• Title/Summary/Keyword: bond model

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MODEL BASED DIAGNOSTICS FOR A GEARBOX USING INFORMATION THEORY

  • Choi, J.;Bryant, M.D.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.459-460
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    • 2002
  • This article discusses a diagnostics method based on models, and information theory. From an extensive system dynamics bond graph model of a gearbox [1], simulated were various cases germane to this diagnostics approach, including the response of an ideal gearbox, which functions perfectly to designer's specifications, and degraded gearboxes with tooth root cracking. By comparing these cases and constructing a signal flow analogy between the gearbox and a communication channel, Shannon' s information theory [2], including theorems, was applied to the gearbox to assess system health, in terms of ability to function.

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CLINICAL CONSIDERATION OF INDIRECT BONDING TECHNIQUE (INDIRECT BONDING TECHNIQUE에 대한 고찰)

  • Lee, Kyung Hwan;Kim, Sang Cheol
    • The korean journal of orthodontics
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    • v.19 no.2
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    • pp.155-163
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    • 1989
  • Indirect bonding is done by placing the brackets on a model in the laboratory and using a template or tray to transfer the laboratory positioning to the teeth. The advantages of this technique are 1. decreased chair time 2. less patient discomfort 3. accuracy of a attachment placement 4. good adaptation of attachment to tooth contour 5. occlusal relationship of brackets and opposing teeth can be checked The disadvantages of the technique are 1. complex laboratory procedure 2. sometimes difficult on very short clinical crowns 3. teeth with crowns, large buccal restoration will not bond 4. may not be fitted close, if poor adaptation 5. likely to be disturbed setting Several indirect bonding techniques have proved reliable in clinical practice. However, they differ in the way the brackets are attached temporarily to the model, the type of transfer tray or other mechanism used, the adhesive or sealant employed, whether segmented or full bonding used, and the way the transfer is removed so as not to exert excessive force on a still maturing bond.

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A comparative Study of ARIMA and Neural Network Model;Case study in Korea Corporate Bond Yields

  • Kim, Steven H.;Noh, Hyunju
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1996.10a
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    • pp.19-22
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    • 1996
  • A traditional approach to the prediction of economic and financial variables takes the form of statistical models to summarize past observations and to project them into the envisioned future. Over the past decade, an increasing number of organizations has turned to the use of neural networks. To date, however, many spheres of interest still lack a systematic evaluation of the statistical and neural approaches. One of these lies in the prediction of corporate bond yields for Korea. This paper reports on a comparative evaluation of ARIMA models and neural networks in the context of interest rate prediction. An additional experiment relates to an integration of the two methods. More specifically, the statistical model serves as a filter by providing estimtes which are then used as input into the neural network models.

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Bending characteristics of corroded reinforced concrete beam under repeated loading

  • Fang, Congqi;Yang, Shuai;Zhang, Zhang
    • Structural Engineering and Mechanics
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    • v.47 no.6
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    • pp.773-790
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    • 2013
  • Bending behaviors of corroded reinforced concrete (RC) beams under repeated loading were investigated experimentally. A total of twenty test specimens, including four non-corrosion and sixteen corrosion reinforced concrete beams, were prepared and tested. A numerical model for flexural and cracking behaviors of the beam under repeated loading was also developed. Effects of steel corrosion on reinforced concrete beams regarding cracking, mid-span deflection, stiffness and bearing capacity of corroded beams were studied. The impact of corrosion on bond strength as the key factor was investigated to develop the computational model of flexural capacity. It was shown from the experimental results that the bond strength between reinforcement and concrete had increased for specimen of low corrosion levels, while this effect was changed when the corrosion level was higher. It was indicated that the bearing capacity of corrosion beam increased even at a corrosion level of about 5%.

The Pricing of Corporate Common Stock By OPM (OPM에 의한 주식가치(株式價値) 평가(評價))

  • Jung, Hyung-Chan
    • The Korean Journal of Financial Management
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    • v.1 no.1
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    • pp.133-149
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    • 1985
  • The theory of option pricing has undergone rapid advances in recent years. Simultaneously, organized option markets have developed in the United States and Europe. The closed form solution for pricing options has only recently been developed, but its potential for application to problems in finance is tremendous. Almost all financial assets are really contingent claims. Especially, Black and Scholes(1973) suggest that the equity in a levered firm can be thought of as a call option. When shareholders issue bonds, it is equivalent to selling the assets of the firm to the bond holders in return for cash (the proceeds of the bond issues) and a call option. This paper takes the insight provided by Black and Scholes and shows how it may be applied to many of the traditional issues in corporate finance such as dividend policy, acquisitions and divestitures and capital structure. In this paper a combined capital asset pricing model (CAPM) and option pricing model (OPM) is considered and then applied to the derivation of equity value and its systematic risk. Essentially, this paper is an attempt to gain a clearer focus theoretically on the question of corporate stock risk and how the OPM adds to its understanding.

