A typical passive mechanical isolation system utilizes a mass-spring-damper as a mechanical filter. Active isolation control systems typically include an electromagnetic transducer to develop the required control forces. In this paper, the technique of sensor-less active shunt control is applied to a mechanical isolation system. An electrical impedance is designed and connected to an electromag...

Mitral valvular regurgitation consistently modified the wave form of the first derivative of the transthoracic impedance cardiogram. The transthoracic impedance cardiogram was recorded in 23 control subjects (group 1), and 23 patients with isolated mitral regurgitation (group 2). Simultaneous transthoracic impedance cardiogram, electrocardiogram, and mitral valve echocardiograms in group 1 show...

Some active impedance control experiments in an anechoic chamber are reported. Further active methods are developed for the design of locally controlled absorption liners in air, whose basic principles were described by Olson and May and subsequently investigated practically by Guicking and his colleagues at the beginning of the 80’s. Two methods are described and tested. In the first, processi...

In impedance control for force tracking, it is well known that the reference trajectory of the robot is calculated from known environmental stiffness. The authors present a simple technique for determining the reference trajectory under the condition that the environment is unknown. The technique is developed based on the replacement of the unknown stiffness with a function of the measured forc...

Every unimpaired person in the world walks thousands of steps every day, and has an individual gait pattern, e.g. different velocities, load conditions, surrounding/ground conditions. Unfortunately, the number of lower-limb amputees has been increasing during the last centuries and millions of people are currently affected by amputation. To restore human walking abilities, an active knee prosth...

background: hamadan province is one of the high-risk regions in iran for multiple sclerosis (ms). a majority of the epidemiological studies conducted in iran addressing ms are descriptive. this study was conducted to assess ms and its associated risk factors in hamadan province, the west of iran . methods: this case-control study compared 100 patients with ms (case group) and 100 patients with ...

In this paper, the general problem of impedance control for a robotic manipulator with a moving flexible base is addressed. Impedance control imposes a relation between force and displacement at the contact point with the environment. The concept of impedance control of flexible base mobile manipulator is rather new and is being considered for first time using singular perturbation and new slid...

This paper presents a dynamic range boosting technique for wireless optical receivers. This technique changes the feedback impedance of the transimpedance amplifier by the control of multiple parallel transistors in the triode region. This strategy results on a wide controllable gain amplifier, without extra signalto-noise ratio penalties. A front-end with 20MHz bandwidth, maximum transimpedanc...