Academic literature on the topic 'Equivalent Material Model'
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Journal articles on the topic "Equivalent Material Model"
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Jeon, Chi-Ho, Jae-Bin Lee, Sokanya Lon, and Chang-Su Shim. "Equivalent material model of corroded prestressing steel strand." Journal of Materials Research and Technology 8, no. 2 (April 2019): 2450–60. http://dx.doi.org/10.1016/j.jmrt.2019.02.010.
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Alamayrekh, Yekaterina Yu. "Model of the decryption and model of the abbreviation formal diversity in the abbreviation group “auto-”." Current Issues in Philology and Pedagogical Linguistics, no. 2(2020) (June 25, 2020): 91–102. http://dx.doi.org/10.29025/2079-6021-2020-2-91-102.
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The article deals with the principles of the analyses of the formal structure of the equivalence in the families of the equivalence of the compound abbreviations by the example of the abbreviation group “auto”. The relevance of the research is determined by the fact that on the basis of the synchronic equivalent approach to the description of the compound abbreviations a new interpretation of the characteristics of the formal equivalence of the word and correlated word-combination is described systematically. The results of this study provide a means of predicting the equivalence relations for the adjacent abbreviation clusters that is important while composing the techniques of making the dictionaries of a new type – explanatory dictionaries of abbreviations, the distinctive feature of which is the presentation of all equivalent word-combinations detected in the texts. The material for the study is formed by 252 families of equivalence which form the abbreviation group “auto” and contains 1621 abbreviation doubles: “compound abbreviation” – “equivalent word-combination”. The research was carried out on the basis of descriptive and quantitative methods as well as descriptive analyses and formalization. The author defines such notions as “compound abbreviation”, “decryption inducement”, “family of equivalence” as the basic categories of the synchronic approach to the abbreviation. The methods of synchronic analysis of the formal equivalence devised in the Laboratory are described: the analyses technique of the decryption inducement that designates the structural peculiarities of the decryption inducement – the stereotype of the decryption of compound abbreviation, and the analyses technique of the formal diversity of the equivalency that is a detached scheme of the combination of the components of the equivalent word-combination in the abbreviation. While development of the models of the decryption inducements the part of speech characteristics of the words forming the decryption inducements and their order in the equivalent word-combination are taken into account. While designing the models of formal equivalence that include the model of the equivalent word collocations and the abbreviation model, the correlation of the constructs of the correlated units, their peculiar grammatical features and the representation status in in words and word collocations are designated
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CAI, Lailiang, Kan WU, Qisheng YU, and Jinpeng FENG. "A New Method of Equivalent Material Model Deformation Observation." International Journal of Modern Education and Computer Science 3, no. 5 (August 1, 2011): 40–46. http://dx.doi.org/10.5815/ijmecs.2011.05.06.
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Guo, Hongwei, Chuang Shi, Meng Li, Zongquan Deng, and Rongqiang Liu. "Design and Dynamic Equivalent Modeling of Double-Layer Hoop Deployable Antenna." International Journal of Aerospace Engineering 2018 (2018): 1–15. http://dx.doi.org/10.1155/2018/2941981.
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This study proposes deployable units driven by elastic hinges and a double-layer hoop deployable antenna composed of these units. A rational modeling method based on the energy equivalence principle is presented to develop an equivalent model of the double-layer hoop antenna in accordance with the structural characteristics of the antenna. The equivalent beam models of the rods with elastic hinges are proposed. The relationship of geometrical and material parameters is established considering the strain energy and the kinetic energy of the periodic unit, which are the same as those of the equivalent beam in the same displacement field. The equivalent model of the antenna is obtained by assembling several equivalent beam models in the circumferential direction. The precision of the equivalent model of the antenna is acceptable as found by comparing the modal analysis results obtained through equivalent model calculation, finite element simulation, and modal test.
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Gyimóthy, Szabolcs. "Modeling stationary moving medium by static magneto-electric material." European Physical Journal Applied Physics 85, no. 1 (January 2019): 10901. http://dx.doi.org/10.1051/epjap/2018180161.
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The electromagnetic equivalence of a stationary moving medium to magneto-electric materials is studied. The equivalent material characteristics of the medium at rest is obtained in terms of the diffusion tensor coefficient of the governing partial differential equation. Special attention is paid to the transition condition of field quantities on the boundary of the moving medium; it is found that the nonmoving magneto-electric equivalent model must be supplied with surface sources. The method is demonstrated through examples and verified by finite element simulation.
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Fan, Pengxian, Haozhe Xing, Linjian Ma, Kaifeng Jiang, Mingyang Wang, Zechen Yan, and Xiang Fang. "Bulk Density Adjustment of Resin-Based Equivalent Material for Geomechanical Model Test." Advances in Materials Science and Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/363869.
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An equivalent material is of significance to the simulation of prototype rock in geomechanical model test. Researchers attempt to ensure that the bulk density of equivalent material is equal to that of prototype rock. In this work, barite sand was used to increase the bulk density of a resin-based equivalent material. The variation law of the bulk density was revealed in the simulation of a prototype rock of a different bulk density. Over 300 specimens were made for uniaxial compression test. Test results indicated that the substitution of quartz sand by barite sand had no apparent influence on the uniaxial compressive strength and elastic modulus of the specimens but can increase the bulk density, according to the proportional coarse aggregate content. An ideal linearity was found in the relationship between the barite sand substitution ratio and the bulk density. The relationship between the bulk density and the usage of coarse aggregate and barite sand was also presented. The test results provided an insight into the bulk density adjustment of resin-based equivalent materials.
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Zanelli, L., A. Montanaro, E. L. Carniel, P. G. Pavan, and A. N. Natali. "The study of equivalent material parameters in a hyperelastic model." International Journal of Non-Linear Mechanics 89 (March 2017): 142–50. http://dx.doi.org/10.1016/j.ijnonlinmec.2016.12.014.
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Garala, Thejesh Kumar, Ge Cui, Naman Kantesaria, Charles M. Heron, Alec M. Marshall, and Lukáš Žižka. "Characterisation of spoil materials to develop an equivalent spoil material for physical model tests." Górnictwo Odkrywkowe LXIII, no. 4 (October 4, 2022): 23–29. http://dx.doi.org/10.5604/01.3001.0053.8055.
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The engineering behaviour of spoil (overburden) needs to be explored either to understand the stability of reservoir slopes under various geological and climatic conditions or for the effective utilisation of reclaimed mines for sustainable infrastructure (e.g., onshore wind turbines). The spoil material is usually considered as highly heterogeneous, and samples collected from the same site can exhibit widely varying characteristics. In this study, spoil material from a mine site in the Czech Republic is characterised using in-situ field tests and laboratory tests. Cone penetration tests were performed in the field and sample cores were collected for laboratory testing. In the laboratory, the index and engineering characteristics of the spoil were evaluated. Given the measured characteristics and behaviour of the field spoil, an equivalent spoil is proposed to perform physical modelling tests using geotechnical centrifuge. This enables simulation of the field spoil behaviour in controlled centrifuge testing, from which other aspects of spoil (e.g. stability of spoil slopes, spoil-structure interaction) can be investigated.
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Won Kim, Jae, Jae Ung Cho, Chan Ki Cho, and Jin Oh Kim. "A study on damage to mechanical seat cushion made from different materials of extension frame." International Journal of Engineering & Technology 7, no. 3.3 (June 8, 2018): 315. http://dx.doi.org/10.14419/ijet.v7i2.33.14176.
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Background/Objectives: : Automotive seat is a very important component to prevent accidents by reducing passenger’s tiredness, thus, this study worked on analyzing damage with different materials of extension frames of mechanical seat cushions.Methods/Statistical analysis: In this study, we performed an experiment on cushion extension frames by splitting it into two parts. We studied about the damage prediction of slave body for each material property of ABS, PP, PLA, and PA6.6. For analyzing the condition, we assigned the side part of the master body for fixed support, and we progressed on analysis by applying with 690N on the entire part of the slave body.Findings: This research worked on the study of damage to different materials of extension frames of seat cushions. After confirming the stress equivalence of the entire model for each material, PP showed the highest equivalent stress of 180.88MPa, and ABS showed the lowest equivalent stress of 151.73MPa. Overall, we could see that in the order of ABS, PA6.6, PLA, PP have a higher tendency to be broken. In addition, when confirming equivalent stress of master body depending on materials of slave body, PA6.6 showed the highest equivalent stress of 166.3MPa, and ABS showed the lowest equivalent stress of 124.06MPa. Overall, we could see that in the order of ABS, PP, PLA and PP6.6 have a higher tendency to be broken. In comparing shear stress on the gear part, which has the highest tendency to be broken in among the entire model, depending on the material of the slave body, PLA showed the greatest shear stress of 88.945MPa, and ABS showed the lowest shear stress of 69.766MPa.Improvements/Applications: This study worked for the improvements and applications of cushion extension frames as the securement of material by investigating these factors.
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Xian, Xiang Ping, Yan Shuai Wang, Feng Xing, and Bi Qin Dong. "Measuring and Modeling Analysis of Electrochemical Impedance Spectroscopy for Hydration Procedure of Cement Materials." Advanced Materials Research 588-589 (November 2012): 1033–36. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.1033.
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In this paper, the electrochemical impedance spectroscopy method is applied to characteristic the hydration procedure in cement materials. And a new equivalent circuit model is developed to express the hydration procedure of cement material. As cement paste is a complicated electrochemical system with multi-phase transmission, the equivalent circuit model is considered with the additional double layer capacitance effect at the interface among the hydration products in cement materials. It can express the electrochemical station in cement material, as the multi-phase mass transmission in the cement-based material during the hydration procedure.
