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ISO 26262 is a functional safety standard under development at the time of this thesis. It is an adaptation of the functional safety standard IEC 61508, aimed at development of automotive electrical/electronic systems. The version of ISO-26262 that was used and discussed in this thesis is the final draft released in January 2011. In this thesis, a subset of ISO-26262 is applied in the development of a safety critical driver assistance system for a Scania vehicle. The parts of ISO-26262 that are treated are Part 3: Concept phase, Part 4: Product development at the system level and Part 5: Product development at the hardware level. Throughout the thesis we evaluate ISO-26262 and report our experience of working with it. The driver assistance system under development, which ISO-26262 is applied to, is Collision Avoidance by Steering, a system that aims to avoid or mitigate rear-end collisions with vehicles in front by automatic steering of the vehicle.

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Ad hoc wireless networks are quite convenient local area networks. Because ad hoc wireless networks have a property what its topology is changed as hosts move. In order to efficiently and quickly broadcasting data, it is very important to have efficacious protocols in MAC (Medium Access Control) layer. In this paper, we propose a new broadcast protocol, Contention-based Broadcast Protocol (CBP). CBP is a TDMA-based protocol. There are three characteristics which make CBP an efficient protocol. They are (1) CBP utilize a backoff algorithm and some mini slot in contention request phase to avoid collisions. Most protocols do not implement a backoff algorithm. (2) A host only reserves a data slot each time instead of many slots in most TDMA-based protocol. It has the advantage of reducing the influence of host mobility because the time between a data slot is reserved and the time the data slot is utilized has greatly decreased, and (3) CBP differentiates unicast data and broadcast data and allows a host to reuse by channel for a unicast if it is impossible for a broadcast.

Wireless sensor networks typically consist of a significant number of low-cost sensor nodes which can collaborate among each other to execute a wide range of applications, such as environmental and health monitoring, intrusion detection, etc. Basically, sensor nodes are mainly battery-powered and have a limited amount of energy to spend, thereby they are not likely to be recharged or replenished after being deployed in an inaccessible sensed environment. As a result, in the past decade, power saving has become a critical issue for the design of a media access control (MAC) protocol in wireless sensor networks. By incorporating power-saving mechanism into MAC, we expect to maximize the lifetime of a sensor network. Intuitively, a large amount of research tends to make use of the TDMA protocol because it has inherently more favorable characteristics when compared to the CSMA protocol, that is, sensor nodes only need to wake up to transmit or receive data at its allocated time slots, and other time slots they can go into sleep mode. By doing so, it can reduce power consumption. However, in this master thesis, we found that there exists a rather acute problem, called the Multiple-Cluster Collision (MCC) problem, in the TDMA cluster-based protocol that will degrade the system performance drastically. Therefore, in this thesis, we propose the approach, called Multiple Cluster Collision Problem (MCCP), to perfectly eliminate the MCC problem by sensor nodes. Finally, we will compare our approach with SRSA, proposed by Tao WU et al., to show that the performance of our approach outperforms SRSA in terms of collision reduction, throughput and so on.

It has been proposed to use heavy ion beams with energies around 10 MeV/amu, masses around 200, and average charges of 1+ as a driver for inertial fusion reactor. Current designs require the beams to travel through a region where the background gas pressure is several milli-torr. Thus, it is important to assess the rate at which the charge state of an incident beam evolves while passing through the background gas. The first objective of this project is to study the dependence of cross sections for multi-electron loss on target atomic number by using 6 MeV/amu Xe18+ ions and to compare the results with the n-body Classical Trajectory Monte Carlo calculations. A secondary objective of this project is to determine the extent to which the cross sections for molecular targets can be represented as sum of the cross sections for their atomic constituents. Cross sections for loss of one through eight electrons from 6 MeV/amu Xe18+ in single collisions have been measured with noble gas targets. The target Z-dependence of the total loss cross section was found to be well represented by two straight line segments. The cross section for He and Ne define one straight line segment and those for Ar, Kr and Xe define the other, where exhibits a smaller slope. The predictions of n-CTMC calculations are in good agreement with the measured total electron loss cross sections. A semiempirical fitting procedure based on the independent electron approximation provided a reasonably good representation of the individual cross sections for all of the noble gas targets. Additional measurements performed with a variety of molecular targets provided a rigorous test of cross section additivity and showed that the additivity rule works well for electron loss from heavy ions in the present energy and charge regime. A semiempirical calculation based the IEA shows that the average most probable impact parameter for electron loss is much smaller than the target molecular bond length. This result is believed to account for the finding of the insensitivity of the electron loss cross section to molecular structure.

