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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.
341

Prefabricerade innerväggar : Kostnad- och tidseffektivitet för lätta prefabricerade innerväggar / Prefabricated interior walls : Cost and time efficiency for lightweight prefabricated interior walls

Friberg, Martin, Ringtun, Eric January 2015 (has links)
Kostnad och tid är två parametrar som går hand i hand i näst intill alla sammanhang, inte minst i byggbranschen. Pressade tidsplaner och snäva budgetar kräver noggrannhet och effektivitet genom samtliga skeden i byggprocessen. Framför allt är en kortare byggtid av stor vikt, som ett resultat av det har det industriella byggandet fått en alltmer betydande roll. Syftet med denna rapport är att undersöka lönsamheten vid användandet av prefabricerade element gentemot konventionell platsbyggning. Arbetet har avgränsats till att undersöka ett enskilt område, nämligen lätta innerväggar. Rapporten har gjorts i samarbete med Peab AB och den har utförts på deras pågående projekt, köpcentrumet Mall of Scandinavia i Arenastaden, Solna. De två byggmetoderna har jämförts med avseende på tid och ekonomi. Vidare har de prefabricerade väggelelementens för- och nackdelar samt alternativa användningsområden undersökts. De prefabricerade innerväggarna som används i projektet tillverkas av företaget Elementum Eco AB i Bollebygd. Monteringen av väggelementen sker med hjälp av en modifierad gaffeltruck, vilket är ovanligt. Metoden kräver endast tre arbetare och medför en avsevärt kortare monteringstid jämfört med platsbyggda innerväggar. Metoden är ny för Peab och det är andra gången som de valt att använda sig av den. Det var vid ett tidigare projekt i Tanums kommun, då köpcentrumet Tanum shoppingcenter byggdes, som metoden introducerades för företaget. Efter färdigställandet var erfarenheterna av väggelementen positiva. Man ansåg sig ha vunnit både tids- och kostnadsmässigt och valde därför att bepröva metoden ytterligare en gång. Jämförelsen mellan de båda byggmetoderna har gjorts på två väggar med samma förutsättningar vad gäller dimension och arbetskraft. Fördjupade intervjuer som huvudmetod, egenhändigt utförda inspektioner och litteraturstudie har föranlett resultat i rapport. Resultatet av detta arbete visar att kostnads- och tidseffektiviteten ökar med en faktor på upp till närmare nio gånger, genom val av prefabricering som metod jämfört med konventionell platsbyggning som metod. Flera fördelar påvisas även inom områden som arbetsmiljö och miljöpåverkan. / Cost and time are two parameters that affect one another no matter what the context is, not least in the building industry. Both time schedules and budgets are pushed to the limit, therefore accuracy and efficiency needs to be considered through all stages of the building process. A shorter construction time is of vital importance and as a result of that, industrial building methods has taken a more significant part in the business. The purpose of this report was to investigate the profitability by using prefabricated panels instead of conventional building methods. Due to a given timeframe the investigation has been defined to focus on one special field, namely light prefabricated interior walls. The report was developed in collaboration with Peab AB and the work has been done on their ongoing project Mall of Scandinavia in Arenastaden, Solna. The two construction methods have been compared with respect to time and finances. Furthermore, the prefabricated panels advantages and disadvantages as well as alternative uses have been studied. The prefabricated interior walls, used in the project, are produced by Elementum Eco AB in Bollebygd. The walls are mounted by means of a modified forklift truck, which is somewhat unique. The mounting process requires only three workers and results in a considerably shorter assembly time compared to site-built interior walls. It is a new method and it is used by Peab for the second time. The company was introduced to the method at an earlier project in Tanum, when Tanum shopping centre was established. The over all experience turned out positive and once completed, both time and cost was considered to have been saved. Peab therefore chose to use the method once more. The comparison between the two methods of construction has been made on two walls with similar conditions in terms of size and manpower. The result of this report shows that both time and cost efficiency can increase nearly nine times by choosing prefabricated interior walls compared to conventional site-built ones. Furthermore, benefits in areas such as environmental impact and work environment are shown as well.
342

