In a single-degree-of-freedom weakly nonlinear oscillator subjected to periodic external excitation, a small-amplitude excitation may produce a relatively large-amplitude response under primary resonance conditions. Jump and hysteresis phenomena that result from saddle-node bifurcations may occur in the steady-state response of the forced nonlinear oscillator. A simple mass-spring-damper vibrat...

The influence of recycling on double-pass solar air collectors with welding of the V-corrugated absorber has been studied experimentally and theoretically. Welding the V-corrugated absorber and the recycle-effect concept to the solar air collector was proposed to strengthen the convective heat-transfer coefficient due to turbulence promotion. Both the recycle effect and the V-corrugated absorbe...

The possibility of suppressing self-excited vibrations of mechanical systems using parametric excitation is discussed. We consider a two-mass system of which the main mass is excited by a ow-induced, self excited force. A single mass which acts as a dynamic absorber is attached to the main mass and, by varying the stiiness between the main mass and the absorber mass, represents a parametric exc...

The Compact Linear Fresnel Reflector (CLFR) is a linear-concentrating solar thermal energy system currently in the prototype stage at the Liddell power station in the Hunter Valley, NSW. A system-level thermo-fluidic model for the CLFR has been developed in order to predict steady-state operating conditions, required pumping power and pressure, mass transfer around the system and likely startup...

We present a new type of transition-edge sensor for single-photon and macro-molecule detection. In our detector the absorber element is an isolated, passive absorber of extremely low thermal mass, maintained close to, but below, its superconducting–normal transition, and strongly inductively coupled to a SQUID sensor. Incoming particles or photons are sensed in terms of a transient change in th...

Abstract: Passive vibration control solutions are often limited to working reliably at one design point. Especially applied to lightweight structures, which tend to have unwanted vibration, active vibration control approaches can outperform passive solutions. To generate dynamic forces in a narrow frequency band, passive single-degree-of-freedom oscillators are frequently used as vibration abso...

This paper presents a reduce roll vibration of the full vehicle model with passive suspension systems using vibration absorber to change the dynamic system matrix stat’s eigenvalue. Since using the controller system has been splurged and required to energy consuming, in this research the vehicle body roll vibration has been reduced and supplied vehicle stability using a vibration absorber for t...

The nonlinear two-degree-of-freedom system under consideration consists of the linear oscillator with a relatively big mass, which is an approximation of some continuous elastic system, and of the vibro-impact oscillator with a relatively small mass, which is an absorber of the linear system vibrations. Analysis of nonlinear normal vibration modes shows that a stable localized vibration mode, w...

We report a deep search for 21 cm emission/absorption from the z ∼ 0.101 candidate damped Lyman-α system towards PKS 0439−433, using the Australia Telescope Compact Array (ATCA). The spectrum shows a weak absorption feature — at the 3.3σ level — which yields a lower limit of 730 K on the spin temperature of the system. No H i emission was detected: the 3σ upper limit on the H i mass of the abso...