A boundary element method (BEM) implementation of the energy domain integral (EDI) methodology for the numerical analysis of three-dimensional fracture problems considering thermal effects is presented in this paper. The EDI is evaluated from a domain representation naturally compatible with the BEM, since stresses, strains, temperatures, and derivatives of displacements and temperatures at internal points can be evaluated using the appropriate boundary integral equations. Special emphasis is put on the selection of the auxiliary function that represents the virtual crack advance in the domain integral. This is found to be a key feature to obtain reliable results at the intersection of the crack front with free surfaces. Several examples are analyzed to demonstrate the efficiency and accuracy of the implementation.

Migrant farmworker networks are vital components in their job seeking and underemployment minimization strategies. Yet, farmworker cultural, physical, and institutional isolation along with the itinerant and clandestine features of farmwork have become major obstacles in the development of robust lateral communitywide network ties that would otherwise favor reciprocity and resource sharing. Thus, contrary to the positive social capital assumption, we argue that the paucity and fragmented features of farmworkers’ lateral ties have increased their vulnerability and locked them in exploitative relationships in a hostile social environment that makes impractical or impossible the formation of alternative ties. Our study is based on participant observation through a 6‐week stay in three North Carolina farm labor camps. On‐site evidence shows that the two larger groups of solitary male farmworkers and farmworking families break up into smaller groups, each group in pursuit of its own short‐term goals. We conclude that, even though farmworker networks help them to find and ensure temporary jobs, their inability to use the networks to share resources is ultimately detrimental for participants’ long‐term socioeconomic prospects.

SUMMARYA three-dimensional boundary element method (BEM) implementation of the interaction integral methodology for the numerical analysis of mixed-mode three-dimensional thermoelastic crack problems is presented in this paper. The interaction integral is evaluated from a domain representation naturally compatible with the BEM, since stresses, strains, temperatures and derivatives of displacements and temperatures at internal points can be evaluated using the appropriate boundary integral equations. Several examples are analysed and the results compared with those available in the literature to demonstrate the efficiency and accuracy of the implementation to solve straight and curved crack-front problems.

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