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The part of the stator leakage inductance whose quantity changes with the coil pitch is the slot leakage inductance. The purpose of this paper is to determine an analytical expression which accounts for various slot shapes and the coil pitch change. This approach contrasts with the standard one, in which the same characteristics are inaccurately assumed for each slot shape. A further advantage of the proposed analytical expression is that it can also be used to model the slot leakage inductance for different phase numbers.

From the calculated coefficients of a slot by the Finite Element Method (FEM), the characteristics of the slot leakage coefficients are determined by an analytical expression. This helps one to study the connection between the slot shape types and the characteristics of slot leakage coefficients for different phase numbers.

The coefficients, which describe the change of slot leakage, are not the same for every slot type. These inaccuracies can result in deviation from the presented values in the classical literature.

By use of parameters, gained from the FEM calculation of a slot, the characteristics of the slot leakage coefficient can be determined as the function of winding pitch for different phase numbers by an analytical expression. Good accuracy of the analytical method is verified by the determination of the characteristics from the measurement of the two‐, three‐ and six‐phase windings and by the finite element calculations. Beside the speed of the process, it gives an overview about the connection between the slot shape and the coefficients.

To determine static friction coefficients between rapid tooled materials and thermoplastic materials to better understand ejection force requirements for the injection molding process using rapid‐tooled mold inserts.

Static coefficients of friction were determined for semi‐crystalline high‐density polyethylene (HDPE) and amorphous high‐impact polystyrene (HIPS) against two rapid tooling materials, sintered steel with bronze (LaserForm ST‐100) and stereolithography resin (SL5170), and against P‐20 mold steel. Friction tests, using the ASTM D 1894 standard, were run for all material pairs at room temperature, at typical part ejection temperatures, and at ejection temperatures preceded by processing temperatures. The tests at high temperature were designed to simulate injection molding process conditions.

The friction coefficients for HDPE were similar on P‐20 Steel, LaserForm ST‐100, and SL5170 Resin at all temperature conditions. The HIPS coefficients, however, varied significantly among tooling materials in heated tests. Both polymers showed highest coefficients on SL5170 Resin at all temperature conditions. Friction coefficients were especially high for HIPS on the SL5170 Resin tooling material.

Applications of these findings must consider that elevated temperature tests more closely simulated the injection‐molding environment, but did not exactly duplicate it.

The data obtained from these tests allow for more accurate determination of friction conditions and ejection forces, which can improve future design of injection molds using rapid tooling technologies.

This work provides previously unavailable friction data for two common thermoplastics against two rapid tooling materials and one steel tooling material, and under conditions that more closely simulate the injection‐molding environment.

Drape of the fabric is its ability to hang freely in graceful folds when some area of it is supported over a surface and the rest is unsupported. When two‐dimensional fabrics are converted to three‐dimensional garment forms, a number of operations are required which affect drape behaviour of the fabric while present in garment form. In the present study, the effect of sewing and fusing of interlining on drape behaviour of men's suiting fabrics is investigated.Design/methodology/approach – The effect of sewing and fusing of interlining on drape behaviour of men's suiting fabrics is investigated. Comparisons were also made between different stitches (chain stitch and lock stitch), different seams for lock stitch and different types of interlinings for their effect on drape behaviour of fabrics. In addition to drape coefficient and number of folds, a new drape parameter – average amplitude to average radius (A/r) ratio – was also defined and calculated for drape image geometry.Findings – Drape coefficient has a good to strong correlation with A/r ratio and number of folds for most of the shell, sewn and interlining fused fabrics except for a few cases. A/r defines image in a more descriptive manner than drape coefficient. Drape coefficient changes with the types of seams and stitches used, as well as with the interlining used.Originality/value – This paper provides information on the effects of sewing (seams and stitch types) and fused interlining on drape behaviour of men's suiting fabrics.

The purpose of this paper is to examine empirically the nature of smoothing returns practices in a sample of 79 Islamic banks across 19 countries during the period 2001‐2006.

