Search

The aim of the work is to improve the methods of determining the standby time of transit recycling wagons at the sorting station. Systems analysis, analytical, graphical modeling, Ishikawi scheme and methods of comparing the performance of transit and local carriages were used. The reasons for the extra time lost by the wagons at the railway stations were given. Methods of adjusting the stopping time of wagons at the sorting station and their advantages, disadvantages and error rates were studied. The options and time costs of moving the wagon from one loading to the unloading location were analyzed, and the negative factors that cause the wagons to be overstayed at the sorting station were identified. In order to increase the level of performance of the sorting station performance and speed up the delivery of goods, a four-step method of reasonable standardization of the stopping time of wagons was recommended. This method allows you to analyze the time spent on each operation of the wagon on the road, to identify and eliminate inefficient time losses in a timely manner, to identify negative factors and increase the accuracy of standardization methods by 5-10%.

The small-strain shear modulus of soils and rocks is an important input parameter in geotechnical analyses. Its estimation using the resonant column apparatus relies on accurate knowledge of the rotational inertia of the apparatus’s active end. Due to the complex geometry of the active end, its inertia is typically found from a calibration exercise. In this study a range of aluminium calibration bars and steel masses were used to compare two different calibration exercises presented in the literature. The resulting values of active end inertia are shown to be highly method-dependent. The method of compensating for the drive connection stiffness by finding the apparatus resonant frequency is found to introduce errors at low stiffness. The combined use of calibration bars and masses reduces scatter but yields poor results for stiff bars. An alternative approach to mitigate both of these problems is suggested. Active end inertia is found to be constant using this alternative approach. While effects of base inertia and reaction mass inertia are found to be small for this apparatus, compliance of the drive system is shown to significantly reduce resonant frequencies at high stiffnesses which increases the apparent active end inertia. This reduction in resonant frequency is modelled and used to derive frequency correction factors, which reduce errors in shear modulus to within acceptable limits when using the constant value of active end inertia. This demonstrates the potential for increasing the limit of sample stiffness where sufficient calibration data are available.

The Distinct element method (DEM) is a promising approach to model the microscopic behaviour of granular materials, but the capability of the simulations to reproduce the mechanical response of real granular materials depends strongly on the contact model parameters utilized. The present study focuses on the calibration and validation of the rolling resistance linear model parameters for Cuxhaven sand based on the experimental results from triaxial and oedometer tests. A sensitivity analysis was conducted to explore the influence of contact model parameters on the sample preparation and the shear stage of triaxial tests. The influence of parameters like rolling resistance friction coefficient, inter-particle friction coefficient, effective modulus, and normal-to-shear stiffness ratio were investigated. For calibration of the DEM model, the input parameters were selected such that the simulations reproduce the macro mechanical characteristics like dilation angle, peak stress, and stiffness. The calibrated parameters were then validated by simulating a one-dimensional compression test. The results are in good agreement with the experiments, which proves the suitability of the calibrated parameters. In addition, the validated parameters were applied to investigate the mechanical behaviour including the evolution of contact force chains, non-coaxiality of principal stress and strain rate, and sample inhomogeneity during a simple shear test.

This paper presents a novel methodology for calibrating cup anemometers, addressing a critical need in the wind energy sector for accurate and reliable wind speed measurement. Ensuring measurement accuracy through calibration remains a major challenge. In response, a cost-effective alternative methodology is presented that takes advantage of statistical analysis techniques. York linear regression is applied for the estimation of calibration coefficients, a novelty in the context of cup anemometer calibration. The approach overcomes the limitations of traditional procedures reliant on wind tunnel facilities. Experimental validation of the proposed methodology, carried out with wind turbines placed at a height of 10 meters, demonstrates that a reliable calibration can be achieved even in sites with a low wind regime.

