CN103218523A - Method for visualizing airport noise based on grid queues and piecewise fitting - Google Patents

Abstract

The invention discloses a method for visualizing airport noise based on grid queues and piecewise fitting and belongs to the field of airport noise isoline drawing. The method comprises the following steps of first establishing an initial isoline array according to the isoline drawing requirements of the airport noise, establishing an isoline grid queue array Hi which is dynamically drawn about current noise, and then processing real-time noise data by a curve piecewise fitting prediction algorithm to obtain a data set Si meeting dynamic drawing requirements; processing the Hi and the Si by a grid queue equivalent point swing algorithm to obtain an isoline grid queue array Hi+1 at the next moment; processing the Hi+1 by a grid cell isoline tracking algorithm to obtain a real-time isogram; and finally repeating steps 2 to 5 to dynamically draw the noise isogram. The method prevents grids from being traversed for multiple times and can reflect the dynamic variation of isolines and meet real-time requirements.

Description

Airport noise method for visualizing based on grid queues and piecewise fitting

Technical field

The present invention relates to a kind of airport noise method for visualizing, relate in particular to a kind of airport noise isoline dynamic drafting method, belong to airport noise isoplethes drawing field.

Background technology

Along with the quick growth of aviation services amount, has accelerated the enlarging of organic field and building of new airport in domestic most of cities.Because factor affecting such as the addressing of irrational airport, flight arrangements, the airport more and more receives publicity to the aircraft noise influence of peripheral community, and the airport noise problem becomes increasingly conspicuous.

Airport noise isogram (noise contours) is to describe, analyze, estimate the main data that the following institute in around the airport and the navigation channel regional environmental noise of passing through influences, and is the scientific basis that definite airport addressing and surrounding ground thereof are made rational planning for.Airport noise isoplethes drawing method has all multi-methods in Surfer, INM, the Noisemap software at present, also just like the method for introducing in Chinese invention patent ZL200510066109.6, the Chinese invention patent application 201110260312.2.Said method is based on traditional gridding method and improves, and raises the efficiency by the search strategy of change equivalent point and the tracing step of isoline.Because aircraft noise has the temporal and spatial characteristic, and traditional neighbourhood noise isogram is embodied on the per day noise level mostly, the isoplethes drawing method mainly concentrates in the performance of static data at present, require generally to have following problem than higher field in real-time: 1, the Static Equivalent line is drawn the influence that average noise can only be provided, and can not check real-time noise profile situation; 2, draw the progressive formation that can not reflect isogram based on the essence of acquisition noise data; 3, the computational data amount of noise is big in the dynamic drafting, and conventional isoplethes drawing algorithm need carry out repeatability analysis to each data set, has increased computation complexity; 4, Chang Gui dynamic drafting is a moment numerical value in the middle of obtaining by linear interpolation, can produce when the research aircraft noise changes immediately than mistake; 5, Chang Gui isoplethes drawing adopts identical processing mode when drawing the multiframe data, and the former frame data can not offer back one frame and draw use.

Summary of the invention

The objective of the invention is to: propose a kind of airport noise isoline dynamic drafting method, to reduce computation complexity and requirement of real time based on grid queues and piecewise fitting.

This method comprises the steps:

Step 1: set up initial noise contours array according to the rendering request of airport noise isoline;

Step 2: the current noise contours grid queues array H that makes up dynamic drafting _i, subscript i is the element numbering in the initial noise contours array;

Step 3: utilize curve segmentation match prediction algorithm that the real-time noise data are handled, be met the data set S of dynamic drafting requirement _i

Step 4: utilize the grid queues equivalent point to wave algorithm to H _i, S _iHandle, obtain next noise contours grid queues array H constantly _I+1

Step 5: utilize the interior contour tracing algorithm of grid to H _I+1Handle, obtain real-time noise contours figure;

Step 6: circulation execution in step 2 is to step 5, and dynamic drafting goes out noise contours figure.

