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.

Aim: The aim of this study was to examine a way to measure students? knowledge development by using a self-made measure instrument based on William Doll?s postmodern curriculum.Question: Is it suitable to use an self-made measure instrument based on William Doll?s post-modern curriculum theory to measure development of knowledge?Methods: The study was based on process-hermeneutics and was focused on analysingcollege students? written and oral reflective thoughts. The data was collected over three lessons, where six students? written reflective thoughts were handed in. An observation was carried out each lesson for an extra control of validity.

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.

This master thesis work was done at Saab Underwater Systems AB, a company at the cutting edge of underwater technology. Here torpedoes and other underwater vehicles are developed and manufactured. The major customers are navies of different countries, mostly the Swedish navy. The aim of this master thesis is to develop, construct and evaluate an automatic Trim System for Unmanned Underwater Vehicles. The task of the system is to change the position of the centre of mass and the vehicle?s total mass or volume.

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.

As break downs of production transformers are costly and often result in long outages it is essential for reliability of operation that the transformers are manufactured to be robust. The aim of this M.Sc. thesis is to investigate if deviations should be made from the standard IEC 60076 ? Power Transformers in order to describe a robust large power transformer for procurement.The investigation has been conducted in three stages. In the first stage a definition of the term robust was developed in consultation with the client Vattenfall Vattenkraft.

The regulations for energy consumption are consistently getting more and morestrict. This leads to a higher customer demand for energy analysis early in the buildingdesign process. Many building planners and architects use powerful modeling softwareto visualize their projects. These digital models contain sufficient information aboutthe building?s physical characteristics for reliable energy analysis.

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.

Latent heat storage is a way to store thermal energy when a phase change material undergoes a phase change. The advantage of latent heat storage is the capability to store more energy per mass unit than other heat storage methods. The most commonly used phase change in latent heat storage is the transition between solid and liquid. Phase change materials can be divided into organics, inorganics and eutectics.In the Nordic electricity market the price of electricity is set every hour by Nordpool spot, which leads to price fluctuations because of changes in demand. The main goal of this report is to create a latent heat storage system in a single-family home and investigate the possibility to save money by charging the latent heat storage system when the price of electricity is low, and discharge when the price is high.The thermodynamic model consisted of a ?tube-in-tube? heat exchanger with phase change material in the outer tube and water as the heat transfer fluid in the inner tube.

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.

Diagnosis means detection and isolation of faults. A model based diagnosis system is built on a mathematical model of the system. The difficulty when constructing the diagnosis system depends om how the model is formulated. In this report, a method is described that rewrites the model on such a form that the construction of the diagnosis algoritm is easy. The model is transformed by two state space transformations and the result will be a system on state space form where one part of the system becomes easy to supervise.

VSEM project and the need for a more efficient way of handling requirements andinformation are highly apparent.The overall objective of this thesis is divided into two parts:1. To identify criteria/factors leading to a successful introduction of an informationmanagement system.2. To develop an implementation process for a requirement management system ?the first step towards a PLM system in EE development at VCC.This will be done through interviews with employees, a literature review and an analysisof studies of three earlier projects within VCC.The conclusion of this study shows the great need for change in work methods fordesigners handling information and requirements. An implementation process has beenidentified with guidelines on how to handle different phases of the process.

The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.

We have carried out a study of a classification system for the Swedish collection at The Royal Library in Stockholm from 1887. It was printed in 50 copies. The constructor, Bernhard Lundstedt, and his colleagues used it as guidance in lack of a catalogue. We regard it a local classification system. Little research has been done on old classification systems, but Francis Miksa points out the importance of examining them.

This degree project deals with the creation of a business system for Gamersneed Sweden. The system is divided into two parts, one windows appliction and one websolution..