Traceability is of vital importance in metrology and is achieved by an unbroken chain of calibrations that relate the measurement result to a reference. Less clear is the temporal aspect of traceability, namely the determination of recalibration dates. Relevant standards require the conduction of recalibrations in a planned manner, and thus in general there is a calibration history consisting of a number of past calibrations for measurands that are part of the traceability chain. Nevertheless, commonly only the results of the last calibration of the standards of the traceability chain are considered when determining a measurement result. Furthermore, recalibration dates are often determined in a rather unscientific manner. Within this paper, a method is proposed to predict the current value of a measurand along with its uncertainty, taking into account all past calibrations. Based on the predetermined target measurement uncertainty of the measurand, it is possible to recognize the need for and thus to date recalibrations. The applicability of the method is investigated by examining the metrological compatibility of the predicted results with the results of subsequent calibrations of the calibration histories of a number of different standards. There is an explainable limitation of the applicability of the method to calibration histories that exhibit a correlation of time and the chosen calibration laboratory. However, the paper leads the way of future research to remedy the currently unsatisfying state regarding the handling of calibration histories and the determination of recalibration dates.

This paper presents the preliminary characterization of a new reduced-height CALORRE differential calorimeter designed and fabricated for the irradiation in the MITR within the framework of the CALOR-I program. The paper begins by focusing on the preparation of the irradiation campaign, providing a brief and concise description of the MITR core and the newly fabricated differential calorimeter assembly. Next, the paper presents the preliminary experimental characterization conducted under laboratory conditions. This section includes a detailed presentation of the updated experimental set-up and the key metrological characteristics of the sensor response obtained from the first experimental results. Furthermore, the paper estimates and highlights the responses of the calorimeter calculated by means of a 3-D numerical thermal model under real conditions considering local heat sources determined by the NRL of the MIT using MCNP code. In conclusion, the paper offers some final remarks and prospects to realize the irradiation campaign successfully.

This paper presents the study of a new innovative heat flow single-cell calorimeter dedicated to the measurement of the nuclear heating rate in research reactors. Before irradiating this type of sensor, it is necessary to characterize it under laboratory conditions to determine its metrological properties. A general description (design, geometry and materials nature) of this new calorimeter will be given, focusing on the motivations that led to its development. This part will be followed by a presentation of the experimental set-up and operating protocol used to characterize this sensor. The sensor sensitivity and response time will be quantified and discussed with a comparison of those obtained with previous calorimeters. In parallel with these experimental characterizations, parametric 3-D numerical simulations will be carried out using COMSOL Multiphysics software. These results, obtained both experimentally and numerically, will be compared to present a complete calorimeter study under laboratory conditions.

The measurement of response time of pulse oximeter lacks standardized method and proper thresholds and alternative measurement methods are needed to minimize error and improve efficiency in calibration method of pulse oximeter due to the increasing number of pulse oximeter variations distributed due to the covid 19 pandemic. This study aims to measure the Response Time (RT) of a finger pulse oximeter with 6 different types of conditioning to determine the RT mean and standard deviation in order to classify the pulse oximeter based on their types. We evaluated the response time of 50 finger pulse oximeters (20 patient monitor type, 8 handheld type, and 22 fingertip type) using 6 saturation and desaturation conditioning methods with a SpO2 Simulator. Quantitative analysis used to determine the initial threshold value. From 50 pulse oximeters found the fastest response pulse oximeter are fingertip type with mean time are 9.71 seconds and the most stable of each conditioning pulse oximeter are patient monitor type with the average RT 3.47 seconds, and Handheld type are put in the middle. With the conclusion that Patient monitor type are classified in monitoring class, Handheld type are classified both in monitoring and diagnostic class and Fingertip both classified in diagnostic and preventive class.

The determination of module temperature in a photovoltaic (PV) system is a crucial factor in PV modelling and the assessment of system health status. However, the scarcity of on-site temperature measurements poses a challenge, and existing PV temperature models encounter difficulties in accurately estimating temperatures in systems characterized by unique structural or locational attributes. This paper introduces a novel approach that enables the calibration of PV temperature models without relying on direct temperature measurements. Referred to as blind calibration, this method eliminates the requirement for temperature measurements, thus offering a promising solution to the aforementioned challenges. The method is validated using three datasets, demonstrating accurate PV temperature (TPV) estimation with mean absolute errors below 2 °C. The findings highlight the suitability of the proposed approach for various PV system types, while acknowledging limitations regarding certain system configurations.

