CN103839411B - A kind of accident impact surface analysis method based on dynamic information - Google Patents

Abstract

The invention provides a kind of accident impact surface analysis method and system based on dynamic information, described method comprises: step 101) judge whether section gets congestion, if the current traffic capacity in section is less than section real-time traffic, then section gets congestion, and performs step 102); Step 102) calculate startup wave loops speed of blocking up; Calculate the passing time of ripple at any section i that block up: start wave loops speed and the passing time estimation accident impact scope of the ripple that blocks up in any section, accident impact time and the transmission path that blocks up based on obtaining blocking up.The present invention adopts dynamic traffic data to achieve the prediction to Urban Road Traffic Accidents coverage in conjunction with road net data, can predict targetedly for particular incident.The data input of the present invention using the data such as coil, Floating Car as prediction, these data have higher accuracy, thus ensure that the accuracy that this patent predicts the outcome in predicted data foundation.

Description

A kind of accident impact surface analysis method based on dynamic information

Technical field

The present invention relates to a kind of accident impact surface analysis method, be specifically related to a kind of accident impact surface analysis system based on dynamic information.

Background technology

Along with the quick rising of China's vehicle guaranteeding organic quantity and infrastructure construction are tending towards saturated, urban traffic pressure is increasing, the stability that traffic flow runs also decreases, and rapid reaction, the normal operation processed for urban transportation of Urban Road Traffic Accidents seem particularly important.

At present, traditional Urban Road Traffic Accidents disposal route mainly simply discovery accident, accident settlement, the coverage for accident is difficult to make and judges accurately and early warning.How fast and accurately accident ground and periphery section coverage to be predicted, and carry out the formulation of accident treatment scheme on this basis, for raising Urban Road Traffic Accidents treatment effeciency, reduce traffic hazard impact and there is vital role.

Patent [201010533022] gives a kind of Urban Road Traffic Accidents coverage defining method based on fixed detector; Patent [201120084414.9] gives the implementation method of a kind of traffic accidents impact prediction and control system; Patent [201110231292.6] proposes a kind of defining method of the expressway traffic accident coverage based on traffic shock wave theory, determines the space-time coverage of traffic hazard after there is traffic hazard on the highway without gateway ring road.

The prediction of Urban Road Traffic Accidents coverage is for making in time targetedly for special traffic accident, accident treatment scheme is significant efficiently.But also there is certain drawback in the prediction at present for Urban Road Traffic Accidents coverage, mainly contains:

(1) Forecasting Methodology for Urban Road Traffic Accidents coverage is less, some is just to Real-Time Monitoring or the simple forecast of Urban Road Traffic Accidents coverage, and not for specific road section, the Urban Road Traffic Accidents impact of special time is predicted targetedly.

(2) Forecasting Methodology of some Urban Road Traffic Accidents coverage needs to install a large amount of fixing monitor, and construction cost is higher.

(3) there are some at present for the method for traffic accidents impact prediction, but have larger difference due to highway and urban transportation, cannot be applied directly in the prediction of Urban Road Traffic Accidents impact.

Summary of the invention

The object of this invention is to provide a kind of method that Urban Road Traffic Accidents coverage based on comprehensive dynamic information is predicted, comprehensive utilization coil history and real time data, Floating Car history and real time data and road net data, make Urban Road Traffic Accidents coverage and predicting accurately, the process for accident provides effective Data support and foundation.

To achieve these goals, the invention provides a kind of accident impact surface analysis method based on dynamic information, described method comprises:

Step 101) judge whether section gets congestion, if the current traffic capacity in section is more than or equal to section real-time traffic, then section does not block up; If the current traffic capacity in section is less than section real-time traffic, then section gets congestion, and performs step 102);

Step 102) adopt following formulae discovery block up ripple start transmission speed;

$V_w=\frac{C_i^{\′}-q_i}{k\left(C_i^{\′}\right)-k\left(q_i\right)}$

Wherein, C _i' represent the traffic capacity of any section I, q _irepresent the real-time traffic of section I, k () represents the traffic density function in section, and this traffic density function is relevant to the flow in section;

Following formulae discovery is adopted to block up the passing time of ripple at any section i:

$t_k=\frac{l_k}{V_{w,k}}$

Wherein, l _krepresent the length of any section k, V _w,krepresent the wave loops speed of blocking up of any section k; Described k and i is equal or not etc.;

Wave loops speed and the passing time estimation accident impact scope of the ripple that blocks up in any section, accident impact time and the transmission path that blocks up is started based on obtaining blocking up.

