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35 results about "Ratio Sequence" patented technology

The common ratio in a geometric sequence is the constant ratio between any term and the term after it. A common ratio is also called a geometric ratio. For example, the geometric sequence { 1, 3, 9, 27 } has a common ratio of 3.

PFC (power factor correction) control method with high input power factor and control circuit thereof

The invention provides a PFC (power factor correction) control method with high input power factor and a control circuit thereof. The method comprises the steps of controlling a switching tube to be switched on and switched off according to the principle of leading impulse area to be equivalent, and leading input inductive current and sinusoidal half-wave current to have the equivalent impulse area in each switching period, thereby realizing the high power factor (PF); furthermore, the higher the switching frequency, the closer to 1 the PF value is. In the control circuit, a circuit topological structure of a Boost converter and a control circuit for realizing a variable duty ratio sequence jointly constitute a PFC stage of a commonly used LED (light-emitting diode) driving power supply, the front stage of the PFC stage is connected with the output end of a non-controllable rectifier bridge of a single-phase diode via an input filter capacitor, the back stage of the PFC stage is connected with a DC / DC (direct current / direct current) stage of the commonly used LED driving power supply via an output filter inductor and an output filter capacitor. By adopting the PFC control method, not only the very high input power factor can be realized, but also output voltage ripple can be reduced; furthermore, the control circuit is simple and easy to realize an analog circuit, thereby being conductive to large-scale integration.
Owner:SOUTH CHINA UNIV OF TECH

Multistage pulse amplitude modulator with function of achieving amplitude equalization of modulation signal

The invention discloses a multistage pulse amplitude modulator with a function of achieving amplitude equalization of a modulation signal. The multistage pulse amplitude modulator comprises n Mach-Zahnder intensity modulators in series connection, wherein input ports and output ports of the Mach-Zahnder intensity modulators are connected end to end, and the input port of a first Mach-Zahnder intensity modulator is utilized as a light source input port, the output port of a final Mach-Zahnder intensity modulator is utilized as a modulation signal output port, and OOK signals with the same amplitude are loaded to each Mach-Zahnder intensity modulator, thereby achieving the modulation of 2N-stage pulse amplitude modulation signals; the effective modulation arm length ratio among the n Mach-Zahnder intensity modulators is 20 : 21: 22 : ... : 2N-1, and the arrangement sequence of the Mach-Zahnder intensity modulators with the above effective modulation arm length ratio does not limit to the above ratio sequence. According to the multistage pulse amplitude modulator with the function of achieving the amplitude equalization of the modulation signal, by improving the structure of the modulator, the flexible control of a phase bias point and the equalization of optical signals on the two arms of the modulator when the modulation signal is modulated are achieved, and the extinction ratio of the modulator is increased.
Owner:WUHAN POST & TELECOMM RES INST CO LTD

Decoding processing method and decoder

The embodiment of the invention provides a decoding processing method and a decoder. The method includes the steps of receiving a log-likelihood ratio sequence sent by a decoding modulator, conducting pre-decoding on the log-likelihood ratio sequence to obtain at least two posterior probability log-likelihood ratio sequences, and conducting decoding on the posterior probability log-likelihood ratio sequences to obtain decoding results. The decoding processing method and the decoder can improve the performance gain of decoding.
Owner:HUAWEI TECH CO LTD

Method for positioning blockage point in non-metal pipeline by means of ground penetrating radar

The invention discloses a method for positioning a blockage point in a non-metal pipeline by means of ground penetrating radar. The method includes the following steps: 1, obtaining test data of a blocked segment in a non-metal pipeline by means of ground penetrating radar; 2, obtaining a random number of scan points of a random number of scan lines, and selecting natural resonant response wave bands of the scan points right over the pipeline; 3, extracting the pole resonant frequency, and obtaining a resonant frequency difference; 4,obtaining a corresponding water level through interpolation; and 5, obtaining a caliber water level ratio sequence, drawing a relation curve of a scan line position and a caliber water level ration, and obtaining a water level sudden drop point, wherein the position of the scan line corresponding to the point is a blockage point of the non-metal pipeline. The blockage point in a non-metal pipeline can be quickly positioned. Therefore, the detection cost is reduced, the on-line detection difficulty is reduced, and the work efficiency is improved.
Owner:HEFEI UNIV OF TECH

