The article presents the calculation and modeling of heat mass transfer that determines operating modes pumps. physical mathematical simulation aims at operation geothermal It is shown numerical main mechanisms affecting efficiency ground collection are little used for practical calculations in design pump systems. use results limited by specific geographical climatic conditions do not allow ge...

Sustainability certifications like BREEAM, LEED, and China's sustainable green building award certification scheme encourage installation of technologies that save mains water grid electricity. Among these are rainwater harvesting systems, ultralow use appliances, photovoltaic panel intelligent management systems. In reviewing the performance two award-winning university buildings over respecti...

utilizing the gathered failure data and failure interval data from tabas coal mine in two years, this paper discusses the reliability of powered supports. the data sets were investigated using statistical procedures and in two levels: the existence of trend and serial correlation. the results show that the powered supports follow the gamma reliability function. the reliability of the machine de...

The frequency-tuning and -control properties of monolithic doubly resonant optical parametric oscillators are analyzed for stable single-mode pump radiation. Single-axial-mode operation is observed on the idler and the signal for both pulsed and continuous pumping. Projections are made for tuning-parameter tolerances that are required for maintenance of stable single-frequency oscillation. Cont...

abstract while computerized maintenance management system (cmms) enables maintenance managers and supervisors to access information about equipment, manpower and maintenance policies, there is still a need to facilitate getting data/information into the backend database where it can be utilized by the organization as information to make decisions regarding the operation of the organization. sig...

in this paper we focus on a continuously deteriorating two units series equipment which its failure can not be measured by cost criterion. for these types of systems avoiding failure during the actual operation of the system is extremely important. in this paper we determine inspection periods and maintenance policy in such a way that failure probability is limited to a pre-specified value and ...

Hydraulic fracturing is used in the oil industry in order to increase the index of production and processing in the wells whose efficiencies have been dropped due to a long-term harvest or the rocks around the wells are of low permeability. Since the hydraulic fracturing operation is costly, it is of special importance to the project managers to determine the pressure required for hydraulic fra...

To explore the effectiveness of using flipped classroom approach, a group of 40 male 10th graders in the city of Babol, selected randomly through cluster sampling, was assigned to two classes one of which was taught using the said approach while in the other the traditional method was implemented. Both groups were pre- and post-tested on computer self-efficacy and classroom perception and then ...