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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.
31

Att leva med en sjöfarare : En kvalitativ studie ur partnerns perspektiv

Alsterlind, Stina January 2013 (has links)
Ett yrke till sjöss innebär växelvisa borta/hemma perioder vilket innebär en speciell situation för sjöfararen när det gäller att förena yrke och familjeliv. Detta avlösningssystem kan även antas få konsekvenser för den som lever tillsammans med en sjöfarare. Mot denna bakgrund var syftet med denna undersökning att belysa på vilket sätt avlösningssystemet kan påverka partners vardag och relationen till sjöfararen. Undersöknigen omfattar fem semistrukturerade intervjuer med fem kvinnor till svenska sjöfarare. En kvalitativ medtod användes eftersom jag ville förstå och beskriva respondenten personliga upplevelser och erfarenheter. resultatet visade att upplevelsen bland respondenterna verierade. De problematiska aspekter som framgick var framförallt avsaknad av exakta datum för när sjöfararen skulle mönstra på och av sitt fartyg. Man upplevde det svårt att ha framförhållning och kunna göra gemensamma planer eftersom datum ofta ändrades. De positiva aspekterna som framhölls var bland annat; kvalitetstid tillsammans, egen tid och naturliga pauser i förhållandet vilket kunde tillföra positiva känslor av förnyelse. Nyckeln till att få förhållandet att fungera ansågs vara en positiv inställning och ett gemensamt kompromissande från båda parter. / A profession at sea involves alternating away/home periods, which means a special situation for the seafarer in reconciling profession and family life. This rotation system can also be assumed to have consequences fot those who live with a seafarer. Against this backgrund, the purpose of this study was to illustrate how the rotation system may effect the partners´daily lives ande thier ralationship with the saefarer. A qualitaive approach was used because I wanted to understand and describe the respondents´personal experiences. The results showed that the perception among the respondents varied. The problematic aspects that emerged were above all the absence of acxact dates for the serfarer to sign on and off the vessel. Thay found it difficult to be proactive and make common plans when the dates often changed. The positive aspects that were highlighted included; quality time together, own time and natural breakes in the realtionship which could lead to positive emotions of renewal. The key to getting the relationship to work was seen as a positive attitude and a common compromise from both parties.
32

Dynamic Responses of the High Speed Gear Cam Systems

Lao, Yuan-syun 18 July 2008 (has links)
Abstract The gear-cam intermittent mechanism, mainly made up by cam, the sun gear, planet gear and planetary shelf , it has been used in automatically high speed die cutting and creasing machine. The main function of die cutting and creasing machine is cutting and creasing the cardboard, and through compounding the cam motion curves, it will can control the intermittent motion of a gear-cam intermittent mechanism and improve its dynamic characteristic. The effects of gear cam profile and driving speed on the dynamic responses of a box folding and die cutting machine are studied in this work. The input driving motor¡Bgear¡Bgear-cam and output chain mechanics are included in the dynamic system. The equation of motion of the whole system in derived by employing Lagrange¡¦s equation the 4th order Runge-Kutta method is used to simulation the fine domain response of the nonlinear equation of motion. The effect of cam profile, and driving speed on the system dynamic response have been simulated and analysed in the work.
33

Analysis and Motion Curve Synthesis of Cam-Gear Intermittent Mechanisms

Hsu, Hsien-wen 25 July 2008 (has links)
The aim of the research is the analysis and motion curve synthesis for cam-gear intermittent mechanisms. Based on the grooved-cam-controlled motion of rocker planet gear and motion superposition of the planet gear trains, cam-gear intermittent mechanisms transfer continuous rotation to intermittent rotation. Interpolation of non-parametric rational B-splines motion curve is first introduced in this thesis, and it provides better motion characteristics. Based on rigid body transformation, the analytical grooved cam profile can be determined, and the pressure angle and radius of curvature can be calculated. By applying vector operation, rigid body dynamic analysis is also performed. An application example for cam-gear intermittent mechanisms used in the paper delivery system of the die cutting and creasing machine is served to support the content of this research and to improve the kinematic and dynamic characteristics of the paper delivery system.
34

