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Letteratura scientifica selezionata sul tema "Smash product"

Autore: Grafiati

Pubblicato: 21 settembre 2024

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Articoli di riviste sul tema "Smash product"

1

任, 北上. "Duality between the Smash Product and Smash Coproduct". Advances in Applied Mathematics 06, n. 09 (2017): 1105–14. http://dx.doi.org/10.12677/aam.2017.69134.

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Cinar, Ismet, Ozgur Ege e Ismet Karaca. "The digital smash product". Electronic Research Archive 28, n. 1 (2020): 459–69. http://dx.doi.org/10.3934/era.2020026.

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Guo, Shuangjian, Xiaohui Zhang, Yuanyuan Ke e Yizheng Li. "Enveloping actions and duality theorems for partial twisted smash products". Filomat 34, n. 10 (2020): 3217–27. http://dx.doi.org/10.2298/fil2010217g.

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In this paper, we first generalize the theorem about the existence of an enveloping action to a partial twisted smash product. Then we construct a Morita context between the partial twisted smash product and the twisted smash product related to the enveloping action. Finally, we present versions of the duality theorems of Blattner-Montgomery for partial twisted smash products.

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4

LYDAKIS, MANOS. "Smash products and Γ-spaces". Mathematical Proceedings of the Cambridge Philosophical Society 126, n. 2 (marzo 1999): 311–28. http://dx.doi.org/10.1017/s0305004198003260.

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In this paper we construct a symmetric monoidal smash product of Γ-spaces modelling the smash product of connective spectra. For the corresponding theory of ring-spectra, we refer the reader to [Sch].

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Ma, Tianshui, Haiying Li e Tao Yang. "Cobraided smash product Hom-Hopf algebras". Colloquium Mathematicum 134, n. 1 (2014): 75–92. http://dx.doi.org/10.4064/cm134-1-3.

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KAN, HAIBIN. "THE GENERALIZED SMASH PRODUCT AND COPRODUCT". Chinese Annals of Mathematics 21, n. 03 (luglio 2000): 381–88. http://dx.doi.org/10.1142/s0252959900000406.

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Jia, Ling, e Fang Li. "Global dimension of weak smash product". Journal of Zhejiang University-SCIENCE A 7, n. 12 (dicembre 2006): 2088–92. http://dx.doi.org/10.1631/jzus.2006.a2088.

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8

Mu, Qiang. "Smash product construction of modular lattice vertex algebras". Electronic Research Archive 30, n. 1 (2021): 204–20. http://dx.doi.org/10.3934/era.2022011.

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<abstract><p>Motivated by a work of Li, we study nonlocal vertex algebras and their smash products over fields of positive characteristic. Through smash products, modular vertex algebras associated with positive definite even lattices are reconstructed. This gives a different construction of the modular vertex algebras obtained from integral forms introduced by Dong and Griess in lattice vertex operator algebras over a field of characteristic zero.</p></abstract>

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Nasution, Usman, Muhammad Yan Ahady, Vivi Pratiwi, Fatimah Zahrah Albanjari, Elvita Sari Br Tarigan e Xyena Tesalonika Br Siregar. "Smash Skills In Table Tennis Games". QISTINA: Jurnal Multidisiplin Indonesia 3, n. 1 (1 giugno 2024): 685–88. http://dx.doi.org/10.57235/qistina.v3i1.2376.

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The game of table tennis is a popular sport and is well known by almost all levels of Indonesian society, both in cities and villages, from children to the elderly. The aim of this research is to produce a product in the form of a smash skill instrument in table tennis games, as well as to obtain the validity and reliability of the smash skill instrument in table tennis games. This research uses the research and development (RD) method.

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WANG, DINGGUO, e YUANYUAN KE. "THE CALABI–YAU PROPERTY OF TWISTED SMASH PRODUCTS". Journal of Algebra and Its Applications 13, n. 03 (31 ottobre 2013): 1350118. http://dx.doi.org/10.1142/s0219498813501181.

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Let H be a finite-dimensional cocommutative semisimple Hopf algebra and A * H a twisted smash product. The Calabi–Yau (CY) property of twisted smash product is discussed. It is shown that if A is a CY algebra of dimension dA, a necessary and sufficient condition for A * H to be a CY Hopf algebra is given.

