Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

131 results about "Low latitude" patented technology

Low latitudes. The Southern Hemisphere low latitudes are considered to be the areas of the earth south of the equator and north of about 30 degrees latitude.

Medium and low orbit constellation satellite beam frequency resource allocation method

The invention provides a medium and low orbit constellation satellite beam frequency resource allocation method. The medium and low orbit constellation satellite beam frequency resource allocation method comprises the steps of: performing initial sub-band allocation on each beam, and taking a certain fixed carrier in the sub-band allocated by each beam as the carrier of a broadcasting channel, wherein the initial sub-band of each beam is at least a sub-band; according to the odd number or even number of the orbit planes of the satellite constellation, determining a main orbit plane and a supplementary orbit plane; realizing coverage of partial areas to the ground including the two poles through single coverage composed of a satellite in the main orbit plane, and performing beam opening orclosing on the satellite in the supplementary orbit plane, so that the coverage of a blank area to the ground at the medium and low latitudes is completed; performing frequency resource allocation oneach terminal by taking the carrier as the unit, and, if the number of access terminals under a certain beam is beyond the user number born by the initial sub-band, increasing available sub-bands or carriers for the satellite beam; and realizing complete coverage. By means of the medium and low orbit constellation satellite beam frequency resource allocation method in the invention, constellationbeam frequency resource allocation can be realized better; and the method has the characteristics of being simple, high-efficiency and high in engineering practicability.
Owner:BEIJING SATELLITE INFORMATION ENG RES INST

Semi-opening greenhouse cultivation technology for peach tree in low-latitude plateau area

The invention relates to a semi-opening greenhouse cultivation technology for a peach tree in a low-latitude plateau area. The technology is characterized in that a greenhouse frame is arranged on one surface of a greenhouse; a layer of inspect proof nets and a layer of heat preserving quilts sequentially cover the frame; the heat preserving quilts are controlled by a contracting and stretching bracket to the contracted and stretched, and therefore, the temperature in the greenhouse of the peach tree can be controlled in different growth periods and under the changeful air temperature condition at the low-latitude plateau area; meanwhile, the technologies like the water and fertilizer control technology and the special fruit bag utilizing technology are adopted, thus the damage factor under the natural condition is removed, and the natural growth state of the peach tree is remained to the maximum; the applied pesticide is about 20% that under the common planting condition, the applied chemical fertilizer is about 30% that under the common planting method, the water irrigated is about 40% that under the common planting condition, and the output is more than 150% that under the common planting condition; in addition, the peach quality is far more than that of common peach; the market price is the peach is more than 5 time that of the common peach.
Owner:KUNMING JINWOTU ECOLOGY CULTIVATION

Polar inertial navigation method based on horizontal wandering coordinate system

ActiveCN104215242ASolve non-applicable problemsSatisfy sailing requirementsNavigation by speed/acceleration measurementsLow latitudeGeographic coordinate system
The invention discloses a polar inertial navigation method based on a horizontal wandering coordinate system. The method includes the steps: building a horizontal earth ellipsoid coordinate system, a horizontal geographic coordinate system and the horizontal wandering coordinate system, setting a traditional geographic coordinate system of initial navigation time as an initial horizontal wandering coordinate system and performing mechanical layout by taking the horizontal wandering coordinate system as a navigation coordinate system of a strap-down inertial navigation system; solving the problem of strap-down algorithm failure based on the geographic coordinate system due to meridian convergence in polar regions based on the inertial navigation layout mode of the horizontal wandering coordinate system. Besides, mechanical layout is performed in wandering azimuth at low latitudes, the internal integrity of a global navigation resolving algorithm is ensured by combining the modes, switching logic design of different latitudes and the transformational relationship between parameters of different navigation coordinate systems are avoided in the strap-down inertial navigation system, and complicated physical platform switching is avoided in a platform inertial navigation system.
Owner:SOUTHEAST UNIV

Low-quality face comparison method based on deep convolution neural network

The invention discloses a low-quality face comparison method based on a deep convolution neural network. The method comprises the following steps: each image in a face training database is sent to a constructed deep convolution neural network for feature extraction; the extracted features are inputted to a fully-connected layer and are projected to a projection matrix in low-latitude space throughaffine; feature vectors obtained and calculated by the projection matrix are trained through a two-norm normalized spherical loss function; through a gradient descent method, the weight value of eachfilter in the fully-connected layer and the deep convolution neural network is found out, and the deep convolution neural network with a comparison passing rate to be the highest is selected; and thefeature vector of a to-be-detected face image and the feature vector of each fact answer image in a low-quality face test database are subjected to cosine distance calculation, and the same person isjudged if the cosine value is smaller than a threshold. The method is used for high-efficiency comparison on a low-quality face, fewer calculation resources are used, and both the face comparison precision and the comparison speed can be considered at the same time.
Owner:上海敏识网络科技有限公司

