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Schiele, Yvonne [Verfasser]. "Analyse und Entwicklung von BBr3-Emitterstrukturen für dünne kristalline n-Si-PERT-Solarzellen / Yvonne Schiele". München : Verlag Dr. Hut, 2016. http://d-nb.info/1120764025/34.
Testo completo
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Moreno, Ivan Daniel. "Towards the Investigation of Ultrafast Directed Excite-State Isomerization in BBR3 and PBR3 with sub-50 fs Deep-UV/UV laser pulses". Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1404740168.
Testo completo
3
Slade, Alexander Mason Electrical Engineering UNSW. "Boron tribromide sourced boron diffusions for silicon solar cells". Awarded by:University of New South Wales. Electrical Engineering, 2005. http://handle.unsw.edu.au/1959.4/21850.
Testo completoAbstract (sommario):
This thesis undertakes the development, characterization and optimization of boron diffusion for silicon solar cells. Heavy diffusions (sheet resistance < 40 Ohm/square) to form a back surface field, and light diffusions (sheet resistance > 100 Ohm/square) to form oxide-passivated emitters were developed. Test structures and solar cells were fabricated to assess uniformity, lifetime and recombination effects due to the light and heavy boron diffusions. It was found that the growth of a thin ~200 ??, thermal oxide, during stabilization ??? immediately prior to the boron diffusion - was required to maintain high lifetime and reduce surface recombination (reducing the emitter saturation current density) for all boron diffusions. The heavy boron diffusion process was incorporated into the single side buried contact solar cell processing sequence. The solar cells fabricated had both boron diffused and Al/Si alloyed P+ regions for comparison. This research conclusively showed that boron diffused solar cells had significantly higher open circuit voltage compared to Al/Si alloyed devices. Fabrication of n-type solar cells, and their subsequent characterization by overlayed secondary electron image and the electron beam induced current map showed that the Al/Si alloy varied in depth from 5 to 25 micrometers deep. Methodology and characterization for light, oxide-passivated boron diffusions are also presented. This study yielded boron diffused emitters (sheet resistance > 100 Ohm/square) with low emitter saturation current. It was observed that this was possible only when the thermal oxidation after the boron diffusion was minimal, less than 1,000 ??. This was due to the segregation effect of boron with oxide, decreasing the surface concentration that in turn decreased the electric field repulsion of electrons from the surface. Device modelling of n-type solar cells is presented where the parameters of the modelling include the results of the light, oxide-passivated boron diffusions. This modelling shows n-type-base material with light oxide-passivated boron diffusion has higher potential conversion efficiency than forming a solar cell from phosphorous diffused p-type material.
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Subasi, Nuriye Tuna. "Novel Synthetic Methodologies For Heeocycles As Building Blocks In Drug Synthesis". Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613028/index.pdf.
Testo completoAbstract (sommario):
Nitrogen containing heterocycles have always constituted a subject of great interest due to their wide presence in biologically important compounds so the development of efficient methods for the preparation of pyrrole derivatives and formation of new pyrrole-based heterocyclic compounds are an attractive goal in heterocyclic chemistry. In this study, starting from dimethoxytetrahydrofurane and amino acid esters, unsubstituted pyrrole derivatives, and treatment of amino acid esters with convenient chloroenones 1,2-disubstituted and 1,2,4-trisubstituted pyrrole derivatives were synthesized without racemization. Reaction of unsubstituted pyrrole derivatives with norephedrine toward inter- and intramolecular cyclizations give new interesting heteropolycylic compounds with oxazole-pyrrole-pyrazine structures. Study continued with cyclization reaction of these synthesized substituted and unsubstituted pyrrole derivatives with BBr3 and new bicyclic pyrrole derivatives were obtained in moderate yield.
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Mereshchenko, Andrey S. "ULTRAFAST PHOTOCHEMISTRY OF POLYATOMIC MOLECULES CONTAINING LABILE HALOGEN ATOMS IN SOLUTION". Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1369774991.
Testo completo
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Nilsson, Esposito Anton. "Potentiella förbättringar av BBR". Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-82995.
Testo completoAbstract (sommario):
Boverkets Byggregler, BBR, reglerar hur byggnader får utformas. Regelverket uppdateras med jämna mellanrum för att fortsatt hållas modernt i det förändrande landskapet inom byggindustrin. Rapporten fokuserar på denna förbättringsaspekt och har närmare studerat två regler inom BBR. Dessa är paragraferna 5:561 som innefattar de kriterier som följs vid brandsektionering och 5:61 vilket handlar om att motverka brandspridning mellan byggnader igenom att byggnader kan byggas på 8 meters avstånd. Urvalet av regler gjordes via intervjustudier med sakkunniga inom brandingenjörsverksamheter samt genom litteraturstudier av framförallt Syfteshandboken. För att få en förståelse av styrkor och svagheter inom BBR utfördes litteraturstudier av Modernare byggregler samt Framtidens byggregler. Genom analys av dessa publikationer visades det hur analytisk dimensionering är en positiv och önskvärd metod att bevara, det finns väldigt många olika typer av tillämpare med skilda kunskapsnivåer gällande brandreglerna, samt att det fanns en del missledande passager i BBR som gör det förvirrande för tillämpare att urskilja mellan föreskrift och allmänna råd. Tillämpare som saknar specifik utbildningen eller information gällande byggreglerna har nästintill inga andra alternativ än att hänvisa till experter inom branschen för att tillämpa analytisk dimensionering. Då det vid många tillfällen inte finns möjligheter att följa de allmänna råden och förstå vilka aspekter av föreskriften som ska täckas igenom att tillämpa dem för specifika byggen. Fokus i detta arbete därför varit att undersöka möjlighet till analytisk dimensionering för de utvalda reglerna och sedan ge förslag på förtydliganden och utökade möjligheter för att förenkla för tillämpare av regelverket. Från undersökningen framkom det att föreskrifterna för 5:561 och 5:61 främjar användningen av analytisk dimensionering då de inte innehöll detaljlösningar men det fanns vissa aspekter av de allmänna råden som kunde förbättras. Genom att undersöka historiken gällande reglerna och identifiera anledningarna till tidigare revideringar och syftena bakom dessa revideringar, kunde nya välgrundade förändringsförslag tas fram. Ett av dessa förslag är att öka förståelsen för tillämpare genom att introducera fler förklarande exempel som kan presenteras som en lista till paragraf 5:61 för att lättare förstå vilka gränser och möjligheter som kan appliceras för att upprätthålla lämpligt brandskydd mellan byggnader. För paragraf 5:561 har det vid många tidigare utgåvor av byggreglerna funnits en större tabell med fler val av brandtekniska installationer för att upprätthålla lämpligt brandskydd, medan dagens allmänna råd har en mindre lista med färre valmöjligheter. Detta innebär en reduktion av angivna alternativ och variationer av tillgängliga brandtekniska installationer. Det rekommenderas att återinföra en mer utförlig lista för att utöka valmöjligheter och förståelse för tillgängliga brandtekniska installationer. Rekommendationerna som anges måste testas för att påvisa konsekvenserna och fördelarna ifall dessa träder i kraft. Speciellt gäller detta värmestrålningsberäkningar för listan inom 5:61 sedan brandgasventilering för paragraf 5:561.The focus and goal of the thesis were to establish how and what in the current regulations, BBR, of Boverket (The Swedish National Board of Housing, Building and Planning) should be revised in order to increase understanding or give more choices to the person trying to apply the rules. BBR is today the set of rules used when designing a building. These rules are repeatedly revised in order to be kept up to date with modern building standards. The report applied literature and interview studies in order to identify some of the many different rules in BBR, which was interesting to research further. The chosen rules were 5:561 and 5:61, and by mapping previously made changes and compare today's iterations of the rules to the previous ones, some stark differences between the rules could be noted. In order to know what to be revised in the chosen rules, specific aspects must be identified as beneficial or hampering. For specified aspects to be identified as beneficial and as such being kept for future editions of BBR, also finding what are the adverse aspects of the rules in order to change them. To do this, an analysis of the publications “Modernare byggregler” and “Framtida byggregler” was made. The outcome of this analysis resulted in the strong support for an aspect of the rules called “analytisk dimensionering” (performance-based design). This aspect is the ability for someone trying to apply the rules to be able to make alternative solutions instead of following the given examples. In conclusion, the report found both rules 5:561 and 5:61 to have flaws that could mainly be solved by making the rules easier to follow without opting for “analytisk dimensionering”. This could be achieved with the inclusions of more examples and extending the available options a user of the rules would have. For these changes to be applied correctly more research must be done in these specific applications, in order to reassure what the consequences would be.
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Egerud, Rebecca, e Erik Södergren. "Cost differences between Miljöbyggnad Guld and BBR". Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-142880.
Testo completoAbstract (sommario):
Denna rapport är en jämförelse mellan BBR och Miljöbyggnad nivå Guld. Tre frågeställningar besvaras, Vad är skillanden mellan BBR och Miljöbyggnad nivå guld, vad är mervärdet och merkostnaden av Miljöbyggnad nivå Guld. Studien är utförd på en fallstudie av Studenthuset som byggs på Linköpings Universitet. Resultaten av studien visar att skillanderna mellan de två är stora, mervärdet för Miljöbyggnad nivå Guld är stort samt att merkostnaden är 2.5 - 3.0 % för Miljöbyggnad nivå GUld
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Pretorius, Pamela Reed. "Elucidating a role for BBS3 in syndromic and non-syndromic retinal disease". Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/2760.
Testo completoAbstract (sommario):
Hundreds of individually rare, but collectively common Mendelian disorders result in visual impairment. One of these disorders is a heterogeneous syndromic form of retinal degeneration, Bardet-Biedl Syndrome (BBS). This disease is an autosomal recessive disorder characterized by retinal degeneration, obesity, learning disabilities, congenital anomalies, and an increased incidence of hypertension and diabetes. Typically, individuals with BBS experience vision loss during childhood leading to blindness by the third decade of life. At least fourteen genes (BBS1-BBS14) are reported to individual cause BBS. This thesis focuses on one of these genes, BBS3, with the overall goal of characterizig the function of BBS3 in terms of both syndromic and non-syndromic retinal degeneration using the zebrafish and mouse model systems. A member of the Ras family of small GTP-binding proteins, BBS3 is postulated to play a role in vesicular transport. A second highly conserved transcript of BBS3, BBS3L, has been identified and is expressed predominantly in the mouse and zebrafish eye. The eye-specific expression of BBS3L facilitates the dissection of BBS function in the retina independent of alterations to other tissues. To this end a Bbs3L knockout mouse was generated and histological analysis at 9 months reveals disorganization of the inner segments, indicative of retinal degeneration. To further evaluate the functional effects of BBS3 deficiency in the eye, an antisense oligonucleotide (Morpholino) approach was utilized to knockdown bbs3 gene expression in zebrafish. Consistent with an eye specific role, knockdown of bbs3L results in mislocalization of the photopigment green cone opsin and reduced visual function, but not abnormalities of the Kupffer's vesicle or delays in intracellular trafficking of melanosomes, both cardinal features of BBS in the zebrafish. To dissect the individual functions of BBS3 and BBS3L, in vitro transcribed wild-type human BBS3 or BBS3L RNA was co-injected with the bbs3 morpholinos. BBS3L RNA, but not BBS3 RNA, restores green opsin localization and vision. Moreover, only BBS3 RNA is sufficient to rescue melanosome transport, a cardinal feature of BBS in the zebrafish. Bbs3L knockout mice as well as a zebrafish bbs3 knockdown model demonstrate that BBS3L is both necessary and sufficient for retinal function and organization.
This work was extended to humans by characterizing the A89V missense mutation in BBS3 that results in non-syndromic retinal degeneration. To evaluate the in vivo function of the A89V missense mutation in non-syndromic retinal degeneration and BBS, rescue experiments were performed in the zebrafish. Unlike wild-type BBS3L RNA, BBS3L A89V RNA does not rescue the vision defect seen with loss of bbs3 in zebrafish; however, BBS3 A89V RNA is able to suppress the cardinal zebrafish BBS phenotype of melanosome transport, similar to wild-type BBS3 RNA. These data demonstrate that the BBS3L A89V mutation identified in patients with non-syndromic retinal degeneration is critical and specific for the vision defect.
