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The automation of the engineering procedure of calibrating instrumentation by introducing digital technology of computer vision into the production process is assessed. Optimization of the production process by means of digital technology of computer vision eliminates the adverse effect of some errors and, by reducing the time spent on certification, diminishes the impact of high-temperature processes on measuring equipment. An operational characteristic of calibration is developed taking into account subjective errors, such as the interpolation and parallax errors, which occur if testing is carried out by an operator. The determined dependence is compared with the plot based on the calibration indicators in introducing computer vision technology into the production process. [ABSTRACT FROM AUTHOR]

In order to ensure the measurement accuracy of high-acceleration vibration sensors used in engineering applications, it is necessary to calibrate their key performance parameters at high acceleration. The high-acceleration vibration calibration system produces high-acceleration vibration by utilizing the resonance amplification principle; however, the resonance frequency of the resonant beam changes with increasing amplitude, affected by the influences of nonlinear and other factors. In this study, a phase-locked resonance tracking control method based on the phase resonance principle is proposed to accurately and quickly track the resonance frequency of the resonant beam, which can improve the accuracy and stability of resonance control. The resonant beam is able to produce stable vibration with an amplitude exceeding 7500 m/s2 by phase-locking and tracking the resonant frequency. A calibration system built with this method can provide stable vibration with an amplitude of 500–10,000 m/s2 in the range of 80–4000 Hz. Comparison experiments with the commonly used amplitude iteration amplification method demonstrate that the proposed method can give an acceleration stability control index of less than 0.5% and a resonance tracking time of less than 0.1 s. [ABSTRACT FROM AUTHOR]

The secondary outfitting work of the immersed tube needs to be carried out in a floating state. The measuring tower is an important outfitting part in the secondary outfitting. Its calibration of the precise position of pipe sections is related to the success of the floating installation of the immersed tube. Since the pipe sections are floating on the sea surface, it poses a huge challenge to the calibration of the measuring tower. In this paper, the calibration methods of measuring towers in the floating state of five pipe sections were introduced, and their advantages and disadvantages were analyzed, and the calibration methods used in the Dalian Bay subsea tunnel project were analyzed. The results show that the accuracy of the GNSS synchronization calibration method can reach 2 cm on the plane, and that of total station floating calibration method can reach 1 cm on the plane, which meets engineering needs. The results can provide reference for other similar marine engineering calibration measurements. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical and experimental analysis of an anomalous data detection treatment for roller-integrated compaction measurement (RICM) data. Anomalous data, which may be discovered during the collection of the RICM data, can significantly influence the evaluation of the compaction quality and misrepresent the real compaction situation of the layer. Two types of anomalous data are investigated, and corresponding methods are presented to identify these types. A bidimensional anomalous data identification method is proposed to distinguish anomalous data in calibration tests, and a neighboring weighted-estimation method is presented to reject anomalous data during the compaction quality assessment. The RICM data from three field construction sites are analyzed to verify the applicability and validity of the proposed methods. The results suggest that the first method renders a more accurate correlation, whereas the second method improves the precision of the compaction evaluation. [ABSTRACT FROM AUTHOR]

In order to set integrated procedures involving geotechnical and structural aspects finalized to buildings diagnostics, uncertainty aspects are discussed concerning three-axis accelerometers and inclinometers for a distributed sensor network. This network allows to operate in a selective manner, preferring the most critical situations. To this aim, the main aspects affecting the measurement uncertainty of sensors to be used for building diagnostic should be known. As the firstly step of the uncertainty evaluation procedure, we focused on the calibration of sensors used for the task. The requirement of low cost and complexity of sensors and test benches was considered. Experimental results show that satisfactory calibration accuracy could be achieved, also for the low frequency range, 0–10 Hz. Systematic errors are minimized and main parameters affecting uncertainty are identified, such as: the motion positioning of the accelerometer with respect to the vertical axis, the imposed motion law, the parameter used as the reference and, finally, the real radial positioning of the sensor. Requirements to be satisfied by the sensor are also analysed. [ABSTRACT FROM AUTHOR]

