| 1. |
|
|
| 2. |
- Balliu, Musard, et al.
(författare)
-
Challenges of Producing Software Bill of Materials for Java
- 2023
-
Ingår i: IEEE Security and Privacy. - : Institute of Electrical and Electronics Engineers (IEEE). - 1540-7993 .- 1558-4046. ; 21:6, s. 12-23
-
Tidskriftsartikel (refereegranskat)abstract
- Software bills of materials (SBOMs) promise to become the backbone of software supply chain hardening. We deep-dive into six tools and the SBOMs they produce for complex open source Java projects, revealing challenges regarding the accurate production and usage of SBOMs.
|
|
| 3. |
- Balliu, Musard, et al.
(författare)
-
Software Bill of Materials in Java
- 2023
-
Ingår i: SCORED 2023 - Proceedings of the 2023 Workshop on Software Supply Chain Offensive Research and Ecosystem Defenses. - : Association for Computing Machinery (ACM). ; , s. 75-76
-
Konferensbidrag (refereegranskat)abstract
- Modern software applications are virtually never built entirely in-house. As a matter of fact, they reuse many third-party dependencies, which form the core of their software supply chain [1]. The large number of dependencies in an application has turned into a major challenge for both security and reliability. For example, to compromise a high-value application, malicious actors can choose to attack a less well-guarded dependency of the project [2]. Even when there is no malicious intent, bugs can propagate through the software supply chain and cause breakages in applications. Gathering accurate, upto- date information about all dependencies included in an application is, therefore, of vital importance.
|
|
| 4. |
- Lachonius, Maria, 1962, et al.
(författare)
-
Socioeconomic factors and long-term mortality risk after surgical aortic valve replacement.
- 2023
-
Ingår i: International journal of cardiology. Cardiovascular risk and prevention. - 2772-4875. ; 19
-
Tidskriftsartikel (refereegranskat)abstract
- There is scarce knowledge about the association between socioeconomic status and mortality in patients undergoing surgical aortic valve replacement. This study explores the associations between income, education and marital status, and long-term mortality risk.In this national registry-based observational cohort study we included all 14,537 patients aged >18 years who underwent isolated surgical aortic valve replacement for aortic stenosis in Sweden 1997-2020. Socioeconomic status and comorbidities were collected from three mandatory national registries. Cox regression models adjusted for patient characteristics and comorbidities were used to estimate the mortality risk.Mortality risk was higher for patients in the lowest versus the highest income quintile (adjusted hazard ratio [aHR] 1.36, 95% confidence interval [CI]: 1.11-1.65), for patients with <10 years education versus >12 years (aHR 1.20, 95% CI:1.08-1.33), and for patients who were not married/cohabiting versus those who were (aHR 1.24, 95% CI:1.04-1.48). Patients with the most unfavorable socioeconomic status (lowest income, shortest education, never married/cohabiting) had an adjusted median survival of 2.9 years less than patients with the most favorable socioeconomic status (14.6 years, 95% CI: 13.2-17.4 years vs. 11.7 years, 95% CI: 9.8-14.4).Low socioeconomic status in patients undergoing surgical aortic valve replacement is associated with shorter survival and an increased long-term adjusted mortality risk. These results emphasize the importance of identifying surgical aortic valve replacement patients with unfavorable socioeconomic situation and ensure sufficient post-discharge surveillance.
|
|
| 5. |
- Skoglund, Martin, et al.
(författare)
-
Comparing In-ear EOG for Eye-Movement Estimation With Eye-Tracking : Accuracy, Calibration, and Speech Comprehension
- 2022
-
Ingår i: Frontiers in Neuroscience. - : Frontiers Media SA. - 1662-4548 .- 1662-453X. ; 16
-
Tidskriftsartikel (refereegranskat)abstract
- This presentation details and evaluates a method for estimating the attended speaker during a two-person conversation by means of in-ear electro-oculography (EOG). Twenty-five hearing-impaired participants were fitted with molds equipped with EOG electrodes (in-ear EOG) and wore eye-tracking glasses while watching a video of two life-size people in a dialog solving a Diapix task. The dialogue was directionally presented and together with background noise in the frontal hemisphere at 60 dB SPL. During three conditions of steering (none, in-ear EOG, conventional eye-tracking), participants comprehension was periodically measured using multiple-choice questions. Based on eye movement detection by in-ear EOG or conventional eye-tracking, the estimated attended speaker was amplified by 6 dB. In the in-ear EOG condition, the estimate was based on one selected channel pair of electrodes out of 36 possible electrodes. A novel calibration procedure introducing three different metrics was used to select the measurement channel. The in-ear EOG attended speaker estimates were compared to those of the eye-tracker. Across participants, the mean accuracy of in-ear EOG estimation of the attended speaker was 68%, ranging from 50 to 89%. Based on offline simulation, it was established that higher scoring metrics obtained for a channel with the calibration procedure were significantly associated with better data quality. Results showed a statistically significant improvement in comprehension of about 10% in both steering conditions relative to the no-steering condition. Comprehension in the two steering conditions was not significantly different. Further, better comprehension obtained under the in-ear EOG condition was significantly correlated with more accurate estimation of the attended speaker. In conclusion, this study shows promising results in the use of in-ear EOG for visual attention estimation with potential for applicability in hearing assistive devices.
|
|
| 6. |
- Skoglund, Pontus, et al.
(författare)
-
Investigating population history using temporal genetic differentiation
- 2014
-
Ingår i: Molecular biology and evolution. - : Oxford University Press (OUP). - 0737-4038 .- 1537-1719. ; 31:9, s. 2516-2527
-
Tidskriftsartikel (refereegranskat)abstract
- The rapid advance of sequencing technology coupled with improvements in molecular methods for obtaining genetic data from ancient sources holds the promise of producing a wealth of genomic data from time-separated individuals. However, the population genetic properties of time-structured samples have not been extensively explored. Here, we consider the implications of temporal sampling for analyses of genetic differentiation, and use a temporal coalescent framework to show that complex historical events such as size reductions, population replacements, and transient genetic barriers between populations leave a footprint of genetic differentiation that can be traced through history using temporal samples. Our results emphasize explicit consideration of the temporal structure when making inferences, and indicate that genomic data from ancient individuals will greatly increase our ability to reconstruct population history.
|
|
| 7. |
- Warg, Fredrik, et al.
(författare)
-
The Quantitative Risk Norm - A Proposed Tailoring of HARA for ADS
- 2020
-
Ingår i: Proceedings of 2020 50th Annual IEEE/IFIP International Conference on Dependable Systems and Networks Workshops (DSN-W). - Los Alamitos. - 9781728172637
-
Konferensbidrag (refereegranskat)abstract
- One of the major challenges of automated drivingsystems (ADS) is showing that they drive safely. Key to ensuringsafety is eliciting a complete set of top-level safety requirements(safety goals). This is typically done with an activity called hazardanalysis and risk assessment (HARA). In this paper we argue thatthe HARA of ISO 26262:2018 is not directly suitable for an ADS,both because the number of relevant operational situations maybe vast, and because the ability of the ADS to make decisionsin order to reduce risks will affect the analysis of exposure andhazards. Instead we propose a tailoring using a quantitative risknorm (QRN) with consequence classes, where each class has alimit for the frequency within which the consequences may occur.Incident types are then defined and assigned to the consequenceclasses; the requirements prescribing the limits of these incidenttypes are used as safety goals to fulfil in the implementation.The main benefits of the QRN approach are the ability to showcompleteness of safety goals, and make sure that the safetystrategy is not limited by safety goals which are not formulatedin a way suitable for an ADS.
