CN103218523B - Based on the airport noise method for visualizing of grid queues and piecewise fitting - Google Patents

Abstract

The invention discloses a kind of airport noise method for visualizing based on grid queues and piecewise fitting, belong to airport noise isoplethes drawing field.The method first sets up initial isoline array according to the rendering request of airport noise isoline, then builds the current noise isoline grid queues array H of dynamic drafting _i, recycling curve segmentation matching prediction algorithm processes real-time noise data, is met the data set S of dynamic drafting requirement _i, utilize grid queues equivalent point to wave algorithm to H _i, S _iprocess, obtain the isoline grid queues array H of subsequent time _i+1, to utilize in grid contour tracing algorithm to H _i+1process, obtain real-time isogram, last circulation step 2 to step 5, dynamic drafting goes out countermeasures on noise standard.Inventive process avoids the repeatedly traversal of grid, and the dynamic change of isoline can be reflected, meet requirement of real-time.

Description

Based on the airport noise method for visualizing of grid queues and piecewise fitting

Technical field

The present invention relates to a kind of airport noise method for visualizing, particularly relate 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, most domestic city accelerates the enlarging of organic field and building of new airport.Due to factor impacts such as irrational airport site choice, flights arrangements, the aircraft noise impact of airport on Peripheral region more and more receives publicity, and airport noise problem becomes increasingly conspicuous.

Airport noise isogram (noisecontours) describes, analyzes, evaluates the main data that around airport and lower of navigation channel affects through regional environmental noise, is the scientific basis determining that airport site choice and surrounding ground thereof are made rational planning for.Current airport noise isoplethes drawing method has all multi-methods in Surfer, INM, Noisemap software, also just like the method introduced in Chinese invention patent ZL200510066109.6, Chinese invention patent application 201110260312.2.Said method improves based on traditional gridding method, raised the efficiency by the change search strategy of equivalent point and the tracing step of isoline.Because aircraft noise has obvious space-time characterisation, and traditional neighbourhood noise isogram is embodied in per day noise level mostly, current isoplethes drawing method mainly concentrates in the performance of static data, generally there is following problem in the field higher at requirement of real-time: 1, the impact that can only provide average noise drawn by Static Equivalent line, can not check real-time noise profile situation; 2, the essence based on acquisition noise data draws the progressive formation that can not reflect isogram; 3, in dynamic drafting, the calculating data volume of noise is large, and conventional isoplethes drawing algorithm needs to carry out repeatability analysis to each data set, adds computation complexity; 4, conventional dynamic drafting obtains intermediate time numerical value by linear interpolation, can produce comparatively big error when research aircraft noise changes immediately; 5, conventional isoplethes drawing adopts identical processing mode when drawing multiframe data, and after former frame data can not be supplied to, a frame is drawn and used.

Summary of the invention

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

The method comprises the steps:

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

Step 2: the current noise isoline grid queues array H building dynamic drafting _i, subscript i is the element number in initial noisc isoline array;

Step 3: utilize curve segmentation matching prediction algorithm to process real-time noise data, be met the data set S of dynamic drafting requirement _i;

Step 4: utilize grid queues equivalent point to wave algorithm to H _i, S _iprocess, obtain the noise contours grid queues array H of subsequent time _i+1;

Step 5: to utilize in grid contour tracing algorithm to H _i+1process, obtain real-time countermeasures on noise standard;

Step 6: circulation performs step 2 to step 5, and dynamic drafting goes out countermeasures on noise standard.

Further, the particular content of described step 2 is:

If 1. start time, then travel through all grids, find out the grid of noise contours process, with the form of queue, grid numbering is preserved respectively for every bar noise contours, builds H ₀;

If the 2. built vertical H of previous moment _i-1, then H is made _i=H _i-1.

Technique effect:

1, by introducing the real-time noise value in subsection curve drafting prediction flight course event, and improve precision of prediction by integrated study thought.

2, the isoline grid queues method by waving based on equivalent point, overcomes in traditional contour tracing algorithm the drawback needing constantly traversal, can reduce the grid node number needing to recalculate noise figure simultaneously, reduce computation complexity.

