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745 Uppsatser om Ground fault - Sida 2 av 50
Rhododendron och dess skadegörare
Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.
Reducering av markskador vid GROT-skotning
Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.
Feldiagnos för RM12 baserad på identifierade modeller
The jetengines of today are growing in complexity. Reliability for aircraft engines are of extreme importance, mainly due to safety reasons but also economical ones. This master thesis deals with faultdiagnosis in the turbine section of RM12, the engine used in Saab/BAe's Gripen. Three different faults which can occur in the turbine section was studied. These faults are: clogged fuel nozzle, hole in outlet guide vane and sensor fault.
Hur skapar man en funktionell och beständig dörrmiljö? : En närmare studie av ståldörrar
Today?s construction buildings contain more advanced technologies than before. The development of newer and stricter regulations to the construction industry makes the door environment more and more complex.In large construction projects the door environment is held up as a major challenge to get to in a good way. It turned out after a discussion with one project manager and a site manager at NCC, that the door environment is difficult to get right in major construction projects and it often causes many error reports in to the aftermarket after that the final inspection is completed.Interviews have been done with key figures in the building process at NCC and Akademiska hus. A study on a university building for around 3500 students and with 300 workplaces was made.
Luftvärnets verkanssystem i Utlandstjänst
This paper aims to analyze if ground based air defence of the Swedish Defence Forces is sufficiently equipped to protect units serving abroad. The Swedish ground based airdefece has its roots in the era of the cold war but the focus of Swedish Defence Forces has shifted from defending Swedish territory to peace keeping and peace enforcement in foreign countries. First I will take a look at the base factors for ground based air defence units serving in a peace keeping or enforcing mission and then use this to define what abilities you would like to have in a ground based air defence system. Finally I will compare these abilities whit the abilities of the ground based air defence systems that are in use whit the Swedish Defence Forces.My conclusion is that the question can´t be answered on a generel level but every mission has to be analyzed individualy.The author of this paper is Cadet Tobias Jönsson studying at the The Armed Forces Technical School to become an officer in the Swedish Defence Forces..
RCC-Jordfelsskydd, mätmodul för övertonsanalys
The majority of all power cuts that affects individuals and communities are caused by earth faults on the power transmission lines at 10kV and 20kV level [1]. If these power cuts could be eliminated, less disturbances and interrupts would lead to large amounts of money savings.Swedish Neutral has developed such a protection system. When an earth fault occurs power is injected into the neutral point of the transformer. The RCC (Residual Current Compensation) protection calculates a compensation current exactly 180 degrees out of phase to the fault current. Doing this, the voltage at the fault location becomes very close to zero, without affecting the power transmission.The protection system can only compensate automatically for the fundamental frequency (50Hz), and manually for the 3rd, 5th, 7th and 9th harmonics.
Identifiering av parametrar för tillståndsbedömning av en vattenkraftstation
The report begins with a general inventory of possible technical faults in a hydropower plant and of possible fault indicating measurements. Then an investigation is made concerning a few different faults. Based on this investigation a choice on seal box condition and water leakage is made as problem for a more thorough examination, in which it is concluded that the turbine water leakage is larger when the turbine is put into operation. The examination ultimately results in a computer alarm for faults related to the seal box. Finally a few things are mentioned about flow measurement and pressure measurement in relation to the project as a whole..
SAME GROUND : musik från min sanna grund
Mitt arbete handlar om redan från de att jag startade mitt eget band Ridge fram tills dess att vi släppte vår debutskiva Same Ground. Om att våga göra musik från sitt hjärta,att tveka,kämpa,repa,spela in och att släppa skiva på eget bolag. Det handlar också om min uppväxt och hur det påverkat mig. Jag skriver reflekterande om processen..
Saltvattenpåverkan i enskilda brunnar i kustnära områden : En undersökning av grundvattenförhållandena och riskerna för saltvattenpåverkan i S:t Annas skärgård, Östergötland
Coastal areas are popular for housing, both for permanent living and holiday houses. At the same time, thin sediments and small storage capacity in the bedrock makes the ground water resources limited. The limited ground water resources combined with too large withdrawals of ground water makes salt water intrusion a problem in many coastal areas. This study examine the risk of salt water intrusion in drinking water supplying wells on the island Södra Finnö in S:t Anna archipelago, Östergötland, Sweden. A calculation of the relation between ground water recharge and withdrawal is obtained to analyze the ground water balance in the area.