Optionally, above-mentioned steps 102) comprise further:

Step 102-1) calculate blocking up of any section and start wave loops speed and the passing time of ripple in any section that block up;

Step 102-2) initialization, be specially:

Be i by the section assignment k being numbered k;

The transmission speed V that blocks up in the section of k will be numbered _{w, k}assignment is that blocking up of section k starts wave loops speed V _w;

To be blocked up transmission range l _kassignment is accident point distance crossing, upstream distance L _i';

The transmission time t that blocks up is initialized as the t of ripple at the passing time of section i that block up _i;

Step 102-2) judge whether accident has processed, if the wave loops time t that blocks up is greater than default accident treatment time T, then the ripple that blocks up no longer continues to propagate and terminates in current layer section, performs step 102-4); Otherwise enter next step;

Step 102-3) each section, upstream of calculating section k and section k blocks up transmission speed, and the blocking up the wave loops time of each section, the upstream calculating section k and section k;

And upgrade based on the wave loops time of blocking up in each section obtained the passing time t that blocks up, and return step 102-2), until the passing time that blocks up is greater than the default accident treatment time, enter next step;

Step 102-4) blocking up stops transmitting, the passing time that blocks up in cumulative each section, and each section blocks up wave loops speed and section topology, obtains final statistics.

Optionally, inquire about the coil, Floating Car historical data and the real time data that obtain section, and calculate section real-time traffic based on the data of inquiry.

To achieve these goals, present invention also offers a kind of accident impact surface analysis system based on dynamic information, described system comprises:

Congestion judge module, for judging whether section gets congestion, if the current traffic capacity in section is more than or equal to section real-time traffic, then section does not block up; If the current traffic capacity in section is less than section real-time traffic, then section gets congestion, and starts;

Processing module, for:

Adopt following formulae discovery to block up and start wave loops speed;

$V_w=\frac{C_i^{\′}-q_i}{k\left(C_i^{\′}\right)-k\left(q_i\right)}$

Wherein, C _i' represent the traffic capacity of any section I, q _irepresent the real-time traffic of section I, k () represents the traffic density function in section, and this traffic density function is relevant to the flow in section;

Following formulae discovery is adopted to block up the passing time of ripple at any section i:

$t_k=\frac{l_k}{V_{w,k}}$

Wherein, l _krepresent the length of any section k, V _w,krepresent that blocking up of any section k starts wave loops speed; Described k and i is equal or not etc.;

Wave loops speed and the passing time estimation accident impact scope of the ripple that blocks up in any section, accident impact time and the transmission path that blocks up is started based on obtaining blocking up.

Optionally, above-mentioned processing module comprises further:

First process submodule, starts wave loops speed and the passing time of ripple in any section that block up for calculating blocking up of any section;

Initialization submodule, for completing the initialization of each parameter, is specially:

Be i by the section assignment k being numbered k;

The transmission speed V that blocks up in the section of k will be numbered _{w, k}assignment is that blocking up of section k starts wave loops speed V _w;

To be blocked up transmission range l _kassignment is accident point distance crossing, upstream distance L _i';

The transmission time t that blocks up is initialized as the t of ripple at the passing time of section i that block up _i;

Accident treatment judges submodule, and for judging whether accident has processed, if the wave loops time t that blocks up is greater than default accident treatment time T, then the ripple that blocks up no longer continues to propagate and terminates in current layer section, starts record sub module; Otherwise start the second process submodule;

Second process submodule, each section, the upstream for calculating section k and section k blocks up transmission speed, and the blocking up the wave loops time of each section, the upstream calculating section k and section k;

And upgrade based on the wave loops time of blocking up in each section obtained the passing time t that blocks up, and return step 102-2), until the passing time that blocks up is greater than the default accident treatment time, enter next step;

Record sub module, stops transmitting for blocking up, the passing time that blocks up in cumulative each section, and each section blocks up wave loops speed and section topology.

