CN103680150A - Method for determining traffic incident impact areas and durations on basis of coil detection - Google Patents

Abstract

The invention relates to a method for determining traffic incident impact areas and durations on the basis of coil detection. The method includes enabling coils to acquire traffic flow and spot average speed data at preset intervals when traffic incidents occur, and updating queuing lengths of road sections; updating queuing lengths of various access roads when the queuing lengths of the road sections are larger than the distances from traffic incident occurrence spots to intersections; updating dissipation lengths of the road sections and the queuing lengths of the various access roads when the traffic incidents are completed; updating dissipation lengths and the queuing lengths of the various access roads when the dissipation lengths of the road sections are larger than the distances from the traffic incident occurrence spots to the intersections; determining that the traffic incidents are completely finished when the dissipation lengths of the various access roads are larger than the corresponding queuing lengths, and determining the incident impact areas and the durations. Compared with the prior art, the method has the advantages that development of the traffic incidents is observed in real time by the aid of the coils, accordingly, the traffic incident impact areas and the impact durations can be accurately estimated, and a decision basis can be provided for traffic control and management.

Description

Traffic events coverage and the duration based on coil, detected are determined method

Technical field

The present invention relates to traffic control and management field, especially relate to a kind of traffic events coverage and duration of detecting based on coil and determine method.

Background technology

Follow the fast development of urban economy, social activities, and the acceleration of urbanization process, the challenge that China's urban transportation faces is also deepening constantly: in short supply, the increase of Pressure on Energy of land resource is, the variation of social demand etc.Around scientific and requirement that become more meticulous, the level of decision-making of urban highway traffic planning and management is in urgent need to be improved.And on the other hand, along with the development of intelligent transport technology and the foundation of traffic information system, for urban planning and management department provides abundant traffic data resource, how to make full use of several data and launch the analysis of various dimensions, for decision-making provides technical support, it is the emphasis that management and technician pay close attention to.

Traffic control and management to traffic events decision analysis work in, the coverage of traffic events and influence time are the important parameters of reaction traffic events degree, when to traffic events issue vehicle guidance information, need to input the coverage of traffic events; In emergency relief vehicle path planning, determining of coverage is also the basis of work; In traffic events signal controlling, determining of coverage and time produces material impact to the decision-making of control program.

Traditional traffic events coverage and time obtaining method are that theoretical modeling calculates, mainly to utilize traffic wave pattern and waiting line theory theory, single section or crossing are analyzed, set up model and utilize field observation data to carry out check analysis, when model calculates hypotheses be the parameters such as the flow in bottleneck and upstream and downstream section thereof and density on the time for being even value on constant, space.And in actual traffic, the flow in section is random fluctuation, and the vehicle that density is also brought due to the signal period starting of repeatedly stopping changes, and the flow in bottleneck road upstream, bottleneck road downstream and density is fluctuation in time not only, also with place, fluctuate, and non-homogeneous value.Classic method can not obtain data in real time, only has the average data that a certain instantaneous traffic data is used as to whole process to calculate traffic wave pattern, has limitation, has difference with actual conditions.Therefore the result of calculating is difficult to coverage and the time of accurate response traffic events, is unfavorable for the rational of traffic control and management strategy.

Along with the development of intelligent transport technology, increasing city builds advanced transportation information service systems, and traffic data collection and treatment technology come into one's own gradually.Coil image data has wide coverage, accuracy is high, actual effect is strong and can Continuous Observation etc. advantage.Data after gathering are cleaned, after repairing, can analyze the master data that obtains traffic circulation situation, carry out on this basis data processing and modeling analysis, can obtain coverage and the time of traffic events.

In the research application of city signal traffic control system, mainly with the SCOOT system of Britain and Australian SCATS system, take as the leading factor, by near the loop wire coil being laid in crossing, gather traffic master data, intersection signal situation is adjusted in the variation of self-adaptation traffic, and master data is transferred to information center, for the decision-making of traffic control and management provides support.China listd and has studied " urban transportation real-time adaptive control system " in the enforcement period of the seventh five-year plan, and China city mainly adopts foreign system to use SCOOT system as Beijing at present, and SCATS system is used in Shanghai.

