• 한국시뮬레이션학회논문지
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• 제1권1호
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• pp.64-76
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• 1992

The DEVS(discrete event system specificaition) formalism specifies a discrete event system in a hierarchical, modular form. DEVSIM++ is a C++based general purpose DEVS abstract simulator which can simulate systems modeled by the DEVS formalism in a sequential environment. This paper describes P-DEVSIM++which is a parallel version of DEVSIM++ . In P-DEVSIM++, the external and internal event of DEVS models can by processed in parallel. For such processing, we propose a parallel, distributed optimistic simulation algorithm based on the Time Warp approach. However, the proposed algorithm localizes the rollback of a model within itself, not possible in the standard Time Warp approach. An advantage of such localization is that the simulation time may be reduced. To evaluate its performance, we simulate a single bus multiprocessor architecture system with an external common memory. Simulation result shows that significant speedup is made possible with our algorithm in a parallel environment.

• ETRI Journal
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• 제43권2호
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• pp.197-208
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• 2021

Single-carrier frequency division multiple access (SC-FDMA) is currently being used in long-term evolution uplink communications owing to its low peak-to-average power ratio (PAPR). This study proposes a new transceiver design for an SC-FDMA system based on Walsh-Hadamard transform (WHT). The proposed WHT-based SC-FDMA system has low-PAPR and better bit-error rate (BER) performance compared with the conventional SC-FDMA system. The WHT-based SC-FDMA transmitter has the same complexity as that of discrete Fourier transform (DFT)-based transmitter, while the receiver's complexity is higher than that of the DFT-based receiver. The exponential companding technique is used to reduce its PAPR without degrading its BER. Moreover, the performances of different ordered WHT systems have been studied in additive white Gaussian noise and multipath fading environments. The proposed system has been verified experimentally by considering a real-time channel with the help of wireless open-access research platform hardware. The supremacy of the proposed transceiver is demonstrated based on simulated and experimental results.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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• pp.96-97
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• 2009

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 춘계학술발표대회 논문집
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• pp.258.1-261
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• 1999

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 학술발표회 논문집(Proceedings of the Korean Textile Conference) 상
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• pp.243-246
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• 2001

• 복식
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• 제59권6호
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• pp.29-40
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• 2009

On April 28th of 2006, a set of Buddha's reliquary was excavated from the pagoda in n Nacsan Temple. According to the record, the relics were put in the pagoda in the 18th year of King SookJong in the Chosun Dynasty (1692). The present paper examines ten pieces of wrapping clothes covering reliquary found in the pagoda. They are especially precious data in the history of textiles because they were blocked off from outside and was preserved in good condition with vivid colors still remaining after more than 300 years. Of the ten pieces of wrapping cloth, five were double-layered and the other five were single-layered. They include 15 pieces of silk fabric but, excluding repeated use of the same silk fabric, the total of 11 pieces of silk fabric were examined. All 11 kinds of silk fabric were patterned, 9 of which were Satin and the other 2 were Twill. Of the 9 Satin pieces, 8 pieces were 5-end satin which had the ground of 5-end warp satin with the figure of 5-end weft satin. The remaining 1 Satin piece were more splendid with prominent figures by using warp and weft of different colors. The 2 Twill pieces used twill weave-the ground was 3-end warp twill and the figures were 5-end weft twill. Both of the Twill pieces were weaved with character patterns, partly using wrapped gold thread as supplementary weft. The patterns of 11 pieces of silk fabric include flower, dragon/phoenix, cloud, and geometric patterns. Five were flower patterns, three were dragon/phoenix patterns, two were geometric pattern, and one was cloud pattern. In addition, various treasure patterns, character patterns were utilized as supplementary patterns. The flower and phoenix patterns reflect characteristics of the textiles of the 17th century whereas check pattern and cloud pattern were very unique.