Feasibility Analysis of a Fiber Reinforced Polymer Bridge

Murphy, Neil January 2013 (has links)
When implementing a bridge design proposal, it is common that several alternatives be considered, each with a different material of construction. Traditional building materials used for the construction of bridges have mainly been concrete, steel, timber or aluminium. With all these materials options, maintenance and replacement costs throughout the lifespan of a bridge make up for a large proportion of their total life cycle costs. Fiber Reinforced Polymer (FRP) provides a new viable construction material, which can be implemented in bridge construction. This plastic based material has favourable material properties such a very high strength to weight ratio, high corrosion resistance and durability, as well as very low maintenance costs over its lifetime. In the feasibility analysis, a case study of an existing FRP deck bridge was taken and examined in three aspects: structural, economic and environmental. The bridge was also redesigned with a concrete deck solution, to provide a comparison to a conventional construction material. The results were found, in general to be favourable towards the FRP solution. From the structural analysis savings on deflection, support reactions and superstructure stresses were outputted. Economically, the composite material was found to have a substantial higher initial cost but much lower periodic maintenance costs than the concrete option. Finally the FRP bridge option displayed a lower construction time for the superstructure, at one third of that of concrete and an overall lower environmental impact, based on material production and the overall bridge construction process.
343

Rekommenderade Livscykelplaner för övergångskonstruktioner : En utvärdering av BaTMan data / Recommended Life-Cycle Plans for bridge expansion joints : An evaluation of BaTMan data

Srba, Martin January 2016 (has links)
Studien syftar till att ta fram rekommenderade livscykelplaner för övergångskonstruktioner för att i framtiden möjliggöra säkrare livscykelkostnadsanalyser. Nedbrytningen av övergångskonstruktioner kan grovt delas upp i två kategorier, användarrelaterad nedbrytning samt nedbrytning associerat med rådande klimatförhållanden. I studien har årsdygnstrafiken och klimatzonernas påverkan på övergångskonstruktionen studerats genom utvärdering av historiskt utförda åtgärder kopplade till Trafikverkets broförvaltningssystem BaTMan. Regressionsanalyser och överlevnadsanalyser utfördes för de vanligaste åtgärderna. Resultaten visar att utbyte av tätprofil samt övergångskonstruktion är de åtgärder som förekommer allra mest och sker i genomsnitt efter 25 respektive 33 år. Från analyserna kunde utläsas att trafikintensiteten är en faktor som direkt påverkar nedbrytningen och således reparation och utbyte av övergångskonstruktion, troligt är även att tung trafik står för en stor del av nedbrytningen. Även klimatet verkar ha en påverkan på både övergångskonstruktionens och tätprofilens livslängd. Baserat på resultaten rekommenderas tre livscykelplaner, livscykelplanerna kan användas som underlag i framtida livscykelberäkningar. De kan även användas som stöd för förvaltare vid uppbyggnad av strategier under förvaltningsfasen. / This study aims to develop recommended Life-Cycle Plans for bridge expansion joints which in the future can be used for Life-Cycle Cost analysis to achieve a higher degree of certainty. The degradation of expansion joints can be roughly divided into two categories, user-related degradation and degradation due to climatic conditions. In the study, the influence of annual average daily traffic and climate zones on the expansion joint will be studied by evaluating historically conducted maintenance actions related to the Swedish Transport Administrations (Trafikverket) bridge management system BaTMan. Regression analysis and survival analyzes were performed for the most common actions. The results show that replacement of the strip seal and the expansion joint is the most commonly performed maintenance measures and occurs on average after 25 and 33 years. From the analyzes it was deduced that the traffic intensity is a factor that directly affects the degradation and therefore also the repair and replacement of the expansion joint, likely is also that a large part of the degradation is due to the wear of heavy vehicles. The climate also seems to have an impact on the lifetime of the expansion joint as well as the strip seal. Based on the results, three Life-Cycle Plans was recommended. These Life-Cycle Plans can be used for future Life-Cycle Cost calculations but also to support bridge managers when comparing different maintenance strategies during the operational phase.
344

