• Title/Summary/Keyword: Three-loop

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Enumeration of axial rotation

  • Yoon, Yong-San
    • Advances in biomechanics and applications
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    • v.1 no.2
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    • pp.85-93
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    • 2014
  • In this paper, two procedures of enumerating the axial rotation are proposed using the unit sphere of the spherical rotation coordinate system specifying 3D rotation. If the trajectory of the movement is known, the integration of the axial component of the angular velocity plus the geometric effect equal to the enclosed area subtended by the geodesic path on the surface of the unit sphere. If the postures of the initial and final positions are known, the axial rotation is determined by the angular difference from the parallel transport along the geodesic path. The path dependency of the axial rotation of the three dimensional rigid body motion is due to the geometric effect corresponding to the closed loop discontinuity. Firstly, the closed loop discontinuity is examined for the infinitesimal region. The general closed loop discontinuity can be evaluated by the summation of those discontinuities of the infinitesimal regions forming the whole loop. This general loop discontinuity is equal to the surface area enclosed by the closed loop on the surface of the unit sphere. Using this quantification of the closed loop discontinuity of the axial rotation, the geometric effect is determined in enumerating the axial rotation. As an example, the axial rotation of the arm by the Codman's movement is evaluated, which other methods of enumerating the axial rotations failed.

Evaluating genetic diversity and identifying priority conservation for seven Tibetan pig populations in China based on the mtDNA D-loop

  • Ge, Qianyun;Gao, Caixia;Cai, Yuan;Jiao, Ting;Quan, Jinqiang;Guo, Yongbo;Zheng, Wangshan;Zhao, Shengguo
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.12
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    • pp.1905-1911
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    • 2020
  • Objective: Tibetan pigs, an excellent species unique to China, face serious threats, which in turn affects the development and utilization of the outstanding advantages of plateau hypoxia adaptability and reduces their genetic diversity. Therefore, a discussion of measures to conserve this genetic resource is necessary. The method, based on genetic diversity, genetic divergence and total genetic contribution rate of population, reflects the priority conservation order and varies depending on the three different purposes of conservation. Methods: We analyzed mitochondrial DNA control region (D-loop) variation in 1,201 individuals from nine Tibetan pig populations across five provinces and downloaded 564 mtDNA D-loop sequences from three indigenous pig breeds in Qinghai, Sichuan, and Yunnan Provinces distributed near the Tibetan pigs. Results: We analyzed three different aspects: Changdu Tibetan pigs have the highest genetic diversity, and from the perspective of genetic diversity, the priority conservation is Changdu Tibetan pigs. Hezuo Tibetan pigs have the highest genetic contribution, so the priority conservation is Hezuo Tibetan pigs in the genetic contribution aspect. Rkaze Tibetan pigs were severely affected by indigenous pig breeds, so if considering from the perspective of introgression, the priority conservation is Rkaze Tibetan pigs. Conclusion: This study evaluated genetic diversity and comprehensively assessed conservation priority from three different aspects in nine Tibetan pig populations.

The Three-Loop Pulley Repair of Complete Achilles Tendon Ruptures in Two Hunting Dogs (사냥개에서 Three-Loop Pulley 봉합법을 이용한 아킬레스건 완전단열의 수복 2례)

  • Lim Sang-Woong;Cho Ki-Rae;Kim Jong-Min;Cho Kyu-Man;Han Tae-Sung;Lee Jae-Yeong;Kim Gon-Hyung;Choi Seok-Hwa
    • Journal of Veterinary Clinics
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    • v.23 no.1
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    • pp.81-85
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    • 2006
  • Complete ruptures of the Achilles tendon were repaired in two hunting dogs of a 3-year-old, 20 kg and a 4-year-old, 14 kg with non weight bearing lameness. Both dogs were injured by wild animals and the skin defect was showed on the caudal surface of the right limb. Surgical repair involved the attachment of the ruptured tendon with a three-loop pulley method, using nonabsorbable suture materials. After surgical procedure, a bivalved cast was applied and maintained for 6 weeks. Exercise was restricted for 2 weeks more before gradually returned to normal. Gait and standing posture of dogs were returned to normal during the follow-up of 10 weeks.

