• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.5
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• pp.29-34
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• 2002

This study presents the process of the continuous-time system identification for unknown nonlinear systems. The Radial Basis Function(RBF) error filtering identification model is introduced at first. This identification scheme includes RBF network to approximate unknown function of nonlinear system which is structured by affine form. The neural network is trained by the adaptive law based on Lyapunov synthesis method. The identification scheme is applied to engine and the performance of RBF error filtering Identification model is verified by the simulation with a three-state engine model. The simulation results have revealed that the values of the estimated function show favorable agreement with the real values of the engine model. The introduced identification scheme can be effectively applied to model-based nonlinear control.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.6
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• pp.62-70
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• 2008

An adaptive fuzzy backstepping controller is proposed for the motion control for a single-link flexible-joint robot in the presence of parametric uncertainties. Fuzzy logic system is used to approximate the uncertainties of functions and a backstepping technique is employed to deal with the mismatched problem. A compensation controller is also employed to estimates the bound of approximation error so that the shattering effect of the control effort can be reduced. Thus the asymptotic stability of the closed loop control system can be obtained based on a Lyapunov synthesis approach. Numerical simulation results for a single-link flexible-joint robot are included to show the effectiveness of proposed controller.

• Bulletin of the Society of Naval Architects of Korea
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• v.9 no.1
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• pp.1-6
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• 1972

To contribute towards more accurate estimation of the virtual coefficient for the vertical vibration of the chine-type ship, experimentally obtained three-dimensional correction factors, J, of added mass of prismatic beams having cross section shape of hypotrocoid characters, slightly concaved Lewis form and elliptic form are investigated in connection with the applicability of an approximate analytical calculation method compared to that proposed by T. Kumai[6] for the Lewis form cylinders, and synthetically in compared with the experimental works on various cross section shapes of the other type by L.C. Burril et al[8] and the analytical works on the ellipsoid of revolution by F.M. Lewis[1] and J.L. Taylor[2]. The experimental results show that the aforementioned analytical method gives, unlike that for the Lewis form cylinders, considerably larger J-values for the chine-type cylinders, and that the influence of the character of the cross section shape on J-values is not remarkable in practical sense. Finally, considering in synthesis the experimental results on prismatic beams, the Burril's works on palabolic plan form and elliptic plan form, and that the chine-type ship usually has a hull form of transom stern, it is fairly safe to say, at the present stage, that adoptation of the Taylor's J-values will not results in any large error in estimation of the virtual inertia coefficients of the chine-type ships.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.1
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• pp.183-200
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• 2020

This paper presents an efficient interactive framework for perspective scene completion and editing tasks, which are available largely in the real world but rarely studied in the field of image completion. Considering that it is quite hard to extract perspective information from a single image, this work starts from a friendly and portable interactive platform to obtain the basic perspective data. Then, in order to make this interface less sensitive, easier and more flexible, a perspective-rectification based correction mechanism is proposed to iteratively update the locations of the initial points selected by users. At last, a complanate mesh is generated by the geometry calculations from these corrected initial positions. This mesh must approximate the perspective direction and the structure topology as much as possible so that the filling process can be conducted under the constraint of the perspective effects of the original image. Our experiments show the results with good qualities and performances, and also demonstrate the validity of our approaches by various perspective scenes and images.

• International Journal of Aeronautical and Space Sciences
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• v.14 no.2
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• pp.172-182
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• 2013

This paper focuses on the modeling and intelligent control of the new Eight-Rotor MAV, which is used to solve the problem of the low coefficient proportion between lift and gravity for the Quadrotor MAV. The Eight-Rotor MAV is a nonlinear plant, so that it is difficult to obtain stable control, due to uncertainties. The purpose of this paper is to propose a robust, stable attitude control strategy for the Eight-Rotor MAV, to accommodate system uncertainties, variations, and external disturbances. First, an interval type-II fuzzy neural network is employed to approximate the nonlinearity function and uncertainty functions in the dynamic model of the Eight-Rotor MAV. Then, the parameters of the interval type-II fuzzy neural network and gain of sliding mode control can be tuned on-line by adaptive laws based on the Lyapunov synthesis approach, and the Lyapunov stability theorem has been used to testify the asymptotic stability of the closed-loop system. The validity of the proposed control method has been verified in the Eight-Rotor MAV through real-time experiments. The experimental results show that the performance of the interval type-II fuzzy neural network based adaptive sliding mode controller could guarantee the Eight-Rotor MAV control system good performances under uncertainties, variations, and external disturbances. This controller is significantly improved, compared with the conventional adaptive sliding mode controller, and the type-I fuzzy neural network based sliding mode controller.

• Fire Science and Engineering
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• v.14 no.3
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• pp.19-26
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• 2000

As a basic physical property of chemical substances, the flash point is of great importance as far as the prevention of chemical disasters is concerned. The measurement of flash point is not easy. and the number of c(Impounds for which systematic data have been collected pitifully small. Because, a need exists for some means of predicting the flash point of compound for which experimental data are unavailable, not only those which are currently in use or at the production stage, but also, those not compounds which are in the process of synthesis and design. The present research concerns the application of OCD (organic conception diagram) to the association between chemical structures and flash points, and an attempt made to discover a method of predicting the approximate flash point of a compound from its chemical structure alone.

