1765 results about "Initial phase" patented technology

An in vivo examining device and method are described. The in vivo examining device has two operational phases; an initial phase in which the device is of initial dimensions and a final phase in which the device is of final dimensions. In the initial phase the device can pass freely through a normally configured body lumen whereas it may not be able to pass freely through an abnormally configured lumen. In the final phase the device can pass freely through a body lumen even if it is abnormally configured.

The present invention provides improved devices and methods for inhibiting restenosis and hyperplasia after intravascular intervention. In particular, the present invention provides luminal prostheses which allow for programmed and controlled substance delivery with increased efficacy to selected locations within a patient's vasculature to inhibit restenosis. The luminal delivery prosthesis comprises a scaffold which is implantable within a body lumen and means on the scaffold for releasing a substance from the scaffold. The substance is released over a predetermined time pattern comprising an initial phase wherein the substance delivery rate is below a threshold level and a subsequent phase wherein the substance delivery rate is above a threshold level.

The invention discloses a reinforcing learning initial method of a mobile robot based on an artificial potential field and relates to a path planning Q-learning initial method of the mobile robot. The working environment of the robot is virtualized to an artificial potential field. The potential values of all the states are confirmed by utilizing priori knowledge, so that the potential value of an obstacle area is zero, and a target point has the biggest potential value of the whole field; and at the moment, the potential value of each state of the artificial potential field stands for the biggest cumulative return obtained by following the best strategy of the corresponding state. Then a Q initial value is defined to the sum of the instant return of the current state and the maximum equivalent cumulative return of the following state. Known environmental information is mapped to a Q function initial value by the artificial potential field so as to integrate the priori knowledge into a learning system of the robot, so that the learning ability of the robot is improved in the reinforcing learning initial stage. Compared with the traditional Q-learning algorithm, the reinforcing learning initial method can efficiently improve the learning efficiency in the initial stage and speed up the algorithm convergence speed, and the algorithm convergence process is more stable.

Methods and systems for automatically recovering a failed video inspection tool in a precision machine vision inspection system are described. A set of recovery instructions may be associated or merged with a video tool to allow the tool to automatically recover and proceed to provide an inspection result after an initial failure. The recovery instructions include operations that evaluate and modify feature inspection parameters that govern acquiring an image of a workpiece feature and inspecting the feature. The set of instructions may include an initial phase of recovery that adjusts image acquisition parameters. If adjusting image acquisition parameters does not result in proper tool operation, additional feature inspection parameters, such as the tool position, may be adjusted. The order in which the multiple feature inspection parameters and their related characteristics are considered may be predefined so as to most efficiently complete the automatic tool recovery process.

The present invention relates to control of a computer system, which includes a data processing unit, a display and an eye tracker adapted to register a user's gaze point with respect to the display. The data processing unit is adapted to present graphical information on the display, which includes feedback data reflecting the user's commands entered into the unit. The data processing unit is adapted to present the feedback data such that during an initial phase, the feedback data is generated based on an absolute position of the gaze point. An imaging device of the system is also adapted to register image data representing movements of a body part of the user, and to forward a representation of the image data to the data processing unit. Hence, during a phase subsequent to the initial phase, the data is instead generated based on the image data.

A system and method for performing a curve fit on a plurality of data points. In an initial phase, a subset P_max of the plurality of points which represents an optimal curve is determined. This phase is based on a statistical model which dictates that after trying at most N_min random curves, each connecting a randomly selected two or more points from the input set, one of the curves will pass within a specified radius of the subset P_max of the input points. The subset P_max may then be used in the second phase of the method, where a refined curve fit is made by iteratively culling outliers from the subset P_max with respect to a succession of optimal curves fit to the modified subset P_max at each iteration. The refined curve fit generates a refined curve, which may be output along with a final culled subset K_final of P_max.

A method for start-up of a network, including a number of nodes, which are connected via channels. The nodes exchange information in the form of messages via the channels. The transition phase of a synchronizing node from its initial phase to a synchronized phase is separated in a first integration phase and a second subsequent cold-start phase. A synchronizing node in the integration phase listens to messages being sent from nodes in the synchronized phase and only reacts to an integration message (i-frame) if the integration message is a valid message. Furthermore, a synchronizing node, wherein integration of the synchronizing node to a set of already synchronized nodes was not successful after a specifiable period, changes into the cold-start phase, in which a cold-start procedure of the node is extracted, wherein in the cold-start phase the node does not react to integration messages of a node in the synchronized phase.

