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Journal Article
Yibo Li, Efstratios Nikolaidis, Zissimos Mourelatos
This paper presents a methodology to evaluate and optimize discrete event systems, such as an assembly line or a call center. First, the methodology estimates the performance of a system for a single probability distribution of the inputs. Probabilistic Reanalysis (PRRA) uses this information to evaluate the effect of changes in the system configuration on its performance. PRRA is integrated with a program to optimize the system. The proposed methodology is dramatically more efficient than one requiring a new Monte Carlo simulation each time we change the system. We demonstrate the approach on a drilling center and an electronic parts factory.
Journal Article
Jayant Hemachandra Bhangale, Ashish Manohar Mahalle
RETRACTED: ABSTRACT Presently, most of the companies have combination of process and product layout. Cellular manufacturing is a place where company has established one or more manufacturing cells. Due to competition, Automobile industries are changing existing plant layout to “Cellular Layout” in which manufacturing process is carried out by proper arrangement of machines. This research paper aims at the optimization of cellular manufacturing layout using: cell formation stage, cell layout stage. In the first stage, a heuristic based upon the material flow is developed, which allows the machines to be clustered more naturally. In the second stage, a genetic algorithm is used to optimize the machine layout within each cell, in which a previously defined material handling system is provided. This representation allows the design of the layout and aisle-structure simultaneously, and can be converted into a string representation adaptable by a genetic algorithm for optimization.
Journal Article
Ala Qattawi, Mahmoud Abdelhamid, Ahmad Mayyas, Mohammed Omar
1 The manufacturing of Origami based sheet metal products is a promising technology, mostly in terms of reducing the tooling and process complexity. This procedure can also be called fold forming, as it depends on exclusively shaping the required geometry via sequence of bends. However, the design analysis and modeling of folded sheet metal products are not fully mature, especially in terms of determining the best approach for transferring the analysis from a three-dimensional (3D) to a two-dimensional (2D) context. This manuscript discusses the extension of the Origami technique to the fold forming of sheet metal products represented in modeling approach and design considerations for the topological variations, the geometrical validity, and the variance of stress-based performance. This paper also details the optimization metrics that were developed to reflect the design and manufacturing differences among the possible topological and geometrical options for a single part design.
Journal Article
Salah A. Elmoselhy
The lean production system has been successful in the cost-based winning order criterion markets. However, the automotive market has been volatile and the new criterion of winning orders has been availability, which has called for an agile system. The present paper argues that because of fierce competition the current automotive market winning order criterion is now a blend of cost and availability. It shows how a hybrid lean-agile system can strategically meet such a challenging criterion. The study presents the drivers, attributes and providers in lean manufacturing, agile manufacturing, and hybrid lean-agile manufacturing systems. It investigates how the strategic facet of the proposed hybrid lean-agile manufacturing system addresses the six manufacturing competitive dimensions. It presents as well the hybrid lean-agile manufacturing key performance indicators.
Journal Article
Akram Faqeeh, Ahmed Sherif El-Gizawy
The present paper aims at optimization of multiple quality characteristics (dimensional accuracy and surface roughness) in dry drilling Ti-6Al-4V using TiAlN-coated carbide tool while the controllable factors are spindle speed and feed rate. To do so, desirability methodology is used to explore optimum conditions for concurrent optimization of the addressed quality characteristics. Central composite design (CCD) is used for experimentation. In order to create reliable models describing the process behavior, response surface methodology (RSM) is used.
Technical Paper
Swapnil Pawar, Sandip Patil, Suhas Joshi, Rajkumar Singh
Abstract Tapping is an important process in assembly of aircraft structures because on an average one millions of tapped holes are made on an aircraft structure. However, sudden breakage of the tap is the most undesirable event frequently encountered during the tapping process. In particular, this can mostly occur when small diameter internal threads are made in a ‘difficult-to-cut’ material like titanium. For this reason, it has been a topic of industrial interest in the manufacturing sector for many years. The ultrasonic vibrations assisted tapping (UVAT) is a novel manufacturing technology, where ultrasonic vibrations are provided to the work piece in the axial direction. The present work is a comprehensive study involving experimental characterization. The experimentation shows that UVAT reduces the torque during tapping as compared to that of in conventional process. There is a 19.1% reduction in torque and about 20.3% reduction in cutting temperature in UVAT over that of in CT.
