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In this dissertation, an electrical discharge coating uses an isolated sleeve to form a closed space between the end surface of electrode and the work to deposit a thin film onto a substrate. The discharge occurs at the location where the two surfaces are closest and the dielectric fluid ionizes at this location to create a path for the discharge. Hence, this closed space is heated to extremely high temperature, so that a small portion of the work surface is suddenly melted with the particles in the dielectric fluid and then coated to increase its coating speed and quality. The electrode material is made of brass, the work material SKD11, and the dielectric fluid is kerosene with the WC powder concentration of 50g/L. The pulse-on and pulse-off times are 25 and 500£gs, respectively. The effects of supply voltage, electrical discharge coating time, electrical discharge gap, and powder added cycle on the coating characteristics are investigated. According to the experimental results, the electrical discharge with isolated sleeve can achieve a complete coating layer onto the surface of work. The coating thickness increases with increasing electrical discharge coating time and gap as the supply voltage is larger than the threshold voltage of electrical discharge. At the supply voltage below 250V and the added powder cycle less than 10, the coating thickness increases with increasing supply voltage and cycle. The quality of coating layer is better at the low gap distance and the high supply voltage. The hardness of coating layer is about HV 1687 which is approximately 5 times of substrate hardness using micro-hardness test. The electrical discharge without isolated sleeve cannot achieve the above-mentioned advantages.

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Shorter hospital stays increases the need for well functioning post hospital aftercare. Persons close to the patient are often involved in the aftercare and need information about self-care. This need is frequently not satisfied. The aim of this study was to investigate if the next-of-kin of patients cared for at the thoracic clinic at Uppsala University hospital, have received information about self-care and how they perceive the information they have been given. METHOD: To investigate this, questionnaires were sent out by mail. MAIN RESULT: Most of the respondent’s states that they have not received enough information but that they consider it important to get information. Those who state that they have been given information say that they are pleased with the information received.  CONCLUSION: A tendency in the results shows that the information that is given at the clinic is satisfying, but that not everybody receive it. There is also shown that the next-of-kin’s thinks that it is important to be given information about the patients self-care. / Kortare vårdtider ökar behovet av en välfungerande posthospital eftervård. Närstående är ofta inblandade i patientens egenvård i hemmet och har stort behov av information inför utskrivning. Detta behov är ofta inte tillfredställt. Syftet med denna studie var att undersöka om närstående till patienter på thoraxkliniken vid Akademiska sjukhuset i Uppsala, anser sig ha fått information inför utskrivning och hur de uppfattar den. METOD: För att undersöka detta skickades studiespecifika enkäter ut per post. HUVUDRESULTAT: De flesta svarar att de inte fått tillräckligt med information men att de tycker det är viktigt med information. De som anger att de fått information är generellt nöjda med den information de fått. SLUTSATS: Resultaten tyder på att den information som ges på kliniken är bra men att inte alla får ta del av den samt att de närstående anser att det är viktigt att få information om patientens egenvård.

Emergency Department (ED) congestion can be better understood by examining overall system impacts, in particular inpatient admissions and discharges. This study first investigates trends of inpatient admissions, volume of patients in the ED who have been admitted (ED “boarders”), length of stay, and bed resources of three major admitting services at our teaching institution. It was found that patients admitted to the General Internal Medicine (GIM) service constituted the majority of ED boarders by default rather than design, as GIM served as a safety net for specialty services. This study investigates operational factors that impact discharge and found that day of the week and holidays followed by team organization and scheduling are significant predictors of daily variation in discharge rates. Based on these results, next, a system dynamics computer simulation was built to test the impact of various discharge smoothing strategies on the number of ED boarders. Next, this study uses the framework and tools of system dynamics methodology to design a conceptual model of the ED boarder problem that may be used as a generalizable roadmap to create sustainable improvements in ED congestion. Finally, this study introduces a novel real time metric of hospital operational discharge efficiency- daily discharge rate – to bring focus on the underlying causes of discharge variation and help indicate opportunities for improvement.

Emergency Department (ED) congestion can be better understood by examining overall system impacts, in particular inpatient admissions and discharges. This study first investigates trends of inpatient admissions, volume of patients in the ED who have been admitted (ED “boarders”), length of stay, and bed resources of three major admitting services at our teaching institution. It was found that patients admitted to the General Internal Medicine (GIM) service constituted the majority of ED boarders by default rather than design, as GIM served as a safety net for specialty services. This study investigates operational factors that impact discharge and found that day of the week and holidays followed by team organization and scheduling are significant predictors of daily variation in discharge rates. Based on these results, next, a system dynamics computer simulation was built to test the impact of various discharge smoothing strategies on the number of ED boarders. Next, this study uses the framework and tools of system dynamics methodology to design a conceptual model of the ED boarder problem that may be used as a generalizable roadmap to create sustainable improvements in ED congestion. Finally, this study introduces a novel real time metric of hospital operational discharge efficiency- daily discharge rate – to bring focus on the underlying causes of discharge variation and help indicate opportunities for improvement.

