ABSTRACT Considering the concept of quality of life in cities to be the same, urban planners do not have a precise understanding of the factors affecting the quality of life. Therefore, according to the size of the city, different indicators should be considered to measure the quality of life. Thus, according to the main goal of the research, which is to recognize, identify and compile the factors affecting the improvement of the quality of life in middle and small cities on an intra-provincial scale, Qazvin and Zia Abad cities in Qazvin province were selected as study samples. In order to achieve the goal of the research, exploratory factor analysis and regression analysis were exerted. The findings show that the homogenization of the indicators affecting the quality of life in all cities is incorrect. Some concepts, such as the size of the city, are effective in compiling and selecting the indicators affecting the quality of life. So, the indicators affecting the quality of life in each city can be different according to some concepts, such as the city's characteristics or the city's size. Examining study samples also shows that in small cities, social indicators are more important due to strong social solidarity among people and the high importance of social and cultural concepts. Moreover, in middle cities, due to the importance of finding economic concepts and urban services in people's lives and people's less communication with each other and the weakening of solidarity and social connections, indicators of urban services and facilities and economic factors have the most importance in explaining the quality of life; this shows that the Quality of life indicators are different in all cities Extended Abstract Introduction Quality of life is a multifaceted and dynamic concept that can be different from city to city and region to region and can be defined by various indicators. Not paying attention to this issue and considering the concept of quality of life equally in all cities has caused the level of quality of life to decrease in many cities, especially middle and small cities, in recent years. On the other hand, considering the concept of quality of life in cities to be the same, urban planners do not have a precise understanding of the factors affecting the quality of life. Following this, the main goal of this research is to identify, identify and compile effective factors for improving the quality of life in middle and small cities on an intra-provincial scale. In order to achieve this goal, the cities of Qazvin and Zia Abad in Qazvin province were selected as study samples, so that according to the size of the city, in order to achieve the goal of the research, the factors affecting the quality of life are analyzed on an intra-provincial scale.   Methodology The research method is applied research based on quantitative methods. In line with data analysis, after extracting 60 indicators of quality of life, first, the indicators were separated into separate and structured factors using the exploratory factor analysis method in SPSS software. And then, step by step regression method was used to measure the effective factors in improving the quality of life in cities.   Results and discussion The research findings show that based on exploratory factor analysis, 16 factors were extracted in Zia Abad city and 15 factors in Qazvin city as effective factors on the quality of life in small and middle cities. In order to present and explain the factors affecting the improvement of the quality of life in small and middle cities, the factors extracted from the factor analysis were analyzed by multivariate regression method and step-by-step method. Furthermore, finally, (13) factors were introduced in Zia   Abad and (13) factors in Qazvin as the main factors influencing the quality of life. The analysis of the findings indicates that in Zia Abad, factors such as life expectancy and social relations, security, the state of urban services and access to urban facilities, living expenses, the state of urban furniture, urban traffic, the state of offices and housing have more effects in explaining and improving the quality of life. In Qazvin, factors such as the state of urban services, the state of green and public spaces in the city, the state of security and economic opportunities in the city, the density and hope of urban, economic, and cultural life, the state of roads and leisure in the city are effective in explaining the quality of life. Following this, according to the above findings, quality of life is a multidimensional and dynamic concept that directly relates to the type of cities and the specific characteristics of cities. Therefore, the quality of life and its indicators can differ from city to city; because every city has its characteristics and characteristics with citizens with different cultures and thinking, which causes the factors affecting the quality of life to be different. Therefore, considering the quality of life and its indicators to be the same in all cities is wrong, which can lead to the decline of the quality of life and the failure of quality of life improvement programs.   Conclusion Finally, the research results indicate that quality of life is a simple concept covering various urban life aspects. This concept can be defined as a determining factor in the excellence and progress of cities and residents' satisfaction with their urban life. It is multifaceted and dependent on place and time. As a result, the perception of people in different cities and communities about the concept of quality of life and the factors affecting it can be different. Following this, factors and indicators should be selected according to the characteristics and conditions of that city in urban planning to improve the quality of life for each city. Thus, this research, using the classification of cities based on the size of the city, has presented factors specifically for middle and small cities, which in small cities due to strong social solidarity among people and the great importance of social and cultural concepts, social indicators are more important. Moreover, in middle cities, due to the importance of finding economic concepts and urban services in people's lives and people's less communication with each other and the weakening of solidarity and social connections, indicators of urban services and facilities and economic factors have the most importance in explaining the quality of life; this shows that the quality of life indicators are different in all cities.   Funding There is no funding support.   Authors’ Contribution All of the authors approved the content of the manuscript and agreed on all aspects of the work.   Conflict of Interest Authors declared no conflict of interest.   Acknowledgments We are grateful to all the scientific.

Nowadays, one of the intractable challenges facing the minerals industry is the processing of complex ores. Processing of high sulphur content ore type is a major challenge in iron ore beneficiation. Thus, modification of mineral processing circuits to process iron ore with high sulphur content is essential. In this research, employing a regrinding section in iron ore concentrator aiming to reduce the particle size and improve the quality of concentrate in Golegohar concentrator line no. 4 was investigated. In this order, two different configurations were studied including regrind mill after high intensity (rougher, cobber) and low intensity (recleaner) magnetic separators. To assess the results of the circuit configurations, iron and sulphur grade, yield and blaine of concentrate were considered. Furthermore, the effect of particle size fractions with the d80 of 38, 45, 63 and 80 μ m in the configurations was evaluated to find optimum particle size. Results indicated that the desired particle size in the reduction of sulphur content is +63-80 μ m. Furthermore, utilising regrind mill after cobber resulted in a higher iron grade, yield and blaine while lower sulphur grade was attained with the regrinding after recleaner.