On the whole, the application of China's city signal traffic control system is comparatively ripe, but how not rationally application of the data that collect for control system is combined existing traffic data with traffic analysis method, for traffic control and management provides foundation, need a large amount of positive researches.

Summary of the invention

Object of the present invention is exactly to provide a kind of traffic events coverage and duration of detecting based on coil to determine method in order to overcome the defect of above-mentioned prior art existence.

Object of the present invention can be achieved through the following technical solutions: a kind of traffic events coverage and duration of detecting based on coil determined method, it is characterized in that, when traffic events occurs, be laid near the coil in crossing every magnitude of traffic flow of predetermined time interval collection and place average speed data, from traffic, start to finishing completely, determine that events affecting scope and duration comprise the following steps:

Step 1, the data that gather according to coil, utilize traffic ripple computation model to calculate to occur from event origination point to the event crossing the traffic wave-wave speed ω in section, calculates thus the newly-increased queue length Δ L in this section after this time interval _r, and to section queue length L _rupgrade;

Step 2, as section queue length L _rwhile being greater than traffic events origination point to the distance X of crossing, each entrance driveway diffusion to crossing of queuing up, the parking wave-wave speed ω that utilizes parking ripple computation model to calculate to propagate to each entrance driveway from crossing _si, calculate thus each entrance driveway queue length Δ L increasing newly after this time interval _i, and to each entrance driveway queue length L _iupgrade;

When step 3, traffic events finish, utilize the first startup ripple computation model calculating event that the startup wave-wave speed ω in section occurs _b, calculate thus newly-increased dissipation length Δ S after this time interval, and section dissipation length S is upgraded, continue to upgrade each entrance driveway queue length L according to the method for step 2 simultaneously _i;

Step 4, when section dissipation length S is greater than traffic events origination point to the distance X of crossing, utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade, continue to upgrade each entrance driveway queue length L according to the method for step 2 simultaneously _i;

Step 5, as each entrance driveway dissipation length S _iall be greater than corresponding queue length L _itime, traffic events finishes completely, and events affecting scope comprises queue length when each entrance driveway dissipation length of crossing is greater than queue length first; Incident duration starts for dissipating from event to be greater than the maximum duration of queue length to each entrance driveway dissipation length.

Traffic ripple computation model described in step 1 is,

$\mathrm{\ω}=\frac{v_{t1}{v}_{t2}(q_2-q_1)}{v_{t1}{q}_2-v_{t2}{q}_1}\·\frac{1}{\left({1+c.v}^2\right)}$

In formula, q ₁for the vehicle flowrate of upstream, q ₂for the vehicle flowrate in downstream, v _t1for the place average speed of upstream, v _t2for the place average speed in downstream, the coefficient of variation that c.v is overall speed, span is [0.08,0.17].

Parking ripple computation model described in step 2 is,

${\mathrm{\ω}}_{\mathrm{si}}=\frac{{-q}_{1i}{v}_{t1i}}{v_{t1i}{k}_i-q_{1i}\left({1+c.v}^2\right)}$

In formula, q _1ifor the vehicle flowrate of queue upstream, crossing, v _tlifor the place average speed of upstream, k _ifor jamming density, the coefficient of variation that c.v is overall speed, span is [0.08,0.17].

