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233 Uppsatser om Circumference of the earth - Sida 3 av 16
Analys av fördelningssystem för bostadshus
The purpose of this project is to analyze earthing systems for houses. By practical measurements and theoretical analyzes consequences of possible faults, that can occur within the facility and in the low-voltage distribution network, is illustrated. The reason for this project is that nowadays one has to arrange with a main equipotential bonding system for buildings. Apart from that, if necessary, bathrooms must be provided with a supplementary equipotential bonding system.The practical measurements verify that potential differences in facilities may be due to voltage drops in the PEN conductor between the origin of the electrical installation and the power transformer.Based on the theoretical analyzes of possible faults, it is considered that the requirement for supplementary equipotential bonding systems for bathrooms in most cases can be questioned, when basic insulation, fault protection, residual current devise and main equipotential bonding system already provides an adequate level of protection.A PEN conductor loss may result in a situation where metallic parts attached to the equipotential bonding system starts working as earth electrodes. Equipotential bonding system may also increase the incidence of stray currents. If TN-C-S systems is provided with a local connection to earth a redundant system against PEN conductor loss is obtained.
Temperaturzoner för lagring av värmeenergi i cirkulärt borrhålsfält
The thermal response of a borehole field is often described by non?dimensional response factors called gfunctions.The g?function was firstly generated as a numerical solution based on SBM (Superposition BoreholeModel). An analytical approach, the FLS (Finite Line Source), is also accepted for generating the g?function. In thiswork the potential to numerically produce g?functions is studied for circular borehole fields using the commercialsoftware COMSOL.
Människan i naturen : om etiska gränsdragningar och djupekologins kritik av antropocentriska naturuppfattningar
The subject-matter of the following essay is to investigate the relationship between what is commonly called Deep Ecology or Biocentric Philosophy, as articulated by the co-founder of the Deep Ecology Movement, Arne Naess, and later proponents of the biocentric school of environmentalist thought. I contrast Naess? concept of Self-realization as founded in his Ecosophy T to the ideas of american conservationist and co-founder of the radical green movement Earth First! Dave Foreman, and to the controversial finnish environmentalist and ecofascist Pentti Linkola?s ideological agenda of population-reduction respectively.According to some critics of the movement, especially the social ecologist Murray Bookchin and French liberal philosopher Luc Ferry, the Deep Ecology ideology is essentially misanthropic and totalitarian in structure. A central idea among deep ecologists is that ecosystems and natural entities have intrinsic value in themselves, even outside a human social context. This idea is thought of among deep ecologists to create a philosophically sound basis for counteracting the environmental global crisis.
Barns tolkning av en modell för vattnets kretslopp : -förståelse och tillämpning
AbstractThe purpose of this study is to find out how pupils give expression of a water cycle model and if the model causes any misunderstanding. Two problems constitute the starting point for this investigation. The first question is: how do the pupils explain the water cycle with the help of the jar model (can of glass). The other question is: can the children see any similarities between the can of glass and our earth. Qualitative semi structured interviews with seven pupils in the ages of 8-9 have been used to show the pupils? own thoughts and how they express them.
Google Earth och Street View : En säkerhetsrisk för svenska företag och myndigheter?
På senare år har etableringen av 3D-applikationer på internet, för att visualisera geografiska områden och platser blivit allt vanligare. Exempel på sådana applikationer är tjänsterna Google Earth och Street View, som levereras av företaget Google. Den snabba utvecklingen av 3D-tjänsterna har medfört bättre bildupplösning och mer detaljerade satellitbilder. Detta har i sin tur fört med sig att integritets- och säkerhetsrelaterade frågeställningar relaterade till 3D-applikationerna har aktualiserats. Från flera håll i världen har Google stött på ifrågasättanden och protester.
Tillväxthastighet och storleksfördelning hos hassel (Corylus avellana)
To increase the knowledge about the growth of hazel (Corylus avellana)and size distribution of the shoots, circumference and stem diameter wasmeasured in a total of 54 clones in two areas in Östergötland. Further, thewidth of growth rings was determined for separate years. The diameter ofthe stems was measured both out from the centre of the stem andperpendicular to the first measure. The stems showed only a weaktendency to have an oval shape (with the longest side outwards from thecentre). The growth model did not improve when the degree of sunlightof clones was taken into the account.