Optionally, the computing formula of relevant to flow traffic density is:

Then the pass of density and flow is: K=k (Q), k are the corresponding relation formula between K and the Q that obtains based on the computing formula of Q; Wherein, Q is current vehicle flow; K _jit is jam density; The speed of a motor vehicle that passes unimpeded is V _f.

Compared with prior art, technical advantage of the present invention is:

(1) the present invention adopts dynamic traffic data to achieve the prediction to Urban Road Traffic Accidents coverage in conjunction with road net data, can predict targetedly for particular incident.

(2) the data input of the present invention using the data such as coil, Floating Car as prediction, these data have higher accuracy, thus ensure that the accuracy that this patent predicts the outcome in predicted data foundation.

(3) the present invention is by the prediction to Urban Road Traffic Accidents coverage, and the process for Urban Road Traffic Accidents provides effective Data support and foundation.

Accompanying drawing explanation

Fig. 1 is location of accident determination module operation flow;

Fig. 2 is accident impact scope measuring and calculating modular algorithm flow process.

Embodiment

For enabling above-mentioned purpose of the present invention, feature and advantage become apparent more, and below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation.

The main business workflow of Forecasting Methodology of the present invention be divided into location of accident determination module (as Fig. 1) and accident impact range computation module (for flow process A---accident occurs in the centre position, section on non-rapid road, as Fig. 2), analysis accident range effects factor, set up algorithmic rule, accurately calculate range of influence.When there being Urban Road Traffic Accidents information to input, Urban Road Traffic Accidents impact prediction module is according to the real-time accident information of input, and coupling coil, Floating Car history, real time data and road net data are predicted accident impact scope.Two major parameters in accident impact range algorithm flow process---section blocks up passing time t _kdensity K specific algorithm is as follows with a passage is blocked up:

By traffic engineering theory medium velocity, flow, density relationship principle:

Q＝KV（2-1）

:

The relation of road average velocity and flow:

V＝v(Q)（2-4）

The relation of density and flow:

K＝k(Q)（2-5）

(1) calculate section to block up passing time

Calculate jam density K _j

The relation of flow and density:

$Q=V_f(K-\frac{K^2}{K_j})---(2-3)$

The relation of flow and speed:

$Q=K_j(V-\frac{V^2}{V_f})---(2-2)$

Q is current vehicle flow (pcu/h), K _jjam density pcu/km, desirable 80-100, V _f(km/h) be pass unimpeded the speed of a motor vehicle in section, relevant with the highway layout traffic capacity (corresponding relation is shown in annex 1).

By inquiring about the design capacity C of annex and the vehicle velocity V that passes unimpeded _f, the formula 2-2 of utilization can obtain jam density K _j.

The calculating ripple that blocks up starts transmission speed and to block up wave paths section transmission speed

$V_w=\frac{C_i^{\′}-q_i}{k\left(C_i^{\′}\right)-k\left(q_i\right)}---(2-7)$

The ripple that blocks up starts wave loops speed V to block up _wupstream passing, the velocity of propagation in the section, upstream behind crossing is subject to the impact of road saturation degree, and saturation degree is larger, and transmission speed is faster, otherwise less then velocity of propagation is slower.Wave paths of blocking up section transmission speed V _w,kwith the start wave V that blocks up _wrelation:

V _w,k＝ρ _kV _w（2-8）

Wherein, ρ _kkth section congestion in road wave loops conversion factor, relevant to road saturation degree, dimensionless group.

Calculate section passing time

$t_k=\frac{l_k}{V_{w,k}}---(2-9)$

Wherein, t _kh () represents the passing time of ripple in kth section that block up, l _k(km) be kth road section length.

(2) road block density is calculated

Calculate section real-time traffic Q

I. there is coil checker

If Coil Detector flow is Q _coil, coil is L from the distance of downstream intersection _coil.

