Though water is the most essential element of life in most developing countries clean drinking water is supplied intermittently to consumers. Municipalities are often under the impression that intermittent supply is an ideal measure to conserve water. With over a billion people grappling with deteriorating infrastructure and water scarcity, it is impossible to neglect the effects of intermittent supply. It is essential to examine the origin of the problem, quantify the effects or consequences and then provide feasible solutions. Hence, this thesis provides a comprehensive review of the existing condition of water supply systems in developing countries but more importantly, examines the causes of the intermittency and highlights the significant economic incentive that could be achieved by maintaining a continuous supply system. Finally the thesis concludes with a series of feasible solutions including short-term and long-term plans that would assist in a complete migration towards 24-hour supply.

Though water is the most essential element of life in most developing countries clean drinking water is supplied intermittently to consumers. Municipalities are often under the impression that intermittent supply is an ideal measure to conserve water. With over a billion people grappling with deteriorating infrastructure and water scarcity, it is impossible to neglect the effects of intermittent supply. It is essential to examine the origin of the problem, quantify the effects or consequences and then provide feasible solutions. Hence, this thesis provides a comprehensive review of the existing condition of water supply systems in developing countries but more importantly, examines the causes of the intermittency and highlights the significant economic incentive that could be achieved by maintaining a continuous supply system. Finally the thesis concludes with a series of feasible solutions including short-term and long-term plans that would assist in a complete migration towards 24-hour supply.

This research study consisted of three parts.  In the first part two surveys were conducted, one among General Practitioners (GPs) in Grampian Area of Scotland and the second among Consultant Vascular Surgeons throughout the United Kingdom and Ireland, which aimed to explore the attitudes towards management of secondary risk factors in patients with intermittent claudication.  Postal questionnaires were used to determine how GPs and Consultant vascular surgeons screened for and controlled the major risk factors - cigarette smoking, hypertension, diabetes and hyperlipidaemia, whether and what anti-platelet treatment was prescribed, and the availability of facilities such as smoking cessation clinics and supervised exercise programmes for patients with intermittent claudication.  The findings from the GP survey were compared with the responses to a questionnaire of patients with intermittent claudication referred to the Vascular Clinic, Aberdeen Royal Infirmary and to the results of blood investigations. The results of the two surveys showed that a significant proportion of both GPs and Consultant Vascular Surgeons do not abide by current recommendations on management of major secondary risk factors.  This may be partly due to the lack of national guidelines and the paucity of local guidelines specifically on the management of secondary risk factors in intermittent claudication.  The surveys have also identified serious deficiencies in the availability of supervised exercise and smoking cessation programmes for this group of patients.  Only a very small minority of consultant vascular surgeons have access to a vascular physician.  Furthermore a wide discrepancy was noted between the claims made by GPs.

Thesis (M Nursing (Advanced Practice))--University of South Australia, 1995

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.

Orientador: Ricardo Augusto Mazza / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-17T08:41:20Z (GMT). No. of bitstreams: 1 BarbosaFilho_FranciscoElpidioVianna_M.pdf: 5790999 bytes, checksum: fa54092632bda478168f180355312ced (MD5) Previous issue date: 2010 / Resumo: O escoamento bifásico padrão golfada de líquido é caracterizado pela passagem alternada de pistões de líquido seguidos por bolhas alongadas de gás. Este trabalho desenvolve um estudo experimental e numérico sobre este padrão de escoamento em uma tubulação contendo uma curva de 90 graus. Essa configuração permite a passagem do escoamento vertical ascendente para horizontal em uma curva com raio interno de 410 mm e diâmetro interno da tubulação de 26 mm. O arranjo experimental permite fazer a medição das propriedades do escoamento padrão golfada antes e depois da passagem pela curva. As grandezas medidas são: a velocidade de propagação das bolhas, os comprimentos de bolhas e pistões, a frequência de passagem e a queda de pressão ao longo da tubulação. Um modelo numérico do tipo slug-tracking é empregado para capturar as alterações das características dos pistões e das bolhas durante a transição vertical para horizontal. O modelo se concentra em capturar os efeitos da mudança de direção relacionados com: a força da gravidade, a aeração pistão líquido e a espessura do filme líquido que envolve as bolhas de gás alongada. Os resultados numéricos foram favoravelmente comparados em relação aos dados experimentais / Abstract: The slug flow pattern is characterized by the alternating passage of liquid slugs trailed by elongated gas bubbles. This work develops an experimental and numerical study in slug flow regime occurring in a 90 degree pipe bend. The pipe bend allows the transition from upward vertical flow to horizontal flow in a curve with inner radius of 410 mm and inside diameter of 26 mm. The experimental set up allows the measurement of the slug flow properties at the inlet and outlet of the pipe bend. The quantities measured are: bubble's nose velocity, bubble and slug lengths, the frequency of passage and the pressure drop. A numerical slug tracking model is employed to capture the changes of the slugs features during the vertical to horizontal transition. The modeling efforts concentrate on the effects of the change of direction on: the gravity force, liquid slug aeration and on liquid film thickness surrounding the elongated gas bubbles. The numerical results compare favorably against the experimental data / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica

Smart things, spaces, and structures are created by embedding computation into them. Embedded computers sense, compute, and communicate at the edge, closer to the physical rather than the cyber world. Not any computer can be embedded, because many deployment settings demand small size, long lifetime, and robustness to a harsh environment. .

Faculty of Science School of Physiology 9808215t romainh@physiology.wits.ac.za / There is a high prevalence of insulin and leptin resistance and increased cortisol concentrations in sleep apnoea patients, independent of obesity. Chronic intermittent hypoxia is used an experimental animal model to simulate the hypoxia occurring in sleep apnoea patients. The aim of this study was to measure plasma insulin and leptin concentrations and hypothalamic-pituitary-axis activity in rats exposed to either intermittent hypoxia (CIH) or sham hypoxia (SH) for fourteen days. To induce CIH plexiglass cylinders were flushed with 100% nitrogen for nine seconds every 90 seconds, seven hours/day. The rats were weighed each day during the exposure period. Venous blood samples for insulin and leptin were collected on days one, three, five, eight and fifteen. Faecal samples were collected to measure glucocorticoid metabolites. There was no significant difference in the daily change in body weight between the rats exposed to CIH compared to the rats exposed to SH (unpaired t-test). Plasma insulin concentrations were not affected by CIH. In both groups of rats plasma leptin concentrations were significantly higher on day fifteen compared to day five (p=0.03, unpaired t-test). Glucocorticoid metabolites were significantly increased in the intermittent hypoxia group on day two (p=0.003 one-way ANOVA). In conclusion, exposing normal weight rats to CIH for fourteen days resulted in a transient iv increase in HPA axis activity on day two and an elevation in plasma leptin levels, in both groups of rats, at day fifteen.

No description available.

This thesis explores the security of intermittent devices, embedded systems designed to retain their state across periods of power loss, for cases both when the device has an excess of available energy and when power loss is unavoidable. Existing work with intermittent systems has focused on the problems inherent to the intermittent paradigm and ignored the security implications of persistent state across periods of power loss. The security of these devices is closely linked to their unique operational characteristics and are addressed here in two studies. First, the presence of an energy harvester creates an opportunity to use excess energy, available when additional energy is harvested after the local energy reservoir is filled, to precompute security related operations. Precomputation powered by this excess energy can reduce the cost of expensive tasks during periods of energy scarcity, potentially enabling the use of expensive security operations on traditionally unsecured devices. Second, when energy is limited and intermittent operation is required, the secure storage of checkpoints is a necessity to protect against adversary manipulation of the system state. To examine the secure storage of checkpoints a protocol is implemented to ensure the integrity and authenticity of a device's checkpoints, and evaluated for its energy overhead and performance. The cost of properly ensuring the integrity and authenticity of these checkpoints is examined to identify the overhead necessary to execute intermittent operations in a secure manner. Taken together, these studies lay the groundwork for a comprehensive view of the current state of intermittent device security. / Master of Science / This thesis explores two unique aspects of the intermittent computing paradigm, the precomputation during periods of excess energy and the security of system checkpoints. Intermittent systems are a class of embedded device that lack a classic, consistent, energy source and instead rely on transient energy collected from their surroundings. This removes the need for connection to a power grid or battery management, but introduces challenges in operation since the device can lose power at any time. Additionally, excess energy is available to these systems when they have filled their local energy reservoir, a capacitor or small rechargeable battery, and additional energy can still be collected form the environment. In this case, it is possible to begin precomputing energy intensive operations to enable more operations at a later time on a limited energy budget. Since their power source is inconsistent, intermittent systems checkpoint their current state to allow execution to resume at the beginning of the next power cycle. The security ramifications of saving the current system state into a checkpoint have not been considered in the state of the art. This thesis implements a protocol to properly secure system checkpoints and evaluates its performance to identify the energy overhead required for a secure checkpointing scheme. The results demonstrate the need for the development of more efficient solutions within the domain. Together, the two approaches presented in this thesis provide case studies on the behavior of intermittent devices when provided with either an excess or a dearth of energy. The optimization and improvement of modern intermittent devices will need to address both of these extremes as the field is further improved.