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The great properties and clear form makes the circular hollow section (CHS) appreciated by architects. When connecting these sections today it is common to use gusset plates. The knifeplate connection where the gusset plate is inserted into a slot made at the end of a circular section, is the most used connection today. This type of connections is not seen as aesthetically pleasingby architects because of its abrupt cut of the CHS. An alternative for the knife-plate connection is the Crocodile nose connection (CN-connection). The benefits of the CN-connection is the absence of the abrupt cut and the protruding gusset plate, which makes it appreciated by architects. In this connection the CHS’s ends are tapered, which creates two semi-elliptical cuts at both sides of the member. On these cuts, appropriate plates arefillet welded. These plates are shaped and bended so that when they are welded in place, the orientation of the extending part is parallel to the member axis. A gap is made between the extending parts so that a gusset plate can be inserted and bolted together with the member. Four different specimens of the CN-connection are tested in order to find the best shape. Two specimens have a stiffener between the plates, at a small distance from the end of the CHS. The difference between the presence of a stiffener and the lack of it, is investigated. The results showed that the specimens with the connecting piece obtained a much higher ultimate load, up to 413 %higher. Two different angles of the CHS’s cut is also investigated in order to see the most appropriate bevelling angle. In this case the results showed that the specimens with the smaller bevelling angle obtained a higher ultimate load, up to 40 % higher. A check of the weld connecting the plates and the CHS is also performed. This check was made with an assumed calculation model. The results showed that the calculation model only was valid for the specimens without the connecting piece. The calculation model must therefore be enhanced, in order to work for all dimensioning cases. / De goda egenskaperna och den ideala formen gör det cirkulära tvärsnittet uppskattat av arkitekter. Vid anslutningar av dessa tvärsnitt är det idag vanligt att använda knutplåtar. Kniv-plåtanslutningar där knutplåten förs in i en öppning i änden av det cirkulära tvärsnittet är det mest använda förbandet idag. På grund av rörets abrupta slut i detta förband är det inte estetiskt tilltalande enligt arkitekter. Ett alternativ för kniv-plåt-förbandet är Crocodile Nose-förbandet (CN-förbandet). Fördelarna med CN-förbandet är frånvaron av det abrupta slutet och den utstickande knutplåten, vilket görden uppskattad av arkitekter. I detta förband är det cirkulära tvärsnittets kanter nerfasade, vilket skapar två semielliptiska skärytor på båda sidor av röret. På dessa skärytor svetsas lämpliga plåtar med kälsvetsar. Plåtarna är formade på ett sådant sätt att när de är svetsas på plats är orienteringen av den utstickande delen parallel med rörets axel. Ett mellanrum mellan de utstickande delarna skapas så att knutplåten kan föras in och bultas fast tillsammans med röret. Fyra olika provkroppar av CN-förbandet testas för att hitta den bästa utformningen. Tvåprovkroppar har en avstyvning mellan plåtarna. Skillnaden mellan närvaron av avstyvningen och frånvaron av den är undersökt. Resultaten visade att provkropparna med avstyvningen fick enmarkant högre brottlast, upp till 413 % högre. För att även hitta den optimala vinkeln på skärytan har två olika vinklar undersökts. I detta fall visade resultaten att provkropparna med den mindrevinkeln gav en högre brottlast, upp till 40 % högre. Även en kontroll på svetsen som binder ihopplåtarna med röret är gjord. Denna kontroll gjordes med hjälp av en antagen beräkningsmodell.Resultatet visade att beräkningsmodellen endast är giltig för provkropparna utan avstyvningen.Beräkningsmodellen måste därför utvecklas, så den kan användas för samtliga dimensioneringsfall.

