The growth dynamics of technology-based firms in Scotland

In recent years high growth firms (HGFs) undertaking rapid, transformative growth, have been identified as important contributors to economic growth (Acs et al, 2008; Anyadike-Danes et al, 2009; OECD, 2010). For a wide variety of reasons, notably their contribution to employment growth, high export intensity, strong contribution to productivity growth and innovation, HGFs have been hailed as vital drivers of economic competitiveness (Henrekson and Johansson, 2010). As a consequence, these firms (often referred to as 'gazelles'), have been accorded a central role in many economic development strategies at both national and regional levels, especially during a time of economic austerity where employment growth has been an overriding policy goal for many governments (BERR, 2008; NESTA, 2011; OECD, 2010; Scottish Enterprise, 2011). Yet despite the strong policy focus on the promotion of HGFs in recent times, much remains unknown about these organisations and how best to support them (Henrekson and Johansson, 2010; Anyadike-Danes et al, 2012; Mason and Brown, forthcoming). Scottish Enterprise recently commissioned research on Scotland’s population of HGFs (Mason and Brown, 2010). This was the first comprehensive analysis of these firms ever conducted in Scotland and some of the findings were published in this journal (Brown and Mason, 2010). One of the most significant conclusions from this study was that they are extremely heterogeneous in terms of their age, size, ownership and industry sector. Few fit the stereotypical ‘gazelle’ definition which refers to young high growth firms that are less than five years old. The vast majority are over 10 years old, with some significantly older (Mason and Brown, 2010). Furthermore, only a relatively small proportion of these firms are in high-tech areas of the economy. According to some scholars, there is ‘no evidence that Gazelles are overrepresented in high- technology industries’ (Henrekson and Johansson, 2010, p.240). Despite their strong prioritisation by policy makers, the reality is that the representation of technology based firms (TBFs) in the population of HGFs is roughly on a par with their proportion in the economy (Mason and Brown, forthcoming). In view of these twin priorities of promoting high growth in general and high tech firms in particular, Scottish Enterprise commissioned further research to explore HGFs, especially in high tech areas of the economy. The objectives of this paper are twofold: to provide an update on the level of HGFs in Scotland and to assess the population of TBFs in Scotland. The paper proceeds as follows. First, the terms high growth and technology-based enterprises are defined. Second, the methodology is outlined. Third, the aggregate evidence on the levels of HGFs in Scotland is presented. Fourth, the population of TBFs in Scotland, including analysis of high growth TBFs is profiled. Fifth, some of the key characteristics of high growth TBFs in Scotland are examined. Sixth, some of features of these firms which were captured during the qualitative part of this research process are summarised. The paper finishes with some brief conclusions and issues for further research

Geophysical investigation and assessment of the Rye Patch Known Geothermal Resource Area, Rye Patch, Nevada

A gravity and ground-based magnetic survey was conducted at the Rye Patch Known Geothermal Resource Area located at Rye Patch, Nevada. The purpose of the study was to attempt to further delineate the geothermal reservoir and/or to identify potential drilling targets. The survey consisted of collecting data at 264 new stations to augment data from 203 stations collected in 2008. Information from previous seismic, aeromagnetic and geochemical investigations was also examined and incorporated. Filtering methods including removal of a polynomial trend surface and wavelength filtering were utilized on the gravity data to remove the strong regional overprint caused by the large density contrast between the low density alluvium within the valley versus the near-surface higher density rock in the higher elevations. After filtering, the Rye Patch Fault, the Range Front Fault, an eastwest trending feature at the location of “southeast” fault, and another possible fault at the southern end of the study area are observable in the Rye Patch geothermal anomaly area. In the Humboldt House anomaly area, the northeast trending features identified by MacNight et al. (2005) and Ellis (2011) are not discernable although there is a significant gravity low in this area. Based on estimates arrived at by using 2 derivative methods, fault dip angles are on the order of 80 and are nd oconsistent with previous conceptual models of the site. Computer modelingindicates that the fault blocks may also be rotated back to the east. Due to errors in collecting diurnal information, the ground-based magnetic information was of limited use. Anomalies identified with the magnetic data do however correlate with the locations of anomalies identified using gravity and aeromagnetic surveys. Results indicate that gravity methods can be an effective method of defining approximate fault locations, lengths, and approximate trends and dip angles

Development of numerical and data models for the support of digital twins in offshore wind engineering

