Modern silencers for heavy vehicle applications are designed to cancel out the sound generated by the effects of combustion and propagation of exhaust gases through the engine after-treatment system. The complex geometry within the compact silencer give rise to self generated (or flow-) noise that contribute to the total sound power radiated at the exhaust outlet. To evaluate the magnitude and spectral frequency content of this self-generated noise, accurate non-reflective boundary conditions need to be applied along with a solver optimized for low dissipation and dispersion of acoustic waves. Parametric studies have been preformed to construct and evaluate the non-reflectiveness of stretched grids in combination with the buffer-zone technique for low- to mid- frequency noise. The Proudman noise source model have been used to identify the sources of sound within the computational domain and Detached Eddy Simulations have been used with full silencer geometries. Finally, the non-reflective performance of the stretched grid and buffer-zone technique have been evaluated using the acoustic beamforming method to spatially filter out and estimate the amount of reflections present in the final simulations. Detached Eddy Simulations can with success be used to resolve flow noise in exhaust gas geometries and allow reasonable comparisons. Steady models have been included in the comparisons but can only be used to estimate the amount of production of acoustic energy, not the radiated sound pressure levels related to the suppression of sound due to flow characteristics within the silencer geometries. Finally, the rough beamforming method confirmed the function of the non-reflective boundary conditions by finding major differences in magnitude for the sound being radiated towards the measurement point in different directions. / Ljuddämpare för lastbilar och bussar är konstruerade för att dämpa det ljud som genereras i förbränningsmotorn och i avgasreningssystemet. Moderna ljuddämpare består av komplexa geometrier som avgaserna flödar igenom och som släcker ut oönskat ljud. När avgaserna, bärandes ljud ifrån förbränningsmotorn flödar i hög hastighet genom den komplexa geometrin alstras ytterligare buller, så kallat själv-genererat ljud. För att ta fram frekensspektrat och ljudtrycksnivån ifrån detta bidragande ljud kan Detached Eddy Simulations utföras. Denna metod av strömningsmekaniska beräkningar kräver dock icke-reflektiva randvilkor. Randvilkor som uppfyller kraven har konstruerats genom parameterstudier tillsammans med en numerisk lösare som med låg dissipation och dispersion beräknar de akustiska pertubationerna i fjärfältet på ett fysikaliskt korrekt sätt. Vidare har även akustiska källmetoder används för att uppskatta närfältets storlek. Magnituden hos de kvarvarande reflektionerna har sedan uppskattas med hjälp av en förenklad Beamforming metod. Detached Eddy Simulations kan på ett framgångsfullt sätt användas för att ta fram det egengenererade ljudet ifrån ljuddämpargeometrier och möjliggör därigenom rimliga jämförelser mellan olika avgasgeometrier. De akusiska källmetoderna kan med säkerhet anvädas för att uppskatta den akustiska effekten som genereras i geometrierna men kan inte användas för att ta fram de dämpande effekterna som turbulenta strukturer eller hastighetsgradienter medför. Den förenklade Beamforming metoden har även bekräftat funtionen hos de icke-reflectiva randvilkoren genom att påvisa stora skillander i den ljudnivån som radierars ifrån olika riktingar mot den punkt som anvädas för att extrahera ljuddämparens ljudtrycksnivå.

