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The strategic planning practices of small to medium enterprises in the food and beverages manufacturing sector in South Africa
Get PDFThis thesis examines the strategic planning practices of small to medium enterprises
(SMEs), to establish how SMEs can be better enabled to practice strategic planning. The
aim of this study is to use a qualitative approach to elaborate on the practice of strategic
planning by SMEs in South Africa.
Existing literature on the practices of strategic planning by SMEs in general and in the
food and beverages manufacturing sector in South Africa was reviewed and synthesised.
The synthesis informed the development of a theoretical strategic planning framework
to frame the empirical study.
The research followed the case study method and nine case studies were identified for
the main empirical study using theoretical sampling. There were at least three case
studies under each of the SME development stages on (i) very small, (ii) small and (iii)
medium enterprises. The use of case studies enabled the collection of data through in depth interviews, observations and archival documents from the identified case studies.
A pilot study was conducted to test, refine and improve the data collection and
respective data analysis.
The research established that majority of the SMEs (i) lack an appreciation of the
benefits of practicing strategic planning and having a strategy, (ii) they also do not have
the strategic management knowledge and skills to facilitate the practice of strategic
planning on their own; The study further established (iii) why SMEs do not practice
strategic planning and instead focus more on operational planning to achieve their short term goals and objectives, and (iv) highlighted challenges SMEs face in accessing
support available in South Africa.
The research contributes to knowledge on the practice of strategic planning by SMEs in
South Africa. This is achieved through (i) the provision of a proposed strategic planning
framework that SMEs can use to improve their practice of strategic planning (ii)
provision of an accompanying guideline that SMEs can use to better understand how to
use the proposed framework and (iii) a theoretical definition of strategy to standardise
the view of strategy by SMEs utilising the proposed strategic planning framework
Dual-comb distance metrology for industrial applications
Get PDFThis thesis describes the development of dual-comb metrology for industrial applications.
A simple, dual-comb system was developed for use in metrology. The system was comprised of two saturable absorption modelocked Er:fibre lasers. The lasers’ optical spectra
were centred at 1553.8 nm and 1551.3 nm. Both lasers had a repetition frequency of
78.87 MHz though one laser was tuneable over 400 kHz. The lasers were constucted with
polarisation-maintaining fibres for environmental robustness so that they would perform
well in industrial environments. Each laser output was coupled into a two-stage Er:fibre
amplifier. The maximum powers after amplification were 69.3 mW and 37.7mW. The
fibres of the lasers were co-spooled so that they would experience the same environment.
Measurement of the free-running repetition frequencies confirmed the repetition frequencies, although independent, were coarsely drifting together. This allowed locking of the
difference in the repetition frequencies to a stable value. The locking loop had an rms
phase variation of 0.0535 rad over the 2 s measurement time. Construction, characterisation and stabilisation of the dual-comb system is reported in Chapter 3.
The dual-comb system was used to demonstrate dual-comb time-of-flight metrology. Typically, data analysis of the interferograms collected in dual-comb time-of-flight
metrology involves taking the Hilbert transform of each interferorgram to derive their envelopes, then fitting a Gaussian to each envelope to determine their centre points in time.
The free-running combs caused the carrier frequency of the interferograms to vary from
DC to frep/2, such that the Hilbert transform did not always accurately derive the envelopes
of the interferograms. In response, a novel detection technique named Two-Photon Detection (2PD) was developed to detect the optical cross-correlation of two pulses arriving
at the detector simultaneously. This novel detection technique allowed the development
of a new metrology technique, carrier-free dual-comb time-of-flight metrology with two-photon detection. There were a number of advantages to the technique. Firstly, the direct
detection of the envelopes simplified the data analysis process as it removed the need
for Hilbert transforms. Secondly, the signal was carrier frequency insensitive and so did
not require locking of the comb carrier envelope-offset frequencies, simplifying the requirements on the dual-comb system. A third advantage was that, since the pulses were
collected without optically interfering, the combs did not need to operate at the same
wavelength, further simplifying the requirements on the dual-comb system. Finally, the
2PD envelopes, being carrier frequency insensitive, were unrestricted by the aliasing limit. The concept was supported by Matlab simulations and experimental demonstrations reported on in Chapter 4.
