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Presents an alternative lower bound to the elastic buckling collapse of thin shells of revolution, in comparison with results from geometrically non‐linear elastic…
Presents an alternative lower bound to the elastic buckling collapse of thin shells of revolution, in comparison with results from geometrically non‐linear elastic analysis. The numerical finite element method is based on axisymmetric rotational shell elements whose strain‐displacement relations are described by Koiter’s small finite deflection theory, with displacements expanded circumferentially using a Fourier series. First, compares the reduced stiffness linear analysis, based on the buckling equation without incremental linear in‐plane energy components corresponding to the lowest eigenmode (for a particular cylindrical shell under external pressure), with the results obtained by Batista and Croll. Second, the non‐linear astatic (quasi‐static) elastic analysis to clamped spherical caps under uniform external pressure is carried out in order to compare the results from a reduced stiffness analysis from viewpoints of not only buckling loads, but also total potential energy. Argues that the astatic buckling loads may relate to reductions due to a specific imperfection effect on elastic buckling collapses.
Reinforced concrete (R/C) hyperbolic cooling towers are the largest thin‐shell structures ever constructed. These towers stand more than 150m tall and have wall…
Reinforced concrete (R/C) hyperbolic cooling towers are the largest thin‐shell structures ever constructed. These towers stand more than 150m tall and have wall thicknesses of 0.20‐0.25m. Therefore, these can be classified as thin‐shell structures. Analyses the influences of both the reinforcing ratio and the tensile strength of the concrete on the strength of the R/C cooling tower shells. In the numerical analysis Port Gibson tower is adopted for the numerical model and the finite element method is applied to examine the non‐linear behaviour of the cooling tower shells. From the load displacement curves the initial crack strength and the ultimate strength are determined. Also presents the stress redistribution processes and demonstrates the influences of these problems on the strength of the cooling tower shells.
This paper seeks to present a case study of a rural Do It Yourself (DIY) Information and Communication Technology (ICT) project in a Japanese depopulated rural community.
The paper consists of two parts. First, the technology that enables the project is presented together with policy considerations about why such a technology had to be deployed. An analysis of the results from surveys and interviews is then presented.
In order to achieve sustainable development of a rural ICT project, which is the key to enabling economic development, it is essential to involve residents' participation. A test‐bed DIY project was constructed in a Japanese rural community in 2004, and surveys were conducted in 2004 and 2006 in order to identify residents' needs and awareness of ICT, determine the information literacy level, and evaluate the attitude toward the acceptance of ICT. Also, individual interviews were conducted to look at the qualitative side of residents' perceptions. In general, the residents were found to be indifferent as far as the statistical significance is concerned. However, insights from individual interviews disclosed some useful factors about how to tackle the digital divide in modern society, including the usefulness of DIY in ICT.
The findings, based on analysis of a unique DIY ICT project, will be of value to operators and regulators.
What were the spinning industries like in the initial stage in Japan? From which class did the founders of these industries come, ex‐warrior or commoners (merchants or…
What were the spinning industries like in the initial stage in Japan? From which class did the founders of these industries come, ex‐warrior or commoners (merchants or farmers)? This will interest readers. Viewed from a capital investment, it was most significant in Japan whether the government financed an industry or not. This article deals with Tanigawa Tatsumi, the founder president (presidency 1885‐1911) of Okayama Cotton Spinning Company (an enterprise for employing ex‐warriors). Whereas cotton spinning companies for employing ex‐warriors played an important role in the initial stages of the development of the cotton spinning industry, these became bankrupt before long. Under such circumstances, Tanigawa’s Spinning Company weathered many years. An examination of a brief history of Okayama Spinning Company with special reference to Tanigawa’s life history will reveal the significance of the entrepreneur’s learning and virtue, organizing ability, and leadership. Furthermore, it will make clear what otherwise might have been overlooked about the initial nature of industrialization in Japan.
The traditional Japanese cotton-crepe fabric chijimi has been used for summer clothing for over a century because of its good skin comfort. The high extensibility of this…
The traditional Japanese cotton-crepe fabric chijimi has been used for summer clothing for over a century because of its good skin comfort. The high extensibility of this fabric relies on the high-twist cotton yarns used in the weft direction. The purpose of this paper is to show the effect of environmental humidity on the extensibility of highly twisted cotton yarns to help in choosing weft yarn suitable for woven fabric.
Four highly twisted cotton yarns are examined under 10-90 percent RH and in 25°C water. Cyclic tensile tests are performed to obtain the tensile energy, resilience, extensibility at maximum applied load (EM), and residual strain.
Comparing the same yarn-count samples Y1 and Y2, the EM of Y2 (2,200 T/m) is larger than that of Y1 (1,000 T/m) under all RH conditions, and the difference increases at humidity over 60 percent RH. For fabric crepe samples woven by Y1 (warp) and Y2 (weft), the extensibility (EM-1) in the weft direction is in the range 16-26 percent, which is equivalent to that of outer-knitted fabrics. The extensibility and recovery of chijimi is largely dominated by the twist of weft yarns, which is also influenced by changes in relative humidity.
The skin comfort of Takashima chijimi has been of interest, but the high extensibility of this cotton fabric has not been given much attention. The results of this study show that yarn twist is key to controlling extensibility in high-humidity environments.