Abstract: Provided are a magnetic resonance chemical-shift-encoded imaging method, apparatus, and device, belonging to the technical field of magnetic resonance imaging. The method comprises: in a phasor-error plot established on the basis of a two-point magnetic resonance signal model, determining to be an initial seed point a pixel having a unique phasor and causing said plot to reach a minimal local value; according to the initial seed point, estimating the phasor value of a to-be-estimated pixel to obtain a field map; mapping and merging the field map at the highest resolution to obtain a reconstructed field map; determining a reconstructed seed point from the reconstructed field map, and estimating the reconstructed seed point to obtain the phasor value of the reconstructed to-be-estimated pixel; according to the reconstructed seed point and the phasor value of the reconstructed to-be-estimated pixel, obtaining two separate images having predetermined components.

Abstract: Disclosed is a microfluidic system based on an artificially structured acoustic field, comprising a microcavity and a ultrasonic emission device, wherein the microcavity is used to accommodate a solution containing particles, the ultrasonic emission device is used to emit ultrasound, and characterized in further comprising a phononic crystal plate placed in the microcavity, wherein the phononic crystal plate has an artificial cycle structure, and is used to modulate the acoustic field so as to control the particles. Also disclosed is a method of controlling microfluid particles based on an artificially structured acoustic field. In the particular embodiments, since a microcavity, an ultrasonic emission device and a phononic crystal plate are comprised, the ultrasonic emission device is used to emit ultrasound, and the phononic crystal plate has an artificial cycle structure, and is used to modulate the acoustic field so as to control the particles.

Abstract: A secondary battery and its preparation method, the secondary battery having a negative electrode containing a negative current collector; and no negative active material; an electrolyte having an electrolyte salt and an organic solvent a separator; a positive electrode having a positive active material layer containing a positive active material, wherein the positive active material comprises a material having a layered crystal structure; and a battery case used for packaging. Main active component of the secondary battery is the positive active material having a layered crystal structure, which is environmentally-friendly and low in cost; meanwhile, negative active material is not needed by he second battery system, thereby remarkably reducing the weight and cost of the battery and improving the battery energy density. The reaction mechanism adopted by the secondary battery significantly increases the working voltage of the battery and further improves the energy density of the battery.

Abstract: The present disclosure provides a three-dimensional point cloud model reconstruction method and a device.

Abstract: The present disclosure provides a navigation method based on a three-dimensional scene, comprising: calculating an interest value of a viewpoint of a camera based on heights, volumes, irregularities and uniqueness of buildings in a scene; generating trajectory parameters of the camera according to the interest value of the viewpoint, so as to navigate according to the trajectory parameters. The navigation method based on a three-dimensional scene of the present disclosure obtains a reasonable interest value of the viewpoint based on heights, volumes, irregularities and uniqueness of the buildings, thereby achieving a high-quality navigation.

Abstract: A method for reconstructing a three-dimensional model of point clouds includes following steps: a, scanning to obtain point clouds of an object required for a three-dimensional model reconstruction; b, analyzing quality of the obtained point clouds; c, computing a new scanning view based on the analyzed point clouds; d, scanning according to the new scanning view and updating the point clouds of step a based on point clouds obtained by the scanning according to the new scanning view in real time; and e, reconstructing a three-dimensional model according to the point clouds updated in real time. The invention further relates to a system for reconstructing a three-dimensional model of point clouds. The invention can realize full automatic reconstruction of a three-dimensional model and create a model of point clouds with high quality. In addition, the invention is easy to implement and can achieve high efficiency.

Abstract: Disclosed is a magnetic resonance rapid parameter imaging method and system. The method comprises: obtaining a target undersampled magnetic resonance signal (S10); obtaining prior information of a parameter model (S20); performing sequence reconstruction of a target image according to the undersampled magnetic resonance signal and the prior information to obtain a target image sequence (S30); and substituting the target image sequence into the parameter estimation model to obtain object parameters and to generate parametric images (S40).

