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The calibration is a key but cumbersome process for 3D body scanning using multiple depth cameras. The purpose of this paper is to simplify the calibration process by introducing a new method to calibrate the extrinsic parameters of multiple depth cameras simultaneously.

An improved method is introduced to enhance the accuracy based on the virtual checkerboards. Laplace coordinates are employed for a point-to-point adjustment to increase the accuracy of scanned data. A system with eight depth cameras is developed for full-body scanning, and the performance of this system is verified by actual results.

The agreement of measurements between scanned human bodies and the real subjects demonstrates the accuracy of the proposed method. The entire calibration process is automatic.

A complete algorithm for a full human body scanning system is introduced in this paper. This is the first publically study on the refinement and the point-by-point adjustment based on the virtual checkerboards toward the scanning accuracy enhancement.

This paper presents preliminary results of the modeling of a large autonomous quad-rotor airship, with flying wing shape. This airship is supposed to be a flexible body. This study promotes an entirely analytical methodology with some assumptions. In this study and as first assumption, the shape of the careen is supposed to be an elliptic cone. To retrieve the velocity potential shapes, this paper solved the Laplace’s equation by using the sphero-conal coordinates. This leads to the Lamé’s equations. The whole system equations governing the interaction of air–structure, including the boundary conditions, is solved in an analytical setting.

This paper opted for a modeling and determination of the added masses of a flexible airship by an analytical method illustrated by a comparison with a geometric method. This analytical method includes the study of complex functions which are the Lamé functions.

This paper provides an analytical way to estimate an aerodynamic phenomenon which acts on the airship and in particular on its envelope and known as the phenomenon of added masses or virtual masses, as well as the means of defining it and the calculation analytically for the case of the flexible airship.

Considering that the calculation of the added masses is very difficult and the numerical methods increase the number of degrees of freedom, the analytical method established in this paper has become a solution of calculations of these virtual masses.

This paper includes an application for determining the added masses of a new generation MC500 airship.

This paper allows defining an analytical method which determines the added masses of an airship, which helps the automation engineer to develop a control strategy to stabilize this airship.

The problems of transient natural convection from a corrugated plate embedded in an enclosed porous medium is studied numerically. The non‐Darcian effects as well as the acceleration terms are taken into consideration in the momentum equation. The governing equations in terms of vorticity, stream function and temperature are expressed in a body‐fitted coordinates system, which were solved numerically by the finite difference method. Results are presented in terms of streamlines and isotherms, local and average Nusselt numbers, with Darcy‐Rayleigh number ranging from 0 to 1000, and Darcy number from 10^–4 to 10^–1, for several aspect ratios of the cavity and plate positions. The flow and heat transfer characteristics for a corrugated plate and a flat plate and the numerical results solved with four different mathematical models are also compared.

The purpose of this paper is to establish the mathematical foundations of magnetic measurement methods based on translating-coil and rotating-coil magnetometers for accelerator magnets and solenoids. These field transducers allow a longitudinal scanning of the field distribution, but require a sophisticated post-processing step to extract the coefficients of the Fourier–Bessel series (known as pseudo-multipoles or generalized gradients) as well as a novel design of the rotating coil magnetometers.

Calculating the transversal field harmonics as a function of the longitudinal position in the magnet, or measuring these harmonics with a very short, rotating induction-coil scanner, allows the extraction of the coefficients of a Fourier–Bessel series, which can then be used in the thin lens approximation of the end regions of accelerator magnets.

The extraction of the leading term in the Fourier–Bessel series requires the solution of a differential equation by means of a Fourier transform. This yields a natural way to de-convolute the measured distribution of the multipole content. The author has shown that the measurement technique requires iso-parametric coils to avoid interception of the longitudinal field component. The compensation of the main signal cannot be done with the classical arrangement of search coils at different radii, because no easy scaling law exists. A new design of an iso-perimetric induction coil has been found.

In the literature, it is stated that the pseudo-multipoles can be extracted from field computations or measurements. While this is true for computations, the author shows that the measurement of the field harmonics must be done with iso-parametric coils because otherwise the leading term in the Fourier–Bessel series cannot be extracted.

The author has now established the theory behind a number of field transducers, such as the moving fluxmeter, the rotational coil scanner and the solenoidal field transducer.

This paper brought together the known theory of the orthogonal expansion method with the methods and tools for magnetic field measurements to establish a field description in accelerator magnets.

The aim of this paper is to study and analyse the advantages and limitations of the scanning reference electrode technique (SRET) to detect and assess localised electrochemical activity based on an evaluation of the influence of the principal test parameters on the sensitivity and resolution of the technique.

Measurements of Ohmic potential gradients induced by ionic flux close to a point current source (PCS) were carried out using a scanning reference electrode technique (SRET) instrument, which comprised a vertical rotating working electrode and a scanning probe formed by a pair of platinum electrodes of approximately 200 μm of diameter. Ionic flux was induced by anodic polarisation applied to a gold micro‐disc electrode, which acted as the PCS. Measurements were conducted in electrolytes of ten different conductivities, using different scanning probe tips to sample surface distance and different working electrode rotation rates. The range of conductivities used included most of the possible electrolytes to which metallic materials can be in contact under real service conditions.