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Johansson, Jan, e Henrik Karlsson. "Energieffektivt byggnande : Hur kan BBR bidra till ett ”klimatsmart” byggande?" Thesis, Karlstad University, Faculty of Technology and Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-1159.
Testo completoAbstract (sommario):
Byggbranschen står idag för 40 % av landets totala energianvändning varav 85 % av energin förbrukas i bruksskedet. Med hänsyn till den omfattande energianvändningen inom byggsektorn har branschen ett stort ansvar för att minska landets totala energiförbrukning. Teknik för att bygga energisnåla byggnader är långt framme, men används inte i så stor utsträckning som man borde. En anledning till detta kan vara att man bygger med en kortsiktig syn på investeringar och att den som bygger och förvaltar inte är samma part. Verktyg för att ta riktiga beslut ur ett långsiktigt ekonomiskt och miljömässigt perspektiv finns i form av livscykelkostnadskalkyler (LCC). Byggnader har lång livslängd och det är viktigt att man i ett tidigt skede vid projektering använder sig av de hjälpmedel som finns att tillgå.
Koldioxid är en stor bidragande orsak till den ökade växthuseffekten, för att byggbranschen i framtiden skall kunna minska de bidrag den genererar till atmosfären så är det viktigt att man tar fram metoder för hur man på ett riktigt sätt mäter koldioxidutsläpp från byggnader i bruksskedet.
Byggherren har en nyckelroll för vår samhällsutveckling varför det är viktigt att han/hon har kompetens för att fatta riktiga beslut ur ett hållbarhetsperspektiv. Idag kan i princip vem som helst vara byggherre oavsett kompetens.
Ett steg mot ett klimatsmartare byggande vore att ställa krav i Boverkets byggregler på att man vid projektering skall utföra en LCC kalkyl. Ett större individuellt ansvar för de faktiska koldioxidutsläpp som man bidrar med genom de beslut man tar vid en byggnation skulle kunna regleras i BBR genom att man utformade metoder för att mäta de faktiska koldioxidutsläpp en byggnad ger. Ett system med avgifter på de utsläpp man bidrar med skulle säkert medföra att man tänker till ordentligt innan man fattar beslut om hur en byggnad skall utformas. Ett krav på certifiering av landets byggherrar är rimligt med tanke på den betydelse han/hon har för samhällsutvecklingen.
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Bajic, Benjamin, e Alicia Toor. "Stockholm stads krav i Norra Djurgårdsstaden : Jämförelse med BBR, PBL och MB". Thesis, KTH, Byggteknik och design, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233755.
Testo completo
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Sandström, Åke. "En jämförelse mellan Boverkets byggregler och Miljö-byggnad-silver för ett omvårdnadsboende : En studie om det ekonomiska utfallet". Thesis, Uppsala universitet, Fasta tillståndets fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-298471.
Testo completoAbstract (sommario):
The production cost and life cycle cost have been analyzed in this work considering two different building standards for the same building. The standards are Miljöbyggnad silver and Boverket's regulations for buildings. The costs have been compared between the two different standards. The studied object is a nursing home in Åkersberg which is a district in Enköping. The home is divided into 57 apartments and spaces like the kitchen, dinery, lounge, toilets and area for the staff that you find in a nursing home. The total floorarea is 4634 m2 and the building has 3 storeys. The framework consists of wood and concrete. An energy calculation was performed using the building energy simulation program VIP-energy by a consultant. This calculation was used in this report. Due to removal of photovoltaic cells and less effective outer building components, the energy consumption was then increased. In the calculation program Bidcon a quantity calculation was made according to the original building. Due to the changes in VIP-energy with the removal of photovoltaic cells and a less effective outer building component the quantity calculation was modified. The calculations show that the production cost was about 1.6 million SEK higher for the buildingstandard of Miljöbyggnad silver, than for the buildingstandard of Boverket’s regulations. The life cycle cost calculated with economic life span of 30 years for the outer building component shows that it was about 200 000 SEK more expensive when built according to the building standard BBR19, than when built according to Miljöbyggnad silver.
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Ahmad, Ban, e Gustav Vieglins. "A energy and cost comparison between a BBR and a passive apartment building". Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-131976.
Testo completoAbstract (sommario):
Idag ställer samhället och konsumenterna allt större krav på klimatsmarta boenden för att minska energianvändningen. Trots det byggs fortfarande till stor del traditionella hus efter Boverkets byggregler. På uppdrag av WSP studerar denna rapport hur energiåtgången hos ett befintligt flerbostadshus i Stockholm, byggt efter BBR, hade sett ut om det uppförts för att fylla kravspecifikationen för passivhus enligt FEBY12. Samt hur livscykelkostnaderna hade skiljt sig för de två husen. Studien inleddes med en datainsamling av för det befintliga flerbostadshusets areor samt Uvärdena och följs upp med simuleringar av flerbostadshuset i beräkningsprogrammet Energihuskalkyl. Datorberäkningarna jämfördes med manuella beräkningar för att säkerställa värmeförlusttalet samt andelen köpt energi. Varefter flerbostadshuset anpassades med Kingspans detaljbibliotek för att uppfylla FEBY12s passivhuskrav och följdes upp med samma dator- och manuella beräkningar. Där de båda resultaten presenteras och jämförs. I rapportens andra del undersöks och jämförs de två flerbostadshusens livscykelkostnader, sett till investerings-, drifts- och underhållskostnader. Då beställaren sekretessbelagt de verkliga kostnaderna antogs de verkliga kostnaderna för det befintliga huset från Statistiska Centralbyrån. För att beräkna det teoretiska passivhusets investeringskostnader beräknades materialkostnaderna för de båda husen efter de givna ritningarna. Där skillnaden i materialkostnaderna adderades till investeringskostnaden för det passiva flerbostadshuset. Underhållskostnaderna antogs till detsamma för det passiva flerbostadshuset samtidigt som att driftskostnaderna sänktes procentuellt med den minskade mängden köpt energi från energiberäkningarna.
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Clark, Matthew Patterson. "A Novel Aza-Anthrapyrazole BBR 3378 Arrests Th1 Development Preventing Progression of EAE". University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1438091548.
Testo completo
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Carlsson, Linus, e David Liljenberg. "Anpassning av timmerhus enligt nya energikrav i BBR 29 : Glass House Villa 126". Thesis, KTH, Byggteknik och design, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302481.
Testo completoAbstract (sommario):
Den 1 september 2020 trädde den konsoliderade versionen av Boverkets Byggregler BBR 29 i kraft. En stor del av skillnaden från föregående version var det ökade kravet på energihushållning. Det nya kravet som fastställts innebär att U-medelvärdet är sänkt från 0,4 W/m2K till 0,3 W/m2K. Detta är ett mått på hur väl en byggnad är isolerad. Företaget Kontio expanderade till Sverige från Finland för snart fyra år sedan. De säljer framförallt fritidsboende och småhus byggda av egentillverkade timmerstockar med korslimmad arktisk furu i olika dimensioner. Deras hus säljs på den finska marknaden, men i Sverige har endast vissa timmerdimensioner klarat det gamla kravet från BBR 28. Med det nya kravet måste klimatskärmen anpassas till den nya kravbilden. Tak och golv är färdigprojekterade med låga U-värden, därför finns den största möjligheten för anpassning i väggkonstruktionerna. Med hjälp av givna förutsättningar togs ett antal väggkonstruktioner fram för beräkning av U-värdet. Dessa gav upphov till olika typlösningar som varierar med, förutom väggkonstruktionen, fönstertyper och minskade fönsterareor. Framräknat U-värde för väggkonstruktion låg till grund för beräkning av U-medelvärde tillsammans med U-värde för fönster, golv och tak. Ändringar i väggkonstruktioner kan resultera i en förekomst av fuktproblem. Därför testas dessa med hjälp av en Glaser-tabell som undersöker genom stationära beräkningar huruvida det föreligger någon risk i framtagna väggkonstruktioner. Detta projekt analyserar även för- och nackdelar med timmer i furu och dess värmelagrande funktion som beror på en hög värmekapacitet. Med utgångspunkt i litteraturstudien analyseras och utreds var i konstruktionen man med störst fördel placerar den massiva timmerstrukturen i förhållande till värmeisolering. Alla väggkonstruktioner behövde göras om utom 275 där endast fönstertyp ändrades till de med lägre U-värde. Vid anpassning av väggkonstruktioner med timmerdimension 135 och 205 krävdes mer omfattande åtgärder. Genom att isolera väggarna, ändra fönstertyper och minska fönsterareor kunde kravet på U-medelvärde nås på olika sätt. Ingen av dessa vägguppbyggnader uppvisade tecken på fukttekniska problem.On September 1, 2020, the consolidated version of the National Board of Housing, Building and Planning's Building Rules BBR 29 took effect. A large part of the difference from the previous version was the increased demand for energy management. The new requirement that has been established means that the mean U-value has been reduced from 0.4 W/m2K to 0.3 W/m2K. This is a measurement of how well a building is insulated. Almost four years ago, the company Kontio expanded to Sweden from Finland. They mainly sell holiday homes and living houses built from self-made logs with cross-laminated arctic pine in various dimensions. Their houses are sold on the Finnish market, but in Sweden only certain timber dimensions have met the old requirement from BBR 28. With the new BBR 29, the building shell must be adapted to the new requirement. Ceilings and floors are pre-designed with low U-values and for this reason further improvements are best made in the wall construction. Using the given conditions, a number of wall constructions were developed for calculating the U-value. These gave rise to different type solutions that vary with, in addition to the wall construction, window types and reduced window areas. Calculated U-value for wall construction was the basis for calculating the mean U-value together with the U-value for windows, floors and ceilings. Changes in wall constructions can result in the occurrence of moisture problems, therefore these walls are tested using a Glaser-table which examines, by stationary calculations, whether there is any risk in the adapted constructions. This project also analyzes the advantages and disadvantages of pine timber and its heat storage function due to its high heat capacity. Based on the literature study, it is analyzed and investigated where in the construction the massive timber structure is placed with the greatest advantage in relation to the thermal insulation. All wall constructions needed to be adapted except 275 where only the window type was changed to those with a lower U-value. When adapting wall constructions with timber dimensions 135 and 205, more extensive measures were required. By insulating the walls, changing window types and reducing window areas, the requirement for the mean U-value could be achieved in various ways. None of these wall constructions showed signs of moisture technical problems.
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Jablonska, Sylvia, e Alaa Mohammed. "Budget- och budgetlös styrning i svenska småföretag". Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-28370.
Testo completo
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Colella, Gennaro Giovanni Domenico. "Molecular analysis of DNA damage induced by a novel trinuclear platinum complex (BBR 3464)". Thesis, Open University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343821.
Testo completo
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Strömberg, Daniel, e Simon Hjelm. "Energiförbättring av nybyggnation : Vad innebär de nya Boverkets byggregler (BBR), för framtidens VVS-projektering?" Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-44582.
