1,236 research outputs found
Modeling WLAN Received Signal Strengths Using Gaussian Process Regression on the Sodindoorloc Dataset
While any wireless technology can be used for indoor localization purposes, WLANhas the advantage of having a huge existing infrastructure. A radio map that matches specific locations to received signal strength is needed, to enable most of these indoor localization methods. To create these radio maps, with enough detail to achieve sufficient localization accuracy, is expensive and time consuming. Therefore, methods to interpolate and extrapolate more detailed maps from sparse radio maps are being developed. One recent approach is to use Gaussian process regression. Even though some papers already studied Gaussian process regression, most studied only the basic model with zero mean and squared exponential kernel. In addition, when the model fit was evaluated in more detail, the experimental area was of limited complexity. Hence, this thesis evaluates the fit of Gaussian process regression, in a more complex indoor environment, based on adequate model metrics and analysis of the plots of the predicted mean and standard deviation functions. As a conclusion, the most suitable model is presented, as well as the reasoning why it was chosen
New data on direct ion storage dosemeters
The DIS-1 dosemeter from the Finnish company RADOS is an innovative kind of passive electronic dosemeter for photon and beta radiation. This study examines the ‘long-term' linear response behaviour, the calibration and readout accuracy with large samples of ‘used' DIS-1 dosemeters especially in the low-dose region, which is of special interest for radiation protection issues. Our measurements prove the adequacy of the DIS-1 dosemeter for long-term-personal dosimetry. The fast and precise readout seems to make the DIS-1 dosemeter an ideal choice for personal dosimetry in low-dose environment
Nuclear stopping and flow in heavy ion collisions and the in-medium NN cross section
We present transport calculations for heavy ion reactions in which the mean
field and the in-medium nucleon-nucleon cross section are consistently based on
the same effective interaction, i.e. the in-medium T-matrix from microscopic
Dirac-Brueckner calculations. Doing so, the stopping in central reactions in
terms of the recently proposed observable and the correlation to
the behavior of the directed flow is investigated. The relation to the nuclear
shear viscosity is discussed.Comment: 9 pages, 4 figure
HySpecNet-11k: A Large-Scale Hyperspectral Dataset for Benchmarking Learning-Based Hyperspectral Image Compression Methods
The development of learning-based hyperspectral image compression methods has
recently attracted great attention in remote sensing. Such methods require a
high number of hyperspectral images to be used during training to optimize all
parameters and reach a high compression performance. However, existing
hyperspectral datasets are not sufficient to train and evaluate learning-based
compression methods, which hinders the research in this field. To address this
problem, in this paper we present HySpecNet-11k that is a large-scale
hyperspectral benchmark dataset made up of 11,483 nonoverlapping image patches.
Each patch is a portion of 128 128 pixels with 224 spectral bands and
a ground sample distance of 30 m. We exploit HySpecNet-11k to benchmark the
current state of the art in learning-based hyperspectral image compression by
focussing our attention on various 1D, 2D and 3D convolutional autoencoder
architectures. Nevertheless, HySpecNet-11k can be used for any unsupervised
learning task in the framework of hyperspectral image analysis. The dataset,
our code and the pre-trained weights are publicly available at
https://hyspecnet.rsim.berlinComment: Accepted at IEEE International Geoscience and Remote Sensing
Symposium (IGARSS) 2023. The dataset, our code and the pre-trained weights
are publicly available at https://hyspecnet.rsim.berli
Asymmetric Colliding Nuclear Matter Approach in Heavy Ion Collisions
The early stage of a heavy ion collision is governed by local non-equilibrium
momentum distributions which have been approximated by colliding nuclear matter
