Littérature scientifique sur le sujet « Post-manufacturing test »
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Sommaire
Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « Post-manufacturing test ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Articles de revues sur le sujet "Post-manufacturing test"
1
Akinuli, Bankole O., Akintan Akinyemi A., Adedayo Olawale C. et Adedotun Adewale K. « The Influence of Macroeconomic Variables on Manufacturing Sectors : A Case of Nigeria ». International Journal of Research and Innovation in Social Science VIII, IIIs (2024) : 22–42. http://dx.doi.org/10.47772/ijriss.2024.803003s.
Texte intégralRésumé :
This study has examined the influence of macroeconomic variables on manufacturing sectors with a particular reference to Nigerian economy. The objective of the study is to investigate the effects of macroeconomic variables on manufacturing sectors (proxy businesses, productivity sectors and industries) in Nigeria. Econometrics tools were employed to analyse the variables sourced from the Central Bank of Nigeria Statistical bulletin within the period of 1985 up to 2022. Among the pre-test conducted on the variables are unit root test, descriptive statistics and co-integration bound test. Meanwhile, post-diagnosis test conducted include: stability test, heteroskedacity test, and serial correlation test. The findings show that macroeconomic variables have mixed influences on the manufacturing sector in Nigeria. It is, therefore, recommended that the government should effectively stabilise and manage interest rate, exchange rate and inflation rate with a view of creating enabling environment for manufacturing firms and potential investors in Nigeria. The government should intensify the efforts of garnering more foreign earnings by harnessing international trades.
2
Visca, Eliseo, Emanuele Cacciotti, Anton Komarov, Stefano Libera, Nikolay Litunovsky, Alexey Makhankov, Andrea Mancini et al. « Manufacturing, testing and post-test examination of ITER divertor vertical target W small scale mock-ups ». Fusion Engineering and Design 86, no 9-11 (octobre 2011) : 1591–94. http://dx.doi.org/10.1016/j.fusengdes.2011.02.079.
Texte intégral
3
Wang, Zeyuan, et Yufeng Zhou. « Fatigue lifetime prediction of a 3D-printing dental implant by Finite Element Analysis ». MATEC Web of Conferences 232 (2018) : 02060. http://dx.doi.org/10.1051/matecconf/201823202060.
Texte intégralRésumé :
This study clarifies the differences between additive manufacturing and traditional manufacturing and the differences in product properties. The fatigue life of 3D printed dental implants was studied by finite element analysis. Pure titanium dental implant made by Concept laser3D printer in Germany is modelled by Solidworks 2016. Finite element analysis was performed in Ansys17.0 and the fatigue lifetime test is predicted in its post-processing system. These components are assembled by software Solidworks according to ISO14801. The maximum and minimum values of each index are obtained in the fatigue post process.
4
Mohammadi, Arefeh, Kevin Grosskopf et John Killingsworth. « An Experiential Online Training Approach for Underrepresented Engineering and Technology Students ». Education Sciences 10, no 3 (25 février 2020) : 46. http://dx.doi.org/10.3390/educsci10030046.
Texte intégralRésumé :
Workforce pipelines are essential to sustain a productive workforce in an increasingly competitive, high-tech environment. Advanced automation, sensors, materials and data analytics will increase the need for highly skilled workers in the manufacturing (and manufactured construction) sector. Attracting and developing the next-generation workforce is not without its challenges; however, students are often deficient in technical skills and generally have negative perceptions about manufacturing and construction. As a result, new education and training models have been developed to provide instruction at all levels of the educational system, with a focus on both traditional students and non-traditional students, including ethnic minorities, women, veterans, disabled persons and older adult learners. This study focused specifically on certain underrepresented students in STEM programs offered at community colleges in the Great Plains region of the U.S. An available online training program by the Society of Manufacturing Engineers was used as a contextualized online training tool. The Learning Management System embedded in this online training tool was used to gather student data. Conducting multiple regression analyses on the test outcomes, completion rates, and improvement between post-test and pre-test scores showed that female participants achieved greater improvement between pre- and post-test scores than males, and achieved higher rates of credentialing compared to all other demographic groups. African American participants achieved greatest improvement between pre- and post-test scores than all other ethnic groups while Hispanics achieved higher rates of module completion. Additionally, this study also examines the background related to contextualized teaching and learning, as well as the effectiveness of this delivery method for these underrepresented populations.