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Più fonti

Tesi sul tema "Smash product"

1

Almoosawi, Somar. "Product Related Research Regarding Small and Medium Sized Enterprises, in Hong Kong and South China, Environmental Management Systems". Thesis, Linköping : Linköping University. Institute of Technology, 2008. http://www.diva-portal.org/smash/get/diva2:114196/FULLTEXT01.

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Gouthier, Bianca. "Actions rationnelles de schémas en groupes infinitésimaux". Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0123.

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Cette thèse porte sur l’étude des actions (rationnelles) des schémas en groupes infinitésimaux, avec un accent particulier sur les schémas en groupes infinitésimaux commutatifs unipotents et les actions génériquement libres et les actions fidèles. Pour tout k-schéma en groupes fini G agissant rationnellement sur une k-variété X, si l’action est génériquement libre, alors la dimension de l’algèbre Lie(G) est majorée par la dimension de la variété. Nous montrons que c’est la seule obstruction lorsque k est un corps parfait de caractéristique positive et que G est infinitésimal commutatif trigonalisable. Si G est unipotent, nous montrons aussi que toute action rationnelle génériquement libre sur X du noyau de (toute puissance du) Frobenius de G s’étend à une action rationnelle génériquement libre de G sur X. De plus, nous donnons des conditions nécessaires pour avoir des actions rationnelles fidèles de schémas en groupes infinitésimaux commutatifs trigonalisables sur des variétés, et des conditions suffisantes (différentes) dans le cas unipotent sur un corps parfait. L’étude des actions fidèles des schémas en groupes sur une variété X fournit des informations sur les sous-groupes représentables du foncteur-groupe des automorphismes AutX de X. Pour tout corps k, PGL2,k représente le foncteur-groupe des automorphismes de P1 k et donc les sous-schémas en groupes de PGL2,k correspondent aux actions fidèles sur P1 k. De plus, PGL2,k(k) coïncide avec le groupe de Cremona en dimension un, c’est-à-dire les morphismes birationnels de P1 k, puisque toute application rationnelle d’une courbe projective non singulière dans elle-même s’étend à la courbe entière. En caractéristique positive, la situation est complètement différente si l’on considère les actions rationnelles de schémas en groupes infinitésimaux. La plupart des actions infinitésimales fidèles sur la droite affine ne s’étendent pas à P1 k. Si la caractéristique d’un corps k est impaire, tout sous-schéma en groupes infinitésimal de PGL2,k se relève à SL2,k. Ceci n’est pas vrai en caractéristique 2 et, dans ce cas, nous donnons une description complète, à isomorphisme près, des sous-schémas en groupes infinitésimaux unipotents de PGL2,k. Enfin, nous prouvons un résultat qui donne une description explicite de tous les k-schémas en groupes infinitésimaux commutatifs unipotents avec algèbre de Lie unidimensionnelle définis sur un corps algébriquement clos k, montrant qu’il y a exactement n tels schémas en groupes non isomorphes d’ordre fixé pn
This thesis focuses on the study of (rational) actions of infinitesimal group schemes, with a particular emphasis on infinitesimal commutative unipotent group schemes and generically free actions and faithful actions. For any finite k-group scheme G acting rationally on a k-variety X, if the action is generically free then the dimension of Lie(G) is upper bounded by the dimension of the variety. We show that this is the only obstruction when k is a perfect field of positive characteristic and G is infinitesimal commutative trigonalizable. If G is unipotent, we also show that any generically free rational action on X of (any power of) the Frobenius kernel of G extends to a generically free rational action of G on X. Moreover, we give necessary conditions to have faithful rational actions of infinitesimal commutative trigonalizable group schemes on varieties, and (different) sufficient conditions in the unipotent case over a perfect field. Studying faithful group scheme actions on a variety X yields information on representable subgroups of the automorphism group functor AutX of X. For any field k, PGL2,k represents the automorphism group functor of P1 k and thus subgroup schemes of PGL2,k correspond to faithful actions on P1 k. Moreover, PGL2,k(k) coincides with the Cremona group in dimension one, i.e. birational self-maps of P1 k, since any rational self-map of a projective non-singular curve extends to the whole curve. In positive characteristic, the situation is completely different if we consider rational actions of infinitesimal group schemes. Most of the faithful infinitesimal actions on the affine line do not extend to P1 k. If the characteristic of a field k is odd, any infinitesimal subgroup scheme of PGL2,k lifts to SL2,k. This is not true in characteristic 2 and, in this case, we give a complete description, up to isomorphism, of infinitesimal unipotent subgroup schemes of PGL2,k. Finally, we prove a result that gives an explicit description of all infinitesimal commutative unipotent k-group schemes with one-dimensional Lie algebra defined over an algebraically closed field k, showing that there are exactly n non-isomorphic such group schemes of fixed order pn

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Young, Christopher. "The Depth of a Hopf algebra in its Smash Product". Doctoral thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/102331.