Virtual testing is a recent engineering development trend to design, evaluate, and test new engineered products. This research proposes a framework of virtual testing based on statistical inference for new product development comprising of three successive steps: (i) statistical model calibration, (ii) hypothesis test for validity check and (iii) virtual qualification. Statistical model calibration first improves the predictive capability of a computational model in a calibration domain. Next, the hypothesis test is performed with limited observed data to see if a calibrated model is sufficiently predictive for virtual testing of a new product design. An area metric and the u-pooling method are employed for the hypothesis test to measure the degree of mismatch between predicted and observed results while considering statistical uncertainty in the area metric due to the lack of experimental data. Once the calibrated model becomes valid, the virtual qualification process can be executed with a qualified model for new product developments. The qualification process builds a design decision matrix to aid in rational decision-making for product design alternatives. The effectiveness of the proposed framework is demonstrated through the case study of a tire tread block. [ABSTRACT FROM AUTHOR]

The Thermal Infrared Sensor (TIRS) on Landsat 8 is the latest thermal sensor in that series of missions. Unlike the previous single-channel sensors, TIRS uses two channels to cover the 10-12.5 micron band. It is also a pushbroom imager; a departure from the previous whiskbroom approach. Nevertheless, the instrument requirements are defined such that data continuity is maintained. This paper describes the design of the TIRS instrument, the results of pre-launch calibration measurements and shows an example of initial on-orbit science performance compared to Landsat 7. [ABSTRACT FROM AUTHOR]

An AC shunt calibration system using a current-bridge method is developed, and its measurement uncertainties are estimated. A comparison of the calibration results obtained using the current-bridge method with the results using DC resistance and AC-DC difference methods was performed to verify the system. These comparison results show that the current-bridge-based system performs well with small measurement uncertainties for both the AC resistance and phase angle of the AC shunts up to 1 kHz. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

The capability to calibrate diagnostics, such as the Motional Stark Effect (MSE) diagnostic, without using plasma or beam-into-gas discharges will become increasingly important on next step fusion facilities due to machine availability and operational constraints. A robotic calibration system consisting of a motorized three-axis positioning system and a polarization light source capable of generating arbitrary polarization states with a linear polarization angle accuracy of <0.05° has been constructed and has been used to calibrate the MSE diagnostic deployed on Alcator C-Mod. The polarization response of the complex diagnostic is shown to be fully captured using a Fourier expansion of the detector signals in terms of even harmonics of the input polarization angle. The system's high precision robotic control of position and orientation allow it to be used also to calibrate the geometry of the instrument's view. Combined with careful measurements of the narrow bandpass spectral filters, this system fully calibrates the diagnostic without any plasma discharges. The system's high repeatability, flexibility, and speed has been exploited to quantify several systematics in the MSE diagnostic response, providing a more complete understanding of the diagnostic performance. [ABSTRACT FROM AUTHOR]

Many of the masonry arch bridges in the network of railway bridge stock belong to the civil engineering heritage of the railways. Therefore, their maintenance and management require careful consideration. An effective procedure for performance evaluation should promote solutions that are directed toward preservation and restoration of arch bridges by evaluating their existing structural capacity. In this paper, experimental methodologies adopted for the performance evaluation of a stone masonry-arch railway bridge are presented. One of the primary objectives of the current study was to evaluate the longitudinal force exerted on the bridge due to increased axle loads of freight wagons. An innovative technique using a flat jack was implemented for the evaluation of longitudinal stress due to increased axle load. Three-dimensional numerical modeling and analysis was carried out to identify the critical locations for fixing the flat jacks for evaluation of live-load stresses. A special instrumentation scheme with which very low strain can be measured was adopted for the evaluation of pier strains. From the field study, the maximum deflection under dynamic test conditions was found to be 0.465 mm and this is within the permissible limit. From the dynamic response measured using the flat jack, the maximum longitudinal stress in the arch due to tractive effort was approximately 0.3 MPa. It has been evaluated that the maximum longitudinal force (per rail) at rail level is 12.31T in the instrumented span. The responses measured from the bridge are within permissible limits. The methodology developed and implemented for the performance evaluation of arch bridges would pave the way for undertaking better and timely maintenance strategies. [ABSTRACT FROM AUTHOR]

