Journal articles on the topic 'Airplanes Parts'
To see the other types of publications on this topic, follow the link: Airplanes Parts.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Airplanes Parts.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Kraus, Jakub, and Ladislav Capoušek. "Transformation of Helicopter PinS Procedures for Airplanes." MAD - Magazine of Aviation Development 1, no. 5 (September 15, 2013): 3. http://dx.doi.org/10.14311/mad.2013.05.01.
Full textAbstract:
<span style="line-height: 115%; font-family: 'Times New Roman','serif'; font-size: 9pt; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: Calibri; mso-ansi-language: EN-GB; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-GB">This article deals with the possibility to use existing helicopter Point in Space procedures with minor changes for airplanes. The basis is to find parts of PinS procedures that need to be changed, suggest these changes, and then determine whether the revised procedures could be usable and could bring the benefits for airplane operations</span>.
2
Brown, Alan S. "Very Light and Fast." Mechanical Engineering 129, no. 01 (January 1, 2007): 24–29. http://dx.doi.org/10.1115/1.2007-jan-1.
Full textAbstract:
This article focuses on the developments in materials, production methods, and turbine designs that have spawned a new class of jets. Cessna’s Citation Mustang became the first very light jet to reach commercialization. According to market leaders, the development of computerized cockpits with simplified displays has also been huge. Composites also let engineers combine lots of parts—panels, framing, rivets—into a single part. The fewer parts, the easier and cheaper it is to assemble and the more reliable the finished airplane. Every aerospace company is looking for bolt-on components that simplify assembly and maintenance. Adam Aircraft seeks to simplify production by making large composite parts. The second mechanical advance that makes very light jets possible is the compact, reliable turbofan. While Pratt is well-known for huge turbines that power commercial passenger jets, the company produces several small turbines. Pratt uses blisks and other technologies to simplify production. The result is a new type of jet, one that makes jet airplanes far more affordable.
3
de Andrade Silva, Bruno César, Mauricio Saldanha Motta, and José Eduardo Ferreira de Oliveira. "Development of a Methodology to Determine Thickness Measurement Uncertainties by Ultrasonic Test in Aerospace Parts." Materials Science Forum 758 (June 2013): 89–97. http://dx.doi.org/10.4028/www.scientific.net/msf.758.89.
Full textAbstract:
In the aerospace industry, each year several commercial airplanes stop its service to carry out detailed routine inspections of their structural members and systems, including the power plant. Among several maintenance services to be performed in an airplane during a check, the corrosion prevention and control program is the one of the most important service since it includes methods of inspection and tasks to prevent corrosion in all airplane structural areas, such as fuselage, wings, stabilizers, flight control surfaces etc. During routine inspections, upon discrepancy detection, some actions must be immediately taken in order to correct the problem and avoid the loss of airplane structural strength. The corrosion removal from any aircraft structural member, in general consists in blending out the damage and carry out a visual and ND inspection (e.g. remaining thickness measurement by ultrasonic test). However, all care must be taken during remaining thickness measurement since systematic and random errors can affect in the results, compromising the final quality of measured parts. The main purpose of this paper is to perform an experimental study of remaining thickness measurement in an aircraft outer wing skin after corrosion removal, objecting to determine the uncertainty sources of the usual method. Also, the study intends to determine the expanded uncertainty in order to purpose a new methodology for the metrological treatment of this process, establishing a conformity zone.
4
Бичков, С. А., О. Д. Донець, and В. Г. Читак. "ОСОБЛИВОСТІ СЕРІЙНОГО ВИРОБНИЦТВА РЕГІОНАЛЬНИХ ПАСАЖИРСЬКИХ ЛІТАКІВ АН-148 ТА АН-158." Open Information and Computer Integrated Technologies, no. 84 (July 2, 2019): 125–43. http://dx.doi.org/10.32620/oikit.2019.84.06.
Full textAbstract:
The main results and peculiarities of putting the family of regional passenger airplanes An-148/An-158 into the batch production are presented. Based on the results of audits of the Aviation Register of the Interstate Aviation Committee and the State Aviation Service of Ukraine the complex of works that had been performed allowed to obtain approval for putting of airplanes into the batch production. The production is carried out in accordance with the requirements of «Guidelines21.2Cfor the Certification and Supervision of Aircraft Production», «Guidelines 21.2D of Certification and Control Procedures over the Civil Aircraft Production», Standards ISO9001-2009 and EN9100 of «Quality Management Systems. Requirements». The functioning of the quality system is constantly monitored by internal inspections.To put the AN-148-100/158 airplanes into the batch production: technological preparation of production for about 65 000 parts, units and assemblies has been made; more than 19 300 items of special technological equipment and tools have been designed and manufactured; more than 75 000 sets of design documentation for the processes of manufacturing, assembling, controlling and testing parts, units, assemblies and systems of airplanes have been worked out; new technological processes in the forging and stamping, mechanical assembly production, aggregate and assembly manufacturing have been completed, improved and implemented; advanced metalworking tools have been tested and implemented in the production; works on restoration of efficiency and improvement of technological equipment have been performed; new technological processes of manufacturing parts and units on numerically controlled programmable machines have been completed and implemented; complex manufacturing and new production processes of manufacturing products from composite and nonmetallic materials, forging and stamping products, foundry and thermal production have been completed and implemented; new equipment and production processes of welding have been mastered and implemented; the information infrastructure of the company has been organized and is being developed; an integrated automated production management system (ASC) has been developed. It functions based on the main data scope computation on a central computer capable to connect users to view the data; automated workplaces based on personal computers have been organized; measures on recruitment and training of the personnel have been organized and carried out.
5
Helmich, Martin. "STATIC TESTS OF UNCONVENTIONAL PROPULSION UNITS FOR ULTRALIGHT AIRPLANES." Acta Polytechnica 54, no. 3 (June 27, 2014): 183–90. http://dx.doi.org/10.14311/ap.2014.54.0183.
Full textAbstract:
This paper presents static tests of a new unconventional propulsion unit for small aviation airplanes. Our laboratory stand – a fan drive demonstrator – enables us to compare various design options. We performed experiments to verify the propulsion functionality and a measurement procedure to determine the available thrust of the propulsion unit and its dependence on engine speed. The results used for subsequent optimization include the operating parameters of the propulsion unit, and the temperature and velocity fields in parts of the air duct.
6
Mieloszyk, Jacek, Andrzej Tarnowski, Michal Kowalik, Rafal Perz, and Witold Rzadkowski. "Preliminary design of 3D printed fittings for UAV." Aircraft Engineering and Aerospace Technology 91, no. 5 (May 13, 2019): 756–60. http://dx.doi.org/10.1108/aeat-07-2018-0182.
Full textAbstract:
Purpose Additive manufacturing technology, also commonly called as 3D printing technology, is entering rapidly into the aerospace world and seems to be its future. Many manufacturing processes are replaced by this technology because the ease of use, low costs and new possibilities to make complicated parts. However, there are only few solutions which present manufacturing of structurally critical parts. Design/methodology/approach Complete process of deriving loads, design of fitting geometry, numerical validation, manufacturing and strength testing was presented. The emphasis was made to show specific features of 3D technology in printed fittings for UAV. Findings The research confirms that the technology can be used for the application of fittings manufacturing. Attention needs to be paid, during the design process, to account for specific features of the 3D printing technology, which is described in details. Practical implications Without a doubt, additive manufacturing is useful for manufacturing complicated parts within limited time and with reduction cost. It was also shown that the manufactured parts can be used for highly loaded structures. Originality/value The paper shows how additive manufacturing technology can be used to produce significantly loaded parts of airplanes’ structure. Only few such examples were presented till now.
7
Theiner, Robert, and Jiří Brabec. "Albi II – a new generation development." MATEC Web of Conferences 304 (2019): 01027. http://dx.doi.org/10.1051/matecconf/201930401027.
Full textAbstract:
The UL-39 Albi university's all-composite ultralight aircraft project, powered by a piston engine and ducted fan, continues at the Department of Aerospace Engineering at Faculty of Mechanical Engineering CTU in Prague and its partners ZALL JIHLAVAN airplanes, s.r.o. and LA composite, s.r.o. by developing its new generation. The article is a follow-up to a contribution from 2017, where the entire genesis of the first prototype was described. The introduction summarizes the experience of the prototype operation and analyzes the deficiencies that required a major redesign of the propulsion unit. Aspects leading to the choice of another propulsion unit arrangement and changes in the ducted fan, airframe and systems are described. The fuselage of the airplane has undergone a dominant change. The paper describes not only structural changes leading to the reduction of the width of the fuselage and its wetted area, but also the changes in manufacturing process of composite parts leading to weight reduction. Following the changes in the fuselage design modifications of the wing (mainly high lift devices) and modification of the horizontal tail plane are described. At the end there is a plan of further development described, which should ultimately lead to the commercialization of the project.
8
Manarvi, Irfan, Amer Sattar, and Jawad Ahmed Jadoon. "Finite Element Analysis (FEA) for Prediction of Wrinkling in Aluminum 6061-T6 Sheets." Applied Mechanics and Materials 197 (September 2012): 691–95. http://dx.doi.org/10.4028/www.scientific.net/amm.197.691.
