Artigos de revistas: "Environmental aspects of aeronautics"

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Coen, Peter, Alexandra Loubeau, Jonathan Rathsam e Gautam H. Shah. "NASA quesst mission—Community response testing plans". Journal of the Acoustical Society of America 152, n.º 4 (outubro de 2022): A85. http://dx.doi.org/10.1121/10.0015628.

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The National Aeronautics and Space Administration (NASA) has made a commitment to deliver data to the International Civil Aviation Organization’s Committee on Aviation Environmental Protection (ICAO CAEP) defining community response to sounds from supersonic aircraft designed such that their sonic boom is replaced with a soft “thump” sound. The dataset will be a correlation of public perceptions of these sounds to the corresponding acoustic levels and will support efforts to develop international standards for permissible noise from supersonic overflight. The NASA Quesst mission is developing the X-59, a unique research aircraft capable of quiet supersonic flight, and will use the aircraft in a series of community overflight tests to measure acoustic levels of its “sonic thump” and related public response. This presentation will provide an overview of the Quesst mission, including X-59 development, acoustic validation, and community testing with a focus on the plans and technical goals for those community response tests. In addition, results of a NASA-sponsored international workshop on strategies and considerations for key aspects of the community test phase of the Quesst mission, including estimating noise exposure levels and conducting surveys to support the dataset development, will be briefed.

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Haq, Ehsan ul, Farwah Waseem e Abdul Baqi. "Appraisal of Temporal Variations in Atmospheric Compositions over South Asia by Addition of Various Pollutant’s in Recent Decade". Vol 3 Issue 1 3, n.º 1 (8 de fevereiro de 2021): 1–15. http://dx.doi.org/10.33411/ijist/2021030101.

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Atmosphere is an envelope of gasses and aerosols around the planet, 99% of the total mass of atmospheric gases resides within 32km from Earth’s surface in vertical column. From primordial era to current scenario composition of earth endured numerous drastic modifications. In last decade atmosphere had undergone a vigorous change by the addition of many pollutants in both natural and anthropogenic aspects. South Asia is a densely populated; masses here are in a transition state, this developing nation in this region considerably done enough damage to the atmosphere of south Asia by inserting multiple pollutants in atmosphere in a number of anthropogenic activities. These pollutants piled up as a serious danger for people around the globe like Methane (CH4), Sulphur Dioxide (SO2), Carbon Monoxide (CO) Nitrogen Dioxide (NO2), Carbon Dioxide (CO2), Formaldehydes (HCHO) and tropospheric Ozone (O3) etc. “Environmental Remote Sensing” has arisen as a great tool of modern era to get fruitful and precise results to monitor these variations in atmospheric pollutants. The NASA’s (National Aeronautics and Space Administration), Geospatial Interactive Online Visualization ANd aNalysis Infrastructure (Giovanni) system provides access to a wide variety of NASA’s remote sensing data, Variety of environmental data types has permitted the use of Giovanni for different applications to define addition and increase in concentration of various pollutants. Spatio temporal variation of pollutants shows their concentration increased in last decade and in last three years the concentration boosted as compared to last seven years.

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Dyantyi, Noluntu, Adrian Parsons, Cordellia Sita e Sivakumar Pasupathi. "PEMFC for aeronautic applications: A review on the durability aspects". Open Engineering 7, n.º 1 (10 de novembro de 2017): 287–302. http://dx.doi.org/10.1515/eng-2017-0035.

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AbstractProton exchange membrane fuel cells (PEMFC) not only offer more efficient electrical energy conversion, relative to on-ground/backup turbines but generate by-products useful in aircraft such as heat for ice prevention, deoxygenated air for fire retardation and drinkable water for use on-board. Consequently, several projects (e.g. DLR-H2 Antares and RAPID2000) have successfully tested PEMFC-powered auxiliary unit (APU) for manned/unmanned aircraft. Despite the progress from flying PEMFC-powered small aircraft with 20 kW power output as high as 1 000 m at 100 km/h to 33 kW at 2 558 m, 176 km/h [1, 2, 3], durability and reliability remain key challenges. This review reports on the inadequate understanding of behaviour of PEMFC under aeronautic conditions and the lack of predictive methods conducive for aircraft that provide real-time information on the State of Health of PEMFCs.Highlights: The main research findings are–To minimize performance loss due to high altitude and inclination by adjusting cathode stoichiometric ratio.–To improve quality of oxygen-depleted air by controlling operating temperature and stoichiometric ratio.–Need to devise real time prediction methods conducive for determining PEMFC SoH in aircraft.

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Pöplau, Julia, Sebastian Stille, Thijs Romans, Tilmann Beck, Lorenz Singheiser e Gerhard Hirt. "The Influence of Process Parameters on the Forming of Riblets during Riblet Rolling". Key Engineering Materials 611-612 (maio de 2014): 715–22. http://dx.doi.org/10.4028/www.scientific.net/kem.611-612.715.

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In aeronautics, economic and environmental aspects become increasingly important. As those are very much influenced by the frictional drag of the airplane, a reduction of skin friction which causes a major portion of total aerodynamic drag is desirable. One possible approach for passive drag reduction is the application of riblets small longitudinal grooves orientated in flow direction. Through an adapted rolling process, riblets can be brought into metal sheets on a large scale. For this process a thin high-strength steel wire is wound around a work roll to structure it with the negative riblet imprint. In a subsequent step the riblet profile is rolled into the sheet material. Different parameters can influence the process and the quality of the resulting riblet structure. Those parameters that depend on the sheets sheet thickness, material strength, and composition of the sheet are discussed in this paper. Form filling is used as an indicator for riblet quality. It is found that decreasing sheet thickness is beneficial for form filling, but a process dependent minimum sheet thickness exists for which this effect will reverse. Material strength is found to have a much smaller influence on form filling. Nevertheless, harder alloys seem to need a slightly smaller thickness reduction, but higher rolling forces and pressures to achieve desired form filling. Using clad instead of bare materials has a positive influence on form filling and riblet structuring. Furthermore, riblet rolling does not reduce the fatigue strength of the clad material.

