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This study develops a calibration method for the porous media to properly model the interaction between waves and coastal structures using VARANS models. The proposed method estimates the porosity, n p , and the optimum values of the Forchheimer coefficients, α and β , that best represent the wave-structure interaction for a complete set of laboratory tests. Physical tests were conducted in a 2D wave flume for a homogeneous mound breakwater under regular wave conditions. Numerical tests were carried out using the IH-2VOF model to simulate the corresponding physical tests and incident wave conditions (H I , T). The numerical tests covered a wide range of Forchheimer coefficients found in the literature, α and β , and the porosity, n p , with a total of 555 numerical tests. The results of 375 numerical tests using IH-2VOF were used to train a Neural Network (NN) model with five input variables (H I , T , n p , α and β) and one output variable (K R 2). The NN model explained more than 90% (R2 > 0.90 and RMSE <5%) of the variance of the squared coefficient of reflection, K R 2. This NN model was used to estimate the K R 2 in a wide range of n p , α and β , and the error (ε a) between the physical measurements with regular waves and the NN estimations of K R 2 was calculated. The results of ε a as function of n p , α and β showed that for a given porosity, n p , it was difficult to obtain a pair of α and β values that gave a common low error if few physical tests are used for calibration. Then to calibrate properly a VARANS model it seems necessary to check the results obtained for each combination of α and β with many laboratory { H I , T } tests. The minimum root-mean-square error of K R 2 (ε r m s) was calculated to find the optimum values of porosity and Forchheimer coefficients: n p = 0.44 , α = 200 and β = 2.825 for the tested structure. Blind tests were conducted with the remaining 180 numerical tests using IH-2VOF to validate the proposed method for VARANS models. In this study, eight or more physical tests were required to find adequate values of n p , α and β for VARANS models related to the best performance of wave-porous structure interaction. • A Neural Network model to predict K R 2 on mound breakwaters much faster than any numerical VARANS model. • The physical measurement of the porosity, n p , is not reliable and it should be calibrated. • The selection of few physical tests (H I , T) to calibrate Forchheimer coefficients, α and β , is not sufficient to obtain the best performance of wave-porous structure interaction. • The proposed method based on a Neural Network model is a robust, accurate and computational efficient tool to calibrate {n p , α and β } in VARANS models. • The proposed calibration method obtains the optimum combination of {n p , α and β } related to the best performance of wave-porous structure interaction. [ABSTRACT FROM AUTHOR]

Tracking scapular motion can be challenging. More research is needed to determine the best practices for scapular measurement in multi-planar tasks. The purpose of this study was to compare the repeatability of scapular kinematics during a functional task protocol calculated from different calibration procedures. It was hypothesized that select poses would improve repeatability in specific tasks. The torso, humerus, and scapula were tracked with optical motion capture in two sessions for ten pain-free participants. Scapular calibrations were completed in five poses: neutral, maximum elevation, 90° abduction, hand to contralateral shoulder, and hand to back. Each participant completed eight functional tasks (Comb Hair, Wash Axilla, Tie Apron, Overhead Reach, Side Reach, Forward Transfer, Floor Lift, Overhead Lift). Scapular angles were calculated with five different calibration procedures and extracted at 30° increments of humeral elevation in each task. Mean difference, limits of agreement, intraclass correlations, and minimal detectable change (MDC) were calculated for each task and elevation level. The inclusion of different calibration poses did not markedly improve outcomes over the maximum elevation double calibration for most tasks. Using this calibration procedure, median MDCs were 10.0° for upward rotation, 13.7° for internal rotation, and 9.8° for tilt. [ABSTRACT FROM AUTHOR]

• A structural model of direct measurement is introduced with a bottom-up presentation. • The model highlights the role of measuring instruments in measurement. • The model justifies that measurement has both empirical and informational components. • The model explains the role of scales and calibration in measurement. In the last few decades foundations of measurement have developed so as to account for both the role of modeling in measurement, in particular relating to the presence and the effects of measurement uncertainty, and the fact that any measurement is performed by using instruments that work on the basis of transduction effects and provide justified results only in so far as they are properly calibrated. This has triggered a new interest about the role of instruments in the models of measurement. The structure of the process has been variously studied in reference to the connection between measured properties and indications provided by instruments, and to the way in which intersubjective information on the measurand is acquired through instrument calibration. From such a background this paper proposes a comprehensive structural model of direct measurement, whose functional elements, empirical and informational, are presented with a bottom-up strategy as a set of interrelated modules. The result, shown to be a generalization of some of the models currently available in the literature of measurement science, highlights the key role of scales for measurement, clarifies the conceptual and operative relations between direct measurement and calibration, and identifies the principal sources of measurement uncertainty in the structural context of the process. This model is intended to interpret both physical and non-physical measurements, and as such it is a component of a "measurement across the sciences" research programme. [ABSTRACT FROM AUTHOR]

Abstract Load and Resistance Factor Design (LRFD) optimization is concerned with calibrating load and resistance factors against a pre-defined target safety level. The uncertainty in soil properties, the incomplete understanding of soil-structure interaction and the lack of statistical information slowed the development in the field of foundation optimization. A unified target reliability index is proposed for the design of a single pile, a non-redundant pile group, and a redundant pile group foundation. Resistance factors for axially loaded drilled and driven piles based on the statistical results of over 4000 pile load tests were calibrated using the proposed approach. [ABSTRACT FROM AUTHOR]

Highlights • Low yield point steel LYP100 is tested under large strain range. • The proposed constitutive model can well predict the cyclic behavior of LYP100. • The numerical algorithm is concise due to the particular evolution rule. • The optimization method simplifies the parameters calibration greatly. Abstract Low yield point (LYP) steel is a promising material for energy dissipation device resisting seismic actions, and is expected to experience large strain when subjected to strong earthquakes. In order to offer a better understanding of the cyclic behavior of LYP steel under large strain range, cyclic tests of eight (8) coupons made of LYP100 under the strain amplitude ranging from −10% to +12% are performed. Evident work-hardening, early re-yielding, and strain range dependence are characterized in the cyclic loading tests. To illustrate these characteristics, the peak stress of every cyclic loop and the elastic region of the unloading process are examined. Based on the analysis results of the peak stress and the elastic region, a modified Yoshida-Uemori model is proposed to quantify the cyclic behavior of LYP100, and the corresponding numerical algorithm is developed. In addition, a practical method based on the derivative-free optimization theory is proposed to calibrate the material parameters of the novel model. The proposed constitutive model shows a satisfactory accuracy for describing the cyclic behavior of LYP100 under large strain range. [ABSTRACT FROM AUTHOR]

