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The work presented in this thesis concerns the identification of vehicle occupant models. Mathematical models of the vehicle occupant are used in the preliminary design and development phase of vehicle design. In the design phase, the model is used to guide the decision on restraint system feasibility. In the development phase the model is used to suggest solutions to problems associated with the dummy trajectory or restraint system performance. Current methods used -to determine such models involve independent component testing. The conditions under which the components are tested are often not typical of a crash test, hence iterations of the computer model are needed to successively improve model and test correlation. In order to address these problems which cause inaccurate specification of the mathematical models, an alternative method of data set assembly for crash victim models is suggested. This alternative method is based on the techniques of system identification which allow unknown system parameters to be determined from experimental input/output data. Initially the viability of using system identification techniques to develop a valid mathematical model of the vehicle occupant and restraint system was investigated. This initial study used input and output measurementsfr om computer simulations of the occupant in frontal impact, as source data for the identification. Effects of simulated disturbances (noise corrupted output signals) and the effects of simplified model structure on the identification are also investigated. Several methods for analysing the likely errors in the identified parameters are defined and discussed in this simulation study. Results relating to the identification of seat contact and seat belt characteristics from physical tests are also presented and these are interpreted in light of the simulation results.

Reduction of carbon emissions is understood to be vital to help mitigate catastrophic climate change. In Europe, 40% of energy use is attributed to the built environment (European Commission, 2010), with a large proportion of this from dwellings. In line other legislation for decarbonisation under the Climate Change Act of 2008, the UK Government has agreed that all new housing will be ‘zero carbon’ from 2016 onwards. From a technical aspect this task is feasible using improved insulation performance, more airtight building techniques, efficient servicing, and renewable energy technologies. In practice however, post-occupancy evaluation studies highlight a discrepancy between design energy use and measured energy performance, with a tendency for real buildings to use more energy than designed and for projects regarded as ‘low energy’ in design to use an equivalent amount of energy as a pre-existing counterpart (Bordass, 2001; Branco, Lachal, Gallinelli, & Weber, 2004; Gill, Tierney, Pegg, & Allan, 2011). This difference between design and use - ‘the design gap’ - is attributed to both the physical ‘hard’ features of the building (form, area, systems) and occupant-driven or ‘soft’ features (ventilation & heating preferences) by a number of studies (Guerra Santin, Itard, & Visscher, 2009; Socolow, 1978). This body of work begins with a review of the field and state of the art - occupant influence on energy use in a domestic environment. The first contribution to knowledge is in the adapted utilisation of a piece of software by Richardson et al. which stochastically generated electricity use profiles for homes which are shown to be similar to measured energy usage, both in net energy use and in load profiles (Richardson, Thomson, & Infield, 2008). This adapted software was implemented to generate appliance use profiles for a number of dwelling models. These results are then interrogated and a regression model proposed based on a number of dependent variables identified in the input profiles. The theory of planned behaviour is used to underpin a survey in which a number of households are asked to comment on their attitude and behaviour with regards to energy use in the home – the homes in this case being new-build Passivhaus council-housing in Devon. The results of this project form the second aspect of this work’s contribution to knowledge.

