• Structural Engineering and Mechanics
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• v.61 no.2
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• pp.245-253
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• 2017

The increasing lack of good quality soils allowing the development of roadway, motorway, or railway networks, as well as large scale industrial facilities, necessitates the use of reinforcement techniques. Their aim is the improvement of the global performance of compressible soils, both in terms of settlement reduction and increase of the load bearing capacity. Among the various available techniques, the improvement of soils by incorporating vertical stiff piles appears to be a particularly appropriate solution, since it is easy to implement and does not require any substitution of significant soft soil volumes. The technique consists in driving a group of regularly spaced piles through a soft soil layer down to an underlying competent substratum. The surface load being thus transferred to this substratum by means of those reinforcing piles, which illustrates the case of a piled embankment. The differential settlements at the base of the embankment between the soft soil and the stiff piles lead to an "arching effect" in the embankment due to shearing mechanisms. This effect, which can be accentuated by the use of large pile caps, allows partial load transfer onto the pile, as well as surface settlement reduction, thus ensuring that the surface structure works properly. A technique for producing rigid piles has been developed to achieve in a single operation a rigid circular pile associated with a cone shaped head reversed on the place of a rigid circular pile. This technique has been used with success in a pile-supported road near Bourgoin-Jallieu (France). In this article, a numerical study based on this real case is proposed to highlight the functioning mode of this new technique in the case of industrial slabs.

• Journal of the Korean GEO-environmental Society
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• v.9 no.5
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• pp.53-59
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• 2008

The purpose of the study was to evaluate how much gastropod shell effected its properties better than crushed stone as coarse grained materials by comparing friction properties of a contact surface between coarse grained materials and geosynthetics with the large-scale direct shear test. To achieve the purpose, the study compared and analyzed friction coefficient and friction angle by making crushed stone or gastropod shell into model ground and by installing and shearing non-woven fabric or geostrip geosynthetics. As the results of the analysis, crushed stone had the internal friction angle of $33.8^{\circ}$ when its unit weight was $13.7kN/m^3$ and gastropod shell had the internal friction angle of $35.4^{\circ}$ when its unit weight was $5.4kN/m^3$. Also, the friction angle of a contact surface between geosynthetics and crushed stone was larger than the friction angle of a contact surface between geosynthetics and gastropod shell.

• The International Journal of Costume Culture
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• v.8 no.1
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• pp.23-31
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• 2005

Mechanical properties and hand evaluation of wool/acrylic(W/A) blend knits were conducted before and after repeated washing to get the optimum W/A blending ratio, which could help achieve the optimum mechanical and hand properties of the knits. The five test fabrics using the yarns with different W/A blending ratios($\%$), 100/0, 70/30, 50/50, 30/70, 0/100, were knitted. The fabrics were washed by a rotating drum type washing machine. Then, objective mechanical and hand properties were evaluated by KES-FB, Kawabata evalution system for fabric. The results are as follows: there was no change in the hand value of the knitted fabric with the W/A-blended yarn caused by the change in the blending ratio before washing. After washing, however, the increase of acrylic's blending rate caused the bending property to decrease proportionally, while the friction coefficient of the surface property increased. Furthermore, the study showed that W/A 50/50 possesses the most superior tensile property and shearing property, which could attain the optimum blending ratio. Similar results in hand value were derived in all the samples. After washing, however, the increase in acrylic's blending rate caused a proportional decrease in KOSHI and an increase in FUKURAMI. In addition, W/A 50/50 gained the biggest NUMERI value, again corresponding to the optimum blending ratio. Similar results in total hand value were derived in all the samples before washing. After washing, though, all the total hand values decreased, and, as the wool fabric's blending rate increased, the total hand values proportionally decreased further.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.2 s.161
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• pp.197-205
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• 2007

We investigated the effects of washing on the mechanical properties and hand values of spandex/cotton and cotton single jersey fabrics. These knitted fabrics were subjected to 30 laundering cycles with a drum-type washer and were followed by drying at $65^{\circ}C$ with a tumble dryer. The mechanical properties of the cotton knitted fabrics changed greatly during the first washing and then suffered no further change in their properties as the number of washing cycle increased. However, the properties of the spandex/cotton knitted fabrics changed continuously throughout all the washing cycles. The cotton/spandex knitted fabrics showed higher values in tensile and bending properties than did the cotton knitted fabrics, though both kinds of fabrics showed less difference in shearing, surface and compression properties. The spandex/cotton knitted fabrics which had proper density had a higher THV for winter underwear after 30 repeated washings than did the cotton knitted fabrics, and the THVs of both fabrics decreased with the increase in the number of washing cycles.

• International Journal of Fluid Machinery and Systems
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• v.4 no.4
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• pp.387-395
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• 2011

Single-blade centrifugal pumps are widely used as sewage pumps. However, the impeller of a single-blade pump is subjected to strong radial thrust during pump operation because of the geometrical axial asymmetry of the impeller. Therefore, to improve pump reliability, it is necessary to quantitatively understand radial thrust and elucidate the behavior and mechanism of thrust generating. This study investigates the radial thrust acting up on a single-blade centrifugal impeller by conducting experiments and CFD analysis. The results show that the fluctuating component of radial thrust increases as the flow rate deviates from the design flow rate to low or high value. Radial thrust was modeled by a combination of three components, inertia, momentum, and pressure by applying an unsteady conservation of momentum to the impeller. The sum of these components agrees with the radial thrust calculated by integrating the pressure and the shearing stress on the impeller surface. The behavior of each component was shown, and the effects of each component on radial thrust were clarified. The pressure component has the greatest effect on the time-averaged value and the fluctuating component of radial thrust. The time-averaged value of the inertia component is nearly 0, irrespective of the change in the flow rate. However, its fluctuating component has a magnitude nearly comparable with the pressure component at a low flow rate and slightly decreased with the increase in flow rate.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.10
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• pp.1467-1477
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• 2002