Abstract The quantitative determination of radionuclides by gamma ray spectrometry requires a high accuracy of detection efficiency determination. Different software codes for efficiency determination are available. The aim of this work was to compare different methods and software used for efficiency calibration modeling and analyses. For that purpose, same samples of vegetation and soil of known activities were measured using HPGe detectors in two laboratories which are employing different software for mathematical efficiency calibrations and analyses, LabSOCS which is based on purely mathematical calculations and Angle which uses a semi-empirical approach. The codes were also tested on samples with unknown reference values (different geometries and matrices). The main advantages and disadvantages of both software were compared. Both Angle and LabSOCS gave comparable and consistent results for different detectors, matrices and geometries used. Deviations of the order of 10% or less obtained from the comparison of different sets of parameters are acceptable and imply that Angle and LabSOCS can be considered reliable for gamma ray detector efficiency calibrations. The main limitation of LabSOCS is in its inability to be used on newly installed detectors (factory characterization needed first), as for Angle the main drawback is in its demand for reference materials which can be costly as well as the need for plenty detector characteristics which are not always provided by the manufacturer. Highlights • Efficiency calibration of HPGe detectors using different mathematical models (LabSOCS vs. Angle). • The main advantages and disadvantages of both software were compared. • Both Angle and LabSOCS gave comparable and consistent results for different detectors, matrices and geometries used. • The main limitation of LabSOCS is in its inability to be used on newly installed detectors. • For Angle the main drawback is in its demand for reference materials and for plenty detector characteristics. [ABSTRACT FROM AUTHOR]

Abstract A novel method combining with continuous wavelet transform and ratio spectra derivative is proposed for simultaneous determination of copper, cobalt and nickel in industrial wastewater by UV–vis spectrometry, without separation step. The derivative calculation by continuous wavelet transform (CWT) using Haar wavelet function is found suitable for noisy signals. The ratio derivative value is measured at zero-crossing wavelength. The linear ranges of calibration graphs are up to 3 mg /L for copper, cobalt and nickel. The root mean squared error of prediction (RMSEP) for copper, cobalt and nickel is 0.073, 0.064 and 0.131, respectively. The mean relative deviations of copper, cobalt and nickel are all less than 5%. The results indicate that the proposed method is rapid, inexpensive, and more accurate than partial least square method. Therefore, it is suitable for analyzing overlapping spectra in their mixtures. [ABSTRACT FROM AUTHOR]

Highlights • Calibrate multiple virtual binocular system using a single image. • A system composed of four virtual binocular structures is designed. • Calibration experiment is performed using artificial 3D calibration target. • A practical 3D measurement is performed using the calibrated system. Abstract The virtual binocular vision system (VBVS) based on single camera and mirrors has been paid increasing attention, with the advantages of high flexibility and compactness. However, in its calibration process, the conventional methods require several images and obtain different intrinsic parameters, which should be identical between different virtual cameras. To simplify the calibration process and obtain identical intrinsic parameters, a single-image calibration method for the VBVS based on one camera and mirrors is proposed. Through the single image including multiple sub-images of the calibration planes, the intrinsic parameters and distortion coefficients can be obtained. Then, the global calibration of multiple virtual binocular structures can be performed efficiently. To test the performance of the proposed approach, a VBVS composed of four pairs of virtual binocular structures was designed and the calibration experiments were performed using an artificial three-dimensional calibration target. Moreover, an accuracy comparison with the conventional method was carried out. The results exhibited the feasibility of this method and proved its accuracy. [ABSTRACT FROM AUTHOR]

Abstract Numerical simulations of the LEAP centrifuge tests are performed to validate the numerical modeling approach and to provide insight on our capacity to simulate and predict the equivalent field responses. Measured and recorded dissipation patterns, accelerations, and displacements for a sloping ground of medium dense Ottawa Sand subjected to a sinusoidal acceleration input motion are compared to Class A and C [12] numerical predictions performed in FLAC using the constitutive model PM4Sand. The constitutive model calibration process is based on two cases of cyclic strength for the sand and is performed against the available laboratory data as well as published data for Ottawa sand. Computed results are illustrated for selected cases and compared to measurements. Key observations, mechanisms, and time histories are reasonably captured and bounded by the simulations showing that FLAC, PM4Sand as well as the overall employed methodology have the capability to predict the response of liquefiable sloping ground. The soil properties are found to be playing the most important role in capturing the finer details of the response, and parametric investigations of the soil stiffness and permeability are further needed to refine the predictions. Highlights • Class A and Class B predictions performed for three out of the six centrifuge tests performed within LEAP. • Numerical simulations performed in FLAC 7.0 with PM4Sand Version 3. • Calibration against lab test results as well as literature targeted at capturing the expected response ranges. • Satisfactory comparison between measured and simulated responses. • Accurate soil properties are key in refining the predictions. [ABSTRACT FROM AUTHOR]

We investigate terahertz transmission properties and electromagnetic resonance modes in the asymmetric triangle structures with the change of asymmetric distance and the direction of electric field. When the THz electric field is perpendicular to the split gap of triangle, the electric field can better excite the THz absorption in the triangle structures. Importantly, electromagnetically induced transparency (EIT) characteristics are observed in the triangle structures due to the destructive interference of the different excited modes. The distributions of electric field and surface current density simulated by finite difference time domain indicate that the bright mode is excited by the side of triangle structures and dark mode is excited by the gap-side of triangle. The present study is helpful to understand the electromagnetic resonance in the asymmetric triangular metamaterials. [ABSTRACT FROM AUTHOR]

