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76 Uppsatser om Coarse aggregate - Sida 2 av 6
Rening av avloppsvatten efter skärprocess
ABB I-R Waterjet Systems combines the robotics and motion expertise of ABB
Flexible Automation with high-pressure intensifier/pumping technology from
Ingersoll-Rand to provide and continue to develop innovative waterjet cutting
systems for global markets.
The purpose of this assignment is to develop a process water purifier. The
purifier should be applicable as an option to ABB I-R?s production cell
Cutting-Box.
At first hand the process water should be purified well enough to let out in
the municipal sewage system, but the ultimate solution is purifying the process
water to the range that recycling is possible.
When investigating the different principle of purifying water, a research of
different products and their manufactories was done.
These different products were compared and the principle of filtration was the
most applicable, as most of the products were designed for far larger
applications.
As the process water contains quite large amount of particles, it is necessary
to perform the filtration in different steps.
The process water purifier is therefore composed of a module of coarse
filtration and one of micro filtration.
In the module of coarse filtration the mainly amount of fibres and particles
are eliminated. They are kept back in the container unit with the larger
fragments and dumped with these when the container is emptied.
In the module of micro filtration the filtration is performed in two steps.
In the first step particles larger than 50?m are eliminated, in the second step
the micro filter is setting the range of purifying, in this case 10?m.
Hur bemöts Kina i Afrika? : En mångdimensionell idealtypsanalys av Sydafrikas, Zambias och Zimbabwes bemötande av Kinas ökande ekonomiska intresse
The outset of this study is to contribute to the literature concerning China?s increasing economic interest to engage in the African context, its economies and resource abundandce. The overarching research problem is that the approaches held by the respective African state entities may facilitate increasing development gains for the recipient state of this economic interest in principle. To adress this research problem the study is undertaken by conducting a comparative case study where three cases/states, with presumably diverging economic and political status, are likely to effect their overall state approaches differently.Research questions, which are addressed by the creation of an idealtype analytic matrix, concern whether the states of South Africa, Zambia and Zimbabwe take on a more ?permissive? or ?restrictive? approach towards China?s economic interst and whether the approaches can be looked upon on both aggratege and case/area-specific levels.The main findings are that a clear tendency of the ?permissive approach? may be noted on a aggregate level for all cases.
Försök med olika såmaskiner vid konventionell sådd och direktsådd
In this thesis, two studies with different drills were included. In one of the studies two drills were compared: Väderstad Rapid and Väderstad Spirit. In the other study various drills for direct drilling were compared.
The study with Rapid and Spirit was placed in two locations with different autumn tillage; one on ploughed land in Uppsala and one on cultivated land in Västerås, both with relatively high clay content. Rapid drills have a single disc coulter, while the Spirit drills have a double disc coulter. Various aspects were compared such as aggregate distribution, seed placement, emergence, crop yield and economic outcome.
Bottensedimentets betydelse för flodpärlmusslans föryngring ? en metodutveckling
The freshwater pearl mussel Margaritifera margaritifera is an endangered species. To survive, the young mussels demand a fairly coarse bottom material containing an appropriate quantity of organic substrate to survive without suffocating. In order to estimate if a bottom is suitable for juvenile mussels, samples of the sediment are needed. To obtain samples a sampling device called the Mulv collector has been developed within this project. Bottom samples were collected from 18 stations in 4 south Swedish streams, Vramsån, Kling-storpsbäcken, Brönnestadsån and Bräkneån.
Glupförekomster i Uppsalaområdet
One special feature in the Swedish nature, mainly in the county of Uppland is one distinctive kind of dip, which can be distinguished from its fast and unaccounted drainage. These dips are called ?glupar? and can mainly be found in coarse-grained pebbled moraine under the highest shoreline (HK). During spring, and particularly when snowmelting occur, the wateramliptude fluctuates a lot until late summer or the beginning of fall comes; these dips are then often almost fully drained. During winter however, the waterlevel stands high.
Habitat preferences and reproductive success forthe threatened longhorn beetle Plagionotusdetritus
Plagionotus detritus is a threatend longhorn beetle that only exists at one site in Sweden. It is saproxylic and depending on recently dead coarse oak wood for its larval development. Trees at Djurgården, Stockholm that have been colonized by Plagionotus detritus has been studied to find out the habitat preferences of the species and to see what affects the density of beetles in a tree. The bark of some trees and wood from the breeding project at Nordens Ark has also been studied to find out what affects the species reproductive success. The reproductive success was measured in two ways, the larval mortality and the size of the hatching holes.
