Дисертації з теми "Occupant mechanics"

The influence of building occupancy and user behaviour on energy usage has been identified as a source of uncertainty in current understanding of operational buildings, and yet it is rarely directly monitored. Gathering data on the occupancy of buildings in use is essential to improve understanding of how energy is used relative to the actual energy requirements of building users. This thesis covers the application of occupancy measurement and processing techniques in order to address the gap in knowledge around the contextual understanding of how occupants’ changing use of a building affects this building’s optimum energy demand in real time. Through targeted studies of running buildings, it was found that typical current occupancy measurement techniques do not provide sufficient context to make energy management decisions. Useable occupancy information must be interpreted from raw data sources to provide benefit: in particular, many slower response systems need information for pre-emptive control to be effective and deliver comfort conditions efficiently, an issue that is highlighted in existing research. Systems utilising novel technologies were developed and tested, targeted at the detection and localisation of occupants’ personal mobile devices, making opportunistic use of the existing hardware carried by most building occupants. It was found that while these systems had the potential for accurate localisation of occupants, this was dependent on personal hardware and physical factors affecting signal strength. Data from these sources was also used alongside environmental data measurements in novel algorithms to combine sensor data into a localised estimation of occupancy rates and to estimate near-future changes in occupancy rate, calculating the level of confidence in this prediction. The developed sensor combination model showed that a selected combination of sensors could provide more information than any single data source, but that the physical characteristics and use patterns of the monitored space can affect how sensors respond, meaning a generic model to interpret data from multiple spaces was not feasible. The predictive model showed that a trained model could provide a better prediction of near-future occupancy than the typically assumed fixed schedule, up to an average of approximately two hours. The systems developed in this work were designed to facilitate the proactive control of buildings services, with particular value for slower-response systems such as heating and ventilation. With the application of appropriate control logic, the systems developed can be used to allow for greater energy savings during low or non-occupied periods, while also being more robust to changing occupant patterns and behaviours.

For women of reproductive age, automobile crashes are the leading cause of death worldwide. It has been estimated that 40,000 women in the second half of pregnancy are involved in motor-vehicle crashes each year. It has been estimated that between 300 to 3800 will experience a fetal loss. Placental abruption has been shown to account for 50% to 70% of fetal losses in motor vehicle crashes. While there is a growing database of medical case studies and retrospective studies describing the outcome of motor vehicle accidents involving pregnant occupants, as well as the effect of seatbelts on fetal survival, previous research has not produced a tool for engineers to use to improve the safety of a pregnant occupant in a motor vehicle. The goal of this project was to develop a model that can quantify the stresses and strains on the uterus of a pregnant woman in order to predict the risk of injury. A finite element uterine model of a 7-month pregnant female was created and integrated into a multi-body human model. Unrestrained, 3-pt belt, and 3-pt belt plus airbag tests were simulated at speeds ranging from 13 kph to 55 kph. Peak uterine strain was found to be a good predictor of fetal outcome. The uterine strain sufficient to cause placental abruption was seen in simulations known to have greater than 75% risk of adverse fetal outcome. Head injury criteria (HIC) and viscous criterion (V*C) were examined as a check of overall occupant protection. The 3-pt belt plus airbag restraint provided the greatest amount of protection to the mother. The model proved successful at predicting risk of fetal demise from placental abruption and verified experimental findings noting the importance of proper restraint use for the pregnant occupant.
Master of Science