Demonstrations of carrier-free dual-comb time-of-flight metrology with two-photon
detection are presented in Chapter 4. The technique was demonstrated at a measurement
rate of 4 kHZ, exceeding by 2.4 times the limit of 1.7 kHz imposed by aliasing on traditional dual-comb metrology. An Allan deviation was recorded to quantify the precision
of the technique. For the minimum acquisition time of 250 µs (set by the 4 kHz measurement rate) the measurement precision was 17.8 µm. The precision scaled as the square
root of the number of measurements, reaching sub-µm precisions for 0.1 s of averaging.
After 1 s of averaging, the precision reached 150 nm which would be sufficient to hand
over the measurement to interferometry with a HeNe laser. After 2 s of averaging, the precision reached 93 nm which is below the 10−7 uncertainty limit imposed by atmospheric
fluctuations
Multi-population mortality modeling fitting, forecasting, comparison and application
Get PDFWe review a number of multi-population mortality models including several variations of the Li and Lee (2005) model, and the common-age-effect (CAE) model of
Kleinow (2014). Model parameters are estimated using maximum likelihood. Although this introduces some challenging identifiability problems and complicates the
estimation process, it allows a fair comparison of the different models. We propose
to solve these identifiability problems by applying two dimensional constraints over
the parameters. Using data from six countries, we compare and rank, both visually
and numerically, the models’ fitting qualities. An important section of this dissertation considers the development of forecasting models that produce non-diverging,
joint mortality rate scenarios.
It is found that the CAE model fits the data best. Another important finding
is that the Li and Lee model potentially suffers from robustness problems, when
calibrated using maximum likelihood.
Since we propose mortality models which can be readily used in the business
environment, a large chapter of the dissertation deals with number of practical,
longevity related, actuarial applications. The two best fitting models have been
used to produce the calculations. The survival index and mortality dependent annuities are among the quantities that we review in details. Additionally we propose
and derive a general framework for calculation of the complex solvency capital requirements (SCR) reserves in the case when multi-population mortality models are
used.
The main advantage of a multi-population mortality modeling - the correlations
between the individual populations, is used to derive hedging strategies related to
longevity risk. We can effectively hedge longevity risk within different populations
and this is an important and viable de-risking option in the aspect of the multi-population mortality models. We conclude that the CAE model is easily applicable
for variety of multiple population problems found in the actuarial practice today. In
comparison to other well established models, the CAE performs on equal scale and
in many cases the results are even better.James Watt Scholarshi
Gendered career decision-making : occupational segregation in Modern Apprenticeships
Get PDFThis study seeks to learn from those who make gender atypical career decisions.
Individuals making explicitly gendered career decisions which conform to stereotypical
expectations and gender biases leads to occupational segregation within the labour
market. Theoretical and empirical literature focuses on homogeneous gender typical
groups and therefore gender-typical rather than atypical career decision-makers. In
contrast, in this study, gendered career decision-making is explored through new research
which builds on the work of Bimrose (2001; Bimrose et al 2014) on gender and career
and Campbell (Thomson, Campbell and McKay, 2005; Campbell, McKay and Thomson,
2006; Campbell et al. 2009; Campbell and Gillespie, 2017) on Occupational Segregation
in Modern Apprenticeships. This project uses participants on the Scottish Modern
Apprenticeship Programme as a data source. Following a pragmatist mixed methods
orientation, a quantitative survey (N = 459) and five qualitative interviews are undertaken
with Modern Apprentices in Scotland. The outcomes of the research include novel
findings pertaining to apprenticeship provision and the demographics of Modern
Apprentices. The analysis also pinpoints specific directions for future research in the
career guidance and development discipline. In limiting the qualitative data collection to
a specific cohort, the research offers the first opportunity to engage in critical insight into
the nature and efficiency of work undertaken to address occupational segregation within
the career information, advice and guidance sector itself via Modern Apprenticeship
provision. Additionally, the research makes an explicit practical contribution to
knowledge in relation to careers practitioner-researcher methodologies and practice
Optimisation of chlorine dioxide generators and investigation into an ultra-pure chlorine dioxide generation method for drinking water treatment
Get PDFChlorine dioxide (ClO2) is an oxidant used across many different industry sectors for water
treatment, including for the treatment of drinking water. Chlorine dioxide has been successfully
applied to drinking water supplies for disinfection, oxidation, colour reduction and taste and
odour control.
