• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.4
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• pp.128-135
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• 1998

In the high speed range for salient type synchronous reluctance motor, the effect of iron loss can not be negligible. In this paper, under he assumption that stator iron loss is generated from the equivalent eddy current in the stator, we derive the voltage equations including iron loss from the model that is added the equivalent iron loss in the equivalent inductance in series. The variation of iron loss is dependent on the increase of the operating frequency change for he worse a performance of the vector control system. As there is cross coupling between the d and q axes, it is hard to apply the vector control to the proposed model. Hence, we propose a decoupling current controller for including the effects of iron loss, And we show that the proposed vector control scheme achieves the desired performances through simulation results.

• Journal of Ocean Engineering and Technology
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• v.26 no.4
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• pp.57-63
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• 2012

In this paper, a Bayesian classifier based on PCA (principle component analysis) is proposed to classify underwater transient signals using $16^{th}$ order LPC (linear predictive coding) coefficients as feature vector. The proposed classifier is composed of two steps. The mechanical signals were separated from biological signals in the first step, and then each type of the mechanical signal was recognized in the second step. Three biological transient signals and two mechanical signals were used to conduct experiments. The classification ratios for the feature vectors of biological signals and mechanical signals were 94.75% and 97.23%, respectively, when all 16 order LPC vector were used. In order to determine the effect of underwater noise on the classification performance, underwater ambient noise was added to the test signals and the classification ratio according to SNR (signal-to-noise ratio) was compared by changing dimension of feature vector using PCA. The classification ratios of the biological and mechanical signals under ocean ambient noise at 10dB SNR, were 0.51% and 100% respectively. However, the ratios were changed to 53.07% and 83.14% when the dimension of feature vector was converted to three by applying PCA. For correct, classification, it is required SNR over 10 dB for three dimension feature vector and over 30dB SNR for seven dimension feature vector under ocean ambient noise environment.

• The KIPS Transactions:PartD
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• v.19D no.2
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• pp.151-160
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• 2012

Most of the distributed high-dimensional indexing structures provide a reasonable search performance especially when the dataset is uniformly distributed. However, in case when the dataset is clustered or skewed, the search performances gradually degrade as compared with the uniformly distributed dataset. We propose a method of improving the k-nearest neighbor search performance for the distributed vector approximation-tree based on the strongly clustered or skewed dataset. The basic idea is to compute volumes of the leaf nodes on the top-tree of a distributed vector approximation-tree and to assign different number of bits to them in order to assure an identification performance of vector approximation. In other words, it can be done by assigning more bits to the high-density clusters. We conducted experiments to compare the search performance with the distributed hybrid spill-tree and distributed vector approximation-tree by using the synthetic and real data sets. The experimental results show that our proposed scheme provides consistent results with significant performance improvements of the distributed vector approximation-tree for strongly clustered or skewed datasets.

• The KIPS Transactions:PartD
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• v.14D no.7
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• pp.801-808
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• 2007

Video coding standards such as MPEG-2, MPEG-4, H.263, and H.264 transmit a compressed video data using wired/wireless communication line with limited bandwidth. Because highly compressed bit-streams is likely to fragile to error from channel noise, video is damaged by error. There have been many research works on error concealment techniques, which recover transmission errors at decoder side [1, 2]. We designed an error concealment technique for lost motion vectors of H.264 video coding. In this paper, we propose a Kalman filter based motion vector recovery scheme, and experimented with standard video sequences. The experimental results show that our scheme restores original motion vector with more precision of 0.91 - 1.12 on average over conventional H.264 decoding with no error recovery.

• Bulletin of the Korean Mathematical Society
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• v.48 no.2
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• pp.377-386
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• 2011

For a smooth algebraic curve C of genus g $\geq$ 4, let $SU_C$(r, d) be the moduli space of semistable bundles of rank r $\geq$ 2 over C with fixed determinant of degree d. When (r,d) = 1, it is known that $SU_C$(r, d) is a smooth Fano variety of Picard number 1, whose rational curves passing through a general point have degree $\geq$ r with respect to the ampl generator of Pic($SU_C$(r, d)). In this paper, we study the locus swept out by the rational curves on $SU_C$(r, d) of degree < r. As a by-product, we present another proof of Torelli theorem on $SU_C$(r, d).

