scholarly journals Performance Evaluation of Honeywell Silicon Piezoresistive Pressure Transducers for Oceanographic and Limnological Measurements*

2005 ◽  
Vol 22 (12) ◽  
pp. 1933-1939 ◽  
Author(s):  
Vijay Kumar ◽  
Antony Joseph ◽  
R. G. Prabhudesai ◽  
S. Prabhudesai ◽  
Surekha Nagvekar ◽  
...  
Keyword(s):  
Temperature Sensitivity ◽  
Pressure Range ◽  
Effective Means ◽  
Pressure Sensors ◽  
Zero Point ◽  
Full Scale ◽  
Absolute Pressure ◽  
Pressure Transducers ◽  
Temperature Range ◽  
The Mean

Abstract Simultaneous calibrations of three temperature-compensated piezoresistive ruggedized precision “absolute” pressure transducers (Honeywell model PPTR0040AP5VB-BD), which have been designed specially for long-term coastal oceanographic and limnological measurements, have been carried out at four differing temperatures (10°, 20°, 30°, and 40°C) to evaluate their suitability for such applications. The full-scale pressure range of these shallow water absolute pressure sensors is ≈ 2800 hPa (equivalent to water depth of ≈ 18 m). Measurement results have been used to examine the transducers’ performance indicators, such as zero-point offset, accuracy, linearity, hysteresis, temperature sensitivity, and slope. Differing piezoresistive ruggedized precision absolute pressure transducers (PPTRs) exhibited differing zero-point offset values, ranging from 2 to −79 hPa. Temperature sensitivity of zero-point offset was ≈0.3 hPa over the temperature range 10°–40°C. The mean hysteresis over the full-scale absolute pressure range (≈2800 hPa) varied from approximately 2 to 8 hPa over the temperature range 10°–40°C. The slope of the least squares–fitted linear graph (taking the mean of ascending and descending pressures) was close to the ideal value of unity (deviation from 1 over the temperature range 10°–40°C was in the range of −0.001 to +0.005). Linearity was excellent, its mean over the entire pressure range being between ≈ −0.006% and 0.008% of full-scale (FS) over the above temperature range. The worst performance was exhibited at input pressures below ≈1500 hPa. Zero-point offset has played a significant role in deteriorating the accuracy of the PPTR, the mean accuracy (within ≈0.1% and −5%) having been exhibited by those transducers having offsets of 2 and −79 hPa, respectively. The mean accuracy exhibited temperature sensitivity of ≈1% in the range 10°–20°C and negligible sensitivity beyond 20°C. Use of a calibration equation significantly improved the mean static accuracy obtainable from the PPTR, to between −0.04% and 0.01% of FS. Evaluation results have indicated that a suitably calibrated temperature-compensated Honeywell PPTR provides an alternate cost-effective means for pressure measurements for coastal oceanographic and limnological studies.

scholarly journals Miniature Implantable Pressure Sensors for Medical Applications

2010 ◽  
Vol 4 (2) ◽  
Author(s):  
Robert Stone ◽  
FranÃois Gardien ◽  
Antoine Filipe ◽  
Christian Pisella ◽  
Alain Roggi ◽  
...  
Keyword(s):  
Power Consumption ◽  
Fluid Pressure ◽  
Pressure Sensors ◽  
Form Factors ◽  
Full Scale ◽  
Absolute Pressure ◽  
Sensing Element ◽  
Sigma Delta ◽  
Temperature Range ◽  
Trade Offs

Pressure sensors are requisite for many medical implantable devices to monitor physiological pressures or fluid pressure and flow from a subsystem. Size, power consumption, accuracy, sensitivity, stability, and biocompatibility are all key considerations in the design and fabrication of such sensors. Conventional designs, based on piezoresistive technologies, are power consuming with significant drift and temperature error, whereas capacitive solutions are often cumbersome when packaged for biocompatibility. Tronics Microsystems has developed absolute pressure sensors, which achieve the benefits of both technologies. Miniaturization is achieved using a MEMS sensing element and a multifunction ASIC with small form factors. Low power consumption, low drift, high resolution, and waveform capture capability are obtained by using a capacitive MEMS coupled with a sigma-delta, direct capacitance to digital converter. Biocompatibility is achieved with grade II titanium packaging in two form factors (“tubular” or “pancake”) for incorporation into various applications. These sensors have been fabricated, calibrated, and tested extensively over physiologic temperature ranges. The design has achieved power consumption lower than 500 ÂμW at 100 Hz and a drift lower than 0.5% full scale per year. An accuracy of +/−1% full scale, over the temperature range is obtained by on-ASIC nonlinearity and temperature compensation. The two packaging configurations allow analysis of the trade-offs on the temperature range, sensitivity, volume, sterilization, etc. Different feed-through materials permit optimization of the form factors for the tube and the flat sensor and wired or wireless communication.