Each entrance driveway queue length Δ L increasing newly after this time interval of calculating described in step 2 _i, and to each entrance driveway queue length L _iupgrade specifically and comprise the following steps:

(21) judgement section queue length L _rwhether be greater than traffic events origination point to the distance X of crossing, be to perform step (22), otherwise return to step 1;

(22) judgement section queue length L _rwhether being greater than first traffic events origination point to the distance X of crossing, is to perform step (23), otherwise execution step (25);

(23) utilize parking ripple computation model to calculate from crossing to the parking wave-wave speed ω of each entrance driveway propagation _si, the time t required according to vehicle queue to crossing ₁and traffic events is from occurring to this end of scan spent time T ₁, obtain t excess time ₂, calculate at t excess time ₂the queue length Δ L that each entrance driveway of interior crossing is newly-increased _i;

Wherein,

ΔL _i＝t ₂ω _si＝(T ₁-t ₁)ω _si

t1＝(X-L _r-|ω|*Δt)/|ω|

(24) upgrade each entrance driveway queue length of crossing L after this sweep spacing _i, execution step (26);

Wherein, for event, the entrance driveway queue length L that section direction is identical occurring ₁for,

L ₁＝L _r+ΔL ₁

In formula, Δ L ₁for there is with event the entrance driveway queue length that section direction is identical in newly-increased;

For other entrance driveway queue lengths of crossing L _ifor,

L _i＝ΔL _i

(25) utilize parking ripple computation model to calculate from crossing to the parking wave-wave speed ω of each entrance driveway propagation _si, upgrade each entrance driveway queue length of crossing L after this sweep spacing _i;

Wherein,

L _i＝L _i+ΔL _i＝L _i+Δt*ω _si

In formula, the L on the equal sign left side _ifor this coil scanning is upgraded rear crossing entrance driveway queue length, the L on equal sign the right _ifor rear certain entrance driveway queue length, Δ L are upgraded in coil scanning last time _ifor certain newly-increased entrance driveway queue length;

(26) whether traffic events finishes, and is to perform step 3, otherwise returns to step (22) after the predetermined time interval Δ t of interval.

Each entrance driveway dissipation length Δ S increasing newly after this time interval of calculating described in step 4 _i, and to each entrance driveway dissipation length S _iupgrade specifically and comprise the following steps:

(41) judge that whether section dissipation length S is greater than traffic events origination point to the distance X of crossing, is to perform step (42), otherwise returns to step 3;

(42) judge whether section dissipation length S is greater than traffic events origination point first to the distance X of crossing, is to perform step (43), otherwise return to step (44);

(43) utilize and start the startup wave-wave speed ω that ripple computation model calculates each entrance driveway of crossing _bi, calculate thus and now ask newly-increased each entrance driveway dissipation length Δ S behind interval _i, and to each entrance driveway dissipation length S _iupgrade execution step (45);

Wherein, for event, the entrance driveway dissipation length S that section direction is identical occurring ₁for,

S ₁＝S+ΔS ₁＝S+|ω _b1|*Δt

In formula, Δ S ₁for there is with event the entrance driveway dissipation length that section direction is identical in newly-increased;

For crossing other entrance driveway dissipation length S _ifor,

S _i＝ΔS _i＝|ω _bi|*Δt

(44) utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade;

Wherein,

S _i＝S _i+ΔS _i＝S _i+|ω _bi|*Δt

In formula, the S on the equal sign left side _ifor this coil scanning is upgraded rear crossing entrance driveway dissipation length, the S on equal sign the right _ifor rear certain entrance driveway dissipation length is upgraded in coil scanning last time;

(45) judgement crossing each entrance driveway dissipation length S _iwhether be all greater than each entrance driveway queue length L _i, be to perform step 5, otherwise return to step (42) after the Preset Time interval of delta t of interval.

Described in step 3 first starts ripple computation model,

ω _b＝v _f

In formula, v _ffor starting the free flow speed in section, ripple place, get the maximum speed limit in this section herein.

Described in step 4 second starts ripple computation model,

${\mathrm{\ω}}_{\mathrm{bi}}=v_{\mathrm{fi}}*\frac{g_i}{C_i}$

In formula, v _fifor starting the free flow speed in section, ripple place, g _ifor starting the green time in crossing inlet road, ripple place, C _ifor starting the signal period of crossing, ripple place.

