Aquaponics is a food production system consisting of a consecutive cultivation of plants and aquatic animals, fish or shellfish, in recirculating water. The plants feed on the nutritious effluents from the fish tank and bacteria converts ammonia from the fish tank into nitrate that is absorbed by the plants. The plants receive nutrition and the fish gain purified water. The environmental impact of the production of fish meal and fish oil used in conventional fish feed includes a large consumption of fossil fuels with subsequent carbon dioxide emission. The aquaponic system can be made environmentally sustainable and self-supporting if supplemented with a vermicompost/vermiculture for the production of worm protein as a fish feed. Vegetable waste from the hydroponic part of the system can be reused as worm feed in the compost and the protein rich worms can be harvested, dried and grinded and brought back to the aquaculture as fish feed. As a first step in this direction, I have investigated the effect of recycling of vegetable waste in vermicomposts on the growth and number of earthworms (this was evaluated after harvesting). The hypotheses were that earthworms can be cultivated in the vegetable waste and that by adding manure to the vermicompost it is possible to obtain a nutrient content adequate to support a continuous worm harvest, in other words create a vermiculture. Eisenia fetida and Dendrobaena veneta were grown in 20 L bins containing peat mixed with either poultry or cattle manure. The proportions were 70% peat and 30 % manure. Discarded plant parts from lettuce cultivation was added to the vermicomposts (35 g per week) and water was supplied with 0.8 L per week.

Purpose: The aim of this paper is to investigate whether there are differences between big cities and small cities in adventure tourism. The cities that are studied are Stockholm and Visby.Methodology: The study is based on a qualitative method. We have done interviews and observation. We also used books and internet when collecting information.        Conclusions: The study has shown that differences exist between large and small cities. People seek out the opposite, whether you're from a big city or small town.

The aim of this thesis was to study elderly people?s experiences of and approach to their usage of home care services with tax deduction. The aim was also to describe how elderly people reason about their underlying motives of using home care service with tax deduction. The study is based on six qualitative interviews with people between the ages of 65 and 80, living in Nacka, Sweden. This thesis is a collaboration with Stiftelsen Stockholms la?ns A?ldrecentrum/ Stockholm Gerontology Center and part of their follow up study concerning simplified administration for elderly people applying for home care services in Nacka.

AimThe main aim of this study was to find out how teachers reflect on their work with developing pupils? interest towards mathematics in grade nine. As a teacher in mathematics, it is important to be aware of different views on interest towards mathematics and how it is possible to work in that direction. Since developing interest towards mathematics is written the in syllabus as criteria for teaching mathematics in grade nine, it is important to know and take an active role in finding ways to approach the issue.Main issues? How do teachers in grade nine reflect over their work with development of interest towards mathematics?? How are teachers? Beliefs Systems reflected in their work with interest?MethodThe main focus of this study was teachers? perspective on their own work on developing interest towards mathematics.

Introduction: Studies have shown that women are not always satisfied with the effects of contraception and that contraceptive advice is perceived as non-specific. Aim: The purpose of this study was to investigate what contraceptive women have chosen to use in the different phases of their reproductive lives, and what they felt had influenced their choice. Method: A retrospective cross-sectional comparative study with a quantitative approach. A survey with fixed and multiple-choice options was sent to five hundred 45-year old women. Result: The study shows that various birth controls are different in the normal reproductive life.

The purpose of this paper is to examine how teachers choose to work with the teaching of reading and writing skills, how teachers justify their choice of teaching method and how the documentation of student development is being used. This paper also discusses the definition of reading and writing, phonological awareness and how different reading- and writing educational methods can be combined. The gathering of information has been done through a literature review in which I have looked at past research on reading and writing. I have also conducted qualitative interviews with teachers involved in literacy learning. The result of my research shows that it is not possible to determine which literacy learning methods that are most effective.

Gamification är en strategi som använder spelmekanismer och spelkomponenter för att skapa motivation och engagemang hos användare av olika typer av system. Denna studie syftar till att undersöka om gamification kan användas för att motivera användare av system för tillverkningsindustrin.Studien har genomförts med en initial litteraturstudie och kvalitativa intervjuer med experter inom gamification samt utveckling av system för tillverkningsindustrin. Intervjufrågor har därefter ställts mot tidigare genomförd forskning, för att identifiera möjliga resultat.Resultatet av denna studie visar att spelmekanismer och spelkomponenter skulle kunna användas i ett system för tillverkningsindustrin, förutsatt att det finns ett tydligt affärsmål, mätbar och användbar data samt identifierade drivkrafter hos organisationens maskinoperatörer. Vidare har ett antal punkter identifierats som kan vara motiverande för en användare av system för tillverkningsindustrin:Möjlighet för operatörerna att följa utvecklingen i sitt expertområdeKartläggning av operatörernas drivkrafter, vilken därefter används för att förbättra operatörernas arbetssituation, med exempelvis mer givande uppgifterBelöningar som utdelas är matchade mot operatörernas preferenser, med syfte att vara mer effektiva som motivationsskapare.