Full textAbstract:
Aluminum is one of the most popular metal in a wide variety of applications in manufacturing of components for airplanes, automobiles, house hold etc. A wide variety of parts are manufactured using aluminum sheet of different alloy composition. Wrinkling of sheet metal is the most undesirable phenomenon in sheet metal forming, drawing, punching and other similar manufacturing processes. Current research is focused on Finite Element Analysis of Aluminum 6061-T6 sheet to simulate onset and growth of wrinkles of various thicknesses using ANSYS. Based on the results a comparison was drawn between the wrinkling behaviors at varying load values.
9
Rivière-Lorphèvre, Edouard, Enrico Filippi, and Pierre Dehombreux. "Numerical Simulation of Machining Operations on Flexible Parts." Key Engineering Materials 554-557 (June 2013): 1984–91. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.1984.
Full textAbstract:
Airspace industry components frequently need high added value part including some featuredifficult to manufacture. One of the best example is the thin walls of parts (airplanes frames orthe turbine blades) that have a very low stiffness. The finishing operations for high height to thicknessratio parts lead to chatter vibrations, unacceptable dimensional errors or poor surface finish. The optimalmachining strategy determination is often based on trial and error and may not be cost effective(acceptable conditions can be far from the optimum). Simulation of the milling process is a powerfulmean to accelerate the search for better cutting parameters. Cutting forces, vibrations, geometricerrors or roughness can be predicted before the production of the first parts. The classical mechanisticapproach is even though limited while machining flexible parts because the dynamic response ofthe workpiece changes with the position of the cutter. The objective of this paper is to demonstratethe adaptation of numerical simulation of milling operation for the machining of thin-walled plates.Three complementary approaches are developed: location-dependent stability lobes, quasi static approachand full dynamic simulation. Location dependent stability lobes extend the classical theoryto take into account the variation of dynamic response along the workpiece. Quasi static approach isintended to deal with form error during chatter-free machining operations. Full dynamic simulation isa more complex approach intended to simulate the behavior of the complete tool/machine/workpiecesystem. The numerical approach is compared to experimental tests performed on thin plate of titaniumalloys.
10
Cadnum, Jennifer, Heba Alhmidi, and Curtis Donskey. "Planes, Trains, and Automobiles: Use of Carbon Dioxide Monitoring to Assess Ventilation During Travel." Pathogens and Immunity 7, no. 1 (February 25, 2022): 31–40. http://dx.doi.org/10.20411/pai.v7i1.495.
Full textAbstract:
Background: Travel poses a risk for transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory viruses. Poorly ventilated indoor settings pose a particularly high risk for transmission. Methods: We used carbon dioxide measurements to assess adequacy of ventilation during 5 trips that included air travel. During selected parts of each trip that involved indoor settings, we monitored carbon dioxide levels every 1 minute and recorded peak levels and the number of people present. Carbon dioxide readings above 800 parts per million (ppm) were considered an indicator of suboptimal ventilation. Results: Carbon dioxide levels remained below 800 ppm during train rides to and from the airport and inside airports except in a crowded boarding area with ~300 people present. Carbon dioxide levels exceeded 800 ppm inside the airplanes, but the air was filtered with high efficiency particulate air filters. Carbon dioxide levels remained below 800 ppm in common areas of a hotel but exceeded 800 ppm in a hotel room with 2 to 3 occupants and in a fitness center with 3 people exercising. In restaurants, carbon dioxide levels increased above 800 ppm during crowded conditions with 24 or more people present and 75% or more seat occupancy. Conclusion: Our results suggest that ventilation may be sufficient to minimize the risk for airborne transmission in many situations during travel. However, ventilation may be suboptimal in some areas or under certain conditions such as in hotel rooms or when restaurants, fitness centers, or airplane boarding areas are crowded. There is a need for larger scale studies to assess the quality of ventilation in a wide range of community settings.
11
Moravec, Jaromír, and Marek Slováček. "Application of Numerical Simulations at Welding Multilayer Welds from the Material X22CrMoV12-2." Advanced Materials Research 1029 (September 2014): 31–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1029.31.
Full textAbstract:
Heat-resisting martensitic steel X22CrMoV12-1 is suitable to be used particularly for steam turbine components (e.g. blades or action wheels of steam turbines) and as parts of airplanes structural devices. The aim of this paper is to show how numerical simulations can help to optimize welding procedure of this very hardly weldable material. On the real multilayer weld will be described how to arrange whole experiment in order to obtain not only relevant input data but also verification data. As a result it will be possible to set up the computational model for this type of steel and consequently to use it for simulation computations of welding and heat treatment of real structure components.
12
Raheja, Dev. "System Safety in Healthcare." Journal of System Safety 53, no. 1 (April 1, 2017): 12–14. http://dx.doi.org/10.56094/jss.v53i1.98.
Full textAbstract:
A new technology, three-dimensional (3D) printing, has the potential to change the medical world. Objects are made by fusing or depositing materials, such as plastic, metal, powders, liquids or living cells, in layers to produce a 3D object. This technology started in manufacturing and was used to create spare parts for airplanes, eliminating the need for constructing manufacturing prototypes and producing new components within hours instead of weeks.
The application of this technology in healthcare is growing. It is now used in the creation of customized prosthetics, implants and anatomical models. Its usage is expanding rapidly in other areas of healthcare, including pharmaceutical research regarding drug dosage forms, delivery and discovery.
13
Denkena, B., B. Bergmann, T. Lepper, B. Rahner, S. Schneider, G. Nonnast, F. Preller, F. Hannesen, and G. Braungardt. "Ein Roboter für die effiziente Zerspanung*/A robot for efficient milling operations - Cutting of carbon fibre reinforced plastics using a new machine kinematic." wt Werkstattstechnik online 109, no. 03 (2019): 194–98. http://dx.doi.org/10.37544/1436-4980-2019-03-92.
Full textAbstract:
Kohlefaserverstärkte Kunststoffe werden verstärkt in der Luft- und Raumfahrt sowie in der Automobilindustrie eingesetzt, um durch Leichtbau die Energieeffizienz zu verbessern. Die spanende Nachbearbeitung dieser Teile ist besonders bei Funktionsflächen zwingend erforderlich und beeinflusst die Stückkosten wesentlich. Mit einer neu entwickelten Werkzeugmaschinenkinematik, einer von Beginn an berücksichtigten Absaugung sowie einem hohen Automatisierungsgrad sollen die Fertigungskosten gesenkt werden. In aerospace and automobile industry, fibre reinforced plastics are commonly used to reduce the energy consumption of vehicles and airplanes by means of lightweight construction. Functional surfaces on parts made of fibre reinforced plastics need to be machined by milling operations, which increases production costs per piece. Thus, a new cost-efficient machine tool has been developed with a built-in extraction and a high degree of automation.
14
Bohning, Gerry, and Marguerite C. Radencich. "Math Action Books: For Young Readers." Arithmetic Teacher 37, no. 1 (September 1989): 12–13. http://dx.doi.org/10.5951/at.37.1.0012.
Full textAbstract:
Primary-grade children delight in using three-dimensional action books. Why not build on this interest to help them to practice their counting and basic mathematics facts? Action books have movable parts and are often called pop-up or pop-out books, lift-the-flap books, or surprise books. Children lift flaps, pull tabs, slide panels, move wheels, or turn pop-up pages to initiate a three-dimensional movement. Mathematics three-dimensional action books offer skill practice in a helpful and exciting format. Children can add apples that slide into baskets, subtract airplanes that disappear behind lift-flap clouds, count pop-up crabs that crawl on the shore, or move hands on a clock to show when it is lunchtime.
15
BEKEY, GEORGE A. "On autonomous robots." Knowledge Engineering Review 13, no. 2 (July 1998): 143–46. http://dx.doi.org/10.1017/s0269888998002033.
Full textAbstract:
Autonomous robots are the intelligent agents par excellence. We frequently define a robot as a machine that senses, thinks and acts, i.e., an agent. They are distinguished from software agents in that robots are embodied agents, situated in the real world. As such, they are subject both to the joys and sorrows of the world. They can be touched and seen and heard (sometimes even smelled!), they have physical dimensions, and they can exert force on other objects. These objects can be like a ball in the RoboCup or Mirosot robot soccer games, they can be parts to be assembled, airplanes to be washed, carpets to be vacuumed, terrain to be traversed or cameras to be aimed. On the other hand, since robots are agents in the world they are also subject to its physical laws, they have mass and inertia, their moving parts encounter friction and hence heat, no two parts are precisely alike, measurements are corrupted by noise, and alas, parts break. Of course, robots also contain computers, and hence they are also subject to the slings and arrows of computer misfortunes, both in hardware and software. Finally, the world into which we place these robots keeps changing, it is non-stationary and unstructured, so that we cannot predict its features accurately in advance.
16
Tabatabaei, Hamed Mofidi, Takahiro Ohashi, and Tadashi Nishihara. "Innovative Method of Embedding Optical Fiber inside Titanium Alloy Utilizing Friction Stir Forming." Key Engineering Materials 934 (November 28, 2022): 67–73. http://dx.doi.org/10.4028/p-683ks0.
