CN106297285A - Freeway traffic running status fuzzy synthetic appraisement method based on changeable weight - Google Patents

Abstract

The invention discloses a kind of freeway traffic running status fuzzy synthetic appraisement method based on changeable weight, first according to the vehicle checker data gathered and charge data Calculation Estimation desired value；Then according to dynamic traffic data parameter weight vectors；Set up dynamic-fuzzy-ovcrall evaluation model finally according to weight vectors and calculate the comprehensive evaluation value of freeway traffic running status: freeway traffic running status be evaluated and export evaluation result.The freeway traffic running status fuzzy synthetic appraisement method based on changeable weight that the present invention proposes, based on existing highway data source, utilize dynamic traffic data real-time parameter weight, and use fuzzy synthetic appraisement method that the traffic circulation state of express highway section is evaluated, the method takes four parameters of section saturation, occupation rate, average stroke speed, average travel time delay to be evaluated index for express highway section, realizes fuzzy overall evaluation by changeable weight.

Description

Freeway traffic running status fuzzy synthetic appraisement method based on changeable weight

Technical field

The present invention relates to freeway traffic postitallation evaluation field, a kind of highway based on changeable weight is handed over Logical running status fuzzy synthetic appraisement method.

Background technology

Freeway traffic evaluation of running status system can be that the management and control measure of highway provides reason with migration efficiency Opinion supports.In order to preferably propose freeway management strategy, improve operational efficiency, and at utmost play highway Effect, needs the freeway traffic to different time to run and is evaluated, in order to identify the period that operation conditions is best, and As the reference standard put into practice later with right

At present, fuzzy synthetic appraisement method is the common method in highway postitallation evaluation, and the method is mainly chosen One or more traffic indicators carry out Traffic Evaluation, by qualitative and quantitative assessment highway running status.But evaluate During, the weight of each evaluation index is to be obtained by expert method, is affected very big by subjective factors, and different highways Section, same section different time are due to the dynamic change of traffic data, the index running status reflection to express highway section Significance level may be different.

Therefore, it is necessary to study index weights computational methods based on dynamic traffic data, so that highway is handed over It is more objective, more reasonable that logical running status is evaluated.

Summary of the invention

The purpose of the present invention is to propose to a kind of freeway traffic running status fuzzy overall evaluation based on changeable weight Method；For express highway section running status is reasonably evaluated.

It is an object of the invention to be achieved through the following technical solutions:

The present invention provide freeway traffic running status fuzzy synthetic appraisement method based on changeable weight, including with Lower step:

Step 1: gather highway data and data are carried out pretreatment；Described data include vehicle checker data and charge Data；

Step 2: according to the vehicle checker data gathered and charge data Calculation Estimation desired value；Described evaluation index value includes Calculated flow rate saturation, time occupancy, average travel speed and average travel time are delayed；

Step 3: according to dynamic traffic data, utilize the variance drive principle real-time parameter weight vectors of data；

Step 4: set up dynamic-fuzzy-ovcrall evaluation model according to weight vectors and calculate freeway traffic running status Comprehensive evaluation value:

Step 5: according to comprehensive evaluation value freeway traffic running status be evaluated and export evaluation result.

Further, the data prediction of described step 1 calculates according to following steps:

(11) utilize threshold method that the extraordinary data in vehicle checker data are rejected, specifically comprise the following steps that

Flow threshold q is determined according to below equation:

0≤q≤f_cCT/60；

Wherein: C is road passage capability；T is the time interval of data acquisition；f_cCorrection factor for flow；

Speed v is determined according to below equation:

0≤v≤f_vv₀；

Wherein: v₀Restriction speed for fastlink；f_vCorrection factor for speed.

(12) pretreatment to charge data, specifically comprises the following steps that

Predetermined threshold value TE of journey time is determined according to below equation:

TE=[L/1.5*v₀,24]；

Wherein, TE is effective data intervals；L is road section length；v₀Restriction speed for fastlink；

Judge whether charge data is in predetermined threshold value TE, if it is, charge data is just data, if it does not, Then charge data is extraordinary data；

Reject extraordinary data.