The procedure followed by the Nuclear Metrology Laboratory (LMN) at the IPEN for the standardization of activity of 64 Cu is described. The measurement was carried out in a 4π (PC) β-γ coincidence system. The activity per unit mass of the solution was determined by the extrapolation technique. The events were registered using a Time to Amplitude Converter (TAC) associated with a Multi-channel Analyzer. The gamma-ray emission probability per decay of the 1345.7 keV transition of 64 Cu determined with a calibrated REGe gamma-ray spectrometer was (0.472 ± 0.010) %, in agreement with the literature. [ABSTRACT FROM AUTHOR]

The main features of code SUMCOR developed for cascade summing correction for volumetric sources are described. MCNP6 is used to track histories starting from individual points inside the volumetric source, for each set of cascade transitions from the radionuclide. Total and FEP efficiencies are calculated for all gamma-rays and X-rays involved in the cascade. Cascade summing correction is based on the matrix formalism developed by Semkow et al. (1990). Results are presented applying the experimental data sent to the participants of two intercomparisons organized by the ICRM-GSWG and coordinated by Dr. Marie-Cristine Lépy from the Laboratoire National Henri Becquerel (LNE-LNHB), CEA, in 2008 and 2010, respectively and compared to the other participants in the intercomparisons. [ABSTRACT FROM AUTHOR]

The aim of the work was to develop new radioactive standard sources based on epoxy resins. The optimal proportions of the components and the homogeneity of the matrices were determined. The activity of multigamma sources prepared in Marinelli beakers was determined with reference to the National Standard of Radionuclides Activity in Poland. The difference of radionuclides activity values determined using calibrated gamma spectrometer and the activity of standard solutions used are in most cases significantly lower than measurement uncertainty limits. Sources production method and quality control procedure have been developed. [ABSTRACT FROM AUTHOR]

The effect of the intrinsic inhomogeneity of a sample on the efficiency for the measurement of the sample by gamma-ray spectrometry is studied. The difference between the efficiency for the inhomogeneous sample and the efficiency for a sample made from the equivalent homogeneous matrix is evaluated. [ABSTRACT FROM AUTHOR]

A portable instrument was developed at the Institute of Radiation Physics (IRA) for on-site radionuclides measurements. It will enable the measurement of short-lived radionuclides in nuclear medicine departments or isotope production centres. The system involves an ionization chamber read directly by an electrometer and it was optimized to ensure a good reproducibility through the selection of an appropriate vial, filling volume and source position in the well chamber, as well as monitoring the external background and performing a detailed uncertainty estimation. The calibration factors were determined using solutions whose activity concentration is traceable to the international reference system using the IRA reference chamber. Currently the transfer ionization chamber is calibrated for F-18, C-11, O-15, N-13, I-131 and Tc-99m. The final instrument is able to measure isotope activities with a relative standard uncertainty not larger than 1%. [ABSTRACT FROM AUTHOR]

This paper describes the standardization of 67 Cu by the 4πβ(PC)-γ coincidence method, and the calibration of ionization chamber. The difficulties were. (i) One of the excited levels of 67 Zn has a half life of 9.10 μs. (ii) A recent publication reconsiders the decay scheme parameters. (iii) The solution had a significant content of impurities. The conclusions were that the result of absolute standardization is less influenced by the decay scheme parameters and impurities than the measurements by ionization chamber. [ABSTRACT FROM AUTHOR]

This paper presents a novel technique for the automatic calibration of motion capture systems composed of multiple Time of Flight cameras (ToF) or any equivalent device able to provide 3D point clouds together with chromatic information. The calibration procedure is designed to be simple, fast and unsupervised: a colored sphere moved freely by hand is used as calibration tool. Three elements in particular distinguish the method we propose from other state of the art solutions: it takes into account and propagates measurement uncertainties, it allows the identification and recovery of systematic time delays in camera synchronization, it optimize the extrinsic parameters by means of a graph based approach. A widely used ToF, Microsoft Kinect V2, was used for the comparison with state of the art multi-ToF calibration techniques. Experimental results demonstrated that the proposed method is the most accurate both in terms of shape reconstruction and spatial consistency. Furthermore, the experimental results underlined that the application of the global graph optimization over a more standard couple-based unweighed matching achieves a higher accuracy in the assessment of the extrinsic parameters. Thus enabling the reduction of both systematic errors and data dispersion in 3D point clouds of reference shapes. The comparison among acquisition systems composed of 3 and 6 devices underlined that graph optimization becomes relevant when the number of devices grows. Taking into account several 3D configurations calibrated with the proposed method, it was assessed that the uncertainty of the extrinsic parameters is generally lower than 2 mm and 1 0 − 2 radiants, 0.6°. The resulting dense 3D reconstruction of objects, both static and in motion, achieved experimental errors lower than to 10 mm, approximately half of other state of the art methods, and, in first approximation, homogeneous for the entire monitored area. The software developed can be found at the site of the MIRo lab (Measurement Instrumentation and Robotics lab) at link 1 under the Creative Commons Attribution conditions. [ABSTRACT FROM AUTHOR]

Measuring rail profile in the presence of multiple degrees of freedom vibration is a very challenging task. This paper presents a novel method based on the local affine invariant feature descriptor to calibrate distorted profiles, which are obtained by traditional rail measurement system. It has three major modules: local affine invariant (LAI) feature descriptor, affine transformation estimation and parameters refinement. LAI feature descriptor is based on the affine geometry invariant and generated by calculating the proportions of different areas. Using the proposed LAI descriptor, we implement a three-stage profile calibration including matching, estimation, and refinement based on grouping and fast iterative closest point (FICP) algorithm. The performance of proposed LAI descriptor and calibrating method is tested by performing extensive experiments. The experimental results show that our LAI descriptor is highly descriptive and robust with respect to varying resolution and noise, and the LAI descriptor based calibration is effective and repeatable. [ABSTRACT FROM AUTHOR]

Power clamp meters are designed to check electricity meters, instrument transformers and installations on site. A measurement technique which is used to calibrate current coils for calibration of power clamp meters in AC current range from 5 to 1000 A has been developed. This technique allows one to measure two parameters of current coils that are needed for calibration of power clamp meters, they are the amplitude coil effect and the proposed phase coil effect. This is the first study of phase coil effect. There is presented the calibration procedure and an example solution of a fully automatic calibration system which employs the three phase Power/Energy Calibrator from Poland, which is traceable to the national standards. Calibration uncertainty of current coils, with reference to a power calibrator and measurement results, is discussed. The best expanded uncertainty (k = 2) of this technique equals 0.03% for amplitude coil effect and it equals 0.14° for phase coil effect. The expanded uncertainty for phase coil effect equal 0.14° gives expanded uncertainty for active power equal 0.42% at PF = 0.5 for calibration of power clamp meters. The result is that the power clamp meters specified accuracy (0.40%) has almost the same value as the power error due to the influence of phase coil effect (0.42%). [ABSTRACT FROM AUTHOR]

