Ju Hong Park

Dr. Ju Hong Park

Pohang University of Science and Technology
orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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22 February 2022 in Sensors
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Journal Article
Open access
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AAAli Abdi
Ali Abdi
MRMohammad Hassan Ranjbar
Mohammad Hassan Ranjbar
JPJu Hong Park
Ju Hong Park
Computer vision-based path planning can play a crucial role in numerous technologically driven smart applications. Although various path planning methods have been proposed, limitations, such as unreliable three-dimensional (3D) localization of objects in a workspace, time-consuming computational processes, and limited two-dimensional workspaces, remain. Studies to address these problems have achieved some success, but many of these problems persist. Therefore, in this study, which is an extension of our previous paper, a novel path planning approach that combined computer vision, Q-learning, and neural networks was developed to overcome these limitations. The proposed computer vision-neural network algorithm was fed by two images from two views to obtain accurate spatial coordinates of objects in real time. Next, Q-learning was used to determine a sequence of simple actions: up, down, left, right, backward, and forward, from the start point to the target point in a 3D workspace. Finally, a trained neural network was used to determine a sequence of joint angles according to the identified actions. Simulation and experimental test results revealed that the proposed combination of 3D object detection, an agent-environment interaction in the Q-learning phase, and simple joint angle computation by trained neural networks considerably alleviated the limitations of previous studies.

23 July 2021 in Applied Sciences
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Journal Article
Open access
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AAAli Abdi
Ali Abdi
Dibash AdhikariDibash Adhikari
Dibash Adhikari
JPJu Hong Park
Ju Hong Park
Path planning for robot arms to reach a target and avoid obstacles has had a crucial role in manufacturing automation. Although many path planning algorithms, including RRT, APF, PRM, and RL-based, have been presented, they have many problems: a time-consuming process, high computational costs, slowness, non-optimal paths, irregular paths, failure to find a path, and complexity. Scholars have tried to address some of these issues. However, those methods still suffer from slowness and complexity. In order to address these two limitations, this paper presents a new hybrid path planning method that contains two separate parts: action-finding (active approach) and angle-finding (passive approach). In the active phase, the Q-learning algorithm is used to find a sequence of simple actions, including up, down, left, and right, to reach the target cell in a gridded workspace. In the passive phase, the joints angles of the robot arm, with respect to the found actions, are obtained by the trained neural network. The simulation and test results show that this hybrid approach significantly improves the slowness and complexity due to using the simplified agent-environment interaction in the active phase and simple computing the joints angles in the passive phase.

6 March 2025 in BMC Psychology
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Journal Article
Open access
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HPHyejoon Park
Hyejoon Park
MMMelinda McCormick
Melinda McCormick
JPJu Hong Park
Ju Hong Park
This study investigated the cognitive development of elementary school children by identifying significant factors within a social-ecological framework. By studying the association between social-ecological factors and children’s cognitive development, we identified the most significant factors that are linked to children’s cognitive outcomes. We used the 5th wave (9 years old) of the U.S. Fragile Family and Child Wellbeing Study. With a sample size of 1,722, we conducted multiple regression analyses to examine the relationship between individual, family, and school/community levels and children’s verbal skills (PPVT-III), reading comprehension (WJ-PC), digit span, and math problems (WJ-AP). We found that the school neighborhood was associated with verbal skills, math skills, and reading comprehension; mothers’ educational levels were significantly associated with verbal skills, digit span, and reading comprehension; and children’s race/ethnicity was associated with verbal skills. To enhance students’ cognitive development, policymakers and educators should prioritize the quality of schools and their learning environment. Creating a supportive and optimistic learning environment is crucial for all students, especially those dealing with obstacles such as poverty, family instability, and troubled schools. Providing parenting education may be helpful for parents with limited education levels.

17 October 2023 in Nano Energy
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Journal Article
Open access
HYHyeongseok Yoo
Hyeongseok Yoo
HKHyangwoo Kim
Hyangwoo Kim
HKHyeon-Tak Kwak
Hyeon-Tak Kwak
MCMinkeun Choi
Minkeun Choi
KOKyounghwan Oh
Kyounghwan Oh
CBChang-Ki Baek
Chang-Ki Baek

1 December 2023 in IEEE Access
Verified
Journal Article
Open access
AAAli Abdi
Ali Abdi
JPJu Hong Park
Ju Hong Park
Intelligent robot arms are advanced robotic systems used in Industry 4.0 to perform complex tasks. Unlike conventional robot arms, which perform predefined tasks, intelligent robot arms have autonomy and can operate in changing environments, interact with other machines, and collaborate with humans. In this regard, adaptive path planning is crucial for intelligent robot arms, involving real-time environment monitoring and path generation to continuously update the robot’s trajectory based on changes in the surroundings. This paper presents an adaptive path planning method for intelligent robot arms to be used in dynamic environments. The proposed method is based on a hybrid active-passive approach and has been tested in a dynamic workspace simulation environment. The results indicate the ability of the proposed method to respond dynamically in a complex scenario where the target is fluctuating, and an obstacle is intentionally placed in the robot’s path. Additionally, real-time analysis results show that the method can be categorized as real-time path planning with less than 100 ms reaction time for grid sizes with less than 96×96×96 cells. This insight presents opportunities for the establishment of smart factories, smart homes, and smart cities, where the presence of intelligent robot arms in dynamic environments becomes essential.

1 November 2024 in Engineering Applications of Artificial Intelligence
Verified
Journal Article
Closed access
MRMohammad Hassan Ranjbar
Mohammad Hassan Ranjbar
AAAli Abdi
Ali Abdi
JPJu Hong Park
Ju Hong Park