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Guardrails were designed to deter vehicle access to off-road areas and consequently prevent hitting rigid fixed object alongside the road (e.g., trees, utility poles, traffic barriers, etc.). However, guardrails cause 10% of deaths of vehicle-to-fixed object crashes which has attracted attention in the highway safety community on the vehicle-based injury criteria used in guardrail regulations. The objectives of this study were 1) to develop and validate a Finite Element (FE) model of the ET-Plus, a commonly used energy-absorbing guardrail end terminal; 2) to examine the conditions of in-service end terminals, and to evaluate the performance of the damaged relative to undamaged end terminals in simulated impacts; 3) to investigate both full-body and body region driver injury probabilities during car-to-end terminal crashes using dummy and human body FE models; to analyze the relationship between the vehicle-based crash severity metrics used currently in regulations and the injury probabilities assessed using biomechanics injury criteria; and 4) to quantify the influence of pre-impact conditions on injury probabilities. In this dissertation, an ET-Plus FE model was developed based on publicly available data on ET-Plus dimensions and material properties. The model was validated against the NCHRP-350 crash tests. The developed ET-Plus model was used to develop to five damaged ET-Plus whose damage patterns were identified based on an investigation of in-service end terminals mounted along U.S. roads. It was observed that damaged end terminals usually increase collision severity compared to undamaged end terminals. Meanwhile, a total of 40 FE impact simulations between a car with a dummy/human body model in the driver seat and an end terminal model were performed in various configurations. The vehicle-based severity metrics were observed to be correlated to full-body and certain body-region injury risks while no head injury risk could be predicted. The results pointed out that more advanced vehicle-based metrics should be proposed and investigated to improve the predictability in terms of occupant injury risks in the crash tests. The simulation models could also supplement crash compliance tests of new hardware designs, by investigating their safety performance for a large variety of pre-impact conditions, observed in traffic accidents, but not included the compliance tests. / Doctor of Philosophy / Guardrails were designed to deter vehicle access to off-road areas and consequently prevent hitting rigid fixed object alongside the road (e.g., trees, utility poles, traffic barriers, etc.). However, guardrails cause 10% of deaths of vehicle-to-fixed object crashes which has attracted attention in the highway safety community on the vehicle-based injury criteria used in guardrail regulations. The objectives of this study were 1) to develop and validate a Finite Element (FE) model of the ET-Plus, a commonly used energy-absorbing guardrail end terminal; 2) to examine the conditions of in-service end terminals, and to evaluate the performance of the damaged relative to undamaged end terminals in simulated impacts; 3) to investigate both full-body and body region driver injury probabilities during car-to-end terminal crashes using dummy and human body FE models; to analyze the relationship between the vehicle-based crash severity metrics used currently in regulations and the injury probabilities assessed using biomechanics injury criteria; and 4) to quantify the influence of pre-impact conditions on injury probabilities. In this dissertation, an ET-Plus FE model was developed based on publicly available data on ET-Plus dimensions and material properties. The model was validated against the NCHRP-350 crash tests. The developed ET-Plus model was used to develop to five damaged ET-Plus whose damage patterns were identified based on an investigation of in-service end terminals mounted along U.S. roads. It was observed that damaged end terminals usually increase collision severity compared to undamaged end terminals. Meanwhile, a total of 40 FE impact simulations between a car with a dummy/human body model in the driver seat and an end terminal model were performed in various configurations. The vehicle-based severity metrics were observed to be correlated to full-body and certain body-region injury risks while no head injury risk could be predicted. The results pointed out that more advanced vehicle-based metrics should be proposed and investigated to improve the predictability in terms of occupant injury risks in the crash tests. The simulation models could also supplement crash compliance tests of new hardware designs, by investigating their safety performance for a large variety of pre-impact conditions, observed in traffic accidents, but not included the compliance tests.

