• Journal of Platform Technology
• /
• v.8 no.4
• /
• pp.59-69
• /
• 2020

Recently, the seriousness of ultrafine dust and fine dust has emerged as a national disaster, but small and medium-sized cities in provincial areas lack fine dust monitoring stations compared to their area, making it difficult to manage fine dust. Although the computing resources for collecting and processing fine dust data are not large, it is necessary to utilize cloud and private and public data to share data. In this paper, we proposed a small edge computing system that can measure fine dust, ultrafine dust and temperature and humidity and process it to provide real-time control of fine dust and service to the public. Collecting fine dust data and using public and private data to service fine dust ratings is efficient to handle with edge computing using raspberry pie because the amount of data is not large and the processing load is not large. For the experiment, the experiment system was constructed using three sensors, raspberry pie and Thinkspeak, and the fine dust measurement was conducted in northern part of kyongbuk region. The results of the experiment confirmed the measured fine dust measurement results over time based on the GIS data of the private sector.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.21 no.1
• /
• pp.175-179
• /
• 2021

With the recent increase in the proportion of single-person households, the demand for reasonable personal mobility has increased, and the "Personal Mobility" industry that can be used conveniently and concisely has grown rapidly. In fact, according to data from the Korea Transport Institute, the scale of the electric kickboards rental industry, one of the personal mobility industry sectors, is expected to expand to 200,000 units in 2022. Due to the characteristics of electric kickboards that are powered by electricity, stable and efficient battery supply is the most basic and important issue. According to recent reviews from users who have used the electric kickboard, there were cases where the use of the electric kickboard is attempted, but the battery is in a discharged state or the battery charge level is low and thus cannot be used. Therefore, this paper proposes a solar charging system for stable battery use of electric kickboards. When this system is applied, it is expected that it will not only be an eco-friendly charging method for electric kickboards, but also stably supply and demand batteries while driving.

• Journal of Internet of Things and Convergence
• /
• v.9 no.1
• /
• pp.125-129
• /
• 2023

Age of Information (AoI) has been introduced in wireless networked control systems (WNCSs) to guarantee timely status updates. In addition, as the edge computing (EC) architecture has been deployed in NCS, EC close to sensors can be exploited to collect status updates from sensors and provide control decisions to actuators. However, when lots of sensors simultaneously deliver status updates, EC can be overloaded, which cannot satisfy the AoI requirement. To mitigate this problem, this paper uses actuators with computing capability that can directly receive the status updates from sensors and determine the control decision without the help of EC. To analyze the AoI of the actuation update via EC or directly using actuators, this paper developed an analytic model based on timing diagrams. Extensive simulation results are included to verify the analytic model and to show the AoI with various settings.

• Journal of Internet of Things and Convergence
• /
• v.10 no.2
• /
• pp.125-130
• /
• 2024

With the rapid growth of mobility technology, the industrial sector is demanding storage devices that can reliably process data from various equipment and sensors in vehicles. NAND flash memory is being utilized as a storage device in mobility environments because it has the advantages of low power and fast data processing speed as well as strong external shock resistance. However, flash memory is characterized by data corruption due to long-term exposure to high temperatures. Therefore, a dedicated system for temperature management is required in mobility environments where high temperature exposure due to weather or external heat sources such as solar radiation is frequent. This paper designs a dedicated temperature management system for managing storage device temperature in a mobility environment. The designed temperature management system is a hybrid of traditional air cooling and water cooling technologies. The cooling method is designed to operate adaptively according to the temperature of the storage device, and it is designed not to operate when the temperature step is low to improve energy efficiency. Finally, experiments were conducted to analyze the temperature difference between each cooling method and different heat dissipation materials, proving that the temperature management policy is effective in maintaining performance.

• Journal of Korea Society of Industrial Information Systems
• /
• v.29 no.4
• /
• pp.43-54
• /
• 2024

This study presented a cybersecurity risk management system in a smart factory environment. A smart factory refers to a factory that optimizes the production system and increases efficiency. However, this digitized environment is vulnerable to cyber attacks, and manufacturing companies can suffer serious damage from disruptions in production systems or information leaks. Therefore, a systematic approach to effectively managing cyber security risks is essential in smart factories. In this study, a continuous security risk management system for each stage of the smart factory was proposed along with business process-based security risk assessment. These studies will help to further improve cybersecurity risk management in smart factories. It will also play an important role in ensuring that smart factories operate safely and efficiently.