Weighted average temperature calculation method applicable to low latitude regions in China

ActiveCN107180128AIn line with the law of changeEliminate systematic biasDesign optimisation/simulationSpecial data processing applicationsGround temperatureLow latitude
The present invention discloses a weighted average temperature calculation method applicable to the low latitude regions in China. The method comprises the following steps: S1: constructing a weighted average temperature ITm model applicable to the low latitude regions in China; S2: calculating the approximate true value Tm of the weighted average temperature at the observation station by using the adiosonde data at the observation station; S3: using the approximate true value Tm of the weighted average temperature obtained in the step S2 to determine values of the coefficients a0, a1, a2 and a3 of the ITm model by using the least squares method; and S4: according to the established ITm model, calculating the weighted average temperature ITm by using the ground temperature Ts of the observation station, the observation station latitude phi, and the observation station elevation h. According to the method provided by the present invention, the correction items of the latitude and the elevation are added based on the Bevis model, the change regulation of weighted average temperature is more in line with, systematic deviation of the Bevis model in China is eliminated, accuracy for calculating the weighted average temperature in the low latitude regions in China by using the method provided by the present invention is better than the accuracy by using the Bevis model.
Owner:SOUTHEAST UNIV

Four-crop-a-year cultivation method for low-latitude high-elevation area dry land

The invention discloses a four-crop-a-year cultivation method for a low-latitude high-elevation area dry land. The method is characterized in that the first crop is potato, the second crop is vegetable, the third crop is corn, and the four crop is cereal or vegetable; the potato is sown from the last ten days of December of last year to the middle ten days of January of the following year; the second-crop vegetable is sown when the third-crop corn is transplanted between corn lines; the third-crop corn is transplanted after the first-crop potato is harvested; and the four-crop cereal or vegetable is sown after the second-crop vegetable is harvested. According to the four-crop-a-year cultivation method for the low-latitude high-elevation area dry land, which is disclosed by the invention, the staggering and the collocation of different crops in time and space are fully considered, a proper cultivation mode is adopted to realize the four-crop-a-year cultivation method with high yield and high efficiency, good harvest is obtained, the multiple cropping index is improved, and the income of each acre is above 5300yuan. Compared with the traditional planting mode in the area, the economic income is improved by 41.6-66.87%, and a new cultivation technical mode is provided for the poverty alleviation and economic development of farmers in the area.
Owner:INST OF QUALITY STANDARD & DETECTION TECH YUNNAN ACAD OF AGRI SCI

Grid curved surface reconstruction method for scene understanding

The invention discloses a grid curved surface reconstruction method for scene understanding, and belongs to the field of three-dimensional graphics. The method comprises the following steps of: automatically identifying abnormal data through a mathematical model based on an undirected graph network, and estimating and adjusting a point cloud normal vector in an internal curved surface mapping manner; solving low-latitude feature information of the point cloud model, extracting a skeleton center curve, and designing a block segmentation mode of a complex branch area; for the point cloud from which the branches are removed, adopting a depth map mapping mode to identify and construct a visual field visible area of the point cloud, and designing a visual clustering-based slice body segmentation mode; constructing a self-learning scene understanding model based on the segmentation result, and realizing automatic restoration of the missing region; finally, designing a point cloud reconstruction algorithm based on a hyperspherical mapping mechanism, and surface data reconstruction loyalty of the original point cloud is achieved, and the method can be applied to efficient and accurate reconstruction of a CAD model, a building, an organism and a point cloud model mixed with multiple scenes.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS +1

Method for culturing seedlings of Portunus tritubereulatus in north and breeding Portunus tritubereulatus in south

