The purpose of this project was to further develop and complete a quadcopter that had been built in an earlier course at KTH, so that it could be used for demonstration and education at the school. The quadcopter was at the beginning of the project completed when it came to hardware, and there was some software functionality implemented but no system for automatic stabilization. The main goal of the project was to implement such a system, and to combine it with the previous functionality to make the quadcopter operable and able to fly. To create a functioning and stable ground multiple basic software features has been implemented, and on top of that additional software to improve the safety, stability and functionality. The most important part is the control system that is responsible for converting sensor and control signals to suitable motor values.

The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.

I föreliggande studie undersöks hur användare upplever användbarheten i ett säkerhetskritiskt system ? Luftfartsverkets flygledningssystem SIGMA. Utifrån litteraturstudier definieras begreppen användbarhet och säkerhetskritiska system. Empirin utgörs av intervjuer med användare av SIGMA-systemet. Studien visade att användarna upplever att systemet i väsentliga delar har bra användbarhet, vilket utifrån litteraturstudier, intervjuer och efterföljande analys främst tycks bero på att systemet arbetats fram med stor användarmedverkan och att det var utarbetat specifikt för arbetsplatsen.

Värmekollektor in Sunne is a company whose main occupation is to collect the gas produced inlandfills. The gas contains about 50 % of Methane which is a greenhouse gas 20 times worse than CO2and should therefore not be allowed to leak into the atmosphere. The Methane is in as large amount aspossible used in different plants for example heating of households. But there are occasions when aflare is needed to burn the excess gas at standstills or testing of new landfills. The Flare only burns themethane to reduce the hazarder?s effect of the environment, it does not take advantage of the energy inthe gasThe goal of this master thesis was for me to create a foundation for an in-house production offlares for Värmekollektor.

The efficiency of the harvesters work is more often reviewed, than the work of the forwarders. In a local Stora Enso office the differences between the harvesters reported volume of timber, and the actual volume delivered to the industry had been noticed. Therefore, the decision was made to do a review on the forwarders work. The review was conducted together with a worker from Vmf Qbera, who is working daily with wood measurement, in order to get a valid evaluation of the logs. Eight sites were included in the survey, and on each site 50 logs were marked. Approximately one third of the marked logs were pulpwood, and the remaining logs marked were timber.

This project was initiated by a veterinarian, that at stallion performance tests for breeding during a number of years, noted breed differences in various types of testicular disorders. Therefore it was of interests to examine the proportion of testicular disorders within certain breeds. The aim with the project was in a first part to study cryptorchidism in common horse breeds in Sweden. Information about castrations of stallions performed during a 10 year period (2000-2009) was collected from computerized case records at five animal hospitals. The case records showed the numbers of castrations, normal cases and cases preformed on stallions with cryptorchidism, abdominal respectively inguinal.

Elever ska enligt kursplanerna i teknik få förståelse för de tekniska system de möter i sitt dagliga liv. Genom att eleverna får kunskap om teknik i allmänhet och tekniska system i synnerhet får de möjlighet att påverka sina liv som medborgare i en demokrati. I litteraturen saknas idag studier om elevers uppfattningar om tekniska system. Syftet med detta examensarbete är därför att studera vilka vardagsuppfattningar elever har om de tekniska system de möter i vardagen. Studien utgår från systemteori vilken ger en möjlighet att utnyttja det gemensamma mönster som kännetecknar analys av system.

The aim of this thesis was to answer a number of questions about the environmental consequences of aircraft de-icing. A further aim was to suggest how the environmental consequences due to the release of de-icing fluids can be measured and reduced.The main impact of the aircraft de-icing on the environment is due to the large oxygen demand for the degradation of glycol based de-icing fluids which are released in the environment. The effect of the increase in oxygen demand depends on where the degradation occurs in the ecosystem. In a sensitive ecosystem, the large demand of oxygen could provide an anaerobic environment which would be harmful for many types of organisms.In order to reduce the negative effects of the applied de-icing fluid, there is some type of collection system at every regular airport in Sweden. The methods of collection can be divided into two general groups, hydrological isolation or vacuum sweeper trucks.