Le géothermomètre Δ47 est basé sur la relation entre l’abondance des liaisons 13C–18O des carbonates et la température de calcification. Ce proxy contourne potentiellement les limites des autres thermomètres (δ18O, Mg/Ca) pour reconstruire les paléo-températures des océans, expliquant son développement exponentiel depuis dix ans. Cette thèse teste pour la première fois le potentiel et les limites de la thermométrie Δ47 sur les coccolithes, des nannofossiles calcaires produits par des organismes calcifiants dans la zone photique. Ces biominéraux calcitiques et ubiquistes constituent une part importante de l’archive sédimentaire. Des cultures in vitro nous ont permis d’établir que trois espèces de coccolithes actuelles enregistrent la même relation Δ47 – T que la calcite inorganique, alors qu'elles présentent de très larges effets vitaux en δ18O (±5‰). Nous concluons que ces espèces de coccolithes d'importance géologique ne présentent pas d’effets vitaux en Δ47. Nous avons ensuite appliqué le Δ47 à l’étude des sédiments enregistrant l’événement d’anoxie océanique du Toarcien (–183 Ma) au cours duquel les reconstructions de températures restent encore ambigües, notamment du fait de la méconnaissance de la composition isotopique en oxygène de l’eau de mer. Sur la base des données Δ47 acquises, nous proposons des températures élevées (de l’ordre de 36°C), mais restant relativement stables sur l'intervalle d'étude. En couplant ces températures aux données de δ18O des carbonates, nous suggérons une variation importante du δ18O de l'eau de mer dans le Bassin de Paris lors de la mise en place des faciès black shales. Enfin, sur des sédiments pélagiques subactuels, l’une des espèces étudiées présente des déséquilibres isotopiques en Δ47 non observés en culture et explicables par d’autres paramètres environnementaux comme l’intensité lumineuse. Cette thèse illustre le potentiel du thermomètre Δ47 des coccolithes en différents contextes, ouvrant un vaste champ d’application de reconstruction des paléo-environnements sur le Méso-Cénozoïque / The Δ47 geothermometer relies on the relationship between the 13C–18O abundance in carbonateand temperature of calcification. This proxy has the potential to overcome limitations of other thermometers(δ18O, Mg/Ca) to reconstruct oceanic paleotemperatures. This thesis evaluates for the first time the potentialand the limitations of the Δ47 thermometry of the coccoliths, the calcareous nannofossils produced byorganisms calcifying in the photic zone. These calcitic and ubiquitous biominerals represent an importantpart of the sedimentary archive. In vitro cultures allow us to establish that three modern coccoliths speciesrecord the same Δ47–T relation than inorganic calcite, although exhibiting substantial δ18O vital effects(±5‰). We conclude that these coccoliths species do not present any Δ47 vital effect. We subsequentlyapplied the Δ47 proxy to sediments from the Toarcian oceanic anoxic events (–183 Ma) during which thetemperatures reconstructions are still elusive, mainly due to the unknown oxygen isotopic composition ofseawater. On the basis of our Δ47 data, we infer relatively high, yet steady temperatures (around 36°C) duringthe examined interval. By combining these Δ47-derived temperatures to carbonate δ18O data, we can suggestdrastic change in the seawater δ18O composition in the Paris Basin at the onset of black shale deposition. Acore top calibration of Δ47 of coccoliths revealed that one of the studied cultured species exhibits Δ47disequilibrium that is accountable by other environmental parameters, such as light irradiance in the naturalenvironment. Thus, this thesis illustrates the potential of the coccolith Δ47 thermometer in different settings,opening a wide range of application to reconstruct the palaeoenvironments over the Meso-Cenozoic Eras

L’océan Pacifique est le siège de variabilités climatiques interannuel et multi-décennale, El Niño Southern Oscillation (ENSO) et la Pacific Decadal Oscillation (PDO), dont les répercussions (via des téléconnections) peuvent être mondiales. Des impacts importants sur les populations, les activités socio-économiques et sur l’environnement ont été attribuées à ENSO. Il est alors primordial d’améliorer notre compréhension de la dynamique Pacifique et notamment du phénomène ENSO ainsique son évolution sous l’effet du changement climatique.Les mesures géochimiques (Sr/Ca et 818O) réalisées sur les coraux constituent des enregistrements paléoclimatiques de choix pour l’étude de l’évolution d’ENSO et sont essentielles pour mettre en perspective la dynamique actuelle du climat par rapport à sa dynamique passée. Après avoir évaluer la robustesse du paléothermomètre géochimique corallien (Sr/Ca), cette thèse a permis la reconstruction de température de surface océanique (SST) à partir de coraux de l’atoll de Clipperton (Pacifique tropical Est) et de l’archipel des Marquises (Pacifique tropical centre) couvrantplusieurs parties du dernier millénaire. Nos résultats suggèrent que la structure spatiale d’ENSO étaitplutôt stable au cours des deux derniers siècles, montrant majoritairement une structure de type ENSOcanonique (Est Pacifique) par opposition à l’ENSO Modoki (centre