| 1. |
- Abou-Taouk, Abdallah, 1982, et al.
(författare)
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CFD INVESTIGATION OF SWIRL-STABILIZED FLEXI-FUEL BURNER USING METHANE-AIR MIXTURE FOR GAS TURBINES
- 2011
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Ingår i: International Society for Airbreathing Engines, ISABE, Gothenburg, 2011. ; 1, s. 160-172
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Konferensbidrag (refereegranskat)abstract
- Combustion modeling based on a multi-step global reaction mechanism [1] is applied to CFD (Computational Fluid Dynamics) analysis of a scaled swirl-stabilized 4th generation premixed DLE (Dry Low Emission) burner for gas turbines. The flexi-fuel burner consists of a MAIN pre-mixed flame, a premixed PILOT flame and a confined RPL (Rich Pilot Lean) flame. Both steady-state RANS (Reynolds Averaged Navier Stokes) and hybrid URANS/LES (Unsteady RANS/Large Eddy Simulation) results have been computed. The results are compared with high quality experimental data in the form of emission data, PIV (Particle Image Velocimetry) data and OH-PLIF (Planar Laser Induced Fluorescence Imaging) from an atmospheric burner test rig at Lund University [2-3]. There is a good agreement between the CFD simulations and measurements of emissions, velocity field and flame visualization.
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| 2. |
- Almström, Peter, 1972, et al.
(författare)
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Achieving Sustainable Production through Increased Utilization of Production Resources
- 2011
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Ingår i: Proceedings of the 4th Swedish Production Symposium, SPS11, Lund, May 3-5, 2011. ; , s. 398-406
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Konferensbidrag (refereegranskat)abstract
- There seems to be a quite divergent view on sustainable production, mainly based on the perspective applied. From a global perspective, every kind of material consumption and growth is basically unwanted and should be minimized. This reflects in economic sustainability parameters that point towards producing as little as possible and socialparameters pointing at eliminating abuse of human rights etc. On the other hand, international summits on sustainability have stated that it is a human right to have a certain standard of living, which implies increase in production but with less resource consumption. This global perspective is however not very helpful when focusing on more local level, for example Swedish manufacturing industry. To achieve a long-term jobsecurity the manufacturing companies need to be long-term prosperous. Further, to be able to maintain profitability levels, manufacturing companies need to continuouslyincrease productivity. Utilization deals with using production equipment in a cost efficient way and this article will highlight how utilization affects different aspects of sustainable production, the link between utilization and productivity, as well as practical considerations when improving utilization in manufacturing industry.
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| 3. |
- Avdovic, Pajazit, 1955, et al.
(författare)
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Evaluating the machinability of Inconel 718 using polar diagrams
- 2010
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Ingår i: Proceedings of the ASME Turbo Expo 2010: Power for Land, Sea, and Air, GT 2010, Glasgow, United Kingdom, 14-18 June 2010. - 9780791843963 ; , s. 987-996
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Konferensbidrag (refereegranskat)abstract
- The use of a polar diagram method for describing and evaluating the machinability of Inconel 718 was explored. Five key parameters of the work material, representing the mechanical and physical properties which have strongest influence on its machinability, were employed in the diagrams. These five parameters were integrated into a single polar diagram, used to describe the machinability of Inconel 718. Variations in the machinability of Inconel 718 products or components of a given type produced in different batches were analyzed. Industrial experiments were conducted to test the relationship between the polar diagram of the work material, its carbon content, and tool wear of the ceramic cutting tools used in machining it. Work materials of Inconel 718 in which the polar diagrams of machinability were similar in size and shape exhibited very similar behavior during the cutting process. The polar diagram method employed appeared to be useful for selecting suitable cutting data for the machining of new materials.
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| 4. |
- Beech, J. P., et al.
(författare)
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What do photons do to fluorescently stained DNA in confinement?
- 2013
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Ingår i: 17th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2013; Freiburg; Germany; 27 October 2013 through 31 October 2013. ; 1, s. 5-7
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Konferensbidrag (refereegranskat)abstract
- We have studied a selection of factors influencing the damage of DNA in nanochannels during fluorescence imaging. For cutting and nicking of DNA we show that the DNA is shortened during imaging. To avoid photodamage over the course of several hours of a typical experiment, we demonstrate the importance of an oxygen free gas to propel the buffer solution through the device. Finally, by varying the size of the channels, we show indications that higher DNA concentrations lead to higher rates of photodamage necessitating a balance between needs for highly stretched DNA and needs for long measurement times.
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| 5. |
- Berntsson Svensson, Richard, et al.
(författare)
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Prioritization of quality requirements : State of practice in eleven companies
- 2011
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Ingår i: 2011 IEEE 19th International Requirements Engineering Conference, RE 2011; Trento; 29 August 2011 through 2 September 2011. - Trento : IEEE. - 9781457709234 ; , s. 69-78, s. 69-78
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Konferensbidrag (refereegranskat)abstract
- Requirements prioritization is recognized as an important but challenging activity in software product development. For a product to be successful, it is crucial to find the right balance among competing quality requirements. Although literature offers many methods for requirements prioritization, the research on prioritization of quality requirements is limited. This study identifies how quality requirements are prioritized in practice at 11 successful companies developing software intensive systems. We found that ad-hoc prioritization and priority grouping of requirements are the dominant methods for prioritizing quality requirements. The results also show that it is common to use customer input as criteria for prioritization but absence of any criteria was also common. The results suggests that quality requirements by default have a lower priority than functional requirements, and that they only get attention in the prioritizing process if decision-makers are dedicated to invest specific time and resources on QR prioritization. The results of this study may help future research on quality requirements to focus investigations on industry-relevant issues.
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| 6. |
- Borin, Lars, 1957, et al.