Weighing characteristic face recognition method for multichannel pulse coupling neural network

The invention discloses a weighing characteristic face recognition method for a multichannel pulse coupling neural network. The weighing characteristic face recognition method comprises the step 1, acquiring an original face color image, the step 2, converting the original face color image from an RGB color space to an HIS color space to obtain a converted face image, the step 3, respectively extracting three channels of data of the hue H, the saturability S and the illumination I of the converted face image, the step 4, using a PCNN technique to carry out iteration ignition treatment on the three channels of data of the H, the S and the I of the converted face image to generate three channels of pulse ignition ration sequences, the step 5, carrying out weighing treatment on the three channels of the pulse ignition ratio sequences and then connecting the weighed number sequences to form an overall pulse ignition ratio characteristic sequence spectrum of the converted face image, and the step 6, using the overall pulse ignition ratio characteristic sequence spectrum of the converted face image and a face sample sequence spectrum in a template base to carry out relevance match to recognize a right face image. The weighing characteristic face recognition method greatly improves the recognition rate of face images.
Owner:WUHAN UNIV

Improved soft output tail biting convolution code decoding method

The invention discloses an improved soft output tail biting convolution code decoding method. The method comprises the following steps of (1) acquiring a logarithmic likelihood ratio sequence; (2) calculating a branch metric; (3) calculating a forward metric; (4) calculating a backward metric; (5) calculating an information-bit logarithmic likelihood ratio to form the logarithmic likelihood ratio sequence; and (6) deciding. In the invention, the branch metric is calculated for one time, the forward metric and the backward metric are calculated for twice, and through using splicing, combination calculating is performed on a logarithmic likelihood ratio, a complexity is low and decoding performance is increased. In the invention, the information-bit logarithmic likelihood ratio sequence is calculated and is served as soft output, a tail biting convolution code can be served as an internal code which can carry out iteration with an external code in a whole system and an application value is expanded.
Owner:XIDIAN UNIV

Static correction method and device for converted S-wave

ActiveCN104914469ASolve the statics problemEasy to handleSeismic signal processingS-waveHorizon
The invention discloses a static correction method and a device for a converted S-wave. The method comprises steps: P-wave and S-wave speed ratio sequence scanning is carried out on acquired seismic wave data resources, and the optimal speed ratio is determined; according to the optimal speed ratio, a first time difference in the S-waves is calculated, and first-time static correction is carried out; an indicator horizon is picked on a P-wave stack section and a converted S-wave stack section; the indicator horizon is stretched to time corresponding to the converted S-wave stack section, a second time difference of the two stack sections is obtained, and second-time static correction is carried out based on the second time difference; the stretched P-wave stack channel serves as a model channel, a converted S-wave ACP channel collection at the corresponding position via two times of static correction correlates with the model channel, a third time difference between each channel in the ACP channel collection and the model channel is calculated, and third-time static correction is carried out. Additional material acquisition is not needed, a good S-wave first arrival is not required in the resources, and thus, large-scale production and processing are facilitated.
Owner:CHINA PETROLEUM & CHEM CORP +1

Polar code coding and decoding method for m-ary orthogonal spread spectrum signal

The invention discloses a polar code coding and decoding method for m-ary orthogonal spread spectrum signal, mainly solving the problem of poor bit error rate performance of m-ary orthogonal spread spectrum hard decision decoding in prior art and comprising the specific steps of: (1) reading an information sequence to be sent; (2) performing polar code coding on the information sequence; (3) performing interleaving processing on the polar code coding sequence; (4) performing m-ary orthogonal spread spectrum; (5) extracting a log-likelihood ratio sequence; (6) de-interleaving the log-likelihoodratio sequence; and (7) decoding the polar code. According to the soft-decision method of extracting the log-likelihood ratio sequence, the invention combines high-efficiency polar code coding and decoding with m-ary orthogonal spread spectrum, and has the advantages such as good error code performance, low complexity and high spectral efficiency, which meets the requirements of the channel coding and decoding technology for efficiency and reliability.
Owner:XIDIAN UNIV

