PURPOSES : The number of snowfall and the amount of snowfall are gradually increasing, and due to the characteristics of Seoul, which has a lot of traffic, it is difficult to respond quickly with a snow removal method that relies on snow removal vehicles. Therefore, it is necessary to develop an IoT based eco-friendly snow removal system that can respond to unexpected heavy snow in winter. In this study, the low temperature operation and snow removal performance of the IoT road condition snow removal detector and the snow removal system using CNT and PCM are evaluated in the climatic environment chamber. METHODS : To make artificial snow, it consists of an climatic environment chamber that can simulate a low temperature environment and equipment that can supply compressed air and cold water. Depending on the usage characteristics of the climatic environment chamber, use an air-water type snow maker. In order to make artificial snow, wet temperature, which takes into account the actual air temperature and the amount of moisture in the air, acts as the most important variable and is suitable for making snow, below –1.5 ℃. The lower the water temperature, the easier it is to freeze, so the water source was continuously supplied at 0 ℃ to 4 ℃. One of the two different pipes is connected to the water tank to supply water, and the other pipe is connected to the compressor to supply high-pressure air. Water is dispersed by compressed air in the form of many small droplets. The sprayed microscopic water particles freeze quickly in the low temperature environmental climatic chamber air and naturally fall to the floor, forming snow. Based on the KS C IEC 60068-2-1 cold resistance test standard, an integrated environmental test procedure was prepared to apply to IoT-based snow removal systems and performance evaluation was performed accordingly. The IoT based eco-friendly snow removal system is needed to in winter, so visual check and inspect the operation at the climatic chamber before setting up it to the actual site. In addition, grid type equipment was manufactured for consistent and reliable snow removal performance evaluation under controlled environmental conditions. RESULTS : The IoT-based eco-friendly snow removal system normally carried out the task of acquiring data and images without damaging the appearance or freezing in a low temperature environment. It showed clear snow removal performance in areas where PCM and CNT heating technology were applied to the concrete slab. This experiment shows that normal snow removal tasks can be carried out in low temperature environments in winter. CONCLUSIONS : The integrated environmental test procedures and grid type evaluation equipment are applied to low temperature operation and snow removal performance evaluation of snow removal systems. In the climatic environment chamber, where low temperature environments can be simulated, artificial snow is created regardless of the season to derive quantitative experimental results on snow removal performance. PCM and CNT heating technology showed high snow removal performance. The system is expected to be applied to road site situations to preemptively respond to unexpected heavy snow in winter.

With the development of drone technology, drones are being used in various industries. In general, drones use lithium-based battery pack, which is sensitive to external impact and temperature characteristics. Therefore, in order to prevent this problem, a battery case for protecting the battery from the outside is used. Usually, carbon fiber is used as case material, carbon fiber is expensive and has disadvantages of being difficult to manufacture. In this study, a battery case was fabricated to minimize the influence of external impact and temperature by using expanded polypropylene material, and also the battery efficiency test was performed using fabricated case. After basic design for battery case was conducted, a system capable of maintaining temperature was constructed by attaching a surface heating element inside the case, and the effect of maintaining temperature according to the presence or absence of the case was confirmed. Using manufactured prototype case, flight tests were carried out to check the battery voltage level according to the presence or absence of the case and to analyze the effect of improving the battery efficiency for the flight time of the drone.

무스카리는 백합과의 단자엽식물로서 전세계에 약 50여종이 자생하고 있으며, 내한성이 강한 추식구근으로 지중해 연안과 중앙아시아 지역에 걸쳐 자생하고 있다. 주로 분화용이나 화단용으로 이용되며, 화색은 청색, 백색, 자주색이 있다. 우리나라에서는 번식은 주로 모구 의 기부에서 형성되는 자구를 분리하여 사용되고 있으나, 바이러스 감염, 모구의 비싼 가격, 대량번식의 어려움 등의 문제점이 있다. 따라 서 본 실험은 무스카리의 종자번식의 가능성을 알아보기 위해, 종자발아에 미치는 저온처리 및 발아에 필요한 온도와 광 조건에 대해 알아 보고자 실시하였다. 파종전 0과 15℃에서 15~90일까지 저온처리 후 20℃에서 파종한 결과 발아율이 0~6.7%로 매우 낮았다. 5와 10℃에 서는 저온 처리일수가 경과할수록 발아율이 높아졌는데, 5℃에서 75일과 90일처리는 파종전에 이미 각각 54%, 71%가 발아한 상태였고, 최종 발아율은 66.7%와 84.0%로 가장 높은 발아율을 보여 주었다. 5℃에서 70일간 저온처리 한 후 5, 10, 15, 20, 25, 30℃에서 파종하였는 데, 파종 전 발아율은 34%였고, 최종 발아율은 10℃에서 82.7%로 가장 높았고, 5와 15℃에서 각각 75.3%와 76.7%, 20~30℃에서는 48.0~58.0%로 나타났다. 그러나 50% 발아율까지의 일수는 15℃에서 4.7일로 가장 짧았으며, 10과 5℃에서 각각 18.7일, 28.3일로 길었 다. 따라서 무스카리 종자는 파종 전 5℃에서 75~90일간 저온처리한 후 10~15℃에서 파종하는 것이 발아율 향상에 효과적일 것으로 판단 되었다.