An optical media disk is treated with a light-sensitive material that impedes the ability of a optical media player from reading data stored on the disk. This light-sensitive material is a material changes phase upon exposure to one or more wavelengths of light. During the initial phase, the light-sensitive material will render the disk unreadable. After activation, however, the disk becomes readable by conventional optical media players. In this fashion, theft of yet-to-be-activated optical media is deterred.

The invention provides a method for tracing the position and pose of a 3D human face in a video sequence. In the method, based on the principal component analysis, by using a deformable 3D grid model, minimizing the distance between a key point on the grid model and a corresponding key point on an input image, the model can fit the head figure of a user; the human face texture can be obtained by using the 3D model at an initial phase, so as to render human face images under different poses; the feature points can be selected in the rendered images, and a corresponding position can be searched on the input image; the matching faults can be removed by using a random sampling mode; then, mode pose changed parameters can be estimated according to the corresponding relationship between the feature points, so as to update a hypothetical state; finally, a distance between the rendered image and an actual image can be calculated by using the average normalized correlation algorithm, so as to calculate a hypothetical weight. Experiments show that the method can effectively trace the pose of the 3D head in the video.

An impact-absorbing protective structure comprises one or more compressible cells. Each cell is in the form of a thin-walled plastic enclosure defining an inner, fluid-filled chamber with at least one small orifice through which fluid resistively flows. Each cell includes an initially resistive mechanism that resists collapse during an initial phase of an impact and that then yields to allow the remainder of the impact to be managed by the venting of fluid through the orifice. The initially resistive mechanism may be implemented by providing the cell with semi-vertical side walls of an appropriate thickness or by combining a resiliently collapsible ring with the cell. After the initially resistive mechanism yields to the impact, the remainder of the impact is managed by the fluid venting through the orifice. The cell properties can be readily engineered to optimize the impact-absorbing response of the cell to a wide range of impact energies.

The invention discloses a method and a system for orthogonal modulation of power signals. The method comprises the following steps: acquiring an initial sequence length and an initial sequence according to a frequency lower limit, a preset sampling frequency and an initially set integer signal cycle number of a power signal; acquiring a reference frequency according to the initial sequence, and further acquiring a unit cycle sequence length and a preset sequence length; acquiring first forward and reverse sequences according to a preset sequence starting point and the preset sequence length; generating first real-frequency and imaginary-frequency vector sequences and second real-frequency and imaginary-frequency vector sequences according to the first forward and reverse sequences; converting obtained first and second phases into a first forward sequence average initial phase; obtaining a new preset sequence starting point according to the average initial phase; and obtaining a cosine function modulation sequence and a sine function modulation sequence according to second forward and reverse sequences obtained from the initial sequence. By adopting the method and the system of the invention, an orthogonal modulation sequence with consistent amplitude height can be obtained, and the accuracy and anti-jamming performance of sinusoidal parameter calculation are improved.

The invention relates to a three-dimensional elliptical vibration cutting device, belonging to the field of cutting and ultra-precision cutting machining of materials which are difficult to machine. A diamond cutter is guided through flexible hinge mechanisms respectively along an X direction, a Y direction and a Z direction, and further, is driven by three piezoelectric stacks respectively alongthe X direction, the Y direction and the Z direction; the piezoelectric stacks of the X direction and the Z direction are preloaded by preloading screw bolts along respective axial direction; the piezoelectric stack of the Y direction is preloaded through a screw bolt screwing wedge; the preloading processes of the three directions are mutually independent; through regulating and matching the initial phase position and the amplitude of a driving signal for each of the three piezoelectric stacks, the projections of the cutter location point movements of the diamond cutter in an X-Y plane and aY-Z plane are elliptical motions, and the projection of the cutter location point movements of the diamond cutter in an X-Z plane is reciprocating elliptical motion or linear motion. The three-dimensional elliptical vibration cutting device has a novel and simple structure, is easy to implement, and is beneficial to obtaining the best cutting machinability of the diamond cutter.

