• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1834-1846
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• 2020

The SMART (System-integrated Modular Advanced ReacTor) is an integral-type small modular reactor developed by KAERI (Korea Atomic Energy Research Institute). This paper discusses the development of a dynamic equivalent model of the SMART control rod drive mechanism that can be efficiently utilized for complicated analysis during the design of the SMART. A semi-empirical approach is used to develop the equivalent model; that is, the equivalent model is defined analytically and verified empirically. Two types of tests, dynamic characteristics tests and seismic loading tests, are conducted for the development and verification of the dynamic equivalent model, respectively. Acceleration response spectra from the seismic analysis based on the developed equivalent model show good agreement with those from the seismic loading tests.

• Journal of Mechanical Science and Technology
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• v.16 no.1
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• pp.13-23
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• 2002

This paper presents inverse kinematic and dynamic analyses of HexaSlide type six degree-of-freedom parallel manipulators. The HexaSlide type parallel manipulators (HSM) can be characterized as an architecture with constant link lengths that are attached to moving sliders on the ground and to a mobile platform. In the inverse kinematic analyses, the slider and link motion (position, velocity, and acceleration) is computed given the desired mobile platform motion. Based on the inverse kinematic analysis, in order to compute the required actuator forces given the desired platform motion, inverse dynamic equations of motion of a parallel manipulator is derived by the Newton-Euler approach. In this derivation, the joint friction as well as all link inertia are included. Relative importance of the link inertia and joint frictions on the computed torque is investigated by computer simulations. It is expected that the inverse kinematic and dynamic equations can be used in the computed torque control and model-based adaptive control strategies.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.856-859
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• 2006

The effects of moisture content on non-fracture dynamic properties and fracture gel quality of Pacific whiting surimi were investigated to determine their relationships. Surimi samples were tested at various moisture contents (75, 78, and 81 %). Torsion test showed that shear stress decreased rapidly and strain values decreased gradually as moisture concentration increased. Dynamic storage modulus (G') also decreased as moisture content increased. A strong positive correlation ($R^2=0.90$ to 0.99) was found between the G' measured at temperatures between 10 and $45^{\circ}C$ and fracture stress values. The results indicate that dynamic rheological measurements could be used as a tool for early gel quality assessment.

• Advances in Computational Design
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• v.5 no.3
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• pp.233-260
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• 2020

The main purpose to introduce model based controller in proposed control technique is to provide better and fast learning of the floating dynamics by means of fuzzy logic controller and also cancelling effect of nonlinear terms of the system. An iterative adaptive dynamic programming algorithm is proposed to deal with the optimal trajectory-tracking control problems for autonomous underwater vehicle (AUV). The optimal tracking control problem is converted into an optimal regulation problem by system transformation. Then the optimal regulation problem is solved by the policy iteration adaptive dynamic programming algorithm. Finally, simulation example is given to show the performance of the iterative adaptive dynamic programming algorithm.

• Journal of the Korean Wood Science and Technology
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• v.39 no.5
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• pp.398-405
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• 2011

Nondestructive evaluation (NDE) technique method using a resonance frequency mode was carried out for woodceramics made by different phenol resin impregnation ratios (40, 50, 60, 70%) for Broussonetia Kazinoki Sieb. Dynamic modulus of elasticity increased with increasing resin impregnation ratios. There was a close relationship between dynamic modulus of elasticity and static bending modulus of elasticity and between dynamic modulus of elasticity and MOR and between static bending modulus of elasticity and MOR. Therefore, the dynamic modulus of elasticity using resonance frequency mode is useful as a nondestructive evaluation method for predicting the MOR of woodceramics made by different impregnation ratios.

• The Journal of Korea Robotics Society
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• v.11 no.3
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• pp.140-145
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• 2016

In this paper, we fabricate arrayed-type flexible capacitive touch sensor using liquid metal (LM) droplets (4 mm spatial resolution). Poly-4-vinylphenol (PVP) layer is used as a dielectric layer on the electrode patterned Polyethylene naphthalate (PEN) film. Bonding tests between hydroxyl group (-OH) on the PVP film and polydimethylsiloxane (PDMS) are conducted in a various $O_2$ plasma treatment conditions. Through the tests, we can confirm that non-$O_2$ plasma treated PVP layer and $O_2$ plasma treated PDMS can make a chemical bond. To measure dynamic range of the device, one-cell experiments are conducted and we confirmed that the fabricated device has a large dynamic range (~60 pF).

• Journal of Electrical Engineering and Technology
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• v.1 no.4
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• pp.482-489
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• 2006

This paper presents the generalized dynamic modeling of self-excited induction generator (SEIG) using state-space approach. The proposed dynamic model consists of induction generator; self-excitation capacitance and load model are expressed in stationary d-q reference frame with the actual saturation curve of the machine. An artificial neural network model is implemented to estimate the machine magnetizing inductance based on the knowledge of magnetizing current. The dynamic performance of SEIG is investigated under no load, with the load, perturbation of load, short circuit at stator terminals, and variation of prime mover speed, variation of capacitance value by considering the effect of main and cross-flux saturation. During voltage buildup the variation in magnetizing inductance is taken into consideration. The performance of SEIG system under various conditions as mentioned above is simulated using MATLAB/SIMULINK and the simulation results demonstrates the feasibility of the proposed system.

• ETRI Journal
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• v.43 no.6
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• pp.1058-1080
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• 2021

Crime is not a completely random event but rather shows a pattern in space and time. Capturing the dynamic nature of crime patterns is a challenging task. Crime prediction models that rely only on neighborhood influence and demographic features might not be able to capture the dynamics of crime patterns, as demographic data collection does not occur frequently and is static. This work proposes a novel approach for crime count and hotspot prediction to capture the dynamic nature of crime patterns using taxi data along with historical crime and demographic data. The proposed approach predicts crime events in spatial units and classifies each of them into a hotspot category based on the number of crime events. Four models are proposed, which consider different covariates to select a set of independent variables. The experimental results show that the proposed combined subset model (CSM), in which static and dynamic aspects of crime are combined by employing the taxi dataset, is more accurate than the other models presented in this study.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.137-140
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• 2021

High dynamic range (HDR) technology has been drawing attention in the field of imaging and consumer entertainment. As tools for capturing and creating HDR contents, encoding, and transmission evolve to support HDR formats, various display capabilities are being developed and increased. Hence, there is need for remapping native HDR imagery for display on lower quality legacy standard dynamic range (SDR) displays. This operation is referred to as tone mapping. In this paper, we present a sectional tone mapping method by Lenzen, and expand upon a tone mapping approach to improve temporal stability while maintaining picture quality. Compared to the existing block-based sectional tone mapping, our method uses the edge awareness-based tone mapping. We estimate the performance of the objective metric on temporal flickering. The experimental result shows that the algorithm maintains a smoother relationship between the output luminance values, and this reveals success in reducing halos and improving temporal stability with adopted edge aware filtering.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.317-320
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• 2005

In this paper, dynamic behaviour of short circuit occurring in Pulse Gas Metal Arc Welding (GMAW-P) is investigated Welding experiments with different values of pulsing parameters, high speed camera pictures and welding signals such as current and voltage were acquired to identify short circuit conditions in GMAW-P.