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- Brunes, Fredrik, 1968-
(författare)
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Essays on behavioural economics and cost overuns
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation consists of five essays, four on cost overruns and one on behavioral economics witha focus on real estate investments. The main aim of the thesis was to answer the questions:• Is it common with cost overruns in infrastructure projects?• What explains the cost overruns?• What can be done to prevent cost overruns?This thesis contributes to the current state of knowledge within the field:• It is yet another evidence that cost overruns are a significant problem.• Optimism bias is an explanation of cost overruns. However, the thesis adds, by Article two, arationality explanation.• Dismisses in part the Successive method as a tool to reduce cost overruns.• Provide recommendations on how action against cost overruns can be systematized.The first article, which is a result of my Licentiate thesis deals with real estate investments and the fact that investors sometimes are influenced by behavioral aspects that make them deviate fromwhat is rational. The result is some what uncertain but shows that investors in these cases were influenced by myopic behaviour.The second article deals with cost overruns and rationality. The question is whether it can be rational in a procurement, using a unit‐price contract, to expect cost overruns. The result shows that it is possible in situations where the decision maker has to take renegotiation costs and monitoring costs into account.The third article examines how well the successive method can pvents cost overruns. Established results in research on cost overruns indicated that strategic factors, psychological factors (optimism bias) and technical factors are important to explain cost overruns. The review suggests that the Successive method has limitations as a method to reduce cost overruns because it cannot deal with strategic and psychological factors.The fourth article focus on why cost overruns incurred. The article presents a new framework based on microeconomic cost theory and also results based on a survey to project managers in infrastructure projects, suggesting that cost overruns are common and that cost overrun mainly aredue to the optimism bias.The issue addressed in the fifth article is what can be done to prevent cost overruns. The conclusion, based on questionnaire survey and literature review, suggests that a variety of policy measures are needed at different levels such as (1): Organizational macrostructure where e.g. cost overruns in a project in one region leads to less projects in that region.(2) Organizational quality: improved transparency within organizations to see where and when cost overruns occur. (3) Organizational processes: e.g. the use of external reviewers.
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| 2. |
- Edmark, Lennart, 1954-
(författare)
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Reducing Atelectasis during General Anaesthesia – the Importance of Oxygen Concentration, End-Expiratory Pressure and Patient Factors : A Clinical Study Exploring the Prevention of Atelectasis in Adults
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: The use of pure oxygen during preoxygenation and induction of general anaesthesia is a major cause of atelectasis. The interaction between reduced lung volume, resulting in airway closure, and varying inspiratory fractions of oxygen (FIO2) in determining the risk of developing atelectasis is still obscure.Methods: In this thesis, computed tomography (in studies I and II during anaesthesia, in studies III and IV postoperatively) was used to investigate the area of atelectasis in relation to FIO2 and varying levels of continuous positive airway pressure (CPAP) or positive end-expiratory pressure (PEEP).Study I investigated the short-term influence of reducing FIO2 during preoxygenation and induction of general anaesthesia, and the time to hypoxia during apnoea.Study II focused on the long-term effect of an FIO2 of 0.8 for preoxygenation.Study III applied CPAP/PEEP with an FIO2 of 1.0 or 0.8 for pre- and postoxygenation until extubation. After extubation, CPAP with an FIO2 of 0.3 was applied before the end of mask ventilation.Study IV compared two groups given CPAP/PEEP during anaesthesia and an FIO2 of 1.0 or 0.3 during postoxygenation, but without CPAP after extubation.Results: Study I showed a reduction in atelectasis with an FIO2 of 0.8 or 0.6, compared with 1.0, but the time to hypoxia decreased. In study II, atelectasis evolved gradually after preoxygenation. In study III, atelectasis was reduced with an FIO2 of 1.0 and CPAP/PEEP compared with an FIO2 of 1.0 without CPAP/PEEP. The intervention failed in the group given an FIO2 of 0.8, this group had more smokers. Atelectasis and age were correlated. In study IV, no difference was found between the groups. Post hoc analysis showed that smoking and ASA class increased the risk for atelectasis.Conclusion, the effect of reducing FIO2 during preoxygenation to prevent atelectasis might be short-lived. A lower FIO2 shortened the time to the appearance of hypoxia. Increasing lung volume by using CPAP/PEEP also decreased the risk of atelectasis, but the method might fail; for example in patients who are heavy smokers. In older patients care must be taken to reduce a high FIO2 before ending CPAP.
