484results about How to "Improve conversion accuracy" patented technology

The invention relates to a multiturn absolute rotary encoder based on a rotary transformer, which is characterized in that: a sensor is displaced by taking the rotary transformer as a shaft angle; a shaft angle decoding circuit can be formed by adopting DSP as a core processor; a sine wave which can be controlled by frequency and phase in the method that the circuit is synthesized by direct digital frequency for the numerical control of an oscillator; and the sine wave is directly taken as an excitation rotary transformer signal via a power amplifier and a filter circuit; the rotary transformer signal is transferred to A/D converter after being run through a matching circuit of electronic transformer; after sampling, digital filtering and digital signal processing, the sine and cosine value for the actual angle of two channels is generated; the angle error change is tracked dynamically by the PI algorithm; the mechanical displacement of the rotating object is converted into digital shaft angle position and speed. The multiturn absolute rotary encoder based on a rotary transformer has the advantages of high tracking speed, high conversion accuracy, high reliability, simple structure, sensitive movement, low environmental condition, strong anti-interference capability, high measuring accuracy and speed voltage output.

The invention discloses a general multi-channel data collection system. The general multi-channel data collection system comprises a collection card and a master control card. The collection card collects analog signals transmitted from a collection sensor, and the analog signals are collected and converted into digital signals. The master control card carries out denoising and filtering on data in the digital signals, so that real-time correction of the data is achieved, an upper computer is connected with the master control card, and configuration information is written from the master control card, so that control over the work of a whole system is achieved. An analog-digital conversion module of the collection card converts the analog signals into the digital signals, and a photoelectric isolation module of the collection card isolates the analog portion from the digital portion of the whole data collection system completely, so that the transmission of the analog signals is not interfered by noise of a digital circuit. The photoelectric isolation module is used for reducing the influence of the noise of the analog portion on the digital portion, a precision power module of the collection card reduces the influence of power supply noise, and a phase-locked loop of the collection card guarantees phase synchronization of clock signals among the collection cards.

In a color converting device for converting input image data based on a plurality of first color components (the number of bits of each color component is k) into output image data based on plural of second color components by interpolation processing using a 3DLUT storing color correction values at grid points obtained by dividing a color space composed of the plurality of first color components, the distance of the grid points is 2ⁿ (where n is an integer smaller than k), the number Dn of grid points of the plurality of first color components is an integer satisfying 2^m−1+1<Dn<2^m+1+1 (where Dn≠2^m+1, and m=k−n), and input image data is converted into output image data by converting each color component data of the input image data according to the number of grid points, and performing interpolation processing by reading color correction values corresponding to the converted color components from the 3DLUT.

The invention relates to a LED constant current drive circuit with light dimming function, comprising a LED constant current supply circuit, an analog LED current regulating circuit and a digital LED current regulating circuit. The invention has the improvement that the digital LED current regulating circuit comprises a pulse width measuring circuit for a digital light-dimming signal and a D/A converter converting a pulse width attribute output by the pulse width measuring circuit into an analog voltage value. The invention uses the pulse width measuring circuit and the D/A converter to convert a digital light-dimming PWM signal into an analog signal, and then the analog signal is sent to an analog light-dimming input end to carry out analog light dimming; thus, the digital light dimming of the LED constant current drive circuit has the same light-dimming efficiency with analog light dimming, which solves the problem of low efficiency of digital light dimming. Simultaneously, the invention also has the characteristic of high light-dimming precision by further improvement.

The invention provides a fine structure deformation monitoring method based on ground three-dimensional laser scanning. The method comprises steps that, a GPS or a total station is utilized to arrange artificial target points, and a target point monitoring net is established; point cloud data at a surface of a structure at different moments are acquired by utilizing a ground three-dimensional laser scanner; data acquired by the target point monitoring net and data acquired by the ground three-dimensional laser scanner are converted to a same reference coordinate system; the data in the same reference coordinate system are utilized to determine and fit a geometrical model of the structure; point cloud data segmentation is carried out according to the geometrical model of the structure obtained through fitting, the point cloud data segmentation is divided into multiple parts, and each part is fitted into one representative point; change of coordinates and vectors of the representative points obtained through point cloud data fitting at different moments are contrasted to carry out fine structure deformation analysis. The fine structure deformation monitoring method can realize monitoring on fine structure deformation.

The invention relates to a high temperature creep life accelerated test method of a material, which comprises: a plurality of groups of short time stress relaxation tests of the material at the same temperature, acquiring a relaxation rate-stress curve based on the numerical differentiation principle, forming a relaxation creep rate-stress curve by utilizing a relaxation equation, calculating creep data to build a creep curve, and building a steady state creep rate curve and a Norton creep equation. The method starts from the physical relation between relaxation and creep, covers rather broad properties of creep strain rate by utilizing the short time relaxation process, and educes broader creep data than that educed from general creep tests by above ten times, thereby effectively reducing the amount of high temperature creep tests and time of tests and providing basic data for development of new material and engineering application.

The invention discloses a 1553B bus monitoring and data analysis system. The 1553B bus monitoring and data analysis system comprises a board card interface module, a thread scheduling module and a man-machine interaction interface module. The board card interface module comprises a board card initialization module, a starting/stopping receiving control module, an interrupt processing module, a data acquisition module and a failure recording module. The thread scheduling module is provided with a data monitoring storage thread, a data analysis thread, a data display thread and a message loop main thread. The man-machine interaction interface module is provided with a user authentication and management module, a monitoring mode setting module, a monitoring starting and stopping setting module, a data conversion setting module, a conversion starting and stopping setting module, a data memory module and a data list display module. According to the 1553B bus monitoring and data analysis system, a thread dynamic scheduling algorithm is adopted, comprehensive monitoring of bus data and real-time storage, display and analysis conversion of MT monitoring data can be achieved, and display of bus monitoring information stored in a specific format and conversion processing of stored data can also be achieved.