A resonant high-pressure sensor based on dual cavities

2021 ◽  
Vol 31 (12) ◽  
pp. 124002
Author(s):  
Jie Yu ◽  
Yulan Lu ◽  
Deyong Chen ◽  
Junbo Wang ◽  
Jian Chen ◽  
...  
Keyword(s):  
High Pressure ◽  
Temperature Sensitivity ◽  
Pressure Sensor ◽  
Pressure Range ◽  
High Vacuum ◽  
Pressure Sensors ◽  
Anodic Bonding ◽  
Temperature Range ◽  
Pressure Sensitive ◽  
Ocean Sciences

Abstract High-pressure sensors enable expansive demands in ocean sciences, industrial controls, and oil explorations. Successful sensor realized in piezoresistive high-pressure sensors which suffer from the key issue of compromised accuracies due to serious temperature drifts. Herein, this paper presents a high accuracy resonant high-pressure sensor with the pressure range of 70 MPa. Different from conventional resonant high-pressure sensor, the developed sensor utilized a dual-resonator-cavity design to minimize temperature disturbances and improve the pressure sensitivities. Besides, four circle cavities were used to maintain a high vacuum level for resonators after anodic bonding process. In details, Dual resonators, which is parallelly placed in the tensile and compressive stresses areas of a rectangular pressure sensitive diaphragm, are separated vacuum-packaged in the parallel dual cavities. Thus, pressure under measurement bends the pressure sensitive diaphragm, producing an increased pressure sensitivity and a decreased temperature sensitivity by the differential outputs of the dual resonators. Parameterized mathematical models of the sensor were established and the parameters of the models were optimized to adjust the pressure sensitivities and the temperature sensitivities of the sensor. Simplified deep reactive ion etching was used to form the sensing structure of the sensor and only once anodic bonding was used to form vacuum packaging for the dual resonators. Experimental results confirmed that the Q values of the resonators were higher than 32 000. Besides, the temperature sensitivity of the sensor was reduced from 44 Hz °C−1 (494 ppm °C−1) to 1 Hz °C−1 (11 ppm °C−1) by the differential outputs of the dual resonators in the temperature range of −10 °C–60 °C under the pressure of 1000 kPa. In addition, the accuracy of the sensor was better than 0.02% FS within the pressure range of 110–6500 kPa and the temperature range of −10 °C–60 °C by using a polynomial algorithm.

The thermodynamics of hydrocarbon solutions I. Technique of vapour-pressure measurements; the vapour pressure of benzene

1952 ◽  
Vol 212 (1109) ◽  
pp. 149-163 ◽  
Keyword(s):  
Standard Deviation ◽  
Recent Work ◽  
Satisfactory Agreement ◽  
Vapour Pressure ◽  
Pressure Range ◽  
Accurate Determination ◽  
Pressure Measurements ◽  
Temperature Range ◽  
The Mean

A technique has been developed for the accurate determination of vapour pressures of liquids in the temperature range 0 to 80° C and pressure range 5 to 760 mm of mercury. Measurements have been made of the vapour pressure of carefully purified benzene, and results have been obtained in satisfactory agreement with the best recent work. The standard deviation of the mean of eight determinations varies from ± 0 02 mm at 25° C to ± 0.11 mm at 75° C.

Relation of Statistically Significant, Abnormal, and Typical WAIS-R VIQ-PIQ Discrepancies to Full Scale IQs

2000 ◽  
Vol 16 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Louis M. Hsu ◽  
Judy Hayman ◽  
Judith Koch ◽  
Debbie Mandell
Keyword(s):  
Graphical Method ◽  
The United States ◽  
Full Scale ◽  
True Score ◽  
Absolute Value ◽  
Normative Population ◽  
The Us ◽  
The Mean ◽  
And Performance ◽  
Quadratic Models

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.

Non-isothermal crystallization behavior of spinel crystals in FeO-SiO2-TiO2-V2O3-Cr2O3 slag

2018 ◽  
Vol 116 (1) ◽  
pp. 110
Author(s):  
Lixiong Shao ◽  
Jiang Diao ◽  
Wang Zhou ◽  
Tao Zhang ◽  
Bing Xie
Keyword(s):  
Cooling Rate ◽  
Crystallization Behavior ◽  
Crystal Size ◽  
Growth Mechanisms ◽  
Vanadium Slag ◽  
Growth Behaviour ◽  
Temperature Range ◽  
Chromium Spinel ◽  
Mean Diameter ◽  
The Mean

The growth behaviour of spinel crystals in vanadium slag with high Cr2O3 content was investigated and clarified by statistical analyses based on the Crystal Size Distribution (CSD) theory. The results indicate that low cooling rate and Cr2O3 content benefit the growth of spinel crystals. The chromium spinel crystals firstly precipitated and then acted as the heterogeneous nuclei of vanadium and titanium spinel crystals. The growth mechanisms of the spinel crystals at the cooling rate of 5 K/min consist two regimes: firstly, nucleation control in the temperature range of 1873 to 1773 K, in which the shapes of CSD curves are asymptotic; secondly, surface and supply control within the temperature range of 1773 to 1473 K, in which the shapes of CSD curves are lognormal. The mean diameter of spinel crystals increases from 3.97 to 52.21 µm with the decrease of temperature from 1873 to 1473 K.