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Jafari, Mostafa. "Challenges in Climate Change and Environmental Crisis". International Journal of Space Technology Management and Innovation 3, n.º 2 (julho de 2013): 24–46. http://dx.doi.org/10.4018/ijstmi.2013070102.

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Climate change challenges need to be considered in various dimensions. Aviation industry has multiple impacts on human lives such as impacts on the urban and natural environments. Various dimensions of the issue and its importance have been reported by the IPCC, following a request from the ICAO and the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer in 1999. In this paper different related topics have been investigated. Aviation: Development and Improvement, Climate changes as main environmental crisis, causative source of pollutions: Air pollution (GHGs, aerosol, smoke and particulate, dust), water pollution, biodiversity, hazardous materials, and aeronautical noise. Link between aviation impacts and environmental crisis have been discussed. Different perspectives of the aviation challenge briefly are presented: I- Human dimension, II- Urban environment (local, regional, and global), III- Natural environments (terrestrial, aquatic, and atmospheric) and IV- Birds killed by intervention. In concluding remarks two aspects of the issue, A) benefits, and B) impacts have been considered, and in the end some recommendations have been made on Emissions Trading, Environmental Performance, and Technological Developments.

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Corăbieru, Anișoara, Petrică Corăbieru, Ștefan Velicu, Ioana Arina Gherghescu e Mirela Gabriela Sohaciu. "Durability Increase by Polyester Coating of Some Quaternary Copper-Based Alloys Parts". Sustainability 12, n.º 8 (24 de abril de 2020): 3485. http://dx.doi.org/10.3390/su12083485.

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The need to increase the reliability of the metal parts and the assessment of the cost-quality parameters of a matrix require big manufacturers to find new technological solutions focused on the following aspects: thin layer deposits, metallic coatings, use of bimetals, and multilayer materials. The coating of the copper-based quaternary alloys with carbon graphite impregnated polyester aims to improve the performance of the metal parts used in the aeronautics, automotive, and railway industries. The goal is to achieve the following objectives: to reduce the rate of premature failure, to reduce the maintenance and service costs, and to increase the service life (the competitiveness of the manufacturing companies is positively influenced by the latter). This paper studies the operating behavior of some copper-based quaternary alloys coated with carbon graphite-impregnated polyester. The influence of the carbon graphite coating is studied in terms of operating behavior, especially aiming to assess the intensity of the wear and the intensity of the accumulated wear. On the whole, proper wear behavior entails the possibility of obtaining an increase in the service life.

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Santin, M., A. Traverso e A. Massardo. "Technological aspects of gas turbine and fuel cell hybrid systems for aircraft: a review". Aeronautical Journal 112, n.º 1134 (agosto de 2008): 459–67. http://dx.doi.org/10.1017/s0001924000002426.

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The objective of this work is to make an overview of opportunities and issues related to the aeronautical application of solid oxide fuel cell hybrid systems. The great interest on fuel cells comes from their capacity of producing electric energy with high efficiency at low pollutant production. The application of these systems as full-time auxiliary power units is an interesting alternative in a future scenario, which is supposed to include a More Electric Aircraft and more restrictive environmental standards. A review of the technological aspects of this application is presented. The physical models found in literature were investigated and the results were compared and discussed.

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Rodríguez, Rosamaria, A. Yarza, J. López-Díez, C. Cuerno-Rejado e A. Güemes. "Damage Detection on Typical Aeronautical Structures". Key Engineering Materials 293-294 (setembro de 2005): 677–84. http://dx.doi.org/10.4028/www.scientific.net/kem.293-294.677.

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The paper pursues the exploration of the feasibility and reliability of current damage detection technologies, evaluating their detection capabilities, environmental factors effects, false alarms rate, adaptability to complex geometries, etc. The method to be used is based on finite element modal updating. Three aspects, as outlined below, are covered: testing samples will be aluminium sheets (0.6m x 0.4m x 1.6mm) strengthened with riveted L-shaped stiffeners. Data will be presented from the undamaged specimens. Secondly, the testing of the samples with damage simulated at different places by temporary removal of specific rivets, thus affecting the overall structural characteristics of the structure. The models used for damage identification methods will be fine tuned to properly detect the simulated damages. Finally, using this information, the paper resumes the capabilities of the method to detect and locate the simulated damage.

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Denning, R. M., J. E. Allen e F. W. Armstrong. "The broad delta airliner". Aeronautical Journal 107, n.º 1075 (setembro de 2003): 547–58. http://dx.doi.org/10.1017/s0001924000013439.

