33 results about "Space techniques" patented technology

Large scale sequences and other types of patterns may be matched or aligned quickly using a linear space technique. In one embodiment, the invention includes, calculating a similarity matrix of a first sequence against a second sequence, determining a lowest cost path through the matrix, where cost is a function of sequence alignment, dividing the similarity matrix into a plurality of blocks, determining local start points on the lowest cost path, the local start points each corresponding to a block through which the lowest cost path passes, dividing sequence alignment computation for the lowest cost path into a plurality of independent problems based on the local start points, solving each independent problem independently, and concatenating the solutions to generate an alignment path of the first sequence against the second sequence.

The invention provides a design method that can independently regulate the relative position of the two channels in a double-channel light filtering piece, adopting a bisymmetric structure based on Fabry-Perot etalon. It is different from traditional narrow-band light filtering piece in regulating independently the positions of the two channels by changing the thickness of several middle layers, respectively, and thus overcomes the position coherence phenomenon caused by the position regulation of channel. It introduces the design of the light filtering piece and concrete structure as well as the calculated spectrum characteristic of the double-channel band-pass light filtering piece, etc. It can be applied in the fields of optical detecting apparatus, space technique and so on.

A method of determining indicators for matrix codewords in a matrix codeword codebook, where the matrix codewords are adapted for communicating information between a transmitter and a receiver. The method includes providing a lookup table that is associated with multiple codewords that are associated with a codebook. The lookup table has m rows, and each row in the lookup table has a one-to-one correspondence with a codeword in the multiple codewords. Each row has p entries and each of the p entries holds a codeword indicator that identifies a codeword in the multiple codewords. The (i,j)th entry in the lookup table holds the codeword indicator identifying the jth most similar codeword to the codeword associated with the ith row according to a similarity metric, where 1≦i≦m and 1≦j≦p, and the m rows include a row k. The method includes identifying a first indicator in the row k by testing each of the indicators in the first p entries of row k to determine which of the indicators in the first n entries identifies a reduced search codeword that best satisfies a selection criterion, wherein, n has a predetermined value and 1≦n≦p, and, in relation to the other remaining indicators in the first n entries of the first row, the first indicator identifies the reduced search codeword that best satisfies the selection criterion.

The invention is applicable to the data mining field, and provides a random forest optimization method based on tensor decomposition. The random forest optimization method comprises the steps of: reading a training data set as an initial training set; acquiring a new training set based on the initial training set by adopting a preset random sampling method to form a random forest training set, wherein the random forest training set comprises a decision-making tree model trained by adopting a random sub-space technique; constructing a tensor model based o the decision-making tree model in the random forest training set; decomposing the tensor model by adopting a preset tensor decomposition technique; adjusting decomposed tensors to obtain adjusted tensors; selecting a decision-making tree subset with overall optimization from the adjusted tensors as an optimal base classifier subset; and utilizing a test sample set for testing the optimal base classifier subset. The invention further provides a Random forest optimization system based on tensor decomposition. The Random forest optimization method and the Random forest optimization system can obtain the random forest subset with the optimal overall performance.

Attenuation correction in SPECT studies such as cardiac function imaging is carried out using an iterative statistically-based transmission projection reconstruction algorithm that is capable of modeling overlapping transmission beams from a line source array of radiation emitters. Downscatter between emission and transmission photons is additively corrected for in the algorithm. Optimal line source spacing techniques and source collimation angle selection are derived to improve performance and reduce cost.

The invention discloses a time-varying system diagnosability quantification method under the influence of bounded interference, and belongs to the technical field of space. The method comprises: converting a spacecraft system described by a state space into a time stack dynamic model; converting a diagnosability quantification problem of the system into a full-symmetric polytope similarity calculation problem, giving mathematical definitions of system fault detectability and isolability, and quantifying diagnosability (including detectability and isolability) of the fault through a Hausdorff distance. Compared with an existing method, the method has the advantages that the spacecraft system model is popularized to the time-varying model from the existing time-invariant model, only the boundary of interference needs to be known, the specific form of interference does not need to be defined, actual engineering requirements are better met, and operation and execution of designers are facilitated.

