The numerical study of 3-dimensional laminar hypersonic blunt-fin interactions

The three-dimensional numerical simulation of a Mach 6.7 perfect gas, with a unit Reynolds number of 7.6 x 106m-1, over several configurations of a blunt-fin attached to a flat plate are carried out. The resulting interference flowfield is reported in this thesis.The laminar Navier-Stokes code developed by Narvarro-Martinez [47] has been modified to solve any general three-dimensional problem, and the complete Navier-Stokes equations. The numerical scheme is operator split, allowing independent numerical schemes to be used on each of the individual contributions to the Navier-Stokes, which can be combined later to advance the entire solution in time. The inviscid part uses a first order Godunov method with a HLLC approximate Riemann solver; second order accuracy is achieved through the MUSCL approach. The viscous contribution is modeled by a centered difference scheme. An iterative matrix solver is used to advance the implicit solution in time. To handle large three-dimensional grids, the code is implicit and run on a parallel computer cluster. The three-dimensional results from the various blunt-fins simulated show a complex rich three-dimensional structure, with several horseshoe vortices formed within the separated flow. Extremely large heat transfer rates have been measured along the path of these vortices on the plate surface, and on the leading edge of the unswept blunt-fin. In particular cases heat transfer rates as high as (h/hu)?60 were measured for the 5mm diameter fin. The 5mm fin results show remarkable similarity to the experimental results obtained by Schuricht [53]. The results obtained using a swept fin, and a fin of doubled fin diameter also show good agreement with the trends observed by Schuricht and others for a laminar interaction.<br/

Identifying Lead Compounds for S100P in Pancreatic Cancer Therapy Using in Vitro Biophysical Techniques

The protein S100P has been associated with the aggressiveness of several neoplastic disease, including pancreatic ductal adenocarcinoma (PDAC). S100 proteins are a family of calcium binding proteins that are small dimeric members of the EF-hand superfamily of Ca2+ binding proteins. In pancreatic ductal adenocarcinoma, protein S100P is overexpressed, and thereby meditate tumour growth, drug resistance and metastasis. Extracellular S100P binding to the cell surface receptor for advanced glycation end products (RAGE), triggers downstream signalling pathways and mediates cell growth and differentiation, cell cycle regulation and metabolic control. An effective treatment strategy would be to disrupt the formation of this S100P-RAGE complex by blocking the active binding site of S100P to the RAGE receptor. The aim of the present study was to investigate the interactions of drug compounds that are designed to block the S100P-RAGE complex formation. In order to perform this S100P protein was expressed in Escherichia. coli using a recombinant plasmid for wild type S100P and purified by affinity chromatography using a HisTrap column. The purity of the protein was assessed using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The concentration of the purified protein was determined by either the Bradford assay or bicinchoninic acid assay (BCA). In this study, the interactions sites of the recombinant S100P with each of the compounds was assessed by nuclear magnetic resonance (NMR) spectroscopy. The interaction sites were modelled by a HADDOCK approach, using the interacting residues as constraints to model the structure. In conclusion the ligands C72, IBS409, IBS798 and IBS863 were identified to interact with S100P mainly in the hydrophobic pockets of the protein S100P. Binding sites of the ligands were identified via NMR, and the binding was found to be dominated by hydrophobic interactions. Further ITC experimentation may be required in order to gain an understanding of the stoichiometry and the binding affinity for these ligands

A Study on Agrotourism Development in Sri Lanka

Tourism is the one of the largest industries in the world as well as in Sri Lanka and is the fourth largest earner of foreign exchange the national economy with positive and negative aspects. However agro tourism will not replace traditional tourism but will hopefully introduce a more sustainable form of tourism to the country. Agro based tourism is part of rural tourism and relates to tourism on farms. Agriculture has always been deeply related with the social, cultural and economic aspects of Sri Lankan history.   The study was conducted to estimate supply side as well as demand side feasibility. Supply side feasibility was conducted in Horana destination site. A tourists’ opinion survey was conducted to collect the prospective of tourists at the departure launch of Bandaranayake International Airport. Feasibility of the location was measured by an assessment tool, which was developed by Sustainable Tourism Pty Ltd in Queensland, Australia. Since it is positive, developed the hypothetical sustainable tourism destination with stakeholder analysis. The demand side survey was carried out through face-to-face interview.   As a conclusion Based on the potential index proposed destination falls to the “High potential zone category” but marginally. Stakeholders analysis implies that lot of marketing promotions have to be done, in local as well as international level, for agro tourism development in Sri Lanka. There were significant correlations between willing to pay for the facility with age, nationality, agro tourism familiarity, and experience and education level. Based on the regression can be concluded, willingness to pay has positive significant relationship with education and experience on agro tourism. Sri Lanka has a great potential to the development of agro-tourism, because of natural conditions and different types of agro products as well as variety of rural traditions, festivals.   Key terms: Agro tourism, Supply side feasibility, Demand side feasibility, willingness to pay, Contingency valuatio

