Quick Launch. The Navy Individual Ready Reserve (IRR) is a force that consists of personnel who must fulfill their MSO under 10 U.S.C., 651, members fulfilling a service obligation incurred via contract, and those who have fulfilled their MSO but voluntarily remain in the IRR.
E is the magnitude of the electrical field in the material (V/m), J is the magnitude of the electric current density in the material (A/m 2). If the electrical field (E) through a material is very large and the flow of current (J) very small, it means that the material has a high resistivity.
Insulation works by reducing the transfer of heat by means of a barrier. Unfortunately in most cases the better the insulation the more it costs, so like most things a balancing act is required. To understand insulation you need to know what thermal conductivity, R values and U values are. Thermal conductivity is the measure of how easily heat flows through a specific type of material, regardless of the thickness of the material. The lower the thermal conductivity of a material, the better the thermal performance (i.e. the slower heat will move across a material). See below for some example materials and there conductivity values.