Dynamic Viscosity of Compressed Water to 10 Kilobar and Steam to 1500°C

1969 ◽  
Vol 11 (2) ◽  
pp. 189-205 ◽  
Author(s):  
E. A. Bruges ◽  
M. R. Gibson
Keyword(s):  
Gaseous Phase ◽  
Dynamic Viscosity ◽  
Low Temperatures ◽  
Pressure Range ◽  
Low Pressure ◽  
Temperature Range ◽  
Inversion Temperature ◽  
Pressure Steam ◽  
Correlating Equations ◽  
First Time

Equations specifying the dynamic viscosity of compressed water and steam are presented. In the temperature range 0-100cC the location of the inversion locus (mu) is defined for the first time with some precision. The low pressure steam results are re-correlated and a higher inversion temperature is indicated than that previously accepted. From 100 to 600°C values of viscosity are derived up to 3·5 kilobar and between 600 and 1500°C up to 1 kilobar. All the original observations in the gaseous phase have been corrected to a consistent set of densities and deviation plots for all the new correlations are given. Although the equations give values within the tolerances of the International Skeleton Table it is clear that the range and tolerances of the latter could with some advantage be revised to give twice the existing temperature range and over 10 times the existing pressure range at low temperatures. A list of the observations used and their deviations from the correlating equations is available as a separate publication.

scholarly journals Trends and Clinico-Epidemiological Features of Human Rabies Cases in Bangladesh, 2006–2018

2020 ◽  
Vol 41 (S1) ◽  
pp. s416-s416
Author(s):  
Sumon Ghosh ◽  
Md. Sohel Rana ◽  
Sukanta Chowdhury
Keyword(s):  
Effective Means ◽  
Scale Up ◽  
Traditional Healers ◽  
Human Rabies ◽  
Epidemiological Analysis ◽  
Increasing Trend ◽  
The Mean ◽  
Death Cases ◽  
Death Data

Background: Vaccinating dogs against rabies is an effective means of reducing human rabies. Methods: We analyzed 1,327 clinically diagnosed human rabies deaths and mass dog vaccination (MDV) data during 2006–2018 to quantify the impacts of MDV on human rabies incidence in Bangladesh and a subset of rabies death data (n = 422) for clinico-epidemiological analysis. Results: We found a positive and increasing trend of dog population vaccination (P = .01 and τ = 0.71) and a negative and declining trend (P < .001 and τ = −0.88) of human rabies cases (correlation coefficient, −0.82). Among 422 human rabies death cases, most victims (78%) sought treatment from traditional healers, and 12% received postexposure prophylaxis (PEP). The mean incubation period of rabies cases with exposure sites on the head and neck (35 days) was shorter than the upper limb (mean, 64 days; P = .02) and lower limb (mean, 89 days; P < .01). MDV is effective for reducing human rabies cases in Bangladesh. Conclusions: Creating awareness among the animal bite victims to stop relying on traditional healers rather seeking PEP, addressing the role of traditional healers through an awareness education program in respect to the treatment of dog bites, ensuring availability of PEP, and continuing to scale up MDV can help prevent human rabies deaths.Funding: NoneDisclosures: None

Temperature sensitivity in silicon piezoresistive pressure transducers

1983 ◽  
Vol 30 (7) ◽  
pp. 802-810 ◽  
Author(s):  
Sea-Chung Kim ◽  
K.D. Wise
Keyword(s):  
Temperature Sensitivity ◽  
Pressure Transducers

Routes towards Novel Active Pressure Sensors in SOI Technology

2011 ◽  
Vol 276 ◽  
pp. 145-155
Author(s):  
Benoit Olbrechts ◽  
Bertrand Rue ◽  
Thomas Pardoen ◽  
Denis Flandre ◽  
Jean Pierre Raskin
Keyword(s):  
Finite Elements ◽  
Strain Distribution ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Stress Strain ◽  
Pressure Transducers ◽  
Active Devices ◽  
Active Pressure ◽  
Soi Technology

In this paper, novel pressure sensors approach is proposed and described. Active devices and oscillating circuits are directly integrated on very thin dielectric membranes as pressure transducers. Involved patterning of the membrane is supposed to cause a drop of mechanical robustness. Finite elements simulations are performed in order to better understand stress/strain distribution and as an attempt to explain the early burst of patterned membranes. Smart circuit designs are reported as solutions with high sensitivity and reduced footprint on membranes.

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