824 research outputs found
A computational method for key-performance-indicator-based parameter identification of industrial manipulators
We present a novel derivative-based parameter identification method to improve the precision at the tool center point of an industrial manipulator. The tool center point is directly considered in the optimization as part of the problem formulation as a key performance indicator. Additionally, our proposed method takes collision avoidance as special nonlinear constraints into account and is therefore suitable for industrial use. The performed numerical experiments show that the optimum experimental designs considering key performance indicators during optimization achieve a significant improvement in comparison to other methods. An improvement in terms of precision at the tool center point of 40% to 44% was achieved in experiments with three KUKA robots and 90 notional manipulator models compared to the heuristic experimental designs chosen by an experimenter as well as 10% to 19% compared to an existing state-of-the-art method
The 5G Localisation Waveform
Todays cellular networks have distinct services that
come with different requirements, figures of merit, etc. for each
application. A communication service such as voice communication
relies on latency better than 150 ms and bit error rates
lower than 1
Waveform Parameter Selection for ITS Positioning
In this paper, we investigate the performance of
mobile vehicle positioning based on signal propagation delay
estimation in the uplink case for a realistic propagation environment.
In order to optimize the ranging performance, we
introduce a parametric waveform. This waveform contains a
scalar parameter for adjusting the distribution of the available
signal power over the frequency. The optimization is achieved
by a functional dependency between the waveform parameter
and the positioning error. In order to derive a cost function,
we combine the approaches of the Cramér-Rao and Ziv-Zakai
bounds for position and propagation delay estimation. As an
exemplary environment we consider a mobile vehicle located in
an area surrounded by three base stations together with realistic
propagation conditions provided by the WINNER II channel
model. The results show that the waveform parameter has to be
adjusted differently compared to a simple free space propagation
scenario. Additionally, we compare the obtained results with a
scenario with four base stations and a scenario where we use
the WINNER II channel model in terms of line-of-sight received
power and shadow fading to classify the effects of geometry and
propagation conditions
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Motion artefact detection in structured illumination microscopy for live cell imaging
The reconstruction process of structured illumination microscopy (SIM) creates substantial artefacts if the specimen has moved during the acquisition. This reduces the applicability of SIM for live cell imaging, because these artefacts cannot always be recognized as such in the final image. A movement is not necessarily visible in the raw data, due to the varying excitation patterns and the photon noise. We present a method to detect motion by extracting and comparing two independent 3D wide-field images out of the standard SIM raw data without needing additional images. Their difference reveals moving objects overlaid with noise, which are distinguished by a probability theory-based analysis. Our algorithm tags motion-artefacts in the final high-resolution image for the first time, preventing the end-user from misinterpreting the data. We show and explain different types of artefacts and demonstrate our algorithm on a living cell
What is the role of Swiss domestic cats in environmental contamination with Echinococcus multilocularis eggs?
Background
The role of the domestic cat as definitive host for Echinococcus multilocularis and thus in environmental contamination with eggs has not yet been entirely resolved. This study aimed to assess the prevalence of E. multilocularis and other gastrointestinal parasites in Swiss domestic cats and to compare the diagnostic sensitivity of different methods for the detection of intestinal taeniid infection.
Methods
Faecal samples from 146 cats were included in the study. Faecal samples only were available from 55 cats; for the other 91 cats, necropsy was performed in addition to faecal sample testing. All (n = 146) faecal samples were analysed by a combined sedimentation/flotation technique (44% ZnCl2) and by the sodium acetate-acetic acid-formalin (SAF) sedimentation technique; when sufficient material was available (n = 121 samples) the Baermann-Wetzel technique was also used. Additionally, all samples were analysed by two coproantigen (copro)-quantitative PCRs (qPCR): (i) a multiplex qPCR able to detect and differentiate between E. multilocularis, Echinococcus granulosus sensu lato and Taenia spp./other cestodes (CEST-qPCR) and (ii) an E. multilocularis-specific qPCR (EM-qPCR). Finally, the intestines were examined macroscopically and microscopically for parasite stages at necropsy (n = 91) and using an intestinal scraping technique (IST) (n = 64).
Results
Of the 146 cats examined, 24 (17.1%) were infected by intestinal parasites, namely Hydatigera (syn. Taenia) taeniaeformis (8.9%), Toxocara cati (6.1%), Capillaria sp. (3.4%), hookworms (3.4%), Mesocestoides litteratus (1.4%), Giardia sp. (1.4%), Cystoisospora rivolta (1.4%), Cystoisospora felis (0.7%), Toxoplasma gondii (0.7%), Hammondia hammondi (0.7%) and Strongyloides sp. (0.7%). Necropsy and the IST revealed adult H. taeniaeformis in 12 animals, of which eight faecal samples were positive by the CEST-qPCR (sensitivity = 67%) and six samples by the sedimentation/flotation technique (sensitivity = 50%). No E. multilocularis infection was detected in the sampled cats. Using Bayesian latent class analysis, the mean posterior prevalence probability was 0.0% (95% confidence interval 0–0.83%) for E. multilocularis.
