4 research outputs found
Bulk Current Injection Testing of Close Proximity Cable Current Return, 1kHz to 1 MHz
This paper presents the results of an experiment examining the percentage of current that returns on adjacent wires or through a surrounding cable shield rather than through a shared conducting chassis. Simulation and measurement data are compared from 1 kHz 1 MHz for seven common cable configurations. The phenomenon is important to understand, because minimizing the return current path is vital in developing systems with low radiated emissions
Reducing Printed Circuit Board Emissions with Low-Noise Design Practices
This paper presents the results of an experiment designed to determine the effectiveness of adopting several low-noise printed circuit board (PCB) design practices. Two boards were designed and fabricated, each consisting of identical mixed signal circuitry. Several important differences were introduced between the board layouts: one board was constructed using recommended low-noise practices and the other constructed without such attention. The emissions from the two boards were then measured and compared, demonstrating an improvement in radiated emissions of up to 22 dB
Comparison of Analysis, Simulation, and Measurement of Wire-to-Wire Crosstalk
In this investigation, we compare crosstalk analysis, simulation, and measurement results for electrically short configurations. Methods include hand calculations, PSPICE simulations, Microstripes transient field solver, and empirical measurement. In total, four representative physical configurations are examined, including a single wire over a ground plane, a twisted pair over a ground plane, generator plus receptor wires inside a cylindrical conduit, and a single receptor wire inside a cylindrical conduit. Part 1 addresses the first two cases, and Part 2 addresses the final two. Agreement between the analysis, simulation, and test data is shown to be very good
Dosimetric differences between intraoperative and postoperative plans using Cs-131 in transrectal ultrasound-guided brachytherapy for prostatic carcinoma.
The aim of the study was to investigate the differences between intraoperative and postoperative dosimetry for transrectal ultrasound-guided transperineal prostate implants using cesium-131 ((131)Cs). Between 2006 and 2010, 166 patients implanted with (131)Cs had both intraoperative and postoperative dosimetry studies. All cases were monotherapy and doses of 115 were prescribed to the prostate. The dosimetric properties (D90, V150, and V100 for the prostate) of the studies were compared. Two conformity indices were also calculated and compared. Finally, the prostate was automatically sectioned into 6 sectors (anterior and posterior sectors at the base, midgland, and apex) and the intraoperative and postoperative dosimetry was compared in each individual sector. Postoperative dosimetry showed statistically significant changes (p \u3c 0.01) in every dosimetric value except V150. In each significant case, the postoperative plans showed lower dose coverage. The conformity indexes also showed a bimodal frequency distribution with the index indicating poorer dose conformity in the postoperative plans. Sector analysis revealed less dose coverage postoperatively in the base and apex sectors with an increase in dose to the posterior midgland sector. Postoperative dosimetry overall and in specific sectors of the prostate differs significantly from intraoperative planning. Care must be taken during the intraoperative planning stage to ensure complete dose coverage of the prostate with the understanding that the final postoperative dosimetry will show less dose coverage