Office buildings in hot humid Singapore appear to be designed for stable and uniform indoor conditions. It is proposed in this thesis that this is unnecessary, as occupant comfort expectations do not warrant it and energy is wasted as a result. A comfort-based approach to design is advocated, as a means of balancing user needs with the objective of energy conservation.This issue of how perception of comfort is linked with indoor stability emerged from the question, 'why do office buildings, despite Bioclimatic prescriptions for hot humid conditions, continue to be predominantly climate rejecting and active-run?' The literature was found to be polarised by arguments for architectural solutions that are climatically responsive and present lower energy costs, and those for engineered solutions that deliver greater, more consistent comfort, albeit through reliance on electro-mechanical systems.It is argued that comprehending the gaps in the literature, and between theory and application, requires a better understanding of occupant comfort. This would be an inside-out view of comfort and climate, predicated on how the occupant is affected by the building and the cognitive nature of comfort itself.Relying on a sample of office buildings, the thesis set out to establish the following:Prevalence of the climate-based approach, specifically Yeang's Bioclimatic ModelPrevalence of uniformity and stability of the indoor environmentOccupant perception of indoor comfort, both thermal and visual, particularly with regard to variability of ambient conditionsOccupant perception of various operational modes: passive, mixed and activeThese goals were addressed through observations of form, envelope and layout, occupant surveys and the monitoring of buildings in passive and active modes.It was found that the Bioclimatic approach is non-existent in the context of the Singapore office ++ / building. In the case of two Bioclimatic buildings in Malaysia, the Model is not consistently applied. This disparity appears partly due to conflicting priorities, in particular style, cost and client pressures, and partly due to assumptions about occupant comfort.The Singapore office building was found to be predominantly active-run, operating within a narrow bandwidth of temperatures across most spaces. Occupant perception of variability outside the primary workplace, however, is one of acceptance, even preference. It was found through analysis of user feedback that the office building, on the basis of comfort expectations, could be divided into three activity zones: Work, Support and Transit.This 3-tiered structure was subsequently tested through a large-scale, longitudinal survey carried out across three spaces, each representing an activity zone, within a single building. The survey was accompanied by adjustments to the building's temperature settings to test the limits of acceptance in each zone. Findings from this exercise support the notion of a three-zoned office building, in which thermal conditions for each zone could be varied without affecting comfort. Energy figures that were monitored before and after the resetting showed drops of 7.1 % in chiller consumption and 2.9% in overall consumption.These findings led to a comfort-based, tri-modal proposal for office buildings in hot humid conditions, defined as the Psychoclimatic Model for its basis in comfort expectations and the interaction between climate, building and the occupant.The implications of the thesis outcome on regulatory control in Singapore and thermal comfort theory are discussed. Recommendations are made for future research into other building types and national context, plus a parametric study into the full energy-saving potential of the Psychoclimatic Model.

The Passivhaus standard is a building methodology that was established in Germany in the 1990s. It uses a passive design strategy to achieve built environment comfort with minimum energy consumption. However, research shows that not every Passivhaus project has been successful in terms of its comfort and energy performance. Passivhaus is a representation of a high-performance, low-energy prototype of sustainable buildings, which, as a new building typology, embraces new ideas of comfort and accommodates a range of occupants who have different attitudes and expectations. Thus, the social grounding of such a new typology needs to be reconsidered. Understanding the phenomenon of Passivhaus living in the UK context forms the starting point of my research. In reflection of existing Passivhaus post-occupancy evaluation (POE) research in the UK, the majority of this research is focused on performance and frequently adopts an approach using prediction and computer simulation. Only a few studies have examined the Passivhaus system from an architectural design point of view. Research into its energy performance lacks a deeper connection with the occupants' perception of comfort and the architectural design of the Passivhaus. This research focuses on the coherence of Passivhaus living and builds up a theoretical framework to understand the Passivhaus system in relation to occupants' daily lives. It argues that by providing more possibilities and opportunities within the design of the built environment for adaptive behaviours and norms of sustainable living, as opposed to stressing energy efficiency and technological advances, the sustainability embodied in the Passivhaus standard can be further actualised. Previous research into the POE field of Passivhaus has employed a predominantly quantitative method. However, the small amount of research conducted using a qualitative approach demonstrates the potential benefits of gaining a better understanding of sustainability in people's perceptions of comfort, their everyday practices and the nature of their energy use. The methodological approach for the proposed research will be qualitative in nature due to the need to understand highly context-bound experiential data. A mixed approach of quantitative and qualitative methods will be explored to collect and analyse data from various aspects related to the subject matter in order to draw valid conclusions. The research uses a combined framework of grounded theory methodology and a multiple case study approach as a way of taking a step back from empirical research and building up an inductive theory-building process. The combination of these two frameworks is tailored for this research, which enables them to complement each other. The research provides an exploration of Passivhaus living and an insight into the delicate relationship between the occupants and their domestic space. The study explores the shifting perception of comfort, the delicate relationship between habitat and inhabitant and the process of adaptation in the Passivhaus to understand the shaping of household behaviour in relation to different contexts and scenarios unique to the Passivhaus industry. The substantive theory that describes this relationship is summarised at the end of the thesis, with the aim of informing potential Passivhaus clients of the system's holistic sustainable design features and to make recommendations for better Passivhaus design to building professionals.

