Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Road traffic accidents have been a global concern facing all countries. Approximately 1.2 million people are killed annually as a result of traffic accidents and 50 million are injured. More than 90 percent of road fatalities occur in the developing world which has only 48 percent of the world’s registered vehicles. Beyond the problem of road fatalities, road traffic accidents result in disability and long term injury. They also cause considerable economic losses to victims and their families and damage properties and infrastructures. In South Africa, pedestrian fatalities account for about 40 percent of all road traffic accidents. Behaviour patterns of both pedestrians and motorists at pedestrian crossings are the main influential factors of pedestrian accidents. This study investigates behaviour patterns of pedestrians negotiating different types of crossing facilities in the town of Stellenbosch, in South Africa. A total number of 17 pedestrian crossings were selected for the study on the basis of their geometric and operational characteristics. Video-based observations together with on-street interviews were used to understand crossing behaviour patterns, namely pedestrian walking speed, pedestrian delay, gaze behaviour, pedestrian-vehicle conflicts, pedestrian compliance with road traffic rules and gap-acceptance behaviour. Results of the study showed that male pedestrians walk more than female pedestrians. The 15th percentile crossing speed for all pedestrians observed while crossing was found to be 1.13 m/s whereas the mean crossing speed was found to be 1.48 m/s. Demographic variables appeared to significantly influence pedestrian walking speed. Male and younger pedestrians exhibited higher walking speeds than female and older pedestrians. Pedestrian walking speed was also found to be affected by group size, encumbrance, type of pedestrian facility and distraction while walking. However, no effects of conflicts and the presence of a pedestrian refuge on pedestrian walking speed were found in this study. A mean total delay of 5.10 seconds was found in this study. Male and younger pedestrians experienced shorter delay compared to female and older pedestrians. The type of pedestrian facility and traffic signals during which pedestrians arrived at the kerb and crossed appeared to be other influential factors of pedestrian delay. With regard to gaze behaviour, an average number of head movements ranged from 2 to 5 at the kerb and from 3 to 5 while crossing. Conflicts with motorists peaked where crossing distances were longer and traffic volume was heavy. A red light violation ranging from 82 to 87 percent was observed in this study and on-street surveys indicated that beliefs and attitudes towards traffic control devices and traffic environment significantly explained pedestrians’ unsafe crossing behaviour. The calculated critical gap and critical lag ranged from 2.19 to 3.90 seconds and the effect of crossing distance on gap-acceptance emerged in this study. Possible interventions are finally suggested. / AFRIKAANSE OPSOMMING: Padongelukke is 'n wêreldwye probleem wat al die lande in die gesig staar. Ongeveer 1,2 miljoen mense sterf jaarliks as 'n gevolg van verkeersongelukke en 50 miljoen word beseer. Meer as 90 persent van padsterftes kom voor in die ontwikkelende wêreld met slegs 48 persent van die wêreld se geregistreerde voertuie. Bo en behalwe die probleem van padsterftes, het padongelukke gestremdheid en lang termyn beserings tot gevolg. Dit veroorsaak ook aansienlike ekonomiese verliese vir die slagoffers en hul gesinne en skade aan eiendomme en infrastruktuur. In Suid-Afrika is voetgangersterftes verantwoordelik vir sowat 40% van alle padongelukke. Gedragspatrone van beide voetgangers en motoriste by voetoorgange is die belangrikste bepalende faktore van voetganger-ongelukke. Hierdie studie ondersoek gedragspatrone van voetgangers by verskillende tipes kruisings in die dorp van Stellenbosch Suid-Afrika. ʼn Totale aantal van 17 voetoorgange is gekies vir die studie op die basis van hul geometriese en operasionele eienskappe. Video-gebaseerde waarnemings saam met op-straat onderhoude is gebruik om kruising-gedragspatrone, naamlik voetganger stapspoed, voetganger vertraging, kyk gedrag, voetganger-voertuig konflikte, voetganger nakoming van padverkeersreëls en gaping-aanvaarding gedrag te verstaan. Resultate van die studie het getoon dat manlike voetgangers vinniger loop as vroulike voetgangers. Die 15de persentiel kruising spoed vir alle voetgangers waargeneem binne kruisings was 1,13 m/s, terwyl die gemiddelde kruising spoed 1,48 m/s is. Demografiese veranderlikes beïnvloed voetgangers loop-spoed. Manlik en jonger voetgangers loop vinniger as vroulike en ouer voetgangers. Voetgangers loop-spoed word ook geraak deur die grootte van die groep, die dra van items, die tipe voetganger-fasiliteit en afleiding terwyl geloop word. Daar is egter geen gevolge van konflikte op voetgangers loop-spoed in hierdie studie gevind nie. 'n Gemiddelde totale vertraging van 5,10 sekondes is in hierdie studie gevind. Manlik en jonger voetgangers ervaar korter vertraging in vergelyking met die vroulike en ouer voetgangers. Die tipe voetgangerfasiliteit en verkeerseine was ander invloedryke faktore van voetganger vertraging. Vir waarneming van die verkeer is gevind dat die gemiddelde aantal kopbewegings gewissel het van 2 tot 5 teen die randsteen en van 3 tot 5, tydens die kruising. Konflikte met motoriste het ʼn hoogtepunt bereik waar kruising afstande langer en verkeersvolume hoër was. Rooi lig oortredings wat wissel van 82 tot 87 persent is in hierdie studie waargeneem en op-straat opnames het aangedui dat houdings teenoor verkeer-beheer toestelle en die verkeersomgewing die voetgangers se onveilige kruising-gedrag verduidelik. Die berekende kritiese gaping het gewissel van 2,19 tot 3,90 sekondes en die effek van die kruisinglengte op gaping-aanvaarding het in hierdie studie na vore gekom. Moontlike intervensies word voorgestel.