Further, the evaluation index value in described step 2 calculates according to following steps:

Calculating according to below equation of described evaluation index value:

(21) vehicle checker data calculated flow rate saturation and occupation rate are used:

$S=\frac{Q}{C_0};R_t=\frac{1}{T}\underset{i=1}{\overset{n}{\Σ}}{t}_i;$

Wherein: S is link flow saturation；Q is actual vehicle flowrate；C₀Design vehicle flowrate for section；R_tOccupy for the time Rate；T is observation interval；t_iIt is i-th car time of taking detector, i=1,2 ... n；

(22) by the charge ID of expressway tol lcollection data, go out station entrance time and section mileage, obtain each car Distance travelled and journey time, calculate average travel speed and average travel time and be delayed:

$D=\frac{L_D}{T_D}=\frac{\underset{i=1}{\overset{n_D}{\Σ}}{l}_{Di}}{\underset{i=1}{\overset{n_D}{\Σ}}{t}_{Di}};TD=\frac{1}{n}\underset{i=1}{\overset{n}{\Σ}}{\mathrm{td}}_i=\frac{T_{td}}{n}-\frac{l}{v_0};$

Wherein: D is average stroke speed；L_DFor evaluating the total kilometrage of all drivings on period inner evaluation section；T_DFor evaluating The total time of all vehicle drivings in period；n_DFor evaluating all driving vehicle numbers on period inner evaluation section；l_DiDuring for evaluating The mileage of driving vehicle i in section；t_DiRunning time for the vehicle i that drives a vehicle in evaluating the period；TD is that average travel time prolongs By mistake；L is road section length；td_iIt is the journey time of i-th car, T_tdFor total travel time, can be calculated by charge data and obtain； v₀For the speed that passes unimpeded, obtain according to the design speed in section；N is the vehicle number summation passed through in observation time；

Further, the weight vectors in described step 3 calculates according to following steps:

(31) combine sequential weighted average operator TOWA operator and set up the Dynamic Comprehensive Evaluation model of highway:

$y\left(t_k\right)=\underset{j=1}{\overset{m}{\Σ}}{w}_j\left(t_k\right)x_j\left(t_k\right);$

Wherein: y (t_k) it is linear function；w_j(t_k) it is t_k(k=1,2 ... the n) weight in moment；x_j(t_k) it is t_kMoment Index observation；

(32) linear function is calculatedSum of deviation square maximum；

(33) according to below equation structure index matrix A:

Wherein, m represents assessment indicator system index item number, x_i(t_j) represent assessment indicator system index；

(34) calculate w according to below equation and make function y (t_k) sum of deviation square maximum:

$\begin{array}{c}\max \left\{w^{T}Hw\right\}\\ s.t.w^{T}w=1\\ w>0\end{array};$

(35) the Maximum characteristic root characteristic of correspondence vector of H is taken, as weight vectors w.

Further, the dynamic-fuzzy-ovcrall evaluation in described step 4 calculates according to following steps:

(41) set of factors U is set up according to below equation:

U={u₁,u₂,u₃,u₄}={ flow saturation, average stroke speed, occupation rate, journey time is delayed }；

(42) according to below equation foundation evaluation collection V:

V={ is unimpeded, the most unimpeded, typically, crowded, blocking }={ 5,4,3,2,1}；

(43) weight sets W is set up according to below equation:

${w^{\′}}_i=w_i/\underset{i=1}{\overset{4}{\Σ}}{w}_i;$

Wherein, w={w₁,w₂,w₃,w₄, and weight addition

(44) Evaluations matrix R is set up according to below equation:

$R=\left[\begin{array}{c}{r}_1\\ r_2\\ r_3\\ r_4\end{array}\right];$

Wherein, r_jOpinion rating for index；

Multidimensional Evaluations matrix by following for the opinion rating structure of the traffic circulation state in n moment:

$R=\left[\begin{array}{c}{R}_{1j}\\ R_{2j}\\ R_{3j}\\ R_{4j}\end{array}\right]=\left[\begin{array}{cccc}{r}_{11}& r_{12}& \mathrm{...}& r_{1n}\\ r_{21}& r_{22}& \mathrm{...}& r_{2n}\\ r_{31}& r_{32}& \mathrm{...}& r_{3n}\\ r_{41}& r_{42}& \mathrm{...}& r_{4n}\end{array}\right];$

Wherein: R_1j, R_2j, R_3j, R_4jRepresent flow saturation respectively, evaluate travel speed, occupation rate, journey time delay Opinion rating value at moment j；J=1,2 ... n.