Dissertations / Theses on the topic "Equivalent Material Model"
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Al-wattar, Tahseen Abdulridha Ali. "Developing equivalent solid model for lattice cell structure using numerical approaches." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1610335304435815.
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Aydincak, Ilke. "Investigation Of Design And Analyses Principles Of Honeycomb Structures." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608998/index.pdf.
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In this thesis, design and analyses of honeycomb structures are investigated. Primary goal is to develop an equivalent orthotropic material model that is a good substitute for the actual honeycomb core. By replacing the actual honeycomb structure with the orthotropic model, during the finite element analyses, substantial advantages can be obtained with regard to ease of modeling and model modification, solution time and hardware resources . To figure out the best equivalent model among the approximate analytical models that can be found in the literature, a comparison is made. First sandwich beams with four different honeycomb cores are modeled in detail and these are accepted as reference models. Then a set of equivalent models with the same dimensions is generated. The material properties of the equivalent models are taken from different studies performed in the literature. Both models are analyzed under the same loading and the boundary conditions. In finite element analyses, ANSYS finite element program is used. The results are compared to find out the best performing equivalent model. After three major analyses loops, decision on the equivalent model is made. The differences between the total reaction forces calculated by the equivalent model and the actual honeycomb model are all found to be within 10%. The equivalent model gives stress results at the macro-scale, and the local stresses and the strains can not be determined. Therefore it is deemed that for stress analysis, equivalent model can be used during the preliminary design phase. However, the equivalent model can be used reliably for deflection analysis, modal analysis, stiffness determination and aero-elastic analysis.
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Eriksson, Anna. "Carbon dioxide and Energy flows in Jämtland’s waste sector." Thesis, Mittuniversitetet, Avdelningen för ekoteknik och hållbart byggande, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-29087.
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The aim of this study is to assess the current situation of energy and carbon flows through the waste sector in Jämtland. An energy flow analysis is performed by balancing the inflows and outflows of the lower heating value and embodied energy. A carbon flow analysis was made on the same principles although with the carbon content and embodied CO2eq. The results are showing that over a period of one year, 75 000 tons of waste flows through the waste sector in Jämtland. Approximately 60 % of all the waste is incinerated. The energy analysis shows that 970TJ flows through the waste sector every year. Household waste is the category with most energy consumption and emissions in total. However, other materials like metal and electronics have higher energy and carbon content per ton than the household category. The results of the analyses can further be implemented in the Sustainable Jämtland model and it can then be used as a base when making strategies for a sustainable waste treatment.
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Guy, Philippe. "Contribution à l’étude et à la caractérisation des propriétés mécaniques de structures lattices métalliques obtenues par Fabrication Additive (fusion sur lit de poudre)." Electronic Thesis or Diss., Toulouse, ISAE, 2025. http://www.theses.fr/2025ESAE0005.
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La fabrication additive s’est beaucoup développée ces dernières années dans l’industrie, notamment dans le secteur spatial. Cette technologie permet de concevoir et de fabriquer des pièces de géométrie complexe souvent impossible à obtenir par les procédés conventionnels. C’est le cas en particulier des structures lattices qui restent à ce jour difficiles à dimensionner et qui sont encore délicates à maîtriser en matière de stabilité de fabrication.Cette thèse avait pour objectifs d'améliorer la compréhension et la prédiction du comportement mécanique des structures lattices, structures qui sont de plus en plus présentes dans les satellites. Des éprouvettes sandwiches avec âme lattice de type BCC ou Dode-Thin (DT) ont été mises à disposition par Thales Alenia Space – France. Ces éprouvettes en aluminium AS7G06 ou en titane TA6V ont été fabriquées par fusion laser sur lit de poudre. De nombreux essais statiques et dynamiques ont été réalisés ainsi que différents calculs prédictifs analytiques et numériques.Les propriétés mécaniques équivalentes de cellules parfaites sans défauts ont été déterminées par Éléments Finis (EF) et ont été comparées à la théorie des poutres. Un modèle théorique de la poutre DT a été particulièrement développé permettant de modéliser par EF les cellules DT comme un ensemble d’éléments poutres 1D ou un matériau homogénéisé équivalent. Les essais mécaniques ont permis de mesurer la rigidité des éprouvettes sandwiches. Des mesures complémentaires par microscopie optique, MEB et microtomographie RX ont permis de mesurer la géométrie réelle des sections des poutres.Les rigidités mesurées sont le plus souvent inférieures à celles prédites par calculs. Les écarts observés sont dus aux imperfections géométriques des poutres réellement fabriquées, à la présence de porosités internes et aussi au fait que les matériaux imprimés ont des propriétés moindres que celles des matériaux de fonderie, notamment des modules de Young plus faibles. Un outil informatique de post-traitement des images de la tomographie a été développé pour quantifier les différences de rigidité et de masse et les comparer aux valeurs nominales. Les modèles mis à jour suite à ces observations ont conduit à une nette amélioration de la corrélation entre essais et calculs.À l’issue de ces travaux, les ingénieurs et les chercheurs bénéficient maintenant de méthodes et de formules permettant de modéliser simplement des structures BCC et Dode-Thin. Grâce aux nombreuses mesures et observations expérimentales, ces travaux ont aussi contribué à une meilleure compréhension du comportement des structures lattices.D’autres axes de recherche peuvent être envisagés pour continuer à développer et à améliorer leur dimensionnement. Il faudrait continuer à étudier l’influence de la non rectitude des fibres moyennes et du désalignement des nœuds d’intersection. Il serait aussi intéressant de réaliser des mesures et essais supplémentaires pour observer la qualité de fabrication actuelle. Le développement d’outils informatiques de traitement des images de tomographie RX rend possible la création de modèles EF 3D représentatifs de la géométrie réelle des poutres fabriquées et aussi la construction à terme de jumeaux numériques en s’appuyant sur l’intelligence artificielleAdditive manufacturing technology has created new possibilities in design for aerospace components, particularly using lattice structures. The industrial challenge remains to size these structures within a reasonable lead time.This research aimed to improve the understanding and prediction of the mechanical performance of lattice structures that are increasingly used in spacecraft components.Thales Alenia Space – France provided lattice core sandwich beams manufactured by the powder bed laser beam melting process. The mechanical properties of two types of cell, BCC and Dode-Thin, were investigated for two metal alloys, AS7G06 aluminium and TA6V titanium. We performed a number of static and vibration tests and predicted the mechanical behaviour of the specimens using both analytical and numerical calculations.Various Finite Element (FE) models were developed to calculate the effective mechanical properties of a defect-free structure and compared with the beam theory. In particular, we established a theory of cross-sectional properties for the specific Dode-Thin strut. This allowed the Dode-Thin lattice cell to be modelled as a set of 1D beam elements or an equivalent 3D-orthotropic homogenised material. Tests were also carried out to measure the stiffness of the sandwich beams. Optical and SEM observations and X-ray computed tomography (CT) determined the actual cross-sectional properties of the struts.The experiments in this study generally showed that theoretical and numerical predictions significantly overestimated the stiffnesses. Porosity rate and geometrical imperfections were the main causes of the discrepancy between the prediction and the as-built parts. In addition, the 3D-printed materials exhibited a lower Young’s modulus. An in-house code was developed to calculate the cross-sectional properties directly from the CT data and compare them with the nominal properties. These observations and results helped to explain the differences in stiffness and mass and were used to update the predictive models, resulting in a better correlation with the experimental results for static and dynamic behaviour.Finally, this study provided the engineer with a simple method for replacing BCC and Dode-Thin cells with equivalent beams of solid circular cross-section, or with homogenised mechanical properties. This study also deepened the knowledge of the as-built lattice structures and their mechanical behaviour.Further research should explore the effect of strut waviness and the misalignment of the junction centres. Additional tests with other samples manufactured more recently and benefiting from developments in the SLM technique could be conducted. The in-house code we have started to develop for post-processing digital CT images could be enhanced with new functions. We could envisage the construction of a full FE tetrahedral volumetric mesh capturing the geometric imperfections of each strut. This could make it possible to identify the true effective stiffness of the strut geometry. This approach could pave the way for the creation of a digital twin consisting of a FE lattice model constructed directly from CT data
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Lago, Nicolò. "Characterization and modelling of organic devices for simultaneous stimulation and recording of cellular electrical activity with Reference-Less Electrolyte-Gated Organic Field-Effect Transistors." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3426781.
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The study of neuronal and neurodegenerative diseases requires the development of new tools and technologies to create functional neuroelectronics allowing both stimulation and recording of cellular electrical activity. In the last decade organic electronics is digging its way in the field of bioelectronics and researchers started to develop neural interfaces based on organic semiconductors. The interest in such technologies arise from the intrinsic properties of organic materials such as low cost, transparency, softness and flexibility, as well the biocompatibility and the suitability in realizing all organic printed systems. In particular, organic field-effect transistor (OFET) -based biosensors integrate the sensing and signal amplification in a single device, paving the way to new implantable neural interfaces for in vivo applications.
To master the sensing and amplification properties of the OFET-based sensors, it is mandatory to gain an intimate knowledge of the single transistors (without any analytes or cells) that cannot be limited to basic characterizations or to general models. Moreover, organic transistors are characterized by different working principles and properties as respect to their inorganic counterpart. We performed pulsed and transient characterization on different OFETs (both p-type and n-type) showing that, even though the transistors can switch on and off very fast, the accumulation and/or the depletion of the conductive channel continues for times as long as ten seconds. Such phenomenon must be carefully considered in the realization of a biosensor and in its applications, since the DC operative point of the device can drift during the recording of the cellular signals, thus altering the collected data. We further investigate such phenomenon by performing characterizations at different temperatures and by applying the deep level transient spectroscopy technique. We showed that the slow channel accumulation (and depletion) is due to the semiconductor density-of-states that must be occupied in order to bring the Fermi energy level close to the conduction band. This is a phenomenon that can takes several seconds and we described it by introducing a time-depend mobility. We also proposed a technique to estimate the behavior, in time, of the position of the Fermi energy level as respect to the conduction band.
