230 research outputs found
Designing preservation. Integrating the architectural project to UNESCO tools to tackle territorial fragility: the Tivoli case as a pilot experience
No full textThe research investigates the potential contribution of a design-based approach to the current institutional UNESCO safeguard tools concerning the relation core/territory, challenging the conservative role of buffer zones that lead to stalemate situations in terms of territorial development, especially in the Italian context. Through the analysis of case studies, a methodological approach is developed that focuses on the one hand on the use of design tools for the assessment of heritage-related territories (cognitive framework), and on the other hand on the use of design actions in the management strategies for valorisation (interpretation framework). These tools are tested on the relevant experimental case of Tivoli, seat of two major World Heritage sites, as a pilot experience of integration of design tools in safeguard and management strategies for the solution of territorial fragility in complex heritage-related contexts
On the relations between subgroups of a group and submodules of modules over group rings
No full textLet R be a commutative ring and G a finite group. In [1], using a structure on an R module M to make it an RG module, we find some relations between RG submodules and a subgroups. We also prove that for each normal subgroup H of G with an invertible IHI in R, there is a direct summand RG submodule of M
Modeling of plastic deformation due to slip-its implications in characterizing fatigue crack growth thresholds and non-Schmid behavior in transforming alloys
No full textThis study will be divided into two main pillars in interrogating the microstructural barriers prevalent at the nanoscale: (i) the effect of twin and grain boundaries along with their contribution on the irreversibility of the crack-tip emitted slip under cyclic fatigue loading, (ii) the atomistic scale lattice resistance against glide motion of dislocations in a perspective of laying out the dislocation core-crystal structure and applied loading interplay in particular embracing the plastic behavior in ordered shape memory alloys. The primary goal of the current work is to provide physical insight for the implications of the slip-mediated plasticity in fatigue crack growth and non-Schmid behavior on both experimental and theoretical grounds.
In first part of the current study, the near threshold fatigue crack growth behavior of nanocrystalline Ni-2.89% wt. Co (Ni-Co) alloy with nanotwinned microstructure will be characterized in particular based on the contribution of microstructural variables such as the on-going crack-tip emitted dislocation and twin/grain boundary (i.e. of , and types) interactions, the pre-existing dislocation density and the characteristic dimensions of grain size, twin thickness and spacing. In order to accomplish this task, we architectured the microstructure of nanocrystalline Ni-Co alloy by conducting annealing treatments at various temperatures and promoted grain-twin coarsening as well as varying the pre-existing slip density. Furthermore, we conducted experiments on these engineered microstructures under uniaxial tension and cyclic fatigue loading employing Digital Image Correlation technique at different length scales. The monotonic tension experiments enables to characterize the contribution of microstructural variables on the mechanical response of Ni-Co alloy, such as ductility and strength. On the other hand, the cyclic fatigue crack growth experiments help identify the variation of crack growth behavior and threshold levels of Ni-Co alloy along with the architectured microstructures. The experimental measurements show that nanotwins hierarchically embedded in the microstructure of Ni-Co alloy promotes ductility and fatigue threshold in a profound fashion with decreasing characteristic dimensions.
Meanwhile, the primary focus is on nanocrystalline Ni-Co alloy, the current work has been put forward to establish a physical model informed by the multi-scale microstructural parameters which is capable of predicting the fatigue threshold levels of metallic materials devoid of empiricism. To that end, we simulated the interaction of crack-tip emitted slip and the grain/twin boundaries within the framework of Molecular Dynamics and characterized the on-going dislocation reactions as well as the crystalline resistance at the boundary against the glide of dislocations participating in these reactions. Subsequently, the effective threshold stress intensity factor range metric is predicted on theoretical grounds by incorporating physical parameters such as the friction stresses both inside the pristine crystal and at the grain/twin boundaries along with the glide geometry associated with the prevailing dislocation reactions into the continuum scale dislocation motion equations. The modelling efforts for cyclic glide motion of crack-tip emitted dislocations as a function of applied stress factor range , , provided a quantitative basis to determine the microstructure-sensitive crack threshold levels on theoretical grounds. The results indicate that coherent twin boundaries ( type ) impart superior fatigue properties to Ni-Co alloy compared to the less-coincident grain boundaries of and types. As a distinguishing finding of the present study, the increasing frequency of the grain and twin boundaries-linked with the grain size and twin spacing & thickness- are determined to promote the fatigue threshold levels in Ni-Co alloy.
