• Journal of Korean Association for Spatial Structures
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• v.16 no.1
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• pp.73-84
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• 2016

This study analyzes the four composition elements : profile, anchorage and connection, material and member rigidity, stability, as the main composition design elements of flexure structure systems, in order to explore possibilities for more various structure designs in architectures with flexure structure system. It also examines typical design methods that use the mentioned four composition elements. At the results, this research presents an understanding of the differences between funicular shape and non-funicular shape and mechanical features of the shapes in the profile element, regarding to the ratio of rise height to span length(f/l). Also, the typical design methods are presented for the designable usages of the hinge joints and the fix joints, and for the applications of member rigidity expressed by the index of the ratio of member depth to span length(d/l). And it was presented that connection styles, addition of brace members, placement of shear walls are the main design methods in the stability element. This data would be useful to architectural designs concerning integrated design with structures.

• Steel and Composite Structures
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• v.41 no.5
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• pp.713-730
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• 2021

The seismic performance of rigid steel frames is widely investigated, but that of semi-rigid (SR) steel frames are not studied extensively, especially for near-field earthquakes. In this paper, the performances of five and ten-story steel SR frames having different degrees of semi-rigidity are evaluated at four performance points in the four different deformation states, namely, the elastic, elasto-plastic, plastic, and near collapse states. The performances of the SR frames are measured by the response parameters including the maximum values of the top floor displacement, base shear, inter-story drift ratio, number of plastic hinges, and SRSS of plastic hinge rotations. These response parameters are obtained by the capacity spectrum method (CSM) using pushover analysis. The validity of the response parameters determined by the CSM is evaluated by the results of the nonlinear time history analysis (NLTHA) for both near and far-field earthquakes at different PGA levels, which are consistent with the performance points. Results of the study show that the plastic hinges of SR frame significantly increase in the range of plastic to near-collapse states for both near and far-field earthquakes. The effect of the degree of semi-rigidity is pronounced only at higher degrees of semi-rigidity. The predictions of the CSM are fairly well in comparison to the NLTHA.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.6
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• pp.1041-1050
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• 1997

This study was carried out to improve the thermal insulation properties of wool and wool- like fabrics by treating the fabrics with polyethylene glycol, to evaluate the fabric hand of PEG treated wool and wool-like fabrics and to grade up the fabric hand of the treated fabrics by treating with softening agents. Wool and wool-like fabrics were treated with high molecular PEG-8,000 by PDC. The thermal release/storage properties were measured on a DSC. Hand of specimens were evaluated by KES-FB system. The results were as follows; 1. PEG-treated fabrics showed thermal storage and thermal release properties by DSC and the heat contents were generally proportional to the add-ons. 2. PEG-treated fabrics showed higher Koshi and lower Numeri and Sofutosa values due to lower tensile energy and recovery and higher bending rigidity and shear stiffness as the add- ons increased. 3. PEG-treated fabrics showed much lower bending rigidity after softening agents treatment.

• Textile Coloration and Finishing
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• v.14 no.1
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• pp.58-65
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• 2002

This study surveys the physical properties of Solo-spun fabrics related to the characteristics of Solo-spun yarns, which were described in previous reports. For this purposes, 6 kinds of fabrics were woven on the pilot loom. 3 kinds of Solo-spun yarns with the 3 level of twist mutiplier of Nm 1/30 and 3 kinds of conventional ring-spun yarns with the same levels of twist multipliers of the same yarn counts. The fabrics were of 2/2 twill and clear-cut finished. The physical properties were surveyed by means of KES-FB system. Solo-spun fabrics seemed to be stiffer than ring spun fabrics as showing the lower extensibility with higher tensile energy, the higher bending rigidity, and the higher shear rigidity. Solo-spun fabrics showed the lower value in surface friction coefficient and surface roughness. For fabric abrasion tests, Solo-spun fabrics showed the higher pill resistance.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2322-2330
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• 1994

The torsion problem in a cylindrical rod is usually formulated in terms of either the warping function or the Prandtl stress function. In a rod whose cross-section is bounded by circles and rectangles, we develop an analytic solution approach based on the warping function, which satisfies Laplace's equation. The present formulation employs polynomials and The Fourier series-type solutions, both of which satisfy exactly the governing differential equation. Using the present method, the maximum shear stress and torsional rigidity are efficiently and accurately calculated and the present results are compared with those by other methods. The specific numerical examples include the case with eccentric holes which was investigated earlier. The finite element results are also compared with the present results.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1079-1089
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• 1998