Gas monitoring is a prerequisite to understanding the exchange, diffusion, and migration processes of natural gases within underground environments, which are involved in several applications such as geological sequestration of CO2. In this study, three different techniques (micro-GC, infrared, and Raman spectroscopies) were deployed on an experimental flooded borehole for monitoring purposes after CO2 injection. The aim was to develop a real-time chemical monitoring device to follow dissolved gas concentrations by measurements in water inside the borehole but also at the surface through a gas collection system in equilibrium with the borehole water. However, all three techniques must be calibrated to provide the most accurate quantitative data. For this, a first step of calibration in the laboratory was carried out. A new calibrations were required to determine partial pressure and/or concentrations of gases in water or in the gas collection system. For gas phase analysis, micro-GC, FTIR spectroscopy, and Raman spectroscopy were compared. New calibration of the micro-GC was done for CO2, CH4, and N2 with uncertainty from ±100 ppm to 1.5 mol% depending on the bulk concentration and the type of gas. The FTIR and Raman spectrometers were previously calibrated for CO2, and CO2, N2, O2, CH4, and H2O, respectively with an accuracy of 1–6% depending on concentration scale, gas and spectrometer. Dissolved CO2 in water was measured using a Raman spectrometer equipped with an immersion probe. The uncertainty on the predicted dissolved CO2 concentration and partial pressure was ±0.003 mol·kg−1 and ±0.05 bar, respectively.

Introduction: Pre-operative templating prior to hip arthroplasty has traditionally used implant-company-provided acetates, which assumed a magnification factor between 115% and 120%. In recent years, pre-operative planning has been performed with digital calibration devices, in order to calculate the magnification factor. However, these devices are not without their limitations and are not readily available at many institutions. As previous reports suggest a wide range of magnification factors, the determination of an optimal magnification factor is currently unclear. We investigated the relationship between obesity and gender on the magnification factor in order to improve the accuracy of pre-operative templating. Patients and methods: Ninety-seven consecutive pre-operative calibrated pelvic radiographs using the KingMark calibration were analyzed using the TraumaCad templating software. The magnification factor calculated by the software was considered the true magnification factor and analysis was made in order to assess the effect of sex and body mass index (BMI) on the magnification factor. A linear regression analysis was utilized to create a predictive model for optimal magnification factor value. Results: Magnification factor was significantly affected by sex (male, 120.0% vs. female 121.2%, p

Abstract Background Determining the relative ubiety between the camera and the laser projector in a line-structured light vision sensor is a classical yet important task. Typical calibration methods often confront problems, such as difficulty of producing the target precisely and introduction of perspective projection errors. Methods In this work, a new calibration method based on a concentric circle feature is introduced. The proposed method is based on geometrical properties and can reduce the perspective projection error. In our method, the vanishing line of the light plane is firstly deduced from the imaged concentric circles. Then the normal vector of the light plane is determined. Consequently, the complete expression can be confirmed from the principle of the intersecting planes. Results and conclusion The proposed method is simple and robustness as the basic theory is geometrical properties. Accuracy evaluation experiment shows that the accuracy of the calibration method can reach 0.07 mm within the view field of about 200 × 200 mm. This accuracy is comparable to the commonly used calibration method with a checkerboard planar target, whereas our target is simple to produce.

Abstract A dual-camera structured light system consisting of two cameras and a projector has been widely researched in three-dimensional (3D) profilometry. A vital step in these systems is 3D calibration. Existing calibration methods are time-consuming and complicated because each camera-projector pair is calibrated separately. In this paper, an improved calibration method is proposed to decrease the calibration effort by simplifying the extrinsic calibration of one camera-projector pair. It needs only two texture images to acquire the extrinsic parameters of the right camera-projector pair instead of 25 images (a texture image, 12 vertical, and 12 horizontal sinusoidal fringe patterns) and more complicated computations. A variant iterative closest point (ICP) algorithm was studied to match 3D cloud data sets for each camera-projector, and to reject outliers and invisible data automatically at each iterative step by using the proposed five criteria. Experimental results demonstrate that the proposed method is simple to operate and reaches the higher measurement accuracy of the shape data compared with the existing state of the art method.

