For giving the economic profits earned by every market participants through maintaining the security and reliability of power system,this paper proposes the concept of the economic equivalent of security measure.

The economic equivalent of security and reliability measure is based on the difference of the economic profits brought by the security and reliability measure and the cost needed by the implementation of the security measure.

Experimental study on equivalent density of rigid colloid foam drilling fluid and theoretical computation results show that when pressure, temperature, cuttings and circulating pressure loss are considered, the actual equivalent density is bigger than the base solution when the density of the base solution is 1.

A IG541 fire suppression laboratory and a equivalent length of pipe fittings measuring system were established.

This paper based on the example, the variable section step-shaft with spline or slot, and according to equal rigidity condition, Presenting calculable formula of equivalent length in accordance with the shaft under torsional working condition.

The model of equivalent length, the feasibility of the evacuation route and the concepts of the coefficient of pass difficulty, ease and danger were put forward.

The adhesive property of resorcin-formaldehyde (RF) resin was predicted indirectly by on-line measuring the equivalent viscosity of the solution of RF resin.

This paper has predicted indirectly by means of measuring the equivalent viscosity of resorcin-formaldehyde resin liquor(thereinafter referred to as RF resin).