America Joural of Traffic ad Trasporaio Egieerig 207; 2(3): 32-38 hp://www.sciecepublishiggroup.com/j/aje doi: 0.648/j.aje.2070203.2 Research o Bus Prioriy Corol o No-coordiaed Phase Based o Trasmodeler A Case Sudy of Chagjiag Road i Huagdao Disric of Qigdao Zhag Juyou, Liao Yapig * College of Trasporaio, Shadog Uiversiy of Sciece ad Techology, Qigdao, Chia Email address: juyouzhag@sdus.edu.c (Zhag Juyou), liaoyapigsk@63.com (Liao Yapig) * Correspodig auhor To cie his aricle: Zhag Juyou, Liao Yapig. Research o Bus Prioriy Corol o No-coordiaed Phase Based o Trasmodeler A Case Sudy of Chagjiag Road i Huagdao Disric of Qigdao. America Joural of Traffic ad Trasporaio Egieerig. Vol. 2, No. 3, 207, pp. 32-38. doi: 0.648/j.aje.2070203.2 Received: Jue 26, 207; Acceped: July, 207; Published: Augus, 207 Absrac: May sudies focus oly o he bus prioriy reques o coordiaed- phase i raffic sigal coordiaio of arery, while igorig he bus prioriy corol o o-coordiaed phases. For he o-coordiaed phases wih more bus raffic, i is ecessary o achieve bus prioriy corol o o-coordiaed phases. Based o he coordiaed corol o arery ad bus prioriy corol o he coordiaed phase, his paper pu forward he corol priciple of bus prioriy o he o-coordiaed phases for acive early urig o ad laely breakig gree ligh ad he calculaio mehod of he gree ime o each phase wih he limiaio of upper ad lower limis of he gree bel ad he miimum gree ime of every phase. This paper ook he Chagjiag Road i Huagdao Disric of Qigdao as a example, ad esablished he exisig sigal corol scheme of Chagjiag Road i Trasmodeler. Afer ha, we ipu bus prioriy corol priciple o he o-coordiaed phases ad algorihm pu forward i his paper io he simulaio sofware sysem. The, wo raffic flow codiios were respecively simulaed before ad afer implemeig bus prioriy o he o-coordiaed phases of he raffic sigal o he Chagjiag Road. Fially, he oupu evaluaio idex of each iersecio sigal o wo codiios were compared ad aalyzed. The resuls showed ha he proposed corol priciple ad algorihm could reduce he raffic delay ad improve he efficiecy of road operaio effecively. Keywords: No-coordiaed Phase, Bus Prioriy, ree Ligh, Mode, Trasmodeler. Iroducio Now mos of aioal ciies are implemeig sigals coordiaed corol o urba arery, i which he sigal coordiaed corol o urba arery is o make all he sigals o he mai lie corol for joi, o achieve gree bel, so ha reducig he frequecy of ecouerig red ligh while he vehicles are ruig a a se speed, ad achievig he purpose of opeig he mai road []. ree bel badwidh ad sigal phase differece o he mai road are opimized by he social raffic deeced hrough he deecor. The coordiaed corol o he mai road may be udermied if he bus prioriy corol sraegies are implemeed simulaeously. Therefore, i is of grea pracical sigificace o realize he bus prioriy o iersecios wihou damagig sigal coordiaed corol sysem o he mai road. I he field of implemeig bus prioriy o sigal coordiaed corol, may scholars have doe a lo of research. Yag Xiaoguag e al. [2] used he liear programmig model o propose a mehod o deermie he bus prioriy sigal wih he overall bes efficiecy of he sysem uder fixed cycle codiios, ad o make a case sudy, however oly he firs phase was assumed i his sudy ha here were buses o hrough, here were o explaaios o how o deermie he bus prioriy applicaio of oher phases, he imig did o cosider pedesria phase wih may limiaio. Zhag Weihua e al. [3] proposed o ake he miimum per capia delay as he opimize arge for he sigal cycle, ad he spli was deermied by passeger raio of phase ad he phase sauraio. The case aalysis showed ha make imig accordig o he miimum oal delay could reduce per capia delays hough icreasig average delay. Nicholas E. Lowes [4] esablished per capia delay model o he mai lie, assumed ha he ravel ime of each ravel mode was equal,