The majority of car crash deaths occur in the front seats because the majority of occupants sit in the front seats. Traditionally, the rear seats were safer than the front seats because a front seated occupant would be closer to rigid structures such as the steering wheel, and they would be closer to the location of the impact. Therefore, government crash test regulations as well as academic and industry testing up to this point have principally focused on the front seats. Since the beginning of efforts to make cars safer, innovations were applied to the front seats first. Only some of these safety innovations have transitioned into the rear seats. Over the years, the front seats have gotten much safer due to advanced seatbelts with pretentioners and load limiters, airbags surrounding the driver, and structural changes to the vehicle frame to prevent intrusion into the occupant compartment. At the same time, occupant safety in the rear seats has also improved, however at only a fraction of the improvement of the front seats. With modern vehicles, the front seats have actually become safer than the rear seats for certain occupants and specific crash types (e.g., adult occupants in frontal crash). The lagging performance of the rear seats represents a problem because thousands of rear-seated occupants are injured or killed each year. With the rise in autonomous driving systems, the amount of occupants sitting in the rear seats, and therefore sustaining injury, could increase dramatically. In this dissertation, rear seats of a range of current vehicles were reconstructed to examine injury risk with the finite element models of two anthropomorphic test devices. These models showed a wide range of injury risks in the reconstructed seats. They were also able to show results similar to sled impact tests with the same vehicles. Knowledge gained from these reconstructions was then used to perform parametric studies on key variables that influence injury risk in the rear seats. From the parametric studies, it was found that the seat back angle, the width of the seatbelt anchors, and the presence of a seatbelt pretensioner had the largest influences on the injury risk. One of the injury mechanisms prevalent in the rear seats is submarining. Submarining likelihood and injury probability is difficult to predict with anthropomorphic test devices; however, human body models can help to improve injury prediction in these cases. To improve the injury prediction capability of human body models, several additions to the models are necessary. This dissertation outlines the investigation of spleen and kidney shapes through statistical shape analysis. This type of analysis allows more customizable human body models which could better capture the injury probability to these organs for a wider range of the population. Finally, subject-specific models of ribs were created to investigate factors affecting the predictive capability of finite element models. The findings and methodology from this body of work have the ability to add critical contributions to the understanding of injury risk and injury mechanisms in the rear seats. / Doctor of Philosophy / The majority of car crash deaths occur in the front seats because the majority of occupants sit in the front seats. Traditionally, the rear seats were safer than the front seats because a front seated occupant would be closer to hard objects such as the steering wheel, and they would be closer to the location of the impact. Therefore, government crash test regulations as well as academic and industry testing up to this point have principally focused on the front seats. Since the beginning of efforts to make cars safer, technology such as seatbelts and airbags were applied to the front seats first. Only some of this technology has been added into the rear seats. Over the years, the front seats have gotten much safer due to all the work focused on the front seats. At the same time, the rear seats have also improved, however at only a fraction of the improvement of the front seats. With modern vehicles, the front seats have actually become safer than the rear seats in some cases. The lagging performance of the rear seats represents a problem because thousands of rear-seated occupants are injured or killed each year. With the rise in self driving cars, the amount of occupants sitting in the rear seats, and therefore sustaining injury, could increase dramatically. In this dissertation, rear seats of a range of current vehicles were reconstructed to examine injury risk with the models of two crash test dummies. These models showed a wide range of injury risks in the reconstructed seats. They were also able to show results similar to physical tests with the same vehicles. Knowledge gained from this work was then used to help look at key variables that influence injury risk in the rear seats. It was found that the angle of the seat back, the width of the seatbelt anchors, and the presence of advanced seatbelts had the largest influences on the injury risk. One of the injury mechanisms prevalent in the rear seats is submarining, where the seatbelt slides up off the hips. Submarining likelihood and injury probability is difficult to predict with crash test dummies; however, human body models can help to improve injury prediction in these cases. To improve the injury prediction capability of human body models, several additions to the models are necessary. This dissertation outlines the investigation of spleen and kidney shapes to allow more customizable human body models which could better capture the injury probability to these organs for a wider range of the population. Finally, subject-specific models of ribs were created to investigate factors affecting the predictive capability of rib models. The findings and methodology from this body of work have the ability to add critical contributions to the understanding of injury risk and injury mechanisms in the rear seats.