Life Cycle Costing in Road Planning and Management : A Case Study on Collision-free Roads

Wennström, Jonas January 2014 (has links)
Construction of infrastructure does not only mean large capital investments but also future costs to operate and maintain these assets. Decision making in planning and design of roads will impact the need of future operation and maintenance activities. Additionally, infrastructure management is often under increasing pressure of aging structures, limited budgets and increased demands from public which require transparency in the decision making. Life cycle costing is a methodology that takes into account costs throughout an asset’s life cycle including investment, operation, maintenance and disposal. Despite the methodology’s existence for more than 40 years, the practical application is often reported to be scarce in both private and public sectors. Implementation in road planning and management means a high complexity where the life cycle costing can to be applied from early planning, design, construction and management in which all influence life cycle cost. Life cycle costing can also be applied in many different ways, level of detail and for different type of studies. For effective implementation of life cycle costing in road planning, design and management, different considerations need to be understood. In this thesis the application of life cycle costing has been studied through case study research. The main case selected was an investment to convert a single carriageway road to a, so called, sparse collision-free road. Through widening and separation between driving directions the traffic safety is significantly improved. However, in recent years increased operation and maintenance costs have been associated with the road type. Especially concerns regarding increased road user cost during road works have been expressed. This case was examined in two case studies from different perspectives. The first one was to study the implications on project appraisal and the second one examined the possibility to optimise pavement design. Results from cost benefit analyses based on established road appraisal techniques indicated that operation and maintenance related costs had limited impact on profitability. The second study also indicated that future cost can be influenced differently depending on criteria for optimal alternative. Based on economic analyses using established techniques, increased operation and maintenance liabilities appear to be of limited concern, in contrary to the perception. In future research this need to be set in context of road management with refined analysis in order to study implications for future management. / <p>QC 20141028</p>
345

Investigating the replacement of old passenger cars with modern less emission intensive cars in Sweden using Total Cost of Ownership approach

Zafar, Shahab January 2022 (has links)
Purpose. In Sweden, private commuting accounts for two third of total transportation emissions and 21% of the country’s total. To become net-zero by 2045, Sweden plans to have 2 million electric cars on the roads by 2030. Whereas with current pace, there will be 1 million electric cars by the end of the decade. Cars registered before 2016 (referred to as old cars in the study) make up nearly half of the Swedish car fleet. Thus, replacing the old emission intensive cars with the modern lower or zero emission cars will catalyze the decarbonization of Swedish transport sector. Therefore, the purpose of this study is to probe if it is economical to keep using an old car in the future or to replace it with a new one. Methods. This study first compares the next 13-year Total Cost of Ownership (TCO) of old V70 (having current milage 200,000 km) with that of new replacement cars. The (selected) replacement are the most registered modern-day cars in Sweden by fuel type having same size as that of V70: V60 (ICE), V60 (PHEV) and Tesla Model 3 (BEV). Moreover, using TCO framework, the study also estimates if the replacement is more economical now or sometime in the future with either new replacement cars or their (4-year) used models. Results. The results show that for next 13-years in Sweden, it is more economical to replace the old V70 with any of the replacement cars. However, Tesla Model 3 is the cheapest option among the new cars and V60 (PHEV) among the used cars. Overall, it is more economical to replace with a used car. In addition, the replacement is most economical if done immediately (in 2022) and gets more expensive by each year of delay- because the owner will have to incur relatively higher V70 costs (vis-à-vis the replacement cars) for an additional year. Sensitivity analysis shows that with higher current salvage value, a V70 gets more expensive to own in next 13 years (due to higher depreciation) whereas the replacement becomes cheaper (utilizing higher salvage value to buy the replacement car). Discussion. The study can be expanded to suggest economical and emission efficient replacement options for other old cars to accelerate the decarbonization of Swedish private transport sector. Furthermore, this study was done in collaboration with Mekonomen Group to see the financial worth of old ICE car replacement by its customers. The study results reinforce the group’s diversification strategy from ICE cars-oriented business model to BEVs as the top focus. Finally, this study is based on the assumption that the total number of cars in Sweden will not increase in future- the old gets replaced by the new. Therefore, from a holistic perspective, the study discusses that a sustainable transportation model should move away from private ownership towards shared mobility to avoid the rebound effects of technological efficiency that increase the overall resource consumption.
346

