• Steel and Composite Structures
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• v.18 no.1
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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.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.223-230
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• 2014

In this paper, the wind-induced response characteristics of freeform shaped tall building is studied by using FSI analysis. The analytical models are twist shaped ones at representing type of atypical tall building, and this study focused on the relationship between twist angle and wind acceleration. Firstly, 1-way FSI analysis is performed, so maximum lateral displacement of the analytical model for 100 years return period wind speed is calculated, then the elastic modulus of a structure that satisfies the constraints condition is evaluated. And 2-way FSI analysis is carried out. so acceleration of the analytical model for the evaluated modulus of elasticity and arbitrary density is predicted through time history analysis. The basic model is a set of a square shape, height is 400m, slenderness ratio is 8, and twist model is rotated at square model from 0 to 90 degrees at intervals of 15 degrees and from 90 to 360 degrees at intervals of 90 degrees. According to the result of predicting wind acceleration by the shape of each model, the wind vibration effect of square shape model is confirmed to be sensitive more than a twist shape ones.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.102.1-102.1
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• 2011

In this study we use three-dimensional magnetohydrodynamic simulations to investigate how the dynamic state of emerging magnetic field is related to the twist of field lines. Emerging magnetic field forms a magnetic structure on the Sun where various kinds of activity such as solar flares, jets, and coronal mass ejections are observed. To understand the physical mechanism for producing such activity, we have to know the dynamic nature of this structure. Since flares are the manifestation of rapidly dissipating electric current in the corona, we also investigate the distribution of current density inside the structure and examine how it depends on the field-line twist. To demonstrate the dynamic structure of emerging magnetic field, we focus on the factors characterizing the geometric property and stratification of emerging magnetic field, such as the curvature of field line and the scale height of field strength. These two factors show that emerging field forms a two-part structure in which the central part is close to a force-free state while the outer marginal part is in a fairly dynamic state where magnetic pressure force is dominant. We discuss how the field-line twist affects the two-part structure and also explain a possible relation between electric current structure and sigmoid observed in a preflare phase.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.145-149
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• 2023

In this study, the spectrum changes induced from the doping of phosphor micro particles in a twist nematic liquid crystal cell was observed. The experimental results show that the achromatic transmission can be observed with a proper driving condition, which may be applied to the design of an achromatic liquid crystal device. In this paper, we tried to figure out the spectrum changes induced from the doping of phosphor micro particles. The experimental result of the phosphor powder doped twist nematic liquid crystal cell shows that the achromatic transmission and the wavelength linearly dependent transmission both can be observed with some proper driving conditions, respectively. The result is useful on developing an achromatic liquid crystal device and it can be applied for Vihicle lamp.

• Journal of the Optical Society of Korea
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• v.2 no.1
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• pp.34-37
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• 1998

We present a novel method for the stabilization of the Sagnac current sensor with active twist control. The sensor output was improved more than 8 times by employing the proposed stabilization method. Stability within $\pm$1.7% was demonstrated between 36$^{\circ}C$ and 62$^{\circ}C$.

• Composites Research
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• v.29 no.6
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• pp.369-374
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• 2016

In this study, a structural optimal design of 10 MW composite blade was performed using bend-twist coupled(BTC) design concept. Bend-twist coupling of blade means the coupling behavior between the bending and torsional deflections due to the composite lamina with fiber angle biased from the blade longitudinal axis. This can potentially improve the overall performance of composite blade and reduce the dynamic loading. Parametric studies on layup angle, thickness and area of off-axis carbon UD were conducted to find the optimum coupling effect with weight reduction. Comparing the results of fatigue load analysis between conventional model and BTC applied model, the damage equivalent load(DEL) of blade root area were decreased about 3% in BTC model. To verify the BTC effect experimentally, a 1:29 scaled model was fabricated and the torsion at the tip under deflection behavior of blade stiffener model was measured by static load test.

• Textile Coloration and Finishing
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• v.11 no.2
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• pp.9-18
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• 1999

In order to establish fundamental data for the betterment of Polyester microfiber fabric handle, a study by using fixed warp of ITY yarn samples with P/F, DTY, and ITY weft yarns was performed. For this purpose the samples of total 27 kinds were prepared. That is, each sample yarn was twisted in three ways and for each twisted yarn the fabric structures were modified in three ways, plain, twill, and satin. The examination was done by focusing on the point of the change of handles and the characteristics of the mechanical properties of the samples with the change of yarn and the fabric structure. The handles and the mechanical properties were examined with the KES-F system suggested by Kawabata. The results were as follows : 1. WT and MIU increased with increasing the twist. By comparing WT and MIU by yarn, DTY was higher than P/F. It appeared that twill and satin were higher than plain. 2. The bending rigidity change in DTY with increasing the twist was not significant, however in P/F it appeared apparently decreased with increasing the tlvist. Also, it appeared that when using P/F as weft the bending rigidity was higher than when using DTY and the twill structure appeared higher than the satin structure. 3. In shear force the increasing rates of plain and the twill were higher than satin. When DTY and P/F were used as weft, the shear force was higher in ITY and DTY than in P/F case. 4. Koshi appeared higher in the order of plain, twill and satin. When DTY and P/F were used as the weft Koshi increased with increasing the twist in plain, however in twill and satin it appeared to decrease. In hand value ITY(=7.5) appea.ed to be highe. than DTY and P/F(=6.5). 5. In all cases Shinayakasa decreased with increasing the twist. The hand values observed that satin was =4, twill was =3, and plain was =1.5. 6. Fukurami showed no significant change with increasing the twist in DTY, however in P/F and ITY it decreased.

