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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Submerged Thin Plate Weirs With Unequal Upstream and Downstream Beds

Nalder, Guinevere Vivianne January 2006 (has links)
This thesis describes a short study to examine the behaviour of submerged flow over a thin plate weir with differing upstream and downstream bed levels i.e. an unequal bed weir as opposed to an equal bed weir where the upstream and downstream beds are at the same level. As submerged weir flow is a function of downstream conditions, it was thought that a lower downstream bed would make submerged flow over the weir easier, This is turn suggested that; The shape of the upstream head (Hu) vs downstream head (Hd) graph would change, being initially more steep in the unequal bed case. The Froude Number of the approaching flow would be lower for the unequal bed weir than for an equal bed weir at the same submergence. Using one of the existing submerged flow formula would lead to an erroneous calculated value. A series of measurements was done on two model weirs of different sizes subject to successive levels of submergence. Analysis of the readings of upstream and downstream heads indicated that the difference in bed levels was significant and the three effects above were noted. The work also suggested a new form of equation to calculate flow over a submerged weir. This was looked at briefly.
212

China Strategy for ESP Wire : A study of the Chinese market from Sandvik's perspective

Eriksson Enquist, Joel January 2008 (has links)
<p>Aim: SMT Wire has noticed that their sales of ESP wire are very low in China compared to India. SMT Wire now wonders how they can increase their market share in China.</p><p>Method: Personal interviews, telephone interviews and interactive conversations.</p><p>Result & Conclusions: SMT Wire should work each tier in the supply chain to gain more orders and increase their market share. It is important to have local representation and work close to the customers so that the customers can feel trust for Sandvik and Sandvik’s employees. The market for spiral discharge electrode material is good in China (the annual consumption is about cccc tonnes) and the market will probably be more and more mature for Sandvik’s high quality materials in a couple of years.</p><p>Suggestions for future research: Is it possible to have a more long-term price on the products on the Asia market? How can Sandvik keep its Chinese personnel? How can the Chinese personnel be trained to make contacting new companies easier for them? How can a foreign company create a guanxi-based selling with a high personnel turnover?</p><p>Contribution of the thesis: A strategy that can be adapted for stainless steel wire companies that want to increase their market share in China.</p>
213

Extended stroke unit service and early supported discharge. : Short and long-term effects

