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4722 Uppsatser om Transport model - Sida 5 av 315

Transport av volymelement : Förutsättningar ur ett företags perspektiv

Building with volume element is relatively new and has started to increase more and more. The regulations that exist to regulate and determine how the transports of volume elements are to be conducted are diffuse and not very well adjusted to address the issues with transporting volume elements. Today there are a number of instances that a company has to turn to in order to get a somewhat different view, what regulations say and interpret it in order to know what applies and not applies regarding the transportation of volume elements. regulations. The rules that are in place make it tough for the volume element producing companies to develop and continue to be active on the market.

Demonstrationsprojektets roll i framväxten av ny teknik: Fallstudier av två vindkraftprojekt

This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.

Modellering av en panna med rörlig rost :  

The aim of this master thesis was to create a dynamic model for the processes in a solid fuel boiler of the moving grate type. Another aim with the model was to keep it as simple as possible but still able to catch the dynamics of the processes in the bedplate of the boiler. The creation of the model had its origin from drying and combustion equations used in earlier modeling work of boilers. The represented model has been used to simulate different kinds of disturbances in a boiler and different ways to control the boiler. These tests show that controlling a number of parameters in the bed of the boiler is an effective way to keep the grate stable during disturbances.

Färdvägsmiljöer vid cykling för transport : En studie av en modell om uppfattningar av färdvägsmiljön hos cyklister

SummaryAimThe study examines a theoretical model developed to capture cyclist´s perceptions of the route environment. The survey focuses on if level two and three in the theoretical model captures what it´s intended to do. More specific we ask ourselves how the three appraisals (unsafe/safe by traffic reasons, stimulating/inhibiting route environment, unsafe/safe by other reasons) in the model´s second level relates among themselves and if these three appraisals can capture the degree of environmental well-being/unwell-being in the model´s third level. The questions were: Do the three appraisals differ among themselves? What is the difference/-s in such cases? And, is there a correlation between any of the three appraisals and environmental unwell-being/well-being? What is the correlation in such case? MethodThe gathering of data was done through questionnaires.

Dynamisk massbalansmodellering av fosfor i Östersjön

During the past few years a vast amount of research has been done to increase the understanding of the complex ecosystem of the Baltic Sea. Modelling and simulations are important tools to increase knowledge of the system. A suitable model must be simple to use and the parameters and variables needed in the model must be easy to access.In this paper a dynamical mass-balance model, CoastMab, which is validated for smaller coastal areas, has been used to predict concentrations and transports of phosphorus in three large coastal areas - the Gulf of Finland, the Gulf of Gdansk and the Gulf of Riga. CoastMab uses ordinary differential equations to regulate inflow, outflow and internal flows. To reflect seasonal variations in temperature and different types of flows the model has a temporal resolution of a month.

Competition for forest fuels in Sweden : exploring the possibilities of modeling forest fuel markets in a regional partial equilibrium framework

This thesis project focuses on the need for better tools for analyzing competition for forest fuels in Sweden, in particular how policy measures may influence the market and involved actors in different regions of Sweden. Raw materials from the forest have for long constituted important inputs in the Swedish forest industry. Today some of these raw materials are increasingly used as inputs also in bioenergy production, largely driven by bioenergy promoting policies, and there are signs of increased competition for forest fuels which may have various and uncertain effects on the industries in question. The thesis project explores the possibilities to adapt previously used forest sector equilibrium models into a new model suitable for analysis of Swedish forest fuel markets, called the Swedish Forest Sector Trade Model (SFSTM). The approach takes into account regional differences in supply and demand for 23 types of products produced and/or used by eight types of producers, plus consumers, in five different regions (four Swedish and one international).

TOMO Hugglink

Tomo Hugglink (TOMO Skog) is an innovation for harvest and transport of biofuels. The system consists of a truck, a chipping unit and crane mounted on a link and a wood chip trailer. The system works in such a way that the chipping unit is disconnected and placed on the site and wood chips are loaded directly into the wood chip trailer.The aim of this study was:- To examine the performance of the TOMO Hugglink system under different conditions such as the size, placement and quality of the pile.- To calculate the cost per raw ton for two vehicle combinations at different transport distances and to examine the effect of a reduction in set-up time and an increase in load weight.- To identify possible improvements with the TOMO Hugglink system.A time study was conducted within the thesis work to make it possible to determine production and time consumption. In the subsequent economic analysis the cost per tone at different transport distances was calculated for two different lorry concepts. Furthermore the effect of a reduction in set-up time and an increase in load weight was calculated.Under current conditions the utilization of the chipper is low and only 29 % of the total system time is occupied by chipping.