Information-Theoretically Private Federated Submodel Learning with Storage Constrained Databases

In federated submodel learning (FSL), a machine learning model is divided into multiple submodels based on different types of data used for training. Each user involved in the training process only downloads and updates the submodel relevant to the user's local data, which significantly reduces the communication cost compared to classical federated learning (FL). However, the index of the submodel updated by the user and the values of the updates reveal information about the user's private data. In order to guarantee information-theoretic privacy in FSL, the model is stored at multiple non-colluding databases, and the user sends queries and updates to each database in such a way that no information is revealed on the updating submodel index or the values of the updates. In this work, we consider the practical scenario where the multiple non-colluding databases are allowed to have arbitrary storage constraints. The goal of this work is to develop read-write schemes and storage mechanisms for FSL that efficiently utilize the available storage in each database to store the submodel parameters in such a way that the total communication cost is minimized while guaranteeing information-theoretic privacy of the updating submodel index and the values of the updates. As the main result, we consider both heterogeneous and homogeneous storage constrained databases, and propose private read-write and storage schemes for the two cases.Comment: arXiv admin note: text overlap with arXiv:2302.0367

ACCOUNTING AND FINANCIAL REPORTING RECOGNITION OF FIRMS’ HUMAN CAPITAL INVESTMENT: AN EMPIRICAL INVESTIGATION OF FIRMS IN THE FTSE 100 LISTING OF THE LONDON STOCK EXCHANGE

Firms’ spending on their employees is written off as expense to the annual financial statements under the current accounting treatment. This accounting treatment has been debated over decades, since employees are arguably claimed as the true value creators of firms’ intellectual capital. Value creation potential of employees, identified theoretically as human capital has been researched for valuation and measurement for accounting recognition of human capital investment and decision usefulness of financial reporting recognition through mandatory and mostly voluntary disclosure. Research evidence are found under different phenomenon namely; social capital, intellectual capital, human capital, etc. considering, investment, accounting and reporting practices, though on an ad-hoc basis, highlighting the need for a study covering a holistic picture of the accounting and financial reporting recognition of human capital investment. Hence, the research is conducted, addressing the current practice of accounting and financial reporting recognition of firms’ human capital investment, considering both determinants and consequences of the practice utilising a stakeholder approach. The research is undertaken with data collected from annual reports of firms of FTSE 100 listing of London Stock Exchange for five accounting years, (2004-2009) chosen subjected to data availability, analysed using panel data analysis techniques with fixed and random effect estimators coupled with pooled linear regression as an alternative approach. The results of the study indicated a significant variance in the practice implying positive influences on promoting the practice accounting and financial reporting recognition of human capital investment. The results further indicated the requirement of a framework governed by standards and guidelines in promoting the practice accounting and financial reporting recognition of firms’ human capital investment

Identification of Genes Expressed in the Anterior Pituitary Associated With Water Restriction in Beef Cattle