Brain-machine interface (BMI) systems give users direct neural control of robotic, communication, or functional electrical stimulation systems. As BMI systems begin transitioning from laboratory settings into activities of daily living, an important goal is to develop neural decoding algorithms that can be calibrated with a minimal burden on the user, provide stable control for long periods of time, and can be responsive to fluctuations in the decoder’s neural input space (e.g. neurons appearing or being lost amongst electrode recordings). These are significant challenges for static neural decoding algorithms that assume stationary input/output relationships. Here we use an actor-critic reinforcement learning architecture to provide an adaptive BMI controller that can successfully adapt to dramatic neural reorganizations, can maintain its performance over long time periods, and which does not require the user to produce specific kinetic or kinematic activities to calibrate the BMI. Two marmoset monkeys used the Reinforcement Learning BMI (RLBMI) to successfully control a robotic arm during a two-target reaching task. The RLBMI was initialized using random initial conditions, and it quickly learned to control the robot from brain states using only a binary evaluative feedback regarding whether previously chosen robot actions were good or bad. The RLBMI was able to maintain control over the system throughout sessions spanning multiple weeks. Furthermore, the RLBMI was able to quickly adapt and maintain control of the robot despite dramatic perturbations to the neural inputs, including a series of tests in which the neuron input space was deliberately halved or doubled. [ABSTRACT FROM AUTHOR]

ABSTRACT To accurately perform the fatigue assessment of engineering components subjected to in-service multiaxial fatigue loading, the adopted design criterion must properly be calibrated, the used information usually being the fatigue strength under both pure uniaxial and pure torsional fatigue loading. Because of the complex fatigue response of metallic materials to multiaxial loading paths, the only reliable way to generate the necessary pieces of calibration information is by running appropriate experiments. Unfortunately, because of a lack of both time and resources, very often, structural engineers are requested to perform the multiaxial fatigue assessment by guessing the necessary fatigue properties. In this complex scenario, initially, the available empirical rules suitable for estimating fatigue strength under both pure axial and pure torsional fatigue loading are reviewed in detail. Subsequently, several experimental results taken from the literature and generated by testing metallic materials under a variety of proportional and non-proportional multiaxial loading paths are used to investigate the way such empirical rules affect the accuracy in estimating fatigue strength, the damage extent being evaluated according to the modified Wöhler curve method. Such a systematic validation exercise allowed us to prove that under proportional loading (with both zero and non-zero mean stresses), an adequate margin of safety can be reached even when the necessary calibration information is directly estimated from the material ultimate tensile strength. On the contrary, in the presence of non-proportional loading, the use of the empirical rules reviewed in the present paper can result, under particular circumstances, in a non-conservative fatigue design. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the results of an experimental program developed to study the feasibility of producing prestressed concrete girders using lightweight concrete. During the experimental campaign, bond tests were performed in push-in (TL bond test) and pull-out (FB bond test) types of specimens. To-scale prestressed concrete elements were produced, implemented, and tested. The variables studied were the type of concrete, the test age, and the delayed effects of bond. The TL bond test allowed the behavior of the transfer length to be characterized, governed by the Hoyer effect. Equations have been calibrated to identify the upper and lower transfer lengths using the experimental results of this trial. The proposed equations delimit the safety boundaries of the experimental transfer length values obtained in the experiments performed on the beams. The results obtained in the experimental phase discourage the use of the studied lightweight concrete for producing pre-tensioned concrete elements. [Copyright &y& Elsevier]

A multi-centre trial using PET requires the analysis of images acquired on different systems We designed a multi-centre trial to estimate the value of 18F-FLT-PET to predict response to neoadjuvant chemotherapy in patients with newly diagnosed breast cancer. A calibration check of each PET-CT and of its peripheral devices was performed to evaluate the reliability of the results. Material and Methods: 11 centres were investigated. Dose calibrators were assessed by repeated measurements of a 68Ge certified source. The differences between the clocks associated with the dose calibrators and inherent to the PET systems were registered. The calibration of PET-CT was assessed with an homogeneous cylindrical phantom by comparing the activities per unit of volume calculated from the dose calibrator measurements with that measured on 15 Regions of Interest (ROIs) drawn on 15 consecutive slices of reconstructed filtered back-projection (FBP) images. Both repeatability of activity concentration based upon the 15 ROIs (ANOVA-test) and its accuracy were evaluated. Results: There was no significant difference for dose calibrator measurements (median of difference −0.04%; min = −4.65%; max = +5.63%). Mismatches between the clocks were less than 2 min in all sites and thus did not require any correction, regarding the half life of 18F. For all the PET systems, ANOVA revealed no significant difference between the activity concentrations estimated from the 15 ROIs (median of difference −0.69%; min = −9.97%; max = +9.60%). Conclusion: No major difference between the 11 centres with respect to calibration and cross-calibration was observed. The reliability of our 18F-FLT multi-centre clinical trial was therefore confirmed from the physical point of view. This type of procedure may be useful for any clinical trial involving different PET systems. [ABSTRACT FROM AUTHOR]

