The determination of subtle deformation signals using a permanent CGPS network in the Aegean

Geophysical motions can occur over a broad temporal spectrum, from high frequency seismic movements to very long period tectonic deformation. The Aegean region is tectonically one of the most active areas on Earth. There have, over the past 15 years, been a range of campaign style GPS studies which have looked to increase our knowledge of the area and better define the geodynamic processes involved. In 2002 the Center for the Observation and Modelling of Earthquakes and Tectonics (COMET) established a network of continuously operating GPS receivers (CGPS) throughout the region in order to add to the knowledge gained from previous studies. This thesis focuses on which tectonic motions can be observed using the COMET continuous GPS network. Approaches for the precise analytical estimation of subtle tectonic motion are presented. Daily coordinate estimates of COMET sites and a number of ITRF (International Terrestrial Reference Frame) sites around Europe were calculated using a precise point positioning strategy and ambiguity resolution using NASA’s GIPSY – OASIS II processing software and IGS (International GPS Service) precise products. Time series produced showed post fit standard deviations of 2-3 mm in the horizontal and 6-8 mm in the vertical. Significant annual periodic variation is observed in the time series. The coordinate time series studies were further refined using a selection of filters. Firstly, gross and sigma filters were applied to remove outliers, the data then had a range of regional filters applied looking to best define and remove the common mode error in the area. These filters produced mixed results with time series improvement occurring on a site by site basis. In some cases noise was reduced by a factor of 2 whilst in other cases there was little or no improvement. This combined with a lack of knowledge of the individual site movements led to the use of a filtered baseline method, whereby common mode error was removed purely on a site by site basis. This method revealed expansion across the Hellenic arc of the order of a few millimetres per year and sub millimetre north-south compaction behind the arc. It also revealed first evidence of transient motion at a number of sites parallel to the Hellenic arc. The transient signals occurred every 12 months ±1.5 and lasting for 40 – 100 days. These signals were not so much a reversal of tectonic motion akin to the silent earthquakes observed in Cascadia, Japan and Mexico, instead they appeared more as a pause in the otherwise consistent movement of the Aegean microplate overriding the subducting African lithosphere. In addition to the observed tectonic signals, the effects and implications of the two post processing strategies are analysed and discussed. Higher temporal frequency positioning is carried out on seismic events (Mw 6.7 earthquake Kithera, Mw 8.1 and Mw 6.7 earthquakes, Macquarie island) using instantaneous positioning followed by “sidereal filtering” whereby integer-cycle phase ambiguities are resolved using only single epochs of dual frequency phase and pseudorange data. These positions are then siderealy stacked to reduce the effects of geometry related error. The technique reduces geometry related noise by a factor ≈2 using epoch by epoch 30 second data. The feasibility of the technique for observing pre, co and post seismic signals is demonstrated. A visualisation tool was developed to allow the simultaneous observation of the tectonic motion of a CGPS network data over any spatial and temporal regimes

Quantitative Techniques in Participatory Forest Management

Forest management has evolved from a mercantilist view to a multi-functional one that integrates economic, social, and ecological aspects. However, the issue of sustainability is not yet resolved. Quantitative Techniques in Participatory Forest Management brings together global research in three areas of application: inventory of the forest variables that determine the main environmental indices, description and design of new environmental indices, and the application of sustainability indices for regional implementations. All these quantitative techniques create the basis for the development of scientific methodologies of participatory sustainable forest management

Quantitative Techniques in Participatory Forest Management

Forest management has evolved from a mercantilist view to a multi-functional one that integrates economic, social, and ecological aspects. However, the issue of sustainability is not yet resolved. Quantitative Techniques in Participatory Forest Management brings together global research in three areas of application: inventory of the forest variables that determine the main environmental indices, description and design of new environmental indices, and the application of sustainability indices for regional implementations. All these quantitative techniques create the basis for the development of scientific methodologies of participatory sustainable forest management