This paper solves the problem of high-precision and flexible positioning of mobile manipulators. The target ball positioning tool is designed to be installed on the manipulator and calibrated. Then use binocular vision to locate the target ball positioning tool to realize the positioning of the mobile manipulator. The experimental measurement of the positioning accuracy is better than other positioning methods. The method of designing target ball positioning tool and adopting binocular vision positioning method has high precision and low cost.

During a severe accident in either sodium-cooled or water-cooled nuclear reactors, jets of molten nuclear fuel may impinge on the coolant resulting in fuel-coolant interactions (FCI). Experimental programs are being conducted to study this phenomenology and to support the development of severe accident models. Due to the optical opacity of the test section walls, sodium coolant, and the apparent optical opacity of water in the presence of intense ebullition, high-speed X-ray imaging is the preferred technique for FCI visualization. The configuration of these X-ray imaging systems, whereby the test section is installed between a fan-beam X-ray source and a scintillator-image intensifier projecting an image in the visual spectrum onto a high-speed camera, entails certain imaging artefacts and uncertainties. The X-ray imaging configuration requires precise calibration to enable detailed quantitative characterization of the FCI. To this end, ‘phantom’ models have been fabricated using polyethylene, either steel or hafnia powder, and empty cavities to represent sodium, molten fuel and sodium vapor phases respectively. A checkerboard configuration of the phantom enables calibration and correction for lens distortion artefacts which magnify features towards the edge of the field of view. Polydisperse steel ball configurations enable precise determination of the lower limit of detection and the estimation of parallax errors which introduce uncertainty in an object’s silhouette dimensions. Calibration experiments at the MELT facility determined lower limits of detection in the order of 4 mm for steel spheres, and 1.7-3.75 mm for vapor films around a molten jet.

This paper presents an experimental study of the calibration of a non-adiabatic single-cell calorimeter called KAROLINA. This type of sensor is used to quantify the nuclear heating rate inside MTRs (Material Testing Reactors). The calibration of this sensor type is carried out in laboratory conditions without irradiation. The calibration corresponds to a preliminary step, which is crucial to use this sensor in real conditions. In the case of the studied single-cell calorimeter owning no heating element, the calibration is realized with a specific test bench, called BERTAN, based on thermal transient regimes. First of all, the paper describes the methodology of the determination of the calorimeter sensitivity and the dedicated experimental set-up developed recently. Then the paper is devoted to a parametric study carried out on the KAROLINA single-cell calorimeter to determine the influence of several parameters on its thermal time constant (temperature, velocity, phase, method).

Thermo-luminescent detectors are currently used to measure gamma doses in the medical and environmental surveillance fields. During the past few years, the CEA Reactor Studies Division tested and validated the use of these detectors for gamma flux characterization and nuclear heating measurements in mixed neutron/gamma fields of low power reactors. Doses were comprised between a few mGy and a few Gy for dose rates up to a few Gy.h-1. However, in MTR or TRIGA reactors, the gamma flux level is much higher (> 1012 n/cm2/s) and the TLD currently in use (CaF2:Mn and 7LiF:Mg,Ti) and their readout protocols were no longer suitable for the resulting doses. In order to extend the applicable dose range up to ∼1 MGy (dose rate of a few kGy.h-1), several options were explored. On one side, some adjustments were made to the readout protocols of CaF2:Mn and 7LiF:Mg,Ti, notably by testing the use of filters to reduce the amount of light received by the reader PMT to avoid saturation. On the other side, a new type of TLD (LiF:Mg,Cu,P) with different Li enrichments (natural or enriched in 7Li) was tested. This paper presents the calibration measurements results performed in pure gamma fields, at the irradiation platform of the CEA Cadarache Radioprotection Division, between 250 mGy and 3 Gy for all detector types. In addition to the calibration, these measurements also studied the Mg,Cu,P-doped detectors response: reproducibility, dose rate dependence, incoming photon energy dependence, high temperature effect when reading TLD, etc. Results show that at low doses Mg,Cu,P-doped TLDs are slightly less stable than CaF2:Mn and 7LiF:Mg,Ti. The sensitivity modification after a high dose exposure seems to indicate that a new protocol readout should be defined for Mg,Cu,P-doped sensors (high temperature peak).