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Abstract Aeronautics faces new and increased challenges in the 21st century. These include climate change, long-term fuel supply, traffic congestion, and noise pollution. Radical technological steps will be demanded of the industry in order to maintain a sustainable transportation system. In setting out its ideas for a Sonic Cruiser, Boeing has recently acknowledged that there is a need to look beyond the high-aspect-ratio wing with separate fuselage and podded engine configuration, which it pioneered at the start of the Jet era. This paper sets out the case for the broad delta including its advantages as a basis for achieving higher transonic cruising speeds, with very long range and large payloads, while providing progressive and significantly improved environmental impact. The work is based on concept designs drawing on flight and weight data from the Vulcan bomber and the Concorde aircraft – both pioneering designs, by no means at the end of their technical potential. A broad delta is taken to mean an aircraft of aspect ratio in the range 2 to 4. Not only does such a planform have application to many sizes of airliner, cruising at various high subsonic speeds, but also it is inherently well suited to later application of laminar flow. Wing surfaces undisturbed by flaps and slots and unhampered by very thick wing skins, together with favourable engine inlet locations, could be a basis for improved overall aerodynamic efficiency. Airliners designed for operation in the region of Mach 1 are likely to pose more difficult problems for the aerodynamicist. Designs must cater for both cruise and maximum design speeds, which may encompass the Mach 1 condition.

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Katsiropoulos, Christos V., Spiros G. Pantelakis, Marco Barile e Leonardo Lecce. "Development of a Novel Hybrid Thermoplastic Material and Holistic Assessment of Its Application Potential". Aerospace 8, n.º 11 (18 de novembro de 2021): 351. http://dx.doi.org/10.3390/aerospace8110351.

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Τhe development of a novel hybrid thermoplastic prepreg material enabling the fabrication of next-generation recyclable composite aerostructures produced by affordable, automated technologies is presented in the present work. The new hybrid material is produced using automated equipment designed and developed for this reason. A preliminary assessment of the application of the new material is made to obtain material properties related to its processability as well as to its strength. A typical aeronautical flat skin panel has been identified and produced using an autoclave-based process in order to assess the potential of the new material for producing aircraft structural parts. Moreover, a newly developed holistic index is implemented to enable a more holistic comparison of the suitability of the materials used for the panel production. The aspects considered for the material comparison are the quality, the environmental footprint, and the cost. The results of the study pointed out that the hybrid thermoplastic material that has been developed represents a viable manufacturing option from an industrial point of view and that its implementation in structural component manufacturing leads to clear cost and environmental advantages.

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Zha, Guo Qing, e Yong Bo Zhang. "Compressive Strength Prediction of T300/QY8911 Composite Subjected to Moisture and Temperature Environment Condition". Advanced Materials Research 787 (setembro de 2013): 127–30. http://dx.doi.org/10.4028/www.scientific.net/amr.787.127.

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The purpose of this study is to investigate the effect of moisture and temperature on the compressive strength of T300/QY8911 composites that tend to be used as structural parts of aircrafts. In aeronautical applications, the composites are exposed to severe environmental conditions, and it is known that hot and humid environments can degrade some aspects of the material performance especially the compressive strength. In this paper, an experimental study was carried out to determine the damage progressions. Scanning electron microscope (SEM) was also employed for fractographic investigations. It is observed that the failure of specimens tested in hot and wet conditions always occurs as a result of out-of-plane microbuckling that is attributed to the reduction of matrix strength. Fiber microbuckling model, fiber kinking model and combined model were employed for the compressive strength prediction of the unidirectional T300/QY8911 composites subjected to different environment conditions. Results show that the combined model is more suitable for the compressive strength prediction of T300/QY8911 composite systems when suffering severe environment conditions.

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Шинкарук, В. І., e В. І. Ліповський. "ОГЛЯД ОСНОВНИХ ТЕНДЕНЦІЙ ТА ФАКТОРІВ СУЧАСНОГОРОЗВТКУ АЕРОКОСМІЧНОЇ ГАЛУЗІ". System design and analysis of aerospace technique characteristics 28, n.º 1 (19 de outubro de 2021): 65–84. http://dx.doi.org/10.15421/472107.

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This article has an analytical nature of paper, which consists in reviewing scientific publications to study the main trends in the aerospace industry that have formed in the current conditions of the aerospace services market. In the article also is determined the relevance and place of additive technologies among the spectrum of modern trends.As a result of this work, the authors draw attention to the fact that in recent years there has been a globalization of the aerospace services market in the aerospace industry and, as a consequence of this process becomes fundamental because of the influence of the economic and marketing components, the environmental aspect, international agreements and requirements. In such conditions, the main global trends in the development of the aerospace industry, which are defined and presented in this article, were formed. The emergence of new trends leads to the need for their provision and the search of new modern design and manufacture solutions that are proposed in the scientific community, which are also discussed in this article.The main attention is paid to additive technologies, as well as their application together with the possibilities of topological optimization methods. The development and implementation of 3D printing in the manufacturing and design of aeronautics objects are considered. It is shown what place is occupied by additive technologies in aerospace, as the most innovative manufacturing technology. The main problems of using additive technologies are established, and the development and possibilities of topological optimization methods in combination with the use of additive technologies are considered. These technologies are considered as an effective tool for meeting the criteria of modern trends. The authors of this work also note that the use and implementation of these technologies lead to a number of problems and require a certain revolution in the product life cycle, since the changes concern not only production processes but also design approaches. Conclusions are made about the prospects for integrating additive technologies into engineering processes, the prospects for increasing the mass efficiency of products in cases of using additive technologies and the high potential of innovative lattice structures in aerospace, which open up completely new properties of structures.

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Pămîntaş, Eugen, Gheorghe Cristian Turc e Felicia Veronica Banciu. "Aluminium High Speed Drilling - Some Technological Aspects". Solid State Phenomena 216 (agosto de 2014): 294–97. http://dx.doi.org/10.4028/www.scientific.net/ssp.216.294.

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so-called llightweights materials (aluminum, magnesium, titanium) and their alloys due to multiple applications in various leading industries (aeronautics, automotive, electrical) always stayed in researchers attention both in order to improve their mechanical characteristics and to optimize technologies for cutting processing them. This paper is part of these concerns by trying to find answers to some questions about high-speed drilling of electrolytic aluminum parts and has as targets of the investigation the following: the material machinability, the working parameters optimization, the tool used in drilling and the quality obtained after machining.