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| 3. |
- Gohardani, Navid, 1979-
(författare)
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An Approach Towards Sustainable Building
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The motivation for development of energy efficiency and implementation of novel advanced materials applied in buildings can be traced to increasing energy costs in conjunction with an enhanced environmental awareness among people. This doctoral dissertation presents contributions towards sustainable building, where factors such as building technology, energy efficiency in buildings, workers' health issues during construction measures, and certain economic considerations for renovation of buildings have been considered. The research study aims to provide a knowledge base for motivating building owners to renovate buildings based on energy efficiency and improved indoor environment. The initial phase of the research study identifies a detailed description of common drivers, expected in renovation projects by building owners. In the second phase, an information base is identified which may facilitate the bidding processes for decision makers by means of technological, social and economic aspects. The aforementioned information base can also contribute to attentive decisions regarding sustainable renovation and energy saving measures. A strategy was developed within the Renovation Workshop of Riksbyggen, in order to promote energy saving measures concurrent with major renovations in residential buildings. This operational decision support process was applied in a tenant owners' cooperative in Sweden. The objective of this process was to showcase and more importantly to implement energy saving measures, based on knowledge transfer between different parties involved in the renovation project. For the conducted case study, this process was shown to be of great importance when decisions regarding energy saving measures in conjunction with scheduled renovations are being planned. A unique case study was conducted on two of the most commonly used environmental certification programs for buildings in Sweden; Environmental Building (Miljöbyggnad) and GreenBuilding. Following a granted access to a limited database of submitted applications to Sweden Green Building Council, the most common mistakes in these were identified and categorized. This study contributed to further understanding about the level of ability among building consultants, comprehension of environmental certification, and enhancement of the ability to produce high-quality calculations concerning building-related energy usage. In addition, this insight can provide a basis for planning of continuing education of consultants within the field of building technology. For a church building, a study was conducted subsequent to an exchange of an existing electric coil heating system to a hydronic ground source heat pump system. Analyses of the energy demand and energy signature, prior to and after installation were carried out. The replacement of the original heating system with a ground source heat pump system for the church building constitutes a reduced energy consumption level of approximately 66%, at the average outside temperature of -2.30 °C. This study demonstrated that data from a detailed electric bill can be utilized in order to obtain the energy signature of the building and henceforth assess the energy savings. One aspect of the research, examined the decision making process related to sustainable renovation and refurbishment in buildings. The utilized methodology identified three distinct phases in order to instigate an engagement in sustainable renovation, by means of questionnaires and semi-structured interviews. In particular, the attitudes of stakeholders in Sweden, Denmark and Cyprus to sustainable building were studied through three separate case studies. Within the framework of this study, it was identified that building physics and durability are among the most important drivers for energy renovation. The results provided an insight into the renovation process in the aforementioned countries and identified that drivers such as improvement of indoor air quality and elimination of moisture in the building envelope are also of crucial importance. Another aspect of the conducted research highlights workplace accidents occurring within the Swedish construction sector. The purpose of this study was to serve as a useful tool to track the working environments of construction workers in order to reduce health and safety issues within the construction sector. The findings of this research suggest that despite laws, regulations or additional factors that seek to ensure a safe and healthy environment for construction workers, the Swedish construction work force still faces challenges. Moreover, it is identified that construction workers participating in the study call for additional measures to ensure occupational health and safety. Improved knowledge of economic performance and technical results of renovations can contribute to a snowball effect, with more property owners recognizing the value of energy aspects and thus provide an increased level of energy savings.
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| 4. |
- Schönbeck, Pia
(författare)
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Use of configuration information in construction projects to ensure high performance of healthcare facilities
- 2020
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The transfer of information between the different phases of construction projects is limited, which complicates the quality assurance of configurations. Functional requirements on the building configuration are often ambiguous and lack measurable acceptance criteria. Vaguely described criteria provide an insufficient basis for the design and verification acceptance values. The contractor is often the first to consider the feasibility just before or during the production phase. However, feasibility including production methods should be considered with the establishment of each design solutions. Costs or time consequences are often the basis for change decisions, while the investigations of the impact on the building configuration and functionality are insufficient. A continuous flow of information with functional requirements as a controlling factor is required to control configurations. Functionality that ensure high quality patient care are essential in health care facilities, therefore the control of the configurations are particularly important.This licentiate thesis shows how configuration information in healthcare construction projects can ensure necessary building functionality. The following information areas are identified as necessary for control of configurations: function, verification, design solution, production and change control. All information is related and changes in one area affect the others, directly or indirectly during construction projects. The studies that are the basis of this licentiate thesis show that the management of configuration information was deficient in healthcare construction projects, especially regarding availability and interconnectivity. In addition, the information was not available at the right time during the construction process, which impaired configuration control. For example, verification methods were not available until the end of production. This precluded verification of intended functionality through large parts of the construction project. Detailed change information from digital models of buildings can significantly improve control of configurations, but this requires standardisation of input data.In the manufacturing industry, configuration management is practised to ensure that products fulfil the required functions throughout their entire lifecycle. Development of new technologies, such as digital processes and industrialised construction, require that construction projects develop working processes similar to those of the manufacturing industry. The risk of unnecessary rework with subsequent cost increases, delays and environmental impact decrease with increased control of the configuration. In construction projects, systematic management of configuration information can ensure delivery of healthcare facilities with intended functionality.
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