درخت حوزه‌های تخصصی

The purpose of this study is to investigate the effect of competitive advantage strategies on customer loyalty with the mediating role of customers brand identification and brand awareness in the insurance industry. The study methodology is descriptive-correlational and the statistical population were Parsian Insurance brand customers in Rasht, Lahijan and Bandar Anzali cities. By the use of Morgan table, the sample size were 384 people which finally we selected 389 people by the use of random sampling method. The main dimensions of the research questionnaires were competitive strategies of differentiation, cost leadership, brand identification, brand awareness and customer loyalty. In order to analysis the data we used SPSS 22 and Smart PLS 2 software. The results indicated that differentiation strategies has meaningful and significant effect on customer loyalty and also the mediating roles of brand identity in the relationship between differentiation and customer loyalty and also in the relationship between cost leadership and customer loyalty were confirmed, but the relationship between cost leadership on customers loyalty and the mediating role of brand awareness in the relationship between differentiation on customer loyalty and cost leadership on customer loyalty were not confirmed. 

We have a huge civic project, includes several sub-projects, which are divided into activities. This project is a project to rehabilitate 550,000 hectares of agricultural land in the provinces of Khuzestan and Ilam. The project has been divided according to the plots of land. The Jehad in Tehran is managing the projects. They need project scheduling as well as resource levelling and "lot-sizing". Levelling and lot sizing are the most important issues in utilizing the limited resources. For determining the scope and the size of those sub-projects as well as their parallel activities, so far, many models have been proposed. However, the models are weak either in higher resource utilization or in solving numerically the problems. In this paper, our effort has been concentrated on developing scheduling, resource levelling, and lot sizing model, based on balancing utilization of resources, so that the real size civil project could be solved within an acceptable duration time. This paper proposes a goal programming linear model for simultaneous project scheduling and resource levelling. This model determines the best schedule of sub-activities (optimal "lot size" of each sub-activity) to reach the minimum amount of diversion of resources consumed from the number of resources available for the entire periods of the planning horizon. In fact, if the best "lot sizes" have been taken, then minimum fluctuation of the active resources is reached. The proposed model has been used to schedule a project with 87 activities. This project has been scheduled and, accordingly, the optimal volume (the "lot size") of sub-activities have been determined for each activity at any period of time. In this way, only 4 resources out of a total of 32 resources are in shortage. In contrast, the scheduling of this project, using the CPM, results in a shortage of 13 resources.