Compression of recorded ECG data has been a topic of interest since the introduction of computer storage and later Holter monitor applications of ECG recording technology. Compression is typically performed using an approximation algorithm belonging to one of three classes; direct data compression; transformation and parameter extraction. Some debate exists as to how the accuracy of each implem...

Within the field on biomedical engineering, the majority of compression research has focused on encoding medical images, electrocardiograms, and electroencephalograms. Although long-term myoelectric signal (MES) acquisition is important for neuro-muscular system analysis and telemedicine applications, very few studies have been published on MES compression. This research investigates static and...

Compression is a reduction of the dynamic range of a signal, meaning that the ratio of the loudest to the softest levels of a signal is reduced. This is accomplished using an amplifier with variable gain that can be controlled by the amplitude of the input signal: when the input exceeds a preset threshold level, the gain is reduced. The figure below is a device input/output graph that shows the...

Fusionless devices are currently designed to treat spinal deformities such as scoliosis by the application of a controlled mechanical loading. Growth modulation by dynamic compression was shown to preserve soft tissues. The objective of this in vivo study was to characterize the effect of static vs. dynamic loading on the bone formed during growth modulation. Controlled compression was applied ...

dynamic recrystallization, drx, behaviour of a precipitation hardened, ph, stainless steel was studied in connection with microstructural developments in a compression test. the experimental results showed that the dominant mechanism of softening is drx, but at high strain rates and low temperatures, ie, high zener-holman parameter, z, work hardening and dynamic recovery, drv, produced a pancke...

Biological tissues have the remarkable ability to remodel and repair in response to disease, injury and mechanical stresses. Synthetic materials lack the complexity of biological tissues, and man-made materials that respond to external stresses through a permanent increase in stiffness are uncommon. Here we report that polydomain nematic liquid crystal elastomers increase in stiffness by up to ...

Dynamic range compression, despite being one of the most widely used audio effects, is still poorly understood, and there is little formal knowledge and analysis of compressor design techniques. In this tutorial we describe several different approaches to digital dynamic range compressor design. Digital implementations of several classic analog approaches are given, as well as designs from rece...