The SRET signal sensed from a polarised PCS showed a strong dependence on the rotation rate of the working electrode for electrolytes of low conductivity but a minimal effect on electrolytes with conductivities higher than 50 mS/cm.

This work presents the effect of wide variations on the electrochemical and operational conditions on the sensitivity and resolution of SRET signal response and discusses the limitations of the technique to assess localised electrochemical activity due to the effect of high conductivity electrolytes, large separation distance between the SRET scanning probe and developing dissolution and scanning rate of a the localised site.

Heat and fluid flow through a trapezoidal cooling chamber were studied numerically. Hot fluid is assumed inflow at some depth below the surface into one end of the chamber and withdrawn at another depth from the other end. The top of the chamber is exposed to the surrounding for cooling and the remaining side‐walls are all insulated. Inflow Reynolds number Ro considered is in the range of 100 to 1000 and the inlet densimetric Froude number Fo considered is in the range of 0.5 to 50.0. Numerical experiments show that the flow and temperature fields in the flow‐through trapezoidal chamber are strong function of both Fo and Ro. The submergence ratio D/do, chamber length to depth ratio L/D and chamber wall angles are also significant in influencing the flow fields. Comparisons were also made with available experimental and prototype data.

The purpose of this paper is to present the development and comparison of selected time‐domain and Laplace‐domain methods for the simulation of waves propagating along multiconductor transmission lines (MTLs), both uniform and nonuniform, and sensitivities with respect to distributed and lumped parameters of MTL systems.

A methodology is based on discrete, semidiscrete and continuous MTL models formulated and solved both in the time and Laplace domains, latter combined with a numerical inverse Laplace transform (NILT).

The most accurate method is that based on the MTL Laplace‐domain continuous model, processed via the MTL chain matrix and connected with an NILT. This method concurrently shows minimal RAM requirements, and in case of uniform MTLs, it runs fastest. For nonuniform MTLs, however, the implicit Wendroff formula is fastest, as long as the RAM is available.

The research is limited to linear MTLs only and the methods suppose terminating circuits based on their generalized Thévenin equivalents. They can be, however, generalized for more complex systems via more sophisticated boundary conditions treatment. The time‐domain methods have further potential to be generalized towards nonlinear MTLs.

The methods considered can contribute to solving signal integrity issues in high‐speed electronic systems, the Matlab routines developed can serve in education process as well.

The implicit Wendroff formula has been adapted to enable simulation of voltage and/or current distributions and their sensitivities along the nonuniform MTLs' wires. Besides, semidiscrete and continuous nonuniform MTL models have been elaborated to enable sensitivities determination, both in the time and Laplace domains, latter connected with the NILT technique based on fast Fourier transform/inverse fast Fourier transform and quotient‐difference algorithms.

Light, when constructed in terms of the elementary quanta of light, may be viewed in particle‐like or wave‐like terms. The elementary quanta of light, when placed in motion through space/time at a speed of a constancy of c forms a light path through the space or reference frame viewed. The light path formed is curved, as space/time is curved. The curvilinear light path formed is a function of the gravitational potential within the viewed frame of reference. The linear description of this light path, termed the geodesic (Riemannian), does not describe the curvilinear light path, but rather the chord of the curvilinear path described by the inscribed arc. This linear description of the light path is the manner in which we describe the coordinate system involved, and is the same manner in which we determine the “speed of light”. The arc length of the light path, compared to the lesser value as described by the chord length, allows for a displacement to be determined, if both measures are applied to a linear measure. A displacement of linear coordinates then occurs, with this displacement a result of the gravitational potential occurring within the frame viewed. This displacement, derived via observation and predictions of the quantum model, resolves Maxwell as well as Newton. The theory concludes that the Special Theory of Relativity, suitably modified to account for gravitational displacement within one particular frame, derives a precise relative model of gravitation within the special frame. This model satisfies Newton, as the model arrives at an exact description of the three‐body problem.

The purpose of this paper is to propose a numerical procedure for discrete identification of the missing part of the domain boundary in a heat conduction problem. A new approach to sensitivity analysis is intended to give a better understanding of the influence of measurement error on boundary reconstruction.

The solution of Laplace’s equation is obtained using the Trefftz method, and then each of the sought boundary points can be derived numerically from a nonlinear equation. The sensitivity analysis comes down to the analytical evaluation of a sensitivity factor.

The proposed method very accurately recovers the unknown boundary, including irregular shapes. Even a very large number of the boundary points can be determined without causing computational problems. The sensitivity factor provides quantitative assessment of the relationship between the temperature measurement errors and boundary identification errors. The numerical examples show that some boundary reconstruction problems are error-sensitive by nature but such problems can be recognized with the use of a sensitive factor.

The present approach based on the Trefftz method separates, in terms of computation, specification of the coefficients appearing in the Trefftz method and missing coordinates of the sought boundary points. Due to introducing a sensitivity factor, a more profound sensitivity analysis was successfully conducted.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.