This study emphasizes the extreme variability present in traffic speed studies and the need for high resolution traffic and weather data in order to understand the interaction between traffic speeds and weather. I analyzed the impact rainfall has on roadway traffic speeds along I-65 in Indiana for the month of June 2018 and attempted to leverage this information to model and predict traffic speeds. To develop a statistical distributional understanding of the difference between traffic speeds under rain and non-rain conditions, Quantile-Quantile plots were generated in addition to fitting both scenarios to a gamma distribution. To compare how traffic speeds react to various precipitation intensities, boxplots were generated for comparison. Then, a baseline speed was defined using the median traffic speed under non-rain scenarios and was used to calculate speed reductions from the baseline at varying precipitation intensities. Finally, an XGBoost model is developed to attempt traffic speed predictions. There are five key findings indicated by this study. First, the non-rain traffic speeds above the 5th percentile are typically faster than their rain speed counterparts at comparable quantile levels. Second, traffic speeds exhibit a high amount of variance at varying precipitation intensity levels. Third, the gamma distribution does not suit traffic speed distributions at all locations and times of day under rain or non-rain scenarios. This result is consistent with previous findings that suggest traffic speed interactions are highly variable and based on a variety of factors that are hard to account for. Fourth, weekday traffic speeds from 1600 to 2200 UTC are the most strongly impacted across all regions during rain events seeing speed reductions of up to 10 mph, this is consistent with previous findings. Finally, the XGBoost model did not perform adequately in the configuration used in this study. The poor performance of the XGBoost model was somewhat anticipated as this study did not have access to traffic volume information and instead leverages proxy variables to account for this. The findings of this study demonstrate the need for finer scale studies on traffic—weather interactions and provides methodology that can be extended to other weather and traffic datasets.

This thesis project focuses on the verification method of a safety function called PICthat stands for Post-Impact Control which controls the vehicle motion of passengercars after being exposed to external disturbances produced by a 1st impact, aiming atavoiding or mitigating secondary events.The main objective was to select a promising method, among several candidates, todevelop further for testing the function and the interaction with the driver. To do thisis was first necessary to map the real destabilized states of motion that are targeted bythe function. These states are referred as Post-Impact problem space and are acombination of variables that describes the host vehicles motion at the instant thedestabilizing force has ceased. Knowing which states are requested by the solutioncandidates, it is possible to grade the rig candidates based on the capability ofcovering the problem space. Then, simulating the proposed rig solutions withMatlab/Simulink models to investigate which candidate fulfils best the problem space.The result of the simulations and other criteria is that a moving base simulator(Simulator SIM4) is most fitted to research verification. The second mostadvantageous solution is the rig alternative called Built-in Actuators.

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Thesis. 1975. M.S.--Massachusetts Institute of Technology. Dept. of Nuclear Engineering. / Includes bibliographical references. / This is a report of the experimental results of a program in countercurrent flow critical heat flux. These experiments were performed with Freon 113 at 200 psia in order to model a high pressure water system. An internally heated annulus was used to model a fuel pin in a channel. Only low flowrates were examined. The flow regime was always bubbly or slug, with the liquid primarily on the walls. It was found that critical heat flux of about .9 of the pool boiling value can be expected for up to 20% void. Beyond this, the CHF value decreases uniformly with void. Void fractions up to 70% were investigated, with the results being slightly conservative compared to a similar experiment carried out at atmospheric pressure by Avedisian. / M.S.

Thesis. 1977. Nucl.E.--Massachusetts Institute of Technology. Dept. of Nuclear Engineering. / M̲i̲c̲ṟo̲f̲i̲c̲ẖe̲ c̲o̲p̲y̲ a̲v̲a̲i̲ḻa̲ḇḻe̲ i̲ṉ A̲ṟc̲ẖi̲v̲e̲s̲ a̲ṉḠS̲c̲i̲e̲ṉc̲e̲. / Includes bibliographical references. / by Farid Bamdad-Haghighi. / Nucl.E.

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE / Includes bibliographical references. / by John Jay McCauley. / B.S.

The problem is to determine the circumstances and conditions prerequisite to liability under attractive nuisance as it applies to public schools in the State of California. In answering this problem an attempt will be made to clarify for the school administrator sundry areas in attractive nuisance, as follows: 1) What constitutes the action of negligence?; 2) What is the history of the attractive nuisance doctrine in England where it originated, and in the United States?; 3) What is the attractive nuisance doctrine as recognized in the State of California?; 4) What distinction does California make between negligence and attractive nuisance as they apply to school districts?; 5) What are possible situations under which lawsuits in attractive nuisance may culminate into judgments against school districts?; 6) Why have California courts to date rendered no decision on attractive nuisance against a school district?

M.Sc. (Eng.),Faculty of Engineering and the Built Environment, University of the Witwatersrand, 2012 / Mining is a sensitive business that yields high returns and at the same time is associated with high risk of injuries/fatalities and potential losses of revenue. There is increasing intolerance for injuries and fatalities by governments and the other stakeholders involved in the mining business often resulting in mine closures and revenue loss. Chief among the mining risks is the occurrence of rockfalls where people work and access. The rockfalls are bound mainly by joints that intersect the rockmass thereby forming rock blocks that may fall once an excavation has been created. There are many methods that have been used over time to predict the occurrence of rockfalls. More recently probabilistic methods have gained more ground over deterministic methods. The properties of the joints that are identifiable on exposed excavations are the main inputs used in simulating rockfalls. To date there has been little work that has been done to compare predicted rockfalls to actual rockfalls. This dissertation presents a practical method for collecting rockfall and joint data in the stope hangiwall at two mines in the Bushveld Complex. The joint data has been used in simulating rockfalls using JBlock (a probabilistic keyblock stability programme). A comparison between simulated rockfalls and mapped rockfalls has been presented. Based on this comparison, a number of iterations were done to calibrate the JBlock results until near realistic rockfalls were achieved. Three case studies have been conducted to investigate the effectiveness of different stope support systems in reducing rockfall. The potential losses and injury risk associated with the different support systems have been quantified for all the individual rockfalls. In general the rockfall frequency is directly proportional to the risks associated with the rockfalls. Through this research it has been demonstrated that it is possible to use joint data found on excavation surfaces to statistically predict the occurrence of potential rockfalls in similar ground conditions. The optimum support system that has minimum injury and cost risk can also be selected from a comparison of a number of support systems. Armed with this information, rock engineers can now make strategic decisions versus the existing common tactical approach.

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