RESUMO
Solar energy is the most sustainable and free source to manage the world energy demand. One aspect of solar-driven energy supply can be observed in cooling systems. Recently, solar energy-based cooling systems have received many attentions. Solar cooling systems utilizing solar collectors, as the renewable and sustainable-based solution, have the good potentials to overcome the challenges associated with consumption of fossil fuels. In this study, the recent advances about the potentials of dish collectors and linear Fresnel reflectors for the usage in the cooling systems are reviewed. In addition, the solar-powered conventional absorption chiller and cryogenic systems are investigated. Hybrid cooling solar systems and solar-based combined cooling, heating, and power systems are also studied. The hydrogen production in cooling integrated systems and cold thermal energy storage are discussed. In each section, in addition to general description of the system, some explanations about the thermodynamic and economic aspects of the systems are provided. Finally, the main results of the review are summarized and based on the available gaps between the literatures, some suggestions are provided for the future studies. It was found that using solar dish collectors in a hybrid system, designed for the freshwater and LNG production, causes carbon dioxide emissions reduction by 40%, and also increases freshwater and LNG production by 95% and 4.7%, respectively. In the hybrid trigeneration solar-biomass power plants, using the linear Fresnel reflector leads to 29% save in biomass and land.
Assuntos
Energia Solar , Combustíveis Fósseis , Calefação , Temperatura Alta , Luz SolarRESUMO
BACKGROUND: Health worker motivation has the potential to have a large impact on health system performance, and this depends on some factors. The purpose of this study was to determine the factors affecting this motivation. METHODS: From Winter 2013 to Spring 2014, 1046 employees and physicians (439 males and 607 females) with a mean age of 36 and 37.2 years in men and women, respectively were chosen in selected hospitals of Social Security Organization (SSO). They were randomly categorized into six different classes of service record, age education class of hiring (permanent and contractual), marital status, and gender. The variables assessed via the classification groups were as follows: interpersonal relations, working conditions, equity, pay, job security, supervision, advancement, recognition, responsibility, and attractiveness of job, educational and organizational policies. RESULTS: Bachelor's degree (65%) or higher were the education degrees of most participants. Significant relations were observed regarding age, marital status, hiring, gender and years of service with promotion, recognition, responsibility, attractiveness of job, education, relations, working condition, equity, salary, job security, supervision and organizational policies. There were significant relations with hire status and degree with advancement and other variables. There were significant relations between marital status, gender, years of service and age with the above variables. CONCLUSION: The results show that the important variables that influence motivational factors are academic degree, hire status, marital status, gender, age and years of service.
RESUMO
BACKGROUND: Patient satisfaction is affected by hospital services and may have an effect on the cultural, social and personal conditions of the people living in the region. This research aimed to evaluate the patient satisfaction in social security hospitals in Mazandaran province. METHODS: From Spring 2012 to Summer 2013, all patients admitted to social security hospitals in Mazandaran province were entered in the study. Data regarding to inhabitation, sex, income and patients' educational level and satisfaction with the hospital services were collected. RESULTS: Seven hundred seventy-six patients with mean age of 47.35±7.41 years were analyzed. Patient's inhabitant, educational attainment and income level had a significant relationship with patient satisfaction level (p<0.05). There was no significant difference regarding patients' gender. CONCLUSION: The results show that the patient's inhabitant, educational and income level are related to attain patients' satisfaction.
RESUMO
BACKGROUND: A nurse's commitment is the most important factor that influences her performance and depends on other variables. The purpose of this research was to study the relationship between length of service of the nurses with the amount of occupational commitment and organizational commitment. METHODS: From Winter 2012 to Spring 2013, 266 nurses were chosen in selected hospitals of Social Security Organization (SSO). These nurses were randomly categorized into six different classes of service records including < 5, 5-9, 10-14, 15-19, 20-24, and 25-29 years. The length of service is related to the organizational, occupational, affective, continuance, and normative commitment. The data were collected and analyzed. RESULTS: Generally 84% of the responders were women and the rest were men of which 95% had a bachelor's degree and the rest had higher academic degrees. The length of service in 81% of nurses was <15 years and 19% were higher than 15 years. Significant correlation were seen between continuance and occupational commitments and length of service (r=0.23, P=0.04 and r=-0.26, P=0.02, respectively). There were not any significant differences regarding organizational, affective and normative commitments (P=0.12, P=0.33, P=0.47, respectively). CONCLUSION: The results show that the length of service was related to continuance and occupational commitment. So pre-retirement of the nurses after 20 years of work can result in an increase in average commitment of employees.
