• Fibers and Polymers
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• 제6권1호
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• pp.72-78
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• 2005

The impact of fiber friction, yarn twist, and splicing air pressure on mechanical and structural properties of spliced portion have been reported in the present paper. The mechanical properties include the tensile and bending related properties and, in the structural properties, the diameter and packing density of the splices are studied. A three variable three level facto­rial design approach proposed by Box and Behnken has been used to design the experiment. The results indicate that there is a strong correlation between retained spliced strength (RSS) and retained splice elongation (RSE) with all the experimental variables. It has been observed that RSS increases with the increase in splice air pressure and after certain level it drops, whereas it consistently increases with the increase in yarn twist. The RSE increases with the increase in both fiber friction and yarn twist. It has also been observed that the yarn twist and splicing air pressure have significant influence on splice diameter, percent increase in diameter and retained packing coefficient, but the fiber friction has negligible influence on these parame­ters. Yarn twist and splicing air pressure has a strong correlation with splice flexural rigidity, where as poor correlation with retained flexural rigidity.

• 대한의생명과학회지
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• 제24권2호
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• pp.76-86
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• 2018

Breast cancer is one of the most common cancers affecting women worldwide. Although the survival rate of breast cancer has increased, breast cancer still results in a high mortality rate. Breast cancer deaths are caused by metastasis that occurs in organ dysfunction. Recently, there have been many studies on circulating tumor cells (CTCs), which are related to breast cancer metastasis in the blood. Recent studies have demonstrated that some CTCs do not express epithelial markers. Therefore, in this study, total RNA was extracted from blood without separating out the CTCs, and the characteristics of the CTCs were analyzed by RT-qPCR. Cyclin D1 and twist-related protein 1 (TWIST1) are well-known markers for predicting the prognosis of patients with breast cancer. However, few studies have demonstrated the use of CCND1 and TWIST1 in blood as diagnostic and prognostic markers of breast cancer. In this study, patients with late-stage breast cancer had overexpressed CCND1 and TWIST1 than patients with different stages of breast cancer (P < 0.001 and P < 0.01, respectively). The relative expression level of CCND1 in survivors was higher than in patients who died (P = 0.06). The relative expression level of TWIST1 in survivors was lower than in patients who died (P = 0.08). Overall CCND1 and TWIST1 were not useful as markers for the diagnosis of breast cancer through blood. However, we showed the possibility of using CCND1 and TWIST1 as prognostic markers, and a large-scale study is needed to confirm the usefulness of these prognostic markers.

• Asian Pacific Journal of Cancer Prevention
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• 제15권8호
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• pp.3797-3800
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• 2014

Background: BMI1, TWIST1 and SNAI2/SLUG have been implicated in aggressive behavior of squamous cell carcinoma (SCC) and melanoma and BMI1 expression could identify subtypes of Merkel cell carcinoma (MCC). However, BMI1, TWIST1 and SNAI2 expression levels in basal cell carcinomas (BCCs) have not been elucidated. We hypothesized BCC could be a good model system to decipher mechanisms which inhibit processes that drive tumor metastasis. The aim of this study was to examine the mRNA expression level of BMI1, TWIST1, and SNAI2 in BCCs. Materials and Methods: Thirty-five fresh non-metastatic BCC tissue samples and seven fresh normal skin tissue samples were evaluated by real-time RT-PCR. Results: BMI1 and TWIST1 demonstrated marked down-regulation (p<0.00l, p=0.00l respectively), but SNAI2 showed no significant change (p=0.12). Conclusions: Previous literature has clearly demonstrated a positive association between BMI1 and TWIST1 expression and metastatic BCC, aggressive SCC and melanoma. Here, we demonstrated a negative association between BMI1 and TWIST1 mRNA expression level and BCC.

• 한국염색가공학회지
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• 제23권1호
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• pp.35-42
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• 2011

For high quality DTP products, it is important to optimize the parameters of media, pre- and after-treatment, ink, printer, etc. This study investigated the effect of types of fabrics(media) as a DTP parameters. Especially, the effects of media properties such as yarn twist and knitted fabric structure, on printability and color difference were examined. Two types of cotton yarn twist(830 and 1630 twist/meter) and five knitted structures of media were prepared with a single circular knitting machine. The K/S values of hard-twist samples were higher than those of normal-twist samples in every media structures. It is more effective to use the knitted fabrics of a hard-twist yarn to obtain dark color in the printing above input level value 60 where the printability improvement was most pronounced in case of plain structure. Among the five media structures a plain structure was the highest and that of corduroy was the lowest in terms of K/S values. Also ${\Delta}E$ values and lightness of the hard-twist yarn samples were smaller than that of normal-twist yarn samples when ${\Delta}E$ values were tested by using a standard of a normal twist yarn sample with a plain structure, which was increased in the case of corduroy structure.

• Journal of information and communication convergence engineering
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• 제15권2호
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• pp.97-103
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• 2017

Implementation of faster pairing calculation is the basis of efficient pairing-based cryptographic protocol implementation. Generally, pairing is a costly operation carried out over the extension field of degree $k{\geq}12$. But the twist property of the pairing friendly curve allows us to calculate pairing over the sub-field twisted curve, where the extension degree becomes k/d and twist degree d = 2, 3, 4, 6. The calculation cost is reduced substantially by twisting but it makes the discrete logarithm problem easier if the curve parameters are not carefully chosen. Therefore, this paper considers the most recent parameters setting presented by Barbulescu and Duquesne [1] for pairing-based cryptography; that are secure enough for 128-bit security level; to explicitly show the quartic twist (d = 4) and sextic twist (d = 6) mapping between the isomorphic rational point groups for KSS (Kachisa-Schaefer-Scott) curve of embedding degree k = 16 and k = 18, receptively. This paper also evaluates the performance enhancement of the obtained twisted mapping by comparing the elliptic curve scalar multiplications.

