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Tilting trains : Enhanced benefits and strategies for less motion sicknessPersson, Rickard January 2011 (has links)
Carbody tilting is today a mature and inexpensive technology that allows higher train speeds in horizontal curves, thus shortening travel time. This doctoral thesis considers several subjects important for improving the competitiveness of tilting trains compared to non-tilting ones. A technology review is provided as an introduction to tilting trains and the thesis then focuses on enhancing the benefits and strategies for less motion sickness. A tilting train may run about 15% faster in curves than a non-tilting one but the corresponding simulated running time benefit on two Swedish lines is about 10%. The main reason for the difference is that speeds are set on other grounds than cant deficiency at straight track, stations, bridges, etc. The possibility to further enhance tilting trains’ running speed is studied under identified speed limitations due to vehicle-track interaction such as crosswind requirements at high speed curving. About 9% running time may be gained on the Stockholm–Gothenburg (457 km) mainline in Sweden if cant deficiency, top speed, and tractive performance are improved compared with existing tilting trains. Non-tilting high-speed trains are not an option on this line due to the large number of 1,000 m curves. Tilting trains run a greater risk of causing motion sickness than non-tilting trains. Roll velocity and vertical acceleration are the two motion components that show the largest increase, but the amplitudes are lower than those used in laboratory tests that caused motion sickness. Scientists have tried to find models that can describe motion sickness based on one or more motion quantities. The vertical acceleration model shows the highest correlation to motion sickness on trains with active tilt. However, vertical acceleration has a strong correlation to several other motions, which precludes vertical acceleration being pointed out as the principal cause of motion sickness in tilting trains. Further enhanced speeds tend to increase carbody motions even more, which may result in a higher risk of motion sickness. However, means to counteract the increased risk of motion sickness are identified in the present work that can be combined for best effect. Improved tilt control can prevent unnecessary fluctuations in motion sickness related quantities perceived by the passengers. The improved tilt control can also manage the new proposed tilt algorithms for less risk of motion sickness, which constitute one of the main achievements in the present study. Local speed restrictions are another means of avoiding increased peak levels of motion sickness when increasing the overall speed. The improved tilt control and the proposed tilt algorithms have proven to be effective in on-track tests involving more than 100 test subjects. The new tilt algorithms gave carbody motions closer to non-tilting trains. Rather unexpectedly, however, the test case with the largest decrease in tilt gave a greater risk of motion sickness than the two test cases with less reduction in tilt. It is likely that even better results can be achieved by further optimization of the tilt algorithms; the non-linear relation between motions and motion sickness is of particular interest for further study. / QC 20110429
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Motorists´evaluation of road maintenance managementOlsson, Camilla January 2003 (has links)
The road network is extremely valuable. Road Administrationsare expected to invest maintenance funding in a way thatreturns maximum benefit to road users. Cost-benefit analysis isone method to ensure that an adequate return in terms ofbenefits results from committing expenditure. Today,cost-benefit calculations are frequently used as a base fordecision making of investments. The surges for such methods inthe maintenance management sector are increasing. Up to the present, one reason for not analysing costs andbenefits for various maintenance management measures has beenthe lack of knowledge about comfort benefits for road users inquantitative monetary terms. The aim with this thesis is toinvestigate motoristsapprehension of pavementmaintenance management and winter maintenance operations. Thefinal goal is to find out their willingness to pay fordifferent levels of road maintenance management. Those valuescan later be used in cost-benefit calculations and also ineffect models of road maintenance management. Due to the pioneer status of this study, focus groups andin-depth interviews as well as a number of pilot studies havebeen carried out before a main survey with stated choiceexperiments could be designed. These exploratory studies showedthat the interviewees were familiar with the types of roadsurface damage that exist and in many cases mastered the sameterminology as the Road Administration and others. Showingpictures of well-known types of road damage lead to highermonetary valuations of getting better road standard incomparison with just text descriptions. One reason for thatcould be the requisite severness of the damage in order toillustrate a certain road maintenance shortage. The respondentswith the text descriptions could have stated their preferencesfor an, in their own minds, average shortcoming while the groupwith access to photograph of road damage all saw the samesevere damage. Illustrations of different road maintenancestandards make it possible to control the respondentsinterpretation of the maintenance management standard valuatedbut could lead to high monetary estimations. Driving comfort was very important to the interviewees inthe exploratory studies. That was manifested in the pilotstated choice surveys, which resulted in high willingness topay for better pavement management. The main study consisted of two surveys; the first one wasabout pavement maintenance