Sökresultat:
1093 Uppsatser om Cold climate - Sida 25 av 73
Modellering av manövercylindern för Nosstället på JAS39 Gripen
When models are used to describe physical phenomenon during development or modification of a technical system, it is often possible to reduce both the time needed and the overall development cost. With the use of models it is also possible to investigate the potential of the selected solution, without the need for any expensive details and testrigs. In many cases it is also not possible to test all the aspects regarding the functionality that are desired from the system, without using the complete and final product.In this case a model based approach has been used to optimize the different parameters in the new snubbing mechanism for the Nose Landing Gear Retract Actuator on the JAS39 Gripen.During the simulations, upper and lower boundaries were calculated for the length of the spring and the diameter for the restrictor. The governing constraints were given by the requirements for the retraction time during cold conditions and that the amplitude of the alternating loads in the uplock mechanism were brought to an acceptable level.The most promising results from the simulations were then used in a limited number of trials in the hydraulic rig to verify that the configurations comply with the requirements.The final parameters for the snubbing mechanism were chosen to 35±1mm for the spring and 0.4-0.5 mm diameter for the restrictor..
Staden som dött två gånger- en analys av Pompeji och dess bevarande
This essay concerns the site of Pompeii and its preservation. The aim is to investigate what causes the decay of the ruins, how to prevent it and what consequences the tourism has on the site. The material consists of interviews with three Swedish scientists who are currently working with documenting a block in Pompeii. The result reveals a large number of threats against the city, such as climate, tourism and an inadequate economy situation. Examples of solutions are more investments which can be used for restorations and reconstructions, and guards to prevent vandalism.
Energi med fokus på synergi : fallstudie: Lunds Tekniska Högskolas campusområde
Energiarbete handlar inte bara om att energieffektivisera byggnaderna utan även om att skapa platser med god energi som gör att vi mår bra och vill vistas där. Vid energi- och miljöarbete där utemiljön är det centrala arbetsmaterialet kan man få fl era synergieffekter. Energi finns överallt. Det handlar inte bara om att gröna tak och väggar kan ha en isolerande funktion, utan på köpet får man mer funktionsanpassade utemiljöer som kan förbättra livsmiljön.Genom att klimatplanera, som innebär att vi på smarta sätt planerar utemiljön och använder oss av träd, buskar, klätterväxter, grönytor, dagvatt en och refl ekterandematerial kan vi minska behovet av energi egentligen utan att förändra vårt beteende. Däremot behöver vi dessutom ändra vårt beteende för att uppnå en större effekt av klimatplaneringen.
Kemiskt försvar mot havstulpanskolonisering i marina svampdjur
The purpose of this project is to analyze and study the absorption of the substances ivermectin, spinosad and barettin to hydrophobic and hydrophilic surfaces, and to analyze and study if the barnacle larva are effected when they try to settle on the treated surface.Incubation tests with barnacle larva in Petri dishes were performed as well as absorption tests on hydrophobic and hydrophilic surfaces which were tested with ellipsometry. To determine the surface thickness.The barnacles were placed in hydrophobic as well as hydrophilic Petri dishes that had been incubated with ivermectin, spinosad or barettin. After four to six days the larva was counted to analyze the settling. From the results conclusions could be drawn about the adsorption abilities of the substances to the different surfaces.The barnacles were placed in hydrophobic as well as hydrophilic Petri dishes that had been incubated with ivermectin, spinosad or barettin. After four to six days the larva was counted to analyze the settling.
Civilsamhället i Singapore : en demokratiseringskraft att räkna med?
Essay in political science, D-level by Lisa Kringsberg, spring semester 2008.Tutor: Michele Micheletti.?Civil Society in Singapore? can it make democratization possible?The third wave of democratization and the end of the cold war has together increased the interest of the civil society as an impact on democratization. Singapore is a country which is higly-developt in both the socie-economic and economic field. Dispate this Singapore has not yet achieved to become a democratic state. The purpose of this essay is to study how the civil society can affect democracy in a country.
Honlig reproduktionsfysiologi hos lodjur (Lynx lynx)
Knowledge in reproduction in the Swedish lynx (Lynx lynx) is important forseveral reasons. Situated on top of the food chain, lynxes may be at risk of beingexposed to environmental toxins that could have adverse effect on reproduction.The population of lynxes is today managed by restricted hunting which demandsknowledge about both the lynxes numbers and their reproduction. In addition,lynxes may function as indicators of climate change for instance if their season ofheat would be earlier or prolonged due to a warmer climate. Today?s knowledgein reproduction in Swedish lynx is mainly based on information gathered fromradio collared animals.
Fred och säkerhet? : En studie om det Svenska Försvaret utifrån tre perspektiv, Bonsdorff, Andrén och Clausewitz
Following an increase in hostile foreign activity. The discussion regarding Sweden?s defense force´s ability to perform its task has come to a new heading. With the end of the cold war as a major revolution in matters of international security, a major overhaul has taken place to transform the static total defense plan of the nation to a less rigid operational system.Following an analysis of the budgets total amount from the governments of 2002 until 2015 it is clear that while the amount of resources has never directly been lowered, it has shrunk in relation to the countries total GDP. The possible futures for the defense of Sweden bring three possibilities forward in correlation three unique perspectives on military and political policy.Out of the three possibilities the focus on military strength as a political resource seems to be garnering the most support with the latest incursions made my foreign submersibles and the ever growing presence of 5th generation of warfare.