M.Ing. / It is of cardinal importance to accept that failure is a fundamental part of every day life. The difference is however, that one does not only need to learn from ones own failures, but also from others’ failures. This is similar to the situation of not working harder, but working smarter. There are several factors within the project environment that can cause a project to fail, but once these factors have been identified the project manager can implement “preventive maintenance” to ensure that these factors do not affect the project. Further investigations on a recently failed project and questionnaires set-up by the author confirm the factors contributing to project failure as discussed in the literature case study. One way to manage these factors is by means of proper project management and risk management, which is a sub-set of project management. This dissertation highlights certain problem areas that can hinder project success and provides recommendations to achieve project success.

The position taken in this thesis is that a small and medium sized supplier makes a strategic choice to integrate their supply chain with industrialized house-building companies in order to deliver customer value and sustain competitive advantage. Customer values for industrialized house-building means delivery reliability, product quality, supply chain and market flexibility. Supply chain integration is the means for understanding customer requirements and to use supply chain resources efficiently through collaboration. The purpose of this thesis is to explore a small sawmill transition from single-minded focus on raw material optimization and increased production efficiency towards supply chain integration and customer focus in the industrialized house-building context. The thesis basis is a systematic literature review and five appended papers, based on a longitudinal case study at a small Swedish sawmill. Data has been collected through interviews, participant observations, and archival data during the period of 2010-2012. The theoretical gap is formed by the lack of consensus on supply chain integration. Viewing the criticism it is not clear how the constructs that constitute supply chain integration affect the possibility of succeeding with integration, how the integration should be measured, or how it affects the performance. Hence this thesis makes a holistic approach and collect empirical data trough method development on a strategic (business models, supply chain management), tactical (supply chain planning, sales and operations planning) and operational (value stream mapping, lean value delivery, simulation) supply chain integration process within industrialized house-building context. However, the findings do not conclusively prove or disprove the position. Findings indicate that small sawmills with limited resources and capabilities can employ methods of sales and operations planning, business model decomposition and value stream mapping enhanced decision making. The main contribution is the empirical data on supply chain integration divided and analyzed from strategic, tactical and operational process levels synthesized that with understanding of the importance of integrating these three levels dual perspective. Thus contribute with theoretical enhancement and reduction of the still-identifiable fragmentation of supply chain integration theory. / Godkänd; 2014; 20140423 (jarkko); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Jarkko Erikshammar Ämne: Träbyggnad/Timber Structures Avhandling: Supply Chain Integration for Small Sawmills in Industrialized House-Building Opponent: Professor Christine Pasquire, College of Art & Design and Built Environment, School of Architecture Design and the Built Environment, Nottingham Trent University, Nottingham, England Ordförande: Professor Lars Stehn, Avd för byggkonstruktion och -produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Tisdag den 17 juni 2014, kl 09.30 Plats: F1031, Luleå tekniska universitet / Lean Wood Engineering, TräIN

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Previous studies on acoustic requirements for performers of classical music proved that early reflections were of critical importance for good ensemble conditions. However, strong early reflections may produce an unpleasant tone quality. Diffusers are sometimes used to reduce the negative effects caused by large specularly reflecting surfaces. The aim of the research project is to better understand what happens when diffusers are applied to the enclosure walls of a stage in a concert hall. Two aspects are examined: the changes produced to the sound field measured on the orchestra platform, and the manner in which musicians perceive diffuse early reflections in comparison with specular early reflections. Results of objective measurements show that the most noticeable property of diffusers on the early sound field is the smoothing of the impulse response. Diffusers attenuate strong early reflections. Besides, diffusers give a better sound energy distribution by providing reflections outside the specular sector: the standard deviation of several acoustic parameters is somewhat smaller with diffusers. It was found that diffusers do not eliminate comb filter effects and that they do not have a great influence on EEL, ST and clarity. The subjective aspect resulting in the greatest consensus among the subjects is the following. The overall tone quality is improved by diffusers. The overall sound quality is influenced by the amplitude of early reflections and by the reception angle of the reflections. Diffusers may also affect articulation, clarity, self and mutual hearing, but to a minor extent. Musicians' requirements regarding the fine structure of early reflections differ according to the size of the ensemble who is performing, the room volume, the power and directivity of the instruments played, and the type of music (or desired tone quality).