This paper deals with the CALORRE differential calorimeter patented by Aix-Marseille University and the CEA in 2015. Firstly, the paper focuses on the presentation of the first prototype of CALORRE calorimeter qualified under real conditions during the MARIA irradiation campaign in 2015. Then, a review of the studies restricted to one CALORRE calorimetric cell realized thanks to experimental characterizations under laboratory conditions is detailed. Several configurations were studied to determine the influence of the cell height, its horizontal fin geometry and the nature of the material of its structure on its response for a calibration protocol: linearity, sensitivity, range, reproducibility, response time and absolute temperatures. Finally, within the framework of the new CALORI project, an optimization of the calorimeter assembly and its design were carried out in order to remove contact thermal resistances and provide a new configuration of CALORRE calorimeter suited for the in-core water loop of the MIT reactor (2 W.g-1). The response of this new calorimeter is estimated thanks to thermal simulations.

Measurement technology has made an enormous progress in the last decade. With the advent of knowledge representation, various object-oriented models for measurement systems have been developed in the past. Most common limitations of all these models were not incorporating the uncertainty in the measurement process. In this paper, we proposed an object-oriented model depicting the information and knowledge flow in the measurement process, including the measurement uncertainty. The model has three major object classes, namely measurement planning, measurement system and analysis & documentation. These are further classified into sub-classes and relationships amongst them. Attributes and operations are also defined within the classes. This gives a practical and conceptual view of knowledge in the form of object-model for measurement processes. A case study is presented which evaluates the uncertainty of the measurement of a 100 mm gauge block, using both Type A and Type B evaluation methods of the GUM approach.This case study is very similar to the evaluation of calibration uncertainty of CMM. This model can be converted into semantic knowledge representation such as ontology of measurement process domain. Other use of this model is to support the quality engineering in manufacturing industry and research.

This paper concerns experimental and numerical works on a new differential calorimeter called CALORRE and validated recently under irradiation conditions in MARIA reactor at low nuclear absorbed dose rate level. Works focus on a specific configuration of CALORRE which was designed especially for the measurement of high nuclear energy deposition rates inside Material Testing Reactors. Due to the high level, a new calibration system was fabricated in order to determine the response of the new configuration under laboratory conditions for a very wide range of electrical power never applied in the literature. The response of the new configuration can be considered linear for this very wide range of electrical power. An analytical calculation shows the contribution of each heat transfer in specific zones. 3D thermal simulations performed by means of COMSOL Multiphysics under irradiation conditions give the predictions of the calorimeter behavior under real conditions (up to 20W.g−1).

The nuclear radiation energy deposition rate is a key value for the thermal design of experiments, on materials and nuclear fuels, carried out in experimental channels of nuclear research reactors. Studies are led for two kinds of sensor currently dedicated to quantifying this value and corresponding to calorimeter. Development of new sensors but also improvement of their calibration and their associated interpretation methods are necessary. These aims are possible by many ways such as numerical simulations of sensor, characterizations under laboratory conditions and experimental campaign under irradiation conditions. The calibration step under non-irradiation conditions represents a crucial phase. This phase requires the development of specific benches. The present paper focuses on a new thermal-transient bench and its use to perform calibration of a polish single-cell calorimeter. The new bench is detailed. First studies of the influence of external conditions (temperature, velocity) on the calorimeter sensitivity are presented and discussed.

A compact DT neutron generator (NG) based on the mixed-beam operation was used as a calibration neutron source in the latest in-situ calibration of neutron detectors at the Joint European Torus (JET). In order to meet the requirement for the total uncertainty of the neutron detector calibration below ±10 %, the neutron emission properties had to be experimentally characterized and reproduced through detailed modelling of the neutron source characteristics and geometry of the neutron generator. The detailed neutronics simulations were an essential part of both NG characterization and JET neutron detector calibration. The complex neutron emission properties of the NG were reproduced through a combination of simulations and highresolution neutron spectroscopy measurements. This meant that six different DT neutron source components resulting from NG's mixed beam operation were explicitly simulated and their relative intensities scaled based on experimentally obtained neutron spectrum measurements. Furthermore, the detailed model of the NG's geometry was produced based on information from the supplier of the NG and images from a computer tomography (CT) scan. Finally, the positioning of the neutron source inside the JET tokamak during in-situ calibration was reproduced based on the information from the remote handling system (RHS) at JET, the system responsible for the positioning of the source during the calibration experiment. The extensive effort presented in the paper significantly contributed to the total uncertainties of the calibration factors well within the target value of ±10 %.

