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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Vingkonstruktion till stor RC-modell av C-17 Globemaster

Westholm, Christopher, Magnusson, Markus January 2008 (has links)
Rapporten behandlar konstruktion av vinge till en radiostyrd modell av Boeing C-17 Globemaster III. Modellen kommer att tillverkas för försäljning av företaget Mil tech. Spännvidden på vingen är omkring sju meter och med den storleken kommer den troligtvis bli det nuvarande största radiostyrda flygplan som konstrueras för försäljning. Rapporten beskriver konstruktionsförslag för delning av vinge, bak- och framkantsklaff, skevroder, luftbroms, motorpyloner och de valda lösningarna samt vilken vingprofil som modellerandet utgått från. Rapporten behandlar inte själva CAD-modellerandet. / This report considers modelling of a wing to a radio controlled (R/C) model of Boeing C-17 Globemaster III. The airplane will be manufactured for sales. The wingspan is about seven meters and the airplane will probably be the currently largest R/C-plane made for sales. The report describes design proposal for a wing split, trailing and leading edge flaps, ailerons, lift dumpers, engine pylons and the selected solutions and what aerofoil the modelling started from. The report does not consider the CAD-modelling itself.
92

Kopplingsbeslag för resårbottnar / Hitch for bedframeworks

Memic, Damir January 2008 (has links)
The project has been implemented in collaboration with Carl-Johan Lundberg on Deltagruppen Ltd in Jönköping. Problem introduction comes from Carl-Johan's own experience from the hotel sector. The problem that all hotels has is that they sell two products, i e. simple - and double rooms. Persons that travel in companies do not desire always to share bed. Focus in the work is to develop a product that holds together two simple beds and forms double bed, concurrent that it goes that converters to two simple bed without needing to disassemble the product and be done invisible. A result with the work is a product that meets everyone the nonplussed requirements on function and cost. Keywords:  Cost-effectively  Bed ring  Link confiscating  Single bed  Double bed  Assessment
93

Miljöutredning för Elisolation HTM AB

Röstlund, Jessica January 2007 (has links)
Denna miljöutredning avser företaget Elisolation htm AB, som ingår i Söderberg företagen och är lokaliserat i Laxå, Närke. Företaget bedriver försäljning, tillverkning och lagerhållning av härdplaster och termoplaster med goda elektriska, mekaniska och temperaturegenskaper. Idag är ISO 14001 ett konkurrensmedel som inget företag kan bortse från. Allt fler företag arbetar enligt miljösystemet och ställer därför krav på att även deras samarbetspartners och underleverantörer gör det. Klarar du inte av att möta dina kunders krav så finns risken att de vänder sig till en konkurrent. Detta examensarbete är en miljöutredning som är en del av miljöarbete på Elisolation htm AB och utredningen är det första och grundläggande steget i processen med att införa ISO 14001 i verksamheten. Motivet med en miljöutredning är att ge en nulägesbeskrivning av Elisolation htm AB:s aktiviteter, verksamheter och tjänster som påverkar miljön mest och att identifiera de miljöaspekter som finns på företaget.
94

Validation Methodologies for Construction Engineering and Management Research

Liu, Jiali 11 July 2013 (has links)
Validation of results is an important phase in the organization of a researcher’s work. Libraries and the internet offer a number of sources for guidance with respect to conducting validation in a variety of fields. However, construction engineering and management (CEM) is an area for which such information is unavailable. CEM is an interdisciplinary field, comprised of a variety of subjects: human resources management, project planning, social sciences, etc. This broad range means that the choice of appropriate validation methodologies is critical for ensuring a high level of confidence in research outcomes. In other words, the selection of appropriate validation methodologies represents a significant challenge for CEM researchers. To assist civil engineering researchers as well as students undertaking master’s or doctoral CEM studies, this thesis therefore presents a comprehensive review of validation methodologies in this area. The validation methodologies commonly applied include experimental studies, observational studies, empirical studies, case studies, surveys, functional demonstration, and archival data analysis. The author randomly selected 365 papers based on three main perspectives: industry best practices in construction productivity, factors that affect labour productivity, and technologies for improving construction productivity. The validation methodologies that were applied in each category of studies were examined and recorded in analysis tables. Based on the analysis and discussion of the findings, the author summarized the final results, indicating such items as the highest percentage of a particular methodology employed in each category and the top categories in which that methodology was applied. The research also demonstrates a significant increasing trend in the use of functional demonstration over the past 34 years. As well, a comparison of the period from 1980 to 2009 with the period from 2010 to the present revealed a decrease in the number of papers that reported validation methodology that was unclear. These results were validated through analysis of variation (ANOVA) and least significant difference (LSD) analysis. Furthermore, the relationship between the degree of validation and the number of citations is explored. The study showed that the number of citations is positively related to the degree of validations in a specific category, based on the data acquired from the examination of articles in Constructability and Factors categories. However, based on the data acquired from the examination of articles in the year 2010, we failed to conclude that there existed significant difference between clear-validation group and unclear validation group at the 95 % confidence level.
95

