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Understanding the influence of port community relationships on port community performance – a social capital perspective
Get PDFThis research investigates the influence of port community relationships on port
community performance through the lens of social capital. While port performance
research has traditionally focused on the micro or macro level, this study explores port
performance at the meso level and suggests the terminology of port community
performance in acknowledgement of the contributions and relevance the interactions of
port community members have on the focal port’s performance. Since this type of
investigation is a novel approach within the field of port performance research, this study
addresses this gap by employing social capital theory to the context of Scottish trust ports.
In detail, this study adopts Nahapiet and Ghoshal’s (1998) conceptualisation of social
capital and further incorporates more recent findings of Hartmann and Herb (2015) of
social capital’s influence on performance in triadic relationship settings as the latter
allows for the suitable conceptualisation of the triadic port community setting between
port authority, cargo owners and port service providers. As their performance is
influenced by the quality of their relationships and subsequent interactions, the context of
Scottish trust ports lends itself to extend social capital theory to develop an understanding
of the formers’ influence on the performance of a port.
This project employed a multiple-case study design. Two Scottish trust ports were
purposively selected in line with a set of established criteria which are shared across the
sample of suitable ports for analysis which allows for the synthesis of cases. As part of
the data collection, a total of 30 semi-structured interviews were conducted with 30
representatives of the three port stakeholder groups of port authority, cargo owners and
port service providers. The data gathered by the means of interviews is further enriched
by participant observations, informal off the record exchanges and field notes. This
project is underpinned by an interpretivist perspective. This study contributes to practice
by identifying how facets of social capital such as trust, shared values, or norms in port
community relationships positively influence port community performance which is of
particular value for smaller sized ports with diverse cargo portfolios. The theoretical
contribution of this study is twofold as it highlights how the extended setting of focal
relationships in the port community can influence the manifestation of the dark side of
social capital. Furthermore, it adds to the body of social capital theory by delineating how
existing levels of social capital aligned with one of its dimensions can facilitate the
accumulation of facets attributed to the other dimensions
Multiport beamforming system based on reconfigurable waveguide phased antenna array for satellite communication applications
Get PDFA multiport K/Ka-band beamforming system based on the reconfigurable
waveguide phased antenna array is presented in this thesis. The waveguide structure is
used to achieve low loss, wideband performance, and simple installation and
maintenance. The antenna array is adopted to compensate for the high propagation loss
in higher frequency, which also provided flexible functions for multi-user wireless
communication applications.
The reconfigurable waveguide transitions are the most crucial component in this
beamforming system to achieve dual linear-polarized/left-handed circular-polarized/right-handed circular-polarized functions at K/Ka-band respectively by using
the reconfigurable structure. It provided much better performance in bandwidth
compared with the recent dual-band/dual-mode waveguide transitions.
The waveguide antenna and antenna arrays are reconfigurable and replaceable
to meet the design purposes and requirements for linear-polarized/left-handed circular-polarized/right-handed circular-polarized functions. The ultra-bandwidth from K-band
to Ka-band provided advantages in saving cost and flexible functions due to the
waveguide antenna array parts being applicable for both transmitting/receiving systems
for K/Ka-band.
This advanced beamforming system could provide many merits such as low loss,
wideband, compact structure, high functional flexibility, lower cost, simpler
installation, and easier maintenance by using the waveguide reconfigurable. These
advantages are indicated by the sufficiently good performance in both the simulated and
measured results in this thesis, which demonstrated that this beamforming system
design is applicable for wireless communication applications in high frequency,
especially for satellite communication applications with separated unlink and downlink
systems.
The potential and prospect for a MIMO beamforming system with a multilayer
PCB feeding network are also demonstrated from the wideband performance of
multilayer SICL power divider and SICL-to-waveguide transitions in this thesis to get
a more flexible structure for a MIMO beamforming system and more compact structure
Optical diagnostics for structural health monitoring of inaccessible systems
Get PDFThe work in this thesis is concerned with the development of optical sensors for the
structural health monitoring of systems with inaccessible components in the presence of
ionising radiation. Two primary approaches to determine structural health are
investigated, these being the implementation of distance measurement sensors (to assess,
for example, the occurrence of creep/cracking) and gas sensors (to assess the occurrence
of outgassing which can be indicative of chemical ageing).