Incident duration t described in step 5 is,

t＝(L _i-|ω _si|*Δt-S _i+|ω _bi|*Δt)/(|ω _bi|-|ω _si|)

In formula, S _ifor starting ripple, last catch up with the queue clearance length in parking ripple direction, ω _bifor the startup wave-wave speed of this entrance driveway, L _ifor this entrance driveway queue length, ω _sjparking wave-wave speed for this entrance driveway.

Compared with prior art, the present invention improves conventional traffic ripple theory, utilizes coil to detect data traffic events development is carried out to real-time monitored, by continuous renewal, detects data, accurately estimate coverage and the influence time of traffic events, for traffic control and management provides decision-making foundation.

Accompanying drawing explanation

Fig. 1 calculates the process flow diagram of section queue length and crossing queue length after traffic events of the present invention occurs;

Fig. 2 is that the present invention starts the final coverage of calculating and the process flow diagram of final duration in the ripple time;

Fig. 3 is embodiment of the present invention verification model basis road network figure.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

As shown in Figure 1, traffic events calculates section queue length L after occurring _rwith each entrance driveway queue length of crossing L _xicomprise the following steps:

(101) be laid near the coil in crossing every magnitude of traffic flow of predetermined time interval Δ t collection and place average speed data, the data that gather according to coil, utilize traffic ripple computation model to calculate to occur from event origination point to the event crossing the traffic wave-wave speed ω in section, calculate thus the newly-increased queue length Δ L in this section after this time interval _r, and to section queue length L _rupgrade;

Wherein,

L _r＝L _r+ΔL _r＝L _r+|ω|*Δt

In formula, the L on the equal sign left side _rfor the section queue length after this coil scanning renewal, the L on equal sign the right _rfor the section queue length after coil scanning renewal last time,

$\mathrm{\ω}=\frac{v_{t1}{v}_{t2}(q_2-q_1)}{v_{t1}{q}_2-v_{t2}{q}_1}\·\frac{1}{\left({1+c.v}^2\right)}$

In formula, q ₁for the vehicle flowrate of event generation upstream, section, q ₂for the vehicle flowrate in downstream, v _t1for the place average speed of upstream, v _t2for the place average speed in downstream, the coefficient of variation that c.v is overall speed, span is [0.08,0.17];

(102) judgement section queue length L _rwhether be greater than traffic events origination point to the distance X of crossing, be to perform step (103), otherwise continue execution step (101);

(103) judgement section queue length L _rwhether being greater than first traffic events origination point to the distance X of crossing, is to perform step (104), otherwise execution step (106);

(104) utilize parking ripple computation model to calculate from crossing to the parking wave-wave speed ω of each entrance driveway propagation _si, the time t required according to vehicle queue to crossing ₁and traffic events is from occurring to this end of scan spent time T ₁, obtain t excess time ₂, calculate at t excess time ₂the queue length ω L that each entrance driveway of interior crossing is newly-increased _i;

Wherein,

ΔL _i＝t ₂ω _si＝(T ₁-t ₁)ω _si

t1＝(X-L _r-|ω|*Δt)/|ω|

Described parking ripple computation model is,

${\mathrm{\ω}}_{\mathrm{si}}=\frac{{-q}_{1i}{v}_{t1i}}{v_{t1i}{k}_i-q_{1i}\left({1+c.v}^2\right)}$

In formula, q _1ifor the vehicle flowrate of queue upstream, crossing, v _t1ifor the place average speed of upstream, k _ifor jamming density, the coefficient of variation that c.v is overall speed, span is [0.08,0.17];

(105) upgrade each entrance driveway queue length of crossing L after this sweep spacing _i, after the predetermined time interval Δ t of interval, return to step (103);

Wherein, for event, the entrance driveway queue length L that section direction is identical occurring ₁for,

L ₁＝L _r+ΔL ₁

In formula, Δ L ₁for there is with event the entrance driveway queue length that section direction is identical in newly-increased;

For other entrance driveway queue lengths of crossing L _ifor,

L _i＝ΔL _i

(106) utilize parking ripple computation model to calculate from crossing to the parking wave-wave speed ω of each entrance driveway propagation _si, upgrade each entrance driveway queue length of crossing L after this sweep spacing _i, after the predetermined time interval Δ t of interval, return to step (103);

L _i＝L _i+ΔL _i＝L _i+Δt*ω _si；

In formula, the L on the equal sign left side _ifor this coil scanning is upgraded rear crossing entrance driveway queue length, the L on equal sign the right _ifor rear certain entrance driveway queue length, Δ L are upgraded in coil scanning last time _ifor certain newly-increased entrance driveway queue length.