Buildings account for 40% of energy consumption in the US. Despite all improvements in buildings shell, equipment, and design, CO2 emissions from buildings are increasing as a result of increased energy consumption. Since occupants spend more than 90% of their time indoors, they are inseparable and significant elements of building system dynamics. Hence, there is a great potential for energy efficiency in buildings using a wide range of programs such as education, intervention, energy feedback, etc. Due to advancement of technology and accessibility of high resolution energy consumption data, utility companies are enabled to focus on implementing energy feedback programs to induce energy efficiency and reduce the peak energy load in the commercial and residential sector. In order to better understand various aspects of energy feedback programs, in the first chapter of this dissertation, I conduct a comprehensive literature review on the state-of-the-art energy feedback study methods and identify gaps of knowledge and challenges faced by researchers in the field. Accordingly, the future research vision is laid out at the intersection of methods and gaps of knowledge used in energy feedback studies and future research opportunities and questions are provided. One of the major gaps of knowledge I identified in the literature review is the lack of quantitative analyses used to investigate the variability of occupant responses to commercial buildings energy feedback programs to evaluate the need for targeted and tailored energy feedback programs. In the second chapter, I conducted a comprehensive analysis on occupant energy-use responses under the influence of a uniform energy feedback program. Furthermore, I investigated the effectiveness of notifications on increasing the level of engagement of the occupants in these studies. The results supported the existence of a variability in responses and engagement level in a uniform energy feedback program which may be due to intra-class variability of occupant behavior. In the third chapter, based on the established need for a targeted energy feedback program, I investigate the predictability of occupant energy consumption behavior and its correlation with energy consumption. The results report that 46% of occupants may be good candidates for targeted energy feedback programs due to their combination of higher levels of energy-use and predictability of their energy consumption behavior. / Ph. D.

Historically, rear seat occupants have been at a lower risk of serious injury and fatality in motor vehicle crashes than their front seat counterparts. However, many passive safety advancements that have occurred over the past few decades such as advanced airbag and seatbelt technology primarily benefit occupants of the front seat. Indeed, safety for front seat occupants has improved drastically in the 21st century, but has it improved so much that the front seat is now safer than the rear? Today, rear-seated occupants account for 10% of all passenger vehicle fatalities. In this era focused on achieving zero traffic deaths, the safety of rear-seated occupants must be further addressed. This dissertation analyzed U.S. national crash data to quantify the risk of injury and fatality to rear-seated passenger vehicle occupants while accounting for the influence of associated crash, vehicle, and occupant characteristics such as crash severity, vehicle model year, and occupant age/sex. In rear impacts, the risk of moderate-to-fatal injury was greater for rear-seated occupants than their front-seated counterparts. In high-severity rear impact crashes, catastrophic occupant compartment collapse can occur and carries with it a great fatality risk. In frontal impacts, there is evidence that the rear versus front seat relative risk of fatality has been increasing in vehicle model years 2007 and newer. Rear-seated occupants often sustained serious thoracic, abdomen, and/or head injuries that are generally related to seatbelt use. Seatbelt pretensioners and load limiters – commonplace technology in the front seating positions – aim to mitigate these types of injuries but are rarely provided as standard safety equipment in the rear seats of vehicles today. Finally, in side impacts, injury and fatality risks to rear- and front-seated occupants are more similar than in the other crash modes studied, though disparities in protection remain, especially in near-side vehicle-to-vehicle crashes. Finally, this work projects great injury reduction benefits if a rear seat belt reminder system were to be widely implemented in the U.S. vehicle fleet. This dissertation presents a comprehensive investigation of the factors that contribute to rear-seated occupant injury and/or fatality through retrospective studies on rear, front, and side impacts. The overall goal of this dissertation is to better quantify the current risk of injury to rear-seated occupants under a variety of crash conditions, compare this to the current risk to front-seated occupants, and, when possible, identify how exactly injuries are occurring and ways in which they may be prevented in the future. The findings can benefit automakers who seek to improve the effectiveness of rear seat safety systems as well as regulatory agencies seeking to improve was vehicle tests targeting rear seat passenger vehicle safety. / Doctor of Philosophy / Historically, if a passenger vehicle such as a sedan or SUV is in a crash, occupants who are rear-seated were less likely to be hurt than someone who was front-seated. In other words, rear-seated