management and was carried out inOctober to November 2000 and the second one took place inFebruary to March 2001 and was about winter maintenanceoperations. Both the pavement and the winter survey includedattitude questions and two stated choice experiments. Theresult showed that the maintenance management status of theroad network was important to car users. For example, the worstpavement damage was roughness; the motorists were willing topay 1.7 SEK (Swedish Crowns) per kilometre to avoid roadsdamaged in their full length. The least harmful damage of thosestudied was cracks; the willingness to pay to avoid that was0.5 SEK per kilometre. For more rapid snow clearance, the carusers were willing to pay 60 to 80 SEK per year for getting theroads cleared from snow one hour earlier than the currentstandard implies. The willingness to pay for driving on bareroads in comparison with snow roads was 0.4 SEK per kilometre.Statistical tests on the models showed that the parametervalueswere well estimated. In the pavement as well as in the winter survey, a clustergroup analysis was performed in order to test the heterogeneityof attitudes and behaviour to road maintenance management. Theanalysis resulted in two separate groups in each survey. Onegroup consisted of drivers who reported to be very influencedby the level of maintenance management regarding chosen speed,joy of driving and so on. The other group reported to be lessinfluenced and had lower acceptance of higher road tax for thepurpose to increase the maintenance management standard.Separate stated choice models revealed that the differences inattitudes could also reflect the respondentswillingnessto pay for higher road maintenance standard. However, thedifferences were only small and the different groupsmonetary valuations were not found to be significantlydifferent from each other. The result of this study, better knowledge aboutmotoristsapprehension of maintenance management, theirattitudes to driving comfort and road standard and theirmonetary valuations of different levels of pavement maintenanceand winter maintenance operations, opens up the possibility tomake cost-benefit analysis of various maintenance managementprojects. The impact of the monetary values found in this studyhas been studied in a limited cost-benefit analysis. <b>Keywords:</b>stated choice, stated preference, valuationsof maintenance management, driving comfort, road standardevaluation
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Dynamic use of the building structure - energy performance and thermal environmentHøseggen, Rasmus Z January 2008 (has links)
The main objectives of this thesis have been to evaluate how, under which premises, and to what extent building thermal mass can contribute to reduce the net energy demand in office buildings. The thesis also assesses the potential thermal environmental benefits of utilizing thermal mass in office buildings, i.e. reduction of temperature peaks, reduction of temperature swings, and the reduction in the number of hours with excessive operative temperatures. This has been done by literature searches, and experimental and analytical assessments. This thesis mainly concerns office buildings in the Norwegian climate. However, the methods used and the results obtained from this work are transferable to other countries with similar climates and building codes. Within the limitations of this thesis and based on the findings from all parts and papers this thesis comprises, it is shown that utilization of thermal mass in office buildings reduces the daytime peak temperature, reduces the diurnal temperature swing, decreases the number of hours with excessive temperatures, and increases the ability of a space to handle daytime heat loads. Exposed thermal mass also contributes to decrease the net cooling demand in buildings. However, thermal mass is found to have only a minor influence on the heating demand in office buildings. The quantity of the achievements is dependent on the amount of exposed thermal mass, night ventilation strategy, and airflow rates. In addition, parameters such as set point temperatures, control ranges, occupancy patterns, daytime ventilation airflow rates, and prevailing convection regimes are influential for the achieved result. The importance of these parameters are quantified and discussed. / Hovedmålene med denne avhandlingen har vært å evaluere hvordan, under hvilke forutsetninger og i hvilken utstrekning termisk masse kan bidra til å redusere netto energibehov i kontorbygninger. Avhandlingen vurderer også hvilke potensielle fordeler termisk masse har for det termiske inneklimaet, dvs. reduksjon av maksimumstemperatur, temperatursvingninger og antall timer med overtemperaturer. Disse undersøkelsene er gjort gjennom søk i litteraturen, feltstudier og analytiske metoder. Avhandlingen omfatter i hovedsak kontorbygninger under norske forhold, men metodene og resultatene er overførbare til andre land med sammenlignbare klimatiske forhold og byggeskikk. Innenfor avgrensningene gjort i avhandlingen og basert funnene i de ulike delene og artiklene avhandlingen består av, er det vist at utnyttelse av termisk masse i kontorbygg bidrar til å redusere netto energibehov. Termisk masse reduserer også maksimumstemperaturen dagtid, demper temperaturvariasjonene over døgnet og reduserer antall timer med overtemperaturer. Utnyttelse av termisk masse bidrar også til at rom kan tåle en høyere intern varmelast enn lette rom uten at dette går ut over den termiske komforten. Termisk masse har imidlertid liten betydning for energibehovet for oppvarming i kontorbygg. Gevinsten med å utnytte termisk masse avhenger av tilgjengeligheten av eksponerte tunge materialer, strategi for nattventilasjon og ventilasjonsluftmengder. I tillegg innvirker parametere som settpunkttemperaturer, dødbånd og kontrollintervaller for ventilasjonen og bruksmønster. Innvirkningen av disse parametrene er diskutert og kvantifisert.