In this study, the calibrations of the lower-limb kinematics based on the five wearable IMU sensors were performed to reduce the inherent kinematic errors due to the both incorrect measurements of the kinematic parameters and the uncertainties of the geometric modeling of the lower-limb joints. Unlike the actual body structure, the ankle and knee joint of the lower-limb part are generally modeled as pure revolute joints of two or three degrees of freedom with some assumptions. However, it is obvious that these mismatches in the simplified geometrical modeling of the joint in the lower-limb kinematics lead to uncertainties in the model-based 3D motion tracking of human body such as walking velocity estimation, gait analysis, etc. As main research contributions, we intended to examine exactly which error factors are responsible for the kinematic uncertainties that arises from the 3D motion tracking based on the lower-limb kinematics and wearable IMU sensors. The lower-limb kinematics model in this research assumes that the ankle, knee, and hip joints are all three degrees of freedom, and that the three principle axes at each joint may not intersect at a common point. That is, the kinematic uncertainties included in the joint model will be confirmed by performing a kinematic calibration taking into account the orientation of joint axes and joint offsets as kinematic error parameters as well as the case of only calibrating the link lengths. This study also uses a new calibration plate with seven sole-shaped jigs and five wearable IMU sensors to measure the actual pose of the right foot, which is the distal end of the lower-limb kinematics with respect to the left foot. In order to secure an in-depth insight into the wearable IMU sensor based calibrations of the lower-limb kinematics, the seven sole-shaped jigs were designed to independently allow the right foot on those jigs to have predefined 3-dof poses. Finally, an iterative least square method is adopted to minimize the error between the nominal kinematic model-based pose and the actual poses of the right foot with respect to the left foot on the calibration plate. In an experiment with one subject, the reduction rate of the position error depends on the measurement of the initial kinematic parameters, but the RMS position error of the right foot relative to the left foot was improved by 336.1% from 36.5 mm to 11.3 mm. [ABSTRACT FROM AUTHOR]

The static calibration of two MEMS calorimetric shear-stress sensors is performed. In a first step, a calibration range of τ w = ± 2 Pa is obtained in a two-dimensional channel-flow facility. The long-term repeatability of the sensors output, over a two-weeks period, is shown to be very good, with a standard deviation of less than 1% of the mean. In a second step, the sensors are calibrated in a large subsonic wind tunnel up to a velocity of 100 m/s, which corresponds to a range of τ w = ± 14 Pa of wall shear-stress that is closer to realistic values in low-speed aerodynamic flows. A method to measure the frequency response of the calorimetric sensors is also proposed. At an average wall shear-stress of τ w ¯ = 1 Pa, the sensors exhibit a cut-off frequency of approximately 1 kHz. Finally, the strong influence of the inter-beam distance on the static and dynamic characteristics of calorimetric sensors is demonstrated. 1 1 An early version of this article was first presented at the 52nd 3AF International Conference on Applied Aerodynamics (Lyon, France) on March 29, 2017. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the literature on tangential composite and radial composite gear inspection. It demonstrates – by dealing with their origins and key milestones in their history and development – the important role that inspections play in terms of the functional nature of the gears concerned. This comprehensive consideration of the subject also attempts to demonstrate how the lack of clear guidelines and standards designed to unify the criteria applied to testing, the interpretation of results and calibration of equipment, along with the number of simultaneous variables involved in trials of this type, leads to doubts (including with respect to the actual standards concerned) as to whether these tests are valid, or instead accepted only has partial validations. Even so, the repeatability of the experimental data demonstrates not only their metrological potential, with respect to functionality, but also the fact that they are both effective and original [ABSTRACT FROM AUTHOR]

In this manuscript, a novel method for multi-robots system calibration utilizing a calibration model based on the Product of Exponentials formula (POE formula) without nominal kinematic parameters is proposed. The calibration model is characterized by the adjoint transformation which is adopted to represent the transformation relationship between two twists. Compared with the traditional POE formula model for calibration, the proposed model merely depends on the reference configuration rather than base frame and reference configuration. Then a coordinate which describes the robot is fixed and the end-effector pose with respect to the predetermined coordinate is measured several times. Least square method is adopted to identify the exact POE formula model with respect to the predetermined coordinate. The results of simulation and experiment reveal that 1) with the proposed model, nominal kinematic parameters are not required to establish the initial kinematic equation, 2) the result of the calibration is not only identifying the exact kinematic parameters of the robot but also determining the pose of the robot base frame with respect to a predetermined coordinate, 3) the calibration method can increase the accuracy of multi-robots system. [ABSTRACT FROM AUTHOR]

Modern palynological investigations (pollen and non-pollen palynomorphs) have been carried out for the first time in the entire Bay of Brest (BB; NW France), a semi-enclosed oceanic basin flooded during the Holocene that today is exposed to both marine (North Atlantic surface waters) and fluvial (Aulne and Elorn rivers) influences. Palynological analyses were conducted on 41 surface sediments collected in several mudded bays where low-energy conditions prevail, allowing for fine particle decantation, and also on 12 moss samples considered to be pollen rain collectors taken on the periphery of the BB. Furthermore, the BB allows a direct comparison between landscapes and fossilized pollen assemblages in sediments thanks to relatively small watersheds and well-studied vegetation cover on land. Our data display a well-known distortion between pollen taxa percentages calculated from palynological slides and current vegetation cover on land, with a particular overestimation of arboreal taxa as well as an underestimation of herbaceous ones, especially of cereal crops that represent a major component of the regional continental vegetation. Various factors may be involved, including pollen transport issues, taphonomic processes, and different pollination rates according to trees/herbaceous taxa. Under close examination, we find that while all surface sediments show the same major species, palynological maps established in the BB regarding some specific pollen taxa exhibit differences and upstream-downstream gradients. Also, the comparison between the pollen content in BB surface sediments and in mosses supports the hydrodynamic influence acting on the pollen distribution in sediments. More specifically, we suggest that some arboreal taxa reflect a watershed effect, especially Alnus , which seems to be highly correlated to river influences and could therefore be considered as a potential proxy for fluvial Holocene palaeo-discharges within the BB. [ABSTRACT FROM AUTHOR]