33 Zhag Juyou ad Liao Yapig: Research o Bus Prioriy Corol o No-coordiaed Phase Based o Trasmodeler A Case Sudy of Chagjiag Road i Huagdao Disric of Qigdao ad aalyzed he raffic beefi chage of implemeig bus prioriy uder he mai lie. Ma Wajig e al. [5] aimed a he miimum impac of social raffic ad pu forward a bus prioriy corol model o he mai road o esure ha he egaive impac of social raffic was miimal ad could reduce he bus delay. Wag Diahai e al. [6] had did he bus prioriy corol research o coordiaed phase accordig o he bus prioriy ad coordiaio prioriies of arerial gree wave. Li Zhelog e al. [7], akig he ifluece of he bus prioriy corol sraegy a he upsream iersecio o coordiaed corol of he gree wave ad he dowsream iersecio io accou, pu forward a bus prioriy model o he mai road cosiderig he delay of he upsream ad dowsream iersecios. I he disribued iellige corol, Fracois Dio [8-9] proposed a opimizaio algorihm wih miimum weighed delay ad parkig imes, ad esablished he coversio rules of coordiaig he upsream ad dowsream vehicles, ad assiged differe prioriy weighs accordig o he prioriy levels. Alexader [0] adoped codiioal public raspor sraegy uder he coordiaed corol o he mai road o deermie wheher he bus wih prioriy reques was lae, oly he lae bus could be corolled for prioriy, he used he large ime headway appeared he ed of phases o provide sigal corol for he bus wih he cosrais of upper ad lower limis of he gree bad. Yu Hoghog [], akig he per capia delay as he corol arge, he remaiig road space as he dyamic cosrai, cosruced bus sigal prioriy coordiaed-corol model o he muli-iersecio usig VISSIM sofware by he example. Xue Chagsog e al. [2] ook he Logpa middle Road of Najig as a example, ad sudied he feasibiliy ad effeciveess of bus sigal prioriy corol mehod uder he coordiaed corol hrough he comparaive aalysis of he road raffic uder he five differe sigal corol sraegies. The commo pois of above bus prioriy research o he coordiaed corol of he mai lie are ha hey all sudy he bus prioriy of he coordiaed phase uder he coordiaed corol o he mai lie, ad here is lile research o bus prioriy of he o-coordiaed phases, which dose o applicable for he mai roads wih more buses o o-coordiaed phases ha ha o coordiaed phase ad cao make improveme o heir raffic efficiecy, so oly implemeig bus prioriy o he coordiaed phase does o accord wih he characerisics of may bus lies i Chia. Therefore, referrig he research a home ad abroad, his paper proposes a bus prioriy corol sraegy o o-coordiaed phase based o coordiaed corol of he mai lie ad he calculaio mehod of gree ime of each phase afer implemeig bus prioriy, ad akes he Chagjiag Road bus lie sysem i Huagdao Disric of Qigdao as he sudyig case. Fially, based o he Trasmodeler sofware, we compare he oal delays, he average delay, he per capia delay ad he oal umber of sops a he iersecio of he mai roads afer implemeig he above proposed mehod wih ha before implemeig his mehod, ad he make he coclusio aalysis. 2. Research Ideas The o-coordiaed phase bus sigal prioriy layer is added o he ruk sigal which has achieved he sigal coordiaio level. The core module of his layer is he mode of early-sarig gree ligh ad mode of laely breakig gree ligh. Two modes of bus prioriy should be based o he premise of o desroyig he coordiaio of he mai road. Whe he bus issues a bus prioriy reques, ad he reques phase is he curre release phase, if he bus arrived a he parkig lie of he iersecio a he gree ime, he sysem will keep he sigal uchaged, if o, he ope he mode of laely breakig he gree