Search for dissertations about: "waveform monitoring"

Showing result 1 - 5 of 16 swedish dissertations containing the words waveform monitoring.

2. 1. Fiber-based all-optical sampling for ultrafast waveform monitoring

   Author : Mathias Westlund; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polarization independent; waveform monitoring; software synchronization; four-wave mixing; all-optical sampling;

   Abstract : Digital sampling is a technique to visualize a time-varying waveform by capturing quasi-instantaneous snapshots of a signal via a sampling gate. The gate is opened and closed by narrow pulses in a pulse train having a well defined repetitive behaviour such that all parts of the waveform are measured. READ MORE

4. 2. Fetal ECG waveform analysis for intrapartum monitoring

   Author : Isis Amer-Wåhlin; Lund Obstetrik och gynekologi; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; reproduction; Obstetrics; gynaecology; andrology; cerebral metabolism; microdialysis; implementation; fetal asphyxia; intrpartum monitoring; Fetal ECG; Cardiotocography; sexuality; Obstetrik; gynekologi; andrologi; reproduktion; sexualitet;

   Abstract : Waveform analysis of the fetal electrocardiogram has been studied since the early seventies from both physiological, signal processing and clinical aspects. It has been found to contain more useful information than the mere detection of RR-intervals (fetal heart rate), e.g. READ MORE

5. 3. Quantifying the Seismic Response of Underground Structures via Seismic Full Waveform Inversion : Experiences from Case Studies and Synthetic Benchmarks

   Author : Fengjiao Zhang; Christopher Juhlin; Ari Tryggvason; Yanghua Wang; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; full waveform inversion; waveform tomography; CO2 monitoring; CO2 sequestration; time lapse seismic; Inversion; Geofysik med inriktning mot fasta jordens fysik; Geophysics with specialization in Solid Earth Physics;

   Abstract : Seismic full waveform inversion (waveform tomography) is a method to reconstruct the underground velocity field in high resolution using seismic data. The method was first introduced during the 1980’s and became computationally feasible during the late 1990’s when the method was implemented in the frequency domain. READ MORE

6. 4. Arbitrary Waveform Impedance Spectroscopy for Characterization and Diagnostics of High Voltage Insulation

   Author : Björn Sonerud; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; insulation testing; aging; monitoring; discrete Fourier transforms; Dielectric measurements; dielectric materials;

   Abstract : In high voltage engineering the dielectric response technique is a widely used tool both for characterization of insulation materials and for diagnostics of components such as transformers and cables. Currently available techniques are not capable of measuring on-line which would be advantageous; when characterizing a material and evaluating the effect of different voltage magnitudes, waveforms and temperatures it is desirable to be able to observe the continuous development of the dielectric properties. READ MORE

7. 5. Computer-based detection of cardiac arrhythmias : methods and systems

   Author : Mats-Erik Nygårds; Linköpings universitet; []
   Keywords : Arrhythmia; monitoring; feature extraction; QRS delineation; power spectrum; ventricular fibrillation; MEDICINE; MEDICIN;

   Abstract : The aim of this study was to develop methods and systems which could improve the accuracy or arrhythmia monitoring and analysis of long-term ECGs and eliminate or reduce the need for continuous visual ECG screening. The detection of arrhythmias was based on an automatic classification of heart beats, using waveform features obtained from a basis signals representation. READ MORE