Abstract: A method of bovine herd management based upon a dynamic mathematical model. The method gathers data on milk production on a periodic or routine basis for each cow in the herd. The data includes factors denoting both the quantity and the quality of the milk being produced. A database for each cow is established and continuously updated. A mathematical herd management model is used to establish the database, wherein the gathered data is then modified and used to interpret and determine the actual productivity of each cow in the herd for that test day. Using this data, a manager of the herd can then breed those cows having a capability superior to their associates in the herd. Likewise, the less productive members of the herd can be culled or eliminated from the herd. Another aspect of the invention includes the use of the database to quantitatively assess the effect of change, including changes made in formulas, in environmental conditions and in breeding practices.

Abstract: An indoor gun firing range enclosure having an air supply plenum disposed at the uprange end wall of the enclosure and at least one air exhaust plenum located proximate the bullet trap located proximate the downrange end wall of the enclosure. The ceiling of the enclosure uniformly slopes downwardly from the uprange wall in a direction toward the downrange end wall of the enclosure. In an advantageous embodiment of the indoor gun firing range enclosure the air supply plenum is disposed at the intersection of the ceiling and uprange end wall and is designed to emit one-third of the air at an angle of approximately 45.degree. to the vertical and the remaining two-third portion of air in a downwardly direction.

Abstract: An indoor gun firing range enclosure with a ventilation system for removing particulate matter, such as lead or other heavy metals, and unburned gunpowder, plus gaseous contaminants such as carbon monoxide, from the atmosphere within the enclosure to make the atmosphere within the enclosure safer for persons using the firing range.In addition, a method of ventilating the indoor firing range enclosure for the same purpose.Both the ventilation system and method of ventilating contemplate removing a portion of the air from within the enclosure and after removing particulate matter from this air, exhausting it to the out-of-doors. Concurrently, another portion of the air is removed from the interior of the enclosure for recirculation into the enclosure after particulate matter is removed from it. Out-of-doors air is also mixed with the recirculated portion of the air to make up for some of the air exhausted from the enclosure to the out-of-doors.