Development of Non-invasive Measurement Systems for Water Content on the Surface of Mural Paintings

为了防止颜料脱落、盐分沉积、真菌生长等，了解壁画表面的水分和蒸发情况是非常重要的。然而，由于高湿度环境下的非侵入性测量困难，目前的研究并不多，本研究首先利用两个小型数据记录器构建了一个测量系统。根据温度和相对湿度测量值计算出的绝对湿度梯度，可以确定石头表面的蒸发量。这种方法的缺点之一是数据记录仪的耐湿性较差。选择了抗湿性较好的温湿度传感器，开发了一种适用于潮湿地区的新型温湿度传感器。它由一块Arduino Mega 2560控制板组成，它控制来自传感器的数字信号，并将数据记录在Micro SD卡上。本研究对一个原型系统进行了评估。

It is important to understand the water content and evaporation on the surface of mural paintings in order to prevent from exfoliation of pigments, deposition of salts, fungi growth and so forth. However, there have not been many researches because non-invasive measurements in high-humidity environment are difficult.In this study, a measurement system was first constructed using two small data-loggers. Evaporation on the surface of the stone was identified from the gradient of absolute humidity calculated from measured values of temperature and relative humidity. One of the drawbacks of this method is that the data-logger is poor in humidity resistance. Temperature and humidity sensors, which have better humidity resistance, were selected to develop a new system for application at humid sites. It is composed of a control board Arduino Mega 2560, which controls the digital signals from sensors and records the data on a micro SD card. A prototype system was evaluated in this study.