmacal Research
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    • v.26 no.10
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    • pp.880-885
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    • 2003
  • Research in this paper focuses on the kinetic evaluation of swelling of the liquid crystalline phases of glyceryl monooleate (GMO). Swelling of the lamellar and cubic liquid crystalline phases of GMO was studied using two in vitro methods, a total immersion method and a Franz cell method. The swelling of the lamellar phase and GMO having 0 %w/w initial water content was temperature dependent. The swelling ratio was greater at $20^{\circ}^C than 37^{\circ}^C$ . The water uptake increased dramatically with decreasing initial water content of the liquid crystalline phases. The swelling rates obtained using the Franz cell method with a moist nylon membrane to mimic buccal drug delivery situation were slower than the total immersion method. The swelling was studied by employing first-order and second-order swelling kinetics. The swelling of the liquid crystalline phases of GMO could be described by second-order swelling kinetics. The initial stage of the swelling (t < 4 h) followed the square root of time relationship, indicating that this model is also suitable for describing the water uptake by the liquid crystalline matrices. These results obtained from the current study demonstrate that the swelling strongly depends on temperature, the initial water content of the liquid crystalline phases and the methodology employed for measuring the swelling of GMO.

A Study on Single Position Driving Meethod of Switched Reluctance Motor (Switched Reluctance Motor의 Single Position Sensor 구동에 관한연구)

  • 정윤철
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.709-712
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    • 2000
  • In general three position sensors are needed to drive three phases SRM. Single position sensor driving method for three phases Switched Reluctance Motor(SRM) is proposed in this paper. By using single position sensor the cost of SRM is reduced. But position sensor the cost of SRM is reduced. But position detection at the staring is needed for single position sensor driving method. In this paper we propose the active align method to detect the relative position of rotor to three phases and align to the nearest phase. We proved the validity of the method by experiment and compare with other method.

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Alternative Method of AWG Phase Measurement Based on Fitting Interference Intensity

  • Oh, Yong Ho;Lim, Sungwoo;Go, Chun Soo
    • Journal of the Optical Society of Korea
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    • v.16 no.2
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    • pp.91-94
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    • 2012
  • Arrayed waveguide grating (AWG) phase errors are normally assessed from the Fourier transform of the interference intensity data in the frequency domain method. However it is possible to identify the phases directly from the intensity data if one adopts a trial-and-error method. Since the functional form of the intensity profile is known, the intensities can be calculated theoretically by assuming arbitrary phase errors. Then we decide the phases that give the best fit to the experimental data. We verified this method by a simulation. We calculated the intensities for an artificial AWG which is given arbitrary phases and amplitudes. Then we extracted the phases and amplitudes from the intensity data by using our trial-and-error method. The extracted values are in good agreement with the originally given values. This approach yields better results than the analysis using Fourier transforms.

The Effect of The Lunar and Planetary Phases Drawing Module on Students' Conceptual Change and Achievement

  • Kim, Sang-Dal;Kim, Jong-Hee
    • Journal of the Korean earth science society
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    • v.25 no.3
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    • pp.176-184
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    • 2004
  • The concept of 'the lunar and planetary phases' is very difficult to understand and students may have various misconceptions on this concept. A module drawing the lunar and planetary phases was developed with the application of the simplifying conditions method. The effects of instruction using the module drawing the lunar and planetary phases on the conceptual change and the achievement was investigated in the consideration of learners' characteristics (spatial perception ability, science inquiry ability, required pre-requested learning ability). Findings were as follows: 1) This module was effective for learners' conceptual change and achievement, 2) This module had a positive influence for development the learners' characteristics and conceptual change with the middle level of science inquiry ability, the middle and low level of required pre-requisite learning ability, and middle level of the spatial perception ability.

Preparation of Ultrafine Au-Pb Particles by Gas-evaporation Technique

  • Ohno, Takehisa;Funaguchi, Hironori
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.158-159
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    • 2006
  • Ultrafine Au-Pb particles prepared by two method, (1) simultaneous evaporation of Au and Pb in inert gas and (2) subsequent vapor condensation of Pb in a differentially evacuated tube onto flying Au nanoparticles prepared by gasevaporation technique, were observed by electron microscopy. In the method (1), the particles that grew at the region where the two smoke masses converged, consisted of alloy phases. In the method (2), the particles consisted of two or three phases of Au, $Au_2Pb$, $AuPb_2$ and Pb phases in turn from the inner part, Pb-rich particles being composed of only two phases of $AuPb_2$ and Pb.