To understand the electrochemical transduction processes between living cell and organic biosensor, we realized two-electrodes structure (STACKs) where a drop of saline solution is put directly in contact with the organic semiconductor. On these devices, we performed electrochemical impedance spectroscopy at different DC polarizations and we developed an equivalent circuit model for the metal-organic semiconductor-solution structures that are typically used as transducers in biosensor devices. Our approach was extending the standard range of the bias voltages applied for devices that operate in water. This particular characterization protocol allowed to distinguish and investigate the different mechanisms that occur at the different layers and interfaces: adsorption of ions in the semiconductor; accumulation and charge exchange of carriers at the semiconductor/electrolyte interface; percolation of the ionic species through the organic semiconductor; ion diffusion across the electrolyte; ion adsorption and charge exchange at the platinum interface. We highlighted the presence of ion percolation through the organic semiconductor layer, which is described in the equivalent circuit model by means of a de Levie impedance. The presence of percolation has been demonstrated by environmental scanning electron microscopy and profilometry analysis. Although percolation is much more evident at high negative bias values, it is still present even at low bias conditions. In addition, we analyze two case studies of devices featuring NaCl (concentration of 0.1M) and MilliQ water as solution, showing that both cases can be considered as a particular case of the general model presented in this manuscript.
The very good agreement between the model and the experimental data makes the model a valid tool for studying the transducing mechanisms between organic films and the physiological environment. Hence this model could be a useful tool not only for the characterization and failure analysis of electronic devices, such as water-gated transistors, electrophysiological interfaces, fuel cells, and others electrochemical systems, but also this model might be used in other applications, in which a solution is in intimate contact with another material to determine and quantify, if undesired mechanisms such as percolation and/or redox corrosive processes occur.
Lastly, the knowledge gain on OFETs and STACKs were put together to realize electrolyte-gated field effect transistors (EGOFETs). We then developed a model to describes EGOFETs as neural interfaces. We showed that our model can be successfully applied to understand the behaviour of a more general class of devices, including both organic and inorganic transistors. We introduced the reference-less (RL-) EGOFET and we showed that it might be successfully used as a low cost and flexible neural interface for extracellular recording in vivo without the need of a reference electrode, making the implant less invasive and easier to use. The working principle underlying RL-EGOFETs involves self-polarization and back-gate stimulation, which we show experimentally to be feasible by means of a custom low-voltage high-speed acquisition board that was designed to emulate a real-time neuron response. Our results open the door to using and optimizing EGOFETs and RL-EGOFETs for neural interfaces.Lo studio delle malattie neuronali e neuro-degenerative richiede lo sviluppo di nuovi strumenti e tecnologie per creare dispositivi neuro-elettronici funzionali che consentano sia la stimolazione che la registrazione dell'attività elettrica cellulare. Nell'ultimo decennio l'elettronica organica sta emergendo nel campo della bioelettronica e diversi gruppi di ricerca hanno iniziato a sviluppare interfacce neurali basate su semiconduttori organici. L'interesse per tali tecnologie deriva dalle proprietà intrinseche dei materiali organici quali basso costo, trasparenza, morbidezza e flessibilità, nonché la biocompatibilità e l'idoneità nella realizzazione di sistemi stampati completamente organici. In particolare, i biosensori basati sulla tecnologia a transistor ad effetto campo organico (OFET) integrano il sensing e l'amplificazione del segnale in un singolo dispositivo, aprendo la strada a nuove interfacce neurali impiantabili per applicazioni in vivo. Per padroneggiare le proprietà di rilevamento e amplificazione dei sensori basati su OFET, è obbligatorio acquisire una conoscenza approfondita dei singoli transistor (senza la presenza di analiti e/o cellule) che vadano oltre le caratterizzazioni di base o modelli generali. Inoltre, i transistor organici sono caratterizzati da diversi principi di funzionamento e diverse proprietà rispetto alla loro controparte inorganica. In questo lavoro abbiamo svolto caratterizzazioni impulsate e transienti su diversi OFET (sia di tipo p che di tipo n) mostrando che, anche se i transistor possono accendersi e spegnersi molto velocemente, l'accumulo e/o lo svuotamento del canale conduttivo continua per tempi che possono superare le decine di secondi. Tale fenomeno deve essere attentamente considerato nella realizzazione di un biosensore e nelle sue applicazioni, poiché il punto operativo DC del dispositivo può andare alla deriva durante la registrazione dei segnali cellulari, alterando così i dati raccolti. Questo fenomeno viene ulteriormente approfondito caratterizzano i dispositivi a diverse temperature e per mezzo della tecnica DLTS. Abbiamo dimostrato che il lento accumulo (e svuotamento) del canale è dovuto alla densità di stati del semiconduttore organico che devono poter essere occupati per portare il livello energetico di Fermi vicino alla banda di conduzione. Questo è un fenomeno che può richiedere diversi secondi che possiamo descrivere introducendo una mobilità dipendente dal tempo. Per comprendere i processi di trasduzione elettrochimica tra cellule viventi ed il biosensore organico, abbiamo realizzato una struttura a due elettrodi (STACK) in cui una goccia di soluzione salina viene messa direttamente a contatto con il semiconduttore organico. Su questi dispositivi, abbiamo eseguito la spettroscopia di impedenza elettrochimica a diverse polarizzazioni DC e abbiamo sviluppato un modello circuitale equivalente per le strutture metallo/semiconduttore organico/soluzione che vengono tipicamente utilizzate per la realizzazione di bio-trasduttori. Il nostro approccio prevede di estendere il range standard delle tensioni operative per questo genere di dispositivi. Ciò ha permesso di investigare e distinguere i diversi fenomeni che si verificano nei diversi strati e interfacce: adsorbimento di ioni nel semiconduttore; accumulo e scambio di cariche di portanti all'interfaccia semiconduttore/elettrolita; percolazione delle specie ioniche attraverso il semiconduttore organico; diffusione di ioni attraverso l'elettrolita; adsorbimento di ioni e scambio di carica all'interfaccia col metallo. Abbiamo evidenziato la presenza di percolazione ionica attraverso lo strato di semiconduttore organico, che è descritto nel modello circuitale per mezzo di un'impedenza di de Levie. La presenza di percolazione è stata dimostrata mediante microscopia elettronica a scansione ambientale e analisi profilometrica. Sebbene la percolazione sia molto più evidente a valori di bias negativi elevati, risulta presente anche a basse condizioni di bias. L'ottimo accordo tra il modello e i dati sperimentali rende il modello un valido strumento per studiare i meccanismi di trasduzione tra film organici e l'ambiente fisiologico. Quindi questo modello può essere uno strumento utile non solo per la caratterizzazione e l'analisi dei guasti dei dispositivi elettronici, come water-gated transistor, interfacce elettrofisiologiche, celle a combustibile e altri sistemi elettrochimici, ma anche nel caso in cui una soluzione è in intimo contatto con un altro materiale per determinare e/o quantificare se si verificano meccanismi indesiderati come percolazione e/o processi corrosivi. Infine, il bagaglio di conoscenze ottenuto studiando i dispositivi OFET e STACK è stato messo utillizato per realizzare dispositivi EGOFET. Abbiamo quindi sviluppato un modello per descrivere gli EGOFET come interfacce neurali. Abbiamo dimostrato che il nostro modello può essere applicato con successo per comprendere il comportamento di una classe più generale di dispositivi, compresi i transistor sia organici che inorganici. Abbiamo introdotto l'RL-EGOFET (reference-less EGOFET) e abbiamo dimostrato che questa struttura può essere utilizzata con successo come interfaccia neurale flessibile per il recording extracellulare in vivo senza la necessità di un elettrodo di riferimento, rendendo l'impianto meno invasivo e più facile da usare. I nostri risultati aprono la strada all'utilizzo e all'ottimizzazione di EGOFET e RL-EGOFET come interfacce neurali.
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Riesco, Refoyo Javier. "Development of battery models for on-board health estimation in hybrid vehicles." Thesis, KTH, Materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211680.
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Following the positive reception of electric and hybrid transport solutions in the market, manufacturers keep developing their vehicles further, while facing previously undertaken challenges. Knowing the way lithium-ion batteries behave is still one of the key factors for hybrid electric vehicles (HEVs) development, especially for the requirements of the battery management system during their operation. Hence, this project focuses on the necessity of robust yet reasonably simple and cost-effective models of the battery for estimating the health status during the operation of the vehicles. With this aim, the procedure and models to calculate the state-of-health (SOH) indicators, internal resistance and capacity, are proposed and the results discussed. Two machine-learning based models are presented, a support vector machine (SVM) and a neural network (NN), together with one equivalent circuit model (ECM). The data used for training and validating the models comes from testing the batteries in the laboratory with standard performance tests and real driving cycles along the battery lifespan. However, data sets measured in actual heavy-duty vehicles during their operation for three years is also analysed and compared. With respect to this matter, a study of the battery materials, behaviour and operation attributes is carried out, highlighting the main aspects and issues that affect the development of the models. The inputs for the models are signals that can be measured on-board in the vehicles, as current, voltage or temperature, and other derived from them as the state-of-charge (SOC) calculated by the internal battery management unit. Time-series of the variables are used for simulation purposes. The management of signals and implementation of the models is done in the environment of Matlab-Simulink, using some of its in-built functions and other specifically developed. The models are evaluated and compared by means of the normalized root mean squared error (NRMSE) of the voltage output profile compared to that of the tested batteries, but also the error of the internal resistance calculations calculated from the voltage profile for the three models, and the internal parameters in case of the ECM. While despite the difficulties faced with the data, the models can eventually perform accurate estimations of the resistance, the results of the capacity estimations are omitted in the document due to the lack of useful information derived. Nevertheless, the calculation procedure and other considerations to take into account regarding the capacity estimation and data sets are undertaken. Finally, the conclusions about the data used, battery materials and methods evaluated are drawn, laying down recommendations as to design the performance tests following the conditions of the driving cycles, and indicating the higher general performance of the SVM respect the other two methods, while asserting the usefulness of the ECM. Moreover, the battery with NMC material composition is observed to be easier to predict by the models than LFP, also showing different evolution of its internal resistance.