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Cîrciu, Ionică, e Constantin Rotaru. "Theoretical and practical aspects of the Coandă effect applied in aeronautics". MATEC Web of Conferences 290 (2019): 06003. http://dx.doi.org/10.1051/matecconf/201929006003.

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The Coandă Effect, or better said, the deviation of fluid jets to stay attached to a convex surface is a complex gas-dynamic effect, named after the Romanian aviation engineer Henri Coandă and it was for the first time highlighted by him in 1910 during the take-off of one of his first planes, Coandă-1910, which was also the first jet plane to fly. During the short flight, Coandă was able to notice the near-fit alignment of the flue gas jets with the airplane fuselage. Later, both Coandă and other scholars have intensively studied the effect that is named The Coandă Effect, in his honor.

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ISTRATE, Bogdan, e Corneliu MUNTEANU. "Tribological aspects of some biodegradable magnesium alloys". INCAS BULLETIN 12, n.º 1 (1 de março de 2020): 83–89. http://dx.doi.org/10.13111/2066-8201.2020.12.1.8.

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In recent years, biodegradable alloys have made their presence felt in a wide variety of fields, such as aeronautics, automotive and medical fields. Biodegradable alloys are considered to be the 3rd generation of biocompatible alloys, replacing classic alloys such as stainless steels and Co-Cr alloys. The paper aims to study the structural aspect and identify some mechanical characteristics of magnesium-calcium alloys used as biodegradable materials in the medical field. It has been observed the formation of a eutectic compound at the limit of magnesium grains and the relative constant value of the apparent coefficient of friction with increasing Ca concentration.

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Pierrat, Eleonore, Lea Rupcic, Michael Z. Hauschild e Alexis Laurent. "Global environmental mapping of the aeronautics manufacturing sector". Journal of Cleaner Production 297 (maio de 2021): 126603. http://dx.doi.org/10.1016/j.jclepro.2021.126603.

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Adjeleian, J., M. Allen, J. L. Humar e G. McRostie. "National aviation museum, Ottawa". Canadian Journal of Civil Engineering 13, n.º 6 (1 de dezembro de 1986): 722–32. http://dx.doi.org/10.1139/l86-107.

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This paper describes various aspects of the design and construction of a new building for the National Aviation Museum, currently nearing completion on a site on the Rockliffe Airport, Ottawa. The museum will house the aeronautical collection now displayed in World War II hangars.The new museum building is shaped like an isosceles right-angled triangle with a short side 161 m long and a clear height of 13.2 m from the floor to the underside of the roof framing. A two-storey wing on the west side contains the public entrances and the administrative offices.The soil at the site consists of a deep layer of preconsolidated sensitive clay underlain by dense glacial till containing boulders, then a layer of dense sand with gravel and boulders. The main columns of the building are supported by 55 m deep piles driven to suitable resistance in the dense sand and boulder layer, while the perimeter columns rest on spread footings, supported on the surface clay layer.The roof structure, which is one of the largest of its kind, consists of a space truss with top and bottom chords staggered with respect to each other and laid on a square grid 3.3 m by 3.3 m. The depth of the roof framing is also 3.3 m.The paper presents details of subsurface exploration and the types of foundations used. The structural framing for the roof as well as the steps involved in the analysis and design of the roof are described. Also presented are details of the fabrication methods, weld testing, and erection procedures. Key words: National Aviation Museum (Ottawa), pile foundations, dynamic testing, structural steel, space truss, welded joint, ultrasonic weld inspection.

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Avis, Jillian. "The Social and Psychological Aspects Behind Flight". INvoke 1 (4 de maio de 2012): 1–13. http://dx.doi.org/10.29173/invoke16194.

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There are a variety of psychological, cognitive and social factors that contribute to in-flight interactions between crew members, and in order to achieve optimal communication and safety levels during flight, the concept of Crew Resource Management has become increasingly important. Crew Resource Management refers to effective teamwork that requires both efficient and effective communication of pertinent information between the flight deck, cabin crew members and those not on the aircraft, but responsible for critical flight information and organization. The concept has been adapted from the National Aeronautics and Space Administration workshop in 1979 which identified various factors common amongst aviation accidents, including poor team leadership, failure to adequately delegate tasks and inadequate computer monitoring. Future implications of Crew Resource Management have extended to online training sessions to improve communication, and principles have also expanded into the fields of dentistry and medicine.

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Anghelina, Florina Violeta, Ionica Ionita, Dan Nicolae Ungureanu, Elena Valentina Stoian, Ileana Nicoleta Popescu, Vasile Bratu, Ivona Petre, Carmen Popa e Alexis Negrea. "Structural Aspects Revealed by X-Ray Diffraction for Aluminum Alloys 2024 Type". Key Engineering Materials 750 (agosto de 2017): 20–25. http://dx.doi.org/10.4028/www.scientific.net/kem.750.20.

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This paper presents experimental results revealed on the samples type 2024 aluminum alloy used in aeronautics. Adequate characterization of 2024 aluminum alloys with special destination (aviation) was achieved by combined investigations:(i) wet chemical analysis, (ii) spectrochemical analysis, (iii) X-ray diffraction and (iv) electron microscopy. The main conclusion that emerges from the investigations carried out on aluminum samples revealed that: (a) alloys fits in terms of composition with the standard specification for 2024, in all cases; (b) microstructure vary in fineness of grain, but meets the requirements of aviation rules; the investigated microstructures have been appreciated as adequate of aluminum alloys type "2024".