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Hydraulic Power Steering System Design in Road Vehicles : Analysis, Testing and Enhanced FunctionalityRösth, Marcus January 2007 (has links)
Demands for including more functions such as haptic guiding in power steering systems in road vehicles have increased with requirements on new active safety and comfort systems. Active safety systems, which have been proven to have a positive effect on overall vehicle safety, refer to systems that give the driver assistance in more and less critical situations to avoid accidents. Active safety features are going to play an increasingly important roll in future safety strategies; therefore, it is essential that sub systems in road vehicles, such as power steering systems, are adjusted to meet new demands. The traditional Hydraulic Power Assisted Steering, HPAS, system, cannot meet these new demands, due to the control unit's pure hydro-mechanical solution. The Active Pinion concept presented in this thesis is a novel concept for controlling the steering wheel torque in future active safety and comfort applications. The concept, which can be seen as a modular add-on added to a traditional HPAS system, introduces an additional degree of freedom to the control unit. Different control modes used to meet the demands of new functionality applications are presented and tested in a hardware-in-the-loop test rig. This thesis also covers various aspects of hydraulic power assisted steering systems in road vehicles. Power steering is viewed as a dynamic system and is investigated with linear and non-linear modeling techniques. The valve design in terms of area gradient is essential for the function of the HPAS system; therefore, a method involving optimization has been developed to determine the valve characteristic. The method uses static measurements as a base for calculation and optimization; the results are used in both linear and the non-linear models. With the help of the linear model, relevant transfer functions and the underlying control structure of the power steering system have been derived and analyzed. The non-linear model has been used in concept validation of the Active Pinion. Apart from concept validation and controller design of the active pinion, the models have been roven effective to explain dynamic phenomena related to HPAS systems, such as the chattering phenomena and hydraulic lag. / The printed version and the electronic version differ in that the electronic version contains two built in video films (see page 78 and page 89).
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Inneklimatet på ett kontor : Undersökning av inneklimatet vån. G4 stadshuset samt kontor på ÅnghammargatanBerglund, Johan, Malmberg, Kenneth January 2009 (has links)
This report describes an investigation of the indoor climate in two different workspaces. Since we a big part of our lives are staying indoors in artificial environments, and more particularly in our workplaces, we think it would be interesting to do this investigation. The technical solutions for air treatment systems began with simple natural systems without fans and where the thermal rise of the air applied. In modern time is technical air treating systems used to take care of the fresh air supply. This type of units can supply filtered air with the right temperature to the building. Well-functioning ventilation is essential to bring clean fresh air to the room and effectively remove impurities without sound- or draught problems. The indoor climate is relevant for the output capacity. Ability to work is influenced by a few degrees difference. Even the mental capacity is affected by this. Indoor climate with good comfort create the conditions for effective activities. People experience current indoor climate in various ways. In a workplace, some find it too warm while others complain that it is too cold. While odors from perfumes and pollutants may be perceived as very disturbing for example, allergies and children, while others are not affected at all. The office in City Hall is located on the 4th floor of the central Västerås. Surroundings consist of a large city park, a big car park and the city center. The second office is in a big one floored building, about 10 kilometers outside the city, with close links to a heavily busy road and a large parking place. At the sampling and measurement of the different spaces we used three different instruments. A sound meter, a carbon dioxide meter and a comfort meter which measures, operating temperature, humidity and air velocity. All measurements were made during an hour interval with at least one person in the room. We first measured the noise level and concentrations of carbon dioxide in the room, and after that we started comfort meter and collected the questionnaire responses. The result from all measurements is consistent with the questionnaire responses. In the office space that are perceived as dry, cold or warm we measured almost the same results. The experience of a space feels dry line with reality. When cold outdoor air is heated to around 19 degrees it becomes dry, which is normal for the cold seasons.
