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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.
61

En jämförelse av koldioxidutsläpp i en byggnads klimatskal beroende på val av isoleringsmaterial / A comparison of carbon dioxide emissions in a building´s external shell related to selection of insulation materials

Rydin, Sara, Olsson, Sofia January 2019 (has links)
Syfte: En betydande del av Sveriges totala växthusgaser kommer ifrån bygg- och fastighetssektorn. Då livscykelperspektivet är ett högaktuellt ämne är det intressant att implementera LCA i bygg- och fastighetsbranschen och genomföra en analys på de isoleringsmaterial som anses vara de traditionella inom branschen. För att resultatet av LCA ska vara applicerbart för företag i branschen är det också av intresse att veta hur LCC skiljer sig mellan de jämförda isoleringsmaterialen. För att resultatet ska vara lätt att identifiera är en sammanställning av kostnad i kontrast till koldioxidutsläpp av intresse. Målet med studien är att bidra med kunskap om olika isoleringsmaterials miljöpåverkan utifrån ett livscykelperspektiv. Likaså att se hur stor skillnad det blir i kostnad mellan isoleringsmaterial med mer eller mindre koldioxidutsläpp, där en förutsättning är att U-värdet är detsamma för de jämförda materialen. Metod: De vetenskapliga metoderna för studien har varit litteraturstudie, fallstudie och dokumentanalys. Som komplement till dessa har beräkningar, livscykelanalyser och livscykelkostnadsanalyser genomförts. Resultat: Lösull av cellulosa minskar koldioxidutsläppet för isoleringen i vindsbjälklag med 94,6 procent till en kostnadsökning motsvarande 30 procent jämfört med stenull. En skiva av cellulosa minskar koldioxidutsläppet för isoleringen i yttervägg med 94,4 procent till en kostnadsökning motsvarande 7 procent jämfört med stenull. En bottenplatta av cellglas minskar koldioxidutsläppen med 65,1 procent till en kostnadsökning motsvarande 55,2 procent jämfört med en bottenplatta av cellplast och betong. Konsekvenser: • Isolering av cellulosa har ett betydligt lägre koldioxidutsläpp än stenull. • Livscykelkostnad för cellulosa är något högre än för stenull. • Utifrån denna studie rekommenderas att prioritera miljö framför kostnad och därför använda cellulosa som isolering i byggnader. • Cellglas är ett miljömässigt hållbart alternativ till cellplast och betong vid grundläggning. • Cellglas har en högre livscykelkostnad än cellplast och betong vid grundläggning. • Utifrån denna studie rekommenderas att prioritera miljö framför kostnad och därför överväga att använda cellglas vid grundläggning av byggnader. Begränsningar: Undersökningen har inte tagit hänsyn till transporter av material. Livscykelanalyserna är gjorda på 1 m2 material med en bestämd tjocklek. Endast två isoleringsalternativ per byggnadsdel har jämförts och hänsyn till materialens fukt-, ljud och brandegenskaper har inte beaktats. Studien är kvantitativ. / Purpose: A big part of the greenhouse gases from Sweden comes from the construction and real estate sector. Since the life cycle perspective is a high currant subject it is interesting to implement LCA to the building industry and perform such an analysis on the insulation materials that are traditionally used in the building industry. To make the result of the LCA applicable for companies in the industry it is also of interest to know how the LCC differs between the compared insulation materials. For the result to be easy to identify it is necessary to make a compilation of the cost in contrast to the carbon dioxide emissions. The goal of this study is to contribute with knowledge about the environmental impact from a life cycle perspective of different insulation materials. As well to see how the cost might change between different insulation materials with more or less carbon dioxide emissions, where a presumption is that the U-value is the same for the compared materials. Method: The scientific methods for the study have been literature study, case study and document analysis. As a complement, calculations, life cycle assessments and life cycle cost analysis have been made. Findings: Loose fill insulation of cellulose reduces the carbon dioxide emissions for insulation in the attic with 94,6 percent to a cost increase of 30 percent compared to stone wool. A board of cellulose reduces the carbon dioxide emissions for insulation in the external wall with 94,4 percent to a cost increase of 7 percent compared to stone wool. A foundation with foamglas reduces the carbon dioxide emissions with 65,1 percent to a cost increase of 55,2 percent compared to a foundation of EPS and concrete. Implications: • Insulation of cellulose have much lower carbon dioxide emissions than stone wool. • Life cycle cost for cellulose are a bit higher than for stone wool. • From this study the recommendation is to prioritize the environment above the cost and therefor use cellulose as insulation in buildings. • Foamglas is a more sustainable alternative to EPS and concrete for foundations. • Foamglas have a higher life cycle cost than EPS and concrete for foundations. • From this study the recommendation is to prioritize the environment above the cost and therefore consider to use foamglas for foundations. Limitations: The study has not included transportations of the materials. The life cycle assessments are made on 1 m2 of material with a fixed thickness. Only two insulation materials in each building part have been analyzed and no regards have been taken to the materials moist, sound, and fire attribute. The study is quantitative.
62

