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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Modeling Framework to Estimate Airport Runway Capacity in the National Airspace System

Chen, Yueh-Ting 06 February 2007 (has links)
The objective of this study is to estimate the airport capacity in the National Airspace System (NAS). Previous studies have focused on the airport capacity of large commercial airports. This research study estimates the runway capacity for more than two thousand airports in the NAS in order to understand future tradeoffs between air transportation demand and supply. The study presented in this report includes capacity estimates for general aviation and commercial airports. To estimate airport runway capacity, the Federal Aviation Administration (FAA) Airfield Capacity Model (ACM) is used to assess the capacity at all candidate airports in a target airport set. This set includes all airports with potential Very Light Jet (VLJ) operations. The result of the study provides a broad view about the airport capacity in the future air transportation system, and could help decision makers with a modeling framework to identify congestion patterns in the system. Moreover, airport capacity is an important limiting factor in the growth of air transportation demand. The main motivation in our analyis is to include airport capacity constraints in forecasts of air transportation demand. The framework described in this report has been integrated into the Transportation Systems Analysis Model (TSAM). TSAM is a comprehensive intercity and multimode transportation planning tool to predict future air transportation demand. / Master of Science
2

Shy or sociable : introversion/extraversion and message recall

Dvorak, Alana Marie 16 March 2015 (has links)
Personality research has long been an area of interest in the study of consumer behavior. Currently, common practice is to segment prospective audiences by demographic variables (age, gender, and race) instead of psychographics (values, attitudes, personality). In this research, the author investigates the relationship between personality type (introversion/extraversion) and message recall. Using 122 undergraduate and graduate students, recall was examined across two forms of stimulus (incongruent and congruent messages). Results indicated that while there is no relationship between personality type and message recall, there is a relationship between the frequency of advertising messaging and recall. Results are discussed individually by messaging frequency and personality type with further suggestions for future research. / text
3

A Functional Cerebral Systems Approach to Hostility: Changes in Frontal Lobe Delta Activation and Fluency Performance as a Function of Stress

Holland, Alissa Kate 22 July 2008 (has links)
Executive functions, potentially including the regulatory control of emotions and expressive fluency (verbal or design), have historically been associated with the frontal lobes. Moreover, research has demonstrated the importance of cerebral laterality with a prominent role of the right frontal regions in the regulation of negative affect (anger, hostility) and in the generation or fluent production of designs rather than verbal fluency (left frontal). In the present research, participants identified with high and with low levels of hostility were evaluated on a design fluency test twice in one experimental session. Before the second administration of the fluency test, each participant underwent the cold pressor stressor. EEG data collection took place before and after each experimental manipulation. It was hypothesized that diminished right frontal capacity in high hostiles would be evident through lowered performance on this cognitive stressor. Convergent validity of the "capacity model" was partially supported wherein high hostile men evidenced reduced delta magnitude over the right frontal region after exposure to a physiological stressor but failed to maintain consistent levels of right cerebral activation across conditions. The results suggest an inability for high hostile men to maintain stable levels of cerebral activation with stress after exposure to physiological and cognitive stress. Moreover, low hostiles showed enhanced cognitive performance on the design task with lower levels of arousal (heightened delta magnitude). In contrast, reduced arousal (heightened delta magnitude) yielded increased executive deficits in high hostiles as evidenced through increased perseverative errors on the design fluency task. / Ph. D.
4

Demand and Capacity Problems in the Next Generation Air Transportation System

Pu, Davide 23 January 2015 (has links)
This thesis investigates two main aspects of air transportation system, demand and capacity. The first study aims to estimate the potential market for Zip Vehicles, an advanced commuter type of aircraft equipped with automation and electric propulsion technologies. A Multinomial Logit Model was developed to estimate the mode choice behavior of commuters between Zip vehicle, auto and transit in seven metropolitan areas in the United States. The results showed that the Out-of-Vehicle travel time plays an important role in the decision process of commuters. Zip Vehicle is predicted to achieve residual demand with the current technologies and could become more competitive if it was equipped with Vertical Take-Off Technology. The second study developed a hybrid airport runway capacity model that blends both deterministic and simulation techniques. The model includes a graphic user interface that allows high degree of freedom to modify input parameters, such as airport information, weather conditions, minimum separation distances and aircraft grouping system. The model is widely validated and it appears to be a consistent solution for estimating airport capacity at different levels and with various degree of extensibility. / Master of Science
5