5
KIM, JUNG SU, DONG SOO KIM, MIN CHEOL LEE et WON HEE LEE. « A METHOD OF 3D FREEFORM FABRICATION USING A CURING OF PHOTOPOLYMER RESIN ». International Journal of Modern Physics B 22, no 09n11 (30 avril 2008) : 1839–45. http://dx.doi.org/10.1142/s021797920804750x.
Texte intégralRésumé :
Recently, Study of 3D freeform fabrication method was working in the various applications. For example, in the powder base, it's laminated using a binding method or laser sintering method. However, the demerits of these methods are to take long time for post process and not enough to keep high strength of manufacturing part. The binding method needs the post process and the time for post process needs longer time than a manufacturing time. The sintering method has huge size of system with module of the laser. In this paper, we introduce a method of 3D freeform fabrication using a curing of photopolymer resin. A photopolymer curing method has simply fabrication process and high strength of manufacturing part. So, we are configuration the system with compact type module for the office environment and experiment a UV curing test with photopolymer resin in the 3D freeform fabrication method. In the conclusion, we fabricate the 3D freeform part, which is suitable to the office environment using a photopolymer curing method.
6
Rohmat Hidayat, Agus, Nur Alifah et Medika Oga Laksana. « Financial Performance Analysis : Manufacturing Companies In Indonesia Before And Post The 2008 Global Economic Crisis ». Journal of Comprehensive Science (JCS) 1, no 5 (23 décembre 2022) : 1267–75. http://dx.doi.org/10.59188/jcs.v1i5.158.
Texte intégralRésumé :
This study aims to analyze the financial performance of Indonesian manufacturing companies before and after the global economic crisis in 2008. In this study, financial performance is measured by Return on Assets (ROA), Return on Equity (ROE), and Net Profit Margin (NPM). By comparing the average ROA, ROE, and NPM before and after the crisis, the results of the descriptive analysis were tested. It can be seen that ROA, ROE and NPM after the crisis were higher than before the crisis. As a result, post-crisis financial performance has improved compared to before the crisis. Based on the descriptive analysis, it is known that the financial performance of manufacturing companies after the crisis is better than before the crisis. Based on the t test, the results of ROA, ROE and NPM tests were obtained as follows. First, Post-crisis ROA is higher than before the 2008 global economic crisis, and the increase is said to be large. Second, post-crisis return on equity appears to be higher than before the global economic crisis, but this is not statistically significant. Third, post-crisis NPM also appears to be larger than before the crisis, but not statistically significant. The results of the t test show that financial performance as measured by ROA has improved after the crisis compared to before the crisis.
7
Eke, Ihuoma Chikulirim, Felix Awara Eke et Awara Emeng Edom. « Infrastructure and Manufacturing Sector Performance in Nigeria ». International Journal of Research and Scientific Innovation X, no VII (2023) : 130–39. http://dx.doi.org/10.51244/ijrsi.2023.10717.
Texte intégralRésumé :
The objective of this study was to investigate the effect of infrastructure (electricity consumption and paved roads) on manufacturing sector performance in Nigeria for the period 1981-2019. The ex post facto research design was adopted for the study, using a combination of the traditional Ordinary Least Squares (OLS) econometric method, and the Augmented Dickey-Fuller unit root test for robust and valid estimation results. The co-integration test showed that the equations in the model were integrated. The study findings revealed that infrastructure, proxy by electricity supply had an adverse but not significant effect on manufacturing sector performance while paved roads had a positive and significant impact on manufacturing performance in Nigeria. The study recommends a total overhaul of the electricity sub-sector and targets increased supply specifically for industrial consumption as well as exploring alternative options to increase the road network such as public-private partnership arrangements given its importance to industrial performance.
8
Pirozzi, Carmine, Stefania Franchitti, Rosario Borrelli, Antonio Chiariello et Luigi Di Palma. « The Effect of Post-Processing on the Mechanical Behavior of Ti6Al4V Manufactured by Electron Beam Powder Bed Fusion for General Aviation Primary Structural Applications ». Aerospace 7, no 6 (5 juin 2020) : 75. http://dx.doi.org/10.3390/aerospace7060075.
Texte intégralRésumé :
In this work a mechanical characterization of Ti6Al4V processed by electron beam powder bed fusion additive manufacturing was carried out to investigate the viability of this technology for the manufacturing of flyable parts for general aviation aircraft. Tests were performed on different manufacturing conditions in order to investigate the effect of post processing as machining on the mechanical behavior. The study provides useful information to airframe designers and manufacturing specialists that work with this technology. The investigation confirms the low process variability and provides data to be used in the design loop of general aviation primary structural elements. The test results show a high level of repeatability indicating that the process is well controlled and reliable enough to match the airworthiness requirements. In addition, the so-called “as-built specimens”, i.e., specimens produced by the electron beam melting machine without any major post-processing, have lower mechanical performances than specimens subjected to a machining phase after the electron beam melting process. Specific primary structural elements will be designed and flight cleared, resulting from the findings presented herein.
