Anscombe (1964) presents influential arguments that 'before' and 'after' cannot denote converse relations, despite intuitions to the contrary. These arguments, I claim, rely on ambiguity of certain 'before'- and 'after'-sentences, ambiguity that arises from the interaction of tense and aspect with the temporal ordering relations denoted by 'before' and 'after'. To account for this ambiguity, I adopt a Discourse Representation Theory-based analysis of tense and aspect (Kamp & Reyle 2011) and apply it to a set of examples that exhibit the variety of readings available for 'before'- and 'after'-sentences. I argue that certain readings of stative 'after'-sentences support the existence of an inceptive coercion operator, equivalent in effect to the aspectual verb 'begin'. This operator has much in common with 'earliest', an operator proposed by Beaver & Condoravdi (2003), but it is motivated by independent aspectual considerations. I conclude with a discussion of areas for future research. / text

Doctor of Philosophy / Department of Industrial & Manufacturing Systems Engineering / Malgorzata J. Rys / Centerline rumble strips (CLRS) are effective in preventing cross-over crashes and are promoted in the United States (U.S.) as a low-cost safety measure. However, there may be negative issues and/or concerns that question their use under certain road conditions. This dissertation is the result of studying these issues and concerns to provide guidance to policy makers on future installations of CLRS, based on current good practices and on the results of specific investigations of exterior noise, safety effectiveness, economics, and drivers’ behavior, including their interaction with shoulders and shoulder rumble strips (SRS). From a survey conducted, good practices in the U.S. were summarized. From a before-and-after study of CLRS safety effectiveness, results showed that total correctable crashes were reduced by 29.21%. Crashes involving fatalities and injuries were reduced by 34.05%. Cross-over crashes were reduced by 67.19%, and run-off-the-road crashes were reduced by 19.19%. Both Naïve and Empirical Bayes methods were applied and showed statistically similar results. There was no statistical difference between football shaped and rectangular shaped CLRS. From the external noise study performed, it was found that external noise depends on vehicle speed, type of vehicle, and distance. Both football and rectangular CLRS substantially increased the levels of external noise at distances up to 45 m (150 ft). Therefore, before installing CLRS, the distance from houses or businesses should be considered. A distance of 60 m (200 ft) was recommended as the limit of the potential exterior noise problem area. From a study of drivers’ behavior, the analyzed configurations of rumble strips and shoulder width levels affected vehicular lateral position and speed levels, although speed deviations were not practically significant. The study of safety performance function models provided technical and economical recommendations for installation of CLRS. Overall, this study recommends the installation of CLRS on rural, two-lane, undivided rural roads in Kansas. Both patterns, rectangular and football, currently installed in Kansas have provided crash reductions, which have been reflected in economic benefits for society. Shoulder width and traffic volume should be considered as crash predictors for enhancement of the benefits. Guidelines were recommended for future better applications of CLRS.

<p>This Dissertation includes a statistical analysis of traffic accidents followed by a test to know the effect of new pavement on traffic safety. The accident data is considered for the roads those are in Region South-East Sweden that got new pavement during the year 2001. In Sweden, this is the fourth study concerning the before and after effect of the new pavement. Johansson (1997) studied the change in the number of accidents between the before-years and after-years. Tholén (1999) and Velin et al (2002) have additionally compared the change with the change in the number of accidents in a reference road network (also called control sites) consisting of all public roads in Region West Sweden which were not resurfaced during the study period.</p>

This Dissertation includes a statistical analysis of traffic accidents followed by a test to know the effect of new pavement on traffic safety. The accident data is considered for the roads those are in Region South-East Sweden that got new pavement during the year 2001. In Sweden, this is the fourth study concerning the before and after effect of the new pavement. Johansson (1997) studied the change in the number of accidents between the before-years and after-years. Tholén (1999) and Velin et al (2002) have additionally compared the change with the change in the number of accidents in a reference road network (also called control sites) consisting of all public roads in Region West Sweden which were not resurfaced during the study period.

