49 results about "Latin square" patented technology

A base station having the strongest downlink signal is identified by utilizing a unique slope of a pilot tone hopping sequence being transmitted by a base station. Specifically, base station identification is realized by determining the slope of the strongest received pilot signal, i.e., the received pilot signal having the maximum energy. In an embodiment of the invention, the pilot tone hopping sequence is based on a Latin Squares sequence. With a Latin Squares based pilot tone hopping sequence, all a mobile user unit needs is to locate the frequency of the pilot tones at one time because the pilot tone locations at subsequent times can be determined from the slope of the Latin Squares pilot tone hopping sequence. The slope and initial frequency shift of the pilot tone hopping sequence with the strongest received power is determined by employing a unique maximum energy detector.

Base station identification and downlink synchronization are realized by employing pilots including known symbols transmitted at prescribed frequency tones in individual ones of prescribed time intervals. Specifically, the symbols used in the pilots are uniquely located in a time-frequency grid, where the locations are specified by periodic pilot tone hopping sequences. In a specific embodiment of the invention, a period of a pilot tone hopping sequence is constructed by starting with a Latin-square based hopping sequence, truncating it over time, and possibly offsetting and permuting it over frequency. Particular examples of pilot tone hopping sequences are parallel slope hopping sequences in which the periodicity of the sequences is chosen to be a prime number of symbol time intervals. In another embodiment of the invention, a notion of phantom pilots is employed to facilitate use of various system parameters while accommodating the above noted pilot tone hopping sequences.

A method and an apparatus for transmitting a reference signal in a wireless communication system are provided. A first base station maps a first reference signal to a resource region and transmits the first reference signal to a user equipment. A second base station maps a second reference signal to said resource region and transmits the second reference signal to said user equipment. The resource elements, to which the first reference signal and the second reference signal are mapped in the resource region, are determined in accordance with the index on a Latin square matrix occupied by two different elements, respectively, from among N elements constituting the Latin square matrix with a size of N×N.

A system and method for implementing a lottery game that correlates a first and second sequence of indicia, such as by pairing each term in the first sequence with the term in the second sequence in the same relative position. The correlation is subsequently mapped to a third set of indicia by the game process. For example, the game process may be a Latin square for which each term in the first sequence is identified with a row and each term in the second sequence is identified with a column (or vice versa) and the entries of the square are elements of a third set. Prizes are determined based on the properties of the third set of indicia, such as the number of occurrences of a particular symbol. The entertainment value lies in the various correlating and mapping.

The invention discloses a matrix-model-based software testing method. The matrix-model-based software testing method comprises the following steps: a) dividing a software system according to function modules; b) splitting and combining the function modules to form layer-level function test points; c) establishing a test case set by structuring a covering matrix for all layer-level function test points, so that each valid value of any pair of input parameters in each level of function test point is coated with at least one test case, wherein in the step c), for the function test point with less than or equal to three input parameters and valid values, the two-coverage test case set is directly established by Latin square. In the matrix-model-based software testing method, by extracting the function test points and matrixing the function test points, the optimal test case set is obtained through matrix calculation, so that the coverage rate, the testing efficiency and the testing accuracy can be improved all around, a testing need of a large software system can be met and the testing cost can be reduced.

The invention discloses an automobile hub lightweight design method. The method comprises the steps of S1, establishing an automobile hub three-dimensional geometrical model and filling the spoke area of the geometrical model with materials; S2, establishing a hub topology optimization mathematical model and obtaining the optimal material distribution structure of a hub by means of topology optimization; S3, conducting secondary design and strength analysis in CAD software according to the hub structure subjected to topology optimization; S4, establishing an approximation model by means of the Latin square test sampling method and the response surface technology, and conducting size optimization on the hub subjected to secondary design by means of the evolution algorithm; S5, conducting strength verification on the optimized model. According to the method, conceptual design is conducted on the automobile hub firstly through topology optimization to obtain optimal material structure distribution of the automobile hub, then the approximation model is established by means of the Latin square testing method and the response surface technology with the strength of the hub as the restraint condition, detailed size optimization is conducted on the hub subjected to secondary design by means of the evolution algorithm, and then lightweight of the hub is realized.

