In this research, a shear-mode MR damper that can replace conventional passive damper of a front-loaded washing machine is designed, manufactured and an experiment based model is employed to characterize hysteresis behavior of the damper. Firstly, an optimized MR damper for front loaded washing machine is manufactured and an experimental system is set up for testing hysteresis behaviour of the damper. The experimental test is then conducted and presented. From experiential results, hysteresis of the damper is investigated and a suitable hysteresis model is proposed for the damper. The proposed hysteresis model of damper is then evaluated through experimental results.

Machining in a heated environment has been used in pressure machining and metal cutting. Thermal-assisted machining is a new machining method performed on conventional machine tools, CNC machines, in which the workpiece is heated before machining. Different heat sources do the thermal-assisted: electrical energy, laser beam, magnetic induction. However, there is very little research on thermal-assisted machining when milling SKD11 steel, a difficult-in-processing material but widely used in the industry. Material machinability refers to the ability of material machining that is difficult or easy. Material machinability is measured by tool life, material removal ability, shear force, cutting vibration, surface roughness. The material's machinability is directly influenced by its microscopic structure and is related to the cutting mode. This paper has highlighted the study of material machinability when thermal-assisted machining and compared to the conventional one. This study also highlights the crucial role in assessing the effect of heating on the SKD11 steel machinability. This study analyzed the technological parameters' role on the shear force, chip shrinkage, surface roughness, and shear vibrations during normal machining and SKD11 steel heating. The study results showed that the material's microstructure and the amplitude of vibration did not change under the heating process's effect with a temperature range of 200 o C -400 o C. However, the shearing force during heat processing is drastically reduced compared to conventional machining. Chip shrinkage increased by 31.7% when heated to 400 o C, while roughness decreased by 47.1%.

Since the early years of the 21st century, the whole world has faced two very urgent problems: the depletion of fossil energy sources and climate change due to environmental pollution. Among the solutions sought, 2,5-Dimethylfuran (DMF) emerged as a promising solution. DMF is a 2nd generation biofuel capable of mass production from biomass. There have been many studies confirming that DMF is a potential alternative fuel for traditional fuels (gasoline and diesel) in internal combustion engines, contributing to solving the problem of energy security and environmental pollution. However, in order to apply DMF in practice, more comprehensive studies are needed. Not out of the above trend, this paper analyzes and discusses in detail the characteristics of DMF's combustible laminar flame and its instability under different initial conditions. The evaluation results show that the flame characteristics of DMF are similar to those of gasoline, although the burning rate of DMF is much higher than that of gasoline. This shows that DMF can become a potential alternative fuel in internal combustion engines.

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Cutting force is a vital parameter that affects product quality. Proper control of the cutting force helps optimize the production process as it improves productivity and product quality. This paper assesses the influence of machining parameters, such as alloy steel hardness and workpiece diameters, to cutting forces when external cylindrical grinding by experimental methods. The cutting force was measured using a workpiece shaft-mounted sensor with a balanced bridge-type resistor sensor. Steel for testing: 40Cr, 9CrSi, 65Mn, and W18Cr4V, which were heat-treated at three different hardness levels: 40, 50, and 60 HRC. The Taguchi method's experimental results show that the main parameters affecting cutting forces are: Feed rate of the grinding wheel Sd, cutting depth t, and hardness of workpiece material on the HRC scale. Since then, we built a mathematical model of the normal cutting force function Fn and tangent cutting force function Ft according to Sd, t, and HRC of 9CrSi steel then tested again with three steel types: 40Cr, 65Mn, and W18Cr4V for quite similar results. The cutting force is controlled through cutting parameters suitable for different hardness and workpiece material based on this model.