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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.
121

Simulação de ride primário e secundário através do uso de carregamento de pista / Primary and secondary ride simulations using road loads time histories

Duarte, Murilo Del Rio 28 October 2010 (has links)
A capacidade de simulação nos atributos de dinâmica veicular tem crescido nos últimos anos, especialmente para os atributos de handling (manobrabilidade e estabilidade) e steering (dirigibilidade). Entretanto, as simulações de ride (em especial dos fenômenos de ride secundário) continuam muito dependentes de modelos sofisticados de pneus. Tais modelos devem ser capazes de simular fenômenos de freqüência mais alta tais como impacto e transmissibilidade de aspereza em três direções. Este trabalho apresenta uma abordagem semi-analítica para o problema de simulação de fenômenos de ride, através do uso de dados de medição em pista gerados através de transdutores de força (wheel force transducers, WFTs). Tais transdutores são tipicamente usados para fins de cascateamento de cargas e durabilidade. Através do uso de tais carregamentos, é possível simular fenômenos de ride em toda a faixa de frequência de estudo (até 8 Hz para ride primário e até 100 Hz para ride secundário) sem a necessidade de um modelo específico de pneu. Usando um modelo de veículo completo construído no software ADAMS, são apresentados dados de correlação com o veículo real e um estudo de caso através da alteração de propriedades de elementos tais como amortecedores, coxins e buchas de suspensão. / Vehicle dynamics CAE capabilities has increased in the past few years, specially, for handling and steering attributes. However, secondary ride simulations are still highly depended on the tire model. Such tire model must be capable to simulate high order phenomenon such as impact and harshness transmissibility in three directions. This dissertation presents a semi-analytical approach to the ride phenomena simulation problem, using data gathered via wheel force transducers (WFTs) that are typically used for load cascading and durability purposes. Using such load histories, it becomes possible to simulate ride phenomena through the whole typical ride frequency range (up to 8 Hz for primary ride and up to 100 Hz for secondary ride) without the necessity of using a special tire model. The results obtained from this approach using a complete car model developed using ADAMS software showed a very good correlation between measured data and simulations. Then on this work a case study using different properties for components such as shock abosrbers, engine mounts and suspension bushings is conducted in order to show the method\'s potential for ride optimization.
122

Subcoberturas: aplicação de isolantes térmicos em sistemas de coberturas / not available

Carletto, Consuelo 20 May 2005 (has links)
Este trabalho tem como foco principal apresentar os resultados e as contribuições da pesquisa experimental comparativa de subcoberturas em sistemas de cobertura. Para tal fim foram utilizados quatro protótipos localizados no canteiro experimental do CRHEA - EESC em São Carlos, São Paulo. Os protótipos foram construídos da mesma forma e com os mesmos materiais: tijolo comum, laje cerâmica recapeada com concreto; cobertos com telhas de fibrocimento e submetidos às mesmas excitações de clima ao ar livre. A análise foi feita aplicando um curto intervalo de clima, com respaldo teórico da climatologia dinâmica. Um dos protótipos serviu como testemunho e não recebeu a instalação de nenhuma subcobertura. Os outros três receberam cada um, respectivamente, subcobertura de foil (isolante por reflexão, ou barreira de radiação), lã de rocha (isolante convencional, condutividade térmica k) e de caixas cartonadas Tetra Pak, um resíduo, como isolante por reflexão e câmara de ar, já que foram utilizadas fechadas e uma ao lado da outra. Foram monitoradas as temperaturas superficiais da telha e da laje e, das temperaturas de bulbo seco no ático e na parte interna dos protótipos a 1,10 m de altura. As medidas de aquisições de dados foram feitas através de CR10X Campbell Scientific automático com medições em 30 segundos, armazenados e totalizados em 30 minutos, o que resultou em valores de clima ao livre e em recinto fechado muito precisos. / Thermal comfort achievement can be done by using thermal reflexive barriers, meaning energy savings and avoiding health problems of air conditioning. It can also be done by using building construction waste materials as Tetra Pak boxes, a low cost reflexive insulation, and applying an industrial \"foil\" which the same effect on reducing indoor air temperatures. In the same way traditional thermal insulation materials were used on this research as the mineral wool (conventional insulation material, thermal conductivity - k values). The analysis was made applying short intervals of climate such as recommended by the dynamic climatic approach. The use of foil insulation can be justified because of its behavior as a reflective barrier and because it has a lot of acceptation; mineral wool (mineral source with low k insulation values) for being a traditional kind of thermal insulation and the Tetra Pak box, because it is a reflective insulation and also because of its waste recycle usage characteristic. The research shows the insulation thermal efficiency applied on three kinds of fiber asbestos cover system, which makes the indoor air temperatures inside of comfort zones values, as intended to expose by graphics, made by real time and automatic experimental measurements. The measurements of data acquisitions were made by automatic CR10X Campbell Scientific Inc., 30 seconds scanner and totalized storage as 30 minutes average intervals. This means a very accurate result of values of outdoor and indoor climate translated by indoor and out door air temperatures.
123