A check matrix generating apparatus calculates a parameter for pseudo-random-number permutation matrices using a predetermined information length, a coding rate, and a maximum column degree, generates the pseudo-random-number permutation matrices from the calculated parameter for the pseudo-random-number permutation matrices by using a pseudo-random-number sequence and a Latin square matrix, determines, as a parameter, a combination of degree distributions which can be adopted for optimization of a degree distribution of generation of a check matrix which can be formed with the pseudo-random-number permutation matrices, using the predetermined information length, coding rate, and maximum column degree, optimizes the degree distribution of generation of a check matrix under a restriction condition based on the determined combination of degree distributions which can be adopted, and arranges the generated pseudo-random-number permutation matrices according to the optimized degree distribution of generation of the check matrix so as to generate the check matrix for low-density parity-check codes.

A method and apparatus for parallel structured Latin square interleaving in a communication system are provided. The method includes dividing input information bits into sub-blocks according to a parallel processing order, generating a first Latin square matrix or a second Latin square matrix by comparing the parallel processing order with a predetermined threshold, and interleaving by reading out the information bits divided into the sub-blocks according to the generated Latin square matrix.

The invention discloses a natural laminar flow nacelle appearance determination method and system. The method comprises the following steps of: parameterizing a section of a to-be-improved nacelle byadoption of a CST method, and obtaining a position of a transition of the natural laminar flow nacelle through a gamma-Re theta transition model; obtaining boundary conditions of an air inlet and an engine outlet; obtaining variable groups by adoption of a Latin square design method; obtaining corresponding nacelle resistance according to the variable groups; establishing a first Kriging responsesurface model; obtaining a variance of the nacelle resistance corresponding to the variable groups; establishing a second Kriging response surface model; determining a target function, and predictinga mean value and a variance of the nacelle resistance by utilizing the first Kriging response surface model and the second Kriging response surface model; obtaining a variable group which enables a function value the target function to be the minimum, so as to obtain an optimal variable group; determining an appearance of the natural laminar flow nacelle according to parameters in the optimal variable group. The method and system are capable of effectively improving the performance of appearances of laminar flow nacelles, decreasing the skin friction resistance of airplanes and improving the economic efficiency of the airplanes.

The invention relates to a color image encryption method based on Latin square scrambling. Plaintext keys r1, g1 and b1 are calculated through utilization of R, G and B components of a color plaintextimage, an initial value and a parameter obtained through calculation based on the keys are substituted into a chaotic system, and three groups of chaotic sequences are generated; the chaotic sequences for scrambling and diffusion are selected through utilization of a chaotic sequence selection mechanism based on the plaintext and digital arrangement; and a final ciphertext image is obtained through adoption of a block scrambling policy based on a Latin square and the chaotic sequences, and diffusion operation based on the plaintext and a scrambled image. The encryption method is closely related to the plaintext, so the plaintext attack resistance is improved. The employed chaotic system is an improved chaotic system, a chaotic characteristic is good, the randomness is high and a key spaceis great, so a security level is further improved. A simulation result and safety analysis show that according to the encryption provided by the invention, an image complete encryption demand can besatisfied, the encryption efficiency is high, and the robustness is high.

The invention discloses a microarray lattice method for a biological chip. According to the method, quasi-Latin square experimental design is adopted and is divided into three kinds: 1, quasi-Latin square array lattice design in sub squares; 2, quasi-Latin square array lattice design among the sub squares; and 3, quasi-Latin square array lattice design in the sub squares and among the sub squares. By the microarray lattice design of the biological chip, space effect error caused by different factors can be avoided and eliminated to a certain degree, and the accuracy of biological experiments or experimental results is improved to a certain degree.

A method for generating Latin square family sequence includes obtaining expansion Latin square family matrix with multiple column expansion Latin square family sequence by carrying out expansion on Latin square family matrix generated according to set prime number and parameter, furthermore realizing frequency hopping communication control on frequency hopping point number being nonprime number according said expansion Latin square family sequence when frequency hopping point number is non-prime number.