Online Brand Community in Action. A Constitutive netnography: Advancing a Wholesome Ethnomethodological Perspective on Brand Community
This thesis advances an explicit, consequent, and wholesome ethnomethodological perspective on brand community. It recognizes brand community as a social problem ? something to be continuously solved and achieved. The two main perceivably stable features of the Nikonian community are (1) practical usefulness and (2) the social link. The authors suggest that both features are constantly accomplished through three types of aggregate behaviour (1) lurking, (2) ordinary membership, and (3) community citizenship behaviour (CCB).
Påverkas miljökuznetskurvan olika av ekonomisk frihet än av demokrati
According to the theory of environmental Kuznets curve there is a relationship between carbon emissions and GDP. The relationship has an inverted U-shape. Carbon emissions rise initially and then decreases once a certain level of GDP is obtained.This essay interprets earlier studies in the field of environmental economics and uses public choice to seek answer on how the population acts on aggregate level. This essay analyses 115 countries in cross-sectional data. The analysis shows that there is a significant relationship between carbon dioxide emissions and GDP that is increasing at first and then decreases for a certain level of GDP.
Övergång till helkrossballast : En studie för Strängbetongfabrikerna i Veddige och Herrljunga
This exam report has been developed in association with Strangbetong AB, Sweden.The natural gravel that is being used as fine aggregate for concrete production today is an ending natural recourse and the Swedish government has decided to strongly reduce the extraction from the year of 2020. The only reasonable replacement is aggregates from crushed rocks but this material has other properties than natural aggregates. The concrete manufacturers now have to learn how to use these new fine aggregates in a cost effective way in order to ensure the quality of their concrete production.In this project, crushed aggregates and combination of crushed and natural aggregates have been tested with existing formulas for fresh concrete. The two parameters yield stress and plastic viscosity have been measured which gives a good description of the workability of the fresh concrete. Different methods to make measurements on the dry fine aggregates, has also been tested, to find out if there is any correlations between these parameters and the parameters from the measurement on the fresh concrete..
Majsensilage - partikelstorleksfördelning och hygienisk kvalité :
Fieldstudys on 22 farms (23 silos) to study relationships
between the actual particle size of the maize silage and the theoretical length of cut. The measure of theoretical length of cut were stated by the farmers and not measured by us.
Particle size of maize silage was determined using the New Penn State Forage Particle
Separator. SLU Skara made a special sieve for us, that had larger holes than de original
sieves. The samples were shaken after instructions and then the
material was weighted. We have also been taking out samples for microbiological
analyses from the silos on 13 of the farms.
Bottensubstratets inverkan på föryngring av Flodpärlmussla
The freshwater pearl mussel (Margaritifera margaritifera) is threatened throughout its range. There has been a substantial decline of the species and one major reason is habitat degradation. We investigated how the substrate composition of the bottom floor affects the regeneration of the mussel by analyzing data from the Västerbotten County Board?s inventory of the freshwater pearl mussel. The results implied that fine material such as fine sediment and sand might be detrimental to regeneration whereas gravel and boulders and in particular stone seem to be beneficial.
Den ociviliserade "norrlänningen" - en studie om social kategorisering och stereotyper
In this thesis we have tried to show the problems that the categorisation of ?norrlänningar? generates. We have also tried to describe what the stereotypes of ?norrlänningar? are by examining what people say on web logs. The method we have used to find the stereotypes in our empirical material is the discourse analyse.
Produktionsskillnader vid olika antal sortiment
This study is done together with Sydved AB in the summer of 2012. The purpose of the study is to analyse how different quantity of assortments influence the production for forwarders and harvesters with multiple tree handling aggregate in thinning, by different tree volumes. To make this analyse a time study was performed where three entrepreneurs work has been analysed. Beside the analyse, of different quantity of assortments, has also been analysed how the tree volume and a forest fuel assortment effect the production.
The result of this study shows that the quantities of assortments have a significant meaning for the production. The biggest differences are most distinct between one and three assortments in the smaller tree volumes where production goes down if the quantity of assortments increase.
Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs
Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation.
Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.
EU:s tjänstedirektiv - ursprungsprincipen eller destinationsprincipen?
The Vaxholm conflict was initiated when the Swedish Trade Union for Construction Workers shut down a construction site in order to prevent a Latvian construction company to build a school after the two parties had failed to agree upon a collective agreement in compliance with Swedish regulations. An emotional public debate followed that resulted in a discussion of the proposal for the Services Directive of the EU, based upon the country-of-origin principle. In this thesis we will analyze whether the country-of-origin principle or the country-of-destination principle is best suited to capture the gains-of-trade that the common market hoards and improve welfare within the EU. We conclude that the country-of-origin principle is the more apt of the two, though it leads to some short-run costs such as structural unemployment. But these will be more than outweighed by the gains in aggregate welfare for the EU in the long run..