Beomjoon Kim

Prof. Dr. Beomjoon Kim


Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

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

Representative Publications

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6 August 2021 in Applied Sciences
Verified
Journal Article
Open access
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ZYZELALEM JEMBRE YALEW
ZELALEM JEMBRE YALEW
YNYuniarto Wimbo Nugroho
Yuniarto Wimbo Nugroho
Muhammad Toaha Raza KhanMuhammad Toaha Raza Khan
Muhammad Toaha Raza Khan
MAMuhammad Attique
Muhammad Attique
RPRajib Paul
Rajib Paul
BKBeomjoon Kim
Beomjoon Kim
Unmanned Aerial Vehicles (UAVs) are abundantly becoming a part of society, which is a trend that is expected to grow even further. The quadrotor is one of the drone technologies that is applicable in many sectors and in both military and civilian activities, with some applications requiring autonomous flight. However, stability, path planning, and control remain significant challenges in autonomous quadrotor flights. Traditional control algorithms, such as proportional-integral-derivative (PID), have deficiencies, especially in tuning. Recently, machine learning has received great attention in flying UAVs to desired positions autonomously. In this work, we configure the quadrotor to fly autonomously by using agents (the machine learning schemes being used to fly the quadrotor autonomously) to learn about the virtual physical environment. The quadrotor will fly from an initial to a desired position. When the agent brings the quadrotor closer to the desired position, it is rewarded; otherwise, it is punished. Two reinforcement learning models, Q-learning and SARSA, and a deep learning deep Q-network network are used as agents. The simulation is conducted by integrating the robot operating system (ROS) and Gazebo, which allowed for the implementation of the learning algorithms and the physical environment, respectively. The result has shown that the Deep Q-network network with Adadelta optimizer is the best setting to fly the quadrotor from the initial to desired position.

8 February 2022 in Electronics
Verified
Journal Article
Open access
PDF file
ZYZELALEM JEMBRE YALEW
ZELALEM JEMBRE YALEW
WJWoon-Young Jung
Woon-Young Jung
MAMuhammad Attique
Muhammad Attique
RPRajib Paul
Rajib Paul
BKBeomjoon Kim
Beomjoon Kim
Five decades have passed since the first bit was transmitted over the internet. Although the internet has improved our lives and led to the digital economy, currently only 51% of the world’s population have access to it. Currently, consumers mostly access the internet via mobile broadband, 2G, 3G, and 4G services. Regulatory bodies such as the Federal Communications Commission (FCC) of the US are responsible for ensuring that consumers receive an adequate service from Mobile Network Operators (MNOs). Usually, regulators evaluate the performance of each MNO in terms of service quality yearly and publish a report. To evaluate performance, metrics such as coverage, download/upload speed, and the number of subscribers can be used. However, the evaluation process and the metrics used by each regulatory body are inconsistent, and this makes it hard to determine which nations are providing adequate services to their citizens. Furthermore, it is not clear as to which performance evaluation is the right path. In this case study, we analyzed the reports released from eight nations (United States of America, United Kingdom, France, South Korea, Japan, Singapore, and Australia) as of the year 2020. We then point out the advantages and the drawbacks of the current evaluation process and metrics. Furthermore, a discussion on why the current methods are not sufficient to evaluate 5G services is presented. Our findings indicate that there is a great need for a unified metric and that this process becomes more complex with the rollout of 5G.

1 January 2006 in IEICE Transactions on Communications
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Journal Article
Closed access
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BKBeomjoon Kim
Beomjoon Kim
YCYong-Hoon Choi
Yong-Hoon Choi
JLJaiyong Lee
Jaiyong Lee


18 April 2005 in IEEE Communications Magazine
Verified
Journal Article
Closed access
YCYong-Hoon Choi
Yong-Hoon Choi
JPJaesung Park
Jaesung Park
BKBeomjoon Kim
Beomjoon Kim
MSM.A. Shayman
M.A. Shayman
With the fast proliferation of QoS-enabled wireless packet networks, the need for effective QoS control is increasing. In this article, we focus on QoS provisioning in the cdma2000 1/spl times/ evolution for high-speed integrated data and voice (1/spl times/EV-DV) packet core network. We investigate a dynamic bandwidth provisioning method that is able to increase a service provider's revenue. It is achieved by releasing unutilized bandwidth for use by other profitable services. The proposed method is implemented as an SNMP-compliant management information base and deployed at the packet data serving node. The experiments conducted on the LG Telecom 1/spl times/EV-DV testbed show that the method can increase the bandwidth for the conversational class and guarantee adequate service quality for the background class as well.

30 April 2012 in The KIPS Transactions:PartC
Verified
Journal Article
Closed access
CKChin-Chol Kim
Chin-Chol Kim
BKBeomjoon Kim
Beomjoon Kim