The invention discloses a generalized perception model under limited spectral resources and a distributed Q learning access method. According to the model, a channel perception mechanism based on a zero-added latin square matrix is proposed by considering limitation of spectrum resources and dynamism of network environment and aiming at the problem of multiple time-slot channel perception sequenceoptimization. The method includes the following steps that firstly, a game model is constructed, and participants are all cognitive users in a network; based on the generalized perception model, eachuser randomly selects a channel perception sequence strategy from the corresponding zero-added latin square matrix and conducts perception; each active user calculates a current state return value and conducts Q-value update and probability update for the next time slot on the basis of the current state return value; the cognitive users conduct time-slot perception circularly until channel perception sequence strategies of all the cognitive users are converged. By adopting the model and the method, multiple time-slot channel perception sequence conflict is effectively reduced under the limited spectral resources, and handling capacity of the system cognitive users is improved.

Method and System for evaluating a turbo-coding scheme suitable for VDSL2 systems. The scheme is a Turbo-Trellis Coded Modulation TTCM that makes use of a Parallel Concatenated Convolutional Code (PCCC) including an inner Latin square / rectangular matrix of Random sequence pattern Interleaver (LRI) of approximately 2044 bits. In the presence of the outer Reed Solomon Code but without an outer interleaver (fast mode), the method and system provides 7.1 dB of average net coding gain, i.e., 2.6 dB of coding gain improvement relative to the standard 16 states 4-dimensional (4-D) trellis code used in current ADSL2 systems. The substantial coding gain achieved through the method and system, leads to an increase in the VDSL2 rate by 38% at 6 kft against local exchange carriers, such as ILEC (SBC) conditions with approximately 1.5 ms of latency. By encoding only two bits per tone (i.e., 1 bit per dimension), the turbo code implementation complexity is kept reasonable. Finally, the coded modulation scheme supports very small constellations, allowing transmitting spectral efficiency as low as 0.5 bit / sec / Hz over Binary Phase Shift Keying (BPSK) constellations at a signal-to-noise-ration (SNR) very close to the Shannon bound.

The invention relates to a multi-path communication method based on secret sharing in a vehicle-mounted ad hoc network environment, which comprises the following steps: finding a plurality of disjointpaths between a starting node and a target node by utilizing a Latin square matrix, and dividing a symmetric encryption key into a plurality of sub-keys by utilizing secret sharing. Meanwhile, the encrypted message is also divided into a plurality of parts, an equivalent commitment is generated for each sub-key to support fault tolerance, and meanwhile, a current timestamp is selected to resist areplay attack, the encrypted sub-key, the ciphertext and the commitment are jointly transmitted to the target node through each path,the target node reconstructs a key by using the sub-key, and decrypts the ciphertext by using the key to obtain an original message. According to the communication method, the network load is greatly reduced, the information transmission efficiency is improved, andmeanwhile the communication method has the advantages of being good in stability and not prone to being attacked or stealing private data. The communication method also has high fault tolerance, andcan provide normal service even when unstable factors such as network congestion, flow limitation and node equipment damage occur.

A method and apparatus are disclosed for parallel all-mass tandem mass spectrometry employing multi-reflecting time-of-flight analyzer for both MS stages, preferably arranged within the same analyzer to secure ultra-high resolution. Sensitivity and speed of TOF-TOF tandem are enhanced by non-redundant multiplexing based on signal sparseness and on avoiding repetitive signal overlaps at multiple repetitions of true fragment signals. Non-redundant matrices of gate and delay timing are constructed by extending orthogonal Latin square matrices. The method is generalized for multiplexing of any multiple repetitive signal sources being sparse either spectrally, or spatially, or in time.