9
Muzindutsi, Paul-Francois. « Manufacturing Production and Non-Agricultural Employment rate in South Africa : Time Series Analysis ». Journal of Economics and Behavioral Studies 6, no 10 (30 octobre 2014) : 779–86. http://dx.doi.org/10.22610/jebs.v6i10.537.
Texte intégralRésumé :
South African is faced with a high unemployment rate; however, the country’s manufacturing sector is one of the sectors that have been linked with job creation. Nevertheless, the growth in manufacturing production may not increase employment opportunities if this sector continues to shift to technology-intensive methods of production, which displace labour. This study uses a vector autoregressive (VAR) model to estimate the interaction between manufacturing production and the employment rate in South Africa from 1970 to 2013. Results revealed that both variables were stationary at the first difference and there was a long-term equilibrium relationship between the variables. In the short term, a significant positive relationship between manufacturing production and employment rate was observed. Granger causality test showed that there is a causal link from manufacturing production to the employment rate. A comparison between apartheid and post-apartheid periods showed the long-run relationship only existed in the post-apartheid period of a more open economy. Findings of this study revealed that a growth in the South African manufacturing sector is linked with employment opportunities in the short-run. However, these opportunities may be reduced by changes in technology which promote capital intensive production. As such, policy-makers should encourage policies that promote a mix of labour and capital intensive production in order to maintain these employment opportunities in the manufacturing sector.
10
Onakoya, Adegbemi Babatunde. « Macroeconomic Dynamics and the Manufacturing Output in Nigeria ». Mediterranean Journal of Social Sciences 9, no 2 (1 mars 2018) : 43–54. http://dx.doi.org/10.2478/mjss-2018-0024.
Texte intégralRésumé :
AbstractThis paper examined the impact of the changes in the macroeconomic factors on the output of the manufacturing sector in Nigeria from 1981 to 2015. Preliminary evaluation of the data was conducted using both descriptive statistics and stationarity evaluation. The test indicated that not all the variables are normal. The occurrence of order integration at first level difference necessitated the deployment of the Johansen cointegration test. The findings revealed no short run association among manufacturing output and each of GDP, exchange rate, broad money supply and unemployment rate. Negative relationship existed amongst inflation rate, interest rate, exchange rate, broad money supply on one hand, and manufacturing output. The inflation rate and interest rate, were statistically insignificant. However, significant and positive relationship existed between GDP of the previous year and unemployment on the one hand and manufacturing output on the other, at 5 percent level. The results showed that manufacturing was a veritable engine of economic growth. The post estimation tests showed presence of serial correlation but evidence of heteroscedasticity existed which, made the model inefficient, but its estimator is still unbiased. The study recommended the harmonization of both fiscal and monetary policies for the attainment of macroeconomic stability and avoidance of rapid policy summersaults.
Thèses sur le sujet "Post-manufacturing test"
1
Pavlidis, Antonios. « Analog Hardware Fault Diagnosis ». Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS452.
Texte intégralRésumé :
Le nombre de circuits intégrés (CIs) utilisés dans les applications liées à des missions critiques et à la sûreté augmente sans cesse. Ces applications imposent aux CIs de présenter des propriétés de sûreté fonctionnelle. Cette thèse introduit un auto-test intégré (BIST) pour les CIs analogiques et à signaux mixtes, appelé autotest à symétrie (SymBIST) pour répondre à l’objectif de sûreté fonctionnelle. SymBIST repose sur le principe du BIST et sur l'existence de signaux invariants en fonctionnement nominal et variant en cas de fonctionnement erroné. Les invariants sont mesurés à l'aide de dispositifs intégrés spécifiques. SymBIST répond à trois objectifs de sûreté fonctionnelle : le test les défauts du CI, le test en ligne, et le diagnostic les défauts. SymBIST est démontré sur un convertisseur analogique-numérique à approximations successives (CAN SAR). Les résultats montent que la couverture de test et la précision de diagnostic sont plus élevées que l’état de l’artThe number of integrated circuits (ICs) used in safety- and mission-critical applications is ever increasing. These applications demand that ICs carry functional safety properties. In this thesis, we develop a Built-In Self Test (BIST) approach for Analog and Mixed-Signal (A/M-S) ICs, called Symmetry-Based Built-In Self Test (SymBIST), which achieves several objectives towards the functional safety goal. SymBIST is a generic BIST paradigm based on identifying inherent invariances that should hold true only in error-free operation, while their violation points to abnormal operation. The invariances are being checked using dedicated on-die checkers. SymBIST meets three functional safety objectives: post-manufacturing defect-oriented test, on-line testing, and fault diagnosis. SymBIST is demonstrated on a successive approximation analog-to-digital converter (SAR ADC). The results show that the test coverage and diagnostic accuracy are promising compared to the state of the art
2
Rocco, Nicola. « Additive Manufacturing e Medicina Rigenerativa per la Ricostruzione Mammaria Post-Mastectomia per Cancro della Mammella ». Tesi di dottorato, 2017. http://www.fedoa.unina.it/12021/1/Tesi%20Dott.%20Nicola%20Rocco.pdf.