Design of an Intermittent Gear Cam Mechanism

Huang, Chih-wei 06 August 2009 (has links)
Intermittent Mechanisms are widely used in automation equipment, including delivery, assembly, and indexing systems. The aim of this research is to set up a systematic design and analysis procedure of a conjugate intermittent gear cam mechanism. The output of a conjugate intermittent gear cam mechanism is the intermittent motion of sun gear, which has a dwell function in a working period. The intermittent of sun gear is the combination of carrier constant rotation and planet gear variable rotation that is influenced by the conjugate cam profiles. This research first is to set up the design and analysis procedure including applications of rational B-splines to synthesis of output intermittent motion curve and the ALM optimization method for motion tuning to meet specific demands. Secondly, for kinematic analysis, the rigid body transformation methos is used to determinate the conjugate cam profiles so that the geometric analysis can be performed. Then, the rigid body dynamic behavior of the mechanism is analyzed. Finally, to verify the usefulness and effectiveness of the developed procedure, it is conducted to design and analyze a real paper conveyor system of a die cutting and creasing machine. The research results obtained in this study have been applied in the industry due to its validation.
35

Flexibilitetens frammarsch, en studie om den intermittenta anställningen

Idrén, Anna-Karin, Mååg, Anna Mååg January 2015 (has links)
Flexible working conditions is used extensively in organizations today as a way to create flexibility for the employer. Recently we’ve been reading in the newspapers that this approach is a growing problem and the EU has warned Sweden twice that abuse of these forms of employment must be stopped. The Government has recently submitted a proposed rule change to reduce the possibility of stacking one temporary contract after another. Borlänge kommun makes themselves more flexible with the intermittent employments. This study aims to examine why infrequent employments, such as the intermittent employment is used and preferred by Borlänge kommun and how it’s perceived by affected employees in the organization. The questions related, besides why the intermittent employment is used by the organization and how its perceived by those involved, also includes the management of intermittent employment and how the organization is handling work contracts. The background information on the employment law implications gives the reader an insight into how the regulatory framework works surrounding the topic. The theory section highlights the main theories about flexibility and its different shapes and perspectives. For the study a qualitative approach is used. A case study with semi-structured interviews was performed. The respondents were employees involved in the staffing of intermittent employees and also members of the staff with an intermittent employment. The results show that the employment and contracts is correctly handled by labour law regulations. This study shows that Borlänge kommun uses intermittent employments extensively, with its 1 320 intermittently employees. If this is abuse, or not, is not clear from the result. The authors discuss, however, if that is the case. The intermittent employment is used mainly because of the great needs. This is because society is changing and the average age is increasing, both by those using the services and the employees. All respondents perceive the intermittent employment as most flexible for the employees. Respondents working in the staffing department say that they are not flexible enough. The intermittent employees’ working today does not cover the great need. Borlänge kommun think that the flexibility should benefit them more and is currently trying to become more flexible. The employees were generally satisfied with their work situation. Some tendencies of insecurity and uncertainty could be inferred from the intermittent employees answers. The author’s conclusions are that flexibility and the intermittent employment contracts mainly benefit the employer and the employees who actively choose this type of work, such as students. This kind of employment affects, however, the society and those who need a secure lifestyle. The necessary permanent contracts are becoming fewer and replaced by precarious and flexible employment conditions. / Flexibla arbetsformer används i dag flitigt i organisationer som ett sätt att skapa flexibilitet för arbetsgivaren. Nyligen har man kunnat läsa i tidningarna att detta arbetssätt är ett växande problem och EU har vid två tillfällen varnat Sverige att missbruk av dessa anställningsformer måste upphöra. Regeringen har i dagarna lagt ett föreslag på ändrade regler för att minska möjligheten att kunna stapla tillfälliga anställningar på varandra. Borlänge kommun gör sig mer flexibla med den intermittenta anställningen. Studien syfte är att undersöka varför den intermittenta anställningen används av Borlänge kommun och hur den upplevs av vissa berörda i organisationen. Frågeställningarna berör förutom, varför den intermittenta anställningen används i organisationen och hur den upplevs av berörda, även hanteringen av den intermittenta anställningen. Bakgrundsinformation om den arbetsrättsliga innebörden ger läsaren en inblick i hur regelverket ser ut kring anställningen och vad som krävs när det gäller avtalshantering. De teorier som används belyser främst teorier om flexibilitetens olika former och perspektiv, då den intermittenta anställningen är en del av den flexibla arbetsmarknaden. För undersökningen användes en kvalitativ metod. En fallstudie med semistrukturerade intervjuer genomfördes. Respondenterna var personal som arbetar med bemanningen av intermittent anställda samt intermittent anställda medarbetare. Denna studie visar att Borlänge kommun använder sig av timanställda i stor utsträckning, med sina 1 320 intermittent anställda. Om detta anses vara ett missbruk eller inte framgår inte av resultatet, författarna diskuterar dock om så är fallet. Resultat visar att anställningen och avtalen kring den intermittenta anställningen hanteras efter arbetsrättens regelverk. Den intermittenta anställningen används främst i kommunen för att behoven är stora. Detta främst på grund av att samhället förändras och medelåldern blir allt högre, både bland brukare och medarbetare. Den intermittenta anställningen upplevs idag av de respondenter som deltagit i undersökning som mest flexibel för arbetstagaren. De respondenter som arbetar på bemanningsavdelningen menar att de idag inte är flexibla nog. De timvikarier som arbetar idag täcker inte det stora behovet. Kommunen vill att flexibiliteten ska gynna arbetsgivaren mer och arbetar idag för att bli mer flexibla, bland annat genom att utöka den numeriska flexibiliteten med hjälp av utvecklade system för intermittenta anställningar. Medarbetarna var överlag nöjda med sin arbetssituation. Vissa tendenser till otrygghet och osäkerhet kunde utläsas ur respondenternas svar. Författarna har dragit slutsatsen att flexibiliteten och den intermittenta anställningen främst gynnar arbetsgivaren och de medarbetare som aktivt väljer denna typ av tjänst, till exempel studenter. Anställningen drabbar dock de som behöver en säker försörjning och samhället i stort. Nödvändiga tillsvidareanställningar blir färre och ersätts av otrygga och flexibla anställningsförhållanden.
36