Today, individual indoor stalls and individual outdoor paddocks are the most common way to house horses in Sweden. The way that we manage, house and feed the horses are not optimal for the species natural basic behavioural needs. However, the awareness of this grows in the context of research and the emergence of alternative housing systems. One of the alternatives to the traditional format in individual boxes is called group housing. Group housing systems allow horses to live in herds and they can choose how they want to distribute the hours of the day between movement, resting and foraging. The purpose of this study is to examine how frequently the young horses in a group housing system use the indoor lying area.

Computer based information systems play an important role in modern military combat vehicles. The crew needs to be able to quickly get information about both the vehicle and its outer surroundings in order to quickly make the correct decisions. In this report, we describe the development of a prototype new information system for the BvS10 vehicle, manufactured by BAE System Hägglunds AB in Örnsköldsvik.An important aspect of the system is the time it takes from the point that the information is generated by the vehicle sensors until it is presented to the user. The system must be able to ensure that it never displays information that is out of date. Thus, it is important to create a layer and component based architecture for the solution, making it possible to control, in detail, the information?s age as it moves through the system.

Denna uppsats handlar om hur två länsmuseer samarbetar med äldrevården. Anledningen till att jag valde detta ämne var att jag upplever att äldre personer och äldreboenden sällan diskuteras i litteraturen och undervisningen. Syftet med uppsatsen har varit att undersöka hur samarbetet mellan äldrevården och respektive museum ser ut samt att på ett mer teoretiskt plan undersöka vilka minnen som stimuleras och hur man kan koppla teman och föremål till Performance theory. Mina frågeställningar överensstämmer med syftet, de handlar alltså om hur samarbetet ser ut, vilka minnen museerna vill stimulera och hur man kan koppla teman och föremål till performance theory. Mina teoretiska utgångspunkter har således varit performance theory, teorier om personligt och kollektivt minne samt reminiscensmetoden.

Forest enterprises have always searched for ways to improve efficiency. For the past few years there has been an emphasis on stock-keeping levels. Increased demand for fresh round timber and the need to decrease the amount of tied-up capital has made the forest industry reduce its inventory levels. This has brought on a higher demand on the timber supply from the forest management districts concerning both delivery in time and assortment output. As a result, the flow of timber has fluctuated a lot with serious consequence for the timber supply during 1994.

This thesis examines the subject of reference interviews and the ways librarians form an opinion of users information needs. Using literature and interviews with three librarians I look at the questions below: - Why and when are reference interviews needed? - What significance do they have? - What ideas exist about the performance of reference interviews? - Are there any differences in librarians views of the questions above compared to views in the literature? Results from literature studies and interviews show that reference interviews can be important when librarians try to find out more about users information needs. However its neither necessary nor possible to analyse all reference questions. Librarians therefore need to determine if a reference interview is needed or not.

This thesis studies the negative impact that control signal saturation may have on a controlled system. Different methods that are used to compensate for this problem are also studied and evaluated. Both sensitivity to disturbances and the effect the method has on the systems'ability to follow a reference signal will be examined. Stability will be discussed, but no conclusions whether the systems are stabilized or not can be drawn. Control signal saturation will lead to a slower behavior in general.

When using the digital halftone proofing systems, a closer print match can be achieved compared to what earlier couldbe done with the analogue proofing systems. These proofing systems possibilities to produce accurate print match canas well lead to producing bad print matches as several print related parameters can be adjusted manually in the systemby the user. Therefore, more advanced knowledge in graphic arts technology is required by the user of the system.The prepress company Colorcraft AB wishes to control that their color proofs always have the right quality. This projectwas started with the purpose to find a quality control metod for Colorcraft´s digital halftone proofing system(Kodak Approval XP4).Using a software who supports spectral measuring combined with a spectrophotometer and a control bar, a qualitycontrol system was assembled. This system detects variations that lies out of the proofing system´s natural deviation.The prerequisite for this quality control system is that the tolerances are defined with consideration taken to the proofingsystems natural deviations.