(45) carry out fuzzy overall evaluation according to below equation, calculate the product of matrix according to weight vectors and Evaluations matrix Obtain comprehensive evaluation value:

Wherein, bn represents the comprehensive evaluation result value of moment n.

Further, the evaluation result in described step 5 is to try to achieve combining of a certain moment by weight vectors and Evaluations matrix Close evaluation result, determine traffic circulation state by the numerical value of evaluation result.

Owing to have employed technique scheme, present invention have the advantage that:

The freeway traffic running status fuzzy synthetic appraisement method based on changeable weight that the present invention proposes, based on existing There is highway data source, utilize dynamic traffic data real-time parameter weight, and use fuzzy synthetic appraisement method to height The traffic circulation state of speed highway section is evaluated, the method determining road section traffic volume state.The method is for highway road Section is taked section saturation, occupation rate, average stroke speed, average travel time to be delayed four parameters to be evaluated index and build Vertical, realize fuzzy overall evaluation by changeable weight.

Other advantages, target and the feature of the present invention will be illustrated to a certain extent in the following description, and And to a certain extent, will be apparent to those skilled in the art based on to investigating hereafter, or can To be instructed from the practice of the present invention.The target of the present invention and other advantages can be realized by description below and Obtain.

Accompanying drawing explanation

The accompanying drawing of the present invention is described as follows.

Fig. 1 is the flow chart of the present invention.

Fig. 2 is the weight calculation figure of the present invention.

Detailed description of the invention

The invention will be further described with embodiment below in conjunction with the accompanying drawings.

As it can be seen, the traffic circulation state of express highway section is entered by the fuzzy synthetic appraisement method that the present embodiment provides Row is evaluated, and realizes especially by step as described below:

Step 1: data prediction

(1) first with threshold method, extraordinary data are rejected, vehicle checker Data Data pretreatment:

The zone of reasonableness of flow threshold q is:

0≤q≤f_cCT/60

Wherein: C is road passage capability (veh/h)；T is the time interval (min) of data acquisition；f_cCorrection for flow Coefficient, generally takes 1.1-1.3.

The zone of reasonableness of speed v is: 0≤v≤f_vv₀

Wherein: v₀For the restriction speed of fastlink, it is different that different sections limits speed, section itself determine；f_vFor The correction factor of speed, generally takes 1.3-1.5.

The reasonable value scope of occupation rate o: 0≤o≤100%.

(2) charge data pretreatment:

Think that journey time is at interval TE=[L/1.5*v₀, 24] in data be just data, outside this interval Data are considered extraordinary data and reject.

Wherein, TE is effective data intervals；L is road section length；v₀Restriction speed for fastlink.

Step 2: parameter parameter value

Based on the vehicle checker data gathered and charge data Calculation Estimation desired value, concrete formula is as follows:

(1) the 5mim data calculated flow rate saturation of employing vehicle checker, and occupation rate:

$S=\frac{Q}{C_0};R_t=\frac{1}{T}\underset{i=1}{\overset{n}{\Σ}}{t}_i;$

Wherein: S is link flow saturation；Q is the actual vehicle flowrate of 5min；C₀Design vehicle flowrate for section；R_tFor the time Occupation rate；T is observation interval；t_iIt is i-th car time of taking detector, i=1,2 ... n；

(2) by the charge ID of expressway tol lcollection data, go out the station entrance time, the field such as section mileage, obtain every The distance travelled of car and journey time, calculate average travel speed, and average travel time be delayed:

$D=\frac{L_D}{T_D}=\frac{\underset{i=1}{\overset{n_D}{\Σ}}{l}_{Di}}{\underset{i=1}{\overset{n_D}{\Σ}}{t}_{Di}};TD=\frac{1}{n}\underset{i=1}{\overset{n}{\Σ}}{\mathrm{td}}_i=\frac{T_{td}}{n}-\frac{l}{v_0};$

