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Traditional technologies for solving hand-eye calibration and inverse kinematics are cumbersome and time consuming due to the high nonlinearity in the models. An alternative to the traditional approaches is the artificial neural network inspired by the remarkable abilities of the animals in different tasks. This paper describes the theory and implementation of neural networks for hand-eye calibration and inverse kinematics of a six degrees of freedom robot arm equipped with a stereo vision system. The feedforward neural network and the network training with error propagation algorithm are applied. The proposed approaches are validated in experiments. The results indicate that the hand-eye calibration with simple neural network outperforms the conventional method. Meanwhile, the neural network exhibits a promising performance in solving inverse kinematics. [ABSTRACT FROM AUTHOR]

This paper aims at designing an calibration technique for temperature measurement using support vector machine. The objectives of the present work are: (i) to extend the linearity range of measurement to 100 % of input range, and (ii) to make measurement technique adaptive to variations in physical parameters of thermistor like reference resistance and temperature coefficient. Support vector machine (SVM) is trained to achieve the proposed objectives. The proposed measurement technique is tested considering variations in physical parameters of thermistor like reference resistance ]> and temperature coefficient. Results show that the proposed intelligent technique has fulfilled the set objectives. [ABSTRACT FROM AUTHOR]

Model correlation and model calibration using test data are natural ingredients in the process of validating computational models. Here, model calibration for the important sub-class of non-linear systems consisting of structures dominated by linear behavior having presence of local non-linear effects is studied. The focus is on the selection of uncertain model parameters together with the forming of the objective function to be used for calibration. To give precise estimation of parameters in the presence of measurement noise, the objective function data have to be informative with respect to the parameters chosen. Also, to get useful data the excitation force is here designed to be multi-harmonic since steady-state responses at the side frequencies are shown to contain valuable information for the calibration process. In this paper, test data from a replica of the Ecole Centrale de Lyon (ECL) nonlinear benchmark together with steady-state solutions stemming from calculations using the Multi-Harmonic Balancing method are used for illustration of the proposed model calibration procedure. [ABSTRACT FROM AUTHOR]

Chapter 7 of the book "Advanced Techniques for Assessment Surface Topography" is presented. The issues associated with calibration and traceable measurement using scanning probe microscopes are discussed. A range of calibration procedures for atomic scanning units optimized for three-dimensional (3D) measurement and characterization of surface roughness is also described. A brief overview of error sources in atomic force microscopes (AFM) equipment is given as well.

Chapter 6 of the book "Advanced Techniques for Assessment Surface Topography" is presented. A practical methodology for the calibration of three-dimensional (3D) scanning contact stylus instruments is presented. The development of procedures for the calibration of 3D surface metrology instruments is also outlined. The instrument described are broken down into their sub-elements and their implications on the calibration process are discussed.

In recent years, initial proposals have been presented for advanced driver assistance systems (ADAS) which globally optimize traffic flow by means of the interaction of autonomous vehicles. This kind of ADAS will hereinafter be referred to as traffic assistance system (TAS). For the design, optimization and evaluation of these TAS, investigative simulations simultaneously considering both microscopic and macroscopic behavior are necessary. Therefore, in this paper a two-level approach for calibration and validation of traffic simulations is presented. This contribution presents a new measurement concept that is needed to gather the required data for the suggested two-level approach for calibration and validation. This concept advocates simultaneous data acquisition sourced from both a vehicle (microscopic) and an overall traffic (macroscopic) perspective which is furtheron compared to simulative data of both systemic levels. The paper describes the concept of calibration and validation of a car-following model with respect to intra- und inter-driver-variability, which makes it necessary to consider a distribution for each parameter in use. First empirical parameter distributions and their subsequent use in the Gipp΄s car following model are described in this paper. Results of a macroscopic validation with regard to headway distribution are presented. Compared to the current state of the art, the application of the two-level approach for calibration and validation with the gathered microscopic and macroscopic measurement data will enhance the possibilities to investigate the efficiency of TAS and yield results which are characterized by a higher degree of confidence. [ABSTRACT FROM AUTHOR]

