31results about How to "Density Requirements Reduced" patented technology

The invention discloses a multi-section water cup, the cup body comprises an upper cup body and a lower cup body, the upper cup body is in threaded connection with the lower cup body, a cup cover is arranged on the upper cup body, the size of an opening in the connecting position of the upper cup body and the cup cover is smaller than that of an opening in the connecting position of the lower cup body and the upper cup body, and a buoyancy push rod is arranged on the inner side wall of the upper cup body, the buoyancy push rod comprises a floating section and a sinking section, the joint of the floating section and the sinking section is rotationally connected with the upper cup body, a clamping protrusion is arranged on the sinking section, and a second clamping groove matched with the clamping protrusion is formed in the inner side wall of the lower cup body; when the floating section floats, the clamping protrusion on the sinking section is clamped into the second clamping groove. According to the multi-section water cup, the structure is simple, the upper cup body and the lower cup body are detachably connected, when the liquid level in the cup is higher than the connecting position of the upper cup body and the lower cup body, connection of the upper cup body and the lower cup body can be automatically locked, and the situation that liquid is scattered due to mistaken opening is avoided.

The invention discloses an automatic calibration method and device of laser radar parameters and a laser radar. The method comprises the steps of (10) setting a first marker with a first marking point in a calibration field, using the laser radar to carry out laser scanning on the calibration field and obtaining scanning data, (20) fitting the scanning data of a position where the first marker is located, and obtaining the fitting space coordinate of the first marking point, and (30) calculating the laser radar parameters by using an error between the fitting space coordinate and the measurement space coordinate of the first marking point, and carrying out the automatic calibration by using the calculated laser radar parameters. According to the method, device and the laser radar, the fully automatic high precision calibration of the laser radar is realized, the density requirement of a laser point is low, the integrity requirement of marker scanning is low, and the automatic precision inspection and evaluation of calibrated laser radar measurement precision can be carried out.

The invention relates to a locating method of a wireless sensor network based on an RSSI (Received Signal Strength Indicator), which belongs to the technical field of wireless sensor networks and comprises the following steps of: respectively measuring the RSSI values of anchor nodes and a blind node to obtain the information on the distance between the blind node and each anchor node; selecting three anchor nodes nearest to the blind node as reference nodes to perform rough locating to obtain the rough locating position of the blind node; establishing a distribution probability model of the blind node to obtain the distribution probability of the blind node in each position of the wireless sensor network; performing locating searching processing by using the rough locating position of the blind node as an initial position and L1 as step length to obtain the first locating position of the blind node; and performing locating searching by using the (N-1)th locating position as an initial position and L(N) as step length to obtain the Nth locating position of the blind node, i.e. the finial position of the blind node. The invention has low requirements for node density, no environmental interference, great improvement on locating accuracy and low locating error reduced to be between 20% and 50%.

The invention discloses an indoor wireless positioning method by utilizing fingerprint technique. The indoor wireless positioning method by utilizing the fingerprint technique largely lowers the requirements for the density of sampling points, enriches distribution information of signal strength, lightens the workload, and keeps high-precision positioning results. The indoor wireless positioning method by utilizing the fingerprint technique comprises an off-line training phase and an on-line training phase. The off-line training phase includes the following steps: firstly, an indoor environment is set up and signal strength data are acquired; secondly, an original fingerprint database with a low sampling rate is constructed; and thirdly, the original fingerprint database is reconstructed through a low-order matrix fill model, the low-order matrix fill model is minrank (X) s.t.A(X) = B. In the on-line training phase, signal strength vectors used for testing and the signal strength vector of each sampling point in the reconstructed fingerprint database are compared and matched, and position coordinates of a present position are estimated by utilizing the point coordinates of the known sampling points to obtain on-line positioning coordinates.

The invention relates to a sequence-based sensor node positioning method and device, comprising the following steps: the sensor node to be positioned collects signal strength indication values ​​of multiple beacon nodes within the communication range; according to the coordinate position and communication range of each beacon node Carry out area division, sort the signal strength in each area to obtain multiple signature sequences; match and calculate multiple detection sequences with the signature sequence table; the sensor node to be located collects the coordinate position of the beacon node outside the range of one hop and the coordinate positions of the quasi-beacon nodes that have been located; draw vertical bisectors between all beacon nodes and all quasi-beacon nodes outside the range of one hop and each beacon node within the range of one hop in order to obtain the final The area to be located; the centroid of the final area to be located is taken as the coordinate position of the sensor node to be located. The invention has good robustness and higher matching precision, and reduces the requirement on the density of beacon nodes.

The invention discloses a method for increasing the density of parallel arrays of carbon nanotubes by means of the Poisson's ratio of an elastic material. First, the parallel array of carbon nanotubes grown on the substrate is transferred to elastic materials, such as polymethyl methacrylate, silicone rubber or polyester, and other elastic materials; then stretch the carbon nanotubes along the direction of extension. The elastic material makes it shrink in the direction perpendicular to the extension of carbon nanotubes, thereby obtaining high-density carbon nanotubes; finally, the parallel array of carbon nanotubes on the film is transferred to the target substrate. The method of the invention is simple and practical, high in efficiency and low in cost, and can produce high-density and high-quality parallel arrays of pure semiconductor carbon nanotubes.