| 1. |
- Bissig, Hugo, et al.
(författare)
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Calibration of insulin pumps based on discrete doses at given cycle times
- 2023
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Ingår i: Biomedizinische Technik (Berlin. Zeitschrift). - : De Gruyter Open Ltd. - 1862-278X .- 0013-5585. ; 68:1, s. 67-77
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Tidskriftsartikel (refereegranskat)abstract
- One application in the medical treatment at very small flow rates is the usage of an Insulin pump that delivers doses of insulin at constant cycle times for a specific basal rate as quasi-continuous insulin delivery, which is an important cornerstone in diabetes management. The calibration of these basal rates are performed by either gravimetric or optical methods, which have been developed within the European Metrology Program for Innovation and Research (EMPIR) Joint Research Project (JRP) 18HLT08 Metrology for drug delivery II (MeDDII). These measurement techniques are described in this paper, and an improved approach of the analytical procedure given in the standard IEC 60601-2-24:2012 for determining the discrete doses and the corresponding basal rates is discussed in detail. These improvements allow detailed follow up of dose cycle time and delivered doses as a function of time to identify some artefacts of the measurement method or malfunctioning of the insulin pump. Moreover, the calibration results of different basal rates and bolus deliveries for the gravimetric and the optical methods are also presented. Some analysis issues that should be addressed to prevent misinterpreting of the calibration results are discussed. One of the main issues is the average over a period of time which is an integer multiple of the cycle time to determine the basal rate with the analytical methods described in this paper.
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| 2. |
- Bissig, Hugo, et al.
(författare)
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In-line measurements of the physical and thermodynamic properties of single and multicomponent liquids
- 2023
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Ingår i: Biomedizinische Technik (Berlin. Zeitschrift). - : De Gruyter Open Ltd. - 1862-278X .- 0013-5585. ; 68:1, s. 39-50
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Tidskriftsartikel (refereegranskat)abstract
- Microfluidic devices are becoming increasingly important in various fields of pharmacy, flow chemistry and healthcare. In the embedded microchannel, the flow rates, the dynamic viscosity of the transported liquids and the fluid dynamic properties play an important role. Various functional auxiliary components of microfluidic devices such as flow restrictors, valves and flow meters need to be characterised with liquids used in several microfluidic applications. However, calibration with water does not always reflect the behaviour of the liquids used in the different applications. Therefore, several National Metrology Institutes (NMI) have developed micro-pipe viscometers for traceable inline measurement of the dynamic viscosity of liquids used in flow applications as part of the EMPIR 18HLT08 MeDDII project. These micro-pipe viscometers allow the calibration of any flow device at different flow rates and the calibration of the dynamic viscosity of the liquid or liquid mixture used under actual flow conditions. The validation of the micro-pipe viscometers has been performed either with traceable reference oils or with different liquids typically administered in hospitals, such as saline and/or glucose solutions or even glycerol-water mixtures for higher dynamic viscosities. Furthermore, measurement results of a commercially available device and a technology demonstrator for the inline measurement of dynamic viscosity and density are presented in this paper. © 2022 the author(s)
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| 3. |
- Büker, Oliver, et al.
(författare)
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A unique test facility for calibration of domestic flow meters under dynamic flow conditions
- 2021
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Ingår i: Flow Measurement and Instrumentation. - : Elsevier Ltd. - 0955-5986 .- 1873-6998. ; 79
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Tidskriftsartikel (refereegranskat)abstract
- In the early nineties a hot water test facility was planned and constructed for calibration and testing of volume and flow meters at the National Volume Measurement Laboratory at RISE (formerly SP Technical Research Institute of Sweden). The main feature of the test facility is the capability to measure flow in a wide temperature and flow range with very high accuracy. The objective of the project, which was initiated in 1989, was to design equipment for calibration of flow meters with stable flow and temperature conditions. After many years of international debate whether static testing is adequate to represent the later more dynamic application of domestic water meters, the EMPIR project 17IND13 Metrology for real-world domestic water metering (“Metrowamet”) was launched in 2018. The project investigates the influence of dynamic flow testing on the measurement accuracy of different types of domestic flow meters. One of the main objectives of the project is the development of infrastructure to carry out dynamic flow measurements. The existing test facility at RISE was at the time of construction one of the best hot and cold-water test facilities in the world. Due to the Metrowamet project the test facility has been upgraded to meet the needs of an infrastructure for dynamic flow investigations. The first findings from dynamic consumption profile measurements are reported in this paper. © 2021 The Authors
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| 4. |
- Büker, Oliver, et al.