Pacifique). Bien qu’encore débattue, cette structure spatiale pourrait avoir évoluée très récemment, en liaison avec le changement climatique global (et cela pourrait continuer dans le futur). A l’échelle décennale, nos deux zones d’étude (centre et Est Pacifique) sont influencées par la PDO.Les résultats de cette thèse tendent également à suggérer que l’activité d’ENSO actuelle (sous l’effet du forçage anthropique) n’est pas atypique à l’échelle du dernier millénaire. En effet, son intensité et sa fréquence étaient plus fortes au début du petit âge glaciaire (LIA, 16ème siècle). La comparaison deces résultats avec un ensemble de simulations climatiques (PMIP3) montre que la variabilité ENSO estbien reproduite par ces modèles climatiques mais qu’ils échouent à reproduire correctement l’état moyen des températures du Pacifique. / The Pacific Ocean is the place of interannual and multi-decadal climate variabilities, namely the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO). There can have globals impacts via teleconnections. Major impacts on populations, economic and environmental activitieshave been attributed to ENSO. It is therefore essential to improve our understanding of the Pacificdynamic, particularly ENSO activity and its evolution under recent climate change.Geochemical measurements (Sr/Ca and 818O) performed on corals are relevant paleoclimatic records for studying the evolution of ENSO and are essential to put into perspective the current climatedynamic in comparison to past climate.After an evaluation of the robustness of the coral geochemical paleothermometer (Sr/Ca), we present the reconstruction of sea surface temperature (SST) from Eastern tropical Pacific coral (Clippertonatoll) and central tropical Pacific coral (Marquesas archipelago) covering several parts of the last millennium. Our results suggest that ENSO spatial pattern was relatively stable over the past two centuries, mainly indicating an eastern Pacific ENSO pattern (canonical) in comparison to the centralPacific ENSO (Modoki). Although still debated, this spatial pattern could have recently changed dueto global climate change (and this could continue in the future). At the decadal timescale, both studiedareas (central and eastern Pacific) are influenced by the PDO.The results of this Phd thesis also suggest that the present day ENSO activity (under the influence ofanthropogenic forcing) is not atypical throughout the last millennium. The intensity and frequency of ENSO were stronger in the early Little Ice Age (LIA, 16th century). These results are compared withan ensemble of climate simulations (PMIP3) and indicate that ENSO variability is correctly reproduced by numerical climate models but that these models fail to correctly reproduce the mean temperature state of the Pacific.

The purpose of this study was to examine the relationshipsbetween the customer value factors control, self-efficacy,independence and time efficiency when using self-servicetechnology. Through increased knowledge of theserelationships, service meetings with self-service technologycan be improved. This qualitative study examines a selfservice technology and collects empirical material throughobservations and semi-structured interviews. In order toobtain a theoretical basis, previous research on the currentrelationships has been investigated and compiled. Theresults of the study confirmed the developed conditionsfrom the theoretical basis and that they affect users'performance and satisfaction when interacting with selfservice technologies. In addition, the study generated newknowledge, a further relationship between self-efficacy andcontrol was found and that external factors such asexperience, environment and stress are importantcomponents that also have an impact on the use of selfservice technology. However, in future research it may benecessary to focus also on external factors to create a fairpicture of these relations but also additional customer valuefactors such as fun and availability. / Syftet med denna studie var att studera förhållanden mellankundvärdesfaktorerna kontroll, självförmåga,självständighet och tidseffektivitet vid användning avsjälvbetjäningssystem. Genom ökad kunskap om dessaförhållanden kan servicemöten med självbetjäningssystemförbättras. Denna kvalitativa undersökning undersöker ettsjälvbetjäningssystem och samlar in empiriskt materialgenom observationer och semi-strukturerade intervjuer. Föratt få en teoretisk grund har tidigare forskning kring deaktuella förhållandena undersökts och sammanställts.Resultatet ur studien bekräftade de framtagna förhållandenur den teoretiska grunden och att de påverkar användaresprestationer och tillfredsställelse vid interaktion medsjälvbetjäningssystem. Dessutom genererade studien i nykunskap i form av att ytterligare ett förhållande mellansjälvförmåga och kontroll framställdes samt att yttrefaktorer som vana, miljö och stress är viktiga beståndsdelarsom även dem har en inverkan på användningen avsjälvbetjäningssystem. I framtida forskning kan det dockvara nödvändigt att fokusera även på yttre faktorer för attskapa en rättvis bild av dessa förhållanden men ocksåytterligare kundvärdesfaktorer som nöje och tillgänglighet.

