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- Danielski, Itai, 1973-
(author)
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Energy performance of residential buildings : projecting, monitoring and evaluating
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Energy security and climate change mitigation have been discussed in Sweden since the oil crisis in the 1970s. Sweden has since then increased its share of renewable energy resources to reach the highest level among the EU member states, but is still among the countries with the highest primary energy use per capita. Not least because of that, increasing energy efficiency is important and it is part of the Swedish long term environmental objectives. Large potential for improving energy efficiency can be found in the building sector, mainly in the existing building stock but also in new constructions.Buildings hold high costs for construction, service and maintenance. Still, their energy efficiency and thermal performance are rarely validated after construction or renovation. As energy efficiency become an important aspects in building design there is a need for accurate tools for assessing the energy performance both before and after building construction. In this thesis criteria for energy efficiency in new residential buildings are studied. Several building design aspects are discussed with regards to final energy efficiency, energy supply-demand interactions and social aspects. The results of this thesis are based on energy modelling, energy measurements and one questionnaire survey. Several existing residential buildings were used as case studies.The results show that pre-occupancy calculations of specific final energy demand in residential buildings is too rough an indicator to explicitly steer towards lower final energy use in the building sector. Even post occupancy monitoring of specific final energy demand does not always provide a representative image of the energy efficiency of buildings and may result with large variation among buildings with similar thermal efficiency. A post occupancy method of assessing thermal efficiency of building fabrics using thermography is presented. The thermal efficiency of buildings can be increased by design with low shape factor. The shape factor was found to have a significant effect on the final energy demand of buildings and on the use of primary energy. In Nordic climates, atria in multi-storey apartment buildings is a design that have a potential to increase both energy efficiency (by lower shape factor) and enhance social interactions among the occupants.
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| 2. |
- Danielski, Itai, et al.
(author)
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The impact of the shape factor on final energy demand in residential buildings in nordic climates
- 2012
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In: World Renewable Energy Forum, WREF 2012, Including World Renewable Energy Congress XII and Colorado Renewable Energy Society (CRES) Annual Conference. - 9781622760923 ; , s. 4260-4264
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Conference paper (other academic/artistic)abstract
- The shape factor of a building is the ratio between its envelope area and its volume. Buildings with a higher shape factor have a larger surface area in proportion to their volume, which results in larger heat losses in cold climates. This study analyzes the impact of the shape factor on the final energy demand by using five existing apartment buildings with different values of shape factor. Each building was simulated for twelve different scenarios: three thermal envelope scenarios and four climate zones. The differences in shape factor between the buildings were found to have a large impact and accounted for 10%-20% of their final energy demand. The impact of the shape factor was reduced with warmer climates and ceased with average outdoor temperature 11ºC-14ºC depending on the thermal envelope performance of the buildings.
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| 3. |
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| 4. |
- Danielski, Itai, et al.
(author)
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Heated atrium in multi-storey apartment buildings, a design with potential to enhance energy efficiency and to facilitate social interactions
- 2016
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In: Building and Environment. - : Elsevier. - 0360-1323 .- 1873-684X. ; 106, s. 352-364
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Journal article (peer-reviewed)abstract
- The design concept of conditioned atria gains increasing popularity in commercial and service buildings all over the world, but is still not a common building design in the residential sector. This study investigates the potential of such design in residential buildings in Nordic climates as means to enhance both energy efficiency as well as social interaction among residents. Energy modelling was used to compare energy efficiency among designs of residential buildings with and without atrium and to identify important design parameters. Social interaction was analysed, based on a survey evaluating the perception of residents living in an existing multi-storey apartment building designed with a heated atrium in the north of Sweden.The results show that heated atrium in Nordic climates have a potential to reduce the total final energy demand while at the same time increase the conditioned space of the building. To positively impact energy efficiency, the atrium should fulfil three requirements: (i) it should be designed to reduce the shape factor for the whole building; (ii) it should have the minimum glazed area that comply with the building requirements concerning natural light and visual comfort; and (iii) adjustable solar shading should be installed in the atrium’s façades to avoid unwanted overheating. The survey results indicate that the additional space created by the atrium has a potential to facilitate and promote social interaction among residents and to increases a sense of neighbourliness and belongingness, which are often discussed as important parameters in relation to social sustainability.
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| 5. |
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| 6. |
- Nilsen, Morgan, et al.
(author)
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In-process Monitoring and Control of Robotized Laser Beam Welding of Closed Square Butt Joints
- 2018
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In: Procedia Manufacturing. - : Elsevier BV. - 2351-9789. ; 25, s. 511-516
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Journal article (peer-reviewed)abstract
- In robotized laser welding of technical zero gap closed square butt joints it is critical to position the laser beam correct with regardsto the joint. Welding with an offset from the joint may cause lack of sidewall fusion, a serious defect that is hard to detect and gives a weak weld . When using machined parts with gap and misalignment between the parts that is close to zero, existing joint tracking systems will probably fail to track the joint. A camera based system using LED illumination and matching optical filters is proposed in this paper to address this issue. A high dynamic range CMOS camera and the LED illumination is integrated into the laser tool. The camera captures images of the area in front of the melt pool where the joint is visible and an algorithm based on the Hough transform and a Kalman filter estimates the offset between the laser spot and the joint position. Welding experiments, using a 6 kW fiber laser, have been conducted to evaluate the performance of the system. Promising results are obtained that can be used in the further development of a closed loop controlled joint tracking system.
