• Title/Summary/Keyword: Five phase

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Development of the Interfacial Area Concentration Measurement Method Using a Five Sensor Conductivity Probe

  • Euh, Dong-Jin;Yun, Byong-Jo;Song, Chul-Hwa;Kwon, Tae-Soon;Chung, Moon-Ki;Lee, Un-Chul
    • Nuclear Engineering and Technology
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    • v.32 no.5
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    • pp.433-445
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    • 2000
  • The interfacial area concentration (IAC) is one of the most important parameters in the two-fluid model for two-phase flow analysis. The IAC can be measured by a local conductivity probe method that uses the difference of conductivity between water and air/steam. The number of sensors in the conductivity probe may be differently chosen by considering the flow regime of two-phase flow. The four sensor conductivity probe method predicts the IAC without any assumptions of the bubble shape. The local IAC can be obtained by measuring the three dimensional velocity vector elements at the measuring point, and the directional cosines of the sensors. The five sensor conductivity probe method proposed in this study is based on the four sensor probe method. With the five sensor probe, the local IAC for a given referred measuring area of the probe can be predicted more exactly than the four sensor probe. In this paper, the mathematical approach of the five sensor probe method for measuring the IAC is described, and a numerical simulation is carried out for ideal cap bubbles of which the sizes and locations are determined by a random number generator.

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Did the current correspondence scheme between Five Viscera and Five Phases arise from social and humane hegemony conflict? -some clues from "Changgongyeoljeon(倉公列傳)" in "Sagi(史記)" (현행 오장-오행 배속은 사상 논쟁의 산물인가 -"사기.창공열전"을 중심으로-)

  • Jang, Mi-Jung;Kim, Ki-Wang
    • Journal of Korean Medical classics
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    • v.23 no.3
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    • pp.127-138
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    • 2010
  • Traditional Chinese Medicine is based on Five Phase theory that link Liver, Heart, Spleen, Lung, Kidney to Wood, Fire, Earth, Metal, Water respectively. Recently, some argue that this correspondence scheme had been established by political or socio-humane issues in early Eastern Han dynasty. But according to our analysis on Changgongyeoljeon(in Sagi), it has been revealed that this scheme had their own history from early Western Han dynasty. So we may conclude that people with medical profession had preserved the current correspondence scheme in Five Phase theory regardless trends of literature and politics in Western and Eastern Han dynasty.

An Improved Contention Access Mechanism for FPRP to Increase Throughput

  • Yang, Qi;Zhuang, Yuxiang;Shi, Jianghong
    • ETRI Journal
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    • v.35 no.1
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    • pp.58-68
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    • 2013
  • Five-phase reservation protocol (FPRP) is a contention-based media access control protocol for wireless ad hoc networks. FPRP uses a five-phase reservation process to establish slot assignments based on time division multiple access. It allows a node to reserve only one slot in an information frame. Once a node has reserved a slot, it will cease contending for other slots. As a result, there may be less contending nodes in the remaining slots, so the time slots in an information frame are not fully used by FPRP. To improve time slot utilization, this paper proposes an improved pseudo-Bayesian algorithm, based on which an improved contention access mechanism for FPRP is proposed, in which nodes are allowed to contend for more than one slot in a reservation frame according to a certain probability/priority. Simulation results indicate that the proposed mechanism performs better than FPRP in time slot utilization and hence the network throughput under various scenarios.

Common-Mode Voltage and Current Harmonic Reduction for Five-Phase VSIs with Model Predictive Current Control

  • Vu, Huu-Cong;Lee, Hong-Hee
    • Journal of Power Electronics
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    • v.19 no.6
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    • pp.1477-1485
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    • 2019
  • This paper proposes an effective model predictive current control (MPCC) that involves using 10 virtual voltage vectors to reduce the current harmonics and common-mode voltage (CMV) for a two-level five-phase voltage source inverter (VSI). In the proposed scheme, 10 virtual voltage vectors are included to reduce the CMV and low-order current harmonics. These virtual voltage vectors are employed as the input control set for the MPCC. Among the 10 virtual voltage vectors, two are applied throughout the whole sampling period to reduce current ripples. The two selected virtual voltage vectors are based on location information of the reference voltage vector, and their duration times are calculated using a simple algorithm. This significantly reduces the computational burden. Simulation and experimental results are provided to verify the effectiveness of the proposed scheme.