As shown in Figure 2, when traffic events finishes, ripple calculates events affecting scope in the time and incident duration comprises the following steps starting:

(201) be laid near the coil in crossing every magnitude of traffic flow of predetermined time interval Δ t collection and place average speed data, the data that gather according to coil, utilize the first startup ripple computation model calculating event that the startup wave-wave speed ω in section occurs _b, calculate thus newly-increased dissipation length Δ S after this time interval, and section dissipation length S upgraded;

Described first starts ripple computation model is,

ω _b＝v _f

In formula, v _ffor starting the free flow speed in section, ripple place, get the maximum speed limit in this section herein;

(202) judge whether section dissipation length S is greater than traffic events origination point to the distance X of crossing, is to perform step (203), otherwise return to step (201);

(203) judge whether section dissipation length S is greater than traffic events origination point first to the distance X of crossing, is to perform step (204), otherwise return to step (205);

(204) data that gather according to coil, utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade execution step (206);

Wherein, for event, the entrance driveway dissipation length S that section direction is identical occurring ₁for,

S ₁＝S+ΔS ₁＝S+|ω _b1|*Δt

In formula, Δ S ₁for there is with event the entrance driveway dissipation length that section direction is identical in newly-increased;

For crossing other entrance driveway dissipation length S _ifor,

S _i＝ΔS _i＝|ω _bi|*Δt

Described second starts ripple computation model is,

${\mathrm{\ω}}_{\mathrm{bi}}=v_{\mathrm{fi}}*\frac{g_i}{C_i}$

In formula, v _fifor starting the free flow speed in section, ripple place, g _ifor starting the green time in crossing inlet road, ripple place, C _ifor starting the signal period of crossing, ripple place;

(205) data that gather according to coil, utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade;

Wherein,

S _i＝S _i+ΔS _i＝S _i+|ω _bi|*Δt

In formula, the S on the equal sign left side _ifor this coil scanning is upgraded rear crossing entrance driveway dissipation length, the S on equal sign the right _ifor rear certain entrance driveway dissipation length is upgraded in coil scanning last time;

(206) judgement crossing each entrance driveway dissipation length S _iwhether be greater than each entrance driveway queue length L _i, be to perform step (207), otherwise return to step (203) after the Preset Time interval of delta t of interval;

(207) events affecting scope comprises queue length when each entrance driveway dissipation length of crossing is greater than queue length first; Incident duration starts for dissipating from event to be greater than the maximum duration of queue length to each entrance driveway dissipation length;

Wherein, described incident duration t is,

t＝(L _i-|ω _si|*Δt-S _i+|ω _bi|*Δt)/(|ω _bi|-|ω _si|)

In formula, S _ifor starting ripple, last catch up with the queue clearance length in parking ripple direction, ω _bifor the startup wave-wave speed of this entrance driveway, L _ifor this entrance driveway queue length, ω _sjparking wave-wave speed for this entrance driveway.

Embodiment:

Utilize microscopic simulation software VISSIM to set up verification model road network, and at crossing layout magnetic test coil, simulating actual conditions, the predetermined time interval of coil scanning is 30s, VISSIM is carried out to COM exploitation, calculate events affecting scope and duration, it is as shown in table 1 that result is recorded in traffic ripple emulation queuing.