Patients’ Perceptions of Patient-Centered Care and the Hospital Experience Pre- and Post-Discharge

Smith, Cheryl 01 May 2018 (has links)
Florence Nightingale used the principles of patient-centered care as the foundation for nursing practice. Today, patient-centered care delivery is part of the healthcare reform process that extends interprofessionally throughout all settings of healthcare in the United States (U.S.). Patient satisfaction measurement is one primary determinant of effective patient-centered care. The standardized Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey and methods is a nation-wide tool used to measure patient satisfaction. However, this method of patient satisfaction assessment relies on recollections of patients’ hospital experiences and requires accurate memory and recall. This study sought to examine the effect of the memory-experience gap on patients’ perceptions of their hospital experiences and address this research question: Are there any statistical differences between in-hospital and two-week post-discharge perceptions of patient-centered care as measured with HCAHPS patient satisfaction ratings on (a) the composite scores for communication with nurses, communication with physicians, communication about medicines, pain management, staff responsiveness, (b) the individual scores for the hospital environment’s cleanliness and quietness, and the inclusion of patient and family preferences in the plan of care, and (c) the overall global rating score? The design was a non-experimental, prospective, descriptive correlational study. The setting was a 255-bed regional hospital that serves individuals from eight surrounding rural counties in southern middle Tennessee. The case-mix contained diverse individuals with multiple economic, environmental, physical, social and spiritual dynamics. A convenience sample of 82 adult patients ages 26 - 93 represented mainly Caucasian females with mostly cardiovascular and respiratory illnesses who had a minimum one-day stay.
124

Carbody and Passengers in Rail Vehicle Dynamics

Carlbom, Pelle January 2000 (has links)
The carbody plays an important role in rail vehicle dynamics.This thesis aims atdeveloping validated modelling methods tostudy its dynamics, how it is excited on trackand how itinteracts with the passengers. The primary interest is ridecomfort,considering vibrations up to 20 Hz. In this frequencyrange, the structural flexibility ofthe carbody is of majorconcern. The models are intended for use intime-domainsimulation, calling for small-sized models to reducecomputational time and costs. Keyparameters are proposed toselect carbody eigenmodes for inclusion in a flexiblemultibodymodel, and to quantify the interaction between passengers andcarbody. Extensive comparisons between measurements and correspondingsimulations arecarried out in a case study. On-track measurementsare performed to obtain operatingdeflection shapes and powerspectral densities of the accelerations in the carbody.Thecomplete vehicle is modelled using the pieces of softwareGENSYS (flexible multibodymodel) and ANSYS (finite element modelof the carbody). Actual, measured trackirregularities are used asinput. In order to investigate the influence of passengerload,experimental modal analysis of the carbody is performed withand without passengers.Also, amplitude dependence is examined.Simple models, based on human-body modelsfrom literature, of thepassenger-carbody system are proposed and validated.Verticalseating dynamics is considered. The models areimplemented and tested in the casestudy. Finally, ideas on modelreduction and approximation are presented and applied. The main conclusions drawn from the study are that     the structural flexibility of the carbody must be takeninto account when predictingvertical vibration comfort. It ispossible to predict which carbody modes that willcontributemost to the vibrations.     the carbody dynamical properties depend on the excitationamplitude.     passengers and carbody interact significantly.- theproposed models describe the interaction quite well. Theproposed passenger-carbodymodel gives an upper boundary on theinteraction.     the proposed passenger-seat-carbody model can be used tostudy the influence of theseat parameters on the interaction.This merits to be investigated further, however. <b>Keywords</b>: Carbody, Experimental modal analysis, Human-bodydynamics, Modelreduction, Multibody dynamics, Operatingdeflection shapes, Rail-vehicle dynamics,Ride comfort, Seatingdynamics, Structural dynamics.
125