Fjærtoft, Hild January 2005 (has links)
<p>Effekter av utvidet slagbehandling og samarbeid på tvers av forvaltningsnivå.</p><p>Hjerneslag er en av de hyppigste årsaker til alvorlig funksjonshemming og død i Norge, i tillegg at sykdommen medfører betydelige samfunnsmessige kostnader. Forekomsten er ca. 14 000 hjerneslag pr. år, og antallet forventes å øke betraktelig i årene fremover da antall eldre over 65 år vil øke sterkt.</p><p>Det er en stor utfordring å organisere helsetjenesten slik at behandlingstilbudet for denne pasientgruppen blir best mulig. Akuttbehandling i slagenhet er i dag det best dokumenterte behandlingstiltak, men effekten av videre rehabilitering og oppfølging har vært et lite prioritert område for forskning.</p><p>Hovedhensikten med denne avhandlingen har vært å framskaffe mer kunnskap om hva som kan oppnås for slagpasienter ved en systematisk organisering og samarbeid mellom sykehus og primærhelsetjeneste når det gjelder behandling og rehabilitering etter akuttbehandling i slagenhet. Studien som ligger til grunn for avhandlingen ble gjennomført ved Seksjon for hjerneslag, Medisinsk avdeling, St. Olavs Hospital i perioden 1995-1998.</p><p>Intervensjonen var å konstruere en ny behandlingskjede for slagpasienter hvor fokus på bedre samarbeid med primærhelsetjenesten, oppfølging av et ambulerende team, tidlig utreise fra sykehus og rehabilitering med utgangspunkt i hjemmet ble sterkt vektlagt. Den konstruerte behandlingskjeden ble evaluert med tanke på helsegevinst for den enkelte og bedre ressursutnytting sammenlignet med det tradisjonelle behandlingstilbudet.</p><p>Studien ble gjennomført som en klinisk randomisert kontrollert studie der 320 pasienter med akutt hjerneslag ble inkludert. 160 pasienter fikk ordinær slagenhet behandling med videre institusjonsrehabilitering og/eller oppfølging av primærhelsetjenesten, mens de øvrige 160 pasienter fikk oppfølging av et ambulerende team i henhold til den nye og konstruerte behandlingskjeden.</p><p>I de fire arbeidene som inngår i avhandlingen er det sett på risiko for alvorlig funksjonshemning og død, endring i funksjonsnivå og livskvalitet, samt kostnadsanalyser og ressursforbruk av helsetjenester. Pasientene i de to gruppene ble undersøkt og sammenlignet 6 og 12 måneder etter sykdomsdebut.</p><p>Resultatene av studien viste at sammenlignet med tradisjonell behandling oppnådde pasientene i intervensjonsgruppen signifikant bedre funksjonsnivå (p=0.017) og redusert risiko for alvorlig funksjonshemning og død (p=0.044) etter ett år. De viste også tendens til bedret livskvalitet samtidig som initial liggetid i institusjon ble redusert med 40 % (p=0.032). Det var ingen økning i totalt ressursforbruk eller kostnader i intervensjonsgruppen.</p><p>Oppsummert viser avhandlingen at en slagbehandlingskjede med fokus på samarbeid på tvers av forvaltningsnivå, oppfølging av et ambulerende team og rehabilitering mens pasientene bor hjemme gir meget positiv effekt.</p><p>Den kliniske betydning av disse resultater er at en oppfølging i form av en slagbehandlingskjede i tillegg til akutt behandling i slagenhet bør inngå som en integrert del av behandlingstilbudet for denne pasientgruppen.</p><p>Arbeidene er utført ved INM og ISM, Det medisinske fakultet, NTNU. 1.amanuensis, dr.med Bent Indredavik har vært hovedveileder og Professor dr.med Roar Johnsen biveileder.</p> / <p>Extended Stroke Unit Service and Early Supported Discharge. Short and Long-term Effects.</p><p><i>Background and purpose</i></p><p>Stroke imposes a considerable burden for patients, their caregivers and the society worldwide. It is a challenge to organise the healthcare service that can provide effective management of patients who have suffered from stroke. Several trials have shown that stroke unit care improves the outcome for stroke patients. More limited information exists about the most effective way to organise the follow-up care after the acute care in a stroke unit. Stroke patients conventionally receive a substantial part of their rehabilitation in hospital or in other institutions that offer 24 hours-stay.</p><p>The primary aim of this thesis was to increase knowledge about the organising of follow-up care for stroke patients after the acute care in a stroke unit. To achieve this we performed a trial to evaluate the short and long-term effects of an extended stroke unit service (ESUS), with early supported discharge from hospital, co-operation with the primary health care, and more emphasize on rehabilitation at home as essential elements.