IMPROVEMENT IN THE QUALITY CONTROL METHOD TO DISTINGUISH THE BLACK SPOTS OF THE ROAD

Transcription

1 IMPROVEMENT IN THE QUALITY CONTROL METHOD TO DISTINGUISH THE BLACK SPOTS OF THE ROAD Yulong PEI Professor Transporaion Research Deparmen Harin Insiue of Technology P.O. Box 2526, Harin Insiue of Technology, Haihe Road 202, Nangang Disric, Harin, Heilongjiang , P. R. China Fax: Jianmei DING Associae Professor School of Mechanical and Elecrical Engineering Harin Insiue of Technology P.O. Box 2503, Haihe Road 202, Nangang Disric, Harin, Heilongjiang , P. R. China Fax: Asrac: I shows several differeniaing mehods in his paper and he qualiy conrol mehod is improved. The qualiy conrol mehod is used o differeniae he Black Spos in he same condiion of he road and he raffic. When applying he mehod o pracice, i assumes ha he proailiy of he raffic acciden oeys he Piosson disriuion, hen a mahemaic formula is se up. Bu he sa characer of he acciden frequency µ which akes record is no analyzed, his makes precision of he resul decrease in he mehod. Some lieraure are consuled, and i akes n and 1 / as he parameers of he Gamma disriuion o compue he equal acciden rae λ, which makes λ raional and he resul exac.a las, i akes he example of Shen-Da expressway o analyze he Black Spos y he mehod and achieve he raional resul. Key Words : Acciden rae, Black Spo, Qualiy conrol mehod 1. INTRODUCTIN The field where he road raffic acciden ofen occurs is called Black Spo, is he secions of road or inersecions where he road raffic acciden is ousanding more han oher secions and inersecions. I is he firs and a pivoal sep for improving he road safey level o confirm he secions of road or inersecions ha need improving he road safey level place, disinguish ligh and weigh and ake he good measure o improve he road safey level effecively. Black spos adly decreases he road serve qualiy, and here is characerisic ha he proporion of he acciden numer accouns for he oal numer is high. So i is economy and effecive mehod for improving he road raffic safey condiion o differeniae he lack spos, analyse he cause of lack spos and raise he comforale measure. Especially when he fund is lack, i is advisale o firsly improve he road safey level. 2106

2 2. DISCUSSING IDENTIFICATION METHODS There are several mehods o idenify Black spos in or ou of china, as follows: 2.1 Acciden Frequency Mehod This mehod is ha aking an acciden numer as idenificaion crierion, if he acciden numer of idenified secion is more han he crierion, he secion is regarded as Black spos. I is good for he mehod o choose, calculae and e clear a a glance. Bu shorcoming is ha i is difficul o idenify he Black spos when his acciden numer is as much as ha, ha is ecause he difference of road condiion and raffic condiion is no aken ino accoun in he mehod. I may resul in hinking nohing of Balck spos as Balck spos. So i is he conclusion ha he mehod is suiale for he secion and inersecion of mini-scope. 2.2 Acciden Rae Mehod Afer 1940, he developed counry develops he raffic survey. When idenifying Black spos, he acciden rae mehod is advanced ecause of holding he grea of raffic numer daa. This mehod akes he acciden numer of million moor-kilomeer of one year as idenificaion crierion in secion, million moor in inersecion. So when he acciden rae exceeds he crierion, he field is regarded as Block spos. This mehod is eer han acciden frequency mehod, u i is wo shorcomings for he mehod, one is ha acciden rae value is high in he secion where raffic numer value and acciden numer value is low, anoher is ha acciden rae value is low in he secion where raffic numer value and acciden numer value are high. So when aking use of his mehod o idenify, i may make idenifying resul inaccurae. 2.3 Marix Mehod This mehod akes acciden numer and acciden rae as he crierion, he level axis denoes acciden numer, uprigh axis presens acciden rae. One marix cell expresses one secion of road. The marix cell value shows he degree of risk of secion. The riskies secion has he highes acciden numer and acciden rae in down righ corner of he marix. I is meri for mehod o hink over he acciden numer and acciden rae, u here are some shorcomings. I can show he degree of risk of secion, u can no disinguish hese secions in which acciden numer is low and acciden rae is high or acciden numer is high and acciden rae is low, only o regard hem as nohing of Black spos and can consider he crierion and severiy of acciden. 2.4 Toal Equivalen Acciden Numer Mehod If he value of acciden numer, severiy of which is differen, simply calculaes, i resuls in ha he idenifying resul is inaccurae. For example, he numer value of wo secions is he same, u he deah numer value of one is higher han anoher. Apparenly, he faalness in he secion where he deah numer value is high is higher. To idenify Black spos correcly, 2107