Full textAbstract:
The development of FBG (Fiber Bragg Grating) sensors is essential for intelligent parts of airplanes to achieve ultra-lightweight structures and intelligent aviation control. Awaiting solution is embedding technology of optical fiber sensors into the base material of the parts; however, it has been challenging to embed fibers into high melting temperature point alloys like titanium-based materials without having any defects. Present research fulfills the mentioned demands effectively by utilizing Friction Stir Forming (FSF). Precisely, optical fiber has been placed into a guide slit inside the titanium sheet. Then, FSF was applied to the surface of the titanium. As a result, titanium plasticizes and flows into the guide slit. This mechanically interlocks the optical fiber inside the titanium alloy. This solid-state stirring process can bury sensors inside the titanium to protect the sensor from harsh environments. Embedded sensors will detect the strain and temperature of the host titanium in real-time. Moreover, this research can have further considerable effects on the areas like aerospace and artificial intelligence systems that demand real-time condition monitoring systems.
17
Dahlström, Stefan, and Lars Lindkvist. "Variation Simulation of Sheet Metal Assemblies Using the Method of Influence Coefficients With Contact Modeling." Journal of Manufacturing Science and Engineering 129, no. 3 (November 13, 2006): 615–22. http://dx.doi.org/10.1115/1.2714570.
Full textAbstract:
Sheet metal assembly is a common assembly process for several products such as automobiles and airplanes. Since all manufacturing processes are affected by variation, and products need to have a high geometric quality, geometry-related production problems must be analyzed during early design phases. This paper discusses two methods of performing this analysis. One way of performing the simulations relatively fast is to establish linear relationships between part deviation and assembly springback deviation by using the method of influence coefficient (MIC). However, this method does not consider contact between the parts. This means that the parts are allowed to penetrate each other which can affect the accuracy of the simulation result. This paper presents a simple contact modeling technique that can be implemented in to MIC to avoid penetrations. The contact modeling consists of a contact detection and a contact equilibrium search algorithm. When implemented, MIC still only requires two finite element analysis (FEA) calculations. This paper describes the steps in the contact algorithm and how it can be used in MIC, and finally the proposed contact modeling is verified by comparing the simulation result with commercial FEA software ABAQUS contact algorithm.
18
Azabache Requena, Javier Armando, and Ronald Wilmer Marcial Ramos. "Characterization of preening from male Leistes bellicosus at Jaén airport, Perú." Manglar 19, no. 3 (October 3, 2022): 285–90. http://dx.doi.org/10.17268/manglar.2022.036.
Full textAbstract:
Preening in birds is a biologic aspect very important, its allow to ensure their welfare through the maintenance from external parts of theirs body. In relation to that was numerically characterized the preening of male Leistes bellicosus (specie most hit by airplanes Jaen aerodrome), between February and July 2022 at Jaén airport. A continuous recording for 2 hours and focal behavior for 5 minutes was performed, also using the fuzzy logic algorithm and exploratory analysis to measure this behavior. The preening is characterized by having a frequency between 1-4times/5minutes, a duration concentrated mainly between 1-50 seconds and an intensity of 4.7 points (Membership function=0.8). These variables have no correlation with temperature, humidity, wind speed and cloudiness. The wings and the back are the structures that are most cleaned (29 and 21 times/80 observations, respectively).
19
Zotin, N. A., and E. P. Lisman. "Designing of control and expulsion equipment for the pitot-static system of passenger airplanes." VESTNIK of Samara University. Aerospace and Mechanical Engineering 20, no. 2 (July 9, 2021): 36–44. http://dx.doi.org/10.18287/2541-7533-2021-20-2-36-44.
Full textAbstract:
The article discusses the issue of automating the serial process of bleeding and control of the pitot- static system of passenger airplanes. A functional diagram and basic design of some parts of the combined equipment are proposed. This equipment makes it possible to alternate the above-mentioned operations with great effectiveness. At the system control stage, the pressure or vacuum in it is created by a pressure-vacuum pneumatic unit. This pneumatic unit consists of a compressor and a set of electromagnetic valves that allow the compressor to be connected to the pumping or scavenging line. The value of the generated pressure is regulated by the flow rate in the pressure/scavenging channel and in the venting channel. Simulation of changes in ambient temperature is achieved due to blowing heated or cooled air over the temperature sensors of the aircraft. Pressure or vacuum in the controlled system is created in turn, in each of its lines. At the expulsion stage, a compressed-nitrogen cylinder acts as the pressure source. The pressurized gas passes through the pitot and is released into the atmosphere, cleaning out the contaminations. No manual operations are required for installing and removing connection hoses after connecting the proposed combined equipment to the pitot-static system. Remote-controlled electromagnetic valves connect the channels of the controlled system to the pressure-vacuum pneumatic unit and the source of compressed nitrogen. This reduces the duration of successive operations for the systems maintenance.
20
Blass, David, Sebastian Nyga, Bernd Jungbluth, Hans-Dieter Hoffmann, and Klaus Dilger. "Composite Bonding Pre-Treatment with Laser Radiation of 3 µm Wavelength: Comparison with Conventional Laser Sources." Materials 11, no. 7 (July 16, 2018): 1216. http://dx.doi.org/10.3390/ma11071216.
Full textAbstract:
To use the full potential of composite parts, e.g., to reduce the structural weight of cars or airplanes, a greater focus is needed on the joining technology. Adhesive bonding is considered favorable, superior joining technology for these parts. Unfortunately, to provide a structural and durable bond, a surface pre-treatment is necessary. Due to its high integration potential in industrial process chains, laser radiation can be a very efficient tool for this purpose. Within the BMBF-funded (German Federal Ministry of Education and Research) project GEWOL, a laser source that emits radiation at 3 µm wavelength (which shows significant advantages in theory) was developed for a sensitive laser-based bonding pre-treatment. Within the presented study, the developed laser source was compared with conventional laser sources emitting radiation at 355 nm, 1064 nm, and 10,600 nm in terms of application for a composite bonding pre-treatment. With the different laser sources, composites were treated, analytically tested, subsequently bonded, and mechanically tested to determine the bonding ability of the treated specimens. The results show a sensitive treatment of the surface with the developed laser source, which resulted in a very effective cleaning, high bonding strengths (over 32 MPa), and a good effectiveness compared with the conventional laser sources.
21
Kasem, M. M. "Analysis, control, and optimization of aeroelastic systems: an introduction to the recent literature for the new investigator." Journal of Physics: Conference Series 2299, no. 1 (July 1, 2022): 012005. http://dx.doi.org/10.1088/1742-6596/2299/1/012005.
Full textAbstract:
Abstract Aeroelasticity studies the static and dynamic interaction between structural deformation and fluid forces. As a result, the aeroelasticity is usually divided into three parts: aerodynamics, structural response, and dynamics with statics as a special case. Instabilities may occur to this interaction (feedback) that lead to structural failure and, even when no instability occurs, the interaction may lead to degradation or improvement of the system performance. There are several unstable phenomena may occur for elastic bodies such as flutter, divergence, low cycle oscillation, buffet, and control surface reversal. These unstable phenomena can be classified as dynamic or static. The present work provides a tutorial for those newly encountering aeroelasticity and a review of the recent literature from this century (after 2000). This includes mathematical modelling and its applications to airplanes, rotor blades, energy harvesting, and the control, and optimization of aeroelastic systems. Recent research advances are summarized and some suggestions for future work are made.
22
Łapka, Piotr, Marije Bakker, Piotr Furmański, and Hans van Tongeren. "Comparison of 1D and 3D thermal models of the nacelle ventilation system in a small airplane." Aircraft Engineering and Aerospace Technology 90, no. 1 (January 2, 2018): 114–25. http://dx.doi.org/10.1108/aeat-09-2015-0204.
Full textAbstract:
Purpose Insight in the temperature distribution on the internal and external surface of the nacelle is of great importance during the design phase of an aircraft. However, detailed information is not always needed. In a preliminary project stage or during parametric optimization, short analysis times are often more crucial than high accuracy. In such cases, the global insight in the temperature levels suffices to gain understanding of the relevance and influence of certain parameters. Nevertheless, estimating the maximum temperature for the most adverse conditions should also be done before a prototype is built. Therefore, this study aims to present and compare a simplified and an advanced methodology for the analysis of engine bay cooling and ventilation systems as well as heat transfer in the nacelle in a small airplane equipped with a turboprop engine in the tractor arrangement. Design/methodology/approach Both approaches included conductive, convective and radiative heat transfer in the engine bay of the small airplane I-23 as well as heat conduction in the nacelle made of material with anisotropic thermal conductivity. The one-dimensional (1D) model assumed that the nacelle with the air flow and engine was represented by a lumped thermal model in which heat was exchanged between the different lumped segments (the nodes) and the flowing air and engine. The three-dimensional (3D) model was based on the continuous control volume approach for heat, fluid flow and thermal radiation as well as on realizable k-ε turbulence model. Both models used commercial software. Findings The temperature distribution at the internal and external surface of the top nacelle was calculated. The 1D model predicted a temperature per node (per segment) while the 3D model was able to determine its values accurately and find the location of hot spots. Considering the complex geometry of the engine bay and nacelle and the assumed simplification, the obtained 1D and 3D results agreed quite well. Practical implications Both models will help in the development of new ventilation and cooling systems of the engine bay and nacelle as well as in the selection of materials for parts of the top cowling in the newly redesigned airplane I-23 equipped with a turboprop engine. In addition, the methodology presented in this paper might be applied in the development of other airplanes. Originality/value The 1D and 3D models of complex heat transfer inside the engine bay and in the nacelle of the newly re-designed airplane I-23 were elaborated and compared.
