to effectively design daylight in buildings, daylight availability data are necessary. although there is a great potential for daylight energy in iran, its use has been hampered by the absence of measured data. in this paper the illuminance data on the vertical south facing surfaces of tehran were estimated using the iesna model. for this propose an illuminance measuring set was used in order t...

The availability offered by current data replication and update algorithms varies with dynamically changing conditions which include the network configuration and system load. With dynamic adaptability, systems can switch to an appropriate mechanism to improve perFormance and availability, In this paper, we present an algorithm to estimate the overall availability of transaction processing in a...

The binary states, i.e., success or failed state assumptions used in conventional reliability are inappropriate for reliability analysis of complex industrial systems due to lack of sufficient probabilistic information. For large complex systems, the uncertainty of each individual parameter enhances the uncertainty of the system reliability. In this paper, the concept of fuzzy reliability...

This paper deals with the Markov modeling and reliability analysis of urea synthesis system of a fertilizer plant. This system was modeled using Markov birth–death process with the assumption that the failure and repair rates of each subsystem follow exponential distribution. The first-order Chapman–Kolmogorov differential equations are developed with the use of mnemonic rule and these equation...

Prognostics and Health Management (PHM) methods are incorporated into systems for the purpose of avoiding unanticipated failures that can impact system safety, result in additional life cycle cost, and/or adversely affect the availability of the system. Availability is the probability that a system will be able to function when called upon to do so. Availability depends on the system’s reliabil...

the impact of the international sanctions on the central bank of iran in 2013 and also accessibility of medicines in this country have received a lot of media coverage. in this study we used the data collected from a group of pharmacies all located in tehran to assess the potential effects of the banking sanctions on access to asthma medicines. data were collected from forty community pharmacie...

in order to improve the level of intelligence, availability, being on demand, convenience, information and humanization of rural public transportation systems, they are more willing to use modern information and communicative technologies. in addition to management services, intelligent transportation systems can provide passengers, drivers, travel agencies and other institutions with other ser...