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Young, Christopher. "The Depth of a Hopf algebra in its Smash Product". Tese, 2014. https://repositorio-aberto.up.pt/handle/10216/102331.

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Shakalli, Tang Jeanette. "Deformations of Quantum Symmetric Algebras Extended by Groups". Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10855.

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The study of deformations of an algebra has been a topic of interest for quite some time, since it allows us to not only produce new algebras but also better understand the original algebra. Given an algebra, finding all its deformations is, if at all possible, quite a challenging problem. For this reason, several specializations of this question have been proposed. For instance, some authors concentrate their efforts in the study of deformations of an algebra arising from an action of a Hopf algebra. The purpose of this dissertation is to discuss a general construction of a deformation of a smash product algebra coming from an action of a particular Hopf algebra. This Hopf algebra is generated by skew-primitive and group-like elements, and depends on a complex parameter. The smash product algebra is defined on the quantum symmetric algebra of a nite-dimensional vector space and a group. In particular, an application of this result has enabled us to find a deformation of such a smash product algebra which is, to the best of our knowledge, the first known example of a deformation in which the new relations in the deformed algebra involve elements of the original vector space. Finally, using Hochschild cohomology, we show that these deformations are nontrivial.

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Welsh, Charles Clymer. "Some results in crossed products and lie algebra smash products". 1990. http://catalog.hathitrust.org/api/volumes/oclc/22425708.html.

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Libri sul tema "Smash product"

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Conference on Hopf Algebras and Tensor Categories (2011 University of Almeria). Hopf algebras and tensor categories: International conference, July 4-8, 2011, University of Almería, Almería, Spain. A cura di Andruskiewitsch Nicolás 1958-, Cuadra Juan 1975- e Torrecillas B. (Blas) 1958-. Providence, Rhode Island: American Mathematical Society, 2013.

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2

Bruner, R. R. H. Springer, 1986.

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3

Partial Dynamical Systems, Fell Bundles and Applications. American Mathematical Society, 2017.

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Capitoli di libri sul tema "Smash product"

1

Yan, Yan, e Lihui Zhou. "Separability Extension of Right Twisted Weak Smash Product". In Advances in Intelligent and Soft Computing, 103–7. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-14880-4_12.

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Ngompé, Arnaud Ngopnang. "Homeomorphic Model for the Polyhedral Smash Product of Disks and Spheres". In Toric Topology and Polyhedral Products, 253–75. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-57204-3_13.

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Yan, Yan, Nan Ji, Lihui Zhou e Qiuna Zhang. "Some Properties of a Right Twisted Smash Product A*H over Weak Hopf Algebras". In Communications in Computer and Information Science, 101–8. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-16336-4_14.

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Nastasescu, Constantin, e Freddy Van Oystaeyen. "7. Smash Products". In Methods of Graded Rings, 187–221. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-540-40998-4_7.

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Jardine, J. F. "Smash products of spectra". In Generalized Etale Cohomology Theories, 1–29. Basel: Springer Basel, 1997. http://dx.doi.org/10.1007/978-3-0348-0066-2_1.

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6

Lewis, L. G., J. P. May e M. Steinberger. "Twisted half smash products and extended powers". In Lecture Notes in Mathematics, 299–349. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/bfb0075785.

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Shaoxue, Liu, e Fred Oystaeyen. "Group Graded Rings, Smash Products and Additive Categories". In Perspectives in Ring Theory, 299–310. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2985-2_26.

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Lewis, L. G., e J. P. May. "Change of universe, smash products, and change of groups". In Lecture Notes in Mathematics, 54–116. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/bfb0075781.

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Doi, Yukio. "Generalized Smash Products and Morita Contexts for Arbitrary Hopf Algebras". In Advances in Hopf Algebras, 39–53. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9781003419792-3.

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Ilankovan, Velupillai, e Tian Ee Seah. "Surgical Facelift". In Oral and Maxillofacial Surgery for the Clinician, 759–73. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-1346-6_37.