A Fundamental Study on the Electron Behavior and Optimum Condition for the Formation of a Neutral Loop Discharge Plasma (Neutral Loop Discharge 플라즈마의 전자거동과 최적조건에 관한 기초적 연구)

  • Sung, Youl-Moon;Kim, Jong-Kyung;Park, Chung-Hoo
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.6
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    • pp.281-287
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    • 2001
  • In order to obtain guidelines for design and operation of a new plasma source by a magnetic neutral loop discharge(NLD), the electron behavior was studied experimentally and numerically. Experimentally, the magnetic field gradient was changed over a wide range, and it was found that there existed an optimum value for efficient plasma production. Analyses of the electron behavior were performed using a model that included effects of a three dimensional electromagnetic field configuration considering the spatial decay of the electric field, and the limitation to the motion of electron caused by the existence of walls and thus electron loss at wall surfaces. These three dimensional factors were found to explain the existence of the optimum magnetic field gradient. It was shown that the L dependence of the plasma production efficiency was firstly decided by the finite decay length of the electric field strength, which was further modified by electron elastic collisions with neutral atoms which drove the electron to walls. The latter effect tends to reduce the optimum value of L.

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A Presentation on the Manual Hydraulic Calculation Method of the Loop Type Fire Sprinkler System (Loop형 스프링클러 설비의 수리계산 방법에 대한 제시)

  • Jeong, Keesin
    • Fire Science and Engineering
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    • v.29 no.1
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    • pp.73-79
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    • 2015
  • There are three kinds of design method of the fire sprinkler systems. Grid type is connected all branch as a trapezoid. Loop type is connected cross-mains like circle. The last one is a tree type most commonly used. Grid type needs computer program to calculate the friction loss and flow rate apart from very simple form. In loop type, manual calculation is possible. Design engineer can draw up and calculate the demands without computer program. Because water supplies two direction in loop type, friction loss is smaller than tree type. Water distribution in operation area is uniform because of the small differences of sprinklers discharge pressure. Loop type is superior to tree type in respect of total pressure and flow rate. Using the small diameter pipe, the labor and construction cost will be decreased in the end. Loop type sprinkler design is rarely laid out because design engineers don't know the method. This paper is intended to inform that the loop type is better than the tree type in performance and economic point of view. And also this paper intend to use the loop type easily and widely.

로켓 모션테이블 실시간 모의시험

  • Sun, Byung-Chan;Park, Yong-Kyu;Choi, Hyung-Don;Cho, Gwang-Rae
    • Aerospace Engineering and Technology
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    • v.3 no.1
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    • pp.170-178
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    • 2004
  • This paper deals with six degree-of-freedom HILS(hardware-in-the-loop-simulation) of KSR-III rocket using a TAFMS(three axis flight motion simulator). This TAFMS HILS test is accomplished before main HILS tests in order to verify the control stability in the presence of TAFMS dynamic effects. The TAFMS HILS test includes initial attitude holding tests for INS initial alignment procedures, timer synchronization tests with an auxiliary lift-off signal, real-time calibration tests using an external thermal recorder, open-loop TAFMS operating tests, and final closed-loop TAFMS HILS tests using the TAFMS attitude measurements as inputs to the closed control loop. The HILS tests are accomplished for several flight conditions composed with nominal flight condition, TWD effect added condition, slosh modes and/or bending modes existing condition, and windy condition, etc.

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Complete mitochondrial genome sequence of Tosa-Jidori sheds light on the origin and evolution of Japanese native chickens