Various fabrics, including natural fibers, regenerated cellulosic fibers, synthetic fibers, blend yarn, and mixture fabrics, were treated with the solutions of high purity chitosan in 1% acetic acid, having high viscosity of 930cps or low viscosity of 8cps. Physical/ mechanical properties of the treated fabrics samples were measured using Kawabata Evaluation System and drape tester. From these, hand values and total hand values of the fabric samples were calculated using Kawabata-Niwa translation equations. KOSHI, SHARI, HARI values have increased for the treated samples, while FUKURAMI values have decreased in general.

• Fashion & Textile Research Journal
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• v.6 no.3
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• pp.393-398
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• 2004

This research offers recycling method of NaOH from mercerizing process of cotton fabric. The measuring system of NaOH concentration was designed for the mercerizing process and tested for various conditions which can be occurred in factory. The accuracy of the system was varied as the testing condition was changed. As the concentration of sulfuric acid used for titrating NaOH decreased, the accuracy of measuring system increased. The concentration of NaOH for waste water collected from mercerizing process was measured by 5.2%. As the ratio of newly mixed NaOH increased, moisture regain. water absorbency and whiteness of the specimen increased. The bending rigidity(B) and shear rigidity(G) decreased, as the ratio of newly mixed NaOH increased.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.251-256
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• 2015

In this paper, an systematic approach is presented, in which the bridge-type traffic sign structure is body out by CSDDA PrePost Processor. There is dead load and wind load that is working on the structure which will make force and moment. Analyzied the stress distribution of the standard form and by changing the shape, compared the safety in terms of deflection and stress (with the standard form) to know the effect of each component in the bridge-type traffic sign structure. The safety of deflection and stress is evaluated by maximum distance/100) and ASIC code respectively. The standard form of bridge-type traffic sign structure is established by two pairs of pillar and two pairs of floor beam. Replaced the links which is consist of flange and screws as the torsion spring and nm our analysis program. By adjusting variable of rigidity modulus of torsion spring, moment between column and beam is controled depending on value of rigidity modulus.

• Steel and Composite Structures
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• v.19 no.2
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• pp.467-484
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• 2015

Seismic performances of dual steel moment-resisting frames with mixed use of rigid and semi-rigid connections were investigated to control of the base shear, story drifts and the ductility demand of the elements. To this end, nonlinear seismic responses of three groups of frames with three, eight and fifteen story were evaluated. These frames with rigid, semi-rigid and combined configuration of rigid and semi-rigid connections were analyzed under five earthquake records and their responses were compared in ultimate limit state of rigid frame. This study showed that in all frames, it could be found a state of semi-rigidity and connections configuration which behaved better than rigid frame, with consideration of the base shear and story drifts criterion. Finally, some criteria were suggested to locate the best place of the semi-rigid connections for improvement of the seismic performance of steel moment-resisting frames.

• Structural Engineering and Mechanics
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• v.8 no.6
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• pp.607-622
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• 1999

Being a significant mode of deformation, shear effect in addition to the other modes of stretching and bending have been considered to develop two finite element models for the analysis of beams on elastic foundation. The first beam model is developed utilizing the differential-equation approach; in which the complex variables obtained from the solution of the differential equations are used as interpolation functions for the displacement field in this beam element. A single element is sufficient to exactly represent a continuous part of a beam on Winkler foundation for cases involving end-loadings, thus providing a benchmark solution to validate the other model developed. The second beam model is developed utilizing the hybrid-mixed formulation, i.e., Hellinger-Reissner variational principle; in which both displacement and stress fields for the beam as well as the foundation are approxmated separately in order to eliminate the well-known phenomenon of shear locking, as well as the newly-identified problem of "foundation-locking" that can arise in cases involving foundations with extreme rigidities. This latter model is versatile and indented for utilization in general applications; i.e., for thin-thick beams, general loadings, and a wide variation of the underlying foundation rigidity with respect to beam stiffness. A set of numerical examples are given to demonstrate and assess the performance of the developed beam models in practical applications involving shear deformation effect.