3 aking ino accoun he severiy of he acciden, he oal Equivalen acciden numer mehod is developed (Pei, This mehod calculaes he degree of severiy of acciden hrough calculaing modulus of injured numer and deah numer. Because of lack of hinking over raffic numer and he lengh of secion, i is he same shorcoming as acciden rae mehod and he modulus have grea influence on he idenifying resul. 2.5 Qualiy Conrol Mehod In 1956, he people such as Norden, develops qualiy conrol mehod which is differen from ohers. firsly, on he assumpion ha he acciden numer in secion sumis o he Piosson disriuion, hen compare he acciden rae wih he equal acciden rae in he similar secion. According o noailiy, he highes value and he lowes value of synhesis acciden rae are ascerained in Black spos. If he acciden rae is higher han he highes, he secion is hough of as Black spos. In fac, qualiy conrol mehod is one ha ases on hypohesis. I is shown ha he mehod is eer han ohers when applied, u he precedence order ha Black spos is reconsruced is no fixed and he severiy of acciden is no considered. 2.6 Criical Rae Mehod In 1997, J. S. CHEN and S. C. WANG summarize he meri and shorcoming of mehods aove o develop Criical rae mehod. In his mehod, he acciden rae which he user of road can sand is regarded as criical rae. According o noailiy, here is differen lowes value of acciden rae corresponding o differen criical rae. When he acciden rae of one secion is across criical rae, he secion is hough of as Black spos. Thinks o considering he characers of Black spos, he mehod is eer han mehods aove, and can fix he order ha he Black spos is reconsruced hough choosing differen criical rae. Bu he criical rae is changing wih economy developmen and sandard of living improvemen, so he daa should e updaed o make sure he criical rae ased on raffic acciden and uilding fund (Jodi, C. e al., From he analysis of several mehods aove, alhough he several mehods idenify Black spos from differen way, some condiions, such as raffic volume, road condiion or severiy of acciden, can e ignored, his makes veraciy of idenificaion resul reduce. Therefore, each mehod should e applied in comforale condiion. When idenifying Black spos, i is supposed o ake ino accoun hese condiion o sudy he mehod o make he resul exac (Sean, T. D. e al., QUALITY CONTROL METHOD The mehod o idenify Black spos has each meri. Alhough here are some shorcomings for hem, which is limied y applicaion condiion, u he mehod is chosen asing on he road condiion. The qualiy conrol mehod is used o idenify Black spos in he road which have he same road condiion and raffic condiion (Hiroshi,

4 When applying he qualiy conrol mehod, firsly i is assumed ha proailiy of raffic acciden happening oeys Piosson disriuion in any condiion, i.e. proailiy of n raffic accidens happening can e denoed y formula (1 in ime. µ e n P( n µ, = ( µ ( n 0 n! (1 where, µ denoes acciden frequency of road secion [4]. Mean and variance of n are as follows: E ( n = µ, Var ( n = µ (2 If confidence level of he disriuion is made 95%, upper limi value + R is as follows: R + 1 = λ λ + i = 1, 2, KKn (3 m i 2m i Where, λ is average acciden rae of a hundred million vehicle in similar secions (ime /a hundred million vehicle, m i oal vehicle numer in i secion (a hundred million vehicle. E ( n λ = (4 m i When comparing acciden rae of a hundred million vehicle wih his secion is regarded as Black spos. R +, if i is higher han + R, 4. IMPROVING METHOD In he qualiy conrol mehod, as saisical feaure of acciden frequency is no considered, u akes record value., i makes veraciy of he resul decrease. In his paper, some documen is consuled, Gamma disriuion in which formal parameer is used o express densiy funcion, as follows: e p( µ = µ µ Γ( n n 1 n ( µ > 0 The mean and variance of he disriuion are as follows: n and rule parameer is 1 / is (5 µ = n /, σ = n / = µ / n ( The parameer n and is calculaed, as follows: n 2 2 / σ = µ, 2 / σ The mean and variance ge from he mean and variance of sample. = µ (7 So, when he acciden frequency µ oeys p (µ disriuion, he oundary disriuion of 2109

