Fatigue failure in metal bellows due to flow-induced vibrations

To prevent fatigue due to flow-induced vibrations in metal bellows connected to ducts carrying liquid hydrogen, a study was made which shows that the flexure lines are in general a function of the vibration coupling between the fluid and bellows structure, and the nature of the external environment

I Am the People

I. I ride the street cars, The dirty, sweat-smelling street cars everyday..

Coral Restoration: Comparisons in Space, Time, Impacts, and Costs

Seventy-five percent of coral reefs globally face crisis due to anthropogenic disturbances, prompting heightened global coral restoration initiatives to preserve these vital ecosystems. Various regions employ diverse active coral restoration methodologies, including coral gardening, transplantation, micro-fragmentation, artificial reefs, and sexual propagation. Of these methods, coral gardening stands out as one of the most common and highly successful methods, alongside widespread transplantation practices. Restoration efforts predominantly focus on acroporids due to their relatively rapid growth and asexual fragmentation; however, a diverse range of coral species, including large, slow-growing varieties, is also employed in these endeavors. Costs vary significantly, ranging from $10,000 to$50,000,000 USD per hectare, contingent on restoration methods and locations. Coral restoration does not address the whole problem though, achieving optimal coral survivorship post-restoration involves integrating ecological processes, coral density, and arrangement. In a Bonaire study, I utilized established coral reef monitoring sites, creating 100 m2 quadrats to assess A. cervicornis and A. palmata population density and vigor. Among 11 long-term monitoring sites, three were active restoration sites (1,796 acroporid coral outplants), three were adjacent control reefs, and five were regional control reefs. No acroporids were found at 10 m depth, but at 5 m depth, 13 acroporids were recorded at four survey sites, with five from outplant sites. The two sites with the highest acroporid densities were Calabas (restoration site) and Karpata (control site). The efficacy of coral restoration remains inconclusive based on this study of Bonaire\u27s long-term monitored reefs

Unsheltered homelessness among veterans: correlates and profiles

We identified correlates of unsheltered status among Veterans experiencing homelessness and describe d distinct subgroups within the unsheltered homeless Veteran population using data from a screening instrument for homelessness that is administered to all Veterans accessing outpatient care at a Veterans Health Administration (VHA) facility . Correlates o f unsheltered homelessness included male gender, white race, older age, lower levels of VHA eligibility, substance use disorders, frequent use of VHA inpatient and infrequent use of VHA outpatient services, and residing in the West. We identified six disti nct subgroups of unsheltered Veterans; the tri - morbid frequent users represented the highest need group, but the largest group was comprised of Veterans who made highly infrequent use of VHA healthcare services. Differences between sheltered and unshelter ed Veterans and heterogeneity within the unsheltered Veteran population should be considered in targeting housing and other interventions.National Center on Homelessness Among Veteran