This paper describes a body of work developed over the past five years. The work addresses the use of Bayesian network (BN) models for representing and predicting social/organizational behaviors. The topics covered include model construction, validation, and use. These topics show the bulk of the lifetime of such model, beginning with construction, moving to validation and other aspects of model ˵critiquing″, and finally demonstrating how the modeling approach might be used to inform policy analysis. The primary benefits of using a well-developed computational, mathematical, and statistical modeling structure, such as BN, are 1) there are significant computational, theoretical and capability bases on which to build 2) the ability to empirically critique the model, and potentially evaluate competing models for a social/behavioral phenomenon. [ABSTRACT FROM AUTHOR]

A common approach for solving multi-label classification problems using problem-transformation methods and dichotomizing classifiers is the pair-wise decomposition strategy. One of the problems with this approach is the need for querying a quadratic number of binary classifiers for making a prediction that can be quite time consuming especially in classification problems with large number of labels. To tackle this problem we propose a two stage voting architecture (TSVA) for efficient pair-wise multiclass voting to the multi-label setting, which is closely related to the calibrated label ranking method. Four different real-world datasets (enron, yeast, scene and emotions) were used to evaluate the performance of the TSVA. The performance of this architecture was compared with the calibrated label ranking method with majority voting strategy and the quick weighted voting algorithm (QWeighted) for pair-wise multi-label classification. The results from the experiments suggest that the TSVA significantly outperforms the concurrent algorithms in term of testing speed while keeping comparable or offering better prediction performance. [ABSTRACT FROM AUTHOR]

Spaceborne spectral measurements over long time periods require calibration and monitoring of the instrument as a crucial prerequisite for successful retrieval of atmospheric parameters. Calibration applies a sequence of steps to the measurement data while monitoring assesses the optical performance thus permitting degradation corrections. The parameters characterising the instrument were obtained in a sequence of on-ground calibration runs under different environmental conditions. They are stored as Key Data and serve as input when deriving calibrated spectra. Relevant calibration steps include the memory effect and non-linearity, wavelength calibration and both spectral and spatial stray light corrections. Since SCIAMACHY is sensitive to the polarisation state of the incoming light, polarisation needs to be thoroughly taken into account. The final step performs the radiometric calibration. Once in orbit, the optical performance monitoring establishes information concerning the channel and wavelength dependent degradation. From the combination of the results for the different light paths it is even possible to learn how individual optical components degrade. [ABSTRACT FROM AUTHOR]

The article offers information regarding use of calibration and use of equipment in oedometer consolidation test for the determination of the consolidation characteristics of soils of low permeability. It mentions that the number of loading increments and decrements is dependent on the geotechnical properties to be derived over the particular loading or unloading circumstances under consideration.

The article offers information on calibration of measuring instruments which are required for performing the tests used for determination of the physical properties of soils like shear strength, permeability, and compressibility. It mentions information on calibration of equipment like displacement transducers, pressure gauges, and pressure transducers. It also presents information on calibration of test apparatus like oedometer load frams, and shearbox.

The article focuses on possibility of designing single camera system based on idea of inverse space resection which observes probing device. Topics disucssed include robot calibration used to check robot arm position with nominal position, CAROS+ system which is photogrammetric on-line system and two-camera version for robot calibration.

To reduce the effect from instrument error when getting characteristic parameters of branches of fruit trees by the electromagnetic tracking instrument, a calibration method was sounded based on a discussion of the instrument error of electromagnetic tracking instrument. Finally, the method was tested in an experiment. By comparing the data of the experiment and the standard data which was got by slide caliper, we proved that the method is effective in increasing the accuracy of measurement. [ABSTRACT FROM AUTHOR]

Every year people die at mass events when the crowd gets out of control. Urbanization and the increasing popularity of mass events, from soccer games to religious celebrations, enforce this trend. Thus, there is a strong need to gain better control over crowd behavior. Simulation of pedestrian streams can help to achieve this goal. In order to be useful, crowd simulations must correctly reproduce real crowd behavior. This usually depends on the actual situation and a number of socio-cultural parameters. In other words, what ever model we come up with, it must be calibrated. Fundamental diagrams capture a large number of the socio-cultural characteristics in a very simple concept. In this paper we represent a method to calibrate a pedestrian stream simulation tool so that it can reproduce arbitrary fundamental diagram with high accuracy. That is, it correctly reproduces a given dependency of pedestrian speed on the crowd density. We demonstrate the functionality of the method with a cellular automaton model. [ABSTRACT FROM AUTHOR]