</p><p><i>Methods</i></p><p>We performed a randomized controlled trial in which 320 acute stroke patients admitted to the Stroke Unit at St. Olavs Hospital, Trondheim University Hospital were included and allocated either to ordinary stroke unit care (OSUS) (160 patients) with further in-patient rehabilitation or follow-up from the primary healthcare service, or to stroke unit care with early supported discharge (160 patients). The ESUS consisted of a mobile team which co-ordinate early supported discharge and further rehabilitation.</p><p>Included in this thesis are 4 papers based on data from this study population of acute stroke patients followed in one year after the onset of stroke. We wanted to compare the groups in relation to independency, quality of life (QoL) and resource use and costs.</p><p>• Functional outcome were measured as the proportion of patients who were independent as assessed by modified Rankin Scale (RS)(RS<2 =global independence) and Barthel Index (BI)(BI>95 = independent in ADL) at 26 weeks and 52 weeks, the differences in final residence and analyses to identify patients who benefited most of an early supported discharge service (paper I and II). All assessments were blinded.</p><p>• The outcome of QoL was measured by the Nottingham Health Profile (NHP) at 52 weeks. Other outcomes measured at 52 weeks were differences between the groups according to social activity, depression, cognitive function and the burden for carers’. (paper III).</p><p>• The use of all health services during the first 52 weeks was recorded prospectively in both groups; its costs were measured as service costs and represent a combination of calculated average costs and tariffs. Hospital expenses were measured as costs per inpatient day. The secondary objectives were to explore differences in costs between the groups with respect to different types of services, time of service delivery and stroke severity (paper IV).</p><p><i>Results</i></p><p>• Extended stroke unit service with early supported discharge and co-ordination by a mobile team improves functional outcome 6 months and 12 months after stroke. The Odds Ratio for independence at one year was 1.56 (95% C.I, 1.01-to 2.44). It was most beneficial for patients with moderate stroke (papers I and II).</p><p>• Extended stroke unit service with early supported discharge can improve long-term quality of life measured by global NHP. The ESUS group had a significant better QoL after one year than the OSUS group (p = 0.048). There were no significant differences between the groups in the secondary outcomes social activity, depression and cognitive function. The caregivers who got their patients early at home did not report an increased burden compared to caregivers whose patients became ordinary stroke unit care (paper III).</p><p>• The length of initial institutional stay (hospital and rehab.clinic) were reduced with 40 % for the patients offered extended stroke unit service (18.6 days in the ESUS versus 31.1 days in the OSUS) (p=0.032). There was also a reduction in average number of total inpatient days during the first year in favour of the ESD group (p = 0.012) (paper IV).</p><p>• The total health services costs for ESUS was equal or less than costs for ordinary care during the first year after stroke. There was a non-significant reduction in total mean service costs in the ESUS group (EUR 18937 / EUR 21824). The service seemed to be most cost effective for patients with moderate severity of stroke (23% lower mean costs compared to OSUS). The important cost savings caused by reduced length of institutional stay did not lead to an increase in costs for home-based rehabilitation (paper IV).</p><p><i>Conclusion</i></p><p>An extended stroke unit service with early supported discharge improved functional outcome and reduced the length of stay in institutions compared to traditional stroke unit care. It also seems that this service can improve long-term quality of life. The costs are equal or less than costs for ordinary care.</p><p>An early, well organised discharge from hospital co-ordinated by a mobile team seems to be an important contribution in the treatment of stroke patients and should be considered, in addition to organised in-patient stroke unit care, as a part of a comprehensive stroke care.</p>
214