This effort seeks to answer the question; can a transferable model be developed from easily obtainable, publicly available land-use, census, roadway, and network data for the use in safety performance functions? 474 stop-controlled minor legs were used as the training data set using ordinary least squares regression. A best-fit model of maximum independent variables, n=12 was chosen using an exhaustive approach using Mallow's Cp to select the model with least bias in the predictors. The results of the analysis revealed that the combination of variables from Washington, Ohio, and North Carolina did not have a strong relationship. The best-fit model incorporated functional class information of the major-leg, minor leg functional class information, longitudinal markings, access to a parking lot, and population density of census tract. Validation of the model demonstrated an average 59 percent error between the model estimated and actual AADT values for validation data set (n=54). Furthermore, separate models for each state revealed a lack of uniformity in the dependent variables, and more variance description of the state specific AADT.

At signalized intersections, pedestrians are considered to be amongst the most vulnerable. When in the crosswalk at intersections without protected left-turn phasing, pedestrians are particularly at risk from left-turning vehicles. Until recently, a wide variety of indications were in use across the US to indicate a permissive left-turn condition to the driver. In Oregon, the Flashing Yellow Arrow (FYA) has been used to indicate the permissive left-turn condition for approximately 10 years. With the addition of the FYA in the 2009 MUTCD, it is likely that its use will continue to increase nationally. Though many operational and safety issues have been studied about the FYA indication, this research proposes to fully investigate factors that influence driver behavior in the context of the permissive left-turn conflict with pedestrians. Specifically, the research seeks to study driver glance behavior to identify reasons why drivers are, "looking at but not seeing" pedestrians in or near the crosswalk or not searching for the presence of pedestrians at all. / Graduation date: 2013

published_or_final_version / Gerontology / Master / Master of Social Sciences

This thesis discusses the effect of sequential conflict resolution maneuvers of a continuous flow of agents through a finite control volume. Video analysis of real world traffic flows that exhibit self-organized capabilities is conducted to extract characteristics of those agents. A tool is created which stabilizes the input video and extracts motion from it using the background subtraction method. I discuss the tool in detail as I created it to be user friendly and easily modifiable for other uses. The aim of the video analysis I conduct is to determine characteristics of agents in self-organized traffic flow. Comparisons are made with agents under sequential conflict resolution schemes and those that exhibit these self-organized capabilities to determine if agents under sequential control can approach the behaviors of those in self-organized environment. Flow geometries are studied and generalized with the goal of determining stability characteristics of arbitrary flow geometries. Stability analysis includes analytical proof of bounds on the conflict resolution maneuvers.