23
Poolperm, Pattarawadee, and Wasawat Nakkiew. "Effect of Porosity on Residual Stress of 2024-Aluminum GTAW Specimen." Materials Science Forum 872 (September 2016): 28–32. http://dx.doi.org/10.4028/www.scientific.net/msf.872.28.
Full textAbstract:
Aluminum alloys are used widely in many applications due to its low in density which can lead to a lightweight product. A high percentage of Cu in the chemical composition of the 2024 aluminum alloys helps withstand the occurrence of corrosion as well. Thus, aluminum alloy grade 2024 is used as a material for several parts in aircraft and spacecraft components, (e.g. the body of commercial airplanes), as well as parts in many other applications. Gas Tungsten Arc Welding (GTAW) is used widely in joining material parts together. Inappropriate welding parameters usually cause problems such as porosity in the welding. The occurrence of porosity is undesirable in welding because it can affect the strength of the welding area as well as other properties. Tensile residual stress near the surface of the material expedites the fatigue crack initiation. The relationship of porosity and residual stress for GTAW parts was very limited in literatures. Therefore, the objective of this research was to investigate the relationship of porosity to the occurrence of residual stress after the welding process. Full factorial design of experimental technique was used for setting up welding conditions of the GTAW. The specimen with highest porosity was selected for further analysis of its effect on residual stress. Porosity was analyzed by the radiographic testing (RT) and the residual stress was measure by X-ray diffraction (XRD) using sin2 method. The results showed that the highest porosity in the welded bead was found at the current of 130 A, the welding speed of 210 mm./min., and the wire feed rate of 700 mm./min. The results also suggested that lower current and welding speed caused an increase in porosity. The residual stress results on both longitude and transverse directions showed tensile residual stress at locations around the welded bead area.
24
Darji, Yashesh, and Dilip Patel. "Effect of Nano Reinforcement on Aluminium Metal Matrix Composites: A Review." ECS Transactions 107, no. 1 (April 24, 2022): 939–46. http://dx.doi.org/10.1149/10701.0939ecst.
Full textAbstract:
The developing prerequisite for the item having ease alongside amazing quality has encouraged work towards composites of materials lately. Which are having particular stages and qualities just as better than the parent materials. Metal Matrix composites (MMCs) are continually advancing because of inventive and energizing advances and are broadly utilized just as perceived as a possible material for some mechanical applications in different industry. This examination represents applications of aluminum compound primary parts are numerous in vehicles, airplanes, and other military components because of their improved properties and solidarity to weight proportions. New class of AMMC are in consideration wide cluster of utilizations in ventures due to great mechanical attributes, ease, and light weight. Aluminum Metal Matrix composites likewise can be made through an assortment of methods. By various strategy for the manufacture cycle and by adding the diverse support material, distinctive trademark profile got. Objective of this investigation is to study about of creation measure and different components, which are affecting of nano reinforcement on Aluminum Metal Matrix composites.
25
Belan, Juraj, Lenka Kuchariková, Magdalena Mazur, Eva Tillová, and Mária Chalupová. "Fatigue Characteristics of Materials Used in Transport Industry Applications." System Safety: Human - Technical Facility - Environment 1, no. 1 (March 1, 2019): 810–18. http://dx.doi.org/10.2478/czoto-2019-0104.
Full textAbstract:
AbstractDesigners have a major interest about fatigue properties of materials used in transport industry. Each component in transport works under alternating stress. From this point of view the fatigue properties are important for single parts lifetime resulting into safety of whole components as cars and airplanes what leads to safety on the roads or air and have influence on human life as well. Therefore this paper deals with fatigue properties of wrought Inconel alloy IN 718 and aluminum cast alloy AlSi9Cu3. Both materials were put on fatigue push – pull test, but Ni – based IN 718 alloy at frequency of loading around 20 000 kHz (High Frequency High Cycles Fatigue) and aluminum alloy AlSi9Cu3 at frequency of loading around 80 Hz (Low Frequency High Cycles Fatigue). These parameters were chosen with respect of usage such materials for production of components used in transport industry applications. Results after fatigue tests are presented as Wohler curve. For prediction of source of fracture the SEM fractography analysis of fatigue fracture surfaces was made.
26
Mrdak, Mihailo, Bojan Medjo, Darko Veljić, Miodrag Arsić, and Marko Rakin. "The influence of powder feed rate on mechanical properties of atmospheric plasma spray (APS) Al-12Si coating." REVIEWS ON ADVANCED MATERIALS SCIENCE 58, no. 1 (January 1, 2019): 75–81. http://dx.doi.org/10.1515/rams-2019-0007.
Full textAbstract:
Abstract In this paper, structural and mechanical properties of APS - atmospheric plasma spray coating Al-12Si are presented. The aim of the research was the optimisation of the flow of powder to produce layers with optimal mechanical and structural properties that will be applied to the worn out parts of airplanes. Three groups of samples were produced, by utilising three powder feed rates: 30 g/min, 45 g/min and 60 g/min. Evaluation of layers’ microhardness was done using HV0.3 method and the bond strengthwas determined by testing of tensile strength. Surface morphology of the deposited powder particles was examined on SEM (Scanning Electron Microscope). The microstructure of the coating with the best measured mechanical properties was subsequently examined in etched condition on optical microscope and SEM (in accordance with the standard PN 585005, Pratt & Whitney). Also, fracture morphology of this coating in deposited state was examined using SEM. It was found that powder feed control with atmospheric plasma spraying can produce dense layers of Al-12Si coating with good bond strength.
27
Zhang, Yang, Wei Liu, Yongkang Lu, Xikang Cheng, Weiqi Luo, Hongtu Di, and Fuji Wang. "Accurate profile measurement method for industrial stereo-vision systems." Sensor Review 40, no. 4 (June 15, 2020): 445–53. http://dx.doi.org/10.1108/sr-04-2019-0104.
Full textAbstract:
Purpose Profile measurement with boundary information plays a vital role in the detection of quality in the assembly of aviation parts. The purpose of this paper is to improve the evaluation accuracy of the aerodynamic shapes of airplanes, the profiles of large-sized parts need to be measured accurately. Design/methodology/approach In this paper, an accurate profile measurement method based on boundary reference points is proposed for the industrial stereo-vision system. Based on the boundary-reference points, the authors established a priori constraint for extracting the boundary of the measured part. Combining with the image features of background and the measured part, an image-edge compensation model is established to extract the boundary of the measured part. The critical point of a laser stripe on the edge of the measured part is extracted corresponding to the boundary constraint. Finally, as per the principle of binocular vision, the profile of the measured part is reconstructed. Finding Laboratory experiments validate the measurement accuracy of the proposed method which is 0.33 mm. In the analysis of results between the measured data and the theoretical model, the measuring accuracy of the proposed method was found to be significantly higher than that of the other traditional methods. Practical implication An aviation part was measured in the part-assembly shop by the proposed method, which verified the feasibility and effectiveness of this method. The research can realize the measurement of smooth surface boundary which can solve existing profile reconstruction problems for aviation parts. Originality/value According to the two-dimensional contour constraint, critical points of the laser strip sequence at the edge of measured part are extracted and the accurate profile reconstruction with the boundary is realized.
28
Донець, Олександр Дмитрович, Олександр Іванович Семенець, Євген Тимофійович Василевський, Олександр Григорович Гребеніков, and Андрій Михайлович Гуменний. "КОНСТРУКТИВНО-ТЕХНОЛОГІЧНІ РІШЕННЯ ЗАБЕЗПЕЧЕННЯ СТАТИЧНОЇ МІЦНОСТІ ТА РЕСУРСУ РЕГІОНАЛЬНИХ ПАСАЖИРСЬКИХ ЛІТАКІВ." Open Information and Computer Integrated Technologies, no. 82 (December 19, 2018): 4–26. http://dx.doi.org/10.32620/oikit.2018.82.01.