En energistudie av Grinstad kyrka : Kartläggning av dagens energitillstånd och förslag till energibesparingsåtgärder / An energy study of the church in Grinstad : Mapping of nowdays energysituation and proposal for energy saving actions

Hjalmarsson Nordgren, Mathias, Olvestrand, Maria January 2007 (has links)
Våra kyrkor är en viktig del av samhället, och är en kulturskatt som måste vårdas. Kyrkorna använder dock väldigt mycket energi till uppvärmning varje år. Detta beror på att de flesta av dem är gamla och att energieffektivitet ej varit en prioriterad fråga i deras verksamhet. Grinstad kyrka är en kyrka med hög energianvändning som trots att den endast är uppvärmd vid förrättningar använder lika mycket energi som två medelvillor. Kyrkan är från 1200-talet, är byggd i tegel och värms idag upp av en oljepanna i ett vattenburet system samt några elradiatorer. Det finns planer på att byta ut oljepannan mot närvärme. Syftet med examensarbetet var att undersöka och ge församlingen en inblick i vart den energi som tillförs kyrkan tar vägen, hur mängden tillförd energi kan minskas genom energieffektiviseringsåtgärder samt vilken miljöpåverkan värmekällan i dagens uppvärmningssystem har jämfört med värmekällan i det planerade närvärmenätet. Målet var att svara på följande frågor: •Var sker de största energiförlusterna i kyrkan och hur skall dessa kunna minskas genom energieffektiviseringsåtgärder? •Hur skall kyrkans värmesystem dimensioneras med avseende på kyrkans värmeeffektbehov? •Hur skulle miljöpåverkan till följd av kyrkans uppvärmning förändras vid anslutning till det planerade närvärmenätet. Det värmesystem som ansågs passa Grinstad kyrka bäst var ett vattenburet värmesystem som värmer kyrkan intermittent. Det ansågs även lämpligt att värma upp på 6 timmar från en grundtemperatur av 8°C till en förrättningstemperatur av 18°C. Värmesystemet måste då ha effekten 22,5 kW, vilket är en effekt som är högre än dagens system kan avge. Därför gavs förslaget att komplettera dagens system med kamflänsrör under några av kyrkbänkarna. De största energiförlusterna i kyrkan visade sig vara genom taket och genom att isolera detta kan förlusterna genom det minskas med 85 %. Grundtemperaturen i kyrkan är idag högre än vad som behövs och genom att sänka den 4ºC kan energianvändningen för grundvärmen minskas med 18 %. Bytet från en central oljepanna till biobränsleeldad närvärme skulle leda till att utsläppen av koldioxid och svavel att minska, medan utsläppen från stoft, koloxid och svavel kommer att öka. / Our churches are an important part of the community, and a cultural treasure that need to be preserved. The most of the churches are old and energy efficiency has not been prioritized earlier. Because of that the churches uses a lot of energy for heating each year. The church in Grinstad is a church with high energy usage. It is not frequency used, but in spite of that it uses as much energy for heating as two average hoses. The church was built of brick in the 1300th century. The heating system today consists of a couple of electric radiators and an oil furnace connected to a hot water system. The purpose of this report was to investigate and to give the congregation in Grinstad insights in where the energy supplied to the church disappears, how the amount of energy supplied could be reduced by energy efficiency actions and also which environmental influence the heating system today has compared to the heat source in the planned small district heating system. The aim was to answer these questions: •Where do the greatest energy losses in the church occur and how could these be reduced