Copula and Monte-Carlo simulation based path stroke time estimation method

The invention discloses a Copula and Monte-Carlo simulation based path stroke time estimation method. The method comprises the steps that S1) the fluctuation ratio of path stroke time of different segments in a path is obtained; S2) edge distribution fitting is carried out on the fluctuation ratio of path stroke time of different segments by means of maximum likelihood estimation; S3) a Copula theory is used to fit a path stroke time fluctuation ratio distribution function on the basis of a distribution function of the fluctuation ratio of path stroke time of different segments; S4) Monte-Carlo simulation is used to obtain a path stroke time fluctuation ratio sequence on the basis of the Copula function; S5) a confidence interval in certain confidence level is determined, and an expected value of the path stroke time fluctuation ratio is calculated; and S6) the expected value of the path stroke time fluctuation ratio is combined with path stroke time in the last period to estimate thepath stroke time of the present period. Sequential fluctuation of stroke time of the different segments as well as spatial relation between the segment stroke time is taken into consideration, time-space characteristic of the stroke time is dug deeply, and the precision and reliability are higher.
Owner:BEIHANG UNIV

Design wind speed analysis method and device for power transmission tower

The embodiment of the invention discloses a design wind speed analysis method and device for a power transmission tower, and can simultaneously consider a complex terrain influence and a typhoon-combined climate extreme value distribution characteristic tail deviation influence. The analysis method includes of 1, establishing a power transmission tower target position CFD terrain model; 2, selecting meteorological stations which have a certain of historical records and are distributed at the predetermined periphery in all the directions of the target position of the power transmission tower, obtaining the wind speed ratio sequence of the predetermined height at the predetermined incoming flow positions in all the directions of the target position of the power transmission tower and the predetermined height at the target position of the power transmission tower, and through the history records of the corresponding wind speed and wind direction of the corresponding meteorological stations, obtaining the extreme value wind speed sequence of the target position of the power transmission tower; 3, sampling in the extreme value wind speed sequence through an independent storm method to obtain extreme value wind speed samples, obtaining the probability density function of the mixed climate extreme value wind speed, calculating the parameters corresponding to the probability density function through a weighted least square method, and obtaining the extreme value wind speed in a discretional return period of the target position of the power transmission tower.
Owner:ELECTRIC POWER RES INST OF GUANGDONG POWER GRID

Method for predicting asset price trend, server and computer readable storage medium

The invention discloses a method for predicting asset price trend. The method comprises the steps of obtaining year-on-year sequence data of multiple types of assets corresponding to an observation moment; performing frequency domain filtering on the same-ratio sequence data of each type of assets according to the plurality of observation periods to obtain a filtering sequence of each type of assets in each observation period; merging the filtering sequences of the multiple assets in each observation period to obtain a filtering merging sequence corresponding to each observation period; inputting the year-on-year sequence data and the filtering merging sequence of each type of assets into a linear regression model to obtain regression parameters corresponding to each type of assets; and predicting the trend of the price of each type of assets according to the regression parameters and the filtering merging sequence corresponding to each type of assets. The invention further discloses aserver and a computer readable storage medium. The invention provides a method for obtaining asset trend information based on the economic cycle change rule of assets. The asset price trend can be accurately predicted.
Owner:JIANGSU SECURITIES

Method and apparatus for generating a phase-locked output signal

A method and apparatus for generating a phase-locked output signal includes generating an intermediate signal phase locked to an input signal by frequency dividing the intermediate signal by a temporally-varying divide ratio sequence to generate a first feedback signal and phase comparing the first feedback signal with the input signal. An output signal is generated phase locked to the first feedback signal by frequency dividing the output signal by the temporally-varying divide ratio sequence to generate a second feedback signal and phase comparing the second feedback signal with the first feedback signal.
Owner:ADVANTEST CORP

OFDM modulation system performance test method based on low peak-valley ratio sequence transmission

The invention belongs to digital transmission technology area. Its characteristic is: it put forward a new test model for the OFDM multi-carrier modulation system. This model sees the data stream from the inchoation of the modulation system and the data stream from the receiver as linear channel with the white Gaussian noise. Namely, we can describe the data stream from the inchoation x(n) and the data stream from the receive r(n) by r(n)=h(n)*x(n)+v(n). Here, '*' stand for linearity convolution operation. h(n) stand for test model channel's impulse response. v(n) stand for the linear convolution system's noise and the data disturbance. Propose a precise measuring model method according to this model. Its characteristic is that it carries on model parameter estimate when using LPVR testing system to transmit data.
Owner:TSINGHUA UNIV