Texte intégralRésumé :
Le pazienti sottoposte a mastectomia per cancro della mammella hanno oggi a disposizione numerose opzioni ricostruttive, che permettono di ottenere buoni livelli di soddisfazione da parte delle pazienti ed offrono una buona qualità della vita post-operatoria, aiutando a ristabilire la fiducia da parte della paziente nella propria immagine corporea. Tali tecniche ricostruttive non sono però esenti da complicanze che possono rendere necessari re-interventi e sono spesso associate a risultati poco stabili nel tempo.
Con lo scopo di ridurre le complicanze correlate con le attuali opzioni ricostruttive e migliorare la qualità della vita ed i livelli di soddisfazione delle donne sottoposte a mastectomia per cancro della mammella, proponiamo una nuova strategia ricostruttiva con l’utilizzo di scaffold “customizzati” prodotti con tecniche di stampa 3D e l’ausilio di tecniche di medicina rigenerativa con trapianto autologo di tessuto adiposo.
Grazie a tecniche di "reverse engineering", scaffold "cuciti su misura" saranno prodotti a partire da immagini di Tomografia Computerizzata o Risonanza Magnetica della mammella da ricostruire e saranno posizionati in sede sottocutanea a livello della sede della mastectomia conservativa. Lo scaffold tridimensionale sarà poi colonizzato con tessuto adiposo autologo in alcune sessioni. La struttura cucita su misura aiuterà a mantenere la forma della mammella ed il tessuto adiposo trapiantato fornirà la consistenza naturale della stessa.
Presentiamo i risultati delle analisi meccaniche sugli scaffold e i test biologici di vitalità e proliferazione cellulare delle cellule staminali di derivazione adiposa all'interno degli scaffold stessi. Tali analisi hanno reso possibile la realizzazione del nostro primo scaffold customizzato in policaprolattone.
Il prossimo step del progetto di ricerca consisterà nello studio su animali della biocompatibilità delle strutture messe a punto e la valutazione dell’interazione in vivo tra il tessuto adiposo e lo scaffold stesso.
Successivamente si proporrà uno studio clinico randomizzato e controllato che metterà a confronto l’attuale gold standard, ossia la ricostruzione con impianti protesici con la nostra proposta ricostruttiva in donne sottoposte a mastectomia conservativa per cancro della mammella in fase iniziale.
Chapitres de livres sur le sujet "Post-manufacturing test"
1
Pessina, Domenico, Davide Facchinetti, Francesco Santoro, Pierluigi Febo, Santo Orlando, Danilo Monarca, Massimo Cecchini et al. « Design, Manufacturing, and Strength Test of a 4-post ROPS Fitted on a Very Low-Profile Tractor (TRACLAS Project) ». Dans Lecture Notes in Civil Engineering, 468–76. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-98092-4_48.
Texte intégral
2
de la Torre, Héctor García, Ariadna Chueca de Bruijn, Giovanni Gómez-Gras et Marco A. Pérez. « Influence of Ball Burnishing on the Improvement of Surface Quality and Mechanical Performance of Parts Obtained by FFF ». Dans Proceedings of the XV Ibero-American Congress of Mechanical Engineering, 327–33. Cham : Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-38563-6_48.