Evolution of a Sandur : sixty years of change, Skeiºarársandur, Iceland

PhD ThesisGlaciers are a major component of the global climate system, adjusting to changes in climate over a range of timescales. Knowledge of the dynamics of contemporary glaciated landscapes will allow accurate reconstruction of glacier margin fluctuations within the landform and sedimentary record as well as predictions of the response of ice-marginal landscapes to future glacier margin fluctuations. Existing models of ice-marginal, proglacial landscape evolution focus primarily on landforms generated in response to single, relatively short-lived, highmagnitude large-scale events such as glacier surges or glacier outburst floods (jökulhlaups). Observations of these events have frequently been restricted to short time windows (days to several years) or inferred from stratigraphic sections and are therefore subject to misinterpretation. Relatively little research has been undertaken on the development of icemarginal and proglacial landscapes over decadal time-scales (101-102 years). This study examines the controls on the evolution of the ice-marginal landscape of Skeiðarárjökull over a decadal timescale. Skeiðarárjökull is a temperate, surge-type, piedmont outlet glacier located in south-east Iceland. Skeiðarárjökull, and its outwash plain Skeiðarársandur, have been subject to numerous surges and jökulhlaups and post-depositional modification due to the melt out of buried glacier ice, providing a valuable modern process-form analogue for landscape evolution at Pleistocene ice sheet margins. Digital Elevation Models (DEMs) were extracted from the aerial photographs taken at intervals over the past six decades to quantify the rate of landscape change over decadal time periods. This data, when combined with observations from aerial photographs of numerous suites of large-scale sub- and englacial features exposed by the glacier's recession permits models of the long-term response of proglacial regions to surges, jökulhlaups and glacier margin recession to be tested. This study developed a holistic model to describe the interdependence of glacier margin fluctuations, jökulhlaups and post-depositional modification and their impact on sandur evolution.NER

Aeolian dune development and evolution on a macro-tidal coast with a complex wind regime, Lincolnshire coast, UK

Coastal foredunes are natural aeolian bedforms located landward of the backshore and which interact continuously with the beach. Traditionally, coastal dunes have been associated with onshore winds, however they can be found under more complex wind regimes where offshore winds are common such as the UK East coast, Northern Ireland and New Zealand. This research investigates the ways in which foredune-beach interactions occur under a complex wind regime at a range of overlapping temporal and spatial scales and is innovative in that it explicitly links small-scale processes and morphodynamic behaviour to large scale and long-term dynamics. The study area is the north Lincolnshire coast, East England. Detailed observations of airflow at three locations under varying wind regimes revealed considerable spatial variations in wind velocity and direction, however it was possible to determine a general model of how foredune topography deflected and modified airflow and the resultant geomorphological implications (i.e. erosion and deposition). During direct offshore and onshore winds, airflow remained attached and undeflected; and distinct zones of flow deceleration and acceleration could be identified. During oblique winds airflow was deflected to become more parallel to the dune crest. The field sites used are characterized by a seasonal erosion/accretion cycle and a series of increasingly complex models was developed and tested to determine whether it was possible to predict sand volume changes in the foredune-beach system based on a limited number of variables. The model predictions were tested against detailed digital terrain models at a seasonal timescale. The model prediction that best matched the observed (surveyed) sand volume changes included wind speed, direction, grain size, fetch effect controlled by beach inundation and angle of wind approach was accurate to within ±10% for 18 out of 48 tests at the seasonal scale and 6 out of 12 tests over periods of >5 years. A key variable influencing foredune-beach sand volume is the magnitude and frequency of storm surge events and this was not factored in to the model, but may explain the model-observation mismatch over the medium-term on two occasions. Over the past 120 years historical maps and aerial photographs indicate long-term foredune accretion of approximately 2 m year-1 at the three study sites (1891-2010). At this timescale, rates of coastal foredune accretion reflect the low occurrence of severe storm surges and suggest rapid post-storm recovery. The morphological response of the foredune-beach morphology is considered to be a combination of controlling and forcing factors. Process-responses within the system, associated with nearshore interactions and sediment transfer from the littoral drift, are compiled into a multi-scale morphodynamic model. Important to match appropriate dataset to scale of research question or management plan being explored. In the case of management, long-term records of past activity are necessary to predict the future but also to understand natural responses of system to short-term impact such as storm surge