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AbstractWith aging, a combination of gravitational forces, laxity of the skin due to loss of elasticity, decreased dermal thickness and loss of dermal appendages results in ptotic, hanging skin. Face lift or rhytidectomy as its name suggest is a procedure to partially eliminate folds, creases and wrinkles (rhytids) caused by gravity and degeneration. The creation of two large cervicofacial flaps which after suspension and trimming, produces an overall tightening the skin and the fascial envelope of the face and neck results in restored anatomical structure. Treatment of the SMAS layer is important and can be broadly categorized into 3 methods. They are plication, elevation and imbrication and SMASectomy. Platysma elevation and plication can be carried out simultaneously for the neck. Face lift can help to negate some of these gravitational problems and produce some intrinsic improvement. Complications include haematoma, skin ischaemia and necrosis, obvious scarring, sensory disturbances, motor nerve disturbances and ear lobe irregularities.

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Atti di convegni sul tema "Smash product"

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Hadzihasanovic, Amar. "The Smash Product of Monoidal Theories". In 2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS). IEEE, 2021. http://dx.doi.org/10.1109/lics52264.2021.9470575.

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Zhao Lihui. "Generalized L-R smash products and diagonal crossed products of multiplier Hopf algebras". In 2011 International Conference on Multimedia Technology (ICMT). IEEE, 2011. http://dx.doi.org/10.1109/icmt.2011.6002679.

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Konh, Bardia. "Finite Element Studies of Triple Actuation of Shape Memory Alloy Wires for Surgical Tools". In 2018 Design of Medical Devices Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/dmd2018-6857.

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Since the early discovery in 1951 [1], shape memory alloys (SMAs) have been used in design and development of several innovative engineering systems. SMAs’ unique characteristics have introduced unconventional alternatives in design and development of advanced devices. SMA’s field of applications has covered many areas from aerospace to auto industries, and medical devices [2]. During the past couple of decades, scientists have suggested material models to predict the SMA’s shape memory effect (SME) and its superelastic behavior. The superelastic characteristic of SMAs (its capability to exhibit a large recoverable strain) has been widely used to develop innovative products including biomedical implants such as stents, artificial heart valves, orthodontic wires, frames of indestructible spectacles, etc. However, its actuation capabilities, known as SME, hasn’t been thoroughly expanded. The number of products privileging from SMA’s SME behavior has been very limited. The reason relies on the SMA’s complex material properties that depend on the stress, strain and temperature at every stage of actuation as well as the material’s processing and the thermomechanical loading history.

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Montagnoli, Andre, Marcus L. Young, Christoph Somsen, Jan A. Frenzel, F. Tad Calkins e Douglas E. Nicholson. "Processing and Thermomechanical Stability of Low Hysteresis Shape Memory Alloys". In SMST 2024. ASM International, 2024. http://dx.doi.org/10.31399/asm.cp.smst2024p0117.

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Abstract NiTi shape memory alloy (SMA) actuators have gained much attention in recent years because of their ability to combine high actuation forces to a significantly smaller component size. Binary SMAs containing Ni and Ti, however, suffer from relatively poor functional and structural fatigue, which requires training. Binary NiTi SMAs also possess a relatively wide hysteresis gap between the austenite final and martensite final temperatures (ΔTMfAf), which demands more energy to produce each actuation stroke. Zarnetta et al. have shown that small additions of substitutional elements to the NiTi-based SMA can significantly improve those conditions by increasing the coherency between the two transforming crystal structures. Two quaternary NiTiCuPd SMAs were selected based on combinatorial studies from X-ray diffraction data and their results were analyzed concerning their hysteresis width and thermal-mechanical stability.

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De Nardi, Alice, Andrea Marinelli, Flavia Papile e Andrea Cadelli. "Hoyo – Shape Memory Alloys enable a new way to approach the treatment of the Autism Spectrum Disorder". In Intelligent Human Systems Integration (IHSI 2022) Integrating People and Intelligent Systems. AHFE International, 2022. http://dx.doi.org/10.54941/ahfe100943.

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Sensory disorders characterise 90% of individuals with an autistic spectrum disorder (ASD); however, each individual is unique. Hoyo is an innovative product that fits the single sensory profile of the child. The device provides complex sensorial stimulation to the trunk of the user’s body thanks to a series of inflatable bladders. To do so, Hoyo features shape memory alloys (SMAs), which provide a compact, lightweight, and silent system. Indeed, such properties are all essential characteristics for a product dedicated to ASD. Therapists can program the system to adapt Hoyo to the child’s needs rather than asking the child to accommodate an existing product. Being able to release the tension caused by an over-stimulating environment is the first step towards achieving a higher level of inclusion in the educational system.