Journal Article
Branislav Sredanovic, Djordje Cica
Abstract The most efficient way to reduce friction and heat generation at the cutting zone is to use advanced cooling and lubricating techniques. In this paper, an experimental study was performed to investigate the capabilities of conventional, minimal quantity lubrication (MQL) and high pressure cooling (HPC) in the turning operations. Process parameters (feed, cutting speed and depth of cut) are used as inputs to the developed artificial neural network (ANN) and the adaptive networks based fuzzy inference systems (ANFIS) model for prediction of cutting forces, tool life and surface roughness. Results obtained by the models have been compared for their prediction capability with the experimentally determined values and very good agreement with experimental results was observed.
Technical Paper
Thomas J. Hagale
There are a large number of space structures, orbital replacement units (ORUs) and other components that must be transported to orbit on a regular basis for the assembly and maintenance of the International Space Station (ISS). Some of this hardware will be ferried on the Spacelab Logistics Pallet (SLP), which has a long and reliable history of space flight successes. The carrier is well used, well qualified, and very adaptable for repeated use in accommodating cargoes of various sizes and shapes. This paper presents an overview of past, present and future hardware design solutions that accommodate EVA operations on the SLP. It further demonstrates how analysis techniques and design considerations have influenced the hardware development, EVA operations, and compliance with human engineering requirements for the SLP.
Types of aircraft passenger-escape systems An overview of existing and potential new methods for assuring aircraft occupant safety. SAE Skill India Initiative: S2I2 A new SAEINDIA collaboration aims to help young engineers acquire "industry-ready" skills. A technology-driven sustainable-agriculture solution Pumping more air into the cylinder is key to solving the CAFE puzzle, and engineers are hard at work figuring out the best ways to do it with turbocharger and supercharger innovation. Rotorcraft icing computational tool development 3D printing machines can't be built fast enough In the additive-manufacturing world, the costs of components are dropping, the technology is becoming more reliable and parts are fabricated faster, allowing industries beyond aerospace to adopt additive technologies, says Oak Ridge Lab's Ryan Dehoff.
Focus on advanced safety systems and human-factor interventions The impact of REACH on the aviation sector Considered the most comprehensive chemical-regulation legislation to date, REACH presents serious ramifications for the aircraft industry. Lightweighting: What's Next? Experts weigh in on the challenges and future enablers in the battle to reduce vehicle mass. The best of COMVEC 2016 Autonomous vehicles and improved fuel efficiency via advanced powertrain solutions are pressing topics detailed in this select group of technical papers from the SAE Commercial Vehicle Engineering Congress. Optimizing waste heat recovery for long-haul trucks Autonomous solutions in agriculture Downsizing a HD diesel engine for off-highway applications Zero-emissions electric aircraft: Theory vs. reality
Automation usage soars in aerospace Robots and other automated equipment are becoming simpler to program and set up, making them better suited for aerospace use.
Putting CAE to work for non-experts CAE suppliers respond to the need to do more with less in a number of ways, including guided work flows and role-specific interfaces.
The big boys go for plastic While it is true that the latest developments in advanced alloy manufacturing techniques can deliver structures and components that meet all the product requirements that aerospace primes need for new aircraft, there can be no escaping the fact that there is now an unstoppable momentum building up for the plastic airplane.
Efficient, low-cost power converters for EVs Losses when power converters change the currents, voltages, and frequencies of electrical fees mean efficiencies are in high demand for EVs and everything else electric.
Joining metal/composite structures The interference-fit bolted joining of hybrid metal/composite can greatly improve the fatigue life of such joints, according to Chinese researchers.
A paradigm shift in offline programming of robots CAD-based offline programming has the potential to take into account design changes to a certain extent, avoiding time-consuming and thus expensive reprogramming after an engineering design change.
Everything's looking up for aircraft with Internet connections Satellites will make global connectivity possible. Composite bonds put to the test The application of adhesive bonding as a joining technology for CFRP aircraft structures is essential for the realization of novel lightweight design concepts. Aerospace leads in additive manufacturing The unique advantages of making metal parts from powder-bed additive manufacturing are looking attractive to engine manufacturers. Europe's aerospace sector at a crossroads Europe is facing a massive black hole in its future defense procurement portfolio. What will replace today's fighters and trainers when the present order backlogs have been produced?
The row about rare earths Rare-earth elements are key to applications as varied as traction motors, catalytic converters, and wind turbines, but high prices and supply shortages have the auto industry grappling with design changes and other alternatives.
Machine tools meet new materials If you're in the business of making machine tools for aerospace applications, you're probably working on improvements in cutting tough metals and composites.