Processing method and device for measured data of stable oxygen and hydrogen isotope ratio in water vapor

The invention discloses a processing method which is used for measured data of the stable oxygen and hydrogen isotope ratio in water vapor and is beneficial for eliminating errors generated when water vapor isotopes are determined with an isotope spectrometer. The method comprises the steps that the stable oxygen and hydrogen isotope ratios of specific water under multiple preset humidity values are measured with the spectrometer, and a first ratio sequence is obtained; the stable oxygen and hydrogen isotope ratio of the specific water under a specific humidity value is measured with the spectrometer; high-order polynomial fitting is conducted to obtain a humidity normalization formula for the spectrometer according to the first ratio sequence, the stable oxygen and hydrogen isotope ratios under the humidity values and the stable oxygen and hydrogen isotope ratios under the specific humidity value; a current humidity value and the stable oxygen and hydrogen isotope ratio under the current humidity value of measured water vapor are measured with the spectrometer; the stable oxygen and hydrogen isotope ratio of the measured water vapor under a humidity value normalized to the specific humidity value is obtained according to the normalization formula and the current humidity value and the stable oxygen and hydrogen isotope ratio under the current humidity value of the measured water vapor.
Owner:CHINESE ACAD OF METEOROLOGICAL SCI

Method for identifying fluctuation rub-impact fault of turbo generator set in real time

The invention discloses a method for identifying a fluctuation rub-impact fault of a turbo generator set in real time in the technical field of vibrational state monitoring and fault diagnosis of rotating machinery. The method comprises the following steps of: calculating and storing over-all vibration amplitude value data at intervals of one stepping length; after a first time length is reached,acquiring the maximum values of the stored over-all vibration amplitude value data; after a second time length is reached, arranging the maximum values of the over-all vibration amplitude value data to form an over-all vibration amplitude value extreme value sequence; solving the difference of the maximum value and the minimum value of the over-all vibration amplitude value extreme value sequence; calculating the ratio of every numerical value in the over-all vibration amplitude value extreme value sequence to the maximum value of the over-all vibration amplitude value extreme value sequence and forming a ratio sequence; calculating change peakness parameters of the ratio sequence, and the sum of the difference of the ratio sequence and the difference of the ratio sequence; and judging whether the axis of the set has the fluctuation rub-impact fault or not according to the obtained result. Real-time automatic on-line monitoring of vibration data of a bearing pedestal is realized, and efficiency and accuracy of fluctuation rub-impact fault real-time analysis of the turbo generator set are improved.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

Adjusting method of power spectrum estimation value and terminal

The invention provides the adjusting method of a power spectrum estimation value and a terminal. In the prior art, a direct current component in a power spectrum is difficult to completely eliminate.In the invention, the above problem is solved. The method comprises the following step of if a narrowband signal is included, adjusting the power spectrum estimation value of the second group of frequency points according to the average power spectrum estimation value of the first group of frequency points, wherein a frequency interval between each frequency point in the second group of frequencypoints and a target frequency point is greater than or equal to a first preset threshold and is less than or equal to a second preset threshold, the frequency interval between each frequency point inthe first group of frequency points and the target frequency point is greater than the second preset threshold, and the second group of frequency points includes a plurality of preset frequency pointswhich are adjacent to each other. In the invention, a power spectrum which does not contain the narrowband signal can be acquired, a purpose of eliminating the direct current component in the power spectrum is realized, the ranking of the effective frequency points in a power window ratio sequence can be increased and terminal full frequency band sounet time can be shortened.
Owner:DATANG MOBILE COMM EQUIP CO LTD

Method for identifying fluctuation rub-impact fault of turbo generator set in real time