Testo completoAbstract (sommario):
The first of July 2017, Boverket implemented new rules on how to calculate a buildings energy use. This was the first of two steps where Boverket implemented use with a factor depending on the type of energy used in the building and also a factor depending on the location of the building in Sweden. This removed the four zones that were previously used and gave all of Sweden the same energy requirement of 85 kWh/m2 Atemp, year. In the second step, a referral was sent with suggestions of the new stricter requirement to 2020. In the second change, the factors for energy use with electricity and district heating changed from 1,6 to 1,85 for electricity and respectively 1,0 to 0,95 for district heating. In the thesis, an apartment building in Västerås has been investigated. The primary energy has been evaluated in three different cases with different heating. District heating and geothermal heat pump has been calculated separately but also in combination with each other and with solutions as, from supply air ventilation with heat recovery (FTX) and solar panels. The purpose of the thesis is to see how future energy solutions are affected by the changes in Boverket and how to achieve the upcoming energy use regulations that are put on an apartment block. With calculations of the numbers that were implemented in 2017, the primary energy was calculated to 89,3 kWh/m2 Atemp, year for heat pump with district heating, 95,5 kWh/m2 Atemp, year for district heating and 119,4 kWh/ m2Atemp, year for the geothermal heat pump. When the primary energy was calculated with the suggested changes from the referral the value with geothermal heat pump with district heating changed to 92,9 kWh/m2 Atemp, year, with only district heating this changed to 93,6 kWh/m2 Atemp, year and with only a geothermal heat pump it changed to 138 kWh/m2 Atemp, year. This meant that none of the cases met the current 2017 requirement of 85 kWh/m2 Atemp, year and none met the requirement of the 2020 referrals of 78 kWh/m2 Atemp, year. The change that gave the most significant change in primary energy was to install FTX in the building. Results with FTX presents the primary energy for heat pump with district heating decreased from 92,9 kWh/m2 Atemp, year to 75,8 kWh/m2 Atemp, year, and in combination with district heating from 93,6 kWh/m2 Atemp, year to 76,3 kWh/m2 Atemp, year and heat pump decreased from 138 kWh/m2 Atemp, year to 106,5 kWh/m2 Atemp, year. This change made all the cases except the geothermal heat pump reach the 2020 requirement of 78 kWh/m2 Atemp, year. The conclusion of this work is that the possibilities to achieve the requirements are good and that the most challenging case to reach them is with the geothermal heat pump. But it comes with a higher price where investments are getting bigger and higher demands will be made on distributors and the execution. Therefore, it is crucial to find the best solution from both an energy perspective but also an economic perspective.
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Tengdelius, Fredric. "Converting an attic into smaller homes". Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119965.
Testo completoAbstract (sommario):
I detta arbete tar jag upp en del av den lagändring i BBR som började gälla den 1 juli 2014. Den handlar om att lägenheter på max 35 m2 som inreds på en vind inte behöver anpassas för tillgänglighet. Mitt syfte är att bredda kunskapen om denna lagändring och belysa vad man bör tänka på vid vindsinredningar enligt denna. I arbetet studerar jag vilka faktorer som spelar in och i vilken utsträckning lagändringen kan innebära en lättnad för byggbranchen. Vidare tar jag även upp frågan vad personer som är aktiva i byggbranchen tycker om lagändringen och om den kan komma till någon nytta. Till min hjälp har jag Riksbyggen i Linköping där jag gick igenom deras arkiv för att se om det finns några objekt där lagändringen kan appliceras. Min kontaktperson på Riksbyggen, Kristina Cleber, hjälpte mig även att komma i kontakt med aktiva i byggbranchen. Min studie visar att även om de flesta i byggbranchen tycker att lagändringen är bra så är de tveksamma till att den kommer uppfylla sitt syfte, vilket är att avhjälpa bostadsbristen hos unga och studenter. Vidare visar jag att det är en krånglig process att inreda vindsutrymmen då allt material och manskap måste transporteras upp till vinden på något sätt och att installationer kan ställa till problem. De jag intervjuade tycker att man bör utföra en inredning i samband med något annat större projekt för att sprida ut kostnaderna.
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Dale, Paul David. "Time heals all wounds? : mathematical models of epithelial and dermal wound healing". Thesis, University of Oxford, 1995. http://ora.ox.ac.uk/objects/uuid:aaa4717f-a115-4a34-bb03-d64ce81841d9.
Testo completoAbstract (sommario):
The mechanisms responsible for the healing of corneal surface wounds are the subject of biological controversy. In particular, the role and source of the regulatory chemical epidermal growth factor (EGF) is an area of intense debate. In the first part of this thesis, we propose a reaction-diffusion model which focuses on the stimulus for increased mitotic and migratory activity due to secretion of EGF. A detailed numerical study of various possible models, with parameter values based on biological data, reveals that, for realistic healing times, EGF must be released by the underlying layers of the cornea, in addition to the tear film source. The model exhibits travelling wave solutions and further analysis elucidates the interaction and role of the parameters in determining the speed of healing. Furthermore, we consider the effect of topical application of EGF and investigate the effect of curvature of the eye. We show that our model is consistent with many of the key features of corneal wound healing. Adult dermal wounds, in contrast to foetal wounds, heal with the formation of scar tissue. A crucial factor in determining the nature of the healed tissue is the ratio of collagen 1 to collagen 3, which indicates the fibril diameter. We develop a reaction-diffusion model which focuses on the stimulus for collagen synthesis due to the secretion of the different isoforms of the regulatory chemical transforming growth factor β (TGFβ). Numerical simulations of the model without diffusion lead to a value of this ratio consistent with that of healthy tissue for the foetus but corresponding to scarring in the adult. The model equations evolve to waves moving into the wound, but addition of TGFβ only has a transient effect on the final collagen levels. We investigate this effect by developing a caricature model. The model indicates that the main source of the fibroblasts is the underlying subcutaneous tissue and we determine key parameters which explain the difference between adult and foetal wound healing. Furthermore we make clinically testable predictions on the effects that topical application of various chemicals will have on scar formation.
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Duering, Andreas. "From individuals to settlement patterns". Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:f412230f-bbe3-4d07-99b5-ad553bd8b245.
Testo completoAbstract (sommario):
This thesis describes and contextualises the Population & Cemetery Simulator (PCS), which represents agent-based demographic modelling software that can be used to model living populations based on archaeological and historical data as well as their cemeteries. The data used by the PCS are demographic in nature, e.g. age and sex data generated by osteoarchaeologists from excavated cemeteries or historical demographic data. This thesis seeks to provide a methodological foundation for modelling the demographics of archaeological populations. It focusses on case studies using data from early medieval Anglo-Saxon (South England) and Alamannic (South Germany) cemeteries, although excursions into neighbouring periods and regions are included as validation studies. The case studies show how the PCS can be used in archaeological research and the software is presented as a solution to various problems caused by the difference between the living population and the 'dead' cemetery data in archaeology.
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Matheson, Julia Anne Helen. "E-cadherin loss of function in the murine intestine". Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:c5a61fcd-e0a2-4af7-bb53-c78c3a47874f.
Testo completoAbstract (sommario):
E-cadherin (Cdh1), is a major component of epithelial adherens junctions, binds the Wnt pathway effector β-catenin and is lost at the invasive edge of colon cancers. Crypt stem cells give rise to 4 cell lineages that, with the exception of Paneth cells, travel along the crypt-villus axis over 3 days and are shed by anoikis. Gain of function of the Wnt pathway by a mutation in Adenomatous Polyposis Coli (Apc) disrupts enterocyte turnover to result in adenoma formation. Homozygote null Cdh1 is embryonic lethal, and heterozygote Cdh1 can promote Apc1638N induced adenoma formation, but we lack models that assess additional functions of Cdh1 in the adenoma to carcinoma transition. The aim of this thesis was to evaluate the effect of Cdh1 loss of function in the murine intestine, including in the setting of Wnt pathway activation. To do this, germline and intestinal specific conditional Cdh1 loss of function models were generated. Conditional homozygous deletion of Cdh1 resulted in embryonic lethality using Villin-Cre. In adults, homozygous Cdh1 loss using the tamoxifen inducible Villin-CreERT2 led to intestinal inflammation, bacteraemia and disrupted crypt-villus architecture. Combined conditional homozygous deletion of Cdh1 and Apc resulted in Wnt pathway upregulation assessed by β-catenin immunolabelling. Strain dependent effects of Cdh1 heterozygosity were apparent on the Apc heterozygote background: ApcMin/+ Cdh1+/- (C57BL/6J) had no effect on survival or adenoma phenotype compared to littermate ApcMin/+; Cdh1+/fl increased adenoma burden in Apc+/fl Vil-Cre animals (B6D2/C57BL/6J). Low frequency recombination of Apcfl/fl using Lgr5-EGFP-IRES-CreERT2 bypasses the loss of heterozygosity event relied on in heterozygous Apc tumour models achieving a large adenoma burden within 4 weeks. Cdh1 loss did not alter survival or adenoma phenotype in this model, including the development of large caecal tumours. Immunolabelling of tumours from Apcfl/fl Cdh1fl/fl animals showed persistent E-cadherin protein expression, suggesting incomplete recombination or that double homozygote enterocytes failed to survive. In vitro adenoma culture was used to test whether E-cadherin loss was incompatible with enterocyte survival in the setting of Wnt activation. Apcfl/fl Cdh1+/+ and Apcfl/fl Cdh1fl/fl adenoma were cultured in matrigel and treated with an adenovirus expressing Cre recombinase under a CMV promoter (Ad-Cre). Ad-Cre had no effect on Apcfl/fl Cdh1+/+ adenoma growth. Ad-Cre treated Apcfl/fl Cdh1fl/fl adenoma organoids showed cells where E‑cadherin loss resulted in Wnt pathway upregulation as assessed by nuclear β-catenin and Axin2 expression, and epithelial mesenchymal transition shown by upregulation of fibronectin, twist and vimentin. This work supports a role for E-cadherin in modulation of the Wnt pathway. Further investigation is required to define the cell adhesion versus Wnt regulatory functions of E-cadherin.
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Muehlemann, Anton. "Variational models in martensitic phase transformations with applications to steels". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:bb7f4ff4-0911-4dad-bb23-ada904839d73.
Testo completoAbstract (sommario):
This thesis concerns the mathematical modelling of phase transformations with a special emphasis on martensitic phase transformations and their application to the modelling of steels. In Chapter 1, we develop a framework that determines the optimal transformation strain between any two Bravais lattices and use it to give a rigorous proof of a conjecture by E.C. Bain in 1924 on the optimality of the so-called Bain strain. In Chapter 2, we review the Ball-James model and related concepts. We present some simplification of existing results. In Chapter 3, we pose a conjecture for the explicit form of the quasiconvex hull of the three tetragonal wells, known as the three-well problem. We present a new approach to finding inner and outer bounds. In Chapter 4, we focus on highly compatible, so called self-accommodating, martensitic structures and present new results on their fine properties such as estimates on their minimum complexity and bounds on the relative proportion of each martensitic variant in them. In Chapter 5, we investigate the contrary situation when self-accommodating microstructures do not exist. We determine, whether in this situation, it is still energetically favourable to nucleate martensite within austenite. By constructing different types of inclusions, we find that the optimal shape of an inclusion is flat and thin which is in agreement with experimental observation. In Chapter 6, we introduce a mechanism that identifies transformation strains with orientation relationships. This mechanism allows us to develop a simpler, strain-based approach to phase transformation models in steels. One novelty of this approach is the derivation of an explicit dependence of the orientation relationships on the ratio of tetragonality of the product phase. In Chapter 7, we establish a correspondence between common phenomenological models for steels and the Ball-James model. This correspondence is then used to develop a new theory for the (5 5 7) lath transformation in low-carbon steels. Compared to existing theories, this new approach requires a significantly smaller number of input parameters. Furthermore, it predicts a microstructure morphology which differs from what is conventionally believed.
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Ploutarchou, Panayiota. "Effect of oocyte glycoproteins on ovarian follicle development and function". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:ab1bad0c-bb83-48ec-82cc-be122c3dc02e.
Testo completoAbstract (sommario):
The precise mechanisms that regulate the ovulation rate of species are not entirely understood. The C1galt1 Mutant mouse, in which oocytes lack core 1-derived O-glycans, is characterised by (i) increased fertility, evident from ~40-50% larger litters as a result of increased number of growing follicles and (ii) modified cumulus expansion. Work carried out in this thesis investigated both of these phenotypes and led to the understanding of possible mechanisms involved in increased fertility. Through detailed analysis of the cumulus complex both prior- and post-ovulation in Control mice, novel characteristics regarding the physiology of cumulus expansion have been found. In addition, the analysis of C1galt1 Mutants has revealed that a functional cumulus-oocyte-complex requires the essential components to be present above a minimum threshold level, and thus some variation in ECM composition does not adversely affect oocyte development, ovulation or fertilisation. These data have important implications for IVF and the use of cumulus expansion as a criterion for oocyte assessment. C1galt1 Mutants have (i) altered follicle growth characteristics, (ii) reduction in apoptosis levels and (iii) reduction in AMH levels, all of which could be directly or indirectly contributing to the increased fertility phenotype. These data reveal new and important roles for the oocyte in follicle development and female fertility, providing perspectives for future work in female reproduction.