• Bulletin of the Society of Naval Architects of Korea
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• v.25 no.1
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• pp.11-20
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• 1988

From the engineering point of view, a synthesis as well as an analysis technique is explored to search for the improved design of grillage which is common in ship structure. As an approximate analysis method for the grillage, an interaction reaction method is developed and compared with the finite element method. It is found that the discrepancy between these two methods is so negligible that the percent method could be used effectively for the grillage analysis. As an optimization technique, a feasible direction method could be used is combined with the intersection reaction method in order to design a minimum weight optimal grillage. The feasible direction method shows a good numerical performance although it requires more calculation times compared with the direct search method. Finally, the application of multiple objective optimization method to grillage is investigated in order to resolve conflicts existed between the multiple objectives which is a common characteristic of structure design problem. Goal programming method is extended to handle a nonlinear property of constraints and objective functions. It seems that the nonlinear goal programming could help not only to establish a relative importance of each objective, but also enable the designer to choose the best combination of design variables.

• Journal of Radiation Industry
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• v.8 no.1
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• pp.29-34
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• 2014

Nanogels are internally cross-linked particles of sub-micrometer size made of hydrophilic polymers and are considered a distinct type of macromolecules, compared with linear and branched polymers or macroscopic gels. In this study, we studied a method of radiation induced synthesis of nanogels, which allows us to obtain tailored intra-molecularly crosslinked macromolecules of independently chosen molecular weight and dimensions. Thus, we report the possibility of applying the prepared nanogels using poly(acrylic acid) through electron beam irradiation for potential application as biomaterials. The nanogels were characterized by scanning electron microscopy (SEM). In addition, the size and zeta-potential of nanogels were measured by a particle size analyzer (PSA). The nanogels were prepared at an approximate size of 180 nm at 100 kGy and were spherical in shapes. The size of the nanogels decreased with increasing irradiation doses, and the absolute value of zeta potential increased with increasing irradiation doses.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1326-1335
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• 2005

The main purpose of this study is to investigate the effects of dietary lysine deficiency on protein turnover of porcine muscles. There were 18 LYD three-breed-crossing postweanling barrows from six litters cannulated with gastric tubes through the esophagus at approximate 10 kg of body weight and allocated into three treatment groups. When their body weights reached over 12 kg, one group was sacrificed for determining the initial protein masses of m. masseter, m. longissimus dorsi, m. adductor and m. biceps femoris from the right body side. The others received a diet containing 100% or 61.4% (calculated values) of the lysine requirement (NRC, 1998) multiplied by 1.103 for a period of 17 days. Daily feed provision was computed for each pig according to body weight at the same day. All pigs were infused a flooding dose of $^2$H$_5$-phenylalanine to determine the fractional protein synthesis rates (FSR) of the aforementioned muscles in the end. Their four muscles from the right body side were also dissected for measuring the fractional rates of protein accretion (FAR). As for protein degradation, fractional rates (FDR) were calculated by differences between synthesis and accretion. Results showed that the lysine deficiency resulted in, significantly (p<0.05), lighter body weights, smaller muscles and a slower growth rate. The protein mass, accreted by the muscles, of the deficient group was only 54% averaged of the pigs fed adequately (p<0.05). The FAR of these muscles in the deficient group was significantly lower (p<0.05) and only achieved 61.1% averaged of the control; there was no significant difference (p>0.05), nevertheless, in the amino-acid composition of muscles between two groups. The lysine deficiency reduced significantly (p<0.05) the FSR of m. longissimus dorsi but did not influence its FDR. The m. biceps femoris also presented an inhibited FSR while its FDR reduced only exhibited a very high tendency (p = 0.055) compared to the adequately-fed pigs. As for the m. masseter and m. adductor, both of the FSR and FDR were depressed significantly (p<0.05) by the lysine deficiency, and changes in the FSR were severer than those in the FDR, so that their FAR were significantly slower (p<0.05) in comparison with the control group. The lysine deficiency also inhibited the RNA translation activity of the muscles while the effects on RNA capacity were not significant (p>0.05). In conclusion, the FAR of muscle protein was changed by the current lysine deficiency through the alterations in the FSR and/or FDR.

• Journal of Internet Computing and Services
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• v.18 no.5
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• pp.17-22
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• 2017

In a MPC coding using excitation source of voiced and unvoiced, it would be a distortion of speech waveform. This is caused by normalization of synthesis speech waveform of voiced in the process of restoration the multi-pulses of representation section. This paper present PCFBD-MPC( Position Compensation Frequency Band Division-Multi Pulse Coding ) used V/UV/S( Voiced / Unvoiced / Silence ) switching, position compensation in a multi-pulses each pitch interval and Unvoiced approximate-synthesis by using specific frequency in order to reduce distortion of synthesis waveform. Also, I was implemented that the PCFBD-MPC( Position Compensation Frequency Band Division-Multi Pulse Coding ) system and evaluate the SNRseg of PCFBD-MPC in coding condition of 8kbps. As a result, SNRseg of PCFBD-MPC was 13.4dB for female voice and 13.8dB for male voice respectively. In the future, I will study the evaluation of the sound quality of 8kbps speech coding method that simultaneously compensation the amplitude and position of multi-pulse source. These methods are expected to be applied to a method of speech coding using sound source in a low bit rate such as a cellular phone or a smart phone.