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Morey-Holton, Emily R., e Ruth K. Globus. "Hindlimb unloading rodent model: technical aspects". Journal of Applied Physiology 92, n.º 4 (1 de abril de 2002): 1367–77. http://dx.doi.org/10.1152/japplphysiol.00969.2001.

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Since its inception at the National Aeronautics and Space Administration (NASA) Ames Research Center in the mid-1970s, many laboratories around the world have used the rat hindlimb unloading model to simulate weightlessness and to study various aspects of musculoskeletal loading. In this model, the hindlimbs of rodents are elevated to produce a 30° head-down tilt, which results in a cephalad fluid shift and avoids weightbearing by the hindquarters. Although several reviews have described scientific results obtained with this model, this is the first review to focus on the technical aspects of hindlimb unloading. This review includes a history of the technique, a brief comparison with spaceflight data, technical details, extension of the model to mice, and other important technical considerations (e.g., housing, room temperature, unloading angle, the potential need for multiple control groups, age, body weight, the use of the forelimb tissues as internal controls, and when to remove animals from experiments). This paper is intended as a reference for researchers, reviewers of manuscripts, and institutional animal care and use committees. Over 800 references, related to the hindlimb unloading model, can be accessed via the electronic version of this article.

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Rycroft, M. J. "Concise encyclopedia of aeronautics & space systems",. Journal of Atmospheric and Terrestrial Physics 57, n.º 2 (fevereiro de 1995): 213. http://dx.doi.org/10.1016/0021-9169(95)90003-9.

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Melis, Matthew, Mike Pereira, Duane Revilock e Kelly Carney. "Columbia Accident Investigation and Return-to-Flight Effort". Journal of the IEST 49, n.º 1 (20 de junho de 2006): 1–20. http://dx.doi.org/10.17764/jiet.49.1.8g353u65031l1p72.

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On February 1, 2003, the Space Shuttle Columbia broke apart during reentry, resulting in the loss of seven crewmembers. For the next several months an extensive investigation of the accident involved a nationwide team of experts from the National Aeronautics and Space Administration (NASA), industry, and academia, spanning dozens of technical disciplines.

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Thiel, Cora S., Vladimir Pletser e Bernard Foing. "Human crew-related aspects for astrobiology research". International Journal of Astrobiology 10, n.º 3 (18 de maio de 2011): 255–67. http://dx.doi.org/10.1017/s1473550411000152.

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AbstractSeveral space agencies and exploration stakeholders have a strong interest in obtaining information on technical and human aspects to prepare for future extra-terrestrial planetary exploration. In this context, the EuroGeoMars campaign, organized with support from the International Lunar Exploration Working Group (ILEWG), the European Space Agency (ESA), the National Aeronautics and Space Administration (NASA) Ames Research Center and partner institutes, was conducted by the crews 76 and 77 in February 2009 in The Mars Society's ‘Mars Desert Research Station’ (MDRS) in Utah.The EuroGeoMars encompasses two groups of experiments: (1) a series of field science experiments that can be conducted from an extra-terrestrial planetary surface in geology, biology, astronomy/astrophysics and the necessary technology and networks to support these field investigations; (2) a series of human crew-related investigations on crew time organization in a planetary habitat, on the different functions and interfaces of this habitat, and on man–machine interfaces of science and technical equipment.This paper recalls the objective of the EuroGeoMars project and presents the MDRS and its habitat layout. Social and operational aspects during simulations are described. Technical and operational aspects of biology investigations in the field and in the habitat laboratory are discussed in detail with the focus point set on the polymerase chain reaction (PCR)-based detection of microbial DNA in soil samples.

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IORDACHE, Valentin-Marian, e Casandra Venera PIETREANU. "Considerations on control processes in aeronautical organizations in the context of improving safety and efficiency". INCAS BULLETIN 11, n.º 1 (5 de março de 2019): 207–15. http://dx.doi.org/10.13111/2066-8201.2019.11.1.16.

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In modern aeronautical systems, one of the biggest challenges for the management structures is to maintain the control at all levels. Operational safety and efficiency impose the need to control all the associated risks and hazards; thus, in order to achieve organizational performance, a very important aspect is to establish and develop a strong organization with respect to operations and objectives. Nevertheless, performance cannot be achieved without control; the continuous technological development and the environmental variabilities have a great impact on the organizational management processes. Organizations are very complex and they will continue to expand due to the increasing demands of flight operations. The capacity to adapt, considering the permanent transformations in the society, represents a continuous process that needs to be carefully carried in order to diminish or eliminate the errors that may occur due to organizational factors. Controlling each operational step from the beginning represents the premises for obtaining stability and performance.

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Krzyżak, Aneta, Michał Mazur, Mateusz Gajewski, Kazimierz Drozd, Andrzej Komorek e Paweł Przybyłek. "Sandwich Structured Composites for Aeronautics: Methods of Manufacturing Affecting Some Mechanical Properties". International Journal of Aerospace Engineering 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/7816912.

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Sandwich panels are composites which consist of two thin laminate outer skins and lightweight (e.g., honeycomb) thick core structure. Owing to the core structure, such composites are distinguished by stiffness. Despite the thickness of the core, sandwich composites are light and have a relatively high flexural strength. These composites have a spatial structure, which affects good thermal insulator properties. Sandwich panels are used in aeronautics, road vehicles, ships, and civil engineering. The mechanical properties of these composites are directly dependent on the properties of sandwich components and method of manufacturing. The paper presents some aspects of technology and its influence on mechanical properties of sandwich structure polymer composites. The sandwiches described in the paper were made by three different methods: hand lay-up, press method, and autoclave use. The samples of sandwiches were tested for failure caused by impact load. Sandwiches prepared in the same way were used for structural analysis of adhesive layer between panels and core. The results of research showed that the method of manufacturing, more precisely the pressure while forming sandwich panels, influences some mechanical properties of sandwich structured polymer composites such as flexural strength, impact strength, and compressive strength.