I dagens samhälle gömmer det sig en teknologi som inte alla tänker på, nämligen Self-Service Technology(SST). Self-Service Technology befinner sig ofta i ens närhet. Företag använder sig av denna teknik för att tillfredsställa deras kunder snabbare och smidigare. Denna studie har utförts på Monitors ERP System AB:s Online-hjälp genom en kvantitativ metod. Syftet med denna studie var att utvärdera betydelsen av de olika dimensionerna i Self-Service Technology (SST) för kundtillfredsställelse. För att sedan generera ny kunskap och förslag för förbättringar av SST och webbaserade kundsupportsystem. För att genomföra denna studie användes en explorativ faktoranalys på de 7 dimensioner inom Self-Service Technology samt dimensionen kundtillfredsställelse. Resultatet visade att de två dimensionerna funktionalitet och bekvämlighet hade starkast koppling till dimensionen kundtillfredsställelse. Därför bör verksamheter liknande Monitors ERP System AB fokusera på att förbättra funktionalitet och bekvämlighet dimensionerna för att uppnå bättre kundtillfredsställelse. / In today's society, there is a technology that not everyone thinks about, namely Self-Service Technology (SST). Self-Service Technology is often in one's vicinity. Companies use this technology to satisfy their customers faster and more smoothly. This study was performed on Monitor's ERP System AB's Online help using a quantitative method. The purpose of this study was to evaluate the importance of the different dimensions of Self-Service Technology (SST) for customer satisfaction. To then generate new knowledge and suggestions for improvements to SST and web-based customer support systems. To conduct this study, an exploratory factor analysis was used on the 7 dimensions within Self-Service Technology and the dimension customer satisfaction. The results showed that the two dimensions functionality and convenience had the strongest connection to the dimension customer satisfaction. Therefore, businesses similar to Monitor's ERP System AB should focus on improving the functionality and convenience dimensions to achieve better customer satisfaction.

This thesis aims to provide the thermal condition of melt pool convection by CFD simulation, which is important to the assessment of the invessel melt retention (IVR) strategy widely adopted in Generation III pressurized water reactors (PWRs). As a severe accident mitigation measure, the IVR strategy is realized through external cooling of the lower head of a reactor pressure vessel (RPV). To achieve the coolability and retention of the corium pool in the RPV lower head, the heat flux at the outer surface of the vessel should be less than the critical heat flux (CHF) of boiling around the lower head. Under such condition, the integrity of the RPV is guaranteed by the adequate thickness of the unmelted vessel wall. The thesis work starts from the selection and validation of a turbulence model in the CFD computational tool chosen (Fluent). Afterwards a numerical model is set up for estimation of melt pool heat transfer of a reference PWR with the power capacity of 1000 MWe, including a mesh sensitivity study. Based on the numerical model of a twolayer melt pool, four tasks are carried out to investigate the effects of Zr oxidation ratio, Fe content, and radiation emissivity on heat flux profiles, as well as the focus effect under extreme conditions. Selection and validation of the turbulence model are conducted by comparing the simulation results of different turbulence models with the DNS data on the convection of volumetrically heated fluid layer bounded by rigid isothermal horizontal walls at equal temperature. The internal Rayleigh numbers of the flow reach up to 10e6. The comparison shows a good agreement of the SST k-ω turbulence model results with the DNS data. The simulations with the Zr oxidation ratio of 0, 0.2 and 0.5, correspondingly, the oxide layer of 1.389m, 1.467m and 1.580m, and the metal layer of 0.705m, 0.646m and 0.561m in height, show that, the temperature of the oxide layer will increase with Zr oxidation ratio, while the temperature of the