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Giljum, Stefan, Hanspeter Wieland, Franz Stephan Lutter, Nina Eisenmenger, Heinz Schandl, and Anne Owen. "The impacts of data deviations between MRIO models on material footprints: A comparison of EXIOBASE, Eora, and ICIO." Wiley, 2019. http://dx.doi.org/10.1111/jiec.12833.
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In various international policy processes such as the UN Sustainable Development Goals, an urgent demand for robust consumption-based indicators of material flows, or material footprints (MFs), has emerged over the past years. Yet, MFs for national economies diverge when calculated with different Global Multiregional Input-Output (GMRIO) databases, constituting a significant barrier to a broad policy uptake of these indicators. The objective of this paper is to quantify the impact of data deviations between GMRIO databases on the resulting MF. We use two methods, structural decomposition analysis and structural production layer decomposition, and apply them for a pairwise assessment of three GMRIO databases, EXIOBASE, Eora, and the OECD Inter-Country Input-Output (ICIO) database, using an identical set of material extensions. Although all three GMRIO databases accord for the directionality of footprint results, that is, whether a countries' final demand depends on net imports of raw materials from abroad or is a net exporter, they sometimes show significant differences in level and composition of material flows. Decomposing the effects from the Leontief matrices (economic structures), we observe that a few sectors at the very first stages of the supply chain, that is, raw material extraction and basic processing, explain 60% of the total deviations stemming from the technology matrices. We conclude that further development of methods to align results from GMRIOs, in particular for material-intensive sectors and supply chains, should be an important research priority. This will be vital to strengthen the uptake of demand-based material flow indicators in the resource policy context.
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VENEZIANI, GLAUCO R. "Desenvolvimento de um objeto simulador "Canis Morphic" utilizando impressora 3D para aplicação em dosimetria na área de radioterapia veterinária." reponame:Repositório Institucional do IPEN, 2017. http://repositorio.ipen.br:8080/xmlui/handle/123456789/27967.
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O aumento na longevidade humana fez surgir uma série de doenças com a idade; em contrapartida o avanço da medicina possibilitou o diagnóstico precoce e o tratamento de várias doenças antes incuráveis. Esse cenário atual estendese também aos animais domésticos (cães e gatos - PETs) que dobraram sua expectativa de vida nas últimas décadas, fato que os humanos demoraram séculos para alcançar. Do mesmo modo que os humanos, esse aumento na longevidade dos animais veio acompanhado de doenças relacionadas com a idade, entre elas o câncer. Uma das terapias utilizadas atualmente no tratamento do câncer é a radioterapia, técnica que utiliza a radiação ionizante para destruir as células tumorais (volume-alvo) com mínimo prejuízo aos tecidos circunvizinhos sadios (órgãos de risco). Essa técnica exige a realização periódica de testes de controle de qualidade, incluindo a dosimetria com a utilização de objetos simuladores equivalentes ao tecido, de modo a verificar a dose de radiação recebida pelo paciente em tratamento e compará-la posteriormente com a dose de radiação calculada pelo sistema de planejamento. A rápida expansão do mercado de impressoras 3D abriu caminho para uma revolução na área da saúde. Atualmente os objetos simuladores por impressão 3D estão sendo usados em planejamentos de Radioterapia para a localização espacial e mapeamento das curvas de isodose, realizando, assim, um planejamento mais personalizado para cada campo de radiação, além da confecção de implantes dentais, customização de próteses e confecção de bólus. Diante do exposto esse trabalho projetou e desenvolveu um objeto simulador chamado de \"Canis Morphic\" utilizando uma impressora 3D e materiais tecido-equivalentes para a realização dos testes de controle de qualidade e otimização das doses na área de Radioterapia em animais (cães). Os resultados obtidos demonstraram-se promissores na área de criação de simuladores por impressão 3D, com materiais de baixo custo, para aplicação no controle de qualidade em Radioterapia veterinária.
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
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Ouedraogo, Boureima. "Modélisation du rayonnement acoustique dans les guides traités par des matériaux absorbants à réaction localisée ou non localisée en présence d'écoulement par la méthode des éléments finis." Phd thesis, Université de Bourgogne, 2011. http://tel.archives-ouvertes.fr/tel-00674031.
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On s'intéresse dans ce travail au problème de propagation acoustique dans des guides à parois traitées avec des matériaux absorbants à réaction localisée ou non localisée en présence d'écoulement. En effet, dans les systèmes industriels comme les turboréacteurs d'avions, les silencieux d'échappement et les systèmes de ventilation, le bruit est le plus souvent canalisé vers l'extérieur par des guides de géométries plus ou moins complexes. Une étude des guides d'ondes permet donc de prédire et de comprendre les phénomènes physiques tels que la réfraction, la convection, l'absorption et l'atténuation des ondes. Dans l'étude des guides d'ondes, on considère souvent qu'ils sont infiniment longs afin de s'affranchir de certains phénomènes (réflexion par exemple) à leurs extrémités. Résoudre le problème de propagation dans les guides infinis par la méthode des éléments finis nécessite de tronquer le domaine infini par des frontières artificielles sur lesquelles des conditions limites transparentes doivent être écrites. Dans ce travail, les conditions limites transparentes sont écrites sous forme d'un opérateur Dirichlet-to-Neumann (DtN) basé sur une décomposition de la pression acoustique sur la base des modes propres du guide étudié tout en prenant en compte l'influence des paramètres comme l'écoulement et le traitement acoustique avec des matériaux absorbants. La propagation acoustique dans le guide est régie par un modèle scalaire basé sur l'équation de Helmholtz et les matériaux absorbants utilisés sont des matériaux absorbants d'impédance locale Z et des matériaux poreux. Nous nous sommes intéressés en particulier aux matériaux poreux ? squelette rigide que l'on modélise par un fluide équivalent car la propagation acoustique dans ces matériaux est aussi gouvernée par l'équation de Helmholtz comme dans un milieu fluide. Des résultats d'étude de la propagation acoustique dans des guides rectilignes uniformes traités en présence d'un écoulement uniforme ont permis de valider la méthode développée pour tronquer les domaines infinis. L'étude a aussi été menée avec succés pour des guides non uniformes traités en présence d'un écoulement potentiel.
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Sjödin, Mattias. "Investigating Particle Cracking in Single- and Polycrystalline Nickel-Rich Cathodes using In Situ Impedance Spectroscopy." Thesis, Uppsala universitet, Strukturkemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-449968.
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State-of-the-art Li-ion cathode materials are based on LiMO2 (M=Ni, Mn, Co) layered transition metal oxides (denoted NMC) with Ni-rich composition because of their high specific capacity. Yet, these materials suffer from poor capacity retention due to crack formation during de-/lithiation cycling. Particle cracking leads to exposure of new electrode surface which leads to Li-inventory loss, increased side reactions, and electric disconnection. Quantification of the extent of cracking is therefore desirable, especially during in situ whilst cycling of the Li-ion cell. Herein, we evaluate and improve an analytical methodology based on electrochemical impedance spectroscopy (EIS) in order to estimate the changes in electrochemically active surface area of both poly- and single-crystalline Ni0.8Mn0.1Co0.1(NMC811) active materials. A transmission-line model (TLM) applied to both non-blocking and blocking electrode condition was utilized in order to deconvolute and interpret the acquired experimental data. Fits of the complex TLM equivalent-circuits to the impedance spectra was facilitated by developing a global stochastic iterative function based on local multivariate optimization. Impedance analysis during short- term cycling showed that the single-crystalline NMC811 suffered from less particle cracking and side reactions compared to polycrystalline NMC811, which was also confirmed from post-mortem gas adsorption analysis. A novel approach to estimate the extent of particle cracking in commercial Li-ion cells by utilizing an empirically strong positive correlation between the charge-transfer capacitance and resistance was proposed. The work presented herein demonstrates the unique prospects of the EIS methodology in the development and research of future rechargeable batteries
Books on the topic "Equivalent Material Model"
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Pershina, K. D., and K. O. Kazdobin. Impedance spectroscopy of electrolytic materials. V.I. Vernadsky Institute of General and Inorganic Chemistry, 2012. http://dx.doi.org/10.33609/guide.2012.224.
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Electrochemical impedance spectroscopy (EIS) is playing an increasingly significant role in fundamental and applied research: to study any type of solid and liquid materials (ionic, mixed, semiconductor, and insulators), to study charge transfer in heterogeneous systems, including phase boundaries, electrode boundaries, and elements of the microstructure. With the help of EIS, it is possible to study the behavior of chemical sensors, fuel cells, batteries, and corrosion processes. The base of the method stays on the principle of exciting any electrochemical system with a signal in the form of a sinusoidal wave and observing its behavior in response to this disturbance. This is the simplest method for determining the structural and transport functions of the system under study. This is the simplest method for determining the structural and transport functions of the system under study. The book discusses the theoretical foundations of the method of impedance spectroscopy, including the method of equivalent circuits, and provides examples of the analysis of impedance spectra for real objects. The main attention is paid to the model elements of equivalent circuits, their physical base, and the use of the models in the analysis of electrochemical systems. Handbook consists of seven chapters. It has questions and tasks to self-work after each part. It is intended for students of chemical, chemical-technological, and biomedical specialties, as well as for specialists engaged in research in the field of materials science, medicine, and ecology.