TILLFÄLLIGA EFFEKTTOPPAR I FJÄRRVÄRMEN : Kan man med hjälp av lagrad värme undvika att de uppstår i betonghus?
Climate and environmental issues is now high on the agenda. We live in a generation that must try to solve some major environmental problems. Buildings and habitations account for approximately 40 % of Sweden's total energy today. To reduce this figure, as needed, more research in the field of energy efficiency is required.This thesis concerns the heating of buildings. The load on district heating is heavy during certain times of the day.
Designoptimering, Energi och inomhusmiljösimuleringar i en integrerad BIM-projektering / Designoptimiation, Energy and indoor simulations in an integrated design work
Syftet med en integrerad projekteringsprocess är att information tidigt skall tas fram och att projektörer skall kunna arbeta parallellt, exempelvis genom en gemensam BIM-modell. Revit och IDA Indoor climate an energy, även kallat IDA ICE, har i denna rapport visat sig vara två mycket effektiva verktyg som tillåter att information både kan tas fram, i form av energianalyser, men även kommuniceras digitalt med hjälp av så kallade IFC-exporter.
Då projektörer får möjlighet att jobba i en gemensam modell kan de arbeta parallellt vilket innebär att information kan tillföras både tidigare och snabbare i projekteringsprocessen. I Revit kan arkitekten enkelt skapa olika utformningsförslag och jämföra dessa med avseende på energianvändning. Analyser från denna studie har visat att energisimuleringar i Revit kan användas för att utforska olika utformningsalternativ och därmed finna optimeringsmöjligheter med avseende på energi och inomhusmiljö.
Optimalt ekologiskt : att gestalta praktfulla parker som kan skötas på ett hållbart sätt
This is a graduate work at the Swedish University of Agricultural Sciences, The Department of Urban and Rural Development, Ultuna. The purpose of this paper has been to find out and describe principles for designing parks that offers good recreational and aesthetical values and require little amount of carbon dioxide emissions during their maintenance. The purpose has also been to see if it's possible to use city wastewater in some extent to assure the plants water supply and to find other means to make it less necessary to use purified water for watering.
Recently made studies as well as older ones show how important green areas are in dense city structures both from a health and a climate perspective. Trees and other plants adsorbs different forms of air pollution and can also lower the temperature in the surrounding area through their transpiration.
Av egenintresse eller solidaritet? - Gulfkriget ur realistiskt och liberalistiskt perspektiv
AbstractIn this theory-testing case study I will analyze and discuss the Gulf War which took place in the Middle East in 1990-1991 and has become an important topic for discussion among IR scholars in the post-Cold War era. The events that led up to the Gulf War, as well as the war itself, will be analyzed from two different perspectives; Realism and Liberalism. Within these differing theoretical frameworks I have chosen to use elements from, on the one hand, Classical and Structural Realism, and on the other hand, Idealism and Liberal Institutionalism. Focusing on these specific schools of thought I aim to derive essential, ?key?, concepts that will then be tested against empirical fact.The overall purpose of this study is to try to logically explain, through detailed analysis, the actions of the actors involved in the Gulf War and, in addition, why this war ever occurred.
MOLNU : Att utveckla ett gemensamt gränssnitt
Climate and environmental issues is now high on the agenda. We live in a generation that must try to solve some major environmental problems. Buildings and habitations account for approximately 40 % of Sweden's total energy today. To reduce this figure, as needed, more research in the field of energy efficiency is required.This thesis concerns the heating of buildings. The load on district heating is heavy during certain times of the day.
Kartläggning av snökanoner över Östersjön
Convective snowbands is a weather phenomenon that is associated with heavy snowfall in a limited area. They are formed over ice-free parts of e.g. the Baltic Sea when there is a cold easterly airflow over relatively warm water. These convective snowbands can cause large amounts of snow along the Swedish east coast, often causing traffic hazards. Sometimes they can even paralyze an entire community. In this study, convective snowbands that have formed over the Baltic Sea during the period 1980-2009 are examined, in order to find out how often they occur, what place they are most common and in what month they usually appear.
Högt hus i Chongqing/Kina - ett bostadsprojekt
This is a project showing a proposal on how a high-rise building gains qualities similar to middle rise houses of 7-9 stories. The closed, isolated and often anonymous life in the high building opens up through gardens. The resident meet the outdoor environment on the balcony, or has direct access to a garden.Instead of moving in a closed core, the resident will meet the climate and outdoor conditions as soon as he or she leaves the apartment.The project consists of two parts, where the first is presenting a building proposal, the second is expanding the knowledge through background research. The topics are history concerning the skyscraper and the skyscraper globally, closing up with the situation in China..
Hållbarhetsredovisning : Med fokus på negativ information
To establish sustainability reports is an increasing trend for more and more companies. This has led to a spread of the international framework Global reporting initiative, GRI, guidelines to make a sustainability reports. This trend has got a lot of critics from various stakeholders who believe that companies in these reports communicate the information in a way of window dressing. Both negative and positive information has to be represented according to GRI: s principle of balance. Window dressing is created by adding a greater emphasis on the positive information. The researchers review the context of the negative information to study the extent to which it is reported and whether there are patterns and variations in the reported information.