metal layer will decrease resulting in more heat transfer through the oxide layer sidewall and less top radiation. Nevertheless, the effect of the Zr oxidation ratio is not pronounced in the range of 00.5. The simulations with the Fe mass of 22t, 33t and 45t, and respective height of the metal layer of 0.462m, 0.568m and 0.646m, show that, the inner metal layer will significantly increase the temperatures of both the metal layer and the oxide layer. The percentage of heat transfer at the oxide layer sidewall will increase to supplement the reduction of that at the metal layer. The simulations with the radiation emissivity of 0.2, 0.35, 0.45 and 0.7 show that, the emissivity below 0.45 has an impact on heat transfer, and the temperatures and sidewall heat flux of both the oxide layer and the metal layer will increase with decreasing emissivity. The impact is negligible when the emissivity is above 0.45. The simulations under the hypothetically extreme conditions with either an adiabatic top boundary or a very thin metal layer show the focusing effect may occur, i.e., the heat flux through the metal sidewall is larger than that in the oxide layer. But the local high heat flux is flattened by the vessel wall with good heat conductivity. In summary, the simulations demonstrate that, except for the cases under extreme conditions, the heat fluxes of the melt pools in all other cases are significantly lower than the CHF of external cooling of the lower head. Therefore, the safety margin of the IVR strategy of the PWR chosen is seems sufficient. However, due to some limitations (e.g., simplification and assumptions) in the simulation cases and coupling of different influential factors, as indicated by the present study, the precise predictions of heat flux under all scenarios are still difficult. Therefore, the conclusions could not be generalized to the other conditions or other configurations of the molten pools. By discussing the model and simplifications/assumptions adopted in this work, the improvement directions of the numerical model and other perspectives are proposed at the end of the thesis. / Denna avhandling syftar till att tillhandahålla det termiska tillståndet för smältbassängskonvektion genom CFD-simulering, vilket är viktigt för bedömningen av IVR-strategin som allmänt antagits i tryckvattenreaktorer (PWR) i Generation III. Som en åtgärd för att mildra allvarliga olyckor realiseras IVR-strategin genom extern kylning av det nedre huvudet av ett reaktortryckkärl (RPV). För att uppnå kylbarhet och kvarhållning av koriumbassängen i det nedre RPV-huvudet bör värmeflöde vid den yttre ytan av kärlet vara mindre än det kritiska värmeflödet (CHF) som kokar runt det nedre huvudet. Under sådant tillstånd garanteras RPV: s integritet av den osmälta kärlväggens tillräckliga tjocklek. Examensarbetet startar från valet och valideringen av en turbulensmodell i det valda CFD-beräkningsverktyget (Fluent). Därefter sätts en numerisk modell upp för uppskattning av smältbassängens värmeöverföring av en referens PWR med en effektkapacitet på 1000 MWe, inklusive en nätkänslighetsstudie. Baserat på den numeriska modellen för en tvålagers smältbassäng utförs fyra uppgifter för att undersöka effekterna av Zr-oxidationsförhållande, Fe-innehåll och strålningsemissivitet på värmeflödesprofiler, liksom fokuseffekten under extrema förhållanden. Val och validering av turbulensmodellen utförs genom att jämföra simuleringsresultaten för olika turbulensmodeller med DNS-data för konvektionen av volymetriskt uppvärmt fluidskikt avgränsat av styva isoterma horisontella väggar vid lika temperatur. De interna Rayleigh-siffrorna i flödet når upp till 10e6. Jämförelsen visar att SST k-ω turbulensmodellresultaten överensstämmer med DNS-data. Simuleringarna med Zr-oxidationsförhållandet 0, 0,2 och 0,5, motsvarande oxidskiktet på 1,389 m, 1,467 m och 1,580 m, och metallskiktet på 0,705 m, 0,664 m och 0,561 m i höjd, visar att temperaturen av oxidskiktet kommer att öka med Zr-oxidationsförhållandet, medan metallskiktets temperatur kommer att minska vilket resulterar i mer värmeöverföring genom