Flowchart-aided design of a novel spatial flapping wing mechanism

The flapping wing mechanism is an important member in flapping wing micro air vehicles. In this paper, a novel flapping wing mechanism and a framework to facilitate its design are introduced. High degree of symmetry and being free from sliders are two important features of this mechanism. The mentioned design framework consists of three algorithms for dimensional synthesis and one algorithm for mechanical design, which are presented in four flowcharts. In order to achieve the dimensional synthesis flowcharts, a parametric dimensional synthesis is performed, which includes examining the effects of different parameters on the important variables of design. The flowchart of mechanical design facilitates determining the optimized thicknesses of the mechanism members. The force analysis of the mechanism, as a part of mechanical design algorithm, is conducted using a MATLAB code based on the D'Alembert and superposition principles. An example of designing the mechanism using the introduced algorithms, a manufactured sample of the mechanism, and some alternative structures for the mechanism are presented in the final sections of the paper.

New non-conventional methods for quantitative concepts of anomalous rheology

This paper addresses the general calculus operators with respect to another functions containg the power-law and exponential functions. The Boltzmann-type superposition principles for the anomalous linear viscoelasticity are considered for the first time. The new technologies are as non-conventional tools proposed to extend the quantitative concepts of anomalous rheology for solid mechanics.

Superposition of survival curves as a tool for epistasis analysis of longevity interventions

A long-standing problem in ageing research is to understand how different factors contributing to longevity should be expected to act in combination under the assumption that they are independent. Standard epistasis analysis compares the extension of mean lifespan achieved by a combination of interventions to the prediction under an additive or multiplicative null model, but neither model is fundamentally justified. Moreover, the target of longevity interventions is not mean life span but the entire survival curve. Here we formulate superposition principles that predict the survival curve resulting from a combination of two interventions based on the survival curves of the individual treatments, and quantify epistasis as the deviation from this prediction. We test the method on a published data set comprising survival curves for all combinations of 4 different longevity interventions in Caenorhabditis elegans. We find that epistasis is generally weak even when the standard analysis indicates otherwise.

Active Control of Pressure Pulsation in a Piping System Using Measured Dynamic Flow Rate

Fluid-borne noise is caused primarily by unsteady flow from pumps and motors and the instability and cavitation of valves. It takes the form of pressure pulsation or fluctuations in the fluid, and results in structure-borne noise and air-borne noise. An effective method to reduce the noise is needed that does not impair the system performance. In this paper, an active attenuator of pressure pulsation in a conventional piping system is proposed. The unsteady flowrate is determined indirectly by using easily-measured pressure signals and implemented in a controller which is designed based on wave propagation and superposition principles. Simulated and experimental results on a test rig show a good attenuation. It is concluded that a well-designed noise attenuator could potentially provide significant reduction in pressure pulsation in a piping system.

A Class of PDEs with Nonlinear Superposition Principles

Through assuming that nonlinear superposition principles (NLSPs) are embedded in a Lie group, a class of 3rd-order PDEs is derived from a general determining equation that determine the invariant group. The corresponding NLSPs and transformation to linearize the nonlinear PDE are found, hence the governing PDE is provedC-integrable. In the end, some applications of the PDEs are explained, which shows that the result has very subtle relations with linearization of partial differential equation.