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4933 Uppsatser om Population model - Sida 14 av 329
Tillämpning av en markprofilmodell för hydrologiska beräkningar i avrinningsområdesskala
There is a great need to reduce nutrient leaching from arable land into lakes and oceans. By using several different types of models it has previously been possible to describe nutrient losses in a catchment area with a minimum unit of sub-catchment level. At present, it is instead desirable to model a smaller catchment with an opportunity to re-connect the results to the corresponding fields in the catchment. Such models already exist but they are not fully able to properly describe Swedish conditions and land characteristics in our region.With the approach of creating such a model, SLU has developed a project with this work as its first stage. The model is expected to be created under the working name SWE-model which stands for Soil Water Environment and is in this first stage supposed to apply the SOIL model in catchment scale. During the procedure to describe the first step in the process of developing such a model adapted to Swedish conditions and which works in the catchment scale with an area of about 10-30 km2, focus has been set on calculating the transport of water flow from different hydrological response units. Regardless of the processes occurring in the soil after the water has been added, it is assumed that all the water which flows from each simulated unit is drained.In the first step the hydrologic response units were identified based on land use and soil type in the study area. With the help of a script with functions that retrieve and transform data, certain units were chosen for simulation. The script was also created in this project. Finally, the model results were aggregated and summarized for each unique unit, for each sub-catchment, and also for the whole catchment.From the results it is possible to see similarities in the flow dynamics between modeled and measured data. The efficiency coefficient has been calculated to correspond to the mean of the measured values for the whole simulation period. With an automated calibration process the model should be able to perform better. The volume error gives an indication of overestimation from the model..
Jag får kommentarer, alltså är jag : En studie i bloggkommentarers betydelse och bloggskapande med skrivprocessen som utgångspunkt
In 2012 blogging reached an all time high in Sweden. Around 400,000 people made blog posts at least one time during this year. Blogs have publishing as a main purpose and can after publication be read by anyone with a computer, smartphone or tablet with an Internet connection. This makes the blogger open to response through comments that can be either constructive or destructive. No research has been made regarding blog comments and their effect on bloggers and their writing process.
Adaptiv temperaturreglering av bostadshus
The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.
Prediktion av bostadsrättspriser i Stockholms innerstad.
A frequently asked question in real estate marketing is at what time of the year it is optimal to invest or sell. The aim of the project was to answer this question and to generate a prediction model over real estate located in the centre of Stockholm that takes seasons into account. With acquired sales statistics in Stockholm between 2010 and 2013 it was possible to perform a linear least square regression, also known as Ordinary Least Square (OLS), with describing qualities and season of sale as parameters. Statistical problems such as Multicollinearity and Heteroskedasticity have been taken into account when deriving the model. The result was a highly accurate prediction model indicating the profitability of investing in real estate during the summer and selling during the autumn..
Kan man genom kartstudier förutse häckningsframgång för ängshök (Circus pygargus) i Uppland? :
Montagu´s harrier (Circus pygargus) is a diurnal, Eurasian raptor, which migrates from its northern breeding grounds to winter in sub-Saharan Africa. In Sweden, its core breeding area is centred on the island of Öland, with a stable breeding population of approximately 40 pairs. The province of Uppland is on the northern end the distribution range, where 4-8 pairs have regularly bred since the 1980s.
In Sweden, the Montagu?s harrier is classified as an endangered (EN) species. This classification is partly due to a lack of preferred nesting habitat, such as shrub-lands or dense wetlands with Claudium spp.
Produktivitet och kvalitet vid stickvägs- respektive beståndsgående förstagallring :
Nowadays the majority of the thinnings made in Swedish forests are done by machines, harvesters and forwarders. The most common model in thinning with a harvester is strip-road operated thinning and stand-operated thinning with one intermediate passage between the strip-roads. This study is a time study with some quality follow ups on a strip-road operated thinning model, a stand-operated thinning model with one intermediate passage between the strip-roads and a stand-operated thinning model with two intermediate passages between the strip-roads. The machines in the study were a small harvester (Forestline MPM C90) and a medium sized forwarder (Timberjack 1110).