Transportbranschen : Miljöanpassning utan negativa företagsekonomiska konsekvenser, är det möjligt?

This paper is about how transport companies in the future will be able to adapt their activity to an environmentally sustainable development without the effect of negative company economic consequences. Today, the environmental threat is a global problem and knowledge about that effluent of carbon dioxide have a negative impact on the climate is generally known. A transport system that works well is important for Sweden, but the sector has a negative impact on the environment. Regulation and legislation for increased environmental requirements often meets resistance and fear that the work will be hampered by increased costs for environmental work that can lead to an international decrease in competitiveness. The transport companies have outside pressure from the society to do something about the environmental issue, however the companies? customers are not ready to pay a higher price for environmental work.

Slitage på skogsbilvägar vid virkestransporter

This report discusses questions concerning wear on forest roads. The purpose of the work is to investigate if the wear on the roads will decrease when the speed limit gets lower for the trucks that transport the wood. A normal forest road, class B, was used in the study. In total 5000 m3f timber was transported on the road. Data about the road was measured with a profilograph car before and after the timber transport.

En studie av sedimenttransport, död ved och kantzoner längs två vattendrag i Kilsbergen - från skog till slätt :

Headwater streams are affected by anthropogenic impacts at multiple scales. One aspect of human impact is sediment transport associated to the abundance of stream structures as large woody debris and the composition of the riparian zone from forest to agricultural landscapes. Riparian buffer zones and stream structures like dead wood are considered as generally important structures for protection against an increasing amount of sediment particles in the water. Hence, in this study these structures were quantified in thirty different stream segments on land and in the water. To measure the transport of sediment Whitlock-Vibert boxes were used in three different types of landscapes; forest, transition and fields. The boxes were left in the stream segments for three months, the taken up and dried and weighed. The results showed that the transition-land in Frösvidalsån had the highest sediment transport. The second highest transport of sediment was in Blackstaån at the fields.

Djurvänlig hantering av lantbrukets djur i samband med transport

Handling, loading, transport time and unloading in connection to transport of farm animals affect animal welfare. Induced effects include both psychological and physiological stress responses in animals. The physiological parameters may be measured through blood analysis while behavioural changes often manifest themselves through increased vocalisation, escape attempts and apathy. Physiological parameters are additional parameters of importance when measuring animal stress responses. The handlers behavior during transport has been shown to have major impact on animal welfare and the quality of meat. Animal friendly handling and driving of animals create a more manageable work environment for the handlers. To further increase animal welfare in connection to transport, stables should be built with well adapted drift passage and ramps on the transport vehicle.

Modell av en synkronmaskin för PSCAD/EMTDC med magnetisk mättning i d-led och elektriskt gränssnitt för fältmatare

This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.

Analys, modellering och återskapande av fordonsdynamiska rörelser i tåg

The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform.

Två nya trailerkoncept för transport av rundvirke hos Stora Enso : en analys av prestation och flexibilitet

The need for roundwood transport capacity vary throughout the year. The need during a period is influenced mainly by the volume transported the period, the number of days during which transport can be carried out, seasonal variations in road conditions and the weight of the roundwood, and the origin of the wood (private forest owners/ forest companies). The need for transport capacity generally increase during the winter and in spring, after thawing. Lack of logging trucks combined with a lack of drivers for these trucks make it hard to hire extra help during periods of increased transport capacity needs. It is also very expensive to keep logging trucks for use only during these periods. In this thesis, two new concepts based on the partial transport by truck tractors have been examined, to find out the possibility for increased performance and flexibility.

?Vad är det jag gör egentligen?? - om att med videons hjälp bli medveten om helheten

This project consists of an adaptation, trial and evaluation of a model for practicing. Based on prior research I created a model aiming mainly to raise a musician?s self- awareness around the different parameters a performance consists of. An additional wish was for it to simultaneously assist the musician in monitoring his or her progress. With video recording and self-evaluation as the two main parts I tried the model by using it over a period of three months.

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