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Bažant, Zdenek P., Jia-Liang Le, and Marco Salviato. Quasibrittle Fracture Mechanics and Size Effect. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780192846242.001.0001.
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Many modern engineering structures are composed of brittle heterogenous (a.k.a. quasibrittle) materials. These materials include concrete (an archetype), composites, tough ceramics, rocks, cold asphalt mixtures, and many brittle materials at the microscale. Understanding the failure behavior of these materials is of paramount importance for improving the resilience and sustainability of various engineering structures including civil infrastructure, aircraft, ships, military armors, and microelectronic devices. This book provides a comprehensive treatment of quasibrittle fracture mechanics. It first presents a concise but rigorous and complete treatment of the linear elastic fracture mechanics, which is the foundation of all fracture mechanics. The topics covered include energy balance analysis of fracture, analysis of near-tip field and stress intensity factors, Irwin's relationship, J-integral, calculation of compliance function and deflection, and analysis of interfacial crack. Built upon the content of linear elastic fracture mechanics, the book presents various fundamental concepts of nonlinear fracture mechanics, which include estimation of inelastic zone size, cohesive crack model, equivalent linear elastic fracture mechanics model, R-curve, and crack band model. The book also discusses some more advanced concepts such as the effects of the triaxial stress state in the fracture process zone, nonlocal continuum models, and discrete computational model. The significant part of the book is devoted to the discussion of the energetic and statistical size effects, which is a salient feature of quasibrittle fracture. The book also presents probabilistic fracture mechanics, and its consequent reliability-based structural analysis and design of quasibrittle structures. Finally, the book provides an extensive review of various practical applications of quasibrittle fracture mechanics.
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Henderson, Andrea. Analogy. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198809982.003.0005.
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Analogy was a crucial conceptual tool for Victorian natural philosophers, who regarded the physical world less in terms of material bodies than formal relationships. Thus, even as they aimed for verisimilitude in their theoretical models, James Clerk Maxwell and Michael Faraday used analogical figures freely, for they understood nature itself to be structured around analogical relations. Like Maxwell, Algernon Charles Swinburne wrote an undergraduate essay on the subject of analogy, conceiving it as fundamental to both scientific advancement and poetic production, where its logic of equivalence subsumes not only metaphor but also rhythm and rhyme. Swinburne’s poems “Before the Mirror” and “Sapphics” dramatize the replacement of the traditional notion of metaphor by the structures of formal analogy.
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Violi, Alessandra, Barbara Grespi, Andrea Pinotti, and Pietro Conte, eds. Bodies of Stone in the Media, Visual Culture and the Arts. Amsterdam University Press B.V., 2020. http://dx.doi.org/10.5040/9789048561582.
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If mediatization has surprisingly revealed the secret life of inert matter and the ‘face of things’, the flipside of this has been the petrification of living organisms, an invasion of stone bodies in a state of suspended animation. Within a contemporary imaginary pervaded by new forms of animism, the paradigm of death looms large in many areas of artistic experimentation, pushing the modern body towards mineral modes of being which revive ancient myths of flesh-made-stone and the issue of the monument. Scholars in media, visual culture and the arts propose studies of bodies of stone, from actors simulating statues to the transmutation of the filmic body into a fossil; from the real treatment of the cadaver as a mineral living object to the rediscovery of materials such as wax; from the quest for a ‘thermal’ equivalence between stone and flesh to the transformation of the biomedical body into a living monument.
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Durham, Alan L. Patent Law Essentials. 2nd ed. Praeger Publishers, 2004. http://dx.doi.org/10.5040/9798216194569.
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Business has always been driven by ingenuity and innovation. Now, more than ever, with an economy built on knowledge work and intangible value, developing—and protecting—intellectual property is vital for individuals and organizations alike. This book presents a brief but thorough survey of U.S. patent law, presented in the clearest possible terms for nonspecialists—including scientists, engineers, business managers, and entrepreneurs—as well as students and practitioners of patent and intellectual property law. Drawing from both practical and academic experience, Alan Durham explains the basis of patent law and covers such topics as the application process, claim interpretation, the requirements of novelty and non-obviousness, disclosure requirements (such as enablement and best mode), and infringement—including infringement under the controversial doctrine of equivalents. Complex legal issues are explained through in-depth examples, many borrowed from actual cases, and feature such timely topics as patent protection of computer software, business methods, and biological materials. This revised and updated edition discusses recent developments in the law and draws from the most current case authority. Used as an introduction to the topic or a handy desk reference, this book will be an indispensable guide to the dynamics and mechanics of patent law. Durham illustrates complex legal issues through dozens of in-depth examples, many borrowed from actual cases. Of particular interest are cases involving patent disputes over computer software, business practices, and biological materials. From building a better mousetrap to building a better mouse,Patent Law Essentialsdefines the coverage and limitations of patent law and its protections, and shows how they are applied in the courts and in practical application. This revised and updated edition discusses recent developments in the law and draws from the most current case authority. Used as an introduction to the topic or a handy desk reference, this book will be an indispensable guide to the dynamics and mechanics of patent law.
Book chapters on the topic "Equivalent Material Model"
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Sankrityayan, Rohit, Anoop Chawla, Sudipto Mukherjee, and Devendra K. Dubey. "Numerical Modeling of a Ceramic Honeycomb Using an Equivalent Material Model." In Lecture Notes in Mechanical Engineering, 233–40. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-3651-5_22.
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Rodríguez-Méndez, Francisco, Bruno Chiné, and Marcela Meneses-Guzmán. "Thermo-mechanical Stress Modeling of La(Fe,Co,Si)13 Thin Films Deposited on Porous Structures." In Proceedings of the XV Ibero-American Congress of Mechanical Engineering, 84–90. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-38563-6_13.
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AbstractThe thermo-mechanical behavior of a La(Fe,Co,Si)13 thin film deposited on a porous aluminum structure with a uniform geometry has been studied. Computational simulation techniques have been applied to the magnetocaloric material to model the thin film as a material with visco-plastic properties for thermal cycling at room temperature. The values obtained for stress, equivalent strain and cycles necessary for the material failure show a significant improvement in the mechanical stability and fatigue resistance of the metallic porous structure with the La(Fe,Co,Si)13 thin film, when compared to a model with the same geometry, but made entirely of La(Fe,Co,Si)13. These encouraging results prove the potential that this approach may have in the design and manufacture of magnetocaloric materials for magnetic refrigeration applications.
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Wu, Song, Ming Zhang, and Yunbo Zhou. "Study on Blast Resistance of Armored Steel Welded Joint Structures." In Lecture Notes in Mechanical Engineering, 865–76. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-1876-4_68.
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AbstractIn order to study the anti-detonation performance of welded joint structure of armored steel, the finite element analysis of welded joint structure under explosion impact was carried out by using material assignment method and structured ALE algorithm (S-ALE), and the accuracy of the model was verified by explosion impact test. The central deformation and failure form of each weld structure under different equivalent loads of a single explosion are studied. Repeated explosive loading of weld structure based on complete restart technology; The cumulative analysis of plastic deformation of weld structure under multiple explosions is realized, and the relationship between central deformation and explosion times and explosion equivalent is obtained.
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Gupta, K. K., D. P. Singh, T. N. Singh, and B. Singh. "Prediction of stability of haul roads over old underground workings through equivalent material model studies." In Off-Highway Haulage in Surface Mines, 255–65. London: Routledge, 2022. http://dx.doi.org/10.1201/9780203745090-38.
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Hussain, Mazhar, Mohd Kaleem Khan, and Manabendra Pathak. "Modelling of Phase Change Material Embedded Li-Ion Battery Pack Under Different Load Conditions Using Equivalent Circuit Model." In Lecture Notes in Mechanical Engineering, 373–85. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-7827-4_30.
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Heuts, Gijs, and Ieke Moerdijk. "Simplicial Operads and ∞-Operads." In Simplicial and Dendroidal Homotopy Theory, 555–90. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-10447-3_14.
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AbstractIn this final chapter we fulfil one of the main promises of this book, namely we prove that the homotopy theory of ∞-operads is equivalent to that of simplicial (or topological) operads. To prepare for this, Sections 14.1 and 14.2 establish some rather classical material on the homotopy theory of simplicial categories, most of it going back to the work of Dwyer and Kan. Then in Section 14.3 we establish a model structure on the category of simplicial operads in which the weak equivalences are the fully faithful and essentially surjective maps (in an appropriate interpretation of those terms).
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Sun, Chen, Minghua Dai, Liang Ying, Kai Du, Zhigang Chen, and Ping Hu. "Experimental and Numerical Simulation on Formability and Failure Behavior of Thermoplastic Carbon Fiber/AL Composite Laminates." In Lecture Notes in Mechanical Engineering, 383–93. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-58006-2_30.