• Journal of Broadcast Engineering
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• v.2 no.1
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• pp.36-44
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• 1997

We propose 3D perspective display using elevation matrix data with 2D information overlay. This algorithm is based on ID scan-line method and we used color index of the newly developed raster map, VRRG(Vector Restored Raster Graphics). The proposed method allows the fast generation of perspective view of 3D data with 2D overlay and the fast selective display of the features of 2D overlay.

• Parasites, Hosts and Diseases
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• v.55 no.3
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• pp.319-325
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• 2017

We described 4 human infection cases of zoonotic fish-tapeworm, Diphyllobothrium nihonkaiense, identified with morphological and molecular characters and briefly reviewed Chinese cases in consideration of it as an emerging parasitic disease in China. The scolex and mature and gravid proglottids of some cases were seen, a rosette-shaped uterus was observed in the middle of the mature and gravid proglottids, and the diphyllobothriid eggs were yellowish-brown in color and displayed a small knob or abopercular protuberance on the opposite end of a lid-like opening. The average size of the eggs was recorded as $62-67{\times}42-45{\mu}m$. The parasitic materials gathered from 4 human cases were morphologically identified as belonging to the genera Diphyllobothrium and Adenocephalus. The phylogenetic analysis based on the nucleotide sequences of cytochrome c oxidase subunit 1 gene of the etiologic agents confirmed that the 4 cases were D. nihonkaiense infection. The finding of 4 additional D. nihonkaiense cases suggests that D. nihonkaiense might be a major causative species of human diphyllobothriasis in China. A combined morphological and molecular analysis is the main method to confirm D. nihonkaiense infection.

• Journal of Broadcast Engineering
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• v.15 no.3
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• pp.426-433
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• 2010

The H.264/AVC video coding standard performs inter prediction using variable block sizes to improve coding efficiency. Since we predict not only the motion of homogeneous regions but also the motion of non-homogeneous regions accurately using variable block sizes, we can reduce residual information effectively. However, each motion vector should be transmitted to the decoder. In low bit rate environments, motion vector information takes approximately 40% of the total bitstream. Thus, motion vector competition was proposed to reduce the amount of motion vector information. Since the size of the motion vector difference is reduced by motion vector competition, it requires only a small number of bits for motion vector information. However, we need to send the corresponding index of the best motion vector predictor for decoding. In this paper, we propose a new codeword table based on the phased-in code to encode the index of motion vector predictor efficiently. Experimental results show that the proposed algorithm reduces the average bit rate by 7.24% for similar PSNR values, and it improves the average image quality by 0.36dB at similar bit rates.

• Journal of Korea Multimedia Society
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• v.15 no.6
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• pp.731-736
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• 2012

Latest digital cinema is getting more interest on recent days. The combination of visually immersive 3D movie with chair movements and other physical effects has added more enjoyment. The movement of the chair is controlled manually in these digital cinemas. By the analysis of the digital cinema's video sequences, movement of the chair can be controlled automatically. In the proposed method first of all the motion of focused object and the background is identified and then the motion vector information is extracted by using the 9-search range. The motion vector is determined only for the movement of background while the object is stationary. The extracted Motion information from the digital cinemas is used for the movement control of the chair. The experimental results show that the proposed method outperforms the existing methods in terms of accuracy.

• Biomedical Science Letters
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• v.12 no.3
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• pp.139-143
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• 2006

Jopock (Jpk) has previously been ascertained that induces both bacterial and mammalian cell death. The Escherichia coli cells expressing Glutathion S-transferase (GST) fused Jpk showed elongated phenotype and inhibited cell growth which led eventual cell death. In an attempt to search the genetic suppressor of the lethal protein Jpk in bacterial cells, we constructed a unidirectional protein expression vector inserting tac promoter next to the C-terminus Jpk in pGEX-Jpk. The function of additional tac promoter was confirmed by substituting lac promoter in Plac-TOPO plasmid. The cells harboring plac- TOPO, which regulates $lacZ{\alpha}$ gene expression under lac promoter, formed blue colonies in 5-bromo-4-3 $indolyo-{\beta}-D-galactoside$ (X-gal) plate. When lac promoter was changed to tac promoter, same results were observed. Since the addition of tac promoter did not affect the toxic effect of Jpk, the pGEX-Jpk-ptac could be a useful vector for the screening of suppressor(s) for Jpk, in which GST-Jpk and a putative Jpk-suppressing protein are coexpressing from two unidirectional tac promoters, which response to the same inducer, $isopropyl-{\beta}-D-thiogalactopyranoside (IPTG)$.