Historically chlorine, as gaseous Cl2 or sodium hypochlorite solution, has been used as the
major disinfectant in drinking water treatment plants (DWTP). Research linking the generation
of trihalomethanes (THM) as by-products from the chlorination of water is causing a slow
withdrawal from chlorine dosing within the drinking water industry, allowing alternative
disinfectants to become more widely utilised.
Alternative chemical disinfectants are also not trouble free. Chlorine dioxide produces chlorite
(ClO2
-
) and chlorate (ClO3
-
) inorganic disinfection by-products (DBP). Chlorite and chlorate
ions are highly undesirable, potentially toxic, by-products formed during the commercial
generation of chlorine dioxide. Chlorate was relatively unspoken about within the water
industry until recently as it was found to be a degradation product present in sodium
hypochlorite solution, a chemical commonly used for chlorination. Increased awareness and
upcoming changes in regulation concerning disinfection by-products are causing increased
scrutiny to be placed on all chemical disinfection processes.
Manufacturers of chlorine dioxide generators commonly base the performance of their
equipment upon ClO2 output and conversion efficiency of sodium chlorite precursor to chlorine
dioxide. Conversion efficiencies, expressed as ClO2 percentage yield, greater than 95% are the
industry standard for commercial ClO2 generators. Conversion efficiency expressed in this way
only details the ClO2 concentration generated, it gives no additional information on the
concentration of DBPs produced. The presence of ClO2
- in the product solution is overlooked
and the formation of chlorate is assumed to be negligible and therefore there was no great
concern over chlorate transfer to the treated water. Since performance of generators are based
on these simplifications, the purity of the ClO2 product is an important parameter that is often
unknown and unspoken of.
Scotmas Ltd have taken this opportunity to investigate the scale of DBP formation, particularly
concerned with chlorate, in their ClO2 generators with subsequent optimisation of the process
to reduced DBPs produced. This entailed an investigation into the purity of solutions produced by a 3.5 ghr-1 ClO2 reactor subject to varying conditions. The effects of increasing chemical
retention time within the reactor and increasing acid concentrations were investigated. It was
found that a retention time of greater than 17 minutes was required to produce the highest purity
ClO2 solutions and that a reduction in acid dose, reduced by 60% in volume compared to
sodium chlorite dose, continued to generate ClO2 solutions of high purity.
To satisfy future regulation changes and customer demand a commercial generator able to
efficiently produce an ultra-pure ClO2 product is required. Initial research and investigations
were carried out to design an ultra-pure ClO2 generator. The design concept is to generate ClO2
inside a reactor which allows the ClO2 gas to subsequently be removed from the reactor and
absorbed in water to form an ultra-pure ClO2 solution product. Techniques, such as ultrasound
and aeration, were investigated on a small scale to evaluate their effectiveness at degassing
ClO2 from solution. The feasibility of incorporating each technique into the reactor design was
also considered. Ultrasound was found to increase the rate of ClO2 degassing from solution,
although it was concluded that the technique was not effective enough to be incorporated into
a commercial ClO2 generator. Aeration of ClO2 solutions dramatically increased the rate of
ClO2 degassing, although the effects of adding large quantities of air to a process could be
problematic in real installations. The short trial investigating aeration produced respectable
results and has been suggested as the technique to investigate further for incorporation in to an
ultra-pure ClO2 reactor
Increasing complexity in molecular chemical dynamics
Get PDFCrossed molecular beam (CMB) methods are combined with velocity map imaging (VMI) in
order to study the scattering of gaseous polyatomics from colliders of increasing complexity.
In addition to this, molecular dynamics (MD) simulations are used to model the surfaces of a
range of atmospherically relevant fatty acids and mixtures of hydrocarbons.
The first known measurements of k-j-k′ correlations for an inelastic scattering system, are
reported. The scattering system of choice was NO(A, 2+) + Ne, with the NO(A) initially
rotationally excited to the N = 4, j = 3.5 state, making this also one of only a small number of
studies of initially rotationally excited NO(A). During excitation molecules are aligned using
linearly polarised light, allowing for the extraction of both differential cross sections (DCSs)
and 0
2
polarisation dependent DCSs (PDDCSs).
