• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.4B
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• pp.725-733
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• 2000

In this paper, we propose a modified boundary block merging technique for the texture coding of MPEG-4. We propose an ORP(Optimized Region Partitioning) method that partition the VOP-based reference position to minimize the number of coding blocks. The merging possibility is improved by adding +90。and -90。 Rotation merging. We propose a MRM(Multiple Rotation Merging) method which applies the rotation merging in the order of 180。, +90。and -90。. If a pair of boundary blocks has low correlation, existing BBM's padding technique is not efficient. Our padding after merging method gives better result even if it has low correlation. The proposed method showed 5 ~8(%) coding bit reduction at the same PSNR values compared to BBM method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11C
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• pp.712-719
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• 2011

In this paper, we analyzed the performance of soft decision e-BCH codes which presented in DVB-RCS NG system. However, the performance of soft-decision decoding for e-BCH is not much improved as to increase the iterations. Therefore this paper proposed rate-compatible TPC which makes various coding rates by zero padding the row and/or column to adapt next generation (NG) DVB-RCS system. And so we proposed new model of extended BCH code and researches how to develop performance of extended BCH code.

• Journal of Internet Computing and Services
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• v.3 no.5
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• pp.9-17
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• 2002

CSIX-L1 is the Common Switch Interface that defines a physical interface for transferring information between a traffic manager (Network Processor) and a switching fabric in ATM, IP, MPLS, Ethernet and data communication areas. In Tx, data to be transmitted is generated in Cframe which is the base information unit and in Rx, original data is extracted from the received Cframe. CSIX-L1 suppots the 32, 64, 96, and 123-bit interface and generates a variable length CFrame and Idle Cframe. Also CSIX-L1 appends Padding byte and supports 16-bit Vertical parity, CSIX-L1 is designed using Xilinx 4,1i. After functional and timing simulations are completed. CSIX-L1 module is downloaded in Xilinx FPGA XCV1000EHQ240C and verified. The synthesized CSIX module operates at 27MHz.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.7
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• pp.747-749
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• 2016

We consider a time-division multiple-access relay channel (MARC), in which two source nodes (SNs) transmit data with different data rate to a destination node (DN) with the help of a relay node (RN) using network coding (NC). However, due to its asymmetric data rate, the RN cannot combine the received bits by XOR NC. In this paper, we compare with the problem of asymmetric data rates by using zero padding and hierarchical 16QAM.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1654-1668
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• 1992

The acoustic field resulted by the radiation of sound from vibrating structure is predicted based on the sound pressure measurements. The sound pressures are measured at discreate point on the measurement plane ; Hologram. Based on these discreate measurements, the sound field away from the acoustic source is constructed based on the discreate form of Kirchhoff-Helmohltz integral equations The velocities, intensities, and pressures of arbitrary plane of interest in space are predicted and visualized The effects on the sound field reconstruction ; finite aperture effect, effect of finite sampling interval in space studied in terms of wraparound error and spatial aliasing. Numerical simulations and experimental verifications are performed to see these effects. To reduce the wraparound error, zero padding technique in space is used and the usefulness of the method is demonstrated by various examples.

• Journal of the Korean Society of Clothing and Textiles
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• v.5 no.2
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• pp.35-40
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• 1981

This study aims at finding appropriate adhesive conditions with special regard the material of 'fusible padding cloth inter ling' was frequently used for leather. As for leather material, pig suede, sheep suede were selected and drum dyed, cow split, napa have also been used. Mixed spinning non-woven fabric (polyester $50\%$, nylon $50\%$) were used as for padding cloth. Experimental appearance has been observed under the following adhesive conditions: Temperature of press were devided four levers; $120^{\circ}C$, $130^{\circ}C$, $140^{\circ}C$, $150^{\circ}C$, respectively. Adhesive time has been limited 5, 10, 15 second each. And the pressure has been conditioned as $0.2kg/cm^2$ continuously. After all this experiment, it was discovered that the material which had long contact with low temperature conditions has similar adhesive power to material that has short contact with high temperature conditions. There is a great difference according to the leather's dying process, the finishing method of the cloth, and the part of leather surface. The best condition for suede are $140^{\circ}C$, $150^{\circ}C$, at 10 seconds. and for D/D, NAPA, $130^{\circ}C$, at 10 seconds. Although the conditions of $150^{\circ}C$, at 15 seconds was possible for split, the process time can be shortened according to the increase of temperature.

• Journal of the Korean Home Economics Association
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• v.41 no.6
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• pp.157-166
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• 2003

The purpose of this study was to provide information on how to improve the current design of infant coveralls through analysis of the design preferences of Korean consumer. In order to compile the information about preferences with the detail design of infant coveralls, a questionnaire was administered to mothers of 241 infants (aged under 36 months) living in Seoul, and analyzed using the SPSS WIN.10.0 program. The results of this study were as follows : 1) Results of buying conditions and design preference of infant coverall : To the question asking what kind of materials they preferred according to the season as material for infant coverall, the respondents preferred cotton hit as the materials for summer, but padding material for winter. The most favored design type were a flat collar, regular bodice type without cutting line, a raglan sleeves, snap front fastener, elastic band cuffs. 2) There is significant difference in preferred material and design among the month of age groups. 3) Analysis of the differences in preferred material and detail design according to gender In preferred material, it seemed as if girl baby group prefer cotton knit material, while boy baby group prefer padding material. There is definite difference in preferred neckline type, girl baby group prefer flat collar, while boy baby group prefer stand collar.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.3
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• pp.172-179
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• 2013

In this paper, we consider network-coded bi-directional relaying (NCBR) schemes over an asymmetric channel, in which bi-directional links have the different channel quality, as well as the asymmetric traffic load. In order to deal with asymmetric nature, two different types of NCBR schemes are considered: network coding after padding (NaP) and network coding after fragmentation (NaF). Even if NaP has been known as only a useful means of dealing with the asymmetry in traffic load up to now, our analysis shows that its gain can be significantly lost by the asymmetry in channel quality, under the given bit error performance constraint. Furthermore, it is shown that NaF always outperforms NaP, as well as traditional bi-directional relaying scheme.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.2
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• pp.222-228
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• 2016

We provide an aggressive spatial reuse scheme exploiting the space sensed busy when neighboring 802.11 stations radiate radio wave in omni-directions. For this purpose, we develop four strategies, i.e., disruptive RTS, busy random backoff, zero padding, and unavailable pair management. The simulation results show that the proposed scheme can improve the aggregate network throughput from 14% to 50% while the station adopting the proposed scheme coexists with the legacy stations.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.1 s.6
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• pp.57-62
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• 2005

In this paper, we propose a channel estimation method by impulse signal train in OFDM. In order to estimate the channel response, 4 impulse signals are generated and transmitted during one OFDM (Orthogonal Frequency Division Multiplexing) symbol. The intervals between the impulse signals are all equal in time domain. At the receiver, the impulse response signals are summed and averaged. And then, the averaged impulse response signal is zero padded and fast Fourier transformed to obtain the channel estimation. The BER performance of the proposed method is compared with those of conventional estimation method using the long training sequence in fast fading environments. The simulation results show that the proposed method improves by 3 dB in terms of Eb/No, compared with the conventional method.