A child dies in road traffic crashes every fourth minute. Totally were 186 300 children under the age of 18 killed in vehicle accidents in 2012, even more were severely injured [1]. The World Health Organisation (WHO) could conclude that fatalities in traffic accidents are more likely to occur in low- to middle income countries compared to high income countries [1]. Finite element based human body models has enabled the increased understanding of kinematics and injury mechanisms of child occupants. These models sustain higher biofidelity than the previously used crash test dummies. The European project PIPER [6] had the aim to develop a model that, combined with a framework, would simplify positioning and also to offer a scalable HBM child model. The PIPER framework software and the scalable PIPER model offers child HBM:s within the ages 1.5-6-years old and is an useful tool for the analysis of child occupants.    The present study evaluates the kinematics and dummy responses of the 4- and 6-year old PIPER model evaluated. The objective of this master thesis is to evaluate the PIPER model with respect to its sensitivity to seat belt geometries, child restraint system, load cases and child anthropometrics. The aim of the master thesis is to get an increased comprehension of the PIPER model and its capability to evaluate occupant kinematics relevant for safety developments, with a special focus on seat belt geometry and interaction in frontal impacts.   The PIPER model showed good sensitivity to different seatbelt geometries regarding the abdominal part of the shoulder belt and to different CRS. The PIPER framework was perceived as hard to use and with the presence of errors. The kinematic response showed good accuracy compared to other previous studies with other crash test dummies however, reoccurring error termination could not be neglectable.    The PIPER model is limited to its ease to positioning in desired sitting postures within the PIPER framework. It is regardless of its disadvantages believed to be a suitable tool to further understand occupant kinematics, as for different belt routings, child anthropometrics and dummy responses are further studies needed to validate the outputs that the model offers and to conclude its robustness in crashworthiness tests.

Habitat modification is the primary cause of amphibian population declines worldwide. Some species survive in modified habitats whereas others become restricted to small, isolated forest patches. Although many studies compare species richness and composition between modified and intact habitats, the factors and mechanisms that maintain biodiversity in these landscapes are poorly understood. I asked how life history traits and habitat features influence interspecific variation in frog occupancy patterns in tropical pasture and forest. To identify mechanisms underlying occupancy patterns, I used experiments to examine how abiotic conditions in different habitats influence the vital rates of tadpoles. I also explored whether tadpoles use a carnivorous foraging strategy to improve performance in nutrient-poor, ephemeral pools in pasture. Although modified and intact habitats offer abiotic environments that differ in quality for frogs, pastures contribute to the maintenance of biodiversity in fragmented landscapes. I detected an equal number of species but substantially different assemblage composition in forest and pasture. Species that occurred in pasture had different traits than those in forest, including larger body sizes, larger clutch sizes, larger geographic ranges, and reproductive modes that depend on water. The occurrence of pasture-specialists was associated with habitat features at small spatial scales, whereas the occurrence of forest-specialists was associated with habitat features at small and large spatial scales. An experiment indicated that abiotic conditions in pastures may deter or facilitate adult movements to breeding sites. Behavioral selection of sites by two model species was consistent with tadpole performance. Tadpoles of a pasture-specialist performed well across the pasture-forest gradient, but abiotic conditions in pasture facilitated faster growth and development than in edge or forest. In contrast, tadpoles of a forest-specialist performed well only in edge and forest. Most tadpoles occupying ephemeral pasture pools were facultative carnivores or cannibals of eggs and hatchlings. Tadpoles may contribute to the regulation of assemblages in pasture pools, influencing the relative abundance and composition of species through differential predation on eggs and hatchlings. The study of factors and mechanisms that contribute to population growth or decline of species can facilitate understanding of assemblage-level patterns of amphibian diversity in modified landscapes.

In this Thesis Project, the creation of a Low Energy building was examined in order to investigate how complex was to select the suitable parameters and systems of the dwelling, aiming to achieve the lowest possible energy consumption in one year period. All the technologies implemented into the system intended to be as energy efficient and profitable as possible. Another objective of this study was also to present the potential of the system to produce a part of the consumed energy, through renewable energy sources, approaching by this way also the standards of a Zero Energy Building. Firstly, the floor plan of the 150 m2 detached house, was drawn in the designing program AutoCAD. In continuation, this 2D floor plan was imported into the simulation program as well as all the initial input data so as for the Base model of the building to be created For the analysis of the building, the Simulation Program IDA ICE 4.7 was used. Gradually, alternations and adjustments were made into the Base model. Different models were created planning to analyze their results and conclude to the proper solution. All the simulations run for one year time period in order to present the total energy usage, system’s losses and demands in each case. In addition, as for the current study, the location of the construction was Athens, all building’s characteristics were chosen to comply with the Greek Regulation for Low Energy Buildings. Finally, through the procedure followed after having accomplished a series of simulations, the final annually energy demands managed to be within the required limits.

