4results about How to "Reduce observation" patented technology

The application relates to a sequence feature space-time construction method of autonomous optical navigation, and belongs to the technical field of spacecraft navigation, guidance and control. System state equations of visual aided inertial navigation in an unknown environment are established. Image features corresponding to unknown land marks which have the largest contribution to navigation accuracy in a field of view are selected in space. Land marks are observed, and observation information is taken as input of a Kalman filter to obtain optimal estimation of each state variable. The optimal estimation of each state variable is taken as a navigation parameter to perform landing navigation of a lander. A next observation time is calculated. Land marks are re-observed to obtain optimal estimation of each state variable. The optimal estimation of each state variable is taken as a navigation parameter at the time to perform landing navigation of the lander. The application obtains an optimal observation interval between two observations by solving an observation interval time which makes a proposed depth error model minimum, can effectively reduce unnecessary observation, and greatly reduces a calculation burden caused by image processing.

The utility model discloses a high-precision dynamic flow balance valve, which relates to the technical field of balance valves and comprises an electric actuator, a balance valve component is arranged below the electric actuator, and two flow pressure monitoring meters are arranged on the front surface and the rear surface of the top of the balance valve component. The front portion and the rear portion of the balance valve assembly are in threaded connection with two external assemblies. According to the high-precision dynamic flow balance valve, the threaded plastic inner layer fixedly connected to the outer surface of the mounting opening achieves the effect that a connecting water pipe is not rusted after being used for a long time, and later mounting and dismounting are affected, meanwhile, a mounting groove ring formed in the inner wall of an externally-connected threaded block is used for assisting mounting of a damper and a second spring, and the service life of the damper and the second spring is prolonged. The external threaded block is connected with an external water pipe through the threaded plastic inner layer, applies pressure to the rubber ring and transmits the pressure to the first springs and the hard rubber ring, and the damper and the second spring are used for achieving the effects of extruding and buffering the pressure and improving the sealing effect.

The application provides a water quality comprehensive evaluation method based on random forest optimization of water quality indexes, comprising the following steps: determining a river section and water quality indexes, obtaining a measured data set, and calculating a water quality index data set; dividing the water quality index data set into a training set and a prediction set; constructing a training model based on the training set; constructing a prediction model based on the prediction set, predicting the water quality index, and evaluating the performance of the training model; based on the training result and the evaluation result, determining the optimized water quality indexes according to the contribution degree ranking; calculating the water quality index data set based on the optimized water quality indexes; gradually reducing the number of optimized water quality indexes, and calculating the water quality index data set; evaluating the prediction results of different numbers of optimized water quality indexes one by one, and determining the optimal water quality indexes; and calculating the water quality index of the river by using the optimal water quality indexes, so as to realize the water quality comprehensive evaluation. The method takes into account the accuracy and economy of water quality evaluation, reduces the observation of non-key indexes as much as possible, and reduces the evaluation cost.

The utility model relates to the technical field of monitoring devices, and discloses a roadbed settlement monitoring device which comprises two measuring rods, the two measuring rods are distributed up and down, the interiors of the two measuring rods are of hollow structures, a plurality of sliding blocks are fixedly installed on the surfaces of the two measuring rods, and a plurality of through grooves are formed in the surfaces of the two measuring rods. According to the monitoring device provided by the utility model, through the guide cooperation of the slide block and the L-shaped groove and the automatic locking structure of the clamping block and the first spring, the rapid splicing and dismounting between the upper and lower measuring rods are realized, the dismounting convenience of the device is improved, the locking can be realized only by aligning the slide block and the L-shaped groove and pressing and rotating the slide block and the L-shaped groove during splicing, the whole measuring rod does not need to be rotated, the field operation intensity is reduced, and the working efficiency is improved. The device can flexibly meet the increasing and decreasing requirements of measuring rod sections with different embedding depths, locking of the clamping block on the sliding block can be relieved only by pulling down the moving ring during disassembly, the problem of thread corrosion clamping stagnation does not need to be solved, the repeated utilization rate of the device is increased, and the field construction efficiency of roadbed settlement monitoring is remarkably improved.