High-frequency gas discharge breakdown

January 1951 (has links)
Sanborn C. Brown. / "April 12, 1951." / Bibliography: p. 15. / Army Signal Corps Contract No. W36-039-sc-32037 Project No. 102B. Dept. of the Army Project No. 3-99-10-022.
215

Rotordynamics/discharge water-hammer coupling via seals in pump rotordynamics

Zhang, Kaikai 30 September 2004 (has links)
A new closed-loop frequency-domain model is developed to incorporate the water hammer effect with pump rotordynamics, in order to investigate the sub-synchronous instability problem observed in a field pump. Seal flow-rate perturbations due to eccentricity are calculated from Soulas and San Andres's seal code. A complete transfer function matrix between rotor motion and reaction force due to pressure perturbation is developed in detail. Stability analysis with transfer-function'add-in' modules is conducted in XLTRC2. Seal clearances and the reaction force angle are found to be important in shifting natural frequencies and damping. The sub-synchronous instability observed in field is duplicated successfully with double-clearance seals.
216

Extended stroke unit service and early supported discharge. : Short and long-term effects

Fjærtoft, Hild January 2005 (has links)
Effekter av utvidet slagbehandling og samarbeid på tvers av forvaltningsnivå. Hjerneslag er en av de hyppigste årsaker til alvorlig funksjonshemming og død i Norge, i tillegg at sykdommen medfører betydelige samfunnsmessige kostnader. Forekomsten er ca. 14 000 hjerneslag pr. år, og antallet forventes å øke betraktelig i årene fremover da antall eldre over 65 år vil øke sterkt. Det er en stor utfordring å organisere helsetjenesten slik at behandlingstilbudet for denne pasientgruppen blir best mulig. Akuttbehandling i slagenhet er i dag det best dokumenterte behandlingstiltak, men effekten av videre rehabilitering og oppfølging har vært et lite prioritert område for forskning. Hovedhensikten med denne avhandlingen har vært å framskaffe mer kunnskap om hva som kan oppnås for slagpasienter ved en systematisk organisering og samarbeid mellom sykehus og primærhelsetjeneste når det gjelder behandling og rehabilitering etter akuttbehandling i slagenhet. Studien som ligger til grunn for avhandlingen ble gjennomført ved Seksjon for hjerneslag, Medisinsk avdeling, St. Olavs Hospital i perioden 1995-1998. Intervensjonen var å konstruere en ny behandlingskjede for slagpasienter hvor fokus på bedre samarbeid med primærhelsetjenesten, oppfølging av et ambulerende team, tidlig utreise fra sykehus og rehabilitering med utgangspunkt i hjemmet ble sterkt vektlagt. Den konstruerte behandlingskjeden ble evaluert med tanke på helsegevinst for den enkelte og bedre ressursutnytting sammenlignet med det tradisjonelle behandlingstilbudet. Studien ble gjennomført som en klinisk randomisert kontrollert studie der 320 pasienter med akutt hjerneslag ble inkludert. 160 pasienter fikk ordinær slagenhet behandling med videre institusjonsrehabilitering og/eller oppfølging av primærhelsetjenesten, mens de øvrige 160 pasienter fikk oppfølging av et ambulerende team i henhold til den nye og konstruerte behandlingskjeden. I de fire arbeidene som inngår i avhandlingen er det sett på risiko for alvorlig funksjonshemning og død, endring i funksjonsnivå og livskvalitet, samt kostnadsanalyser og ressursforbruk av helsetjenester. Pasientene i de to gruppene ble undersøkt og sammenlignet 6 og 12 måneder etter sykdomsdebut. Resultatene av studien viste at sammenlignet med tradisjonell behandling oppnådde pasientene i intervensjonsgruppen signifikant bedre funksjonsnivå (p=0.017) og redusert risiko for alvorlig funksjonshemning og død (p=0.044) etter ett år. De viste også tendens til bedret livskvalitet samtidig som initial liggetid i institusjon ble redusert med 40 % (p=0.032). Det var ingen økning i totalt ressursforbruk eller kostnader i intervensjonsgruppen. Oppsummert viser avhandlingen at en slagbehandlingskjede med fokus på samarbeid på tvers av forvaltningsnivå, oppfølging av et ambulerende team og rehabilitering mens pasientene bor hjemme gir meget positiv effekt. Den kliniske betydning av disse resultater er at en oppfølging i form av en slagbehandlingskjede i tillegg til akutt behandling i slagenhet bør inngå som en integrert del av behandlingstilbudet for denne pasientgruppen. Arbeidene er utført ved INM og ISM, Det medisinske fakultet, NTNU. 1.amanuensis, dr.med Bent Indredavik har vært hovedveileder og Professor dr.med Roar Johnsen biveileder. / Extended Stroke Unit Service and Early Supported Discharge. Short and Long-term Effects. Background and purpose Stroke imposes a considerable burden for patients, their caregivers and the society worldwide. It is a challenge to organise the healthcare service that can provide effective management of patients who have suffered from stroke. Several trials have shown that stroke unit care improves the outcome for stroke