The relationship between biomechanical action and perception of self-motion during walking is typically consistent and well-learned but also adaptable. This perceptual-motor coupling can be recalibrated by creating a mismatch between the visual information for self-motion and walking speed. Perceptual-motor recalibration of locomotion has been demonstrated through effects on subsequent walking without vision, showing that learned perceptual-motor coupling influences a dynamic representation of one's spatial position during walking. Our present studies test whether recalibration of wheelchair locomotion, a novel form of locomotion for typically walking individuals, similarly influences subsequent wheelchair locomotion. Furthermore, we test whether adaptation to the pairing of visual information for self-motion during one form of locomotion transfers to a different locomotion modality. We find strong effects of perceptual-motor recalibration for matched locomotion modalities – walking/walking and wheeling/wheeling. Transfer across incongruent locomotion modalities showed weak recalibration effects. The results have implications both for theories of perceptual-motor calibration mechanisms and their effects on spatial orientation, as well as for practical applications in training and rehabilitation. [ABSTRACT FROM AUTHOR]

This paper reviews and analyzes studies concerning measurement uncertainty, examining 114 papers published between 2004 and 2010 in the following international journals: IEEE Transactions on Instrumentation and Measurement, Measurement, Flow Measurement and Instrumentation, and Precision Engineering. The papers were classified according to six different approaches identified during the research and six different methods of calculating uncertainty used by the authors of the researched articles. This paper provides a short summary of the state of the art of measurement uncertainty, analyzes the research scenario on the theme, and, finally, brings suggestions on future work based on the analysis. [ABSTRACT FROM AUTHOR]

Analysis and forecasting were made in this paper aiming at the problem of top pressure of coke tower of 1200 x 10³ t/a delayed coking unit in the refinery of Daqing Petrochemical Company rises continuously causing by volaile lines coking. Various operation conditions of the unit are alibrated, the results show that the higher the furnace outet temperature, the smaller processing capacity of the unit, After taking a series of measures such as stopping blending with FCC slurry oil, injecting defoamer and so on, the height of foam layer in coke tower was decreased so as to low down the coking rate of the volatile lines, which provides a strong guarantee for long-term operation of the unit. [ABSTRACT FROM AUTHOR]

Abstract: Regime switching volatility models provide a tractable method of modelling stochastic volatility. Currently the most popular method of regime switching calibration is the Hamilton filter. We propose using the Baum–Welch algorithm, an established technique from Engineering, to calibrate regime switching models instead. We demonstrate the Baum–Welch algorithm and discuss the significant advantages that it provides compared to the Hamilton filter. We provide computational results of calibrating and comparing the performance of the Baum–Welch and the Hamilton filter to S&P 500 and Nikkei 225 data, examining their performance in and out of sample. [Copyright &y& Elsevier]

A numerical model for the loose and the cemented component of the Torino subsoil is presented in this paper. The model is represented by a dense packing of nonuniform sized cylindrical particles with clumps by using the particle flow code in two dimensions. The paper shows how the synthetic specimens were calibrated to reproduce true material behavior giving insights over the influence of various parameters (such as platens velocity, particle shape, bond strength, etc.) on the mechanical behavior of bonded and unbonded assemblies. Loose and cemented ground are basically characterized by the same grain-size distribution, therefore the same numerical model is adopted. The effect of cementation is taken into account by introducing parallel bonds at contacts between the different particles. It is shown that the mechanical behavior of the Torino subsoil is well reproduced at the volume element scale. The results can be used to build representative numerical models to study engineering problems at the site scale. [ABSTRACT FROM AUTHOR]