by energy efficient actions? •How should the heating system in the church be designed depending on the need for effect of heat in the church? •How would the environmental influence change if the church connects to the planned small district heating system? The heating system that was considered to be the most suitable for the church in Grinstad was a heat water system that warms up the church intermittent. If the church is heated up from the ground temperature 8°C to the ceremony temperature 18°C in 6 hours the heating system need to have the effect 22,5 kW. This is a higher effect than the system today can emit, and therefore extra radiators need to be installed. Calculations showed that the greatest energy losses in the church occurred through the roof. By isolating it the losses could be reduced by 85 %. Today the ground temperature is higher than needed. If the ground temperature is decreased with 4ºC, the energy usage for ground heating could be reduced with 18 %. By changing from the oil furnace to biofuel fired small district heating the emission of carbon dioxide and sulphur will decrease, and the emissions of dust, carbon monoxide and volatile organic compounds will increase.
37

New approaches for treatment of acute intermittent porphyria by enzyme substitution and gene therapy : evaluation in vitro and in vivo /

Johansson, Annika, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
38

Sequential compression devices in postoperative urologic patients: an observational trial and survey study on the influence of patient and hospital factors on compliance

Ritsema, David, Watson, Jennifer, Stiteler, Amanda, Nguyen, Mike January 2013 (has links)
BACKGROUND:Sequential compression devices (SCDs) are commonly used for thromboprophylaxis in postoperative patients but compliance is often poor. We investigated causes for noncompliance, examining both hospital and patient related factors.METHODS:100 patients undergoing inpatient urologic surgery were enrolled. All patient had SCD sleeves placed preoperatively. Postoperative observations determined SCD compliance and reasons for non-compliance. Patient demographics, length of stay, inpatient unit type, and surgery type were recorded. At discharge, a patient survey gauged knowledge and attitudes regarding SCDs and bother with SCDs. Statistical analysis was performed to correlate SCD compliance with patient demographics / patient knowledge and attitudes regarding SCDs / and patient self-reported bother with SCDs.RESULTS:Observed overall compliance was 78.6%. The most commonly observed reasons for non-compliance were SCD machines not being initially available on the ward (71% of non-compliant observations on post-operative day 1) and SCD use not being restarted promptly after return to bed (50% of non-compliant observations for entire hospital stay). Mean self-reported bother scores related to SCDs were low, ranging from 1-3 out of 10 for all 12 categories of bother assessed. Patient demographics, knowledge, attitudes and bother with SCD devices were not significantly associated with non-compliance.CONCLUSIONS:Patient self-reported bother with SCD devices was low. Hospital factors, including SCD machine availability and timely restarting of devices by nursing staff when a patient returns to bed, played a greater role in SCD non-compliance than patient factors. Identifying and addressing hospital related causes for poor SCD compliance may improve postoperative urologic patient safety.
39

Bioaccumulation and sub-lethal effects of intermittent and continuous exposure to metals on the marine mussel, Mytilus galloprovincialis