Wherein: D is average stroke speed；L_DFor evaluating the total kilometrage of all drivings on period inner evaluation section；T_DFor evaluating The total time of all vehicle drivings in period；n_DFor evaluating all driving vehicle numbers on period inner evaluation section；l_DiDuring for evaluating The mileage of driving vehicle i in section；t_DiRunning time for the vehicle i that drives a vehicle in evaluating the period.TD is that average travel time prolongs By mistake；L is road section length；td_iIt is the journey time of i-th car, T_tdFor total travel time, can be calculated by charge data and obtain； v₀For the speed that passes unimpeded, can obtain according to the design speed in section；N is the vehicle number summation passed through in observation time.

Step 3: agriculture products weight w

According to dynamic traffic data, utilize the variance drive principle real-time parameter weight of data:

(1) due to weight w_jWith the sequential relationship that time t exists implicit expression, in conjunction with sequential weighted average operator TOWA operator, The Dynamic Comprehensive Evaluation of highway is expressed as:

$y\left(t_k\right)=\underset{j=1}{\overset{m}{\Σ}}{w}_j\left(t_k\right)x_j\left(t_k\right);$

Wherein: y (t_k) it is linear function；w_j(t_k) it is t_k(k=1,2 ... the n) weight in moment；x_j(t_k) it is t_kMoment Index observation；

(2) simultaneously, in order to highlight the difference between system s running status the most in the same time to greatest extent, i.e. to allow linear FunctionSum of deviation square is maximum.

(3) it is assumed that assessment indicator system has m item index, from evaluating moment t_nPush away forward n-1 unit of time to t₁Time Carving, all indexs are represented by x_i(t_j) (i=1,2 ... n；J=1,2...m)

Obtain index matrix A:

W makes function y (t_k) sum of deviation square maximum, then the problem that can be exchanged into linear programming, have a following formula:

$\begin{array}{c}\max \left\{w^{T}Hw\right\}\\ s.t.w^{T}w=1\\ w>0\end{array};$

Then:

Take the Maximum characteristic root characteristic of correspondence vector of H, for weight vectors w.

Step 4: dynamic-fuzzy-ovcrall evaluation realizes

The general step of fuzzy overall evaluation is performed as follows:

(1) set of factors U is set up: set of factors refers to pass judgment on the factor composition of object and gathers, also referred to as parameter index,

U={u₁,u₂,u₃,u₄}={ flow saturation, average stroke speed, occupation rate, journey time is delayed }；

(2) evaluation collection V is set up: pass judgment on the set that the set to the comment of object is comment composition exactly, based on people's readability Property principle and freeway traffic evaluate demand, and the grading standard of highway, evaluate collection

V={ is unimpeded, the most unimpeded, typically, crowded, blocking }={ 5,4,3,2,1}；

(3) weight sets W is set up: according to the weight vectors w={w calculated in step 3₁,w₂,w₃,w₄, weight is added Need to use normalized principle to process, redefine weight sets

(4) set up Evaluations matrix R: single factor is evaluated from set of factors U, determine that evaluation object concentrates each unit The opinion rating of element；If i-th factor is set out when being evaluated, the opinion rating of index is r_j(r_jValue be 1,2,3,4, 5), r_jValue size determine then there is an Evaluations matrix according to table 1:

$R=\left[\begin{array}{c}{r}_1\\ r_2\\ r_3\\ r_4\end{array}\right]$

Table 1 metrics evaluation grade scale table (design speed is 120km/h)

When evaluating the traffic circulation state in n moment simultaneously, then there is a following multidimensional Evaluations matrix:

$R=\left[\begin{array}{c}{R}_{1j}\\ R_{2j}\\ R_{3j}\\ R_{4j}\end{array}\right]=\left[\begin{array}{cccc}{r}_{11}& r_{12}& \mathrm{...}& r_{1n}\\ r_{21}& r_{22}& \mathrm{...}& r_{2n}\\ r_{31}& r_{32}& \mathrm{...}& r_{3n}\\ r_{41}& r_{42}& \mathrm{...}& r_{4n}\end{array}\right]$

Wherein: R_1j, R_2j, R_3j, R_4jRepresent flow saturation respectively, evaluate travel speed, occupation rate, journey time delay Opinion rating value at moment j；J=1,2 ... n.