Error on title page. Date of award is 2022.As offshore wind farms grow there is a continued demand for reduced costs. Maintenance costs and downtime can be reduced through greater information on the asset in relation to its operational loads and structural resistance to damage and so there is an increasing interest in digital twin technologies. Through digital twins, an operational asset can be replicated computationally, thus providing more information. Modelling these aspects requires a wide variety of models in different fields. To advance the feasibility of digital twin technology this thesis aims to develop the multi-disciplinary set of modelling domains which help form the basis of future digital twins. Throughout this work, results have been validated against operational data recorded from sensors on offshore structures. This has provided value and confidence to the results as it shows how well the mix of state-of-the art models compare to real world engineering systems. This research presents a portfolio of five research areas which have been published in a mix of peer-reviewed journal articles and conference papers. These areas are: 1) A computational fluid dynamics (CFD) model of an offshore wind farm conducted using a modified solver in the opensource software. This work implements actuator disk turbine models and uses Reynolds averaged Naiver Stokes approaches to represent the turbulence. This investigates the impact of modelling choices and demonstrates the impact of varied model parameters. The results are compared to operational site data and the modelling errors are quantified. There is good agreement between the models and site data. 2) An expansion on traditional CFD approaches through incorporating machine learning (ML). These ML models are used to approximate the results of the CFD and thereby allow for further analysis which retains the fidelity of CFD at comparatively negligible computational cost. The results are compared to operational site data and the errors at each step are quantified for validation. 3) A time-series forecasting of weather variables based on past measured data. A novel approach for forecasting time-series is developed and compared to two existing methods: Markov-Chains and Gradient Boosting. While this new method is more complex and requires more time to train, it has the desirable feature of incorporating seasonality at multiple timescales and thus providing a more representative time-series. 4) An investigation of the change in modal parameters in an offshore wind jacket structure from damages or from changing operational conditions. In this work the detailed design model of the structure from Ramboll is used. This section relates the measurable modal parameters to the operational condition through a modelling approach. 5) A study conducted using accelerometer data from an Offshore Substation located in a wind farm site. Operational data from 12 accelerometers is used to investigate the efficacy of several potential sensor layouts and therefore to quantify the consequence of placement decisions. The results of these developments are an overall improvement in the modelling approaches necessary towards the realisation of digital twins as well as useful development in each of the component areas. Both areas related to wind loading as well as structural dynamics have been related to operational data. The validation of this link between the measured and the modelled domains facilitates operators and those in maintenance in gaining more information and greater insights into the conditions of their assets.As offshore wind farms grow there is a continued demand for reduced costs. Maintenance costs and downtime can be reduced through greater information on the asset in relation to its operational loads and structural resistance to damage and so there is an increasing interest in digital twin technologies. Through digital twins, an operational asset can be replicated computationally, thus providing more information. Modelling these aspects requires a wide variety of models in different fields. To advance the feasibility of digital twin technology this thesis aims to develop the multi-disciplinary set of modelling domains which help form the basis of future digital twins. Throughout this work, results have been validated against operational data recorded from sensors on offshore structures. This has provided value and confidence to the results as it shows how well the mix of state-of-the art models compare to real world engineering systems. This research presents a portfolio of five research areas which have been published in a mix of peer-reviewed journal articles and conference papers. These areas are: 1) A computational fluid dynamics (CFD) model of an offshore wind farm conducted using a modified solver in the opensource software. This work implements actuator disk turbine models and uses Reynolds averaged Naiver Stokes approaches to represent the turbulence. This investigates the impact of modelling choices and demonstrates the impact of varied model parameters. The results are compared to operational site data and the modelling errors are quantified. There is good agreement between the models and site data. 2) An expansion on traditional CFD approaches through incorporating machine learning (ML). These ML models are used to approximate the results of the CFD and thereby allow for further analysis which retains the fidelity of CFD at comparatively negligible computational cost. The results are compared to operational site data and the errors at each step are quantified for validation. 3) A time-series forecasting of weather variables based on past measured data. A novel approach for forecasting time-series is developed and compared to two existing methods: Markov-Chains and Gradient Boosting. While this new method is more complex and requires more time to train, it has the desirable feature of incorporating seasonality at multiple timescales and thus providing a more representative time-series. 4) An investigation of the change in modal parameters in an offshore wind jacket structure from damages or from changing operational conditions. In this work the detailed design model of the structure from Ramboll is used. This section relates the measurable modal parameters to the operational condition through a modelling approach. 5) A study conducted using accelerometer data from an Offshore Substation located in a wind farm site. Operational data from 12 accelerometers is used to investigate the efficacy of several potential sensor layouts and therefore to quantify the consequence of placement decisions. The results of these developments are an overall improvement in the modelling approaches necessary towards the realisation of digital twins as well as useful development in each of the component areas. Both areas related to wind loading as well as structural dynamics have been related to operational data. The validation of this link between the measured and the modelled domains facilitates operators and those in maintenance in gaining more information and greater insights into the conditions of their assets

The Stock of External Sovereign Debt: Can We Take the Data At ‘Face Value’?