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Performance Investigation of a Continuously Variable ER Damper for Passenger Vehicles (승용차용 연속가변 ER댐퍼의 성능연구)

  • Kim, K.S.;Chang, E.;Choi, S.B.;Cheong, C.C.;Suh, M.S.;Yeo, M.S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.3 no.6
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    • pp.69-77
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    • 1995
  • This paper presents performance investigation of a continuously variable ER(Electro-Rheological) damper for passenger vehicles. A dynamic model of the damper is formulated by incorporating electric field-dependent Bingham properties of the ER fluid. The Bingham properties are experimentally obtained through Couette type electroviscous measurement with respect to two different particle concentrations. The governing equation of the hydraulic model treating three components of fluid resistances;electrode duct flow, check valve flow and piston gap flow, is achieved via the bond graph method. A prototype ER damper is then designed and manufactured on the basis of parameter analysis. The damping forces of the system are experimentally evaluated by changing the intensity of the electric field, the particle concentration and the electrode gap.

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Study on the Position Control System of the Float Chamber using Air Control (부양체 수중 위치제어에 관한 연구)

  • Hur, J.G.;Kim, T.H.;Yang, K.U.
    • 유공압시스템학회:학술대회논문집
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    • 2010.06a
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    • pp.75-80
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    • 2010
  • The paper is that study method to reduce bad influence that act to the floating fish cage by effect of environment in sea. Fish cage is controlled buoyancy using air control. According to marine environment, it is descend automatically to set-up depth and rise on the surface of the sea. The paper is the preceding research for a practical application. The fish cage simplified with the spherical float body. Then a control algorithm and a program developed by the experiment. And we did modelling by bond graph technique, and controlled by the practical reference model for PID control.

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Nonlinear Analysis of RC Columns under Cyclic Loading Based on Moment-Curvature Relationship (반복하중을 받는 RC기둥의 비선형 해석을 위한 모멘트-곡률 관계의 개발)

  • 곽효경;김선필
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2002.04a
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    • pp.3-11
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    • 2002
  • A moment-curvature relationship to simulate the behavior of reinforced concrete (RC) columns under cyclic loading is introduced. Unlike previous moment-curvature models and the layered section approach, the unposed model takes into account the bond-slip effect by using a monotonic moment-curvature relationship constructed on the basis of the bond-slip relation and corresponding equilibrium equation at each nodal point. In addition, the use of curved unloading and reloading branches inferred from the stress-strain relation of steel gives more exact numerical result. The pinching enact caused by axial force is considered with an assumption that the absorbing energy corresponding to any deformation level maintains constant regardless of the magnitude of applied axial force. The advantages of the proposed model, comparing tn layered section approach, may be on the reduction in calculation time and memory space in case of its application to large structures.. Finally, correlation studies between analytical results and experimental studies are conducted to establish the validity of the proposed mood.

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A Functional Representation of the Potential Energy Surface of Non-Identical $S_N2$ Reaction: F- … $CH_3Cl \rightarrow FCH_3$ … Cl-

  • 김정섭;김영훈;노경태;이종명
    • Bulletin of the Korean Chemical Society
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    • v.19 no.10
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    • pp.1073-1079
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    • 1998
  • The potential energy surface (PES) of the non-identical SN2 reactions, F- + CH3Cl → FCH3 + Cl and (H2O)F + CH3Cl → FCH3 + Cl-(H2O), were investigated with ab initio MO calculations. The ab initio minimum energy reaction path (MERP) of the F- + CH3Cl → FCH3 + Cl- was obtained and it was expressed with an intermediate variable t. The ab initio PES was obtained near around t. Analytical potential energy function (PEF) was determined as a function of the t in order to reproduce the ab initio PES. Based on Morse-type potential energy function, a Varying Repulsive Cores Model (VRCM) was proposed for the description of the bond forming and the bond breaking which occur simultaneously during the SN2 reaction. The MERP calculated with the PEF is well agreed with the ab initio MERP and PEF could reproduce the ab initio PES well. The potential parameters for the interactions between the gas phase molecules in the reactions and water were also obtained. ST2 type model was used for the water.