While weaving maneuvers occur on every type of roadway, most studies have focused on freeway maneuvers. Weaving occurring on non-freeway facilities, such as arterial streets, can cause significant operational problems. Arterial streets weaving typically occur when vehicles coming from a side street at an upstream intersection attempt to enter the main street from one side to reach access points on the opposite site at a downstream intersection by crossing one or more lanes. This dissertation investigates the type of problems occurring on arterial streets due to the weaving movements and recommends a new design to alleviate weaving on arterial streets. Firstly, the dissertation examined the different weaving movements occurring between two close-spaced intersections at two sites in Florida and explained the breakdown conditions caused by the weaving movements at the two sites. Secondly, the dissertation proposed a new design, Right Turn Split (RTS), to alleviate the delay caused by the weaving movements. The new design proposed separating the worst weaving movement entering the arterial from the other movements and providing a separate path for this movement. The new method is easy to implement and does not require much right of way. Thirdly, the dissertation compared two microscopic models, SimTraffic and VISSIM, to choose the most suitable model to be used to study the operational benefits of the RTS design. Based on the results of the comparison, it was decided to use SimTraffic for the analysis. Fourthly, the dissertation proposed a new calibration and validation procedure for microscopic simulation models. The procedure was applied on SimTraffic using the traffic data from the two studied sites. The proposed procedure appeared to be properly calibrating and validating the SimTraffic simulation model. Finally, the calibrated and validated model was used to study the operational benefits of the RTS design. Using a wide range of geometric and volume conditions, 729 before and after pairs were created to compare the delay of similar scenarios before and after applying the RTS design. The results were analyzed graphically and statistically. The findings of the analysis showed that the RTS design provided lower delay on the arterial street than the original conditions.

The purpose of this thesis is to explore how the installations of traffic signals affect crash experience at intersections, to identify those factors which help predict crashes after a signal is installed, and to develop a crash prediction model. It is the intent of this thesis to supplement the Manual on Uniform Traffic Control Devices Signal Warrant procedure and aid the traffic engineer in the signal installation decision making process. Crash data, as well as operational and geometric factors were examined for 32 state road intersections in the northeast Florida area before and after signal installation. Signal warrant studies were used as sources for traffic volumes, geometric information and crash history, before signal installation. The Florida Department of Transportation's Crash Analysis Reporting System (CARS) was used to gather crash data for the time period after signal installation. On average, the 32 intersections experienced a 12% increase in the total number of crashes and a 26% reduction in crash rate after signals were installed. The change in the number of crashes was not significant, but the rate change was significant with 90% confidence. Angle crash frequency dropped by 60% and the angle crash rate dropped by 66%, both are significant. Left-turn crashes dropped by 8% and their rate by 16%, although neither was significant. Rear-end crashes increased by 86% and the rear-end crash rate decreased by 5%. Neither of these changes was statistically significant. When crash severity was examined, it was found that the number of injury crashes increased by 64.8% and the rate by only 0.02%. Neither change was significant. Both the number of fatal crashes and the rate decreased by 100% and were significant. Property Damage Only (PDO) crashes increased by 96%, after signalization, but this change was not significant. The PDO rate, however, decreased by 46.5% and is significant. Operational factors such as AADT, turning movement counts, and speed limits; and geometric factors such as medians, turn lanes and numbers of lanes were considered to determine their effect on crashes at signalized intersections. Smaller roads, with low AADT, fewer lanes, and a rural character were found to benefit from signalization more than busier urbanized roads, in terms of crash rate reduction. The AADT, roadway cross section, number of lanes, medians, speed limit and left turn volume were all found to be important factors influencing crash rates. This thesis recommends: 1) the use of crash prediction models to supplement the MUTCD Crash Warrant, 2) the addition of a left-turn warrant to the MUTCD signal warranting procedure, and 3) development of an intersection database containing crash data as well as operational and geometric information to aid in future research.