|
|
| 8. |
- Wilroth, Johanna, 1994-
(författare)
-
Exploring Auditory Attention Using EEG
- 2024
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Listeners with normal-hearing often overlook their ability to comprehend speech in noisy environments effortlessly. Our brain’s adeptness at identifying and amplifying attended voices while suppressing unwanted background noise, known as the cocktail party problem, has been extensively researched for decades. Yet, many aspects of this complex puzzle remain unsolved and listeners with hearing-impairment still struggle to focus on a specific speaker in noisy environments. While recent intelligent hearing aids have improved noise suppression, the problem of deciding which speaker to enhance remains unsolved, leading to discomfort for many hearing aid users in noisy environments.In this thesis, we explore the complexities of the human brain in challenging auditory environments. Two datasets are investigated where participants were tasked to selectively attend to one of two competing voices, replicating a cocktail-party scenario. The auditory stimuli trigger neurons to generate electrical signals that propagate in all directions. When a substantial number of neurons fire simultaneously, their collective electrical signal becomes detectable by small electrodes placed on the head. This method of measuring brain activity, known as electroencephalography (EEG), holds potential to provide feedback to the hearing aids, enabling adjustments to enhance attended voice(s).EEG data is often noisy, incorporating neural responses with artifacts such as muscle movements, eye blinks and heartbeats. In the first contribution of this thesis, we focus on comparing different manual and automatic artifact-rejection techniques and assessing their impact on auditory attention decoding (AAD).While EEG measurements offer high temporal accuracy, spatial resolution is inferior compared to alternative tools like magnetoencephalography (MEG). This difference poses a considerable challenge for source localization with EEG data. In the second contribution of this thesis, we demonstrate anticipated activity in the auditory cortex using EEG data from a single listener, employing Neuro-Current Response Functions (NCRFs). This method, previously evaluated only with MEG data, holds significant promise in hearing aid development.EEG data may involve both linear and nonlinear components due to the propagation of the electrical signals through brain tissue, skull, and scalp with varying conductivities. In the third contribution, we aim to enhance source localization by introducing a binning-based nonlinear detection and compensation method. The results suggest that compensating for some nonlinear components produces more precise and synchronized source localization compared to original EEG data.In the fourth contribution, we present a novel domain adaptation framework that improves AAD performances for listeners with initially low classification accuracy. This framework focuses on classifying the direction (left or right) of attended speech and shows a significant accuracy improvement when transporting poor data from one listener to the domain of good data from different listeners.Taken together, the contributions of this thesis hold promise for improving the lives of hearing-impaired individuals by closing the loop between the brain and hearing aids.
|
|
| 9. |
|
|
| 10. |
- Albert, Malin, et al.
(författare)
-
Hospitalized patients’ attitudes towards participating in a randomized control trial in case of a cardiac arrest
- 2024
-
Ingår i: Resuscitation Plus. - 2666-5204. ; 18
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundNo previous study has evaluated patients attitudes towards inclusion in an ongoing cardiac arrest clinical trial. The aim of this study was to assess patientś willingness and motives to participate in the ongoing randomized controlled drug trial “Vasopressin and Steroids in addition to Adrenaline in cardiac arrest” (VAST-A trial) in case of an in-hospital cardiac arrest (IHCA).ObjectivesHospitalized patients, men ≥ 18 and women ≥ 50 years, were asked for informed consent for inclusion in the VAST-A trial in case of an IHCA, the reason for approving or declining inclusion in the trial and baseline characteristics.MethodsPatients admitted to hospital were asked to give informed consent of inclusion in VAST-A in case of an IHCA during their hospital stay. Patients were also asked why they approved or declined inclusion as well as baseline characteristics questions.Results1,064 patients were asked about willingness to participate in the VAST-A trial, of these 902 (84.8%) patients approved inclusion. A subgroup of 411 patients were, except willingness, also asked about motives to participate or not and basic characteristics. The main reason for approving inclusion was to contribute to research (n = 328, 83.9%). The main reason for declining inclusion was concerns regarding testing the drug treatment (n = 6, 30%).ConclusionAmong hospitalized patients the vast majority gave informed consent to inclusion in an ongoing randomized cardiac arrest drug trial. The main reason for approving inclusion was to contribute to research.
|
|
| 11. |
- Alickovic, Emina, et al.
(författare)
-
Decoding Auditory Attention From EEG Data Using Cepstral Analysis
- 2023
-
Ingår i: ICASSPW 2023 - 2023 IEEE International Conference on Acoustics, Speech and Signal Processing Workshops, Proceedings. - : IEEE. - 9798350302615 - 9798350302622
-
Konferensbidrag (refereegranskat)abstract
- Recent studies of selective auditory attention have demonstrated that neural responses recorded with electroencephalogram (EEG) can be decoded to classify the attended talker in everyday multitalker cocktail-party environments. This is generally referred to as the auditory attention decoding (AAD) and could lead to a breakthrough for the next-generation of hearing aids (HAs) to have the ability to be cognitively controlled. The aim of this paper is to investigate whether cepstral analysis can be used as a more robust mapping between speech and EEG. Our preliminary analysis revealed an average AAD accuracy of 96%. Moreover, we observed a significant increase in auditory attention classification accuracies with our approach over the use of traditional AAD methods (7% absolute increase). Overall, our exploratory study could open a new avenue for developing new AAD methods to further advance hearing technology. We recognize that additional research is needed to elucidate the full potential of cepstral analysis for AAD.
|
|
| 12. |
- Alickovic, Emina, et al.
(författare)
-
Predicting EEG Responses to Attended Speech via Deep Neural Networks for Speech
- 2023
-
Ingår i: 2023 45TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE & BIOLOGY SOCIETY, EMBC. - : IEEE. - 9798350324471 - 9798350324488
-
Konferensbidrag (refereegranskat)abstract
- Attending to the speech stream of interest in multi-talker environments can be a challenging task, particularly for listeners with hearing impairment. Research suggests that neural responses assessed with electroencephalography (EEG) are modulated by listener's auditory attention, revealing selective neural tracking (NT) of the attended speech. NT methods mostly rely on hand-engineered acoustic and linguistic speech features to predict the neural response. Only recently, deep neural network (DNN) models without specific linguistic information have been used to extract speech features for NT, demonstrating that speech features in hierarchical DNN layers can predict neural responses throughout the auditory pathway. In this study, we go one step further to investigate the suitability of similar DNN models for speech to predict neural responses to competing speech observed in EEG. We recorded EEG data using a 64-channel acquisition system from 17 listeners with normal hearing instructed to attend to one of two competing talkers. Our data revealed that EEG responses are significantly better predicted by DNN-extracted speech features than by hand-engineered acoustic features. Furthermore, analysis of hierarchical DNN layers showed that early layers yielded the highest predictions. Moreover, we found a significant increase in auditory attention classification accuracies with the use of DNN-extracted speech features over the use of hand-engineered acoustic features. These findings open a new avenue for development of new NT measures to evaluate and further advance hearing technology.
|
|
| 13. |
- Axholt, Magnus, et al.