ligh, ad compress gree ime of oher phases, so as o provide he maximum available exeded gree ime for he bus prioriy; Whe he reques phase is o he curre release phase, if he curre phase has reached is shores gree ime, he he mode of early ope gree ligh o immediaely cu off he phase, ad compress he gree ime of o-coordiaed phases locaed behid his phase ad before he coordiaed phase; If he curre phase does o reach is shores gree ime, compress he gree ime of he oher o-coordiaed phases locaed behid he curre phase ad before he coordiaed phase uil he curre phase reaches he miimum gree ime, ad provide he maximum advace opeig gree ime for he bus prioriy whe he precodiio is me. The corol flow of bus sigal prioriy layer o he o-coordiaed phases is show i Figure. below. 2.. Mode of Laely Breakig ree Ligh 2... Deermie he Available Exeded ree Time o he No-coordiaed Phase Accordig o he posiios of o-coordiaed phasel wih he bus prioriy reques ad he coordiaed phaseh, i ca be divided io wo cases o deermie he maximum available exeded ime provided for he o-coordiaed phase l : () Whe l < h, ha is, i he h cycle, whe he o-coordiaed phasel wih he bus prioriy reques is i fro of he coordiaed phaseh, o compress he gree ime of phases from he phase l + o he coordiaed phaseh, he he calculaio mehod of he maximum available exeded gree ime provided for he o-coordiaed phasel is: h = gxi + l + Where: : The maximum exeded gree ime ca be provided o he o-coordiaed phase wih he bus prioriy reques i he h cycle; gxi gxh () : The available compressed ime of he o-coordiaed phasei i he h cycle, s; gxh : The differece bewee he lower ime eh of he gree wave ad he sar ime sh o he coordiaed phase h i he h cycle, which ca be calculaed by he followig formula:
America Joural of Traffic ad Trasporaio Egieerig 207; 2(3): 32-38 34 gxh = (2) Assume ha he exeded gree ime required for bus prioriy reques is gb, if gb, he imig of he eh sh o-coordiaed phase wih he bus prioriy reques is uchaged, oherwise, he mode of laely break gree ligh is adoped. Figure. The corol flow char of Implemeig bus prioriy o he o-coordiaed phases. (2) Whe l > h, ha is, i he h cycle, whe he o-coordiaed phase l wih he bus prioriy reques is behid he coordiaed phaseh. The all he available compressed gree ime of he o-coordiaed phases behid he phase l i he h cycle, he o-coordiaed phases i fro of he phase h i he + cycle ad he coordiaed phase h i he +h cycle are used o provide exeded gree ime for o-coordiaed phase l wih a bus prioriy reques i he h cycle. The calculaio mehod is: Where: k gxi l + h + gxi + = + + gxh (3) + gxi : The available compressed gree ime of he o-coordiaed phasei i he +h cycle, s; + gxh : The available compressed gree ime of he coordiaed phase h i he +h cycle, s. Assume ha he exeded gree ime required for bus prioriy reques is, if gb gb, he imig of he o-coordiaed phase wih he bus prioriy reques is uchaged, oherwise, he mode of laely break gree ligh is adoped. 2..2. Deermie he ree Phase of Each Phase Afer Implemeig he Bus Prioriy o No-coordiaed Phase () The gree ime of he o-coordiaed phase wih a bus prioriy reques I he mode of laely break gree ligh, he gree ime of he o-coordiaed phase wih a bus prioriy reques is he sum of he origial gree ime exeded gree ime. Tha is: gl ad he gl = + (4) (2) The gree ime gbi of oher compressed o-coordiaed phases Use he equal flow raio o share he oal compressed