Objectives: Calibrating a disease simulation model's outputs to existing clinical data is vital to generate confidence in the model's predictive ability. Calibration involves two challenges: 1) defining a total goodness-of-fit ( GOF) score for multiple targets if simultaneous fitting is required, and 2) searching for the optimal parameter set that minimizes the total GOF score (i.e., yields the best fit). To address these two prominent challenges, we have applied an engineering approach to calibrate a microsimulation model, the Lung Cancer Policy Model (LCPM). Methods: First, 11 targets derived from clinical and epidemiologic data were combined into a total GOF score by a weighted-sum approach, accounting for the user-defined relative importance of the calibration targets. Second, two automated parameter search algorithms, simulated annealing (SA) and genetic algorithm (GA), were independently applied to a simultaneous search of 28 natural history parameters to minimize the total GOF score. Algorithm performance metrics were defined for speed and model fit. Results: Both search algorithms obtained total GOF scores below 95 within 1000 search iterations. Our results show that SA outperformed GA in locating a lower GOF. After calibrating our LCPM, the predicted natural history of lung cancer was consistent with other mathematical models of lung cancer development. Conclusion: An engineering-based calibration method was able to simultaneously fit LCPM output to multiple calibration targets, with the benefits of fast computational speed and reduced the need for human input and its potential bias. [ABSTRACT FROM AUTHOR]

This paper describes the implementation of a new quantum-based system for the generation of 120 V RMS, 5 A RMS, sinusoidal, active, and reactive power over the 50 to 400 Hz frequency range. The system accurately relates the spectral amplitudes and phases of the voltage and current waveforms of the generated power to a programmable Josephson voltage standard (PJVS) by using a novel differential sampling technique. The system also employs a new voltage amplifier that performs self-calibration and corrections of the gain and phase errors. Details of the system design, measurement techniques, and significant sources of error are presented. [ABSTRACT FROM AUTHOR]

This paper describes how to calibrate a four- terminal-pair (4TP) LCR meter at the right (90°) angle. The LCR meter uses the right angle signal to process a synchronous detector as a vector signal receiver. The right-angle calibration method uses, at a minimum, one variable-phase signal generator (SG) and a phase shift circuit. The SG does not require a precision right angle, but it does need good phase stability. The described phase shifter provides the required differential phase of nearly the right angle. As a result, the right-angle phase deviation of the LCR meter is better than 65 μrad (0.223′) with 37-μrad (0.127′) uncertainty at 10 MHz. This method is also applicable to the phase calibration of a vector network analyzer. [ABSTRACT FROM AUTHOR]

An algorithm is examined for recognizing measurement markers of various application, which are used in three-dimensional information and measurement systems. Examples are presented for using the algorithm in systems based on photogrammetry technology. [ABSTRACT FROM AUTHOR]

The spectral stiffness microplane (SSM) model developed in the preceding Part I of this study is verified by comparisons with experimental data for uniaxial and biaxial tests of unidirectional and multidirectional laminates. The model is calibrated by simulating the experimental data on failure stress envelopes analyzed in the recent so-called "World Wide Failure Exercise," in which various existing theories were compared. The present theory fits the experiments as well as the theories that were best in the exercise. In addition, it can simulate the post-peak softening behavior and fracture, which is important for evaluating the energy-dissipation capability of composite laminate structures. The post-peak softening behavior and fracture are simulated by means of the crack band approach which involves a material characteristic length. [ABSTRACT FROM AUTHOR]

In our days precise geodetic instruments are very widely used in geodesy, building structures, surveying, machine engineering etc. Many of those instruments are based on precise measurement of the directions differences (ie measurement of angles). Such instruments are: theodolites, digital theodolites, total stations etc. Testing and calibration of these instruments is quite complicated task, although it is evidently needed. In this paper we present the creation and preliminary research of accuracy of the test bench designed to perform the testing and calibration of such geodetic instruments. [ABSTRACT FROM AUTHOR]