Full textAbstract:
Ensuring flight safety and aircraft structure lifetime is important today’s problem in development of up-to-date regional passenger aircraft. This paper deals with the aspects of providing static strength and lifetime of regional passenger aircraft. A series of factors and parameters were analyzed, which affect the aircraft static strength, lifetime, such as: fatigue, corrosion, wear, fretting-corrosion, human factor.n To ensure static strength, operational and design loads were determined for the entire range of design speeds and flight altitudes, overloads, aircraft weights and CG positions, fuel weight, cargo weight and various possible combinations of their distribution, taking into account the following: dynamic load and elastic characteristics of the aircraft’s design flying in disturbed air and while landing; dynamic load of the control system structure during maneuvering and under wind gusts; failures and malfunctions of systems that directly affect the strength characteristics. The results of flight tests showed that the An-148 100 / An-158 typical structure under the terms of static strength does not have features and parts that create emergency conditions or are unreliable, and confirmed the correctness of the choice of the established operational limitations presented for inclusion in the Flight Operation Manual. Conditions for operation of the An-148-100 / An-158 family during a design life of 30 years were determined on the basis of a comparative analysis of the corrosion resistance of the aircraft structures, whose service life exceeds 30 years. An-148-100 / An-158 airplanes are designed and manufactured in all-climate version in compliance with all the requirements for anti-corrosion protection. The aircraft used design and technological solutions to protect against loss of strength during operation from weathering, corrosion and abrasion, which allowed to state that the main power elements of the An-148-100 / An-158 aircraft typical structure are protected from reduction or loss of strength in operation for any reason, including weathering, corrosion and abrasion, as well as adequate ventilation and drainage. The provision of static strength and lifetime of regional passenger aircraft is confirmed by static, fatigue and flight tests of airplanes, reflected in technical reports with regard to strength, lifetime and service life of the An-148-100 / An-158 aircraft.
29
Siyaev, Aziz, and Geun-Sik Jo. "Towards Aircraft Maintenance Metaverse Using Speech Interactions with Virtual Objects in Mixed Reality." Sensors 21, no. 6 (March 15, 2021): 2066. http://dx.doi.org/10.3390/s21062066.
Full textAbstract:
Metaverses embedded in our lives create virtual experiences inside of the physical world. Moving towards metaverses in aircraft maintenance, mixed reality (MR) creates enormous opportunities for the interaction with virtual airplanes (digital twin) that deliver a near-real experience, keeping physical distancing during pandemics. 3D twins of modern machines exported to MR can be easily manipulated, shared, and updated, which creates colossal benefits for aviation colleges who still exploit retired models for practicing. Therefore, we propose mixed reality education and training of aircraft maintenance for Boeing 737 in smart glasses, enhanced with a deep learning speech interaction module for trainee engineers to control virtual assets and workflow using speech commands, enabling them to operate with both hands. With the use of the convolutional neural network (CNN) architecture for audio features and learning and classification parts for commands and language identification, the speech module handles intermixed requests in English and Korean languages, giving corresponding feedback. Evaluation with test data showed high accuracy of prediction, having on average 95.7% and 99.6% on the F1-Score metric for command and language prediction, respectively. The proposed speech interaction module in the aircraft maintenance metaverse further improved education and training, giving intuitive and efficient control over the operation, enhancing interaction with virtual objects in mixed reality.
30
Askeland, Bjarte. "Liability for Means of Mass Transportation in Scandinavia." Journal of European Tort Law 9, no. 2 (September 4, 2018): 170–91. http://dx.doi.org/10.1515/jetl-2018-0109.
Full textAbstract:
Abstract The article presents an overview of Norwegian law with regard to damages caused by means of mass transportation by buses, railways and airplanes. The author explains why and how in Norway, as elsewhere in Scandinavia, there is strict liability for damages caused by means of mass transportation. Also the assessment of damages in the mentioned categories is discussed. For personal injuries there are no caps for trains or buses, partly because a greater part of the loss of income is covered by social security benefits, something which is typical of the ‘Nordic model’. Along the same lines, the rules on contributory negligence favour the victim somewhat more than in other parts of Europe, with regard to accidents caused by both buses and trains. Hence the law is all in all rather friendly to the victim. As for damage caused by air traffic, there are tensions between the ‘victim-friendly’ attitude and the relevant EU regulations which make the Montreal Convention applicable to Scandinavian law. These tensions are discussed towards the end of the article. Thus the article highlights and illustrates how the Scandinavian legal culture with the ‘Nordic Model’ as its special hallmark endorses solutions that somewhat contradict the common solutions in continental Europe and in the UK.
31
Tu, Qing Song, Wei Min Zhang, Li Huang, Cheng Feng Chen, and Qiu Yong. "A New Non-Destructive Testing Method Used in the Axle of Landing Gear." Applied Mechanics and Materials 80-81 (July 2011): 1150–54. http://dx.doi.org/10.4028/www.scientific.net/amm.80-81.1150.
Full textAbstract:
The relations between stresses and leakage magnetic signal of concentration area of the airplane’s landing gear under varying load were studied. The finite element method was used to calculate the stress of axle under different conditions; An experiment was designed to simulate the stress status under the bending moment, the slight magnetic signals on specimen were measured, and the relation of the signals and stress was studied. The new testing method was explained with the theory of ferromagnetic and the significance of this technique for detecting defects of the airplane structural part was discussed. The safety of airplane’s main bearing parts plays an important role during its operation and it often comes to bad situation of fatigue damage for stress concentration [1, 2]. To prevent the breaking down of structural parts and get rid of big accidents, it becomes important and necessary to find out the early concentration and damage zone, and to make some certain examination of damage and stress status [3]. The method of magnetic memory testing would be effective for the confirming of stress concentration zone in the equipment or structural parts, and could lead the way ahead the matters of fatigue analysis, evaluation of equipment life and technological design. The method can detect the endurance failure of the airplane’s undercarriage shaft, which is composed of ferromagnetic materials, and that provides the experimental basis for the prevention of parts’ fatigue defects.
32
Донець, Олександр Дмитрович, Олександр Захарович Двейрін, Євген Тимофійович Василевський, Сергій Андрійович Філь, Олександр Григорович Гребеніков, and Андрій Михайлович Гуменний. "ПРОЕКТНО-КОНСТРУКТОРСЬКІ ОСОБЛИВОСТІ ПЛАНЕРУ РЕГІОНАЛЬНОГО ПАСАЖИРСЬКОГО ЛІТАКА." Open Information and Computer Integrated Technologies, no. 83 (May 23, 2019): 4–27. http://dx.doi.org/10.32620/oikit.2019.83.01.
Full textAbstract:
The design features of the regional passenger aircraft airframe, which were introduced at the stages of developing the An-148/An-158 aircraft family, are described. The design and construction works on the airframe, which were aimed at the implementation of the airframe design concept, based on the principle of a safely damaged structure, are given. The An-148/An-158 airplanes were designed using modern computer-aided design systems. The work performed provides aeroelastic stability for all configurations and all design conditions. When creating a family of regional passenger airplanes, a number of new design and technological solutions were applied to the airframe design (fuselage, wing, pylons of powerplants and tail assembly), in particular: the scope of composite materials (CM) application was expanded, including the fuselage beamstructural elements; auxiliary power unit compartment is made entirely of CM; fastening the skin to the fuselage frame is made using rivets with a compensator, which ensures high quality of the external surface and eliminates the need for milling the heads of rivets after their installation; the fuselage canopy frame was made by welding, which significantly simplified the assembly technology; a two-support connected hitch scheme and control of extension of the slat sections with the use of involute gearing in the slat extensionretraction drives on the hinge mechanisms in the form of a pair of gears – a gear rack; developed a rational design of the wing box with a theoretical surface of double curvature, high adaptability and operability with survivability and high lifetime; a seven-part flap extension-retraction mechanism has been developed, which provides a predetermined flap advancement path; a combined flap design with a metal torsion box part, nose and tail part and a deflector made of CM; a molybdenum coating was applied, which increased the wear resistance of high-loaded parts from titanium alloys by more than 20 times; a monolithic integral design of interceptors and ailerons from CM was developed; a rational design of a pylon of a hinge plate of a mid-flight power plant has been developed with optimal rigidity characteristics to achieve given characteristics of flutter safety, with extensive use of composite materials in the tail and nose sections; the design of caps from pressed semi-finished products with two tips has been developed; an integrated design of the rudder and elevator made of composite materials has been developed.
33
Saliba, Georges, Vincent Raimbault, Stéphane Colin, Ahmad Batikh, Stéphane Orieux, Rémi Gilblas, and Lucien Baldas. "Jet impingement cooling using fluidic oscillators: an experimental study." Journal of Physics: Conference Series 2116, no. 1 (November 1, 2021): 012028. http://dx.doi.org/10.1088/1742-6596/2116/1/012028.
Full textAbstract:
Abstract A growing portion of the thermal load on board airplanes is due to densely packed electronic systems. This increased thermal load along with constraints on weight and volume have made simple and reliable cooling solutions an urgent need in the aerospace industry. There is a wealth of cooling solutions available in order to meet these demands, the simplest and most adaptable of which is probably jet impingement cooling. In this study, fluidic oscillators capable of producing pulsating jets were used to cool a heated surface and were then compared to equivalent steady jets. Although pulsating jets can be produced using a number of devices, fluidic oscillators offer the advantage of not having any moving parts. These oscillators are sustained by a self-induced internal flow instability and can function at different scales. Although the major part of this work is based on prototypes that produce jets with sub-millimetric widths, designs at one tenth that scale, i.e. with an exit slot width of 50 µm, are also presented. Reynolds numbers ranging from ReD = 3500 to 5250 and jet-to-plate spacing from 1D to 10D were studied (where D is the initial width of the jet). The Nusselt number distribution is found for each case and a comparison is made between the performance of equivalent steady and pulsating jets based on the average Nusselt number.
