1,720,959 research outputs found
Model-based analysis of a crossover study on aircraft passenger comfort
No full textThis paper describes a model-based strategy adopted for the analysis of aircraft seat comfort data collected in laboratory experiments. A crossover study was planned to investigate the impact of inter-individual variability and timing on seating comfort perceptions. The data analysis strategy is based on cumulative link mixed models (CLMMs). The results confirm the necessity to control the noise factors in order to obtain reliable information for a diagnostic assessment of comfort
The effect of noise factors in experimental studies on aircraft comfort
No full textThis paper describes a strategy adopted for the analysis of aircraft seat
comfort data collected in laboratory experiments. A crossover study was planned to investigate whether the noise factors related to inter-individual variability and timing impact on seating comfort perceptions. The data analysis strategy is based on cumulative link mixed models (CLMMs). The results confirm the necessity to control the noise factors in order to obtain a diagnostic assessment
An Empirical Study of Aircraft Passenger’s Comfort
No full textCommercial aviation is the most global of businesses with more than 60% growth over the last ten years. Despite the impressive growing demand, airlines are still one of the lowest-scoring industries in the American Customer Satisfaction Index. Since aircraft seat is rated as the most unsatisfying aspect of flying, improving sitting comfort can provide a concrete opportunity for airlines to improve customer's satisfaction and loyalty and thus gain competitive edge in aircraft industry. In the specialized literature, the debate about how define and evaluate seat comfort is still open, but the subjective nature of the comfort experience is universally recognized, thus any comfort analysis cannot disregard subjective methods (‘directly asking people about how comfortable they are’), which can be regarded as the most direct way to detect subjective feelings of comfort and/or discomfort. This paper illustrates an industrial case study aiming at assessing and improving the comfort of aircraft seats designed for regional flights. Subjective evaluations about seating comfort were collected during laboratory experiments involving a group of frequent flyers and a team of experts of aircraft seat design. Data have been analysed adopting the framework of generalized mixture models with uncertainty which focus on the data generating process as mainly composed of two factors: an attraction (positive or negative) towards the evaluated item (i.e. feeling component) and an inherent indecision which surrounds any human choice (i.e. uncertainty component). Following this approach subjective comfort responses have been modelled as a mixture of feeling and uncertainty relating both components to seat design features and passenger anthropometrical characteristics and feelings
A model-based approach for the analysis of aircraft seating comfort
No full textBACKGROUND: Aircraft seating comfort has a significant impact on passenger on-board experience. Its assessment requires the adoption of well-designed strategies for data collection as well as appropriate data analysis methods in order to obtain accurate and reliable results. OBJECTIVES: This paper focuses on the assessment of aircraft seating comfort based on subjective comfort responses collected during laboratory experiments and taking into account seat features and passenger characteristics. METHODS: The subjective comfort evaluations have been analyzed using a model-based approach to investigate the relationship between overall seating comfort and specific seat/user characteristics. RESULTS: The results show that the overall seating comfort perception is significantly influenced by the thickness of the seat pan, the backrest position (upright or reclined), the age of the passenger and the passenger perception of being comfortably supported at the lumbar region. CONCLUSIONS: The adopted model-based approach allows the analysis of subjective seating comfort data taking into account their ordinal nature as well as the dependency between evaluations provided by the same subject
A Staggered Seat is Beneficial for the Flying V Aircraft
No full textStaggered seats might be a solution for a V-shaped aircraft (the Fly-ing V). The cabin longitudinal axis of this airplane has a 26 degrees angle with respect to the direction of flight. When seats are positioned in the direction of flight, they consequently have an angle to the cabin and become staggered. It is unknown whether the comfort of this staggered seat is appreciated. In this study, 117 participants tested the comfort and the privacy experience in this staggered seat compared with a regular aircraft seat. The experiment showed that both comfort and privacy were significantly better in the staggered seats. However, the analysis is based on short-term evaluations, which means that long-term effects still need to be studied and also the effects of groups travel-ling together need to be investigated
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
