Search results for "Reliability"
showing 10 items of 1563 documents
Optimal design of tuned liquid column dampers for seismic response control of base-isolated structures
2017
In this paper, the use of a tuned liquid column damper (TLCD) as a cost-effective means to control the seismic response of a base-isolated structure is studied. A straightforward direct approach for the optimal design of such a device is proposed, considering a white noise model of the base excitation. On this base, a direct optimization procedure of the TLCD design parameters is performed and optimal design charts are presented as a ready-to-use practical design tool. Comparison with the optimal parameters obtained considering a classical iterative statistical linearization technique proves the reliability of the proposed approach. The performance of the base-isolated TLCD-controlled struc…
Energy Efficient Sink Placement in Wireless Sensor Networks by Brain Storm Optimization Algorithm
2018
Wireless sensor networks represent one of the most promising technologies whose use has significantly increased in the past years. They are used in various applications such as health care monitoring, surveillance and monitoring in agriculture, industrial monitoring, habitat and underwater monitoring, etc. Deployment of the wireless sensor networks introduces number of hard optimization problems. Placement of the elements such as sensors, gateways, sinks and base stations, depend on different conditions and constraints such as signal propagation, distance, energy preservation, reliability. In this paper, we propose a method based on brain storm optimization algorithm for placing multiple si…
Measuring organisational learning capability among the workforce
2007
PurposeThe present study sets out to propose and validate a measurement scale that aims to capture the organisational capability to learn, based on a comprehensive analysis of the facilitating factors for learning. The organisational learning capability scale consists of 14 items grouped into five dimensions: experimentation, risk taking, interaction with the external environment, dialogue, and participative decision making.Design/methodology/approachData were collected from eight Spanish ceramic tile manufacturers. The survey was addressed to shop floor workers. A total of 157 valid questionnaires were obtained, representing a response rate of 61 per cent. Using confirmatory factor analysi…
Utrecht Work Engagement Scale in Dominican Teachers: Dimensionality, Reliability, and Validity
2018
Work engagement is described by dedication, vigor, and absorption. The most widely used measure of engagement is the Utrecht Work Engagement Scale (UWES), intended to measure engagement for any occupational group. This research aims to study psychometric properties of the UWES for its use in the Dominican Republic and other Caribbean Spanish-speaking countries. The Composite Reliability Index (CRI) as well as alphas were calculated, indicating good internal consistency. Confirmatory factor analyses were carried out to test its dimensionality. Both tested models showed extremely good fit to the data, which called for model comparison. The three-factor solution was retained as the one showing…
Probabilistic Fuzzy Approach to Evaluation of Logistics Service Effectiveness
2014
Received: 9 September 2014 Abstract Accepted: 11 October 2014 Logistics service providers offer a whole or partial logistics business service over a certain time period. Between such companies, the effectiveness of specific logistics services can vary. Logistics service providers seek the effective performance of logistics service. The purpose of this paper is to present a new approach for the evaluation of logistics service effectiveness, along with a specific computer system implementing the proposed approach – a sophisticated inference system, an extension of the Mamdani probabilistic fuzzy system. The paper presents specific knowledge concerning the relationships between effectiveness i…
Testing invariance between web and paper students satisfaction surveys. A case study
2017
[EN] Purpose: This paper studied the measurement invariance (MI) across web-based and paper-based surveys to evidence if both techniques of data collection can be regarded as equivalent. Design/methodology: We develop a multigroup confirmatory factor analysis (MGCFA) with Maximum Likelihood Estimation to asses measurement invariance of the Job Diagnostic Survey (JDS) adapted to teaching, with data collected from paper and web surveys. Sample from paper surveys was constituted by 294 student of a Spanish public university in the academic years 2007-08, 2008-09 and 2009-10. Internet surveys were administered through an open source survey application called Lime Survey. We received 241 complet…
The Italian Version of the Career Factors Inventory
2015
This study attempted to examine the validity of the Italian version of the Career Factors Inventory (CFI), a psychometric tool widely used in the assessment of cognitive and personal–emotional dimensions of career indecision, among a sample of 2,060 Italian students attending high school and university. Recurring to both exploratory and confirmatory factor analyses, the original four-factor structure was confirmed and returned, in line with the literature, satisfactory reliability indices; moreover, CFI subscales showed intercorrelations consistent with previous studies, albeit lower in some cases. Subsequently, convergent validity between the four CFI subscales and other scales via zero-o…
L’attenzione per il benessere organizzativo nella Pubblica Amministrazione italiana. Analisi critica del questionario CIVIT/ANAC
2018
L'articolo propone una riflessione sugli studi inerenti al benessere organizzativo nel nostro Paese, e un'analisi secondaria sul questionario per la valutazione del Benessere organizzativo nella pubblica amministrazione italiana CIVIT/ANAC realizzata tra il personale tecnico amministrativo di alcuni atenei italiani, con tre obiettivi: confrontare le dimensioni del benessere incluse nel questionario con i fattori considerati nei più noti modelli che in letteratura hanno definito il costrutto del benessere al lavoro; controllare attendibilità e validità dello strumento; identificare la struttura semantica soggiacente alle risposte, prescindendo dall'impostazione precostituita del questionario.
Influence of clinical and psychological variables upon the oral health-related quality of life in patients with temporomandibular disorders
2017
Background To analyze the association between the OHIP-14 and the different subtypes making up the clinical and psychological axis obtained using the RDC/TMD. Material and Methods 407 patients treated at the TMD unit of the Andalusian Healthcare Service were administered the Spanish version of the Research Diagnostic Criteria for Temporomandibular Disorders questionnaire (RDC/TMD), together with the Oral Health Impact Profile questionnaire (OHIP-14). The degree of association between the patients’ score in the OHIP-14 and the clinical and biopsychosocial variables was analyzed through bivariate and multivariate analyses, specifically through linear regression. Results 89.4% of the treated p…
Dental measurements and Bolton index reliability and accuracy obtained from 2D digital, 3D segmented CBCT, and 3d intraoral laser scanner
2017
Background To compare the reliability and accuracy of direct and indirect dental measurements derived from two types of 3D virtual models: generated by intraoral laser scanning (ILS) and segmented cone beam computed tomography (CBCT), comparing these with a 2D digital model. Material and methods One hundred patients were selected. All patients' records included initial plaster models, an intraoral scan and a CBCT. Patients´ dental arches were scanned with the iTero® intraoral scanner while the CBCTs were segmented to create three-dimensional models. To obtain 2D digital models, plaster models were scanned using a conventional 2D scanner. When digital models had been obtained using these thr…