Results of scattering experiments involving NH3 and a series of atomic and molecular
colliders of increasing size are reanalysed using a fitting routine modified by the author.
Where Ar and D2 are used as co-colliders, the DCSs extracted are compared to those from
quantum scattering (QS) calculations. Good experiment-theory agreement is found for the
work involving Ar. For the NH3 + D2 work, however, a much higher degree of product D2
excitation is observed in the experiments than predicted based on theory. DCSs are also
extracted from data on the scattering of NH3 from a series of hydrocarbons, representing one
of the first systems involving polyatomic-polyatomic scattering.
MD simulations of the vacuum-liquid interfaces of members of the oleic acid family, and of
mixtures of squalane and squalene, are presented, with an emphasis placed on which groups
are preferentially present at the surface, as opposed to the bulk. An above-statistical
distribution of methyl groups is observed at the interface, with the implications of this for
atmospheric pollution cycles discussed
Dialogue interpreting in Psychological Medicine : an exploration of rapport management practices
Get PDFThis thesis explores how the relational dimension of language use (Brown and Yule, 1983) is discursively co-constructed and perceived by the interlocutors that took part in a series of interpreter-mediated medical consultations. The interpreter-mediated encounters (IMEs) under scrutiny took place in an outpatient mental healthcare (MHC) clinic in Scotland called Psychological Medicine. This study is of an exploratory and qualitative nature, underpinned by a social constructivist epistemology. Also, it was empirically enabled through two datasets gathered using methods of data collection inspired by ethnographic approaches. Dataset 1 consists of transcriptions of three audio-recorded IMEs between an English-speaking consultant psychiatrist, a Spanish-speaking patient and three professional interpreters. Dataset 2 consists of retrospective interviews conducted with participants that took part in the consultations under scrutiny. The analysis was conducted in two stages. Discursive behaviours of interest were firstly traced in dataset 1 and then triangulated with the information gathered through dataset 2.
Relational dynamics are operationalised in this thesis following Spencer-Oatey’s (2008) rapport management (RM) theory, grounded in the field of interactional pragmatics. By applying the principles of RM to the analysis of the two datasets, I shed light onto participants’ RM practices and resulting relational outcomes in the analysed IMEs. To do that, I present analytical descriptions of a selection of excerpts where occurrences of rapport-sensitive speech acts (RSSAs) are reported, the reasons for their occurrence, and the ways in which they are managed by all participants. Ultimately, the findings provide insights into how interlocutors create and negotiate interpersonal meanings both triadically and dyadically; the role that contextual factors play in this process; and, finally, how all participants, including interpreters, are actively engaged in efforts to manage the interactional balance by discursively handling face sensitivities, behavioural expectations and interactional goals
The daily and intradaily effects of UK director dealings on stock trade price and non-price characteristics
Get PDFThis thesis proposes a new classification of insider dealings based on their qualitative
characteristics and their execution strategy. First, this thesis finds that the ‘stated
purpose’ characteristic reported in the announcements of insider dealings at the London
Stock Exchange helps distinguishing between discretionary and non-discretionary
dealings, and that the former, especially discretionary sales, are associated with higher
abnormal returns. Second, this thesis introduces a new algorithm for matching insider
dealing announcements to actual executed trades with a much higher detection rate
compared to past papers. The first analysis uses the detected trades to identify intraday
stealth trading and investigates how this affects subsequent pricing. The results indicate
that stealth-trading practices are associated with weaker and longer-lived information
signals. When directors face shorter-lived negative information, they opt not to trade
stealthily and execute their intended sale in one large order. In addition, their holding
status helps to explain why they are rushing to sell shares when they are in the possession
of negative information. Nowadays, UK directors tend to have large shareholding
percentages, as well as high potential ownership from future stock rewards. They,
therefore, rush to sell shares but not rush to buy shares. The second analysis uses standard
measures of adverse selection costs to investigate the level of information asymmetry on
the days of director trades. These adverse selection measures show that there are higher
levels of information asymmetry and adverse selection costs on days with director
upstairs informed trades. Some upstairs trades are subject to a pre-trade transparency
requirement while others are not. The third analysis investigates the price and non-price
impacts around director trades with a focus on how pre-trade transparency of director
trades affects the market ability in uncovering the implied private information. The
analysis shows evidence that the pre-trade transparency requirement helps the market
uncover different levels of implied information by UK director trades. The lack of pretrade transparency reduces the ability of the market to incorporate the implied private
information. This stresses out the importance of transparency regulatory requirements.Heriot-Watt University and Edinburgh Business School scholarshi
Context modelling for visually grounded response selection and generation
Get PDFWith recent progress in deep learning, there has been an increased interest in visually
grounded dialog, which requires an AI agent to hold a meaningful conversation with
humans in Natural Language about visual content in other modalities, e.g. pictures
or videos.