(författare)
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Characterisation of a Coriolis flow meter for fuel consumption measurements in realistic drive cycle tests
- 2023
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Ingår i: Flow Measurement and Instrumentation. - : Elsevier Ltd. - 0955-5986 .- 1873-6998. ; 93
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Tidskriftsartikel (refereegranskat)abstract
- When testing light-duty and heavy-duty vehicles on chassis dynamometers, as in the WLTP, or engines on engine test benches, as in the WHDC, it is required to measure the fuel consumption. In the preferable case, the measurement of the fuel consumption is carried out with suitable flow meters. These require high measurement accuracy in a wide flow range, independent of the fuel type, as the flow rate range is often very large and depends on the power range of the vehicle engines. Moreover, the fuel flow rate in the test cycles is very dynamically related to the loads. In the scope of the ongoing EMPIR Joint Research Project 20IND13 SAFEST the dynamic flow behaviour as well as the measurement accuracy of flow meters for different types of fuels are investigated. This paper presents first results from the realisation of dynamic flow profiles, and flow measurements with a Coriolis Flow Meter with different representative fuels in a wide density and viscosity range and a wide flow rate range at different fuel temperatures. © 2023 The Author(s)
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| 5. |
- Büker, Oliver, et al.
(författare)
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Investigations on pressure dependence of Coriolis Mass Flow Meters used at Hydrogen Refueling Stations
- 2020
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Ingår i: Flow Measurement and Instrumentation. - : Elsevier Ltd. - 0955-5986 .- 1873-6998. ; 76
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Tidskriftsartikel (refereegranskat)abstract
- In the framework of the ongoing EMPIR JRP 16ENG01 “Metrology for Hydrogen Vehicles” a main task is to investigate the influence of pressure on the measurement accuracy of Coriolis Mass Flow Meters (CFM) used at Hydrogen Refueling Stations (HRS). At a HRS hydrogen is transferred at very high and changing pressures with simultaneously varying flow rates and temperatures. It is clearly very difficult for CFMs to achieve the current legal requirements with respect to mass flow measurement accuracy at these measurement conditions. As a result of the very dynamic filling process it was observed that the accuracy of mass flow measurement at different pressure ranges is not sufficient. At higher pressures it was found that particularly short refueling times cause significant measurement deviations. On this background it may be concluded that pressure has a great impact on the accuracy of mass flow measurement. To gain a deeper understanding of this matter RISE has built a unique high-pressure test facility. With the aid of this newly developed test rig it is possible to calibrate CFMs over a wide pressure and flow range with water or base oils as test medium. The test rig allows calibration measurements under the conditions prevailing at a 70MPa HRS regarding mass flows (up to 3.6kgmin−1) and pressures (up to 87.5MPa). © 2020 The Authors
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| 6. |
- Büker, Oliver, et al.
(författare)
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Investigations on the influence of total water hardness and ph value on the measurement accuracy of domestic cold water meters
- 2021
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Ingår i: Water. - : MDPI. - 2073-4441. ; 13:19
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Tidskriftsartikel (refereegranskat)abstract
- In the framework of the ongoing EMPIR Joint Research Project (JRP) 17IND13 Metrology for real-world domestic water metering (Metrowamet), a main task is to investigate the influence of realistic operation conditions, that is, typical water qualities (suspended particles, degree of hardness, and pH value), on the measurement accuracy. For this purpose, two representative types of cold water meters were investigated in more detail. Initially, the cold water meters were calibrated and then subjected to an accelerated wear test with water of different pH values and degrees of hardness. The accelerated wear tests were designed to reproduce the realistic use and service life of a cold water meter. Subsequently, the cold water meters were re-calibrated to assess the influence of the different water qualities on the measurement accuracy. One of the results was that the measurement accuracy of the water meters investigated was not strongly affected by the water quality. The practical realisation and the measurement results are reported in this paper. © 2021 by the authors.
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| 7. |
- Buker, O., et al.