Selecting the best strategy to improve quality, keeping in view the cost and other aspects

Karahasanovic, Ermin, Lönn, Henrik January 2007 (has links)
The purpose with the thesis was to create a general model that can help companies to take the best decision when it comes to improving the quality of an object. The model was created to solve the problem formulation; How to find the best way to improve the quality of an object, focusing primarily on the relationship between cost and quality but also take other important aspects into consideration. Before the model was created a literature study was performed in ELIN without any useable result. After the literature study was performed quality models like Quality Function Deployment (QFD) and Total Quality Management (TQM) were studied. The study of QFD and TQM showed that they are somewhat complicated and often consider the entire organisation. Simple Quality Model is a smaller model and focuses only at one object at a time. TQM and QFD have however been good inspiration for the creation of SQM. The model was tested in a real-time situation at Saab Communication. Together with Saab Communication we decided to apply SQM to the Swedish defence telenetwork (FTN). In FTN the model was tested at the basic connections. SQM generated 7 different alternatives to improve the dependability in a basic connection. After the application of SQM it showed that alternative 7 was the best alternative. Alternative 7 was to decrease the switch over time. The switch over is today not handled by a special employee and is instead shared among several workers. By employing two new employees there is a possibility to lower the switch over time with 50% down from today’s 60 minutes to 30. To implement this alternative would bring a cost of 5 374 034 SEK and a quality increase of 0,1398955% for the basic connections in the Swedish defence tele-network.
63

A Model for Assessing Cost Effectiveness of Applying Lean Tools

Al-Hamed, Heba, Qiu, Xiaojin January 2007 (has links)
The purpose of this thesis is to develop a model for assessing cost effectiveness of applying lean tools. The model consists of eight phases: it starts by understanding customers' requirements using Voice of Customer (VOC) and Quality Function Deployment (QFD) tools. In phase 2, the current state of plant is assessed using lean profile charts based on Balanced Scorecard (BSC) measures. In phase 3 and phase 4, identification of critical problem(s) and generating of improvement suggestion(s) are performed. Phase 5 provide evaluation of the cost effectiveness of implementing the suggested lean methods based on life cycle cost analysis (LCCA) and phase 6 prefers the right alternative based on multiple criteria decision making (MCDM). In phase 7 the selected alternative is supposed to be implemented and finally the user should monitor and control the process to make sure that the improvement is going as planned. The model was verified successfully using a case study methodology at one Swedish sawmill called Södra Timber in Ramkvilla, one part of Södra group. Results obtained from the study showed that the production and human resources perspectives are the most critical problem areas that need to be improved. They got the lowest scores in the lean profile, 63% and 68%, respectively. Using value stream mapping (VSM) it was found that the non value added (NVA) ratios for the core and side products are 87.4% and 90.4%, respectively. Using the model, three improvement alternatives were suggested and evaluated using LCCA and MCDM. Consequently, implementing 5S got the highest score, second came redesigning the facility layout. However, it was estimated that 4.7 % of NVA for the side product would be reduced by redesigning the facility layout. The recommendations were suggested for the company to improve their performance. The novelty of the thesis is based on the fact that it addresses two main issues related to lean manufacturing: firstly, suggesting lean techniques based on assessment of lean profile that is based on BSC and QFD, and secondly assessing the cost effectiveness of the suggested lean methods based on LCCA and MCDM. This thesis provides a generalized model that enables the decision-maker to know and measure, holistically, the company performance with respect to customer requirements. This will enable the company to analyze the critical problems, suggest solutions, evaluate them and make a cost effective decision. Thus, the company can improve its competitiveness.
64