For the characterization of the viscosity and the flow behavior of heavy and extra heavy oil, a high pressure, high shear rate capillary rheometer has been developed. Due to the commercial rise in the exploitation of heavy and extra heavy oils, non-Newtonian flow behavior becomes relevant. Information on the flow properties of these heavy oils, particularly at high pressure and high shear rates is essential for recovery and processing methods. The capillary rheometer consists of two high-pressure vessels connected by a tube system including a calibrated capillary. Each vessel is equipped with a hydraulically operated metal bellow that can be varied in size to make oil flow from one vessel, through a capillary, into the other one at a controlled rate of flow. From the measured pressure drop the viscosity of Newtonian fluids is calculated with Hagen-Poiseuille's law. The capillary rheometer is designed for ambient operating conditions up to 1000 bar and 200 °C. Fluids with a viscosity between 1 and 100,000 mPas can be measured under high shear rates. The maximum possible shear rate depends on the viscosity of the fluid. For fluids with viscosities under 4000 mPas, shear rates up to 50,000 1/s are possible. Viscosities up to 100,000 mPas still allow shear rates of 4000 1/s. Before being set into operation, the apparatus is calibrated in a range up to 500 bar with viscosity standards that have been independently measured to high-pressure conditions. In this range, the apparatus works with an overall accuracy of about 3%. [ABSTRACT FROM AUTHOR]

Long-term stability and homogeneity of activity concentration in a calibration facility are vital to quality assurance and quality control for measuring thoron and its progeny. The long half-life of 212 Pb leads to difficulty for attaining highly stable activity; thus, the development of a compensation system based on air recirculation between the ageing chamber and thoron chamber is presented to make up for thoron progeny losses incurred due to plate-out, decay and sampling in the thoron chamber. Stable concentration of thoron progeny in the ageing chamber is dependent on a constant solid 220 Rn source and certain aerosol concentration. A recirculation loop with various flow-rates below 1.6 m 3 h −1 simulates air sampling of instruments being calibrated in the thoron chamber to eliminate concentration fluctuations. A theoretical model is derived for estimating the effect of main variables on the stable concentrations of 212 Pb. Variable but stable activity concentrations of 212 Pb are produced under different compensation and simulation flow-rates by this method with the coefficient of variation below 10% for the activity concentrations of thoron progeny. Concentration ratios of C( 212 Bi)/C( 212 Pb), ranging between 0.33 and 1, are achieved under different ventilation rates for the system. [ABSTRACT FROM AUTHOR]

Physically-based Li-ion electrochemical cell models have been shown capable of predicting cell performance and degradation, but are computationally expensive for optimization-oriented design applications. Faster empirical models have been developed from experimental data, but are not generalizable to operating conditions outside of the range established by the calibration data. In this paper, a reduced-order capacity-loss model for graphite anodes is derived based upon the salient physical loss mechanisms to improve computational efficiency without sacrificing model fidelity. This model captures the two primary degradation mechanisms that occur in the graphite anode of a typical lithium ion cell: a) capacity loss due to Solid Electrolyte Interface (SEI) layer growth, and b) capacity loss due to isolation of active material. The model is calibrated and validated for a commercial 2.3-Ah cell with a Lithium Iron Phosphate (LFP) cathode and graphite anode. One data set is used for calibration, another four experimental data sets are used for validation. The model matches experimental capacity degradation results within a 20% error. Moreover, the reported model is 2400× faster than currently existing more complex physically-based electrochemical models that are only slightly more accurate (in some cases). [ABSTRACT FROM AUTHOR]

The paper describes the studies on efficiency calibration and coincidence summing correction for a 3.5″×6″ cylindrical LaBr 3 (Ce)detector. GEANT4 simulations were made with point sources, namely, 60 Co, 94 Nb, 24 Na, 46 Sc and 22 Na. The simulated efficiencies, extracted using 60 Co, 94 Nb, 24 Na and 46 Sc that emit coincident gamma rays with same decay intensities, were corrected for coincidence summing by applying the method proposed by Vidmar et al. (2003). The method was applied, for the first time, for correcting the simulated efficiencies extracted using 22 Na that emits coincident gamma rays with different decay intensities. The measured results obtained using 60 Co and 22 Na were found to be in good agreement with simulated results. [ABSTRACT FROM AUTHOR]

This paper relates the calibration of a low background gas-flow proportional counter. This calibration has been used to determine low activity of 234 Th in coastal water samples. Two methods were used to prepare calibration samples: Evaporation and Electrodeposition. First method was rejected due to the lack of reproducibility because the different geometry adopted by the drops of tracer once dried on the disk. On the contrary, through the second method, similar efficiencies were obtained in all detectors with an average of 0.401±0.004. In this paper, the whole procedure to obtain 234 Th activity in dissolution as well as in particulate matter has been detailed, and all the algorithms needed to calculate activities and efficiencies are shown. Finally, two experiments have been designed in order to validate the calibration of the beta counter and the method to determine 234 Th in coastal waters with high concentration of particulate matter. [ABSTRACT FROM AUTHOR]

Indoor localization using the fingerprinting technique, namely, the radio map, has attracted much attention in the research community recently. However, constructing a complete radio map is extremely labor-extensive and time-consuming, especially for a wide area. Although some works have been done to reduce the number of calibration points, the accuracy decreases if there are not enough fingerprints. In this paper, we propose a novel method based on the radio propagation model to construct a radio map with full fingerprints. In the radio map, the calibration points (CPs), i.e., fingerprints, are classified into two categories: the primary CPs chosen to collect received signal strength (RSS) artificially, and the secondary CPs obtained through some calculations. Based on the radio map constructed, we employ the Voronoi diagram to divide the area into several Voronoi regions and restrict the localization algorithm to run in a specific Voronoi region to reduce computational complexity. The comparison results show that our method saves a lot of time and human effort in collecting RSS samples, and achieves much higher accuracy than other existing schemes. [ABSTRACT FROM AUTHOR]

