• 제목/요약/키워드: moving reaction

검색결과 137건 처리시간 0.024초

가동차 위치에 따른 인덕턴스 변화와 Push/Pull 효과를 고려한 가동코일형 LOA의 동특성 (Dynamic Characteristics of Moving Coil Linear Oscillatory Actuator Considering the Variable Inductance and Push/pull Effects)

  • 정상섭;장석명
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제50권7호
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    • pp.307-314
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    • 2001
  • A moving coil linear oscillatory actuator is consisted of the NdFeB permanent magnets with high specific energy as the stator, a coil-wrapped nonmagnetic hollow rectangular structure and an iron core as a pathway for magnetic flux. The variation of mover position and the consequent changes of coil flux path affect the coil inductance, because coil flux leaks at the open region of LOA stator. The interaction between permanent magnet and armature field is to shift the airgap flux density variation due to the magnet alone by a certain amount. The unbalanced reciprocation force due to armature reaction field decreases the advantage of moving coil LOA, such as a high degree of linearity and controllability in the force ad motion control. This paper firstly describes the coil inductance, the deviation of flux density, and the unbalanced reciprocation force, which are derived form the permeance model of LOA. Secondly, the analytical method are verified using the 2D finite element method and tests. Finally, the dynamic simulation algorithm taking the armature reaction effect and variable inductance into account, is proposed and confirmed through the experiment.

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Identification of Reaction Mechanism to Produce High Quality Weld During Submerged Arc Welding

  • Kim, Jeong-Han;Kang, Kyong-Sik
    • 품질경영학회지
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    • 제21권2호
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    • pp.242-253
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    • 1993
  • The interpretation of the reaction mechanism is significant to produce the high quality welds and understand the welding processes. This investigation is important for the design of welding consumables and the selection of welding process parameters to develop the high quality welds. The objective of this study is to investigate the effect of electrochemical reactions on the transfer of alloy elements between slag and weld metal during submerged arc welding During submerged arc welding weld metal composition is shown to be controlled by two reaction mechanisms in four reaction zones. The responsible reaction mechanisms are thermochemical and electrochemical reactions. The possible reaction sites are the melted electrode tip, the detached droplet, the hot weld pool immediately below the moving electrode, and the cooling and solidifying weld pool behind the moving electrode. The possible reactions in submerged arc welding at different zones of the process is schematically shown in Figure 1.

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반경방향 순응기구를 갖는 스크롤 압축기의 동적 거동 (Dynamic behavior of a scroll compressor with radial compliance device)

  • 김현진;김재호;이진갑
    • 설비공학논문집
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    • 제10권1호
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    • pp.33-43
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    • 1998
  • Dynamic behavior of a scroll compressor has been investigated analytically. The equations of motion of moving elements of the scroll compressor such as the orbiting scroll, anti-rotation device, slider bush, and the crank shaft with eccentric crank pin have been set up. As the solutions of these equations, reaction forces between the moving elements, and also between the moving elements and the compressor frame have been calculated. The reaction forces from the moving elements to the frame are the unbalanced forces, which produce accelerations of the compressor body. These accelerations can be used as a measure of the compressor vibration. The major contributions to the unbalanced forces come from the orbiting movement of the orbiting scroll.

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Time-moving Metaphors and Ego-moving Metaphors: Which Is Better Comprehended by Taiwanese?

  • Huang, Hsin-Mei;Hsieh, Ching-Yu
    • 한국언어정보학회:학술대회논문집
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    • 한국언어정보학회 2007년도 정기학술대회
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    • pp.173-181
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    • 2007
  • This is a semantic pilot study which concentrates on how people in Taiwan process the temporal metaphors, ego-moving metaphor and time-moving metaphor. Motivated by the research of Gentner, Imai, and Boroditsky (2002) in which the English native speakers comprehend ego-moving metaphors faster than time-moving metaphors, the present study attempts to reexamine whether the faster reaction to ego-moving metaphors is shared by both the Chinese native speakers and EFL learners. To achieve the goals, 25 Chinese/English bilinguals are invited to be examined via the16 Chinese and 16 English test sentences. The recordings of their accuracy on each item are served as the databases used to compare with the study of Gentner, Imai, and Boroditsky (2002). The two finding presented here are: (1) when the subjects tested in their native language, Chinese, they process ego-moving metaphors better. (2) when tested in the foreign language, English, they conceptualize time-moving metaphors much better.