Simulating academic entrepreneurship and inter-organisational collaboration in university ecosystems, a hybrid system dynamics agent-based simulation

Universities are increasingly expected to actively contribute to socio-economic development. Academic entrepreneurship and the evolution of the entrepreneurial university within ecosystems have received increasing attention from both policymakers and academic communities over the last decades. However, most studies on universities' external engagement have focused on individual activities and single universities, hereby neglecting the feedback effects between different activities and how universities are linked through an overlap of their ecosystems. The result is an incomplete understanding of how universities interact with their ecosystem and the resulting inter- and intra-organisational dynamics. This research addresses this issue by developing a hybrid system dynamics agent-based model, which captures feedback structure and the internal decision-making of universities and companies. Both the conceptual and simulation model are based on a triangulation of the literature, interviews with representatives of Scottish universities, and secondary data for Scottish universities and UK businesses. This research makes several theoretical, methodological, and empirical contributions. From a theoretical perspective, it contributes in two distinct ways to the field of entrepreneurship by defining university ecosystems in new way that provides a basis for future research and developing a multi-modal simulation model that can be applied in tested in different contexts. The methodological contributions to the field of modelling and simulation in management science include a modelling process for hybrid simulations, new practices for modelling the size of agent populations through different designs of stocks and flows in the system dynamics module in hybrid simulations, and complex events for recognising emergent behaviour. Lastly, this research makes two empirical contributions to the field of entrepreneurship. This research shines a light on the dynamics of academic entrepreneurship and how universities can partially overcome a low research prestige to increase academic entrepreneurship. Implications for policy and practice are outlined and opportunities for future research conclude this thesis.Universities are increasingly expected to actively contribute to socio-economic development. Academic entrepreneurship and the evolution of the entrepreneurial university within ecosystems have received increasing attention from both policymakers and academic communities over the last decades. However, most studies on universities' external engagement have focused on individual activities and single universities, hereby neglecting the feedback effects between different activities and how universities are linked through an overlap of their ecosystems. The result is an incomplete understanding of how universities interact with their ecosystem and the resulting inter- and intra-organisational dynamics. This research addresses this issue by developing a hybrid system dynamics agent-based model, which captures feedback structure and the internal decision-making of universities and companies. Both the conceptual and simulation model are based on a triangulation of the literature, interviews with representatives of Scottish universities, and secondary data for Scottish universities and UK businesses. This research makes several theoretical, methodological, and empirical contributions. From a theoretical perspective, it contributes in two distinct ways to the field of entrepreneurship by defining university ecosystems in new way that provides a basis for future research and developing a multi-modal simulation model that can be applied in tested in different contexts. The methodological contributions to the field of modelling and simulation in management science include a modelling process for hybrid simulations, new practices for modelling the size of agent populations through different designs of stocks and flows in the system dynamics module in hybrid simulations, and complex events for recognising emergent behaviour. Lastly, this research makes two empirical contributions to the field of entrepreneurship. This research shines a light on the dynamics of academic entrepreneurship and how universities can partially overcome a low research prestige to increase academic entrepreneurship. Implications for policy and practice are outlined and opportunities for future research conclude this thesis

Aerial Vehicles

This book contains 35 chapters written by experts in developing techniques for making aerial vehicles more intelligent, more reliable, more flexible in use, and safer in operation.It will also serve as an inspiration for further improvement of the design and application of aeral vehicles. The advanced techniques and research described here may also be applicable to other high-tech areas such as robotics, avionics, vetronics, and space

