Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1038/scientificamerican0719-21 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Terahertz (THz) generation via photomixing on photoconductive antenna using twin delayed chirped pulses provides a long THz pulse with a narrow bandwidth. To generate a long pulse with a broad bandwidth, we propose a new, to the best of our knowledge, method that combines two long optical pulses with opposite chirps. The pulses exhibit temporal distributions of their instantaneous frequencies with opposite slopes.
View Article and Find Full Text PDFA new sensor-less voltage and frequency control of stand-alone DFIG based dead-beat direct-rotor flux control-experimental validation.
ISA Trans
December 2024
Electrical Engineering Department, Faculty of Engineering, Minia University, Minia 61111, Egypt. Electronic address:
The paper presents a new sensor-less voltage and frequency control method for a stand-alone doubly-fed induction generator (DFIG) feeding an isolated load. The proposed control approach directly regulates the magnitude and angle of the rotor-flux vector rather than controlling rotor currents or voltages as in classic field oriented control (FOC). To accurately regulate the magnitude and frequency of stator voltage, two separate closed-loop based PI regulators are employed to evaluate the reference signals of the rotor flux vector magnitude and angle, respectively.
View Article and Find Full Text PDFProactive esophageal cooling during radiofrequency cardiac ablation: data update including applications in very high-power short duration ablation.
Expert Rev Med Devices
January 2025
Cardiac Electrophysiology, NorthShore University Health System, Evanston, IL, USA.
Introduction: Proactive esophageal cooling reduces injury during radiofrequency (RF) ablation of the left atrium (LA) for the treatment of atrial fibrillation (AF). New catheters are capable of higher wattage settings up to 90 W (very high-power short duration, vHPSD) for 4 s. Varying power and duration, however, does not eliminate the risk of thermal injury.
View Article and Find Full Text PDFComparative analysis of heart rate variability indices from ballistocardiogram and electrocardiogram: a study on measurement agreement.
Heart Vessels
December 2024
Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
Ballistocardiogram (BCG) captures minute vibrations generated by heart movements. These vibrations are converted into heart rate variability (HRV) indices, allowing their unobtrusive monitoring over extended periods, while reducing the burden on patients or subjects. In this study, to evaluate the agreement between the HRV indices, we compared the HRV indices estimated from the BCG device with those obtained from the gold standard electrocardiogram (ECG).
View Article and Find Full Text PDFAssessment of isokinetic trunk muscle parameters, postural control and quality of life in sedentary and active older adults.
J Bodyw Mov Ther
March 2025
Centro de Educação Física e Desportos, Universidade Federal do Espírito Santo, Vitória, Espírito Santo, Brazil. Electronic address:
Objective: The study intended to evaluate the differences between active and sedentary postural control and isokinetic trunk strength. The secondary aim was to evaluate the participants' total physical activity (PA) score regarding the specific quality of life domains assessed.
Methods: An analytical cross-sectional study involving 64 participants of both sexes aged ≥60 years (60-86 years) was conducted.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!