Abstract: Disclosed is an indoor positioning device which comprises a base, a light source mounted on the base, a rotating part, a rotating outer shell and a controller; the rotating outer shell is a hemispherical shell body or a shell body being tangent externally with a hemispherical surface; a luminous point is located at a spherical center of the rotating outer shell; the rotating outer shell is divided into a plurality of encoded rings, each encoded ring is divided into a plurality of encoding bits, a angle ? of each encoding bit in a latitudinal direction is 360/N degrees, different encoded rings has different arrangements of encoding bits; in each encoded ring, some encoding bits are in a transparent state, there is no arrangement of two continuous opaque encoding bits, some encoding bits arranged in a specified style constitute a start bit or an end bit; once a light barrier of the rotating part passes through an optical coupler, the light source generates a frequency hopping; a receiver senses an optical signa

Abstract: An ultrasound probe calibration system and method. The system comprises an ultrasound probe calibration phantom (100), and the ultrasound probe calibration phantom (100) is provided with a sunken recess (110) at a middle position of an upper surface thereof and with several conical holes on a side surface thereof. The sunken recess (110) is fixedly connected with a two dimensional ultrasound probe (220) therein. The conical hole is inserted with an NDI insertion stylus (230), and a tip of the NDI insertion stylus (230) can be acquired in ultrasound imaging. An ultrasound probe calibration system employing the above structure enables a midplane of an ultrasound plane to pass a midplane of an ultrasound probe calibration phantom (100) along a middle gap, such that a tip of an NDI insertion stylus (230) is used for the midplane of the ultrasound plane, thereby addressing the problem of misalignment of a point-type phantom or a two-dimensional plane-type phantom to the ultrasound plane.

Abstract: Provided is a method for extracting an image salient curve. The method comprises the following steps: drawing an approximate curve along a salient edge of an image from which a salient curve is to be extracted; obtaining short edges in the image; calculating a harmonic vector field by using the drawn curve as a boundary condition; filtering the short edges in the image by using the harmonic vector field; updating the vector field by using the short edges left in the image as boundary conditions; and obtaining an optimal salient curve of the image by using the energy of a minimized spline curve in the vector field. Also provided is a system for extracting an image salient curve. The image salient curve can ensure the smoothness and a bending characteristic.

Abstract: A suturing nail includes a first nail body a second nail body being intertwined mutually to form a helix portion; a first nail crown extending from an end of the first nail body; a second nail crown extending from an end of the second nail body and opposite to the first nail crown, the first and the second nail crown being located on the same side of the helix portion and perpendicular to the helix portion; a first nail leg extending from the other end of the first nail body; a second nail leg extending from the other end of the second nail body and being spaced from the first nail, the first and the second nail leg are located on the same side of the helix portion, the first nail leg and the second nail leg are parallel to the helix portion. The suturing nail is not deformed easily.

Abstract: Disclosed is a method for automatically optimizing point cloud data quality, including the following steps of: acquiring initial point cloud data for a target to be reconstructed, to obtain an initial discrete point cloud; performing preliminary data cleaning on the obtained initial discrete point cloud to obtain a Locally Optimal Projection operator (LOP) sampling model; obtaining a Possion reconstruction point cloud model by using a Possion surface reconstruction method on the obtained initial discrete point cloud; performing iterative closest point algorithm registration on the obtained Possion reconstruction point cloud model and the obtained initial discrete point cloud; and for each point on a currently registered model, calculating a weight of a surrounding point within a certain radius distance region of a position corresponding to the point for the point on the obtained LOP sampling model, and comparing the weight with a threshold, to determine whether a region where the point is located requires rep

Abstract: A magnetic resonance multi-core array radio frequency device and a magnetic resonance signal receiving method are provided. The device comprises a radio frequency receiver which includes a radio frequency coil (11), a low noise preamplifier (13), a multiplexer (15), a radio frequency band-pass filter (17), a program control amplifier (19), a frequency synthesizer (21), a mixer (23), an analog to digital converter (29) and a controller (31). The controller (31) is used for controlling the multiplexer (15) to select a corresponding radio frequency coil channel, a corresponding filtering channel, gain of the radio frequency band-pass filter (17), and receiving a magnetic resonance digital signal transmitted by the analog to digital converter (29). Due to the multiplexer (15), there is no need to configure different circuits respectively for different nuclear magnetic resonance, redundancy of the circuits is reduced, and cost is reduced.

Abstract: Provided are an image restoration method and device. The method comprises: processing image blocks, which are initially registered, to acquire connection curves among the image blocks; constructing an ambient field of images to be restored by means of the connection curve; by minimizing energy of the connection curve in the ambient field, registering the image blocks; and performing image filling on the registered image blocks to acquire a restored image. The device comprises: a processing unit used for processing the image blocks, which are initially registered, to acquire the connection curve among the image blocks; an ambient field construction unit used for constructing the ambient field of the image to be restored by means of the connection curve; a registering unit used for registering the image blocks by minimizing the energy of the connection curve in the ambient field; and a filling unit used for performing image filling on the registered image blocks to acquire the restored image.