A critical set in a Latin square of order n is a set of entries in an n×n array which can be embedded in precisely one Latin square of order n, with the property that if any entry of the critical set is deleted, the remaining set can be embedded in more than one Latin square of order n. The number of critical sets grows super-exponentially as the order of the Latin square increases. It is difficult to find patterns in Latin squares of small order (order 5 or less) which can be generalised in the process of creating new theorems. Thus, I have written many algorithms to find critical sets with various properties in Latin squares of order greater than 5, and to deal with other related structures. Some algorithms used in the body of the thesis are presented in Chapter 3; results which arise from the computational studies and observations of the patterns and subsequent results are presented in Chapters 4, 5, 6, 7 and 8. The cardinality of the largest critical set in any Latin square of order n is denoted by lcs(n). In 1978 Curran and van Rees proved that lcs(n)<=n²-n. In Chapter 4, it is shown that lcs(n)<=n²-3n+3. Chapter 5 provides new bounds on the maximum number of intercalates in Latin squares of orders m×2^α (m odd, α>=2) and m×2^α+1 (m odd, α>=2 and α≠3), and a new lower bound on lcs(4m). It also discusses critical sets in intercalate-rich Latin squares of orders 11 and 14. In Chapter 6 a construction is given which verifies the existence of a critical set of size n²÷ 4 + 1 when n is even and n>=6. The construction is based on the discovery of a critical set of size 17 for a Latin square of order 8. In Chapter 7 the representation of Steiner trades of volume less than or equal to nine is examined. Computational results are used to identify those trades for which the associated partial Latin square can be decomposed into six disjoint Latin interchanges. Chapter 8 focusses on critical sets in Latin squares of order at most six and extensive computational routines are used to identify all the critical sets of different sizes in these Latin squares.

A critical set in a Latin square of order n is a set of entries in an n×n array which can be embedded in precisely one Latin square of order n, with the property that if any entry of the critical set is deleted, the remaining set can be embedded in more than one Latin square of order n. The number of critical sets grows super-exponentially as the order of the Latin square increases. It is difficult to find patterns in Latin squares of small order (order 5 or less) which can be generalised in the process of creating new theorems. Thus, I have written many algorithms to find critical sets with various properties in Latin squares of order greater than 5, and to deal with other related structures. Some algorithms used in the body of the thesis are presented in Chapter 3; results which arise from the computational studies and observations of the patterns and subsequent results are presented in Chapters 4, 5, 6, 7 and 8. The cardinality of the largest critical set in any Latin square of order n is denoted by lcs(n). In 1978 Curran and van Rees proved that lcs(n)<=n²-n. In Chapter 4, it is shown that lcs(n)<=n²-3n+3. Chapter 5 provides new bounds on the maximum number of intercalates in Latin squares of orders m×2^α (m odd, α>=2) and m×2^α+1 (m odd, α>=2 and α≠3), and a new lower bound on lcs(4m). It also discusses critical sets in intercalate-rich Latin squares of orders 11 and 14. In Chapter 6 a construction is given which verifies the existence of a critical set of size n²÷ 4 + 1 when n is even and n>=6. The construction is based on the discovery of a critical set of size 17 for a Latin square of order 8. In Chapter 7 the representation of Steiner trades of volume less than or equal to nine is examined. Computational results are used to identify those trades for which the associated partial Latin square can be decomposed into six disjoint Latin interchanges. Chapter 8 focusses on critical sets in Latin squares of order at most six and extensive computational routines are used to identify all the critical sets of different sizes in these Latin squares.