Table 1 traffic ripple emulation queuing record sheet

Simulation time (s)	L 1(m)	Lx 1(m)	L 2(m)	Lx 2(m)	L 3(m)	Lx 3(m)
							480	0.0	0.0	0.0	0.0	0.0	0.0
510	22.2	0.0	0.0	0.0	0.0	0.0

Simulation time (s)	L 1(m)	Lx 1(m)	L 2(m)	Lx 2(m)	L 3(m)	Lx 3(m)
							540	29.9	0.0	0.0	0.0	0.0	0.0
570	48.6	0.0	0.0	0.0	0.0	0.0
							600	55.0	0.0	0.0	0.0	0.0	0.0
630	74.9	0.0	0.0	0.0	0.0	0.0
							660	142.2	0.0	0.0	0.0	0.0	0.0
690	158.0	0.0	0.0	0.0	0.0	0.0
							720	168.7	0.0	0.0	0.0	0.0	0.0
750	185.8	0.0	0.0	0.0	0.0	0.0
							780	238.0	0.0	0.0	0.0	0.0	0.0
810	255.2	0.0	0.0	0.0	0.0	0.0
							840	264.2	0.0	0.0	0.0	0.0	0.0
870	281.2	0.0	0.0	0.0	0.0	0.0
							900	314.2	0.0	0.0	0.0	0.0	0.0
930	344.4	0.0	9.1	0.0	5.0	0.0
							960	350.7	0.0	43.3	0.0	41.2	0.0
990	363.7	0.0	65.5	0.0	68.5	0.0
							1020	371.4	0.0	67.6	0.0	79.4	0.0
1050	373.9	0.0	102.0	0.0	118.4	0.0
							1080	384.2	0.0	110.5	0.0	129.1	0.0
1110	399.9	250.0	128.0	0.0	137.6	0.0
							1140	406.2	321.0	145.6	0.0	169.7	0.0
1170	416.5	571.0	163.1	0.0	182.7	0.0
							1200	424.2	654.3	180.5	0.0	195.5	0.0
1230	435.8	654.3	180.5	208.3	213.4	208.3
							1260	446.1	654.3	217.5	291.7	255.0	291.7

In table 1, L ₁be 1 direction queue length, L ₂, L ₃be 2,3 direction queue lengths, Lx _i, be queue clearance length, i=1,2,3 representative be section direction.As shown in Figure 3, there is traffic events in E place.

As can be seen from Table 1, after some event occurs, queue up at first at L ₁on the section of direction, produce queue length L in section when simulation time is 930s ₁=344.4m is greater than the distance X=320m between spot and crossing, upstream first, now illustrates that vehicle queue has spread to crossing, upstream, and the road of other both directions also should produce queuing, and L now ₂=9.1m, L ₃=5.0m, has illustrated that queuing occurs at the road of other directions of crossing;

When simulation time is 1080s, some event finishes, and starts ripple and starts to produce, and can obtain the coverage of event in time T 1=1080-480=600s; L ₁=384.2m, L ₂=110.5m, L ₃=129.1m;

When simulation time is 1170s, queue clearance length L x ₁=571.0m is greater than section queue length L first ₁=416.5m, illustrates a certain moment in simulation time 1140s to 1170s, starts ripple and catch up with L ₁the parking ripple of direction, the queuing of this direction is dissipated completely;

When simulation time is 1230s, queue clearance length L x ₂=208.3m is greater than crossing queue length L first ₂=180.5m, illustrates a certain moment in simulation time 1200s to 1230s, starts ripple and catch up with L ₂the parking ripple of direction, the queuing of this direction is dissipated completely;

When simulation time is 1260s, queue clearance length L x ₃=291.7m is greater than crossing queue length L first ₃=255.0m, illustrates a certain moment in simulation time 1230s to 1260s, starts ripple and catch up with L ₃the parking ripple of direction, the queuing of this direction is dissipated completely.

According to queue clearance correction formula, obtain an event and finish the actual 175s of being of rear queue clearance spent time, the long lasting effect time is T2=175s, and total influence time T of some event is T=T1+T2=775s, and some events affecting scope is: L ₁=416.5m, L ₂=180.5m, L ₃=255.0m.

