• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.05a
• /
• pp.305-307
• /
• 2021

In this paper, we propose a study related to the development of a Digital-Twin platform using a smart factory based CPPS (Cyber Pysical Production System) using ICT (Information Communication Technology) technology. The platform developed through this study performs a 3D model simulation function in conjunction with P3R (Product, Process, Plant, Resource) including BOP (Bill of Process) management function from the preceding manufacturing process planning stage. In addition, we propose a digital twin platform that can predict production processes, equipment, layout, and production. The platform proposed through this paper proposes a feature that can manage the entire smart factory manufacturing process from the initial planning design stage to the manufacturing, production, operation, and maintenance stages.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.05a
• /
• pp.626-629
• /
• 2021

Recent home appliances requires convenience and low-power consumption. A convenient devices should be simple to control while having several functions. Intelligent sensors and utilization technologies are required to reduce energy consumption. This paper provides a smart drying system with Bluetooth communication function and energy reduction function. Design a control system that uses the Bluetooth function so that the smartphone monitors the drying control and the internal humidity condition. By detecting the humidity inside the dryer and controlling the speed of the motor, it has an energy-saving function.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.05a
• /
• pp.541-543
• /
• 2021

Recently, the number of cars owned in Jeju Island and the use of tourist rental cars have been increasing rapidly. Therefore, parking problems are getting worse in residential and commercial areas. As a result, a system is required to secure parking spaces and utilize existing parking spaces. Therefore, this paper proposes a system for real-time sharing of free public and paid parking spaces by introducing services that provide information on nearby restaurants, tourist information, and real-time parking status. The system analyzes infrared sensors and CCTV images installed in the actual parking lot and provides convenience for service users by analyzing the space currently in use and the number of unused parking spaces in real time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.10a
• /
• pp.649-651
• /
• 2021

In Korea, there are around 30,000 cardiac arrest patients annually. Gradually the number is increasing. Against this background, CPR education and publicity programs were expanded nationwide, but the rate of witness CPR by the general public was 4.4%, which is significantly lower than the 20%~70% rate in other countries. Therefore, in this paper, we analyzed the factors affecting the performance of CPR by witnesses who discovered cardiac arrest patients. Based on the results, an application planning and development study was conducted to provide users with correct cardiorespiratory response tips and step-by-step CPR guidelines to help users effectively assist in increasing the rate of CPR by general eyewitnesses.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.10a
• /
• pp.391-393
• /
• 2021

In this paper, we introduce a long short-term memory (LSTM)-based fall detection system using TensorFlow that can detect falls occurring in the elderly in daily living. 3-axis accelerometer data are aggregated for fall detection, and then three types of parameter are calculated. 4 types of activity of daily living (ADL) and 3 types of fall situation patterns are classified. The parameterized data applied to LSTM. Learning proceeds until the Loss value becomes 0.5 or less. The results are calculated for each parameter θ, SVM, and GSVM. The best result was GSVM, which showed Sensitivity 98.75%, Specificity 99.68%, and Accuracy 99.28%.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.10a
• /
• pp.226-228
• /
• 2021

We propose a fall recognition system using the Pose Detection of Google ML kit using video data. Using the Pose detection algorithm, 33 three-dimensional feature points extracted from the body are used to recognize the fall. The algorithm that recognizes the fall by analyzing the extracted feature points uses k-NN. While passing through the normalization process in order not to be influenced in the size of the human body within the size of image and image, analyzing the relative movement of the feature points and the fall recognizes, thirteen of the thriteen test videos recognized the fall, showing an 100% success rate.

• Transactions of the Korean hydrogen and new energy society
• /
• v.33 no.2
• /
• pp.158-163
• /
• 2022

The test method on the Type II high-pressure hydrogen storage tanks made of the metal wire hoop winding is a complex and high risk. Also closeup on the tank being test is difficult. In this study, we studied a mechanical test method for a high-pressure hydrogen tanks. This method must be simple, risk-free and possible to observe the change in microscopic behavior of a metal wire on a liner. As the results, it was possible to observe the microscopic behavior on the metal wire by the mechanical test method. Also, a simple and risk-free test was possible compared to the conventional test method for high pressure hydrogen tanks.

• Journal of the Korean Society of Industry Convergence
• /
• v.26 no.5
• /
• pp.725-731
• /
• 2023

In this study, the harmless crack size was evaluated using carburized, quenched-tempered SCM822H steel. The possibility of detecting cracks that reduce the fatigue limit by non-destructive inspection was evaluated. The conclusions obtained are as follows. The retained austenite of surface was reduced by SP. About 35% and 65% of the retained austenite on the surface were transformed into strain-induced martensite, increasing the hardness by 79HV and 122HV over the as-received material. The maximum compressive residual stresses introduced on the surfaces were -695 MPa and -688 MPa, respectively. The fatigue limit increased by 1.48 times and 1.67 times, respectively, compared to the as-received material. The harmless crack size of SP specimen was determined differently depending on the shot ball size.

• Journal of the Korean Society of Industry Convergence
• /
• v.26 no.5
• /
• pp.813-823
• /
• 2023

In this study, microstructure, hardening layer hardness, and case depth were evaluated after induction hardening(IH) of base metal specimen(BM) treated with annealing and quenching-tempering specimen(QT) treated with quenching and tempering. The microstructure after IH was significantly influenced by the microstructure before IH and the induction coil heating movement speed, but the effect of the induction frequency was very small. The hardness of the hardened layer at an induction coil heating movement speed of 15 mm/s or less was more influenced by the microstructure before IH than the induction coil travel speed and induction frequency. The induction coil travel speed has the significantly effect on the case depth, the induction frequency has effect and the microstructure before IH has a small effect.

• Journal of the Korean Society of Industry Convergence
• /
• v.27 no.1
• /
• pp.9-15
• /
• 2024

In this study, the mechanical properties of friction stir welded A6061-T6 were evaluated. This material is used as a battery pack case material for electric vehicles. The Vickers hardness, tensile strength, and yield stress of the friction stir welding (FSW) specimen were all smaller than those of the base metal specimen. As the heat input increased, the nugget zone widened, and there were differences in hardness according to the base metal zone, heat affected zone, thermal-mechanical affected zone, and nugget zone. Mechanical properties were not proportional to heat input, and the thermal-mechanical affected zone on the advancing side was the smallest in all conditions. This is because the material flow speed increased on the advancing side, where the welding direction and the tool rotation direction were the same, forming a distinct boundary with mechanical deformation.