Further, the particular content of described step 2 is:

If 1. the zero hour, then travel through all grids, find out the grid of noise contours process, preserve the grid numbering with the form of formation respectively for every noise contours, make up H ₀

2. if previous moment has been set up H _I-1, then make H _i=H _I-1

Technique effect:

1, improved precision of prediction by the real-time noise value in the introducing sectional curve match prediction flight course incident, and by integrated study thought.

2, the isoline grid queues method by waving based on equivalent point, having overcome needs the constantly drawback of traversal in traditional contour tracing algorithm, can reduce the grid node number that need recomputate noise figure simultaneously, has reduced computation complexity.

3, on Data Source, obtain the conventional isoplethes drawing method of instant data set compared to need, added prediction to data, alleviated high dependency to data.

4, based on isoline grid queues method, real-time by the dynamic change of the relation of the gradual change between formation reflection isoline, and result of calculation farthest is applied.

Description of drawings

Fig. 1 is a curve segmentation match prediction algorithm process flow diagram.

Fig. 2 waves algorithm flow chart for the grid queues equivalent point.

Fig. 3 is a contour tracing algorithm flow chart in the grid.

Embodiment

Below the invention will be further described.

The present invention is a kind of airport noise isoline dynamic drafting method based on grid queues and piecewise fitting, and the key step of this method is as follows:

Step 1: set up initial noise contours array C according to the rendering request of airport noise isoline.

With the single flight noise data in certain airport is sample instance, and the rendering request of noise contours is: isoline minimum value 50dB, and isoline maximal value 100dB, isoline spacing 5dB, therefore the initial noise contours array of setting up is C[50,55 ..., 100].

Step 2: the current noise contours grid queues array H that makes up dynamic drafting _i, subscript i is the element numbering among the initial noise contours array C.

If 1. the zero hour, then travel through all grids, utilize conventional contour tracing algorithm to find out the grid of noise contours process, preserve the grid numbering with the form of formation respectively for every noise contours, make up H ₀Particular content is: traversal C.For isoline is C _i, make up grid queues q _{0, i}, travel through all grids, if there is equivalent point in certain grid limit,, and the numbering of two grids under the new equivalent point added q then along the position that the row or column at this place, grid limit is calculated new equivalent point _{0, i}, revise corresponding grid sign, with q _{0, i}Add H ₀

2. if previous moment has been set up H _I-1, the promptly current H that exists _I-1, then indirect assignment is given H _iEven, H _i=H _I-1

Step 3: utilize curve segmentation match prediction (RTP-CPFC) algorithm that the real-time noise data are handled, be met the data set S of dynamic drafting requirement _i

The RTP-CPFC algorithm is to carry out the modeling of basic mathematic model according to single monitoring point noise figure change curve piecewise fitting, utilize the unknown noise figure constantly of existing mathematical model prediction then, and determine final forecast model by result with the comparison of acquisition noise value, be used for predicting next noise figure constantly.Because the model in the process revises automatically and model parameter is revised automatically, kept accuracy than higher so predict the outcome.

The flow process of RTP-CPFC algorithm as shown in Figure 1, key step is as follows:

Step 3.1: algorithm initialization, the noise prediction precision threshold T according to appointment, set up the precision of prediction criterion:

$\left\{\begin{array}{c}|f\left(t\right)-y\left(t\right)|\≤T\\ f\left(t\right)\%k=y\left(t\right)\%k\end{array}\right.$

In the formula: f (t) is a t predicted value constantly, and y (t) is a t measured value constantly, and k is the isoline spacing.

Step 3.2: select polynomial function, exponential function as the basic forecast model, select polynomial function below 4 times, exponential function usually as the base curve fitting function.

Step 3.3: certain the some P in the net region, utilize above-mentioned basic model to carry out match respectively, and select optimum model as final mask F according to fitting result and precision of prediction criterion, revise the Prediction Parameters of model correspondence simultaneously.

Step 3.4: for moment t, if the current model that does not meet the demands then predict with current acquisition noise value, otherwise utilize model F to predict, thereby calculate t predicted value constantly.