Online Presentation

The goal of this dissertation is to demonstrate that data from a remotely located building can be utilized for energy modeling of a similar type of building and to demonstrate how to use this remote data without physically moving the data from one server to another using Virtual Information Fabric Infrastructure (VIFI). In order to achieve this goal, firstly an EnergyPlus model was created for Greek Life Center, a campus building located at University of North Texas campus at Denton in Texas, USA. Three thermal comfort models of Fanger model, Pierce two-node model and KSU two-node model were compared in order to find which one of these three models is most accurate to predict occupant thermal comfort. This study shows that Fanger's model is most accurate in predicting thermal comfort. Secondly, an experimental data pertaining to lighting usage and occupancy in a single-occupancy office from Carnegie Mellon University (CMU) has been implemented in order to perform energy analysis of Greek Life Center assuming that occupants in this building's offices behave similarly as occupants in CMU. Thirdly, different data types, data formats and data sources were identified which are required in order to develop a city-scale urban building energy model (CS-UBEM). Two workflows were created, one for an individual scale building energy model and another one for CS-UBEM. A new innovative infrastructure called as Virtual Information Fabric Infrastructure (VIFI) has been introduced in this dissertation. The workflows proposed in this study will demonstrate in the future work that by using VIFI infrastructure to develop building energy models there is a potential of using data for remote servers without actually moving the data. It has been successfully demonstrated in this dissertation that data located at remote location can be used credibly to predict energy consumption of a newly built building. When the remote experimental data of both lighting and occupancy are implemented, 4.57% energy savings was achieved in the Greek Life Center energy model.