Nowadays most people tend to spend a major part of their lives indoors; therefore, the importance of withholding a good internal environment in our buildings is essential. What follows, the thermal indoor climate is strongly influencing the quality and comfort of life in residential areas. This essay will focus on thermal indoor climate situation in a student residence. Based on calculations, measurements and simulations from two different student apartments as well as data collected through a survey, this work will discuss whether the indoor climate complies with the requirements and standards for student housing and what improvement options are available. The survey showed dissatisfaction with the indoor temperature during summer and wintertime. Furthermore, the climate simulation demonstrated the increase in temperature during the summertime, which resulted in a greater dissatisfaction (PPD). Additionally, the calculations made to compare with the climate simulation have also shown that the apartments are getting too hot during summer. IDA ICE logged the relative humidity over a longer period of 1 year, resulting in a range between 5.8% -77.8%. Own measurements such as temperatures, relative humidity, carbon dioxide and exhaust airflows have been set against standards and requirements from authorities and deficiencies of the thermal indoor climate have been mapped. The apartments meet the standard of thermal indoor climate for student housing with one exception -the carbon dioxide content exceeds 1000 ppm in the apartment with the presence of two people. The exhaust airflow in both apartments was lower in our own measurements in comparison to what they were at the OVK protocol from 2014. The exhaust airflow in one apartment had a flow rate of 10 l / s higher than the dimensional flow rate, which indicates imbalance in the system. According to IDA ICE, too high and too low humidity was observed. This may indicate that the apartments do not have a satisfactory sun shading, which plays a significant role in the indoor climate. Using sun shading on all windows could reduce the temperature increase from solar radiation by 50% and the maximum operating temperature could be lowered by 4 degrees in IDA ICE. Using awnings as the sun shading solutions would also lower PPD's high peaks to 10%.

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Buildings represent more than 40% of final global energy consumption, among which 50%-60% of energy consumption is attributed to Heating, Ventilation and Air Conditioning (HVAC) systems. The application of phase change material emulsions (PCMEs) in air conditioning systems is considered to be a potential way of saving energy because with their relatively higher energy storage capacity, they are able to reduce flow rate whilst delivering the same amount of cooling energy. PCMEs can also simultaneously act as cold energy storage to shift peak-load to off-peak time and improve coefficient of performance of systems. However, one of the main barriers affecting the application of PCME is the difficulty in maintaining stability in the emulsions without experiencing any temperature stratification during phase change process. To this end, an innovative energy efficient phase change emulsion has been developed and evaluated. The emulsion (PCE-10) which consists of an organic PCM (RT10) and water has a phase change temperature range of 4-12°C with heat capacity of twice as much as that of water thus making it a good candidate for cooling applications. Particular attention was also paid to the selection of the surfactant blends of Tween60 and Brij52 since they are capable of minimizing the effect of sub-cooling as well as ensuring stability of the emulsion. For the purpose of testing the performance of developed PCE-10 in fin-and-tube heat exchangers, series of theoretical and experimental studies have been carried out to understand the rheological behaviour and heat transfer characteristics of the developed PCE-10 in a fin-and-tube heat exchanger. Both experimental and theoretical results were fairly close and showed that the PCE-10 did enhance the overall heat transfer rate of the heat exchanger. In order to evaluate the potential of the integrated system, whole building energy simulation was carried out with a building simulation code TRNSYS. It was found out that the required volumetric flow rate of PCE-10 was 50% less than that of water which is equivalent to 7% reduction in total energy consumption when providing the same amount of cooling power. Despite its potential in cooling systems, the viscosity of the developed sample was found to be much higher than water which could contribute to high pressure drop in a pumping system. Its thermal conductivity was also found to be about 30% lower than the value for water which could influence heat transfer process. There is therefore the need to enhance these thermophysical properties in any future investigations.