35 Zhag Juyou ad Liao Yapig: Research o Bus Prioriy Corol o No-coordiaed Phase Based o Trasmodeler A Case Sudy of Chagjiag Road i Huagdao Disric of Qigdao gree ime o calculae he gree ime compressed o-coordiaed phases. Tha is: mi gbi = max gbi mi, gbi of oher yi, gi (5) Y Where: gbi, : The shores gree ime ha mus be maiaied for he o-coordiaed phase i of he h cycle. (3) Deermie he gree ime of he coordiaio phase I order o esure ha he gree bel is o damaged, ad he compressed coordiaed phase h is compesaed for he gree ligh, we eed o backward he coordiaed phase for his compesaio ime ghc. The he compesaio ime is: ghc h gxi i+ = (6) 2.2. Mode of Early Turig o ree Ligh ghc 2.2.. Deermie he Available Advaced Sar Time of ree Ligh ha Oher Phases Ca Be Provided for he No-coordiaed Phase l wih a Bus Prioriy Reques Whe he o-coordiaed phase l wih he bus prioriy is riggered, ad he bus arrives a he sop lie a he ime of he o-coordiaed phase o, accordig o wheher he phase o has fiished he miimum gree ime, deermiig he available advaced sar ime ca be divided io he followig wo cases (We ake he siuaio ha he coordiaio phase h is i fro of he o-coordiaed phase o ad l as a example o discuss. Oher siuaios' sudy ideas are similar o his siuaio, such as he siuaio ha he coordiaed phase h is bewee he o-coordiaed phase o ad l, ad he siuaio ha he coordiaed phaseh is behid he o-coordiaed phase o ad l ): () Whe he phase o does o fiish he miimum gree ime, if l < o, he he available advaced sar ime of gree ligh ha oher phases ca be provided for he o-coordiaed phase l wih a bus prioriy reques ca be calculaed by: gyl k h l - + + + + mi( + +, g g ) (7) = gyi o gyi gyi h+ Where: : he available advaced sar ime of gree gyl ligh ha oher phases ca be provided for he o-coordiaed phase l wih a bus prioriy reques i he h cycle, s; : he available advaced sar ime of gree + gyi ligh ha he o-coordiaed phase i ca be provided for he o-coordiaed phase l wih a bus prioriy reques i he +h cycle, s; g : The edig mome of he gree + he ligh o he coordiaed phaseh i he +h cycle, s; he hm + g he : The upper limi mome of he gree bel o coordiaed phase h i he +h cycle, s. If l > o, he he available advaced sar ime of gree ligh ha oher phases ca be provided for he o-coordiaed phase l wih a bus prioriy reques ca be calculaed by: l k h, gyl o l + + + + = mi( gyi + gyi + gyi ghe ghm ) (8) Where is symbolic meaigs are he same as he above formula. (2) Whe he phase o has fiished he miimum gree ime, he available advaced sar ime of gree ligh ha oher phases ca be provided for he o-coordiaed phase l wih a bus prioriy reques ca be deermied by he followig formula: If l < o, he k h l + + + + = + gyi + gyl o gyi + gyi he hm o2 0 + h+ (9) mi(, g g ) If l > o, he l k h, gyl o o o + l + 2 + + + = mi( + gyi + gyi + gyi ghe ghm ) (0) I he formula (9) ad (0): o he phase o i he h cycle, s; o : The origial gree ime o : The gree ime 2 has ra by he phase o afer i urig off he gree ligh, s. Ad oher symbolic meaigs have bee described above. 2.2.2. Deermie of he ree Time of Oher Phases () Deermie he gree ime of oher o-coordiaed phases Similar o he mode of laely breakig gree ligh, he o-coordiaed phases uses equal flow raio o share he compressio ime, he calculaio mehod is: Where: gsi yi = max( gimi, gi ) () gsl Y + gsi : The gree ime of phasei i he h cycle, s; : The advaced sar ime of gree ligh o he gsl o-coordiaed phase wih he bus prioriy reques i he h cycle, s. 3. Simulaio Research o Bus Prioriy of No-coordiaed Phase of Chagjiag Road i Huagdao Disric 3.. Premise Assumpios o he Mai Road () The mai road is equipped wih bus prioriy sysem, icludig bus prioriy reques sysem, commuicaio sysem