The invention relates to a method for culturing seedlings of Portunus tritubereulatus in the north and breeding the Portunus tritubereulatus in the south, which comprises the following steps: obtaining brood Portunus tritubereulatus from a natural sea area in the north of the Taiwan Strait or a Portunus tritubereulatus culture pond from August to mid-October, then performing artificial breeding on the brood Portunus tritubereulatus or breeding the brood Portunus tritubereulatus in an earthen pond in the north to obtain juvenile Portunus tritubereulatus; and conveying the juvenile Portunus tritubereulatus serving as the seedlings of the Portunus tritubereulatus to the sea area at a low latitude in the south of the Taiwan Strait, and performing out-of-season breeding on the Portunus tritubereulatus. The Portunus tritubereulatus which is bred in the north can be bred in the south, so that the Portunus tritubereulatus appears on the market in the seasons when the Portunus tritubereulatus cannot be bred in the north from December to next March, and the out-of-season breading of the Portunus tritubereulatus is carried out by using the advantages that the temperature in the south at the low latitude is higher and the brood Portunus tritubereulatus exists in the northern autumn.
Owner:GUANGDONG OCEAN UNIVERSITY

Method for calculating geomagnetically induced current of grid in middle-low latitude region

The invention discloses a method for calculating geomagnetically induced current (GIC) of a grid in a middle-low latitude region. According to the method, on the basis of a global three-dimensional magnetosphere numerical model (a PPMLR-MHD (Lagrangian version of Piecewise Parabolic Method-Magnetohydrodynamic) model), solar wind parameters observed by a satellite serve as input conditions, geomagnetic disturbance generated by current is calculated by performing integration on a magnetic layer and an ionized layer current system, the geomagnetically induced current in the ground grid is calculated, the problem that the transitional predicting method is not suitable for calculating the GIC in the middle-low latitude region is solved, and the GIC of the grid in the middle-low latitude region calculated by the method can reflect the basic characteristic of the induced current which is actually monitored and is calculated by geomagnetic disturbance. By the method, people can timely calculate the GIC of the grid in the middle-low latitude region according to the solar wind parameters observed by an upstream satellite, whether the grid is invaded by a disastrous space weather event or not is estimated, and an active prevention measure is taken to prevent serious economic and social loss.
Owner:NAT SPACE SCI CENT CAS

Mid-and-low-latitude region target non-along-track strip dividing and observing method

The invention aims to solve the technical problem of providing an angle stepping rotary dividing method for carrying out non-along-track strip division on a region target so as to solve the problem of high cost of observing the region target in an initiative push-scanning imaging manner. The invention adopts the technical scheme that initial information is acquired; visibility calculation is carried out on an observed target; a datum division scheme is determined; and the angle stepping rotary dividing method is adopted to carry out screening of division schemes and feasibility verifying. The angle stepping rotary dividing method has the beneficial effects that by adopting the non-along-track strip dividing method, a division direction is optimized, and the number of strips for dividing the same region target is reduced, so that observing time is reduced; by adopting a strip overlapping ratio, an offset error caused by on-orbit satellite attitude control can be avoided; optimization is carried out by adopting an observing sequence next to reciprocating push-scanning, so that attitude maneuver time and an attitude maneuver amplitude among strips are reduced; optimization of the observing time reduces an attitude maneuver amplitude of the push-scanning process; feasibility testing on the observing scheme ensures feasibility of the observing scheme.
Owner:NAT UNIV OF DEFENSE TECH

Clustering-based low-earth-orbit satellite failure discovery method

InactiveCN103701548AIncrease flexibilitySolve the problem of relying on ground station measurement and controlRadio transmissionRelay systems monitoringLow latitudeNetwork architecture
The invention discloses a clustering-based low-earth-orbit satellite failure discovery method. The clustering-based low-earth-orbit satellite failure discovery method comprises the following steps: by adopting a double-layer satellite network architecture of a geostationary-earth-orbit (GEO) satellite/ a low-earth-orbit (LEO) satellite, by virtue of a clustering concept, and with an axis penetrating through the south and north poles as a boundary, dividing a circular LEO satellite orbit into two LEO satellite clusters in the east and west hemispheres; in each cluster, selecting the LEO satellite with the lowest latitude as a cluster head of the cluster for collecting failure information of the LEO satellites in the cluster, sending the collected failure information to the GEO satellite covering the LEO satellites, and uniformly mastering the failure information of the LEO satellites by the GEO satellite with strong on-board processing capability. By the clustering-based low-earth-orbit satellite failure discovery method, LEO satellite failure discovery breaks away from a traditional ground station measurement and control technology with strong geographical dependence, so that failure discovery flexibility of the LEO satellite is greatly improved.
Owner:NANJING UNIV OF POSTS & TELECOMM

Short-term forecast method of ionospheric scintillation in middle and low latitudes