Claims (8)

1. traffic events coverage and the duration of detecting based on coil determined method, it is characterized in that, when traffic events occurs, be laid near the coil in crossing every magnitude of traffic flow of predetermined time interval collection and place average speed data, from traffic, start to finishing completely, determine that events affecting scope and duration comprise the following steps:

Step 1, the data that gather according to coil, utilize traffic ripple computation model to calculate to occur from event origination point to the event crossing the traffic wave-wave speed ω in section, calculates thus the newly-increased queue length Δ L in this section after this time interval _r, and to section queue length L _rupgrade;

Step 2, as section queue length L _rwhile being greater than traffic events origination point to the distance X of crossing, each entrance driveway diffusion to crossing of queuing up, the parking wave-wave speed ω that utilizes parking ripple computation model to calculate to propagate to each entrance driveway from crossing _si, calculate thus each entrance driveway queue length Δ L increasing newly after this time interval _i, and to each entrance driveway queue length L _iupgrade;

When step 3, traffic events finish, utilize the first startup ripple computation model calculating event that the startup wave-wave speed ω in section occurs _b, calculate thus newly-increased dissipation length Δ S after this time interval, and section dissipation length S is upgraded, continue to upgrade each entrance driveway queue length L according to the method for step 2 simultaneously _i;

Step 4, when section dissipation length S is greater than traffic events origination point to the distance X of crossing, utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade, continue to upgrade each entrance driveway queue length L according to the method for step 2 simultaneously _i;

Step 5, as each entrance driveway dissipation length S _iall be greater than corresponding queue length L _itime, traffic events finishes completely, and events affecting scope comprises queue length when each entrance driveway dissipation length of crossing is greater than queue length first; Incident duration starts for dissipating from event to be greater than the maximum duration of queue length to each entrance driveway dissipation length.

2. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that, the traffic ripple computation model described in step 1 is,

$\mathrm{\ω}=\frac{v_{t1}{v}_{t2}(q_2-q_1)}{v_{t1}{q}_2-v_{t2}{q}_1}\·\frac{1}{\left({1+c.v}^2\right)}$

In formula, q ₁for the vehicle flowrate of upstream, q ₂for the vehicle flowrate in downstream, v _t1for the place average speed of upstream, v _t2for the place average speed in downstream, the coefficient of variation that c.v is overall speed, span is [0.08,0.17].

3. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that, the parking ripple computation model described in step 2 is,

${\mathrm{\ω}}_{\mathrm{si}}=\frac{{-q}_{1i}{v}_{t1i}}{v_{t1i}{k}_i-q_{1i}\left({1+c.v}^2\right)}$

In formula, q _1ifor the vehicle flowrate of queue upstream, crossing, v _t1ifor the place average speed of upstream, k _ifor jamming density, the coefficient of variation that c.v is overall speed, span is [0.08,0.17].

4. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that newly-increased each entrance driveway queue length Δ L after this time interval of calculating described in step 2 _i, and to each entrance driveway queue length L _iupgrade specifically and comprise the following steps:

(21) judgement section queue length L _rwhether be greater than traffic events origination point to the distance X of crossing, be to perform step (22), otherwise return to step 1;

(22) judgement section queue length L _rwhether being greater than first traffic events origination point to the distance X of crossing, is to perform step (23), otherwise execution step (25);

(23) utilize parking ripple computation model to calculate from crossing to the parking wave-wave speed ω of each entrance driveway propagation _si, the time t required according to vehicle queue to crossing ₁and traffic events is from occurring to this end of scan spent time T ₁, obtain t excess time ₂, calculate at t excess time ₂the queue length Δ L that each entrance driveway of interior crossing is newly-increased _i;

Wherein,

ΔL _i＝t ₂ω _si＝(T ₁-t ₁)ω _si

t1＝(X-L _r+|ω|*Δt)/|ω|

(24) upgrade each entrance driveway queue length of crossing L after this sweep spacing _i, execution step (26);