Design, development and implementation of a mechatronic log traceability system

Möller, Björn January 2011 (has links)
This thesis concerns a mechatronic system, designed and developed for the forest industry, to trace logs from forest to sawmill. The research is a key part of a large research project launched by the EU in 2006 called the Indisputable Key project. Wood waste during harvesting, transportation and refinement is a major concern for the wood industry worldwide. Some raw materials are not suited for specific end products, and acknowledging this late in the wood value chain is cost inefficient. Pinpointing specific raw material suitable for a particular end product could increase quality, reduce waste and environmental impact; to accomplish this, traceability is essential. To trace the raw material of a final wood product to its origin, marking and reading of the different specimens must occur at each refining stage in the wood value chain. The traceability chain can be divided into three main stages: forest to sawmill, inside the sawmill, and from sawmill to second manufacturer. The research presented here covers the first part of the wood value chain, namely, forest to sawmill. In Scandinavian countries, logs are cut to length in the forest using a harvester machine. To trace logs, a unique identity code needs to be associated with each log at harvesting time in the forest and detected before further processing at the sawmill. Earlier research using RFID transponders as code carriers have been functionally verified but too costly. Although the cost of RFID transponders is declining, alternative methods are considered a necessity. This constitutes the main driver behind this thesis. The thesis presents a promising alternative log marking method comprising a harvester saw-integrated log code printer and a sawmill code detection system. An identity code in the form of a standard matrix code is applied via the harvester saw bar during cutting. A prototype has been designed and realized and the results point towards a both time and cost efficient solution. The code detection system, to be placed in one or more locations at the sawmill, is based on vision technology and image processing to detect the applied log codes. Both log code marking and reading systems communicate with an ICT system which maintains the traceability database. A major advantage of the system is that both marking and reading is performed without any time-loss and hence do not disturb the high pace production flow in todays forestry. Also, the item cost of each code mark is very low, compared to e.g.a transponder. The marking technology is patent pending. A field test was performed in December 2009 in northern Sweden. A test batch of 320 logs was marked and read. Two code structures (i.e., matrix and barcode) were applied, where 210 barcoded logs were used to demonstrate log traceability between forest and sawmill. This result indicates that this technology has potential. The prototype is not intended for commercial use, but serves merely to demonstrate the potential of the method; further research is needed to improve its functionality. / QC 20110512
96

The Effect of Clay, Cement and Fibers on the Strength and Durability of Compressed Earth Blocks

Banker-Hix, Wyatt Adair 01 June 2014 (has links)
This Thesis examines the effect of soil characteristics, cement content and fibers on the strength and durability of compressed earth blocks (CEBs). This work expands on the available information regarding the constituent properties which affect the compressive and tensile strengths and durability of CEBs. Additionally, little research on the subject of synthetic fibers and their effect on strength and durability of CEBs is available and this work provides an initial study in this area. To study the effects of fibers, as well as confirm the trends of previous research regarding the effects of clay and cement, 27 unique batches of CEBs were pressed and tested using a Vermeer BP 714 block press. Three different soil types and two fiber types were utilized. The compressive strength, modulus of rupture (MOR), absorption, and durability were measured on over 185 specimens. The strength and absorption tests were adapted from common ASTM International test methods for similar materials, while the durability test was a uniquely developed method to quantify durability by measuring mass loss during drying and wetting cycles. After the testing regimen was completed, a trend between clay content and strength could not be determined. Durability testing suggested that as clay content decreases, durability increases. A linear relationship was found between cement content and strength, which was confirmed during durability testing. The addition of different fibers did not have an effect on the peak strength of CEBs, although it appears they may decrease the durability. The gross versus net unit strengths of CEBs were examined due to the unique shape of the CEBs utilized. Additionally, a mathematical expression relating the MOR to the compressive strength was developed.
97