• Journal of Veterinary Clinics
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• v.39 no.4
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• pp.149-155
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• 2022

The aim of this study was to compare the mechanical properties of 0.6 and 0.8 mm cerclage wires with the 1.0 mm cerclage wire in the twist, single-loop, double-loop, double-wrap, and loop/twist knot methods. Six stainless steel cerclage wires of various diameters in different knot methods were tied round a customized jig mounted on a load testing machine. The initial tension, initial stiffness, and yield load were evaluated. The failure mode of each cerclage was observed. For each wire size, the double-loop, double-wrap, and loop/twist knots showed significantly greater initial stiffness, and yield load than those seen with twist and single-loop knots. The single-loop knot showed the least initial stiffness regardless of the diameter. As the cerclage wire diameter increased, the cerclage tended to show significantly greater initial stiffness, and yield load. Failure modes varied depending on the knot configurations. Single-loop knots of smaller-diameter wires less than 1 mm had similar or lower initial tension, initial stiffness, and yield load than a twist knot. Owing to the variance in mechanical properties, the clinical application of the knot type should depend on the diameter of the cerclage wire.

• Korean Journal of Plant Resources
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• v.31 no.1
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• pp.71-76
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• 2018

This study was conducted to investigate the effect of shoot twist on fruitfulness and fruit quality of 'Campbell Early' grapevine. Proper pruning and training are essential to produce a good yield of high-quality fruit and to maintain the balance between vegetative growth and fruiting. The most common problem in spur-pruned 'Campbell Early' cultivar is that vigorous buds has low fruitfulness and thereby the shoot become more vigorous the following spring because of lower crop load. Therefore, shoot twists in very vigorous 'Campbell Early' canes (above 10.0 mm) were performed on the third nodes and the $7^{th}$ nodes of each shoot at 7 days before bloom and full bloom, respectively. Sprouting date, blooming date were not significantly different among the treatments while, harvesting date was delayed approximately 3 days. However, number of berries per cluster, cluster weight and fruitfulness were significantly higher in the shoot twist treatment on the third nodes than the control that was topping alone. Combination treatments of shoot twist and topping had an additive effect on increasing cluster weight resulting in higher increase of yield by 12.1 ㎏ per vine. These results indicated that the shoot twist on very vigorous canes of 'Campbell Early' grapevine for well fruitfulness seemed to be very effective.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.4
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• pp.1851-1857
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• 2014

Objective: The main purpose of this work was to investigate the effect of berberine hydrochloride (BH) on the proliferation, apoptosis, migration, and invasion of CNE-1 nasopharyngeal carcinoma cells. Our results shed light on the functional components of traditional Chinese herbs for potential use in modern medicine. Methods: The CNE-1 cell line was treated with different concentrations of BH and effects on cell viability and proliferation were evaluated using the Cell Counting Kit-8 (CCK-8) assay. Anti-migratory and anti-invasive actions of BH were investigated using wound healing assays and the Millicell Hanging cell culture insert system, respectively. Expression of the epithelial-mesenchymal transition (EMT)-related gene twist (Twist) was analyzed by real-time PCR and Western blotting. Apoptosis was estimated with an annexin-V fluorescein (FITC) apoptosis detection kit, as well as with reference to levels of activated caspase-3 of CNE-1 cells before and after treatment with BH utilizing fluorescence spectroscopy. Results: BH was capable of reducing proliferation and viability of CNE-1 cells in a dose- and time-dependent manner, also demonstrating anti-migratory and anti-invasive capacities which correlated with reduction in expression of Twist. Finally, BH was able to induce significant amounts of apoptosis in CNE-1 cells, as demonstrated by an increase in the activity of caspase-3 and in annexin-V staining following treatment. Conclusion: BH extracted from rhizoma coptidis demonstrated an ability to block proliferation, induce apoptosis, and impair the migration and invasion of the CNE-1 cell line Considering these properties, our results suggest that BH could be an important compound for consideration in the treatment of nasopharyngeal carcinoma.