Finding success on an international track Student members of the University of Missouri's Formula SAE team are learning firsthand that international collaboration is the future of engineering. A vision. A car. A cause. New Mexico State Aggies are tough enough to race pink. CyberAuto Challenge helps close talent gap Having a supply of high-quality young engineers is key to beefing up the automotive industry's cyber defenses.
UMich-Ann Arbor team takes home Baja season's Iron Team Award Cornell University also had a strong 2014 season, but not strong enough to fend off Michigan Baja Racing. Georgia Tech and Warsaw University were double-winners at SAE Aero Design competitions University of Akron and University of Cincinnati were the other winners at the twin 3-class competitions, the former setting a record in the process. West Coast teams win 2 of 3 Formula SAE events Oregon State captures its fifth crown while Jose State enjoys its first overall victory and UPenn tops the electric field. Taking action early to conquer the STEM crisis Interest in STEM subjects falls precipitously as students progress through elementary and middle school.
Uncertainty quantification The technique is a must for next-generation simulation tools. Oil-pump sizing Researchers from Hinduja Tech investigate options for low friction and power consumption. The future of Indian commercial aviation The growth in traffic that airport modernization has supported has also made a significant contribution to the local and national economies, while the improved infrastructure has been positive for the perception of India in the global market. Driving EVs toward lower cost The race ison to reduce battery and electric-drive systems cost while improving efficiency. Powering on Rolls-Royce's Chief Engineer discusses new technologies that inspire current R&D design and evaluation work as part of its strategic roadmap for future big commercial programs. HMIs extend beyond the cab Telematic functions are being integrated into multi-function user interfaces.
Toward smarter manufacturing and materials At the U.K.'s new Advanced Manufacturing Research Center, engineers and innovators have at their disposal some of the world's most advanced design and manufacturing assets for precision engineering. More electric, integrated fuel systems Engine system reliability can be improved by advanced electric architectures, while the reduction of hydraulic components, fuel tubes, and fittings can enhance the maintainability of the engine and minimize pilot workload.
Adaptive trimming of composite parts Some of the techniques used in the Adaptive Manufacturing System are normal aerospace processes. The unique and enabling process is the scanning and adaptive trimming.
3-D manufacturing of titanium components takes off MRO providers are discovering ways to innovate their procedures while remaining viable and profitable through the current downturn in government spending. Commercial programs are flying high With economic regeneration underway this year, the rate of ordering new aircraft has been at an all-time high, with the result that backlogs for undelivered new production stretch well into the next decade for some popular models.
Simulation helps manage change in aircraft manufacturing Commercial aircraft demand is up even while sequestration and other forces are forcing scale-backs in defense-related programs. From managing complex supply chains to improving scrap rates in casting, digital simulation is proving a valuable aid.
Propulsion Fanjet Evolution - the Next Steps Composites Dry Drilling Composites Using Carbon Dioxide Cooling
Wireless sensing--the road to future digital avionics A look at the comparative performance of wired and wireless sensors, type of wireless sensors & interfaces, frequency performance, protocols, network topologies and qualification standards. Testing reality in an increasingly complex design space Digital simulation tools have transformed the designing and testing of new airplanes, as well as the way they are manufactured and sustained.
Materials become design, design becoems function Once things you could hold in your hand, materials have become more design ideas than entities, and the designs themselves are transforming into operational activity. The next steps in flight A look at sero engine and assembly developments as commercial airframe and engine manufacturers begin the biggest battle of all-for next-generation short-haul jet aircraft sales. NextGen Today and tomorrow The FAA has reached a major milestone on the Next Generation Air Transportation System initiative to modernize America's National Airspace System. Stacking the material deck for the 787 Combinations such as composites and titanium being used in future aircraft programs can be very challenging when drilling holes during manufacturing and assembly operations.
A new model for University research The robotics team at Carnegie Mellon University innovates with a new approach for the funding and commercialization of University research. Automotive and Aerospace engineering education: today and tomorrow Student opportunites in specialized programs continue to grow. Lamborghini is bullish about new flagship Of all the models making their world debut at the 2011 Geneva Motor Show, Lamborghini's Aventador LP 700-4 could claim top honors for new technology. B-Max launches downsized EcoBoost engines The small B-Max MAV uses familiar Ford "kinetic" design cues. Diesel/electric-drive military vehicle at Chicago auto show A military vehicle is designed to perform specific missions, not serve as an environmental showcase.
Viewing 1 to 30 of 12825


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