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What automated composite laminate manufacturing isWhy automation is of interest in science applicationsHow composite automation is being considered for science instrument applicationsAnd, about test data showing high stiffness materials processed with automation results in reduced material strength while stiffness and coefficient of thermal expansion are mostly unaffected.

Objective Risk management (RM) is a cyclical process of identifying and ranking risks, implementing controls, and evaluating their effectiveness. This study aims to identify effective RM interventions in the U.S. mining industry. Methods RM interventions were identified in four companies representing metal, aggregate, and coal mining sectors. Injury rates were determined using Mine Safety and Health Administration (MSHA) data and changes in injury rates identified through change point analysis. Program implementation costs and associated changes in injury costs were evaluated for select interventions. Results Six of 20 RM interventions were associated with a decline in all injuries and one with a reduction in lost-time injuries, all with a positive return on investment. Conclusion Reductions in injuries and associated costs were observed following implementation of a limited number of specific RM interventions.

The U.S. regulatory state overseeing worker safety has become more complex over time. We study the underground coal mining industry, where the Mine Safety and Health Administration and related laws have established a complex structure which mines must follow. In this sector, since 2000, both productivity and accident rates have dropped substantially, while regulatory inspections and fines have increased dramatically. We seek to estimate the marginal tradeoffs between productivity and safety imposed by the regulatory state. We use the occurrence of disasters near a mine and of fatalities at a mine as shocks that increase the costs of future accidents. We find that in the second year after a disaster, productivity decreases 11% and accident rates decrease 17-83% for mines in the same state as the disaster, with some evidence that the number of managers increases. After a fatality at a mine, government inspections and penalties increase and the rates of less-severe accidents decrease 14%, with no significant effect on severe accidents or productivity. Using published “value of statistical life” (VSL) and injury cost estimates, we find that the productivity loss following a disaster in the same state as a mine costs 2.7 times the value of the safety increases, implying that the regulatory state trades off productivity for safety at a much higher rate than would a VSL-based cost-benefit approach.

Metallized Teflon® fluorinated ethylene propylene (FEP) thermal control material on the Hubble Space Telescope (HST) is degrading in the space environment. Teflon® FEP insulation was retrieved during servicing missions, which occurred in 1993, 1997 and 1999. During the second servicing mission (SM2), the 5 mil aluminized-FEP (Al-FEP) outer layer of multilayer insulation (MLI) covering the telescope was found to be cracked in many locations around the telescope. Teflon® FEP retrieved during SM2 was more embrittled than the FEP retrieved 2.8 years later from a different location, during the third servicing mission (SM3A). Studies have been conducted to understand the degradation of FEP on HST, and the difference in the degree of degradation of FEP from each of the servicing missions. The retrieved SM2 material experienced a higher temperature extreme during thermal cycling (200 °C) than the first servicing mission (SM1) and SM3A materials (upper temperature of 50 °C), therefore an investigation on the effects of heating FEP was also conducted. Samples of pristine FEP and SM1, SM2 and SM3A retrieved FEP were heated to 200 °C and evaluated for changes in properties. Heating at 130 °C was also investigated because FEP bi-stem thermal shields are expected to cycle to a maximum temperature of 130 °C on-orbit. Tensile, density, x-ray diffraction crystallinity and differential scanning calorimetry data were evaluated. It was found that heating pristine FEP caused an increase in the density and practically no change in tensile properties. However, when as-retrieved space samples were heated, the density increased and the tensile properties decreased. Upon heating, all samples experienced an increase in crystallinity, with larger increases in the space-exposed FEP. These results indicate that irradiation of FEP in space causes chain scission, resulting in embrittlement, and that excessive heating allows increased mobility of space-environment-induced scissioned chains. Thermal exposure was therefore found to have a major impact on the extent of embrittlement of FEP on HST.

During the Hubble Space Telescope (HST) second servicing mission (SM2), degradation of unsupported Teflon® FEP (fluorinated ethylene propylene), used as the outer layer of the multilayer insulation (MLI) blankets, was evident as large cracks on the telescope light shield. A sample of the degraded outer layer was retrieved during the mission and returned to Earth for ground testing and evaluation. The results of the Teflon® FEP sample evaluation and additional testing of pristine Teflon® FEP led the investigative team to theorize that the HST damage was caused by thermal cycling with deep-layer damage from electron and proton radiation which allowed the propagation of cracks along stress concentrations, and that the damage increased with the combined total dose of electrons, protons, ultraviolet and x-ray radiation along with thermal cycling. This paper discusses the testing and evaluation of the retrieved Teflon® FEP.

Abstract The new generation of offshore support vessels (OSVs) has become increasinglysophisticated and technically advanced in response to demands from deepwaterdrilling and production operations. This paper reviews design issues and trendsfor the development of the next generation of OSVs, highlighting recentlyenhanced classification technical requirements. The new requirements addresssafety criteria and environmental protection for the design, construction andoperation of OSVs. The paper also includes applicable criteria and new notations for eachspecialized service of the OSV including transportation of supplies andequipment, towing and anchoring of offshore structures, well stimulation andtesting, fire fighting, heavy lift, oil spill containment, pipelineinstallation, diving activities and safety stand-by as well as provisions forthe integration of multifunctional services. Additionally, the paper addresses the use of LNG as a fuel for propulsionprimarily to reduce emissions. Introduction Over the years, Offshore Support Vessels (OSVs) have evolved dramatically asshown in Table 1 in terms of diversification, worldwide operation and waterdepth capabilities. This evolution of technology advancement has been driven bythe need to meet the ever-increasing support demands of deepwater drilling, production and subsea operations.

As NASA's next major space X-ray observatory, the Constellation-X mission (Bookbinder et al. 2008) requires mirror assemblies with unprecedented characteristics that cannot be provided by existing optical technologies. In the past several years, the project has supported a vigorous mirror technology development program. This program includes the fabrication of lightweight mirror segments by slumping commercially available thin glass sheets, the support and mounting of these thin mirror segments for accurate metrology, the mounting and attachment of these mirror segments for the purpose of X-ray tests, and development of methods for aligning and integrating these mirror segments into mirror assemblies. This paper describes our efforts and developments in these areas.