Texte intégralRésumé :
AbstractAdditive manufacturing parts often need post-treatment due to inherent shortcomings, such as poor surface quality or mechanical performance. Ball burnishing, a plastic deformation technique, can reduce these drawbacks. In this research, a specific tool was designed, and statistical models were used to determine optimal process parameters. Flexural and fatigue tests were conducted to assess the effects of ball burnishing on surface and dimensional quality, hardness, and mechanical behavior. The study shows that ball burnishing can benefit cast filament parts made of three materials and provides generalizations for its application. This research represents a novel contribution to using ball burnishing and highlights its advantages.
3
Stolt, Roland, et Anders E. W. Jarfors. « Manufacturing of High Pressure Die Casting Die Inserts Using SLM ». Dans Advances in Transdisciplinary Engineering. IOS Press, 2020. http://dx.doi.org/10.3233/atde200206.
Texte intégralRésumé :
Dies for high pressure die casting are normally manufactured by machining of slabs of tool steel to the required dimensions. This manufacturing requires several steps such as rough machining, heat-treatment, EDM (electro discharge machining) and polishing. With the AM (additive manufacturing) method SLM (Selective Laser Melting) it has become possible to print the dies fully or in part. Several advantages are expected, such as a better thermal distribution in the die in service and thereby extended die life and better component quality. This is due to the possibility of making the cooling channels conformal. There are also expectations of reduced time and cost in the manufacturing process due to fewer manufacturing steps and better material utilisation. Hopes are to print a net shape or near net shape that can be used directly as a die component. In this paper it is investigated to what extent this can be fulfilled by printing two die inserts to be used for casting fatigue test samples of aluminium. They were printed on a 3D Systems ProX DMP 300 in maraging steel powder. The result is that it is possible to obtain a sufficiently smooth surface die surface. However, the current design with an SLM insert fitted in a machined die makes extensive post printing manufacturing necessary.
4
« Post‚ÄìHydrostatic Test Cleaning ». Dans Practical Guide to Pressure Vessel Manufacturing. CRC Press, 2002. http://dx.doi.org/10.1201/9780203908433.ch9.
Texte intégral
5
Heinzman, Joseph Robert. « Sociotechnical Systems and Work Approaches ». Dans Business Models to Promote Technology, Culture, and Leadership in Post-COVID-19 Organizations, 1–27. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-4358-3.ch001.
Texte intégralRésumé :
Sociotechnical systems theory is important because it brings together technology, behavioral culture, and leadership as it applies in the business environment. To understand where we may be going, it's important to review how past sociotechnical systems have been approached and how those systems were affected by work through scientific management, quality improvement, technological advancements, behavioral focus, and economics. Trust and collaboration are hallmarks of leadership, most agree managers manage things (task) and leaders lead (guide and support) people. COVID-19 has caused challenges to managing and leading, a disruption in our supply chain, manufacturing to adjust, and management to be more focused on innovation and sociotechnical systems in the United States. Manufacturing is a key indicator of employment and jobs health, and the current job loss in industry has been accelerated. Going forward, different skills, education, and industry focus will test innovation and the balance between management of things and leadership of people.
Actes de conférences sur le sujet "Post-manufacturing test"
1
Ahmed, Soyed Tuhin, et Mehdi B. Tahoori. « Fault-tolerant Neuromorphic Computing with Functional ATPG for Post-manufacturing Re-calibration ». Dans 2022 IEEE 40th VLSI Test Symposium (VTS). IEEE, 2022. http://dx.doi.org/10.1109/vts52500.2021.9794185.
Texte intégral
2
Datta, Rudrajit, et Nur A. Touba. « Post-manufacturing ECC customization based on Orthogonal Latin Square codes and its application to ultra-low power caches ». Dans 2010 IEEE International Test Conference (ITC). IEEE, 2010. http://dx.doi.org/10.1109/test.2010.5699221.
Texte intégral
3
Eberl, Brandon, Christopher Mikolanis, K. Eberl, C. McKeel, E. Ketusky et T. Krentz. « Effects of Post-Manufacturing Process on Material Properties of 3D Printed Vessels ». Dans ASME 2020 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/pvp2020-21785.