The purpose of this study was to explore the experiences and needs of families during the admission of a child to a paediatric ward in an acute care hospital. Qualitative research methods were used to access the caregivers' and professionals' perceptions of the culture that families experience in a paediatric in-patient setting. For this project, data collection methods included a review of the literature in the area, individual interviews with caregivers, and focus groups with paediatric health care professionals. / In the study, both parents and paediatric professionals described a multitude of experiences and needs of families during a child's admission to a paediatric ward in an acute care setting. Understanding the experiences and needs of families is important for professionals. The information collected in this study provides some insight into the culture that families experience when their child is admitted to a paediatric ward in an acute care hospital.

The mass production of carbon nanotubes (CNTs) by a cost effective process is still a challenge for further research and application of CNTs. This research focussed on the deposition of CNTs on a continuously-fed carbon substrate via arc discharge at atmospheric pressure. In this work, modifications, control and optimization of the available arc-discharge reactor were conducted. New reactor support and new tape feeding mechanisms were added to the reactor for better temperature assessment, longer operating period and better control of the speed of the tape. The influence of inter-electrode gap, substrate velocity and arc current on the surface temperature were investigated. Multiwalled carbon nanotubes (MWNTs) were produced at lower currents (< 20 A) and at larger inter-electrode gaps. Further investigation shows that inter-electrode gap influenced both the arc characteristic and the anode surface temperature (Ts). Here, Ts was measured by an optical pyrometer. The inter-electrode gap was found to indirectly affect the formation of NTs. Anode surface temperature (Ts) varied with gap, reaching a minimum at an intermediate gap. Higher CNTs yield was found at this lowest Ts. This minimum Ts is consistent with the presence of a cloud of nanoparticles ejected by the heated graphite/carbon surfaces. These graphene fragments are thought to later fold and form nanotube “seeds” and then develop into multiwall nanotubes. This cloud of nanoparticles also may affect the electrical conductivity at the front of the anode. Simulation of the arc behaviour, i.e. temperature distributions and flow properties of the plasma, using a computer package Comsol Multiphysics 3.2, was stable only when the electrical conductivity of a dusty plasma near to the electrodes was included. Our experiments show that carbon nanotubes grew better at a Ts range of ~ 3650 K - 3700 K and at the tape speed of 3 mm/s. The results from our work also strongly suggested that tiny carbon crystallites are the main intermediates for CNT growth in an electric arc. The limiting factor for a solid state growth mechanism, therefore, is high temperature annealing of carbon or graphene fragments. Further work should aim to understand the growth mechanism of CNTs, produce comprehensive analysis on the arc plasma composition and also explore the possibility of producing CNTs at higher rates.

This thesis studies the self-discharge performance of recently developed rechargeable hybrid aqueous batteries, using LiMn2O4 as a cathode and Zinc as an anode. It is shown through a variety of electrochemical and ex-situ analytical techniques that many parts of the composite cathode play important roles on the self-discharge of the battery. It was determined that the current collector must be passive towards corrosion, and polyethylene was identified as the best option for this application. The effect of amount and type of conductive agent was also investigated, with low surface area carbonaceous material giving best performances. It was also shown that the state of charge has strong effects on the extension of self-discharge. More importantly, this study shows that the self-discharge mechanism in the ReHAB system involves the cathode active material and contains a reversible and an irreversible part. The reversible portion is predominant and is due to lithium re-intercalation into the LiMn2O4 spinel framework, and results from Zn dissolution into the electrolyte, which drives the Li+ ions out of the solution. The irreversible portion of the self-discharge occurs as a result of the decomposition of the LiMn2O4 material in the presence of the acidic electrolyte, and is much less extensive than the reversible process.

Corona discharge is one of the crucial problems related with high-voltage equipment. This paper focuses on the physical and numerical modelling of corona discharge in an Electrostatic precipitator (ESP). The model is based on Maxwells equations and the Finite element method (FEM) and is implemented with the COMSOL Multiphysics software.The simulation allows studying the electric charge distribution and the behaviour of the electric field inside the ESP. The work is focused primarily on time-dependent studies of the corona discharge.