Distance measurement sensors are developed using fibre optic Fabry-Pérot interferometry
(FPI) measured in reflection. A fast-Fourier transform (FFT) of the reflected interference
spectrum is incorporated to demodulate the signal and extract cavity length information.
To mitigate noise and enhance measurement accuracy and sensitivity, spectrum
reconstruction in the form of a function-fitting algorithm (FFA) is developed, the input
of which is fed by the FFT output. The FFA demonstrates measurement improvements
of approximately one-and-a-half orders of magnitude.
To situate the fibre FPI sensors within spatially confined, closely positioned components,
turning mirrors are fabricated on two cores of multi-core fibre (MCF) which redirect the
fibre-guided light perpendicular to the fibre axis in opposite directions. This allows for
the absolute distance between component parts to be determined as Fabry-Pérot cavities
are formed on both sides of the MCF. Three different turning-mirror fabrication
processes are developed, the results from each are compared and discussed.
The distance measurement capabilities are expanded to that of a two-point measurement
system to allow for tilt measurement competencies. This facilitates further
comprehensiveness with regards to structural health monitoring. Further, two optical gas
sensors are investigated, both based on the principle of absorption spectroscopy. One
consists of evanescent wave generation in a tapered fibre and the other of incoherent
broadband cavity-enhancement. Modelled and experimental results are presented and
limitations are discussed
Planktic foraminiferal I/Ca ratios as a proxy for past seawater oxygen concentrations
Get PDFMarine carbonate I/Ca ratios are an increasingly used proxy for palaeo-oxygen
concentrations. Planktic foraminifera I/Ca ratios can give valuable information about
past oxygen concentrations in the upper water column and intermediate water ventilation,
influencing global geochemical cycles over glacial/interglacial time scales. Three aspects
of the I/Ca proxy in planktic foraminifera from the Indian and Pacific Oceans were
studied here. The first part addresses questions about the methodology of the analysis.
For mass spectrometer analysis, it confirms three different bases as potential stabilisers
to prevent iodine loss after acidic sample dissolution. Furthermore, the importance of
sufficient cleaning with hydrogen peroxide before analysis is highlighted. In the second
part, Indian and Pacific core top samples were used to test the relation of recent water
oxygen concentrations with I/Ca of various planktic foraminifera species after selecting
the core tops of interglacial age by δ18O stratigraphy and radiocarbon dating. The I/Ca
follows thermocline water oxygen concentrations even when the foraminifera live higher
up in the mixed layer. Finally, three sediment cores are used from the California Margin
and one from the Ontong Java Plateau in the West Pacific to study glacial/interglacial
changes in I/Ca of planktic foraminifera. Little change and consistently low values of
I/Ca are found along the California margin indicating low oxygen concentrations, which
contrasts with previous studies that show significant changes in oxygen concentration at
different water depths simultaneous to northern hemisphere climate events like the
Bølling/Allerød warm periods the Younger Dryas and the early Holocene. The West
Pacific core showed one large swing to higher I/Ca ratios during the last deglacial
transition indicating better oxygenation in the upper water column during the Holocene.
This is the opposite of what previous reviews have shown for other parts of the Pacific
The impact of reservoir parameters on the performance of carbonated (CO2-enriched) water injection
No full textAbstract unavailable, Please refer to PDF. Restricted access until 01.10.2024
Pushing single photon array cameras to the limits : single molecule widefield lifetime imaging
Get PDFMicroscopy has been an underpinning technology of the scientific community since it’s
conception at the end of the 16th century. Significant inventions, which are still in use
today, in the form of the fluorescence microscope and the development of fluorescent
dyes, have confirmed and enhanced microscopy’s place as a staple in science today.
However, these advancements would be dramatically reduced if the detector technology
had not progressed in parallel. With the development of Single Photon Avalanche Diodes
(SPAD) array detectors it is now possible to perform time resolved microscopy on-chip,
without the need for any additional counting electronics. This allows for the possibility
to perform widefield fluorescent lifetime imaging microscopy (FLIM) due to their fast
frame rates and single photon sensitivity.
The research presented here is based on the SPAD array technology, SPCImager. The
aim is to push the SPCImager platform to its limits by performing widefield single
molecule fluorescent lifetime imaging microscopy. The SPCImager is able to perform
this due to a dual time-gated imaging modality that allows crude time tagging capabilities
over the full array of 320 by 240 pixels.