The study was made in Litsnäset outside the city of Östersund in Sweden and was made during the autumn 2007. In a lodgepole pine stand six study units (0,6 ha) were thinned with the three different models, two study units per model.
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.
SIDAs Watergate : En ide?historisk undersö?kning av debatten om svenskt bistånd till det indiska befolkningsprojektet 1977?1980
In 1975 the Indian president Indira Gandhi proclaimed the emergency period which would go on until 1977. Under this time approximately 8 million men and women were sterilized in the name of family planning. Many of them did not volunteer. This was not just an Indian con- cern because the family planning program was largely funded by international aid. The Swe- dish involvement in the program was debated 1977?1980, in what has been called ?SIDA?s Watergate?.
The importance of relationship for self-care capacity among young people with diabetes mellitus type 1 : Based on external factors in Orems model of self-care.
In Sweden approximately a half per cent of the population have diabetes mellitus type 1. Self-care responsibility is a part of the treatment. Orem?s self-care theory has been used as theoretical framework. The purpose was to describe what it means to be young and have diabetes mellitus type 1.
Assessing attachment models using the implicit association test
Internal working models of attachment are claimed to be unconscious structures operating outside the conscious awareness. Existing measures of attachment are almost exclusively explicit, either self-reports or interviews and it is questionable whether these instruments are able to tap into unconscious attachment attitudes. The main purpose of the present study is to develop Implicit Association Test (IAT) tools for assessing adult attachment and to examine their construct validity. Two sets of implicit attachment measures, based on the two-dimensional attachment model (Bartholomew & Horowitz, 1991), were developed. Convergent validity was assessed by examining (1) the relationship between implicit model of self and implicit self-esteem and (2) the relationship between the implicit model of other and implicit sociability.
Integration av simuleringsmodeller för bränslesystemet i JAS 39 Gripen
In this final thesis two simulation models have been integrated. The simulation models are models of JAS 39 Gripen?s fuel system, software and hardware. The time consuming and costly work to develop software has made the department of fuel system to build two models in Xmath/Systembuild. The software model also simplifies the comprehension of how the software in the control computer of the fuel system works.
Är BIM lönsamt vid projektering av ett småhus?
This report brings up the question - ?Is BIM profitable when planning a single-family home??.The methodology for finding the answer to this question is firstly to state the definitions of BIMand the company that is projecting by using the BIM-model. The answer is then obtained byanalyses of the factors of profitability with respect to: time, opportunity of revision, problemvisualization, preference adjustments and energy. A BIM-model has been made simultaneously asthe writing has proceeded to get a perception of how a BIM-model really matters for the analysis.The analysis shows that the answer for the question depends on further factors. The factors thatare mostly discussed are the company?s intentions and the complexity of the house.
Beräkning av ASME-flänsar enligt EN-standard
In this thesis, a transparent model of the human head has been constructed which was filled with a substance that represented the brain. This model was later crash tested. This was done in order to examine how a transparent model of the human head can be constructed to generate accurate data from crash tests. It was also done in order to examine how impacts on the front of the head can deform the rear of the brain. When a head is decelerating, the brain moves forward inside the skull and may hit the front of the skull.
En andra chans ? en överblick av secondhandkläders marknad
In our globalized society massconsumption is widespread. However there is a trend showingthat people are starting to re-use clothes instead of buying newly produced garments. Reasonsfor buying secondhand clothing are many. During the 1950s people strived to look likeeveryone else but in the 1960s this changed. Subcultures grew stronger.
Styrning mot förändring: En fallstudie rörande organisatorisk förändring i offentlig sektor
This paper examines and analyzes effects of the introduction of a new management control system tool within a Swedish public health organization, the Södra Älvsborg hospital, and its possible effect on organizational change. The new management control system tool, known as the SÄS-model, has been widely criticized for being too costly and with too small positive effects to be shown. Our approach has with that as a background been to examine whether the implementation of the SÄS-model and its balanced scorecard has been able to result in effects regarding organizational change. We have through a case study aimed to analyze how a management control system, much alike one that is typically used within foremost private organizations, can promote organizational change. Our results suggest that the implementation of the SÄS-model and the balanced scorecard has given the organization clearer visions and goals.