Höghållfast stål : Optimerat materialutnyttjande i byggnadsstommar / High strength structural steel : Optimal use of material

Lagerstedt, Camilla, Fors Zavalis, Malin January 2013 (has links)
I detta examensarbete utförs en jämförelse av HSQ-balkar och VKR- pelare i hållfasthetsklass S355 respektive S460. I arbetet dimensioneras profiler anpassade efter studerade fiktiva konstruktioner och ställs emot varandra. Syftet är att optimera profilerna och effektivisera stålanvändningen. Förhoppningen är att en applicering av höghållfast stål i vanliga konstruktioner medför en reducerad stålmängd. Är minskningen tillräckligt stor bidrar denna i sin tur till en mindre miljöpåverkan samt kostnadseffektiva dimensioneringslösningar. Två olika byggnadsstommar utförda i stål med sträckgränsen 355 respektive 460 MPa undersöks. Huvudkonstruktionen studeras i delalternativ beroende på en variation av upplagsfall och stålklass vilket påverkar dimensioneringen av profilerna. Resultaten används för att göra en miljö- och kostnadsanalys. Rapporten visar blandade resultat. Det finns besparingar att göra men inte i alla avseenden. Miljöanalysen visar att koldioxidutsläppet minskar i de alternativ där stålmängden reducerats. En prisuppskattning av de framtagna profilerna visar att inga kostnadsbesparingar kan göras då alla balkar och pelare i den studerade konstruktionen byts ut till stål med en högre hållfasthetsklass. I de enskilda fall där materialbesparingen är över 10 % kan kostnadsbesparingar göras. / The thesis is a comparison of HSQ-beams and VKR-columns of strength grade S355 and S460. In this study, profiles designed for two different fictional construction frames are compared to each other. The aim is to optimize the profiles and streamline the steel use. Hopefully the usage of high-strength steel in ordinary structures results in a reduced amount of steel. If the decrease is sufficiently large it contributes to a reduced environmental impact and cost effective solutions. Two separate building frames made in both steel with yield strength of 355 and 460 MPa are examined. The main structure is studied in sub-options depending on a variety of support case and steel grade which affects the design of the profiles. The results are used to analyze their impact on costs and environment. The report shows mixed results. There are savings to be made but not in all respects. Environmental analysis shows that carbon dioxide emissions decrease in the options where the steel amount is reduced. A price estimation of the profiles show that no savings can be made when the entire studied structure is upgraded to a high strength steel. However, cost savings can be made in individual cases where the material savings is 10 % higher.
347

The Cost of Algorithmic decisions : A Systematic Literature Review

Erhard, Annalena January 2021 (has links)
Decisions have been automated since the early days. Ever since the rise of AI, ML and DataAnalytics, algorithmic decision-making has experienced a boom time. Nowadays, using AI withina company is said to be critical to the success of a company. Considering the point that it can bequite costly to develop AI/ ML and integrating it into decision-making, it is striking how littleresearch was put into the identification and analysis of its cost drivers by now. This thesis is acontribution to raise and the awareness of possible cost drivers to algorithmic decisions. Thetopic was divided in two subgroups. That is solely algorithms and hybrid decision-making. Asystematic literature review was conducted to create a theoretical base for further research. Thecost drivers for algorithms to make decisions without human interaction, the identified costdrivers identified can be found at Data Storage (including initial, floor rent, energy, service,disposal, and environmental costs), Data Processing, Transferring and Migrating. Additionally,social costs and the ones related to fairness as well as the ones related to algorithms themselves(Implementation and Design, Execution and Maintenance) could be found. Business Intelligenceused for decision making raises costs in Data quality, Update delays of cloud systems, Personneland Personnel training, Hardware, Software, Maintenance and Data Storage. Moreover, it isimportant to say that the recurrence of some costs was detected. Further research should go inthe direction of applicability of the theoretical costs in practice.
348

