A survey of laser lightning rod techniques

The work done to create a laser lightning rod (LLR) is discussed. Some ongoing research which has the potential for achieving an operational laser lightning rod for use in the protection of missile launch sites, launch vehicles, and other property is discussed. Because of the ease with which a laser beam can be steered into any cloud overhead, an LLR could be used to ascertain if there exists enough charge in the clouds to discharge to the ground as triggered lightning. This leads to the possibility of using LLRs to test clouds prior to launching missiles through the clouds or prior to flying aircraft through the clouds. LLRs could also be used to probe and discharge clouds before or during any hazardous ground operations. Thus, an operational LLR may be able to both detect such sub-critical electrical fields and effectively neutralize them

The weld-brazing metal joining process

Superior mechanical properties were obtained in metal joints weld-brazed between faying surfaces. Weld-braze applications and advantages are listed

Weld-brazing - a new joining process

A joining process designated weld brazing which combines resistance spot welding and brazing has been developed. Resistance spot welding is used to position and align the parts as well as to establish a suitable faying surface gap for brazing. Fabrication is then completed by capillary flow of the braze alloy into the joint. The process has been used successfully to fabricate Ti-6Al-4V titanium alloy joints using 3003 aluminum braze alloy. Test results obtained on single overlap and hat-stiffened structural specimens show that weld brazed joints are superior in tensile shear, stress rupture, fatigue, and buckling than joint fabricated by spotwelding or brazing. Another attractive feature of the process is that the brazed joints is hermetically sealed by the braze material

Dealing with Climate Change Under the National Environmental Policy Act

The National Environmental Policy Act (NEPA) was an important environmental law for several decades before climate change became an issue of concern. Beginning in the 1990s efforts began to include in NEPA’s environmental assessments and environmental impact statements both the impact of federal government actions on climate change and the impact of climate change on proposed federal actions. These efforts were encouraged by the Council on Environmental Quality. However, implementation at the agency level has been uneven. Some Federal agencies have resisted making serious efforts to incorporate climate change impacts into their decision-making process. Moreover, the courts have not been consistent in their reviews of agency compliance with NEPA, and the judiciary often give substantial deference to an agency’s minimal NEPA compliance. Since 2017, determining NEPA’s requirements for climate change analysis has become more challenging because the Trump Administration is changing federal environmental policies and regulations in order to encourage fossil fuel energy development and use, which will increase the emissions of greenhouse gases

Touching plantation memories : tourists and docents at the museum

Plantations are one of the long-standing symbols of the U.S. South. Today, almost four hundred former plantation sites are museums. Over the last fifteen years a sustained, critical consideration of how slavery is remembered at these sites has developed in the academic literature. Geographers have argued that remembering slavery at these sites is geographic not only because most of these sites are in the South, but also because the public spatializes memory in certain ways at these historic places. To date, much of the memory literature about plantation museums focuses on the roles of these museums and their staff in remembering, forgetting, minimizing, and misrepresenting plantation slavery. While tourists have not been ignored, less information has been developed about how they participate in remembering the past at historic sites associated with the plantation and slavery. Through their presence, written and spoken comments and questions, and other actions tourists influence the social process of remembering plantation slavery. To understand some of the ways that tourists shape how slavery is connected to the memory of a place, I analyzed postcards and participated in house tours with other tourists. I learned that while there are often efforts on the part of local stakeholders to frame a site’s connection to slavery in certain ways, visitors often transform these associations. In some cases, the associations between a place and slavery are shaped, in other cases, tourists participate in marginalizing the memory of enslaved people. Whether by postcard, things said or even the things within a plantation museum that they touch, tourists try to connect themselves to the past. The connections that visitors make are part of the process of remembering the past. Understanding tourists better is an important step towards a fuller remembering of slavery at historic sites like plantation house museums