191 research outputs found
Automated generic integration of flight logbook data into aircraft maintenance systems
The automated transfer of flight logbook information from aircrafts into aircraft maintenance systems leads to reduced ground and maintenance time and is thus desirable from an economical point of view. Until recently, flight logbooks have not been managed electronically in aircrafts or at least the data transfer from aircraft to ground maintenance system has been executed manually. Latest aircraft types such as the Airbus A380 or the Boeing 787 do support an electronic logbook and thus make an automated transfer possible. A generic flight logbook transfer system must deal with different data formats on the input side -- due to different aircraft makes and models -- as well as different, distributed aircraft maintenance systems for different airlines as aircraft operators. This article contributes the concept and top level distributed system architecture of such a generic system for automated flight log data transfer. It has been developed within a joint industry and applied research project. The architecture has already been successfully evaluated in a prototypical implementation
Exploring the Impact of Complexity under Increasing Returns
The development of path-dependent processes basically refers to positive
feedback in terms of increasing returns as the main driving forces of such
processes. Furthermore, path dependence can be affected by context factors,
such as different degrees of complexity. Up to now, it has been unclear
whether and how different settings of complexity impact path-dependent
processes and the probability of lock-in. In this paper we investigate the
relationship between environmental complexity and path dependence by means of
an experimental study. By focusing on the mode of information load and
decision quality in chronological sequences, the study explores the impact of
complexity on decision-making processes. The results contribute to both the
development of path-dependence theory and a better understanding of decision-
making behavior under conditions of positive feedback. Since previous path
research has mostly applied qualitative case-study research and (to a minor
part) simulations, this paper makes a further contribution by establishing an
experimental approach for research on path dependence
Industrial Segment Anything -- a Case Study in Aircraft Manufacturing, Intralogistics, Maintenance, Repair, and Overhaul
Deploying deep learning-based applications in specialized domains like the
aircraft production industry typically suffers from the training data
availability problem. Only a few datasets represent non-everyday objects,
situations, and tasks. Recent advantages in research around Vision Foundation
Models (VFM) opened a new area of tasks and models with high generalization
capabilities in non-semantic and semantic predictions. As recently demonstrated
by the Segment Anything Project, exploiting VFM's zero-shot capabilities is a
promising direction in tackling the boundaries spanned by data, context, and
sensor variety. Although, investigating its application within specific domains
is subject to ongoing research. This paper contributes here by surveying
applications of the SAM in aircraft production-specific use cases. We include
manufacturing, intralogistics, as well as maintenance, repair, and overhaul
processes, also representing a variety of other neighboring industrial domains.
Besides presenting the various use cases, we further discuss the injection of
domain knowledge
A review of revenue management : recent generalizations and advances in industry applications
Originating from passenger air transport, revenue management has evolved into a general and indispensable methodological framework over the last decades, comprising techniques to manage demand actively and to further improve companies’ profits in many different industries. This article is the second and final part of a paper series surveying the scientific developments and achievements in revenue management over the past 15 years. The first part focused on the general methodological advances regarding choice-based theory and methods of availability control over time. In this second part, we discuss some of the most important generalizations of the standard revenue management setting: product innovations (opaque products and flexible products), upgrading, overbooking, personalization, and risk-aversion. Furthermore, to demonstrate the broad use of revenue management, we survey important industry applications beyond passenger air transportation that have received scientific attention over the years, covering air cargo, hotel, car rental, attended home delivery, and manufacturing. We work out the specific revenue management-related challenges of each industry and portray the key contributions from the literature. We conclude the paper with some directions for future research
Management of pineal region tumors in a pediatric case series
Pineal region tumors commonly present with non-communicating hydrocephalus. These heterogeneous histological entities require different therapeutic regimens. We evaluated our surgical experience concerning procurance of a histological diagnosis, management of hydrocephalus, and choice of antitumoral treatment. We analyzed the efficacy of neuroendoscopic biopsy and endoscopic third ventriculocisternostomy (ETV) in patients with pineal region tumors between 2006 and 2019 in a single-center retrospective cross-sectional study with regard to diagnostic yield, hydrocephalus treatment, as well as impact on further antitumoral management. Out of 28 identified patients, 23 patients presented with untreated hydrocephalus and 25 without histological diagnosis. One patient underwent open biopsy, and 24 received a neuroendoscopic biopsy with concomitant hydrocephalus treatment if necessary. Eighteen primary ETVs, 2 secondary ETVs, and 2 ventriculoperitoneal shunts (VPSs) were performed. Endoscopic biopsy had a diagnostic yield of 95.8% (23/24) and complication rates of 12.5% (transient) and 4.2% (permanent), respectively. ETV for hydrocephalus management was successful in 89.5% (17/19) with a median follow-up of more than 3 years. Following histological diagnosis, 8 patients (28.6%) underwent primary resection of their tumor. Another 9 patients underwent later-stage resection after either adjuvant treatment (n = 5) or for progressive disease during observation (n = 4). Eventually, 20 patients received adjuvant treatment and 7 were observed after primary management. One patient was lost to follow-up. Heterogeneity of pineal region tumor requires histological confirmation. Primary biopsy of pineal lesions should precede surgical resection since less than a third of patients needed primary surgical resection according to the German pediatric brain tumor protocols. Interdisciplinary decision making upfront any treatment is warranted in order to adequately guide treatment
Transition From Preliminary to Detailed Design of a Highly Elastic Solar Electric Aircraft
This work presents the evolution of the aeroelastic modeling of a solar electric aircraft. The dimensions (wing span of ≈27.0 m) and the extreme light-weight construction (wing loading ≈4.0 kg/m²) results in a highly flexible aircraft, making aeroelastic analyses mandatory in all stages of the aircraft design. Comparing the preliminary with the detailed design phase, the aeroelastic models are significantly improved in their level of detail. Still, the models show similar structural dynamic characteristics and a comparable loading, e.g. in terms of wing bending and torsional moments and , where the highest loads are caused by similar load cases. For the sizing, the analytic approach from the preliminary design is backed-up with numerical analyses using a detailed FE model. A comprehensive flutter analysis confirms the findings obtained from a flutter check during the preliminary design. Finally, first structural tests are prepared to validate the models
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