• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.7
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• pp.620-628
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• 2010

Using the responses of deck plate, a new bridge weigh-in-motion system has been introduced. The approach includes not only a systematic algorithm for the extraction of moment influence sequence but also a sensitivity-based system identification technique. The algorithm indentifies the influence sequence, the axle loads, and axle location of moving vehicles on a bridge, simultaneously. The accuracy and practicability of the algorithm have been examined experimentally for a folded deck plate on Yongjong Grand suspension bridge. It turns out that the two-dimensional effects of the behavior of deck plate should be considered for further accuracy improvement.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1541-1547
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• 2006

An efficient procedure to obtain the optimal stacking sequence and the minimum weight of stiffened laminated composite curved panels under several loading conditions and stiffener layouts has been developed based on the finite element method and the genetic algorithm that is powerful for the problem with integer variables. Often, designing composite laminates ends up with a stacking sequence optimization that may be formulated as an integer programming problem. This procedure is applied for a problem to find the stacking sequence having a maximum critical buckling load factor and the minimum weight. The object function in this case is the weight of a stiffened laminated composite shell. Three different types of stiffener layouts with different loading conditions are investigated to see how these parameters influence on the stacking sequence optimization of the panel and the stiffeners. It is noticed from the results that the optimal stacking sequence and lay-up angles vary depending on the types. of loading and stiffener spacing.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.154-155
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• 2012

The dynamic voltage restorer (DVR) is an effective protection device for wind turbine generator based on doubly-fed induction generator (DFIG) operated under the unbalanced voltage dip conditions. The compensating voltages of DVR depend on the voltage dips and on the influence of the zero sequence components. If the $Y_0/{\Delta}$ step-up transformers are used, there are no zero sequence components on the DFIG side. However, if the $Y_0/Y_0$ step-up transformers are used, the zero sequence components will appear during faults. The zero sequence components result in the high insulation costs and the asymmetric of the terminal voltages. This paper proposes a method for controlling zero sequence components in DVR to protect DFIG under unbalanced voltage dips. Simulation results are presented to verify the effectiveness of the proposed control method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4645-4664
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• 2019

It is significant to construct deterministic measurement matrices with easy hardware implementation, good sensing performance and good cryptographic property for practical compressed sensing (CS) applications. In this paper, a deterministic construction method of bipolar chaotic measurement matrices is presented based on binary sequence family (BSF) and Chebyshev chaotic sequence. The column vectors of these matrices are the sequences of BSF, where 1 is substituted with -1 and 0 is with 1. The proposed matrices, which exploit the pseudo-randomness of Chebyshev sequence, are sensitive to the initial state. The performance of proposed matrices is analyzed from the perspective of coherence. Theoretical analysis and simulation experiments show that the proposed matrices have limited influence on the recovery accuracy in different initial states and they outperform their Gaussian and Bernoulli counterparts in recovery accuracy. The proposed matrices can make the hardware implement easy by means of linear feedback shift register (LFSR) structures and numeric converter, which is conducive to practical CS.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.2
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• pp.155-161
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• 2014

Industrial Static Var Generator (SVG) is typically applied at or near the load center to mitigate voltage fluctuation, flicker, phase unbalance, non-sine distortion or other load-related disturbance. Special attention is paid to the influence of grid voltage quality on SVG current, the non-sine distortion and unbalance of grid voltage causes not only the AC current distortion and unbalance but also the DC voltage fluctuation. In order to let the inverter voltage contain the fundamental negative sequence and harmonic component corresponding to the grid voltage, a new dual-loop control scheme is proposed to suppress the influence in this paper. The harmonic and negative sequence voltage decomposition algorithm and DC voltage control are also introduced. All these analyses can guide the practical applications. The simulation results verify the feasibility and effectiveness of the present control strategy and analyses.