Solel och solvärme ur LCC-perspektiv för ett passiv-flerbostadshus / PV and solar thermal for a multiple dwelling passive house under a LCC-perspective

Böhme Florén, Simon January 2008 (has links)
This master’s degree project concerns the combination of a multi dwelling passive house with solar energy for the generation of electricity and domestic hot water (DHW). Different alternatives with either solar thermal systems or photovoltaic (PV) systems are compared with two reference alternatives producing DHW from electricity or district heating. The economical comparison uses a life cycle cost (LCC) perspective based on the present value of expenditures for investment, energy and annual operating and maintenance. The energy yields from the solar energy systems were calculated by hand and with simulation software. Calculation and dimensioning of PV systems were carried out with a software called PVSYST. Solar thermal systems were calculated by hand and with the software Winsun Villa Education. Both softwares use hourly weather data for the calculations. The LCCs are lower for the two reference alternatives than for the solar energy alternatives. The reference alternative with district heating generates the lowest LCC. The alternatives with solar thermal energy replace more energy and have significantly lower LCCs than the PV alternatives. The study also shows the importance of using cheap and environmentally friendly backup energy for producing DHW. When aiming for a quantitative energy use target, the DHW-circulation losses ought to be taken into account as these can be extensive.
65

Bridge Management System with Integrated Life Cycle Cost Optimization

Elbehairy, Hatem January 2007 (has links)
In recent years, infrastructure renewal has been a focus of attention in North America and around the world. Municipal and federal authorities are increasingly recognizing the need for life cycle cost analysis of infrastructure projects in order to facilitate proper prioritization and budgeting of maintenance operations. Several reports have highlighted the need to increase budgets with the goal of overcoming the backlog in maintaining infrastructure facilities. This situation is apparent in the case of bridge networks, which are considered vital links in the road network infrastructure. Because of harsh environments and increasing traffic volumes, bridges are deteriorating rapidly, rendering the task of managing this important asset a complex endeavour. While several bridge management systems (BMS) have been developed at the commercial and research level, they still have serious drawbacks, particularly in integrating bridge-level and network-level decisions, and handling extremely large optimization problems. To overcome these problems, this study presents an innovative bridge management framework that considers network-level and bridge-level decisions. The initial formulation of the proposed framework was limited to bridge deck management. The model has unique aspects: a deterioration model that uses optimized Markov chain matrices, a life cycle cost analysis that considers different repair strategies along the planning horizon, and a system that considers constraints, such as budget limits and desirable improvement in network condition. To optimize repair decisions for large networks that mathematical programming optimization are incapable of handling, four state-of-the art evolutionary algorithms are used: Genetic algorithms, shuffled frog leaping, particle swarm, and ant colony. These algorithms have been used to experiment on different problem sizes and formulations in order to determine the best optimization setup for further developments. Based on the experiments using the framework for the bridge deck, an expanded framework is presented that considers multiple bridge elements (ME-BMS) in a much larger formulation that can include thousands of bridges. Experiments were carried out in order to examine the framework’s performance on different numbers of bridges so that system parameters could be set to minimize the degradation in the system performance with the increase in numbers of bridges. The practicality of the ME-BMS was enhanced by the incorporation of two additional models: a user cost model that estimates the benefits gained in terms of the user cost after the repair decisions are implemented, and a work zone user cost model that minimizes user cost in work zones by deciding the optimal work zone strategy (nighttime shifts, weekend shifts, and continuous closure), also, decides on the best traffic control plan that suits the bridge configuration. To verify the ability of the developed ME-BMS to optimize repair decisions on both the network and project levels, a case study obtained from a transportation municipality was employed. Comparisons between the decisions provided by the ME-BMS and the municipality policy for making decisions indicated that the ME-BMS has great potential for optimizing repair decisions for bridge networks and for structuring the planning of the maintenance of transportation systems, thus leading to cost savings and more efficient sustainability of the transportation infrastructure.
66

