So-Hyeon Jo

Dr. So-Hyeon Jo


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 November 2022 in Sensors
Verified
Journal Article
Open access
PDF file
JWJoo Woo
Joo Woo
JBJi-Hyeon Baek
Ji-Hyeon Baek
SJSo-Hyeon Jo
So-Hyeon Jo
Sun Young KimSun Young Kim
Sun Young Kim
JJJae-Hoon Jeong
Jae-Hoon Jeong
Recently, autonomous driving technology has been in the spotlight. However, autonomous driving is still in its infancy in the railway industry. In the case of railways, there are fewer control elements than autonomous driving of cars due to the characteristics of running on railways, but there is a disadvantage in that evasive maneuvers cannot be made in the event of a dangerous situation. In addition, when braking, it cannot be decelerated quickly for the weight of the body and the safety of the passengers. In the case of a tram, one of the railway systems, research has already been conducted on how to generate a profile that plans braking and acceleration as a base technology for autonomous driving, and to find the location coordinates of surrounding objects through object recognition. In pilot research about the tram’s automated driving, YOLOv3 was used for object detection to find object coordinates. YOLOv3 is an artificial intelligence model that finds coordinates, sizes, and classes of objects in an image. YOLOv3 is the third upgrade of YOLO, which is one of the most famous object detection technologies based on CNN. YOLO’s object detection performance is characterized by ordinary accuracy and fast speed. For this paper, we conducted a study to find out whether the object detection performance required for autonomous trams can be sufficiently implemented with the already developed object detection model. For this experiment, we used the YOLOv4 which is the fourth upgrade of YOLO.

30 September 2021 in Sensors
Verified
Journal Article
Open access
PDF file
SJSo-Hyeon Jo
So-Hyeon Jo
JWJoo Woo
Joo Woo
GBGi-Sig Byun
Gi-Sig Byun
BKBaek-soon Kwon
Baek-soon Kwon
JJJae-Hoon Jeong
Jae-Hoon Jeong
The traffic accident occurrence rate is increasing relative to the increase in the number of people using personal mobility device (PM). This paper proposes an airbag system with a more efficient algorithm to decide the deployment of a wearable bike airbag in case of an accident. The existing wearable airbags are operated by judging the accident situations using the thresholds of sensors. However, in this case, the judgment accuracy can drop against various motions. This study used the long short-term memory (LSTM) model using the sensor values of the inertial measurement unit (IMU) as input values to judge accident occurrences, which obtains data in real time from the three acceleration-axis and three angular velocity-axis sensors on the driver motion states and judges whether or not an accident has occurred using the obtained data. The existing neural network (NN) or convolutional neural network (CNN) model judges only the input data. This study confirmed that this model has a higher judgment accuracy than the existing NN or CNN by giving strong points even in “past information” through LSTM by regarding the driver motion as time-series data.

19 July 2019 in Journal of Electrical Engineering & Technology
Verified
Journal Article
Closed access
PDF file
SJSo-Hyeon Jo
So-Hyeon Jo
JWJoo Woo
Joo Woo
JJJae-Hoon Jeong
Jae-Hoon Jeong
GBGi-Sig Byun
Gi-Sig Byun

14 June 2021 in Electronics
Verified
Journal Article
Open access
PDF file
JWJoo Woo
Joo Woo
SJSo-Hyeon Jo
So-Hyeon Jo
GBGi-Sig Byun
Gi-Sig Byun
BKBaek-soon Kwon
Baek-soon Kwon
JJJae-Hoon Jeong
Jae-Hoon Jeong
As demand for bicycles increases, bicycle-related accidents are on the rise. There are many items such as helmets and racing suits for bicycles, but many people do not wear helmets even if they are the most basic safety protection. To protect the rider from accidents, technology is needed to measure the rider’s motion condition in real time, determine whether an accident has occurred, and cope with the accident. This paper describes an artificial intelligence airbag. The artificial intelligence airbag is a system that measures real-time motion conditions of a bicycle rider using a six-axis sensor and judges accidents with artificial intelligence to prevent neck injuries. The MPU 6050 is used to understand changes in the rider’s movement in normal and accident conditions. The angle is determined by using the measured data and artificial intelligence to determine whether an accident happened or not by analyzing acceleration and angle. In this paper, similar methods of artificial intelligence (NN, PNN, CNN, PNN-CNN) to are compared to the orthogonal convolutional neural network (O-CNN) method in terms of the performance of judgment accuracy for accident situations. The artificial neural networks were applied to the airbag system and verified the reliability and judgment in advance.

17 April 2021 in Energies
Verified
Journal Article
Open access
PDF file
SJSo-Hyeon Jo
So-Hyeon Jo
JWJoo Woo
Joo Woo
GBGi-Sig Byun
Gi-Sig Byun
JJJae-Hoon Jeong
Jae-Hoon Jeong
HJHeon Jeong
Heon Jeong
The risk of environmental pollution is a consequence of every kind of energy, including fossil fuels, nuclear power plants, and thermoelectric power plants. For the purpose of reducing the use ratio of such energy, research on eco-friendly energy is being actively carried out, and has shown that among all kinds of energy, solar energy has an advantage: it can supply us with inexhaustible clean energy. However, since solar energy depends on sunlight, the output may be unstable as it is influenced by weather or surrounding structures. In this paper, there is presented a control system which transmits power to a storage device, in a specific state, after the energy of the low-illumination section is charged in a supercapacitor using the accumulation-type controller by use of a supercapacitor. Feedback from the power output of photovoltaic panels (PVs) demonstrates that the power of the low-illumination section can be charged without being discarded. The charging rate was compared with other solar controllers being sold on the market, and the comparison was made through state of charge (SOC) measurements after the battery had been charged by photovoltaic panels for a whole day. It was confirmed that the solar controller, by use of supercapacitor integrator proposed in this paper, stored higher levels of energy than the existing solar controllers over the same hours and under the same conditions.

11 April 2022 in Sensors
Verified
Journal Article
Open access
PDF file
JWJoo Woo
Joo Woo
SJSo-Hyeon Jo
So-Hyeon Jo
GBGi-Sig Byun
Gi-Sig Byun
Sun Young KimSun Young Kim
Sun Young Kim
SJSeok-Geun Jee
Seok-Geun Jee
JJJae-Hoon Jeong
Jae-Hoon Jeong
Currently, the location recognition and positioning system are the essential parts of unmanned vehicles. Among them, location estimation under GPS-denied environments is currently being studied using IMU, Wi-Fi, and VLC, but there are problems such as cumulative errors, hardware complexity, and precision positioning. To address this problem with the current positioning system, the present study proposed a lane positioning technique by analyzing the chromaticity coordinates, judging from the color temperature of LED lights in tunnels. The tunnel environment was built using LEDs with three color temperatures, and to solve nonlinear problems such as lane positioning from chromaticity analysis, a single input single output fuzzy algorithm was developed to estimate the position of an object on lanes using chromaticity values of signals measured by RGB sensors. The RGB value measured by the sensor removes the disturbance through the pre-processing filter, accepts only the tunnel LED information, and estimates where it is located on the x-distance indicating the lane position through a fuzzy algorithm. Finally, the performance of the fuzzy algorithm was evaluated through experiments, and the accuracy was shown with an average error of less than 4.86%.