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The doctoral thesis is dedicated to cost estimation analysis of mass and lean logistics system productivity including their comparison. The main focus is on methodology of cost estimation of currently used supply chains. The methodological part encompasses contemporary knowledge of productivity, philosophical background of Logistics and identification of today market conditions emphasizing the importance of knowledge as a competitive advantage. The logistics value and waste are identified as a critical aspect in analysing of productivity of current logistics system. Regarding the scope of today knowledge analysis, experimental questions and hypothesis related to utilisation and measuring efficiency lean logistics principals and tools are defined. Based on the hypothesis verification, new theory and methodology of productivity cost estimation in mass and lean logistics system applicable not only in automotive industry are established. The doctoral thesis reveals new spheres of logistics theory, scientifical research in the area of logistics systems productivity. The case of automotive supply chain supports the utilisation of proposed theory and methodology in practice.

Performance-based maintenance contracts differ significantly from material and method-based contracts that have been traditionally used to maintain roads. Road agencies around the world have moved towards a performance-based contract approach because it offers several advantages like cost saving, better budgeting certainty, better customer satisfaction with better road services and conditions. Payments for the maintenance of road are explicitly linked to the contractor successfully meeting certain clearly defined minimum performance indicators in these contracts. Quantitative evaluation of the cost of performance-based contracts has several difficulties due to the complexity of the pavement deterioration process. Based on a probabilistic analysis of failures of achieving multiple performance criteria over the length of the contract period, an effort has been made to develop a model that is capable of estimating the cost of these performance-based contracts. One of the essential functions of such model is to predict performance of the pavement as accurately as possible. Prediction of future degradation of pavement is done using Markov Chain Process, which requires estimating transition probabilities from previous deterioration rate for similar pavements. Transition probabilities were derived using historical pavement condition rating data, both for predicting pavement deterioration when there is no maintenance, and for predicting pavement improvement when maintenance activities are performed. A methodological framework has been developed to estimate the cost of maintaining road based on multiple performance criteria such as crack, rut and, roughness. The application of the developed model has been demonstrated via a real case study of Miami Dade Expressways (MDX) using pavement condition rating data from Florida Department of Transportation (FDOT) for a typical performance-based asphalt pavement maintenance contract. Results indicated that the pavement performance model developed could predict the pavement deterioration quite accurately. Sensitivity analysis performed shows that the model is very responsive to even slight changes in pavement deterioration rate and performance constraints. It is expected that the use of this model will assist the highway agencies and contractors in arriving at a fair contract value for executing long term performance-based pavement maintenance works.