If a) L _coil< L _thr, then Q=γ Q _coil, γ is link flow conversion factor, is generally greater than 1, L _thrfor distance crossing range estimation threshold value, generally get 30-80m;

If b) L _coil> L _thr, then Q=Q _coil.

Ii. there is Floating Car Road average-speed value

(formula 2.1) is used to calculate Q _floatvalue, makes Q=Q _float.

Iii. there is coil checker and Floating Car velocity amplitude

Q＝η ₁Q _float+η ₂Q _coil（2-6）

η ₁with η ₂for flow weights.

Calculate road block density

Design discharge, maximal rate, jam density triadic relation:

$Q_m=\frac{1}{4}{V}_f{K}_j---(2-10)$

(2-10) is substituted into (2-3):

$Q=V_f(K-\frac{K^2}{\frac{4Q_m}{V_f}})=-\frac{V_f^2}{{4Q}_m}{K}^2+V_{f}K---(2-11)$

Formula (2-11) is solved and can obtain road block density prediction K:

$K=\frac{2Q_m}{V_f}(1+\sqrt{1-\frac{Q}{Q_m}})$

(3) accident impact surface analysis

Accident impact section topology, impact distance ∑ lk is obtained, influence time tu and influence degree K, concentrated expression accident impact scope by iterative algorithm.

There is position in traffic hazard---and comprise crossing, section, ring road entrance and exit etc., as shown in Figure 1, affect velocity of propagation and the spread scope in downstream.But only have studied more complicated in this patent and the situation of common section this patent discussion away from crossing, ring road more than mouth 200m, vehicle enters comparatively stable craspedodrome section, namely the present invention only analyze and research Fig. 1 section between the accident that occurs on the impact in section.

Fig. 2 iterative algorithm flow-interpret:

Step 1: judge whether section i blocks up.If the current traffic capacity C in section _i'>=section real-time traffic q _i, then section does not block up, and iteration terminates; If the current traffic capacity C in section _i' < section real-time traffic q _i, then section blocks up;

Step 2: utilize current vehicle flow (formula 2-2) to calculate section i and reach maximum traffic capacity C _idensity k (the C in ' time _i'), jam density k (q when blocking up _i); Utilize formula 2-7 to calculate and block up and start wave loops speed V _w; Formula 2-9 is utilized to calculate the passing time t of ripple at section i that block up _i;

Step 3: initialization assignment, enters iterative loop.

Step 4: judge whether accident has processed.If t > is accident treatment time T, then the ripple that blocks up no longer continues to propagate and terminates in this layer of section, and record this bang path, iteration terminates; Otherwise enter iterative loop operation.

Step 5: read kth section upstream adjacency matrix n(k), utilize formula 2-9 to calculate respectively to block up the passing time t of ripple on section k and section, upstream thereof _{n(k) i}..., t _{n(k) s}

Step 6: record upgrades blocking up the wave loops time of section k and section, upstream thereof.

Step 7: judge whether the ripple that blocks up arrives its coverage border.The wave loops time t(k if block up) > accident treatment time T, then the ripple that blocks up terminates in this section, and record this bang path, iteration terminates.Otherwise record new t value, transmit the number of plies and increase progressively and get back to step 4.

In addition, present invention also offers a kind of accident impact surface analysis system based on dynamic information, described system comprises:

Congestion judge module, for judging whether section gets congestion, if the current traffic capacity in section is more than or equal to section real-time traffic, then section does not block up; If the current traffic capacity in section is less than section real-time traffic, then section gets congestion, and starts;

Processing module, for:

Adopt following formulae discovery to block up and start wave loops speed;

$V_w=\frac{C_i^{\&prime;}-q_i}{k\left(C_i^{\&prime;}\right)-k\left(q_i\right)}$

Wherein, C _i' represent the traffic capacity of any section I, q _irepresent the real-time traffic of section I, k () represents the traffic density function in section, and this traffic density function is relevant to the flow in section;

Following formulae discovery is adopted to block up the passing time of ripple at any section i:

$t_k=\frac{l_k}{V_{w,k}}$

Wherein, l _krepresent the length of any section k, V _w,krepresent that blocking up of any section k starts wave loops speed; Described k and i is equal or not etc.;

Wave loops speed and the passing time estimation accident impact scope of the ripple that blocks up in any section, accident impact time and the transmission path that blocks up is started based on obtaining blocking up.