This report describes a master thesis performed at Saab in Arboga. The main purpose was to build a controller for a system containing a turn table and an antenna beam. The idea is to use this system on a boat where it will be exposed to position disturbances due to waves. The desired behaviour is that antennas placed on the antenna beam should point towards the same target all the time. To solve this problem the system has been modeled and simulated in Matlab and Simulink.

A system for sampling of alcohol and aldehyde from diluted exhaust gases from vehicles powered by ethanol has been developed and tested. The major part of the work has been research of earlier work in the field and the construction of the sampling system.The part of the system constructed for the measurement of alcohol has been shown to work, however, more test should be performed. The part of the system constructed for the measurement of aldehyde was tested parallel to a commercially available system, based on the same principle of measurement, and has been shown to work well.Determination of the concentration of gaseous ethanol using a FID has shown the since earlier known fact that a FID is not able to measure a correct concentration of ethanol. Furthermore it has been shown that high concentrations of gaseous ethanol can not be kept in a bag more than a few minutes without a substantial decrease of the measured concentration..

A cars powertrain consists of everything that is needed for its propulsion. The components in the driveline that transfer the power from the engine to the driven wheels are not absolutely stiff, hence they will wind up due to the torque and act as torsion springs. If you suddenly demand a bigger torque by stepping on the accelerator pedal, a so called tip in manoeuvre, and that torque is acquired from the engine as quickly as possible, the driveline will not be able to transfer that fast torque change due to its weakness and as a result it will start to oscillate. These oscillations will be transferred to the driven wheels and make the car to accelerate jerkily which will be experienced as uncomfortable by the passengers. Furthermore, there is a backlash in the driveline that will make the weakness in the driveline even more excited than it should have been if the backlash did not existed.To avoid too big problems with these oscillations there is a control system that controls the demanded torque.

Syftet med uppsatsen är att undersöka vilken betydelse och påverkan samtalet med studie- och yrkesvägledaren har för utlandsfödda elever med icke svenska föräldrar som är sent anlända till Sverige. En kvalitativ forskningsmetod har används. Fakta har inhämtats via elevintervjuer bestående av åtta informanter från en mindre kommun. Urvalet utgjordes av grundskoleelever i årskurs nio som gjort sitt gymnasieval samt gymnasieelever från årskurs ett och årskurs tre. Resultat och analys indikerar att eleverna tycker att samtalet är betydelsefullt, eleverna får svar på frågor, får faktainformation och detta leder till ett bättre beslutsunderlag i valsituationer.

When developing software that is meant to be distributed over several different computers and several different networks while still working together against a common goal there is a challenge in testing how updates within a single component will affect the system as a whole. Even if the performance of that specific component increases that is no guarantee for the increased performance of the entire system. Traditional methods of testing software becomes both hard and tedious when several different machines has to be involved for a single test and all of those machines has to be synchronized as well.This thesis has resulted in an exemplary application suite for testing distributed software. The thesis describes the method used for implementation as well as a description of the actual application suite that was developed. During the development several important factors and improvements for such a system was identified, which are described at the end of the thesis even though some of them never made it into the actual implementation.

As companies grow, their need for computing power will increase, which traditionally resulted in companies having to invest in more IT resources. Now, with cloud computing, companies can easily hire computer power over the Internet, on-demand. Cloud computing offers a highly scalable environment where companies can store data and host their services. This paper employs a qualitative study with interviews and literature studies to explore opportunities and challenges associated with cloud computing from a system developer perspective. The aim of the paper is to find out how cloud computing changes the conditions for system development. The paper contributes with four different opportunities and challenges that the system developer must handle to succeed in the world of cloud computing.

A large amount of our time is spent indoors in an artificial climate. To make the experience pleasant there are requirements on the ventilation and the heating system. At the present time the most common form of heating is a radiator system complemented with a ventilation system. A ceiling heating system with combined heating and ventilation can replace the two separated systems. The benefit with a ceiling heating solution is that it saves space since the radiator system is no longer needed.

The thesis describes a completely new biofuel system to generate particle-free heat from combustion of ash-containing biofuel particles at high temperatures.The suggested system gives opportunities to introduce biofuels in new areas.Main components in the suggested system is a heat radiating combustion chamber intended for pulverized wood, combined with regenerators to extract heat from flue gases and simultaneously preheating the combustion air.The thesis contains a description of the suggested system, theoretical considerations, calculations regarding the combustion, and includes results from tests performed.The results from calculations and tests performed concludes that the system is workable and possible to apply..