Improvement to Highway Safety through Network Level Friction Testing and Cost Effective Pavement Maintenance

Abd El Halim, Amir, Omar January 2010 (has links)
Pavements encompass a significant component of the total civil infrastructure investment. In Ontario, the Ministry of Transportation (MTO) is responsible for the maintenance and construction of approximately 39,000 lane-kilometres of highway. In 2004, the province estimated the value of the total highway system at $39 billion dollars. Thus, managing this asset is an important factor to ensure a high level of service to the traveling public. One of the most important indicators of level of service for a road network is safety. Each year, thousands of motorists across North America are involved in motor vehicle collisions, which result in property damage, congestion, delays, injuries and fatalities. The MTO estimated that in 2002, vehicle collisions in Ontario cost nearly $11 billion. Despite the importance of highway safety, it is usually not considered explicitly in the pavement management framework or maintenance analysis. A number of agencies across North America collect skid data to assess the level of safety at both the project and network level (Li et al, 2004). However, a number of transportation agencies still do not collect friction data as part of their regular pavement data collection programs. This is related to both liability concerns and lack of knowledge for how this data can be effectively used to improve safety. The transportation industry generally relies on information such as collision rates, black-spot locations and radius of curvature to evaluate the level of safety of an alignment (Lamm et al., 1999). These are important factors, but the use of complementary skid data in an organized proactive manner would also be beneficial. In preparation for a considered Long Term Area Maintenance Contract, a project was initiated by the MTO to collect network level friction data across three regions in the Province of Ontario. This project represents the first time friction data was collected at the network level in Ontario. In 2006, approximately 1,800 km of the MTO highway network was surveyed as a part of this study. This research utilized the network level skid data along with collision data to examine the relationships and model the impacts of skid resistance on the level of safety. Despite the value of collecting network level skid data, many Canadian transportation agencies still do not collect network level skid data due to the costs and potential liability associated with the collected data. The safety of highway networks are usually assessed using various levels of service indicators such as Wet-to-Dry accident ratio (W/D), surface friction (SN), or the collision rate (CR). This research focused on developing a framework for assessing the level of safety of a highway network in terms of the risk of collision based on pavement surface friction. The developed safety framework can be used by transportation agencies (federal, state, provincial, municipal, etc.) or the private sector to evaluate the safety of their highway networks and to determine the risk or probability of a collision occurring given the level of friction along the pavement section of interest. As a part of the analysis, a number of factors such as Region, Season of the Year, Environmental Conditions, Road Surface Condition, Collision Severity, Visibility and Roadway Location were all investigated. Statistical analysis and modeling were performed to developed relationships which could relate the total number of collisions or the collision rate (CR) to the level of available pavement friction on a highway section. These models were developed using over 1,200 collisions and skid test results from two Regions in the Province of Ontario. Another component of this study examined the Wet-to-Dry accident ratio and compared it to the Skid Number. A number of Transportation Agencies rely on the Wet-to-Dry accident ratio to identify potential locations with poor skid resistance. The results of the comparison further demonstrated the need and importance of collecting network level skid data. Another component of this study was to evaluate the effectiveness of various preservation treatments used within the Long Term Pavement Performance (LTPP) study. In addition, modeling was performed which examined the historical friction trends over time within various environment zones across North America to investigate skid resistance deterioration trends. The results of the analysis demonstrated that commonly used preservation treatments can increase skid resistance and improve safety. The cost effectiveness of implementing preservation and maintenance to increase the level of safety of a highway using Life Cycle Cost Analysis (LCCA) was evaluated. A Decision Making Framework was developed which included the formulation of a Decision Matrix that can be used to assist in selecting a preservation treatment for a given condition. The results of this analysis demonstrate the savings generated by reducing the number of collisions as a result of increasing skid resistance. The results of this research study have demonstrated the importance of network level friction testing and the impact of skid resistance on the level of safety of a highway. A review of the literature did not reveal any protocol or procedures for sampling or minimum test interval requirements for network level skid testing using a locked-wheel tester. Network level friction testing can be characterized as expensive and time-consuming due to the complexity of the test. As a result, any reduction in the required number of test points is a benefit to the transportation agency, private sector (consultants and contractors) and most importantly, the public. An analysis approach was developed and tested that can be used to minimize the number of required test locations along a highway segment using common statistical techniques.
67