Texte intégralRésumé :
Abstract With the advancing capabilities for fabricating metal components using Additive Manufacturing (AM) (3D-Printing), designers are looking for ways to utilize the AM capabilities in new applications. A potential application for AM is the fabrication of pressure-retaining components or fittings with complex geometries that are difficult to fabricate using traditional methods (e.g., machining and welding). Using AM parts for pressure-retaining components presents new challenges to ensure the material will perform reliably and predictably to meet the specifications of the design. This paper summarizes work performed on 316L stainless steel vessels fabricated by AM. The AM vessels were evaluated before and after Hot Isostatic Pressing (HIP) post-processing, including destructive examination to evaluate the grain structure and strength. Tensile tests on baseline samples and samples subjected to HIP were compared to a test sample machined from conventional stainless material and leak tests were performed on an AM vessel using helium as a tracer gas. The role of the HIP post-processing is to reduce the metal porosity and other defects inherent in the 3D-metal printing process. HIP post-processing allows the finished product to achieve the strength, reliability and leak tightness requirements of national consensus standards, such as the American Society of Mechanical Engineers Boiler and Pressure Vessel Code.
4
Cheng, Hang Shawn, Jian Cao et Hui-Ping Wang. « Experimental and Numerical Analysis of the Buckling and Post-Buckling Phenomenon in the Yoshida Test ». Dans ASME 2006 International Manufacturing Science and Engineering Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/msec2006-21029.
Texte intégralRésumé :
Simulation-based Design and Manufacturing has shown its great effectiveness in shortening the design cycle. The objective of this work was to further increase the robustness of numerical prediction in capturing subtle wrinkling in sheet metal forming process. A stress-based wrinkling predictor is further developed to predict the initiation and wave mode of potential wrinkling in forming of flat sheet. The predictor is linked to the LS-DYNA commercial FEM package. Stress prediction from LS-DYNA was compared to the implicit code ABAQUS and satisfactory results were obtained. Hence, stress, nodal coordinates and connectivity information of the LS-DYNA simulation are fed into the predictor via an automatic interface program. A set of Yoshida buckling tests was used as a verification tool for the wrinkling predictor. 0.78mm thick 180B steel and 1.012mm thick 6111-T4P aluminum are tested. Through the comparison of the experiments and simulations, it shows that the wrinkling predictor is able to predict the initiation point and wave mode for the wrinkling accurately. In addition, post-buckling behavior in numerical simulations was captured through including initial imperfections following the wrinkling mode predicted. It was found that such a method provides more reliable results in terms of the post-buckling behavior than random imperfection.
5
Sinn, Thomas, et Ron Barrett. « Design, Manufacturing and Test of a High Lift Secondary Flight Control Surface With SMAPBP (Shape Memory Alloy Post-Buckled Precompressed) Actuators ». Dans ASME 2010 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2010. http://dx.doi.org/10.1115/smasis2010-3681.
Texte intégralRésumé :
This paper discusses the design, manufacturing and test of a new kind of adaptive airfoil with Shape Memory Alloy actuation. An antagonistic arrangement of SMA wires is used in a Post-buckled Precompressed (PBP) kind of actuator that is being employed in an adaptive flap system. SMA actuators are typically used either antagonistically and/or arranged to move structural components with linearly varying resistance levels, like springs. This generally means that large percentages of strain energy are spent doing work on passive structure (rather than performing the task at hand, like moving a flight control surface or resisting air loads etc.). Post-Buckled Precompressed (PBP) actuators on the other hand are arranged so that the active elements do not waste energy fighting passive structural stiffnesses. Most (if not all) of the PBP actuators of the past have used piezoceramic elements and are highly prone to tensile failure on convex faces. Because SMA actuators are far more tolerant of tensile stresses than piezoceramics, a switch of actuator type is a natural progression of technology. With the Post-buckled Precompressed mechanism, the power consumption to hold deflections is reduced by one if not two orders of magnitude. Because aircraft often require flight control surfaces to be held in a given position for extremely long times to trim the vehicle, conventional SMA’s are essentially non-starters for many classes of aircraft. For the reason that PBP actuators balance out air and structural loads, the steady-state load on the SMAs is essentially negligible, when properly designed. Experiments showed that the SMAPBP actuator shows tip rotations on the order of 45° which is nearly triple the levels achieved by piezoelectric PBP actuators. The paper opens with a short survey on the history of flap systems actuated by adaptive materials and delves into actuation theory. In the following the author gives a detailed explanation of the design concept and the manufacturing of the airfoil. A NACA0012 airfoil with a chord length of 150 mm was used to prove the concept of the adaptive flap system. The paper continues with a description of the test setup, the CFD model assumptions and the results of wind tunnel tests. The architecture and the employment of a closed loop position feedback system to overcome the nonlinear behavior of the SMA material and the PBP mechanism is also discussed.
6
Jacobsen, Karina, Michael Carolan et Patricia Llana. « Test Requirements of Locomotive Fuel Tank Blunt Impact Tests ». Dans ASME 2013 Rail Transportation Division Fall Technical Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/rtdf2013-4701.