In the second part of the study, the mechanisms governing the slip-mediated plasticity of the ordered shape memory alloys, particularly Fe3Al and NiTi, are focused on both experimental grounds (via Digital Image Correlation technique) and employing theoretical atomistic scale dislocation core simulations. The non-Schmid character of the plastic response profoundly governs on the functional performance of this class of alloys imparting tension-compression asymmetries and anisotropic glide resistance as a function of crystal orientation. To accomplish this task, the dislocation core structures are calculated employing Molecular Statics-Dynamics simulations and subsequently the interaction mechanisms of the non-planar dislocation core structure with applied stress tensor components are identified considering the corresponding crystal symmetries involved. The dislocation core shape that is governed by the atomistic scale disregistry distributions under applied loading is demonstrated to play a decisive role on the anisotropic glide resistance which results in deviations from the Schmid law. The theoretical predictions for the anisotropic glide resistance are demonstrated to be in well agreement with the high magnification experiments conducted on single crystals of these alloys. The current methodology followed enables us to build a comprehensive understanding for the non-Schmid glide behavior of dislocations in austenitic phase of Fe3Al and NiTi shape memory alloys considering the effects of both glide and non-glide stress components. Furthermore, generalized yield criteria for these materials are established extending atomistic scale core mechanics to the macro-scale crystal plasticity.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2019-12-01The student, Sertan Alkan, accepted the attached license on 2017-12-05 at 13:43.The student, Sertan Alkan, submitted this Dissertation for approval on 2017-12-05 at 14:02.This Dissertation was approved for publication on 2017-12-06 at 10:46.DSpace SAF Submission Ingestion Package generated from Vireo submission #11864 on 2018-03-13 at 09:56:57Made available in DSpace on 2018-03-13T15:25:27Z (GMT). No. of bitstreams: 3
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Prospective teachers' views and experiences with e-portfolios
No full textThe use of electronic portfolios (e-portfolios) is a burgeoning area ofresearch, with many teacher education programs utilising as botha product of and a process of reflective practice. This case studyaimed to explore prospective primary teachers’ (students) percep-tions, perspectives and experiences of the use of e-portfolios, focus-ing on the affordances and limitations of using e-portfolios in InitialTeacher Education (ITE). Eleven second-year undergraduate stu-dents from secondary and primary ITE programs were interviewed.A reflexive thematic analysis was conducted on the transcripts, inwhich the module tutors’ experiences were also incorporated.Findings suggest that e-portfolios can be valuable agentic andreflective pedagogical tools that can scaffold learning, althoughwith a number of important caveats for future implementations.This paper speaks to the paucity of research that extends the viewof e-portfolios as simply repositories for content.ARTICLE HISTORYReceived 11 December 2023Accepted 27 August 2024KEYWORDSE-portfolio; reflection; initialteacher education; ScotlandIntroductionThe definition and application of reflection, especially in initial teacher education, is bothcontested and complex. Typically, Dewey’s (1933) book called How We Think and Schön’s(1983) work on becoming a reflective practitioner are regarded as the foundational textsin this area. Dewey defined reflection as ‘an operation in which facts on one side andmeaning on the other are elicited through constant interaction with each other’ (1933,p. 165). Schön (1983) further developed this idea, emphasising the importance of thedevelopment of ‘feeling for practice’ within specific contexts. He highlighted the signifi-cance of uncertainties in his discussion on reflection, noting that ‘it is our capacity to see-as and do-as that allows us to have a feel for problems that do not fit existing rules’ (1983,p.140). Similarly, LaBoskey (1993), who argued that reflection should clearly be an objec-tive for all teachers, stated that ‘reflection begins when an individual is perplexed oruncertain about an idea or situation and ends with a judgement’ (p.10). The process bywhich these judgements are formed and can be documented was further examined byCONTACT Sinem Hizli Alkan [email protected] School of Education, Faculty of Arts, Humanities,Education and Social Sciences, Anglia Ruskin University, Bishop Hall Lane, Chelmsford CM1 1SQ, UKREFLECTIVE PRACTICEhttps://doi.org/10.1080/14623943.2024.2398800© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properlycited. The terms on which this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) orwith their consent.</p