Making Memories in 140 Characters or Less: Testing the Effectiveness of CSR Messages Disseminated by Major League Baseball Teams via Twitter on Recognition and Recall

Haugh, Betsy Roberts 24 June 2016 (has links)
Corporate Social Responsibility (CSR) in sport is an emerging area of interest among scholars, sport managers, sponsors, fans, and policy-makers (Breitbarth, Walzel, Anagostopoulos, and van Eekeran, 2015). Despite this increased scholarly attention, a gap in literature exists regarding to the effectiveness of the messages disseminated. This study investigated how sports organizations communicate CSR on Twitter by examining the effectiveness of CSR messages disseminated via Twitter by professional baseball teams. Using priming theory and Lang's (2000) Limited Capacity Model for Mediated Message Processing, this study tested the effects of priming and message sequencing on a persons' ability to recognize and recall these CSR messages. While no statistically significant relationships were found, observed results led to strong arguments about the effects of both priming and message sequencing on the effectiveness of CSR messages disseminated by Major League Baseball (MLB) teams in terms of recognition and recall. Additionally, results suggested that traditional media effects paradigms might not be transferable to social media. / Master of Arts
6

What preschoolers bring to the show: The effects of cognitive abilities and viewer characteristics on children’s learning from educational television

Alade, Fashina 25 July 2013 (has links)
No description available.
7

LOOKING AND LIKING: APPLYING INFORMATION PROCESSING TO FACEBOOK ADS

Ford, Jennie A. 30 May 2014 (has links)
No description available.
8

Making grid capacity available through heat pump control

Arding, Karin, In de Betou, Siri January 2019 (has links)
In this report the problem of constructing a bus depot with electrical buses despite the lack of grid capacity, was analyzed. A potential solution is investigated, namely smart control of heat pumps in industries. The possibility of allocating grid capacity to the bus depot by reducing power consumption in heat pumps during peak hours, is taken into consideration. The maximum amount of released capacity in an industrial area is calculated through the controlling of heat pumps. This investigation was made through simulations with a simplified building energy model (lumped capacity model) which was applied to a reference building. After mapping the area Boländerna and the geothermal wells located there, IKEA Uppsala was chosen as the reference building, since a third of the total number of wells were found in that area. To take the whole capacity of Boländerna into account, the model was scaled up to estimate the total, possible reduction of power. The bus depot requires 6 MW nighttime and 4 MW daytime, the total amount of electrical power that could be withdrawn, if all heat pumps were on maximum heat, in the chosen area were 0.75 MW and by controlling the heat pumps during an optimized level, the amount of 142 kW could be made available to the electric grid. 142 kW is not enough cover the need for the bus depot but it could supply the need for a slow charger to one of the buses and is therefore a possible sub-solution to the larger problem.
9

Prognostisering av produktionskapacitet - En studie på PET-Turbuhaler, AstraZeneca / Forecasting capacity of PET-Turbuhaler production at AstraZeneca