Simulation of power flow in machine tools is crucial for future development of energy efficient machines as well as for energy optimization of existing machines, production systems and manufacturing processes. This paper describes analytical approach for modelling of energy consumption of auxiliary units of the CNC machine with corresponding activity management, because these units are usually not included in current models. The developed model is then compared with the measurement of the real 3-axis machine to prove the accuracy of the model. Results show the need to calibrate the real consumption of each unit instead of theoretical value from the plate of the unit. Without this calibration, models can be inaccurate. [ABSTRACT FROM AUTHOR]

Cosmic ray electrons represent a background for gamma-ray observations with Cherenkov telescopes, initiating air-showers which are difficult to distinguish from photon-initiated showers. This similarity, however, and the presence of cosmic ray electrons in every field observed, makes them potentially very useful for calibration purposes. Here we study the precision with which the relative energy scale and collection area/efficiency for photons can be established using electrons for a major next generation instrument such as CTA. We find that variations in collection efficiency on hour timescales can be corrected to better than 1%. Furthermore, the break in the electron spectrum at ∼ 0.9 TeV can be used to calibrate the energy scale at the 3% level on the same timescale. For observations on the order of hours, statistical errors become negligible below a few TeV and allow for an energy scale cross-check with instruments such as CALET and AMS. Cosmic ray electrons therefore provide a powerful calibration tool, either as an alternative to intensive atmospheric monitoring and modelling efforts, or for independent verification of such procedures. [ABSTRACT FROM AUTHOR]

Magnetic compass is widely used in the navigation system by measuring the orientation of the earth’s magnetic field and must be calibrated before used to eliminate the errors caused by the bias, misalignment, inconsistence in sensitivity, etc. In this paper, the fully digital magnetic compass was developed by using magnetic-induced magnetometers and MEMS accelerometers and the error-separation method based on a non-magnetic three-axis rotation platform was presented to calibrate the magnetic compass. The parameters about misalignment and non-orthogonality of the sensor axes and the response curve of the sensor’s output signals to earth magnetic fields were obtained. Furtherly, the sensitivity of magnetometers and the bias from the offset and hard-magnetic interference were estimated according to the response curve. The independent effect of non-orthogonality and misalignment, bias and inconsistence in sensitivity on the heading error can be evaluated with the error-separation method, respectively. After calibration, the maximum heading error of magnetic compass was about 0.4° when both pitch angle and roll angle were in the range from −60° to 60°, indicating the error-separation method is effective and efficient to calibrate magnetic compasses. [ABSTRACT FROM AUTHOR]

In order to carry out the spectral observation with the TM65m radio telescope, the frequency calibration and test of DIBAS (Digital Backend System) are performed, it is found that it has a good performance. First, by injecting the PCAL signals, the frequency resolution, frequency drift and the stability of frequency interval between two spectral lines of the DIBAS backend are measured. It is found that in one hour, the maximum frequency drift of a single spike is 0.03 channel, the maximum fluctuation of spike interval is 0.05 channel. Then, by the observations on the H 2 CO maser and absorbtion lines of massive star formation regions, and the comparison with the results observed by the GBT (Robert C. Byrd Green Bank Telescope), it is shown that the results of frequency calibration are correct. Finally, by the OH maser observations in more than one hour toward W3(OH), and the methanol maser observations in more than 5 hours, it is found that the spectral profiles keep consistent, and the observational noise is consistent with the theoretical value, indicating the stability and reliability of the frequency calibration program. [ABSTRACT FROM AUTHOR]

This paper describes the development of a new thermo-invariant material standard (new multi-feature bar (MFB) standard) and an associated procedure for the identification of 21 geometric errors on 3-axis machine tools (MT). The design of the new standard allows to extract three intrinsic parameters for each position of the MFB: 1 linear positioning error and two straightness errors. To ensure the metrology traceability chain to the SI metre definition, the calibration of the MFB is carried out using an accurate traceable coordinate measuring machine (CMM) when applying the reversal technique. The established procedure for the identification of the geometric errors was applied on a 5-axis MT, leading to the identification of the apparent 21 geometric errors of the 3 linear axes. To achieve with this purpose, the number of required positions of the MFB was optimized and reduced to only 6 positions, while using both rotary axes. The collection of raw data for each measurement was performed thanks to an accurate touch probe, linear encoders of the MT, as well as a developed interface that is independent of the industrial computer numerical control (CNC). Furthermore, the sensitivity of the geometric errors on the linear axes position is highlighted. [ABSTRACT FROM AUTHOR]

A highly sensitive and compact multi-beam angle sensor (MBAS), which utilizes the principle of operation of an autocollimator, was developed to detect the differential of the local slope components (angle difference) of a point on the mirror surface and using Fourier series, we can obtain the profile data from the angle difference. In order to investigate the application of the MBAS for high precision aspheric surface measurements, two types of calibration methods using plane mirror and cylindrical plano-convex lens has been proposed to measure the sensitivity of the MBAS. The calibration data analysis results using plane mirror agree well with the measurement results of the cylindrical plano-convex lens data. Comparison of the two methods confirms that the second method (using cylindrical plano-convex lens) is more adapted for measurement with ultra high level of uncertainty. Further, the second method is simple, corresponding to a direct calculate in the sensitive parameters aiming to minimize the cost. [ABSTRACT FROM AUTHOR]

The estimation of a mechanically affected zone (MAZ) during AFM force measurements on polymers or composites requires a precise knowledge of the probe tip geometry. A new calibration method is proposed to determine the tip geometry from force measurements on reference materials. The test is then modelled by finite element method in order to validate the probe geometry and to determine the (MAZ) on these materials. The numerical simulation is used to show the influence of test parameters and sample elastic modulus on the impacted volume. The evolution of MAZ diameter and depth with Young's modulus and sample displacement can be correctly described by two analytical models. It is then possible to predict the lateral resolution or depth penetration associated to an AFM force measurement on a given polymer. The aim is to optimize test parameters to characterize mechanical interphases at nanometre scale in multiphase materials and to measure polymer surfaces modulus in thin layer systems. [ABSTRACT FROM AUTHOR]

