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The Journal of the Acoustical Society... Apr 2021The widespread use of ultrasound techniques throughout industry causes many workers to be exposed to airborne ultrasound at their workplaces. To measure and assess the...
The widespread use of ultrasound techniques throughout industry causes many workers to be exposed to airborne ultrasound at their workplaces. To measure and assess the exposure to airborne ultrasound at these workplaces, devices are required that allow reliable measurements of ultrasound levels and support occupational safety and health measures. However, the sound level meters available to date do not meet these requirements. Therefore, a research prototype of a sound level meter covering audible and ultrasonic frequencies was developed, paying particular attention to the suitability of the components in terms of their acoustical characteristics (such as directional patterns) in the ultrasonic frequency range. The prototype was tested based on the international standard for sound level meters IEC 61672-1, with extensions regarding the signal frequencies used. The results revealed that the sound level meter developed is suitable for application at most workplaces exposed to ultrasound, as reflected by, e.g., its frequency range (at least up to 47 kHz), upper level limits (up to 160 dB SPL), and measurement uncertainty (k = 2, GUM) of 1.15 dB. The prototype developed allows measurement and assessment of exposure at workplaces for occupational safety and health purposes. Moreover, it can serve as a basis for future developments of commercial ultrasound level meters.
Topics: Humans; Noise, Occupational; Occupational Exposure; Occupational Health; Sound; Ultrasonography; Workplace
PubMed: 33940896
DOI: 10.1121/10.0004787 -
Psychological Research Mar 2013We examined the influence of incidental exposure to varied metrical patterns from different musical cultures on the perception of complex metrical structures from an... (Comparative Study)
Comparative Study
We examined the influence of incidental exposure to varied metrical patterns from different musical cultures on the perception of complex metrical structures from an unfamiliar musical culture. Adults who were familiar with Western music only (i.e., simple meters) and those who also had limited familiarity with non-Western music were tested on their perception of metrical organization in unfamiliar (Turkish) music with simple and complex meters. Adults who were familiar with Western music detected meter-violating changes in Turkish music with simple meter but not in Turkish music with complex meter. Adults with some exposure to non-Western music that was unmetered or metrically complex detected meter-violating changes in Turkish music with both simple and complex meters, but they performed better on patterns with a simple meter. The implication is that familiarity with varied metrical structures, including those with a non-isochronous tactus, enhances sensitivity to the metrical organization of unfamiliar music.
Topics: Adult; Auditory Perception; Cross-Cultural Comparison; Female; Humans; Male; Music; Recognition, Psychology; Young Adult
PubMed: 22367155
DOI: 10.1007/s00426-012-0427-y -
Expert Opinion on Drug Delivery Jun 2015Deepening the current understanding of the factors governing the performance of the pressurized metered dose inhaler (pMDI) has the potential to benefit patients by... (Review)
Review
INTRODUCTION
Deepening the current understanding of the factors governing the performance of the pressurized metered dose inhaler (pMDI) has the potential to benefit patients by providing improved drugs for current indications as well as by enabling new areas of therapy. Although a great deal of work has been conducted to this end, our knowledge of the physical mechanisms that drive pMDI performance remains incomplete.
AREAS COVERED
This review focuses on research into the influence of device and formulation variables on pMDI performance metrics. Literature in the areas of dose metering, atomization and aerosol evolution and deposition is covered, with an emphasis on studies of a more fundamental nature. Simple models which may be of use to those developing pMDI products are summarized.
EXPERT OPINION
Although researchers have had good success utilizing an empirically developed knowledge base to predict pMDI performance, such knowledge may not be applicable when pursuing innovations in device or formulation technology. Developing a better understanding of the underlying mechanisms is a worthwhile investment for those working to enable the next generation of pMDI products.
Topics: Administration, Inhalation; Aerosols; Chemistry, Pharmaceutical; Humans; Metered Dose Inhalers; Nebulizers and Vaporizers; Pressure
PubMed: 25496601
DOI: 10.1517/17425247.2015.984683 -
Ground Water 2015Water exchange between surface water and groundwater can modulate or generate ecologically important fluxes of solutes across the sediment-water interface. Seepage...
Water exchange between surface water and groundwater can modulate or generate ecologically important fluxes of solutes across the sediment-water interface. Seepage meters can directly measure fluid flux, but mechanical resistance and surface water dynamics may lead to inaccurate measurements. Tank experiments were conducted to determine effects of mechanical resistance on measurement efficiency and occurrence of directional asymmetry that could lead to erroneous net flux measurements. Seepage meter efficiency was high (average of 93%) and consistent for inflow and outflow under steady flow conditions. Wave effects on seepage meter measurements were investigated in a wave flume. Seepage meter net flux measurements averaged 0.08 cm/h-greater than the expected net-zero flux, but significantly less than theoretical wave-driven unidirectional discharge or recharge. Calculations of unidirectional flux from pressure measurements (Darcy flux) and theory matched well for a ratio of wave length to water depth less than 5, but not when this ratio was greater. Both were higher than seepage meter measurements of unidirectional flux made with one-way valves. Discharge averaged 23% greater than recharge in both seepage meter measurements and Darcy calculations of unidirectional flux. Removal of the collection bag reduced this net discharge. The presence of a seepage meter reduced the amplitude of pressure signals at the bed and resulted in a nearly uniform pressure distribution beneath the seepage meter. These results show that seepage meters may provide accurate measurements of both discharge and recharge under steady flow conditions and illustrate the potential measurement errors associated with dynamic wave environments.
