Evaluation of a strain-gage load calibration on a low-aspect-ratio wing structure at elevated temperature

The environmental aspect of elevated temperature and its relationship to the science of strain gage calibrations of aircraft structures are addressed. A section of a wing designed for a high-speed aircraft structure was used to study this problem. This structure was instrumented with strain gages calibrated at both elevated and room temperatures. Load equations derived from a high-temperature load calibration were compared with equations derived from an identical load calibration at room temperature. The implications of the high temperature load calibration were studied from the viewpoint of applicability and necessity. Load equations derived from the room temperature load calibration resulted in generally lower equation standard errors than equations derived from the elevated temperature load calibration. A distributed load was applied to the structure at elevated temperature and strain gage outputs were measured. This applied load was then calculated using equations derived from both the room temperature and elevated temperature calibration data. It was found that no significant differences between the two equation systems existed in terms of computing this applied distributed load, as long as the thermal shifts resulting from thermal stresses could be identified. This identification requires a heating of the structure. Therefore, it is concluded that for this structure, a high temperature load calibration is not required. However, a heating of the structure is required to determine thermal shifts

Rebuilding a community: lessons from New Orleans

Whether low-income communities are struggling to rebuild after a hurricane or after long neglect, the challenges often seem insurmountable. The New Orleans 9th Ward’s inclusive approach to decision making shows that the best revitalization plans are those with the broadest buy-in.Community development

The supermarket revolution in developing countries: Policies for "competitiveness with inclusiveness"

"A “supermarket revolution” has been underway in developing countries since the early 1990s. Supermarkets (here referring to all modern retail, which includes chain stores of various formats such as supermarkets, hypermarkets, and convenience and neighborhood stores) have now gone well beyond the initial upper- and middle-class clientele in many countries to reach the mass market. Within the food system, the effects of this trend touch not only traditional retailers, but also the wholesale, processing, and farm sectors. The supermarket revolution is a “two-edged sword.” On the one hand, it can lower food prices for consumers and create opportunities for farmers and processors to gain access to quality-differentiated food markets and raise incomes. On the other hand, it can create challenges for small retailers, farmers, and processors who are not equipped to meet the new competition and requirements from supermarkets. Developing-country governments can put in place a number of policies to help both traditional retailers and small farmers pursue “competitiveness with inclusiveness” in the era of the supermarket revolution. Some countries are already taking such steps, and their experiences offer lessons for others." from Author's textSupermarkets, Wholesalers, Modern retail, Small farmers, Traditional retail, Supply chains, Competitiveness, Inclusiveness,

THE RISE OF KENYAN SUPERMARKETS AND THE EVOLUTION OF THEIR FRESH FRUITS AND VEGETABLES PROCUREMENT SYSTEMS

Supermarkets are rapidly penetrating urban food retail in Kenya and spreading well beyond their initial tiny market niche into the food markets of lower-income groups. Having penetrated processed and staple food markets much earlier and faster than fresh foods, they have recently begun to make inroads into the fresh fruits and vegetables category. The important changes in their procurement systems bring significant opportunities and challenges for small farmers, and have implications for agricultural diversification and rural development programmes and policies.Marketing,