(författare)
-
Accuracy of Eyepoint Estimation in Optical See-Through Head-Mounted Displays Using the Single Point Active Alignment Method
- 2011
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper studies the accuracy of the estimated eyepoint of an Optical See-Through Head-Mounted Display (OST HMD) calibrated using the Single Point Active Alignment Method (SPAAM). Quantitative evaluation of calibration procedures for OST HMDs is complicated as it is currently not possible to share the subject’s view. Temporarily replacing the subject’s eye with a camera during the calibration or evaluation stage has been proposed, but the uncertainty of a correct eyepoint estimation remains. In the experiment reported in this paper, subjects were used for all stages of calibration and the results were verified with a 3D measurement device. The nine participants constructed 25 visual alignments per calibration after which the estimated pinhole camera model was decomposed into its intrinsic and extrinsic parameters using two common methods. Unique to this experiment, compared to previous evaluations, is the measurement device used to cup the subject’s eyeball. It measures the eyepoint location relative to the head tracker, thereby establishing the calibration accuracy of the estimated eyepoint location. As the results on accuracy are expressed as individual pinhole camera parameters, rather than a compounded registration error, this paper complements previously published work on parameter variance as the former denotes bias and the latter represents noise. Results indicate that the calibrated eyepoint is on average 5 cm away from its measured location and exhibits a vertical bias which potentially causes dipvergence for stereoscopic vision for objects located further away than 5.6 m. Lastly, this paper closes with a discussion on the suitability of the traditional pinhole camera model for OST HMD calibration.
|
|
| 14. |
- Axholt, Magnus, et al.
(författare)
-
Optical See-Through Head Mounted Display : Direct Linear Transformation Calibration Robustness in the Presence of User Alignment Noise
- 2010
-
Ingår i: Proceedings of the 54th Annual Meeting of the Human Factors and Ergonomics Society. - Linköping : Linköping University Electronic Press. - 9780945289371
-
Konferensbidrag (refereegranskat)abstract
- The correct spatial registration between virtual and real objects in optical see-through augmented reality implies accurate estimates of the user’s eyepoint relative to the location and orientation of the display surface. A common approach is to estimate the display parameters through a calibration procedure involving a subjective alignment exercise. Human postural sway and targeting precision contribute to imprecise alignments, which in turn adversely affect the display parameter estimation resulting in registration errors between virtual and real objects. The technique commonly used has its origin incomputer vision, and calibrates stationary cameras using hundreds of correspondence points collected instantaneously in one video frame where precision is limited only by pixel quantization and image blur. Subsequently the input noise level is several order of magnitudes greater when a human operator manually collects correspondence points one by one. This paper investigates the effect of human alignment noise on view parameter estimation in an optical see-through head mounted display to determine how well astandard camera calibration method performs at greater noise levels than documented in computer vision literature. Through Monte-Carlo simulations we show that it is particularly difficult to estimate the user’s eyepoint in depth, but that a greater distribution of correspondence points in depth help mitigate the effects of human alignment noise.
|
|
| 15. |
- Axholt, Magnus, et al.
(författare)
-
Parameter Estimation Variance of the Single Point Active Alignment Method in Optical See-Through Head Mounted Display Calibration
- 2011
-
Ingår i: Proceedings of the IEEE Virtual Reality Conference. - Piscataway, NJ, USA : IEEE. - 9781457700378 - 9781457700392 ; , s. 27-24
-
Konferensbidrag (refereegranskat)abstract
- The parameter estimation variance of the Single Point Active Alignment Method (SPAAM) is studied through an experiment where 11 subjects are instructed to create alignments using an Optical See-Through Head Mounted Display (OSTHMD) such that three separate correspondence point distributions are acquired. Modeling the OSTHMD and the subject's dominant eye as a pinhole camera, findings show that a correspondence point distribution well distributed along the user's line of sight yields less variant parameter estimates. The estimated eye point location is studied in particular detail. Thefindings of the experiment are complemented with simulated datawhich show that image plane orientation is sensitive to the numberof correspondence points. The simulated data also illustrates someinteresting properties on the numerical stability of the calibrationproblem as a function of alignment noise, number of correspondencepoints, and correspondence point distribution.
|
|
| 16. |
- Baranowska, Julia, et al.
(författare)
-
Associations between medical therapy after surgical aortic valve replacement for aortic stenosis and long-term mortality: a report from the SWEDEHEART registry.
- 2022
-
Ingår i: European heart journal. Cardiovascular pharmacotherapy. - : Oxford University Press (OUP). - 2055-6837 .- 2055-6845. ; 8:8, s. 837-846
-
Tidskriftsartikel (refereegranskat)abstract
- The association between use of statins, renin-angiotensin system (RAS) inhibitors and/or β-blockers and long-term mortality in patients with aortic stenosis who underwent surgical aortic valve replacement (SAVR) is unknown.All patients with aortic stenosis who underwent isolated first time SAVR in Sweden from 2006 to 2017 and survived six months after discharge were included. Individual patient data from four mandatory nationwide registries were merged. Cox proportional hazards models, with time-updated data on medication status and adjusted for age, sex, comorbidities, type of prosthesis, and year of surgery, were used to investigate associations between dispensed statins, RAS inhibitors, and β-blockers, and all-cause mortality. In total, 9553 patients were included, and median follow-up time was 4.9 years (range 0-11); 1738 patients (18.2%) died during follow-up. Statins were dispensed to 49.1% and 49.0% of the patients within six months of discharge from hospital and after ten years, respectively. Corresponding figures were 51.4% and 53.9% for RAS inhibitors, and 79.3% and 60.7% for β-blockers. Ongoing treatment was associated with lower mortality risk for statins [adjusted hazard ratio (aHR) 0.67 (95% confidence interval 0.60-0.74), p<0.001] and RAS inhibitors [aHR 0.84 (0.76-0.93), p<0.001] but not for β-blockers [aHR 1.17 (1.05-1.30), p=0.004]. The associations were robust in subgroups based on age, sex, and comorbidities (p for interactions>0.05).The results of this large population-based real-world study support the use of statins and RAS inhibitors for patients who underwent SAVR due to aortic stenosis.
|
|
| 17. |
- Bengtsson, Kenneth, et al.
(författare)
-
Så kan Sverige bli ledande nation i resurseffektivitet
- 2016
-
Ingår i: Dagens Nyheter. - 1101-2447. ; :2016-04-30
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Ny rapport. Det svenska näringslivet kan bli mer hållbart, resurssmart och därmed internationellt konkurrenskraftigt. Men för det behövs en tydlig politisk avsiktsförklaring och riktlinjer. Vi har listat sex områden där policyutveckling brådskar, skriver företrädare för näringsliv, forskning och myndigheter i en gemensam uppmaning.
|
|
| 18. |
- Bergström, Göran, 1964, et al.
(författare)
-
Body weight at age 20 and in midlife is more important than weight gain for coronary atherosclerosis: Results from SCAPIS.
- 2023
-
Ingår i: Atherosclerosis. - : Elsevier BV. - 1879-1484 .- 0021-9150. ; 373, s. 46-54
-
Tidskriftsartikel (refereegranskat)abstract
- Elevated body weight in adolescence is associated with early cardiovascular disease, but whether this association is traceable to weight in early adulthood, weight in midlife or to weight gain is not known. The aim of this study is to assess the risk of midlife coronary atherosclerosis being associated with body weight at age 20, body weight in midlife and body weight change.We used data from 25,181 participants with no previous myocardial infarction or cardiac procedure in the Swedish CArdioPulmonary bioImage Study (SCAPIS, mean age 57 years, 51% women). Data on coronary atherosclerosis, self-reported body weight at age 20 and measured midlife weight were recorded together with potential confounders and mediators. Coronary atherosclerosis was assessed using coronary computed tomography angiography (CCTA) and expressed as segment involvement score (SIS).The probability of having coronary atherosclerosis was markedly higher with increasing weight at age 20 and with mid-life weight (p<0.001 for both sexes). However, weight increase from age 20 until mid-life was only modestly associated with coronary atherosclerosis. The association between weight gain and coronary atherosclerosis was mainly seen in men. However, no significant sex difference could be detected when adjusting for the 10-year delay in disease development in women.Similar in men and women, weight at age 20 and weight in midlife are strongly related to coronary atherosclerosis while weight increase from age 20 until midlife is only modestly related to coronary atherosclerosis.
|
|
| 19. |
- Blom, Elin S, et al.
