• 제목/요약/키워드: attractive force

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The Isosteric Heats of Adsorption of Amines on Paraffin and Polyethyleneglycol

  • Sohn Jong Rack;Kim, Jong Taik
    • Journal of the Korean Chemical Society
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    • v.16 no.4
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    • pp.208-213
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    • 1972
  • Isostric heats of adsorption of amines on paraffin and polyethyleneglycol were measured by gas chromatography. Value with polyethyleneglycol were significantly higher than those with paraffin due to the N-H...O bonding. The contribution of C-H...O bonding to the isosoteric heats of adsorption was negligible. The additional heats of adsorption observed as the sample size increased also increased as the number of amino hydrogen atoms decreased. This tendency was more significant with polyethyleneglycol indicating that strong directing force of amino hydrogen of primary and secondary amines to the surface hinder lateral attractive interaction which could be favored with free orientation.

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On navigation strategy of multiple autonomous mobile robots in a specified domain

  • Lee, Seog-Gyu
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1071-1076
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    • 1990
  • This paper proposes a navigation strategy of multiple autonomous mobile robots with communication within a specified space. Assuming that each robot has complete detectability with finite range, simple navigation strategy is derived by introducing repulsive forces between robots and attractive force between a robot and its goal point analogous to those between electric charges. When a robot is close to its goal point, a pseudo-domain based on the distance between the closest point of the domain boundary and the goal point is proposed to enhance its convergence to the goal state. This paper concludes with the results of computer simulation studies on the dynamic behavior of multiple interacting robots with the proposed navigation strategy.

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A study on the global planarization characteristics in end point stage for device wafers (다바이스 웨이퍼의 평탄화와 종점 전후의 평탄화 특성에 관한 연구)

  • 정해도;김호윤
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.12
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    • pp.76-82
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    • 1997
  • Chemical mechanical polishing (CMP) has become widely accepted for the planarization of multi-interconnect structures in semiconductor manufacturing. However, perfect planarization is not so easily ahieved because it depends on the pattern sensitivity, the large number of controllable process parameters, and the absence of a reliable process model, etc. In this paper, we realized the planarization of deposited oxide layers followed by metal (W) polishing as a replacement for tungsten etch-back process for via formation. Atomic force microscope (AFM) is used for the evaluation of pattern topography during CMP. As a result, AFM evaluation is very attractive compared to conventional methods for the measurment of planarity. mOreover, it will contribute to analyze planarization characteristics and establish CMP model.

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Optimal Design of Electro-Permanent Magnet Lifter Using Improved Auto-Tuning Niching Genetic Algorithm (개선된 Auto-Tuning 니칭 유전 알고리즘을 이용한 영전자식 권상기의 최적 설계)

  • Lee, Bum-Joo;Seo, Jang-Ho;Kwak, Sang-Yeop;Lee, Sang-Yeop;Jung, Hyun-Kyo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.5
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    • pp.783-788
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    • 2008
  • This paper presents the mechanism of the machine and the numerical result of attractive force in the Electro-Permanent Magnet Lifter (EPML) and an improved niching Genetic Algorithm (GA) applying the concept of auto-tuning and detecting traces. Population size and both (right and left) niche radii of each peak in an asymmetrical objective function can be determined automatically. The validity of the proposed method is verified by simulation results.

Design Parameter Deduction for Slotless Permanent Magnet Synchronous Motor/Generator (슬롯리스 영구자석 동기 전동/발전기를 위한 설계변수 도출)

  • Jang, Seok-Myeong;Lee, Un-Ho;You, Dae-Joon;Ko, Kyoung-Jin;Lee, Jung-Pill
    • Proceedings of the KIEE Conference
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    • 2008.10c
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    • pp.53-55
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    • 2008
  • In high speed applications, the slotless permanent magnet(PM) motors appear an attractive solution, being almost insensitive to magneto-motive force harmonics and to pulse width modulation(PWM) current ripple and exhibiting lower stator iron losses and rotor losses (significant with square wave current control). So, this paper deals with methods for design of permanent magnet synchronous motor/generator.

