2021, Vol.7, No.4

Journal of Internet of Things and Convergence 2023 KCI Impact Factor : 0.89

pISSN : 2466-0078
https://journal.kci.go.kr/kiots

Recently, technological differentiation(sensor, AI) of products using IoT technology to satisfy consumer needs in the mature market for smart home appliances has received a lot of positive responses. However, air conditioner products are in the early stages of convergence technology. Therefore, air conditioner products are fields that require ICT technologies for information production, collection, processing, storage, and service development beyond IoT. In this paper, we collect and store contactless bio-signal using IR-UWB radar technology. The blowing direction of the air conditioning is controlled according to bio-signal and user's sleep is monitored to provide an optimal sleep environment. In addition, we propose a service algorithm that can provide comfort with changes in the optimal conditions of air conditioning and emotional lighting depending on the discomfort index environment. Through this study, we developed an intelligent smart air conditioning service platform with ICT technology of bio-signal, discomfort index, and emotional lighting.

In computing systems that require high reliability, the method of predicting the lifetime of a storage device is one of the important factors for system management because it can maximize usability as well as data protection. The life of a solid state drive (SSD) that has recently been used as a storage device in several storage systems is linked to the life of the NAND flash memory that constitutes it. Therefore, in a storage system configured using an SSD, a method of accurately and efficiently predicting the lifespan of a NAND flash memory is required. In this paper, a method for optimizing the lifetime prediction of a flash memory-based storage device using the frequency of NAND flash memory failure is proposed. For this, we design a cost matrix to collect the frequency of defects that occur when processing data in units of Drive Writes Per Day (DWPD). In addition, a method of predicting the remaining cost to the slope where the life-long finish occurs using the Gradient Descent method is proposed. Finally, we proved the excellence of the proposed idea when any defect occurs with simulation.

This study aims to derive the problems of firefighting and safety measures for architectural heritage with a wooden structure in rural areas and present their improvement measures. To identify those problems, this study grasped the features of the cultural heritage through the building structure and environment of a wooden Catholic secondary station in Dangjin, and analyzed fires that may occur and safety factors. As a result, although the mission station is an important cultural property in terms of its history, place and local identity, it had problems with disaster prevention systems such as vulnerable safety including fire and difficulties in fire recognition and initial firefighting. Therefore, this study concluded through its review and analysis that a disaster prevention system such as stronger firefighting is needed; that fire fighting facilities suitable for the characteristics of the secondary station with a wooden structure should be installed and a main player should be arranged in fire prevention activities to improve the fire prevention system of the cultural property; and that as most mission stations are located in rural areas, it is necessary to more thoroughly protect wooden-structure secondary stations from natural disasters such as forest fire and to improve fire response measures.