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Francis-Dehqani, Gulnar Eleanor. "Religious feminism in an age of empire : CMS women missionaries in Iran, 1869-1934". Thesis, University of Bristol, 1999. http://hdl.handle.net/1983/5d1e6911-e7e7-4393-bb43-f287f2f61ac9.
Testo completo
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Ward, Harriet. "The charitable relationship : parents, children and the Waifs and Strays Society". Thesis, University of Bristol, 1990. http://hdl.handle.net/1983/31d48600-bb93-43d1-8493-b8e56f00a0ea.
Testo completo
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Finkel, Kelsey Jo. "Exploring the writer's toolbox : a study of how writers and their use of writing implements and surfaces relate to their ways of thinking for writing". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:daaae0e7-10f0-4c9f-bbe3-8157c2fa47df.
Testo completoAbstract (sommario):
The state of writing abilities throughout the United States presents an urgent issue. Low student achievement in English Language Arts (ELA) exams and standardized English assessments persist (National Center for Education Statistics, 2012), while businesses spend billions of dollars on remedial writing instruction (Dillon, 2008). Technology is increasingly cited as a potential solution to these issues. Evidence for this is limited, as is existing research into the basis of the issues that technology might address. On account of that context, this thesis turns to a basic distinction between digital and non-digital writing: the writing surface and implement, or pen and paper - screen and keyboard. Conceptualizing such artefacts through a view of writing as a way of thinking raises the following question, which is this study's guiding inquiry. Might we use digital implements and surfaces to support the ways of thinking involved in composing written works of semantic cohesion? Building on research into writing as thinking, the study presented in this document analyses how uses of writing surfaces and implements relate to ways of thinking while writing, and which contextual factors influence those relationships. Drawing on a neuro-anthropological approach, the study focuses on the writer's mind as the driver and source of the lived experience of writing. Expert writers, therefore, are considered to be those who exhibit the ways of thinking while writing to which other writers aspire. To examine a range of uses of writing surfaces and implements with reference to expert writers' ways of thinking, the study was conducted in two parts. Part 1involved a content analysis of published interviews with professional writers. This generated a framework through which to conduct in-depth qualitative research with college student writers - part 2. This thesis is as much about thinking while writing as it is about the different tools available for writing. As such, the study refutes the hyperbolic and deterministic claims about technology and writing, and finds that technology is not leading to new ways of thinking while writing. Instead, surfaces and implements available allow writers to change how they practise their ways of thinking while writing. By considering this distinction and developing understandings of the dynamics involved and their implications, writers may begin to realize the potential of technology for writing. Ultimately, this thesis contributes to existing theories on writing through an informed discussion of how to think about implements and surfaces in ways that support writerly thinking, and by offering fresh ways to think about the lived practice of writing.
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Kulakov, Mikhail. "The infinite diversity of persons : individual personality in the ascetical theology of St Feofan the Recluse (1815-1894)". Thesis, University of Oxford, 2000. https://ora.ox.ac.uk/objects/uuid:a184a287-dd28-44c1-bb33-5ab2c0782d70.
Testo completoAbstract (sommario):
The teachings of St. Feofan (1815-1894), together with his celebrated Russian translation of the Philokalia, played a major role in the spiritual revival of nineteenth century Russia, earning him the reputation of one of the greatest Russian theoreticians of Orthodox mysticism. Yet Feofan also provoked fierce criticism of such eminent Russian thinkers as Nicolas Berdyaev. This study focuses on one of the most significant elements of Feofan's legacy: the notion of legitimacy of spiritual diversity. This idea permeates Feofan's discussions of the striking dissimilarities demonstrated by persons engaged in ascetic and spiritual pursuits. It is highlighted by the fact that Feofan derives his positive attitude to diversity from within the tradition generally perceived as intolerant of dissent and non-conformity. Based within a wider context of Orthodox mystical tradition, this study examines Feofan's major writings, his work with the texts of the Philokalia, and his public and private correspondence. Attention is given to such pivotal concepts as his notions of the spirit and the heart; intimate communion with God; and the cardinal importance of spiritual self-consciousness. The study reveals Feofan's indebtedness to Byzantine ascetic spirituality, as well as his unusual openness to Western thought - reflected in his innovative synthesis of patristic asceticism and German romantic psychology. This study also addresses the ambivalence of Feofan's inner conflicts: namely, between his passionate belief in spiritual self-determination and his authoritarian teaching on 'silent submissiveness'; and between his defence of the legitimacy of spiritual diversity within the realm of ascetic experience and his unwillingness to extend that same principle beyond the limits of his own tradition. The thesis is not only the first critical account in English of Feofan's spiritual teaching, but is also an ecumenical exercise in which attitudes toward religious diversity within the Russian monastic tradition are examined by a Russian evangelical.
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Li, Dong. "Robust optimisation with applications in supply chain management". Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:b6150a21-5eb5-4838-bb63-8b13de1ac7a9.
Testo completoAbstract (sommario):
We consider a production planning problem in supply chain management, namely the lot sizing problem under uncertainty. Lot sizing problems contain a fairly high degree of uncertainty in real life. Thus pre-decided optimal production plans are no longer of practical use. Current methods to address the uncertainty in the lot sizing problem either make strong assumptions or increase the complexity of the deterministic model significantly. In this study, we propose lot sizing models that use robust optimization to deal with uncertainty in demand and production costs. These models provide a good trade-off between the robustness of the solution, i.e., to what extent the solution is feasible, and the quality of the objective function value. Four robust methodologies are used, namely, the minimax regret criterion, the uncertainty budget, the uncertainty range, and the bw-robustness criterion. With the minimax regret criterion, the robust lot sizing model aims to achieve a production plan that minimizes the maximum surplus between the total cost of the production plan and that of the optimal production plan after revealing the uncertain data. With the uncertainty budget and the uncertainty range, the robust lot sizing model minimizes the maximum total cost that could occur due to the uncertain data. However, the size of the total uncertainty is bounded by the uncertainty budget and the scope of the allocation of the uncertainty data is bounded by the uncertainty range. The bw-robust lot sizing model identifies a production plan that guarantees an objective function value of at most w in all data circumstances and maximizes the probability that the objective function is below b. While the main priority of most classic robust optimization approaches is to deal with feasibility, the quality of the objective function value is equally important to the decision maker in the process of production planning. In this thesis, we focus more on the quality of the objective function and, besides being robust, we model explicitly how the uncertain parameters affect the total production cost in the lot sizing problem. As far as the author is aware, the minimax regret lot sizing study is the first to consider uncertainty in both the coeficients of the objective function and a parameter that defines the feasible region, and the bw-robust lot sizing study is the first to deal with a parameter that defines the feasible region. With the popular idea of uncertainty budget, we redefine the worst case caused by data uncertainty as when it harms the objective function value the most, and extend this idea by further proposing the uncertainty range parameter which helps to provide a better trade-off between robustness and the quality of the objective function value. Efficient polynomial time algorithms are proposed for the minimax regret uncapacitated lot sizing model, the robust lot sizing model with uncertainty budget, and the robust lot sizing model with uncertainty range. For the bw-robust lot sizing model with demand uncertainty, we propose Mixed Integer Nonlinear Programming formulations, which are reformulated as Mixed Integer Linear Programming formulations and solved with a commercial package. Numerical results are provided with various settings of parameters to show the effectiveness of the solutions of the proposed robust lot sizing models, in terms of feasibility and quality of the objective function.
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Thunmarker, Camilla, e Louise Saaranen. "Energieffektiv förskola : Utformning och gestaltning av en passivhusförskola". Thesis, KTH, Byggteknik och design, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-101716.
Testo completoAbstract (sommario):
En expandering av storstäder har bidragit till att nya behov måste uppfyllas. Däribland behovet av nya förskolor. Idag och i framtiden kommer det ställas höga krav på att nya byggnader ska bli mer energieffektiva och det är viktigt att kommuner ligger i framkant i denna utveckling då de ska vara ett föredöme i samhället. Valet föll därför på att kombinera dessa behov och krav genom att gestalta en energieffektiv förskola i Haninge kommun som är i ett expansivt skede. Genom inventering av befintlig information kring ämnena förskola och energieffektivt byggande, samt studiebesök och fallstudier valdes att förskolan skulle gestaltas enligt passivhusteknik. Informationen behandlar bland annat krav från BBR, FEBY och Lpfö98. Det var genom dessa metoder som ett lokalprogram innehållandes en sambandsanalys kunde tas fram för kommandeförskola. Förskolan som passivhus innebär förändrade förutsättningar för gestaltningen då det är viktigt att i ett tidigt skede planera planlösningen så att den medverkar till en energibesparing. Utifrån lokalprogrammet kunde förskolan Lövet som enligt enkla beräkningar uppfyller kraven för passivhus. Förslaget stämmer bra överrens med det lokalprogram som det grundades på tack vare det djupgående förarbetet. Slutsatsen blir att ett väl bearbetat lokalprogram är en bra förutsättning för att gestalta och konstruera ett förslag som är realistiskt. I detta projekt har det visat sig att det är möjligt att bygga en förskola i passivhusteknik trots ändrade förutsättningar angående teknik samt utformning. Ett passivhus är dessutom ett bra pedagogiskt läromedel att lära barn hur energi kan besparas.An expansion of big cities has contributed to new requirements that must be fulfilled. The requirements include the need for new preschools. Today and tomorrow there will be demands for new buildings to be energy efficient and it is important that municipalities are at the forefront of this development as they will set an example in the community. The choice was made to combine these needs and requirements by designing an energy efficient preschool in the municipality of Haninge which is a municipality in an expansive phase. The choice to make the preschool according to passive house technology was made through inventory of existing information about the areas of preschool and energy- efficient construction, as well as visits and case studies. The information treats, among other things, requirement from BBR, FEBY and Lpfö98. It was also through these methods that a local program with an analysis of the connections between rooms was generated for the preschool. Preschool as a passive house results in changing conditions for the conformation and that is why it is important that in an early stage plan the layout so that it contributes to energy savings. Through calculations made from the construction of the preschool, which is based on the local program containing an analysis of the connections between rooms, meet the requirements for passive houses. The proposal agrees with the local program that it was based on, thanks to the deep preliminary work. The conclusion is that a well-developed local program is a good prerequisite in order to design and construct a proposal that is realistic. This project has shown that it is possible to build a preschool in passive house technology despite changed conditions regarding technology and design. Passive house is also a good educational material to teach children how energy can be saved.
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Santi, Luca. "Intron mediated regulation of BKn3, a plant homeobox gene, as supported by BBR (GAGA) binding factor". [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965410145.
Testo completo
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Breding, Sara, e Edona Dinaku. "Miljöklassning av en idrottshall i Hjorthagen : En granskning av miljökraven för Miljöbyggnad, BBR 22 och Passivhus". Thesis, KTH, Byggteknik och design, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213456.