Quality assurance is an integrated part of any calibration facility. The calibration facility as well as its customers are interested in the facility production outgoing quality. In most calibration labs the inspection of calibrated items is performed according to a suitable sampling inspection policy. Some of these policies are very good in assuring the quality of the calibration services they offer, but do not provide a clear assessment of the outgoing quality of the entire production of the facility. This paper has developed two methods of calculating the average outgoing quality (AOQ) of a calibration lab that uses a multistage sampling inspection policy. The policy structure is presented first along with the exact procedure of how to perform it by the inspectors and the methods to calculate the AOQ. The two methods differ from each another in the type of data required to calculate the AOQ. The first method requires the technicians’ production, the number of items subject to inspections and the number of failing items found. The second method requires only the number of technicians at each level of the multistage inspection policy. The verifications of the performances of two methods are accomplished by building a simulation model on an Excel worksheet. The model simulates the calibration facility with the right parameters, and then compares the two methods with the actual AOQ. The paper further discusses the advantages and disadvantages of each method in a broader context of quality assurance.

The Medium Energy Proton and Electron Detector (MEPED) on board the National Oceanic and Atmospheric Administration Polar Orbiting Environmental Satellites (NOAA POES) is known to degrade with time. In recent years a lot of effort has been put into calibrating the degraded proton detectors. We make use of previous work and show that the degradation of the detectors can be attributed to the radiation dose of each individual instrument. However, the effectiveness of the radiation in degrading the detector is modulated when it is weighted by the mean ap index, increasing the degradation rate in periods with high geomagnetic activity, and decreasing it through periods of low activity. When taking ap and the radiation dose into account, we find that the degradation rate is independent of spacecraft and detector pointing direction. We have developed a model to estimate the correction factor for all the MEPED detectors as a function of accumulated corrected flux and the ap index. We apply the routine to NOAA POES spacecraft starting with NOAA-15, including the European satellites MetOp-02 and MetOp-01, and estimate correction factors.

This paper presents the evaluation of the uncertainty for the length measurement of gauge blocks by optical interferometry. In order to improve the gauge block calibration method and to decrease measurement uncertainty the old Zeiss-Kösters gauge block interferometer has been modified and improved by DMDM (Directorate of Measures and Precious Metals of Serbia). The main modification of the interferometer covers introduction of two laser sources, as new wavelength standards, as well as new hardware system and interferometer software, developed to completely automate the calibration process. The validation of the new measurement procedure details the uncertainty budget. The measurement method and model equation, which serves as the basis for the uncertainty evaluation is described. The uncertainty evaluation is performed in accordance with the document JCGM 100:2008-Evaluation of measurement data – Guide to the expression of uncertainty in measurement (GUM).

Calibration of volumetric proving tanks can be done using different methods. For the calibration of large proving tanks the master meter method can be used as a good alternative to the volumetric transfer method or the gravimetric method. When the master meter method is used in most cases a positive displacement meter is used. A better option is to make use a Coriolis mass flow meter as the master meter. Test data is presented of a calibration of a proving tank with a nominal volume of 500 L. Small repeatability figures can be obtained of consecutive calibration runs with a Coriolis mass flow meter. Also the linearity of the meter factor curve of the Coriolis mass flow meter makes this a better option for the master meter method.

The accuracy of thermal conductivity measurements is even more requested for materials characterization in energy-efficient buildings field. ENEA-UTTMATF and CertiMaC research group, as national institute and private laboratory respectively, cooperate in development of new measurement and analysis methods applied to buildings materials and their performances. For what concerns this kind of measurements, an Heat Flow-meter Transducer (HFT) is used. In order to give to both customers and other research institutes involved in the same field (e.g. International Comparison or International Round Robin Tests) the most exhaustive evaluation of the tested material thermal conductivity, a complete uncertainty analysis is implemented on the HFT measures. This uncertainty analysis, developed accordingly to the international standards and with the contribution of INRiM Institute, is described in this paper.