Sistema de atención de requerimientos para una empresa de software contable utilizando machine learning para la predicción de costos / Requirements attention system for an accounting software company using machine learning for cost prediction

Montero León, Carlos E., Villavicencio Mendivil, Fabio Alonso 18 May 2019 (has links)
El presente trabajo se centra en desarrollar un sistema para la atención de requerimientos con el fin de gestionar y evaluar con precisión los requerimientos que se generan a diario en una empresa que desarrolla software contable. Asimismo, reducir la brecha del costo, que normalmente se realiza por experiencia del personal, con la ayuda de la tecnología machine learning, la cual ayudará a la predicción del costo del requerimiento. Con el fin de conseguir el éxito, este trabajo se ha estructurado en los siguientes capítulos: En el capítulo 1, se expondrá el marco teórico, también se presentará a la organización objetivo y su situación problemática. En el capítulo 2, se presentará los objetivos del proyecto, junto a sus respectivos indicadores. Se expondrá los distintos beneficios que traerá consigo el proyecto. En el capítulo 3, se desarrollará todo el modelado de negocio, actores, trabajadores y diagrama de casos de uso del negocio. En el capítulo 4, se abordarán los temas de modelado de los casos de uso del sistema, con sus respectivos actores, paquetes y diagramas; por último, la especificación detallada de casos de uso del sistema del ciclo cero y el modelo conceptual. En el capítulo 5, donde se definirá la arquitectura de software y se plantearán las metas, restricciones, mecanismos y vistas (lógica, implementación, despliegue) de la arquitectura. En el capítulo 6, se definirá la política de calidad de software, los objetivos, métricas y las pruebas del software. En el capítulo 7, se desarrollará la construcción del núcleo software, indicando sus patrones de solución y modelo de datos. En el capítulo 8, se presentará a los principales interesados, EDT, cronograma y riesgos del proyecto. / The present work focuses on developing a system to meet requirements in order to accurately manage and evaluate the requirements that are generated daily in a company that develops accounting software. Likewise, reduce the cost gap, which is normally carried out by the experience of the staff, with the help of machine learning technology, which will help to predict the cost of the requirement. In order to achieve success, this work has been structured in the following chapters: In Chapter 1, the theoretical framework will be covering the objective organization and its current problems, a diagnose of the situation. In Chapter 2, the objectives of the project will be presented, along with their respective indicators. The different benefits that the project will bring will be exposed. In Chapter 3, we will develop all the business modeling, actors, workers, and diagrams. In Chapter 4, the topics of modeling the use cases of the system will be addressed, with their respective actors, packages and diagrams, finally, the detailed specification of system use case of the zero cycle and the conceptual model. In Chapter 5, where the software architecture will be defined, where the goals, restrictions, mechanisms and views of the architecture are presented. Chapter 6 will define the software quality policy, objectives, metrics, and testing of the software. In Chapter 7, the construction of the software kernel will be developed, indicating its solution patterns and data model. In Chapter 8, the main stakeholders, WBS, project schedule and risks will be presented. / Tesis
349

Controlling ve stavebním podniku / Controlling in the Construction Company

Jančová, Edita Unknown Date (has links)
The theme of this thesis is controlling in the construction company. The theoretical part is focused on the management of a contruction company, controlling and its tools. In the practical part, the current state of the selected construction company is analyzed and a proposal for the introduction of controlling in the company is made. Subsequently, the future benefits of this proposal, the possible risks of the proposed measures, the timetable and the eastimated costs are presented.
350

Multi-Hazard Lifecycle Methods for Aging Structures and Infrastructure Systems

Fereshtehnejad, SeyedEhsan January 2018 (has links)
No description available.

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