Topics: Environmental Monitoring; Groundwater; Lakes; Mechanical Phenomena; Oceans and Seas; Water Movements
PubMed: 25406673
DOI: 10.1111/gwat.12302 -
Ultrasonics Jan 2018Several technologies can be used in ultrasonic gas flow-meters, such as transit-time, Doppler, cross-correlation and etc. In applications, the approach based on...
Several technologies can be used in ultrasonic gas flow-meters, such as transit-time, Doppler, cross-correlation and etc. In applications, the approach based on measuring transit-time has demonstrated its advantages and become more popular. Among those techniques which can be applied to determine time-of-flight (TOF) of ultrasonic waves, including threshold detection, cross correlation algorithm and other digital signal processing algorithms, cross correlation algorithm has more advantages when the received ultrasonic signal is severely disturbed by the noise. However, the reference wave for cross correlation computation has great influence on the precise measurement of TOF. In the applications of the multipath flow-meters, selection of the reference wave becomes even more complicated. Based on the analysis of the impact factors that will introduce noise and waveform distortion of ultrasonic waves, an averaging method is proposed to determine the reference wave in this paper. In the multipath ultrasonic gas flow-meter, the analysis of each path of ultrasound needs its own reference wave. In case study, a six-path ultrasonic gas flow-meter has been designed and tested with air flow through the pipeline. The results demonstrate that the flow rate accuracy and the repeatability of the TOF are significantly improved by using averaging reference wave, compared with that using random reference wave.
PubMed: 28818772
DOI: 10.1016/j.ultras.2017.07.010 -
Clinical Toxicology (Philadelphia, Pa.) Nov 2020Point-of-care glucose meters are an integral part in the assessment of patients with altered mental status. For this reason, glucose meters are checked for interference...
Point-of-care glucose meters are an integral part in the assessment of patients with altered mental status. For this reason, glucose meters are checked for interference from commonly encountered substances, including acetaminophen. The Nova StatStrip glucose meter has previously been reported to be resistant to interference. We report a case of a very high acetaminophen concentration causing interference with this point-of-care glucose meter. A 25-year-old female presented after an overdose of acetaminophen and diphenhydramine combination product. Patient was minimally responsive, so a point-of-care glucose check was attempted using the Nova StatStrip glucose meter. Five different meters were attempted, and each showed an error message. Laboratory analysis using Beckman Coulter Unicel DxC 800 revealed a glucose of 180 mg/dL and an acetaminophen concentration of 465 mg/L. Serum spiked with acetaminophen at different concentrations revealed interference with the Nova StatStrip glucose meter at a concentration of 399 mg/L and above. To our knowledge, this interference with the Nova StatStrip glucose meter has not been reported in the medical literature. Very high levels of acetaminophen can interfere with point-of-care glucose meters, even those that have previously been reported to be robust such as the Nova StatStrip glucose meter. Clinicians should be aware of this possible interference when treating patients with acetaminophen overdose.
Topics: Acetaminophen; Adult; Blood Glucose; Drug Overdose; Female; Humans; Point-of-Care Systems; Reagent Strips
PubMed: 32141341
DOI: 10.1080/15563650.2020.1732404 -
Environmental Science and Pollution... Jan 2024With the increasing integration of renewable energy sources and nonlinear loads in the grid, it is necessary to compute energy and power quality parameters for...
With the increasing integration of renewable energy sources and nonlinear loads in the grid, it is necessary to compute energy and power quality parameters for monitoring as well as analyzing the power consumption indices (PCI) and power quality indices (PQI). Smart meters (SMs) can monitor the PCI and PQI at the consumer end. SM necessitates the measurement of voltage and current, which can be further processed by an algorithm for estimating different parameters through signal processing and arithmetic operations. This paper proposes the combined dual second-order generalized integrator (SOGI) and proportionate least mean square (PLMS) algorithm-based PCI and PQI estimation for smart metering. Dual SOGIs individually process voltage and current signals to extract the respective fundamental in-phase and quadrature components. To account the variations in grid frequency, the SOGI processing the voltage also incorporates a frequency locked loop. This prevents performance degradation on account of frequency variations. The PLMS algorithm then process the output of SOGI processing the current for extracting the fundamental active and reactive components of current. Moreover, the PLMS algorithm results in further attenuation of harmonics. Also, only two separate values of learning rate are required, which is easy to tune for better dynamic performance. With only two quantities to be determined, this results in largely reduced computation. These computations facilitate in PCI and PQI computations. The proposed smart meter calculates peak value, RMS value, and phase angle for the fundamental components of voltage and current for each phase. Additionally, it assesses fundamental power factor, total harmonic distortion (THD), distortion factor, true power factor, active power, reactive power, and apparent power for each phase. The performance validation of the proposed combined dual-SOGI-PLMS algorithm-based PCI and PQI estimation for smart metering is carried out in MATLAB/SIMULINK for fifteen different operating scenarios. Further, the real-time implementation of the proposed methodology is carried out on dSPACE MicroLab Box 1202. Comparative analysis is also presented, which reveals the computational simplicity and other merits of the proposed scheme over the earlier reported scheme.