A precise null hypothesis formulation (instead of the more realistic interval one) is usually adopted by statistical packages although it generally leads to excessive (and often misleading) rates of rejection whenever the sample size is large. In a previous paper (Migliorati and Ongaro, 2007) we proposed a calibration procedure aimed at adjusting test levels and p-values when testing the mean of a Normal model with known variance. We now address the more complicated calibration issues arising when a nuisance parameter (e.g., the variance) is present. As procedures for testing the interval null hypothesis available in the literature are shown to be unsatisfactory for calibration purposes, this entails, in particular, the construction of suitable new tests. [ABSTRACT FROM AUTHOR]

A 11-bit 45MS/s pipelined ADC with rapid background calibration of both DAC and gain errors is described. A dual ADC technique is used to achieve calibration within only 104 clock cycles - several orders of magnitude faster than prior state of the art. Measured results from a prototype in a 1.8V, 0.18μm CMOS process show calibration to improve the peak INL of the ADC from 6.4 LSB to 1.1 LSB. [ABSTRACT FROM AUTHOR]

An overview of several state of the art design techniques in achieving good linearity and low power in pipelined ADCs are outlined. Digital calibration is shown as a technique to improve non-idealities which arise due to low DC gain in opamps, and capacitor mismatch in pipelined ADCs. Techniques to reduce ADC power discussed include the elimination of the front-end S/H, open-loop amplifier approaches, and comparator based switched capacitor circuits. [ABSTRACT FROM AUTHOR]

In the last years the Geomatic Research Group of the Politecnico di Torino faced some new research topics about new instruments for point cloud generation (e.g. Time of Flight cameras) and strong integration between multi-image matching techniques and 3D Point Cloud information in order to solve the ambiguities of the already known matching algorithms. ToF cameras can be a good low cost alternative to LiDAR instruments for the generation of precise and accurate point clouds: up to now the application range is still limited but in a near future they will be able to satisfy the most part of the Cultural Heritage metric survey requirements. On the other hand multi-image matching techniques with a correct and deep integration of the point cloud information can give the correct solution for an ˵intelligent″ survey of the geometric object break-lines, which are the correct starting point for a complete survey. These two research topics are strictly connected to a modern Cultural Heritage 3D survey approach. In this paper after a short analysis of the achieved results, an alternative possible scenario for the development of the metric survey approach inside the wider topic of Cultural Heritage Documentation is reported. [ABSTRACT FROM AUTHOR]

Circular dynamic stereoscopy (CDS) has special advantages as it enables a 3-D measurement using a single CCD camera without a cumbersome setting. Spiral streaks are recorded using this system and the size of spiral streaks directly concerns to the depth from the CCD camera. That is, the size of streaks is inversely proportional to the depth from the CCD camera and the three-dimensional information can be measured automatically by image processing technique. In this paper, robot vision system using circular dynamic stereoscopy is introduced. The arm robot is controlled using the measured data of CDS. Experimental results demonstrate the feasibility of our method. [ABSTRACT FROM AUTHOR]

A sensor in a camera takes a gray level image (1536 x 512 pixels), which is reflected by a reference body. The reference body is illuminated by a linear laser line. This gray level image can be used for a 3D calibration. The following paper describes how a calibration program calculates the calibration factors. The calibration factors serve to determine the size of an unknown reference body. [ABSTRACT FROM AUTHOR]

This paper describes the design of a six-axis force/torque sensor, the purpose of which is to provide decoupled and accurate F/T information for the closed-loop control of the manipulator system. Firstly, the manipulator system and the adopted measuring principle are introduced. Then, a novel static component based on dual annulus diaphragms is presented. At last, the calibration and decoupling test based on Neural Network (NN) is carried out. The results of calibration test show superiority of the structure of the elastic component of the developed sensor and the improvement of the calibration method. [ABSTRACT FROM AUTHOR]

