67results about How to "Practical engineering application value" patented technology

The invention relates to a real-time monitoring method for a road section state of a high road. The method comprises the following steps of: arranging traffic flow detecting points on the high road to be detected, and spacing the detecting points by 800m, wherein each detecting point covers 400m of upstream road sections and 400m of downstream road sections; acquiring historical traffic flow dataand accident data; extracting dangerous traffic flow operation states by using clustering analysis and regression analysis; and giving a method for monitoring and identifying the traffic flow operation states by using a decision tree approach. The method is easy to process and operate and is favorable for real-time identification of high road accident 'black spots'. The real-time monitoring method has practical engineering utilization value of monitoring accident dangerous road sections of the high road in real time.

The invention discloses a method for identifying the ultrasonic guided wave of an oblique crack pipeline through utilizing an improved Duffing chaotic system. The method comprises the following steps: 1, exciting an ultrasonic guided wave signal on the end surface at one side of the pipeline, and allowing the ultrasonic guided wave to traverse all the positions of the pipeline; 2, receiving an ultrasonic guided wave echo signal at the receiving end near the above exciting end, and recording the time history curve of the ultrasonic guided wave propagating in the pipeline, wherein the ultrasonic guided wave echo signal includes an end surface echo signal, a noise signal and an oblique crack defect signal falling into the noise; and 3, detecting and analyzing the ultrasonic guided wave echo signal by utilizing the improved Duffing chaotic system, and extracting and identifying oblique crack defect information falling into the noise to obtain the oblique crack defect condition of the whole pipeline. The method has the advantages of accurate identification of the oblique crack defect in the pipeline, defect detection efficiency increase, maintenance cost reduction, effective prolongation of the ultrasonic guided wave detection range, increase of the detection sensitivity of the slightly-oblique crack defect, and practical engineering application value.

The invention provides a magnetically suspended control moment gyroscope frame system high-precision angular rate control method based on parameter optimization of an extended state observer. Firstly,a voltage and torque output equation of a magnetically suspended control moment gyroscope frame system is built, a state space expression is built on the basis of the equation and converted into an integral series form to design the extended state observer, and finally lumped interference is eliminated through state feedback. By analyzing estimation errors in the observer, a cost function for estimating the influence degree of the system lumped interference and measurement noise is built to minimize the comprehensive influence of the system lumped interference and the measurement noise, and then an adaptive dynamic parameter optimization method is designed. According to the high-precision angular rate control method, a dynamic parameter optimization method for the extended state observeris proposed, dynamic interference suppression and noise resistance performances of the frame system are improved, and the method can be used for achieving high-precision angular rate control of the magnetically suspended control moment gyroscope frame system.

The invention discloses a plane intersection design variable weight comprehensive evaluation method based on a rank sum ratio method. The plane intersection design variable weight comprehensive evaluation method comprises constructing an original data list, editing ranks, applying weights to different evaluation indexes, computing weighting rank sum ratios (RSRs), determining the distribution of the RSRs, computing a regression equation, classifying and sequencing files and other steps. According to the plane intersection design variable weight comprehensive evaluation method, on the basis of designing relevant evaluation indexes for urban road plane intersections under the condition of mixed traffic, variable weight factors and the rank sum ratio method are combined and used for comprehensive evaluation and sequencing of the running conditions of the multiple plane intersections. Besides, an efficiency index and a safety index are combined so that the defect of a traditional single evaluation method with efficiency as priority or safety as priority can be overcome, and meanwhile, the situation that a weight coefficient changes along with the change of an index value is considered so that the defect that a constant weight coefficient is used for the evaluation of multiple targets traditionally is overcome. The plane intersection design variable weight comprehensive evaluation method based on the rank sum ratio method has actual engineering application value in the aspects of judging the running conditions of the intersections and analyzing traffic system crucial reasons.

The invention discloses a prediction method of an urban road signalized intersection direct-left conflict number. A plurality of direct-left conflicts and conflict flow of the direct-left conflicts and geometric characteristics of an intersection serve as data base, and an urban road signalized intersection direct-left conflict prediction model is built by aiming at four different traffic operation conditions and utilizing a mechanism generated when a generalized linear model excavates the traffic conflicts. Direct-left conflict frequency in unit time interval is obtained by substituting traffic flow parameters into the model so as to provide evidence for intersection indirect safety evaluation. According to the urban road signalized intersection direct-left conflict number obtaining method based on the direct-left conflict prediction model, traffic conflicts can be predicted by traffic flow which is easy to be collected, the defect and disadvantage that conflict collecting cost is high in present traffic conflict technology are overcome, and the prediction method is more accurate and scientific compared with manual observation conflicts of the prior art and capable of promoting the traffic conflict technology to be applied in engineers.

The invention relates to a discriminant analysis-based high road real-time traffic accident risk forecasting method. The method comprises the following steps of: building a high road accident risk discrimination model for a detection area; substituting real-time traffic flow characteristic parameters into the high road accident risk discrimination model; and judging whether the risk of traffic accident exists or not. According to the method, traffic accidents can be forecasted in real time by using the real-time traffic flow characteristic parameters acquired by high road traffic detection equipment, the method has relatively high forecasting precision, and technical defects and shortages in the prior art for analyzing traffic safety by using aggregated statistics are overcome. The method has practical engineering application value in the aspects of discrimination of the risk of the high road traffic accidents and forecast of the traffic accidents.

The invention relates to a variable speed-limit control method of expressway based on real-time traffic flow and weather information, which can automatically regulate the speed limit values under various traffic flows and weather conditions according to real-time change of the traffic flows and the weather states, and send the speed limit message to a driver by a variable message board, so as to reduce traffic accident risk. The invention is featured by making use of a traffic flow detection device and a weather environment detection device to obtain real-time traffic flow and weather parameters, automatically regulating the speed limit according to various traffic flows and weather states to overcome the defect and shortcoming that the prior road speed limit can only be fixed and unchanged. Therefore, a dynamic speed limit method according to the real-time traffic flow and weather information has an actual engineering application value in the expressway traffic management and control aspect.