(författare)
-
Increased mRNA Levels of TCF7L2 and MYC of the Wnt Pathway in Tg-ArcSwe Mice and Alzheimer's Disease Brain
- 2010
-
Ingår i: International journal of Alzheimer's disease. - : Hindawi Limited. - 2090-0252 .- 2090-8024. ; 2011, s. 936580-
-
Tidskriftsartikel (refereegranskat)abstract
- Several components in the Wnt pathway, including β-catenin and glycogen synthase kinase 3 beta, have been implied in AD pathogenesis. Here, mRNA brain levels from five-month-old tg-ArcSwe and nontransgenic mice were compared using Affymetrix microarray analysis. With surprisingly small overall changes, Wnt signaling was the most affected pathway with altered expression of nine genes in tg-ArcSwe mice. When analyzing mRNA levels of these genes in human brain, transcription factor 7-like 2 (TCF7L2) and v-myc myelocytomatosis viral oncogene homolog (MYC), were increased in Alzheimer's disease (AD) (P < .05). Furthermore, no clear differences in TCF7L2 and MYC mRNA were found in brains with frontotemporal lobar degeneration, suggesting that altered regulation of these Wnt-related genes could be specific to AD. Finally, mRNA levels of three neurogenesis markers were analyzed. Increased mRNA levels of dihydropyrimidinase-like 3 were observed in AD brain, suggesting that altered Wnt pathway regulation may signify synaptic rearrangement or neurogenesis.
|
|
| 20. |
|
|
| 21. |
- Burden, Håkan, et al.
(författare)
-
The role of policy labs for introducing autonomous vehicles
- 2021
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper explains the methodological approach of policy labs as used in applied research projects on autonomous vehicles in Sweden. While introducing new technologies we need to ensure that regulations and policies keep up with the fast-paced technological development. Policy labs is one way of managing the perceived conflict between technological innovation and existing regulations. Within a policy lab, a wide range of stakeholders gather to solve the bottlenecks for innovations together. We show through three different R&D projects how the policy lab approach can be applied and which results, improvements and challenges it revealed for introducing autonomous vehicles.
|
|
| 22. |
- Callmer, Jonas, 1981-, et al.
(författare)
-
Silent Localization of Underwater Sensors Using Magnetometers
- 2010
-
Ingår i: EURASIP Journal on Advances in Signal Processing. - : Hindawi Publishing Corporation. - 1687-6172 .- 1687-6180. ; 2010:1
-
Tidskriftsartikel (refereegranskat)abstract
- Sensor localization is a central problem for sensor networks. If the sensor positions are uncertain, the target tracking ability of the sensor network is reduced. Sensor localization in underwater environments is traditionally addressed using acoustic range measurements involving known anchor or surface nodes. We explore the usage of triaxial magnetometers and a friendly vessel with known magnetic dipole to silently localize the sensors. The ferromagnetic field created by the dipole is measured by the magnetometers and is used to localize the sensors. The trajectory of the vessel and the sensor positions are estimated simultaneously using an Extended Kalman Filter (EKF). Simulations show that the sensors can be accurately positioned using magnetometers.
|
|
| 23. |
- Cao, Le Phuong, 1983-
(författare)
-
Optimal Transmit Strategies for Multi-antenna Systems with Joint Sum and Per-antenna Power Constraints
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Nowadays, wireless communications have become an essential part of our daily life. During the last decade, both the number of users and their demands for wireless data have tremendously increased. Multi-antenna communication is a promising solution to meet this ever-growing traffic demands. In this dissertation, we study the optimal transmit strategies for multi-antenna systems with advanced power constraints, in particular joint sum and per-antenna power constraints. We focus on three different models including multi-antenna point-to-point channels, wiretap channels and massive multiple-input multiple-output (MIMO) setups. The solutions are provided either in closed-form or efficient iterative algorithms, which are ready to be implemented in practical systems.The first part is concerned with the optimal transmit strategies for point-to-point multiple-input single-output (MISO) and multiple-input multiple-output (MIMO) channels with joint sum and per-antenna power constraints. For the Gaussian MISO channels, a closed-form characterization of an optimal beamforming strategy is derived. It is shown that we can always find an optimal beamforming transmit strategy that allocates the maximal sum power with phases matched to the complex channel coefficients. An interesting property of the optimal power allocation is that whenever the optimal power allocation of the corresponding problem with sum power constraint only exceeds per-antenna power constraints, it is optimal to allocate maximal per-antenna power to those antennas to satisfy the per-antenna power constraints. The remaining power is distributed among the other antennas whose optimal allocation follows from a reduced joint sum and per-antenna power constraints problem with fewer channel coefficients and a reduced sum power constraint. For the Gaussian MIMO channels, it is shown that if an unconstraint optimal power allocation for an antenna exceeds a per-antenna power constraint, then the maximal power for this antenna is used in the constraint optimal transmit strategy. This observation is then used in an iterative algorithm to compute the optimal transmit strategy in closed-form.In the second part of the thesis, we investigate the optimal transmit strategies for Gaussian MISO wiretap channels. Motivated by the fact that the non-secure capacity of the MISO wiretap channels is usually larger than the secrecy capacity, we study the optimal trade-off between those two rates with different power constraint settings, in particular, sum power constraint only, per-antenna power constraints only, and joint sum and per-antenna power constraints. To characterize the boundary of the optimal rate region, which describes the optimal trade-off between non-secure transmission and secrecy rates, related problems to find optimal transmit strategies that maximize the weighted rate sum with different power constraints are derived. Since these problems are not necessarily convex, equivalent problem formulation is used to derive optimal transmit strategies. A closed-formsolution is provided for sum power constraint only problem. Under per-antenna power constraints, necessary conditions to find the optimal power allocation are provided. Sufficient conditions, however, are available for the case of two transmit antennas only. For the special case of parallel channels, the optimal transmit strategies can deduced from an equivalent point-to-point channel problem. In this case, there is no trade-off between secrecy and non-secrecy rate, i.e., there is onlya transmit strategy that maximizes both rates.Finally, the optimal transmit strategies for large-scale MISO and massive MIMO systems with sub-connected hybrid analog-digital beamforming architecture, RF chain and per-antenna power constraints are studied. The system is configured such that each RF chain serves a group of antennas. For the large-scale MISO system, necessary and sufficient conditions to design the optimal digital and analog precoders are provided. It is optimal that the phase at each antenna is matched tothe channel so that we have constructive alignment. Unfortunately, for the massive MIMO system, only necessary conditions are provided. The necessary conditions to design the digital precoder are established based on a generalized water-filling and joint sum and per-antenna optimal power allocation solution, while the analog precoder is based on a per-antenna power allocation solution only. Further, we provide the optimal power allocation for sub-connected setups based on two properties: (i) Each RF chain uses full power and (ii) if the optimal power allocation of the unconstraint problem violates a per-antenna power constraint then it is optimal to allocate the maximal power for that antenna. The results in the dissertation demonstrate that future wireless networks can achieved higher data rates with less power consumption. The designs of optimal transmit strategies provided in this dissertation are valuable for ongoing implementations in future wireless networks. The insights offered through the analysis and design of the optimal transmit strategies in the dissertation also provide the understanding of the optimal power allocation on practical multi-antenna systems.
|
|
| 24. |
- Charpentier Ljungqvist, Fredrik, 1982-, et al.
