195 research outputs found

    Comparative Evaluation of Investigation Methods for Estimating the Load-Dependent State of Charge and End of Discharge of a Multirotor UAV Battery

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    As the scope of multirotor unmanned aerial vehicle (UAV) applications increases, more attention is being paid to UAV energy requirements, which vary depending on the mission profile. To obtain accurate information about the UAV battery during flight, the idea of a digital twin including a battery state estimation model is promising. For battery state estimation, a Kalman filter combination is the preferred approach in the literature. Comparing different Kalman filters, the unscented Kalman filter has a more accurate estimation for nonlinear systems compared to the extended Kalman filter. In the application of UAV flight with load-dependent flight missions, the comparison of different Kalman filter estimation methods has not yet been researched. In order to evaluate the applicability of different state of charge estimation methods applied to different UAV flight missions, an extended Kalman filter, an unscented Kalman filter, and the Coulomb-counting method are implemented in this research and combined with an end of discharge estimation. To compare the estimation methods based on a delivery mission and a facade inspection mission, a parameter identification of the UAV battery is performed, and an equivalent circuit model is developed and combined with the estimation methods to estimate the battery state. The results of the investigation show that the unscented Kalman filter achieves more accurate state of charge estimation results than the extended Kalman filter, even in the field of UAV application. The results also show that the choice of estimation method is mainly influenced by the accuracy of the parameter identification process, while the dynamic load of a UAV mission has less impact. Contrarily, the end of discharge estimation does not correlate with the accuracy of the state of charge estimation, indicating that the end of discharge estimation is more dependent on the dynamic load

    Oceanic heat advection to the Arctic in the last Millennium

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    EGU2011-8738 At present, the Arctic is responding faster to global warming than most other areas on earth, as indicated by rising air temperatures, melting glaciers and ice sheets and a decline of the sea ice cover. As part of the meridional overturning circulation which connects all ocean basins and influences global climate, northward flowing Atlantic Water is the major means of heat and salt advection towards the Arctic where it strongly affects the sea ice distribution. Records of its natural variability are critical for the understanding of feedback mechanisms and the future of the Arctic climate system, but continuous historical records reach back only ca. 150 years. To reconstruct the history of temperature variations in the Fram Strait Branch of the Atlantic Current we analyzed a marine sediment core from the western Svalbard margin. In multidecadal resolution the Atlantic Water temperature record derived from planktic foraminifer associations and Mg/Ca measurements shows variations corresponding to the well-known climatic periods of the last millennium (Medieval Climate Anomaly, Little Ice Age, Modern/Industrial Period). We find that prior to the beginning of atmospheric CO2 rise at ca. 1850 A.D. average summer temperatures in the uppermost Atlantic Water entering the Arctic Ocean were in the range of 3-4.5°C. Within the 20th century, however, temperatures rose by ca. 2°C and eventually reached the modern level of ca. 6°C. Such values are unprecedented in the 1000 years before and are presumably linked to the Arctic Amplification of global warming. Taking into account the ongoing rise of global temperatures, further warming of inflowing Atlantic Water is expected to have a profound influence on sea ice and air temperatures in the Arctic

    Development of a framework and the content for a psychoeducational internet-delivered intervention for women after treatment for gynaecological cancer

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    This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).The number of women treated for gynecological cancer is increasing. At the same time, the duration of in-patient hospitalization has decreased, and follow-up with its primary focus on early recognition of recurrence does not meet all patients’ needs. One method of follow-up may be digital intervention. This study describes the development of a psychoeducational Internetdelivered intervention targeting women’s psychosocial needs during the follow-up period after treatment for gynecological cancer. The project consisted of three phases following the UK Medical Research Council Framework guidelines for the development of complex interventions. Phase one identified the evidence in the field, phase two identified the relevant theoretical framework, and phase three included a two-year work process including focus group interviews and think aloud interviews with users. Through the steps of literature review, theoretical framework, and an iterative development process with users and other stakeholders, a six-week program was developed. The program included psychoeducational information, multimedia, exercises, and weekly telephone follow-up with a dedicated nurse. This Internet-delivered intervention can be a novel method for addressing the gap in the provision of follow-up for women after treatment for gynecological cancer.publishedVersio

    CSF neurofilament light chain predicts 10-year clinical and radiologic worsening in multiple sclerosis

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    Background Neurofilament light chain (NfL) is an attractive biomarker of disease activity and progression in MS, but there is a lack in long-term prognostic data. Objective To test the long-term clinical and radiological prognostic value of cerebrospinal fluid (CSF)-NfL among newly diagnosed patients with MS. Methods Newly diagnosed MS patients where followed prospectively with baseline CSF-NfL and repeated MRI and clinical assessments for up to 10 years. Associations between baseline CSF-NfL and longitudinal MRI and clinical assessments were found by Generalized Estimating Equations analysis. Results Forty-two participants were included. CSF-NfL at baseline was significantly associated with the rate of atrophy in globus pallidus (p = 0.009) and hippocampus (p = 0.001) as evaluated by MRI. Baseline volumes of thalamus (β −0.33; 95% CI −0.57 to −0.10, p = 0.006), T1 (β 0.28; 95% CI 0.11 to 0.44, p = 0.001) and T2 (β 0.16; 95% CI 0.04 to 0.27, p = 0.008) lesions and baseline levels of CSF-NfL (β 0.9; 95% CI 0.3 to 1.5, p = 0.002) significantly predicted EDSS worsening over 10 years. Baseline CSF-NfL gave a comparable prediction to the best MRI volumetric predictors. Conclusion CSF-NfL predicted the clinical and radiological course of newly diagnosed patients with MS over a 10-year period, underlining its prognostic role.publishedVersio