oxidskiktets sidovägg och mindre toppstrålning. Ändå är effekten av Zr-oxidationsförhållandet inte uttalad i intervallet 00,5. Simuleringarna med Fe-massan på 22t, 33t och 45t och respektive höjd av metallskiktet på 0,462m, 0,568m och 0,664m visar att det inre metallskiktet avsevärt kommer att öka temperaturerna för både metallskiktet och oxiden lager. Andelen värmeöverföring vid oxidskiktets sidovägg ökar för att komplettera minskningen av den vid metallskiktet. Simuleringarna med strålningsemissiviteten 0,2, 0,35, 0,45 och 0,7 visar att emissiviteten under 0,45 påverkar värmeöverföringen, och temperaturerna och sidoväggens värmeflöde för både oxidskiktet och metallskiktet kommer att öka med minskande emissivitet. Effekten är försumbar när strålningen är över 0,45. Simuleringarna under de hypotetiskt extrema förhållandena med antingen en adiabatisk övre gräns eller ett mycket tunt metallskikt visar att fokuseringseffekten kan uppstå, dvs. värmeflödet genom metallsidan är större än det i oxidskiktet. Men det lokala höga värmeflödet plattas ut av kärlväggen med god värmeledningsförmåga. Sammanfattningsvis visar simuleringarna att, förutom fall under extrema förhållanden, är värmeflödet från smältpoolerna i alla andra fall betydligt lägre än CHF för extern kylning av nedre huvudet. Därför verkar säkerhetsmarginalen för IVR-strategin för den valda PWR tillräcklig. På grund av vissa begränsningar (t.ex. förenkling och antaganden) i simuleringsfall och koppling av olika inflytelserika faktorer, vilket indikeras av den aktuella studien, är de exakta förutsägelserna av värmeflöde under alla scenarier fortfarande svåra. Därför kunde slutsatserna inte generaliseras till de andra förhållandena eller andra konfigurationer av de smälta poolerna. Genom att diskutera modellen och förenklingar / antaganden som antagits i detta arbete föreslås förbättringsriktningarna för den numeriska modellen och andra perspektiv i slutet av avhandlingen.

This qualitative study investigates how check-in and check-out self-service technology (SST)for hotels affects the hotel experience of young hotel guests. Following study also focuses onevaluating whether the current SST technology meets the expectations of these young guests.As the hospitality industry in Sweden increasingly adopts SST solutions, understanding theperceptions and satisfaction levels of young guests becomes essential for hotels striving toenhance their service quality. The research employs a qualitative approach, utilizingsemi-structured interviews as the primary data collection method. Twenty respondents, agedbetween 20 and 28 years, were interviewed to gain in-depth insights into their experienceswith SST technology for check-in and check-out processes. / Denna studie undersöker hur självserviceteknologi (SST) på hotell i form av in- ochutcheckning påverkar hotellupplevelsen för unga hotellgäster. Studien fokuserar också på attutvärdera om den befintliga SST-teknologin uppfyller förväntningarna hos dessa unga gäster.I takt med att svenska hotellbranschen i större utsträckning börja använda SST-lösningar blirdet viktigt att förstå unga gästers uppfattningar och serviceupplevelser för att hotellen skakunna förbättra sin servicekvalitet. Studien utgår från en kvalitativ metod medsemistrukturerade intervjuer som primär datainsamlingsmetod. Tjugo respondenter i åldern20 till 28 år intervjuades för att få djupgående insikter i deras upplevelser av SST-teknologiför in- och utcheckning på hotell.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Central Test and Evaluation Incentive Program, (CTEIP) is developing Integrated Network Enhanced Telemetry (iNET) to extend serial streaming telemetry (SST) with a command and control link. Command link interfaces link remote Advanced Range Telemetry (ARTM) transmitters (Tx) and receivers (Rx), developed under the ARTM CTEIP project, via graphical user interfaces (GUI). The communication channel links the iNET Tx on a vehicle network (vNET) and the iNET Rx on a ground station network (gNET) via a single GUI. The command link is an essential part of the pending iNET Technology Demonstration.