The invention relates to a building instantaneous cold load prediction method based on a Monte Carlo method using Latin hypercube sampling. The method comprises: using a Monte Carlo simulation methodto calculate a building cold load, and using the Latin hypercube sampling method to perform random sampling of the Monte Carlo simulation method; the Monte Carlo simulation method being a numerical calculation method guided by a probability statistics theory, performing random sampling on all uncertain parameters forming the building cooling load, recombining samples of all the uncertain parameters, and obtaining probability distribution of the building instantaneous cooling load after multiple times of Monte Carlo simulation. In the statistical sampling process, the Latin hypercube is the popularization of a Latin square matrix in multiple dimensions, each hyperplane perpendicular to the axis contains at most one sample, and therefore the Monte Carlo simulation frequency is reduced whilethe randomness of the samples is guaranteed. According to the method, the building instantaneous cooling load can be effectively calculated and predicted, and a reference basis is provided for installation and model selection of the building air conditioning system and operation optimization of the air conditioning system.

The present invention relates to a method to build 3-dimensional models of molecular structures corresponding to the lowest value of the potential energy function from knowledge of their chemical structures. The system uses Mutually Orthogonal Latin Squares to search through conformational space to obtain the best conformation. The system may also be used to obtain the optimum of any function, and not only those related to biomolecular structure.

The invention provides an image encryption method based on a 3D orthogonal Latin square and a chaotic system. The method comprises the steps of 1, preprocessing a plaintext image P to obtain a preprocessed image P2; wherein the preprocessing comprises the steps that a 4D memristor chaotic system is utilized to generate a random number sequence according to the information entropy of the plaintextimage P, the random number sequence is embedded into the plaintext image P to obtain an embedded image P1, and letter XOR operation is carried out on the embedded image P1; 2, generating a 3D orthogonal Latin party according to the index sequence and the control parameters; and step 3, converting the preprocessed image P2 into a 3D bit matrix, and performing scrambling operation and diffusion operation on the 3D bit matrix by using the 3D orthogonal Latin method to obtain a ciphertext image corresponding to the plaintext image P. The method solves the problems that a scrambling method is invalid for special image scrambling and low in algorithm efficiency, is highly sensitive to plaintext images, can effectively resist known plaintext and selected plaintext attacks, and has high safety performance.

A system and method for implementing a lottery game that correlates a first and second sequence of indicia, such as by pairing each term in the first sequence with the term in the second sequence in the same relative position. The correlation is subsequently mapped to a third set of indicia by the game process. For example, the game process may be a Latin square for which each term in the first sequence is identified with a row and each term in the second sequence is identified with a column (or vice versa) and the entries of the square are elements of a third set. Prizes are determined based on the properties of the third set of indicia, such as the number of occurrences of a particular symbol. The entertainment value lies in the various correlating and mapping.

The invention provides a binary linear transformation method for a diffusion layer in substitution-permutation network block encryption. The method mainly comprises the following steps of: transforming an 8-order Latin square to form a binary matrix, the Hamming weights of each row and each list of which are 8*8 of 5; and then detecting whether the matrix meets linear independence of random 3 lists, if passing the test, detecting whether the test of the matrix is reversible, if so, judging the matrix as a proper matrix. The invention provides a new binary linear transformation method for the diffusion layer in the substitution-permutation network block encryption; and the method has the advantages of simple implementation logic and high running efficiency, and meanwhile does not lose the attack resistance of a code structure.

The invention relates to mobile beehive communication technology, specially a disturbing latin square group sequence generating method and device and frequency hopping communication control method and system. The disturbing latin square group sequence generating method and device provided in the invention uses disturbing sequence to disturb rule of element in current latin square group, and generate even sequence of bigger element and smaller element, obtain the disturbing latin square group sequence. The frequency hopping communication control method and system uses disturbing latin square group sequence to proceed frequency hopping communication control, within short period, realize even frequency hopping control, and improve effect of frequency diversity.

A circular logic puzzle The “CIRCULAR” puzzle has similarities to Sudoku and Latin squares in problem solving, and in this new circular format the many different varieties of game play and playing surfaces can be produced gives many new challenges and perspectives for those who enjoy solving logic puzzles.

The invention discloses a coding and decoding method for a rateless Spinal code based on a Latin square. The method comprises the following steps of generating an initial sequence; generating a statesequence; coding the state sequence by using a repeated Hadamard matrix; generating a parity bit sequence; generating all possible state code block sets; generating a possible initial code block; generating a full-connection grid diagram; decoding all possible state code block sets; selecting a decoding result by a decoder; judging whether a decoding sequence is the same as the initial sequence ornot; and outputting the decoding sequence selected by the decoder. According to the method, the Latin square is used for mapping each initial code block in the initial sequence and one adjacent initial code block into one state code block having the same length as the initial code block, so that the decoding calculated amount is reduced, the decoding complexity is reduced, and the decoding efficiency is improved.