A Gasless Method of Spraying Thermoplastic Resin

Rogers, Dan T. 28 November 2005 (has links) (PDF)
This spraying method for thermoplastic resins is a new manufacturing process for applying thermoplastics to a mold or surface in an efficient way that has the potential of reducing cycle time. Spraying thermoplastic resins is similar to spraying other polymers, such as paint, with the differences being higher pressure and temperature. This method uses an injection molding machine with a modified nozzle to spray the plastic material. In this study, temperature, pressure, and nozzle size were factors that influenced the success of this spraying method. The method of spraying in this study proved spraying without a gas is possible, a statistical analysis of a series of sprayed samples was performed, and a summary of the results is presented. This study is the only known method to use these procedures. The purpose of this thesis is two fold. First, its purpose is to achieve a method of spraying thermoplastic resins without the use of a combustible material. Second, if the spraying method is found to be possible, the thesis investigates what factors, of those selected; have a significant influence on the result? There are other types of spraying plastic methods used currently in industry. One such method, described in the project, is called Flame Spraying. This method, as well as others, has proven to be useful in protecting metals, wood, and other materials from harsh environmental and chemical elements. The results of this study proved that gasless spraying of thermoplastic resin is indeed possible and with further research this method can lead to a new manufacturing process for producing plastic parts or coatings. Future studies can include modifying factors such as temperature, plastic, pressure, tooling, and methods.
98

BIM and Communication: Implementation of Building Information Modeling Into an Integrated Project Delivery Contract to Encourage Project Teams to Communicate

Worden, Kathleen 01 June 2016 (has links) (PDF)
The objective of this thesis is to explore BIM, IPD and their implementation into a building project contract. The Integrated Delivery Processes is comprised of a collaborative team of Designers, Constructors, and Owners working side by side to create a successful project. BIM has been introduced as a technology into the industry, as a tool that these parties can use for better understanding the project. Through case studies of IPD projects using BIM are observed, it was determined that although BIM was used, one problem faced is the lack of BIM standards included initially in a contract for in an IPD project. There are templates available by the AIA, AGC, and USACE, but they are not all standalone documents. A guideline for the parities to discuss will be introduced as conversation piece that would help segue into what might be included in the contract documents.
99

Verifiering av Kedertakstolen

Fornander, Erik January 2010 (has links)
<p>The Kedertruss is the loadbearing part in the Keder weatherprotectionsystem and it has been analyzed concerning its loadbearing capacity. The Kedertruss is produced and manufactured by Wilhelm Layher GmbH & Co. KG and this report has been made for their Swedish division Layher AB.  The Kedertruss, designed in Germany according to German designcode, has been recalculated concerning Swedish conditions according to Eurocodes and a ongoing European standardization project. The two-dimensional program Winstatik Frame Analysis has been used for evaluation of load effects. Capacity has been calculated by hand-calculations and it has been verified that the Kedertruss in its larger spans isn’t able to withstand the loads. The main problem is the greater snowloads which has been proofed to be the most unfavorable load for the Kedertruss. Apart from the commission from Layher AB a parametric controlled model of the Kedertruss has been made in Revit Structure</p>
100

Verifiering av Kedertakstolen

Fornander, Erik January 2010 (has links)
<p>The Kedertruss is the loadbearing part in the Keder weatherprotectionsystem and it has been analyzed concerning its loadbearing capacity. The Kedertruss is produced and manufactured by Wilhelm Layher GmbH & Co. KG and this report has been made for their Swedish division Layher AB.  The Kedertruss, designed in Germany according to German designcode, has been recalculated concerning Swedish conditions according to Eurocodes and a ongoing European standardization project. The two-dimensional program Winstatik Frame Analysis has been used for evaluation of load effects. Capacity has been calculated by hand-calculations and it has been verified that the Kedertruss in its larger spans isn’t able to withstand the loads. The main problem is the greater snowloads which has been proofed to be the most unfavorable load for the Kedertruss. Apart from the commission from Layher AB a parametric controlled model of the Kedertruss has been made in Revit Structure</p>

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