Vibrations are generally recognized as the biggest concern in maintaining part' longevity of an All-in-one PC. The vibrations in PCs originate from excitation sources such as the HDD and the cooling fan. In this study, the vibrations from these sources were investigated in order to analyze the individual effects of the parameters on the structural vibrations of the PC; further, we attempted to establish design alterations that could successfully suppress vibrations, in order to achieve improved stability and part' longevity. The results show that relatively simple design alterations can substantially improve the stability of PCs.

To understand how the input impedance determined at the throat correlates with changes in the dynamic characteristics of the airways, a simplified 5-lobe model is developed and simulated. The model takes into account some realistic conditions such as varying cross-sectional areas, flexible wall properties and branching. The lobe terminal impedances are implemented in the model to predict the input impedance at the throat. The effects of airway constrictions and wall elastance variations on this impedance are determined for a range of frequencies. It is concluded that the developed model is capable of predicting various physiological changes in the airway passages.

In modern industries, in whichwhere high productivity is one of the most important concerns, machine tools are facing difficulties to satisfy the high high-speed operation, while and at the same time achieve the precision machining. Generally, the vibrations of the structure increase proportionally to the square of the operating speed so that the precision machining is severely damaged with increased speed. which is a must for the high productivity. Therefore, the suppression of the structural vibrations of the machine tools is the a major concern in the machine tool industry in order to achieve the high productivity and the precision machining simultaneously. In this study, the dynamic properties of a machining center structure were analyzed through the experiment and the computer simulations, and furthermore the results from those were compared to confirm the validity of the simulation model. The design alterations were deduced from the analysis and applied to the simulation model to investigate the effects of those alterations to suppress the vibrations of the machine. The result shows that the relatively simple design alterations, without redesigning the main structure of the machine, can suppress the vibrations effectively.

No abstract

To understand how the input impedance determined at the throat correlates with changes in the dynamic characteristics of the airways, a simplified 5-lobe model is developed and simulated. The model takes into account some realistic conditions such as varying cross-sectional areas, flexible wall properties and branching. The lobe terminal impedances are implemented in the model to predict the input impedance at the throat. The effects of airway constrictions and wall eleatance variations on this impedance are determined for a range of frequencies. It is concluded that the developed model is capable of predicting various physiological changes in the airway passages.