(5) fuzzy overall evaluation: when knowing weight sets and Evaluations matrix, the product calculating matrix obtains overall merit Value:

Wherein, bn represents the comprehensive evaluation result value of moment n.

Step 5: evaluation result determines

From step 4, being tried to achieve the comprehensive evaluation result in a certain moment by weight vectors and Evaluations matrix, this result is A certain occurrence between [0,5], determines traffic circulation state by the size of this numerical value, and concrete state interval classification chart is such as Shown in lower:

The interval table of table 2 running status

Comprehensive evaluation result	[0,1.5)	[1.5,2.5)	[2.5,3.5)	[3.5,4.5)	[4.5,5]
						State	Blocking	Crowded	Typically	The most unimpeded	Unimpeded

Finally illustrating, above example is only in order to illustrate technical scheme and unrestricted, although with reference to relatively The present invention has been described in detail by good embodiment, it will be understood by those within the art that, can be to the skill of the present invention Art scheme is modified or equivalent, and without deviating from objective and the scope of the technical program, it all should be contained in the present invention Protection domain in the middle of.

Claims (6)

1. freeway traffic running status fuzzy synthetic appraisement method based on changeable weight, it is characterised in that: include following Step:

Step 1: gather highway data and data are carried out pretreatment；Described data include vehicle checker data and charge number According to；

Step 2: according to the vehicle checker data gathered and charge data Calculation Estimation desired value；Described evaluation index value includes calculating Flow saturation, time occupancy, average travel speed and average travel time are delayed；

Step 3: according to dynamic traffic data, utilize the variance drive principle real-time parameter weight vectors of data；

Step 4: set up dynamic-fuzzy-ovcrall evaluation model according to weight vectors and calculate combining of freeway traffic running status Conjunction evaluation of estimate:

Step 5: according to comprehensive evaluation value freeway traffic running status be evaluated and export evaluation result.

2. freeway traffic running status fuzzy synthetic appraisement method based on changeable weight as claimed in claim 1, its It is characterised by: the data prediction of described step 1 calculates according to following steps:

(11) utilize threshold method that the extraordinary data in vehicle checker data are rejected, specifically comprise the following steps that

Flow threshold q is determined according to below equation:

0≤q≤f_cCT/60；

Wherein: C is road passage capability；T is the time interval of data acquisition；f_cCorrection factor for flow；

Speed v is determined according to below equation:

0≤v≤f_vv₀；

Wherein: v₀Restriction speed for fastlink；f_vCorrection factor for speed；

(12) pretreatment to charge data, specifically comprises the following steps that

Predetermined threshold value TE of journey time is determined according to below equation:

TE=[L/1.5*v₀,24]；

Wherein, TE is effective data intervals；L is road section length；v₀Restriction speed for fastlink；

Judge whether charge data is in predetermined threshold value TE, if it is, charge data is just data, if it is not, then receive Expense data are extraordinary data；

Reject extraordinary data.

3. freeway traffic running status fuzzy synthetic appraisement method based on changeable weight as claimed in claim 1, its It is characterised by: the evaluation index value in described step 2 calculates according to following steps:

Calculating according to below equation of described evaluation index value:

(21) vehicle checker data calculated flow rate saturation and occupation rate are used:

$S=\frac{Q}{C_0};R_t=\frac{1}{T}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{t}_i;$

Wherein: S is link flow saturation；Q is actual vehicle flowrate；C₀Design vehicle flowrate for section；R_tFor time occupancy；T For observation interval；t_iIt is i-th car time of taking detector, i=1,2 ... n；

(22) by the charge ID of expressway tol lcollection data, go out station entrance time and section mileage, obtain the row of each car Sail mileage and journey time, calculate average travel speed and average travel time is delayed:

$D=\frac{L_D}{T_D}=\frac{\underset{i=1}{\overset{n_D}{\mathrm{\Σ}}}{l}_{Di}}{\underset{i=1}{\overset{n_D}{\mathrm{\Σ}}}{t}_{Di}};TD=\frac{1}{n}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\mathrm{td}}_i=\frac{T_{td}}{n}-\frac{l}{v_0};$

Wherein: D is average stroke speed；L_DFor evaluating the total kilometrage of all drivings on period inner evaluation section；T_DFor evaluating the period The total time of interior all vehicle drivings；n_DFor evaluating all driving vehicle numbers on period inner evaluation section；l_DiFor evaluating in the period The mileage of driving vehicle i；t_DiRunning time for the vehicle i that drives a vehicle in evaluating the period；TD is that average travel time is delayed；l For road section length；td_iIt is the journey time of i-th car, T_tdFor total travel time, can be calculated by charge data and obtain；v₀For Pass unimpeded speed, obtains according to the design speed in section；N is the vehicle number summation passed through in observation time.

4. freeway traffic running status fuzzy synthetic appraisement method based on changeable weight as claimed in claim 1, its It is characterised by: the weight vectors in described step 3 calculates according to following steps:

(31) combine sequential weighted average operator TOWA operator and set up the Dynamic Comprehensive Evaluation model of highway:

$y\left(t_k\right)=\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{w}_j\left(t_k\right)x_j\left(t_k\right);$

Wherein: y (t_k) it is linear function；w_j(t_k) it is t_kThe weight in moment, k=1,2 ... n；x_j(t_k) it is t_kThe index in moment is seen Measured value；

(32) linear function is calculatedSum of deviation square maximum；

(33) according to below equation structure index matrix A:

Wherein, m represents assessment indicator system index item number, x_i(t_j) represent assessment indicator system index；

(34) calculate w according to below equation and make function y (t_k) sum of deviation square maximum:

(35) the Maximum characteristic root characteristic of correspondence vector of H is taken, as weight vectors w.

5. freeway traffic running status fuzzy synthetic appraisement method based on changeable weight as claimed in claim 1, its It is characterised by: the dynamic-fuzzy-ovcrall evaluation in described step 4 calculates according to following steps:

(41) set of factors U is set up according to below equation:

U={u₁,u₂,u₃,u₄}={ flow saturation, average stroke speed, occupation rate, journey time is delayed }；

(42) according to below equation foundation evaluation collection V:

V={ is unimpeded, the most unimpeded, typically, crowded, blocking }={ 5,4,3,2,1}；

(43) weight sets W is set up according to below equation:

${w^{\′}}_i=w_i/\underset{i=1}{\overset{4}{\mathrm{\Σ}}}{w}_i;$

Wherein, w={w₁,w₂,w₃,w₄, and weight addition

(44) Evaluations matrix R is set up according to below equation:

$R=\left[\begin{array}{c}{r}_1\\ r_2\\ r_3\\ r_4\end{array}\right];$

Wherein, r_jOpinion rating for index；

Multidimensional Evaluations matrix by following for the opinion rating structure of the traffic circulation state in n moment:

$R=\left[\begin{array}{c}{R}_{1j}\\ R_{2j}\\ R_{3j}\\ R_{4j}\end{array}\right]=\left[\begin{array}{cccc}{r}_{11}& r_{12}& ...& r_{1n}\\ r_{21}& r_{22}& ...& r_{2n}\\ r_{31}& r_{32}& ...& r_{3n}\\ r_{41}& r_{42}& ...& r_{4n}\end{array}\right];$

Wherein: R_1j, R_2j, R_3j, R_4jRespectively represent flow saturation, evaluate travel speed, occupation rate, journey time be delayed time Carve the opinion rating value of j；J=1,2 ... n.

(45) carrying out fuzzy overall evaluation according to below equation, the product calculating matrix according to weight vectors and Evaluations matrix obtains Comprehensive evaluation value:

Wherein, bn represents the comprehensive evaluation result value of moment n.

6. freeway traffic running status fuzzy synthetic appraisement method based on changeable weight as claimed in claim 1, its It is characterised by: the evaluation result in described step 5 is the comprehensive evaluation result tried to achieve by weight vectors and Evaluations matrix, passes through The numerical value of evaluation result determines traffic circulation state.