Wherein, for event, the entrance driveway queue length L that section direction is identical occurring ₁for,

L ₁＝L _r+ΔL ₁

In formula, Δ L ₁for there is with event the entrance driveway queue length that section direction is identical in newly-increased:

For other entrance driveway queue lengths of crossing L _ifor,

L _i＝ΔL _i

(25) utilize parking ripple computation model to calculate from crossing to the parking wave-wave speed ω of each entrance driveway propagation _si, upgrade each entrance driveway queue length of crossing L after this sweep spacing _i;

Wherein,

L _i＝L _i+ΔL _i＝L _i+Δt*ω _si

In formula, the L on the equal sign left side _ifor this coil scanning is upgraded rear crossing entrance driveway queue length, the L on equal sign the right _ifor rear certain entrance driveway queue length, Δ L are upgraded in coil scanning last time _ifor certain newly-increased entrance driveway queue length;

(26) whether traffic events finishes, and is to perform step 3, otherwise returns to step (22) after the predetermined time interval Δ t of interval.

5. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that newly-increased each entrance driveway dissipation length Δ S after this time interval of calculating described in step 4 _i, and to each entrance driveway dissipation length S _iupgrade specifically and comprise the following steps:

(41) judge that whether section dissipation length S is greater than traffic events origination point to the distance X of crossing, is to perform step (42), otherwise returns to step 3;

(42) judge whether section dissipation length S is greater than traffic events origination point first to the distance X of crossing, is to perform step (43), otherwise return to step (44);

(43) utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade execution step (45);

Wherein, for event, the entrance driveway dissipation length S that section direction is identical occurring ₁for,

S ₁＝S+ΔS ₁＝S+|ω _b1|*Δt

In formula, Δ S ₁for there is with event the entrance driveway dissipation length that section direction is identical in newly-increased;

For crossing other entrance driveway dissipation length S _ifor,

S _i＝ΔS _i＝|ω _bi|*Δt

(44) utilize the second startup ripple computation model to calculate the startup wave-wave speed ω of each entrance driveway of crossing _bi, calculate thus each entrance driveway dissipation length Δ S increasing newly after this time interval _i, and to each entrance driveway dissipation length S _iupgrade;

Wherein,

S _i＝S _i+ΔS _i＝S _i+|ω _bi|*Δt

In formula, the S on the equal sign left side _ifor this coil scanning is upgraded rear crossing entrance driveway dissipation length, the S on equal sign the right _ifor rear certain entrance driveway dissipation length is upgraded in coil scanning last time;

(45) judgement crossing each entrance driveway dissipation length S _iwhether be all greater than each entrance driveway queue length L _i, be to perform step 5, otherwise return to step (42) after the Preset Time interval of delta t of interval.

6. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that, first described in step 3 starts ripple computation model and be,

ω _b＝v _f

In formula, v _ffor starting the free flow speed in section, ripple place, get the maximum speed limit in this section herein.

7. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that, second described in step 4 starts ripple computation model and be,

${\mathrm{\ω}}_{\mathrm{bi}}=v_{\mathrm{fi}}*\frac{g_i}{C_i}$

In formula, v _fifor starting the free flow speed in section, ripple place, g _ifor starting the green time in crossing inlet road, ripple place, C _ifor starting the signal period of crossing, ripple place.

8. a kind of traffic events coverage and duration of detecting based on coil according to claim 1 determined method, it is characterized in that, the incident duration t described in step 5 is,

t＝(L _i-|ω _si|*Δt-S _i+|ω _bi|*Δt)/(|ω _bi|-|ω _si|)

In formula, S _ifor starting ripple, last catch up with the queue clearance length in parking ripple direction, ω _bifor the startup wave-wave speed of this entrance driveway, L _ifor this entrance driveway queue length, ω _sjparking wave-wave speed for this entrance driveway.

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