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| 7. |
- Sikström, Fredrik, et al.
(author)
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Evaluation of non-contact methods for joint tracking in a laser beam welding application
- 2016
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In: The 7th International Swedish Production Symposium, Conference Proceedings. - Lund : Swedish Production Symposium. ; , s. 1-6
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Conference paper (peer-reviewed)abstract
- The use of automated laser welding is a key enabler for resource efficient manufacturing in several industrial sectors. One disadvantage with laser welding is the narrow tolerance requirements in the joint fit-up. This is the main reason for the importance of joint tracking systems. This paper describes anevaluation of four non-contact measurement methods to measure the position, gap width and misalignment between superalloy plates. The evaluation was carried out for increased knowledge about the possibilities and limitations with the different methods. The methods are vision-, laser-line-,thermography- and inductive probe systems which are compared in an experimental setup representing a relevant industrial application. Vision is based on a CMOS camera, where the image information is used directly for the measurements. Laser-line is based on triangulation between a camera and a projected laserline. Thermography detects the heat increase in the gap width due to external heat excitation. Inductive probe uses two eddy current coils, and by a complex response method possibilities to narrow gap measurement is achieved. The results, evaluated by comparing the data from the different systems, clearly highlights possibilities and limitations with respective method and serves as a guide in the development of laser beam welding.
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| 8. |
- Hönel, Sebastian, et al.
(author)
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Contextual Operationalization of Metrics as Scores : Is My Metric Value Good?
- 2022
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In: Proceedings of the 2022 IEEE 22nd International Conference on Software Quality, Reliability and Security (QRS). - : IEEE. - 9781665477048 ; , s. 333-343
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Conference paper (peer-reviewed)abstract
- Software quality models aggregate metrics to indicate quality. Most metrics reflect counts derived from events or attributes that cannot directly be associated with quality. Worse, what constitutes a desirable value for a metric may vary across contexts. We demonstrate an approach to transforming arbitrary metrics into absolute quality scores by leveraging metrics captured from similar contexts. In contrast to metrics, scores represent freestanding quality properties that are also comparable. We provide a web-based tool for obtaining contextualized scores for metrics as obtained from one’s software. Our results indicate that significant differences among various metrics and contexts exist. The suggested approach works with arbitrary contexts. Given sufficient contextual information, it allows for answering the question of whether a metric value is good/bad or common/extreme.
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| 9. |
- Kumar, Abhinav, et al.
(author)
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Enrichment of immunoregulatory proteins in the biomolecular corona of nanoparticles within human respiratory tract lining fluid
- 2016
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In: Nanomedicine. - : Elsevier BV. - 1549-9634 .- 1549-9642. ; 12:4, s. 1033-1043
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Journal article (peer-reviewed)abstract
- When inhaled nanoparticles deposit in the lungs, they transit through respiratory tract lining fluid (RTLF) acquiring a biomolecular corona reflecting the interaction of the RTLF with the nanomaterial surface. Label-free snapshot proteomics was used to generate semiquantitative profiles of corona proteins formed around silica (SiO2) and poly(vinyl) acetate (PVAc) nanoparticles in RTLF, the latter employed as an archetype drug delivery vehicle. The evolved PVAc corona was significantly enriched compared to that observed on SiO2 nanoparticles (698 vs. 429 proteins identified); however both coronas contained a substantial contribution from innate immunity proteins, including surfactant protein A, napsin A and complement (C1q and C3) proteins. Functional protein classification supports the hypothesis that corona formation in RTLF constitutes opsonisation, preparing particles for phagocytosis and clearance from the lungs. These data highlight how an understanding of the evolved corona is necessary for the design of inhaled nanomedicines with acceptable safety and tailored clearance profiles. From the Clinical Editor: Inhaled nanoparticles often acquire a layer of protein corona while they go through the respiratory tract. Here, the authors investigated the identity of these proteins. The proper identification would improve the understanding of the use of inhaled nanoparticles in future therapeutics. (C) 2016 Published by Elsevier Inc.
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| 10. |
- Picha, Petr, et al.
(author)
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Process anti-pattern detection : a case study
- 2022
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In: Proceedings of the 27th European Conference on Pattern Languages of Programs, EuroPLop 2022, Irsee, Germany, July 6-10, 2022. - New York, NY, USA : ACM Publications. - 9781450395946 ; , s. 1-18
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Conference paper (peer-reviewed)abstract
- Anti-patterns are harmful phenomena repeatedly occurring, e.g., in software development projects. Though widely recognized and well-known, their descriptions are traditionally not fit for automated detection. The detection is usually performed by manual audits, or on business process models. Both options are time-, effort- and expertise-heavy, prone to biases, and/or omissions. Meanwhile, collaborative software projects produce much data as a natural side product, capturing their status and day-to-day history. Long-term, our research aims at deriving models for the automated detection of process and project management anti-patterns, applicable to project data. Here, we present a general approach for studies investigating occurrences of these types of anti-patterns in projects and discuss the entire process of such studies in detail, starting from the anti-pattern descriptions in literature. We demonstrate and verify our approach with the Fire Drill anti-pattern detection as a case study, applying it to data from 15 student projects. The results of our study suggest that reliable detection of at least some process and project management anti-patterns in project data is possible, with 13 projects assessed accurately for Fire Drill presence by our automated detection when compared to the ground truth gathered from independent data. The overall approach can be similarly applied to detecting patterns and other phenomena with manifestations in Application Lifecycle Management data.
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