Les modèles d'occupation de niche au sein des communautés locales, la variabilité spatiale de la biodiversité le long des gradients environnementaux du stress et des perturbations, et les processus de succession végétale sont plusieurs sujets fondamentaux en écologie. Récemment, l'approche basée sur les traits est apparue comme un moyen prometteur de comprendre les processus structurant les communautés végétales et cette approche a même été proposée comme méthode pour reconstruire l'écologie communautaire en fonction des traits fonctionnels. Par conséquent, lier ces thèmes fondamentaux en utilisant une lentille fonctionnelle devrait nous donner un aperçu de certaines questions fondamentales en écologie et sera l'objectif principal de ma thèse. En général, mon projet de doctorat vise à étudier les structures de l'occupation de l'espace fonctionnel dans les gradients spatio-temporels. Plus précisément, l'objectif du chapitre 2 est (i) d'étudier les modèles d'occupation de la niche fonctionnelle en calculant trois métriques clés de niche (le volume total de niche fonctionnelle , le chevauchement des niches fonctionnelles et le volume de niche fonctionnel moyen) des communautés pauvres en espèces aux communautés riches en espèces et (ii) de déterminer le principal facteur de la structure observée de l'occupation de la niche fonctionnelle dans les communautés végétales du monde entier. Dans le chapitre 3, je vise à prédire et à expliquer la variation de la richesse en espèces selon les gradients de stress et de perturbation, en reliant le modèle d'équilibre dynamique et l'occupation de la niche fonctionnelle en fonction du cadre développé au chapitre 2. L'objectif du chapitre 4 est de tester expérimentalement l’application d'une méthode d'ordination CSR évaluée globalement en fonction de trois traits de feuilles (surface foliaire, teneur en matière sèche des feuilles et surface foliaire spécifique) dans les études locales. Enfin, l'objectif du chapitre 5 est de tester expérimentalement les hypothèses qui concilient les points de vue déterministes et historiquement contingents de la succession végétale, en étudiant la variation des divergences taxonomiques et fonctionnelles entre les communautés selon des gradients de stress et de perturbation. L'étude globale (chapitre 2) est basée sur une collection de 21 jeux de données, couvrant les biomes tropicaux et tempérés, et se compose de 313 communautés végétales représentant différentes formes de croissance. Les études locales (chapitre 3, 4 et 5) sont basées sur le même système expérimental constitué de 24 mésocosmes présentant différents niveaux de stress et de perturbation. L'expérience a commencé en 2009 avec le même mélange de graines de 30 espèces herbacées semées sur les 24 mésocosmes et s'est terminée en 2016. Nous avons permis la colonisation naturelle de graines de la banque commune de graines de sol et de l'environnement pendant la succession de sept ans. Dix traits ont été mesurés sur cinq individus (échantillonnés directement à partir des mésocosmes) par espèce par mésocosme en 2014 (chapitre 3 et 4). Un autre ensemble de traits (16 traits, y compris certains traits qui ne pouvaient pas être mesurés directement dans les mésocosmes), ont été mesurés au niveau de l'espèce (valeurs moyennes des traits) pour les 34 espèces les plus abondantes (certaines espèces disparues dans les mésocosmes) au cours des sept Ans, en les regroupant séparément pour une saison de croissance. Au chapitre 2, nous avons constaté que les communautés étaient plus diverses en termes fonctionnels (une augmentation du volume fonctionnel total) dans les communautés riches en espèces et que les espèces se chevauchaient davantage au sein de la communauté (augmentation du chevauchement fonctionnel), mais ne divisaient pas plus finement l'espace fonctionnel (aucune réduction du volume fonctionnel moyen). En outre, le filtrage de l'habitat est un processus répandu qui conduit à la caractérisation de l'occupation de niche fonctionnelle dans les communautés végétales. Dans le chapitre 3, nous avons trouvé un modèle similaire d'occupation de niche fonctionnelle sur un système expérimental avec une taille spatiale communautaire constante et un effort d'échantillonnage des traits, qui, avec le chapitre 2, nous a fourni une image plus complète et plus solide de l'occupation de niche fonctionnelle dans les communautés végétales. De plus, nous avons réussi à relier le modèle de l'occupation de la niche fonctionnelle et le modèle d'équilibre dynamique et avons constaté que le filtrage concurrentiel était le processus dominant qui détermine le mode d'occupation de la niche fonctionnelle et la richesse des espèces le long du stress et de la perturbation des gradients. Au chapitre 4, nous fournissons un soutien empirique à une méthode d'ordination CSR calibrée globalement en montrant une relation entre l'abondance relative d'espèces en croissance dans les mésocosmes ayant différents niveaux de fertilité du sol et mortalité indépendante de la densité et leur classification CSR. Au chapitre 5, nous avons montré que la succession d'installations au cours de sept ans dans ces mésocosmes était plus déterministe d'un point de vue fonctionnel, mais plus historiquement contingent d'un point de vue taxonomique et que l'importance relative de la contingence historique a diminué à mesure que l'environnement devenait plus stressé ou perturbé. En conclusion, les structures de l'occupation de l'espace fonctionnel dans (le volume fonctionnel total, le chevauchement fonctionnel et le volume fonctionnel moyen, les Chapitre 2 et 3) ou entre les communautés locales (dissimilarité fonctionnelle, chapitre 5) sont déterministes plutôt que neutres (ou contingence historique ). Les espèces tolératrices de stress sont plus avantagées dans les mésocosmes moins fertiles tandis que les espèces rudérales sont plus avantagées dans les mésocosmes avec plus de mortalité indépendante de la densité.
Abstract : The patterns of niche occupancy within local communities, the spatial variability of biodiversity along environmental gradients of stress and disturbance, and the processes of plant succession are several fundamental topics in ecology. Recently, the trait-based approach has emerged as a promising way to understand the processes structuring plant communities and has even been proposed as a method to rebuild community ecology based on functional traits. Therefore, linking these fundamental themes through a functional lens should give us more insight into some basic questions in ecology and will be the main objective of my thesis. Generally, my PhD project is to investigate the structures of functional space occupancy along both spatial and temporal gradients. Specifically, the objective of Chapter 2 is to investigate the patterns of functional niche occupancy by calculating three key niche metrics (the total functional niche volume, the functional niche overlap and the average functional niche volume) from speciespoor communities to species-rich communities and to determine the main driver of the observed pattern of functional niche occupancy across plant communities worldwide. In Chapter 3, I aim to predict and explain the variation of species richness along gradients of stress and disturbance, by linking the dynamic equilibrium model and functional niche occupancy based on the framework developed in Chapter 2. The objective of Chapter 4 is to experimentally test the application of a globally calibrated CSR ordination method based on three leaf traits (leaf area, leaf dry matter content and specific leaf area) in local studies. Finally, the aim of Chapter 5 is to experimentally test the hypotheses reconciling the deterministic and historically contingent views of plant succession, by investigating the variation of taxonomic and functional dissimilarities between communities along gradients of stress and disturbance. The global study (Chapter 2) is based on a collection 21 trait datasets, spanning tropical to temperate biomes, and consisting of 313 plant communities representing different growth forms. The local studies (Chapter 3, 4 and 5) are based on the same experimental system consisting of 24 mesocosms experiencing different levels of stress and disturbance. The experiment started in 2009 with the same seed mixture of 30 herbaceous species broadcast over the 24 mesocosms and ended in 2016. We allowed natural colonization of seeds from the common soil seed bank and from the surroundings during the seven-year succession. Ten traits were measured on five individuals (sampled directly from the mesocosms) per species per mesocosms in 2014 (Chapter 3 and 4). Another set of traits (16 traits including some traits that were not able to measured directly in the mesocosms) were measured at the species level (species mean traits values) for the 34 most abundant species (some species disappeared in the mesocosms) over the seven years, by regrowing them separately for one growing season. In Chapter 2, we found communities were more functionally diverse (an increase in total functional volume) in species-rich communities, and species overlapped more within the community (an increase in functional overlap) but did not more finely divide the functional space (no decline in average functional volume). Moreover, habitat filtering is a widespread process driving the pattern of functional niche occupancy across plant communities. In Chapter 3, we found a similar pattern of functional niche occupancy on an experimental system with a constant community spatial size and trait-sampling effort, which together with Chapter 2 provided us a more comprehensive and robust picture of functional niche occupancy across plant communities. In addition, we succeeded in linking the pattern of functional niche occupancy and the dynamic equilibrium model and found that habitat filtering was the dominant process determining the pattern of functional niche occupancy and species richness along the gradients stress and disturbance. In Chapter 4, we provide empirical support for a globally calibrated CSR ordination method by showing a relationship between the relative abundance of species growing in mesocosms having different levels of soil fertility and density-independent mortality and their CSR classification. In Chapter 5, we showed that plant succession over seven years in these mesocosms was more deterministic from a functional perspective but more historically contingent from a taxonomic perspective, and that the relative importance of historical contingency decreased as the environment became more stressed or disturbed. In conclusion, the structures of functional space occupancy within (the total functional volume, the functional overlap and the average functional volume; Chapter 2 and 3) or between local communities (functional dissimilarity, Chapter 5) are deterministic rather than neutral (or historical contingency). Stress-tolerators were more favored in high stress communities, while ruderals are more favored in high disturbed mesocosms (Chapter 4).