Emotional Effects Of Car Passenger Activities On Physiology And Comfort: An Empirical Study

Kruithof, Aernout 01 November 2012 (has links) (PDF)
There are lots of elements involved in the design of a car. This study, which is inspired by the brief of BMW group, explores the seating unit of cars with regard to prototypical activities, such as, listening to music, working, looking outside etc. The current study proposes that these external stimuli have an effect on comfort experience and felt emotions. So, this study explores the relationship between types of music and activities typically performed by car passengers and emotion and comfort perception, through performing a within subject design empirical study. A car seat provided by BMW group was used to test the above mentioned relationships. Data was collected through a self-report questionnaire, heart rate equipment, a pressure mat and analyzed separately for each condition. Results of the study show that there is a successful emotion induction by task and music individually, and partly on task*music interaction. A comparison of congruent and non-congruent situations, i.e. high arousal music and high arousal task or low arousal music and low arousal task, showed that differences occur in subjects&rsquo / reported level of arousal. Furthermore, the results of the study indicated that comfort is related to valance factors, independent of arousal levels. Lastly, physiological measurements showed that only task has a significant effect on heart rate, implicating for the complexity of linking physiological data to emotion and comfort.
126

Multi-zone modeling of Thermal Comfort and Energy Consumption of a hospital ward : a summer case study

Xie, Tian January 2010 (has links)
Hospital is of interest when consider its especial function. Because of the obviously different between the normal residential buildings, the requirement of hospitals’ indoor climate strictly differs from other buildings. The author starts this report by briefly stating the building construction currently. Surrounded the topic of thermal comfort and energy consumption, many suggestion and options came out in this report to develop a better condition. Firstly, the introduction of the hospital buildings requires the background of the hospital object and the purpose to this report will be stated. Secondly, the simulation tool and how to use this tool simulate our real case are introduced. Then, the summer case is investigated by this tool after the model is proved to be validated. Finally, the improvement of establishing a better indoor environment is raised and the results of improvement and conclusion can be found. The final result will show the optimal solution that discovered by this study after compared different alternatives carefully.
127

CEMA: Comfort Control and Energy Management Algorithms for Use in Residential Spaces Through Wireless Sensor Networks

Henry, Rami F.Z. 26 August 2010 (has links)
In recent years, many strides have been achieved in the area of Wireless Sensor Networks (WSNs), which is leading to constant innovations in the types of applications that WSNs can support. Much advancement has also been achieved in the area of smart homes, enabling its occupants to manually and easily control their utility expenses. In this thesis, both areas of research will be colluded for a simple, yet critical application: efficient and economical comfort control in smart residential spaces. The goal is to design a central, modular energy consumption control system for residential spaces, which manages energy consumption in all aspects of a typical residence. This thesis is concerned with two facets of energy consumption in residences. The first facet is concerned with controlling when the heating, ventilating, and air conditioning unit (HVAC) operates for each room separately. This is in contrast to a typical HVAC system where comfort is provided across the floor as a whole. The second facet is concerned with controlling the lighting in each room so as to not exceed a certain input value. The communication network that supports the realization of these coveted goals is based on Zigbee interconnected sensor nodes which pour data unto a smart thermostat which does all the required calculations and activates the modules required for comfort control and energy management, if needed. A Java-based discrete event simulator is then written up to simulate a floor of a typical Canadian single-family dwelling. The simulation assumes error-less communication and proceeds to record certain room variables and the ongoing cost of operation periodically. These results from the simulator are compared to the results of the well known simulator, created by DesignBuilder, which describes typical home conditions. The conclusion from this analysis is that the Comfort Control and Energy Management Algorithms (CEMA) are feasible, and that their implementation incurs significant monetary savings.
128

Revision av verkligt-värde värderingar : Upplevda osäkerheter samt revisionsåtgärder

