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Acoustic Analysis of Loudspeakers Cavity Including Viscothermal Effects

The geometry of a loud speaker cavity often gets a complicated geometry with sharp corners and narrow ducts. For this kind of shape the internal energy losses caused by viscosity and thermal conduction play an important role in the acoustic behavior. Today there is no method that sufficiently predict these effects. In this report the analogy between the loudspeaker cavity, a simple mass and spring sy

Moisture Induced Stresses and Deformations in Parquet Floors - an Experimental and Numerical Study

The indoor climate conditions in buildings have changed in the last decade due to more efficient climatic systems, floor heating systems and larger open floor areas with more natural light. These factors all give increased annual variations in the humidity and the temperature in parquet floors. Such variations can result in troublesome deformations, glue line delamination and development of cracks

A finite element based design tool for point fixed laminated glass

In this master’s project, a design tool for bolt fixed laminated glass was developed, based on linear-elastic finite element theory. The program produces images of the deflections and stress distributions in bolted glass panes. A two-dimensional triangular mesh, created by an external mesh generator, was extended to a three-dimensional mesh comprising 15-node wedge elements. A least-square method was

Analys av jord och konstruktion i samverkan - Utvärdering av olika FE-program

When building below ground level in cities the regulations regarding deformations of surrounding soil are very strict. When using conventional methods of calculation it is difficult to predict the occurring deformations. This is why it has become more common to use FE-modeling to determine deformations. With FE-modelling it is possible to take the interactions between soil and construction into co

Simulering av betong under härdning

Concrete hardens as a result of chemical reactions between water and cement. Cement is a hydraulic binder, in the reaction the cement binds water-molecules. This is an exoterm process, heat is produced during the reactions. How fast this process proceeds is much depending of the temperature. The amount of heat produced during the hardening of the concrete is also depending on the thickness of the

Finita elementanalys av en brandutsatt fackverksbalk i stål

Det har blivit allt vanligare med direkthandel i stora enplansvaruhus, där kunder plockar sina varor direkt från pallställ. Dessa pallställ går ofta från golv till tak och är lastade med varor ända upp till taket. I taket förekommer ofta fackverksbalkar i stål som bär upp stomsystemet. Vid en eventuell brand i ett pallställ kan det bli stor lokal flampåverkan med snabb upphettning i delar av fackve

Samverkansgrundläggning i relation till pålning

Below every building there is a different type of foundation work, it can comprise point carried piles or floating piles that pursues down the loads in the ground. A foundation work without piles could also be used, but big subsidence can arise in particular at bigger building constructions, it is however most important that the differentiate subsidence becomes too big. These subsidences can influ

Structure as Architecture

Problem: How does collaboration between architects and engineers work? Which are the advantages and disadvantages in the collaboration? How can you make the cooperation better? Object: The purpose of this thesis is to make a connection between architect students and engineers, to find the differences between us and to try to collaborate. We wanted to know how difficult the cooperation could be, i

Design Method for Strut-Beam Connection in Hinged Frames

Glulam is almost exclusively the chosen material of timber frame structures. Of those, three-hinged (three-pin) portal frames are incomparably the most common type. Being both statically determinate and stable against horizontal forces in its own plane offer both practical (basic constructive details) and economical benefits. The design of the haunch allows for various solutions: it can be curved

Numerical analysis of silo discharge

A silo discharge with a bulk material consisting of iron ore pellets is studied. The silo is about 65 meters high and 38 meters wide. The quality of pellets decreases when they are exposed to high stresses while moving. The stresses are therefore not allowed to exceed a certain threshold. It must also be possible to trace the origin of a sample from the discharge. To fulfill these two demands the o

Shear Capacity in Adhesive Glass-Joints

In this report the shear-capacity of adhesive glass-joints was investigated. A number of various adhesives were tested; glues and silicones. Tests were conducted with small specimens to evaluate the characteristics of the adhesives. With the results of the tests material models were evaluated in the finite element program Abaqus. Linear-elastic and hyper-elastic models were used. Large-scale tests

Stress Analysis of PTFE Sleeves in Industrial Valves

The polymer PTFE has become an important and widely used sealing material in the valve industry in recent years. It provides good strength and low friction, but it is sensitive to stress relaxation, i.e. loss of stiffness with time. This in turns may cause problems with leaking seals. The objective of this master’s dissertation is to perform a stress analysis of the PTFE sleeve used in an indust

Stress and Strength Analysis of Curved Glulam Beams With Box Cross-Section

Glulam arches can be used when designing structures with large spans such as halls or arenas. Wood has low density compared to steel and concrete which keeps down the dead weight of the structure. The cross section of glulam arches is often built up as a box-section for efficiency reasons. However, wood shows strongly orthotropic behavior where maximum allowed stress perpendicular to grain is only

Frihet under kameraövervakning? − om individens insyn i bildmaterialet

Problem/Bakgrund: Varför har enskilda individer som fångas på bild av övervakningskameror på allmän plats inte rätt att få tillgång till bildmaterial som de själva förekommer i? Syfte: Uppsatsens syfte är att undersöka huruvida utlämnande av bildmaterial till enskilda individer som fångats på bild av övervakningskameror på allmän plats skulle fungera stärkande för den personliga integriteten hos

Characterisation of LYCCA DeltaE-E-Telescopes

LYCCA is a detector system consisting of different types of detectors which can be used flexibly to meet the individual requirements of different experiments focused on studying exotic nuclei far off the line of stability. It was developed for the HISPEC/DESPEC programme which is part of the NUSTAR collaboration at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. T

Driver Focus

This report incorporates a product styling development concept carried out on Scania a vehicle manufacturer known for its premium long haulage trucks, located in Södertälje, Sweden. The report consists of the development of the writers’ conception and implementation of the term “Driver Focus” on Scanias truck interior. The project is carried out using various different industrial design techniques

Development, Installation and Commissioning of an OCR Verification System - For Order Number and Label Correspondence

Tetra Pak is a large scale organization that provides its customers with a food packaging solution based on laminated carton board in various package formats. The packaging material is produced in more than 50 converting factories represented world wide. The production develops the material in roll form that are loadable in the filling machines. Each roll arrives to the filling site with a barcode

Non Contact Test Points - A high frequency measurement technique for printed circuit boards

A rising problem within electronics today is that, since the frequencies have increased dramatically, it is now very difficult to measure signals. If a traditional probe is used, then the direct contact will destroy the signal. The general idea behind this master thesis project is to make use of the crosstalk between transmission lines to create non contact test points. This thesis aims to evaluat

Beteendemönster och styrelseeffektivitet: Bolagsstyrning i en interpersonell kontext

På grund av svåra metodologiska och praktiska svårigheter domineras forskning om bolagsstyrning i allmänhet och styrelseeffektivitet i synnerhet av relativt ytliga modeller. Så kallade black boxstudier är mycket vanliga, och kontrasteras mest av rent konceptuella modeller utan kvantitativa amibitioner. Den här uppsatsen kikar in i den svarta lådan och utforskar den interpersonella kontexten i styrDue to severe methodological and practical difficulties, research on corporate governance in general and board performance in particular is dominated by relatively shallow models. So called black box studies are very common, and are contrasted mainly by conceptual models without any quantitative ambitions. This paper peeks into the black box, exploring the interpersonal context within the board ro