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We present a phase-field model for fracture in Kirchoff-Love thin shells using the local maximumentropy (LME) meshfree method. Since the crack is a natural outcome of the analysis it does not require an explicit representation and tracking, which is advantage over techniques as the extended finite element method that requires tracking of the crack paths. The geometric description of the shell is based on statistical learning techniques that allow dealing with general point set surfaces avoiding a global parametrization, which can be applied to tackle surfaces of complex geometry and topology. We show the flexibility and robustness of the present methodology for two examples: plate in tension and a set of open connected pipes.

In this paper. we develop a method based on local maximum entropy shape functions together with enrichment functions used in partition of unity methcx:ls to discretize problems in linear elastic fracture mechanics. We obtain improved accuracy relative to the standard extended finite element method at a comparable computational cost. In addition. we keep the advantages of the LME shape functions. such as smootlmess and non-negativity. We show numerically that optimal convergence (same as in FEM) for energy norm and stress intensity factors can be obtained through the use of geometric (fixed area) errriclnnent with no special treatment of the nodes near the crack such as blending or shifting.Keywords Local maximum entropy· Convex approximation· Meshless methods· Extrinsic enrichment S. P. A. Bordas's ORCID ID is 0000-0001-7622-2193.

Background and objectivesThe world’s growing elderly population highlights the necessity for further attention to the psychological problems of the elderly, such as death anxiety. Analysis of the elderly’s perception of aging and associated factors can contribute to prediction of their future physical and mental health. The purpose of this study was to determine the relationship of perception of aging, and a group of demographic factors, with death anxiety in the elderly living in Gonabad, Iran.Subjects and methodsThis analytical descriptive study was conducted on 330 elderly residents of Gonabad, who were selected by stratified random sampling. Research tools were a standard demographic questionnaire, Barker’s Brief Aging Perceptions Questionnaire, and Collett–Lester Fear of Death Scale. Data were collected by interview of respondents at their home. Data analysis was carried out in SPSS 16 using descriptive statistics, analysis of variance, Pearson’s test, independent t-test, and linear regression.ResultsRespondents had a mean age of 73.97±7.68 years, 42.4% of respondents were men and 57.6% were women. The total Barker’s Brief Aging Perceptions Questionnaire score was 63.18±8.75, with the highest score (17.10±4.70) associated with negative consequences and control. The total Collett–Lester Fear of Death Scale score was 128±14.80, with the highest score (35.13±4.06) pertaining to the subscale fear of other people’s death. Regression results indicated that the death anxiety score was predictable according to the age and all dimensions of perception of aging, except for the consequences and negative control dimension.ConclusionAge and the perception of aging are good predictors of death anxiety. The authors recommend further research on the determinants of death anxiety in the elderly and the development of a comprehensive care plan to reduce this anxiety among Iranian elderly.

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