30 research outputs found

    Maximum risk reduction with a fixed budget in the railway industry

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    Decision-makers in safety-critical industries such as the railways are frequently faced with the complexity of selecting technological, procedural and operational solutions to minimise staff, passengers and third parties’ safety risks. In reality, the options for maximising risk reduction are limited by time and budget constraints as well as performance objectives. Maximising risk reduction is particularly necessary in the times of economic recession where critical services such as those on the UK rail network are not immune to budget cuts. This dilemma is further complicated by statutory frameworks stipulating ‘suitable and sufficient’ risk assessments and constraints such as ‘as low as reasonably practicable’. These significantly influence risk reduction option selection and influence their effective implementation. This thesis provides extensive research in this area and highlights the limitations of widely applied practices. These practices have limited significance on fundamental engineering principles and become impracticable when a constraint such as a fixed budget is applied – this is the current reality of UK rail network operations and risk management. This thesis identifies three main areas of weaknesses to achieving the desired objectives with current risk reduction methods as: Inaccurate, and unclear problem definition; Option evaluation and selection removed from implementation subsequently resulting in misrepresentation of risks and costs; Use of concepts and methods that are not based on fundamental engineering principles, not verifiable and with resultant sub-optimal solutions. Although not solely intended for a single industrial sector, this thesis focuses on guiding the railway risk decision-maker by providing clear categorisation of measures used on railways for risk reduction. This thesis establishes a novel understanding of risk reduction measures’ application limitations and respective strengths. This is achieved by applying ‘key generic engineering principles’ to measures employed for risk reduction. A comprehensive study of their preventive and protective capability in different configurations is presented. Subsequently, the fundamental understanding of risk reduction measures and their railway applications, the ‘cost-of-failure’ (CoF), ‘risk reduction readiness’ (RRR), ‘design-operationalprocedural-technical’ (DOPT) concepts are developed for rational and cost-effective risk reduction. These concepts are shown to be particularly relevant to cases where blind applications of economic and mathematical theories are misleading and detrimental to engineering risk management. The case for successfully implementing this framework for maximum risk reduction within a fixed budget is further strengthened by applying, for the first time in railway risk reduction applications, the dynamic programming technique based on practical railway examples

    Perception of Climate Change and Its Effects on Rural Livelihood in Katsina State, Nigeria

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    This study investigated the perception of climate change and its effects on livelihood in Katsina state. This study adopted cross sectional research design. Data for this study were generated from the administration of questionnaire in the study area. Data analysis was achieved using the Kruskal Wallis test. Findings of the study include; the locals identified that there are changes in the characteristics of climate elements in the area indicating climate change. The locals also identified that as a result of climate change, they have witnessed increase in the loss of agricultural land and soil quality due to erosion and reduced soil fertility (70%), reduced livestock productivity (55.6%), increase in pest and disease incidence in livestock (70%), increase in the cost of crop production (60.7%), and increase in the rate of farmer poverty (39.3%). The perception of the concept of climate change across the study area was significantly different at P<0.05 (χ2(2) =, 21303.673) implying that, the consequences of climate change in the area also vary. The study strongly advocates, the application of climate smart agriculture, reforestation and massive public awareness about the causes and effects of climate change in the study area. Keywords: climate-change, livelihood, semi-arid, greenhouse-gases DOI: 10.7176/JNSR/10-2-04 Publication date: January 31st 202

    FINANCIAL DEVELOPMENT AND ECONOMIC GROWTH: A COMPARATIVE ANALYSIS OF NIGERIA AND SOUTH AFRICA

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    Advances in the financial system have been acclaimed to improve economic growth, drawing from theories of the latter. This study set out to test this hypothesis with respect to financial institutions and markets in the two largest economies of Sub-Saharan Africa. Economic growth for both countries is measured by gross domestic product annual growth, as the explained variable. Financial development is measured by institutions and markets. The dependent variable by financial institutions includes money supply, bank branches, interest rate spread, and bank capital to asset ratio. For financial markets, market capitalization, traded value excluding top 10 traded companies to total traded value, market turnover, and stock price volatility. Data is obtained from the World Bank for both countries. Two models are developed, one for each country. For analysis, the Augmented Dickey-Fuller unit root test, and autoregressive distributive lag are employed. The results indicated that of all variables considered only money supply (financial depth by the institution) had a significant, yet negative influence on economic growth in Nigeria. No dimension of financial development is related to output in the long term for South Africa. The study inferred that financial development in both countries is yet to advance sufficiently to make desired effect on economic growth. Expansion of financial institution market and institutions in the form of exchange growth scheme (for small and medium businesses) and rural bank branching was recommended by the study

    Hydrological Modeling of Aquifers and Their Ground Water Potentials: Implications for Water Resources Planning and Management in Parts of Obio/Akpor L.G.A, Rivers State

