1,063 research outputs found
A Hybrid Analytical-Numerical Model Based on the Method of Fundamental Solutions for the Analysis of Sound Scattering by Buried Shell Structures
Several numerical and analytical models have been used to study underwater acoustics problems. The most accurate and realistic models are usually based on the solution of the wave equation using a variety of methods. Here, a hybrid numerical-analytical model is proposed to address the problem of underwater sound scattering by an elastic shell structure, which is assumed to be circular and that is buried in a fluid seabed bellow a water waveguide. The interior of the shell is filled with a fluid that may have different properties from the host medium. The analysis is performed by coupling analytical solutions developed both for sound propagation in the waveguide and in the vicinity of the circular hollow pipeline. The coupling between solutions is performed using the method of fundamental solutions. This strategy allows a compact description of the propagation medium while being very accurate and highly efficient from the computational point of view
Emphasizing the losses or the gains: comparing situational and individual moderators of framed messages to promote fruit and vegetable intake
Health messages are a commonly used way to promote changes in dietary habits but their efficacy could be enhanced by strategies such as the way in which the presented arguments are framed. This study aimed to test the effectiveness of framed messages (gain vs. loss) on behavioural intention and fruit and vegetable (FV) intake, comparing predictions based on prominent theoretical perspectives on message framing (function of the health behaviour and recipients' motivational orientation) and by further exploring the role of baseline intentions as a potential moderator of the framing effects. Undergraduate students (N = 180) completed the three assessment points in time. At baseline, individual moderators (motivational orientation and intentions) and fruit and vegetable intake were assessed. One week later, participants were randomly assigned to the loss or gain-framed message and indicated their intentions for FV intake the following week. A week later, FV intake over the previous week was assessed. The gain-frame was not conducive, per se, to higher intentions or behaviour. Having intention as the outcome, only baseline intentions moderated the effects of message frame. When considering FV intake as the outcome, both motivational orientation and baseline intentions moderated the effects of message frame, with the loss-frame promoting higher FV intake among individuals who were prevention-oriented and had higher baseline intentions. Findings suggest that the success of framed messages for FV intake depends upon the recipient's characteristics, such as motivational orientation, baseline intentions, and cultural background, with implications for health communication interventions.info:eu-repo/semantics/acceptedVersio
When is congruency helpful? Interactive effects of frame, motivational orientation, and perceived message quality on fruit and vegetable consumption
Health messages framed to be congruent with people’s motivational orientation have been shown to be generally effective in promoting health behavior change, but some inconsistencies have been found. This study tested whether the perceived quality of a health message moderated the congruency effect in the domain of fruit and vegetable (FV) consumption. Undergraduate participants (N = 109) read a health message promoting FV intake in which the frame (gain vs. loss) was either congruent or incongruent with their approach/avoidance motivational orientation. Perceived message quality and intention to increase FV intake were assessed after message exposure, and self-reported FV intake was assessed one week later. A significant interaction between congruency and perceived message quality was found on both intention and FV intake. When messages were congruent, higher intentions and FV intake were observed when perceived message quality was high, but the reverse pattern was observed when perceived message quality was low. The findings support the potential utility of using congruently-framed messages to promote fruit and vegetable consumption, while also underscoring the necessity of using high-quality messages in order for congruency to influence health-related behaviors
Health messages to promote fruit and vegetable consumption at different stages: a match-mismatch design
Objective: To examine the effectiveness of matching health messages promoting fruit and vegetable intake to the Health Action Process Approach stages of change.Design: In a randomised controlled trial, 205 undergraduate students (non-intenders n=123; intenders n=82) were exposed to one of three health messages, targeted at non-intenders, intenders and controls.Main outcome measures: Three longitudinal assessments of stage, fruit and vegetable intake, and social-cognitive determinants were obtained.Results: Stage-specific effects of the interventions were confirmed. For self-efficacy, a stage by health message crossover interaction emerged, with both non-intenders and intenders in the matched conditions scoring higher in self-efficacy. Furthermore, in line with predictions, non-intenders in the matched condition showed higher risk perception, outcome expectancies, intention, and stage progression immediately after message exposure, and lower levels of action planning and coping planning a week later in the mismatched condition, but for these outcomes no differences across conditions were obtained among intenders. Multiple mediation analyses confirmed the facilitating role of self-efficacy and behavioural intention among non-intenders.Conclusions: Stages should be considered when designing health messages, although more interactive interventions for intenders and extended measurement time frames may be required.info:eu-repo/semantics/acceptedVersio
Remote sensing applied to geological mapping and tectonics : a study in the Viseu region, Central Portugal
A novel way to automatically plan cellular networks supported by linear programming and cloud computing
With the increasing number of mobile subscribers worldwide, there is a need for fast and reliable algorithms for planning/optimization of mobile networks, especially because, in order to maintain a network’s quality of service, an operator might need to deploy more equipment. This paper presents a quick and reliable way to automatically plan a set of frequencies in a cellular network, using both cloud technologies and linear programming. We evaluate our pattern in a realistic scenario of a Global System for Mobile communications protocol (GSM) network and compare the results to another already implemented commercial tool. Results show that even though network quality was similar, our algorithm was twelve times faster and used four times less memory. It was also able to frequency plan seventy cells simultaneously in less than three minutes. This mechanism was successfully integrated in the professional tool Metric, and is currently being used for cellular planning. Its extension for application to 3/4/5G networks is under study.info:eu-repo/semantics/publishedVersio
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