• Steel and Composite Structures
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• 제18권1호
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• pp.121-134
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• 2015

This paper is to investigate the potentials of the elastic seismic design of twisted high-rise steel diagrid frame buildings in the strong wind and moderate/low seismicity regions. First, the prototypes of high-rise steel diagrid frames with architectural plans that have a twist angle of 0 (regular-shaped), 1, and 2 degrees were designed to resist wind. Then, the effects of the twist angle on the estimated quantities and structural redundancies of the diagrid frames were examined. Second, the seismic performance of the wind-designed prototype buildings under a low seismicity was evaluated. The response spectrum analysis was conducted for the service level earthquake (SLE) having 43-year return period and the maximum considered earthquake (MCE) having 2475-year return period. The evaluation resulted that the twisted high-rise steel diagrid frames resisted the service level earthquake elastically and most of their diagrid members remained elastic even under the maximum considered earthquake.

• Fibers and Polymers
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• 제3권1호
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• pp.31-37
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• 2002

Most fibers are irregular, and they are often subjected to combined loading conditions during processing and enduse. In this paper polyester and wool fibers under the combined tensile and torsional loads have been studied for the first time using the finite element method (FEM). The dimensional irregularities of these fibers are simulated with sine waves of different magnitude and frequency. The breaking load and breaking extension of the fibers at different twist or torsion levels are then calculated from the finite element model. The results indicate that twist and level of fiber irregularity have a major impact on the mechanical properties of the fiber and the effect of the frequency of irregularity is relatively small.

• 감성과학
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• 제5권3호
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• pp.67-74
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• 2002

Testing device was newly designed and built to measure the dynamic contact angle. The measurement was made using microscope interfaced with computerized image analysis system while the dynamic condition being controled using Instron. As specimens for the experiment, two different types of fibers, i.e., hydrophilic and hydrophobic, were prepared. In case of hydrophilic fiber, the increase of twist level gave the increase of contact angle. However, in hydrophobic yarn the increase of twist level gave the decrease of contact angle. When saline was used as a telling liquid, the increase of the concentration gave the increase of contact angle. The results rationalized clearly on the basis of known concepts could be used in designing fabric structure for the improvement of comport performance.

• Journal of the Korean Wood Science and Technology
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• 제21권3호
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• pp.45-52
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• 1993

Surveyed results on the slope of grain and the twist of sawn lumber of Pinus koraiensis, Larix leptolepis, and Pinus densiflora were summarized as follows: 1. The slope of grain of Pinus koraiensis has a Z-grain in the stem axis. The slope of grain was found to be the lowest at near to the pith and then constantly increased. At the height of 0.2m from the base of stem. a cross section of 35 annual rings was found to have a repeatedly increasing and decreasing slope of grain and then constantly decreased. At the height of 1.2m to 7.2m from the base of stem, the slope of grain increased conspicuously until the 10th annual ring, after which it increased near to the bark with repeatedly increasing and decreasing trends. 2. Pinus densiflora has a S-grain in the stem axis. The lowest slope of grain was found at near to the pith, and the highest in the 10 to 35 annual rings from the pith. 3. Larix leptolepis has a S-grain. At the height of 3.2m from the base of stem, the big fluctuation of the slope of grain was found without any particular trend. 4. The slope of grain and the twist between natural and reforested timber of Pinus koraiensis were found to be almost the same trend in viewpoint of the annual ring. The maximum slope of grain of imported Siberian timber of Pinus koraiensis was found at the 10 annual rings, which was quite similar to that of native species in Korea, but the big difference of the twist was found at 140 annual rings. 5. The twist was little at the mature wood of reforested Pinus koraiensis and Siberians and the duplicated part of mature and juvenile woods of those. On the contrary, the twist was great at the duplicated part of mature and juvenile woods of Pinus koraiensis. 6. The twist of Larix leptolepis showed the S-direction which coincided with that of slope of grain. The twist was greatest at the part of juvenile wood and little at the duplicated part of mature and juvenile woods, and little difference of twist was found between mature and juvenile woods. 7. Siberian larix having a minimum slope of grain showed the lowest twist, and the twist at the duplicated part of mature and juvenile woods showed a middle level of both mature and juvenile woods' portions.

• 한국전자파학회논문지
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• 제20권4호
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• pp.390-395
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• 2009

본 논문에서는 미앤더 스트립라인을 이용한X-대역 광대역 편파 변환기 설계 및 최적화 문제에 대해서 고찰하였다. 편파 변환기에 입사되는 편파를 수직, 수평 성분으로 분리하고 각 편파별로 등가 전송선 모델(transmission line model)을 사용하여 교차 편파 억제율과 편파 변환율을 계산하였다. 또한, 최적화된 파라미터 도출을 위해 유전 알고리즘과 particle swarm optimization에 기반한 하이브리드 알고리즘의 성능을 평가하고 설계에 적용하였다. 최적화된 편파 변환기는 X-대역(8.45$\sim$11.38 GHz)에서 -25 dB 이하의 편파 억제 성능을 보여주고 있으며, 편파 변환 손실은 0.2 dB 이하로 계산되었다. 또한, 이 결과를 상용 시뮬레이션 수치와 비교 분석하였다.