(författare)
-
Climatic signatures in early modern European grain harvest yields
- 2023
-
Ingår i: Climate of the Past. - 1814-9324 .- 1814-9332. ; 19:12, s. 2463-2491
-
Tidskriftsartikel (refereegranskat)abstract
- The association between climate variability and grain harvest yields has been an important component of food security and economy in European history. Yet, inter-regional comparisons of climate–yield relationships have been hampered by locally varying data types and the use of different statistical methods. Using a coherent statistical framework, considering the effects of diverse serial correlations on statistical significance, we assess the temperature and hydroclimate (precipitation and drought) signatures in grain harvest yields across varying environmental settings of early modern (ca. 1500–1800) Europe. An unprecedentedly large network of yield records from northern (Sweden), central (Switzerland), and southern (Spain) Europe are compared with a diverse set of seasonally and annually resolved palaeoclimate reconstructions. Considering the effects of different crop types and time series frequencies, we find within regions consistent climate–harvest yield associations characterized by a significant summer soil moisture signal in Sweden, winter temperature and precipitation signals in Switzerland, and spring and annual mean temperature signals in Spain. The regional-scale climate–harvest associations are weaker than the recently revealed climate signals in early modern grain prices but similar in strength to modern climate–harvest relationships at comparable spatial scales. This is a noteworthy finding considering the uncertainties inherent in both historical harvest and palaeoclimate data.
|
|
| 25. |
- Faust, Robin, 1992, et al.
(författare)
-
Role of Surface Morphology on Bed Material Activation during Indirect Gasification of Wood
- 2023
-
Ingår i: Fuel. - : Elsevier. - 0016-2361 .- 1873-7153. ; 333, Part 1
-
Tidskriftsartikel (refereegranskat)abstract
- Olivine and alkali-feldspar were utilized in separate campaigns in an indirect dual fluidized bed gasification campaign with woody biomass as fuel. After three days, both bed materials were reported to be active towards tar removal and exhibited oxygen-carrying abilities and had formed an ash layer consisting of an outer ash deposition layer and an inner interaction layer.X-ray microtomography analysis concluded that a preferred deposition of ash happens onto convex regions of the bed particles, which results in an increase in thickness of the ash layer over convex regions. This effect is most pronounced for the outer layer which is a product of ash deposition. The inner layer exhibits a homogeneous thickness and is probably formed by interaction of Ca from the outer layer with the particles. Transmission electron microscopy revealed the presence of Fe and Mn on the surface of the particles in a solid solution with Mg. The oxygen-carrying effect which is found for aged particles is therefore attributed to the presence of Fe and Mn on the surface of aged particles. Alkali were found on the surface of both particles which are likely contributing to the catalytic activity of the material towards tar removal.
|
|
| 26. |
- Favre-Felix, Antoine, et al.
(författare)
-
Absolute Eye Gaze Estimation With Biosensors in Hearing Aids
- 2019
-
Ingår i: Frontiers in Neuroscience. - : Frontiers Media S.A.. - 1662-4548 .- 1662-453X. ; 13
-
Tidskriftsartikel (refereegranskat)abstract
- People with hearing impairment typically have difficulties following conversations in multi-talker situations. Previous studies have shown that utilizing eye gaze to steer audio through beamformers could be a solution for those situations. Recent studies have shown that in-ear electrodes that capture electrooculography in the ear (EarEOG) can estimate the eye-gaze relative to the head, when the head was fixed. The head movement can be estimated using motion sensors around the ear to create an estimate of the absolute eye-gaze in the room. In this study, an experiment was designed to mimic a multi-talker situation in order to study and model the EarEOG signal when participants attempted to follow a conversation. Eleven hearing impaired participants were presented speech from the DAT speech corpus (Bo Nielsen et al., 2014), with three targets positioned at -30 degrees, 0 degrees and +30 degrees azimuth. The experiment was run in two setups: one where the participants had their head fixed in a chinrest, and the other where they were free to move their head. The participants task was to focus their visual attention on an LED-indicated target that changed regularly. A model was developed for the relative eye-gaze estimation, taking saccades, fixations, head movement and drift from the electrode-skin half-cell into account. This model explained 90.5% of the variance of the EarEOG when the head was fixed, and 82.6% when the head was free. The absolute eye-gaze was also estimated utilizing that model. When the head was fixed, the estimation of the absolute eye-gaze was reliable. However, due to hardware issues, the estimation of the absolute eye-gaze when the head was free had a variance that was too large to reliably estimate the attended target. Overall, this study demonstrated the potential of estimating absolute eye-gaze using EarEOG and motion sensors around the ear.
|
|
| 27. |
- Flygt, Johanna, et al.
(författare)
-
Human Traumatic Brain Injury Results in Oligodendrocyte Death and Increases the Number of Oligodendrocyte Progenitor Cells
- 2016
-
Ingår i: Journal of Neuropathology and Experimental Neurology. - : Oxford University Press (OUP). - 0022-3069 .- 1554-6578. ; 75:6, s. 503-515
-
Tidskriftsartikel (refereegranskat)abstract
- Oligodendrocyte (OL) death may contribute to white matter pathology, a common cause of network dysfunction and persistent cognitive problems in patients with traumatic brain injury (TBI). Oligodendrocyte progenitor cells (OPCs) persist throughout the adult CNS and may replace dead OLs. OL death and OPCs were analyzed by immunohistochemistry of human brain tissue samples, surgically removed due to life-threatening contusions and/or focal brain swelling at 60.6 ± 75 hours (range 4–192 hours) postinjury in 10 severe TBI patients (age 51.7 ± 18.5 years). Control brain tissue was obtained postmortem from 5 age-matched patients without CNS disorders. TUNEL and CC1 co-labeling was used to analyze apoptotic OLs, which were increased in injured brain tissue (p < 0.05), without correlation with time from injury until surgery. The OPC markers Olig2, A2B5, NG2, and PDGFR-α were used. In contrast to the number of single-labeled Olig2, A2B5, NG2, and PDGFR-α-positive cells, numbers of Olig2 and A2B5 co-labeled cells were increased in TBI samples (p < 0.05); this was inversely correlated with time from injury to surgery (r = -0.8, p < 0.05). These results indicate that severe focal human TBI results in OL death and increases in OPCs postinjury, which may influence white matter function following TBI.
|
|
| 28. |
- Frankal, Miriam, 1983, et al.
(författare)
-
Hepatitis E Virus Infection, a Risk for Liver Transplant Recipients in Sweden
- 2022
-
Ingår i: Transplantation Direct. - 2373-8731. ; 8:12
-
Tidskriftsartikel (refereegranskat)abstract
- Background. Following exposure to hepatitis E virus (HEV), liver transplant (LT) recipients have an increased risk of developing chronic infection, which may rapidly progress to severe liver damage if not treated. The prevalence of HEV infection after LT is unclear and likely varies geographically. The aim of this study was to investigate the prevalence of acute and chronic HEV infection among LT recipients in an HEV endemic region. Methods. During 2013 to 2015, 109 of 152 prospectively enrolled patients listed for LT received a liver graft and completed the study protocol. They were evaluated for anti-HEV IgM, HEV IgG, and HEV RNA at the time of LT assessment and 3 and 12 mo post-LT. Medical records were reviewed. Results. Twelve (11%) LT recipients acquired markers of HEV infection during the study period. Seven patients (6%) had detectable HEV RNA, 1 before LT and 3 at the 3-mo and another 3 at the 12-mo follow-up post-LT. All resolved their infections without treatment and had undetectable HEV RNA at the succeeding follow-up. Another 5 (5%) patients developed anti-HEV antibodies without detectable HEV RNA as an indication of HEV infection during follow-up. Signs and symptoms of HEV infection were subtle‚ and none were diagnosed in routine clinical care. Conclusion. A substantial proportion of LT recipients in Sweden are at risk of acquiring HEV infection, both before and after LT. The results highlight the frequency of silent, spontaneously resolving HEV infections and do not support universal screening of LT recipients in Sweden, despite HEV being a potentially treatable infection.
|
|
| 29. |
- Hagstrom, Emil, et al.