EINARSSON, JOHANNA, SÖDERLUND, HELENA January 2016 (has links)
En viktig aspekt för att få ett företag att bli så framgångsrikt som möjligt är att ha en träffsäker kapacitetsprognostisering av produktionen. En kapacitetsprognostisering hjälper ett företag att förutse och planera sin produktion för att kunna uppfylla den framtida efterfrågan. Därför är det av stor betydelse att prognostiseringen av kapaciteten är träffsäker. Detta är huvudområdet i denna examensrapport. Rapportens författare kom under vårterminen 2016 i kontakt med produktionsenheten PET-Turbuhaler på AstraZeneca i Södertälje. De efterfrågade en träffsäker modell för deras kapacitetsprognostisering på lång sikt, 12-24 månader. Examensarbetets syfte har därför sammanställts i en huvudfrågeställning som lyder; Vilket arbetssätt är det bästa för att PET-Turbuhaler ska uppnå en träffsäker produktionskapacitetsprognostisering på 12-24 månader? För att besvara frågeställningen genomfördes en förstudie, en litteraturstudie samt en intern och en extern benchmarking som alla analyserades och sammanställdes. Förstudien gav en övergripande bild av hur arbetet med den Microsoft Excel-modell som PET-Turbuhaler använder idag fungerar. Dessutom framkom vilka problem som de anställda ser att det finns med den nuvarande modellen. Författarna har även gjort egna analyser av PET-Turbuhalers kapacitetsmodell. Litteraturstudien som gjordes visar bland annat varför det är en skillnad mellan teoretisk och verklig kapacitet. För att beräkna den verkliga produktionskapaciteten behöver anläggningens schemalagda kapacitetsförluster (t.ex. lunch, möten), kapacitetsbortfall (t.ex. maskinhaveri, ställtid) och ej planerad verksamhet (t.ex. defekter) subtraheras från anläggningens teoretiska kapacitetstillgång, d.v.s. när anläggningen är igång dygnet runt, året om. Analysen visade att den modell som PET-Turbuhaler använder idag omfattar i stort sett samma parametrar som den modell litteraturen hänvisar till. Examensarbetarna insåg därför att PET-Turbuhalers problem med en bristande kapacitetsprognos på lång sikt inte nödvändigtvis ligger i den modell som används idag utan snarare i hur modellen används. Det har kommit upp till ytan att parametrar inom den nuvarande modellen inte uppdateras kontinuerligt med aktuell indata. Detta gör att gammal produktionsdata som är inaktuell ligger till grund för den kapacitetsprognos som görs på lång sikt. Frågeställningen kunde besvaras utifrån det underlag som tagits fram i analysen. Det mest intressanta resultatet blev att PET-Turbuhalers kapacitetsprognos på kort sikt inte är lika träffsäker som man tidigare trott. Följden av detta är att ett bra fungerande standardiserat arbete för den korta prognosen behöver utformas för att i framtiden få en träffsäkrare prognos på lång sikt. Efter diskussioner av resultatet kunde examensarbetarna slutligen komma fram till rekommendationer för hur PET-Turbuhaler bör fortsätta arbeta. Några av rekommendationerna är att utvärdera insamlad data kontinuerligt, ha regelbundna möten mellan produktionstekniker och gruppchefer samt att montera en sensor, som kan registrera output-takten, längst ner i flödet på produktionslinorna. / A company needs an accurate capacity plan to become successful. The capacity plan is an important tool for planning and anticipating production which is essential to be able to meet future demands. It is therefore of great importance to get an accurate forecasting of the production capacity, which is the main topic of this report. During the spring semester 2016, the authors of this report were contacted by the production unit PET-Turbuhaler at AstraZeneca in Södertälje. PET-Turbuhaler requested an accurate model for the long term, 12-24 months, forecasting of their production capacity. From this problem, a research question has been formulated into; Which is the best way for PET-Turbuhaler to work to reach an accurate long term, 12-24 months, production capacity prognosis? A pre-study, a literature study and an internal and an external benchmarking were conducted in order to answer the research question. The result from these were afterwards compiled and analyzed. The pre-study at PET-Turbuhaler gave an overview of the work with the current Microsoft Excel-model and its associated problems. The pre-study did also consist of the authors’ own analysis of PET-Turbuhalers capacity model. The literature study was made to investigate how theory advocates the work with capacity forecasting. It showed a difference between theoretical and real capacity. The real capacity is calculated by subtracting the plant’s scheduled and nonscheduled capacity losses (such as time losses for lunch, meetings, set-ups, machine breakdowns and defects from production) from the theoretical capacity. The theoretical capacity of the plant is the capacity when the plant runs 24 hours a day every day of the year. The analysis showed that the current model PET-Turbuhaler use today consist of more or less the same parameters as the literature suggests. The authors could therefore realize that the current model is not necessarily the main problem at this stage. The biggest problem is rather how the current model is being used by the employees. Parameters within the current model are not continuously updated with right data as PET-Turbuhaler thought. The consequence of this is that the long term forecasting is based on out-of-date data even though new and more accurate data is available. The research question can be answered based on the analysis. The most interesting result was the insight that the short term forecasting is not as accurate as PET-Turbuhaler believed. This gives, in order to achieve a good long term forecasting, that PET-Turbuhaler must first improve their short term forecasting by establishing a standardized way of working with the model. Only then can the long term forecasting be accurate. Through discussions regarding the result the authors were able to suggest improvements on how PET-Turbuhaler could work to reach an accurate long term forecast of their production capacity prognosis. The recommendations include continuous evaluation of collected data, regular meetings between production support and production line managers and the benefit of using a sensor, in the end of the production line, to registrate the output rate.
10