America Joural of Traffic ad Trasporaio Egieerig 207; 2(3): 32-38 36 ad raffic sigal corol sysem, ad has implemeed he sigal coordiaio corol ad bus prioriy sigal corol o he coordiaed phase; (2) The mai road icludes bus laes ad special erace road for public rasporaio; 3.2. The Bus Lie Sysem of Chagjiag Road Chagjiag Road area of Huagdao Developme Zoe is desely populaed wih a bloomig erriory, ad he roads i he area are equipped wih bus laes ad special erace road for public rasporaio. The bus lies are dese, icludig 6, 9, 8, 22, 28, 3 ad 80 bus, he layou of each lie as show below i Figure.3, he yellow area i he Figure.3 o behalf of he cosrucio secio. I addiio, five sigaled iersecios of he mai road, icludig he iersecios respecively culivaed by Chagjiag Road wih Jiagsha Road, Lusha Road, Jiggagsha Road, Wuyisha Road ad Alisha Road, have bee implemeed he sigal likage corol. Huagdao have bee implemeed he sigal coordiaed corol o he road ad bus prioriy corol o he coordiaed phase i he previous few years, so his aricle seleced he Chagjiag Road as a research objec o research o he bus prioriy simulaio o he o-coordiaed phase 3.3. Bus Prioriy Simulaio Evirome o Trasmodeler ) Trasmodeler sofware is a muli-fucio raffic simulaio package developed by he Uied Saes Caliper compay for urba raffic plaig ad simulaio. The specific flow of he bus prioriy simulaio o he o-coordiaed phase of he Chagjiag Road by Trasmodeler is show i he Figure.2. The disace bewee he five iersecios of he gree bel is 350m, 270m, 450m, 245m respecively, he loss ime of he gree ligh for each phase is 4s, he commo cycle of he sigal is 94s, he velociy of he gree bad is 47.5Km/h, ad he wo direcios of he badwidh is 25s, ad he direcio of he Chagjiag Road is he direcio of coordiaed phase. The bus flow deecor is se i he impor of he iersecio before he sop lie 80m. Ad he bus prioriy corol o he coordiaed phase also icludes wo corol modes of laely breakig gree ligh ad early urig o gree ligh. The lae sauraio rae se i he Trasmodeler is 2000pcu/h, he average passeger loaded by bus is 30 people ad by car is.5 people, he coversio rae of bus is 2 o he sadard car. The curre basic flow of iersecios i he Chagjiag Road is capured by he video device ad acquired by algorihm. I order o verify ad evaluae he beefi of implemeig bus prioriy o he o-coordiaed phase of he mai road sigal, his paper selecs he per capia delay, he oal delay, he average delay ad he oal parkig umber oupu by Trasmodeler as he evaluaio idex. Figure 3. The layou of each bus lie of Chagjiag Road i Huagdao. Figure 2. The specific flow of he bus prioriy simulaio o he o-coordiaed phase of he Chagjiag Road by Trasmodeler. Ad i order o alleviae he raffic cogesio i he peak of Chagjiag Road, he raffic goverme deparmes of 2) I he Trasmodeler, he raffic codiios of Chagjiag Road before ad afer implemeig bus prioriy o he o-coordiaed phase are respecively simulaed for hour. The, all he evaluaio idex daa of each iersecio oupu from he sofware afer simulaig are aalyzed ad compared, as show i Table ad Table 2 below:
37 Zhag Juyou ad Liao Yapig: Research o Bus Prioriy Corol o No-coordiaed Phase Based o Trasmodeler A Case Sudy of Chagjiag Road i Huagdao Disric of Qigdao Table. Simulaio resuls of each evaluaio idex o five iersecios. The simulaio resuls before implemeig bus The simulaio resuls afer implemeig bus prioriy Iersecio prioriy o he o-coordiaed phase o he o-coordiaed phase Per capia The oal he average he oal parkig Per capia The oal he average he oal parkig delay delay delay umber delay delay delay umber Chagjiag Road-Jiagsha Road 54.9 7776 56.9 020 44.9 73800 55.2 0 Chagjiag Road-Lusha Road 56.8 49650 45. 790 46.9 49330 40 773 Chagjiag Road-Jiggagsha Road 65.7 20420 52.3 2800 59. 83240 46.9 2848 Chagjiag Road-Wuyisha Road 77. 