The invention provides a vector averaging calibration method for a phased-array antenna, and aims to provide a vector averaging calibration method capable of improving calibration accuracy and avoiding the influence of phase-shifting errors of branch phase shifters. The method comprises the following steps of: (1) serially/parallelly connecting the phase-array antenna with N units and N transmitter-receiver (TR) components comprising N phase shifters to obtain a calibration feed network, and connecting each phase-array antenna feed branch to a calibration amplitude phase receiver through a beam-forming network and the calibration feed network to obtain a transmitter-receiver circuit; (2) setting a phase-array antenna feed branch consisting of the beam-forming network and the TR components comprising the phase shifters as an object to be calibrated, and performing phase shift on the phase shifters by using a wave shaper; and (3) obtaining the initial phase and amplitude distribution of each branch by using a vector averaging algorithm, wherein the difference between the phase and the amplitude distribution and the designed phase and amplitude distribution is a calibration parameter. The calibration method has the advantages of high accuracy and engineering applicability.

A method for operation of a node operating in a wireless network comprising the steps of during an initial phase, setting transmission power and data transmission rate to initial settings and transmitting the initial settings to the wireless network in order to initiate communication with said wireless network during a reference phase once communication with the wireless network is established by the initial phase, transmitting at maximum power while performing a rate adaptation and at least one variable estimation and during an operational phase, transmitting at a power level that is optimal for transmission based on information obtained from the reference phase.

The invention relates to a three-dimensional elliptic motion generating method and a three-dimensional elliptic motion generating device for a diamond cutter, which belong to the field of ultraprecise cutting and cutting of materials difficult to machine. The diamond cutter is directly driven by three piezoelectric stacks which are arranged vertically, the three piezoelectric stacks are pre-tightened by a pre-tightening bolt at the same time, and the pre-tightening forces of the three piezoelectric stacks are finely adjusted by three wedge mechanisms respectively; by actively controlling the initial phase of a three piezoelectric stack driving signal, the projections of the motion of the diamond cutter on an X-Y plane and a Y-Z plane are elliptic motions, and the projection of the motion of the diamond cutter on an X-Z plane is a reciprocating linear motion; and by regulating the parameters such as frequency and amplitude of the three piezoelectric stack driving signal, the automatic control over the three-dimensional elliptic motion track parameter of the cutter is realized. The method and the device are very simple, easy to implement and favorable for obtaining the optimal cutting machinability of the diamond cutter.

One fixed narrow beam and one sector beam are generated by an antenna array. Multiple fixed narrow beams are realized by shaping technique of simulating fixed beams and using shaping network (Butler array) of fixed narrow beams. A sector beam covering whole sector is formed through controlling initial phase of beam at Butler array side by using phasing adjustment device. Signal energy of sector beams at side of each component of antenna array is equal or approximately equal. Thus, amplitude of transmitted signal of each component of antenna array is lowered.

The invention relates to an on-line monitoring method of low-frequency oscillation of a power system. In the on-line monitoring method, parallel filtration calculation is carried out at an oscillation frequency by creatively utilizing time-frequency atom compound band-pass filter function to obtain oscillation mode number, practical oscillation frequency distribution and real-time amplitude information. On the basis of the redundancy of adjacent real-time amplitude information, various oscillation mode amplitudes and decay time constants can be obtained by utilizing least square optimization estimation; based on the obtained oscillation frequency distribution, amplitude and decay time constant, a low-frequency oscillation signal model can be built, wherein only an initial phase and direct-current component amplitude of each mode are unknown; and optimization estimation is carried out on the model by utilizing a particle swarm optimization algorithm to obtain the initial phase and the direct-current component amplitude. The method has good noise robustness, can be used for accurately distinguishing compound oscillation models, is favorable for the strong non-linear mode analysis ofthe power system and is convenient for on-line monitoring and application.