Step 3.5: repeating step 3.3～3.4 is met the data set S of dynamic drafting requirement _i

Step 4: utilize the grid queues equivalent point to wave (DCC-GQ) algorithm to H _i, S _iHandle, obtain next noise contours grid queues array H constantly _I+1

The DCC-GQ algorithm is to calculate the current time isoline according to the distribution situation of previous moment isoline to distribute, because the position of the isogram equivalent point of adjacent moment is approaching, has reduced the scope and the number of times of search, has improved the efficient of dynamic drafting greatly.

The flow process of DCC-GQ algorithm as shown in Figure 2, key step is as follows:

Step 4.1:, make up isoline grid queues Q based on initial noise contours array C _I+1, traversal C.For isoline is C _i, make up grid queues q _{I+1, i}, traversal Q _iMiddle q _{I, i}Grid, if there is equivalent point in certain grid limit,, and the numbering of two grids under the new equivalent point added q then along the position that this place, grid limit row or column is calculated new equivalent point _{I+1, i}, revise corresponding grid sign, with q _{I+1, i}Add Q _I+1

Step 4.2: traversal Q _I+1Middle q _{I+1, i}Grid, if there is not equivalent point in certain grid limit, then recomputates and judge according to the grid point value, if there is equivalent point, then the numbering with two grids under this grid limit adds q _{I+1, i}, and revise corresponding grid sign, with q _{I+1, i}Add Q _I+1

Step 4.3: obtain final isoline grid queues Q according to above-mentioned two steps _I+1

Step 4.4: repeating step 4.1～4.3 obtains next noise contours grid queues array H constantly _I+1

Step 5: utilize interior contour tracing (CCIG) algorithm of grid to H _I+1Handle, obtain real-time noise contours figure.

The CCIG algorithm is the crossing situation according to isoline and grid limit, judges the trend of isoline in single grid, and has set corresponding contour tracing method respectively according to the difference of number of hits.

The flow process of CCIG algorithm as shown in Figure 3, key step is as follows:

Step 5.1: for grid G, judge the noise figure and the isoline value size on its four summits, there is the number K of equivalent point in the computing grid limit, and the standard of judgement is: if two endpoint values on grid limit are with C _iBe clipped in the middle, then to have property value be equivalent point on this grid limit.

Step 5.2: when K=2, illustrate that there are two equivalent points in this grid, directly connection gets final product; When K=4, utilize the value p of simple average method computing grid central point, and with p and C _iRelatively, if p〉C _i, then connect this both intra-mesh vertex value greater than C _iTwo adjacent equivalent points, otherwise connect the both intra-mesh vertex value less than C _iTwo adjacent equivalent points.

Step 5.3: repeating step 5.1～5.2 obtains real-time noise contours figure.

Step 6: circulation execution in step 2 is to step 5, and dynamic drafting goes out noise contours figure.

Claims (2)

1. the airport noise method for visualizing based on grid queues and piecewise fitting is characterized in that comprising the steps:

Step 1: set up initial noise contours array according to the rendering request of airport noise isoline;

Step 2: the current noise contours grid queues array H that makes up dynamic drafting _i, subscript i is the element numbering in the initial noise contours array;

Step 3: utilize curve segmentation match prediction algorithm that the real-time noise data are handled, be met the data set S of dynamic drafting requirement _i

Step 4: utilize the grid queues equivalent point to wave algorithm to H _i, S _iHandle, obtain next noise contours grid queues array H constantly _I+1

Step 5: utilize the interior contour tracing algorithm of grid to H _I+1Handle, obtain real-time noise contours figure;

Step 6: circulation execution in step 2 is to step 5, and dynamic drafting goes out noise contours figure.

2. the airport noise method for visualizing based on grid queues and piecewise fitting according to claim 1, it is characterized in that: the particular content of described step 2 is:

If 1. the zero hour, then travel through all grids, find out the grid of noise contours process, preserve the grid numbering with the form of formation respectively for every noise contours, make up H ₀

2. if previous moment has been set up H _I-1, then make H _i=H _I-1

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