To provide SPCImager with the most optimal and stable conditions, an objective-based
Total Internal Reflection Fluorescence (TIRF) microscope set up was designed and
developed to allow operation in either CW or Pulsed laser modalities with data being
captured on SPCImager and a commercial sCMOS/emCCD simultaneously.
To gain a more complete understanding on the deployment of SPCImager’s dual time
gates, a complete computational model was developed to simulate SPCImager’s response
to a fluorescent event. By conducting a study into optimising imaging parameters, for a
range of simulated events from 1µm carboxylate microspheres to quantum dots and single
molecules, it was possible to determine optimal settings required to return accurate and
reliable lifetimes.
SPCImager was able to perform Widefield FLIM on a range of microspheres before
demonstrating its potential and, identifying limitations, when applying this to single
molecule widefield FLIM
Imaging solutions for 4D quantitative interpretation
Get PDFDuring the production of a geomechanically active reservoir, massive pressure
depletion happens giving rise to geomechanical changes which can lead to significant
time-lapse signals across the reservoir and its surrounding. Therefore, geomechanical
characterisation of the reservoir and monitoring are very important for this type of
reservoir. In this thesis, I use pre-stack time-lapse time-shifts observed between 4D
seismic surveys for the geomechanical characterisation of the Ekofisk field which is a
geomechanically active field in the North Sea.
This thesis consists of three parts. Before using pre-stack time-shifts, post-stack time shifts can be a valuable guide toward the geomechanical activities of the reservoir. In
the first part, I estimate the post-stack time-shifts using various methods. Then, I
evaluate the advantages and disadvantages of each method in terms of their
performance in revealing the local time-lapse signals such as time-strains. I have found
that all the time-shift methods can successfully measure time-shifts. Among them, NLI
is the most outstanding method as it gives smooth time-shifts with relatively good
accuracy and the time-strains derived from there are more stable and interpretable.
In the second part, I use the reflectivity and velocity models of the Ekofisk field and
perform a finite-difference simulation to generate synthetic seismic data, followed by
imaging the generated data. Migrating baseline and monitor datasets with baseline
velocity model caused considerable mispositioning in the overburden resulting in false
amplitude-differences in the overburden. The analysis of the images shows that it is
not simply a matter of mispositioning that contaminates the seismic images. A more
serious problem caused by migration with an erroneous velocity model is the
defocusing of amplitudes. This problem cannot be solved by warping and requires a
more sophisticated remedy to correct the monitor’s migration velocity model.
In the third part, which is the major development of this thesis I measure the pre-stack
time-shifts and design a tomographic approach to utilise them for estimating the time lapse changes. First, I show how to measure the pre-stack time-shifts and discuss the
practical aspects of the process. Second, I design a ray-based tomography customised
for 4D application in order to utilise the pre-stack time-shifts and invert for velocity
changes that cause the time-shifts. Finally, I extend the tomography method into an
anisotropic inversion where both the time-lapse velocity changes and the ratio of
lateral-to-vertical strains are inverted in a two-step inversion process. The two
products of the inversion can be used extensively in the geomechanical model
calibration of the reservoirs.
Overall, my PhD research has successfully measured the time-lapse velocity changes
and the ratio of lateral-to-vertical strains. The anisotropic time-lapse tomography is a
new paradigm in the pre-stack time-lapse seismic analysis and will be an integrated
part of the geomechanical characterisation of the reservoirs
A pseudodifferential approach to the fractional Laplacian and magnitude
Get PDFIn this thesis we consider two problems related to the fractional Laplacian. One of
these is the study of the singular behaviour of solutions of boundary value problems
for the fractional Laplacian in smooth and polygonal domains. We study these
problems in model geometries using a harmonic extension of the solution to the
upper half-space. We then discuss how these problems fit in the theory of edge
pseudodifferential calculus and outline the additional steps necessary to address the
general case.