Testo completoAbstract (sommario):
Företag inom byggsektorn strävar efter att minimera byggnaders energianvändning och att minska miljöpåverkan genom hela byggprocessen. Byggherrar ställer ofta krav på att ett byggprojekt ska uppnå vissa miljökrav eller att byggnaden ska miljöcertifieras. När ett byggprojekt ska uppnå flera miljöklassningar tar projekteringen av miljökraven ofta längre tid. Syftet med studien är att undersöka vilka miljökrav som gäller för projektet Hjorthagshallen och analysera i vilken utsträckning det är möjligt att uppnå kraven. Projektet Hjorthagshallen innefattar nyproduktion av en idrottshall i Norra Djurgårdsstaden. Byggnaden ska: • Certifieras enligt Miljöbyggnad GULD • Uppnå kraven för BBR 22 • Uppnå kraven för Passivhus En litteraturstudie genomfördes för att undersöka vilka miljökrav som gäller för projektet och dessa sammanställdes sedan i en översiktlig tabell. Miljökraven har analyserats och utvärderats med beräkningsverktyg, simuleringsprogram, referensprojekt och med projektspecifika handlingar. De indikatorer som ansågs vara svårast att bedöma i förväg i denna studie var energianvändningen, luftläckningen genom klimatskalet och det termiska klimatet. Studien visar att miljökraven för projektet Hjorthagshallen är möjliga att uppnå. Många krav och indikatorer går att säkerställa under projekteringen medan vissa indikatorer är svårare att säkerställa innan byggnaden är färdigställd.Construction companies aim to reduce the energy use of buildings and to minimize the environmental impact throughout the entire construction process. Constructors often require the project to meet certain environmental requirements and to certify the building. When a construction project aims to achieve several classifications the projection of the requirements often takes more time. This study aims to identify the environmental requirements that apply to the project Hjorthagshallen and to analyze if it is possible to achieve these requirements. Hjorthagshallen will be a sports center in Norra Djurgårdsstaden. The building will: • Be certified according to Miljöbyggnad GULD • Achieve the requirements for BBR 22 • Achieve the requirements for Passivhus. The environmental requirements for Hjorthagshallen have been collected through a literature study and presented in an overview table. The environmental requirements have been analyzed with calculation tools, simulation programs, a reference project and project documents. The indicators considered to be the most difficult to estimate in advance in this study are the energy use, air leakage and the thermal climate. The conclusion is that the environmental requirements for Hjorthagshallen are likely to be met. Many requirements and indicators can be ensured during the projection while some indicators are more difficult to ensure before the building is completed. Keywords:
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Suska, Olga. "Investigating the role and regulation of mRNA capping in pluripotency and differentiation". Thesis, University of Dundee, 2017. https://discovery.dundee.ac.uk/en/studentTheses/7dc7a533-845b-4c49-bb93-c8a6cfae8508.
Testo completoAbstract (sommario):
The mRNA cap added to the 5’ end of nascent transcripts is required for the efficient gene expression in eukaryotes. In vertebrates, the guanosine cap is methylated at N7 position by RNMT, which is in complex with its activating subunit RAM. Additionally, the first and second transcribed nucleotides can be methylated at ribose O2 position by CMTR1 and CMTR2 respectively. The mRNA cap protects transcripts from degradation and recruits cap-binding factors to promote pre-mRNA processing, nuclear export and translation initiation. In mouse embryonic stem cells (mESCs), high levels of RAM maintain expression of pluripotency factors. Differentiation of mESCs to neural progenitors is accompanied by a suppression of RAM, resulting in downregulation of pluripotency factors and efficient formation of neural cells. Here, I demonstrated that the suppression of RAM during neural differentiation is promoted via ubiquitination and proteasomal degradation. Concurrently, neural differentiation is associated with an increase in CMTR1 expression, creating a developmental cap methyltransferase switch. Moreover, differentiation into endodermal and mesodermal lineages exhibited distinct changes in the mRNA capping enzymes expression. In mESCs, RAM promotes expression of translation-associated proteins and promotes global loading of mRNA on ribosomes. RAM contributes to the ESC-specific gene expression program, by maintaining optimal expression of pluripotency-associated transcripts and inhibiting expression of neural genes. Chromatin immunoprecipitation revealed that RAM, RNMT and CMTR1 promote binding of RNA polymerase II at gene loci. In RAM-repressed cells, RNA polymerase II binding was reduced at pluripotency-associated genes, but relatively increased at neural genes. Moreover, knock-down of RNMT or CMTR1 induced increased or decreased accumulation of RNA polymerase II at promoter proximal regions respectively. In naïve T cells, Rnmt or Cmtr1 conditional knock-outs caused downregulation of translation-related transcripts and upregulation of cell cycle transcripts. Furthermore, many transcripts were specifically dependent on RNMT or CMTR1 for expression, demonstrating distinct roles of these cap methyltransferases. Thus, the mRNA cap methylation emerges as an important regulator of pluripotency and differentiation, modulating gene expression at transcriptional and post-transcriptional levels.
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Devenish, Annie Victoria. "Being, belonging and becoming : a study of gender in the making of post-colonial citizenship in India 1946-1961". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:8fbbf3b1-bb13-47a4-aee2-dd7b5dfb7804.
Testo completoAbstract (sommario):
Concentrating on the time frame between the establishment of India's Constituent Assembly in 1946, and the passing of the Dowry Prevention Act in 1961, this thesis attempts to write an alternative history of India's transition to Independence, by applying the tools of feminist historiography to this crucial period of citizenship making, as a way of offering new perspectives on the nature, meaning and boundaries of citizenship in post-colonial India. It focuses on a cohort of nationalists and feminists who were leading members of two prominent women's organisations, the All India Women's Conference (AIWC) and the National Federation of Indian Women (NFIW), documenting and analysing the voices and positions of this cohort in some of the key debates around nation building in Nehruvian India. It also traces and analyses the range of activities and struggles engaged in by these two women's organisations - as articulations and expressions of citizenship in practice. The intention in so doing is to address three key questions or areas of exploration. Firstly to analyse and document how gender relations and contemporary understandings of gender difference, both acted upon and were shaped by the emerging identity of the Indian as postcolonial citizen, and how this dynamic interaction was situated within a broader matrix of struggles and competing identities including those of minority rights. Secondly to analyse how the framework of postcolonial Indian citizenship has both created new possibilities for empowerment, but simultaneously set new limitations on how the Indian women's movement was able to imagine itself as a political constituency and the feminist agenda it was able to articulate and pursue. Thirdly to explore how applying a feminist historiography to the story of the construction of postcolonial Indian citizenship calls for the ability to think about the meaning and possibilities of citizenship in new and different ways, to challenge the very conceptual frameworks that define the term.
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Barush, Kathryn R. ""Every age is a Canterbury pilgrimage" : art and the sacred journey in Britain, c. 1790-1850". Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:63e1545c-1362-4bc3-bbc3-b950eecf7c70.
Testo completoAbstract (sommario):
This thesis examines the intersections of the concept of pilgrimage and the visual imagination in Britain from the years 1790 to 1850. Historically, distinctions between understandings of pilgrimage as motif, metaphor, artistic process, and actual journey have been blurred to varying degrees, resulting in the creation of images that were at once narratives, memorials, and stimuli for contemplative journeys from pictorial space to imagination. In the first half of the nineteenth century, religious architecture, sacred landscapes, and the emblematic figure of the pilgrim with coat, hat, and scrip functioned as temporal reminders of a promised land to come, as mediated through artistic practice. Through a close analysis of a range of interrelated visual sources, I contend that pilgrimage, both in practice and as a form of mental contemplation, helped to shape the religious, literary, and artistic imagination of the period and beyond. This study draws out the various levels at which pilgrimage engaged the visual imagination. In doing so it offers a detailed perspective on the conjunction of content, form, meaning, and process for artists and theorists, as notions of the transfer of ‘spirit’ from sacred space to represented space re-emerged as a key aspect of the theological and artistic discourse of the period. Chapter 1 outlines the antiquarian dissemination of medieval pilgrimage texts and images. I suggest that an awareness of pilgrimage as embodying the real and imagined emerged with the recovery of allegorical texts, histories of actual pilgrimages, and an interest in pilgrimage souvenirs. The discussion moves on to intersections between pilgrimage and religious art in Chapters 2 - 4, including the idea of painting as pilgrimage, as demonstrated through specific case studies, and the refashioning of relics and religious ruins as contemporary sites of pilgrimage (Chapter 5).
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May, Peter F. J. "Tethered fluorophore motion studies of DNA segregation machinery". Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:1d909673-82a4-4b03-bb33-46e2a1526f63.
Testo completoAbstract (sommario):
Tethered fluorophore motion (TFM) is a single-molecule fluorescence technique, used to monitor an effective length along a biopolymer, such as DNA. In this work, I start by characterising TFM, focussing on the theoretical basis and potential applications, and then use TFM to study the bacterial site specific recombination system, XerCD-dif. I present a description of the sources of noise in TFM and derive an analytical expression for the resolution, which is compared to simulations and experiments. The work demonstrates that length changes as low as 100 bp of double-stranded DNA are distinguishable using TFM. The optimum pixel size for TFM is derived and validated experimentally. XerCD-dif recombination is responsible for chromosome decatenation in most bacteria with circular chromosomes. It is activated by the DNA translocase FtsK. I describe the application of TFM, in combination with Förster resonance energy transfer (FRET) and protein induced fluorescence enhancement, to observe the formation and activation of XerCD-dif synaptic complexes. The work followed the reaction, as Holliday junctions formed by XerD-mediated strand exchange isomerised and were resolved to product by XerC, and measured the lifetimes of all the intermediates observed. To analyse the role of FtsK in the activation of recombination, and to monitor its assembly, translocation and behaviour when encountering XerCD-dif, TFM was extended with the use of two spectrally distinct fluorophores, allowing simultaneous monitoring of two effective lengths along the same DNA. FtsK was observed to assemble on DNA, stepwise, into a single hexamer, and begin translocation rapidly (~0.25 s). Single hexamers approached XerCD-dif, and resided for 0.5s to 1s before dissociating, irrespective of whether XerCD-dif was synapsed or recombination was activated. The final section of this thesis details the design, construction and evaluation of a three colour microscope. Alternating laser excitation was implemented in the green, red and near-infrared spectral channels with three laser sources, and an inexpensive automatic focus system was implemented using the back reflection of the excitation lasers and a complementary metal oxide semiconductor camera.
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Favara, David M. "The biology of ELTD1/ADGRL4 : a novel regulator of tumour angiogenesis". Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:0d00af0a-bb43-44bc-ba0b-1f8acbe34bc5.