This thesis proposes the methodology and guidelines for community-based macro-level CPM transferability to do road safety planning applications, with models developed in one spatial-temporal region being capable of used in a different spatial-temporal region. In doing this. the macro-level CPMs developed for the Greater Vancouver Regional District (GVRD) by Lovegrove and Sayed (2006, 2007) was used in a model transferability study. Using those models from GVRD and data from Central Okanagan Regional District (CORD), in the Province of British Columbia. Canada. a transferability test has been conducted that involved recalibration of the 1996 GVRD models to Kelowna, in 2003 context. The case study was carried out in three parts. First, macro-level CPMs for the City of Kelowna were developed using 2003 data following the research by GVRD CPM development and use. Next, the 1996 GVRD models were recalibrated to see whether they could yield reliable prediction of the safety estimates for Kelowna, in 2003 context. Finally, a comparison between the results of Kelowna’s own developed models and the transferred models was conducted to determine which models yielded better results. The results of the transferability study revealed that macro-level CPM transferability was possible and no more complicated than micro-level CPM transferability. To facilitate the development of reliable community-based, macro-level collision prediction models, it was recommended that CPMs be transferred rather than developed from scratch whenever and wherever communities lack sufficient data of adequate quality. Therefore, the transferability guidelines in this research, together with their application in the case studies, have been offered as a contribution towards model transferability to do road safety planning applications, with models developed in one spatial-temporal region being capable of used in a different spatial-temporal region.

The main objective of this work was to understand fundamental processes related to incipient continental collision through studying the tectonostratigraphic evolution of Cyprus, in its Easternmost Mediterranean context. This was achieved by compiling structural, sedimentological and stratigraphic evidence from Late Cenozoic to Recent sequences, and by applying palaeomagnetic and luminescence methods of dating. In particular, the basin-fill of the Neogene basins provides a temporal and palaeogeographic control to interpret syn-depositional and post-depositional structural assemblages. Four neotectonic deformation phases are recognised. The Polis and Pissouri Basins originated as Tortonian depocentres in response to syn-depositional W-E/WSW-ENE D1 extension. The Maroni Basin originated as a Tortonian depocentre in response to syn-depositional NW-SE D1 extension. The difference in extension direction between west and south-central Cyprus is attributed to the curvature of the Cyprus Arc. The Middle - Late Pliocene D2 extensional/transtensional phase re-orientated the Neogene basins and resulted in syn-depositional NW-SE extension. A kinematic change occurred at ~3 Ma, attributed to the collision of the Eratosthenes Seamount with an active trench, the ‘Cyprus Arc’. Early Pleistocene to Recent D3a transpression generated strike-slip faulting along E-W trends, conjugate left-lateral NNE-SSW-trending and right-lateral NNW-SSE-trending strike-slip faults and reactivated Tortonian D1 NW-SE and NE-SW structures. Middle Pleistocene to Recent D3b compression produced intense NE-SW contractional deformation orientated along NW-SE trends. Optically stimulated luminescence (OSL) dating was used as a tool to constrain the D3a/D3b events, by generating a chronology for their associated sediments. D3 transtensional lineaments originated in the early Pleistocene (174.1 ± 20.9 ka < D3a < 76.6 ± 16.43 ka), and are still active today (Cape Kiti: 38.1 ± 13.2 ka < D3a < 12.1 ± 0.1 ka). D3 compressional lineaments originated in the middle Pleistocene, and were still actively growing at 76.8 ± 31.6 ka. To constrain the timing of regional uplift in south and central Cyprus, a magnetostratigraphy was generated for the Plio-Pleistocene units of the Pissouri and Mesaoria Basins. The results indicate that rapid uplift began in the latest Pliocene (c. 2.14 – 1.95 Ma), coincident with the large-scale progradation of Gilbert-type fan deltas into the Pissouri Basin, and the incursion of large fluvial networks into the Mesaoria Basin. In light of the new evidence, three alternative models for the Early Cenozoic to Recent tectonostratigraphic evolution of Cyprus are considered: model 1, subduction/incipient collision; model 2, advanced collision; and model 3, transpression. Some difficulties exist in detail, with all three models. However, at present the working hypothesis is as follows: areas to the east of Cyprus (Syria, S Turkey) were in a collisional setting from Mid-Miocene time onwards. Cyprus remained in an oceanic embayment (Levant Sea) further west and subduction continued during Miocene time. Compressional processes may have been active at depth during this time. Southward extension (trench roll-back) was taking place at a high structural level in S Cyprus, as with many other convergent margin settings (e.g. SW Peloponnese; Aleutians; Sunda arc). Subsequently, the collision of the Eratosthenes Seamount with the Cyprus Arc obstructed subduction and initiated rapid uplift of the Troodos Massif. The initial manifestation of this kinematic change was the generation of E-W-trending strike-slip faults and the development of conjugate left-lateral NNE-SSW-trending and right-lateral NNW-SSE-trending strike-slip faults. Transpression resulted in the reactivation of D1/D2 E-W, NE-SW and NW-SE structures. Subsequent deformation is documented in a compressional lineament in SW Cyprus. In addition, the over-riding plate in southwest Cyprus still appears to be undergoing gravity spreading outwards from the developing collision zone.