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Gallo, Nicola, Silvio Pappadá, Umberto Raganato e Stefano Corvaglia. "Development of the “High Pressure Repair Dome” system for in-situ high performance repair of aeronautic structures". MATEC Web of Conferences 188 (2018): 04004. http://dx.doi.org/10.1051/matecconf/201818804004.

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As the use of composites for high-performance structures for aerospace applications is constantly increasing, together with the complexity and scale of such structures, an increasingly effort is carried out for the development of advanced techniques for composites structural repair. Mechanical loads and environmental conditions often cause composite damages. If material damage is not extensive, structural repair is the most cost-effective solution. Composite patches can be mechanically fastened, adhesively bonded or co-cured. Bonding or co-curing process provides enhanced stress transfer mechanisms, joint efficiencies and aerodynamic performance. In this paper an innovative and reliable technique to repair damaged composite aeronautical components, named High Pressure Repair Dome (HPRD), is shown. The innovative aspect of this solution is the possibility to bond or co-cure a composite prepreg patch under a pressurized dome, thus using a prepreg compatible with the composite structure. HPRD was developed to allow in-situ repairing on full-scale structures, with the possibility of an accurate control of the parameters of the curing cycle. The advantages and performance of HPRD approach will be discussed and compared with traditional techniques, describing the results achieved and the activity on-course for the full industrialization of this system.

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Sangamesh, Rajole, Naveen Kumar, K. S. Ravishankar e S. M. Kulkarni. "Mechanical Characterization and Finite Element Analysis of Jute-Epoxy Composite". MATEC Web of Conferences 144 (2018): 02014. http://dx.doi.org/10.1051/matecconf/201814402014.

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Natural fiber composite materials are such an appropriate material, that replaces synthetic composite materials for many of practical applications where we need high strength and low density. Natural fiber composites combine the technological, ecological and economical aspects. This leads to discovering its vast applications in the aeronautics, automotive, marine and sporting sectors. This paper deals with the study on mechanical characterization (Tensile, Compression and Flexural) of jute/epoxy (JE) polymer composite. The flexural properties of composites are experimentally tested and are simulated in commercially available FEA software. Flexural tested results are in good agreement with FEA results. Scanning electron microscopy (SEM) analysis of the failed samples reveals the matrix dominated failure.

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Stojce Ilcev, Dimov. "Implementation of innovative aeronautical communication, navigation and surveillance (CNS) systems". International Journal of Engineering & Technology 8, n.º 4 (17 de novembro de 2019): 572. http://dx.doi.org/10.14419/ijet.v8i4.30014.

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This paper introduces implementation of innovative Satellite Communication, Navigation and Surveillance (CNS) systems in function of Global Satellite Augmentation System (GSAS) integrated by the current and new projected Regional Satellite Augmentation System (RSAS) worldwide. The satellite communication and navigation systems are presently in use, however the main aspect of any hypothetical RSAS network is implementation of satellite surveillance system employing previous and new CNS solutions for improved Air Traffic Control (ATC) and Air Traffic Management (ATM) in all phases of flight, approaching to airports and during landing. The CNS network also enhances safety and emergency systems, transport security and control of transportation freight, logistics and the security of the crew and passengers onboard aircraft. The proposals for modern multifunctional space segment, DVB-RCS network, RSAS infrastructure, Satellite Automatic Dependent Surveillance-Broadcast SADS-B system for surveillance and movement guidance and control are also discussed as special solutions in airports environments.

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Ji, Guo Ming, Xiao Guang Cai, Liang Zhang, Hui Lai e Bo Wei Zhao. "Comparison Research of Aircraft Panels Connected by Friction Stir Welding and Riveting". Applied Mechanics and Materials 668-669 (outubro de 2014): 3–7. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.3.

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Currently, friction stir welding has had a wide application in connection of aircraft panels. However, researches are rarely carried on in domestic aeronautics field, which involves the differences between FSW panels and traditional riveted panels in aspects of strength and stabilities under various working conditions such as shear and tension and compression. Picture frame fixture was used in this research for comparison test between two types of aircraft panels, which were connected to stringers by riveting and friction stir welding (FSW). Finite element models were established to simulate the panels in the shear tests which proposed a method to simulate the connection types. It is found that the FSW connection performs better than riveted connection in aspects of limiting load and initial buckling load, which proved that panel connected by FSW is better than riveting in mechanical properties. The test result is proved by FEM simulation, and vise versa.

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Francelino, Josiane de Araújo, Ligia Maria Soto Urbina, André Tosi Furtado e Milton de Freitas Chagas. "How public policies have shaped the technological progress in the Brazilian aeronautics industry: Embraer case". Science and Public Policy 46, n.º 6 (14 de agosto de 2019): 787–804. http://dx.doi.org/10.1093/scipol/scz030.

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Abstract Despite the growing interest in Embraer, the Brazilian world leading aircraft manufacturers, little empirical research exists on the role of Public Procurement for Innovation (PPI), in Brazil, on the shaping of technological capabilities of the aeronautics industry. To capture those impacts, developing a methodological approach is necessary. Thus, the objective of this article is to evaluate the impacts of PPI on Embraer over the last forty years, developing a model for categorizing and analyzing the general technological aspects of those impacts, implemented through Brazilian Defense Acquisition Programs. The results suggest that the Brazilian Aeronautical Policy led to the development of very specific technical capabilities in Embraer, which allowed its evolution in civil aviation.