A semi-physical testing system and method based on a high-orbit navigation compatible machine, belonging to the field of space technology. The invention proposes a semi-physical test method combining real GNSS antenna + GNSS simulator to solve the problem that high-orbit weak signals cannot be realistically simulated in the semi-physical test of high-orbit navigation compatible machines; at the same time, dynamics are realized by means of reflection memory network handshake The synchronous triggering of the upper computer and the GNSS simulator solves the problem that the measurement data of the high-orbit navigation compatible machine cannot be connected to the control closed loop in real time during the system-level semi-physical test.

The invention provides a design method that can independently regulate the relative position of the three channels in a triple-channel light filtering piece, adopting a triple-symmetrical structure on the basis of Fabry-Perot structure. It is different from traditional narrow-band light filtering piece in regulating independently the positions of the three channels by changing the thickness of several middle layers, respectively, and thus overcomes the position coherence phenomenon caused by the position regulation. It introduces the design of the light filtering piece and concrete structure as well as the regulating method and the calculated spectrum characteristic of the triple-channel band-pass light filtering piece, etc. It can be applied in the fields of optical detecting apparatus, space technique and so on.

A method for determining the reconfigurability envelope of a constrained system in a recoverable state domain belongs to the field of space technology. Through theoretical analysis and simulation verification, the present invention can give the maximum reconfigurability envelope of the spacecraft system under the constraint conditions of time and energy, realize the quantitative analysis of reconfigurability for the limited system, and can be used for optimization The spacecraft system configuration and fault-tolerant control algorithm realize the on-orbit monitoring of the health status of the spacecraft system and the autonomous processing of faults, and improve the autonomous reconfiguration capability of the spacecraft system. Compared with the existing methods, the patent of the present invention uses the fine integral algorithm to solve the reconfigurability envelope of the spacecraft system, which has the advantages of high precision, small amount of calculation, and easy implementation, and has sufficient flexibility and flexibility in practical applications. applicability.

The invention provides a design method that can independently regulate the relative position of the two channels in a double-channel light filtering piece, adopting a bisymmetric structure based on Fabry-Perot etalon. It is different from traditional narrow-band light filtering piece in regulating independently the positions of the two channels by changing the thickness of several middle layers, respectively, and thus overcomes the position coherence phenomenon caused by the position regulation of channel. It introduces the design of the light filtering piece and concrete structure as well as the calculated spectrum characteristic of the double-channel band-pass light filtering piece, etc. It can be applied in the fields of optical detecting apparatus, space technique and so on.

The invention relates to a method for obtaining fault detectability of a spacecraft system based on distance similarity, which belongs to the field of space technology. The method of the present invention is based on the vector-subspace distance, and considers the influence of unknown input on the system detectability, realizes the mathematical description of faults that are completely detectable and conditionally detectable, and greatly improves the accuracy of the results obtained by the detectability of the existing system sex. Compared with the existing methods, the method of the invention has a larger application range, sufficient flexibility and stronger applicability. Through the application on the control system, it is proved that the method is effective and feasible.

The invention relates to a spatial net-shaped antenna passive unfolding drive based on non-circular gears, and belongs to the technical field of space techniques. The spatial net-shaped antenna passive unfolding drive comprises a fixed frame, a pair of gear shafts, a pair of non-circular gears, two groups of straight toothed spur gears, linear planar spiral springs, circular groove frames and an output cylinder, wherein pitch curves of the non-circular gears are meshed with each other on the gear shafts; the straight toothed spur gears have provided transmission ratios; springs are mounted in the circular groove frames; the output cylinder is used for unfolding an antenna and used for driving a winding wire; the circular groove frames for mounting the springs are mounted on a shaft extending from a side surface of the fixed frame; the linear planar spiral springs are mounted inside the groove frames; the cylinder for driving the winding wire is mounted on a shaft extending from another side surface of the fixed frame; the non-circular gears are respectively fixedly connected with a standard gear on the innermost side of two groups of the straight toothed spur gear systems, rotate coaxially with the standard gear and work on the pair of the gear shafts. The spatial net-shaped antenna passive unfolding drive has the characteristics of simple structure and good engineering adaptability.