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Theoretical Studies on Phentl Group Migration of Protonated 1,2-Diphenyl Hydrazines

  • 김찬경;이인영;김장근;이익춘
    • Bulletin of the Korean Chemical Society
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    • 제21권5호
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    • pp.477-482
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    • 2000
  • Phenyl group migration within protonated 1,2-diphenyl hydrazines has been studied theoretically using the semi-empirical AM1 method. This reaction proceeds through a 3-membered cyclic transition state and requires high activation energy. In the reactant, there was no resonance stabilization for the moving Z-ring, however, hammett $p_Z^+$ values are large due to the direct involvement of the Z-ring inthe reaction, and the development of a negative charge on the reaction center gives them a posifive value. In the case of the non-moving ring, $p_Y^+$ values are small and negative owing to the smaller positive charge increase in the reaction center. The cross-interaction constant, $p_YZ^+$, was obtained from the activation enthalpies, using the multipe linear regression methdo, and the interaction between two substituents, Y and Z, is examined.

Three dimensional dynamic response of functionally graded nanoplates under a moving load

  • Hosseini-Hashemi, Shahrokh;Khaniki, Hossein Bakhshi
    • Structural Engineering and Mechanics
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    • 제66권2호
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    • pp.249-262
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    • 2018
  • In this paper, reaction of functionally graded (FG) thick nanoplates resting on a viscoelastic foundation to a moving nanoparticle/load is investigated. Nanoplate is assumed to be thick by using second order shear deformation theory and small-scale effects are taken into account in the framework of Eringen's nonlocal theory. Material properties are varied through the thickness using FG models by having power-law, sigmoid and exponential functions for material changes. FG nanoplate is assumed to be on a viscoelastic medium which is modeled using Kelvin-Voight viscoelastic model. Galerkin, state space and fourth-order Runge-Kutta methods are employed to solve the governing equations. A comprehensive parametric study is presetned to show the influence of different parameters on mechanical behavior of the system. It is shown that material variation in conjunction with nonlocal term have a significant effect on the dynamic deformation of nanoplate which could be used in comprehending and designing more efficient nanostructures. Moreover, it is shown that having a viscoelastic medium could play an important role in decreasing these dynamic deformations. With respect to the fresh studies on moving atoms, molecules, cells, nanocars, nanotrims and point loads on different nanosctructures using scanning tunneling microscopes (STM) and atomic force microscopes (AFM), this study could be a step forward in understanding, predicting and controlling such kind of behaviors by showing the influence of the moving path, velocity etc. on dynamic reaction of the plate.

Simulated Moving Bed Reactor(SMBR)의 원리 (Principles of Simulated Moving Bed Reactor(SMBR))

  • 송재룡;김진일;구윤모
    • Korean Chemical Engineering Research
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    • 제49권2호
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    • pp.129-136
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    • 2011
  • SMB 공정은 주로 4개의 구역으로 나뉘어지는 다수의 크로마토그래피 컬럼으로 구성된다. 이러한 특성은 회분식 크로마토그래피 공정보다 우수한 이성분계 물질의 연속적인 분리를 구현한다. SMB는 회분식 크로마토그래피에 비해 연속성 및 높은 생산성과 순도로 목적물질을 분리해 낼 수 있는 장점을 갖는다. 경제적이며 효율적인 공정의 운용을 위해 반응과 회수를 결합시키는 연구가 보고되고 있으며, 이와 같은 연구 중 SMBR은 연속분리공정인 SMB와 반응기가 결합된 공정이다. 다양한 반응을 적용한 SMBR에 대해 많은 연구가 진행되고 있으며, 촉매반응, 효소반응, 이온 교환 수지를 통한 화학반응이 주를 이루고 있다. 초기의 SMBR은 촉매를 사용한 고정층의 형태이며, 유동성 효소를 사용하는 SMBR, 고정화 효소를 사용하는 SMBR, 반응구역과 흡착구역이 분리되어 있는 SMBR순으로 발전하였다. 공정 설계에 있어서 필수적인 모델링 및 최적화를 위하여 대류현상만을 고려한 간단한 기법이 있지만, 실제 물질거동을 설명하기 위해서는 축 방향 분산이나 물질전달 저항을 고려한 복잡한 해석을 필요로 한다. SMBR같이 반응과 분리가 결합된 공정의 경우 설비의 간소화를 통한 시설비용의 축소뿐 아니라 가역반응평형의 극복을 통해 물질의 순도와 수율을 향상시킬 수 있는 장점이 있다.