On the other hand, we study magnitude, a metric invariant of compact metric
spaces, for Euclidean domains or compact manifolds with boundary. We provide a
framework for its analysis, relating it to a boundary problem for a non-local integral
operator, which upon localisation near the diagonal is a negative order parameter-elliptic pseudodifferential operator coinciding with a negative order fractional Laplacian up to lower order terms. The inverse of this operator, when acting between
suitable Sobolev spaces, is asymptotically computed using Wiener-Hopf factorizations and methods from semiclassical analysis. As a main result, we obtain an
asymptotic variant of the convex magnitude conjecture by Leinster and Willerton
by explicit computation
Schatten-class perturbation theory of one-parameter semigroups
Get PDFThe main aim of this thesis is to further investigate the perturbation theory of
one-parameter semigroups on Hilbert spaces, whose generators are not necessarily self-adjoint. We start by exploring some of the heretofore known frameworks
relevant to this study. Most importantly, we present the efforts of E. Hille and R.
S. Phillips, which we specialize by introducing a new class of semigroup perturbations with q-Schatten class properties. Taking the Dyson–Phillips series as our
primary tool, we prove that these perturbations give rise to one-parameter semigroups with common properties that depend on q. With the help of some technical results, we show that this class allows us to define an equivalence relation
on the set of generators of immediately norm continuous one-parameter semigroups. We also study the effect of these perturbations on the resolvent of the
resulting one-parameter semigroup. Finally, we consider the concrete example
of certain Schrodinger operators and characterise some of their perturbations.James Watt Scholarshi
Influence of BREEAM, BIM, and Soft Landings on lifecycle performance of two non-domestic buildings
Get PDFThe buildings industry is the largest energy and resource consuming, and waste
and global greenhouse gas (GHG) generating sector of the industry and has long been
criticised as slow-moving, unsystematic, and inefficient. The inflated ecological footprint
of the building sector has made its sustainable development an elusive challenge. To
promptly commission a substantial change in building design and delivery performance,
there is a significant drive worldwide for digitalisation, green buildings, and integrated
stakeholder management.
This PhD research investigated the capability of three such tools, namely
BREEAM, BIM, and Soft Landings, to improve the building, as well as the associated
design and delivery processes. Two case-study projects, which were designed and built
on Heriot-Watt University campus using these tools, were closely examined throughout
their design, construction, and two-years of occupancy using an investigative multimethod approach. Soft Landings is a framework that aims to enhance briefing, handover,
and in-use performance through systematic participation of all stakeholders.
The extent to which the tools were used during the projects, and the experience of
project stakeholders, were investigated over semi-structured interviews. The financial,
temporal, and staff resources; binding drivers such as tangible project brief and regulatory
requirement; as well as early appointments and engagement of the stakeholders,
particularly the end-user client were discovered to be the most influential factors in
effective adoption of the tools. The interviews assisted with understanding the extent of
influence of the tools and the challenges in their full and effective adoption. Furthermore,
to assess the success in delivery of satisfactory, fit-for-purpose buildings, building users
were surveyed using the Building Use Studies (BUS) method. The survey results were
supplemented with seasonal commissioning, Soft Landings, and other relevant project
documents, which confirmed the importance of planned handover, detailed
commissioning, and rigorous aftercare.
Finally, the life cycle environmental footprints of the buildings were quantified
following two LCA approaches, as per the CEN/TC 350 standards and PEF method. The
significant share of the end-of-life (EoL) stage signified the importance of mandatory
reporting of these impacts for more accurate LCA assessment and more widespread
adoption of circular economy concepts in the building industry. Nevertheless, design for
circularity or waste recovery at building EoL is not adequately covered by BREEAM,
BIM, or Soft Landings. The results reconfirmed the large influence of operational energy
use upon many environmental impacts over the building lifetime, even in a BREEAM Excellent building. Climate Change and Resource use, energy carriers / fossils were the
most relevant environmental impact by contributing to half of the total normalised and
weighted emissions.
Overall, the scope of BREEAM, BIM and Soft Landings were not found
comprehensive and empowering enough to improve all the life cycle stages, reducing life
cycle impacts and operational energy use, and deliver a fit-for-purpose building. Yet, each
tool offered several benefits in these two case-studies. BREEAM, BIM and Soft Landings
enriched the design development by way of advanced consultation with final-users and
enhanced coordination between the design team, client, and project contractors. The first
case-study, the Oriam sports complex, was a successful example of Soft Landings
implementation that offered a great level of transparency, improved handover and finetuning experience to the facility management, and return on investment through
continuous reduction of operational energy. The users of the case-study that implemented
Soft Landings reported high satisfaction with the space. Ultimately, no direct correlation
was identified between BREEAM, BIM, or Soft Landings and reduced life cycle
environmental impact of the buildings
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