configurations, i.e. by two Lorentz elongated Fermi ellipsoids. This approach
has been extended from the previous assumption of symmetric systems to
asymmetric 2-Fermi sphere configurations, i.e. to different densities. This
provides a smoother transition from the limiting situation of two
interpenetrating currents to an equilibrated system. The model is applied to
the dynamical situations of heavy ion collisions at intermediate energies
within the framework of relativistic transport (RBUU) calculations. We find
that the extended colliding nuclear matter approach is more appropriate to
describe collective reaction dynamics in terms of flow observables, in
particular, for the elliptic flow at low energies.Comment: 21 pages, 8 figures, accepted for publication in Nuclear Physics
Informatik- und Workflow-Aspekte des Digitalisierungsprojektes e-rara.ch
E-rara.ch ist ein Digitalisierungs- und Publikationsprojekt des Schweizer Innovations- und Kooperationsprogramms "E-lib.ch: Elektronische Bibliothek Schweiz" und dient der Digitalisierung und Web-Publikation von alten Drucken aus Schweizer Bibliotheken. Einen ersten inhaltlichen Schwerpunkt bilden dabei die Schweizer Drucke des 16. Jahrhunderts. Es handelt sich um ein gemeinschaftliches Projekt der Universitätsbibliotheken von Basel und Bern, der Bibliothèque de Genève sowie der Zentralbibliothek und der ETH-Bibliothek in Zürich. Neben einem umfangreichen Mengengerüst von über 2 Mio. zu digitalisierenden Seiten und der Datenmenge von bis zu 50 TB hat das Projekt vor allem hinsichtlich des Workflows komplexe Anforderungen. Die Digitalisierung und spätere strukturelle Erschließung der Titel erfolgt dezentral bei den Projektpartnern, während der gesamte technische Betrieb, der Datenimport, der automatisierte Zugriff auf mehrere Kataloge und die Bereitstellung von Archivdateien zentral in der ETH-Bibliothek stattfindet. Die Web-Präsentation des Bestandes erfolgt in einem gemeinschaftlichen Auftritt, kann aber nach den jeweiligen Projektpartnern und nach Kollektionen differenziert werden.
Animetra war für die Leitung des mittlerweile abgeschlossenen IT-Teilprojektes zuständig, in dessen Rahmen eine Evaluation, Beschaffung und Einführung einer geeigneten IT-Plattform durchgeführt wurde. Desweiteren mussten Standards und Abläufe entwickelt und umgesetzt werden, die die gemeinsame Arbeit mit der Plattform, die Datenkommunikation, die Konfiguration sowie die Ergebnisformate für einen konsistenten Datenaufbau definierten. Im Rahmen des Vortrags werden das Evaluationsvorgehen sowie die Workflowlösung vorgestellt und erste Erfahrungswerte präsentiert
Do patients with gastroesophageal reflux disease and somatoform tendencies benefit from antireflux surgery?
Source at http://dx.doi.org/10.3748/wjg.v25.i3.388.BACKGROUND - The clinical presentation of gastroesophageal reflux disease (GERD) shows a large symptom variation also in different intensities among patients. As several studies have shown, there is a large overlap in the symptomatic spectrum between proven GERD and other disorders such as dyspepsia, functional heartburn and/or somatoform disorders.
AIM - To prospectively evaluate the GERD patients with and without somatoform disorders before and after laparoscopic antireflux surgery.
METHODS - In a tertiary referral center for foregut surgery over a period of 3 years patients with GERD, qualifying for the indication of laparoscopic antireflux surgery, were investigated prospectively regarding their symptomatic spectrum in order to identify GERD and associated somatoform disorders. Assessment of symptoms was performed by an instrument for the evaluation of somatoform disorders [Somatoform Symptom Index (SSI) > 17]. Quality of life was evaluated by Gastrointestinal Quality of Life Index (GIQLI).
RESULTS - In 123 patients an indication for laparoscopic antireflux surgery was established and in 43 patients further medical therapy was suggested. The portion of somatoform tendencies in the total patient population was 20.48% (34 patients). Patients with a positive SSI had a preoperative GIQLI of 77 (32-111). Patients with a normal SSI had a GIQLI of 105 (29-140) (P P < 0.0043).