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AbstractCarbon fiber reinforced thermoplastic/aluminum alloy (CFRTP/AL) composite laminates have the advantages of low density, high specific strength, and good fatigue resistance, which is a new type of engineering composite material to realize lightweight vehicle body. Heterogeneous interface delamination failure occurs in the forming process of the fiber metal laminates (FMLs). It is necessary to establish an effective finite element simulation strategy to accurately predict the delamination failure behavior of FMLs. In this work, thermoplastic PA6 continuous carbon fiber/AL FMLs were taken as the research object, and the double cantilever beam (DCB) and the end-notched flexure (ENF) experiments were carried out to determine the basic mechanical parameters between the interlayer interfaces of CFRTP/AL. Furthermore, a numerical simulation model based on ABAQUS software was developed to describe the progressive damage failure behavior of the CRFTP/AL in the forming process by using the equivalent modeling strategy of discontinuous micro-shear, which realized the effective prediction of ply directional damage failure of FMLs on the basis of the S-beam model. The results show that the established damage constitutive model and numerical method coupled with cohesive zone model (CZM) can effectively predict the ply directional damage failure behavior of CFRTP/AL composites during the large deformation forming.
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Mikhasev, Gennadi I., and Holm Altenbach. "Equivalent Single Layer Model for Thin Laminated Cylindrical Shells." In Advanced Structured Materials, 29–84. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-12761-9_2.
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Janiczek, Tomasz, Dorota Nowak-Woźny, Witold Mielcarek, and Krystyna Prociów. "Equivalent Model of Modified Bismuth Oxides Described by Fractional Derivatives." In Key Engineering Materials, 676–79. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-410-3.676.
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Guo, Rongjiao, and Renjun Yan. "Prediction of Mechanical Properties and Analysis of Damage Evolution of Fiber Bundles in Carbon Fiber Reinforced Composite Materials." In Lecture Notes in Mechanical Engineering, 633–46. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-1876-4_50.
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AbstractFiber bundles are an important component of woven composite materials, and predicting the mechanical properties of fiber bundles can provide a basis for the study of the mechanical properties of woven composite materials. This paper establishes the micro representative volume element (RVE) model of composite materials, and obtains the equivalent elastic constant of yarn through the model homogenization theory and periodic boundary conditions. Strength prediction is performed through the VUMAT user subroutine of ABAQUS. This paper uses the maximum stress standards and Von Mises standards to predict the damage initiation of TC33 carbon fiber and epoxy resin matrix, respectively. Combined with the constant degradation method, the simulation of the damage behaviors of the micro model is achieved, and the equivalent strength of the fiber bundle is obtained. The effectiveness and correctness of this method are verified by comparing the numerical model results with the Chamis theoretical model results. The accurate prediction of mechanical properties and damage process of fiber bundles provides theoretical support for the analysis of mechanical properties of composites, and has guiding significance for the performance design of composite materials.
Conference papers on the topic "Equivalent Material Model"
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Li, Yu-Qian, Jia-Yu Wu, Hao-Wei Gu, Zong-Yong Chen, Xiao-Bing Shi, and Hong Yuan. "An Equivalent Model of Corrugated Structures." In 2nd Annual International Conference on Advanced Material Engineering (AME 2016). Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/ame-16.2016.75.
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Nouir-Masmoudi, Haifa, and Nabila Dhahbi-Megriche. "Stress Grading Material Evaluation Using Equivalent Electric Network Model." In 2020 4th International Conference on Advanced Systems and Emergent Technologies (IC_ASET). IEEE, 2020. http://dx.doi.org/10.1109/ic_aset49463.2020.9318303.
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Cai, Lailiang, Kan Wu, Gang Hao, and Yanan Xu. "Notice of Retraction: Deformation Monitoring Study of Equivalent Material Model." In 2010 2nd International Conference on Information Engineering and Computer Science (ICIECS). IEEE, 2010. http://dx.doi.org/10.1109/iciecs.2010.5677715.
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Wei Zhang, Jianying Li, Guangwei Yang, Rui Xu, and Feng Liu. "Equivalent circuit model for cross-shaped frequency selective surface absorbing material." In 12th European Conference on Antennas and Propagation (EuCAP 2018). Institution of Engineering and Technology, 2018. http://dx.doi.org/10.1049/cp.2018.0515.
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Zhang, Jun. "Equivalent Laminated Model of the Aluminum Honeycomb Sandwich Panel." In 2015 International Conference on Material Science and Applications (icmsa-15). Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/icmsa-15.2015.58.
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Cui, Han, Zhi Yao, Cheng Tao, and Yuanxun Ethan Wang. "Nonlinear Equivalent-Circuit Model for Thin-Film Magnetic Material Based RF Devices." In 2018 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications (IMWS-AMP). IEEE, 2018. http://dx.doi.org/10.1109/imws-amp.2018.8457165.
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Karami, G. "An Equivalent Continuum-Atomistic Characterization Model for Nanographitic Materials." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81858.
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An equivalent continuum-atomistic algorithm is proposed for carbon-based structures such as nano-scale graphene platelets (NGPs) and carbon nanotubes (CNTs) individually or as stiffeners with polymers. This equivalent continuum-atomistic model will account for the nonlocal effect at the atomistic level and will be a highly accurate mean to determine the bulk properties of graphene-structured materials from its atomistic parameters. In the model, the equivalent continuum and atomic domains are analyzed by finite elements and molecular dynamics finite element-based where atoms stand as nodes in discretized form. Micromechanics idea of representative volume elements (RVE) will be used to determine averaged homogenized properties. In the procedure, a unit hexagonal cell will be the RVE. A minimum volume of material containing this RVE and the neighboring hexagonal cells will be chosen. The size of this volume should cover all the atoms, which have bonded, and nonbonded interaction with the atoms of the RVE unit cell. This minimum volume will be subjected to several load cases. Determination of the response of the RVE hexagonal unit cell contained within the minimum volume, and its potential energy density under the defined load cases, will lead to the determination of mechanical parameters of an equivalent, continuum geometrical shape. For a single layer NGP the thickness of the hexagonal continuum plate is assumed to be 0.34 nm, while in three-dimension and multilayered the actual thickness of layers can be implemented. Under identical loading on the minimum volumes, identical potential (strain) energies for both models will be assumed. Through this equivalence a linkage between the molecular force field constants and the structural elements stiffness properties will be established.
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Provasi, Rodrigo, Fernando Geremias Toni, and Clóvis de Arruda Martins. "Equivalent Model for Interlocked Carcass Under Axial Loads." In ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/omae2016-54381.
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The modelling of flexible pipe interlocked carcasses is complicated when considering all the geometric complexity of their profile. A possible approach is to model them as cylindrical equivalent layers. To follow this path several alternatives can be considered in changing the geometrical and material properties. However, the thickness and the mean radius of those layers must not be changed to not interfere with the diameter of the other flexible pipe layers. In this paper, a model of an orthotropic cylindrical layer, with the same thickness and mean diameter of the original carcass layer is constructed and its material parameters are adjusted for axial loads using a finite element model of the real carcass profile.
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Miranda, E., J. Sune, C. Pan, M. Villena, N. Xiao, and M. Lanza. "Equivalent circuit model for the electron transport in 2D resistive switching material systems." In ESSDERC 2017 - 47th IEEE European Solid-State Device Research Conference (ESSDERC). IEEE, 2017. http://dx.doi.org/10.1109/essderc.2017.8066598.
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Ohadi, A. R., and M. Moghaddami. "Sound Absorption Prediction Using Finite Element Model Based on Modified Biot Poroelastic Model." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95126.
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Simulation of the porous materials based on modified Biot poroelastic model is done in this paper, and the obtained results are compared with the equivalent fluid model available from the literature. The effect of physical parameters of the solid phase and also boundary conditions are studied. For this purpose, the modified Biot equations are obtained in terms of a reduced number of variables. In order to investigate the acoustical behavior of porous materials, the governing equations are simulated using the weighted residual finite element code, developed by the authors. The absorption coefficient diagrams of a selected material are obtained and compared for modified Biot poroelastic model and equivalent fluid model. In addition, the effects of the physical parameters of the solid phase and boundary conditions on the acoustical treatment of the material are studied.
Reports on the topic "Equivalent Material Model"
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Bruce and Yushanov. L52056 Enhancement of PRCI Thermal Analysis Model for Assessment of Attachments. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), August 2004. http://dx.doi.org/10.55274/r0010436.
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Welds made onto in-service pipelines tend to cool at an accelerated rate as the result of the flowing content"s ability to remove heat from the pipe wall. These welds are therefore likely to have high heat-affected zone (HAZ) hardness values and to be susceptible to hydrogen cracking. The use of thermal analysis modeling allows welding parameters (i.e., required heat input levels) to be selected based on anticipated weld cooling rates. Both the Battelle model and the recently developed PRCI Thermal Analysis Model for Hot Tap Welding assume that the pipe material is the most susceptible material being welded. Some attachments (e.g., hot formed fittings, etc.) have a significantly less favorable chemical composition (i.e., higher carbon equivalent level) than the pipe material. As a result, for some in-service welding applications, the attachment material may be more susceptible to cracking than the pipe material. Modifications were made to the finite-element solver of the PRCI model to enable hardness prediction in both the pipe and attachment material. The source code for the modified finite-element solver was provided to Technical Toolboxes - PRCI"s commercial partner for software marketing and distribution. The required modifications to the user interface were also developed. In addition, user interface modifications required to rectify a number of faults that were identified and to improve the user interface were also developed. The incorporation of these enhancements and improvements, which are described herein, will require modification by Technical Toolboxes of the Visual Basic-based version of the software that is currently being marketed (V4.2.1). Following the incorporation of these enhancements and improvements, validation trials should be carried out.
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Sparks, Paul, Jesse Sherburn, William Heard, and Brett Williams. Penetration modeling of ultra‐high performance concrete using multiscale meshfree methods. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/41963.