Testo completoAbstract (sommario):
Background: Our laboratory identified ELTD1, an orphan GPCR belonging to the adhesion GPCR family (aGPCR), as a novel regulator of angiogenesis and a potential anti-cancer therapeutic target. ELTD1 is normally expressed in both endothelial cells and vascular smooth muscle cells and expression is significantly increased in the tumour vasculature. The aim of this project was to analyse ELTD1's function in endothelial cells and its role in breast cancer. Method: 62 sequenced vertebrate genomes were interrogated for ELTD1 conservation and domain alterations. A phylogenetic timetree was assembled to establish time estimates for ELTD1's evolution. After ELTD1 silencing, mRNA array profiling was performed on primary human umbilical vein endothelial cells (HUVECs) and validated with qPCR and confocal microscopy. ELTD1's signalling was investigated by applying the aGPCR âStinger/tethered-agonist Hypothesis'. For this, truncated forms of ELTD1 and peptides analogous to the proposed tethered agonist region were designed. FRET-based 2nd messenger (Cisbio IP-1;cAMP) and luciferase-reporter assays (NFAT; NFÎoB; SRE; SRF-RE; CREB) were performed to establish canonical GPCR activation. To further investigate ELTD1's role in endothelial cells, ELTD1 was stably overexpressed in HUVECS. Functional angiogenesis assays and mRNA array profiling were then performed. To investigate ELTD1 in breast cancer, a panel of cell lines representative of all molecular subtypes were screened using qPCR. Furthermore, an exploratory pilot study was performed on matched primary and regional nodal secondary breast cancers (n=43) which were stained for ELTD1 expression. Staining intensity was then scored and compared with relapse free survival and overall survival. Results: ELTD1 arose 435 million years ago (mya) in bony fish and is present in all subsequent vertebrates. ELTD1 has 3 evolutionary variants of which 2 are most common: one variant with 3 EGFs and a variant with 2 EGFs. Additionally, ELTD1 may be ancestral to members of aGPCR family 2. HUVEC mRNA expression profiling after ELTD1 silencing showed upregulation of the mitochondrial citrate transporter SLC25A1, and ACLY which converts cytoplasmic citrate to Acetyl CoA, feeding fatty acid and cholesterol synthesis, and acetylation. A review of lipid droplet (fatty acid and cholesterol) accumulation by confocal microscopy and flow cytometry (FACS) revealed no changes with ELTD1 silencing. Silencing was also shown to affect the Notch pathway (downregulating the Notch ligand JAG1 and target gene HES2; upregulating the Notch ligand DLL4) and inducing KIT, a mediator of haematopoietic (HSC) and endothelial stem cell (ESC) maintenance. Signalling experiments revealed that unlike other aGPCRs, ELTD1 does not couple to any canonical GPCR pathways (Gαi, Gαs, Gαq, Gα12/13). ELTD1 overexpression in HUVECS revealed that ELTD1 induces an endothelial tip cell phenotype by promoting sprouting and capillary formation, inhibiting lumen anastomoses in mature vessels and lowering proliferation rate. There was no effect on wound healing or adhesion to angiogenesis associated matrix components. Gene expression changes following ELTD1 overexpression included upregulation of angiogenesis associated ANTRX1 as well as JAG1 and downregulation of migration associated CCL15 as well as KIT and DLL4. In breast cancer, none of the representative breast cancer cell lines screened expressed ELTD1. ELTD1 breast cancer immunohistochemistry revealed higher levels of vascular ELTD1 staining intensity within the tumour stroma contrasted to normal stroma and expression within tumour epithelial cells. Additionally, ELTD1 expression in tumour vessels was differentially expressed between the primary breast cancer microenvironment and that of the matched regional node. Due to the small size of the pilot study population, survival comparisons between the various subgroups did not yield significant results. Conclusion: ELTD1 is a novel regulator of endothelial metabolism through its suppression of ACLY and the related citrate transporter SLC25A1. ELTD1 also represses KIT, which is known to mediate haematopoietic and endothelial progenitors stem cell maintenance, a possible mechanism through which endothelial cells maintain terminal endothelial differentiation. ELTD1 does not signal like other adhesion GPCRS with CTF and FL forms of ELTD1 not signalling canonically. Additionally, ELTD1 regulates various functions of endothelial cell behaviour and function, inducing an endothelial tip cell phenotype and is highly evolutionarily conserved. Lastly, ELTD1 is differentially expressed in tumour vessels between primary breast cancer and regional nodal metastases and is also expressed in a small subset of breast cancer cells in vivo despite no cancer cell lines expressing ELTD1. The pilot study investigating ELTD1 in the primary breast cancer and regional involved nodes will be followed up with a larger study including the investigation of ELTD1 in distant metastases.
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Maclean, Ewen Hamish. "Modelling and correction of the non-linear transverse dynamics of the LHC from beam-based measurements". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:227fa9d5-bb13-4204-bf6d-6ef0ed885036.
Testo completoAbstract (sommario):
The non-linear beam dynamics of a circular accelerator, such as the Large Hadron Collider, can have a significant impact on its operation. In order to avoid limitations on the performance reach of the accelerator, and ensure machine protection, it is vital that the beam dynamics are well understood and controlled. This thesis presents the results of studies of non-linear beam dynamics undertaken on the Large Hadron Collider at CERN, during the 2010 to 2013 period. It sets out to quantify the understanding of the non-linear beam dynamics through the comparison of beam-based measurements to simulation, and where able and appropriate seeks to explain deviations of measurement from the model, and define corrections for relevant aspects of the dynamics. The analyses presented in this thesis represent considerable advances in the understanding of the LHC beam dynamics which should allow for an improved operation of the machine in the coming years.
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Yoon, Sung-ho. "Applications of the virtual fields method to the mechanical behaviour of rubbers under dynamic loading". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:1a1294b8-8759-41bc-bb53-fc0abbf69f2f.
Testo completoAbstract (sommario):
Experimental techniques for measuring the mechanical response of rubbers under dynamic loading are developed utilising the virtual fields method (VFM), to inversely identify constitutive behaviour from experimental observations. Rubbers and other 'soft' materials are difficult to characterize using traditional dynamic techniques such as the split Hopkinson bar: the low sound speed makes it difficult to achieve static equilibrium and the small supported forces give low signal-to-noise ratios in the experimental data. In this research, the dynamic VFM with the aid of high-speed imaging is applied to dynamic tensile experiments to resolve these difficulties. The VFM is a mathematical technique that makes use of the principle of virtual work. Manipulation of this equation enables us to remove the need for traditional force measurement, instead exploiting acceleration full-field data as a virtual load cell. Thus, the aforementioned difficulties are no longer of concern: the technique requires that the specimen is not in static equilibrium and that inertial forces are significant compared to material forces. Two dynamic tests and dynamic VFMs are developed and applied to tensile drop-weight and gas-gun driven experiments. The first uses small amplitude dynamic deformation superposed on static pre-stretching. Dynamic identifications at a number of pre-strains are collated to identify the complete nonlinear behaviour. The second utilizes a large strain amplitude of dynamic loading: one experiment characterizes the full response. Further applications of the dynamic VFM are explored in order to improve the first method and to extend the identification capability, and experiments performed at non-ambient temperatures allow a preliminary exploration of time-temperature superposition.
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Whitby, Andrew. "Asymptotic analysis of the 1-step recursive Chow test (and variants) in time series model". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:0bb70f36-580d-44f0-bb13-98429f75e31f.
Testo completoAbstract (sommario):
This thesis concerns the asymptotic behaviour of the sequence of 1-step recursive Chow statistics and various tests derived therefrom. The 1-step statistics are produced as diagnostic output in standard econometrics software, and are expected to reflect model misspecification. Such misspecification testing is important in validating the assumptions of a model and so ensuring that subsequent inference is correct. Original contributions to the theory of misspecification testing include (i) a result on the pointwise convergence of the 1-step statistics; (ii) a result on the extreme-value convergence of the maximum of the statistics; and (iii) a result on the weak convergence of an empirical process formed by the statistics. In Chapter 2, we describe the almost sure pointwise convergence of the 1-step statistic for a broad class of time series models and processes, including unit root and explosive processes. We develop an asymptotic equivalence result, and use this to establish the asymptotic distribution of the maximum of a sequence of 1-step statistics with normal errors. This allows joint consideration of the sequence of 1-step tests via its maximum: the sup-Chow test. In Chapter 3, we use simulation to investigate the power properties of this test and compare it with benchmark tests of structural stability. We find that the sup-Chow test may have advantages when the nature of instability is unknown. In Chapter 4, we consider how the test may be adapted to situations in which the errors cannot be assumed normal. We evaluate several promising approaches, but also note a trade-off between robustness and power. In Chapter 5 we analyse an empirical process formed from the 1-step statistics, and prove a weak convergence result. Under the assumption of normal errors, the limiting distribution reduces to that of a Brownian bridge. The asymptotic approximation appears to works well even in small samples.
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Kiwanuka, Robert. "Micro-deformation and texture in engineering materials". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:3c924d01-7501-4d59-bb53-07e6584e50c5.
Testo completoAbstract (sommario):
This DPhil project is set in the context of single crystal elasticity-plasticity finite element modelling. Its core objective was to develop and implement a methodology for predicting the evolution of texture in single and dual-phase material systems. This core objective has been successfully achieved. Modelling texture evolution entails essentially modelling large deformations (as accurately as possible) and taking account of the deformation mechanisms that cause texture to change. The most important deformation mechanisms are slip and twinning. Slip has been modelled in this project and care has been taken to explore conditions where it is the dominant deformation mechanism for the materials studied. Modelling slip demands that one also models dislocations since slip is assumed to occur by the movement of dislocations. In this project a model for geometrically necessary dislocations has been developed and validated against experimental measurements. A texture homogenisation technique which relies on interpretation of EBSD data in order to allocate orientation frequencies based on representative area fractions has been developed. This has been coupled with a polycrystal plasticity RVE framework allowing for arbitrarily sized RVEs and corresponding allocation of crystallographic orientation. This has enabled input of experimentally measured initial textures into the CPFE model allowing for comparison of predictions against measured post-deformation textures, with good agreement obtained. The effect of texture on polycrystal physical properties has also been studied. It has been confirmed that texture indeed has a significant role in determining the average physical properties of a polycrystal. The thesis contributes to the following areas of micro-mechanics materials research: (i) 3D small deformation crystal plasticity finite element (CPFE) modelling, (ii) geometrically necessary dislocation modelling, (iii) 3D large deformation CPFE modelling, (iv) texture homogenisation methods, (v) single and dual phase texture evolution modelling, (vi) prediction of polycrystal physical properties, (vii) systematic calibration of the power law for slip based on experimental data, and (viii) texture analysis software development (pole figures and Kearns factors).
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Xiong, Xinkai. "An Analysis of the Queueing Delays and Throughput of the TCP BBR Congestion Control in NS-3". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-288858.
Testo completoAbstract (sommario):
BBR is a congestion control recently proposed by Google, unlike the traditional congestion control which uses packet loss as the signal of congestion, BBR uses the estimation of bottleneck bandwidth to control the sending rate. However, recent work shows that BBR suffers from a variety of problems such as large queuing delays with multiple flows in the network. Most of the existing work in this area has so far focused on the performance analysis of BBR. Despite these efforts, there exists still a lack of understanding on how to improve the performance of BBR in different scenarios. In this paper, we first present the behaviour of the original BBR in the Network Simulator 3 (ns-3), then, we provide an improvement that carefully adjusts the pacing rate based on the RTT of the flow, finally, to validate our method, we run simulations varying different bottlenecks, latency, and numbers of flows in both small and large buffer size scenarios on ns-3 network simulator. The results show that our improvement can significantly reduce the queuing delay on the bottleneck at a very small cost of throughput in large buffer scenarios, and also achieve less than 0.1% retransmission rate in small buffer scenarios.BBR är en typ av stockningskontroll som nyligen föreslagits av Google. Till skillnad från traditionell stockningskontroll som använder paketförlust som stockningssignal använder BBR en uppskattning av bandbredden i flaskhalsen mellan sändare och mottagare för att styra sändningshastigheten. Senare arbete visar dock att BBR lider av olika problem, såsom långa förseningar i paketköer med flera flöden i nätverket. Det mesta av det befintliga arbetet inom detta område har hittills fokuserat på att analysera BBR-prestanda. Trots dessa ansträngningar saknas det fortfarande förståelse för hur man kan förbättra BBR:s prestanda i olika scenarier. I den här rapporten presenterar vi först beteendet hos den ursprungliga BBR i nätverkssimulatorn ns-3. Därefter föreslår vi en förbättring som noggrant justerar sändningstakten enligt RTT (Round Trip Time) för flödet. Slutligen, för att validera vår metod, utför vi simuleringar som varierar olika flaskhalsar, fördröjningar och antal paketströmmar i små och stora buffertstorlekar i ns-3. Resultaten visar att vår förbättring avsevärt kan minska köfördröjningar i flaskhalsar för stora buffertstorlekar till en mycket låg kostnad i genomströmning, samt uppnå mindre än 0.1% omsändningshastighet i scenarier med små buffertstorlekar.
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Solmaz, Emrah. "Kartläggning av orsaker till skillnad mellan beräknad och uppmätt energianvändning i byggnader. : Identifiering av prioriterade arbetsområden inom energisimulering och energiuppföljning". Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-28752.
