Martin Hultman
Linköping University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Martin Hultman.
Small Enterprise Research | 2016
Tamara Galkina; Martin Hultman
This article assesses ecopreneurship from the point of view of an admittance-seeking social movement. We use the three criteria for evaluating the present status of the ecopreneurship research domain - differentiation, mobolization, and legitimacy building. Our analysis shows that ecopreneurship is still in the early stages of its development as a field of academic study, thus its further development in terms of theoretical contributions, questions to be asked, and research design must be understood in relation to its current status. We conclude that ecopreneurship research should remain open to the contributions from other fields of study in order to formulate its goals more precisely and to build a more solid foundation as an area of scientific inquiry.
Small enterprise research: the journal of SEAANZ | 2016
Martin Hultman; Karl Johan Bonnedahl; Kirstie O'Neill
Unsustainable societies – sustainable businesses? : Introduction to special issue of small enterpriseresearch on transitional Ecopreneurs
Journal of Biophotonics | 2018
Martin Hultman; Ingemar Fredriksson; Marcus Larsson; Atila Alvandpour; Tomas Strömberg
A multiple exposure laser speckle contrast imaging (MELSCI) setup for visualizing blood perfusion was developed using a field programmable gate array (FPGA), connected to a 1000 frames per second (fps) 1-megapixel camera sensor. Multiple exposure time images at 1, 2, 4, 8, 16, 32 and 64 milliseconds were calculated by cumulative summation of 64 consecutive snapshot images. The local contrast was calculated for all exposure times using regions of 4 × 4 pixels. Averaging of multiple contrast images from the 64-millisecond acquisition was done to improve the signal-to-noise ratio. The results show that with an effective implementation of the algorithm on an FPGA, contrast images at all exposure times can be calculated in only 28 milliseconds. The algorithm was applied to data recorded during a 5 minutes finger occlusion. Expected contrast changes were found during occlusion and the following hyperemia in the occluded finger, while unprovoked fingers showed constant contrast during the experiment. The developed setup is capable of massive data processing on an FPGA that enables processing of MELSCI data in 15.6 fps (1000/64 milliseconds). It also leads to improved frame rates, enhanced image quality and enables the calculation of improved microcirculatory perfusion estimates compared to single exposure time systems.
High-Speed Biomedical Imaging and Spectroscopy III: Toward Big Data Instrumentation and Management | 2018
Martin Hultman; Ingemar Fredriksson; Marcus Larsson; Tomas Strömberg
We present a first evaluation of a new multi-exposure laser speckle contrast imaging (MELSCI) system for assessing spatial variations in the microcirculatory perfusion. The MELSCI system is based on a 1000 frames per second 1-megapixel camera connected to a field programmable gate arrays (FPGA) capable of producing MELSCI data in realtime. The imaging system is evaluated against a single point laser Doppler flowmetry (LDF) system during occlusionrelease provocations of the arm in five subjects. Perfusion is calculated from MELSCI data using current state-of-the-art inverse models. The analysis displayed a good agreement between measured and modeled data, with an average error below 6%. This strongly indicates that the applied model is capable of accurately describing the MELSCI data and that the acquired data is of high quality. Comparing readings from the occlusion-release provocation showed that the MELSCI perfusion was significantly correlated (R=0.83) to the single point LDF perfusion, clearly outperforming perfusion estimations based on a single exposure time. We conclude that the MELSCI system provides blood flow images of enhanced quality, taking us one step closer to a system that accurately can monitor dynamic changes in skin perfusion over a large area in real-time.
Futures | 2009
Martin Hultman
Posthumanistiska nyckeltexter | 2012
Cecilia Åsberg; Martin Hultman; Francis Lee
Linköping studies in arts and science | 2010
Martin Hultman
INTER: A European Cultural Studies Conference In Sweden. ACSIS, Norrköping, Sweden, June 11-13 | 2007
Francis Lee; Martin Hultman
Technologies of nature-politics, Oslo, Norway, February 2-3 | 2006
Francis Lee; Martin Hultman
Kulturstudier i Sverige. Nationell forskarkonferens | 2005
Martin Hultman