Texte intégralRésumé :
The Federal Railroad Administration’s Office of Research and Development is conducting research into passenger locomotive fuel tank crashworthiness. A series of impact tests are planned to measure fuel tank deformation under two types of dynamic loading conditions. This paper describes the test requirements for the preliminary tests in this series — a blunt impact of conventional locomotive fuel tanks. Current design practice requires that Tier 1 locomotive fuel tanks have minimum properties adequate to sustain a prescribed set of static load conditions [1]. In accidents, fuel tanks are subjected to dynamic loading, often including a blunt or raking impact from various components of the rolling stock or trackbed. Current research is intended to increase understanding of the impact response of fuel tanks under dynamic loading. Utilizing an approach that has been effective in increasing the structural crashworthiness of passenger railcars, improved strategies can be developed that will address the types of loading conditions which have been observed to occur in a collision or derailment event. The improvement strategies developed by this research program can then be applied to alternative fuel tank designs, such as diesel multiple unit (DMU) tanks. This paper describes test requirements for conducting two preliminary tests. These tests are referred to as preliminary because they will be used to evaluate the loading setup and instrumentation planned for the larger series of tests. These preliminary tests will evaluate a blunt impact on the bottom surface of two conventional passenger locomotive fuel tanks. The test articles chosen for the preliminary tests are fuel tanks removed from two retired EMD F-40 locomotives. While these fuel tanks do not reflect the current state of locomotive fuel tank manufacturing or design, they are suitable for means of these tests. Each fuel tank will be mounted to a crash wall and impacted on its bottom face by an impact cart with a rigid impactor at a prescribed velocity. The first set of tests is designed to measure the deformation behavior of the fuel tanks. These tests are planned to result in puncture of the bottom surface of each fuel tank. The preliminary tests are targeted for October 2013 at the Transportation Technology Center (TTC) in Pueblo, Colorado. Following this first series of impact tests, a second set of dynamic impact tests is planned to be conducted. This second set will include both blunt and raking impact conditions on conventional fuel tanks, DMU fuel tanks and fuel tanks incorporating improved strategies for impact protection. Lessons learned during the preliminary two tests will be applied during the second set of tests to improve the performance of those tests. Fuel tank research is being performed to determine strategies for increasing the fuel tank impact resistance to mitigate the threat of a post-collision or post-derailment fire.
7
Klinger, Alexander, et Brian A. Weiss. « Robotic Work Cell Test Bed to Support Measurement Science for Monitoring, Diagnostics, and Prognostics ». Dans ASME 2018 13th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/msec2018-6617.
Texte intégralRésumé :
Industrial robotics users, integrators, and manufacturers are implementing advanced monitoring, diagnostics, and prognostics (collectively known as Prognostics and Health Management (PHM)) techniques and technologies. PHM can take many different forms when implemented, and measures of effectiveness are highly dependent on the techniques implemented. A test bed has been built, and a use case designed, to represent common manufacturing tasks performed in robot work cells where PHM can provide greater equipment and process health intelligence. The physical and functional relationships within the work cell are mapped using a hierarchical deconstruction method to gain a better understanding of the propagation of effects of both equipment and process degradation. The test bed has been built so PHM techniques and technologies can be integrated and tested in a realistic scenario. Data is recorded for post processing and analysis for the verification and validation (V&V) of the implemented PHM techniques. The test bed will serve as a platform to develop, test, verify, and validate PHM techniques at the National Institute of Standards and Technology (NIST), and provide industry participants a standard platform for testing their PHM technologies. Having a common testing platform will provide industry a foundation for sets of tests to evaluate PHM. This paper presents the test bed and use case, the relationships therein, and the data management and collection approaches used to enable future research.
8
Xu, Lijuan, Qiang Huang, Arman Sabbaghi et Tirthankar Dasgupta. « Shape Deviation Modeling for Dimensional Quality Control in Additive Manufacturing ». Dans ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-66329.
Texte intégralRésumé :
Dimensional quality control is critical for wider adoption of Additive Manufacturing (AM) as a direct manufacturing technology. Due to the process’ complex physics, AM-fabricated parts still require post-processing with machine tools, which significantly negates its time and cost benefits. In this paper, we investigate product shape deviation for Mask Image Projection Stereolithography (MIP-SLA) — one of the earliest commercialized AM techniques. By studying part fabrication mechanisms, we consider (i) over or under exposure, (ii) light blurring and (iii) phase change induced shrinkage or expansion as the most significant sources for shape deviations. Accordingly, the shape deviation modeling is established to quantify the effects of those influential factors and to understand the deviation mechanisms. Cylinders and cubes of various sizes were built to test our approach. Accurate prediction of shape deviation for all parts serves as a further confirmation of our model.