patients. More limited information exists about the most effective way to organise the follow-up care after the acute care in a stroke unit. Stroke patients conventionally receive a substantial part of their rehabilitation in hospital or in other institutions that offer 24 hours-stay. The primary aim of this thesis was to increase knowledge about the organising of follow-up care for stroke patients after the acute care in a stroke unit. To achieve this we performed a trial to evaluate the short and long-term effects of an extended stroke unit service (ESUS), with early supported discharge from hospital, co-operation with the primary health care, and more emphasize on rehabilitation at home as essential elements. Methods We performed a randomized controlled trial in which 320 acute stroke patients admitted to the Stroke Unit at St. Olavs Hospital, Trondheim University Hospital were included and allocated either to ordinary stroke unit care (OSUS) (160 patients) with further in-patient rehabilitation or follow-up from the primary healthcare service, or to stroke unit care with early supported discharge (160 patients). The ESUS consisted of a mobile team which co-ordinate early supported discharge and further rehabilitation. Included in this thesis are 4 papers based on data from this study population of acute stroke patients followed in one year after the onset of stroke. We wanted to compare the groups in relation to independency, quality of life (QoL) and resource use and costs. • Functional outcome were measured as the proportion of patients who were independent as assessed by modified Rankin Scale (RS)(RS&lt;2 =global independence) and Barthel Index (BI)(BI&gt;95 = independent in ADL) at 26 weeks and 52 weeks, the differences in final residence and analyses to identify patients who benefited most of an early supported discharge service (paper I and II). All assessments were blinded. • The outcome of QoL was measured by the Nottingham Health Profile (NHP) at 52 weeks. Other outcomes measured at 52 weeks were differences between the groups according to social activity, depression, cognitive function and the burden for carers’. (paper III). • The use of all health services during the first 52 weeks was recorded prospectively in both groups; its costs were measured as service costs and represent a combination of calculated average costs and tariffs. Hospital expenses were measured as costs per inpatient day. The secondary objectives were to explore differences in costs between the groups with respect to different types of services, time of service delivery and stroke severity (paper IV). Results • Extended stroke unit service with early supported discharge and co-ordination by a mobile team improves functional outcome 6 months and 12 months after stroke. The Odds Ratio for independence at one year was 1.56 (95% C.I, 1.01-to 2.44). It was most beneficial for patients with moderate stroke (papers I and II). • Extended stroke unit service with early supported discharge can improve long-term quality of life measured by global NHP. The ESUS group had a significant better QoL after one year than the OSUS group (p = 0.048). There were no significant differences between the groups in the secondary outcomes social activity, depression and cognitive function. The caregivers who got their patients early at home did not report an increased burden compared to caregivers whose patients became ordinary stroke unit care (paper III). • The length of initial institutional stay (hospital and rehab.clinic) were reduced with 40 % for the patients offered extended stroke unit service (18.6 days in the ESUS versus 31.1 days in the OSUS) (p=0.032). There was also a reduction in average number of total inpatient days during the first year in favour of the ESD group (p = 0.012) (paper IV). • The total health services costs for ESUS was equal or less than costs for ordinary care during the first year after stroke. There was a non-significant reduction in total mean service costs in the ESUS group (EUR 18937 / EUR 21824). The service seemed to be most cost effective for patients with moderate severity of stroke (23% lower mean costs compared to OSUS). The important cost savings caused by reduced length of institutional stay did not lead to an increase in costs for home-based rehabilitation (paper IV). Conclusion An extended stroke unit service with early supported discharge improved functional outcome and reduced the length of stay in institutions compared to traditional stroke unit care. It also seems that this service can improve long-term quality of life. The costs are equal or less than costs for ordinary care. An early, well organised discharge from hospital co-ordinated by a mobile team seems to be an important contribution in the treatment of stroke patients and should be considered, in addition to organised in-patient stroke unit care, as a part of a comprehensive stroke care.
217