Previous researchers' methods, based on the variation and determination coefficients, are used in this study to detect the smoothing practices.

Results indicate that the revenues from the “Shariah‐based products” derived from the profit and loss sharing principle show higher variability than the “Shariah compliant revenues” and that income from this source is relatively lower. They also show that a large number of Islamic banks engage in natural income smoothing. Based on the determination coefficient results, 70 per cent of banks were found to have less smoothed total revenue than their net income. Results based on variation coefficient further confirm this finding, with 67 banks having a coefficient of total revenue higher than that of the net income.

The results suggest that Islamic banks should strengthen the use of smoothing techniques, such as the profit equalization reserves (PER) and the investment risk reserves (IRR), as they allow them to further stabilize the revenues payout for the investment account holders (IAH) and therefore mitigate withdrawal risk. Standardizing the smoothing techniques could be a solution to overcome the variability of this category of revenue.

This work is the first of its kind for Islamic banks. It extends previous research by examining whether or not managers may smooth their results naturally or intentionally. It also helped to bridge the gap in the literature by providing the empirical evidence on the smoothing returns in Islamic finance.

It is important to know the friction coefficient and wear loss for determination of tribological conditions at journal bearings. Tribological events that influence wear and its variations affect experimental results. The purpose of this paper is to determine friction coefficient and wear loss at CuSn10 alloy radial bearings by a new approach. In experiments, effects of bearings have been examined at dry and lubricated conditions and at different loads and velocities.

In this study, friction coefficient and wear losses of journal and bearing have been determined by a new approach with a radial journal bearing test rig and artificial neural networks (ANNs) method. The ANN typifies a learning technique that enables the hidden input‐output relationship to be mapped accurately. Bronze‐based materials have been used as bearing material. Effects of friction coefficient and wear losses have been examined at same load and velocity and at dry and lubricated conditions.

The results obtained in ANN application are close to friction test results for dry and lubricated conditions. Therefore, by using trained ANN values, the intermediate results that were not obtained in the tests can be calculated. Experimental studies will be increased and research with ANN will be continued.

By using trained ANN values, the intermediate results that were not obtained in the tests can be calculated. The training finished on 30 min whereas experimental study had continued day after day.

The knowledge of the heat transfer coefficient is important for the proper design of heat exchangers as well as for the determination of the working medium outlet temperatures. This paper aims to present a method of simultaneous determination of coefficients in correlation formulas for the Nusselt number on both sides of the heat transfer surface.

The idea of the developed method is based on determining such a values of the coefficients in Nusselt number correlations that fulfill the condition of equality between the measured and calculated temperature at the outlet of heat exchanger in terms of least squares method. To test the proposed method, a special experimental installation was built. The heat transfer in helically coiled tube-in-tube heat exchanger was examined for the wide range of temperature changes and volumetric flow rates of working fluid.

The simulation results were validated with an experimental data. The results show that the heat transfer coefficient of the counter-current is higher than the co-current flow in helically coiled heat exchanger. This phenomenon can be beneficial particularly in the laminar flow regime.

The correlation for the Nusselt number as a function of the Reynolds and Prandtl numbers for hot and cold liquid was obtained with the least squares method for the experimental data.

The presented method allows for the simultaneous determination of heat transfer coefficient on both sides of the wall without the necessity of indirect calculation of the overall heat transfer coefficient. The presented method can be used in the thermal design of various type heat exchangers.

This work presents the new methodology of determination correlations for the helically coiled tube-in-tube heat exchanger for co-current and counter-current arrangement, which can be used in thermal design.