Testo completoAbstract (sommario):
As a result of high energy use in buildings, the rules for energy conservation has, since 2006, become stricter in Sweden. Today, it must be verified that buildings meet the requirements of specific energy consumption (energy consumption per square meter heated floor area), with a calculation of the energy performance in a simulation program and by measuring the energy performance when the building is done. This in addition to the requirement that the average coefficient of thermal transmittance and the installed electrical power, for electrically heated buildings, must be calculated at the design stage. It is, however, often noted that the result of the calculations and measurements differ from each other, and that the measured values often are higher than those calculated. In collaboration with NCC and Mälardalens University, an investigation was made in which the calculated and measured values of energy were examined for a number of apartment buildings, schools and sports halls, to identify causes of difference, and to identify priority areas of work within, above all , energy simulation and energy follow-ups. It turned out that the difference is largely influenced by the type of the building, as it differed between apartment buildings, schools and sports halls. In addition, the amount of window area turned out to have impact on the results, as it allows for more airing, which is a factor that is very difficult to anticipate for the simulations. The windows ability to let in sunlight is another factor that is hard to anticipate. Furthermore, it was discovered that the standard values for the assumed energy consumption for domestic hot water is often too high. In some cases the assumed heated floor area and the assumed outdoor climate data differed between calculations and measurements. It also happens that heat losses from culvert pipes to the ground is not taken into account when calculations are done. As for priority areas of work, judging by the results of this work, better behavior related input data and standard values for, above all, energy consumption for hot water needs to be developed. There has to be more diligence when ensuring that there are same conditions for calculations and measurements, and this could mean that those who perform the calculation may need to be assigned more responsibility over the measuring work. In addition, the follow-up work must be envisaged in the long term, which means that the number of registers should be sufficient to distinguish the different parameters, that consumes energy, apart to make it possible to learn from the over-/underestimation, and base future input and standard values on it. This may mean that the simulation-/measure-work should not be limited only to comply with applicable laws, but it should be ensured that follow-up work can be done in such a way that it helps to improve the future work of simulations and measurements of energy use in buildings.
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Puhakka, Fredrik, e Simon Lund. "Energy focus in the building process". Thesis, Högskolan Dalarna, Energiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:du-30422.
Testo completoAbstract (sommario):
Residential buildings have served as homes for the humankind throughout the years and the energy focus is relatively new in comparison. The interest of the energy perspective has increased alongside with the stricter laws and goals in the European Union and the Swedish Building Board. In multiple cases, the calculated energy usage of the buildings are usually lower than the real time measured energy consumption, showing the importance of performing energy follow-ups of the buildings. The goal of this thesis is revolving around the understanding of the the problems, performance and importance of energy follow-ups in the building process. This study will only focus on the energy focus of residential buildings in the building process, while only taking the Swedish laws into consideration. A literature study was performed as an intention to understand the subject and its problems more thoroughly. The literature study contains the Swedish laws regarding the subject, the structure of the building process and possible failure points, while also looking at multiple studies regarding the difference between the calculated and the measured values. Furthermore, inquiries were sent out to multiple municipalities and companies with questions related to the subject. In the answers from the different respondents, the result showed that both municipalities and companies stores energy statistics in web-based programs and requires real measurements to perform energy follow-ups. One municipality describes that there was a vague understanding of the consequences or penalties of not performing an energy follow-up according to the time-plan. Furthermore, the company A described that there was a lack of knowledge of how or where measurements should be performed in detail and where responsibility should be placed if not everything is fulfilled according to the contract. The companies set up their own local goals that surpasses the rules of the BBR and the companies very rarely breaks the energy limits. Company B has only failed to meet the energy limits once and that project was sold off to another actor. Company B also describes that they have never failed to perform an energy follow-up according to the time-plan and doesn’t know what to do if it would happen. Another municipality refers multiple times to their goals regarding the climate and energy limits, however, the methodology on how to achieve these goals aren’t described. Lastly, the there’s no form of cooperation between the municipalities or the companies. Differences in energy performance, between the calculated and the real, is often a result of many different factors, which is not always easy to define. Throughout the building process, it is of high importance to keep focus on the energy question in every step. Good and correct knowledge has to be present the whole process to give the best prerequisites for a good performing building. Bad energy performance leads to higher cost for the habitants. Loose terms in laws and regulations can lead to bad energy calculations and leave room for influencing the calculation to show wanted results. Good energy declarations require proper measurements and as the standard equipment today provides somewhat lacking data with monthly values, which makes it difficult to study the reasons to higher energy consumption. For better understanding abnormal energy consumption, more detailed values are often necessary. In terms of applicability, this study can contribute to the awareness to the different issues that has occurred from the study, for example the required education and the responsibility in more detail. A few conclusions can be made from this study, the lack of knowledge in terms of responsibility, consequences or penalties and how measurements should be made in detail. Another conclusion are that web-based programs are used for energy follow-ups and require real values and there’s no cooperation between different actors related to this subject.Bostäder har använts som hem för människor genom tiderna och energiperspektivet i dessa bostäder är relativt nytt i jämförelse. Energiperspektivets intresse har blivit större samtidigt som hårdare krav och mål har formulerats i EU och i lagboken BBR. I flertal fall är den beräknande energin för en byggnad lägre än den uppmätta mängden under användning, vilket visar vikten av att utföra en så kallad energiuppföljning för respektive byggnad. Målet med detta exjobb handlar om att få en förståelse kring problemen, utförandet och vikten i energiuppföljningar som existerar i flertal fall inom byggprocessen. Den här studien kommer bara fokusera på bostäder i byggprocessen och bara ta hänsyn av de svenska lagarna kring området. En litteraturstudie utfördes för att kunna fördjupa sig inom ämnet och dess problem. Denna litteraturstudie innehåller relevanta svenska lagar för ämnet, strukturen av byggnadsprocessen och möjliga felkällor, men även studera flertal rapporter angående skillnaden mellan den beräknande och den uppmätta energianvändningen. Slutligen skickades flera enkäter till energiexperter i kommuner och företag med relevanta frågor till ämnet. I svaren från respektive respondent visade resultatet att både kommuner och företagen använder dataprogram angående energianvändningen. Dessa dataprogram kräver en verklig uppmätning av energin i hushållen för att kunna utföra en energiuppföljning. Kommun A beskriver att det finns en dålig uppfattning angående de konsekvenser och straffen som förekommer om en energiuppföljning inte utförs i tid enligt tidsplanen. Fortsättningsvist beskriver företag A att det är en begränsad förståelse angående hur och var uppmätningar ska utföras i detalj, men även också vem som ska ta ansvar om någonting går fel enligt byggkontraktet. Företagen sätter upp lokala mål som är lägre än BBRs krav vilket har lett till att fel uppstår väldigt sällan. Företag B beskriver också att de aldrig har misslyckats med att utföra en energiuppföljning enligt tidsplanen men vet inte vad som ska göras om det skulle hända. Kommun B refererar flertal gånger till deras energi- och klimatmål men metodiken av att uppfylla dessa mål är inte beskrivet. Slutligen finns det ingen form av samarbete kring energiuppföljningar mellan de kommuner och företag som har svarat på enkäten. Skillnaden mellan den beräknande- och den uppmätta energiprestandan beror ofta av flertal olika faktorer som är svårt att definiera. Det är viktigt att ha någon form av energifokus genom hela byggnadsprocessen och inte bara i ett fåtal steg. Detta fokus måste vara bra och ha rätt kunskap för att kunna ge de bästa förutsättningarna till en bra bostad från ett energiperspektiv. Byggnader med en dålig energiprestanda leder till en hög kostnad genom förvaltningsfasen. Obestämda termer i lagboken som ”bör” leder till dåliga beräkningar som inte har en liknande struktur och kan vara gjord för att visa ett lägre värde. Energideklarationer som är bra kräver riktiga mätningar och bättre mätningsverktyg som inte ger otillräcklig information i till exempel månadsvärden, vilket leder till en dålig förståelse till vad som händer angående energianvändningen i huset. Användbarheten av studien består till mesta av att upplysa om de problemen som existerar idag som till exempel den behövda utbildningen och kompetensen kring ansvar, straffen och var mätningar ska sättas i detalj. Några slutsatser som studien har kommit fram till är den otillräckliga kunskapen i ansvar, konsekvenser och straff samt mätningar ska sättas beskrivas mer i detalj. Slutligen används dataprogram för att utföra energiuppföljningar som kräver verkliga mätningar och det finns ingen form av samarbetet mellan olika aktörer angående energiuppföljningar.
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Jacobs, Laura A. "The role of RNAs and extracellular vesicles in the radiation response". Thesis, Oxford Brookes University, 2015. https://radar.brookes.ac.uk/radar/items/f3ceff13-e466-4d3d-bb53-6676b79da810/1/.
Testo completoAbstract (sommario):
The bystander effect (BE) occurs when cells that have not been directly traversed by ionizing radiation exhibit DNA damage effects as though they had been. It is established that signalling molecules such as cytokines and reactive oxygen species (ROS) signal to surrounding cells to mediate BE, however more recently it has been demonstrated that extracellular vesicles (EVs) might be involved. In addition, following RNase treatment, the EVs are no longer able to cause DNA damage in unirradiated recipient cells, suggesting that an RNA molecule in association with the EVs is involved with BE. As the literature documenting differential regulation of RNA in EVs released from irradiated cells is scarce, the work described in this thesis has aimed to better understand the role of RNA in the radiation response. Firstly the miRStress database was developed and used to identify novel miRNA candidates involved in response to radiation by meta-analysis of the published literature. Characterisation of the EVs released was also performed using transmission electron microscopy (TEM), sucrose gradient centrifugation, sizing and the determination of EV concentration released from cells. Next-generation sequencing was performed to identify the mRNA, non-coding RNA and microRNA candidates involved. General characterisation of EVs derived from unirradiated and 2 Gy irradiated MCF7 cells was also performed to gain a better understanding of the populations of vesicles released following irradiation. The results herein suggest that EVs from irradiated cells have specific characteristics when compared to those from unirradiated cells. An increase in the number and a decrease in the size of EVs released from 2 Gy irradiated cells were observed compared to unirradiated cell EVs. In addition to the changes in size and release of EVs from 2 Gy cells, EVs released from irradiated MCF7 cells contained specific mRNAs, non-coding RNAs and miRNAs. Furthermore the miRStress database identified microRNA candidates predicted to be involved in the radiation response. Following RNA Seq analysis a functional study of the genes ANP32B, MALAT1, NET1, HSP90AA1 and NCL was performed based upon their upregulation in 2 Gy EVs. Knockdown of some of these genes resulted in changes in the DNA damage response observed in directly irradiated and bystander cells, suggesting that the RNAs carried in irradiated cell EVs do indeed have a functional role in transmission of BE. In summary, this study has identified diverse RNA species in EVs released from irradiated cells that appear to play functional roles in the mediation of the bystander effect. Further investigation would help to elucidate the mechanisms by which these RNAs function in recipient cells in order to better understand the BE mechanism.
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Wellholm, Jill. "Avvikelser mellan beräknad och faktisk energianvändning i byggnader : Fallstudie av en fastighet byggd 2012". Thesis, Uppsala universitet, Fasta tillståndets fysik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-296268.
Testo completoAbstract (sommario):
The Swedish legislation for energy efficiency in buildings established in 2006 presents maximum limits for annual energy use in new buildings. To fulfill these goals the property developer is required to perform an energy calculation beforehand. The regulations also include an independent follow-up of energy use within two years after commissioning of the building. Significant discrepancies between calculated and actual results appear and need to be reduced. In this case study the energy consumption inoperation has been compared to the energy simulations in VIP Energy from the planning phase for a property consisting of four apartment buildings located in Uppsala, Sweden. The property uses a combination of geothermal heating and district heating. A wide approach to identify possible causes was applied, ranging from review of input parameters in the simulation files to evaluation of impact from deviating operation parameters and residential behavior. Furthermore, the thesis highlights the possible impact of the working process with energy calculations and follow-up of energy use in operation. The process was compared to a Swedish industry standard called Sveby, which defines a work plan for energy management in building projects. In the case study the energy use in operation exceeds the simulated results with approximately 63 % for two of the buildings and 44 % for the remaining two. The property uses more district heating than predicted. Possible causes have been identified, for example poor functioning of the heat pump and excluded heat losses in the simulation, but more detailed onsite measuring is needed to confirm the causes. An industry wide systematic approach to extend the monitoring of energy usage inoperation may reduce the deviations in future projects.
