Bosed on the actual operation of the transformer in a power plant,this paper analyzes and evaluates the economic performance,total operating costs(TOC)and investment payback period of upgraded S7 and SJ transformers by using total operating costs of transformer and provide reliable basis for the transformer economic operation and create more economic benefits for the enterprise.

Discusses the relative electric power consumption for the single and double pipe system using frequency control of the pumps, provides their values calculated for 18 cities in China and a formula to estimate the static payback period for actual systems and an example.

In order to study the influences of various factors on bacterial count recovered from moist tissue bacterial carrier,living bacterial count method was used to observe experimentally the factors such as the time of bacterial contamination of the moist tissue,degree of driness of bacterial carrier and slant culture condition.

The parameter recovery method used in program algorithm of Weibull diameterdistribution model s was described and computer program was designed using C language.