AT the present time it is a general practice to make extensive investigations of the flutter and oscillatory stability characteristics of all prototype aircraft at an early stage in the design. So far as theoretical investigations of these characteristics are concerned there is often considerable uncertainty as to the values of the aerodynamic coefficients to be used, for there is evidence that measured and theoretical coefficients may differ considerably. Measured values of the coefficients are therefore required both for direct use in calculations and as a check on the theoretical coefficients, and also to provide a guide in the development of more precise theories. Unfortunately the wide variations in wing plan forms and the rapid increase in flight speeds which have occurred in recent years have meant that experimental work in this particular field has not kept pace with development and the designer is faced with the problem of ensuring the safety and operational efficiency of his aircraft using theoretical coefficients whose values may be unreliable.

This paper aims to provide efficient methods to calculate the friction coefficients and film thickness ratios in mixed lubrication (ML) regime for water lubricated bearings. Mathematical models consider influence of micro-asperities contacts which is based on the Gauss random distribution.

Effects of external loads, rotating speeds and radial clearances are obtained. Algorithm shown here is applied to a class of common industrial problems. Calculated Stribeck values are given and evaluated. The calculated and experimental results agree well which proves the correctness of the model.

In Part I, the authors believe that the paper presents the following for the first time: universal methods are developed for the calculation of friction coefficients and film thickness ratios (lambda) in ML regime; effects of different external loads, rotating speeds and radial clearances on friction coefficients and film thickness ratios are presented in detail; comparisons are made between the results predicted by the model and experimental results, and they agree rather well which proves the correctness of the model.

Present work successfully develops universal methods for predicting the friction coefficients and film thickness ratios.

The purpose of this study was to determine correlation between an accelerated cyclic corrosion test (S6‐cycle test) specified in Japanese Industrial Standards K5621 and field exposure tests, and to open up applications of the accelerated tests in various regional environments.

The S6‐cycle corrosion test was carried out on structural steels for 30, 60, 90, 120 and 150 days and metal coating films for 100, 200 and 300 days. Comparing the weight loss of the steels with 1‐, 3‐, 5‐ and 9‐year field exposure test data at 31 sites in Japan. Correlation of the S6‐cycle tests to the field exposure tests was determined by acceleration coefficients.

The correlation between the S6‐cycle test and the field test on uncoated structural steels can be determined by acceleration coefficients based on flying salt amount. The coefficients were applicable for durability prediction of uncoated, zinc hot‐dip galvanized and painted steels.

In determination of the accelerated coefficients, only the flying salt amount was considered. Others factors such as temperature and humidity will be considered in future work.

Using the S6‐cycle corrosion test and its accelerated coefficients, the thickness loss of uncoated structural steels and zinc hot‐dip galvanizing is predictable in a short time. Corrosion degradation of coated steels is also predictable approximately.

This paper contributes to open up the application of accelerated cyclic corrosion test to evaluating corrosion resistance of steel bridge members.

The purpose of this paper is to analyse dynamic drape behaviours of 100% wool woven suiting fabrics considering real-time usage.

Dynamic drape coefficients of 100% wool woven fabrics were measured at different rotation speeds (25, 75, 125 and 175 rpm) with a commercially used fabric drape tester which works on image processing principle. Average daily walking speed of male and female volunteers was determined and the closest rotation speed was selected to calculate dynamic drape coefficient at walking (DDCw). Besides, bending rigidity and shear deformation properties, which are known to be related to the static drape behaviours of the fabrics, were also measured and the relationships between these parameters and DDCw were examined.

As a result of the experimental study, it was found that dynamic drape coefficients become greater, which means the fabrics take flatter position, with the increase of the rotation speed. In addition, it was also seen that parameters known to be related to static drape behaviours such as unit weight and bending stiffness have less effect on the dynamic drapes of fabrics. For the estimation of dynamic drape behaviour of fabrics, parameters such as static perimeter, dynamic perimeter, etc. are found more significant.

To date, although studies about dynamic drape behaviours of the fabrics claimed that dynamic drape gives more realistic results for in wearer experience, few of them focused on the rotation speed of dynamic drape tester for real-time usage. As dynamic drape behaviours of fabrics may differ for different rotation speed, determining appropriate speed in accordance with real-time usage gives more realistic results.