• Title/Summary/Keyword: initial state

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Design of Ohmic Contact RF MEMS Silicon Switch with High Isolation at High Frequencies (고주파에서 높은 신호 격리도를 갖는 접촉식 RF MEMS 스위치의 설계)

  • Lee, Yong-Seok;Jang, Yun-Ho;Kim, Jung-Mu;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1509_1510
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    • 2009
  • This paper presents the design and simulation results of ohmic contact RF MEMS silicon switch with a high isolation at high frequencies along with the position of a contact part, initial off-state and intermediate off-state including the state where a contact part is placed right over a signal line of coplanar waveguide (CPW). The ohmic contact part is connected with comb drives made of high resistivity single crystalline silicon. The released contact part is $30{\mu}m$ apart from the edge of signal line on the glass substrate along the lateral direction (x-direction) at initial off-state. The electrostatic force of the comb electrode creates the x-directional movement thus initial state is converted to the intermediate off-state. The initial off-state of the switch results in isolations of -31 dB, -24 dB and reflections of -0.45 dB, -0.67 dB at 50 GHz and 110 GHz, respectively. It shows the isolation degradation when the contact part moves right over the signal line of CPW like an initial off-state of a conventional MEMS switch. The isolations and reflections are -31 dB, -24 dB and -0.50 dB, -1.31 dB at 50 GHz and 110 GHz, respectively at the intermediate off-state.

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Error Analysis of Initial Fine Alignment for Non-leveling INS (경사각을 갖는 관성항법시스템 초기 정밀정렬의 오차 분석)

  • Cho, Seong-Yun
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.6
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    • pp.595-602
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    • 2008
  • In this paper, performance of the initial alignment for INS whose attitude is not leveled is investigated. Observability of the initial alignment filter is analyzed and estimation errors of the estimated state variables are derived. First, the observability is analyzed using the rank test of observability matrix and the normalized error covariance of the Kalman filter based on the 10-state model. In result, it can be seen that the accelerometer biases on horizontal axes are unobservable. Second, the steady-state estimation errors of the state variables are derived using the observability equation. It is verified that the estimates of the state variables have errors due to the unobservable state variables and the non-leveling tilt angles of a vehicle containing the INS. Especially, this paper shows that the larger the tilt angles of the vehicle are, the larger the estimation errors corresponding to the sensor biases are. Finally, it is shown that the performance of the 8-state model excepting the accelerometer biases on horizontal axes is better than that of the 10-state model in the initial alignment by simulation.

A Study on the Optimal User/Librarian Interface in Information Searching (정보탐색에 있어서 이용자/사서의 최적화 접속에 관한 연구)

  • Kim Sun-Ho
    • Journal of the Korean Society for Library and Information Science
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    • v.26
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    • pp.167-185
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    • 1994
  • The purpose of this study is to develop the optimal user/librarian interface in information searching. In order to achive the purpose, the 150 unskilled students as subjects have participated in the study. According to the change of the subjects' psychological information states by the access points within the library system, the subjects have been classified into the five types of model: the initial information state, the accepted identification information state, the bibliographic information state, the stack information state, and the location information state. Librarian's searching support is done for 10 minutes at the each access points. To develop the optimal user/librarian interface, the expected values of the models are calculated. The resultants are as follows: 1) The expected value of the initial information states model is 18.94: 2) The expected value of the accepted identification information model is 27.06: 3) The expected value of the bibliographic information state model is 27.06: 4) The expected value of the stack information state model is 22.38: 5) The expected value of the location information state model is 22.38. Those expected values are compared with each other. The model with the lowest expected value is chosen as the optimal user/librarian interface model. In the result, the user's initial information state model of the optimal user/librarian interface in information searching is developed. In order to search the information with the most effect, user must be interfaced with the librarian at his/her own initial information state.

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The Initial Magnetic Field Decay of the Superconducting Magnet in the Persistent Current Mode (초전도자석의 영구전류모드 운전시 초기자장감쇠)

  • 배준환;심기덕;권영길
    • Progress in Superconductivity and Cryogenics
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    • v.2 no.1
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    • pp.31-34
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    • 2000
  • this paper deals with the initial magnetic field decay for a large scale superconducting magnet e.g. NMR/MRI magnet. The high resolution image can not be obained during the periods of the initial field decay. It is known that all superconducting materials have the property of diamagnetism. This diamagnetism is usually explained with the concept of screening current. We assumed that the existence of the screening currebt. we assumed that the existence of the screening current makes the current distribution in the superconducting wire non-uniform. And the initial magnetic field decay is caused steady current state in the view of its pattern. The initial magnetic field decay is caused by the change of the current distribution between the energizing state and persistent current mode. in this paper the theoretical analysis for the current distributions has been introduced for each state. The experiments have been carried out to verify transport currents in order to veperiments, it small at the higher transport current.

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On the influence of polymer surface layer thickness on the adhesion of composite assembly. Differences between initial state and thermal ageing.

  • Benard, Q.;Fois, M.;Picard, C.;Grisel, M.
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.363-363
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    • 2006
  • Bonding of composite materials with an adhesive layer is one of the most promising alternatives to classical bonding techniques. The use of several surface treatments may greatly increase this adhesion behavior at the initial state. Then in order to see the influence of the thickness of polymer matrix on the adhesion of composite assembly, different surface treatment, which can reduce or increase this thickness, are used (peel ply, tear ply, excimer laser). The influence of this specific parameter is not only discussed at the initial state but also after thermal ageing of the whole bonded assembly. Results show that the best performances at the initial state are not obviously the best performances after ageing.

