StretchArms: Promoting Stretching Exercise with a Smartwatch

A smartwatch is a wearable computer equipped with sensors. It can be used to provide fitness- or healthcare-related functionalities. This article presents three versions of a smartwatch application for prompting a user to stretch during the user’s daily life. The first version just reminds periodically the user that it is time to stretch and then guides the stretching motion. In contrast, the second version evaluates how correctly the stretching motion is made and provides success/fail feedback for the user. The third version adds gamification elements to the second version. With these three versions, an elaborate user study was performed with 42 participants. The results show that the reminders were effective in relaxing the mental/muscular tension of the users and the motion evaluation feedback encouraged the users to stretch more. In contrast, the effectiveness of gamification was not proven. This is the first study to prompt stretching exercise and evaluate it with a smartwatch. It can help develop effective healthcare applications on wearable devices.     

Estimation of the saw-tooth shock wave using a lead shock programmer

Structure durability under shock load is evaluated by performing a shock resistance test. Saw-tooth shock wave is generated in a specific environment and transmitted to the structure. The saw-tooth shock wave is generated using a specific impact test system. In general, the impact test system is generally composed of three types: Drop, lateral and rotational. Each type of impact test system has different detail parts. This study applies the drop-type impact test system. A test table, a fixed table, and a shock programmer compose comprise the drop-type impact test system. The drop-type impact test system uses the initial height of the test table, where the specimen is mounted on. The impact velocity in the drop-type impact test is determined by the initial height of the test table. The shock programmer generates the shock wave transmitted to the specimen mounted on the test table, which is then. The shock wave transmitted to the specimen is then generated by the shock programmer material. Parameter research of the parameter testing on the shock programmer has to be performed using the drop-type impact test system to generate the saw-tooth shock wave with non-linear characteristics. This study generates the saw-tooth shock wave by designing and simulating the lead shock programmer. Lead is considered as the shock programmer material. The accuracy of the simulation program (i.e., LS-Dyna) is verified by performing the drop shock test of theon the three types of lead shock programmer with three types. The results of the time history on the test table acceleration between the simulation and the test are compared with those of the shock test and the simulation. The shock test and simulation results are plotted using the tolerance range of the saw-tooth shock wave presented in MIL-STD-810G. The saw-tooth shock wave generated using the lead shock programmer with conical and truncated conical shape is estimated using the verified simulation program. The aspect ratio of the conical and truncated conical lead shock programmer is presented to generate the saw-tooth shock wave is also presented.

     

Public trust in a mobile device and service policy in South Korea: The Mobile Device Distribution Improvement Act

South Korea has the highest expenditure on telecommunications among OECD countries, drawing national attention to the issue of reducing high prices. In response, the Korean government enacted the Mobile Device Distribution Improvement (MDDI) Act to eliminate information asymmetry by limiting mobile carriers’ mobile handset subsidies to consumers. This study examined factors affecting public trust in the MDDI based by analyzing responses to a questionnaire survey using the ordered probit model. The results show that the knowledge, expectations, and perceived effects of the MDDI have a meaningful effect on public trust in the policy. The results of this study confirm that it is essential for governments to promote their policies by continuously educating the public, especially in this case because the policy has a direct effect on telecommunications expenditures.