• 한국의류산업학회지
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• 제6권4호
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• pp.497-502
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• 2004

The mechanical properties of jean slacks to the type of cutting lines in knee region and the bending time, after doing bending 0 times, 500 times, and 1500 times, the effects of whether or not cutting line, the fabric direction of the cutting area, and the number of cutting lines were investigated for tensile, shearing, compression, and mixing value of mechanical properties. The results are as follows: EM to bending times were larger in order of weft

• 복식
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• 제57권1호
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• pp.93-104
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• 2007

This study is considered about the fabrics culture of Baekje Period by analyzing the fabrics pieces at a inner part of the It-bronze shoes found at the tomb of King Mu-ryeong in 1971 AD. The analysis methods of the fabrics pieces are a photographing of fabrics pieces surface by VMS, Digital camera(Nikon Coolpix 995) and the analysis of samples by SEM, XRD and FT-IR. It is assumed this fabrics pieces are the inner shoes, which consisted of compound woven silk at outward, some of tabby and a hemp at inward and the braids for decoration, of the gilt-bronze shoes. The features are as follows. 1. All of compound woven silk are the warp-faced compound tabby of plain fabrics and the density is various from high to low one. Compound woven silk which is attached the gilt-bronze shoes of the tomb of King Mu-ryeong weaves in high density by a thick thread. The fibers material of compound woven silk prove to be a silk by the analysis of wrap samples by SEM, XRD and FT-IR. 2. Tabby are excavated under the condition which attached on reverse side of compound woven silk. Those ran classify two types. First, the fine weaving by high density of wrap and weft. Second, the loose warp weaving with one warp and some of weft. 3. Hemp is almost ramie by SEM analysis and the density is different. Ramie which supposed to be attached Guem has the very low density. In addition to, Ramie pieces, excavated in condition and weaved finely, proved the conspicuous weaving skill in Baekje period. 4. Various kinds of braid are found and these ones classifies by fiber material and entwining way. Two types out of these are the one of silk thread, decorates the upper, middle parts of compound woven silk shoes and the other of hemp thread, decorates the lower parts.

• 한국의류산업학회지
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• 제17권3호
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• pp.462-475
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• 2015

This paper investigated the characteristics of the physical properties of woven fabrics according to the yarn structure and fibre property. It was found that wicking property of woven fabrics made of sheath/core hybrid yarn were better than those of siro spun and siro-fil hybrid yarns, which was caused by platform for transport of moisture vapor by filaments on the core part of sheath core hybrid yarns. In drying property, the fabric specimen woven by PP/Tencel sheath core hybrid yarns as a warp and Coolmax/Tencel spun yarn as a weft showed quick drying property, which was caused by the sheath core hybrid yarn structure as drainage of water moisture and coolmax fibre characteristics as quick dry material. Concerning to breathability and thermal conductivity as heat transport phenomena, it was observed that breathability of fabrics woven with hybrid yarns such as sheath core and siro-fil in the warp and hi-multi filaments in the weft showed the lowest water vapor resistance, which was explained as due to for air gap in the fibres of the spun yarns to restrict the wet heat transport from perspiration vapor. Thermal conductivities of the fabrics woven with PET/Tencel siro-fil yarns in the weft and hybrid yarns such as sheath core and siro-fil in the warp revealed the highest values, which was observed as due to higher thermal conductivity of PET than PP and more contact point between fibres in the siro-fil and sheath core hybrid yarns.

• 전기전자학회논문지
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• 제19권3호
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• pp.455-459
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• 2015

본 논문은 그래픽 처리 뿐 만 아니라 범용 연산의 가속화를 지원하기 위한 SIMT 구조 GP-GPU의 Dispatch Unit과 Operand Selection Unit을 제안한다. Warp Scheduler로부터 발행된 명령어에서 사용되는 Operand의 모든 정보를 Decoding 하면 불필요한 Operand Load가 발생하여 레지스터 부하가 발생 한다. 이러한 문제점을 해결하기 위해 Pre-decoding방법을 사용하여 Operand의 정보만을 먼저 Decoding 하여 Operand Load를 줄이고, 레지스터의 부하를 줄일 수 있는 방법을 제안한다. 제안하는 Dispatch Unit에서 나온 Operand 정보들을 레지스터 뱅크 충돌을 방지하는 방법을 적용한 Operand Selection Unit에 전달해 전체적인 처리 성능을 향상 시켰다. Modelsim 10.0b를 이용하여 Warp Scheduler로부터 발행된 10,000개의 임의의 명령어를 처리하여 소요되는 총 Clock Cycle을 측정하였다. 본 논문에서 제안한 Pre-Decoding 기능을 탑재한 Dispatch Unit과 Operand Selection Unit을 적용하여 기존의 방법들 보다 각각 약 11%, 24%의 처리 효율이 증가한 것을 확인 할 수 있었다.