A) Incorrect voltage supply for a bridge-type sensor. B) The correct use of bridge-type sensor involves the use of a reference voltage circuit. 

A) Incorrect voltage supply for a bridge-type sensor. B) The correct use of bridge-type sensor involves the use of a reference voltage circuit. 

Contexts in source publication

Context 1
... that the MPX201DP pressure transducer is a ratiometric device, it is necessary to provide a highly-stable voltage reference signal to achieve correct operation, regardless of voltage and temperature variations. It is common to find circuits that suggest the use of the voltage supply line to power up the pressure transducer (Fig. 9A). Unless the pressure transducer includes an internal voltage reference supply (i. e. it is a voltage compensated device), it is necessary to use a dedicated voltage reference circuit. (Fig. 9B). In terms of temperature variations, voltage reference circuits are specified in ppm/ o C (parts per million per degree centigrade). Consider a ...
Context 2
... of voltage and temperature variations. It is common to find circuits that suggest the use of the voltage supply line to power up the pressure transducer (Fig. 9A). Unless the pressure transducer includes an internal voltage reference supply (i. e. it is a voltage compensated device), it is necessary to use a dedicated voltage reference circuit. (Fig. 9B). In terms of temperature variations, voltage reference circuits are specified in ppm/ o C (parts per million per degree centigrade). Consider a reference circuit specified to change at a rate of 100ppm/ o C. If the circuit output value is 10V @ 20 o C, exposing the integrated circuit to a 50 o C would change the output from 10V to ...

Citations

... van Genuchten (1980); Durner (1994); Durner and Flühler (2006)). Hydraulic conductivity can be considered as an indispensable parameter for soil characterization, simulation of water and mass transport in vadose and saturated zone, management of soil organic matter and sustainable development of regional water resources (Gutierrez Gnecchi et al., 2011). ...
... Empirical methods based on systematic data collection are used as to correlate K s with soil properties like particle size, soil texture, pore size and relative effective porosity (Gootman et al., 2020;Gupta et al., 2020;Huang et al., 2019;Hwang et al., 2017;Picciafuoco et al., 2019;Vereecken et al., 2010Vereecken et al., , 1992Wösten et al., 1999). Experimental methods are distinguished in laboratory and field methods (Durner and Flühler, 2006;Gutierrez Gnecchi et al., 2011;Morbidelli et al., 2017). However, the adequacy and cost-effectiveness of these methods can often be a limiting factor in soil-water modeling applications. ...
... However, the adequacy and cost-effectiveness of these methods can often be a limiting factor in soil-water modeling applications. In this concept, although the number of methods and apparatuses used is quite large, it is still a need to elaborate new methodological approaches and instrumentation technologies to enhance the quality and quantity of reliable information and to provide alternative options to address the uncertainty of hydraulic parameters estimations (Gamie and De Smedt, 2018;Gutierrez Gnecchi et al., 2011;Zhang et al., 2007). A physical analogue for soil water movement can be modelled with the Hele-Shaw (Hele-Shaw, 1898) apparatus. ...
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Permeability is a vital parameter for the design and construction of structures involving ocean engineering. Based on the steady-state heat transfer theory and Darcy's law, a novel in-situ test method for permeability in saturated sandy porous media is introduced in this work. This approach aims to obtain permeability through the inversion of the measured temperatures. Temperatures measuring device with a constant heater was installed in an insulating experimental tank filled with sandy sediments of different permeability. Further, a numerical model based on the Finite Element method was simulated to validate the feasibility of the proposed method and accuracy of the experimental data. Besides, the results obtained by the constant head test were compared with those calculated by the novel in-situ test method, considering different surface temperatures of the heater and different sediments’ permeability. It shows that the permeability obtained by in-situ method are reliable and accurate (the accuracy is within one order of magnitude) in both numerical simulations and experimental tests. The effects of different surface temperatures of the heater and permeability of porous media on permeability calculation results were also discussed. The surface temperature was found that has little influence on permeability. And the proposed method is applicable when the permeability is higher than 10⁻¹² m². The findings can provide some reference to the in-situ measurement of submarine sediments' permeability.