The invention discloses a short-term prediction method for ionospheric scintillation in middle and low latitude regions, comprising: obtaining the average value of the ionospheric scintillation index after filtering and averaging the measured scintillation indices; The strength and phase of the signal, analyze the ionospheric heterogeneous body characteristic parameters, obtain the current moment ionospheric heterogeneous body distribution state according to the ionospheric heterogeneous body characteristic parameters; according to the current moment ionospheric heterogeneous body distribution state, Using the analyzed characteristic parameters of ionospheric heterogeneity, the distribution of ionospheric heterogeneity in the future time is obtained; according to the distribution status of ionospheric heterogeneity in the future and user information, the ionospheric scintillation on a given link is obtained Intensity; the present invention provides short-term scintillation forecasting services for various spatial information systems in the middle and low latitudes of my country, and can know the impact of ionospheric scintillation that user systems may encounter in real time or in advance according to system parameters and specific use environments.
Owner:THE 22ND RES INST OF CHINA ELECTRONICS TECH GROUP CORP

Structure variable mixed-orbit satellite constellation

ActiveCN106788671AIncreased global coverage multiplicityImprove self-management abilityNetwork topologiesRadio transmissionNatural satelliteLow latitude
The invention discloses a structure variable mixed-orbit satellite constellation, comprising a GEO (Geosynchronous Orbit) sub constellation, an IGSO (Inclined Geo Stationary Earth Orbit) sub constellation and an MEO (Medium Earth Orbit) sub constellation. The GEO sub constellation comprises n GEO satellites distributed on n orbit positions of a geosynchronous orbit, and coverage areas between the adjacent satellites are connected and cover medium and low latitude areas in a full longitude manner. The IGSO sub constellation comprises five IGSO satellites, wherein the IGSO1, IGSO2 and IGSO3 satellites are located in the same orbit plane, and the phase difference between the adjacent satellites is 120 degrees; and simultaneously, the IGSO3, IGSO4 and IGSO5 satellites have the same ground track. The MEO sub constellation comprises m*k satellites distributed on k orbit planes, m satellites are on each orbit plane, and the MEO sub constellation has global coverage capability. When the structure of the constellation is reconstructed, the IGSO4 and IGSO5 satellites flexibly enter an HEO (High-altitude Earth Orbit) and run. The constellation has excellent global coverage capability, self management capability and flexible and variable structure.
Owner:CHINA ACADEMY OF SPACE TECHNOLOGY

Two-station direction-finding cross positioning tracing algorithm on earth surface based on rhumb lines

The invention designs an algorithm flow for carrying out cross positioning tracing by using rhumb lines of two observation stations on the earth surface. The invention provides a method for positioning and tracing a plurality of moving targets through crossing the rhumb lines by using two passive direction-finding sensors in a region which is at low latitude on the earth surface, so as to solve the problems of the traditional method that the adaptable region range is small, the positioning and tracing precision is low and the calculation amount is too great. The algorithm is characterized in that (1) in the algorithm principle, longitude and latitude coordinates of the two observation stations are positioned and the positions of a target relative to the two stations are respectively obtained by direction finding, so as to determine the rhumb lines which pass through each observation station from the measured azimuth angles; if the same target is observed, the two rhumb lines are crossed at one point and an approximate target position is obtained by revising a crossed point coordinate; (2) an algorithm formula derivation process is provided; and (3) the algorithm flow of intensive type cross positioning tracing and the algorithm flow of distribution type cross positioning tracing are provided based on the algorithm principle and the formula. The method disclosed by the invention is applicable to rapidly and accurately positioning and tracing of a plurality of moving targets, and has important applications values on aspects of military use and civil use.
Owner:NAVAL AERONAUTICAL & ASTRONAUTICAL UNIV PLA

Global map data storage and organization method and calling method

The invention provides a global map data storage and organization method and a calling method. The global map data storage and organization method includes the steps of projecting a global map to a global coordinate frame, establishing a global geographic grid frame according to the global coordinate frame, slicing the global map to obtain tile data corresponding to the global map, and packaging and storing the tile data according to the geographic grid frame. The calling method includes the steps of receiving a map displaying request carrying longitude and latitude coordinates and displayinggrades, determining tile packets corresponding to the longitude and latitude coordinates according to the longitude and latitude coordinates and the displaying grades, and obtaining the tile data corresponding to the longitude and latitude coordinates from the tile packets. The complete global map is established by means of the Mercator projection in low-latitude areas and the ortho-axis azimuth projection in high-longitude areas; when the packaged and stored tiles are called, the target tile packets are retrieved from a relatively small number of tile packets, then the target tile data is retrieved from the target tile packets, the time consumed for retrieval is short, and the calling speed and efficiency of mass tiles are improved.
Owner:北京星球时空科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products