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Samvete i vården : att möta det moraliska ansvarets rösterDahlqvist, Vera January 2008 (has links)
The overall aim of this thesis is twofold: first, to develop and validate questionnaires that could be used for investigating relationships between perceptions of conscience, moral sensitivity and burnout and second, to describe patterns of self-comfort used to ease stress and illuminate meanings of living with a troubled conscience. The thesis comprises five studies and is based on both quantitative and qualitative data. In study I, a questionnaire was constructed to assess perceptions of conscience; the Perceptions of Conscience Questionnaire (PCQ). This 15 item-questionnaire was distributed to 444 care providers. Statistical analyses of responses showed sufficient distribution and a stable six factor solution congruent with reviewed literature. The six factors were labelled: ‘the voice of authority’, ‘warning signal’, ‘demanding sensitivity’, ‘asset’, ‘burden’ and ‘depending on culture’. The findings suggest that the PCQ is a valid questionnaire. The aim of study II was further development of an existing questionnaire assessing care providers’ moral sensitivity, enabling its use in various care contexts. The revised nine-item questionnaire, the Moral Sensitivity Questionnaire Revised version (MSQ-R), was distributed to 278 care providers with various professional backgrounds. Statistical analyses of responses showed sufficient distribution and a three-factor solution congruent with reviewed literature. The three factors were labelled: ‘sense of moral burden’, ‘sense of moral strength,’ and ‘sense of moral responsibility.’ The findings suggest that MSQ-R is valid for use in various healthcare contexts. In study III, the PCQ, the MSQ-R and the Maslach Burnout Inventory (MBI) were distributed to a population of psychiatric care providers (n=101) to investigate relationships between perceptions of conscience and moral sensitivity and levels of burnout. The hierarchical cluster analysis shows two clusters with Pearson’s r >.50. Cluster A comprising items such as: being sensitive, interpreting and following the voice of conscience that warns us against hurting other or ourselves and developing as human beings was labelled ‘experiencing a sense of moral integrity’. Cluster B comprising items such as: feeling inadequate, doing more than one has strengths for, feeling always responsible, having difficulties to deal with wearing feelings, perceiving that conscience gives wrong signals and express social values, having to deaden one’ conscience, were all related to scores of the MBI subscales emotional exhaustion (EE) and depersonalisation (DP). Cluster B was labelled ‘experiencing a burdening accountability’. The results show that levels of ‘experiencing a burdening accountability’ are closely related to levels of being at risk of burnout. The aim of study IV was to describe patterns of self-comforting measures used to ease stress. The written accounts of 168 care providers and healthcare students were analysed by means of qualitative content analysis. The findings disclose two dimensions: an ability to use early learned measures to take care of oneself (ingression) and an ability to feel intimately related to life, other human beings and universe or God (transcendence). The findings provide valuable knowledge about self-comfort as a coping strategy. The aim of study V was to illuminate meanings of living with a troubled conscience. Ten psychiatric care providers, respondents of study III with various perceptions of conscience were interviewed. The interviews were interpreted using a phenomenological - hermeneutical method. The findings show that one meaning of living with a troubled conscience is being confronted with inadequacy and struggling to view oneself as ‘good enough.’ The comprehensive understanding indicates that inadequacy, both one’s own and that of organization one represents, infuse feelings of shame rather than feelings of guilt. Shame concerns one’s identity and need of reconciliation. Conclusions: The results reveal two ways of encountering a troubled conscience. One is being unable to interpret the ethical demand from a troubled conscience. This is indicated by connections between levels of moral burden and levels of burnout. The other way is being able to interpret the ethical demand and using one’s troubled conscience to develop practical wisdom. This means facing shame of feeling inadequate, reconciling images of the ideal self and self-contempt, and becoming realistic about what one can do. In this process comfort seems to be a mediator of reconciliation.
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The effect of energy recovery on indoor climate, air quality and energy consumption using computer simulationsFauchoux, Melanie 23 June 2006
The main objectives of this thesis are to determine if the addition of an energy wheel in an HVAC system can improve the indoor air relative humidity (RH), and perceived air quality (PAQ), as well as reduce energy consumption. An energy wheel is an air-to-air energy exchanger that transfers heat and moisture between the outdoor air entering and the exhaust air leaving a building. This thesis uses the TRNSYS computer package to model two buildings (an office and a school) in four different cities (Saskatoon, Saskatchewan; Vancouver, British Columbia; Tampa, Florida and Phoenix, Arizona).<p>The results with and without an energy wheel are compared to see if the energy wheel has a significant impact on the RH and PAQ in the buildings. The energy wheel reduces peak RH levels in Tampa, (up to 15% RH), which is a humid climate, but has a smaller effect on the indoor RH in Saskatoon (up to 4% RH) and Phoenix (up to 11% RH), which are dry climates. The energy wheel also reduces the number of people that are dissatisfied with the PAQ within the space by up to 17% in Tampa. <p>The addition of the energy wheel to the HVAC system creates a reduction in the total energy consumed by the HVAC system in Saskatoon, Phoenix and Tampa (2% in each city). There is a significant reduction in the size of the heating equipment in Saskatoon (26%) and in the size of the cooling equipment in Phoenix (18%) and Tampa (17%). A cost analysis shows that the HVAC system including an energy wheel has the least life-cycle costs in these three cities, with savings of up to 6%. In Vancouver, the energy wheel has a negligible impact on the indoor RH, PAQ and energy consumption.
