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8631 Uppsatser om Holt-Winter´s Method - Sida 1 av 576

Utvärdering av Transportstyrelsens flygtrafiksmodeller

The Swedish Transport Agency has for a long time collected data on a monthly basis for different variables that are used to make predictions, short projections as well as longer projections. They have used SAS for producing statistical models in air transport. The model with the largest value of coefficient of determination is the method that has been used for a long time. The Swedish Transport Agency felt it was time for an evaluation of their models and methods of how projections is estimated, they would also explore the possibilities to use different, completely new models for forecasting air travel. This Bachelor thesis examines how the Holt-Winters method does compare with SARIMA, error terms such as RMSE, MAPE, R2, AIC and BIC  will be compared between the methods. The results which have been produced showing that there may be a risk that the Holt-Winters models adepts a bit too well in a few variables in which Holt-Winters method has been adapted.

Prognostisering av försäkringsärenden : Hur brytpunktsdetektion och effekter av historiska lag? och villkorsförändringar kan användas i utvecklingen av prognosarbete

I denna rapport presenteras ett tillvägagångssätt för att hitta och datera brytpunkter i tidsserier. En brytpunkt definieras av det datum då det skett en stor nivåförändring i tidsserien. Det presenteras även en strategi för att skatta effekten av daterade brytpunkter. Genom att analysera tidsserier över AFA Försäkrings ärendeinflöde visar det sig att brytpunkter i tidsserien sammanfaller med exogena händelser som kan ha orsakat dessa brytpunkter, till exempel villkors- eller lagförändringar inom försäkringsbranschen. Rapporten visar att det genom ett metodiskt angreppssätt går att skatta effekten av en exogen händelse.

Utvärdering av olika diagnostiska metoder för infektioner med bovint coronavirus hos nötkreatur :

This paper shortly describes the coronavirus family, bovine corona viruses (BCV) properties and two diseases that BCV causes, winter dysentery and calf diarrhoea. The purpose of the study was to compare different diagnostic methods to detect BCV. Different methods are discussed, PCR, ELISA, immunofluorescense and virus isolation. Investigations were made in three different herds with winter dysentery; one dairy cattle farm with about 100 cows of different ages, one testing station for bulls with about 150 bulls and another small dairy cattle farm with 26 cows and 20 replacement heifers and calves. Faeces and nasal swabs were analysed with PCR and ELISA. The result shows that PCR seems to be a reliable method for detecting BCV but that the ELISA test can not be used as a reliable diagnostic method to analyse samples from animals with winter dysentery..

Betongarbeten under vintertid : Fokusering på platsgjuten betong

This report is on concrete work during the winter and is implemented on Peab?s behalf. The assignment was to describe the differences between a summer- and a winter casting. While it shows the complications that exists, it also show what aids are available, both electronic via computer and physical aids.The information that I have developed is originally from theory in books, information on the internet as well as practical experience from knowledgeable people that works in construction output. Other theories are those I have learned throughout the education to become a construction engineer, including all oral sources over the years.The results I have come up with, I hope will be able to help future construction projects in the planning phase of a winter casting.

Etablering av höstraps i mellansverige :

The production of oilseed rape is an important issue in Sweden and those who never have grown oilseed rape (OSR) are now willing to try. It is always a risk to grow oilseed rape, specially winter OSR, because of outwintering. This risk increases as you go north and therefore establishment and autumn growth is very important. These are some of the reasons that I have chosen to write about the establishment of winter oilseed rape in Middle Sweden. There are many factors that influence the outcome of the establishment, e. g.

Älgbetesinventering på Orsblecks viltvårdsområde

The purpose with this report is to compare moose browsing in young stands within a small game preservation, and if there are any differences between two areas. The method used in the inventory is a local damage caused by moose browsing survey. It is suitable on areas that have more than 50 hectares but less than 250 hectares of young forest. Inventory of moose browsing is best done on bare ground in the spring and should preferably be done before the flushing begins at the pine. Orsblecks game management area is divided into two different moose management areas, Noppikoski and Siljansringen. During the winter Siljansringen has a denser winter strain of moose, because of the moose seek out lower parts with less snow during the winter. This should also lead to the southernmost part should accommodate larger proportion of damages caused by browsing by moose.

Korttidsprediktering av restider med Holt-Winters metod

Trafiken på våra vägar ökar stadigt och det finns inga tecken på att denna trend kommer att brytas. Denna utveckling innebär en mängd problem såsom ökat buller, mer utsläpp och ökad trängsel. En lösning på trafikproblemen är att utnyttja de befintliga vägarnas kapacitet på ett bättre sätt. Genom att få bilisterna att välja alternativa vägar, resa på andra tidpunkter eller välja alternativa transportmedel kan trängseln på våra vägar minska och därmed minskar också utsläpp och buller. Ett sätt att påverka bilisterna är genom att förmedla information om, exempelvis, rådande trafikförhållande och alternativa resvägar.

