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745 Uppsatser om Ground fault - Sida 6 av 50
ini
Preporsition for bachelor thesis project, working from the inside and out. Emphasising spatial quality and experience, More or less ignoring form and program. I?ve had issues with these aspects in earlier project, the form or the program takes alot of place in the project. I haven?t tried this approach before, it?s an attractive thought to allow the project take a form of it?s own, enclosing those spaces i create.The initial concept was to place the pools on the ground (not digging them into the ground) making them volumes that divide and define spaces.
Trädföryngring i låga gropar uppkomna vid brand i boreal naturskog :
This study was conducted in the "Kåtaberget" forest reserve in Västerbotten in the summer of 1999. In the summer of 1995, a prescribed burning was performed in the reserve. In some places where coarse dry woody debris (logs and stumps) was present, the fire consumed the wood, as well as parts of the humus layer, creating deep-burned patches. The low intensity ground fire also created dead woody debris by burning off living trees with open fire scars, as well as standing dead trees.
In this study, the post-fire tree seedling establishment was examined, with special attention given to the former presence of woody debris. The study also includes a survey of the areal extent of deep-burned patches, as well as an examination of tree seedling establishment in these patches, compared to other burnt ground.
De ska föregå med gott exempel! : En undersökning om elevers syn på lärares förhållningssätt till ordningsfrågor - disciplin, regler och konsekvenshantering
There are very few studies that have taken the matter of teacher?s leadership in disciplinary actions into research. That is why the purpose of this essay has been to investigate the relationship of how students think their teachers appear in questions of discipline. The study has been narrowed down to gather and analyze the experiences that students have about teachers, and how teachers uphold and set themselves to ground rules in the classroom. The study has shown how the students interpret teacher?s act of following up consequences of classroom rules.
Utvärdering av produktionsrapporterad volym för contorta
The background to this study is that the forest company, Holmen, has found large discrepancies between harvested volume and the measured volume at the industry. Factors like bark features, breakage, double tops, bends and stem damages was noted, and all stems were measured manually. Hypothesis testing with the method "random in pairs" were used to examine whether the harvester measured values significantly differed from the manually measured.
The result of a properly calibrated harvester shows in average underestimation of the volume with Skogforsk Pine as a bark function. This means that the harvester isn´t the reason why the volume measured in the industry is lower, the fault is elsewhere. The study also indicates a need for a unique bark function for logepole pine..
Metod för användning av Geografiska Informations System vid långsiktig vägplanering : en studie genomförd på Sveaskogs marker i Norrbotten
The forest industry is one of the most important industry branches in Sweden. Since the demand of high precision wood deliveries has increased, the demand on a well constructed forest road net also has increased. A good road net gives the wood-supplier competition advantages and also increases its service level towards its customers, lumber-mills and pulp-mills. In some parts of Norrbotten, the road net is still insufficient and not yet built out enough, and that is why it is important to know how to act and where to improve the road net in these areas.
The purpose of this thesis was to create a work-model for long term road planning in areas with no road net or a not yet complete road net. The model has been created in an ArcGis environment, where a long chain of tools has been tied together with the program ?Model builder?.
Termisk analys av kompakta jordvärmesystem - Sensitivitetsanalys och korrektions faktorer baserat på fältmätningar i referensanläggningar i Östergötland
Chapter 1 defines the aim of the project and gives a general orientation about ground heat extractors. In chapter 2 physical processes that could be expected to be involved in the heat transport around a ground heat exchanger are discussed. It is shown from a literature study what amount of moisture transport due to thermal gradients there could be expected in a ground heat exchanger. The conclusion is drawn that the moisture gradient (Sr) is of same magnitude as the driving temperature gradient (°C). At the expected amount of increased moisture around the pipes the moisture transport could be considered to have a little effect on the brine temperature.
Vinkelfelet i mätkretsens påverkan på riktade jordfelsskydd
Utfört examensarbete undersöker vinkelfelet i mätkretsen för riktade jordfelsskydd och hur det påverkar dess felbortkoppling. Uppkomna vinkelfel i mätkretsen kan påverka det riktade jordfelsskyddet så att verklig felström och uppmätt felström inte stämmer överens, vilket kan leda till uteblivna eller obefogade felbortkopplingar. Vattenfall ställer krav på att vinkelfelet får uppgå till max ±2 grader för mätkretsen. Eftersom vinkelfelet i många fall har en hög påverkan på jordfelsskyddets noggrannhet undersöks vad Vattenfalls vinkelkrav egentligen innebär. Största orsaken till vinkelfelet uppstår oftast i strömtransformatorn och därför undersöks hur mycket två strömtransformatorer med olika klassificeringar som är vanliga i elnätet påverkar vinkelfelet i mätkretsen.Jordfel är det vanligast uppkomna felet i mellanspänningsnät och dess storlek beror till stor del på hur mycket kapacitivt bidrag som finns på linjerna samt värdet på nollpunktsresistorn.