Capcal for small roundabouts : Current status and improvements / Capcal för små cirkulationsplatser : Nuvarande situation och förbättringar

Linse, Leif January 2010 (has links)
Questions have been raised regarding how good Capcal works for roundabouts with a weaving length smaller than 25 meters and if Capcal would work for weaving lengths lower than the 16 meters that is the lower limit in the current model. In this thesis, two possible improvements has been developed and tested on five roundabouts with a weaving length less than 25 meters. Work has been done to build alternative gap acceptance models ranging from removal of the 16-meter limit through re-estimation of the current model to a completely new model. In this thesis a new sub model has been introduced that take into account the uncertainty of if circulating vehicles will exit or continue to circulate. These sub models have been combined in 29 different ways including the current Capcal model configuration and have been tested with five different roundabouts. The conflict delay, which is caused by interaction with other vehicles, has been used to compare the model results with delay observations from video captures of the roundabouts.   Out of all model configurations, the original Capcal 3.3 model had the lowest difference in average between the model result and the observations. If the 16-meter weaving length restriction in the original model is removed, almost the same results are obtained as with the restriction. While none of the model configurations improved the model fit, no configuration could be statistically be rejected. In the results of individual roundabouts, there were differences between the model and observations of up to 50%. This shows that while this thesis could not find any improvements of Capcal, there is a potential for future work to develop improvements of the roundabout model. / I nuläget tillåter Capcal att växlingssträckor ner till 16 meter modelleras, men i dataunderlaget som användes vid skapandet av nuvarande modell finns endast med en cirkulationsplats under 25 meter. Det har lyfts frågetecken kring huruvida Capcal ger bra resultat för cirkulationsplatser med en växlingssträcka på mindre än 25 meter samt huruvida modellens nedre gräns på 16 meter skulle kunna tas bort. I detta examensarbete har två olika möjligheter att förbättra modellen testats på fem olika cirkulationsplatser med växlingssträcka kortare än 25 meter. I arbetet har det ingått att ta fram alternativa gap-acceptance-modeller vilka sträcker sig från att enbart ta bort 16-metersgränsen via en nyestimering av Capcals modell till en helt ny modell. Därtill har en ny submodell skapats som tar hänsyn till den osäkerhet som uppstår kring huruvida cirkulerande fordon kommer att köra ur cirkulationen vid en utfart eller fortsätta cirkulera. De utvecklade submodellerna samt nuvarande Capcal modell har kombinerats i 29 olika kombinationer. Dessa 29 kombinationer har för varje av de fem studerade cirkulationsplatserna testats mot observationer från respektive cirkulationsplats. Konfliktfördröjningen, vilket är fördröjning på grund av interaktion med andra fordon, har använts för att jämföra Capcal-resultaten och observationerna.   Av alla modellkonfigurationer så gav nuvarande Capcal 3.3-modell lägst medelskillnad mellan modellresultat och observationer. Om 16-meter-restriktionen i nuvarande Capcal-modell tas bort, så fås i stort sett samma resultat. Ingen av de studerade modell-förändringarna gav en bättre passning mellan modell och verklighet i medel, men ingen förändring kunde förkastas ur statistisk synvinkel. Det var dock stora variationer i resultaten för enskilda cirkulationsplatser med upp till 50% skillnad mellan modellens resultat och observerade värden. Detta visar på att även om detta examensarbete inte lyckades hitta några förbättringar av Capcal, så finns det potential för framtida arbete att ta fram förbättringar av cirkulationsplatsmodellen i Capcal.

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