37 results about "Scalar potential" patented technology

A unilateral NMR sensor comprising a ferromagnetic yoke; a permanent magnet arranged on the yoke; a pole piece on the magnet; the pole piece including an air-pole piece interface surface whose shape corresponds to an equipotential contour of magnetic scalar potential.

Methods and systems for determining a charge trap density between a semiconductor material and a dielectric material are disclosed. In one respect, spectroscopic data of the semiconductor material may be determined and used to determine a change in dielectric function. A line shape fit of the change in the dielectric function may be applied using derivative function form. The amplitude of the line shape fit may be determined and used to determine an electric field of a space charge region of the semiconductor material. By applying Poisson's equations, the scalar potential due to the electric field in the space charge region may be determined. Subsequently, using the scalar potential the charge trap density may be determined.

An improved method is disclosed for collecting or assembling scalar potential data measurements that are to be subsequently prepared as a surface representation for analysis via frequency domain transform filters. Measurements are made over a geographic reference region which extends in all cardinal directions from the center of some previously determined primary region. The reference dimensions must contain the primary region and must be plural multiples of the greatest depth to be considered in analyzing the contributions to the measurements. A combined or separate improved method for delineating or defining geospatial information contributing to a scalar potential surface is disclosed. This method is implemented using traditional statistical techniques to construct an histogram from the set of values comprising a surface representation. This histogram constitutes a Spatially Correlated Potential Spectrum for the surface. These combined and separate methods improve resolution of geological structures over depths and spatial extents under consideration.

A unilateral NMR sensor comprising a ferromagnetic yoke; a permanent magnet arranged on the yoke; a pole piece on the magnet; the pole piece including an air-pole piece interface surface whose shape corresponds to an equipotential contour of magnetic scalar potential. An approach for designing single-sided magnets suitable for unilateral magnetic resonance (UMR) measurements is presented. The method uses metal pole pieces to shape the field from permanent magnets in a target region. The pole pieces are shaped according to solutions to Laplace's equation, and can be designed using a combination of analytical methods and numerical optimization. The design leads to analytical expressions for the pole piece shape and magnetic field. The method is developed in Cartesian, polar, and spherical coordinates, and the merits of each system are discussed. The effects of finite magnet size on the field quality are explored through simulation, and are found to have a substantial effect in many cases. A magnet is designed using our method to produce a static field with a constant gradient over a region 2 cm in diameter and 2 mm thick. This leads to a compact cylindrical magnet just over 11 cm in diameter, topped with a single metal pole piece. The design is validated through simulation. The simulated field is found to agree closely with that specified analytically through the design procedure.

The invention relates to an electric conductivity rebuilding method for magnetocaloric acoustical imaging. The electric conductivity rebuilding method is based on a magnetocaloric acoustical imaging principle. An exciting coil is used for exerting MHz current excitation on a conducting object, joule heat is generated in the conducting object, and further, ultrasonic signals are generated. An ultrasonic transducer is used for receiving the ultrasonic signals, the received ultrasonic signals are processed and collected, and then, an electric conductivity image of the conducting object is obtained by adopting an electric conductivity image rebuilding algorithm. The electric conductivity rebuilding method comprises the concrete steps that 1, firstly, high-signal-to-noise-ratio magnetocaloric acoustical signals are obtained; 2, the obtained magnetocaloric acoustical signals are used for rebuilding to obtain thermal sound source distribution of the conducting object; 3, the thermal sound source distribution and a one-order magnetic vector space component are used, and a non-linear finite element solution method is adopted for rebuilding a scalar potential space component; 4, the rebuilt scalar potential space component is used for rebuilding the electric conductivity.

A drect iteration-based injection current type thermoacoustic conductivity image reconstruction method is disclosed and comprises the following steps: in a first step, injection current type thermoacoustic signals of an object body are obtained; in a second step, a time reversal method is used for obtaining a thermoacoustic source of the object body according to the thermoacoustic signals; in a third step, an initial value of conductivity is given, and an electric scalar potential is solved; in a fourth step, new conductivity is solved; in a fifth step, the conductivity is solved via iteration. The method comprises the following specific processes: the time reversal method is used for obtaining thermoacoustic source distribution on a certain fault plane, an interpolation method is used for obtaining an overall thermoacoustic source of the object body, the initial value [sigma]0 is given, the electric scalar potential [phi]1 is solved via the known [sigma]0 based on a current continuity theorem, the electric scalar potential [phi]1 is substituted into a relational expression for the thermoacoustic source and the conductivity, updated conductivity [sigma]1 is obtained, [sigma]0 is replaced with [sigma]1, and the above processes are repeated till relative error of the conductivity satisfies epsilon=||([sigma]i-[sigma]i-1) / [sigma]i-1||2<=epsilon0.

The invention discloses a transformer vortex field finite element solving method based on a sinc function. According to the method, first, a model is established for a transformer, and then meshing isperformed on the established model according to a finite element method; the finite element method is adopted to calculate a stiffness matrix and a damping matrix of the model according to unit nodeinformation obtained through meshing; and a magnetic vector potential and a scalar potential are selected to serve as an unknown function of a vortex field mathematical model, a discretization formatis exported through a Galerkin finite element method, a discretization equation set is established, solutions of the discretization equation set are solved through a sinc interpolation method, electric field distribution and magnetic field distribution in a transformer solving domain can be obtained according to the solutions of the equation set, and therefore vortex distribution and loss of the transformer can be calculated. The method is simple in design, easy to implement and easy to popularize, provides more precise analysis for vortex field and loss calculation of large and ultra-large power transformers, provides a basis for transformer design and manufacturing and improves the security and stability of transformer operation.