O objetivo deste estudo foi analisar a variabilidade climática espectral da temperatura da superfície do mar, TSM, global associada a oscilações de 1-12 meses, 1-2 anos, 2-4 anos, 4-8 anos e 8-12 anos, entre1854 e 2014, e, as possíveis relações com a variabilidade climática na América do Sul. A análise espectral da TSM foi obtida com a aplicação da técnica de ondeletas a dados mensais. Em termos globais, as bacias tropicais do Pacífico Norte e Sul apresentam os sinais mais intensos da variância de TSM, em todas as faixas espectrais consideradas, e, portanto, valores mais próximos da média global para os trópicos, indicando a importância do oceano Pacífico no clima global. Nesta ordem, as bacias do Pacífico Sul, Pacífico Norte, Atlântico Norte, Indico e Atlântico Sul apresentam valores decrescente de variância da TSM. A análise da tendência linear ao longo do período considerado mostra que, globalmente, fenômenos tropicais com oscilações nas escalas de frequências mais altas, 1-12 meses, 1-2 anos e 2-4 anos, têm apresentado decréscimo de energia e que fenômenos com oscilações nas escalas de frequências mais baixas, 4-8 e 8-12 anos, têm apresentado aumento de energia, o que sugere a troca de energia entre fenômenos de alta e baixa frequência . As oscilações de 2-4 anos e de 4-8 anos na região equatorial do Pacífico são as que apresentam os maiores valores de energia, em especial nas regiões de Ninõ1+2, Niño3, Niño3.4 e Niño4. Os resultados permitem verificar que eventos fortes de El Niño sempre estiveram associados a sinais intensos da variância de TSM nas faixas espectrais de 2-4 anos e 4-8 anos e que os eventos mais fracos de El Niño estiveram associados à faixa de oscilações mais rápidas, 1-2 anos. O início do aumento do valor da variância de TSM para oscilações de 2-4 anos e 4-8 anos na região equatorial do Pacífico apresenta, em todos os casos, antecedência significativa em relação à ocorrência de um evento de El Niño forte, indicando a possibilidade de usar este sinal como preditor da ocorrência de eventos quentes de ENOS. A associação entre a variabilidade da variância espectral de TSM e a variabilidade climática na América do Sul foi verificada com base nos dados precipitação do GPCC, dados de vento das reanálises I e II do NCEP-NCAR e da reanálise do JRA-55. A análise de ondeletas da TSM tropical para a faixa de oscilações de 4-8 anos possibilitou a divisão do período todo em fases distintas: fases positivas, 1948 a 1960 e 1982 a 2003 e fases negativas, 1961 a 1981 e 2004 a 2014. Observou-se que as fases positivas e negativas apresentam um padrão bipolar da precipitação entre as regiões nordeste e sudeste da América do Sul, o que está associado a anomalias contrárias da circulação atmosférica em altos e baixos níveis sobre a região central do continente, constituindo um resultado inédito na área de climatologia. As fases positivas da variância de TSM para oscilações de 4-8 anos estão associadas a anomalias negativas e positivas de precipitação, respectivamente, sobre as regiões nordeste e sudeste da América do Sul enquanto que as fases negativas estão associadas a padrões contrários. O padrão do 4º modo da Análise de Componentes Principais aplicada aos dados de vento em 200 hPa contribui para explicar fisicamente o padrão bipolar da precipitação observado no setor leste do continente na escala decadal, por meio da propagação de ondas de baixa frequência entre o Pacífico Sul e a América do Sul. / The aim of this study is to analyze the global SST spectral climate variability for 1-12 month, 1-2 year, 2-4 year, 4-8 year, and 8-12 year oscillations, in the period from 1854 to 2014, and the possible relations with the climatic variability in South America. The spectral analysis of SST was obtained with the application of the wavelet technique to the monthly data. In global terms, the North and South Pacific basins show the most intense signs of SST variance in all the spectral ranges considered, and therefore, values closer to the global average, indicating the importance of the Pacific Ocean in the global climate. Then, in order of importance, come the basins of the South Pacific, the North Pacific, the North Atlantic, the Indian Ocean and the South Atlantic. The analysis of the linear trend throughout the period