This work concerns the calibration of trip distribution models issued from Transportation Planning. The optimal estimators are the global minima of a non-convex function. A mathematical result establishes that the solution is the limit of a sequence of means of convenient random variables. A population-based global optimization involving this representation and random perturbations of a local descent method is applied. Experiments are performed on classical test functions. In the application to the models of trip distribution, 4 sets of data, including real data are used. The results show that the use of the representation of the solution leads to a significant improvement and increases the robustness.

Hydrogen isclassified as New Energy and also considered as the most promising transportation fuel candidate in the future. Various pilots test of hydrogen fuel cell vehicles by the world's leading automotive industries since the last 50 years have begun to show bright spot in the utilization of hydrogen-based fuel cells as vehicle fuel. The electrolysis process of water (H2O) would produce H2 (hydrogen) and O2 (oxygen). The conventional method resulted in inconsistent volume and quality of HHO gas. However, the current development of HHO gas production through electrolysis process varies in term of materials, production process, design of certain tools, and technical modifications to obtain optimum results. In this research, the Hybrid Multistack TypeHHO generator has been designed and developed by combining two types of dry and wet cell generators. In this study using both cell type generator (wet and dry cell) or called as a hybrid type. Through the process of electrolysis in HHO enclosure space, the HHO gas was produced. The volume of HHO gas obtained from the HHO generator as an alternative fuel is strongly influenced by the electrical current supplied and the concentration of KOH catalyst used. The test was conducted with four stages of catalyst amount from 5.6g/L; 11.2g/L; 16.8g/L; and 22.4g/L. The applied current is linearly increased, with the increasing HHO gas production. It is proven when with the amount of catalyst used at 22.4g/L, the average HHO gas produced is 230.3mL/min. The author analyzes the performance of the generator in term of current and HHO gas production at a predetermined 12V constant voltage.

The main function of the cooling system is to control the temperature of the engine components and improve the performance of an engine. To know the flow and temperature distribution in the jacket cooling system for 6 cylinder diesel engine is analyzed using 1 dimensional method by using GT-Suite 1D simulation software package. The present work employs 1D simulation of water jacket in GT-ISE to perform a comprehensive study of mass-flow and thermal distribution over the inlet of the cooling package of a selected engine in several steady state operating points. The results show, that the suggested predictive method successfully captures the thermal effect of recirculation while reducing the necessity for calibration done by prototype testing.

VENUS-F is a fast zero power reactor with 30 wt% U fuel and Pb/Bi as a coolant simulator. Depending on the experimental configuration, various neutron spectra (fast, epithermal, and thermal islands) are present. This paper gives a review of the nuclear instrumentation that is applied for reactor control and in a large variety of physics experiments. Activation foils and fission chambers are used to measure spatial neutron flux profiles, spectrum indices, reactivity effects (with positive period and compensation method or the MSM method) and kinetic parameters (with the Rossi-alpha method). Fission chamber calibrations are performed in the standard irradiation fields of the BR1 reactor (prompt fission neutron spectrum and Maxwellian thermal neutron spectrum).

An intercomparison of terrestrial photovoltaic (PV) calibrations was performed among a number of European calibration and testing laboratories that participated in the European Metrology Research Program (EMRP) project “PhotoClass”. The purpose of this intercomparison was to evaluate the comparability of calibration and testing services within the stated uncertainties of the individual laboratories. The calibration objects were two world photovoltaic scale (WPVS)-type reference solar cells, one made from crystalline silicon and one made from GaAs. The calibration value (CV) was the short-circuit current under standard test conditions (ISTC). In conclusion, it was found that the CVs are all consistent within the stated uncertainties. This result strengthens the reliance in the calibration chain and in the PV calibration infrastructure in Europe.