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Reinforcement learning Speedup method using Q-value Initialization (Q-value Initialization을 이용한 Reinforcement Learning Speedup Method)

  • 최정환
    • Proceedings of the IEEK Conference
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    • 2001.06c
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    • pp.13-16
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    • 2001
  • In reinforcement teaming, Q-learning converges quite slowly to a good policy. Its because searching for the goal state takes very long time in a large stochastic domain. So I propose the speedup method using the Q-value initialization for model-free reinforcement learning. In the speedup method, it learns a naive model of a domain and makes boundaries around the goal state. By using these boundaries, it assigns the initial Q-values to the state-action pairs and does Q-learning with the initial Q-values. The initial Q-values guide the agent to the goal state in the early states of learning, so that Q-teaming updates Q-values efficiently. Therefore it saves exploration time to search for the goal state and has better performance than Q-learning. 1 present Speedup Q-learning algorithm to implement the speedup method. This algorithm is evaluated. in a grid-world domain and compared to Q-teaming.

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A Study on the Initial Irreversible Capacity of Lithium Intercalation Using Gradually Increasing State of Charge

  • Doh, Chil-Hoon;Jin, Bong-Soo;Park, Chul-Wan;Moon, Seong-In;Yun, Mun-Soo
    • KIEE International Transactions on Electrophysics and Applications
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    • v.3C no.5
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    • pp.189-193
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    • 2003
  • Initial irreversible capacity (IIC) can be defined by means of the initial intercalation Ah efficiency (IIE) and the initial irreversible specific capacity at the surface (IICs) with the linear-fit range of the intercalation so as to precisely express the irreversibility of an electrode-electrolyte system. Their relationship was IIC = Qc - Q$_{D}$ = (IIE$^{-1}$ - 1) Q$_{D}$ + IICs in the linear-fit range of IIE. Here, Qc and Qd signify charge and discharge capacity, respectively, based on a complete lithium ion battery cell. Charge indicates lithium insertion to carbon anode. Two terms of IIE and IICs depended on the types of active materials and compositions of the electrode and electrolyte but did not change with charging state. In an ideal electrode-electrolyte system, IIE and IICs would be 100%, 0 mAh/g for the electrode and mAh for the cell, respectively. These properties can be easily obtained by the Gradual Increasing of State of Charge (GISOC).OC).

Time Optimal Control of Nuclear Reactor with Constraint on Power Overshoot (Overshoot에 구속조건을 갖는 원자여의 시간최적제어)

  • 곽은호
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.4
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    • pp.15-20
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    • 1975
  • The power overshoot is rises in the output during the transient period when the output of nuclear reactor is increased from the initial state to the desired target state and certain amount of constraint on power level is of primary importance for safety control of nuclear reactor. Therefore, the maximum principle is applied to this process control in transfering its power from the initial state(no, co) to the final target state(2no, 2co or 1.5no, 1.5co), adjusting the reactivity so that its overshoot is limited within the allowable constraint required. In this case, the switching points, switching times, optimal lima and optimal control reactivity are calculated.

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Complex Discrete Systems Graph Simulation

  • Kadirova, Delovar;Kadirova, Aziza
    • Journal of Multimedia Information System
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    • v.2 no.3
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    • pp.263-274
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    • 2015
  • The subject of this work is the complex discrete systems simulation special features with the aid of dynamic graph models. The proposed simulation technique allows to determine the ways for tasks solutions in terms of discrete systems analysis and synthesis of various complication: one-dimensional and multidimensional, steady and unstable, with the pulse elements abnormal operating mode and others. Often complex control systems analysis and synthesis task solutions, via classical approach comes out to be insolvent, because of the computational problems. The application of graph models allows to perform clear and strict characterization and computer procedures automation. The optimal controls synthesis algorithm presented in this paper, transferring the discrete system from target initial state to target final state within the minimum time, allows to consider the zero initial conditions systems, with the initial potential energy, with the control actions limitations and complex pulse elements operating mode.

Rotational State Distributions of I2(B) from Vibrational Predissociation of I2(B)-Ne

  • Cho, Sung-Sil;Sun, Ho-Sung
    • Bulletin of the Korean Chemical Society
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    • v.25 no.9
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    • pp.1397-1402
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    • 2004
  • The vibrational predissociation of triatomic, i.e., atom-diatom, van der Waals complexes in transient electronic excited state has been widely investigated. The predissociation rates or lifetimes are major concerns of the previous studies. Experimentally rotational state distributions of diatomic product are hardly investigated and few theoretical stuides on rotational state distributions have appeared in literature. In this work, choosing the frequently studied $I_2(B)-Ne$ complex as an example, we investigate the change of rotational state distributions of $I_2(B)-Ne$ produced from predissociation of the various initial states of $I_2(B)-Ne$. The present study on the rotational distributions indicates that rotational state distributions depend significantly on the predissociation energy and the van der Waals vibrational modes of $I_2(B)-Ne$. That is, the initial state dependency of rotational state distributions is extensively discussed.