8820 43.5 70 69.8 86760 39.6 064 Chagjiag Road-Alisha Road 88.7 84250 37.4 520 78 8280 36.7 467 Table 2. The beefi evaluaio form of implemeig bus prioriy o o-coordiaed phase. Iersecio Per capia delay The oal delay he average delay he oal parkig umber Chagjiag Road-Jiagsha Road 8.2% 5.09% 2.99% 0.88% Chagjiag Road-Lusha Road 7.43% 0.64%.3% 2.5% Chagjiag Road-Jiggagsha Road 0.05% 0.23% 0.33% -.7% Chagjiag Road-Wuyisha Road 9.47%.64% 8.97% 9.06% Chagjiag Road-Alisha Road 2.06%.7%.87% 3.49% From he above wo ables, we ca see ha afer implemeig he he bus prioriy sraegy o o-coordiaed phase of Chagjiag Road coordiaio sigal, he above-meioed evaluaio idicaors have bee grealy reduced, such as he per capia delay of Chagjiag Road - Jiagsha Road iersecio was dow o 44.9s from he origial 54.9s for8.2%, he average delay dow o 55.2s from he origial 56.9s for 2.99%, he oal parkig delay dow o 0s from022s for 0.88%, he oal delay dow o 73800s from he origial 7776s for 5.09%. Ad he various evaluaio idicaors of he oher four iersecios also had basically large or small reducio. I ca be see ha he implemeaio of bus prioriy o o-coordiaed phase is coducive o improvig he efficiecy ad he service level of road raffic. 4. Coclusio I his paper, we firs pu forward he bus prioriy algorihm for he o-coordiaed phase of he coordiaed corol o he road sigals, ad he ook he five iersecios of Chagjiag Road as he sudy case o esablish he simulaio sysem of implemeig bus prioriy o he o-coordiaed phase of Chagjiag Road sigals i Trasmodeler, ipuig parameers ad he corol algorihm proposed i his paper, ad he he wo raffic siuaios of before ad afer implemeig bus prioriy o o-coordiaed phase a each iersecio were simulaed respecively for hour. Afer ha, he oupu idex resuls of he wo raffic codiios were compared ad aalyzed. The resul showed ha he corol algorihm could effecively reduce he delay of he road ad improve he service level of he road. Bu his sudy is limied o use for he mai roads ha are suiable for implemeig coordiaed sigaled corol, ad wih more buses o o-coordiaed phases. Ackowledgemes This sudy was suppored by The Scieific Research Foudaio of Shadog Uiversiy of Sciece ad Techology for Recruied Tales (205RCJJ035). Refereces [] Z. Hui. Research o sigal corol mehod of bus prioriy o he mai road [D]. Jili Uiversiy, 20. [2] Y. Xiaoguag, L. Yu, M. sheg. Research o he deermiaio mehod of bus prioriy sigal o sigalized iersecio [J]. Chiese Joural of highway ad raspor, 200, (S): 03-06+0. [3] Z. Weihua, L. Huapu, S. Qi, L. Qiag. Timig opimizaio mehod for sigalized iersecio wih bus prioriy [J]. Joural of raffic ad Trasporaio Egieerig, 2004, (03): 49-53. [4] P. Mirchadai, L. Head, A. Kyazya. A approach Towards he iergraio of Bus Prioriy ad Traffic Adapive Sigal Corol [C]. Washigo D. C: Trasporaio Research Board 80 h Aual Meeig, 2000. [5] MA W, NI W, HEAND L, e al. Effecive coordiaed opimizaio model for rasi prioriy corol uder arerial progressig [J]. Trasporio Research Record: Joural of he Trasporio Research Board, D. C, 203 (2356): 7-83. [6] W. Diahai, Z. Hui, B. Yimig, W. Qiag. Coordiaio corol mehod for bus prioriy sigal o he mai road [J]. Joural of Souheas Uiversiy (Naural Sciece Ediio), 20, 04: 859-865. [7] L. Zhelog, Z. Mighao, W. Baoju, L. Peiku, Dog Wehui. The bus prioriy model o he mai road cosider he delay a he upsream ad dowsream iersecios [J]. Traffic Iformaio ad Securiy, 205, 05: 36-42. [8] F. Dio, B. Helliga. A rule-based real-ime raffic resposive sigal corol sysem wih rasi Prioriy applicaio o isolaed iersecio [J]. Trasporaio Research Par B, 2002 (36): 325-343. [9] F. Dio, B. Helliga. A Mehodology for Obaiig Sigal Coordiaio wihi A Disribued Real-Time Nework Sigal Corol Sysem wih Trasi Prioriy [J] Trasporaio Research Board 80 h Aual Meeig, Jauary7-, 200, Washigo, D. C.
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