Researchers believe that health foods can promote health and that the consumption of health foods can effectively help people to maintain their health. This study mainly adopted the health belief model (HBM) integrated with perceived behavioral control to investigate the repurchase behavior of consumers with regard to health foods that improve gastrointestinal functions. We obtained 550 valid questionnaires from consumers who had purchased gastrointestinal health foods and conducted structural equation modeling. Results from our analysis revealed that perceived susceptibility, perceived severity, perceived benefits of action, and perceived behavioral control exert a positive influence on repurchase intention and that perceived barriers of action exerts a negative influence on repurchase intention. Furthermore, repurchase intention was found to have a positive impact on repurchase behavior. The results of this study can be used as a reference for health food marketing strategies and public health behavior promotions.

The concept of the virtual power plants (VPPs) in smart grids is receiving a great deal of attention because of the following two potentials. One is that the virtual power plant can secure the power system by controlling the power for customers participating in the demand response program and the energy storage systems in order to maintain the power system operation. The other is that the virtual power plant can effectively integrate renewable energy sources (RESs) with the power system to increase the penetration level of RESs and provide different types of auxiliary services for system operations. Although the virtual power plant is of benefit to the power system, it would also be beneficial for VPPs operators to be able to quantify the earnable profit of such an operation. The aim of this paper is to present a methodology for determining the maximum profit for virtual power plants in liberalized electricity markets through optimal power flow by controlling the power for customers participating in the demand response program and the energy storage systems in the presence of RESs. With the proposed method, business owners can more effectively operate VPPs. The test results of a modified IEEE 37-node feeder test system are presented.