Öppen dagvattenhantering i urbana miljöer :
Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.
?Bokpallar i en stormarknad? eller ?Biblioteket i Babel?- vart är vi på väg? En diskursanalytisk studie av privatiseringsdebatten hösten 2010-våren 2011
The subject of this bachelor thesis is the debate regarding privatization of public libraries. The purpose is to investigate howprivatization is portrayed in different articles and by different participants. The articles used are from two of Sweden?s largest national daily papers: Dagens Nyheter and Svenska Dagbladet and two of Sweden?s largest library magazines: Biblioteksbladet and Tidskriften BiS: Bibliotek i Samhälle. The questions asked are: how is privatization portrayed? Whatdiscourses can be traced in the texts? And: can one foresee a future aiming towards privatization? In order to answer these questions Norman Fairclough?s critical discourse analysis was used as atheoretical and methodological viewpoint.The discourses found were named: The value ground discourse, the market liberal discourse and the pragmatic discourse.
Planering av produktionsflöden. Vad kan påverkas i projekteringsfasen?
Göteborg Energi AB är ett bolag med höga ambitioner att säkerställa ett stabilt distributionsnät för sina kunder. Med ett säkerställande följer åtgärder i form av beräkningar för komponenter som transformatorer av olika märkeffekt, hög- och lågspänningssäkringar och andra kritiska skyddsanordningar som t.ex. reläskydd. Vid ett flertal tillfällen under de senaste åren har det uppmärksammats en problematik där ett fel i lågspänningsnätet har löst ut anslutande transformator. Felet har grundat sig en svag selektivitet mellan transformatorsäkring och lågspänningssäkring.
3-D handlingar, GPS-styrning och VA-moduler- En ny metod för framtida anläggningsprojekt
Ground construction has to a large extent been dominated by traditional meth-ods during the last 50 years. Although the construction has been changed meanwhile innovations are not accepted. In collaboration with NCC Ltd Region South, I have examined a modern con-struction methodology that has been developed by NCC for future large pro-jects. The method is divided into two central phases. Phase 1 is? Single Pro-duction? which is a preliminary period for ground constructions to come.
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.
Selektivitet mellan hög- och lågspänningssäkringar ? I anläggningar med transformatorer ? 500 kVA
Göteborg Energi AB är ett bolag med höga ambitioner att säkerställa ett stabilt distributionsnät för sina kunder. Med ett säkerställande följer åtgärder i form av beräkningar för komponenter som transformatorer av olika märkeffekt, hög- och lågspänningssäkringar och andra kritiska skyddsanordningar som t.ex. reläskydd. Vid ett flertal tillfällen under de senaste åren har det uppmärksammats en problematik där ett fel i lågspänningsnätet har löst ut anslutande transformator. Felet har grundat sig en svag selektivitet mellan transformatorsäkring och lågspänningssäkring.
Perenner i Norrbotten - Ja, varför inte? :
In this thesis, I have discussed which (herbacious) perennials that are sold most in
the county of Norrbotten in the upper north of Sweden. Also discussed are the factors
considering overwintering and factors that affect the chances of survival. The reason
to the subject is that I m born and raised in Norrbotten and throughout the years I ve
wondered why so many of the perennial flowerbeds look so similar. The purpose of
the thesis is to give another approach to the composition of the garden by explaining
some of the factors that controls the survival of plants. The information is gathered
partly through interviews with plantshop personnel and partly by a literature study.
The results of the interviews reveal that tradition and hardiness is the major reasons
to the consumer s choice.
Riskbedömning vid Saltvikens kopparverk
AbstractAt Saltvikens copperindustry, which is located in the municipality of Oskarshamn, copper was refined from sulphiteore some hundred years ago. The ore underwent several steps in the process before the final product was received. These steps all had an influence on the environment through discharge of heavy metals. The area where the copper industry was located is today considered to be of specific national interest due to its valuable nature and cultural values, as well as its value for recreational outdoor activities. Therefore, it is important to determine the present level of contamination and if any transport of contaminants have occurred, and to identify the risks that are associated with the site both at present and in a longer time perspective.Thirtynine soil samples and 16 sediment samples have been analyzed.