occupants have been at a lower risk of injury than front-seated occupants. Indeed, safety for front seat occupants has improved drastically in the 21st century due to advancements in airbag and seatbelt technologies, among others, but has it improved so much that the front seat is now safer than the rear? Today, of all vehicle occupants who are killed in crashes on U.S. roadways, 10% are rear-seated. During this time when conversations surrounding vehicle safety are focused on achieving zero traffic deaths, the safety of rear-seated occupants must be further studied. This dissertation looked at national databases of all police-reported crashes that occur each year in the United States. The risk of injury to rear-seated passenger vehicle occupants was quantified and compared to that of front-seated occupants. Factors that may increase or decrease this risk of injury and fatality such as crash type, vehicle type, and occupant demographics were further explored and reported. In vehicles that were rear-ended, the risk of injury was greater for rear-seated occupants than their front-seated counterparts. When a vehicle crashes into something front-first (the most common type of impact in a vehicle crash), evidence is presented that the risk of fatality is greater in the rear seats than the front seats in model year 2007 and newer vehicles which generally are equipped with the most recent airbag and seatbelt technology. When a vehicle is hit on either of its sides, the risk of injury is closer between rear- and front-seated occupants than it was in the rear-end or frontal crashes previously studied. That said, differences in occupant protection were still observed between the rear and front seats, especially when the occupants studied were seated on the closest side of impact, or the near-side, and the vehicle was struck by another vehicle rather than sliding into an object such as a pole. Finally, this work projects great injury reduction benefits if a rear seat belt reminder system were to be widely implemented in the U.S. vehicle fleet. This dissertation presents a comprehensive investigation of the factors that contribute to rear-seated occupant injury and/or fatality through retrospective studies on rear, front, and side impacts. The overall goal of this dissertation is to better quantify the current risk of injury to rear-seated occupants under a variety of crash conditions, compare this to the current risk to front-seated occupants, and, when possible, identify how exactly injuries are occurring and ways in which they may be prevented in the future. The findings can benefit automakers who seek to improve the effectiveness of rear seat safety systems as well as regulatory agencies seeking to improve was vehicle tests targeting rear seat passenger vehicle safety.

This work addresses the problem of localizing an impact in a dispersive medium (waveguide) using a network of vibration sensors (accelerometers), distributed at various locations in the waveguide, measuring (and detecting the arrival of) the impact-generated seismic wave. In particular, the last part of this document focuses on the problem of localizing footsteps using underfloor accelerometers. The author believes the outcomes of this work pave the way for realizing real-time indoor occupant tracking using underfloor accelerometers; a system that is tamper-proof and non-intrusive compared to occupant tracking systems that rely on video image processing. A dispersive waveguide (e.g., a floor) causes the impact-generated wave to distort with the traveled distance and renders conventional time of flight localization methods inaccurate. Therefore, this work focuses on laying the foundation of a new alternative approach to impact localization in dispersive waveguides. In this document, localization algorithms, including wave-signal detection and signal processing, are developed utilizing the fact that the generated wave's energy is attenuated with the traveled distance. The proposed localization algorithms were evaluated using simulations and experiments of hammer impacts, in addition to occupant tracking experiments. The experiments were carried out on an instrumented floor section inside a smart building. As will be explained in this document, energy-based localization will turn out to be computationally cheap and more accurate than conventional time of flight techniques. / PHD / When a person walks, each footstep impact generates a tiny floor-quake. The floor-quake sends a shock wave traveling along the floor, and causes the floor to vibrate. If these vibrations are sensed/measured at different locations in the floor, then the measurements can be used to estimate the individual footstep impact locations. Estimating the location of each footstep impact can then be utilized to track the walking path of the person. This dissertation proposes a novel footstep location estimation approach. The localization approach uses a group of underfloor vibration sensors, called accelerometers, to measure the footstep-generated floor vibration. Then, the sensor measurements are used to estimate footstep locations. Footstep location estimates are generated using the fact that the strength/energy of the generated wave is absorbed by the floor, and consequently the wave energy is attenuated with the traveled distance. The proposed footstep localization approach can be used to track occupants inside buildings, providing a tracking system that is non-intrusive compared to tracking occupants using a system of cameras and a video image-processing software.