Conclusions
There was no evidence of E. multilocularis infection among the 146 cats examined, suggesting that the prevalence of this parasite is low (< 1%) in the Swiss domestic cat population. Nonetheless, some of the sampled cats were infected by parasites that have rodents as intermediate hosts, demonstrating successful predation by these cats, and some were infected with zoonotic parasites. Cats therefore should not be disregarded as potential hosts for E. multilocularis and other zoonotic parasites
In vitro validation of a hand-held optical reflectometer to measure clinically observed erosive tooth wear
In this study, we analyzed a newly developed optical reflectometer for measuring erosive tooth wear (ETW) in vitro. Three examiners independently assessed the labial surface of 80 deciduous canines and 75 permanent incisors. One examiner performed visual examinations (BEWE), and the other two used the optical pen-size reflectometer to measure surface reflection intensity (SRI) on the same labial surfaces. The examinations were made in duplicate with at least 1 week interval. Intra- and inter-rater agreements were calculated using weighted kappa analysis for BEWE, and intra-class correlation coefficients (ICC) as well as Bland-Altman plots for SRI. The teeth were separated into without (BEWE 0) or with (BEWE 1-3) ETW, and SRI cut-off points were calculated. Intra-rater agreement for the visual examination was 0.46 and 0.82 for deciduous and permanent teeth, respectively. Inter-rater and intra-rater agreement for SRI were good (ICC > 0.7; p < 0.001). SRI measurements produced high specificity values for deciduous and permanent teeth (≥0.74 and ≥ 0.84, respectively), and lower sensitivity values (≥0.37 and ≥ 0.64, respectively), but permanent teeth had generally higher SRI values (p < 0.05). We observed a significant association between BEWE and SRI (p < 0.05). The optical pen-size reflectometer was able to adequately differentiate ETW on permanent teeth, with highly reliable and reproducible measurements, but ETW on deciduous teeth was less accurately differentiated. The reflectometer is a good candidate for clinical research
Trends and patterns in the public awareness of palliative care, euthanasia, and end-of-life decisions in 3 central european countries using big data analysis from google: retrospective analysis
BackgroundEnd-of-life decisions, specifically the provision of euthanasia and assisted suicide services, challenge traditional medical and ethical principles. Austria and Germany have decided to liberalize their laws restricting assisted suicide, thus reigniting the debate about a meaningful framework in which the practice should be embedded. Evidence of the relevance of assisted suicide and euthanasia for the general population in Germany and Austria is limited.
ObjectiveThe aim of this study is to examine whether the public awareness documented by search activities in the most frequently used search engine, Google, on the topics of palliative care, euthanasia, and advance health care directives changed with the implementation of palliative care services and new governmental regulations concerning end-of-life decisions.
MethodsWe searched for policies, laws, and regulations promulgated or amended in Austria, Germany, and Switzerland between 2004 and 2020 and extracted data on the search volume for each search term topic from Google Trends as a surrogate of public awareness and interest. Annual averages were analyzed using the Joinpoint Regression Program.
ResultsImportant policy changes yielded significant changes in search trends for the investigated topics. The enactment of laws regulating advance health care directives coincided with a significant drop in the volume of searches for the topic of euthanasia in all 3 countries (Austria: −24.48%, P=.02; Germany: −14.95%, P<.001; Switzerland: −11.75%, P=.049). Interest in palliative care increased with the availability of care services and the implementation of laws and policies to promote palliative care (Austria: 22.69%, P=.01; Germany: 14.39, P<.001; Switzerland: 17.59%, P<.001). The search trends for advance health care directives showed mixed results. While interest remained steady in Austria within the study period, it increased by 3.66% (P<.001) in Switzerland and decreased by 2.85% (P<.001) in Germany.
ConclusionsOur results demonstrate that legal measures securing patients’ autonomy at the end of life may lower the search activities for topics related to euthanasia and assisted suicide. Palliative care may be a meaningful way to raise awareness of the different options for end-of-life care and to guide patients in their decision-making process regarding the same
Generalized inverse mean curvature flows in spacetime
Motivated by the conjectured Penrose inequality and by the work of Hawking,
Geroch, Huisken and Ilmanen in the null and the Riemannian case, we examine
necessary conditions on flows of two-surfaces in spacetime under which the
Hawking quasilocal mass is monotone. We focus on a subclass of such flows which
we call uniformly expanding, which can be considered for null as well as for
spacelike directions. In the null case, local existence of the flow is
guaranteed. In the spacelike case, the uniformly expanding condition leaves a
1-parameter freedom, but for the whole family, the embedding functions satisfy
a forward-backward parabolic system for which local existence does not hold in
general. Nevertheless, we have obtained a generalization of the weak
(distributional) formulation of this class of flows, generalizing the
corresponding step of Huisken and Ilmanen's proof of the Riemannian Penrose
inequality.Comment: 21 pages, 1 figur
PEDANT covers all complete RefSeq genomes
The PEDANT genome database provides exhaustive annotation of nearly 3000 publicly available eukaryotic, eubacterial, archaeal and viral genomes with more than 4.5 million proteins by a broad set of bioinformatics algorithms. In particular, all completely sequenced genomes from the NCBI's Reference Sequence collection (RefSeq) are covered. The PEDANT processing pipeline has been sped up by an order of magnitude through the utilization of precalculated similarity information stored in the similarity matrix of proteins (SIMAP) database, making it possible to process newly sequenced genomes immediately as they become available. PEDANT is freely accessible to academic users at http://pedant.gsf.de. For programmatic access Web Services are available at http://pedant.gsf.de/webservices.jsp
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