3, on Data Source, compared to the conventional isoplethes drawing method that need obtain instant data set, add the prediction to data, alleviate the high dependency to data.

4, based on isoline grid queues method, by the dynamic change of the gradual change relation reflection isoline between queue, real-time, and result of calculation can be made farthest to be applied.

Accompanying drawing explanation

Fig. 1 is curve segmentation matching prediction algorithm process flow diagram.

Fig. 2 is that grid queues equivalent point waves algorithm flow chart.

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

Embodiment

The invention will be further described below.

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 the method is as follows:

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

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

Step 2: the current noise isoline grid queues array H building dynamic drafting _i, subscript i is the element number in initial noisc isoline array C.

If 1. start time, then travel through all grids, utilize conventional contour tracing algorithm to find out the grid of noise contours process, with the form of queue, grid numbering is preserved respectively for every bar noise contours, builds H ₀.Particular content is: traversal C.Be C for isoline _i, build grid queues q _{0, i}, travel through all grids, if certain Grid Edge exists equivalent point, then calculate the position of new equivalent point along the row or column at this Grid Edge place, and the numbering of two grids belonging to new equivalent point is added q _{0, i}, the Marking the cell that amendment is corresponding, by q _{0, i}add H ₀.

If the 2. built vertical H of previous moment _i-1, namely current exist H _i-1, then indirect assignment is to H _ieven, H _i=H _i-1.

Step 3: (RTP-CPFC) algorithm processes real-time noise data to utilize curve segmentation matching to predict, is met the data set S of dynamic drafting requirement _i.

RTP-CPFC algorithm is the modeling carrying out basic mathematic model according to single monitoring point noise figure change curve piecewise fitting, then the noise figure in existing mathematical model prediction unknown moment is utilized, and by and the result that compares of acquisition noise value determine final forecast model, be used for predicting the noise figure of subsequent time.Due to the model auto modification in process and model parameter auto modification, maintain higher accuracy so predict the outcome.

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

Step 3.1: algorithm initialization, according to the noise prediction precision threshold T specified, set up 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 formula: the predicted value that f (t) is t, the measured value that y (t) is t, k is isoline spacing.

Step 3.2: select forecast model based on polynomial function, exponential function, selects iunction for curve based on less than 4 times polynomial functions, exponential function usually.

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

Step 3.4: for moment t, the model do not met the demands if current, then predict by current acquisition noise value, otherwise utilize model F to predict, thus calculate the predicted value of t.

Step 3.5: repeat step 3.3 ~ 3.4, be met the data set S of dynamic drafting requirement _i.

Step 4: utilize grid queues equivalent point to wave (DCC-GQ) algorithm to H _i, S _iprocess, obtain the noise contours grid queues array H of subsequent time _i+1.

DCC-GQ algorithm calculates current time distribution of contours according to the distribution situation of previous moment isoline, because the position of the isogram equivalent point of adjacent moment is close, decreases scope and the number of times of search, substantially increase the efficiency of dynamic drafting.

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

Step 4.1: based on initial noisc isoline array C, builds isoline grid queues Q _i+1, traversal C.Be C for isoline _i, build grid queues q _{i+1, i}, traversal Q _imiddle q _i,igrid, if certain Grid Edge exists equivalent point, then calculate the position of new equivalent point along this Grid Edge place row or column, and the numbering of two grids belonging to new equivalent point added q _{i+1, i}, the Marking the cell that amendment is corresponding, by q _{i+1, i}add Q _i+1.

Step 4.2: traversal Q _i+1middle q _{i+1, i}grid, if certain Grid Edge does not exist equivalent point, then recalculate according to Grid point Value and judge, if there is equivalent point, then the numbering of two grids belonging to this Grid Edge being added q _{i+1, i}, and the Marking the cell that amendment is corresponding, by 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: repeat step 4.1 ~ 4.3, obtain the noise contours grid queues array H of subsequent time _i+1.

Step 5: utilize contour tracing in grid (CCIG) algorithm to H _i+1process, obtain real-time countermeasures on noise standard.

