Rheology is the science of measuring viscosity, determining the viscoelastic properties, and determining the related functions of rheology and rheometer is an instrument which provides the ability to measure the amount of torque resulting from a controlled deformation and the deformation resulting from a specific controlled torque in steady or periodic states. As a result, it is possible to study fluid properties, determine the relationship between fluid properties and structure and simulate flow behavior under processing conditions. Due to the importance of rheological behavior of materials in various fields from formulation to the application of understanding the basic concepts and familiarity with equipment that can simulate and identify the behavior of materials subject to stress or shear applied at any stage of the manufacturing process is of particular importance. Qouette and capillary viscometers are the most basic equipment used to study rheology, but currently shear rheometers with very wide capabilities are available for quality control and evaluation of product properties. The purpose of this article is to provide an overview of the basic concepts of rheology, to introduce measurement systems and their applications in various industries.

A capillary rheometer was designed and constructed to carry out studies on the flow behaviour of viscous non-Newtonian fluids. Two capillary tubes were attached to the pressure chamber which increase the accuracy of the rheological measurements ( power law index as well as consistency index). By employing two capillary tubes, the power law index can be calculated directly from the measuring values and the accuracy of consistency index increases as well. Capillary tubes with different diameters and various lengths can be used and a wide range of shear rates can be covered by using different tubes. Tests were conducted with solutions of sodium carboxymethyl cellulose (CMC) of different concentrations and various temperatures. The CMC solutions exhibited characteristics typical of power law model of non-Newtonian fluids. The measurements illustrated that the consistency index varies significantly with both concentration and temperature. Increasing concentration enhances consistency index while promoting temperature has a reverse effect. Also concentration has noticeable effect on power law index. As concentration increases the power law index decreases. The effect of temperature on power law index is negligible.

The present study attempted deriving and solving the falling- cylinder governing equations for power law model non-Newtonian fluids. Based on this theoretical study, a novel falling- cylinder rheometer (FCR) was designed and constructed to measure the rheological properties of non-Newtonian fluids. Different falling cylinders with predesigned densities were used to determine the apparent viscosity of polyvinyl alcohol (PVA) solutions in water with various concentrations. The results indicate that all PVA solutions obey the power law model with the power law index as well as the consistency index changing linearly with concentration. Increasing concentration of the solution decreases power law index, while enhances consistency index and apparent viscosity.

Lactation length is different in individual cows, which is generally converted to a 305-day standard using curve fitting models for genetic and management practices. Individual curves do not have a standard shape in all cases, and can deviate from the standard pattern according to factors such as individual differences, and type of fitted models. These non-standard curves, called atypical, resulted from incorrect estimated parameters of the curves; which consist of: continuously increasing or decreasing and reversed standards. This study was conducted to investigate the importance of atypical curves in estimation of 305-day milk production, by fitting two nonlinear models? Wood (empirical) and Pollott (biological), on 7659 and 6692 test-day milk yield of 977 and 776 first calving Iranian Simmental and Jersey cows, during 2007-2020, using R software. Different patterns obtained based on the combination of increasing (b) and decreasing (c) phase parameters of curves. The number of standard curves from the Pollott and Wood models were 85.5% and 62.2% for Simmental, and 83.1% and 70.6% for Jersey cows, respectively. Only continuously increasing curves were observed in both breeds in Pollott model (14.8% and 16.9%, Simmental and Jersey cows, respectively); Whereas in Wood model, all 3 groups of atypical curves were observed, which the reversed standard was the most (22.3% and 16.5%, Simmental and Jersey cows, respectively). Based on the findings, at the time of standardizing the production of dairy cows (national evaluations), not only differences between breeds, but also special attention to the production of atypical curves, should be paid (to correct or discard them).

In this paper simple quartic trigonometric polynomial blending functions, with a tension parameter, are presented. These type of functions are useful for constructing trigonometric Bezier curves and surfaces, they can be applied to construct continuous shape preserving interpolation spline curves with shape parameters. To better visualize objects and graphics a tension parameter is included. In this work we constructed the Trigonometric Bezier curves followed by a construction of the shape preserving interpolation spline curves with local shape parameters and finally several numerical examples are presented such as open shape preserving interpolation curve, closed shape preserving interpolation curve and surfaces. As a direct application we computed the area surrounded by a closed curve.

 The purpose of this study was relationship between spinal curves and specialized movements of Bastanykaran. Study sample included 73 athletes from Bastanykaran 18-36 years Kerman that had at least 2 years experience. Flexible ruler was used for measuring spinal curves. For data analysis of statistical methods at two levels of descriptive and inferential (Chi square ( c2) coefficient of agreement C) through the statistical software SPSS, were used. Results showed that %47.9 of Bastanykaran have hyperkyphosis and %32.9 of this community have hyperlordosis. The findings was significant relationship between movement of Turning the Meel (p<0.05, c2=8.70) and movement of Whirling (p<0.05, c2=9.20) with the amount kyphosis arch, and movement of Kabbadeh Workouts and amount lordosis curve of Bastanykaran (p<0.05, c2=8.64).