A computationally efficient multilevel decomposition and optimization framework is developed for application to automotive structures. A full scale finite element (FE) model of a passenger car along with a dummy and occupant restraint system (ORS) is used to analyze crashworthiness and occupant safety criteria in two crash scenarios. The vehicle and ORS models are incorporated into a decomposed multilevel framework and optimized with mass and occupant injury criteria as objectives. A surrogate modeling technique is used to approximate the computationally expensive nonlinear FE responses. A multilevel target matching optimization problem is formulated to obtain a design satisfying system level performance targets. A balance is sought between crashworthiness and structural rigidity while minimizing overall mass of the vehicle. Two separate design problems involving crash and crash+vibration are considered. A major finding of this study is that, it is possible to achieve greater weight savings by including dummy-based responses in optimization problem.

As societies evolve, offices have become the places were the majority of working activities take place. Occupants’ comfort in office buildings has always been a very important issue in the building sector and therefore guidelines regarding indoor comfort standards have been developed throughout the years. Nevertheless, there is a need for investments on new and innovative ideas which will go beyond the existing guidelines and move towards a more sustainable and human oriented office environment.The present thesis aims at promoting this idea of sustainable offices by developing and presenting an innovative technological method which will provide the opportunity to measure the office workers’ perceived comfort in real time. This in its turn will enable the building sector stakeholders to operate office buildings in a more sustainable way in terms of building services provision to their occupants.In order to achieve these objectives, the first part of the thesis is dedicated in describing the basic indoor environmental components of the office environment as well as the possible associations between improved indoor environmental quality and occupants’ health, wellbeing and productivity. The second part aims to provide a detailed presentation of the existing or emerging methods which are currently used in order to predict or directly measure occupants’ perceived comfort in office places while in the same time discussing their current capabilities and limitations. In the final part, our proposed method, which could be used for the purposes of real time perceived comfort measurements, is presented. This proposed method includes four different steps which are separately presented with detailed instructions regarding their proper implementation.