The visual environment of any animal is a complex amalgamation of sensory information (Lochmann and Deneve, 2011); however, it is adaptive for an animal to only react to salient cues (Zupanc, 2010). For many organisms, the detection of an approaching object, such as an oncoming conspecific or a predator, is particularly important. An approaching object with constant velocity is called looming, and has been widely studied for evoking avoidance behaviours in a number of animal species (Gibson, 1958). The migratory locust, Locusta migratoria, has been used extensively as a model system for visually guided behaviour, due to its robust collision-avoidance behaviours and its tractable nervous system (Schlotterer, 1977). The Lobula Giant Movement Detector (LGMD) and the Descending Contralateral Movement Detector (DCMD) constitute one pathway in the locust visual system that integrates the entire field of view that has been implicated in coordinating these types of behaviours (Santer et al., 2006). Previous studies have found that the LGMD/DCMD pathway responds to many visual stimuli, including complex scenes (Rind and Simmons, 1992), approaching paired objects (Guest and Gray, 2006), objects with compound shapes (Guest and Gray, 2006), and objects that follow compound trajectories (McMillan and Gray, 2012). These findings suggest that this pathway is capable of encoding complex motion such as exists in the locust’s natural environment. In my first objective (Chapter 2), I tested the response of the locust DCMD to increasingly complex motion. Using computer generated disks that followed compound trajectories with different velocities, I demonstrate that the DCMD is capable of encoding the location, trajectory, and velocity of an approaching object through aspects of the response profile over time. The motor systems of invertebrates are often controlled by ensembles of neurons working together (Dubuc et al., 2008; Hedrich et al., 2011; Gonzalez-Bellido et al., 2013). The locust visual system has at least five identified descending neurons, beyond the DCMD, that respond to visual motion (Rowell, 1971; Griss and Rowell, 1986; Gray et al., 2010). Due to the tractability of extracellular recordings of the DCMD, these neurons remain relatively little studied. Furthermore, their responses to stimuli have not been investigated concurrently. With recent advancements in multichannel recordings and spike sorting algorithms, it is now possible to explore the responses of multiple neurons in the locust system together. In my second objective (Chapter 3), I recorded from the connective of the locust using multichannel electrodes while challenging it with a wide array of visual stimuli. Preliminary results of these experiments identified as many as five neuronal units with distinctive firing patterns, some which appear to be novel. Together, these results illustrate that the locust visual system is more complex than previously thought, through both the abilities of a single neuron to encode many aspects of visual motion and the presence of multiple unique, visually-sensitive neurons.

This thesis discusses the theory and presents the numerical solution of the S-wave models of electron-hydrogen and electron-helium scattering. The Convergent Close-Coupling (CCC) method is used to obtain the numerical results. The focus within the electron-hydrogen S-wave model is to investigate cross section results for scattering from excited states; in particular, the elastic free-free transitions. These contain a divergent potential matrix element as the first term. The investigation of the electron-helium S-wave model is split into two sections, firstly applying the Frozen-Core approximation and then relaxing this approximation. This includes the first accurate ab initio calculation of double-excitation of helium.