Some near-regular mechanical systems involve global deviations from their corresponding regular system. Despite extensive research on vibration analysis (eigensolution) of regular and local near-regular mechanical systems, the literature on vibration analysis of global near-regular mechanical systems is scant. In this paper, a method for vibration analysis of such systems was developed using Kr...

loading conditions and complex geometry have led the cylinder heads to become the most challenging parts of diesel engines. one of the most important durability problems in diesel engines is due to the cracks valves bridge area. the purpose of this study is a thermo-mechanical analysis of cylinder heads of diesel engines using a two-layer viscoplasticity model. in this article, mechanical prope...

Tolerance analysis of mechanical assemblies is an important tool in reliable design of products at low cost and good quality. Using this tool, it is possible in manufacturing stage to observe the effect of parameters on assembly requirements. The direct linearization method is a useful method which runs based on vector loop analysis. In this research, the DLM method is used to analyze the toler...

In current study, the synthesis and characterization of novel thermally stable polyimides (PIs) containing an 1,3,4-oxadiazole moiety based on a diamine, i.e. 2,5-bis(3-amino-4-methyl benzene)-1,3,4-oxadiazole (BAMO), have been reported. The polymers were characterized using FT-IR and elemental analysis (CHN). Thermal and mechanical behaviours of the prepared PIs were studied by thermo-gravimet...

Tolerance analysis of mechanical assemblies is an important tool in reliable design of products at low cost and good quality. Using this tool, it is possible in manufacturing stage to observe the effect of parameters on assembly requirements. The direct linearization method is a useful method which runs based on vector loop analysis. In this research, the DLM method is used to analyze the toler...

maleic anhydride (man) copolymers with methyl methacrylate(mma), ethyl methacrylate(ema), methyl acrylate(ma), ethyl acrylate (ea) and buthyl acrylate (ba) ( in a 1:1 mole ratio) were synthesized by free radical polymerizations method under vacuum -azobis(isobutironitrile)(aibn) as an initiator of reaction at 701c. the copolymer compositions were determined using related 1h nmr spectra techni...

This paper presents a comprehensive case study on electro-mechanical analysis of MEMS[1] variable capacitors. Using the fundamental mechanical and electrical equations, static and dynamic behaviors of the device are studied. The analysis is done for three different modes, namely: dc (static mode), small signal ac and large signal regime. A complete set of equations defining dynamic behavior of ...

this study focuses on achieving high stiffness/strength and good fr characteristic of nylon 66/mca/nc nanocomposites, prepared via melt compounding by twin screw extruder. a synergistic effect of flame retardant systems based on melamine cyanurate and zinc borate on the flammability and mechanical behaviours of crysnanoclay reinforced nylon 66 nanocomposites have been reported. mechanical test ...