The stock of sovereign debt is typically measured at face value. This is a misleading indicator when debts are issued with different contractual forms. In this paper we construct a new measure of the stock of external sovereign debt for 100 developing countries from 1979 to 2006 that is invariant to contractual form, and illustrate five problems with debt stocks measured at face value. First, we show that correcting for differences in the contractual form of debt paints a very different quantitative, and in some cases also qualitative, picture of the stock of developing country external sovereign debt. Second, rankings of indebtedness across countries, which were historically used to define eligibility for debt forgiveness, are sometimes inverted once we correct for differences in contractual form. Third, the empirical performance of the benchmark quantitative model of sovereign debt deteriorates by between 40 to 70 percent once model-consistent measures of debt are used. Fourth, we show how the spread of aggregation clauses in debt contracts which award creditors voting power in proportion to the contractual face value may introduce inefficiencies into the process of restructuring sovereign debts. Fifth, we show how the use of contractual face values gives issuing countries the ability to manipulate their debt stock data, and illustrate the use of these techniques in practice.

Bait Stations for Controlling Voles in Apple Orchards

Bait stations made with polyvinylchloride (PVC) pipe were compared with hand-broadcast applications of rodenticides for achieving long-term control of pine and meadow vole populations (Microtus pinetorum and M. pennsylvanicus, respectively) in two apple orchards in the mid-Hudson Valley of New York. The stations were constructed of three pieces of 1.5-in diameter PVC tubing joined together in the shape of an inverted T . Roofing shingles were placed over the entrances to some of the bait stations to encourage use by voles, while others were left uncovered. All stations were tied to trees, with no attempt to place them near runways or burrow entrances. Both pine and meadow voles consumed bait from the stations, regardless of whether the entrances were covered with roofing shingles. However, plugging of entrances with dirt was prevalent during winter in stations with roofing shingles. Vole activity and capture success were consistently lower on the plots with the two types of bait stations than on either the control or broadcast baiting plots 13, 26, 39, and 52 wk posttreatment, although the differences were not statistically different (p \u3e 0.05). The best control was achieved during the winter and early spring. Although spoilage of bait due to high humidity may limit its effectiveness in Eastern New York during the late spring and summer, the inverted T bait station provides a practical means of controlling voles in apple orchards during winter and early spring

Feasibility for damage identification in offshore wind jacket structures through monitoring of global structural dynamics

The modal response of a four-legged jacket structure to damages are explored and resulting considerations for damage detection are discussed. A finite element model of the Wikinger (Iberdrola) jacket structure is used to investigate damage detection. Damages, such as cracks, scour, corrosion and more, are modelled in a simulation environment. The resulting modal parameters are calculated, these parameters are compared to those from an unaltered structure and metrics are calculated including frequency change, modal assurance criterion and modal flexibility. A highly detailed design-model is used to conduct a sensitivity study on modal parameters for a range of changes. By conducting this on the same structure, this acts as a useful reference for those interested in the dynamic response of offshore wind jacket structures. Additionally, this paper addresses the issue of changes in mode parameters resulting from turbine yaw. This paper also considers the challenge of mode-swapping in semi-symmetric structures and proposes several approaches for addressing this. Damage typically results in a reduction of frequency and change in mode shapes, but in ways which can be distinguished from other structural changes, given the extent of this model. These findings are important considerations for modal-based damage detection of offshore wind support structures

Comparison of Methods for Detecting Voles under Apple Trees

We conducted a study in 2 heavily infested orchards in the mid-Hudson Valley of New York to evaluate methods for detecting the presence of meadow voles (MV, Microtus pennsylvanicus) and pine voles (PV, M. pinetorum) under apple trees. We quantified several possible signs indicating the presence of voles in each of the 4 quadrants under the canopy of each tree, and then set and monitored traps until capture success in the orchard declined to zero. There was no evidence that the 4 quadrants differed with respect to any of the variables examined. The apple slice index (ASI) was the best indicator for both species. Detection improved significantly (P \u3c 0.05) when the ASI was used in conjunction with the number of runways (MV) or tunnels (PV) under the tree, although neither of the latter 2 signs was by itself a reliable indicator. The ASI and search for runways and tunnels should be conducted in at least 2 quadrants under each tree. The significance of these findings for managing voles in apple orchards is discussed

Country town growth in South-eastern Australia : three regional studies, 1861-1891