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Master of Science / Department of Civil Engineering / Sunanda Dissanayake / Construction of by-pass lanes at rural intersections typically has been considered a low-cost safety improvement. Safety analysis utilizes two common approaches to evaluate treatment effectiveness: before-and-after study and cross-sectional study. This research performed paired sample t-test statistical analysis to estimate changes in total of crash frequency, crash rates, EPDO crash frequency, and EPDO crash rates at intersections, three to five years after adding a by-pass lane compared to identical time period before the by-pass lane was added. Crash data between 1990 and 2011 were obtained from Kansas Crash and Analysis Record System (KCARS) maintained by the Kansas Department of Transportation (KDOT). In order to perform a cross-sectional study, intersections with by-pass lanes were compared to intersections with no countermeasures; crash data were obtained for more than 1,100 intersections in the state of Kansas. According to before-and-after study, addition of by-pass lanes improves safety at unsignalized rural intersections; crashes and their severities are reduced after adding by-pass lanes. But, these reductions are not statistically significant under 95% confidence level. However, when considering intersection related crashes, a statistically significant reduction in crash rates is happened after adding by-pass lanes at 3-legged intersections. In cross-sectional study, crashes and their severities are lower at 3-legged intersections with the by-pass lanes versus 3-legged intersections without the by-pass lanes. However, these reductions are not statistically significant under 95% confidence level. When considering 300 feet intersection crash box, statistically significant reductions are happened at 4-legged intersection. In contrast, crashes and their severities increased at 4-legged intersections with the by-pass lanes, but these changes are not statistically significant under 95% confidence level. The Crash Modification Factors were calculated to evaluate safety effectiveness of adding by-pass lanes at unsignalized rural intersections. The calculated CMFs less than 1.0, indicate a reduction in crashes after implementation of by-pass lanes. Finally, this study concluded that expected crashes at intersections with by-pass lanes are lower than intersections without by-pass lanes.

Bakgrund: 1 januari 2013 kommer Direktivet (2009/138/EG) för Solvens II att implementeras. Detta kommer ske samtidigt inom Europeiska Unionen (EU) och kommer leda till en harmonisering av försäkringslagstiftning i medlemsstaterna. Tidigare svensk lagstiftning, Försäkringsrörelselagen (2010:2043), kommer med andra ord att anpassas till det nya regelverket. Regeländring kan komma att påverka svenska försäkringsbolags bedrivna kapitalförvaltning. Syfte: Syftet med studien är att undersöka om svenska försäkringsbolag utifrån rådande lagstiftning kan bedriva en, enligt finansiell teori, rationell kapitalförvaltning och om möjligheten till att bedriva en rationell kapitalförvaltning kommer att förändras i och med implementeringen av Solvens II. Genomförande: En genomgång av dagens regelverk, Försäkringsrörelselagen, samt Direktivet (2009/138/EG) för Solvens II kommer att presenteras. Utöver detta har fem stycken intervjuer med svenska försäkringsbolag genomförts. Slutsats: Dagens lagstiftning ger inte möjligheter till att bedriva en rationell kapitalförvaltning fullt ut. Solvens II kommer att förbättra försäkringsbolagens möjligheter att bedriva en rationell kapitalförvaltning. Försäkringsbolagen bedriver idag en förvaltning som till stor del kan anses vara rationell utifrån finansiell teori. Dock finns det vissa områden inom förvaltningen som skiljer sig från teorins bild. / Background: January 1, 2013, Directive (2009/138/EC) of Solvency II will be implemented. This will take place simultaneously in the European Union (EU) and will lead to a harmonization of insurance laws of the member states. Former Swedish legislation, Försäkringsrörelselagen (2010:2043), will therefore be adapted to the new framework. The rule change may affect Swedish insurance companies’ asset management. Purpose: The purpose of the thesis is to examine if Swedish insurance companies can apply rational asset management theory when Solvency II is implemented and if changes will occur in the asset management strategies. Implementation: A review of current regulations, Försäkringsrörelselagen (2010:2043), and Directive (2009/138/EC) of Solvency II will be presented. In addition, five interviews with Swedish insurance companies have been done. Conclusion: The current legislation does not provide opportunities to fully apply rational asset management. Solvency II will improve the insurance companies' ability to pursue a rational asset management. The asset management in Swedish insurance companies currently adopts strategies that to high extent comply with generally accepted financial theories. However, there are certain areas within the asset management that deviate from these financial theories.