Search results for "Measurement"
showing 10 items of 2918 documents
Gravitational Lensing of Supernova Neutrinos
2006
The black hole at the center of the galaxy is a powerful lens for supernova neutrinos. In the very special circumstance of a supernova near the extended line of sight from Earth to the galactic center, lensing could dramatically enhance the neutrino flux at Earth and stretch the neutrino pulse.
Assessing maintainability change over multiple software releases
2008
The focus of the paper is to reveal the relationships between software maintainability and other internal software quality attributes. The source code characteristics of five Java-based open-source software products are analyzed using the software measurement tool SoftCalc. The relationships between maintainability and internal quality attributes are identified based on the Pearson product moment correlation analysis. Our results show negative correlations between maintainability and some well-known internal software quality attributes, as well as the ones between maintainability and complexity metrics. Particularly, according to our results, the Number of Data Variables Declared and the De…
Measurement Invariance of the Multidimensional Scale of Perceived Social Support Among Chinese and South Asian Ethnic Minority Adolescents in Hong Ko…
2020
Seven hundred adolescents (Chinese = 50%; South Asian ethnic minority = 50%) with mean age of 15.3 years (SD = 1.53). Multigroup confirmatory factor analysis was performed to assess measurement invariance of the MSPSS scale across Chinese and South Asian ethnic minority samples. Results show that the original three-factor structure of the MSPSS was supported in both samples. Measurement invariance was supported in terms of configural, metric, and partial scalar invariance. Given partial scalar invariance was achieved, the latent mean differences were compared across samples. Chinese adolescents had higher levels of all three types of social support when compared with their South Asian ethni…
An experimental study for the characterization of fluid dynamics and heat transport within the spacer-filled channels of membrane distillation modules
2018
Abstract The thermo-fluid dynamic behavior of spacer-filled channels for membrane distillation was investigated experimentally. Several different geometry were investigated thanks to customized reference spacers manufactured using a 3D printer. In particular, two sets of experiments were conducted: in the first set, cylindrical filaments were orthogonally arranged and the flow attack angle was made to vary from 0o to 90o; in the second set, the flow attack angle was kept symmetrical and the filament angle was made to vary from 30° to 150°. Each spacer was tested for Reynolds numbers between 200 and 900 in the hot channel, while maintaining a constant temperature difference of 13 °C between …
Encuestas a pie de urna en España. ¿Error muestral o sesgo de no respuesta?
2016
Countless examples of misleading forecasts on behalf of both pre-election and exit polls can be found all over the world. Non-representative samples due to differential nonresponse have been claimed as being the main reason for inaccurate exit-poll projections. In real inference problems, it is seldom possible to compare estimates and true values. Electoral forecasts are an exception. Comparisons between estimates and final outcomes can be carried out once votes have been tallied. In this paper, we examine the raw data collected in seven exit polls conducted in Spain and test the likelihood that the data collected in each sampled voting location can be considered as a random sample of actua…
Performance assessment to investigate the domain specificity of instructional skills among pre‐service and in‐service teachers of mathematics and eco…
2019
Background Key elements of instructional quality include the teacher's ability to immediately react in domain‐specific classroom situations. Such skills – defined as action‐related skills – can only be validly assessed using authentic representations of real‐life teaching practice. However, research has not yet explained how teachers apply domain‐specific knowledge for teaching and to what extent action‐related skills are transferable from one domain to another. Aims Our study aims to examine (1) the relationship between action‐related skills, content knowledge, and pedagogical content knowledge, and (2) the domain specificity of action‐related skills of (prospective) teachers in the two do…
Reintroducing photosynthesis.
2011
This article reports on conceptual difficulties related to photosynthesis and respiratory metabolism of a Plant Physiology course for undergraduate students that could hinder their better learning of metabolic processes. A survey of results obtained in this area during the last 10 academic years was performed, as well as a specific test, aimed to find out prior conceptual schemes in the students. The test included only basic, general questions on plant metabolism, and was passed on the first day of the course. Scores obtained by different groups of students were compared. Survey of students' performance in previous years shows that questions on plant metabolism result in significantly lower…
Multi-site analytical evaluation of a chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the Abbott ARCHITECT analyzer.
2009
Objective This study evaluated a new chemiluminescent magnetic microparticle immunoassay (CMIA) for sirolimus on the ARCHITECT analyzer. Design and methods Patient and laboratory proficiency samples were tested at three European sites and one site in the United States. Results The CMIA total %CV's were all < 8% and the Limit of Quantification (LOQ) was < 1.52 ng/mL across the four sites. It cross-reacts to sirolimus metabolites F4 and F5 and showed no hematocrit interference over a range of 25% to 55%. Patient specimen correlations to three LC/MS/MS methods gave R ≥ 0.91 at three sites and mean biases of 14%, 25% and 39%. CMIA patient specimen correlations to the Abbott IMx gave R ≥ 0.94 at…
Speech Activity Detection under Adverse Noisy Conditions at Low SNRs
2021
Speech originating from the noisy environments degrades the speech quality and intelligibility, thus reducing the human perceived Quality of Experience (QoE). For example, surveillance using drone during natural catastrophe needs an efficient speech recognition device to recognise the speech of the frozen human in presence of drone noise to save their life. Therefore, it often requires to pre-process the noisy speech in order to reduce the noise artifacts and enhance the speech. This paper detects the speech activity using Voice Activity Detection (VAD). The VAD distinguishes speech activity (speech presence) and speech inactivity (silence/noise) by extracting the speech features and compar…
The performance of the cryogenic buffer-gas stopping cell of SHIPTRAP
2018
Direct high-precision mass spectrometry of the heaviest elements with SHIPTRAP, at GSI in Darmstadt, Germany, requires high efficiency to deal with the low production rates of such exotic nuclides. A second-generation gas stopping cell, operating at cryogenic temperatures, was developed and recently integrated into the relocated system to boost the overall efficiency. Offline measurements using 223Ra and 225Ac recoil-ion sources placed inside the gas volume were performed to characterize the gas stopping cell with respect to purity and extraction efficiency. In addition, a first online test using the fusion-evaporation residue 254No was performed, resulting in a combined stopping and extrac…