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The indoor environmental quality (IEQ) of buildings can have a strong influence on occupants’ productivity and health. Post occupancy evaluation (POE) is the first step in assessing IEQ, and typically relies on subjective surveys of thermal quality, air quality, visual quality, and acoustic quality. However, the practice of conducting POE, from data collection during field studies to data coding, analyses and visualization, is very labor intensive. In addition, there is often a significant discrepancy between major IEQ standards and actual human perception. The Center for Building Performance and Diagnostics (CBPD) at Carnegie Mellon University (CMU) has expanded POE to include both objective IEQ measurements and records of the TABS that may affect indoor environment and user satisfaction. The suite of three tools including user satisfaction survey, technical attributes of building system and workstation IEQ measurements in the National Environmental Assessment Toolkit has been deployed in over 1600 workstations in 65 buildings, generating a rich database for statistical evaluation of the possible correlations between the physical attributes of workstations, measured environmental conditions, and user satisfaction. The database also supports a number of critical hypotheses relative to the complexity and depth of field data needed, the critical factors that must be collected, and the possibility that humans are indeed good sensors for many variables. The major statements that have been drawn from the research are as follows: (1) Because human health and performance outcomes are a result of an integration of indices, IEQ evaluation must include thermal, air, visual, and acoustic measures. (2) While POE with IEQ measurement is an ideal approach to assessing the full suite of environmental characteristics that impact human satisfaction, health and performance, field measurements are labor and cost intensive. (3) Building occupants can provide critical insights and even real measures of IEQ, and contribute to updating IEQ standards to reflect integrated realities. As such, this research revealed an integrated approach to POE +M by leveraging occupants as sensors to quickly capture IEQ conditions in a work environment. This approach can identify critical factors in the physical environment that impacts building occupant comfort and satisfaction. This approach provides practical IEQ assessment methods and procedures centered on the occupants’ perspective. The ultimate outcome of this research will contribute (1) correlations between occupant perception and measured data, (2) a refined survey method to assess building IEQ capable of robust prediction of building performance, and (3) metrics and guidelines for IEQ standards that capture new IEQ thresholds that impact building occupants’ comfort. The hypotheses tested in this thesis are summarized as follows: Hypothesis 1: Humans are effective sensors for POE+M. Combining occupant responses with key IEQ attributes can provide insight that is comparable to complex field instrumentation. Hypothesis 2: User satisfaction can inform design decisions. Comparing user satisfaction to instrumented IEQ measurements can inform acceptable thermal, air, visual, and acoustic design for occupant satisfaction. Hypothesis 3: Environmental thresholds are not adequate. Comparing user satisfaction to instrumented IEQ measurements can inform acceptable thermal, air, visual, and acoustic quality l conditions for occupant comfort. Multivariate regression, multiple correlation coefficient, and Pearson correlation statistical analysis of the database of 1600 workstations revealed the relationship between measured and perceived IEQ indices, interdependencies between IEQ indices and other satisfaction variables of significance. This research can contribute correlations between occupant perception and measured conditions, and metrics and guidelines for IEQ standards that capture new IEQ thresholds that impact building occupants’ comfort. The key findings of the IEQ data analysis are as follows: The result of the thermal quality revealed that smaller thermal zone, greater window quality, a level of control, measured air temperature at 60 cm from the floor, and radiant temperature asymmetry between exterior and interior walls are critical factors of temperature satisfaction. For air quality, operable windows, window quality, partition height, dedicated exhausts for printer and copy area, return air density are critical factors for overall air quality satisfaction. User satisfaction of the visual quality showed that seated view in the workstation is the most critical factor for user’s overall visual quality satisfaction. In addition, better ceiling fixture, ceiling lens type, window type and managing illuminance level on the work surface are important. Lastly, to ensure the acoustic quality satisfaction in both background noise and frequency from distraction from other people, bigger workstation, more partition sides, higher partitions and management of distributed noise source are critical for user comfort and perceived productivity. Overall, this thesis identified opportunities to improve the process of IEQ assessment by engaging occupants in POE, and define critical indicators for building occupant satisfaction. The results will contribute to the ongoing database of engaging humans as IEQ sensors. In the future, the findings and framework described here may be applied in different aspects of the building delivery process, such as building life cycle evaluation, building design, and the construction stage, to improve occupants’ thermal, air, visual, and acoustic conditions in the building.

Every year, millions of people are killed or injured in motor vehicle accidents in the United States. Although recent improvements to occupant restraint systems, such as seatbelts and airbags, have significantly decreased life threatening injuries, which usually occur to the chest or head, they have done little to decrease the occurrence of lower extremity injuries. Although lower extremity injuries are not usually life threatening, they can result in chronic disability and high psychosocial cost. Of all lower extremity injuries, injuries to the knee-thigh-hip (KTH) region have been shown to be among the most debilitating. This project used a finite element (FE) model of the KTH region to study injury. A parametric investigation was conducted where the FE KTH was simulated as a vehicle occupant positioned to a range of pre-crash driving postures. The results indicate that foot contact force and knee kinematics during impact affects the axial force absorbed by the KTH region and the likelihood of injury. The results of the study could be used to reevaluate the lower extremity injury thresholds currently used to regulate vehicle safety standards. Also, the results could be used to provide guidelines to vehicle manufacturers for developing safer occupant compartments.