(författare)
-
IMPACT OF BODY WEIGHT AT AGE 20 AND WEIGHT GAIN DURING ADULTHOOD ON MIDLIFE CORONARY ARTERY CALCIUM IN 15,000 MEN AND WOMEN : AN INTERIM ANALYSIS OF THE SWEDISH CARDIOPULMONARY BIOIMAGE STUDY
- 2019
-
Ingår i: Journal of the American College of Cardiology. - : ELSEVIER SCIENCE INC. - 0735-1097 .- 1558-3597. ; 73:9, s. 1692-1692
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundElevated body weight in adolescence is strongly associated with early cardiovascular disease, but whether this association is traceable to weight in early adulthood, or to weight gain with subsequent high adult weight is not known. Using data from the Swedish CArdioPulmonary bioImage Study (SCAPIS), we investigated the association between weight at age 20, weight gain to midlife and coronary artery calcium score (CACS) at midlife.MethodsIn the first 15,810 participants in SCAPIS (mean age 58 years, 52% women), data on CACS at midlife, self-reported body weight at age 20 and weight at examination in SCAPIS were recorded.ResultsCACS in midlife was significantly higher with increasing weight at age 20 (p<0.001 for both sexes), and then increased with weight gain until midlife at all levels of body weight at age 20 after adjusting for age, height, smoking, alcohol intake, education level, exercise levels and LDL cholesterol. However, the association with weight gain was only significant in men (p = 0.047), not in women (p=0.474). No significant interaction was seen between weight at age 20 and midlife weight with CACS. The effect of weight at age 20 on CACS was significantly more marked in men than in women, as was the effect of weight gain (p<0.001 for both interactions).ConclusionWeight at age 20 and weight gain to midlife were both related to CACS, but much more markedly so in men than in women, indicating a generally larger effect of both early adult weight and further weight gain until midlife on CACS in men, compared to women.
|
|
| 30. |
- Havervall, Sebastian, et al.
(författare)
-
Robust humoral and cellular immune responses and low risk for reinfection at least 8 months following asymptomatic to mild COVID-19
- 2022
-
Ingår i: Journal of Internal Medicine. - : John Wiley & Sons. - 0954-6820 .- 1365-2796. ; 291:1, s. 72-80
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Emerging data support detectable immune responses for months after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vaccination, but it is not yet established to what degree and for how long protection against reinfection lasts.Methods: We investigated SARS-CoV-2-specific humoral and cellular immune responses more than 8 months post-asymptomatic, mild and severe infection in a cohort of 1884 healthcare workers (HCW) and 51 hospitalized COVID-19 patients. Possible protection against SARS-CoV-2 reinfection was analyzed by a weekly 3-month polymerase chain reaction (PCR) screening of 252 HCW that had seroconverted 7 months prior to start of screening and 48 HCW that had remained seronegative at multiple time points.Results: All COVID-19 patients and 96% (355/370) of HCW who were anti-spike IgG positive at inclusion remained anti-spike IgG positive at the 8-month follow-up. Circulating SARS-CoV-2-specific memory T cell responses were detected in 88% (45/51) of COVID-19 patients and in 63% (233/370) of seropositive HCW. The cumulative incidence of PCR-confirmed SARS-CoV-2 infection was 1% (3/252) among anti-spike IgG positive HCW (0.13 cases per 100 weeks at risk) compared to 23% (11/48) among anti-spike IgG negative HCW (2.78 cases per 100 weeks at risk), resulting in a protective effect of 95.2% (95% CI 81.9%-99.1%).Conclusions: The vast majority of anti-spike IgG positive individuals remain anti-spike IgG positive for at least 8 months regardless of initial COVID-19 disease severity. The presence of anti-spike IgG antibodies is associated with a substantially reduced risk of reinfection up to 9 months following asymptomatic to mild COVID-19.
|
|
| 31. |
- Hermansson, Joel, et al.
(författare)
-
Autonomous Landing of an Unmanned Aerial Vehicle
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This paper is concerned with the problem of autonomously landing an unmanned aerial vehicle (UAV) on a stationary platform. Our solution consists of two parts, a sensor fusion framework producing estimates of the UAV state and a control system that computes appropriate actuator commands. There are three sensors used, a camera, a GPS and a compass. Besides the description of the solution, we also present experimental results illustrating the results obtained in using our system to autonomously land an UAV.
|
|
| 32. |
- Hober, Sophia, Professor, 1965-, et al.
(författare)
-
Systematic evaluation of SARS-CoV-2 antigens enables a highly specific and sensitive multiplex serological COVID-19 assay
- 2021
-
Ingår i: Clinical & Translational Immunology. - : Wiley. - 2050-0068. ; 10:7
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. The COVID-19 pandemic poses an immense need for accurate, sensitive and high-throughput clinical tests, and serological assays are needed for both overarching epidemiological studies and evaluating vaccines. Here, we present the development and validation of a high-throughput multiplex bead-based serological assay. Methods. More than 100 representations of SARS-CoV-2 proteins were included for initial evaluation, including antigens produced in bacterial and mammalian hosts as well as synthetic peptides. The five best-performing antigens, three representing the spike glycoprotein and two representing the nucleocapsid protein, were further evaluated for detection of IgG antibodies in samples from 331 COVID-19 patients and convalescents, and in 2090 negative controls sampled before 2020. Results. Three antigens were finally selected, represented by a soluble trimeric form and the S1-domain of the spike glycoprotein as well as by the C-terminal domain of the nucleocapsid. The sensitivity for these three antigens individually was found to be 99.7%, 99.1% and 99.7%, and the specificity was found to be 98.1%, 98.7% and 95.7%. The best assay performance was although achieved when utilising two antigens in combination, enabling a sensitivity of up to 99.7% combined with a specificity of 100%. Requiring any two of the three antigens resulted in a sensitivity of 99.7% and a specificity of 99.4%. Conclusion. These observations demonstrate that a serological test based on a combination of several SARS-CoV-2 antigens enables a highly specific and sensitive multiplex serological COVID-19 assay.
|
|
| 33. |
- Ingelsson, Martin, et al.
