With the evolution of technology, the maintenance of sophisticated systems is of concern for system engineers and system designers. The maintenance cost of the system depends in general on the replacement and repair policies. The system replacement may be in a strictly periodic fashion or on a random basis depending upon the maintenance policy. At failure, the repair of the system may be perfor...

in this paper, we focus on a continuously deteriorating critical equipment which its failure cannot be measured by cost criterion. for these types of systems like military systems, nuclear systems, etc it is extremely important to avoid failure during the actual operation of the system. in this paper we propose an approach which constrains failure probability to a pre-specified value. this valu...

Power systems should have acceptable reliability in order to operate properly. Highly available and dependable protective relays help to obtain the desirable reliability. The relays should be periodically evaluated during specific intervals to achieve the mentioned characteristics. The Routine Test Interval (RTI) should be optimized in order to economically maximize the reliability of the prote...

in this study a new minimum lumped electrical model of total circulatory system through numerical solutions to approximate the response of the human circulatory system was presented. among five existent ventricular elastances as activity function of heart pumps, a more accurate model was chosen as well as the operation of baroreflex system to accommodate variations in heart rate and systemic va...

background the transjugular intrahepatic portosystemic stent-shunt (tipss) builds a shortcut between the portal vein and a liver vein, and represents a sophisticated alternative to open surgery in the management of portal hypertension or its complications. objectives to describe clinical experiences with a low-profile nitinol stent system in tipss creation, and to assess primary and long-term s...

background chronic heart failure (chf) is associated with unpredictably increased prevalence of hospital admissions. self-care is one of the most important aspects of management for patients with chf. self-care adequacy has led to increased satisfaction, independence in daily activities, reduced stress, and morbidity. objectives we aimed to assess the relationship between self-care behavior and...

introduction:guillain-barre syndrome(gbs) is the most common cause of acute flaccid paralysis. respiratory failure is the most serious short-term complication of gbs and invasive mechanical ventilation is required in 30% of patients.moreover,60% of those who are intubated develop major complications including pnemonia,sepsis,gi bleeding and pulmonary embolism. thus respiratory failure predictio...