• Journal of Internet Computing and Services
• /
• v.21 no.4
• /
• pp.25-34
• /
• 2020

In the current medical information system, a system environment is constructed in which Biometric data generated by using IoT or medical equipment connected to a patient can be stored in a medical information server and monitored at the same time. Also, the patient's biometric data, medical information, and personal information after simple authentication using only the ID / PW via the mobile terminal of the medical staff are easily accessible. However, the method of accessing these medical information needs to be improved in the dimension of protecting patient's personal information, and provides a quick authentication system for first aid. In this paper, we implemented an automatic authentication system based on the patient's situation and evaluated its performance. Patient's situation was graded into normal and emergency situation, and the situation of the patient was determined in real time using incoming patient biometric data from the ward. If the patient's situation is an emergency, an emergency message including an emergency code is send to the mobile terminal of the medical staff, and they attempted automatic authentication to access the upper medical information of the patient. Automatic authentication is a combination of user authentication(ID/PW, emergency code) and mobile terminal authentication(medical staff's role, working hours, work location). After user authentication, mobile terminal authentication is proceeded automatically without additional intervention by medical staff. After completing all authentications, medical staffs get authorization according to the role of medical staffs and patient's situations, and can access to the patient's graded medical information and personal information through the mobile terminal. We protected the patient's medical information through limited medical information access by the medical staff according to the patient's situation, and provided an automatic authentication without additional intervention in an emergency situation. We performed performance evaluation to verify the performance of the implemented automatic authentication system.

• Journal of Internet Computing and Services
• /
• v.22 no.4
• /
• pp.83-98
• /
• 2021

The purpose of this study to find the factors influencing the fire alarms using IoT firefighting facility management system data of Seoul Fire & Disaster Headquarters, and to present academic implications for establishing an effective prevention system of fire situation. As the number of high and complex buildings increases and former bulidings are advanced, the fire detection facilities that can quickly respond to emergency situations are also increasing. However, if the accuracy of the fire situation is incorrectly detected and the accuracy is lowered, the inconvenience of the residents increases and the reliability decreases. Therefore, it is necessary to improve accuracy of the system through efficient inspection and the internal environment investigation of buildings. The purpose of this study is to find out that false detection may occur due to building characteristics such as usage or time, and to aim of emphasizing the need for efficient system inspection and controlling the internal environment. As a result, it is found that the size(total area) of the building had the greatest effect on the fire alarms, and the fire alarms increased as private buildings, R-type receivers, and a large number of failure or shutoff days. In addition, factors that influencing fire alarms were different depending on the main usage of the building. In terms of time, it was found to follow people's daily patterns during weekdays(9 am to 6 pm), and each peaked around 10 am and 2 pm. This study was claimed that it is necessary to investigate the building environment that caused the fire alarms, along with the system internal inspection. Also, it propose additional recording of building environment data in real-time for follow-up research and system enhancement.

• Fire Science and Engineering
• /
• v.31 no.1
• /
• pp.58-62
• /
• 2017

There is a growing need for seismic resistance design. But it is controversial that standards of sway brace device in non-structural elements for buildings like pump waterway is vary widely. Therefore, in this study to get a valid range of sway brace device in seismic resistance design, using load test of sway brace device. As a result, load of safe range from 0 to 18.5 kN and under 29.4 kN, no structural fault of sway brace device. And using internet of things get a data of seismic resistance design from sensor node like accelerometer, GPS, tilt sensor and temperature sensor through steps of sampling and prediction. These results will be acceptable for monitoring system for seismic resistance in non-structural elements.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.6
• /
• pp.1077-1082
• /
• 2019

The development of computing technology and networking has developed into a fundamental technology of the Fourth Industrial Revolution, which provides a ubiquitous environment. In the ubiquitous environment, the IoT environment has become an issue so that various devices and the things can be actively accessed and connected. Also, the RFID system using the wireless identification code attaches an RFID tag to the object, such as the production and distribution of products. It is applied to the management very efficiently. EPCglobal is conducting a research on RFID system standardization and various security studies. Since RFID systems use wireless environment technology, there are more security threats than wire problems. In particular, failure to provide confidentiality, indistinguishability, and forward safety could expose them to various threats in the Fourth Industrial Revolution. Therefore, this study analyzes the standard method of EPCgolbal and proposes RFID security method using hash code that can consider the amount of computation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.28 no.1
• /
• pp.10-18
• /
• 2017

In this paper, we designed and implemented a visible light identification(VLID) system consisting of a VLID reader and a tag which backscatters incident lights from the reader. A VLID tag sends its ID to the reader by switching an LCD shutter which is located on its surface. The VLID reader consists of six LEDs and a photodiode(PD). The LEDs emit visible light and a PD located in a center position of LEDs receives backscattered light from the VLID tag. A microcontroller and a commercial liquid crystal display(LCD) shutter for 3D-TV glasses are used to implement a VLID tag. Experiments were conducted to confirm VLID system performance. We successfully demonstrated experiments to send NRZ-OOK signal of 100 bps over a distance of 35 cm at daytime. Also, we suggested the theoretical maximum transmission rate and the various methods to enhance the separation distance between a VLID reader and a tag.