The invention discloses a method for identifying a fluctuation rub-impact fault of a turbo generator set in real time in the technical field of vibrational state monitoring and fault diagnosis of rotating machinery. The method comprises the following steps of: calculating and storing over-all vibration amplitude value data at intervals of one stepping length; after a first time length is reached, acquiring the maximum values of the stored over-all vibration amplitude value data; after a second time length is reached, arranging the maximum values of the over-all vibration amplitude value data to form an over-all vibration amplitude value extreme value sequence; solving the difference of the maximum value and the minimum value of the over-all vibration amplitude value extreme value sequence; calculating the ratio of every numerical value in the over-all vibration amplitude value extreme value sequence to the maximum value of the over-all vibration amplitude value extreme value sequence and forming a ratio sequence; calculating change peakness parameters of the ratio sequence, and the sum of the difference of the ratio sequence and the difference of the ratio sequence; and judging whether the axis of the set has the fluctuation rub-impact fault or not according to the obtained result. Real-time automatic on-line monitoring of vibration data of a bearing pedestal is realized, and efficiency and accuracy of fluctuation rub-impact fault real-time analysis of the turbo generator set are improved.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING)

A Multistage Pulse Amplitude Modulator for Amplitude Equalization of Modulated Signals

The invention discloses a multistage pulse amplitude modulator with a function of achieving amplitude equalization of a modulation signal. The multistage pulse amplitude modulator comprises n Mach-Zahnder intensity modulators in series connection, wherein input ports and output ports of the Mach-Zahnder intensity modulators are connected end to end, and the input port of a first Mach-Zahnder intensity modulator is utilized as a light source input port, the output port of a final Mach-Zahnder intensity modulator is utilized as a modulation signal output port, and OOK signals with the same amplitude are loaded to each Mach-Zahnder intensity modulator, thereby achieving the modulation of 2N-stage pulse amplitude modulation signals; the effective modulation arm length ratio among the n Mach-Zahnder intensity modulators is 20 : 21: 22 : ... : 2N-1, and the arrangement sequence of the Mach-Zahnder intensity modulators with the above effective modulation arm length ratio does not limit to the above ratio sequence. According to the multistage pulse amplitude modulator with the function of achieving the amplitude equalization of the modulation signal, by improving the structure of the modulator, the flexible control of a phase bias point and the equalization of optical signals on the two arms of the modulator when the modulation signal is modulated are achieved, and the extinction ratio of the modulator is increased.
Owner:WUHAN POST & TELECOMM RES INST CO LTD

Ridge ratio shrinkage-based hyperspectral image virtual dimension estimation method

The invention discloses a ridge ratio shrinkage-based hyperspectral image virtual dimension estimation method. The method comprises the steps of extracting a sample matrix of a to-be-processed hyperspectral image; calculating to obtain a covariance matrix and a correlation matrix of the sample matrix, calculating characteristic values of the covariance matrix and the correlation matrix, and sorting; constructing a ratio sequence according to the characteristic value sequence; and comparing the sequence value in the ratio sequence with a preset constraint value to obtain a virtual dimension ofthe to-be-processed hyperspectral image. The estimation method abandons the idea of hypothetical inspection, and directly adopts an algorithm for constructing a ratio sequence to estimate, so that theaccuracy of the virtual dimension estimation of the hyperspectral image can be improved.
Owner:XI AN JIAOTONG UNIV

A method, apparatus and device for analyzing properties of a sample

The invention discloses a sample attribute analysis method, device and equipment, and belongs to the field of data analysis. The method comprises the following steps: determining the ratio Ri of samples of each attribute value according to the amount of the samples of each attribute value of the sample attributes of all samples and the overall sample amount; ordering all the attribute values of the sample attributes from larger to smaller so as to obtain the ratio sequence of the sample attributes [R1, R2, R3...Rn]; accumulating the ratio Ri of samples of each attribute value with the former ratio of samples of each attribute value R1, R2...Ri-1, so as to obtain a accumulated ratio Wi of each attribute value; confirming an advantage value I of the sample attributes according to the accumulated ratio Wi and the amount n of the attribute values, and taking the advantage value I as the analysis result of the sample attributes. According to the invention, the problems that a current sample attribute analysis method has higher requirement on analysis personnel, is stronger in subjectivity, low in treatment efficiency, large in resource consumption, and has no unified evaluation reference are solved, the analysis efficiency is improved, the working requirement on analysis personnel is reduced, and a unified evaluation reference is provided.
Owner:HUAWEI TECH CO LTD

