1,720,953 research outputs found
Fuselage Design Studies to Improve Boarding Performance of Novel Passenger Aircraft: An Approach from Knowledge-Based Engineering and Agent-Based Modelling
No full textWith the growth of the aviation industry, aircraft designers are pressured for the development of sustainable solutions able to deal with the increase in traffic as well as congested airports. Turnaround time becomes an increasingly important factor contributing to the overall success of an aircraft design. A shorter turnaround time may allow airlines greater utilization of their fleet, particularly those that operate primarily short/medium haul flights. This would allow for a decrease in operational costs and, by accommodating more traffic, an increase in revenues. Furthermore, airlines able to operate with shorter turnaround times are more attractive for airports, allowing them to increase throughput and combat airport congestion. This, in turn, may allow airlines to negotiate better airport fees, decreasing their direct operation costs. With the powerful impact that the uncontrollable fuel price has on airlines' costs, maximizing revenues and minimizing other operational costs is crucial for airline's survival. Researchers and manufacturers are looking into novel aircraft designs for integrated solutions: aircraft capable of providing a more efficient form of flying, while also tackling the aforementioned problems related traffic growth, airport congestion and airline costs. Appropriate tools and methods are necessary to be able to quantify the effects of design choices over the complete aircraft performance; which must also include on ground operations, measured with turnaround time. Furthermore, these tools and methods must be applicable to unconventional designs and suitable to early design phases, such that novel configurations can also be analysed. This paper presents procedures and tools to assess the turnaround performance of an aircraft at a conceptual design level. Literature shows that boarding is always on the critical path of aircraft turnaround; therefore, for simplicity reasons, on ground operational performance is condensed to boarding performance. Based on previous work performed by the Flight Performance research group at TU Delft, an automatic fuselage and cabin model generator is developed. Furthermore, using NetLogo, an agent-based boarding simulation tool is developed to estimate the boarding time associated to a given cabin design. Both tools are validated, then coupled to facilitate and automate fuselage design studies focused on boarding performance. Parametric studies are run to determine the effect of fuselage design choices on boarding performance. Focus is placed on features that are considered strong determinants of boarding performance, such as doors (number, location and width), aisles (number and width) and overhead stowage compartments (capacity and occupancy). Aisle width results show that overtaking is only possible in aisles wider than 65cm and that, due to the non-linear distribution of aisle blockage dimensions, there are cases in which increasing aisle width does not provide any boarding benefits (between 85cm and 90cm for instance). A strong sensitivity of boarding performance to hand luggage stowage compartments capacity and occupancy is observed. Multidisciplinary effects, such as structural weight penalties and aerodynamic drag penalties, induced by the fuselage design choices are assessed qualitatively. With the exception of structural effects of doors (number, size and location), that are estimated using an empirical method developed by Torenbeek. The tools are applied to two use cases: a Prandtl plane configuration from the project PARSIFAL and a flying wing configuration called Flying V. The Prandtl plane is designed with a non-circular fuselage cross section, implements a 70cm-wide twin aisle cabin configuration, with up to three doors used for boarding. This allows it to carry 308 passengers (comparable to a standard twin aisle aircraft such as the A330-200) within a 44m fuselage (comparable to a standard single aisle aircraft such as the B737-800). From the point of view of boarding, it is shown to perform better than both a conventional twin aisle with equal capacity and a conventional single aisle aircraft of equal length. To avoid structural weight penalties caused by the non-circular fuselage, an alternative circular fuselage design is examined. Door features (i.e. 1.6m wide doors that allow two simultaneous entry queues) are used to compensate for the narrower (48cm) twin aisle configuration. Boarding performance is comparable to the original Prandtl plane. Moreover, a circular fuselage allows for larger overhead stowage compartments, which further improves the boarding performance of the circular Prandtl plane. Also the Flying V, thanks to its double twin-aisle configuration, performs 27-30% better than its conventional counterpart (the Airbus A350). The tools developed are shown to be sufficiently flexible and thus enable boarding studies on novel aircraft configurations at a conceptual level, where early evaluation of their performance is necessary to derisk their development process. Further development of the tools is recommended for future research projects, to increase their applicability to unconventional configurations (such as a blended wing-body, or a multi deck fuselage) and to extend to other activities in the turnaround process besides boarding (such as de-boarding). Finally, it is suggested that some of the features of the boarding tool, such as the determination of stowing time, be studied in more detail, because they have a strong effect on boarding time, yet their validation is sub-optimal due to the shortage of empirical data describing the phenomena.PARSIFALAerospace Engineerin
Planification, décision démocratique, décentralisation. Le comprensorio de Turin
No full textPlanung, demokratische Entscheindung, Dezentralisierung. Der Turiner comprensorio.
Bestimmte italienische Regionen wie z. B. Piemont haben die soziale, räumliche und finanzielle Planung ihrer Einrichtungen interkommunalen Organen anvertraut, um die Planung dem Ort anzunähern, an dem sich der Wille der Bürger zuerst bekundet : den Kommunen. Diese Planungs-organe heißen «comprensorii». Die Besonderheit des comprensorio von Turin besteht darin, daß er die 206 Kommunen seines Einzugsbereichs in einem wirtschaftlichen Entwicklungsprojekt zusammenfassen will, in dem eine Gesamtplanung für den Westen der Landeshauptstadt (das Gebiet von Campo Valo), durchgeführt in Zusammenarbeit mit privaten Unternehmern (besonders Fiat) Vorrang hat.In order to bring closer the planning to the place of social expression represented by the borough some Italian regions like the Piemont entrusted the socio-spatial and financial programming of amenities to intermunicipal organisms : the comprensorio lies in its intention of gathering its 206 boroughs in a plan of economic development, marked in particular by interventions in the west of the regional capital (Campo Volo land) and carried on in collaboration with private firms (especially Fiat).Pour rapprocher la planification du lieu d'expression sociale qu'est la commune, certaines régions italiennes, tel le Piémont, ont confié la programmation socio-spatiale et financière des équipements à un organisme intercommunal : le comprensorio. L'originalité du comprensorio de Turin tient à sa volonté de rassembler ses 206 communes dans un projet de développement économique, marqué notamment par un ensemble d'interventions sur l'ouest de la capitale régionale (terrain de Campo Volo) et mené en collaboration avec les entreprises privées, Fiat en particulier.Planificación, decisién democrática, descentralización. El comprensorio de Turin.
Algunas regiones italianas, como el Piamonte, confiaron la programación socio-espacial y financiera de los equipamientos a organismos intercomunales, los comprensorii, para acercar la planificación al lugar de expresión social, la comuna. La originalidad del comprensorio de Turín reside en su voluntad de reunir las 206 comunas que lo componen tras de un proyecto de desarrollo económico marcado, principalmente, por un con junto de intervenciones al oeste de la capital regional (terreno de Campo Volo) y llevadas a cabo en colaboración con las empresas privadas (en particular, Fiat).Barbieri Carlo Alberto, Isgro Filippo, Sevin Annie, Tanter Annick. Planification, décision démocratique, décentralisation. Le comprensorio de Turin. In: Les Annales de la recherche urbaine, N°28, 1985. Pouvoirs locaux. pp. 94-109
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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