## 1 Introduction
The measured resonance feedback is proportional to fluid density and viscosity that is modified when a change happens in the shear stress of fluid [7; 8; 9; 10]. This method has been successfully employed in industrial real-time detection applications [11; 12] even though some ranges of fluid viscosity--specifically in comparative applications--are not detectable due to the low vibration amplitude of this measurement system ([PERSON], et al., 2005). In biological applications, micromachined quartz resonators have been used as density and viscosity measurement systems [13; 14]. However, the piezoelectric films are not easily integrable during microfabrication [15]. Resonating cantilevers and plates have been the most frequently used type of MEMS viscometers [16; 17; 18] which are usually actuated by means of piezoelectric material [19; 20; 21], magnetic field [22; 23; 24] or alternating electricity current [25; 26; 27]. Theoretical studies and models connect variations in fluid density and viscosity to the shift in resonant frequency and quality factor, respectively [28; 29; 30]. There are not many viscometers designed based on only fluid flow in a microfluidic channel. One example, used for viscometric study of blood, was the integration of two electrodes in a microchannel and monitoring of the changes in fluid impedance [31]. Considering the non-Newtonian effect of fluids,some MEMS-based microplate oscillating systems have been designed and the governing equations were derived [26] as Equation (3),  
\[\text{Vibrating microplate},\ \mu\rho=\frac{2}{\omega}\Big{(}P/aBU_{o}^{2}\Big{)}^{2} \tag{3}\]  
where \(\omega\) is oscillation frequency, \(U_{0}\) is motion amplitude, \(B\) and \(a\) are plate width and length, \(\mu\) is fluid dynamic viscosity, \(\rho\) is fluid density and \(P\) is average oscillation power over a period. As is apparent from the abovementioned formula, Equation (3), frequency change in microsystems submerged in fluid is dependent on both density and viscosity (\(\mu\) and \(\rho\)). In other words, to extract viscosity using these microsystems, a knowledge of fluid density is required. Otherwise, in some articles, another parameter such as quality factor is measured in order to have another equation for the two unknowns. Although these methods are addressing the viscosity measurement, these formulas are mainly useful for Newtonian and single-phase fluids where the viscosity changes can be assumed negligible with respect to shear stress, and density can be measured with other methods. However, in non-Newtonian or multi-phase fluids, both density and viscosity are subject to change at different flow rates. Thus, the fluid has these two parameters, namely, dynamic viscosity and density, interconnected. To study and measure fluid properties, kinematic viscosity captures this interconnectivity of fluid properties at different flow conditions in addition to being measured easily by the proposed platform. Kinematic viscosity measurement is most frequently used in chemical processing and oil industries where fluid is sheared and displaced at the same time. On the other hand, the processing of chemicals such as crude oil is happening during a long process, and in each step a certain fluid with some concentration is being separated/added while the rest goes on to the next processing machine. During each process, it is very difficult to calculate and measure fluid dynamic viscosity or density as the concentration of each parameter should be precisely determined while the process is ongoing quickly. Thus, kinematic viscosity can be used as a single parameter in this industry to qualify the chemical's specifications at a certain processing step. In order to obtain kinematic viscosity from dynamic viscosity, measuring of solution density--which changes with different concentration--is required. Here, to get rid of this density measurement, the fluid specifications can be identified using kinematic viscosity which can be measured as a solution parameter using devices such as capillary viscometers.