Cell signal power measurement method

The invention discloses a cell signal power measurement method. The method comprises the following steps: receiving sample point-level synchronized data at a frequency point of a to-be-measured cell by a terminal; acquiring receiving training sequence frequency domain data and receiving training sequence time domain data from the received data; dividing local training sequence frequency domain data by the receiving training sequence frequency domain data to obtain a frequency domain ratio sequence; dividing the local training sequence time domain data by using the receiving training sequence time domain data to obtain a time domain ratio sequence; performing slipping autocorrelation on the frequency domain ratio sequence to obtain the frequency domain measurement power; performing slippingautocorrelation on the time domain ratio sequence to obtain time domain measurement power; and taking the greater value in the frequency domain measurement power and the time domain measurement poweras the cell signal power. Through the technical scheme disclosed by the invention, the influence on the cell signal power measurement by the timing deviation and frequency deviation can be effectively reduced, and the measurement precision is improved.
Owner:罗锦超

Data processing method and device

The invention discloses a data processing method and device. The data processing method comprises the steps: obtaining vehicle information corresponding to each designated road section in a pluralityof designated road sections, wherein the vehicle information comprises the vehicle violation absolute number and the vehicle traffic volume; for each designated road section, calculating according tothe vehicle violation absolute number and the vehicle traffic volume corresponding to the designated road section to obtain a traffic violation ratio corresponding to the designated road section; performing numerical value sorting on the traffic violation ratio corresponding to each specified road section in the plurality of specified road sections to obtain a traffic violation ratio sequence of each specified road section; screening out a plurality of specified road sections with large pass-to-violation ratio values in a first specified proportion from the pass-to-violation ratio sequence ofeach specified road section; and marking each screened specified road section as a violation high-incidence road section. According to the invention, the technical problem of how to determine the violation high-incidence road section in the related art can be solved.
Owner:车轮互联科技(上海)股份有限公司

Decoding processing method and decoder

Embodiments of the present invention provide a decoding processing method and a decoder. The method includes: acquiring a joint generator matrix Gcom of a turbo code generator matrix Gturbo and a cyclic redundancy check CRC generator matrix Gcrc, and acquiring the output of the turbo code decoder The log-likelihood ratio sequence of CRC; using the joint generator matrix Gcom and the log-likelihood ratio sequence, perform CRC-assisted iterative sorting and statistical decoding of the turbo code, and obtain the decoding processing result. The Turbo code decoding method and device provided by the embodiments of the present invention can improve the decoding performance gain.
Owner:HONOR DEVICE CO LTD

Unit ratio sequence-type transmission mechanism capable of being independently controlled

The invention relates to a unit ratio sequence-type transmission mechanism capable of being independently controlled. The unit ratio sequence-type transmission mechanism comprises a first planetary gear set, a second planetary gear set, an energy input end and a free transmission end, wherein the first planetary gear set comprises an energy output end; the second planetary gear set is connected to the first planetary gear set and comprises a control end; the energy input end is arranged on the second planetary gear set; and the free transmission end is arranged on the first planetary gear set, controlled by the control end and used for freely switching the free transmission end to be used as one of the energy input end and an energy output end. The unit ratio sequence-type transmission mechanism disclosed by the invention has the beneficial effect of improving the energy transmission efficiency.
Owner:SUN YAT SEN UNIV

An Improved Decoding Method of Tail-biting Convolutional Codes with Soft Output

The invention discloses an improved soft output tail biting convolution code decoding method. The method comprises the following steps of (1) acquiring a logarithmic likelihood ratio sequence; (2) calculating a branch metric; (3) calculating a forward metric; (4) calculating a backward metric; (5) calculating an information-bit logarithmic likelihood ratio to form the logarithmic likelihood ratio sequence; and (6) deciding. In the invention, the branch metric is calculated for one time, the forward metric and the backward metric are calculated for twice, and through using splicing, combination calculating is performed on a logarithmic likelihood ratio, a complexity is low and decoding performance is increased. In the invention, the information-bit logarithmic likelihood ratio sequence is calculated and is served as soft output, a tail biting convolution code can be served as an internal code which can carry out iteration with an external code in a whole system and an application value is expanded.
Owner:XIDIAN UNIV
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