(författare)
-
No alteration in tau exon 10 alternative splicing in tangle-bearing neurons of the Alzheimer's disease brain
- 2006
-
Ingår i: Acta Neuropathologica. - : Springer Science and Business Media LLC. - 0001-6322 .- 1432-0533. ; 112:4, s. 439-449
-
Tidskriftsartikel (refereegranskat)abstract
- Defective splicing of tau mRNA, promoting a shift between tau isoforms with (4R tau) and without (3R tau) exon 10, is believed to be a pathological consequence of certain tau mutations causing frontotemporal dementia. By assessing protein and mRNA levels of 4R tau and 3R tau in 27 AD and 20 control temporal cortex, we investigated whether altered tau splicing is a feature also in Alzheimer's disease (AD). However, apart from an expected increase of sarcosyl-insoluble tau in AD, there were no significant differences between the groups. Next, by laser-capture microscopy and quantitative PCR, we separately analyzed CA1 hippocampal neurons with and without neurofibrillary pathology from six of the AD and seven of the control brains. No statistically significant differences in 4R tau/3R tau mRNA were found between the different subgroups. Moreover, we confirmed the absence of significant ratio differences in a second data set with laser-captured entorhinal cortex neurons from four AD and four control brains. Finally, the 4R tau/3R tau ratio in CA1 neurons was roughly half of the ratio in temporal cortex, indicating region-specific differences in tau mRNA splicing. In conclusion, this study indicated region-specific and possibly cell-type-specific tau splicing but did not lend any support to overt changes in alternative splicing of tau exon 10 being an underlying factor in AD pathogenesis.
|
|
| 34. |
|
|
| 35. |
- Jones, Benjamin L., 1991-, et al.
(författare)
-
Human micronutrient provision by seagrass fisheries outperform coral reefs in a malnourished region
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Blue foods can help tackle hunger by providing rich sources of micronutrients such as calcium, iron, and zinc. Here, we used a novel index of nutrient multifunctionality to assess the micronutrient contributions of fish species across key components of the tropical seascape along a 3000-km stretch of coastline in East Africa. We found that micronutrient multifunctionality varied significantly throughout the tropical seascape, and that the average seagrass-associated fish is more nutritious than a reef-associated fish. The role of seagrass meadows in provisioning high levels of multiple micronutrients relative to coral reefs becomes substantial when we subset the fish communities to include only those species that are high value and targeted in the region. Key fisheries species were far more likely to occur in seagrass meadows than on coral reefs, including those that are both fished and protected, which, when coupled with overall higher per capita micronutrient content, positions seagrass meadows as an unrecognized reservoir of micronutrients to support human health.
|
|
| 36. |
- Karlsson, MariAnne, 1956, et al.
(författare)
-
Patterns of use, perceived benefits and reported effects of access to navigation support systems: an inter-European field operational test
- 2015
-
Ingår i: IET Intelligent Transport Systems. - : Institution of Engineering and Technology (IET). - 1751-9578 .- 1751-956X. ; 9:8, s. 802-809
-
Tidskriftsartikel (refereegranskat)abstract
- The study presents findings regarding drivers' patterns of use, attitude towards, and reported effects of access tomature nomadic navigation support systems. Three different systems were tested by 582 drivers in four-field operationaltests for a period of six months. A majority of the participants used the support system for trips where the route/destination was unfamiliar but there were also other use scenarios. The main benefits entailed convenience andcomfort. Reported effects involved increased possibilities to choose the route according to preferences; a decrease inthe time it took to reach destinations and in the distance covered to reach the destination. One in four reported adecrease in fuel consumption attributed an increased compliance with speed limits and/or that driving around andsearching for the correct route to reach the desired destination could be avoided. A majority reported ‘no change’regarding the number of journeys made by car. Reported effects (whether increases or decreases) were howeversmaller than expected before the trial.
|
|
| 37. |
- Keding, Oskar, et al.
(författare)
-
Coherence Estimation Tracks Auditory Attention in Listeners with Hearing Impairment
- 2023
-
Ingår i: INTERSPEECH 2023. ; , s. 5162-5166
-
Konferensbidrag (refereegranskat)abstract
- Coherence estimation between speech envelope and electroencephalography (EEG) is a proven method in neural speech tracking. This paper proposes an improved coherence estimation algorithm which utilises phase sensitive multitaper cross-spectral estimation. Estimated EEG coherence differences between attended and ignored speech envelopes for a hearing impaired (HI) population are evaluated and compared. Testing was made on 31 HI subjects and showed significant coherence differences for grand averages over the delta, theta, and alpha EEG bands. Significance of increased coherence for attended speech was stronger for the new method compared to the traditional method. The new method of estimating EEG coherence, improves statistical detection performance and enables more rigorous data-based hypothesis-testing results.
|
|
| 38. |
- Kullberg, Anton, et al.
(författare)
-
On the Relationship Between Iterated Statistical Linearization and Quasi-Newton Methods
- 2023
-
Ingår i: IEEE Signal Processing Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1070-9908 .- 1558-2361. ; 30, s. 1777-1781
-
Tidskriftsartikel (refereegranskat)abstract
- This letter investigates relationships between iterated filtering algorithms based on statistical linearization, such as the iterated unscented Kalman filter (IUKF), and filtering algorithms based on quasi-Newton (QN) methods, such as the QN iterated extended Kalman filter (QN-IEKF). Firstly, it is shown that the IUKF and the iterated posterior linearization filter (IPLF) can be viewed as QN algorithms, by finding a Hessian correction in the QN-IEKF such that the IPLF iterate updates are identical to that of the QN-IEKF. Secondly, it is shown that the IPLF/IUKF update can be rewritten such that it is approximately identical to the QN-IEKF, albeit for an additional correction term. This enables a richer understanding of the properties of iterated filtering algorithms based on statistical linearization.
|
|
| 39. |
- Kullberg, Anton, 1993-, et al.
(författare)
-
On the Relationship Between Iterated Statistical Linearization and Quasi–Newton Methods
- 2023
-
Ingår i: IEEE Signal Processing Letters. - : IEEE. - 1070-9908 .- 1558-2361. ; 30, s. 1777-1781
-
Tidskriftsartikel (refereegranskat)abstract
- This letter investigates relationships between iterated filtering algorithms based on statistical linearization, such as the iterated unscented Kalman filter (IUKF), and filtering algorithms based on quasi–Newton (QN) methods, such as the QN iterated extended Kalman filter (QN–IEKF). Firstly, it is shown that the IUKF and the iterated posterior linearization filter (IPLF) can be viewed as QN algorithms, by finding a Hessian correction in the QN –IEKF such that the IPLF iterate updates are identical to that of the QN–IEKF. Secondly, it is shown that the IPLF/ IUKF update can be rewritten such that it is approximately identical to the QN–IEKF, albeit for an additional correction term. This enables a richer understanding of the properties of iterated filtering algorithms based on statistical linearization.
|
|
| 40. |
- Kumpiene, Jurate, et al.
(författare)
-
Phosphorus and cadmium availability in soil fertilized with biosolids and ashes
- 2016
-
Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 151, s. 124-132
-
Tidskriftsartikel (refereegranskat)abstract
- The recycling of hygienized municipal sewage sludge (biosolids) to soil as the source of phosphorus (P) is generally encouraged. The use of biosolids, however, has some concerns, such as the presence of elevated concentrations of potentially toxic trace elements, and the possible presence of pathogens, hormones and antibiotics. Organic substances are destroyed during combustion whereas trace elements could partly be separated from P in different ash fractions. Biomass combustion waste (ash) can instead be considered as an alternative P source. This study evaluates and compares the impact of biosolids and their combustion residues (ashes), when used as fertilizers, on P and Cd solubility in soil, plant growth and plant uptake of these elements. Biosolids were also amended with K and Ca to improve the composition and properties of P in ashes, and incinerated at either 800 °C or 950 °C. Combustion of biosolids improved the Cd/P ratio in ashes by 2–5 times, compared with the initial biosolids. The low Cd content in ashes (4–9 mg Cd (kg P)−1) makes this material a particularly attractive alternative to mineral fertilizers. Significantly higher pore water P (as well as total N) was measured in soils containing biosolids, but plants produced a higher biomass in soil fertilized with ashes. The K and Ca amendments prior to biosolids combustion generally decreased the total Cd in ash, but had little effect on P and Cd uptake and biomass growth. Similarly, the combustion temperature had negligible effect on these factors as well.
|
|
| 41. |
- Luis de la Vara, Jose, et al.