Life Cycle Cost Based Model For Successful Maintenance Outsourcing Process Case Study

Fakhoury, Bashar, Alhamed, Heba January 2008 (has links)
The main purpose of this thesis is to develop a new model which helps the decision maker to rationalize outsourcing decisions based on Life Cycle Cost (LCC) analysis and select the appropriate supplier. The model developed consists of four main phases, as well as a pre-evaluating step, which investigate the organization needs and circumstances. Phase I is an evaluation and calculation phase, it assess whether outsourcing is the right policy to be adopted as a competitive advantage from two perspectives; the strategic evaluation of the outsourcing decision, and the cost savings through the life time of the outsourcing process using LCC. Phase II is supplier's selection; it aims to select the preferred supplier using Multiple Criteria Decision Making (MCDM), as well as identifies performance measures to monitor supplier performance. Phase III is maintain and monitor phase, it aims to keep the process and the supplier under continuous revision and assessment. Phase IV is review phase, it aims to identify if a specified monitored parameter is out of control or at critical levels, and identify the causes. This model contribute in covering the lack in the literature by considering LCC in the outsourcing decision making, as well as providing a structured model that concern about the whole process starting by understanding the organizations need and ends by monitoring and review the outsourcing process. The model was validated at one Swedish company, i.e. Kalmar Industries in Ljungby assembly unit, in particular, within the maintenance department. The results of the model validation shows that using LCCA, and risk benefits associated, the preferred alternative is to outsource all the maintenance activities related to ventilation system, these activates involve maintenance personnel, spare parts, and third party to monitor and report the process to authorities. Furthermore, based on LCCA and other suggested criteria and using MCDM, ABB Supplier got the lowest score in MCDM i.e. 36.70% (the lowest LCC along with fulfillment of the qualitative criteria). The main result is that; it is possible to employ LCCA in the maintenance outsourcing process to achieve a strategic model valid for decisions taking over the life length of the process. Consequently, the main recommendation for the case company is to outsource these activities and to transfer it to ABB service supplier.
68

Selecting the best strategy to improve quality, keeping in view the cost and other aspects

Karahasanovic, Ermin, Lönn, Henrik January 2007 (has links)
<p>The purpose with the thesis was to create a general model that can help companies to take the best decision when it comes</p><p>to improving the quality of an object. The model was created to solve the problem formulation; How to find the best way to</p><p>improve the quality of an object, focusing primarily on the relationship between cost and quality but also take other</p><p>important aspects into consideration. Before the model was created a literature study was performed in ELIN without any</p><p>useable result. After the literature study was performed quality models like Quality Function Deployment (QFD) and Total</p><p>Quality Management (TQM) were studied. The study of QFD and TQM showed that they are somewhat complicated and</p><p>often consider the entire organisation. Simple Quality Model is a smaller model and focuses only at one object at a time.</p><p>TQM and QFD have however been good inspiration for the creation of SQM. The model was tested in a real-time situation</p><p>at Saab Communication. Together with Saab Communication we decided to apply SQM to the Swedish defence telenetwork</p><p>(FTN). In FTN the model was tested at the basic connections. SQM generated 7 different alternatives to improve</p><p>the dependability in a basic connection. After the application of SQM it showed that alternative 7 was the best alternative.</p><p>Alternative 7 was to decrease the switch over time. The switch over is today not handled by a special employee and is</p><p>instead shared among several workers. By employing two new employees there is a possibility to lower the switch over time</p><p>with 50% down from today’s 60 minutes to 30. To implement this alternative would bring a cost of 5 374 034 SEK and a</p><p>quality increase of 0,1398955% for the basic connections in the Swedish defence tele-network.</p>
69

Life Cycle Cost Based Model For Successful Maintenance Outsourcing Process Case Study