Optionally, described processing module comprises further:

First process submodule, starts wave loops speed and the passing time of ripple in any section that block up for calculating blocking up of any section;

Initialization submodule, for completing the initialization of each parameter, is specially:

Be i by the section assignment k being numbered k;

The transmission speed V that blocks up in the section of k will be numbered _{w, k}assignment is that blocking up of section k starts wave loops speed V _w;

To be blocked up transmission range l _kassignment is accident point distance crossing, upstream distance L _i';

The transmission time t that blocks up is initialized as the t of ripple at the passing time of section i that block up _i;

Accident treatment judges submodule, and for judging whether accident has processed, if the wave loops time t that blocks up is greater than default accident treatment time T, then the ripple that blocks up no longer continues to propagate and terminates in current layer section, starts record sub module; Otherwise start the second process submodule;

Second process submodule, each section, the upstream for calculating section k and section k blocks up transmission speed, and the blocking up the wave loops time of each section, the upstream calculating section k and section k;

And upgrade based on the wave loops time of blocking up in each section obtained the passing time t that blocks up, and return step 102-2), until the passing time that blocks up is greater than the default accident treatment time, enter next step;

Record sub module, stops transmitting for blocking up, the passing time that blocks up in cumulative each section, and each section blocks up wave loops speed and section topology.

Further alternative, the computing formula of the traffic density relevant to flow is:

Then the pass of density and flow is: K=k (Q); Wherein, Q is current vehicle flow; K _jit is jam density; The speed of a motor vehicle that passes unimpeded is V _f.

Each symbol related in above-described embodiment is defined as follows:

Road section length L _i; Section lane number L _i,j; Track craspedodrome, left-hand rotation, right-hand rotation zone bit F _i,j; Section turning Probability p _i,t(t=0,1,2 is left straight right); Section design capacity C _i(bicycle road, total traffic capacity is multiplied by number of track-lines), the current traffic capacity C in section _i' (the bottleneck downstream traffic capacity of blocking up); Section real-time traffic q _i(the bottleneck upstream magnitude of traffic flow); Section upstream and downstream average velocity V _{i, 1}, V _{i, 2}; Bottleneck is blocked up wave loops speed V _w(km/ hour); Vehicle density k ₁, k ₂(upstream and downstream) (/km); Road saturation degree λ _k; Accident treatment time T; Accident point is from crossing, upstream distance L _i'.

It should be noted last that, above embodiment is only in order to illustrate technical scheme of the present invention and unrestricted.Although with reference to embodiment to invention has been detailed description, those of ordinary skill in the art is to be understood that, modify to technical scheme of the present invention or equivalent replacement, do not depart from the spirit and scope of technical solution of the present invention, it all should be encompassed in the middle of right of the present invention.

Claims (4)

1., based on an accident impact surface analysis method for dynamic information, described method comprises:

Step 101) judge whether section gets congestion, if the current traffic capacity in section is more than or equal to section real-time traffic, then section does not block up; If the current traffic capacity in section is less than section real-time traffic, then section gets congestion, and performs step 102);

Step 102) adopt following formulae discovery block up ripple start transmission speed;

$V_w=\frac{C_i^{\&prime;}-q_i}{k\left(C_i^{\&prime;}\right)-k\left(q_i\right)}$

Wherein, C ' _irepresent the traffic capacity of any section I, q _irepresent the real-time traffic of section I, k () represents the traffic density function in section, and this traffic density function is relevant to the flow in section;

Following formulae discovery is adopted to block up the passing time of ripple at any section i:

$t_k=\frac{l_k}{V_{w,k}}$

Wherein, l _krepresent the length of any section k, V _w,krepresent the wave loops speed of blocking up of any section k; Described k and i is equal or not etc.;

Wave loops speed and the passing time estimation accident impact scope of the ripple that blocks up in any section, accident impact time and the transmission path that blocks up is started based on obtaining blocking up;

Wherein, described step 102) comprise further:

Step 102-1) calculate blocking up of any section and start wave loops speed and the passing time of ripple in any section that block up;

Step 102-2) initialization, be specially:

Be i by the section assignment k being numbered k;

The transmission speed V that blocks up in the section of k will be numbered _{w, k}assignment is that blocking up of section k starts wave loops speed V _w;

To be blocked up transmission range l _kassignment is accident point distance crossing, upstream distance L _i';

The transmission time t that blocks up is initialized as the t of ripple at the passing time of section i that block up _i;

Step 102-2) judge whether accident has processed, if the wave loops time t that blocks up is greater than default accident treatment time T, then the ripple that blocks up no longer continues to propagate and terminates in current layer section, performs step 102-4); Otherwise enter next step;

Step 102-3) each section, upstream of calculating section k and section k blocks up transmission speed, and the blocking up the wave loops time of each section, the upstream calculating section k and section k;

And upgrade based on the wave loops time of blocking up in each section obtained the passing time t that blocks up, and return step 102-2), until the passing time that blocks up is greater than the default accident treatment time, enter next step;

Step 102-4) blocking up stops transmitting, the passing time that blocks up in cumulative each section, and each section blocks up wave loops speed and section topology, obtains final statistics.

2. the accident impact surface analysis method based on dynamic information according to claim 1, is characterized in that, inquires about the coil, Floating Car historical data and the real time data that obtain section, and calculates section real-time traffic based on the data of inquiry.

3., based on an accident impact surface analysis system for dynamic information, described system comprises:

Congestion judge module, for judging whether section gets congestion, if the current traffic capacity in section is more than or equal to section real-time traffic, then section does not block up; If the current traffic capacity in section is less than section real-time traffic, then section gets congestion, and starts;

Processing module, for:

Adopt following formulae discovery to block up and start wave loops speed;

$V_w=\frac{C_i^{\&prime;}-q_i}{k\left(C_i^{\&prime;}\right)-k\left(q_i\right)}$

Wherein, C ' _irepresent the traffic capacity of any section I, q _irepresent the real-time traffic of section I, k () represents the traffic density function in section, and this traffic density function is relevant to the flow in section;

Following formulae discovery is adopted to block up the passing time of ripple at any section i:

$t_k=\frac{l_k}{V_{w,k}}$

Wherein, l _krepresent the length of any section k, V _w,krepresent that blocking up of any section k starts wave loops speed; Described k and i is equal or not etc.;

Wave loops speed and the passing time estimation accident impact scope of the ripple that blocks up in any section, accident impact time and the transmission path that blocks up is started based on obtaining blocking up;

Wherein, described processing module comprises further:

First process submodule, starts wave loops speed and the passing time of ripple in any section that block up for calculating blocking up of any section;

Initialization submodule, for completing the initialization of each parameter, is specially:

Be i by the section assignment k being numbered k;

The transmission speed V that blocks up in the section of k will be numbered _{w, k}assignment is that blocking up of section k starts wave loops speed V _w;

To be blocked up transmission range l _kassignment is accident point distance crossing, upstream distance L _i';

The transmission time t that blocks up is initialized as the t of ripple at the passing time of section i that block up _i;

Accident treatment judges submodule, and for judging whether accident has processed, if the wave loops time t that blocks up is greater than default accident treatment time T, then the ripple that blocks up no longer continues to propagate and terminates in current layer section, starts record sub module; Otherwise start the second process submodule;

Second process submodule, each section, the upstream for calculating section k and section k blocks up transmission speed, and the blocking up the wave loops time of each section, the upstream calculating section k and section k;

And upgrade the passing time t that blocks up, until the passing time that blocks up is greater than the default accident treatment time based on the wave loops time of blocking up in each section obtained;

Record sub module, stops transmitting for blocking up, the passing time that blocks up in cumulative each section, and each section blocks up wave loops speed and section topology.

4. the accident impact surface analysis system based on dynamic information according to claim 3, it is characterized in that, the computing formula of the traffic density relevant to flow is: then the pass of density and flow is: K=k (Q);

Wherein, Q is current vehicle flow; K _jit is jam density; The speed of a motor vehicle that passes unimpeded is V _f.