9
Rogers, Benedict A., Max D. A. Valentine, Elise C. Pegg, Alexander J. G. Lunt et Vimal Dhokia. « Additive Manufacturing of Star Structured Auxetic Lattices With Overhanging Links ». Dans 2022 International Additive Manufacturing Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/iam2022-93965.
Texte intégralRésumé :
Abstract Additive manufacturing has been the driving force behind the growth of metamaterials as a field. Commonly taking the form of lattices, these structures can achieve a range of novel macroscale properties that stem from the cumulative effects of locally designed mechanisms. A wide array of mechanical metamaterials have already been designed using computational methods, but these rarely undergo physical testing, often as a result of manufacturing difficulties. This work approaches the problem of manufacturing complex metamaterial test samples though a case study of 3D petal-based auxetic star lattices. These lattice structures have linkage structures with overhanging elements, which is a common feature in metamaterial concepts but challenging to print. Trials of the test samples were manufactured using a thermoplastic polyurethane filament combined with polyvinyl acetate support at 20, 30 and 40 mm unit cell sizes. It was found that the main geometric challenges for successful printing were the link thickness and the reliability of the prints. To address unreliability, the geometry was cut into layers of cells with adhesive-connected feet and printed in parts for post-process assembly. The layered approach was tested successfully and was estimated to reduce the number of cells needed to be attempted to print the full lattice by over 80%. The use of dissolvable support material proved viable for printing overhanging links, but requires use of fused deposition modelling so a relatively low part resolution. The trial led to a five point design guide methodology for metamaterial test samples. Combined with cell mathematical definitions that strictly bound link thickness to take minimum print resolution into account, this methodology can be applied to other metamaterials and help bridge the gap between theoretical lattices and physical testing.
10
Marnot, Alexandra, Jaehyun Cho et Blair Brettmann. « Print Speed Optimization for UV-Assisted 3D Printing of Lunar Regolith Simulants Composite Inks ». Dans ASME 2023 18th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/msec2023-102275.
Texte intégralRésumé :
Abstract Direct-ink-write (DIW) 3D printing of dense composite inks is an attractive method of additive manufacturing for Lunar missions using in-situ derived resources. DIW offers a wide degree of freedom for formulation design with multiple methods for solidifying the inks post-extrusion. The use of UV-curing, however, poses certain complications when the loading of particles in the ink reaches levels above 50 vol% due to light scattering, absorption, and reflection. Herein, we investigate the curability of two Lunar regolith simulants, compared against a model system of glass microspheres, as particles in UV-curable inks. Photo-DSC is utilized to assess the degree of cure of the inks at a range of timescales. These results are tied to depth of cure experiments following the ISO 4049 method to verify cure depths meeting a target print layer height and to optimize the speed of printing while maintaining structural integrity. The extent of cure is verified both qualitatively through print shape fidelity and quantitatively through ATR-FTIR. This work not only highlights the importance of particle mineralogy for achievable UV-assisted solidification post-extrusion, but also presents test methods easily adapted to a design of experiment framework that require very little sample volume to identify successful formulations and printing parameters.
Rapports d'organisations sur le sujet "Post-manufacturing test"
1
Benavente, José Miguel, et Pluvia Zuñiga. The Effectiveness of Innovation Policy and the Moderating Role of Market Competition : Evidence from Latin American Firms. Inter-American Development Bank, septembre 2021. http://dx.doi.org/10.18235/0003655.
Texte intégralRésumé :
This paper evaluates whether market competition matters for the effectiveness of innovation policies. Using data for manufacturing firms in Chile and Peru, we implement propensity matching techniques combined with differences-in-differences estimation to evaluate the impact of innovation subsidies on the post-treatment innovation investment effort of firms and test whether such impact differs according to the intensity of competition. We corroborate the existence of crowding-in effects in beneficiaries when compared to a control group of untreated firms. The subsidy impact is found either only significant in highly competitive sectors or larger in more competition-intensive industries -compared to low competition ones. Thus, we confirm that market competition plays a moderating role in the effectiveness of innovation policies to stimulate firm innovation investment. The results are robust to different matching and estimation methods and suggest, therefore, the importance of considering market contexts in the design of innovation policies.