Lundgren, Tobias, Paulsson, Erik January 2012 (has links)
Bakgrund och problematisering: Till följd av ökad globalisering, datatillgänglighet och ökade möjligheter för informationsbehandling, är det nuvarande redovisningssystemet under förändring. Redovisningen går från att baseras på den mer traditionella industriella ekonomin till att anpassas mot en mer informationsbaserad ekonomi med större fokus på relevans i årsredovisningarna. Detta innebär ökad användning av värdering till verkligt värde snarare än värdering till anskaffningsvärden, vilket skapar nya utmaningar för revisorer i verifieringen av de finansiella rapporterna då osäkerheter kan uppstå angående verkliga värdens rimlighet. Syfte och frågeställningar: Genom tillämpning av verkligt värde-värdering har en ökad osäkerhet uppstått i de finansiella rapporterna. Dessa osäkerheter kan vara svåra att minska om värderingarna bygger på svårverifierbar data. Studien ämnar ge en ökad förståelse kring hur revisorer upplever de osäkerheter som uppstår vid revision av poster värderade till verkligt värde, samt hur dessa osäkerheter hanteras. Teori: Studiens teoretiska ramverk bygger på  Pentlands (1993) och Carrington &amp; Catasús (2007) tolkning av trygghetsteorin i en revisionskontext. Pentland (1993) gör en tolkning av Collins (1981)  teori om rituella interaktionskedjor och applicerar denna i en revisionskontext. Carringston &amp; Catasús (2007) studerar hur revisorer upplever själva “källan” av trygghet utifrån Kolcaba &amp; Kolcabas (1991) trygghetsteori.  Studiens teoretiska perspektiv grundar sig i dessa två teoretiska utgångspunkter för att tolka och analysera den insamlade empirin. Metod: Studiens tillvägagångssätt bygger på en kvalitativ metod där den insamlade empirin utgörs av nio intervjuer med revisorer verksamma inom de fyra stora revisionsbyråerna. Uppsatsen har en hermeneutisk vetenskapssyn vilket innebär att den insamlade empirin tolkas utifrån de valda teorierna för att på sådant sätt öka förståelsen för hur de intervjuade revisorerna upplever och handskas med osäkerheter som följer av verkligt värde-värderingar.  Resultat och slutsatser: Studien finner indikationer på att revisorerna upplever informationsbristen som den främsta källan till osäkerhet. I linje med Pentlands (1993) studie om revision som en trygghetsskapande process, tolkas dessa osäkerheter utgöra en källa för otrygghet hos revisorerna. Studien finner indikationer på att mängden kunskap och erfarenhet revisorn besitter påverkar den upplevda otryggheten i samband med revision av verkligt värde-värderingar. Studien visar också hur revisorer genom interna- och externa värderingsexperter, modeller samt diskussioner inom revisionsteamet och inom revisionsbyrån minskar denna känsla av otrygghet och uppnår det tillstånd då revisorn känner sig trygg med värderingarna.
129

CEMA: Comfort Control and Energy Management Algorithms for Use in Residential Spaces Through Wireless Sensor Networks

Henry, Rami F.Z. 26 August 2010 (has links)
In recent years, many strides have been achieved in the area of Wireless Sensor Networks (WSNs), which is leading to constant innovations in the types of applications that WSNs can support. Much advancement has also been achieved in the area of smart homes, enabling its occupants to manually and easily control their utility expenses. In this thesis, both areas of research will be colluded for a simple, yet critical application: efficient and economical comfort control in smart residential spaces. The goal is to design a central, modular energy consumption control system for residential spaces, which manages energy consumption in all aspects of a typical residence. This thesis is concerned with two facets of energy consumption in residences. The first facet is concerned with controlling when the heating, ventilating, and air conditioning unit (HVAC) operates for each room separately. This is in contrast to a typical HVAC system where comfort is provided across the floor as a whole. The second facet is concerned with controlling the lighting in each room so as to not exceed a certain input value. The communication network that supports the realization of these coveted goals is based on Zigbee interconnected sensor nodes which pour data unto a smart thermostat which does all the required calculations and activates the modules required for comfort control and energy management, if needed. A Java-based discrete event simulator is then written up to simulate a floor of a typical Canadian single-family dwelling. The simulation assumes error-less communication and proceeds to record certain room variables and the ongoing cost of operation periodically. These results from the simulator are compared to the results of the well known simulator, created by DesignBuilder, which describes typical home conditions. The conclusion from this analysis is that the Comfort Control and Energy Management Algorithms (CEMA) are feasible, and that their implementation incurs significant monetary savings.
130

Tracing the Historical Indoor Climate of a Swedish Church, c. 1800-2000

Legnér, Mattias January 2012 (has links)
Kulturarvet och komforten: Frågan om lämpligt inomhusklimat i kulturhistoriska byggnader under 1900-talet

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