Virtual Signal Injected MTPA Control for DTC Five-Phase IPMSM Drives

  • Liu, Guohai;Yang, Yuqi;Chen, Qian
    • Journal of Power Electronics
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    • v.19 no.4
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    • pp.956-967
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    • 2019
  • This paper introduces a virtual signal injected maximum torque per ampere (MTPA) control strategy for direct-torque-controlled five-phase interior permanent magnet synchronous motor (IPMSM) drives. The key of the proposed method is that a high frequency signal is injected virtually into the stator flux linkage. Then the responding stator current is calculated and regulated to compensate the amplitude of the flux linkage. This is done according to the relationship between the stator current and the stator flux linkage. Since the proposed method does not inject any real signals into the motor, it does not cause any of the problems associated with high-frequency signals, such as additional copper loss and extra torque ripple. Simulation and experimental results are offered to verify the effectiveness of the proposed method.

Calibration of frequency propagation channel sounder based on five-port reflectometer

  • Yem Van;Braga Judson;Huyart B;Begaud X;de Sousa F.R;Huyen Nguyen Bich
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.23-26
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    • 2004
  • Five-port reflectometer which consists of a ring with 5 arms (two inputs, three outputs) and three RF power detectors has been used as a vector network analyser, a demodulator in the homodyne receiver as well as in Phase Looked Loop (PLL) and so on. Calibration of five-port reflectometer is an important task. In this paper, we present a calibration method of five-port for a propagation channel sounder. The method is based on measurement of the phase differences between the three voltages at the five-port's outputs in order to determine the ratio of two input incident waves. The frequency channel sounder based on five-port is calibrated for each frequency from 2.2 GHz to 2.6 GHz with 1 MHz step. This method can also determine the absolute delays of each propagation path in the propagation channel. The calibration method is validated using measurement data.

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Analysis of Insulation Aging in Operating High Voltage Motors (운전중인 고압전동기에서 절연열화 분석)

  • Kim, Hee-Dong;Ju, Young-Ho
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2175-2178
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    • 2005
  • During normal machine operation, partial discharge(PD) measurements were performed with turbine generator analyzer(TGA) in five high voltage motors(rated 6.6kV). These high voltage motors were installed with 80pF capacitive couplers at the terminal box. The PD patterns were displayed two dimensional and three dimensional. TGA summarizes each plot with two quantities such as the normalized quantity number(NQN) and the peak PD magnitude(Qm). Off-line PD measurements were conducted on five motors. These motors were energized to 3.81kV. The PD levels in pC were measured with a conventional digital PD detector. The comparison of positive to negative PD indicates whether the defect elements of PD are within the insulation or on the insulation surface. Internal discharges were generated in phase A, B and C of COP-B and pulv.-B, in phase B of Pulv. C and in phase C of Pulv.-D motor. Discharge at conductor surface was discovered in phase A of Pulv. D motor. Slot discharges occurred in three phases of Pulv. E motor.

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Effect of Carbohydrate Sources in Phase I and Phase II Pig Starter Diets