This thesis contributes improved context modelling techniques for multi-modal
visually grounded response selection and generation. We show that knowing about
relevant context encodings enables a system to respond more accurately and more
helpfully to the user request. We also show that different types of context encodings
are relevant for different multi-modal visually grounded tasks and datasets.
In particular, this thesis focuses on two specific scenarios: response generation
for task-based multimodal search and open-domain response selection for image-grounded conversations. For these tasks, the thesis contributes new models for
context encoding, including knowledge grounding, encoding history, and multimodal
fusion. Throughout these tasks, the thesis provides an in-depth critical analysis of
shortcomings of current models, tasks and evaluation metrics
Multiscale dual-continuum modelling of deformable porous media
Get PDFWithin the geosciences, we are often challenged by how to model the coupling
of physical phenomena across varying space and time scales, as well as between
different phenomena themselves. As a result, we forgo accuracy and physical
consistency/understanding, in favour of efficiency and practicality. To address
these tradeoffs we can use multiscale and multiphysics modelling. In this work,
we are concerned with multiscale behaviours owing to the coupling between
a microscale model and a (macroscopic) dual-continuum model. For the multiphysics component, we consider the coupling between linear deformation and
flow, referred to as poroelasticity.
Accordingly, the goal of this thesis is to apply multiscale and multiphysics
modelling concepts to the study of strongly heterogeneous (deformable) porous
media, to better understand and represent the links between various scales of
interest. We split this work into three main parts.
Part one investigates the relations between microscopic and dual-continuum
poroelastic constitutive models, including previously introduced phenomenological models. To do so, we use micromechanical approaches. Subsequently, starting from the microscale, we derive a fully anisotropic dual-continuum poroelastic
constitutive model using homogenisation. We then show how the resulting model
is related to constitutive models available in literature. For these previously introduced models, we use micromechanical considerations and analytical solutions
to compare and contrast the various modelling concepts used in their derivation. We also investigate various simplifying assumptions made by past users of
these models. On the basis of our studies we provide recommendations for how
and when to use the various dual-continuum poroelastic constitutive modelling
concepts and simplifications.
Part two introduces a numerical framework for poroelastic dual-continuum
modelling. We subsequently use this framework to further study the links between
microscale and macroscale poroelastic materials. Our numerical framework considers anisotropy and uses a hybrid discretisation suited for the flow and deformation subproblems accordingly. We benchmark the resulting framework
against analytical solutions and demonstrate its use on a complex geological
grid. With the framework in-hand we compare and study dual-continuum behaviours against microscale representations given various modelling and material
assumptions on the latter. We present a number of tests starting from isotropic cases, progressing to more complex anisotropic cases. Our results show that anisotropy can have measurable effects on coupled behaviours. However, for the
tests considered, we show the dual-continuum approach is capable of capturing
the global poroelastic behaviours of microscopic representations.
Finally, part three establishes a computational multiscale approach based on
machine learning to improve the accuracy of macroscopic approaches in subsurface modelling. Here the idea is to use data-driven modelling as a surrogate
constitutive model within a hierarchical multiscale setting. Accordingly, we detail the framework, describing the key components and considerations therein.
We then apply the framework to the problem of inter-continuum mass transfer, whilst considering an uncoupled (flow only) dual-continuum representation.
We couple the resulting data-driven model to a physics-based model leading to a
hybrid machine learning-physics-based approach. We show the resulting hybrid
method to give high quality results with respect to a microscale model, without
the computational expense of the latter
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