Australia’s galloping urbanization was the major feature of settlement in the second half of the nineteenth century, and - then as now - its outstanding characteristic was the dominant role of metropolization in this process. The fifties were a time of formative upsets to the pattern of settlement in Victoria, and, to a lesser extent, in New South Wales, and the nineties again saw a temporary disruption in the trend of urbanization in each colony. The generation from 1861 to 1891 was relatively free of such upsets, and this study addresses the question of urbanization in that period, focussing particularly on the country towns, focussing, that is, on the reverse of the urban coin of which the Australian metropolis is so manifestly the obverse. The retardation of provincial towns has made relics of many of them; but although to gaze on the streets of many such towns is to gaze on the nineteenth century, they have commanded little scholarly attention. As an introduction, then, Chapter One contrasts nineteenth century awareness of urbanization (and denigration of country towns) with the delay in professional attention to the subject, and sketches the approach made in this study. In particular, the lack of previous studies has conditioned a concentration on the basic question of country town growth. Chapter Two, having defined 'country towns', is concerned with determining, in a broad way, the role of country towns in south-eastern Australia in the process of urbanization during this period. Two main facts emerge: the country towns as a body did not grow as strongly as Sydney and Melbourne; and the country towns of New South Wales, as a body and individually, grew more strongly than the Victorian towns. This, then, was what happened, and Chapters Three to Nine are directed towards finding out why. To do this, the history of three country towns and their hinterlands have been studied, namely, Creswick, a Victorian gold-mining town near Ballarat, Hamilton, a pastoral town in the Western District of Victoria, and Wagga, a pastoral and agricultural town in the Riverina district of New South Wales. The factors in town growth have been examined at three levels; Chapters Three to Five look at the internal aspects of town growth, Chapters Six to Eight at its regional aspects, and Chapter Nine discusses the role of the State. Chapter Three, which is chiefly demographic, analyses the components of growth by looking separately at various elements in the population, such as changing sex ratios and workforce proportions, in order to gain an idea of the extent to which growth itself, and fluctuations in growth, derived simply from necessary demographic adjustments. The question of the contribution of migration to population growth is also discussed, since even the growing towns had begun to experience net out-migration by the end of the period. Chapter Four first briefly examines the location and the circumstances of the foundation of each town, seeking implications for future growth. It then considers the manner in which each town was actually settled, and by whom, through an analysis of the alienation of Crown lots. Finally, the quality and quantity of residential construction in the towns are examined in the light of available building materials, and of the quality of housing in the towns' rural hinterlands. The concept of regionality is introduced, and differences between the towns in each colony elucidated. In Chapter Five, the general occupational structure of each town - for which the materials are unsatisfactory after 1871 - is first noted, both generally and in terms of the basic-nonbasic concept. The discussion of economic functions is continued with separate considerations of the place of primary industry (as an element of the town's own workforce, not as a general regional factor), secondary industry, and tertiary industry in town growth. Non-economic functions, both basic and nonbasic, are also discussed, although they illuminate the quality of life and the nature of regionality, rather than the question of population growth. Chapters Six to Eight examine, in turn, each of the rural hinterlands of the sample towns, to determine their relative propensities to town growth, and to elucidate the towns' regional roles. Chapter Six is prefaced by a discussion of the demographic bases of regionality and urbanism, in which it is shown that towns had greater affinities with their respective regions than with other towns. In each chapter, three main questions are considered in their relevance to town growth: rural land use; the pattern of settlement in terms of the size of rural holdings and the accretion or fragmentation of 'urban' services; and the development of transport, especially the role of the railway. In each chapter, the emphasis given to each of these sections varies according to the requirements of each case. Chapter Six concentrates particularly on the unusual diversification of land use in Creswick Shire, the decline of agriculture and the revival of mining. The density of settlement in the Shire, and the public fragmentation of urban services, are examined, as is the effect of the railway on the town's life. Chapter Seven deals briefly with the unrelieved pastoralism and sparse population of Dundas Shire, and shows that in the accretion of functions, Hamilton was able to gain more from its hinterland population than the others from theirs. The association of townsmen in agitating for railway extension is discussed, as well as the apparent effects of the railway on the town's functions. Chapter Eight first traces the changes in land use in the Murrumbidgee Electorate in this period, noting especially the wheat-growing boom which followed the advent of the railway; it notes, too, Wagga's function in the handling and fattening of stock driven from distant parts. The successions and patterns of settlement in the district are then studied in their relation to town growth, and the early transport lines and the course and effects of railway extension are dealt with. The dependence of towns on their respective regions having been established, Chapter Nine outlines the direct and indirect ways in which towns relied on the State. Certain differences between the colonies are suggested, and the general limitations on local municipal government, and on the avenues of approach to the State by the towns, are stated. The extent and effects of reliance on the State are tentatively assessed

Small molecules induce mesocrystal formation: nanoparticle aggregation directed by self-assembling calixarenes

Calixarenes have been shown to induce mesocrystal formation of barium sulfate, despite being relatively low molecular weight additives. Scanning probe microscopy has shown that a possible mechanism is the self-assembling properties of the calixarene resulting in steric stabilization of the nanoparticles, comparable to that typically requiring polymeric additives