Ki-Baek Lee

Prof. Ki-Baek Lee

Kwangwoon University
orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

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

Representative Publications

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24 April 2023 in Nature Communications
Verified
Journal Article
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SLSeungmin Lee
Seungmin Lee
SKSunmok Kim
Sunmok Kim
DYDae Sung Yoon
Dae Sung Yoon
JPJeong Soo Park
Jeong Soo Park
HWHyowon Woo
Hyowon Woo
JLJeong Hoon Lee
Jeong Hoon Lee
Since many lateral flow assays (LFA) are tested daily, the improvement in accuracy can greatly impact individual patient care and public health. However, current self-testing for COVID-19 detection suffers from low accuracy, mainly due to the LFA sensitivity and reading ambiguities. Here, we present deep learning-assisted smartphone-based LFA (SMARTAI-LFA) diagnostics to provide accurate decisions with higher sensitivity. Combining clinical data learning and two-step algorithms enables a cradle-free on-site assay with higher accuracy than the untrained individuals and human experts via blind tests of clinical data (n = 1500). We acquired 98% accuracy across 135 smartphone application-based clinical tests with different users/smartphones. Furthermore, with more low-titer tests, we observed that the accuracy of SMARTAI-LFA was maintained at over 99% while there was a significant decrease in human accuracy, indicating the reliable performance of SMARTAI-LFA. We envision a smartphone-based SMARTAI-LFA that allows continuously enhanced performance by adding clinical tests and satisfies the new criterion for digitalized real-time diagnostics.

9 August 2020 in Sensors
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Journal Article
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YHYoung-Dae Hong
Young-Dae Hong
YKYoung-Joo Kim
Young-Joo Kim
Ki-Baek LeeKi-Baek Lee
Ki-Baek Lee
This paper proposes a novel online object-packing system which can measure the dimensions of every incoming object and calculate its desired position in a given container. Existing object-packing systems have the limitations of requiring the exact information of objects in advance or assuming them as boxes. Thus, this paper is mainly focused on the following two points: (1) Real-time calculation of the dimensions and orientation of an object; (2) Online optimization of the object’s position in a container. The dimensions and orientation of the object are obtained using an RGB-D sensor when the object is picked by a manipulator and moved over a certain position. The optimal position of the object is calculated by recognizing the container’s available space using another RGB-D sensor and minimizing the cost function that is formulated by the available space information and the optimization criteria inspired by the way people place things. The experimental results show that the proposed system successfully places the incoming various shaped objects in their proper positions.

18 July 2018 in Applied Sciences
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Ki-Baek LeeKi-Baek Lee
Ki-Baek Lee
YKYoung-Joo Kim
Young-Joo Kim
YHYoung-Dae Hong
Young-Dae Hong
This paper proposes a novel search method for a swarm of quadcopter drones. In the proposed method, inspired by the phenomena of swarms in nature, drones effectively look for the search target by investigating the evidence from the surroundings and communicating with each other. The position update mechanism is implemented using the particle swarm optimization algorithm as the swarm intelligence (a well-known swarm-based optimization algorithm), as well as a dynamic model for the drones to take the real-world environment into account. In addition, the mechanism is processed in real-time along with the movements of the drones. The effectiveness of the proposed method was verified through repeated test simulations, including a benchmark function optimization and air pollutant search problems. The results show that the proposed method is highly practical, accurate, and robust.

5 August 2022 in Remote Sensing
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Journal Article
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JMJIWON MOON
JIWON MOON
SLSangkyu Kyu Lim
Sangkyu Kyu Lim
HLHakjun Lee
Hakjun Lee
YSYu Seungbum
Yu Seungbum
Ki-Baek LeeKi-Baek Lee
Ki-Baek Lee
Object counting is an indispensable task in manufacturing and management. Recently, the development of image-processing techniques and deep learning object detection has achieved excellent performance in object-counting tasks. Accordingly, we propose a novel small-size smart counting system composed of a low-cost hardware device and a cloud-based object-counting software server to implement an accurate counting function and overcome the trade-off presented by the computing power of local hardware. The cloud-based object-counting software consists of a model adapted to the object-counting task through a novel DBC-NMS (our own technique) and hyperparameter tuning of deep-learning-based object-detection methods. With the power of DBC-NMS and hyperparameter tuning, the performance of the cloud-based object-counting software is competitive over commonly used public datasets (CARPK and SKU110K) and our custom dataset of small pills. Our cloud-based object-counting software achieves an mean absolute error (MAE) of 1.03 and a root mean squared error (RMSE) of 1.20 on the Pill dataset. These results demonstrate that the proposed smart counting system accurately detects and counts densely distributed object scenes. In addition, the proposed system shows a reasonable and efficient cost–performance ratio by converging low-cost hardware and cloud-based software.

7 August 2018 in ETRI Journal
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Journal Article
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YJYangho Ji
Yangho Ji
SKSunmok Kim
Sunmok Kim
YKYoung-Joo Kim
Young-Joo Kim
Ki-Baek LeeKi-Baek Lee
Ki-Baek Lee
This paper proposes a human‐like sign‐language learning method that uses a deep‐learning technique. Inspired by the fact that humans can learn sign language from just a set of pictures in a book, in the proposed method, the input data are pre‐processed into an image. In addition, the network is partially pre‐trained to imitate the preliminarily obtained knowledge of humans. The learning process is implemented with a well‐known network, that is, a convolutional neural network. Twelve sign actions are learned in 10 situations, and can be recognized with an accuracy of 99% in scenarios with low‐cost equipment and limited data. The results show that the system is highly practical, as well as accurate and robust.

31 October 2021 in Applied Sciences
Verified
Journal Article
Open access
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HKHyungsuk Kim
Hyungsuk Kim
JPJuyoung Park
Juyoung Park
HLHakjun Lee
Hakjun Lee
GIGeuntae Im
Geuntae Im
JLJongsoo Lee
Jongsoo Lee
Heungjae LeeHeungjae Lee
Heungjae Lee
Ultrasound (US) imaging is widely utilized as a diagnostic screening method, and deep learning has recently drawn attention for the analysis of US images for the pathological status of tissues. While low image quality and poor reproducibility are the common obstacles in US analysis, the small size of the dataset is a new limitation for deep learning due to lack of generalization. In this work, a convolutional neural network (CNN) using multiple feature maps, such as entropy and phase images, as well as a B-mode image, was proposed to classify breast US images. Although B-mode images contain both anatomical and textual information, traditional CNNs experience difficulties in abstracting features automatically, especially with small datasets. For the proposed CNN framework, two distinct feature maps were obtained from a B-mode image and utilized as new inputs for training the CNN. These feature maps can also be made from the evaluation data and applied to the CNN separately for the final classification decision. The experimental results with 780 breast US images in three categories of benign, malignant, and normal, showed that the proposed CNN framework using multiple feature maps exhibited better performances than the traditional CNN with B-mode only for most deep network models.