The cartographic design and usability of whole-network bus maps

This study represents an investigation into understanding the variation in bus map design and the impact of map design preferences in public transportation information portrayal. In many cities, bus services represent a vital facet of easing traffic congestion and reducing pollution. However, with the entrenched car culture in many countries, including Malaysia, the country targeted here, persuading people to change their mode of transport is a significant challenge. To promote this modal shift, people need to know what services are available and where (and when) they go. Bus service maps provide an invaluable element of providing suitable public transport information, but are often overlooked by transport planners, and are under-researched by cartographers. Although bus services are ubiquitous, much more attention has been devoted to metropolitan rail network maps (e.g. Ovenden 2003 & 2015, Roberts, 2012). The earlier part of this study focuses on identifying the cartographic considerations when designing a bus map in a specific context. There are various approaches to the design of bus maps. It is a challenge for the authorities to understand which designs are preferred by the public and which perform best in conveying the required information. Even a quick look at a small sample of bus maps will show that there can be a significant variation in approach. This can vary from whole-network maps to single routes, and from geographically accurate maps to highly schematised representations. To advance the study and understand the cartographic styles of bus maps, it is necessary to develop a robust classification system that considers the critical factors in their design. The method employed was to examine a wide range of bus map examples from around the world, supplemented by considerations of other map classification systems and personal understanding of available options. The resulting classification is multi-faceted, but there are some apparent top-level differences in approach. One main distinction is between Geographical Approach maps and Schematic maps. While schematic maps are extensively used for metro systems, there are quite different considerations for bus maps and while some level of schematisation may be useful, highly schematic bus maps often present difficulties in everyday use. While the earlier research phases identified the significant options in bus map design, to inform design choices, it is also essential to consider what users prefer and best promotes successful use. To help provide guidance, a map usability study was conducted during which bus users and potential bus users had to solve several journey planning tasks using two different designs of whole-network bus maps. The two different designs are the Geographical Approach bus map design and the Semi-schematised bus map design. The distinguishing aspect of these two bus maps is only in their overall map design approach. Both maps have an identical bus route and bus information detail together with the same cartographic representation in terms of classification, symbolisation and typography. While many of the findings have general relevance to all bus map use situations, the usability testing was carried out in Malaysia to ensure the findings were relevant to promoting bus use in that country. 100 respondents were involved in the map usability test. Cultural differences can be a factor in influencing map use performance and design preferences. The outcomes of the usability study were analysed statistically, starting with descriptive statistical analysis of all possible influencing factors of map preferences (independent variable data) like age, gender, travel habits, driving license availability, among others. These data were then cross-analysed with the findings from the map usability test, ranging from the respondent performance based on the correctness of an answer to their opinions about the maps. The analysis includes the ease of use while using the map, the confidence level in using the map and their map design preference. The results show that the respondents prefer to use the Semi-schematised bus map design rather than the Geographical Approach bus map design. Their map preference’s selection is well explained by their performance in the journey-planning tasks and subsequent answers to the questionnaire. The Semi-schematic design had a higher degree of task correctness than when using the Geographical Approach design. This degree of correctness that favours semi-schematic design shows the same pattern across all genders, ages, and travel habits, and is decisively supported by the confidence level ratings and ease of map use ratings. Interestingly, respondents across all age groups say they would be willing to make greater use of public transport if there were more of these kinds of maps available. In conclusion, this research has brought much-needed insight into the public transport information provision of Malaysia’s public transport systems. There has been lack of research in this field in Malaysia, and the findings from this study have highlighted the benefit of using the right cartographic technique to enhance public transport information provision and improve the use of the public transport system as a whole. Apart from the continuous improvement in physical aspects of public transport systems, a well-designed public transport map that balances the efficient cartographic technique with local cultural preferences. All these measures certainly can help authorities and public transport providers in encouraging the modal shift from the regular use of private cars to more frequent use of public transport systems