Inside fire perimeters, large expanses of forest were completely untouched. The inmates remained static within the barbed wire perimeters. Electric fences have also proven successful as a means to secure perimeters from bear incursions. Steps outside the designated perimeters of the floor incur deductions. This minimizes the effect by filling the black pixel perimeters with adjacent light. By calculating the perimeters of these polygons, he proved that (that is ). There were also guard towers that surrounded the perimeters. They set up defensive perimeters around their respective missions. Physical port security involves the risks to the perimeters of the port. This indicates that the nodes will likely have small area and small perimeters. There are 23 wards situated within the perimeters of Glasgow City Council. There are several active beaver colonies within the park's perimeters. Today, strategic-use towers are still used at prisons, military camps, and defensive perimeters. However, names of barrios and districts do not necessarily coincide with barangay perimeters. Like the branching structure, this also has its set perimeters.