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Kilic, Ugur, Muhammad M. Sherif, Sherif M. Daghash e Osman E. Ozbulut. "Full-Field Deformation and Thermal Characterization of GNP/Epoxy and GNP/SMA Fiber/Epoxy Composites". In ASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/smasis2019-5640.

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Abstract Shape memory alloys (SMAs) are a class of metallic alloys that possess remarkable characteristics such as superelasticity and shape memory effect. Superelastic SMAs have been considered as fiber in polymer composites due to their ability to recover their deformation upon removal of load, good energy dissipation capacity and impact resistance. Graphene nanoplatelets (GNPs) consists of small stacks of graphene sheets that are two-dimensional. Both sides of atomic lattice of GNPs contact matrix of a composite system and can generate more sites for potential chemical and physical bonding with the host material. Most importantly, graphene sheets and their derivatives can be produced at large-scale for industrial demand at low-cost. This study explores the fabrication of multi-scale reinforced epoxy matrix composites in which GNPs and SMA strands are employed as nano- and micro-scale reinforcements, respectively. First, GNPs are dispersed into a ductile and brittle epoxy matrix to produce GNP/epoxy nanocomposites. To study the effect of GNP content on the behavior of the developed nanocomposite, GNPs are added to the epoxy-hardener mixture at different weight percentages (neat, 0.1%, 0.25%, 0.5%, 1%, and 2%). Uniaxial tensile tests of the developed nanocomposites are conducted under monotonic load up to failure. The optimum GNP content for GNP-reinforced epoxy matrix is determined and used in the fabrication of SMA fiber/epoxy composite. The developed multiscale reinforced epoxy composites are tested under tensile loading and their full-field strain and temperature behavior are monitored and evaluated using a digital image correlation system and an infrared thermal camera.

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Shaw, John A., Antoine Gremillet e David S. Grummon. "The Manufacture of NiTi Foams". In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-39028.

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Ongoing research is presented on processing of NiTi-based shape memory alloy (SMA) foams. The aim is to demonstrate a new class of materials that combine the advantages of light-weight metallic foams with the strain recovery and energy-dissipation capability of SMAs. There are a number of potential novel structural and biomedical applications that could be enabled by the unusual passive and active properties of such a material. This paper presents initial results on our attempt to fabricate functional prototype specimens using a polymeric foam precursor and a powder metallurgy process to produce NiTi foams with user-selected topology and relative density. It is shown that open-cell NiTi foams with relative density less than 5% can be produced with this technique. While definite martensitic transformational behavior has been achieved in the prototypes, the quality of the foams are found to be sensitive to the sintering temperature, the binder system employed, and the levels of interstitial contamination. Further work is needed before good superelastic and shape-memory properties can be demonstrated. Nevertheless, the current technique appears promising, since the method is capable of producing NiTi foam with a more regular structure and at a relative density nearly an order of magnitude less than other techniques currently used to produce porous NiTi.

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Song, Di, Guozheng Kang, Qianhua Kan e Chao Yu. "Observations on the Residual Martensite Phase of NiTi Shape Memory Alloy Micro-Tubes Under Uniaxial and Multiaxial Fatigue-Loadings". In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65478.