Frequency-domain analysis has been successfully used to (i) predict the amplification of traffic oscillations along a platoon of vehicles with nonlinear car-following laws and (ii) measure traffic oscillation properties (e.g., periodicity, magnitude) from field data. This paper proposes a new method to calibrate nonlinear car-following laws based on real-world vehicle trajectories, such that oscillation prediction (based on the calibrated car-following laws) and measurement from the same data can be compared and validated. This calibration method, for the first time, takes into account not only the driver’s car-following behavior but also the vehicle trajectory’s time-domain (e.g., location, speed) and frequency-domain properties (e.g., peak oscillation amplitude). We use Newell’s car-following model (1961) as an example and calibrate its parameters based on a penalty-based maximum likelihood estimation procedure. A series of experiments using Next Generation Simulation (NGSIM) data are conducted to illustrate the applicability and performance of the proposed approach. Results show that the calibrated car-following models are able to simultaneously reproduce observed driver behavior, time-domain trajectories, and oscillation propagation along the platoon with reasonable accuracy. [ABSTRACT FROM AUTHOR]

Summary Flow regimes (e.g., magnitude, frequency, variation, duration, timing and rating of change) play a critical role in water supply and flood control, environmental processes, as well as biodiversity and life history patterns in the aquatic ecosystem. The traditional flow magnitude-oriented calibration of hydrological model was usually inadequate to well capture all the characteristics of observed flow regimes. In this study, we simulated multiple flow regime metrics simultaneously by coupling a distributed hydrological model with an equally weighted multi-objective optimization algorithm. Two headwater watersheds in the arid Hexi Corridor were selected for the case study. Sixteen metrics were selected as optimization objectives, which could represent the major characteristics of flow regimes. Model performance was compared with that of the single objective calibration. Results showed that most metrics were better simulated by the multi-objective approach than those of the single objective calibration, especially the low and high flow magnitudes, frequency and variation, duration, maximum flow timing and rating. However, the model performance of middle flow magnitude was not significantly improved because this metric was usually well captured by single objective calibration. The timing of minimum flow was poorly predicted by both the multi-metric and single calibrations due to the uncertainties in model structure and input data. The sensitive parameter values of the hydrological model changed remarkably and the simulated hydrological processes by the multi-metric calibration became more reliable, because more flow characteristics were considered. The study is expected to provide more detailed flow information by hydrological simulation for the integrated water resources management, and to improve the simulation performances of overall flow regimes. [ABSTRACT FROM AUTHOR]

A coaxial induction probe with a vertically split outer sensor for simultaneously measuring the charge, distance, and size of a passing object is presented. When a charged sphere passed the probe, current signals of different shape induced to all the sensors. The signals were integrated, and Gaussian curves were fitted. The amplitudes and widths of the fitted curves were used to calibrate the set-up. The experimental calibration was done by using frictionally charged spheres of different sizes. Spheres with unknown size, distance, and charge were measured using the calibrated sensor. However, the speed of the object needed to be known. The results from computer simulations, calibrations, and use in measurements are presented. [ABSTRACT FROM AUTHOR]

A laser ablation ion source has been developed and implemented at the Low-Energy Beam and Ion Trap (LEBIT) facility at the National Superconducting Cyclotron Laboratory. This offline ion source enhances the capabilities of LEBIT by providing increased access to ions used for calibration measurements and checks of systematic effects as well as stable and long-lived ions of scientific interest. The design of the laser ablation ion source and a demonstration of its successful operation are presented. [ABSTRACT FROM AUTHOR]

Tensile strain penetration effects have been first investigated in the study of reinforced concrete components as experimental studies highlighted that theoretical values for the equivalent plastic hinge length did not reflect the observed experimental results. This is due to the elongation of the bars beyond the theoretical interface of the structural element with another component (e.g. beam-to-column or column/wall-to-foundation connections). The concept of an equivalent strain penetration length was first introduced for flexural analysis of concrete elements and the definition of the element’s plastic hinge length. Experimentally calibrated expressions for the equivalent strain penetration length have been developed in literature and extensively adopted in the design of traditional reinforced concrete connections. Internal partially unbonded bars have more recently been used is precast concrete dissipative post-tensioned rocking systems, developed during the PREcast Seismic Structural Systems (PRESSS) program, and more recently in timber rocking (Pres-Lam). As per bars embedded or post-grouted into concrete, internally glued bars in timber are affected by tensile strain penetration effects. An important parameter involved in the design of dissipative rocking section as well as more traditional epoxied rods connections is the additional slip and consequent loss of stiffness, strength and energy dissipation due to strain penetration. The paper shows the determination of an equivalent strain penetration length in internal epoxied bars through the experimental testing of several specimens accounting for different geometric parameters. The final part of the paper discussed the experimental results in terms of bar slip proposing simplified analytical formulas. [ABSTRACT FROM AUTHOR]

Bayesian computation has received increasing attention in calibrating building energy models due to its flexibility and accuracy. However, there has been little research on how to determine informative energy data in Bayesian calibration in building energy models. Therefore, this study aims to determine and choose informative energy data using correlation analysis and hierarchical clustering method. A case study of retail building is used to demonstrate the proposed methods to infer four unknown input parameters using EnergyPlus program. The results indicate that the different combinations of energy data can provide various levels of accuracy in estimating unknown input variables in model calibration. This suggests that Bayesian computation is suitable for inferring the parameters when there are missing energy data that can be treated as uninformative output data. The proposed method can be also used to find the redundant information on energy data in order to improve computational efficiency in Bayesian calibration. [ABSTRACT FROM AUTHOR]