34
IDRUS, NURFARAHIN, and NORIZAN MOHAMED. "FORECASTING THE NUMBER OF AIRPLANE PASSENGERS USING BOX-JENKINS AND ARTIFICIAL NEURAL NETWORK IN MALAYSIA." Universiti Malaysia Terengganu Journal of Undergraduate Research 2, no. 4 (October 31, 2020): 89–100. http://dx.doi.org/10.46754/umtjur.v2i4.183.
Full textAbstract:
Airline industry is one of the largest industries in the world of transport because it is the most important transport in the global transport system. The airline industry has played a very important role in the economic development in Malaysia. Due to the increase in its operating business, the demand for air travel increases day by day. Hence, this study focused on the number of passengers using air transport in Malaysia. The monthly data from January 2005 to December 2015 were obtained from Malaysia Airport Holdings Berhad (MAHB) in Sepang, Selangor. The data is divided into 2 parts, which are in sample data from January 2005 to December 2014 and out sample data from January 2015 to December 2015. The study was conducted to predict airline passengers in Malaysia using the Box-Jenkins model and Artificial Neural Network (ANN) model. Both models were studied to choose the best model. Mean Absolute Percentage Error (MAPE) and Mean Squared Error (MSE) were used to measure the performance of both models. SARIMA was selected as the best model for Box-Jenkins with MAPE and MSE were 7.3458388 and 2.67011 respectively while Multilayer Feed Forward Neural Network (MFFNN) with seven input variables, with MAPE and MSE, 7.251 and 0.0006 respectively were selected as the best model for Multilayer Feed Forward Neural Network (FFNN). In conclusion, these studies have proven that the Multilayer Feed Forward Neural Network (FFNN) model is the best model for considering airplanes in Malaysia compared to the SARIMA model.
35
Reichstein, Torben, Alois Peter Schaffarczyk, Christoph Dollinger, Nicolas Balaresque, Erich Schülein, Clemens Jauch, and Andreas Fischer. "Investigation of Laminar–Turbulent Transition on a Rotating Wind-Turbine Blade of Multimegawatt Class with Thermography and Microphone Array." Energies 12, no. 11 (June 1, 2019): 2102. http://dx.doi.org/10.3390/en12112102.
Full textAbstract:
Knowledge about laminar–turbulent transition on operating multi megawatt wind turbine (WT) blades needs sophisticated equipment like hot films or microphone arrays. Contrarily, thermographic pictures can easily be taken from the ground, and temperature differences indicate different states of the boundary layer. Accuracy, however, is still an open question, so that an aerodynamic glove, known from experimental research on airplanes, was used to classify the boundary-layer state of a 2 megawatt WT blade operating in the northern part of Schleswig-Holstein, Germany. State-of-the-art equipment for measuring static surface pressure was used for monitoring lift distribution. To distinguish the laminar and turbulent parts of the boundary layer (suction side only), 48 microphones were applied together with ground-based thermographic cameras from two teams. Additionally, an optical camera mounted on the hub was used to survey vibrations. During start-up (SU) (from 0 to 9 rpm), extended but irregularly shaped regions of a laminar-boundary layer were observed that had the same extension measured both with microphones and thermography. When an approximately constant rotor rotation (9 rpm corresponding to approximately 6 m/s wind speed) was achieved, flow transition was visible at the expected position of 40% chord length on the rotor blade, which was fouled with dense turbulent wedges, and an almost complete turbulent state on the glove was detected. In all observations, quantitative determination of flow-transition positions from thermography and microphones agreed well within their accuracy of less than 1%.
36
Chen, Lichao, Sudhir Singh, Thomas Kailath, and Vwani Roychowdhury. "Brain-inspired automated visual object discovery and detection." Proceedings of the National Academy of Sciences 116, no. 1 (December 17, 2018): 96–105. http://dx.doi.org/10.1073/pnas.1802103115.
Full textAbstract:
Despite significant recent progress, machine vision systems lag considerably behind their biological counterparts in performance, scalability, and robustness. A distinctive hallmark of the brain is its ability to automatically discover and model objects, at multiscale resolutions, from repeated exposures to unlabeled contextual data and then to be able to robustly detect the learned objects under various nonideal circumstances, such as partial occlusion and different view angles. Replication of such capabilities in a machine would require three key ingredients: (i) access to large-scale perceptual data of the kind that humans experience, (ii) flexible representations of objects, and (iii) an efficient unsupervised learning algorithm. The Internet fortunately provides unprecedented access to vast amounts of visual data. This paper leverages the availability of such data to develop a scalable framework for unsupervised learning of object prototypes—brain-inspired flexible, scale, and shift invariant representations of deformable objects (e.g., humans, motorcycles, cars, airplanes) comprised of parts, their different configurations and views, and their spatial relationships. Computationally, the object prototypes are represented as geometric associative networks using probabilistic constructs such as Markov random fields. We apply our framework to various datasets and show that our approach is computationally scalable and can construct accurate and operational part-aware object models much more efficiently than in much of the recent computer vision literature. We also present efficient algorithms for detection and localization in new scenes of objects and their partial views.
37
Shao-Hsien, Chen, and Kun-Tan Tsai. "Predictive Analysis for the Thermal Diffusion of the Plasma-Assisted Machining of Superalloy Inconel-718 Based on Exponential Smoothing." Advances in Materials Science and Engineering 2018 (2018): 1–9. http://dx.doi.org/10.1155/2018/9532394.
Full textAbstract:
Nickel base and titanium base materials have been widely applied to engines in aerospace industry, and these engines are essential components of airplanes. The machining characteristics of aerospace materials may cause machining cutters to be worn down in a short time and thus reduce the accuracy of processing. The plasma-assisted machining adopted in the research is a kind of the complex machining method. In the cases of nickel base and titanium base alloys, the method can heat workpieces in an extremely short duration to soften the materials for the ease of cutting so that the cutting force, cutter wear, and machining cost will all be reduced. The research adopted plasma heating to soften parts of the materials and aimed to explore the heating of nickel base alloy. The temperature variation of the materials was investigated and measured by adjusting the current and feed velocity. Moreover, Inconel-718 superalloy was adopted for the comparison with nickel base alloy for the observation of the influence and change brought by heat, and the method of exponential smoothing was adopted to conduct the prediction and analysis of thermal diffusion for understanding the influence and change brought by electric current on nickel base materials. Finally, given the current from 20 A to 80 A and feed velocity from 1,000 mm/min to 3,000 mm/min, the influence of thermal diffusion was investigated and the related model was built.
38
Harada, Yasunori, Makoto Ishida, and Katsuhiko Takahashi. "Formation of Fe-Al Intermetallic Compound Film on High-Speed Tool Steel by Shot Lining and Heat Treatment." Materials Science Forum 783-786 (May 2014): 1414–19. http://dx.doi.org/10.4028/www.scientific.net/msf.783-786.1414.
Full textAbstract:
Shot peening is widely utilized to improve the fatigue property of mechanical parts for transportation equipment such as cars and airplanes. Also, this technology is being applied as a film-forming technology in order to improve surface quality. The authors have recently proposed new joining methods using shot peening, shot lining. In this method, the metals are bonded with the dissimilar metal by applying plastic deformation and the pressure. The thin foil can be joined to the substrate surface by the pressure generated by the hit of the shots. In this study, the formation of an Fe-Al intermetallic compound film on high-speed tool steel by shot lining and heat treatment was investigated. In the experiment, a centrifugal-type peening machine with an electrical heater was employed. The shot medium was high-carbon cast steel. The substrate was a commercial high-speed tool steel JIS-SKH51, and the foil was commercially available pure aluminium. The shot lining process of tool steel with an aluminium foil was carried out at 573K in air using a peening machine. Heat treatment was performed at diffusion temperatures from 923 to 1573K in vacuum. The lined substrates exhibited a harder layer of aluminium-rich intermetallics in the diffusion temperature range of 923 to 1173K. When the temperature of the lined substrates was more than 1273K, the surface was covered with thicker and highly anticorrosive layers of iron-rich intermetallics. We found that the present method could be used for the formation of functional films on high-speed tool steel.
39
Thamm, F. P., N. Brieger, K. P. Neitzke, M. Meyer, R. Jansen, and M. Mönninghof. "SONGBIRD – AN INNOVATIVE UAS COMBINING THE ADVANTAGES OF FIXED WING AND MULTI ROTOR UAS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XL-1/W4 (August 27, 2015): 345–49. http://dx.doi.org/10.5194/isprsarchives-xl-1-w4-345-2015.