Nollföljdsmodellering av transformator-Beräkningar av följdproblem vid ökad kablifiering på mellanspänningsnivå
Historically transformers with system earth equipment have been modeled as open circuits in zero sequence. This approximation has been satisfying, but lately it has been discovered that equipment on one side of the transformer have responded to faults that occurred at the other side. Most of these problems took place when the majority of the system on the secondary side of the transformer contained cables. These findings have led to questioning whether or not the former model of the transformer in zero sequence is correct. This report investigates if it is necessary to represent the transformer in zero sequence in another way than it is usually done today.
Frost hardiness of grapevine cultivars as affected by ground cover under Scandinavian conditions
Cultivation of grapevine is novel under Scandinavian conditions. We studied the impact of ground cover on frost hardiness of grapevine cultivars in Northwestern Scania in a two-factorial trial with four cultivars Solaris, Pinot Gris, Siegerrebe, Ortega and three kinds of ground cover (open soil, plastic cover and gravel). The study was conducted in a grapevine orchard, planted in May 2009, in Broddarp on Bjärepenisula Sweden (N latitude 56°; longitude E 12°). Soil and air temperature were monitored continuously.
Frost hardiness measurements were performed every second week from late September to early December 2009. Frost resistance, LT50, was determined by electrolyte leakage measurement of the upper stems after artificial freezing at -15 °C.
Stereotypa förklädnader? : En tematisk läsning av John Greens The Fault in Our Stars
Syftet med min kandidatuppsats är att undersöka hur föreställningar om kön kommer till uttryck i barnlitteratur och på vilka sätt barnböckerna förhåller sig till traditionella normer och värderingar gällande kön och könsroller.Med utgångspunkt i fem populära barnböcker undersöks följande frågeställningar:Vilka roller tar personerna i boken och hur förhåller sig dessa roller till traditionella föreställningar om vad som är kvinnligt respektive manligt?Vad gör personerna i boken som kan tolkas som stereotypt respektive normbrytande?Vilka identiteter har personerna i boken, hur ser de ut, vad har de för kläder, leksaker och färger runt sig?Avslutningsvis kommer jag också att jämföra barnböckerna och diskutera likheter, skillnader, övergripande mönster, samt diskutera möjliga förklaringar till varför det ser ut som det gör..
Quartzene i gips : Densitet och hållfasthet
A substation must be properly protected against lightning and other external effects to the equipment in the station or staff, for that we use relay protection. They should also protect against internal errors which may occur as Ground faults. There are different types of protection relays, but most common are overcurrent-, distance-, residual current- and differential protection.The purpose of this thesis was to deepen our knowledge of relay protection and to use the theoretical knowledge we got from the university studies in the work process. In the process we discovered which parameters were the most essential and calculated these for all relay protections on the substation. We also carry out a comparison between two brands of relay protection, ABB and Alstom.During our work we will test and simulate the over-current relays in a program called NEPLAN, the program will also calculate the fault currents.
Framtagning av reläskyddsinställningar för en transformatorstation
A substation must be properly protected against lightning and other external effects to the equipment in the station or staff, for that we use relay protection. They should also protect against internal errors which may occur as Ground faults. There are different types of protection relays, but most common are overcurrent-, distance-, residual current- and differential protection.The purpose of this thesis was to deepen our knowledge of relay protection and to use the theoretical knowledge we got from the university studies in the work process. In the process we discovered which parameters were the most essential and calculated these for all relay protections on the substation. We also carry out a comparison between two brands of relay protection, ABB and Alstom.During our work we will test and simulate the over-current relays in a program called NEPLAN, the program will also calculate the fault currents.
Höga hus med deformerbara fundament på pålar : Pålkrafters avvikelse visavi klassisk teori samt förskjutningar beroende av vindlast
When forces in foundation piles are calculated according to classic theory, thefoundation are assumed to be infinitely rigid which means that the foundation will notbend. High buildings need their whole width to be stable and use the ground floorwall as a foundation. But when, for example windows are needed in the ground floorwall, the stiffness of the foundation decreases which change the forces in the piles. Inthis report the difference of pile forces versus classic theory has been analyzed, and ifpile forces can be calculated as in classic theory. Further on, the effects of the wallmovement were analysed and how the buildings crack safety would be affected by themovement at the ground floor.