Tjäderns (Tetrao urogallus L.) vinterdiet i norra Sverige : är gran (Picea abies) viktig i vissa habitat?

In Scandinavia, capercaillie are often associated with pine trees (Pinus sylvestris) in winter, with pine needles as the main diet. Few dietary studies have been conducted in Sweden and winter diet is subject to little debate. The interesting thing is that this "pine specialist? is also found in spruce (Picea abies) forest habitats where pine is scarce or unavailable. In many studies outside Sweden (primarily Central Europe) spruce is regularly observed in the winter diet, but I have found no reports on the selection of the diet in spruce forest areas in Sweden.

Betydelsen av skogens ålder och förekomst av lavar för renars val av vinterbetesområde :

This is a study on winter groups, ?siida?, of semi-domesticated mountain-migrating reindeers that move to lichen pastures in the lowland boreal forests during winter. The aim of the study was to determine reindeer habitat use in their winter ranges in a managed forest landscape. The reindeers use of three different types of forests was determined, 1) 100-130 year old, 2) 20-40 year old forest and 3) clear-cut areas. All sites were dominated by Scots pine, Pinus sylvestris, and had the same types of ground vegetation.

Med tanke på vintern : ett gestaltningsförslag för Broparken i Umeå

It may seem obvious that the urban space in our northern cities should be design to function and inspire throughout the whole year. This is not always the case. The urban space is often designed on a summer basis and the winter is regarded more as a problem then a resource and its potential remain unused. I have in this master thesis studied the impact of the winter on people and spaces and ponder on how to design functional and attractive places for winter. The project ends in a design concept for Broparken in Umeå on the theme "everyday winter day". The work with this thesis has given me, as a landscape architect, valuable experiences and filled a gap of knowledge that I had in this subject. I hope that this thesis can inspire Umeå kommun and others who are interested in how northern cities can benefit by its climate and develop towards a more complete city. The thesis begins with a chapter that present the subject from four different perspectives.

Etablering av höstvete med reducerad jordbearbetning :

The payment for produced grain is constantly going down in price. It is important for farmers to become more effective in cultivating more land in a shorter time perspective. At the same time we have to calculate with the risk of getting lowered subsidies from the EU. This is why I would like to find out the possibilities for establishing winter wheat without ploughing. I hope to find a difference in the number of plants due to different soil preparations. With this experiment I expect to find out whether I can establish winter wheat at a lower cost, with the same numbers of plants per square meter.

Fundamentala faktorers förklaringsgrad och simuleringsmöjligheter gentemot elspotpriset på Nord Pool : Utsläppsrätternas betydelse för elspotpriset under andra handelsperioden

The purpose of this study is to evaluate the relation between certain chosen fundamental factors (emission trading rights, hydrological balance, interaction with continental Europe, fuel prices) and the spot price at Nord Pool. Particular focus has been put on the trade with emission rights since it is only now their actual impact on electricity prices can be studied. The relationships are measured with regression analysis which includes both R2 and the simulation possibilities of ARX models. The studied period covers 2008 and 2009 with partly daily data and partly weekly data. Owing to the expected higher importance of the fundamentals during the winter months the winter 2008/2009 has been studied separately.

Effekter av predationsrisk på sånglärkors (Alauda arvensis) habitatval på åkermark

Along with other European farmland birds, the skylark (Alauda arvensis) has declined rapidly since the 1970?s. Between 1975 and 2003, the Swedish population of skylarks declined with 64 %. In Britain, the decline is often explained by alterations in farming practices in general and the shift from spring-sown to winter-sown cereals in particular. The dense vegetation structure of winter cereals is limiting the number of breeding attempts possible, causing the entire population to decline.

Förstudie och utformning av grönrum och terrass, Tillbyggnad till äldreboende på Forellen i Partille

Partille municipality is planning an extension of the building Forellen. Green environments in health care have been shown to improve the health of patients, especially in elderly care. This report addresses the possibility of using the leftover space in close connection to a dementia and short-term accommodation to a winter garden and a terrace. The report also analyzes the impact of these green spaces on the residents.The purpose is to find alternative answers on the issue through the study of nursing homes and green spaces, and that these may be useful for Partille municipality and inspiration for future projects. The goal is to get conclusions in to a report, drawings, and an oral presentation.The results show that the design of environments can affect human well-being and also be healing both mentally and physically.

Bakteriell produktion i humösa istäckta sjöar i norra Sverige

The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.

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