Byggbranschen halkar efter i digitalisering om den jämförs med andra tillverkande industrier.Byggkostnaderna är höga och effektiviseringen går bakåt samtidigt som det blir mer och meratt göra. Vad går det att göra för att branschen ska följa med i den digitala utvecklingen ochvart står den idag?I skolan är arbetet i datorprogram vanligtvis det självklara valet för en mer digital arbetsprocess,men på byggföretagen ser det annorlunda ut. Alltifrån att mäta med skalstock från ritningaroch summera i Excel till att mängda från 3D-modeller.Det finns tidigare rapporter som påvisar att arbetet med BIM i företag ger positiva effekteroch att det egentligen bara är att börja arbeta med det direkt för att se resultat. Men varför börjarinte fler med BIM och vilken kvalitet håller modellerna idag? De arbeten som studerats gerresultatet av att mängdavtagning från en 3D-modell stämmer mellan metoderna traditionelloch modellbaserad mängdavtagning. I de fall där det undersökts mellan utfallen har det vanligtvisgjorts en avgränsning att bara kolla på en del av byggdelarna i en byggnad och intehela kalkylen. Ett första steg i implementeringen av BIM är enligt författaren att en mängdavtagninggår att utföra på modellen för ett projekt. Vilka mängder går det att exportera ur en3D-modell som stämmer överens med mängder från en traditionell mängdavtagning? Går detatt göra en korrekt mängdavtagning med modeller?För att detta examensarbete ska bidra med ny kunskap har steg ett varit att kartlägga hurbyggföretaget arbetar idag. Steg två har varit att utvärdera 3D-modeller från sex projekt ochjämföra med kalkylatorns kalkyl från anbuds- och projekteringsskedet. I arbetet har hela kalkylenoch 3D-modellen använts, inga komponenter eller byggdelar har avgränsats bort. Ettsista steg har varit att utifrån kravspecifikationer mot arkitekt utvärderat hur de framtagna kravenfrån SBUF projektet Detaljeringsnivå i BIM fungerar i de sex projekten som utvärderat idetta arbete. Målet är att ge en rekommendation kring kravställning för 3D-modeler och förslagpå hur företag kan bli mer digitala.Resultatet från kartläggningen över hur de arbetar med 3D-modeller för mängdavtagning idagvisar att det inte används. Det som används idag är skalstock med utskrivna ritningar, Excel,Bluebeam och kalkyleringsprogrammet Bidcon. Av de anställda i företaget är de flesta intresseradeav BIM men att ta steget till att implementera det är individuellt och det finns några individersom hade uppskattat att arbeta med det. I framtiden tror författaren att en implementeringav krav på konsulter och att modulen Bidcon BIM är en bra start på en mer digital arbetsplats.Utvärderingen av 3D-modellerna gav tre summerade resultat. Mängderna från den modellbaseradmängdavtagningen har jämförts mot kalkylatorns kalkyl. Skillnaden mellan utfallenvalde författaren till att högst få vara 10 procent för att anses vara ett godkänt resultat. Detsom låg innanför marginalen och som gick att hitta i modellen och stämde överens med kalkylatornsmängd är 47 procent. Det som inte gick att identifiera i 3D-modellen är 33 procent.Det som gick att identifiera men där skillnaden var större än 10 procent är 21 procent.När det kommer till kravställningen på konsulterna utifrån SBUF-projektet är det en bra startmen det går att göra lite mindre revideringar för att få den mer lättjobbad. Det beror på hur företagetarbetar idag. Ett exempel är att ta bort kravet gällande BSAB-koder och istället läggavikt på konsekvent namngivning av familj och typ av byggdelarna.

When considering the addition of a mobile presentation channel to an existing web-based application, a key question that has to be answered even before development begins is how the mobile channel's characteristics will impact the user experience and the cost of using the application. If either of these factors is outside acceptable limits, economical considerations may forbid adding the channels, even if it would be feasible from a purely technical perspective. Both of these factors depend considerably on two metrics: The time required to transmit data over the mobile network, and the volume transmitted. The PETTICOAT method presented in this paper uses the dialog flow model and web server log files of an existing application to identify typical interaction sequences and to compile volume statistics, which are then run through a tool that simulates the volume and time that would be incurred by executing the interaction sequences on a mobile channel. From the simulated volume and time data, we can then calculate the cost of accessing the application on a mobile channel, and derive suitable approaches for optimizing cost and response times.

When considering the addition of a mobile presentation channel to an existing web-based application, a key question that has to be answered even before development begins is how the mobile channel’s characteristics will impact the user experience and the cost of using the application. If either of these factors is outside acceptable limits, economical considerations may forbid adding the channels, even if it would be feasible from a purely technical perspective. Both of these factors depend considerably on two metrics: The time required to transmit data over the mobile network, and the volume transmitted. The PETTICOAT method presented in this paper uses the dialog flow model and web server log files of an existing application to identify typical interaction sequences and to compile volume statistics, which are then run through a tool that simulates the volume and time that would be incurred by executing the interaction sequences on a mobile channel. From the simulated volume and time data, we can then calculate the cost of accessing the application on a mobile channel.