This study was investigated physical properties of stretch fabrics by KES-FB system to show suitable basic data to making skirts of excellent capacity and develop more organized basic skirt pattern by fitness evaluation. 1. The results of T. H. V.(Total Hand Value) were as followa: In the kind of blending fiber, cotton/spandex was more excellent than nylon/spandex and polyester/spandex, in the direction of stretch, one-way(weft inserted polyurethan yarn) polyester/spandex and cotton/spandex were higher than two-way(warp and wet inserted polyurethan yarn) polyester/spandes and cotton/spandex, two-way nylon/spandex was higher than one-way nylon/spandex. 2. The results of calculating the variance between sample stretch fabrics and Japanese s/s women's suit fabrics after standardizing were as follows: Stretch fabrics has 2 range of tensile, bending, shearing, compression, surface, thickness and weight as compared with Jpanese s/s women's suit fabrics. In the tensile property, one-way stretch fabrics were almost the same with Japanese s/s women's suit fabrics, only two-way polyester/spandex had+1～+2 range. In the bending, shear property, there was no difference between sample fabrics and Japanese s/s women's suit fabrics 3. In the total fitness of the skirt, nylon/spandex is the best in the fabrics and one-way stretch fabric is better than two-way strethch fabric.

• Textile Coloration and Finishing
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• v.17 no.3 s.82
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• pp.8-15
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• 2005

Cationic dyeable polyester(CDP) fabric was annealed at varying temperatures range from $120^{\circ}C$ to $220^{\circ}C$ for 1, 3, and 5 min under tension. Dyeing rates of CDP fabrics were measured with cationic and disperse dyes at $100^{\circ}C$ and $120^{\circ}C$ in water system. Also X-ray diffraction pattern, DSC thermograms and dyeability of fabric with cationic and disperse dyes were investigated. The intensities of X-ray diffraction peaks of annealed fabric were increased with increasing in annealed temperature, and peak became sharp with heat setting temperature. The apparent color depth (K/S) of CDP fabric initially decreased with increase of heat-setting temperature up to $160\~180^{\circ}C$ and then increased at higher temperature. The shearing modulus(G) and surface roughness were increased with annealing temperature.

• Journal of the Korean Society of Costume
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• v.58 no.4
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• pp.26-34
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• 2008

The purpose of this study was to create a database of information on the mechanical properties of two different waterproof and breathable shell fabric groups(high density woven and PTFE laminate) used for outdoor apparel and to compare and correlate data of their mechanical properties and hand values. The results of this study were as follows; There were no statistically significant differences between two fabric groups in extension, bending and shearing properties. There were statistically significant differences between two fabric groups in MMD, SMD, LC and we values. High density woven fabrics had smoother surface than PTFE laminated fabrics. PTFE laminated fabrics can be compressed easily more than high density woven fabrics but their recovery after compression was not better than high density woven fabrics. There were statistically significant differences between two fabric groups in NUMERI, FUKURAMI. There was statistically significant difference between two fabric groups in total hand value. Total hand value and mean deviation of MIU had a very high and statistically significant negative correlation coefficient.

• Tribology and Lubricants
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• v.32 no.1
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• pp.18-23
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• 2016

The effective case depth for case-hardened rolling bearing has been discussed. For this purpose, rolling contact fatigue tests for ball bearings built with inner race of various hardness values were conducted until L₁₀ calculating rating life using a bearing life test machine under radial loading. Then, the distribution of residual stress below the inner raceway, which depended on the hardness value, was measured by X-ray diffraction. As a result, the linear relationship was established between the hardness value of the inner race and the theoretical shear stress evaluated at the depth where the residual stress disappeared below the inner raceway. Based on the relationship, it could be found that the factor of safety in bearing manufacturer’s rules for the effective case depth of case hardened rolling bearings was set higher. However, it could be also found that the hardness values at the depth where the maximum shearing stress acted below the raceway surface in a tapered roller bearing hardened by the carburizing process, were not sufficient for preventing plastic deformation under the basic dynamic load rating. Consequently, further efforts were still required to reduce or to disperse the contact load on the material design of a rolling bearing in order to prolong its life.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.441-446
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• 2005

Sole reconstruction should consider both functional and aesthetic aspects; durable weight bearing surface, adequate contour for normal footwear, protective sensation and solid anchoring to deep tissue to resist shearing. The anterolateral thigh perforator free flap has such favorable characteristics as long pedicle, reliable perforators and minimal donor site morbidity. This flap can be safely thinned to 3-4 mm. It can also be elevated with sufficient bulk with muscles like vastus lateralis for complex defect. Between June 2002 and December 2004, 48 cases of sole reconstruction were performed with anterolateral thigh perforator free flaps. Follow up period ranged from 4 to 34 months with a mean of 14.7 months and with exception of one case, all flaps survived. One case of total flap loss was noted due to infection in a patient who was administered lifetime immunosuppressant. Partial necroses developed in three cases but were treated conservatively. Satisfactory aesthetic and functional results were achieved and acceptable gait recovery was noted. Seventy-eight percent of the patients regained protective sensation by 6 months and earlier sensory recovery was noted in sensate flap group. The authors also present a standardized protocol for preoperative patient evaluation and postoperative management and rehabilitation.