The research in this thesis was conducted to investigate the initial stage of passing maneuvers on a rural, two-lane, two-way (RTLTW) highway with centerline rumble strips (CRSs). Four measures of effectiveness were used: (1) number and type of erratic movements by a passing vehicle, (2) number of and time between centerline encroachments of a passing vehicle, (3) gap distance of a passing vehicle, and (4) centerline crossing time. Data were collected for a before-and-after analysis at one site, in Comanche County, Texas. The test section was on US 67 from Comanche, Texas to the county line south of Dublin, Texas. The posted speed limit for this RTLTW highway was 70 mph during the day. CRSs were installed along approximately 15 miles of US 67. Only one test design for CRSs was installed. The design specification was for a CRS to be milled to a 0.5-inch depth, 7-inch length, and 16-inch width. This specification was developed from current state practices throughout the United States. CRSs were installed continuously through passing and no-passing zones, and they were spaced at 24 inches on-centers. Pavement markings were striped over the CRSs. Data were collected using an innovative data collection system developed by the author through the Texas Transportation Institute (TTI). This system was mounted to a four-door sedan, and it consisted of four concealed cameras that recorded the entire passing maneuver around the data collection vehicle. Data were collected at three different speeds during the daytime. The speeds were 55, 60, and 65 mph (15, 10, and 5 mph, respectively, under the posted speed limit). Based on the assessment of the four MOEs, the overall finding of this thesis was that driver performance during the initial phase of passing maneuvers was not negatively impacted after the installation of CRSs on US 67. The caveat is that differences in the weather conditions may have influenced the results. The weather was dry with clear skies at the study site during data collection prior to the installation of CRSs; however, the weather consisted of intermittent rain during the data collection after the installation of CRSs.

Notre travail de recherche étudie l'organisation et le fonctionnement du système foncier comorien en prenant en compte les périodes précoloniale, coloniale et post-coloniale. Ce système incarne bien le reflet de la juxtaposition des structures traditionnelles et coloniales. Il a surtout subi, dans ses modes d'acquisition le poids des trois types bien distincts de droits (coutumier, musulman et colonial). Le choix de cette période, nous a permis d'effectuer une recherche sur la situation des dysfonctionnements de ce système à la veille, pendant la colonisation française et jusqu'à l'après accession du pays à la souveraineté internationale en 1975. Notre approche méthodologique consiste à présenter ; d'abord, de plus près et d'une manière exhaustive, les permanences, les mutations et les défis des modes d'acquisition (succession, donation, contrat de vente ou d'échange, accession, prescription...). Elle analyse, en même temps, les caractéristiques générales et spécifiques de l'environnement socioculturel sur l'organisation foncière de l'Archipel des Comores. Elle présente, enfin, les éventualités et les approches des politiques agraires qui doivent favoriser la mise en place des instruments juridiques d'une véritable politique de sécurisation des propriétés et domaines en maintenant l'équilibre d'un environnement écologique approprié et un développement durable et humain. / This purpose of this research is to attempt to study how the Comorian land ownership system as regards its organization functioning during the pre-colonial, colonial and post colonial period. This system actually reflects the side by side existence of both traditional and colonial structures. It has however undergone deep changes with three different types of ownership, the customary, the Islamic and the colonial modes of property acquisition. The choice of this time frame is deliberate since it has enabled us to analyze the weakness of the system before, during colonial period and up to the independence in 1975. This study will first look closely and exhaustively at the permanent mode property acquisition continuous changes and challenges related to the mode of property acquisition such as inheritance, donation, sale contract, exchange, accession and prescription. At the same time, it will examine the general and specific features of the socio cultural context. Finally it will present the possibilities and land policies leading to a written document for regulation estate and land while keeping a balanced ecological environment in relation to a true policy promoting human sustainable and development.