CONCLUSION - Patients with GERD and associated somatoform disorders have significantly worse levels of quality of life. The latter patients can also benefit from laparoscopic fundoplication, however they will not reach a normal level
Gastrointestinal Quality of Life in Gastroesophageal Reflux Disease: A Systematic Review
Background: The Gastrointestinal Quality of Life Index (GIQLI) is a well-established instrument for the assessment of quality of life (QOL) in gastrointestinal (GI) diseases. The purpose of this literature review was to investigate QOL by means of GIQLI in patients with gastroesophageal reflux disease (GERD) prior to any interventional therapy. There are several reports on GIQLI data; however, comparisons from different countries and/or different GERD cohorts assessing the same disease have to date not been conducted. Methods: The GIQLI uses 36 items around 5 dimensions (GI symptoms [19 items], emotional dimension [5 items], physical dimension [7 items], social dimension [4 items], and therapeutic influences [1 item]). A literature search was conducted on the application of GIQLI in GERD patients prior to interventional therapy using reports in PubMed. Data on the mean GIQLI as well as index data for the 5 dimensions as originally validated were extracted from the published patient cohorts. A comparison with the normal healthy control group from the original publication of the GIQLI validation conducted by Eypasch was performed. Data are presented descriptively as GIQLI points as well as a reduction from 100% maximum possible index points (max 144 index points = highest QOL). Results: In total, 77 abstracts from studies using the GIQLI on patients with GERD were identified. After screening for content, 21 publications were considered for further analysis. Ten studies in GERD patients comprised complete calculations of all dimensions and were included in the analysis. Data from 1,682 study patients were evaluated with sample sizes ranging from 33 to 568 patients (median age of 789 females and 858 males: 51.8 years). The median overall GIQLI for the patient group was 91.7 (range 86–102.4), corresponding to 63.68% of the maximum GIQLI. The dimensions with the largest deviation from the respective maximum score were the physical dimension (55% of maximum) followed by the emotional dimension (60% of maximum). In summary, the GIQLI level in GERD cohorts was reduced to 55–75% of the maximum possible index. Conclusions: Severe GERD causes substantial reductions in the patient’s QOL. The level of GIQLI can carry between different studied GERD cohorts from different departments and countries. GIQLI can be used as an established tool to assess the patient’s condition in various dimensions
Quality of life in benign colorectal disease—a review of the assessment with the Gastrointestinal Quality of Life Index (GIQLI)
Background and purpose The Gastrointestinal Quality of Life Index (GIQLI) is an instrument for the assessment of qual‑
ity of life (QOL) in diseases of the upper and lower GI tract, which is validated in several languages around the world. The
purpose of this literature review is the assessment of the GIQLI in patients with benign colorectal diseases. Reports on
GIQLI data are collected from several institutions, countries, and different cultures which allows for comparisons, which
are lacking in literature.
Methods The GIQL Index uses 36 items around 5 dimensions (gastrointestinal symptoms (19 items), emotional dimension
(5 items), physical dimension (7 items), social dimension (4 items), and therapeutic influences (1 item). The literature search
was performed on the GIQLI and colorectal disease, using reports in PubMed. Data are presented descriptively as GIQL Index
points as well as a reduction from 100% maximum possible index points (max 144 index points=highest quality of life).
Results The GIQLI was found in 122 reports concerning benign colorectal diseases, of which 27 were finally selected for
detailed analysis. From these 27 studies, information on 5664 patients (4046 female versus 1178 male) was recorded and
summarized. The median age was 52 years (range 29–74.7). The median GIQLI of all studies concerning benign colorectal
disease was 88 index points (range 56.2–113). Benign colorectal disease causes a severe reduction in QOL for patients down
to 61% of the maximum.
Conclusions Benign colorectal diseases cause substantial reductions in the patient’s QOL, well documented by GIQLI, which
allows a comparison QOL with other published cohorts
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