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Sjödin, Elin. "Certifiera enligt Miljöbyggnad GULD eller bygga BBR-standard? : En jämförande studie av merkostnaden för projektering och investering för byggherren". Thesis, Luleå tekniska universitet, Industriellt och hållbart byggande, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67619.
Testo completo
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Olsén, Henrik. "Verifiering av en energiberäkningsmodell". Thesis, Linköping University, Linköping University, Department of Management and Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-16373.
Testo completoAbstract (sommario):
Energianvändningen har i Sverige under lång tid varit väldigt hög. Den höga användningen leder till stor miljöpåverkan i form av utsläpp av växthusgaser. Sett bara till elanvändningen är bostadssektorn det område som dominerar. För att på ett enkelt och tillförlitligt sätt kunna beräkna energianvändningen i byggnader används ofta olika sorters energiberäkningsprogram. Detta examensarbete har kretsat kring en egenutvecklad energiberäkningsmodell, kallad Excel-modellen, utvecklad på VVS avdelningen på ÅF i Norrköping. Modellen är anpassad efter ställda krav i Boverkets Byggregler, BBR, och dess huvudsyfte är att beräkna årlig energianvändning och genomsnittlig värmegenomgångskoefficient i byggnader.
Huvudsyftet har varit att på olika sätt verifiera modellen, dels mot annat erkänt energiberäkningsprogram, IDA ICE, och dels mot en verklig byggnad med givna data. Bäst resultat erhölls vid verifieringen mot IDA ICE, med en maximal skillnad resultaten emellan på 6 %. Vid verifieringen mot den verkliga byggnaden blev motsvarande resultat 16 %. Att skillnader i resultat uppkommer i det första fallet var väntat, då den egenutvecklade modellen och IDA ICE räknar på helt olika sätt. IDA ICE är ett dynamiskt program, som tar hänsyn till temperaturvariationer osv., medan modellen är ickedynamisk. Även i det andra fallet var det väntat att skillnader resultaten emellan skulle uppstå. Att få teoretiska resultat att helt överensstämma med verkligheten är svårt, vilket till stor del beror på osäkerhet i indata.
En inventering av marknaden beträffande andra energiberäkningsprogram har gjorts. Detta för att om möjligt kunna visa om det finns andra intressanta program som klarar samma typ av beräkningar som Excel-modellen. Då fokus för inventeringen främst legat i själva kartläggningen av tillgängliga program, uteslöts tester av programmen. Av de studerade programmen kan endast rekommendation ges för IDA ICE, då detta användes vid verifieringsarbetet av Excel-modellen. Trots vissa brister hos Excel-modellen, som framkommit under arbetets gång, kan ändå rekommendationer ges för att använda den framför något annat energiberäkningsprogram.
Även en studie kring olika energilösningar i byggnader har gjorts. Detta för att om möjligt kunna påvisa vilken eller vilka lösningar som är bäst lämpade, dels rent miljömässigt och dels för att klara ställda krav i BBR. För att minska det stora elberoendet i landet bör fjärrvärme användas i de flesta fall. Om man bara ser till att klara ställda krav i BBR, bör någon form av värmepump tillsammans med ett vattenburet distributionssystem användas.
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Palm, Felicia, e Karlsson David Hindersson. "Modulbostäder som en permanent byggnad : En jämförelse av bostadsventilation och krav". Thesis, KTH, Byggteknik och design, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231295.
Testo completoAbstract (sommario):
Sveriges befolkning ökar och i takt med detta behöver fler bostäder byggas. En flexibel lösning till problemet skulle kunna vara modulbostäder. Detta examensarbete undersöker i huvudsak två frågeställningar. Dels hur modulerna står mot de krav som ställts på den svenska byggnadsmarknaden. Dels hur valet av ventilation kan påverka modulbostäderna. Detta genomförs med en jämförelse av kostnader, energiberäkningar och krav mot en referensmodul. Tanken med modulbostäder är att bland annat minska byggtiden genom att producera modulerna i fabrik. Modulerna kan också byggas för att vara möjliga att flytta efter behov. Studien har genomförts genom faktainsamling från litteratur samt intervjuer med ventilationsföretag och företag som jobbar med moduler. Avgränsningar har bland annat gjorts till att bara studera flerbostadshus. Resultatet tyder på att modulbostäder i teorin uppfyller de krav som ställs från bland annat Boverket. Företag satsar mot hållbara byggnader och försöker bygga sina moduler mer som ett vanligt flerbostadshus. Detta ger en längre livslängd och energieffektivare byggnader. Ventilationen visade ett resultat som var svårtolkat. Mycket beror på byggnadens utformning och valet av aggregat från leverantör. Detta tillsammans med vaga värden från ventilationsleverantörerna gjorde det svårt att avgöra vilket system som vore mest fördelaktiga. Val av system kan väljas från mjukare värden som för- och nackdelar. Beroende på om bostäderna behöver vara flexibla så är det att föredra med individuella system. Ser man till kostnad däremot så kan ett centralt system vara med fördelaktigt.The Swedish population is growing and as well the demand for housing construction. A flexible solution to this problem could be modular houses. This thesis examines two main issues. Issue number one focuses on how modular houses can achieve compared to the Swedish standard building regulations. The other issue focuses on how the choice of ventilation system can affect the building. To achieve an answer, comparisons of costs, energy calculations and regulations against an reference housing. The idea with modular housing is to reduce the construction time by building the modules in a industry. A module can also be made portable depending on where it is most needed. This study has been carried through by gathering information from literature and interviews with ventilation- and modular housing companies. Limitations has been made for instance, to apartment buildings. Results show in theory that modular housing compares well to regulations put up by Boverket. Companies working with modular houses has focused more on building modules that can be compared to other types of housing buildings. This gives the modules a longer life span as well as more energy efficiency. It is a bit more difficult to analyze the results from ventilation systems. A lot is depended on the modules design and also the choice of unit. This along with vague data from the ventilation companies made it difficult to choose which system would be more effective. To be able to choose a system from this thesis, softer values like pro and cons to be given in consideration. Depending on the need of the building, different choices could be made. If flexibility is important then a individual system may be preferred. While if cost is more important, then central system should be the choice.
49
Ripert, Pierre-Jean. "Modélisation et identification paramétrique de l'effort de contact pneumatique/sol pour la dynamique véhicule". Nantes, 2006. http://archive.bu.univ-nantes.fr/pollux/show.action?id=7dfc229e-6ee9-466d-bbe3-ca82178b642c.
Testo completoAbstract (sommario):
Les travaux de cette thèse portent sur l’amélioration de la corrélation essai/calcul du pneumatique. Deux axes d’améliorations sont prospectés : la méthodologie d’identification paramétrique et le modèle de pneumatique. La méthodologie d’identification paramétrique est dite « garantie » car elle est basée sur une démarche criticiste. Sur tout type d’excitation (sur banc d’essai ou véhicule), elle permet de caractériser de manière robuste aussi bien la structure que les paramètres du modèle. Le modèle de pneumatique se base sur le formalisme des robots articulés et sur la déformation vue par l’aire de contact. La mise en forme du modèle est réalisée de sorte à être compatible avec les modèles empiriques de spécification des efforts d’interaction pneumatique/sol. On obtient de cette manière un modèle paramétrique qui permet de décrire de manière réaliste et spécifiable le comportement du torseur d’effort appliqué à la base du pneumatique, en statique et en dynamique du premier ordre. Cette méthodologie d’identification et ce modèle de pneumatique sont utilisés pour caractériser différents pneumatiques soumis au banc d’essais de PSA Peugeot Citroën. On identifie de cette manière les comportements observables pertinents. La démarche est illustrée sur les modèles d’effort latéral et du moment d’auto-alignement pour l’agrément de direction. Des mesures sur véhicule sont aussi utilisées pour identifier le modèle d’effort latéral afin de démontrer la validité de la méthode sur des sollicitations dynamiques réellesThis work deals with improvement of tire correlation between real tests and simulations. Two ways are used: in one hand parametric identification methodology and in another hand tire model. Parametric identification methodology is said “guaranteed” because it is designed in a criticism way. Thus with all kind of excitations (from test bench or passenger car), structure model and parameters can be obtained robustly. Tire model is based on the robotic formalism and on empirical specification model of tire/ground interaction forces. The obtained model can be used to specify or to predict tyre static force behaviours and first order dynamics. The developed parametric identification methodology and the tire model are combined to characterise few tires with the PSA Peugeot Citroën test bench. Pertinent and observable behaviours are so deduced. The methodology is applied to cornering force and self aligning torque models dedicated to steering handling. At the end the method is applied to real running car measurements to identify cornering force. It proves the validity of the method both for test bench data and for running car data
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Barbarot, Sébastien. "Étude des déterminants de la dermatite atopique chez le nouveau-né prématuré et à terme". Nantes, 2013. https://archive.bu.univ-nantes.fr/pollux/show/show?id=6dc5952d-a6f0-4702-bb23-69e5cb751ec7.
Testo completoAbstract (sommario):
Les évènements survenant pendant la période périnatale sont susceptibles de modifier le risque de développer une maladie atopique. Nous avons étudié les déterminants précoces de la dermatite atopique (DA) chez le nouveau-né à terme et prématuré dans trois études. La première étude (étude I) est un essai randomisé (n=97) ayant pour objectif d'évaluer l'efficacité d'un lait contenant un symbiotique versus un lait standard sur la croissance et le taux de DA à 6 mois. La croissance était similaire dans les deux groupes mais la proportion d'enfants atteints de DA était plus faible dans le groupe expérimental (p<0,05). De plus, nous avons observé une diminution de la concentration d'IgA sécrétoires fécales entre 1 et 6 mois dans le groupe contrôle et non dans le groupe expérimental. Cette diminution était corrélée au risque de DA et à la colonisation bactérienne intestinale par les bifidobactéries (p<0,014). Dans les études II et III, nous avons évalué l'influence de l'âge gestationnel (AG) et de plusieurs facteurs périnataux sur le risque de DA au sein d'une cohorte nationale d'enfants prématurés nés en 1997 (étude II, cohorte EPIPAGE, n=1836) puis au sein d'une seconde cohorte indépendante régionale récente (étude III, cohorte LIFT, n=493). Après ajustement sur les facteurs confondant, nous avons mis en évidence que les enfants nés très grands prématurés (AG<29 semaines) avaient un risque plus faible de développer une DA à deux ans (cohorte EPIPAGE : ORa 0,57 [IC 95%: 0,37-0,87], p = 0,009) ou cinq ans (cohorte LIFT: ORa 0,41 [IC 95%: 0,18 - 0,90], p = 0,03) comparés aux enfants prématurés nés à un AG plus élevé et aux enfants nés à termeEvents occurring in the earliest stages of development can predispose a child to atopic diseases. We investigated the risk for developing atopic dermatitis (AD) in term and premature neonates in three studies. First we evaluated the safety, tolerance and preventive effect on AD at 6 month of an experimental symbiotic-supplemented infant formula versus standard formula in a randomised controlled trial (study I; n=97). Faecal secretory IgA (SIgA) concentration and microbiota composition of forty-three infants were analysed at 1 and 6 months. Growth was similar in both groups. At 6 months, AD was less frequently observed in the experimental group (P<0. 05). Decrease of faecal SIgA concentration between 1 and 6 months was mainly observed in the control group. This decrease was significantly associated with AD (P< 0. 014) and negatively correlated to the level of colonisation by bifidobacteria (P<0. 005). Then we investigated the relationship between gestational age (GA) and AD using data from two independent population-based cohorts (study II and III), including a total of 2,329 preterm infants, of whom 479 were born extremely preterm (< 29 weeks). After adjusting for confounding variables, a lower GA (< 29 weeks) was significantly associated with decreased risk of AD in the EPIPAGE cohort (aOR: 0. 57 [95% confidence interval (CI): 0. 37-0. 87]; P =. 009) and the LIFT cohort (aOR: 0. 41 [95% CI: 0. 18-0. 90]; P =. 03). So, very low GA (<29 weeks) was associated with a lower risk of AD compared with higher GA (29-34 weeks) and full term birth