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This paper discussed the application of health monitoring systems to 20th-century historic buildings. Natural disasters are major threats to monuments. They are often seismically vulnerable and require interventions. However, taking into account their historic and cultural values, it is appropriate to observe long-term behaviour before making a decision on intervention schemes. To this aim, health monitoring is considered an effective approach. In recent years, MEMS (micro-electromechanical systems) accelerometers have been attracting attention for their convenience and efficacy. Nonetheless, the reliability of MEMS accelerometers still needs to be examined for the monitoring of monuments as sufficient research contributions have not been made. This paper presented two case studies that were monitored by means of MEMS accelerometers. They were masonry structures positioned in seismic-prone regions in Japan. A number of earthquakes were detected by the accelerometers during one year of monitoring. To examine the accuracy of the adopted MEMS accelerometers, dynamic identification tests were conducted using high-sensitivity strain-gauge accelerometers and servo velocity meters. Based on responses obtained from the tests, numerical simulation was performed. Nonlinear static analysis was performed. The numerical simulation permitted the comparison of reliability among sensors and test types. This paper provided suggestions for the dynamic identification tests of heritage structures.

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Amorphous carbon (a-C) based catalysts having higher oxygen reduction reaction (ORR) activity and higher stability for ORR were realized by inserting nitrogen atoms in the valleys of zigzag edges of sp 2 cluster surface in a-C. ORR activity could be controlled by varying sizes and volume density of sp 2 cluster. The maximum number of electrons of 2.82 for ORR was achieved. The N-doped a-C catalysts have the activity of 4-electron O2 reduction reaction. The catalytic activity was stable in long term (150 times) measurements. Consequently, the N-doped a-C catalysts possesss ly, imes) measurements higher stability for ORR.