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Effects of the Interaction between Intercalant and Matrix Polymer in Preparation of Clay-dispersed Nanocomposite

  • Ko, Moon-Bae;Kim, Jyunkyung;Choe, Chul-Rim
    • Macromolecular Research
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    • v.8 no.3
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    • pp.120-124
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    • 2000
  • Clay-dispersed nanocomposites have been prepared by simple melt-mixing of two components, styrenic polymers with different content of functional groups and two different organophilic clays (Cloisite(R) 25A and Cloisite(R)30A) with a twin screw extruder. Dispersibility of 10-$\AA$-thick silicate layers of clay in the hybrid was investigated by using an X-ray diffraction method and a transmission electron microscope. It was found that if the interaction force between intercalant and matrix polymer is attractive, the matrix polymer intercalates more rapidly into the gallery of silicate layers. The faster intercalation of matrix polymer leads to the better dispersibility of silicate layers in the matrix polymer.

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The Synthesis of Reactive Dichloro-s-triazinyl Anionic Agent for Cellulosic Fibers and its Application (셀룰로오스 섬유용 반응형 디클로로트리아진계 음이온화제의 합성 및 응용)

  • 김태경;윤석한;임용진;손영아
    • Textile Coloration and Finishing
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    • v.15 no.5
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    • pp.294-300
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    • 2003
  • The anionic agent containing dichloro-s-triazinyl reactive group was synthesized and applied to the cotton fabrics to introduce covalent bonds. This attempt was expected to improve the affinities of cationic compounds, such as cationic dyes, chitosan, quaternary ammonium antimicrobial agents and metal ions, by the electrostatic attractive force. As expected, the anionic agent was reacted with cotton fabrics at room temperature. In order to examine the adsorptivity of the cationic compounds on to the anionized cotton fabrics, firstly a cationic dye(C. I. Basic Violet 7) was applied. The color strength of the dyeing of anioized cotton fabric was highly increased comparing to that of untreated fabric.

Sliding Mode Control for an Active Magnetic Bearing System (능동자기베어링계를 위한 슬라이딩모드 제어)

  • Kang, Min-Sig
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.12
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    • pp.82-88
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    • 2008
  • This paper describes an application of sliding mode control to an active magnetic bearing(AMB) system. A sliding mode control is robust to model uncertainties and external disturbances. To ensure the authority of sliding mode control, model parameter uncertainties caused from linearization of electro-magnetic attractive force are analyzed and a domain of parameter uncertainties in which reachability to sliding surface is guaranteed is derived. The validity of the analysis is illustrated along with some simulation examples.

Device Wafer의 평탄화와 AFM에 의한 평가

  • 김호윤;정해도
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.167-171
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    • 1996
  • Chemical mechanical polishing (CMP) has become widely accepted for the planarization of multi-interconnect structures in semiconductor manufacturing. However, perfect planarization is not so easily achieved because it depends on the pattern sensitivity, the large number of controllable process parameters, and the absence of a reliable process model, etc. In this paper, we realized the planarization of deposited oxide layers followed by metal (W) polishing as a replacement for tungsten etchback process for via formation. Atomic force microscope (AFM) is used for the evaluation of pattern topography during CMP. As a result, AFM evaluation is very attractive compared to conventional methods for the measurement of planarity. Moreover, it will contribute to analyze planarization characteristics and establish CMP model.

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Model on the electro-magnetic characteristics of elastic ferromagnetic materials with vibrationg gap (탄성 고투자율 자성체의 공극진동에 따른 전자기 특성에 관한 모델)

  • 김대수;김왕곤;홍진웅
    • Electrical & Electronic Materials
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    • v.9 no.9
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    • pp.891-899
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    • 1996
  • A model for predicting the characteristics of elastic ferromagnetic materials having a moving gap was presented. Based on the model parameters concerning behavior of material, such as the instantaneous field intensity, attractive force between the poles, length of gap, and the induced current/ emf in the circuit can be determined from the numerical integrations of the governing equations derived. From the results of the model it is found that when dc emf is imposed on the circuit the current sharply rise and fall for very short duration then stabilize at extremely low level which depends mainly on elasticity, permeabilities and ratio of resistivity. Subsequently output emf is shown stabilized at constant value which depends on the previous parameters as well as the resistivity ratio of primary to secondary circuit after sufficient progress of time.

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