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    Abstract This study examined the hydrological modeling of aquifers and their ground water potentials for the purposes of water resources planning and management. This was done using the electrical resistivity method employing the schlumberger electrode configuration at randomly selected stations to obtain the thicknesses and resistivities of each layer and depth to the presumably conglomeratic sand stone and its resistivity. V. E. Weli et al. 37

    Infeksjoner med parasitten Nucleospora cyclopteri (Microsporidia) i rognkjeks, Cyclopterus lumpus

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    Source at https://www.vetinst.no/rapporter-og-publikasjoner/rapporter/2019/infeksjoner-med-parasitten-nucleospora-cyclopteri-microsporidia-i-rognkjeks-cyclopterus-lumpus.Nucleospora cyclopteri (Microsporidia) is one of many parasites infecting lumpfish, Cyclopterus lumpus, and has been shown to cause disease and mortality in lumpfish. Infections in fish are often multifactorial and the impact of one agent on the development of disease can be difficult to elucidate. In addition to mortality, infections in lumpfish can lead to diseases with subsequently lowered appetite. This is of particular importance since lumpfish are used as a biological control agent, eating salmon lice, Lepeophtherius salmonis, off the salmon. Knowledge on the different disease agents of lumpfish is therefore of utmost importance. The main aim of this project was to identify how to obtain an infection-free lumpfish in land-based hatcheries and to study the impact that N. cyclopteri has on the health of the lumpfish and thereby its effect as a biological control agent. The project therefore aimed to map the presence of N. cyclopteri and other disease agents in wild caught lumpfish and in eggs/sperm, in fry and in farmed lumpfish stocked in the sea. In addition, we wanted to study the transmission pathways and clinical significance of the parasite. Unfortunately, we were not able to obtain a group of lumpfish fry infected with N. cyclopteri that we intended to follow through the land phase. The study of pathogenesis, infection dynamics, or whether an infection with N. cyclopteri pre-disposes for secondary infections, was therefore abandoned. We studied the presence of co-infections, methods for optimal sampling and tissue tropism in wild caught lumpfish in this project. Nucleospora cyclopteri was present in 60% of the sampled individuals from the waters around Averøy, in county Møre og Romsdal. The fish were analysed with regard to a range of infectious agents (viruses, bacteria and parasites) commonly found in other fish species, or previously recorded in lumpfish. No viral agents or other important pathogens were detected, but supposedly nonpathogenic microparasites, like Kudoa islandica (Myxozoa) in the muscle tissue and coccidians in the intestine, were frequently found. Nucleospora cyclopteri was detected in all tissues examined: anterior, mid and posterior kidney, spleen, heart, gills, brain, muscle liver and blood, thus indicating that the infection is systemic. The density of N. cyclopteri was highest in the anterior kidney, followed by mid and posterior kidney, spleen and gills, while the prevalence was highest in the ventricle of the heart. Observations from this study indicate that the parasite is released through urine and bile. We also show that N. cyclopteri can be detected using swabs from the skin, gill and vent, and by blood samples and gill biopsies, thus demonstrating the possibility of non-lethal detection of N. cyclopteri in lumpfish. Amongst these, the most promising non-lethal samples for detection were gill biopsies and leukocyte fractions from blood samples. Images normal histology and pathological agents from this project is included in an openly available online image database. This image database can be accessed by diagnosticians and researchers and used when evaluating pathological findings in lumpfish. While vertical transmission cannot be excluded, the results from this project indicate that this is not the dominant route. It is in any case advisable to routinely screen broodfish for N. cyclopteri to avoid using positive individuals for the production of eggs and fry. Given that N. cyclopteri undoubtedly destroys leukocytes in high numbers and over large areas of tissue, it is reasonable to assume that the parasite has an effect on the immune competence of the fish

    Notes for genera: basal clades of Fungi (including Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota)

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    Compared to the higher fungi (Dikarya), taxonomic and evolutionary studies on the basal clades of fungi are fewer in number. Thus, the generic boundaries and higher ranks in the basal clades of fungi are poorly known. Recent DNA based taxonomic studies have provided reliable and accurate information. It is therefore necessary to compile all available information since basal clades genera lack updated checklists or outlines. Recently, Tedersoo et al. (MycoKeys 13:1--20, 2016) accepted Aphelidiomycota and Rozellomycota in Fungal clade. Thus, we regard both these phyla as members in Kingdom Fungi. We accept 16 phyla in basal clades viz. Aphelidiomycota, Basidiobolomycota, Blastocladiomycota, Calcarisporiellomycota, Caulochytriomycota, Chytridiomycota, Entomophthoromycota, Glomeromycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota, Mucoromycota, Neocallimastigomycota, Olpidiomycota, Rozellomycota and Zoopagomycota. Thus, 611 genera in 153 families, 43 orders and 18 classes are provided with details of classification, synonyms, life modes, distribution, recent literature and genomic data. Moreover, Catenariaceae Couch is proposed to be conserved, Cladochytriales Mozl.-Standr. is emended and the family Nephridiophagaceae is introduced
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