육계의 성비가 행동 및 복지지표에 미치는 영향 (Influence of Sex Ratio on Behavior and Welfare Indexes in Broiler Chicken)

  • 손장호
    • 한국가금학회지
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    • 제37권1호
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    • pp.43-49
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    • 2010
  • 본 연구에서는 육계의 성비가 행동 및 복지지표에 미치는 영향에 대해서 조사하였다. 암수의 성비를 0:100 (T1), 25:75(T2), 50:50 (T3), 75:25 (T4) 및 100:0 (T5)의 5 처리를 하여서 4주간 조사하였다. 처리구에서 전체 행동 중 resting 행동 빈도가 74.4% 이상으로 가장 많이 차지하였다. 그 외 pecking 행동이 5.39∼23.07%, standing 행동이 1.78∼24.75%, moving 행동이 0.59∼11.46%로 나타났다. Pecking, standing resting 및 moving 행동 빈도는 성비 및 암수간에 유의한 차이는 인정되지 않았다(P>0.05). 그러나 pecking, resting 및 moving 행동 빈도는 일령의 변화에 따라서 유의한 차이가 인정되었다(P<0.05). Gait, foot pad 및 hock burn score는 성비의 차이에 따른 영향을 받지 않았지만, 모든 처리구에서 수컷보다 암컷에서 감소하는 경향이 나타났다. 21일령과 35일령에서의 발톱의 길이는 성비에 따라서, 또는 암수간에 차이는 인정되지 않았다. TI-reaction은 21령이 35일령보다, 암컷이 수컷보다 낮아지는 경향이 인정되었다. 본 연구에서 T4 처리구의 hock burn score, 발톱의 길이 및 TI-reaction이 다른 처리구보다 낮아지는 경향이 인정되었다. 결론적으로 육계를 암수 혼합 사육할 때, 암수의 성비는 육계의 복지지표에 영향을 미칠 가능성이 생각된다.

반동도에 따른 증기터빈의 설계 및 성능해석 (Design and Performance Analysis of Steam Turbine for Variations of Degree of Reaction)

  • 신중하;이근식
    • 대한기계학회논문집B
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    • 제35권12호
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    • pp.1391-1398
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    • 2011
  • 반동도에 따른 증기터빈의 설계 및 성능 해석을 컴퓨터 시뮬레이션으로 수행하였다. 깃 각도와 출구면적, 노즐면적과 같은 설계변수들과 터빈동력, 선도효율, 축방향 추력과 같은 성능변수들을 반동도에 따라 나타내었다. 추가적인 설계 및 성능변수에 대한 정보를 제공하기 위하여, 깃 각도와 터빈동력, 선도효율, 축방향 추력과 같은 주된 설계 및 성능변수들을 유동계수(주속도에 대한 축방향속도)의 함수로 제시하였다. 터빈동력, 선도효율을 최대로 하는 반동도 및 유동계수가 존재함이 밝혀졌으며, 반동도가 증가함에 따라 동익의 깃 형상은 대칭형으로부터 많이 벗어남을 보여주었다.

Response of passively loaded pile groups - an experimental study

  • Al-abboodi, Ihsan;Sabbagh, Tahsin Toma;Al-salih, Osamah
    • Geomechanics and Engineering
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    • 제20권4호
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    • pp.333-343
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    • 2020
  • Preventing or reducing the damage impact of lateral soil movements on piled foundations is highly dependent on understanding the behavior of passive piles. For this reason, a detailed experimental study is carried out, aimed to examine the influence of soil density, the depth of moving layer and pile spacing on the behavior of a 2×2 free-standing pile group subjected to a uniform profile of lateral soil movement. Results from 8 model tests comprise bending moment, shear force, soil reaction and deformations measured along the pile shaft using strain gauges and others probing tools were performed. It is found that soil density and the depth of moving layer have an opposite impact regarding the ultimate response of piles. A pile group embedded in dense sand requires less soil displacement to reach the ultimate soil reaction compared to those embedded in medium and loose sands. On the other hand, the larger the moving depth, the larger amount of lateral soil movement needs to develop the pile group its ultimate deformations. Furthermore, the group factor and the effect of pile spacing were highly related to the soil-structure interaction resulted from the transferring process of forces between pile rows with the existing of the rigid pile cap.