  • Osman, Sayed A.M.;Nishibori, Masahide;Yonezawa, Takahiro
    • Animal Bioscience
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    • v.34 no.6
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    • pp.941-948
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    • 2021
  • Objective: In Japan, approximately 50 breeds of indigenous domestic chicken, called Japanese native chickens (JNCs), have been developed. JNCs gradually became established based on three major original groups, "Jidori", "Shoukoku", and "Shamo". Tosa-Jidori is a breed of Jidori, and archival records as well as its morphologically primitive characters suggest an ancient origin. Although Jidori is thought to have been introduced from East Asia, a previous study based on mitochondrial D-loop sequences demonstrated that Tosa-Jidori belongs to haplogroup D, which is abundant in Southeast Asia but rare in other regions, and a Southeast Asian origin for Tosa-Jidori was therefore suggested. The relatively small size of the D-loop region offers limited resolution in comparison with mitogenome phylogeny. This study was conducted to determine the phylogenetic position of the Tosa-Jidori breed based on complete mitochondrial D-loop and mitogenome sequences, and to clarify its evolutionary relationships, possible maternal origin and routes of introduction into Japan. Methods: Maximum likelihood and parsimony trees were based on 133 chickens and consisted of 86 mitogenome sequences as well as 47 D-loop sequences. Results: This is the first report of the complete mitogenome not only for the Tosa-Jidori breed, but also for a member of one of the three major original groups of JNCs. Our phylogenetic analysis based on D-loop and mitogenome sequences suggests that Tosa-Jidori individuals characterized in this study belong to the haplogroup D as well as the sub-haplogroup E1. Conclusion: The sub-haplogroup E1 is relatively common in East Asia, and so although the Southeast Asian origin hypothesis cannot be rejected, East Asia is another possible origin of Tosa-Jidori. This study highlights the complicated origin and breeding history of Tosa-Jidori and other JNC breeds.

Microbiologically Induced Corrosion of Three Tubular Materials

  • Mukadam, S.;Al-Hashem, A.
    • Corrosion Science and Technology
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    • v.14 no.6
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    • pp.267-272
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    • 2015
  • The performance of three tubular materials (C-90, L-80, and N-80) was evaluated in a synthetic brine inoculated with sulfate-reducing bacteria (SRB) in the absence and presence of biocides. A flow loop was used in the evaluation of the three alloys. Morphological examination of the alloy surfaces after exposure to SRB and after biocide treatment was performed by scanning electron microscopy (SEM) to determine the nature of any localized corrosion. The SE images of the coupon samples showed a marked difference between the biocide-treated and untreated samples. Small pits were observed on the ultrasonically cleaned surfaces of the three alloys after exposure to SRB. The biocide treatment reduced the number of SRB on the surfaces of the alloys. Results indicated that C-90 and L-80 alloys exhibited better MIC resistance than N-80 under the conditions used in this study.

Assessment of Three-Phase Actuated Signal Operation at Diamond Interchanges (다이아몬드 인터체인지의 3 현시 신호운영 평가)

  • 이상수
    • Proceedings of the KOR-KST Conference
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    • 2002.02a
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    • pp.143-159
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    • 2002
  • The performance of two single-barrier three-phase actuated control systems at diamond interchanges was evaluated for various traffic conditions. To emulate the actuated signal control, hardware-in-the-loop system combined with CORSIM simulation program was used. Two performance measures, average delay and total stops, were used for the evaluation process. Results showed that the two three-phase systems gave similar performance in terms of average delay, but not stops. The delay performance of each phasing system was generally dependent on the traffic pattern and ramp spacing. The total stops decreased as the spacing increased, and it was the most sensitive variable that can differentiate between the two three-phase systems. It was also shown that the hardware-in-the-loop control could provide a good method to overcome the limitations of current simulation technology.

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Fourier-Based PLL Applied for Selective Harmonic Estimation in Electric Power Systems

  • Santos, Claudio H.G.;Ferreira, Reginaldo V.;Silva, Sidelmo Magalhaes;Cardoso Filho, Braz J.
    • Journal of Power Electronics
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    • v.13 no.5
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    • pp.884-895
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    • 2013
  • In this paper, the Fourier-based PLL (Phase-locked Loop) is introduced with a new structure, capable of selective harmonic detection in single and three-phase systems. The application of the FB-PLL to harmonic detection is discussed and a new model applicable to three-phase systems is introduced. An analysis of the convergence of the FB-PLL based on a linear model is presented. Simulation and experimental results are included for performance analysis and to support the theoretical development. The decomposition of an input signal in its harmonic components using the Fourier theory is based on previous knowledge of the signal fundamental frequency, which cannot be easily implemented with input signals with varying frequencies or subjected to phase-angle jumps. In this scenario, the main contribution of this paper is the association of a phase-locked loop system, with a harmonic decomposition and reconstruction method, based on the well-established Fourier theory, to allow for the tracking of the fundamental component and desired harmonics from distorted input signals with a varying frequency, amplitude and phase-angle. The application of the proposed technique in three-phase systems is supported by results obtained under unbalanced and voltage sag conditions.