Abstract: Disclosed is a magnetic resonance rapid parameter imaging method and system. The method comprises: obtaining a target undersampled magnetic resonance signal (S10); obtaining prior information of a parameter model (S20); performing sequence reconstruction of a target image according to the undersampled magnetic resonance signal and the prior information to obtain a target image sequence (S30); and substituting the target image sequence into the parameter estimation model to obtain object parameters and to generate parametric images (S40).

Abstract: A method for extracting a skeleton form a point cloud includes: obtaining inputted point cloud sampling data; contracting the point cloud using an iterative formula and obtaining skeleton branches, the iterative formula is: argmin X ? ? i ? I ? ? ? j ? J ? ? ? x i - q i ? ? ? ? ( ? x j - q j ? ) + R ? ( X ) , ? wherein R ? ( X ) = ? i ? I ? ? ? i ? ? i ? ? I ? \ ? { i } ? ? ? ? ( ? x i - x i ? ? ) ? i ? ? x i - x i ? ? , ? ? ( r ) = ? - 4 ? ? r 2 h 2 , wherein J represents a point set of the point cloud sampling data, q represents the sampling points in the point set J, I represents a neighborhood point set of the sampling points q, x represents the neighborhood points in the neighborhood point set I, R is a regular term, ? is a weighting coefficient, h is a neighborhood radius of the neighborhood point set I, and ? is a distribution coefficient; and connecti

Abstract: A method for extracting a skeleton form a point cloud includes: obtaining inputted point cloud sampling data; contracting the point cloud using an iterative formula and obtaining skeleton branches, the iterative formula is: arg ? ? min X ? ? i ? I = ? ? j ? J ? ? x i - q i ? ? ? ? ( ? x j - q j ? ) + R ? ( X ) , wherein R ? ( X ) = ? i ? I ? ? i ? ? i ? ? I / { i } ? ? ? ( ? x i - x i ? ? ) ? i ? ? x i - x i ? ? , ? ? ( r ) = ? 4 ? ? r 2 h 2 , wherein J represents a point set of the point cloud sampling data, q represents the sampling points in the point set J, I represents a neighborhood point set of the sampling points q, x represents the neighborhood points in the neighborhood point set I.

Abstract: Provided is a method for extracting an image salient curve. The method comprises the following steps: drawing an approximate curve along a salient edge of an image from which a salient curve is to be extracted; obtaining short edges in the image; calculating a harmonic vector field by using the drawn curve as a boundary condition; filtering the short edges in the image by using the harmonic vector field; updating the vector field by using the short edges left in the image as boundary conditions; and obtaining an optimal salient curve of the image by using the energy of a minimized spline curve in the vector field. Also provided is a system for extracting an image salient curve. The image salient curve can ensure the smoothness and a bending characteristic.

Abstract: The present disclosure relates to a multi-sensor indoor localization method and device. The method includes: an optical signal is received from a point light source using an optical sensor group having N optical sensors; the light intensity of the optical signal is obtained, the optical sensor group includes a polyhedron-shaped base where the normal vectors of each three faces are linearly independent, the N optical sensors are located on the faces of the base, and N?6; the current heading is obtained by a magnetic sensor group; a current unit normal vector is obtained; a system of at least three equations is established; the system of equations is solved to obtain an approximate solution of minimum residual, the approximate solution is regarded as the coordinates of the optical sensor group.

Abstract: Disclosed is a method for automatically optimizing point cloud data quality, including the following steps of: acquiring initial point cloud data for a target to be reconstructed, to obtain an initial discrete point cloud; performing preliminary data cleaning on the obtained initial discrete point cloud to obtain a Locally Optimal Projection operator (LOP) sampling model; obtaining a Possion reconstruction point cloud model by using a Possion surface reconstruction method on the obtained initial discrete point cloud; performing iterative closest point algorithm registration on the obtained Possion reconstruction point cloud model and the obtained initial discrete point cloud; and for each point on a currently registered model, calculating a weight of a surrounding point within a certain radius distance region of a position corresponding to the point for the point on the obtained LOP sampling model, and comparing the weight with a threshold, to determine whether a region where the point is located requires rep