Late Pleistocene changes in terrestrial biomarkers in sediments from the central Arctic Ocean
No full textBiomarkers in Late Pleistocene sediments collected from the Integrated Ocean Drilling Program (IODP)-Arctic Coring Expedition (ACEX) Hole M0004C (central Arctic Ocean) were investigated. The major biomarkers are long-chain n-alkanes, n-fatty acids and n-alkan-1-ols, indicating fresh organic matter (OM) derived predominantly from higher plants. The dominance of terrestrial biomarkers is attributed to severe OM degradation caused by slow sedimentation in oxygen-rich benthic water and/or low primary production due to permanent sea-ice coverage. Hopanes, representing thermally altered OM, tend to be abundant in samples with abundant ice rafted debris (IRD). An OM-rich dark grey layer deposited during marine isotope stage (MIS) 6 contains a significant amount of branched glycerol dialkyl glycerol tetraethers (branched GDGTs), suggesting ice erosion of organic-rich continental soil followed by transportation to the central Arctic by drifting ice. The labile–refractory index (i.e., the abundance ratio of long-chain n-alkan-1-ols to the sum of long-chain n-alkanes and long-chain n-alkan-1-ols) decreases above the dark grey layer, indicating that the OM became more refractory. This change suggests that coverage of the source region by OM-rich soil decreased because of extensive glacial erosion during MIS-6
Erratum: Using the Mixed-Meta Method to Assess Portfolios in Science Teaching
No full textThe corrections should be made as below,
The (Alkan et al., 2019) used in the Methods section needs to be deleted. The Alkan et al. study is a mixed method [(Mixed methods design: a narrative literature review. Journal of Qualitative Research in Education, 7(2):559-582)]. However, the term used in our study is mixed-meta method. In addition, the term belongs to a different author and it has a completely different definition. (On the pages 3900 and 3914).
Instead of “(Büyüköztürk et al., 2018 p.259-260)” (Batdı, 2020, p.3) should be added under the title “Meta-analysis procedure”. (On the page 3903)
Mining Istanbul. A Project for an urban refinery.
No full textPublic BuildingArchitecture and The Built Environmen
Retrospective analysis of the effect of breast surgery on body posture in patients with early-stage breast cancer after cancer treatment (VENUS study) (Breast cancer and body posture)
No full textBackground/aim: The aim of this study was to determine whether breast surgery changes body posture in patients with early-stage breast cancer. Materials and methods: Study variables include age, side and localization of the tumor in the breast, applied breast surgery, axillary interference, pathological tumor size, axillary lymph node metastasis, body mass index, bone density, adjuvant therapies, and histological type. Thoracic kyphosis angle due to the anatomically affected primary region to detect changes in body posture and Cobb’s method were used to measure this. Results: There was a statistically significant difference in the mean Cobb’s angle between the follow-up times of 57 patients (P < 0.001), with a cumulative increase in the Cobb’s angle from baseline to the second year. As the age of the diagnosis progressed, the Cobb’s angle increased significantly at 2 years when compared to baseline (r = 0,616, P < 0,001). In terms of baseline, the higher the BMI level in the 2nd year, the higher the Cobb’s angle in the 2nd year as compared to the baseline (r = 0,529, P < 0,001). Conclusion: It was concluded that the increase in thoracic kyphosis in patients with breast cancer should be examined psychosocially. The study should be supported by a larger number of patients.We would like to thank the radiologist Assistant of Professor Dr. Rabia KILINÇ, who acts as a controller for measuring the Cobbs angles of our patients and helps with the acquisition of images for the absence of any conflicts of interest. Since this study is Dr. Ozan Ahmet ÇETİN internal medicine specialization thesis, Dr. Rabia KILINÇ is not included in the author ranking
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