    A predictive model for bone marrow disease in cytopenia based on noninvasive procedures

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    Bone marrow specimens are the core of the diagnostic workup of patients with cytopenia. To explore whether next-generation sequencing (NGS) could be used to rule out malignancy without bone marrow specimens, we incorporated NGS in a model to predict presence of disease in the bone marrow of patients with unexplained cytopenia. We analyzed the occurrence of mutations in 508 patients with cytopenia, referred for primary workup of a suspected hematologic malignancy from 2015 to 2020. We divided patients into a discovery (n = 340) and validation (n = 168) cohort. Targeted sequencing, bone marrow biopsy, and complete blood count were performed in all patients. Mutations were identified in 267 (53%) and abnormal bone marrow morphology in 188 (37%) patients. Patients with isolated neutropenia had the lowest frequency of both mutations (21%) and abnormal bone marrow morphology (5%). The median number of mutations per patient was 2 in patients with abnormal bone marrow morphology compared with 0 in patients with a nondiagnostic bone marrow morphology (P < .001). In a multivariable logistic regression, mutations in TET2, SF3B1, U2AF1, TP53, and RUNX1 were significantly associated with abnormal bone marrow morphology. In the validation cohort, a model combining mutational status and clinical data identified 34 patients (20%) without abnormal bone marrow morphology with a sensitivity of 100% (95% confidence interval: 93%-100%). Overall, we show that NGS combined with clinical data can predict the presence of abnormal bone marrow morphology in patients with unexplained cytopenia and thus can be used to assess the need of a bone marrow biopsy

    Automated detection of Diabetic Retinopathy in Three European Populations

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    Objective: Currently 1/12 of the world’s population has diabetes mellitus (DM), many are or will be screened by having retinal images taken. This current study aims to compare the DAPHNE software’s ability to detect DR in three different European populations compared to human grading carried out at the Moorfields Eye Hospital Reading Centre (MEHRC). Participants: Retinal images were taken from participants of the HAPIEE study (Lithuania, n=1014), the PAMDI study (Italy, n=882) and the MARS study (Germany, n=909). Methods: All anonymized images were graded by human graders at MEHRC for the presence of DR. Independently, and without any knowledge of the human grader’s results, the DAPHNE software analysed the images and divided the participants into DR and no-DR groups. Main outcome measures: The primary outcomes were sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the DAPHNE software with regards to the identification of DR or no-DR on retinal images as compared to the human grader as reference standard. Results: A total of 2805 participants were enrolled from the three study sites. The sensitivity of the DAPHNE software was above 93% in all three studies specificity was above 80%, the PPV was above 28% and the NPV was not below 98.8% in any of the studies. The DAPHNE software did not miss any vision-threatening DR. The areas under the curve (AUC) for all three studies were above 0.96. DAPHNE reduced manual human workload by 70% but had a total false positive rate of 63%. Conclusions: The DAPHNE software showed to be reliable to detect DR on three different European populations, using three different imaging settings. Further testing is required to see scalability, performance on live DR screening systems and on camera settings different to these studies

    Børn i udsatte positioner i implementeringen af Den styrkede pÌdagogiske lÌreplan: Et pÌdagogisk dilemma flytter med

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    The strengthened pedagogical curriculum is by various parties presented as a movement away from a narrow focus on educational output with measurements of children’s progress and capabilities. Because of this, accompanying legal frameworks contains a distancing to criticized time-consuming documentation requirements set for day care professionals’ work. However, before as well as after the legislative change, municipal administrations of day care have an obligation to secure measures towards children in vulnerable positions. In this study, we examine the implementation of the strengthened pedagogical curriculum in four municipalities, with a focus on municipal decisions in regards to children in vulnerable positions. The main conclusion is that all municipalities choose to maintain tools to measure and describe all children’s learning and progress, and that this is done with reference to children in vulnerable positions. The study discusses a basic pedagogical dilemma between, on the one hand, making individual children’s challenges visible – and thus risking that children will be met by focus at their deficiency. And, on the other hand, refraining from pointing out challenges – and, because of that, risking that special needs will not be met and competencies needed in school and life will not be sufficiently developed

    Characterization of Eight Novel Spiroleptosphols from Fusarium avenaceum

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    Chemical analyses of Fusarium avenaceum grown on banana medium resulted in eight novel spiroleptosphols, T1, T2 and U&ndash;Z (1&ndash;8). The structures were elucidated by a combination of high-resolution mass spectrometric data and 1- and 2-D NMR experiments. The relative stereochemistry was assigned by 1H coupling and NOESY/ROESY experiments. Absolute stereochemistry established for 7 by vibrational circular dichroism was found analogous to that of the putative polyketide spiroleptosphol from Leptosphaeria doliolum
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