In developed nations, 20-40% of greenhouse gas emissions and more than one-third of energy consumption are attributable to buildings. Among various available strategies, the building sector has the greatest potential for carbon emission reduction. Leadership in Energy and Environmental Design (LEED) took early action to promote sustainable designs in buildings and has become the most well-known rating system in the field of building sustainability. However, little research has evaluated the effects of LEED on occupant pro-environmental behavior. To examine this, a Post-Occupancy Evaluation (POE) was conducted in a traditional, green featured, and LEED certified building case to compare the similarities and differences in environmental awareness, perceptions, and perceived ease or difficulty of pro-environmental behaviors, as well as to assess the degree to which pro-environmental behaviors were exhibited by occupants. This was used to determine if the aforementioned factors influence occupant behavior in different building cases. Ease or difficulty of pro-environmental behaviors and environmental awareness were found to be significant factors in influencing pro-environmental behavior in the LEED certified and green featured building cases. In addition, being in a LEED building appears to influence occupant pro-environmental behavior in a positive way. Also, there is evidence to suggest that being in a green featured building appears to influence occupants to exhibit pro-environmental behavior as well. These findings are valuable for owners and designers that want occupants in their buildings to exhibit pro-environmental behavior. / Master of Science / Climate change is an issue that has risen to national and global importance with the increase of rising sea levels, temperature and precipitation, and extreme weather events. To combat the issue of climate change, changes in building design through the avenue of green rating systems have been used to encourage the building sector to reduce energy consumption and thus, a building’s environmental impact. LEED (Leadership in Energy and Environmental Design), is one of the most well-known green rating systems used to rate energy efficient buildings. However, the effect of LEED on occupant pro-environmental behavior has been less studied in understanding how occupant behavior impacts energy consumption in a traditional, green featured, and LEED certified building case. This thesis aims to explore if occupying different buildings influence occupants to exhibit proenvironmental behaviors. For this study, I investigated whether occupant’s environmental awareness, perceptions, perceived ease or difficulty of set behaviors and pro-environmental behavior differed between different building cases. This thesis concludes that being in a LEED certified and green featured building appear to influence occupants to exhibit pro-environmental behavior, more so than being in a traditional building.