A novel approach for the resolution and quantitation of severely overlapped quaternary mixture of carbinoxamine maleate (CAR), pholcodine (PHL), ephedrine hydrochloride (EPH) and sunset yellow (SUN) in syrup was demonstrated utilizing different spectrophotometric assisted multivariate calibration methods. The applied methods have used different processing and pre-processing algorithms. The proposed methods were partial least squares (PLS), concentration residuals augmented classical least squares (CRACLS), and a novel method; continuous wavelet transforms coupled with partial least squares (CWT-PLS). These methods were applied to a training set in the concentration ranges of 40–100 μg/mL, 40–160 μg/mL, 100–500 μg/mL and 8–24 μg/mL for the four components, respectively. The utilized methods have not required any preliminary separation step or chemical pretreatment. The validity of the methods was evaluated by an external validation set. The selectivity of the developed methods was demonstrated by analyzing the drugs in their combined pharmaceutical formulation without any interference from additives. The obtained results were statistically compared with the official and reported methods where no significant difference was observed regarding both accuracy and precision. [ABSTRACT FROM AUTHOR]

Atomic Force Microscopy (AFM) has been widely used for measuring friction force at the nano-scale. However, one of the key challenges faced by AFM researchers is to calibrate an AFM system to interpret a lateral force signal as a quantifiable force. In this study, five rectangular cantilevers were used to quantitatively compare three different lateral force calibration methods to demonstrate the legitimacy and to establish confidence in the quantitative integrity of the proposed methods. The Flat-Wedge method is based on a variation of the lateral output on a surface with flat and changing slopes, the Multi-Load Pivot method is based on taking pivot measurements at several locations along the cantilever length, and the Lateral AFM Thermal-Sader method is based on determining the optical lever sensitivity from the thermal noise spectrum of the first torsional mode with a known torsional spring constant from the Sader method. The results of the calibration using the Flat-Wedge and Multi-Load Pivot methods were found to be consistent within experimental uncertainties, and the experimental uncertainties of the two methods were found to be less than 15%. However, the lateral force sensitivity determined by the Lateral AFM Thermal-Sader method was found to be 8–29% smaller than those obtained from the other two methods. This discrepancy decreased to 3–19% when the torsional mode correction factor for an ideal cantilever was used, which suggests that the torsional mode correction should be taken into account to establish confidence in Lateral AFM Thermal-Sader method. [ABSTRACT FROM AUTHOR]

Structured light (SL) methods are widely used in 3D measurement systems because of their speed and contactless operation. These methods provide high resolution 3D modeling. Phase shifting is one of the SL algorithms that give high resolution with less number of pattern requirements. Since reflected patterns and obtained results are commonly distorted due to the lenses in cameras and projector systems, system calibration must be fulfilled before starting 3D modeling with SL system. Uncalibrated SL system may model the object much greater/smaller than the real dimension of it. In this study, a three step calibration system is proposed for an SL system that uses a three phase shifting algorithm with automatic thresholding. These calibration steps include camera calibration, projector calibration and depth calibration. Experimental studies showed that proposed calibrated system reduces the camera and projector lens errors. Depth calibration is applied as a last calibration step provided a 3D modeling of the object with accurate dimension. Dimensions of the objects and their 3D models are compared to have accuracy of the proposed 3D modeling system. After system calibration, obtained results showed that proposed 3D modeling system gives high accuracy with acceptable depth measurements. [ABSTRACT FROM AUTHOR]

The paper discusses thermal transient measurements of advanced devices which operate in a temperature range where linearity cannot be assumed. However, finding a proper physical equation; valid on a wide temperature range for a device category; their calibration can be carried out at convenient temperatures. The validity of the technique can be verified by the good fit of calibrated transients at different power. Some high frequency devices have only a single known stable operation point; the validity of the measurements can be verified by comparing transients of different lengths. In the paper measurements of a device on the R DSON parameter and on reverse diode were compared. Thermal calibration of the R DSON parameter of a FET gives a methodology for measuring the μ n electron mobility. An extension to existing transient standards is suggested. For a more accurate definition of the junction temperature a non-isothermal calculation methodology is outlined. [ABSTRACT FROM AUTHOR]

Single standard to determine multi-components (SSDMC) is a practical pattern for quality evaluation of herbal medicines (HMs). However, it remains challenging because of potential inconsistency of relative response factors (RRF) on different instruments. In this work, the effects of two key roles, i.e., ultraviolet (UV) wavelength and standard solution concentrations, on reproducibility of RRF were investigated. The effect of UV wavelength on reproducibility of RRF was studied by plotting the relationship of the peak area ratios (internal standard vs analyte) to wavelengths. The preferable wavelength should be set at the flat parts of the curve. Optimized 300 nm produced a 0.38% RSD for emodin/emodin-8- O -β- D -glucopyranoside on five instruments, much lower than 2.80% obtained from the maximum wavelength at 290 nm. Next, the effects of standard solution concentrations of emodin on its response factor (RF) were investigated. For one single point method, low concentration less than 49b/k resulted in significant variations in RF. For emodin, when the concentration is higher than 7.00 μg mL −1 , a low standard deviation (SD) value at 0.13 was obtained, while lower than 7.00 μg mL −1 , a high SD at 3.71 was obtained. The developed SSDMC method was then applied to determination of target components in 10 Polygonum cuspidatum samples and showed comparable accuracy to conventional calibration methods with deviation less than 1%. [ABSTRACT FROM AUTHOR]

This paper presents a way to implement a test structure able to measure accurately a large number of threshold voltage values for Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) matching characterization. A multiplexed system able to select a single transistor among others in a small array is used. This architecture guarantees a similar environment for all transistors in the array, while requiring a small number of pads for measurement. Moreover, the influence of the multiplexer switches can be evaluated: their unwanted contribution to the measurement can therefore be compensated. An experimental study to evaluate the influence of this multiplexer on measurement and the efficiency of the compensation is conducted. Silicon results are presented in order to validate the concept. [ABSTRACT FROM AUTHOR]

A generalized reduced order model for resonant viscosity and mass density sensors is presented and experimentally verified. The reduced expressions for the resonance frequency and quality factor, respectively, are mathematically valid for in-plane oscillating plates, oscillating spheres and laterally oscillating cylinders. However, as shown for measurements obtained with a tuning fork resonator with rectangular cross-section, the model can also be applied for resonating structures, for which closed form solutions of the fluid structure interaction are not available. Benefits of the presented model are amongst others first, its simplicity, which requires no more than three calibration measurements for parameter identification and second, its general applicability for resonant mass density and viscosity sensors which furthermore facilitates the comparison of different resonant mass density and viscosity sensors in terms of sensitivity and measurement noise propagation. [ABSTRACT FROM AUTHOR]