A critical set in a Latin square of order n is a set of entries in an n×n array which can be embedded in precisely one Latin square of order n, with the property that if any entry of the critical set is deleted, the remaining set can be embedded in more than one Latin square of order n. The number of critical sets grows super-exponentially as the order of the Latin square increases. It is difficult to find patterns in Latin squares of small order (order 5 or less) which can be generalised in the process of creating new theorems. Thus, I have written many algorithms to find critical sets with various properties in Latin squares of order greater than 5, and to deal with other related structures. Some algorithms used in the body of the thesis are presented in Chapter 3; results which arise from the computational studies and observations of the patterns and subsequent results are presented in Chapters 4, 5, 6, 7 and 8. The cardinality of the largest critical set in any Latin square of order n is denoted by lcs(n). In 1978 Curran and van Rees proved that lcs(n)<=n²-n. In Chapter 4, it is shown that lcs(n)<=n²-3n+3. Chapter 5 provides new bounds on the maximum number of intercalates in Latin squares of orders m×2^α (m odd, α>=2) and m×2^α+1 (m odd, α>=2 and α≠3), and a new lower bound on lcs(4m). It also discusses critical sets in intercalate-rich Latin squares of orders 11 and 14. In Chapter 6 a construction is given which verifies the existence of a critical set of size n²÷ 4 + 1 when n is even and n>=6. The construction is based on the discovery of a critical set of size 17 for a Latin square of order 8. In Chapter 7 the representation of Steiner trades of volume less than or equal to nine is examined. Computational results are used to identify those trades for which the associated partial Latin square can be decomposed into six disjoint Latin interchanges. Chapter 8 focusses on critical sets in Latin squares of order at most six and extensive computational routines are used to identify all the critical sets of different sizes in these Latin squares.

In the last several years, there has been growing worldwide interest in making streets safer for all users--pedestrians, cyclists, and motorists. One approach, shared space, is a traffic calming technique as well as urban design concept. This technique strives to fully integrate the roadway into the urban fabric by removing elements such as lane markings, curbs, and traffic signs. By removing these elements and creating a more plaza-like space, these sites become ambiguous and no user group as priority. The technique is relatively new, and the majority of existing research concerns pedestrians only. This mixed methods research focused on six intersections in England with the goal of understanding how bicycle riders perceive and travel through shared space intersections. Using video observations of the six sites in three cities, three shared and three control, this project analyzed the variations in the paths cyclists rode through the intersections. Data were collected on several variables related to both the cyclists and their interactions with the site itself such as helmet use and riding through crosswalks. Path analysis required the development a new evaluative variable in order to compare individual paths by how much deviation there was in each path ridden as compared to other cyclists. Site-specific surveys addressed the perceptions, bicycling experience, demographics, and path and route preferences by cyclists at both shared space and control intersections. The analysis indicated that cyclists rode similarly through both shared and control intersections, and that a large percentage of riders preferred to ride farther from motor vehicles when given the space to do so. This project offered further insight in how to best design shared space projects for nonmotorized users by looking at the spatial layout and the elements that most influenced a rider’s path choice. Results indicated that, in these cases, shared space was not the panacea for nonmotorized users as some literature suggests, but nonetheless appeared to be a valid form of traffic calming. This research offered further insight in how to best design shared space projects for nonmotorized users by looking at the spatial layout and the elements that most influenced a rider’s path choice.

Text in Hebrew with English Summary / This research describes nominal patterns with prefixes m and t as appearing in Parma A in comparison with other traditions viz. Kaufinan, Paris and Y emenite manuscripts. This research has 3 aims: 1. To describe all relevant evidence in Parma A 2. To compare evidence with data in other traditions, including the Bible and Mishnaic Hebrew and Aramaic sources 3. To elaborate on those unique forms in manuscripts which represent genuine Mishnaic Hebrew / Classics and Modern European Languages / D. Litt et Phil. (Semitic Languages)