Full textAbstract:
This paper describes a family of innovative fixed wing UAS with can vertical take off and land – the SONGBIRD family. With nominal payloads starting from 0.5 kg they can take off and land safely like a multi-rotor UAV, removing the need for an airstrip for the critical phases of operation. A specially designed flight controller allows stable flight at every point of the transition phase between VTOL and fixed wing mode. Because of this smooth process with a all time stable flight, very expensive payload like hyperspectral sensors or advanced optical cameras can be used. Due to their design all airplanes of the SONGBIRD family have excellent horizontal flight properties, a maximum speed of over 110 km/h, good gliding properties and long flight times of up to 1 h. Missions were flown in wind speeds up to 18 m/s. At every time of the flight it is possible to interrupt the mission and hover over a point of interest for detail investigations. The complete flight, including take-off and landing can be performed by autopilot. Designed for daily use in professional environments, SONGBIRDs are built out of glass-fibre and carbon composites for a long service life. For safe operations comprehensive security features are implemented, for example redundant flight controllers and sensors, advanced power management system and mature fail safe procedures. The aircraft can be dismantled into small parts for transportation. SONGBIRDS are available for different pay loads, from 500 g to 2 kg. The SONGBIRD family are interesting tools combining the advantages of multi-copter and fixed wing UAS.
40
Scharvogel, Matthias. "Titanium Metal Injection Molding - A Commercial Overview." Key Engineering Materials 704 (August 2016): 107–12. http://dx.doi.org/10.4028/www.scientific.net/kem.704.107.
Full textAbstract:
Metal Injection Molding (MIM) of Titanium and its alloys has been the topic of many scientific research activities and presentations for many years. By now there are several companies that focus on applying the gained knowledge for producing Titanium MIM components in production quantities. This is only possible since Titanium powder in repeatable quality is available in production quantities and the specialized production equipment was developed over the recent years. Two ASTM standards for Titanium MIM implants have published and several Titanium MIM components have received approval around the globe, including approval by the Food and Drug Administration (FDA) for the United States. Based on this foundation, several large Medical Technology companies started developing next generation implants using MIM as the preferred production method in order to use the design advantages and / or reduce costs. The aerospace industry also started recognizing the advantages of Titanium MIM. There are several Titanium MIM parts that are already being used in commercial airplanes in production quantities. Additional applications in order to replace other materials, reduce costs or use the design advantages of MIM are currently being developed. The cost reduction related to Titanium MIM allows the usage of this great material in other industries like for sporting goods, outdoor equipment or luxury products. The Titanium MIM industry is slowly maturing and large companies started applying the great advantages into the product portfolio. It will be imperative that the relatively small Titanium MIM companies perform according to the high expectations of the large potential customers that would like to use the technology for future products.
41
Ciaburro, Giuseppe, Gino Iannace, and Amelia Trematerra. "Research for the Presence of Unmanned Aerial Vehicle inside Closed Environments with Acoustic Measurements." Buildings 10, no. 5 (May 23, 2020): 96. http://dx.doi.org/10.3390/buildings10050096.
Full textAbstract:
Small UAVs (unmanned aerial vehicle) can be used in many sectors such as the acquisition of images or the transport of objects. Small UAVs have also been used for terrorist activities or to disturb the flight of airplanes. Due to the small size and the presence of only rotating parts, drones escape traditional controls and therefore represent a danger. This paper reports a methodology for identifying the presence of small UAVs inside a closed environment by measuring the noise emitted during the flight. Acoustic measurements of the noise emitted by a drone inside a large environment (12.0 × 30.0 × 12.0 m) were performed. The noise was measured with a sound level meter placed at different distances (5, 10, and 15 m), to characterize the noise in the absence of anthropic noise. In this configuration, a typical tonal component of drone noise is highlighted at the frequency of one-third of an octave at 5000 Hz due to the rotation of the blades. This component is also present 15 m away from the source point. Subsequent measurements were performed by introducing into the environment, through a loudspeaker, the anthropogenic noise produced by the buzz of people and background music. It is possible to distinguish the typical tonal component of UAV noise at the frequency of 5000 Hz even when the level of recording of anthropogenic noise emitted by the loudspeaker is at the maximum power tested. It is therefore possible to search for the presence of small UAVs inside a specific closed environment with only acoustic measurements, paying attention to the typical frequency of noise emission equal to 5000 Hz.
42
Paulo, Rui Miguel Ferreira, Pierpaolo Carlone, Robertt A. F. Valente, Filipe Teixeira-Dias, and Gaetano S. Palazzo. "Integrated Design and Numerical Simulation of Stiffened Panels Including Friction Stir Welding Effects." Key Engineering Materials 554-557 (June 2013): 2237–42. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.2237.
Full textAbstract:
Stiffened panels are usually the basic structural building blocks of airplanes, vessels and other structures with high requirements of strength-to-weight ratio. They typically consist of a plate with equally spaced longitudinal stiffeners on one side, often with intermediate transverse stiffeners. Large aeronautical and naval parts are primarily designed based on their longitudinal compressive strength. The structural stability of such thin-walled structures, when subjected to compressive loads, is highly dependent on the buckling strength of the structure as a whole and of each structural member. In the present work, a number of modelling and numerical calculations, based on the Finite Element Method (FEM), is carried out in order to predict the ultimate load level when stiffened panels are subjected to compressive solicitations. The simulation models account not only for the elasto-plastic nonlinear behaviour, but also for the residual stresses, material properties modifications and geometrical distortions that arise from Friction Stir Welding (FSW) operations. To construct the model considering residual stresses, their distribution in FSW butt joints are obtained by means of a numerical-experimental procedure, namely the contour method, which allows for the evaluation of the normal residual stress distribution on a specimen section. FSW samples have been sectioned orthogonally to the welding line by wire electrical discharge machining (WEDM). Displacements of the relaxed surfaces are then recorded using a Coordinate Measuring Machine and processed in a MATLAB environment. Finally, the residual stress distribution is evaluated by means of an elastic FE model of the cut sample, using the measured and digitalized out-of-plane displacements as input nodal boundary conditions. With these considerations, the main goal of the present work will then be related to the evaluation of the effect of FSW operations, in the ultimate load of stiffened panels with complex cross-section shapes, by means of realist numerical simulation models.
43
Pietzka, Daniel, Nooman Ben Khalifa, Stephanie Gerke, and A. Erman Tekkaya. "Composite Extrusion of Thin Aluminum Profiles with High Reinforcing Volume." Key Engineering Materials 554-557 (June 2013): 801–8. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.801.
Full textAbstract:
Extruded aluminium profiles with a variety of different cross-sections are mainly used in lightweight structures for transportation means. Examples are stringer profiles in the fuselage of airplanes or profiles in chassis of trains and cars. Nowadays, the mass reduction of a lightweight structure is an important issue to achieve lower fuel consumption and CO2 emissions. With an increased portion of aluminium profiles the mass of structures can be reduced considerably in contrast to the application of steel parts, due to the lower density of aluminium. However, this is coupled with disadvantages such as the lower specific stiffness and strength of the material. One possibility to improve the mechanical properties of aluminium profiles without a considerable increase of their weight is the embedding of reinforcing elements during the extrusion process. Special porthole extrusion dies are used to feed reinforcing elements in form of high strength steel wires separate from the aluminium material flow. In the welding chamber of the die both materials bond together to a composite profile. To achieve a high advantage of the technology for lightweight applications a high reinforcing volume of aluminium profiles is targeted. A comparatively high reinforcing volume can be reached either by a high number of reinforcing elements or through a reduction of the profile wall thickness. A high number of reinforcing elements leads to a small distance between the single elements in the profile cross-section. The paper will show the results of an experimental and numerical analysis which were carried out to determine the minimum distance between the reinforcing elements as well as the minimum profile thickness. In the trials different arrangements of the elements in the profile cross-section and profile thicknesses were considered. Main parameters which have an influence on the process stability were analyzed and a process window for the manufacture of thin profiles with high reinforcing volume was deduced.
44
Hefti, Larry D. "Advances in the Superplastically Formed and Diffusion Bonded Process." Materials Science Forum 551-552 (July 2007): 87–93. http://dx.doi.org/10.4028/www.scientific.net/msf.551-552.87.
Full textAbstract:
The Superplastically Formed and Diffusion Bonded (SPF/DB) titanium structure in production today for Boeing products, not including engines, are all diffusion bonded using matched metal tooling and are all fabricated using the common 6Al-4V alloy. The matched metal tooling concept presents a challenge in obtaining high quality bonds over large areas where direct tool pressure is being used to place the titanium sheets into contact with each other. This is due to tolerance build-up in the tools and in the titanium sheets that are used to fabricate the components. Also, because the parts are partially formed before bonding begins, material has been pulled away from the bonding area and the thickness in that location is now less than what the tool was designed for which makes achieving a good quality bond even more challenging. Boeing Commercial Airplanes (BCA) is currently advancing the state of the SPF/DB process in several ways. One of these advances is using a different approach for diffusion bonding. The process includes using stop-off between the sheets and diffusion bonding the pack first and then superplastically forming the stiffening features. This generates a component that is very well bonded in the required locations. However, this process also has its challenges. One of these involves how to apply the stop-off material in the proper location using the most cost effective process. Historically, the application method has been silk screening. A new method has been developed for applying the stop-off that eliminates the need for several pieces of equipment that are required for the silk screening process as well as the associated floor space. Another advancement has been in the development of a different titanium alloy for use in SPF/DB structure.