The invention discloses a non-linear structure light illumination microscopic imaging method which comprises the following steps: 1) loading a computed hologram on a digital microscopic array; 2) generating a first spatial structure light field which meets sine distribution and is used for activating fluorescent protein, and radiating the first spatial structure light field to the surface of a sample, so as to convert a part of protein to be in an illuminated state from a dark state; 3) radiating the sample in a second spatial structure light field so as to enable fluorescent protein in the bright state to emit fluorescent light, collecting the fluorescent light, and imaging in a photoelectric detector; 4) repeating the step 2) and the step 3), acquiring a plurality of spatial frequencies, acquiring a plurality of initial phases in each direction to obtain a plurality of original images, and reestablishing a super-resolution image according to a GPU acceleration algorithm. The invention further discloses a non-linear structure light illumination microscopic imaging system. The non-linear structure light illumination microscopic imaging method has the advantages of relatively high system imaging resolution, high fluorescent drifting resistance, low phototoxicity and rapid imaging.

The invention discloses a harmonic analysis method based on Kaiser self-convolution window dual-spectrum line interpolation FFT (Fast Fourier Transform) and a device thereof. The method comprises the following steps of sampling a signal: sampling a time-domain continuous signal, and discretizing to obtain an infinitely long discrete sequence; windowing a four-order Kaiser self-convolution window function: performing four-order Kaiser self-convolution window operation on the infinitely long discrete sequence; performing N-point FFT on a windowed and truncated signal to obtain the discrete spectrum of the signal; determining the peak parameter of the discrete spectrum: searching the local spectrum peak of each integer harmonic frequency around the integer harmonic frequency; and calculating a harmonic parameter: solving a coefficient alpha by adopting a discrete spectrum interpolation correction formula based on an LSM (Least Square Method), and calculating parameters such as a harmonic frequency, an amplitude, an initial phase angle and the like. Due to the adoption of the method, the fundamental and harmonic components of a tested signal can be detected rapidly and accurately, and accurate frequency measurement is realized; and the method is convenient for implementing an embedded system, and the tested signal can be detected continuously for a long time.

A rotation detecting device includes a plurality of magnetic encoders disposed coaxially and having respective numbers of magnetic poles different from each other and a plurality of magnetic sensors for detecting respective magnetic fields emanating from those magnetic encoders. Each of the magnetic sensors is in a ring form and obtains the position information within the magnetic poles of the associated magnetic encoder. A phase difference detector determines the difference in phase between magnetic field signals detected respectively by the magnetic sensors. An angle calculator is provided, which is operable on the basis of the difference in phase so detected to calculate an absolute angle of each of the magnetic encoders. A corrector corrects the initial phase difference occurring in the magnetic field signals, detected respectively by the magnetic sensors, as a result of the fitting position of the magnetic encoders.

The invention provides circuits and methods for estimating and correcting nonlinear error in analog to digital converters that is introduced by nonlinear circuit elements, for example one or more residue amplifiers in a pipelined analog to digital converter integrated circuit. In a preferred method of the invention, pseudo random calibration sequences are introduced into the digital signal to be converted by a flash digital to analog converter in one or more initial stages of the pipelined analog to digital converter circuit. A digital residue signal of the output of the one or more initial pipelined analog to digital converter stages is sampled. Intermodulation products of the pseudo random calibration sequences that are present in the digital residue signal are determined to estimate nonlinear error introduced by the residue amplifier in the one or more stages. A digital correction signal is provided to the output of the one or more stages to cancel estimated nonlinear error.

The invention discloses a phase error compensation method applied to grating three-dimensional projection measurement. The method includes the following steps: generating sine grating stripes; collecting grating stripes that are modulated by the surface of an object; pre-processing images; carrying out phase unwrapping through a phase shift method on the basis of the pre-processed stripe images; projecting a grey-scale image with a single gray value onto the surface of a standard white board; mapping regional results in the step (5) onto a target surface of a projector through an obtained ideal phase; establishing regional correction models for different regions according to the regional results; projecting the sine grating stripes onto the object; solving an initial phase through a phaseshift method, compensating the phase on the basis of established regional error compensation, and solving an actual phase; and through calibrated camera parameters and a solved absolute phase, calculating three-dimensional coordinate information of a to-be-measured object through a spatial intersection method. The method overcomes phase errors and measurement errors caused by Gamma non-linearity.