Abstract: Accurate global solar radiation measurements are crucial to climate change research and the development of solar energy technologies. Pyranometers produce an electrical signal proportional to global irradiance. The signal-to-irradiance ratio is the responsivity (RS) of the instrument (RS=signal/irradiance=microvolts/(W/m2)). Most engineering measurements are made using a constant RS. It is known that RS varies with day of year, zenith angle, and net infrared radiation. This study proposes a method to find an RS function to model a pyranometer’s changing RS. Using a reference irradiance calculated from direct and diffuse instruments, we found instantaneous RS for two global pyranometers over 31 sunny days in a two-year period. We performed successive independent regressions of the error between the constant and instantaneous RS with respect to zenith angle, day of year, and net infrared to obtain an RS function. An alternative method replaced the infrared regression with an independently developed technique to account for thermal offset. Results show improved uncertainties with the function method than with the single-calibration value. Lower uncertainties also occur using a black-and-white (8-48), rather than all-black (PSP), shaded pyranometer as the diffuse reference instrument. We conclude that the function method is extremely effective in reducing uncertainty in the irradiance measurements for global PSP pyranometers if they are calibrated at the deployment site. Furthermore, it was found that the function method accounts for the pyranometer’s thermal offset, rendering further corrections unnecessary. The improvements in irradiance data achieved in this study will serve to increase the accuracy of solar energy assessments and atmospheric research. [Copyright &y& Elsevier]

In November 2000 a landslide–debris flow with a volume of 1.2×106 m3 slid down from Stozˇe Mountain in NW Slovenia. It partly or totally destroyed 23 buildings in the village of Log pod Mangartom and killed 7 people. As landslides of the same or even greater initial mass could endanger the village in the future, numerical simulations of these possible events were carried out. A hazard map of the area, and the most effective protection measures were determined in detail. A one-dimensional model DEBRIF1D, developed from a dam-break flow model, was used for simulations along the canyon in the upper part of the reach. Downstream, in the region of the village, two two-dimensional models were used: a newly developed PCFLOW2D, and a commercial model FLO-2D. The three models were calibrated by field measurements. A special feature of the DEBRIF1D model enables direct computation of the initial hydrograph. Validity of the quadratic equation expressing the resistance was roughly confirmed by field measurements, and a comparison of the accuracy and applicability of the three models is given. [ABSTRACT FROM AUTHOR]

Abstract: To meet the demand of measuring the complex prototypes completely in reverse engineering, a multi-probe measurement system integrated with a coordinate measuring machine (CMM), a structured-light sensor, a trigger probe and a rotary table is presented in this paper. The structured-light sensor is designed with optimal structure, and its model is established based on the CMM to simplify its parameters, this enables the sensor to be calibrated expediently at any condition. Three measuring modes are proposed considering the efficiency of the structured-light sensor, the high accuracy and flexibility of the trigger probe and the rotation of the table for finding proper scanning views. The structured-light sensor is usually applied to scan the profile of a part from different views, while the trigger probe is used to measure the edge and key features of the part. The data generated by different modes can be merged into a whole data body. The system possesses the function of obtaining the coordinate of nearly any point on a complicated part. Experiment studies on the accuracy of the structured-light sensor, data patch assembling and data merging show that the total accuracy of the system is ±0.033mm. [Copyright &y& Elsevier]

This paper presents a solution to the problem of tracking intermittent targets that can overcome long-term occlusions, as well as movement between camera views. Unlike other approaches, our system does not require topological knowledge of the site or labelled training patterns during the learning period. The approach uses the statistical consistency of data obtained automatically over an extended period of time rather than explicit geometric calibration to automatically learn the salient reappearance periods for objects. This allows us to predict where objects may reappear, and within how long. We demonstrate how these salient reappearance periods can be used with a model of physical appearance to track objects between spatially separate regions in single and separated views. [ABSTRACT FROM AUTHOR]

The article presents information on adjusting software failure rates that are estimated from test data. An estimate of the user-perceived failure rate of software is essential for deciding when to deploy the software while maintaining an appropriate balance between reliability, time-to-market, and development cost. Typically, software reliability models are applied to test data with the hope of obtaining a credible estimate of the software failure rate that will be observed in the field. This article extends an empirical calibration methodology for adjusting the failure rate estimate obtained from analysing test data.

Precise heighting by the hidden point bar method is investigated. The investigation includes development of the mathematical model, calibration of the hidden point bar, and comparison with precise leveling and precise trig heighting. The method is applied in the field at a coal-fired electric power generating plan. Both the field application and the comparison with precise leveling and precise trig heighting indicated that the level of precision is on the order of 0.1 mm. Special advantages of the method are that the target point does not have to be visible from the measurement instrument and the bar placed on the target can be set at any convenient orientation. [ABSTRACT FROM AUTHOR]

Explores the standards concerning vibration calibration. Revisions made on the standards related to the calibration of vibration and shock transducers; Upgrades made for sine calibration of vibration sensors and methods for the calibration of shock transducers by shock excitation; Requirements for obtaining low uncertainties in calibration.