Typically, whiplash (low severity neck injury of for short LSNI) is associated with rear impacts. Due to this, there is a wide body of research investigating the mechanism of LSNI as a result of rear impact. Detailed studies into the prevalence of low severity neck injury show that this injury also occurs in front and side impacts (Stryke et al. 2012, Teamming et al., 1998, Jakobsson 1998, Morris et al., 1996, v Koch et. al. 1995,). This thesis is an investigation into low severity neck injury resulting from side impacts. An initial investigation into the Monash University Accident Research Centre database (Australia) and the Loughborough University Co-operative Crash Investigation Study (UK) was undertaken to identify the typical factors associated with LSNI from side impacts. These factors were then used to determine the real-world cases to be reconstructed later in the thesis. As the occupants involved in side impacts are exposed to large lateral accelerations that do not occur in rear impacts, the factors that are associated with LSNI from rear impact cannot automatically be assumed to be a relevant in side impacts. This thesis makes a contribution to research by identifying the factors associated with LSNI that are unique to this side impact. This work can guide future research into the development of human surrogates/ human models to ensure that they more accurately replicate side impacts at multiple impact angles (such as oblique angles), as this thesis shows that LSNI occurs at various side impact angles and not just at 90 degrees. A MADYMO human body model with detailed neck was used to simulate driver response in side impacts. To verify the output from the model, results from post mortem human subjects (PMHS) and live human volunteers, were used for comparison. The impact angles investigated in these trials were 90 degree lateral and 45 degree oblique. Six real world crashes were reconstructed using computer simulations undertaken in MADYMO (Mathematical Dynamic Modelling) and HVE (Human, Vehicle, Environment). Three different impact angles were analysed, namely 90 degree lateral near side, 90 degree lateral far side and 45 degree oblique near side. For each impact angle, two cases were reconstructed, one with an occupant receiving a low severity neck injury, and the other was a control case where the occupant did not receive a low severity neck injury. The methodology used in this thesis of determining crash acceleration (crash pulse) by using HVE has been used previously by researchers (Franklyn et al. 2003, 2005a, 2005b and Hasija et al. 2007, 2009) to investigate head injury. Hasija et al. (2007, 2009), when investigating head injury also programmed the determined the crash pulse (from HVE) into a MADYMO to reconstruct the occupant mechanics using a crash test dummy model.