  • Kim, I.B.;Allee, G.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1419-1424
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    • 2001
  • Previous research in our laboratory has demonstrated the importance of lactose in phase I and II pig starter diets. Two experiments were conducted to evaluate the use of a carbohydrate by-product (food by-products) as a replacement for lactose. In Exp. I, 120 weaned pigs ($14{\pm}2d$ and 5.65kg) were allotted in a randomized complete block design (RCBD) to 10 replications with four pigs per pen. This experiment evaluated three carbohydrate sources (lactose, carbohydrate by-product, and 50-50 blend of the carbohydrate by-product and lactose). The carbohydrate sources were added at 26% in the phase I diets and 15% in the phase II diets. Phase I diets contained 7.5% spray dried plasma protein (SDP). The phase I diets were fed from d 0 to 14 and the phase II diets from d 15 to 28. There were no significant differences between carbohydrate sources on pig performance in phase I. However, during phase II pigs fed the diet with lactose had an improved gain/feed ratio (G/F) (p=0.06) compared to pigs fed the carbohydrate by-product. For the entire 28 d trial ADG, ADFI and G/F were similar for the 50-50 blend and those fed lactose. Total replacement of lactose with the carbohydrate byproduct resulted in a reduced G/F (p=0.09). Exp. 2 used 100 weaned pigs ($17{\pm}2d$ and 4.75kg) with five replications with five pigs per pen. This experiment evaluated four carbohydrate treatments (lactose, carbohydrate by-products, 50-50 blend, and corn). All phase I diets contained 3.5% SDP with the carbohydrate sources included at 15%, and were fed d 0 to 14. The phase II diets contained 7.5% of the carbohydrate sources and were fed d 15 to 27. A common phase III diet was fed d 28 to 42. During all phases pigs fed com tended to have a lower ADG than pigs fed the other carbohydrate sources with the 50-50 blend resulting in the highest ADG. The results of both experiments suggest that this carbohydrate by-product can replace at least 50% of the lactose in phase I and phase II pig starter diets.

Embriological study of Viscera and Bowels on the view: Viscera and Bowels form Triple energizers to be five-viscera and six-bowels (오장오부(五藏五府)에서 삼초(三焦)를 형성(形成)하여 오장육부(五藏六府)가 되는 장부(藏府)의 발생학적(發生學的) 연구(硏究))

  • Kim, Kyoung-Shin;Lee, Tae-Kyoung;Kang, Jung-Soo;Kim, Byoung-Soo
    • Journal of Korean Medical classics
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    • v.22 no.4
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    • pp.55-66
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    • 2009
  • The formative procedure of five-viscera has been explained for the restriction[相克; 己勝] and the reverse restriction[相侮, 勝己] in five phase theory on the medical literatures from ancient times. In the formative procedure of five-viscera, it would seem that two theories are mutually contradictory. But this problem is solved in the view: As the upward, downward movement and the circulation progress, five-viscera and five-bowels develop. In brief on the formative procedure of human viscera and bowels, first, the circulation of five-viscera and five-bowels forms three phase of upper-middle-lower(fire-earth-water), and these phases generate Triple energizers[Samcho, 三焦], consequently it is to be five-viscera and six-bowels, to be formed 'Meridian and collateral[Gyeongnak, 經絡]' in that order. The triple energizers is situated in middle stage of formation of 'Vicera' and 'Meridian and collateral' on developing stage. It would be thought that Triple energizer meridian[Susoyangsamchogyeong, 手少陽三焦經] is formed in procedure of Meridian and collateral after formation of upper-middle-lower of the triple energizers.

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Precipitation of Icosahedral Qusicrystal Phase in Mg-Zn-Y(ZW61) alloy (Mg-Zn-Y(ZW61) 합금에서 Icosahedral 준결정상의 석출)

  • Kwak, Ho-Yeon;Lee, Kap-Ho
    • Korean Journal of Materials Research
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    • v.21 no.3
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    • pp.168-173
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    • 2011
  • Precipitation of the ordered icosahedral quasicrystal in Mg-6wt%Zn-1wt%Y alloy has been characterized by transmission electron microscopy observations. The lamellar-type icosahedral qusicrystal phases (I-phase) with the face-centered icosahedral (FCI) structure are observed in alloy after solution treatment at $550^{\circ}C$. In the alloy annealed at $400^{\circ}C$, polygon-shaped I-phases are observed in the ${\alpha}$-Mg matrix. The interfaces of the I-phase with the matrix are facetted and the facets are on five-fold and two- fold plane of the I-phase. The orientation relationship of the I-phase with the matrix is determined to be $[I5]_I//[001]_{Mg}$, $(2f)_I//(2\overline{1}0)_{Mg}$ and $[I2]_I//[311]_{Mg}$, $(5f)_I//(0\overline{1}1)_{Mg}$. The icosahedral grains are occasionally found to be twinned with one of the five-fold axis as the twin axis. The twin boundaries appear to be fairly straight and perpendicular to the fivefold twin axis. The icosahedral twin can be expressed as a rotation of $63.4^{\circ}$ or $116.62^{\circ}$ around two fold zone axis.