A procedure of testing sensors for compliance with the metrological requirements immediately on the plant in the course of operation was proposed. It is based on using the predefined calibration characteristics and main errors for various values of the influencing factors, generating a reference signal in the course of diagnosis, measuring the affecting factors, and comparing the sensor readings with the values obtained at calibration. A diagnostic procedure for the cases where determination of the reference signal is hindered was considered. Feasibility of diagnosis without generating the reference signal was exemplified by the radio-frequency sensors. [ABSTRACT FROM AUTHOR]

The ISO “Guide to the Expression of Uncertainty in Measurement” (GUM) establishes a unified method for evaluating and stating measurement uncertainties that has been accepted by nearly all calibration services and most test co-operations in all parts of the world. In measurements of mechanical quantities, such as acceleration and derived motion quantities, the application of the GUM may be difficult and very time-consuming unless some possibilities of simplification are made use of. After a brief introduction to the basic procedure specified in the GUM for the calculation of the measurement uncertainty, a survey of the problems typically encountered in uncertainty calculations when, for example, vibrations are measured or accelerometers calibrated by laser interferometry is given. It is shown how a model function of simple structure can be established for the usually complex relationship between the output quantity (e.g. sensitivity of an accelerometer), the quantity to be measured (e.g. acceleration) and various influence quantities (noise, transverse motion, base strain, etc.). Among other things, non-linear effects such as the influences of distortion, hum and noise can be properly taken into account. [Copyright &y& Elsevier]

Presents a study which examines a class of stochastic models for the evaluation of the optimal calibration interval in measuring instruments. Assumption that the calibration status of a measuring instrument can be monitored by one observable parameter.

Presents a study which demonstrates a thru-match-reflect/line-match-reflect (TMR/LMR) self-calibration procedure, which is based on the 16-term error model. Presentation of simple closed-form calibration equations; Calibration comprised of two-port measurement.

• Modeling and simulation are key tools to optimizing systems prior to prototyping. • Simulating a model with sophisticated sampling methods characterize the trade space. • Design of experiments support model verification and surrogate modeling. • Surrogate models provide a rapid trade space exploration tool. • DOE-based M&S surrogates support model calibration and validation with test data. Modern computing resources provide scientists, engineers, and system design teams the ability to study phenomena, such as system behavior, in a virtual setting. Computational modeling and simulation (M&S) enables engineers to avoid many of the challenges encountered in traditional design engineering, including the design, manufacture, and testing of expensive prototypes prior to having an optimized design. However, the use of M&S carries its own challenges, such as the computational time and resources required to execute effective studies, and uncertainties arising from simplifying assumptions inherent to computer models, which are intended to be an approximate representation of reality. In recent year advances have been made in a number of areas related to the efficient and reliable use of M&S for system evaluations, including design & analysis of computer experiments, uncertainty quantification, probabilistic analysis, response optimization, and data synthesis techniques. In this review paper, a general framework for systematically executing efficient M&S studies at the component-level, product-level, system-level, and system-of-systems-level is described. A case study is used to demonstrate how statistical and probabilistic techniques can be integrated with M&S to address those challenges inherent to model-based engineering, and how this aligns with the proposed workflow. The example is a gun-launch dynamics model of an artillery projectile developed by US Army engineers, and illustrates the application of this workflow in the study of subsystem system reliability, performance, and end-to-end system-level characterization. [ABSTRACT FROM AUTHOR]

As a new visualization method, calibration-free augmented reality based on vision is presented. It is convenient to apply this method to civil engineering. The main ideas of this method and an application example are given in this paper. Its application is successful.Key words: visualization, augmented reality, virtual reality, affine representation, vision.En tant que nouvelle méthode de visualisation, la réalité améliorée, sans calibration, basée sur la vision, est présentée. Elle s'applique aisément en génie civil. Les concepts généraux de cette méthode et un cas d'application sont donnés dans cet article. Son application s'avère être un succès.Mots clés : visualisation, réalité améliorée, réalité virtuelle, représentation affine, vision.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]