• Speech Sciences
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• v.15 no.3
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• pp.53-63
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• 2008

This paper examined the acoustic differences in English speech production between English native speakers and Korean learners. Korean speakers seem to produce errors by over-applying the Korean phonological rules(nasalization and lateralization) to English speech under the conditions comparable to those of Korean which contain nasal+lateral or lateral+nasal sequences. Being based on this prediction, the experimental data is grouped into three sets, [n]+[l] sequence, [l]+[n]sequence, and [m]+[l] sequence. The result shows that, Korean speakers usually nasalize or lateralize the target words or phrases in every three categories while English natives don't. In set A([n]+[l] sequence), both nasalization and lateralization were found in [n]+[l] sequence, the same circumstances where both nasalization and lateralization can be placed as in Korean. In the case of set B([l]+[n] sequence), only lateralization is observed. It is because the nasalization never occurs in the sequence of l-n in Korean. There is no lateralization in set C([m]+[l] sequence), because only nasalization occurs in the sequence of m-l in Korean. This results reconfirmed that the nasalization and lateralization rules in Korean deeply influence on the English production data. Korean speakers need to be taught not to over-apply Korean phonological rule to English production for accurate pronunciation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.611-614
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• 2005

It is well known that tire tread pattern has much influence on the tire pattern noise. The paper describes the method of pattern noise reduction by using the pitch sequence, both on the smooth asphalt roads and on the trenched concrete roads. The noise of tire is classified as either airborne or structure borne noise. Pattern noise through the airborne is considered as a major noise source at high speeds. As block impacting and air pumping by tread patterns are major noise source, tire pattern noise can be greatly influenced by optimal pitch sequence. The goal of this paper is to provide tire engineers with pitch sequence to reduce pattern noise effectively.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.4
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• pp.169-174
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• 2002

The magnitude and phase of the compensating voltage in Dynamic Voltage Restorer (DVR) system depend on the voltage sag in the phases affected by the fault and on the influence of the zero sequence components. If the delta connection of the transformer is used, the zero sequence components do not appear on the load side. But nowadays, Y connected transformers with grounded neutral, that is 3-phase 4-wire system, are usually used. Therefore the zero-sequence components are occurred during faults. The zero-sequence components result in the high insulation costs and the asymmetry of the phase and magnitude of the terminal voltages. In this paper 3 phase 4 wire distribution system and 3 phase 3 wire system are analyzed and characteristics of voltage sag are presented. And this paper proposes the method that can mitigate the zero-sequence under the unbalance faults causing voltage sage and phase angle iumps.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.723-727
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• 2005

Ghrelin is a novel growth-hormone-releasing acylated peptide, which has been purified and identified in rat stomach. In the present study, the full-length sequence of bovine ghrelin cDNA was cloned by RT-PCR. The bovine ghrelin cDNA sequence derived in the present study included a 348 bp open reading frame and a 137 bp 3'UTR. The putative amino acid sequence of bovine prepro-ghrelin consisted of 116 amino acids, which contained the 27-amino acid ghrelin. The sequence analysis of the bovine ghrelin gene revealed that an intron existed between Gln$^{13}$ and Arg$^{14}$ of ghrelin. This exon-intron boundary matched the GT-AG rule of the splicing mechanism. Compared with rats, which have two tandem CAG sequences in the 3'end of intron, bovine ghrelin genome has only one CAG sequence. Therefore, although rats can produce 28 amino acid-ghrelin and 27 amino acid-des-Gln$^{14}$-ghrelin by alternative splicing, ruminant species, including bovines, might be able to produce only one type of ghrelin peptide, des-Gln$^{14}$-ghrelin. The influence of aging on plasma ghrelin concentration was also examined. Plasma ghrelin concentration increased after birth to approximately 600 days of age, and then remained constant.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.144-147
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• 2005

The tire is considered as one of the Important noise sources having an influence on vehicle's performance. The Pattern noise of a tire is the transmission sound of airborne noise. On smooth asphalt road, Pattern noise is amplified with the velocity. In recent, the study on the reduction of Pattern noise is energetically processed. Pattern noise is strongly related with pitch sequence. To reduce the pattern noise, tire's designer has to randomize the sequence of pitch. The FFT is a traditional method to evaluate the level of the randomization of the pitch sequence, but gives no information on time-varying, instantaneous frequency. In the study, we found that Time-Frequency transform is a useful method to non-stationary signal such as tire noise.