Amachree, Dokuboba January 2014 (has links)
Aquatic organisms experience intermittent exposure to contaminants. The hazard from such discontinuous exposure may not simply be predicted from existing continuous exposure. Little is known about the bioaccumulation responses of shellfish to metals during intermittent compared to the continuous exposure counterparts. This study was designed to compare the bioaccumulation responses of two metals (Cd and Hg) singly (Chapters 3 and 4) or mixtures (Chapters 5 and 6) during continuous and intermittent exposure. Responses were examined using a multi-assay approach in areas of oxidative stress, osmoregulation, haematology and organ pathology. Tissue metal concentrations were highest in the gill and digestive gland for both metals. The linear or curvilinear pattern of accumulation was observed in the continuous exposure. While an alternating temporal uptake and clearance corresponding with the exposure was observed in the gill (Hg alone) and haemolymph (Cd alone) in intermittent profile. At the end, the study shows that accumulation of Hg or Cd was less in the intermittent compared to the continuous exposure for most tissue. Sub-lethal responses during Hg or Cd alone were similar in both regime apart from the severe pathology in the gill (continuous exposure) and inflammation in the digestive gland (intermittent exposure) observed in the Hg alone treatment (Chapter 4). For Hg plus Cd mixture, the additive effect in accumulation was observed in both exposures. Sub-lethal responses during mixtures were not affected in the intermittent. However, an antagonistic interaction was observed in the TBARS during continuous exposures for all tissues apart from the digestive gland. In terms of risk assessment, regulations for the single metals in continuous exposure will be protective for intermittent events at least for adult M.galloprovincialis.
40

Cycling Performance Following Intermittent Hypoxic Training using an Hypoxicator

Bailey, Christopher Mark January 2004 (has links)
Live high - train low altitude camps can enhance endurance power at sea level by 1-2% (Levine & Stray-Gunderson, 1997). More convenient methods to simulate altitude exposure are now available, but their effects on performance are less well characterized. In this study, we investigated intermittent hypoxic training (IHT) using an Hypoxicator, a device that produces oxygen-depleted air that athletes breathe intermittently through masks in a small group at a central venue. Twelve highly-competitive, male cyclists and multi-sport athletes (IHT group) underwent IHT in two, four-week bouts separated by eight weeks. Bout one consisted of 20 one-hour exposures and bout two 18 exposures where normal and low-oxygenated air was breathed in alternating five-minute intervals. The percentage of oxygen inhaled by the subjects was adjusted to produce an oxygen saturation of the blood of 88-92% in the first week of the study, decreasing to 76-80% (equivalent to an altitude of approximately 6000m) in the final week. A control group of 13 similar athletes did not use the Hypoxicator. Performance trials and blood tests were at four-week intervals; there were 3 trials (familiarization and reliability) before use of the Hypoxicator, 3 trials after to determine the effect of simulated altitude, then a second four-week exposure and one more trial. The measures of performance were mean power in a 16-km time trial on a Kingcycle ergometer (IHT group only) and power in a lactate-threshold test at 3 mmol/L above baseline (both groups). The measures from the blood tests were haemoglobin and haematocrit. There was a gradual but erratic improvement in performance in the time trial and lactate threshold tests over the course of the study in both groups, indicating an improvement through training. Relative to the last baseline test (Trial 3), the IHT group showed a 0.6% decrease in mean power over and above the effect of training in the 16-km time trial in Trial 4, nine days after last use of IHT. There was a 0.3% increase in mean power independent of the training effect in Trial 7, after the second round of altitude exposure. Uncertainty in these changes in performance was ±3.5% (95% confidence interval). The changes in lactate threshold in trials 4 and 7 indicate a possible improvement as a result of IHT exposure. Uncertainty in these changes was ±4.0%. There were negligible changes in the haemoglobin and hematocrit of either group at any time. There was small evidence of high responders, who were probably subjects with the DD genotype for the angiotensin converting enzyme gene. The time exposed to IHT had no bearing on performance and there was no evidence "peak" in results at either four or eight weeks after exposure to IHT. In summary, four weeks of IHT exposure probably resulted in a trivial effect on 16-km time-trial performance and the effort-independent measures provided no further clear-cut evidence of a performance improvement.

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