2,754 research outputs found
Effective and Efficient Data Access in the Versatile Web Query Language Xcerpt
Access to Web data has become an integral part of many applications
and services. In the past, such data has usually been accessed
through human-tailoredHTMLinterfaces.Nowadays, rich client interfaces
in desktop applications or, increasingly, in browser-based clients ease data
access and allow more complex client processing based on XML or RDF
data retrieved throughWeb service interfaces. Convenient specifications of
the data processing on the client and flexible, expressive service interfaces
for data access become essential in this context.Web query languages such
as XQuery, XSLT, SPARQL, or Xcerpt have been tailored specifically for
such a setting: declarative and efficient access and processing ofWeb data.
Xcerpt stands apart among these languages by its versatility, i.e., its ability
to access not just oneWeb format but many. In this demonstration, two aspects
of Xcerpt are illustrated in detail: The first part of the demonstration
focuses on Xcerpt’s pattern matching constructs and rules to enable effective
and versatile data access. It uses a concrete practical use case from
bibliography management to illustrate these language features. Xcerpt’s
visual companion language visXcerpt is used to provide an intuitive interface
to both data and queries. The second part of the demonstration shows
recent advancements in Xcerpt’s implementation focusing on experimental
evaluation of recent complexity results and optimization techniques, as
well as scalability over a number of usage scenarios and input sizes
The MODUS approach to formal verification
Background: Software reliability is of great importance for the development of embedded systems that are often used in applications that have requirements for safety. Since the life cycle of embedded products is becoming shorter, productivity and quality simultaneously required and closely in the process of providing competitive products Objectives: In relation to this, MODUS (Method and supporting toolset advancing embedded systems quality) project aims to provide small and medium-sized businesses ways to improve their position in the embedded market through a pragmatic and viable solution Methods/Approach: This paper will describe the MODUS project with focus on the technical methodologies that can assist formal verification and formal model checking. Results: Based on automated analysis of the characteristics of the system and by controlling the choice of the existing opensource model verification engines, model verification producing inputs to be fed into these engines. Conclusions: The MODUS approach is aligned with present market needs; the familiarity with tools, the ease of use and compatibility/interoperability remain among the most important criteria when selecting the development environment for a projec
Hybrid intelligent system for a synchronous rectifier converter control and soft switching ensurement
[Abastract]: This research implements an intelligent control strategy in a synchronous rectifier buck converter to assure that the converter operates in soft-switching mode. The converter is analysed and the two different switching modes are presented: Hard-switching and Soft-Switching. Afterwards, an intelligent model is implemented with the aim of identifying and classifying the switching mode of the power converter.
The model implementation is based on classification methods through intelligent algorithms that differentiate between the two modes of operation. Satisfactory results have been obtained with the implemented classification method, achieving high accuracy and allowing the implementation of the model into the control strategy of the converter; assuring that the converter operates in the desired operating mode: Soft-Switching mode
Validation of the group tasks uncertainty model (MITAG) in a German sample
Task uncertainty is a key factor in teamwork research. This study analyzed the psychometric characteristics of the Spanish Model of Group Tasks Uncertainty (MITAG) in two German samples. The participants (501 team members and 104 team leaders from a German research organization) answered the MITAG together with selected items from the German Job Diagnostic Survey (JDS) and the instrument Ambiguity facets of work (Ambiguitätsfacetten der Arbeit, AfA). Confirmatory factor analysis did not reproduce the original 4-factor structure in the German sample, although the 3 newly identified factors unclarity of goals, new situations, and non-routine resemble the original factors. Results showed sound internal consistency and confirmed the convergent and discriminant validity of the new factors. The MITAG offers a concept-based short scale for researchers and practitioners
La millora de l'avaluació formativa i sumativa a través de l'elaboració de curtmetratges. La participació activa de l'alumnat
Cada cop més, la societat demana estudiants universitaris més ben preparats. L'objectiu ha estat promoure que l'alumnat de Psicologia de les Organitzacions (UB)elaborés curtmetratges utilitzant els continguts teòrics sense explicitar-los, prenent un paper actiu en la creació de coneixement. Amb més de 200 alumnes, els resultats han mostrat que els curts milloren el procés d´aprenentatge i com les avaluacions finals han estat superiors en comparació als grups que no han realitzat curtmetratges
Data dimensionality reduction for an optimal switching mode classification applied to a step-down power converter
Funding for open access charge: Universidade da Coruña/CISUG.[Abstract] A dimensional reduction algorithm is applied to an intelligent classification model with the purpose of improving the efficiency and accuracy. The proposed classification model, used to distinguish the operating mode: Hard- and Soft-Switching, is presented and an analysis of the synchronized rectified step-down converter is done. With the aim of improving the accuracy and reducing the computational cost of the model, three different methods for dimensional reduction are applied to the input dataset of the model: self-organizing maps, principal component analysis and correlation matrix. The obtained results show how the number of variable is highly reduced and the performance of the classification model is boosted: the results manifest an improve in the accuracy and efficiency of the classification
Validation of the German group development (GD) questionnaire
Group Development (GD) is an important variable when researching and evaluating what makes teams successful. We analyzed the psychometric properties of the originally Spanish GD questionnaire with German participants. 501 team members and 104 team leaders, 18 to 65 years old, from a German research organization answered an online survey composed of the GD questionnaire and items related to other group processes of democracy, mutual trust, team spirit, and interest in the team's tasks. Results confirmed the unidimensional factor structure of the translated Spanish version for the German GD construct. Internal consistency, convergent and discriminant validity were good. The German GD correlated as expected to other constructs, and it showed concurrent validity with respect to the team members' motivation and interest in team tasks (r = .79, p < .01). We recommend using the GD in German samples to measure team processes that are highly relevant for team effectiveness
A meta-analysis on the structure of pulmonary rehabilitation maintenance programmes on COPD patients' functional capacity.
Pulmonary rehabilitation (PR) improves functional capacity, health-related quality of life (HRQoL) in COPD patients, and maintenance programmes are relevant in preserving those improvements. However, little is known about the structure of maintenance programmes after PR. We performed a systematic review and meta-analysis of experimental and quasi-experimental studies evaluating individuals with COPD admitted to a maintenance PR programme, delivered after an initial PR programme. We reported functional capacity evaluation (6-minute-walking-test), HRQoL, dyspnoea and symptom control. Searches were performed on the 11th April 2021 using MEDLINE, Embase, EBSCO, CINAHL, Web of Science and Cochrane Library. We extracted summary-level data from trial publications and used a random-effects model, predicting that severe heterogeneity was detected. The protocol was registered in PROSPERO (CRD42021247724). Fifteen studies were included in the meta-analysis, with 1151 participants. Maintenance programmes were associated with a pooled mean increase of 27.08 meters in 6mWT (CI: 10.39 to 43.77; I2 = 93%; p 12 month) home-based programmes; and having a potential MD of -4.20 pts in SGRQ (CI: -4.49 to -3.91; I2 = 0%; p = 0.74). Regarding dyspnoea and exacerbations, we found a nonsignificant trend for improvement after maintenance PR programmes. Severe COPD patients showed smaller improvements in programmes up to a year. Overall, the strength of the underlying evidence was moderate. Despite limitations of risk of bias and heterogeneity, our results support that home-based, supervised, long-term maintenance PR programmes may significantly improve functional capacity in COPD patients and HRQoL
- …