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Sewing thread is one of the most important components of a sewn product that contributes significantly in the useful life of a product. Stitch class 504 is the one which is used in all types of sewn products. Its thread consumption is higher than class 300 and class 400. A mathematical model to predict the sewing thread consumption of stitch class 504 has been proposed in this paper. The model is based on the geometry of the stitch. The proposed model takes into account material thickness and stitch density. The model was validated by using 24 samples (with different material thickness and stitch densities). The accuracy of the model was found to be 99%. Sensitivity analysis revealed that stitch density has 62% effect and material thickness has 38% effect on thread consumption. The proposed model can predict the thread consumption accurately; therefore, it can be used for better estimation of required thread and encourage its better utilization in sewn product industry. 相似文献
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Sardar Muhammad Bilal Atta ur Rehman Khan Samee Ullah Khan Sajjad A. Madani Babar Nazir Mazliza Othman 《Wireless Personal Communications》2014,77(4):2497-2515
Over the last few years, vehicular ad hoc networks (VANETs) have gained popularity for their interesting applications. To make efficient routing decisions, VANET routing protocols require road traffic density information for which they use density estimation schemes. This paper presents a distributed mechanism for road vehicular density estimation that considers multiple road factors, such as road length and junctions. Extensive simulations are carried out to analyze the effectiveness of the proposed technique. Simulation results suggested that, the proposed technique is more accurate compared to the existing technique. Moreover, it facilitate VANET routing protocols to increase packet delivery ratio and reduce end-to-end delay. 相似文献
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Spark plasma sintering (SPS) is a high current, low voltage process. Nevertheless, the system voltage (3–10 V) can be large enough to produce significant fields across a thin, insulating sample. A lumped circuit model is analyzed to estimate the magnitude of this field in terms of the die geometry. Normalizing the sample voltage with respect to the system voltage, and the die wall thickness to the punch radius preserves generality of the results. It is predicted that if the latter ranges from 0.15 to 0.25, then 30% of the system voltage may be expressed across the sample. Thus, a sample thickness of about 1–2 mm may experience a field of 10–30 V/cm, which would be large enough to induce field‐assisted sintering in yttria‐stabilized zirconia. The results are corroborated with finite element analysis. The contact resistance is assumed to be negligible; finite values of the contact resistance would lead to fields that are higher than predicted. 相似文献
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Silicon - Silicon (Si) is very effective in the amelioration of heavy metal (HM) stress in different crop plants. This investigation was conducted to assess the protective role of Si in modulating... 相似文献
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The present study utilizes the radial basis functions technique for the estimation of monthly mean daily values of solar radiation falling on horizontal surfaces and compares its performance with that of the multilayer perceptrons network and a classical regression model. In this work, we use solar radiation data from 41 stations that are spread over the Kingdom of Saudi Arabia. The solar radiation data from 31 locations are used for training the neural networks and the data from the remaining 10 locations are used for testing the estimated values. However, the testing data were not used in the modeling or training of the networks to give an indication of the performance of the system at unknown locations. Results indicate the viability of the radial basis for this kind of problem. 相似文献
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Andrea M Rehman Beryl P Gladstone Valsan P Verghese Jayaprakash Muliyil Shabbar Jaffar Gagandeep Kang 《Nutrition journal》2009,8(1):44
Background
Poor growth of children in developing countries is a major public health problem associated with mortality, morbidity and developmental delay. We describe growth up to three years of age and investigate factors related to stunting (low height-for-age) at three years of age in a birth cohort from an urban slum. 相似文献40.
FN Rehman M Audeh ES Abrams PW Hammond M Kenney TC Boles 《Canadian Metallurgical Quarterly》1999,27(2):649-655
A flexible chemistry for solid phase attachment of oligonucleotides is described. Oligonucleotides bearing 5'-terminal acrylamide modifications efficiently co-polymerize with acrylamide monomers to form thermally stable DNA-containing polyacrylamide co-polymers. Co-polymerization attachment is specific for the terminal acrylamide group. Stable probe-containing layers are easily fabricated on supports bearing exposed acrylic groups, including plastic microtiter plates and silanized glass. Attachment can be accomplished using standard polyacrylamide gel recipes and polymerization techniques. Supports having a high surface density of hybridizable oligonucleotide (approximately 200 fmol/mm2) can be produced. 相似文献