• Steel and Composite Structures
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• v.37 no.4
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• pp.431-446
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• 2020

This paper presents the flexural performance of double skin composite beams (DSCBs) at different Arctic low temperatures. 12 DSCBs were prepared and tested under two-point loading at different Arctic low temperatures of 20, -30, -50, and -70℃. The studied parameters include low-temperature level (T), steel-faceplate thickness (t), shear span ratio (λ), and spacing of headed studs (S). The experimental investigations under two-point loading tests showed that flexural failure occurred to all DSCBs, even including the specimen designed with the small λ ratio of 2.9. The ultimate strength behaviours of DSCBs were improved due to the improved mechanical properties of constructional materials and the confinement on shear connectors. The DSCB subjected to two-point loading and low temperatures exhibits a five-stage working mechanism. The stiffness and strength indexes of DSCBs increase linearly with temperature and t value increasing, while decreasing as shear span ratio boosts. In the contrast, the change of S value from 150 to 200 mm has little effect on the ultimate strength behavior of DSCB.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.10B
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• pp.1876-1884
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• 1999

The next generation of wireless LAN AND PBX systems will make use of the unlicensecd band at 2.5 GHz. Deployment of these systems inside buildings requires and understanding of propagation characteristics within buildings. Because the wavelength is small compared to building dimensions, ray methods can be used to predict propagation, but they require knowledge of the transmission and reflection properties of walls. This paper reports on transmission measurements made at walls made of gypsum board on metal studs, and at concrete block walls using directive antennas. The measurements are found to give good agreement with theoretical results that account for the periodic nature of the wall structure.

• Computers and Concrete
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• v.2 no.4
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• pp.249-266
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• 2005

In the present paper a transient three-dimensional thermo-mechanical model for concrete is presented. For given boundary conditions, temperature distribution is calculated by employing a three-dimensional transient thermal finite element analysis. Thermal properties of concrete are assumed to be constant and independent of the stress-strain distribution. In the thermo-mechanical model for concrete the total strain tensor is decomposed into pure mechanical strain, free thermal strain and load induced thermal strain. The mechanical strain is calculated by using temperature dependent microplane model for concrete (O$\check{z}$bolt, et al. 2001). The dependency of the macroscopic concrete properties (Young's modulus, tensile and compressive strengths and fracture energy) on temperature is based on the available experimental database. The stress independent free thermal strain is calculated according to the proposal of Nielsen, et al. (2001). The load induced thermal strain is obtained by employing the biparabolic model, which was recently proposed by Nielsen, et al. (2004). It is assumed that the total load induced thermal strain is irrecoverable, i.e., creep component is neglected. The model is implemented into a three-dimensional FE code. The performance of headed stud anchors exposed to fire was studied. Three-dimensional transient thermal FE analysis was carried out for three embedment depths and for four thermal loading histories. The results of the analysis show that the resistance of anchors can be significantly reduced if they are exposed to fire. The largest reduction of the load capacity was obtained for anchors with relatively small embedment depths. The numerical results agree well with the available experimental evidence.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.4
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• pp.95-104
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• 2018

This study classified the figurative features of the raglan sleeves presented in the Spring and Summer Collections and Fall and Winter Collections abroad in 2010 and 2018 and analyzed the production methods and patterns of the classified raglan sleeves. The analysis results are described below. The raglan sleeves in the latest fashion trends were classified into Type H, Type A, Type O and Type Y per shape. The production features of raglan sleeves in the latest fashion trends included the cutting lines in various shapes, a flounce that made shoulders look wider, and decorations such as gathers, studs, punching, slits, pleats and tucks. The raglan sleeve design was classified into Yoke Raglan, Armhole Princess Raglan, Semi Raglan, Gathered Raglan, Pleats Raglan, Cowl Raglan, Origami Raglan, Circular Curved Raglan, Capes Raglan and Constructive Design Raglan and the patterns per design were presented. For creative and experimental clothing by the analysis of the features of raglan sleeve structure, a variety of configuration methods need to be developed and implemented. The analysis results of this study will contribute to the development of the fashion industry through small quantity batch production pursuing unique styles as the basis for further study on the configuration methods of raglan sleeves. This study will be used in various ways as education materials on sleeve patterns in the educational field. Through the analysis of sleeve patterns, this study tries to provide basic data for planning the design of raglan sleeves and helping to diversify the ladies' apparel market in the future.