When playing scales on the piano, playing all notes evenly is a basic technique to improve the quality of music. However, it is difficult for beginners to do this because they need to achieve appropriate muscle synergies of the forearm and shoulder muscles, i.e., pressing keys as well as sliding their hands sideways. In this paper, we propose a system using electrical muscle stimulation (EMS) to teach beginners how to improve their muscle synergies while playing scales. We focus on “thumb-under” method and assist with it by applying EMS to the deltoid muscle. We conducted a user study to investigate whether our EMS-based system can help beginners learn new muscle synergies in playing ascending scales. We divided the participants into two groups: an experimental group that practiced with EMS and a control group that practiced without EMS. The results showed that practicing with EMS was more effective in improving the evenness of scales than without EMS and that the muscle synergies changed after practicing.

Since more and more devices are now network connectable, a user can enjoy one service on two or more devices. For example, a smart phone is used to operate the TV, or move a game currently displayed on the TV to the same smart phone, and continue playing the game. In order to realize these transferable services, developers must control communication between multiple devices. This greatly increases the development costs compared to single screen web applications. Factors include increases in code quantity and skill demanded from the developers. In this paper, we propose a framework that greatly simplifies the development of multi-screen web applications with JavaScript. We prototype the framework, and compare the proposal to an existing approach in terms of development cost. The results show that our framework allows developers to build multi-screen web applications with much less effort and time than the existing framework.

In this article, we propose a navigation system that interests users in contents, based on information on Web site visits and usage. The system guides users to tourist spots by applying a referral system. In cooperation with travel agencies, we verified the system by opening it to Internet access. Moreover, we extend the system to resolve the problems identified in the evaluation results.