An on-line analyzing and detecting device of coal quality is prepared as shining sample to be analyzed by laser to generate induced light spectrum; collecting said spectrum by CCD image transducer and image collection control circuit and calculating to obtain vector E of character element content in raw coal by signal processor; sending vector E into BP neural network for carrying out conversion to obtain heating value, water content, ash content, volatile composition and fixed carbon of raw coal; utilizing neural network to predict slagging index and temperature of ash melted point of raw coal.

The invention provides a natural language query interface achievement method oriented to big data. Chinese natural language query is converted into an SQL or BSON transformation strategy, semantic depending trees are generated according to natural languages, then the semantic depending trees are converted into query trees according to established rules, and BSO sentences of SQL and NoBSON corresponding to the natural languages are obtained by parsing the query trees. The method supports corpus extension and improves the conversion accuracy in the given field. In addition, NoSQL conversion nodes are increased, and the application range of the method is widened.

A D/A conversion circuit includes a first D/A converting section which is connected with an output node, a first serial capacitor which is disposed between the output node and a first node, a second D/A converting section which is connected with the first node, and a control circuit. The first D/A converting section includes a first capacitor array section and a first switch array section. The second D/A converting section includes a second capacitor array section and a second switch array section. The control circuit performs a switch control for dynamically changing allocation of the capacitors to the respective bits of input digital data for the first switch array section of the first D/A converting section.

When an sRGB color space and an wRGB color space have a common white point in a device-independent color space, the CPU 31 of a color printer 20 eliminates deviation of the white points of the two color spaces occurring when a color value of the sRGB color space has been converted to a color value of the wRGB color space using a matrix operation L, by correcting the coefficients of matrix L. As a result of correction a matrix L′ is obtained. CPU 31 executes gamma correction on the RGB color space color value obtained by a matrix operation S, and then executes matrix operation L′. CPU 31 executes inverse gamma correction on the color value obtained by a matrix operation L′.

An A/D converter circuit includes first to fourth pulse circulation circuits and first and second counters and configured to provide high conversion accuracy irrespective of a temperature change. The first pulse circulation circuit operates with a difference voltage of a specified voltage and an analog input voltage. The first counter outputs a difference of the number of pulse circulation in the first and the second pulse circulation circuits. The third pulse circulation circuit operates with a difference voltage of the specified voltage and a set voltage. The fourth pulse circulation circuit operates with the set voltage. The second counter outputs a difference of the number of pulse circulation in the third and the fourth pulse circulation circuits. When an output value of the second counter reaches a specified value, an output value of the first counter at that time is outputted as A/D conversion data.

The invention relates to a method for converting creep data into material high-temperature stress relaxation data, which comprises the following steps: a method and a step for acquiring the material creep property data of a high-temperature component material at certain temperature and performing normalization processing on the material creep property data, a method for dividing the process of relaxation, and a process of creep-relaxation conversion. The method comprehensively considers the influences at different creep stages, improves the precision of data conversion from creep to relaxation, can acquire the relaxation property data satisfying the design requirements on engineering structures, and can be expected to replace relaxation tests having high requirements on experimental installations.

The invention discloses a weight calibration method for a non-binary successive approximation type analog-digital converter, the non-binary successive approximation type analog-digital converter comprises a capacitor array and a virtual capacitor C0, the capacitor array comprises n capacitors, and n capacitor values from the largest to the smallest are Cn, Cn-1, Cn-2, Cn-3 toC1, and C1 is equal toC. According to the weight calibration calculation method of the mth capacitor, the redundant weight Rm of the mth capacitor is larger than 0, and the mth capacitor refers to the mth capacitor with the capacitance value from low to high in the capacitor array. The invention provides a weight calibration method for the non-binary successive approximation type analog-to-digital converter. Sequential control logic optimization is carried out on sampling and conversion process so that the digital logic of the calibration algorithm is simplified, only the accumulation average process is carried out. Meanwhile, the method has a faster operation result, and only one quantization error is introduced when noise is small.

The invention discloses a full-automatic collecting liquid-plastic limit combined measuring system. The full-automatic collecting liquid-plastic limit combined measuring system comprises a liquid-plastic limit combined measuring instrument and a computer, wherein the liquid-plastic limit combined measuring instrument comprises a mounting frame, a cone head, an electromagnet, a displacement transducer, a displacement display screen, a CPU (central processing unit), a communication module, a control switch and a specimen cup; the specimen cup is placed on the mounting frame; the electromagnet, the displacement transducer, the displacement display screen, the CPU, the communication module and the control switch are arranged on the mounting frame; the cone head is arranged above the opening of the specimen cup and is adsorbed on the electromagnet; the displacement transducer is connected with the computer in a signal manner through the CPU and the communication module; and a double logarithmic chart is stored in the computer. The full-automatic collecting liquid-plastic limit combined measuring system provided by the invention can be used for acquiring, measuring and reading data in a full automatic manner and drawing a curve, so that the accuracy of the test data is improved, the work amount of experimenters is reduced, the cost of human resources is reduced, and the test efficiency is improved.