Quantifying cumulative environmental impacts (cumulative effects) is challenging due to complex dynamics of natural and human systems interacting. Cumulative effects in social-ecological systems are examples of emergent properties of complex systems, which arise from interactions between multiple resource users. The article presents a multi-agent-based simulation model designed to quantify cumulative effects in the case of interactions between forestry and hunting. The specific contributions of the paper are a) quantification of emergent properties in natural resource management systems, b) evaluation of different road decommissioning policies and the effect on game population sustainability, c) calibration of agent behaviours from numerous empirical studies. Preference weightings in the utility function of hunter agents are calibrated from stated and revealed preference studies of Canadian hunters. Simulations explore moose population sustainability under various forestry access management policies and with different hunter preference parameter configurations. Contrary to the intent of access management, earlier road decommissioning is found to negatively impact overall sustainability of game populations due to cumulative effects of aggregate hunter behaviour. Altering agents΄ preferences for travel cost, game populations, and hunter congestion result in dramatically different spatial outcomes for where game extirpations occur. Certain preference parameter settings create resonance between hunting pressure and game population growth, forming self-organized and persistent spatial resource use patterns. [ABSTRACT FROM AUTHOR]

While human behavior has long been studied, recent and ongoing advances in computational modeling present opportunities for recasting research outcomes in human behavior. In this paper we describe how Bayesian networks can represent outcomes of human behavior research. We demonstrate a Bayesian network that represents political radicalization research – and show a corresponding visual representation of aspects of this research outcome. Since Bayesian networks can be quantitatively compared with external observations, the representation can also be used for empirical assessments of the research which the network summarizes. For a political radicalization model based on published research, we show this empirical comparison with data taken from the Minorities at Risk Organizational Behaviors database. [ABSTRACT FROM AUTHOR]

A body of psychological research has examined the correspondence between a judge΄s subjective probability of an event΄s outcome and the event΄s actual outcome. The research generally shows that subjective probabilities are noisy and do not match the ˵true″ probabilities. However, subjective probabilities are still useful for forecasting purposes if they bear some relationship to true probabilities. The purpose of the current research is to exploit relationships between subjective probabilities and outcomes to create improved, model-based probabilities for forecasting. Once the model has been trained in situations where the outcome is known, it can then be used in forecasting situations where the outcome is unknown. These concepts are demonstrated using experimental psychology data, and potential applications are discussed. [ABSTRACT FROM AUTHOR]

Work has been undertaken at the academy of graduate studies aimed to improve the rainfall rate measurements by radar, so deriving the empirical Z-R relationship for Tripoli City is needed, and also finding a correction factor between Radar and Raingauges readings was of our concern. For the purpose C- band weather radar was used for rainfall rate measurements and calibrated with the four meteorological weather stations located within 50 Km radius of the radar position. The objective was achieved, and Comparison of Tripoli Z-R relation with Marshall and Palmer general formula, for resent weather event in Tripoli city, was also given. [ABSTRACT FROM AUTHOR]

The ionization chamber is the standard instrument for dosimetry in diagnostic radiology. Alternative detectors are those based on semiconductor technology. These dosimeters don΄t require corrections for pressure, are rigid and smaller than ionization chambers, and provide real time information. The main disadvantage of these devices has been their energy dependence which differs considerably from that of ionization chambers. In Technical Report Series n° 457 the International Atomic Energy Agency (IAEA) proposed the `substitution method΄ for calibration of dosimeters at secondary standard dosimetry laboratories (SSDL) based on a comparison between the measured air kerma with a reference ion chamber and a user dosimeter to be calibrated. The present study describes the results concerning the implementation of this method for semiconductor detectors calibration in a laboratory other than a SSDL. The overall uncertainty was better than 7.5% (coverage factor k = 2), being the uncertainty of the reference chamber better than 5%. [ABSTRACT FROM AUTHOR]

Complex interventional radiology (IR) procedures deliver high radiation doses to patients. This may result in skin injury inducted by exceeding deterministic effects threshold. Monitoring and mapping the radiation entrance to the patients is very important to secure patients from medical follow up in case of radiation injury. Basing only on the dose area product (DAP) meters, commonly used in haemodynamic centers, it is impossible to obtain sufficient information about entrance skin dose (ESD) and dose distribution on a patient skin. From this point of view, application of other types of detectors e.g. radiochromic films is suggested. A Gafchromic XR-RV2 film was tested to determine its potential usage for patient skin dose and dose distribution monitoring in a fluoroscopically guided interventional radiology procedures. Films΄ dosimetric characteristic i.e. dose, dose rate, energy and time dependencies in the applied range, were tested. The dose response in different color components of standard RGB color space image and film positioning during scanning were also determined. This work shows that radiochromic films are a simple and pretty useful method that leads to localize and estimating patients΄ skin dose received during interventional radiology procedures. These films can be an alternative for the wellknown dosimetric methods. [ABSTRACT FROM AUTHOR]