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Terminal ballistics of concrete is of extreme importance to the military and civil communities. Over the past few decades, ultra‐high performance concrete (UHPC) has been developed for various applications in the design of protective structures because UHPC has an enhanced ballistic resistance over conventional strength concrete. Developing predictive numerical models of UHPC subjected to penetration is critical in understanding the material's enhanced performance. This study employs the advanced fundamental concrete (AFC) model, and it runs inside the reproducing kernel particle method (RKPM)‐based code known as the nonlinear meshfree analysis program (NMAP). NMAP is advantageous for modeling impact and penetration problems that exhibit extreme deformation and material fragmentation. A comprehensive experimental study was conducted to characterize the UHPC. The investigation consisted of fracture toughness testing, the utilization of nondestructive microcomputed tomography analysis, and projectile penetration shots on the UHPC targets. To improve the accuracy of the model, a new scaled damage evolution law (SDEL) is employed within the microcrack informed damage model. During the homogenized macroscopic calculation, the corresponding microscopic cell needs to be dimensionally equivalent to the mesh dimension when the partial differential equation becomes ill posed and strain softening ensues. Results of numerical investigations will be compared with results of penetration experiments.
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Snyder, Victor A., Dani Or, Amos Hadas, and S. Assouline. Characterization of Post-Tillage Soil Fragmentation and Rejoining Affecting Soil Pore Space Evolution and Transport Properties. United States Department of Agriculture, April 2002. http://dx.doi.org/10.32747/2002.7580670.bard.
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Tillage modifies soil structure, altering conditions for plant growth and transport processes through the soil. However, the resulting loose structure is unstable and susceptible to collapse due to aggregate fragmentation during wetting and drying cycles, and coalescense of moist aggregates by internal capillary forces and external compactive stresses. Presently, limited understanding of these complex processes often leads to consideration of the soil plow layer as a static porous medium. With the purpose of filling some of this knowledge gap, the objectives of this Project were to: 1) Identify and quantify the major factors causing breakdown of primary soil fragments produced by tillage into smaller secondary fragments; 2) Identify and quantify the. physical processes involved in the coalescence of primary and secondary fragments and surfaces of weakness; 3) Measure temporal changes in pore-size distributions and hydraulic properties of reconstructed aggregate beds as a function of specified initial conditions and wetting/drying events; and 4) Construct a process-based model of post-tillage changes in soil structural and hydraulic properties of the plow layer and validate it against field experiments. A dynamic theory of capillary-driven plastic deformation of adjoining aggregates was developed, where instantaneous rate of change in geometry of aggregates and inter-aggregate pores was related to current geometry of the solid-gas-liquid system and measured soil rheological functions. The theory and supporting data showed that consolidation of aggregate beds is largely an event-driven process, restricted to a fairly narrow range of soil water contents where capillary suction is great enough to generate coalescence but where soil mechanical strength is still low enough to allow plastic deforn1ation of aggregates. The theory was also used to explain effects of transient external loading on compaction of aggregate beds. A stochastic forInalism was developed for modeling soil pore space evolution, based on the Fokker Planck equation (FPE). Analytical solutions for the FPE were developed, with parameters which can be measured empirically or related to the mechanistic aggregate deformation model. Pre-existing results from field experiments were used to illustrate how the FPE formalism can be applied to field data. Fragmentation of soil clods after tillage was observed to be an event-driven (as opposed to continuous) process that occurred only during wetting, and only as clods approached the saturation point. The major mechanism of fragmentation of large aggregates seemed to be differential soil swelling behind the wetting front. Aggregate "explosion" due to air entrapment seemed limited to small aggregates wetted simultaneously over their entire surface. Breakdown of large aggregates from 11 clay soils during successive wetting and drying cycles produced fragment size distributions which differed primarily by a scale factor l (essentially equivalent to the Van Bavel mean weight diameter), so that evolution of fragment size distributions could be modeled in terms of changes in l. For a given number of wetting and drying cycles, l decreased systematically with increasing plasticity index. When air-dry soil clods were slightly weakened by a single wetting event, and then allowed to "age" for six weeks at constant high water content, drop-shatter resistance in aged relative to non-aged clods was found to increase in proportion to plasticity index. This seemed consistent with the rheological model, which predicts faster plastic coalescence around small voids and sharp cracks (with resulting soil strengthening) in soils with low resistance to plastic yield and flow. A new theory of crack growth in "idealized" elastoplastic materials was formulated, with potential application to soil fracture phenomena. The theory was preliminarily (and successfully) tested using carbon steel, a ductile material which closely approximates ideal elastoplastic behavior, and for which the necessary fracture data existed in the literature.
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Cheng and Wang. L52025 Calibration of the PRCI Thermal Analysis Model for Hot Tap Welding. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), January 2004. http://dx.doi.org/10.55274/r0010298.
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In-service welding is a common industrial practice for both maintenance and repair purpose. Its applications include, but not limited to repair of pipeline damages caused by construction or corrosion, and hot tap welding used to add branch connections to existing pipelines. In-service welding enables maintaining and repairing pipelines without removing them from service. Such welding operations generate significant economic and environmental benefits, for example, no interruption of pipeline operations and no venting of pipeline contents. One of the common problems associated with in-service welding is hydrogen cracking. Pipeline operating conditions combined with unscrupulous welding procedures could lead to high heat-affected zone (HAZ) hardness values and this, in turn, could cause hydrogen cracking. The risk of hydrogen cracking is particularly high for older pipeline materials with high carbon equivalent. The objective of the project was to produce a significantly improved HAZ hardness prediction procedure over the procedure in the current PRCI thermal analysis software by utilizing state-of-the-art phase transformation models for steels. Systematic validation of the prediction algorithms was conducted using extensive experimental data of actual welds. The hardness prediction model is expected to become the basis on which the hardness prediction module of the PRCI thermal analysis software will be upgraded and improved.
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Fischer, Eric, Rebecca McCaughrin, Saketh Prazad, and Mark Vandergon. Fed Transparency and Policy Expectation Errors: A Text Analysis Approach. Federal Reserve Bank of New York, November 2023. http://dx.doi.org/10.59576/sr.1081.
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This paper seeks to estimate the extent to which market-implied policy expectations could be improved with further information disclosure from the FOMC. Using text analysis methods based on large language models, we show that if FOMC meeting materials with five-year lagged release dates—like meeting transcripts and Tealbooks—were accessible to the public in real time, market policy expectations could substantially improve forecasting accuracy. Most of this improvement occurs during easing cycles. For instance, at the six-month forecasting horizon, the market could have predicted as much as 125 basis points of additional easing during the 2001 and 2008 recessions, equivalent to a 40-50 percent reduction in mean squared error. This potential forecasting improvement appears to be related to incomplete information about the Fed’s reaction function, particularly with respect to financial stability concerns in 2008. In contrast, having enhanced access to meeting materials would not have improved the market’s policy rate forecasting during tightening cycles.
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Lui, Mortimer, and Wood. PR-273-0323-R02 Corrosion Assessment Guidance for High Strength Steels (Phase 2). Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), November 2009. http://dx.doi.org/10.55274/r0010703.
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Phase 2 report from GL for assessment of high strength steel affected by corrosion. This work supplements the prior Phase 1 Report (GL Report R9017), issued in August 2009 and incorprates burst test data not previously reported. Extensive research has been carried out for many years by Pipeline Research Council International, Inc. (PRCI) and others to develop methods for assessing the remaining strength of corroded pipelines. This has led to the development of assessment methods such as ASME B31G and RSTRENG. Research by Germanischer Lloyd (hereafter GL1, formerly Advantica) has developed new criteria such as the LPC method and extended the range of assessment methods to include numerical analysis. While there has been substantial progress, there remain areas where existing criteria require improvements. The needed improvements identified include limitations on the interaction of closely spaced defects; the effects of external loading, and cyclic pressure loading. Furthermore, as operators start to use higher strength materials there will be an increasing need to assess the integrity of corroded high strength pipelines and to further validate the application of existing criteria and models to these materials. Phase 1 of the work was conducted to investigate the application of existing assessment methods to high strength pipelines and is described in GL Report R9017. PRCI, the Pipeline and Hazardous Materials Safety Administration (PHMSA) and BP Exploration have funded research to address these issues in recent years. A method for extending the assessment of corroded pipelines of strength grade up to X65, subject to combined internal pressure and external loading, to assess corrosion damage in pipelines subject to cyclic pressure loading, is described in GL Report R9068. In GL Reports R9107, R7702 and, work was undertaken to investigate the performance of methods such as ASME B31G, RSTRENG and LPC when applied to the assessment of higher strength pipeline materials (API 5L/ISO 3183 grade L555/X80 and L690M/X100M). In addition to this work, GL has been commissioned by BP Exploration to conduct an operational trial using 48-inch diameter grade X100 pipe. The operational trial will generate substantial data on long term performance by testing sections of X100 pipeline in near real world conditions. An accelerated operational period will be simulated by two years of pressure cycling, equivalent to forty years operation. This large scale trial will be complemented by a range of laboratory scale tests. During the course of the trial a substantial amount of data related to the assessment of corrosion defects in X100 grade pipe will be gathered. This report presents the results of a program of work that builds on the development work being conducted for PHMSA/PRCI Project #153 and for the corrosion defect assessment section of the BP X100 operational trial.
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Welch, David, and Gregory Deierlein. Technical Background Report for Structural Analysis and Performance Assessment (PEER-CEA Project). Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, November 2020. http://dx.doi.org/10.55461/yyqh3072.