Thermo-economic modeling refers to the process of estimating the cost and performance of a power plant using cost oriented equations and reference data. In this thesis the fundamentals of cost and performance modeling as well as sensitivity analysis is researched and applied to an existing model in the field of concentrated solar power. The thesis aims to isolate the sources of possible errors and presents comprehensible methods of minimizing the sensitivity these give rise to. The extensive literature study provides the knowledge and methodologies necessary to perform an evaluation of a computer model and these methodologies are applied to the tool DYESOPT developed at the Royal Institute of Technology.   The evaluation highlights the importance of reliable references of operational solar power plants and also the current lack of such data. A particular area suffering from this is the cost estimation, which includes assumptions and requires future revisions. The sensitivity analysis methodologies one-at-a-time and the sensitivity index are used to locate the areas where extra care must be taken in order to minimize error as well as provide an understanding of the internal correlation of critical inputs.   The results show that the accuracy of the model is dominated by three inputs: solar multiple, tower height and storage time, and that certain intervals and combinations of these decide the overall error of the model. By isolating the intervals in which the sensitivity is at its minimum the model error can be roughly quantified with a class system using standard error intervals. For a model such as DYESOPT a minimum error of 20 to 30 percent is a reasonable assumption.

About 75% of the total product cost is determined in the early design phase, which means that the possibilities to affect costs are relatively small when the design phase is completed. For companies, it is therefore vital to conduct reliable cost estimates in the early design phase, when selecting between different design choices. When conducting a cost estimate there are many uncertainties. The aim with this study is therefore to explore how uncertainties regarding product cost can be considered when estimating product cost and how expert’s knowledge can be integrated within cost estimation. A case study has been conducted within the aerospace industry at the company GKN Aerospace Sweden (GAS) in Trollhättan, from which a model to estimate product cost has been developed. The model is developed for space turbines, but can with modifications be used for other products. Space turbines are highly advanced products, produced in small batches with complex manufacturing processes and high costs. Because of the heavy capital investment, long lead times and high risks, cost estimates become very important, which made GAS suitable for the case study. The new cost estimation model (NCEM) developed is a combination between intuitive, analogical and analytical cost estimation techniques. Product cost at GAS is built up by the following cost elements; raw material, purchased parts, material surcharge, manufacturing cost, manufacturing surcharge, outsourced operations, method support, delivery cost, warranty and scrap, which are studied more in depth. The material cost is estimated based on historical data and a list of previous purchased alloys is created. The manufacturing cost is determined more in detail where the cost for each operation is estimated, based on operation time, amount of removed material or welding speed. The method support cost is estimated based on a study of an internal prognosis where the amount of time from each discipline needed to support the product is determined. Included in the NCEM is also a risk assessment. The main insights from this study is that transparency is vital when estimating product cost. It is important to state what assumptions that have been made. Breaking down the product cost into smaller units and create awareness about the cost drivers will identify risks and reduce uncertainness. Experts possess a great deal of knowledge about cost drivers and should be integrated when estimating product cost.

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The complexity of software development projects makes estimation and management very difficult. There is a need for improved cost estimation methods and new models of lifecycle processes other than the common waterfall process. This work has developed a new simulation model of the spiral development lifecycle as well as an approach for using simulation for cost and schedule estimation. The goal is to provide a tool that can analyze the effects of a spiral development process as well as a tool that illustrates the difficulties management faces in forecasting budgets at the beginning of a project which may encourage more realistic approaches to budgetary planning. A new discrete event process model of the incremental spiral development lifecycle approach was developed in order to analyze the effects this development approach has on the estimation process as well as cost and schedule for a project. The input data for the key variables of size, productivity, and defect injection rates in the model was based on analysis of Software Engineering Laboratory data and provided for analysis of the effects of uncertainty in early project estimates. The benefits of combining a separate system dynamics model with a discrete event process models was demonstrated as was the effects of turnover on the cost and schedule for a project. This work includes a major case study of a cancelled NASA software development project that experienced cost and schedule problems throughout its history. Analysis was performed using stochastic simulation with derived probability distributions for key software development factors. A system dynamics model of human resource issues was also combined with the process model to more thoroughly analyze the effects of turnover on a project. This research has demonstrated the benefits of using a simulation model when estimating to allow for more realistic budget and schedule determination including an interval estimate to help focus on the uncertainty of early estimates.