CCIG algorithm is according to the crossing situation of isoline with Grid Edge, judges the trend of isoline in single grid, and sets corresponding contour tracing method respectively according to the difference of number of hits.

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

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

Step 5.2: as K=2, illustrates that this grid exists two equivalent points, directly connects; As K=4, utilize the value p of simple average method computing grid central point, and by p and C _irelatively, if p>C _i, then connect this both intra-mesh vertex value and be greater than C _itwo adjacent equivalent points, otherwise connect both intra-mesh vertex value and be less than C _itwo adjacent equivalent points.

Step 5.3: repeat step 5.1 ~ 5.2, obtain real-time countermeasures on noise standard.

Step 6: circulation performs step 2 to step 5, and dynamic drafting goes out countermeasures on noise standard.

Claims (1)

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

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

Step 2: the current noise isoline grid queues array H building dynamic drafting _i, subscript i is the element number in initial noisc isoline array C;

The particular content of step 2 is:

If 1. start time, then travel through all grids, find out the grid of noise contours process, with the form of queue, grid numbering is preserved respectively for every bar noise contours, builds H ₀;

If the 2. built vertical H of previous moment _i-1, then H is made _i=H _i-1;

Step 3: utilize curve segmentation matching prediction algorithm to process real-time noise data, be met the data set S of dynamic drafting requirement _i;

The particular content of step 3 is:

Step 3.1: algorithm initialization, according to the noise prediction precision threshold T specified, set up 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 formula: the predicted value that f (t) is t, the measured value that y (t) is t, k is isoline spacing;

Step 3.2: select forecast model based on polynomial function, exponential function;

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

Step 3.4: for moment t, the model do not met the demands if current, then predict by current acquisition noise value, otherwise utilize model F to predict, thus calculate the predicted value of t;

Step 3.5: repeat step 3.3 ~ 3.4, be met the data set S of dynamic drafting requirement _i;

Step 4: utilize grid queues equivalent point to wave algorithm to H _i, S _iprocess, obtain the noise contours grid queues array H of subsequent time _i+1;

The particular content of step 4 is:

Step 4.1: based on initial noisc isoline array C, builds isoline grid queues Q _i+1, traversal C is C for isoline _i, build grid queues q _{i+1, i}, traversal Q _imiddle q _i,igrid, if certain Grid Edge exists equivalent point, then calculate the position of new equivalent point along this Grid Edge place row or column, and the numbering of two grids belonging to new equivalent point added q _{i+1, i}, the Marking the cell that amendment is corresponding, by q _{i+1, i}add Q _i+1;

Step 4.2: traversal Q _i+1middle q _{i+1, i}grid, if certain Grid Edge does not exist equivalent point, then recalculate according to Grid point Value and judge, if there is equivalent point, then the numbering of two grids belonging to this Grid Edge being added q _{i+1, i}, and the Marking the cell that amendment is corresponding, by 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: repeat step 4.1 ~ 4.3, obtain the noise contours grid queues array H of subsequent time _i+1;

Step 5: to utilize in grid contour tracing algorithm to H _i+1process, obtain real-time countermeasures on noise standard;

The particular content of step 5 is:

Step 5.1: for grid G, judge noise figure and the isoline value size on its four summits, there is the number K of equivalent point in computing grid limit, the standard of judgement is: if two of Grid Edge endpoint values are by C _ibe clipped in the middle, then this Grid Edge exists property value is equivalent point;

Step 5.2: as K=2, illustrates that this grid exists two equivalent points, directly connects; As K=4, utilize the value p of simple average method computing grid central point, and by p and C _irelatively, if p>C _i, then connect this both intra-mesh vertex value and be greater than C _itwo adjacent equivalent points, otherwise connect both intra-mesh vertex value and be less than C _itwo adjacent equivalent points;

Step 5.3: repeat step 5.1 ~ 5.2, obtain real-time countermeasures on noise standard;

Step 6: circulation performs step 2 to step 5, and dynamic drafting goes out countermeasures on noise standard.