Water is an essential nutrient and is required for growth, metabolism, lactation, and reproduction. Without water, livestock production would not be possible. Despite its importance, water requirements in livestock have not received much attention from the research community since the 1950s. The most recent edition of the Nutrient Requirements of Beef Cattle (8th edition) relies on literature from the 1950s or earlier for defining water requirements in beef cattle. Since the time these requirements were estimated, much has changed with regards to body size, genetics, and productivity of our livestock herds, including beef cattle. Global surface temperatures have increased in the last 20 years leading to climate variability, drought conditions, and desertification. Range animals may be exposed to more variable water supplies. Nutrigenomics research in livestock has largely focused on interactions between dry matter components of the diet and genomics. Transcriptome and genomic variation in response to changes in water intake have not been studied to our knowledge. Given the importance of water in livestock diets, this gap in our understanding of livestock nutrigenomics is significant. RNA-seq analysis was carried out on total RNA from anterior pituitary of beef cattle followed by water restriction (control, n = 3 and water restriction, n = 3). 14,280 genes were deemed to be expressed (\u3e4 reads per gene per animal), 40 of which were shown to be statistically significantly differentially expressed (SDE) at a false discovery rate (FDR) of 0.1% with a ≥2-fold change between control and water restricted animals. GOseq/ KEGG pathway analysis showed that SDE genes with ≥2- fold change was associated (P \u3c0.05) with one KEGG pathway and six Curated Reactomes pathways associated with G protein-coupled receptor incorporated hormone secretion and transport. Most interestingly, all these pathways were related to Arginine Vasopressin (AVP) which is one of the major regulators of water balance. RNA-seq analysis suggested that, to regulate plasma osmolarity from water restriction, the major changes in anterior pituitary gene expression in water deprivation cattle were related to release of AVP into the circulation and transportation to the kidney where AVP binds to the vasopressin type 2 receptor. This indicates the crucial role of AVP in regulating plasma osmolarity in response to water restriction. This study provides valuable insights into the genomic response of beef cattle to water restriction, highlighting the significance of AVPrelated pathways in maintaining water balance. The findings contribute to advancing our understanding of water requirements in modern livestock and emphasize the need for updated guidelines in the Nutrient Requirements of Beef Cattle. Ultimately, this research can aid in the development of more efficient management strategies to ensure optimal livestock health and productivity in the face of climate variability and limited water availability

The effect of stone protrusion on the incipient motion of rock armour under the action of regular waves

Rock armour is often used to protect the seabed around offshore structures like oil platforms, wind farms, undersea cables etc. This thesis describes a laboratory study to investigate the effect of stone protrusion on threshold movement of rock armour under regular waves. Tests were carried out to investigate the incipient motion of light weight test spheres of differing density and diameter in the range, d = 9.5mm-31.8mm, resting on a rough bed of 19mm glass marbles in a wave flume. In past studies, researchers have used turbulence measurements, shear plate apparatus, hot film techniques etc., to quantify the bed shear stress. In the present study, shear stress was deduced from direct measurements of pressure on the surface of a 50mm spherical bed element. Advance flow measurement techniques such as Laser Doppler Velocimetry (LDV) and Volumetric Three-component Velocimetry (V3V) were also carried out for flow measurement and visualisation. It was found that the Shields critical shear stress increased when stone protrusion was gradually reduced following an exponential relationship. For each wave period a different Shields shear stress versus protrusion curve was obtained. When the wave period increased the curve shifted towards that for currents previously obtained by Fenton & Abbot (1977) and Chin & Chiew (1993) suggesting that for longer wave periods under the field conditions where high Reynolds/KC number flows exist, the curve obtained for currents is applicable. The method of rock armour placement crucially influences the stability of a bed protection. Significant reduction in bed damage can be achieved by placing stones to an optimum protrusion level of 0.2d above mean bed level. A model bed protection made of crushed natural rocks (anthracite) showed that the damage to a “levelled” bed is 50% less than in a randomly placed bed. This is because the fraction of the exposed stones increases when rocks are dumped from a barge or a side stone dumping vessel as opposed to reduced exposure observed in a levelled bed

Quantum Symmetric Private Information Retrieval with Secure Storage and Eavesdroppers

We consider both the classical and quantum variations of $X$-secure, $E$-eavesdropped and $T$-colluding symmetric private information retrieval (SPIR). This is the first work to study SPIR with $X$-security in classical or quantum variations. We first develop a scheme for classical $X$-secure, $E$-eavesdropped and $T$-colluding SPIR (XSETSPIR) based on a modified version of cross subspace alignment (CSA), which achieves a rate of $R= 1 - \frac{X+\max(T,E)}{N}$. The modified scheme achieves the same rate as the scheme used for $X$-secure PIR with the extra benefit of symmetric privacy. Next, we extend this scheme to its quantum counterpart based on the $N$-sum box abstraction. This is the first work to consider the presence of eavesdroppers in quantum private information retrieval (QPIR). In the quantum variation, the eavesdroppers have better access to information over the quantum channel compared to the classical channel due to the over-the-air decodability. To that end, we develop another scheme specialized to combat eavesdroppers over quantum channels. The scheme proposed for $X$-secure, $E$-eavesdropped and $T$-colluding quantum SPIR (XSETQSPIR) in this work maintains the super-dense coding gain from the shared entanglement between the databases, i.e., achieves a rate of $R_Q = \min\left\{ 1, 2\left(1-\frac{X+\max(T,E)}{N}\right)\right\}$

Performance assessment methods for the behaviour of natural and artificial harbour inlets

Thesis (M.E.Sc.) -- University of Adelaide, Dept. of Civil Engineering, 199