Search results for " RELIABILITY"
showing 10 items of 557 documents
Response spectrum analysis of frame structures: reliability-based comparison between complete quadratic combination and damping-adjusted combination
2019
In the framework of seismic design of structures, response spectrum analysis (RSA) is the most commonly used approach in practice. The most popular combination rule is the complete quadratic combination (CQC) which is also prescribed by the most of seismic design codes and is based on the assumptions that the seismic acceleration is a white noise process and the peak factor ratios associated to the total and modal responses are unitary. Recently, the damping adjusted combination (DAC) rule has been developed for base-isolated structures to overcome the aforementioned simplified assumptions. Although it has been proved that the simplifications about peak factors lead to noticeable errors in …
Distinguishing the roles of carrier and biofilm in filtering media for the removal of pharmaceutical compounds from wastewater
2017
Abstract Pharmaceutical compounds (PCs) represent a large group of micropollutants in wastewaters (WW) worldwide. Many PCs are resistant to conventional WW treatment. Moreover, for some PCs the removal process is reversible. The aim of this study was to test three newly developed ceramic carriers for biofilm formation and PCs removal. The testing of untreated WW samples by liquid chromatography coupled to Orbitrap mass spectrometry allowed to detect the occurrence of 18 PCs in the range from 26 ng/L to 20,688 ng/L, with the highest concentrations found for caffeine. Besides, among PCs with concentrations above 1,000 ng/L, ibuprofen (19,234 ng/L), naproxen (1,405 ng/L), xylazine (1,366 ng/L)…
From common operational picture to common situational understanding: An analysis based on practitioner perspectives
2021
Abstract The concepts of Situational Awareness (SA) and Common Operational Picture (COP) are closely related and well-acknowledged to be crucial factors for effective emergency management. In multi-agency operations, such as extreme weather events, the involved first responders manage the event with different mandates, objectives, and tools which can make it challenging to build a COP. Effective collaboration requires a common situational understanding, based on knowledge about each other’s responsibilities and tasks, mutual respect and trust, as well as common communication tools for emergency communication and information sharing. This paper argues that the COP serves as a basis for decid…
Empowering leadership, mindful organizing and safety performance in a nuclear power plant: A multilevel structural equation model
2020
Abstract The aim of this paper is to develop and test a model in which empowering leadership is expected to contribute to developing mindful organizing, which in turn should contribute to safety compliance and safety participation. Empowering leadership was measured at Time 1, and the rest of the variables were measured two years later (Time 2). The sample used for the analyses in this study included 49 teams and 200 employees from a company in the nuclear generation industry with three different sites. The multilevel structural equation analysis performed to test the proposed model revealed an acceptable fit, and most of the paths were statistically significant and presented the expected s…
Validity and Reliability of a Single Question for Leisure-Time Physical Activity Assessment in Middle-Aged Women.
2020
Purpose: To investigate the validity and test–retest reliability of a single seven-level scale physical activity assessment question (SR-PA L7) and its three-level categorization (SR-PA C3). Methods: The associations of SR-PA L7 and C3 with accelerometer-measured leisure-time physical activity (ACC-LTPA) and with the results of four different physical performance tests (6-min walk [n = 733], knee extension [n = 695], vertical jump [n = 731], and grip force [n = 780]) were investigated among women aged 47–55 years participating in the Estrogenic Regulation of Muscle Apoptosis study (n = 795). The reliability was studied using Spearman correlations with 4-month test–retest period (n = 152). R…
Assessing learners’ writing skills in a SLA study: Validating the rating process across tasks, scales and languages
2014
There is still relatively little research on how well the CEFR and similar holistic scales work when they are used to rate L2 texts. Using both multifaceted Rasch analyses and qualitative data from rater comments and interviews, the ratings obtained by using a CEFR-based writing scale and the Finnish National Core Curriculum scale for L2 writing were examined to validate the rating process used in the study of the linguistic basis of the CEFR in L2 Finnish and English. More specifically, we explored the quality of the ratings and the rating scales across different tasks and across the two languages. As the task is an integral part of the data-gathering procedure, the relationship of task p…
Diseño y fiabilidad de un cuestionario sobre la comprensión auditiva/audiovisual
2021
Este trabajo forma parte de una investigación mixta multifase que explora el empleo de preguntas de comprensión audiovisual integradas en el vídeo en forma de subtítulos y sincronizadas con los fragmentos pertinentes para el aprendizaje de lenguas extranjeras. El objetivo principal del artículo es comunicar el diseño y la fiabilidad test-retest de un cuestionario sobre la comprensión auditiva/audiovisual para estudiantes adultos de español como lengua extranjera que sería administrado en estudios posteriores. Además, se analizan las respuestas de los informantes para conocer algunas de sus creencias y preferencias. Veinte aprendientes completaron el cuestionario en dos ocasiones con un inte…
Load capacity and deflection of fire-resistant steel beams
1990
The methodology of defining safety of constructions in fire has not yet been sufficiently verified and agreed upon. This paper includes calculation results for steel beams, which prove that the ultimate load-bearing capacity predicted by plastic design theory, which is valid in engineering calculations, is not sufficient for determining the critical temperature. The reason is that this temperature tends to be limited in some cases by large deflections of beams in fire.
Analysis of a Collapsed Long-Span Reinforced Concrete Roof in South Italy: Design Mistakes and Material Degradation
2020
In 2004, during ordinary maintenance work, consisting of waterproofing a building located in the south of Italy, the long-span (14.5 m) in situ RC roof partially collapsed. The building, constructed in 1950, was in service as a cinema until 1967 and then utilized as a school until 1985. Lastly, it was a hotel until 2000. In 2004, when the building was not in service and was undergoing maintenance work, it partially collapsed under dead load. After the collapse, which involved a large portion of the roof, several beams, and two columns, the Italian court nominated an official technical consultant to investigate the direct and related causes of the failure. After the main causes were identifi…
Excessive Deflection in Long-Span Timber Beams of a Historical Building in the South of Italy: Analysis and Retrofitting Design
2020
AbstractIn 2018, under service conditions, excessive deflections were observed in the long-span timber beams of the first floor of the former Sant’Elisabetta Monastery in Palermo (Italy). The build...