Electrical Insulation Characteristics of HTS Cables Under Quench-Induced Thermal Stress Condition

Hayakawa, N., Ueyama, S., Kojima, H., Endo, F., Masuda, T., Hirose, M. January 2007 (has links)
No description available.
218

Modelización y Fabricación de Dispositivos Supresores TVS para Protección en Aplicaciones de Baja Tensión

Urresti Ibáñez, Jesús Roberto 11 December 2008 (has links)
The contious reduction in size and work voltage of the new generation integrated circuits (ICs) requires the reducction of the thickness of the different layers that make up (especially the gate oxides and levels of isolation between conductors), in order to increase its density and speed of integration, reducing its energy consumption. However, these improvements involve an increase in their sensitivity to external perturbations such as fluctuations in the electricity network, capacitive coupling or electrostatic discharge (ESD). Although there is a wide range of electronic devices designed to protect ICs from such disturbances avoiding destruction (Zener diodes, thyristors, etc.), The continuous reduction of voltage operation and increasing the frequency of work has required a major research effort to adapt the protective devices to the new conditions of operation. The main features that should satisfy any device designed to protect an electronic system are: fast response, low parasitic capacity, driving in low resistance, high absorption capacity of current, low leakage current in reverse, minimum size, low cost, should not interfere in the normal mode of operation of the system that protects and must maintain unchanged its electrical characteristics over time. In high voltage applications, Zener diodes and thyristors are the most used, both in format as a discreet way to the monolithic IC, for protection against ESD phenomena. However, new generations of ICs for mobile applications (portable computers, telecommunications, remote control systems, etc.) Require devices capable of working at low voltage and low energy consumption (in order to maximize the life of batteries ). Under these conditions, the protection of traditional elements are not optimal, so that further protection devices with low voltage and low shooting leakage current in his block state. In this situation, the use of new protective structures based on a process of rupture by emptying (punch-through) improves the characteristics of those based on a break by avalanche (base of the traditional components). Thus, this study aims to analyze, optimize, design and produce new elements of protection by breaking with punch-through, known as Transient Voltage Suppressors (TVS), which improve the performance of Zener diodes in applications from low tension (less than 3 V). Thus, Chapter 1 describes the main electric perturbation and sources that originated, along with a description of its effect on the CIs. It also provides a description of the different existing devices suppressors, with special emphasis on TVS, the main topic for this work. In Chapter 2 presents a study of the vertical TVS based in the punch-through effect, which analyzes the electrical characteristics of its two configurations (TVS 3 layers, TVS 4 layers). It also presents the theoretical model of rupture developed for this type of structures as well as the verification of it through numerical simulations and experimental data. Chapter 3 deals with the design, fabrication and characterization of vertical TVS. We show the technological processes done and the improvements are detailed, demonstrating the superiority of TVS 4 layers respect to the TVS 3 layers and Zener diodes. Chapter 4 presents the first study published on lateral punch-through TVS devices intended to be integrated with the circuitry to protect. The study was conducted for different configurations proposed in technology Bulk Silicon, compared among themselves and choose the configuration that shows better characteristics. This chapter also presents a novel way of using the field plate to reduce the breakdown voltage into the lateral TVS. Finally, and as a line of the future, assessing the feasibility of integrating lateral TVS devices in SOI (Silicon-On-Insulator) substrates. Finally, Chapter 5 shows the manufacturing of lateral TVS. Details the technological process, the design of masks, clean room manufacturing in the characterization and finally, whether technological, using techniques of Reverse Engineering, as electric.
219

Impulse partial discharge characteristics and their mechanisms under non-uniform electric field in N/sub 2//SF/sub 6/ gas mixtures

Hayakawa, Naoki, Yoshitake, Yuichiro, Koshino, Naoto, Ueda, Toshiaki, Okubo, Hitoshi 10 1900 (has links)
No description available.
220

Influence of accumulated surface charges on partial discharge activity at micro gap delamination in epoxy GIS spacer

Okubo, Hitoshi, Mansour, Diaa-Eldin A., Kojima, Hiroki, Hayakawa, Naoki, Endo, Fumihiro 19 July 2009 (has links)
No description available.

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