considered shows that globally within the tropical range, phenomena with oscillations in the scales of higher frequencies, 1-12 months, 1-2 years, and 2-4 years, have decreased energy and that phenomena with oscillations at lower frequency scales, 4-8 and 8-12 years, have presented increased energy through the course of time, suggesting energy exchange between high frequency phenomena and low frequency phenomena. The 2-4 year and 4-8 year oscillations in the equatorial Pacific region are those with the highest energy values, especially in the Nin1 + 2, Niño3, Niño3.4 and Niño4 regions. It is also possible to verify that strong El Niño events have always been associated with intense SST variance signals in the 2-4 year and 4-8 year spectral bands, and the weaker El Niño events were associated with the 1-2 year spectral bands. The beginning of the increase in the SST variance value for 2-4 year and 4-8 year oscillations in the equatorial region of the Pacific presents, in all cases, significant antecedence in relation to the occurrence of a strong El Niño event, indicating the possibility of using this signal as a predictor of the occurrence of hot ENSO events. The association between SST spectral variance variability and climatic variability in South America was verified based on GPCC precipitation data and wind data from NCEP-NCAR I and II reanalyses and of the JRA-55 reanalysis. The analysis of tropical SST wavelets for the 4-8 year oscillation range allowed the division of the whole period into distinct phases: positive phases, 1948 to 1960 and 1982 to 2003; and negative phases, 1961 to 1981 and 2004 to 2014. It was observed that positive and negative phases present a bipolar precipitation pattern between the Northeast and Southeast regions of the AS, which is associated with anomalies of atmospheric circulation at high and low levels over the central region of the continent, which is an unprecedented result area of climatology. The positive phases of the SST variance for 4-8 year oscillations are associated with negative and positive precipitation anomalies respectively over the northeast and southeast regions of South America while the negative phases are associated with contrary precipitation patterns. The 4th mode pattern of the Principal Component Analysis applied to wind data at 200 hPa contributes to physically explaining the bipolar pattern of precipitation observed in the eastern sector of the continent on the decadal scale by propagating low frequency waves between the South Pacific and South America.

This research explores the relationship between intention and actual usage of self-service technology (SST), and investigates the effects of facilitating conditions and customer readiness on customer adoption of SST. In recent years, self-service technologies have created many new service contents; nevertheless, the actual utilization is not actually common yet. Therefore, this research try to explore the relationship between customer readiness and facilitating conditions on the actual use of SST, then focus on narrowing the gap between intention to use SST and actual usage of SST. We believe that this understanding is imperative for service providers to make proactive strategies for fostering customers’ intention and actual usage of the SST. The framework makes it possible to understand and predict customer trial related to using self-service technology by thoroughly examining underlying customer readiness degree and use the internet to illustrate how our framework can be applied to study customer behavior related to a specific self-service technology. To analyze the longitudinal effect, a two-stage survey was conducted and lasted for seven months. As it is well known that behavior intention does not necessary lead to actual behavior, our findings offer proactive strategies to service providers in turning intention into actual usage. Implications are discussed for managerial strategy as well as for future research. The research can be referred as marketing strategy for self-service or kiosk industry, and on academic contribution of narrowing the gap between intention and actual use. It is expected that it is helpful to facilitate self-service development and to enrich customer experience and competitiveness in Taiwan.