(författare)
-
The AMASS Approach for Assurance and Certification of Critical Systems
- 2019
-
Ingår i: embedded world 2019 ewC-2019.
-
Konferensbidrag (refereegranskat)abstract
- Safety-critical systems are subject to rigorous assurance and certification processes to guarantee that they do not pose unreasonable risks to people, property, or the environment. The associated activities are usually complex and time-consuming, thus they need adequate support for their execution. The activities are further becoming more challenging as the systems are evolving towards open, interconnected systems with new features, e.g. Internet connectivity, and new assurance needs, e.g. compliance with several assurance standards for different dependability attributes. This requires the development of novel approaches for cost-effective assurance and certification. With the overall goal of lowering assurance and certification costs in face of rapidly changing features and market needs, the AMASS project has created and consolidated the de-facto European-wide open solution for assurance and certification of critical systems. This has been achieved by establishing a novel holistic and reuse-oriented approach for architecture-driven assurance, multi-concern assurance, and for seamless interoperability between assurance and engineering activities along with third-party activities. This paper introduces the main elements of the AMASS approach and how to use them and benefit from them.
|
|
| 42. |
- Lundquist, Christian, et al.
(författare)
-
Insights from Implementing a System for Peer-Review
- 2013
-
Ingår i: IEEE Transactions on Education. - 0018-9359 .- 1557-9638. ; 56:3, s. 261-267
-
Tidskriftsartikel (refereegranskat)abstract
- Courses at the Master’s level in automatic control and signal processing cover mathematical theories and algorithms for control, estimation, and filtering. However, giving students practical experience in how to use these algorithms is also an important part of these courses. A goal is that the students should not only be able to understand and derive these algorithms, but also be able to apply them to real-life technical problems. The latter is achieved by assigning more time to the laboratory tutorials and designing them in such a way that the exercises are open for interpretation; an example of this would be giving the students more freedom to decide how to acquire the data needed to solve the given exercises.The students are asked to hand in a laboratory report in which they describe how they solved the exercises. This paper presents a double-blind peer-review process for laboratory reports, introduced at the Department of Electrical Engineering, Linköping University, Sweden. A survey was administered to students, and the results are summarized in this paper. Also discussed are the teachers’ experiences of peer review and of how students perform later in their education in writing their Master’s theses.
|
|
| 43. |
|
|
| 44. |
|
|
| 45. |
- Mohamad, Mazen, et al.
(författare)
-
Cybersecurity Pathways Towards CE-Certified Autonomous Forestry Machines
- 2024
-
Ingår i: arXiv.
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- he increased importance of cybersecurity in autonomous machinery is becoming evident in the forestry domain. Forestry worksites are becoming more complex with the involvement of multiple systems and system of systems. Hence, there is a need to investigate how to address cybersecurity challenges for autonomous systems of systems in the forestry domain. Using a literature review and adapting standards from similar domains, as well as collaborative sessions with domain experts, we identify challenges towards CE-certified autonomous forestry machines focusing on cybersecurity and safety. Furthermore, we discuss the relationship between safety and cybersecurity risk assessment and their relation to AI, highlighting the need for a holistic methodology for their assurance.
|
|
| 46. |
|
|
| 47. |
- Nilsson, Daniel, 1973, et al.
(författare)
-
[New possibilitys in surgery for brain tumors with intraoperative MRI]. : Intraoperativ MRT ger nya möjligheter för neurokirurgi.
- 2019
-
Ingår i: Läkartidningen. - 1652-7518. ; 116
-
Tidskriftsartikel (refereegranskat)abstract
- In surgery for brain tumors, the main challenge is to resect the tumor completely without causing injury to surrounding structures. Intraoperative MRI can provide updated information on remaining tumor and the relationship to critical brain structures. We report our initial experiences from an intraoperative 3 T MRI suite from a surgical, radiological and anesthesiological perspective. The technique has been useful in treating pediatric brain tumor patients, pituitary tumors, low-grade gliomas and epilepsy surgery patients. Image quality has been comparable to conventional diagnostic MRI and there have been no adverse events from the technique. Team-based training and simulation are key factors to manage this complex technical environment and make intraoperative MRI into a routine procedure.
|
|
| 48. |
- Nilsson, M., et al.
(författare)
-
Indoor positioning using multi-frequency RSS with foot-mounted INS
- 2014
-
Ingår i: IPIN 2014 - 2014 International Conference on Indoor Positioning and Indoor Navigation. - : IEEE conference proceedings. - 9781467380546 ; , s. 177-186
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a system which combines a zero-velocity-update-(ZUPT-)aided inertial navigation system (INS), using a foot-mounted inertial measurement unit (IMU), with opportunistic use of multi-frequency received signal strength (RSS) measurements. The system does not rely on maps or pre-collected data from surveys of the radio-frequency (RF) environment. Instead it builds its own database of collected RSS measurements during the course of the operation. New RSS measurements are continuously compared with the stored values in the database, and when the user returns to a previously visited area this can thus be detected. This enables loop-closures to be detected online and used for error drift correction. The system utilises a distributed particle simultaneous localization and mapping (DP-SLAM) algorithm which provides a flexible 2D navigation platform that can be extended with more sensors. The experimental results presented in this paper indicates that the developed RSS SLAM algorithm can, in many cases, significantly improve the positioning performance of a foot-mounted INS.
|
|
| 49. |
- Nyqvist, Hanna E., et al.
(författare)
-
Pose Estimation Using Monocular Vision and Inertial Sensors Aided with Ultra Wide Band
- 2015
-
Ingår i: International Conference on Indoor Positioning and Indoor Navigation (IPIN), 2015. - : IEEE. - 9781467384025 - 9781467384018
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a method for global pose estimation using inertial sensors, monocular vision, and ultra wide band (UWB) sensors. It is demonstrated that the complementary characteristics of these sensors can be exploited to provide improved global pose estimates, without requiring the introduction of any visible infrastructure, such as fiducial markers. Instead, natural landmarks are jointly estimated with the pose of the platform using a simultaneous localization and mapping framework, supported by a small number of easy-to-hide UWB beacons with known positions. The method is evaluated with data from a controlled indoor experiment with high precision ground truth. The results show the benefit of the suggested sensor combination and suggest directions for further work.
|
|
| 50. |
- Raghavan, Maanasa, et al.
(författare)
-
The genetic prehistory of the New World Arctic
- 2014
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 345:6200, s. 1020-
-
Tidskriftsartikel (refereegranskat)abstract
- The New World Arctic, the last region of the Americas to be populated by humans, has a relatively well-researched archaeology, but an understanding of its genetic history is lacking. We present genome-wide sequence data from ancient and present-day humans from Greenland, Arctic Canada, Alaska, Aleutian Islands, and Siberia. We show that Paleo-Eskimos (similar to 3000 BCE to 1300 CE) represent a migration pulse into the Americas independent of both Native American and Inuit expansions. Furthermore, the genetic continuity characterizing the Paleo-Eskimo period was interrupted by the arrival of a new population, representing the ancestors of present-day Inuit, with evidence of past gene flow between these lineages. Despite periodic abandonment of major Arctic regions, a single Paleo-Eskimo metapopulation likely survived in near-isolation for more than 4000 years, only to vanish around 700 years ago.
|
|