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This report outlines the development of earthquake damage functions and comparative loss metrics for single-family wood-frame buildings with and without seismic retrofit of vulnerable cripple wall and stem wall conditions. The underlying goal of the study is to quantify the benefits of the seismic retrofit in terms of reduced earthquake damage and repair or reconstruction costs. The earthquake damage and economic losses are evaluated based on the FEMA P-58 methodology, which incorporates detailed building information and analyses to characterize the seismic hazard, structural response, earthquake damage, and repair/reconstruction costs. The analyses are informed by and include information from other working groups of the Project to: (1) summarize past research on performance of wood-frame houses; (2) identify construction features to characterize alternative variants of wood-frame houses; (3) characterize earthquake hazard and ground motions in California; (4) conduct laboratory tests of cripple wall panels, wood-frame wall subassemblies and sill anchorages; and (5) validate the component loss models with data from insurance claims adjustors. Damage functions are developed for a set of wood-frame building variants that are distinguished by the number of stories (one- versus two-story), era (age) of construction, interior wall and ceiling materials, exterior cladding material, and height of the cripple walls. The variant houses are evaluated using seismic hazard information and ground motions for several California locations, which were chosen to represent the range seismicity conditions and retrofit design classifications outlined in the FEMA P-1100 guidelines for seismic retrofit. The resulting loss models for the Index Building variants are expressed in terms of three outputs: Mean Loss Curves (damage functions), relating expected loss (repair cost) to ground-motion shaking intensity, Expected Annual Loss, describing the expected (mean) loss at a specific building location due to the risk of earthquake damage, calculated on an annualized basis, and Expected RC250 Loss, which is the cost of repairing damage due to earthquake ground shaking with a return period of 250 years (20% chance of exceedance in 50 years). The loss curves demonstrate the effect of seismic retrofit by comparing losses in the existing (unretrofitted) and retrofitted condition across a range of seismic intensities. The general findings and observations demonstrate: (1) cripple walls in houses with exterior wood siding are more vulnerable than ones with stucco siding to collapse and damage; (2) older pre-1945 houses with plaster on wood lath interior walls are more susceptible to damage and losses than more recent houses with gypsum wallboard interiors; (3) two-story houses are more vulnerable than one-story houses; (4) taller (e.g., 6-ft-tall) cripple walls are generally less vulnerable to damage and collapse than shorter (e.g., 2-ft-tall) cripple walls; (5) houses with deficient stem wall connections are generally observed to be less vulnerable to earthquake damage than equivalent unretrofitted cripple walls with the same superstructure; and (6) the overall risk of losses and the benefits of cripple wall retrofit are larger for sites with higher seismicity. As summarized in the report, seismic retrofit of unbraced cripple walls can significantly reduce the risk of earthquake damage and repair costs, with reductions in Expected RC250 Loss risk of up to 50% of the house replacement value for an older house with wood-frame siding at locations of high seismicity. In addition to the reduction in repair cost risk, the seismic retrofit has an important additional benefit to reduce the risk of major damage that can displace residents from their house for many months.
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McKenna, Patrick, and Mark Evans. Emergency Relief and complex service delivery: Towards better outcomes. Queensland University of Technology, June 2021. http://dx.doi.org/10.5204/rep.eprints.211133.
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Emergency Relief (ER) is a Department of Social Services (DSS) funded program, delivered by 197 community organisations (ER Providers) across Australia, to assist people facing a financial crisis with financial/material aid and referrals to other support programs. ER has been playing this important role in Australian communities since 1979. Without ER, more people living in Australia who experience a financial crisis might face further harm such as crippling debt or homelessness. The Emergency Relief National Coordination Group (NCG) was established in April 2020 at the start of the COVID-19 pandemic to advise the Minister for Families and Social Services on the implementation of ER. To inform its advice to the Minister, the NCG partnered with the Institute for Governance at the University of Canberra to conduct research to understand the issues and challenges faced by ER Providers and Service Users in local contexts across Australia. The research involved a desktop review of the existing literature on ER service provision, a large survey which all Commonwealth ER Providers were invited to participate in (and 122 responses were received), interviews with a purposive sample of 18 ER Providers, and the development of a program logic and theory of change for the Commonwealth ER program to assess progress. The surveys and interviews focussed on ER Provider perceptions of the strengths, weaknesses, future challenges, and areas of improvement for current ER provision. The trend of increasing case complexity, the effectiveness of ER service delivery models in achieving outcomes for Service Users, and the significance of volunteering in the sector were investigated. Separately, an evaluation of the performance of the NCG was conducted and a summary of the evaluation is provided as an appendix to this report. Several themes emerged from the review of the existing literature such as service delivery shortcomings in dealing with case complexity, the effectiveness of case management, and repeat requests for service. Interviews with ER workers and Service Users found that an uplift in workforce capability was required to deal with increasing case complexity, leading to recommendations for more training and service standards. Several service evaluations found that ER delivered with case management led to high Service User satisfaction, played an integral role in transforming the lives of people with complex needs, and lowered repeat requests for service. A large longitudinal quantitative study revealed that more time spent with participants substantially decreased the number of repeat requests for service; and, given that repeat requests for service can be an indicator of entrenched poverty, not accessing further services is likely to suggest improvement. The interviews identified the main strengths of ER to be the rapid response and flexible use of funds to stabilise crisis situations and connect people to other supports through strong local networks. Service Users trusted the system because of these strengths, and ER was often an access point to holistic support. There were three main weaknesses identified. First, funding contracts were too short and did not cover the full costs of the program—in particular, case management for complex cases. Second, many Service Users were dependent on ER which was inconsistent with the definition and intent of the program. Third, there was inconsistency in the level of service received by Service Users in different geographic locations. These weaknesses can be improved upon with a joined-up approach featuring co-design and collaborative governance, leading to the successful commissioning of social services. The survey confirmed that volunteers were significant for ER, making up 92% of all workers and 51% of all hours worked in respondent ER programs. Of the 122 respondents, volunteers amounted to 554 full-time equivalents, a contribution valued at $39.4 million. In total there were 8,316 volunteers working in the 122 respondent ER programs. The sector can support and upskill these volunteers (and employees in addition) by developing scalable training solutions such as online training modules, updating ER service standards, and engaging in collaborative learning arrangements where large and small ER Providers share resources. More engagement with peak bodies such as Volunteering Australia might also assist the sector to improve the focus on volunteer engagement. Integrated services achieve better outcomes for complex ER cases—97% of survey respondents either agreed or strongly agreed this was the case. The research identified the dimensions of service integration most relevant to ER Providers to be case management, referrals, the breadth of services offered internally, co-location with interrelated service providers, an established network of support, workforce capability, and Service User engagement. Providers can individually focus on increasing the level of service integration for their ER program to improve their ability to deal with complex cases, which are clearly on the rise. At the system level, a more joined-up approach can also improve service integration across Australia. The key dimensions of this finding are discussed next in more detail. Case management is key for achieving Service User outcomes for complex cases—89% of survey respondents either agreed or strongly agreed this was the case. Interviewees most frequently said they would provide more case management if they could change their service model. Case management allows for more time spent with the Service User, follow up with referral partners, and a higher level of expertise in service delivery to support complex cases. Of course, it is a costly model and not currently funded for all Service Users through ER. Where case management is not available as part of ER, it might be available through a related service that is part of a network of support. Where possible, ER Providers should facilitate access to case management for Service Users who would benefit. At a system level, ER models with a greater component of case management could be implemented as test cases. Referral systems are also key for achieving Service User outcomes, which is reflected in the ER Program Logic presented on page 31. The survey and interview data show that referrals within an integrated service (internal) or in a service hub (co-located) are most effective. Where this is not possible, warm referrals within a trusted network of support are more effective than cold referrals leading to higher take-up and beneficial Service User outcomes. However, cold referrals are most common, pointing to a weakness in ER referral systems. This is because ER Providers do not operate or co-locate with interrelated services in many cases, nor do they have the case management capacity to provide warm referrals in many other cases. For mental illness support, which interviewees identified as one of the most difficult issues to deal with, ER Providers offer an integrated service only 23% of the time, warm referrals 34% of the time, and cold referrals 43% of the time. A focus on referral systems at the individual ER Provider level, and system level through a joined-up approach, might lead to better outcomes for Service Users. The program logic and theory of change for ER have been documented with input from the research findings and included in Section 4.3 on page 31. These show that ER helps people facing a financial crisis to meet their immediate needs, avoid further harm, and access a path to recovery. The research demonstrates that ER is fundamental to supporting vulnerable people in Australia and should therefore continue to be funded by government.
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COLD FORMED STEEL SHEAR WALL RACKING ANALYSIS THROUGH A MECHANISTIC APPROACH: CFS-RAMA. The Hong Kong Institute of Steel Construction, September 2022. http://dx.doi.org/10.18057/ijasc.2022.18.3.2.
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Cold-formed steel shear wall panels are an effective lateral load resisting system in cold-formed steel or light gauge constructions. The behavior of these panels is governed by the interaction of the sheathing - frame fasteners and the sheathing itself. Therefore, analysis of these panels for an applied lateral load (monotonic/cyclic) is complex due to the inherent non-linearity that exists in the fastener-sheathing interaction. This paper presents a novel and efficient, fastener based mechanistic approach that can reliably predict the response of cold-formed steel wall panels for an applied monotonic lateral load. The approach is purely mechanistic, alleviating the modelling complexity, computational costs and convergence issues which is generally confronted in finite element models. The computational time savings are in the order of seven when compared to the finite element counterparts. Albeit its simplicity, it gives a good insight into the component level forces such as on studs, tracks and individual fasteners for post-processing and performance-based seismic design at large. The present approach is incorporated in a computational framework - CFS-RAMA. The approach is general and thereby making it easy to analyze a variety of configurations of wall panels with brittle sheathing materials and the results are validated using monotonic racking test data published from literature. The design parameters estimated using EEEP (Equivalent Energy Elastic Plastic) method are also compared against corresponding experimental values and found in good agreement. The method provides a good estimate of the wall panel behavior for a variety of configurations, dimensions and sheathing materials used, making it an effective design tool for practicing engineers.