"Numerous higher education (HE) institutions in the United States (US) have created sustainability agendas, including construction of sustainable buildings. More than 200 US HE institutions, have at least one Leadership in Energy and Environmental Design (LEED) certified building on their campus (Princeton Review 2012). With the growing student population and need to house them, residence hall construction is rising nationwide. A profile of newly constructed building types shows residence halls hold the largest median area (Princeton Review 2012). In an effort to assess if sustainable residence halls are performing sustainably, a series of post occupancy evaluation (POE) indicators were selected. POE indicators were chosen through a review of widely adopted sustainability rating systems, scientific literature and student occupant feedback. The selected indicators address a range of parameters including: water and energy consumption, occupant thermal comfort, occupant consumption behavior and education, noise insulation (indoor and outdoor), and Facilities Management (FM) operational feedback. Furthermore, specific indicators such as building energy management systems (BEMS), building automation control systems (BACS) and artificial intelligence (AI) agents were examined. The proposed POE indicator framework data was collected from various key stakeholders including: designers, HE FM departments, residential life personnel, and student occupants. The dataset includes: actual temperature (T) and relative humidity (RH) measurements of a LEED-Gold residence hall, actual water (9 residence halls) and energy consumption (4 residence halls) data, and feedback from designers, HE FM departments and 593 student occupants (LEED and non-LEED residence halls). The proposed POE indicator framework triangulates quantitative and qualitative data, via investigative and diagnostic techniques; creating a comprehensive building performance picture, vis-à-vis technical and non-technical parameters."

Motor vehicle accidents are statistically the major cause of accidental severe injuries for pregnant women and fetuses fatality. Volunteers, post mortem human surrogates, anthropomorphic crash test devices and computational occupant models are used to improve human safety in motor vehicle accidents. However, due to the ethical issues, pregnant women and their fetuses cannot be used as volunteers or post mortem human surrogates to investigate the effects of crashes on them. The only anthropomorphic test device representing pregnant women is very limited in design and lacks a fetus. There is no computational pregnant occupant model with a fetus other than 'Expecting'. This thesis focuses on understanding the risk of placental abruption for pregnant drivers involved in road accidents, hence assessing the risk to fetus fatality. An extensive review of existing models in general and pregnant women models in particular is reported. The time line of successive development of crash test dummies and their positive effect on automotive passive safety design are examined. 'Expecting', the computational pregnant occupant model with a finite element uterus and a multibody fetus, is used in this research to determine the strain levels in the uteroplacental interface. External factors, such as the effect of restraint systems and crash speeds are considered. Internal factors, such as the effect of placental location in the uterus, and the inclusion and exclusion of a fetus are investigated. The head of the multibody fetus is replaced with a deformable head model to investigate the effects of a deformable fetus head on strain levels. The computational pregnant driver model with a fetus offers a more realistic representation of the response to crash impact hence provides a useful tool to investigate fetus safety in motor vehicle accidents. Seat belt, airbag and steering wheel interact directly with the pregnant abdomen and play an important role on fetus safety in motor vehicle accidents. The results prove that the use of a three-point seat belt with the airbag offer the greatest protection to the fetus for frontal crash impacts. The model without a fetus underestimates the strain levels. The outcome of this research should assist automobile manufacturers to address the potential safety issues at the design level.

The thesis presents an investigation of pregnant women s safety and comfort needs during car travel. A survey is used to investigate all aspects and problems of car travel. This survey is a comprehensive examination of the entire driving activity with much detail of reported difficulties from pregnant women that forms a novel resource for the automotive engineers. The survey results are used to generate guidelines for the automotive industry. A series of sled tests are presented that investigate seat belt use in pregnancy including the use of lap belt positioners. The peak abdominal pressure results clearly agree with current guidelines that the lap belt should be positioned across the hips and not across the abdomen. This research includes a novel anthropometric dataset for 107 pregnant women including measurements especially selected for the field of automotive design and to describe the changes of pregnancy. This includes investigation of pregnant driver s proximity to the steering wheel. A novel measurement of knee splay is used to define the pregnant women s preference to sit with their knees widely spaced instead of knees together, in both normal sitting and in a car. Comparison is made between the pregnant women's measurements and the available data in the literature for non-pregnant women and males, and this shows that pregnant women can be excluded from designs if the accommodation does not consider their needs. The pregnant women's anthropometric data is presented as a novel website in order to make the data available to the automotive industry. This website is generated for use by automotive engineers and is designed to suit their usability needs and the general trends within the industry, in order to make the site more user-friendly and more likely to be used as a reference for pregnant occupant's needs.