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A Study on Lee Jae Won's Application of the Sa-am Acupuncture Method (소곡(小谷) 이재원(李在元)의 사암침법(舍岩鍼法) 운용(運用)에 관(關)한 연구(硏究))

  • Jung, Yoo-Ong;Cha, Woongseok;Kim, Namil
    • The Journal of Korean Medical History
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    • v.23 no.2
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    • pp.89-101
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    • 2010
  • Lee Jae Won is a scholar who wrote the most in Euirim, a representative Oriental Medical magazine after the liberation of Korea, on the Sa-am Acupuncture Method. In order to understand the principles of this method, he proposed rather distinctive theories called the Comparative Pulse Diagnosis and the Five Constitutions. Lee Jae Won distinguished the deficiency and exuberance of the Five Phases through the Comparative Pulse Diagnosis, and set harmonizing the Five Phases by tonifying the deficient and purging the exuberant as the object of the Sa-am Acupuncture Method. He took pulses from both the patient's hands and distinguished the deficiency and exuberance of the five viscera. Then, he balanced the Five Phases by tonifying the weakest viscus and purging the strongest viscus. Lee Jae Won argued that because the Five Constitutions are something that one has innately, people suffer from differnet diseases according to their constitutions. Therefore, he argued, when treating a patient, one should first decide the constitution of the patient and then treat the patient according to his/her deficiency or exuberance. From the late 50's to early 60's, Lee Jae Won wrote Acupuncture and Moxibustion According to Yin-Yang and the Five Phases, explaining the principles of the Sa-am Acupuncture Method and its applications. Seen from this, Lee Jae Won is a person from whom we can confirm the historical lineage of the Sa-am Acupuncture Method after the liberation of Korea.

The Selection of Optimum Measurement Method of Antimicrobial Activity and Constituent Phase of Yuggi Alloy according to Heat Treatment Condition (유기합금의 열처리조건에 따른 구성상의 제어와 최적 항균특성 측정방법의 선정)

  • Park, Kyu-Ha;Hwang, Dae Youn;Son, Hong-Joo;Choi, Ji Woong;Kim, Hye Sung
    • Journal of the Korean Society for Heat Treatment
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    • v.34 no.5
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    • pp.233-238
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    • 2021
  • The mechanical, anti-tarnishing, and corrosion characteristics of Yuggi (Cu-22wt%Sn) alloy are greatly affected by fraction of constituent phases according to heat treatment method. The Yuggi heat-treated at 750℃ has a β1' phase of 98% or more, which is a high-temperature disordered beta phase, on the other hand, cast Yuggi that Sn is solid-solutioned into Cu consists with α-phase over 60v/o. This difference of constituent phases of Yuggi may cause a difference in dissolution of Cu under antimicrobial test condition. Nonetheless, few studies have been conducted on the effect of fraction of constituent phases and constituent phases in antimicrobial activity. In addition, few studies have also been conducted on the suitable method measuring the antimicrobial activity of Yuggi. Hence, the purpose of this study is to provide an optimum measurement method of antimicrobial activity, and to evaluate quantitatively the effect of constituent phases on antimicrobial activity.

Risk Analysis of Suspension Bridge by a Linear Adaptive Weighted Response Surface Method (선형 적응적 가중 응답면기법에 의한 현수교의 위험도 분석)

  • Cho, Tae Jun;Kim, Lee Hyeon;Cho, Hyo Nam
    • Journal of Korean Society of Steel Construction
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    • v.20 no.1
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    • pp.93-104
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    • 2008
  • study deals with the reliability assesment for the 5-year phases of a suspension bridge construction in Korea. The main objectives of this study are; (1) the evaluation of the reliability of a suspension bridge by considering an ultimate limit state for the fracture of main cable wires, (2) the determination of the critical phases among 28 construction stages for the deck erection, and (3) the evaluation of the reliability of the limit state for the erection control during construction stages. The research and the design of the suspension bridge have been focused on the state of construction mainly based on empirical data. Based on the recent survey of the distribution of accidents in Korean railways, over 80% of the accidents related to the uncertainties in human error, planning, design, materials and loads during construction have ben reported before the completion of construction. While many researches have evaluated the safety of bridges, the uncertainties in the construction phases have not been well treated in a guidelines or a specifications. An improved adaptive response surface method is used for the risk assessment in the construction phases of the target suspension bridge.

Sampling Methods for Quantification of Solid-state Phases in Powder Samples with Solid-state NMR Spectroscopy

  • Han, Oc-Hee;Kim, Sun-Ha;Ko, Tae-Jung
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1077-1079
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    • 2009
  • To minimize the variance in the quantification of solid-state phases in powder samples, gently placing polycrystalline samples one next to another directly in a sample holder is better than trying to mix them homogeneously prior to transferring to a sample holder. However, the solid-state cross polarization-magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy results demonstrated that it is essential in this sampling method to place all the samples in the location of consistent signal sensitivity. The same sampling method may be employed in other spectroscopic quantification techniques of solid-state phases if the method to limit the sample to the location with uniform signal sensitivity in the sample holder is adapted to each technique.

2-phase Excitation Method for Reducing Vibration and Noise of an SRM (SRM의 진동소음 저감을 위한 2권선 여자방식)

  • Choi, Gi-Young;Ahn, Jin-Woo;Hwang, Young-Moon
    • Proceedings of the KIEE Conference
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    • 1999.11b
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    • pp.76-78
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    • 1999
  • In this paper, the 2-phase excitation method is proposed to reduce vibration and noise. This excitation method produces reluctance torque by mutual action between two phases as well as conventional-reluctance torque due to two phases excitation at a time. The vibration and acoustic noise is reduced thought the sequential phase excitation. This is because that the scheme reduces abrupt change of excitation level by distributed. balanced excitation.

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