A parallel information processing apparatus includes a group of switches configured to have a topology of a Latin square, and nodes connected with a switch among the group of switches. The parallel information processing apparatus also include a memory and a processor configured to designate (n×k) units of blocks in the group of switches included in a lattice structure in the topology of the Latin square; to generate information about communication protocol that includes communication directions having different slopes for m (m≦k) units of the nodes, and the number of hops set for the respective communication directions having the different slopes; and to execute communication for the m units of the nodes of the units of the block, based on the information about communication protocol, so as to execute part-to-part communication between the m units of the nodes of the respective units of the blocks.

The invention provides a Latin square-based chaotic image encryption method, which comprises the following steps of: generating a key by using an original image matrix, and inputting the key into a hyperchaotic Lorenz system to obtain a chaotic sequence; intercepting the chaotic sequence, converting the chaotic sequence into a matrix, and scrambling an original image matrix; intercepting the chaotic sequence to generate a Latin square matrix as a lookup table; intercepting the chaotic sequence and forming an index matrix, and selecting elements from corresponding coordinates in the lookup table by using the index matrix for replacement to obtain a pixel replacement matrix; and intercepting the chaotic sequence and generating a Latin square matrix, forming a bit matrix by using bit planes of the pixel replacement matrix, performing bit scrambling on the bit matrix by using the Latin square matrix, combining the bit matrix and the Latin square matrix into a bit plane matrix, and converting the bit plane matrix into a decimal system to obtain a ciphertext image. Latin square matrices used in the method are all generated by chaotic sequences, so that the complexity is enhanced, and the safety is improved; the randomness and the sensitivity are effectively improved, differential attacks can be effectively resisted, the decoding difficulty is increased, and the method is suitable for practical application.

A predetermined information length, a predetermined coding rate and a predetermined maximum order of the column are used to calculate parameters for a pseudo random number permutation matrix. The calculated parameters for the pseudo random number permutation matrix are used, with a pseudo random number sequence and a Latin square matrix, to produce the pseudo random number permutation matrix. A predetermined information length, a predetermined coding rate and a predetermined maximum order of the column are used to calculate parameters for possible order distribution combinations for optimizing the order distribution of production of a check matrix that can be constructed by use of the pseudo random number permutation matrix. The order distribution of the check matrix production is optimized with the calculated possible order distribution combinations used as forced conditions. The optimized order distribution of the check matrix production is used to arrange the produced pseudo random number permutation matrix to produce a check matrix to be used for low-density parity check codes.

The invention provides a method of determining transmission time-frequency resources of traffic data in a wireless communication network. The network device determines a time-domain transmission pattern Pi, j of the traffic data from a time-domain transmission pattern set PI, J; determines a frequency hopping pattern of the traffic data based on a frequency hopping matrix and a first rule, wherein the frequency hopping matrix is constructed by one or more Latin squares, a number of rows of the frequency hopping matrix is equal to a number of sub-bands in a frequency hopping bandwidth, each element in a row of the frequency hopping matrix successively represents a frequency hopping order of the complement transmission patterns Pi, j and Pi, j′, a number of columns of the frequency hopping matrix is equal to a number of transmissions of the traffic data, and the first rule is Pi, j and Pi, j′ are assigned with a same channel within a sub-band and a value of j is a part of J or all of J, the complement transmission patterns Pi, j and Pi, j′ in the transmission pattern subset Pi, J are assigned with a same channel within a sub-band and use a same sub-band for their first transmission, the non-complement transmission patterns Pi, j and Pi, k in the transmission pattern subset Pi, J have a same relative location in each sub-band and the non-complement transmission pattern subsets Pi, J and Ps, J are assigned with the different channels within a sub-band; and sends the traffic data according to the time-domain transmission pattern Pi, j and the frequency hopping pattern.