(författare)
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Mining semantics for culturomics: towards a knowledge-based approach
- 2013
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Ingår i: 2013 ACM International Workshop on Mining Unstructured Big Data Using Natural Language Processing, UnstructureNLP 2013, Held at 22nd ACM International Conference on Information and Knowledge Management, CIKM 2013; San Francisco, CA; United States; 28 October 2013 through 28 October 2013. - New York, NY, USA : ACM. - 9781450324151 ; , s. 3-10
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Konferensbidrag (refereegranskat)abstract
- The massive amounts of text data made available through the Google Books digitization project have inspired a new field of big-data textual research. Named culturomics, this field has attracted the attention of a growing number of scholars over recent years. However, initial studies based on these data have been criticized for not referring to relevant work in linguistics and language technology. This paper provides some ideas, thoughts and first steps towards a new culturomics initiative, based this time on Swedish data, which pursues a more knowledge-based approach than previous work in this emerging field. The amount of new Swedish text produced daily and older texts being digitized in cultural heritage projects grows at an accelerating rate. These volumes of text being available in digital form have grown far beyond the capacity of human readers, leaving automated semantic processing of the texts as the only realistic option for accessing and using the information contained in them. The aim of our recently initiated research program is to advance the state of the art in language technology resources and methods for semantic processing of Big Swedish text and focus on the theoretical and methodological advancement of the state of the art in extracting and correlating information from large volumes of Swedish text using a combination of knowledge-based and statistical methods.
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| 7. |
- Claesson, Johan, 1943, et al.
(författare)
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A load-aggregation method to calculate extraction temperatures of borehole heat exchangers
- 2012
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Ingår i: ASHRAE Transactions. - 0001-2505. ; 118:1, s. 530-539
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Konferensbidrag (refereegranskat)abstract
- Hourly simulations of extraction fluid temperatures from borehole heat exchangers tend to be very time consuming. A new load aggregation scheme to perform long-term simulations of borehole heat exchangers is presented. The starting point is the step-response function for the considered borehole heat exchanger and the corresponding long sequence of cells, each with a load and a weighting factor. On the first level, the original weighting factors are kept. On the following levels, 2, 4, 8, etc., the weighting factors are lumped together. The lumped weighting factors are obtained directly from the step-response function. The number of cells to be lumped together is chosen so that the extraction temperatures using lumped weighting factors give a sufficiently good approximation of the non-aggregated scheme. The new scheme is applied to a test case to simulate extraction fluid temperature over a 20-year time period. Comparison of the results from the new scheme with the non-aggregated setting shows that the new scheme can perform very accurate and fast simulations of borehole heat exchangers.
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| 8. |
- Coldrey, Mikael, 1972, et al.
(författare)
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Higher order MIMO outdoor-to-indoor measurements using repeaters
- 2010
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Ingår i: IEEE Vehicular Technology Conference. - 1550-2252. - 9781424425198
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In this paper we present results from a outdoor- to-indoor MIMO measurement campaign where we study the effect of repeaters on singular values, spatial richness, capacity, and delay spread distributions. We present results from different repeater scenarios such as, e.g. different outdoor/indoor repeater deployments with single/dual polarized antennas. The measurements show that repeaters significantly enhance the received SNR while they increase the delay spread and decrease the spatial richness of the MIMO channel. However, the main conclusion is that a significant increase in channel capacity is attained when deploying repeaters mostly thanks to their ability to provide spatial multiplexing over the high-quality eigenmodes they may provide. The number of such eigenmodes is limited by the number of repeaters, deployment, and their antennas. © 2010 IEEE.
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| 9. |
- Emilsson, Gustav, 1989, et al.
(författare)
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Identifying bacteria using DNA binding maps
- 2013
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Ingår i: 17th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2013; Freiburg; Germany; 27 October 2013 through 31 October 2013. - 9781632666246 ; 1, s. 473-475
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Konferensbidrag (refereegranskat)abstract
- We have developed an assay, based on nanofluidic channels and fluorescence microscopy, for optical mapping of DNA based on competitive binding between two molecules - one fluorescent and one sequence selective. From the experimental data we can extract binding constants for the two competing DNA binders, which may be subsequently used to calculate a theoretical reference map of any DNA with known sequence. The goal is to create a method for fast identification of bacteria from single DNA molecules without the need for additional cultivation or amplification. We here demonstrate a proof-of-principle experiment on phage DNA and furthermore show that the method can be used to distinguish between two strains of E. coli DNA and to map pieces of DNA onto the full genome.
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| 10. |
- Engström, Emelie, et al.
(författare)
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Indirect effects in evidential assessment: A case study on regression test technology adoption
- 2012
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Ingår i: 2nd International Workshop on Evidential Assessment of Software Technologies, EAST 2012. Lund, 22 September 2012. - New York, NY, USA : ACM. - 9781450315098 ; , s. 15-20
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Konferensbidrag (refereegranskat)abstract
- Background: There is a need for effcient regression testing in most software development organizations. Often the proposed solutions involve automation. However, despite this being a well researched area, research results are rarely applied in industrial practice. Aim: In this paper we aim to bridge the gap between research and practice by providing examples of how evidence-based regression testing approaches can be adopted in industry. We also discuss challenges for the research community. Method: An industrial case study was carried out to evaluate the possibility to improve regression testing at Sony Ericsson Mobile Communications. We analyse the procedure undertaken based on frameworks from the evidence based software engineering, EBSE, paradigm (with a focus on the evidence) and automation literature (with a focus on the practical effects). Results: Our results pinpoint the need for systematic approaches when introducing a new tool. Practitioners and researchers need congruent guidelines supporting the appraisal of both the evidence base and the pragmatic effects, both direct but also indirect, of the changes. This is illustrated by the introduction of the automation perspective.
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