45
Arfianto, Afif Zuhri, Mohammad Basuki Rahmat, Fuad Dhiyavia, Tri Budi Santoso, Nyoman Gunantara, Eko Supriyanto, and Valian Yoga Pudya Ardhana. "Autopilot Unmanned Smart Boat Vehicle (AUSV) Communication with LoRa RFM95." JOIV : International Journal on Informatics Visualization 4, no. 4 (December 18, 2020): 219. http://dx.doi.org/10.30630/joiv.4.4.492.
Full textAbstract:
Autopilot is a system control application on moving vehicles such as airplanes, helicopters, or boat, which serves to stabilize the direction of motion in the desired time and the programmed path's direction. the autopilot control system is controlled by a series of microcontrollers and GPS that has the function to be able to determine and the desired object. This control system is designed with electrical system controls that utilize microcontrollers, sensor and GPS as control media. The development of autopilot prototypes is used for testing new control algorithms and the reliability of other electronic components such as sensors and microprocessors. A control system is needed to control the boat to its destination. The relatively accurate system dynamics model affects the steering performance of the autopilot system. The system in question can be considered a boat with an actuator rudder, which experiences external disturbances. this system is broadly divided into two parts: the control station part and the autonomous boat part. These two parts communicate with each other using LoRa device. The data sent from the control station to the autonomous boat is target latitude and longitude coordinates. The autonomous boat will send feedback in the form of boat latitude and longitude coordinates so that users can find out the current location of the boat. Autonomous Boat also provides feedback to the control station via LoRa in the form of boat coordinates so that users can find out the current location of the boat and whether the boat has reached the specified coordinates. The control station will send feedback from the boat to a database that can be monitored via the website to find out the boat's current condition on the website. Based on the results that have been obtained in the analysis and testing of the system. GPS sensor used in autonomous boat Ublox NEO-7m has an accuracy level with an average distance value of 3.220921 meters with the lowest cold start time of 7 seconds. Compass sensor used in autonomous boat CMPS11 has an accuracy level with an average value of 3.041667 degrees. Communication distance between autonomous boat and control station using LoRa with 5dBi antenna can reach 1406.79 meters in condition without obstruction between nodes. Data delivery system can be successfully sent from user to autonomout boat and sending feedback back to user. Delay update of boat coordinate data on interface has the lowest average of 30.8 seconds. Based on turning circle test results, autonomous boat is able to create imperfect circles with a radius of 8,364 m.
46
Rajendran, Dorothy, Thankappan Sasilatha, Doss Amala, Rajendran Santhammal, Časlav Lačnjevac, and Gurmeet Singh. "Deep learning-based underwater metal object detection using input image data and corrosion protection of mild steel used in underwater study: A case study: Part A: Deep learning-based underwater metal object detection using input image data." Zastita materijala 63, no. 1 (2022): 5–14. http://dx.doi.org/10.5937/zasmat2201005r.
Full textAbstract:
Due to the importance of underwater exploration in the development and utilization of deep-sea resources, underwater autonomous operation is more and more important to avoid the dangerous high-pressure deep-sea environment. For underwater autonomous operation, intelligent computer vision is the most important technology. In an underwater environment, weak illumination and low-quality image enhancement, as a pre-processing procedure, is necessary for underwater vision. In this paper, introduced Deep learning-based Underwater Metal object detection using input Image data by using several step to improve the model performance. In this experimentation we are using TURBID dataset 100 images to validate the performance. And also we compare the performance result by given the input images in different validation level. In first input image is initially preprocessed and that images is given to the KFCM-Segmentation. The segmented images are given to the DWT Extraction to extract the features from those images. And finally the Convolution Neural Network (CNN) is used to classify the images to detect the objects. Also this proposed model attained the classification accuracy of 98.83%. This method is much suitable for detect the objects in underwater robotically. Metallic parts of machines of ships or airplanes may submerge in sea water. They may undergo corrosion when they come in contact with sea water which contains 3.5% sodium chloride. This is most commonly responsible for the corrosive nature of the seawater. The robots made of materials such as mild steel may also undergo corrosion when they come in contact with sea water, while is search. If a paint coating is given, it will control the corrosion of these proposed materials. Hence this work is undertaken. Mild steel is coated with Asian guard red paint. Corrosion resistance of mild in 3.5% sodium chloride solution is measured before coating and after coating by electrochemical studies such as polarization study and AC impedance spectra. The corrosion inhibition efficiency offered by red paint to mild steel in 3.5% sodium chloride is 99.98%.
47
Ahmad, Iram Raza, and Dong Wei Shu. "Tensile Properties of Die-Cast Magnesium Alloy AZ91D at High Strain Rates in the Range between 300 s-1 and 1500 s-1." Applied Mechanics and Materials 24-25 (June 2010): 325–30. http://dx.doi.org/10.4028/www.scientific.net/amm.24-25.325.
Full textAbstract:
Magnesium alloys have been increasingly used in the automobile, aerospace and communication industries due to their low density, high strength to weight ratio, good impact resistance and castability. Magnesium alloys, previously not used in load bearing components and structural parts are strongly being considered for use in such applications. Impact events in vehicles and airplanes as well as developments in weaponry and high speed metal working are all characterized by high rates of loading. Understanding of the dynamic behaviour of materials is critical for proper design and use in different applications. In the current study, a cast magnesium alloy AZ91D has been investigated at quasi-static and higher strain rates in the range between 300 s-1 and 1500 s-1. The INSTRON machine was used to perform the quasi-static tests. High strain rate tests have been performed using the Split Hopkinson Tensile Bar (SHTB), a very useful and widely used tool to study the dynamic behaviour of variety of engineering materials. The results of a tensile testing indicate that the tensile properties including yield strength (YS), ultimate tensile strength (UTS) and the elongation at fracture (Ef) are affected by the strain rate variation. Higher stresses are associated with higher strain rates. The alloy AZ91D displays approximately 45% higher tensile stresses at an average strain rate of approximately 1215/s than at quasi-static strain rate. The dependence of the yield stress and tensile strength on the strain rate in the range of high strain rate above 1000 s-1 is larger than that at lower strain rates. The alloy AZ91D is observed to be more strain rate sensitive for strain rate higher than 1000 s-1. A decrease in the strain rate sensitivity is also observed with the increasing strain in the specimen. It is observed that the hardening behaviour of the alloy is affected with increasing the strain rate. At high strain rates, the fracture of magnesium alloy AZ91D tends to transit from ductile to brittle.
48
Wang, Futong, Leilei Yan, Qi Jiang, and Xiaxin Tao. "Measurement and Numerical Simulation of Ground and Subgrade Vibrations of Beijing Urban Rail Line 13." Advances in Civil Engineering 2020 (February 24, 2020): 1–12. http://dx.doi.org/10.1155/2020/7219150.
Full textAbstract:
Urban rail transit is an effective way to deal with the problem of traffic congestion in major cities. Trains travel through dense residential and commercial areas, providing convenient transportation while also result in vibration problems in the surrounding environment. Long-lasting vibrations result in disturbance to people’s sleep, malfunction of sensitive equipment, and even damage to heritage buildings. Compared with elevated and tunnel sections, ground surface urban railway generates vibrations and propagates to the surroundings via a more direct path in the form of surface waves, which makes the environmental problem more prominent. Due to the complexity of the train-track-ground system, the characteristics of the vibration propagation and attenuation are yet to be revealed. In this paper, we investigate the vibration of the ground and the subgrade next to the Beijing Urban Rail Line 13 by a field measurement combined with a mathematical model. The duration of ground vibration is divided into two parts: the train passing time and the Doppler effect-related tailing part. Through a regression analysis of the duration, the train passing time is identified and the train traveling speed is estimated. The attenuation relationship of ground vibration intensity is expressed by a piecewise function. In the subgrade, the vibration intensity of particle decays with increasing depth and the stress decay rate is faster than that of the acceleration. The dynamic wheel/rail interaction behaves stationary and periodic, and the magnitude fluctuates up and down with the quasi-static axle weight. The intensity attenuation relationship fitted in this paper provides a basis for designing new lines and renewing old lines and can be used as a reference for the development of vibration-reduction technology. The simulated time history of the wheel-rail force provides an excitation sample for further model experiments and numerical simulation. The proposed train speed identification method may be useful for parameter identification of moving sources such as ships, automobiles, and airplanes.
49
Denisov, L. V., M. V. Siluyanova, V. V. Kuritsyna, and D. N. Kuritsyn. "Uniform Electrospark Surface Hardening of Airplane-Engine Parts." Russian Engineering Research 40, no. 3 (March 2020): 270–73. http://dx.doi.org/10.3103/s1068798x20030090.
Full text
50
Koreshkov, A. V., A. G. Boitsov, V. V. Kuritsyna, and M. V. Siluyanova. "Multicomponent and Multilayer Electrospark Alloying of Airplane Parts." Russian Engineering Research 41, no. 7 (July 2021): 653–56. http://dx.doi.org/10.3103/s1068798x21070145.
Full text