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.
Höghöjdsflygning & strukturella batterier : En konceptstudie i flygteknik
This report is written in the purpose to investigate the mechanical forces and characteristics related to a propeller driven aircraft in the Earth?s atmosphere. It?s written as a thesis project during the spring semester of 2014 and graded accordingly.Thanks Arne Karlsson for fruitful discussions. Also thanks to Simon Leijonmarck for help with useful discussions concerning structural batteries..
Populationsstruktur och genetisk analys av exteriöra egenskaper hos svensk ardenner :
The purposes of this study were to estimate genetic and phenotypic parameters for conformation traits in Swedish Ardenner, a heavy draught horse, and to investigate the inbreeding status of the population. Additionally, a breeding scheme proposal was created, based on the results achieved in the study.
The data studied were obtained from the Swedish Horse Board and from the Swedish Ardenner Association. The data included 1632 three-year-old horses, mainly mares, and 356 stallions, judged between 1986 and 2005 at conformation shows. The traits studied were type, head-neck-body, legs, walk and trot at hand, total score and height at withers.
Konsumtionens klimatpåverkan : En jämförande studie mellan två socioekonomiskt skilda bostadsområden, Araby och Söder i Växjö
The world is in a stage of climate crisis where the average temperature is rising, with consequences such as, melting ice sheets, increasing sea levels, and floods. The climate panel of the UN, IPCC, has stated that this is a reaction of anthropogenic emissions of greenhouse gases. The most important gas is carbon dioxide, which contributes with 80 per cent to the on going climate crisis.The increasing emissions of carbon dioxide are connected to human consumption patterns. This puts pressure on the earth, as humans demand more and more resources. Today the earth needs one and a half year to regenerate the resources humans? demand of it, by the year 2030 we will need two planets in order to cope with this increasing demand of resources.At a global level it is established that richer countries have a stronger consumption pattern than poorer, and thus generate higher levels of carbon dioxide emissions.
Rehabilitering med eller utan simning av korsbandsopererade hundar
This study examines what effect swimming has on the rehabilitation, compared with only
resting after a cranial cruciate ligament surgery. It consists of a literature study, an inquiry
study and a visit to a rehabilitation centre.
The inquiry study shows that ten weeks after a cranial cruciate ligament repair, the
lameness has disappeared in a greater number of dogs among those that undergo
swimming as physiotherapy compared with those that do not swim. Literature shows that
swimming has a positive effect on the result after surgery. The thigh circumference
increases faster, the limb function improves more and the range of motion gets larger.
Dogs should therefore be recommended swimming as rehabilitation after surgery for a
rupture of the cranial cruciate ligament..
Förslag till placering av anläggningar för att förbättra vattenkvalitén i Tidan
Considering water quality, landuse and reducion of wetland area in the watershed of Tidan, areas witch are in need of constructions to improve the water quality are identified. Constructions are suggested to be located within the smaller streams in the watershed, so that the water is treated before it reaches the stream Tidan..
Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen
Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation. In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.
Handel med utsläppsrätter - en granskning av ansökningsförfarandet för tillstånd till utsläpp av CO2
Syftet med detta examensarbete är att beskriva den lagstiftande bakgrunden till handeln med utsläppsrätter samt att granska hur det inledande förfarandet av handelssystemet har genomförts i Sverige..
Några elevers tankar kring ett klassiskt matematiskt problem. : Om problemlösningsförmåga och argumentationsförmåga ? två matematiska kompetenser.
In this thesis we study four groups of students in grade 8, 9 and 10 when they try to solve a classical mathematical problem: Which rectangle with given circumference has the largest area? The aim of the study was too see how the students did to solve a mathematichal problem?The survey shows that students have rather poor strategies to solve mathematical problems. The most common mistake is that students don?t put much energy to understand the problem before trying to solve it. They have no strategies.