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Ergonomic Evaluation Of School BussesOzdemir, Pinar 01 February 2013 (has links) (PDF)
In this study, perceived comfort and discomfort regarding school busses is assessed with the main focus on students. A total of 149 students and 38 drivers from a private school in Ankara was chosen participated in the study. Two different surveys were conducted on students and drivers separately, in order to assess perceived comfort and discomfort and suitability of the seat design features. Using SPSS Software to analyze the data, factors contributing to safety, driver distraction, perceived discomfort and perceived comfort were investigated. Bus seat comfort is found to be the most influential factor on the general
assessment of bus comfort. Although no evidence of significant discomfort related to specific body parts such as neck, shoulders, back, thigh or legs is found, in-depth analysis revealed that seat features such as seat pan cushion firmness or armrest height are in correlation with
seat comfort.
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Evaluation of a Body Pillow to Aid Pediatric Spinal Fusion RecoveryJoffe, Naomi Eve 14 August 2009 (has links)
Spinal fusion is a surgical procedure used to correct structural spinal damage or abnormalities. Recovery is painful and consists of a minimum 3-day hospital stay. Specific body positioning is necessary for healing but is difficult to maintain due to physical discomfort. The purpose of this study was to use a single-subject multiple baseline design to compare the current practice of using standard hospital pillows to a body-sized pillow for increasing comfort and decreasing pain in pediatric patients recovering from spinal fusion surgery. Four adolescents who had recently undergone spinal fusion surgery served as participants. Outcome measures included self- and nurse-report, heart rate, and requested medication. Three patients found that the BodyPillow® increased their comfort as they recovered from surgery; the fourth reported that he was less comfortable. No changes in pain were reported with the BodyPillow®. Results should help guide medical care and future research regarding pediatric spinal fusion recovery.
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Commodified Anatomies: Disposable Women in Postcolonial Narratives of Sexual Trafficking/AbductionBarberan Reinares, Maria Laura 12 April 2012 (has links)
This dissertation explores postcolonial fiction that reflects the structural situation of a genocidal number of third-world women who are being trafficked for sexual purposes from postcolonial countries into the global north—invariably, gender, class and race play a crucial role in their exploitation. Above all, these women share a systemic disposability and invisibility, as the business relies on the victim’s illegality and criminality to generate maximum revenues. My research suggests that the presence of these abject women is not only recognized by ideological and repressive state apparatuses on every side of the trafficking scheme (in the form of governments, military establishments, juridical systems, transnational corporations, etc.) but is also understood as necessary for the current neoliberal model to thrive undisturbed by ethical imperatives. Beginning with the turn of the twentieth century, then, I analyze sexual slavery transnationally by looking at James Joyce’s “Eveline,” Therese Park’s A Gift of the Emperor, Mahasweta Devi’s “Douloti the Bountiful,” Amma Darko’s Beyond the Horizon, Chris Abani’s Becoming Abigail, and Roberto Bolaño’s 2666, concentrating on the political, economic, and social discourses in which the narratives are immersed through the lens of Marxist, feminist, and postcolonial theory. By interrogating these postcolonial narratives, my project reexamines the sex slave-trafficker-consumer triad in order to determine the effect of each party’s presence or absence from the text and the implications in terms of the discourses their representations may tacitly legitimize. At the same time, this work investigates the type of postcolonial stories the West privileges and the reasons, and the subjective role postcolonial theory plays in overcoming subaltern women’s exploitation within the current neocolonial context. Overall, I interrogate the role postcolonial literature plays as a means of achieving (or not) social change, analyze the purpose of artists in representing exploitative situations, identify the type of engagement readers have with these characters, and seek to understand audiences’ response to such literature. I look at authors who have attempted to discover fruitful avenues of expression for third-world women, who, despite increasingly constituting the bulk of the work force worldwide, continue to be exploited and, in the case of sex trafficking, brutally violated.
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