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785 Uppsatser om Ground faults - Sida 1 av 53
Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna
The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.
Hur ökad fukthalt påverkar pannor
This report is a description of a developed educational simulator over rail vehicles and its components. The simulator is a hardware-based prototype over a door system on rail vehi- cles. System specialists and technicians will use the prototype. The Simulator should give the user a technical demonstration on how components work in a door system. The proto- type consists of motor, switch, relay and sensor.
Utbildningssimulator av funktioner i spa?rfordon : Ha?rdvarusimulator med felso?kning pa? do?rrsystem
This report is a description of a developed educational simulator over rail vehicles and its components. The simulator is a hardware-based prototype over a door system on rail vehi- cles. System specialists and technicians will use the prototype. The Simulator should give the user a technical demonstration on how components work in a door system. The proto- type consists of motor, switch, relay and sensor.
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..
Vibrationsproblem i närliggande konstruktioner i samband med markarbete
Ground work like blasting, piling and excavation has always had a great influence during the planning phase of a construction project since it can cause damages on adjacent buildings and have severe economic consequences. This thesis deals with how vibrations caused by ground work influence near-by buildings and what methods geotechnicians and construction entrepreneurs use to handle these risks.The purpose of this thesis is to explain risk management in relation to ground work. In order to achieve this I have used a qualitative method by interviewing a geotechnician and a ground work contractor who possess knowledge and experience useful to this thesis. The result shows that vibrations from ground work spread through the ground as seismic waves that cause displacements and packing in the ground visible in adjacent buildings as cracks and subsidence damages. Geotechnicians study ground work vibrations by means of ground investigations and experience from previous projects in order to produce a risk analysis that entrepreneurs can use to reduce damages.
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.
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.
Vakuumisolering ? Ekonomiskt försvarbart för småhus?
The number of people in the world and the urbanization increases. This leads to a bigger need of space for the built environment, space that soon doesn?t exist. A large portion of humanity?s energy disposal is used for heating of buildings.
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..
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.
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.
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.
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.