(författare)
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Metrological support for LNG custody transfer and transport
- 2016
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Ingår i: Proceedings of the 17th International Flow Measurement Conference (FLOMEKO 2016).
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Konferensbidrag (refereegranskat)abstract
- In the framework of the ongoing EMRP Joint Research Project (JRP) ENG 60 “Metrology for LNG” (2014-2017), co-funded by the European Union, a number of metrological challenges associated with custody transfer and transport of LNG will be faced. The project consists of four technical work packages (WP), whereby the main objective is to reduce the measurement uncertainty of LNG custody transfer by a factor two. The focus in WP1 is the design and development of a traceable mid-scale calibration standard for LNG mass and volume flow. The goal is to provide traceable mass and volume flow calibrations up to 400 m3/h (180000 kg/h). In WP2, the emphasis is on the development and validation of a LNG sampling and composition measurement reference standard, consisting of sampler, vaporizer, gas standards, and gas chromatography (GC), which will be used to test and calibrate commercially available LNG sampling and composition measurement systems. The priority in WP3 is given to the development and validation of a method for the determination of the methane number, including correlations based on the LNG composition and corrections for traces of nitrogen and higher hydrocarbons. Since physical properties and quantities play an important role in LNG custody transfer, WP4 comprises reference quality density measurements of LNG to validate and improve models for LNG density predictions, the uncertainty evaluation of enthalpy and calorific value calculations and the development of a novel cryogenic sensor for the simultaneous measurement of speed-of-sound and density. The present paper gives an overview of recently achieved objectives within the project and provides an outlook to future activities.
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| 8. |
- Büker, Oliver, et al.
(författare)
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RISE Test Facilities for the Measurement of Ultra-Low Flow Rates and Volumes with a Focus on Medical Applications
- 2022
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Ingår i: Applied Sciences. - : MDPI. - 2076-3417. ; 12:16
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Tidskriftsartikel (refereegranskat)abstract
- In the framework of the ongoing EMPIR JRP 18HLT08 Metrology for Drug Delivery (MeDDII), a main task is to improve dosing accuracy and enable traceable measurements of volume, flow and pressure of existing drug delivery devices and in-line sensors operating, in some cases, at ultra-low flow rates. This can be achieved by developing new calibration methods and by expanding existing metrological infrastructure. The MeDDII project includes, among other issues, investigations on fast changing flow rates, physical properties of liquid mixtures and occlusion phenomena to avoid inaccurate measurement results and thus improve patient safety. This paper describes the extension of an existing measurement facility at RISE and the design and construction of a new measurement facility to be able to carry out such investigations. The new measurement facility, which is based on the dynamic gravimetric method, is unique worldwide in respect of the lowest measurable flow rate. The gravimetric measuring principle is pushed to the limits of what is feasible. Here, the smallest changes in the ambient conditions have a large influence on the measurement accuracy. The new infrastructure can be used to develop and validate novel calibration procedures for existing drug delivery devices over a wide flow rate range. The extension of the measurement facilities also enables inline measurement of the pressure and the dynamic viscosity of Newtonian liquids. For this purpose, it is ensured that all measurements are traceable to primary standards. © 2022 by the authors.
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| 9. |
- Jönsson, Gustav, et al.
(författare)
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Gas flow measurement of evaporated liquid nanoflows
- 2023
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Ingår i: Measurement. - 0263-2241 .- 1873-412X. ; 216
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Tidskriftsartikel (refereegranskat)abstract
- Following the miniaturisation of fluidic components, the demand for traceable measurements of micro and nanoflows is increasing in various technological fields such as pharmaceuticals, biotechnology and automotive industry. Gravimetric flow measurement methods are accurate at microflows and above, but have a lower limit of about 5nLmin−1. Several alternative approaches have been developed to circumvent this limit. Here a measurement setup and proof of principle is presented for a method measuring the gas flows generated by complete evaporation of liquid ethanol nanoflows. The gas flow measurement is based on the well-established method of determining the pressure drop across a geometrically precisely defined circular opening in the molecular flow regime. Liquid flow rates from a syringe pump in the range of 5nLmin−1 to 200nLmin−1 are measured with an expanded uncertainty as low as 340pLmin−1 at instantaneous flow rates. Strategies to further improve accuracy are discussed.
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| 10. |
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