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Moutaoukkil, Assmaa, Ali Idarrou e Imane Belahyane. "Information retrieval approaches". International journal of electrical and computer engineering systems 13, n.º 10 (21 de dezembro de 2022): 961–70. http://dx.doi.org/10.32985/ijeces.13.10.11.

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The area of information retrieval (IR) has taken on increasing importance in recent years. This field is now of interest to large communities in several application domains (security, medicine, aeronautics, etc.). IR studies find relevant information from the semi-unstructured type of data. As the information resources generated after the search can be extensive in quantity and different in quality, it is essential to rank these results according to the degree of relevance. This paper focuses on text information retrieval (TIR) and emphasizes the importance of each IR approach. This study presents insightful aspects of TIR and provides a comparative study between some proposed approaches and models. Each model offers IR advantages and suffers from several limitations.

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Cojocaru, Radu, Lia Nicoleta Boţilă, Cristian Ciucă, Bogdan Radu, Victor Verbiţchi e Ion Aurel Perianu. "General Aspects Concerning Possibilities of Joining by Friction Stir Welding for some of Couples of Materials Usable in the Automotive Industry". Advanced Materials Research 1153 (maio de 2019): 27–35. http://dx.doi.org/10.4028/www.scientific.net/amr.1153.27.

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In recent years, due to its extraordinary qualities, friction stir welding process FSW has found its utility in more and more industrial applications in fields such as: aerospace, aeronautics, naval, automotive and railway. The paper summarizes several achievements in the FSW joining of couples of similar and dissimilar materials used in the automotive industry. There are presented aspects regarding the welding of ferrous metal materials (DD13), couples of non-ferrous metallic materials (Al Cu range) and steels with aluminum. The behavior of FSW of material couples in terms of analysis of microstructural improvements and mechanical characteristics is analyzed. The preliminary results obtained have shown that the FSW process can be successfully applied to the joining of the approached material couples, but with the use of optimized welding tools and technologies.

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Akdil Sönmez, Ayça, e Ali Talip Akpınar. "The role of physical environmental factors on university students’ academic performance". Journal of Human Sciences 14, n.º 4 (16 de dezembro de 2017): 4241. http://dx.doi.org/10.14687/jhs.v14i4.5025.

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Education and the level of educational development in a country constitute the basis for the social and economic development of that country. The importance of academic performance in a country, especially in higher education, can not be denied. It is therefore important to investigate factors that affect academic achievement in the positive or negative way. This paper aims to determine the factors influencing the academic performance of university students in terms of physical environment, including building design and conditions, campus layout and surrounding neighborhood.This is an exploratory research in which qualitative research design is used. Statistical analyses such as regression, correlation and variance (ANOVA) are applied in order to analyze data. Since the whole survey population is made of the students of Aeronautics and Astronautics Faculty of Kocaeli University, there is no sampling method applied. Survey is performed on voluntary basis.It was expected to reach the results supporting the main hypothesis of the research "physical environmental factors, such as building, campus layout and surrounding neighborhood, affect university students’ academic performance". However, the findings are far apart from supporting the main hypothesis. It is found out that there is no relationship and no effect between academic performance and physical environmental factors.Current study might be one of the pioneer studies regarding the university students’ academic performance in context of aviation in Turkey. Despite of the fact that the students like to hold physical environment responsible for their academic failure, it is proven that there is no relation and no effect in between them. Of course, these results are weak in generality since the research is limited to only the Faculty of Aeronautics and Astronautics of Kocaeli University. Research needs to be replicated in different faculties and departments of different universities in order to ensure generalizability.

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Di Lorenzo, Giuseppe, Emma Frosina, Luigi De Petrillo, Davide Lauria, Adolfo Senatore, Francesco Curreri, Guido Saccone, Marcello Kivel Mazuy e Ciro Pascarella. "Design and Development of Hybrid-Electric Propulsion Model for Aeronautics". MATEC Web of Conferences 304 (2019): 03012. http://dx.doi.org/10.1051/matecconf/201930403012.

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Nowadays, worldwide environmental issue, associated to reduction of pollutant and greenhouse emissions are gaining considerable attention. Aviation sector contribution to the whole CO2 released accounts to around 2%, but it is expected to grow in the next future due to increase of demand. Probably, combustion engine design and fuel efficiency have already reached their optimum technology level and only a breakthrough as hybrid-electric propulsion could be able to satisfy the new international more demanding requirements. However, an improvement of the technology readiness level of hybrid-electric propulsion is strongly necessary and many operational and safety challenges should be addressed. In the work here reported, a hybrid-electric model was designed and developed for general aviation aircrafts, by means of the Mathworks® Matlab – Simulink 1D/0D simulation environment. Both thermal and electric energy storage units, transmission systems and power management devices were considered and the overall performances were evaluated during cruise phase and a conventional training mission, characterized by several run(lap) “touch-and-go”. Furthermore, an innovative mathematical methodology was implemented for battery pack discharge profile interpolation. Finally, reliability and accuracy of the new proposed model were evaluated through comparison with the commercial code Simcenter AMESim® software and an average bias only equal to 5% was achieved.

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Savignac, Laurence, Andrew S. Danis, Mathieu Charbonneau e Steen B. Schougaard. "Valorization of carbon fiber waste from the aeronautics sector: an application in Li-ion batteries". Green Chemistry 23, n.º 6 (2021): 2464–70. http://dx.doi.org/10.1039/d0gc03954c.

