The very-high-frequency components (150-250 Hz) of the electrocardiogram were evaluated. Experiments were designed to determine the extent to which the morphology of the high-frequency QRS potentials is affected by tr...
详细信息
The very-high-frequency components (150-250 Hz) of the electrocardiogram were evaluated. Experiments were designed to determine the extent to which the morphology of the high-frequency QRS potentials is affected by transient myocardial ischemia. The high-frequency ECG was studied in dogs during induced ischemia and in patients undergoing angioplasty. It was found that the high-frequency ECG appears to detect evidence of transient ischemia with greater sensitivity than visual inspection of the surface ECG and may therefore provide useful information. A finite-element three-dimensional model with a self-similar (fractal) conduction system was introduced as a bridge to the understanding of these electrocardiographic phenomena. By using this model it was found that the morphological changes in the high-frequency QRS can be attributed to a slowing of conduction velocity in the region of ischemia.< >
The authors present a real-time technique for detecting the fetal electrocardiogram from abdominal recordings. An averaged maternal waveform is obtained by using a cross-correlation function, which is then subtracted ...
详细信息
The authors present a real-time technique for detecting the fetal electrocardiogram from abdominal recordings. An averaged maternal waveform is obtained by using a cross-correlation function, which is then subtracted from the abdominal signal, resulting in complete elimination of the maternal signal. The fetal heart rate and an averaged fetal ECG (electrocardiogram) is then extracted by using the same averaging process, making it possible to recognize fetal P and T waves. The recording system is based on an IBM AT compatible personal computer with an 80286 processor and 80287 coprocessor. Since computer performances were not sufficient to give real-time outputs, a fast correlator board was developed which works in parallel with the computer and is able to enhance the computer throughput. The system is simple, and no special training is required.< >
The design of passenger vehicles for improved aerodynamic characteristics will result in reduced fuel consumption and better road handling during high-speed driving. In this research, techniques were developed to meas...
详细信息
Learning leads to a decrease in program cost and inflation leads to an increase in program cost. At a certain time, the benefits of leaming and the penalty due to inflation will balance each other. This time is define...
暂无评论