Fakhoury, Bashar, Alhamed, Heba January 2008 (has links)
<p>The main purpose of this thesis is to develop a new model which helps the decision maker to rationalize outsourcing decisions based on Life Cycle Cost (LCC) analysis and select the appropriate supplier. The model developed consists of four main phases, as well as a pre-evaluating step, which investigate the organization needs and circumstances. Phase I is an evaluation and calculation phase, it assess whether outsourcing is the right policy to be adopted as a competitive advantage from two perspectives; the strategic evaluation of the outsourcing decision, and the cost savings through the life time of the outsourcing process using LCC. Phase II is supplier's selection; it aims to select the preferred supplier using Multiple Criteria Decision Making (MCDM), as well as identifies performance measures to monitor supplier performance. Phase III is maintain and monitor phase, it aims to keep the process and the supplier under continuous revision and assessment. Phase IV is review phase, it aims to identify if a specified monitored parameter is out of control or at critical levels, and identify the causes. This model contribute in covering the lack in the literature by considering LCC in the outsourcing decision making, as well as providing a structured model that concern about the whole process starting by understanding the organizations need and ends by monitoring and review the outsourcing process.</p><p>The model was validated at one Swedish company, i.e. Kalmar Industries in Ljungby assembly unit, in particular, within the maintenance department. The results of the model validation shows that using LCCA, and risk benefits associated, the preferred alternative is to outsource all the maintenance activities related to ventilation system, these activates involve maintenance personnel, spare parts, and third party to monitor and report the process to authorities. Furthermore, based on LCCA and other suggested criteria and using MCDM, ABB Supplier got the lowest score in MCDM i.e. 36.70% (the lowest LCC along with fulfillment of the qualitative criteria).</p><p>The main result is that; it is possible to employ LCCA in the maintenance outsourcing process to achieve a strategic model valid for decisions taking over the life length of the process. Consequently, the main recommendation for the case company is to outsource these activities and to transfer it to ABB service supplier.</p>
70

A Model for Assessing Cost Effectiveness of Applying Lean Tools

Al-Hamed, Heba, Qiu, Xiaojin January 2007 (has links)
<p>The purpose of this thesis is to develop a model for assessing cost effectiveness of applying lean tools. The</p><p>model consists of eight phases: it starts by understanding customers' requirements using Voice of Customer</p><p>(VOC) and Quality Function Deployment (QFD) tools. In phase 2, the current state of plant is assessed</p><p>using lean profile charts based on Balanced Scorecard (BSC) measures. In phase 3 and phase 4,</p><p>identification of critical problem(s) and generating of improvement suggestion(s) are performed. Phase 5</p><p>provide evaluation of the cost effectiveness of implementing the suggested lean methods based on life cycle</p><p>cost analysis (LCCA) and phase 6 prefers the right alternative based on multiple criteria decision making</p><p>(MCDM). In phase 7 the selected alternative is supposed to be implemented and finally the user should</p><p>monitor and control the process to make sure that the improvement is going as planned. The model was</p><p>verified successfully using a case study methodology at one Swedish sawmill called Södra Timber in</p><p>Ramkvilla, one part of Södra group. Results obtained from the study showed that the production and human</p><p>resources perspectives are the most critical problem areas that need to be improved. They got the lowest</p><p>scores in the lean profile, 63% and 68%, respectively. Using value stream mapping (VSM) it was found that</p><p>the non value added (NVA) ratios for the core and side products are 87.4% and 90.4%, respectively. Using</p><p>the model, three improvement alternatives were suggested and evaluated using LCCA and MCDM.</p><p>Consequently, implementing 5S got the highest score, second came redesigning the facility layout.</p><p>However, it was estimated that 4.7 % of NVA for the side product would be reduced by redesigning the</p><p>facility layout. The recommendations were suggested for the company to improve their performance. The</p><p>novelty of the thesis is based on the fact that it addresses two main issues related to lean manufacturing:</p><p>firstly, suggesting lean techniques based on assessment of lean profile that is based on BSC and QFD, and</p><p>secondly assessing the cost effectiveness of the suggested lean methods based on LCCA and MCDM. This</p><p>thesis provides a generalized model that enables the decision-maker to know and measure, holistically, the</p><p>company performance with respect to customer requirements. This will enable the company to analyze the</p><p>critical problems, suggest solutions, evaluate them and make a cost effective decision. Thus, the company</p><p>can improve its competitiveness.</p>

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