The invention provides a design method that can independently regulate the relative position of a pass band and two channels in a channel pass-band light filtering piece, adopting a triple-symmetrical structure based on Fabry-Perot etalon. It is different from traditional narrow-band light filtering piece in regulating independently the positions of a pass band and two channels by changing the thickness of several middle layers, respectively, and thus overcomes the position coherence phenomenon caused by the position regulation of the channel and pass band. It introduces the concrete structural design of the light filtering piece as well as the calculated spectrum characteristic of the one-channel two-pass band light filtering piece. It can be applied in the fields of optical detecting apparatus, space technique and so on.

The invention with its state-of-the-art and innovative methods has established a time simulation phenomenon pertaining to celestial objects independently for (14) Universal Time (FIG. 1). The co-ordination between three celestial objects Earth, Moon, and Sun are the significant sources for back mapping and the method remains immaculate and perfect in ascertaining the Universal Time Co-Ordination (15). The invention has delivered the classified integrity while implementing the most impressive and innovative methods in bringing-out a novel concept (9) and (10) for Universal Time Simulation. The Universal Time (14) and Universal Time Co-ordination phenomenon provide a leap ahead in worldwide clocks and time regulation in which clocks would be (7) self-synchronizing based on specific locations. The location-specific Time would be incorporated to have a reality-based transition in the framework of Universal Time and Universal Time Co-Ordination that would benefit watch manufacturing industry massively (7). The invented method also provides a framework for high-level precision clocks in research labs to check their integrity in timescale (16). The pioneered method in this present invention would benefit space industry to the maximum possible extent (FIG. 4) with its limited kernel (3) memory usage statistics. The singularity in the definition of Universal Time (14) would enhance simultaneous space mission programs.Universal Time and Universal Time Co-Ordination are key aspects in the following areas namely:Regulation of Clock and Time, World Wide Web, Network Time Protocol, International Broadcast, Weather Forecast, Air Traffic Control, Radio Stations, Space Technology.

A method and system for dynamic scheduling of heterogeneous equipment resources for remote sensing satellite receiving stations, belonging to the field of space technology. The present invention is realized through the following technical solutions: reconstruct all the parameters required for remote sensing satellite reception, and abstract a set of remote sensing satellite reception parameter templates; according to the characteristics of remote sensing satellite reception tasks, divide the equipment in the receiving station according to links, and complete Automatic matching of equipment resources and remote sensing receiving tasks; divide the equipment at all levels of the link into different types, build a driver interface for each type of equipment, and complete the flexible hot swap of equipment by adding drivers.

The invention is applicable to the field of space technology, and provides a satellite attitude determination method, device and terminal equipment. The method includes: acquiring the starry sky background image at the first moment and the starry sky background image at the second moment collected by the spaceborne camera; performing image matching on the starry sky background image at the first moment and the starry sky background image at the second moment , according to the matching result, determine the satellite attitude change value in the time period between the first moment and the second moment; obtain the satellite initial attitude one at the first moment obtained by the navigation system and the satellite initial attitude two at the second moment, according to the satellite The initial attitude 1, the satellite initial attitude 2 and the satellite attitude change value determine the satellite attitude at the second moment. The invention can determine the precise value of the satellite attitude with small error and high precision.

A highly reliable and high-frequency satellite wireless data acquisition system and method belong to the field of space technology. The invention includes a collection unit and several sensitive units, the collection unit communicates with the sensitive units through a wireless network; each sensitive unit includes sensitive components and at least four storage buffers. The frequency of the acquisition unit and the sensitive unit are different. The two-level frequency solves the contradiction between high-speed acquisition and large wireless delay. The four-area cache solves the problem of data loss and retake caused by wireless delay fluctuations. This method can be applied In the vibration measurement system of the large flexible body satellite and its components, the requirements of the flexibility identification algorithm are met, and the data is collected with high reliability and high frequency.