5 acciden ime is as follows: n n Γ( n + n P( n, p( µ d = ( n+ n n! Γ( n ( + P ( n = µ µ (8 µ The mean and variance is as follow: n n 2 2 E( n = = µ, Var( n = (1 + = µ + σ (9 So, he average rae λ may e aken place y formula(10. E ( n λ = (10 m i Afer finishing idenifying Black spos y qualiy conrol mehod improved, acciden rae of a hundred million vehicle is arranged y he order from high o low. I is firs o improve he secion ha has high acciden rae (Dinesh, APPLICATION There were one housand and four raffic accidens from January, 1994 o June,1995. As he raffic and road condiion of secion along Shen-Da freeway, qualiy conrol mehod is used o idenify Black spos. Through comparing wih he acciden rae calculaed. 35 Black spos have een confirmed, and he order of secion improved have een confirmed according o acciden rae. According o raffic daa and acciden daa, Shen-Da freeway is divided ino weny four inervals In each inerval acciden rae of a hundred million vehicle is shown in ale 1.There is plain from one inerval o seveny inerval, where road design indexes are he same. Average acciden rae of a hundred million vehicle is There is a mounainous area from eigheen inerval o weny four inerval, Average acciden rae of a hundred million vehicle is Taking confidence of Piosson 95%, ale 1 presens upper limi R + of every inerval According o raffic acciden disriuion along Shen-Da freeway, i is divided ino hree hundred seveny six secions, here are hiry five secions in which acciden rae is higher han upper limi (Tale 2, which are Black spos. acciden rae of a hundred million vehicle is arranged y he order from high o low. I is firs o improve he secion ha has high acciden rae (Mohammed, M.S. e al., CONCLUSION In he qualiy conrol mehod, as saisical feaure of acciden frequency is no considered, u akes record value., i makes veraciy of he resul decrease. So, qualiy conrol mehod is improved in paper. On he assumpion ha acciden frequency oeys Gamma disriuion and proailiy of acciden happening oeys Piosson disriuion, qualiy conrol mehod is developed. i akes he example of Shen-Da expressway o analyze he Black Spos y he 2110

6 mehod and achieve he raional resul. This improved mehod may e used o idenify Black spos as an avail mehod. Tale 1. Space Locaion, Toal Vehicle Numer and Traffic Acciden Indexes Numer Inerval Mileage mark Inerval lengh (km Toal raffic (a hundred million vehicle Acciden ime Acciden rae of a hundred million vehicle (ime/ a hundred million vehicle Upper limi (ime/ a hundred million vehicle 01 Originaion~ sujaun k0~k Sujiaun~shilihe k19+982~ k Shilihe~denga k35+350~ k Denga~ k45+888~ Xiawangzhuang k Xiawangzhuang~ k62+954~ changuang k Changuang~ k68+107~ Dadaoying k Dadaoying~ k91+561~ Tengao k Tengao~Dayu k ~ k Dayu~Xiliu k ~ k Xiliu~Huzhuang k ~ k Huzhuang~ k ~ Xingda k Yingda~Yinggai k ~ k Yinggai~ k ~ Tuanshanzi k Tuanshanzi~ k ~

7 Shagangzi k Shagangzi~ k ~ Mianyuquan k Mianyuquan~ k ~ Xongyue k Xongyue~Liguan k ~ k Lliguan~Iuun k ~ k Iuun~Naun k ~ k Naun~Xiaojialu k ~ k Xiaojialu~ k ~ Zhuangshanou k Zhuangshanou~ k ~ Sanshilipu k Sanshilipu~ k ~ Jjinzhou k Jinzhou~houyan k ~ k Tale 2. The Moraliy Rae of Ten Thousand Vehicle of Black Spo and Reuilding Order Numer Mileage mark of Acciden Numer Mileage mark of acciden 01 K161~K K ~K K363~K K348~K K ~K K4~K K173~K K79+500~K K284~K K64~K K317~K K358+K K ~K K179~K K68~K K10~K K200~K K ~K K322~K K138~K K ~K K145+K K14+800~K K114+K K19+500~K K122+K K ~K K32~K K257~K K35~K K263+K K203~K K ~K K71~K K ~K

8 REFERENCE Dinesh M. (1999 Road accidens in India[J], The Inernaional Associaion of Traffic and Safey Science Rresearch, Vol.23, No.1, Hiroshi K. (1997 Road Accidens in Japan[J], The Inernaional Associaion of Traffic and Safey Science Rresearch, Vol.21, No.2, Jodi C. and Fred M. (2001 The Effec of Ice Warning Signs on Ice~acciden Frequencies and Severiies, Acciden Analysis & Prevenion,Vol.33, 99~109. Joksch, H. C. (1993 Velociy change and he faaliy risk in a crash a rule of hum[j], Acciden Analysis and Prevenion, Vol.25, No.1, Mohammed, M.S., and Masud M. (1999 Road accidens in meropolian Dhaka, Bangladesh[J], IATSS Research, Vol.23, No.2, Pei Y. (2002 Road raffic acciden cause analysis and precauion measure research, Nanking: Souheas Universiy. Sean T.D., Lisa A.H. and Jill S. (2000 Commuer cyclis acciden paerns in orono and Oawa [J], Journal of Transporaion Engineering, Vol.21, No.1,