Capacitive hygrometers are widely used in industrial and environmental measurements. One of the limitations of these sensors is their temperature dependence. While in temperatures beyond 50 °C the effect has been proven to be significant, for standard conditions in calibration laboratories the magnitude of this dependence has not been rigorously studied. This paper presents the analysis and results of a study of the temperature influence in the calibration of capacitive hygrometers designed for monitoring environmental conditions. Ninety measurements were taken on 15 models of capacitive hygrometers using a two-pressure humidity generator between 30%rh and 80%rh and temperatures from 20 to 30 °C. A three-way analysis of variance (ANOVA) was used to evaluate the data. The results show that the calibration correction is independent of the temperature for the conditions considered; however, there is a correlation between the temperature and the devices, indicating that the gradients in temperature affect each technology of fabrication in a different way.

A FDS-LC long counter was developed to monitor the neutron fluence at the HINEG facility. The response function and the effective centre of long counter were calculated by using SuperMC code. The calibration of this long counter was performed in Research Facility, China institute of atomic energy. The results of experimental and simulative characterization of the FDS-LC long counter are persented in this paper. The comparison of the measured results with the calculated results shown a good agreement within 5%.

We describe a calibration device for absolute pressure ranging from 5 kPa to 130 kPa whose relative uncertainty contribution (k = 1), including stability, repeatability and linearity is better than 1 Pa. The device is composed of a capacitance diaphragm gauge (CDG) and a resonant silicon gauge (RSG). The good long-term stability of the calibration slope of the RSG disseminated to the CDG which in turn allows one to master the offset of the RSG, is the reason for such a low uncertainty contribution. The metrological characterisation of this working standard is presented.

500 MPa pressure is considered as the common maximum pressure in most of the National Metrology Institutes worldwide; however, validation of the uncertainty in that range required a lot of work. NIS when recognized on, 2008 guaranteed big uncertainty value above 200 MPa due to the absence of international comparison at that time. This paper summarizes the results of a validation of 500 MPa range of hydraulic gauge pressure measurements carried out at NIS. The study covers the calibration through direct comparison and through using of a pressure sensor. The paper summarized the technical work carried out at the results of measurements and the effect of these results on NIS Calibration Measurements Capability. The validation also includes the comparison between the obtained results and pervious calibration of the same piston-cylinder assembly that calibrated against the NIST primary standard.

To reduce greenhouse gas emissions, energy retrofitting of building stock presents significant potential for energy savings. In the design stage, energy savings are usually assessed through Building Energy Simulation (BES). The main difficulty is to first assess the energy efficiency of the existing buildings, in other words, to calibrate the model. As calibration is an under determined problem, there is many solutions for building representation in simulation tools. In this paper, a method is proposed to assess not only energy savings but also their uncertainty. Meta models, using experimental designs, are used to identify many acceptable calibrations: sets of parameters that provide the most accurate representation of the building are retained to calculate energy savings. The method was applied on an existing office building modeled with the TRNsys BES. The meta model, using 13 parameters, is built with no more than 105 simulations. The evaluation of the meta model on thousands of new simulations gives a normalized mean bias error between the meta model and BES of

Magnetometers are widely used for LEO small satellites attitude determination and control system. In order to estimate satellite dynamics and control attitude accurately, scale factor and bias of magnetometer must be estimated. In this study a linear Kalman filter (LKF) based algorithm for the estimation of magnetometer biases and scale factors is proposed. Proposed algorithms are simulated through attitude dynamics of a small satellite.

CSIR-National Physical Laboratory (NPL) India is a National Metrology Institute (NMI), which disseminate traceability of the physical parameters in the country. In the field of microwave, it is one of the apex laboratories to provide traceability. In this paper, the method for precession measurement of effective source reflection coefficient using resistive power splitter and mismatch uncertainty evaluation are reported and discussed. Juroshek method is implemented in conjunction with Vector Network Analyzer (VNA) for mismatch uncertainty evaluation by measuring source reflection coefficient from measured S parameters. The measurement results and their associated uncertainty are presented and discussed from 1 MHz to 18 GHz of the resistive power splitter. The complex reflection coefficient of the effective source is determined using indigenously developed automation software. The method adopted is the most convenient way of measuring effective source reflection coefficient whose values are smaller than the manufacturer specs. The mismatch uncertainty has been improved, which is beneficial during the calibration of power sensors along with power meters.