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NiTi shape memory alloys (SMAs) are widely used in astronautics and bio-medical fields due to their shape memory property, superelasticity and excellent biological compatibility. In such applications, the NiTi SMA devices are often subjected to a kind of strain- or stress-controlled cyclic loading, leading to the fatigue failure of NiTi SMAs is a key issue that should be investigated. Meanwhile, with the ambient temperature higher than austenite transformation finish temperature (Af), the NiTi SMAs can transform into martensite phase during loading process and recover their austenite phase during unloading, the unique martensite transformation and its reverse of NiTi SMAs indicates their fatigue failure characters much different from ordinary metals. Thus, besides cyclic-loading experiments, the micro-structure observations on the morphology of residual martensite on fracture surfaces is also an important component of investigating the damage mechanisms of NiTi SMAs, which should be taken into considered as well. This paper aims at the micro-structure observations on the fractured NiTi micro-tubes after both uniaxial and multiaxial stress-controlled fatigue loadings, in which the morphology of residual martensite affected by different stress levels and loading paths are compared and analyzed. The results show that the bigger-sized residual martensite phase is inclined to appear in the loading cases with higher stress level or multiaxial paths, corresponding to the higher residue deformations in the fatigue-loading tests. Meanwhile, in multiaxial loadings, due to the effect of gradually increased shear stress along the radial direction, it leads to the size of residual martensite near the outer surface of the NiTi micro-tubes much bigger than that near the inner surface, whereas in uniaxial loadings, the distribution of martensite phase are nearly uniform on the cross section of NiTi specimens. It can be also found that the locations near the internal defects tend to produce bigger sized martensite phase as well, which indicates the stress-concentration effect induced therein. Moreover, the morphology of mutually hindered martensite phase in different directions can be also observed in the fractured specimens, it implies the propagation of the micro-cracks which caused by the transformation induced plasticity between the interface of austenite and martensite will be further prevented, leading to the relatively slower crack propagation rate of NiTi SMAs than ordinary metals. The findings can provide experimental support to investigating the damage mechanisms of NiTi SMAs in microscopic field, and it is also the foundation of establishing the reasonable damage evolution model and life prediction model of NiTi SMAs, describing their distinctive fatigue characters in both uniaxial and multiaxial loading conditions.

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Worrell, Dominique, Faith Gantz, Linden Bolisay, Art Palisoc e Marcus L. Young. "Shape Memory Alloy Design for a Lightweight and Low Stow Volume Expandable Solar Concentrator". In SMST 2024. ASM International, 2024. http://dx.doi.org/10.31399/asm.cp.smst2024p0115.

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Abstract Solar concentrators increase the amount of usable energy available in solar collection systems by focusing energy through an aperture to which energy is magnified within the area of its trajectory. Design challenges of a solar concentrators for space applications are to make them more lightweight, compact, and exhibit a smooth and consistent reflective surface curvature for optimal performance. Shape memory alloys (SMAs) offer an effective and compact solution to engineering needs, such as solar reflectors, to reduce weight and improve overall energy collection and concentration performance. The one-way shape memory effect can be used for this application, where the SMA is heat treated in a strained designed curvature by forcing the austenite microstructure to “remember” the original shape even after deformation. SMAs are capable of actuating from the stow configuration and into the designed shape after the solar energy exposure induces a phase transformation. In this study, NiTi and NiTiCu SMAs were thermomechanically processed into plates and cut into three sizes of triangular chips for use as reflector components. Standard binary NiTi SMAs was modified with the substitution of Cu for Ni to achieve a narrower hysteresis and better thermomechanical cycling stability. The SMAs were produced from commercially available NiTi SM495 plates by ATI Specialty Alloys and Components (Albany, OR) and custom-melted NiTiCu buttons. Each processing step was comprehensively characterized to monitor microstructural and thermomechanical property changes using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Vickers hardness (HV). The NiTi and NiTiCu triangular chips were shape-set utilizing a custom-made apparatus to attain the intended curved surface with specific dimensions for a reflector component within a solar concentrator.

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Hoffmann, Fabian, Robin Roj, Ralf Theiß e Peter Dültgen. "Development of Shape Memory-Based Elastic-Adaptive Damping Elements for Sport and Rehabilitation Equipment". In ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/smasis2020-2255.

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Abstract The generation and variation of forces necessary to achieve a training stimulus is often realized in sports and rehabilitation equipment by manually adjustable masses or by complex motor-brake systems. This leads to heavy and unwieldy systems, which cannot be used flexibly, and in addition to high costs. The main objective of this paper is to prove that pseudoelastic shape memory alloys (SMA) are potentially suitable for use in sports and rehabilitation equipment and offer additional value in the area of training flexibility combined with high training resistance. Therefore, the properties of pseudoelastic SMAs for this application were investigated. These multifunctional materials offer the potential for special elastic and sensory properties. The pseudoelastic effect is based on stress-induced martensite formation, which allows high elastic deformations. During this phase transformation, the mechanical stress passes through a plateau. The stress plateau can be moved by changing the temperature of the SMA. The determination of properties of pseudoelastic SMAs with different alloy compositions was carried out according to the specifications of “VDI 2248: Product Development with Shape Memory Technology”. With a functional model based on the material tests, which replaces a commercially available force clamping device, the monitoring of force, displacement and temperature changes can be realized by the integrated sensor technology. This paper presents the methodology, experiments and findings for the use of pseudoelastic SMAs in sport and rehabilitation devices. It concludes with prospects to commercial application.

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