The primary intervention for injury in children traveling in cars in Australia has involved the mandatory use of a restraint while traveling in a vehicle. This intervention has been successful as evidenced by high restraint usage rates by Australian children and substantial casualty reductions since the 1970’s. However casualty rates have been relatively stagnant over the last couple of decades. Currently more than 3,000 child occupants are seriously injured in Australia every year. There is a need to examine the scope for further preventing injury among restrained child occupants. This thesis presents four interrelated studies examining the factors and mechanisms involved when Australian children are seriously injured while using some form of restraint in a crash. Methods used include retrospective medical record review, in-depth crash investigation and analysis of mass in-depth crash data. Both descriptive and nonparametric statistical analysis techniques, including those that allow for the control of potential confounders, were used. Observations and results indicate there is substantial scope for further reducing serious injury in children traveling in cars in Australia. To realize this reduction there is a need to address the quality of restraint use by children through the development of strategies that not only encourage restraint use, but encourage the correct use of the most appropriate forms of restraint. There is also a need to address the protection provided by restraint systems and vehicles to child occupants in high severity crashes, and in crashes that involve impacts with fixed roadside objects such as trees and poles.

Heating, ventilation and air conditioning systems (HVAC) are the single largest consumer of energy in commercial and residential sectors. Minimizing its energy consumption without compromising indoor air quality (IAQ) and thermal comfort would result in environmental and financial benefits. Currently, most buildings still utilize constant air volume (CAV) systems with on/off control to meet the thermal loads. Such systems, without any consideration of occupancy, may ventilate a zone excessively and result in energy waste. Previous studies showed that CO₂-based demand-controlled ventilation (DCV) methods are the most widely used strategies to determine the optimal level of supply air volume. However, conventional CO₂ mass balanced models do not yield an optimal estimation accuracy. In this study, feed-forward neural network algorithm (FFNN) was proposed to estimate the zone occupancy using CO₂ concentrations, observed occupancy data and the zone schedule. The occupancy prediction result was then utilized to optimize supply fan operation of the air handling unit (AHU) associated with the zone. IAQ and thermal comfort standards were also taken into consideration as the active constraints of this optimization. As for the validation, the experiment was carried out in an auditorium located on a university campus. The results revealed that utilizing neural network occupancy estimation model can reduce the daily ventilation energy by 74.2% when compared to the current on/off control.