PubMed: 38180662
DOI: 10.1007/s11356-023-31656-5 -
Environmental Research Apr 2020This paper describes radiofrequency (RF) electromagnetic field (EMF) measurements in the vicinity of single and banks of advanced metering infrastructure (AMI) smart...
This paper describes radiofrequency (RF) electromagnetic field (EMF) measurements in the vicinity of single and banks of advanced metering infrastructure (AMI) smart meters. The measurements were performed in a meter testing and distribution facility as well as in-situ at five urban locations. The measurements consisted of gauging the RF environment at the place of assessment, evaluating the worst-case electric-field levels at various positions around the assessed AMI meter configuration (spatial assessment), which ranged from a single meter to a bank of 81 m, and calculating the duty cycle of the system, i.e. the fraction of time that the AMI meters were actually transmitting (12-h temporal assessment). Both in-situ and in the meter facility, the maximum field levels at 0.3 m from the meter configurations were 10-13 V/m for a single meter and 18-38 V/m for meter banks with 20-81 m. Furthermore, 6-min average duty cycles of 0.01% (1 m) up to 13% (81-m bank) were observed. Next, two general statistical models (one for a single meter and one for a meter bank) were constructed to predict the electric-field strength as a function of distance to any configuration of the assessed AMI meters. For all scenarios, the measured exposure levels (at a minimum distance of 0.3 m) were well below the maximum permissible exposure limits issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP), the U.S. Federal Communications Commission (FCC), and the Institute of Electrical and Electronics Engineers (IEEE). Indeed, the worst-case time-average exposure level at a distance of 0.3 m from an AMI installation was 5.39% of the FCC/IEEE and 9.43% of the ICNIRP reference levels.
Topics: Electricity; Electromagnetic Fields; Environmental Exposure; Environmental Monitoring; Models, Statistical; Radiation, Ionizing; Radio Waves
PubMed: 32032814
DOI: 10.1016/j.envres.2020.109196 -
Optics Express Oct 2016The video streaming, data transmission, and remote control in underwater call for high speed (Gbps) communication link with a long channel length (~10 meters). We...
The video streaming, data transmission, and remote control in underwater call for high speed (Gbps) communication link with a long channel length (~10 meters). We present a compact and low power consumption underwater wireless optical communication (UWOC) system utilizing a 450-nm laser diode (LD) and a Si avalanche photodetector. With the LD operating at a driving current of 80 mA with an optical power of 51.3 mW, we demonstrated a high-speed UWOC link offering a data rate up to 2 Gbps over a 12-meter-long, and 1.5 Gbps over a record 20-meter-long underwater channel. The measured bit-error rate (BER) are 2.8 × 10, and 3.0 × 10, respectively, which pass well the forward error correction (FEC) criterion.
PubMed: 27828488
DOI: 10.1364/OE.24.025502 -
Journal of Diabetes Science and... May 2019Hematocrit is known to influence glucose values obtained on some blood glucose meters, with bias observed especially at low and high hematocrit levels. We evaluated the... (Comparative Study)
Comparative Study
Comparative Accuracy Evaluation of a Blood Glucose Meter With Novel Hematocrit Correction Technology, With Three Currently Used Commercially Available Blood Glucose Monitoring Systems.
Hematocrit is known to influence glucose values obtained on some blood glucose meters, with bias observed especially at low and high hematocrit levels. We evaluated the performance of a meter with hematocrit correction technology alongside 3 other commercially available meters. Capillary blood samples from 100 subjects were analyzed in duplicate and compared to the plasma values obtained by reference laboratory analyzer. Bias, error grid, and sensitivity to hematocrit analyses were performed for each meter. Average percentage bias was similar for all meters, however the evaluated meter performed best with respect to error grid analysis, with 100% of values falling within the "no effect on clinical action" and "no risk" categories and did not display any hematocrit associated bias.
Topics: Artifacts; Blood Glucose; Blood Glucose Self-Monitoring; Commerce; Diabetes Mellitus; Hematocrit; Humans; Reference Standards; Reproducibility of Results; Research Design; Sensitivity and Specificity; United Kingdom
PubMed: 30623673
DOI: 10.1177/1932296818821389