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Mohr, George C. "Aeronautics in the Year 2000 and Beyond: A Challenge for the Human Operator". Journal of Occupational and Environmental Medicine 32, n.º 4 (abril de 1990): 384. http://dx.doi.org/10.1097/00043764-199004000-00114.

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Nagy, Gábor. "Environmental aspects in accounting". Acta Agraria Debreceniensis, n.º 52 (20 de março de 2013): 127–31. http://dx.doi.org/10.34101/actaagrar/52/2111.

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By the strengthening of the economic competition became it apparent a company can’t be valued separate, it should be examined as a complex system. In the assessment of corporate performance is increasingly emphasized the environmental performance. The relevant information of stakeholder about the environmental performance is todays an expection, For this, a management control system is needed, which provide relevant information to managers, hence facilitating the informed decision. This study highlighted, accounting systems are able to meet this demand sufficiently, the accounting means not only the usual bookkeeping, it can be interpreted as a management-controll system, which can help in the valuation of the environmental performance.

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Bogdanov, Olga, Nataša Bojković e Marijana Petrović. "Vehicle platooning: Environmental aspects". Tehnika 75, n.º 4 (2020): 355–63. http://dx.doi.org/10.5937/tehnika2003355b.

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Environmental protection is actively becoming one of the main issues of the Sustainable Development Agenda, and is therefore in the focus of various scientific papers and publications. In the context of vehicle platooning, the environment represents an important area, considering that some of the main goals of this transport technology are to reduce fuel consumption and the reduction of harmful gas emissions. Both goals are achievable when optimizing the speed of vehicles in the convoy, but they also depend on the number of vehicles in the convoy, the type of road they travel on, the weight/mass they carry, as well as the weather conditions. This paper will provide insights into platooning simulations and researches conducted in real conditions, which will focus on the impact of this transportation technology on the environment.

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Snelling, R. "Environmental aspects of ISDN". IEEE Communications Magazine 25, n.º 12 (dezembro de 1987): 14–16. http://dx.doi.org/10.1109/mcom.1987.1093507.

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Decaillon, Joël. "Corporate responsibility: environmental aspects". Transfer: European Review of Labour and Research 10, n.º 3 (agosto de 2004): 476–79. http://dx.doi.org/10.1177/102425890401000313.

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Wonham, Dr Jon. "Ocean Cities : Environmental aspects". La Houille Blanche, n.º 8 (dezembro de 1995): 60–62. http://dx.doi.org/10.1051/lhb/1995081.

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D., Lastkov, e Dubovaya A. "HEALTH CONDITION: ENVIRONMENTAL ASPECTS". Health, physical culture and sports 17, n.º 1 (2020): 26–32. http://dx.doi.org/10.14258/zosh(2020)1.2.

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LAWRENCE, ROGER. "ASPECTS OF ENVIRONMENTAL CHANGE". New Zealand Geographer 49, n.º 1 (abril de 1993): 52. http://dx.doi.org/10.1111/j.1745-7939.1993.tb02031.x.

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Osipov, V. I. "Sustainable Development: Environmental Aspects". Herald of the Russian Academy of Sciences 89, n.º 4 (julho de 2019): 396–404. http://dx.doi.org/10.1134/s1019331619040087.

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v. Mühlendahl, K. E., M. Otto e J. Spranger. "Environmental aspects in pediatrics". European Journal of Pediatrics 154, n.º 5 (maio de 1995): 337–38. http://dx.doi.org/10.1007/bf02072097.

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Arenholt-Bindslev, D. "Dental Amalgam— Environmental Aspects". Advances in Dental Research 6, n.º 1 (setembro de 1992): 125–30. http://dx.doi.org/10.1177/08959374920060010501.

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Increasing knowledge about the risk of toxic effects caused by anthropogenic mercury accumulation in ecosystems has resulted in a growing pressure for reduction of the discharge of mercury waste. Consequently, the mercury waste problems of dental clinics have been given increased attention, and restrictions on handling and discharge of contaminated waste have been established in several countries. Major amalgam particles from trituration surplus of those produced during the carving and burnishing of new amalgam restorations are generally collected in coarse filters and sold for refinement. Minor amalgam particles released by production of new fillings or by removal of old restorations partly sediment in tubes and drains. The remaining particles are carried with the waste water stream to the local purifying plant. In Scandinavia, the industrial discharge of mercury-contaminated waste water has been reduced to a minimum. According to recent investigations, dental clinics appear to be responsible for the major amount of mercury collected in the sludge generated in purifying plants. If threshold values for heavy metal content, including mercury, are exceeded, the sludge is not allowed to be recycled as fertilizer. Installation of an approved amalgam-separating apparatus in dental clinics is now mandatory in several countries-for example, Switzerland, Germany, Sweden, and Denmark. Approval of amalgam separators is based on national testing programs, including clinical or laboratory tests demanding 95-99% separating efficiency.

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CHALMERS, LEX. "ASPECTS OF ENVIRONMENTAL CHANGE." New Zealand Journal of Geography 94, n.º 1 (15 de maio de 2008): 22–23. http://dx.doi.org/10.1111/j.0028-8292.1992.tb00441.x.

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Rawlings, A. V. "Dry Skin: Environmental Aspects". Exogenous Dermatology 3, n.º 2 (2004): 57–71. http://dx.doi.org/10.1159/000086156.

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Prieur, Michel. "Environmental Agreements: Legal Aspects". Review of European Community & International Environmental Law 7, n.º 3 (novembro de 1998): 301–7. http://dx.doi.org/10.1111/1467-9388.00163.

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Maguire, R. James. "Environmental aspects of tributyltin". Applied Organometallic Chemistry 1, n.º 6 (1987): 475–98. http://dx.doi.org/10.1002/aoc.590010602.

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