Kil-houm Park

Prof. Dr. Kil-houm Park


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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19 December 2018 in Sensors
Verified
Journal Article
Open access
PDF file
SLSeungmin Lee
Seungmin Lee
YJYoosoo Jeong
Yoosoo Jeong
Daejin ParkDaejin Park
Daejin Park
BYByoung-Ju Yun
Byoung-Ju Yun
KPKil-houm Park
Kil-houm Park
Electrocardiogram signal analysis is based on detecting a fiducial point consisting of the onset, offset, and peak of each waveform. The accurate diagnosis of arrhythmias depends on the accuracy of fiducial point detection. Detecting the onset and offset fiducial points is ambiguous because the feature values are similar to those of the surrounding sample. To improve the accuracy of this paper’s fiducial point detection, the signal is represented by a small number of vertices through a curvature-based vertex selection technique using polygonal approximation. The proposed method minimizes the number of candidate samples for fiducial point detection and emphasizes these sample’s feature values to enable reliable detection. It is also sensitive to the morphological changes of various QRS complexes by generating an accumulated signal of the amplitude change rate between vertices as an auxiliary signal. To verify the superiority of the proposed algorithm, error distribution is measured through comparison with the QT-DB annotation provided by Physionet. The mean and standard deviation of the onset and the offset were stable as − 4.02 ± 7.99 ms and − 5.45 ± 8.04 ms, respectively. The results show that proposed method using small number of vertices is acceptable in practical applications. We also confirmed that the proposed method is effective through the clustering of the QRS complex. Experiments on the arrhythmia data of MIT-BIH ADB confirmed reliable fiducial point detection results for various types of QRS complexes.

7 July 2021 in Applied Sciences
Verified
Journal Article
Open access
PDF file
TKTae-Gu Kim
Tae-Gu Kim
BYByoung-Ju Yun
Byoung-Ju Yun
TKTae-Hun Kim
Tae-Hun Kim
JLJae-Young Lee
Jae-Young Lee
KPKil-houm Park
Kil-houm Park
HKHyun Deok Kim
Hyun Deok Kim
In this study, we have proposed an algorithm that solves the problems which occur during the recognition of a vehicle license plate through closed-circuit television (CCTV) by using a deep learning model trained with a general database. The deep learning model which is commonly used suffers with a disadvantage of low recognition rate in the tilted and low-resolution images, as it is trained with images acquired from the front of the license plate. Furthermore, the vehicle images acquired by using CCTV have issues such as limitation of resolution and perspective distortion. Such factors make it difficult to apply the commonly used deep learning model. To improve the recognition rate, an algorithm which is a combination of the super-resolution generative adversarial network (SRGAN) model, and the perspective distortion correction algorithm is proposed in this paper. The accuracy of the proposed algorithm was verified with a character recognition algorithm YOLO v2, and the recognition rate of the vehicle license plate image was improved 8.8% from the original images.

6 September 2018 in Symmetry
Verified
Journal Article
Open access
PDF file
YJYoosoo Jeong
Yoosoo Jeong
SLSeungmin Lee
Seungmin Lee
Daejin ParkDaejin Park
Daejin Park
KPKil-houm Park
Kil-houm Park
Recently, there have been many studies on the automatic extraction of facial information using machine learning. Age estimation from frontal face images is becoming important, with various applications. Our proposed work is based on a binary classifier that only determines whether two input images are clustered in a similar class and trains a convolutional neural network (CNN) model using the deep metric learning method based on the Siamese network. To converge the results of the training Siamese network, two classes, for which age differences are below a certain level of distance, are considered as the same class, so the ratio of positive database images is increased. The deep metric learning method trains the CNN model to measure similarity based only on age data, but we found that the accumulated gender data can also be used to compare ages. Thus, we adopted a multi-task learning approach to consider the gender data for more accurate age estimation. In the experiment, we evaluated our approach using MORPH and MegaAge-Asian datasets, and compared gender classification accuracy only using age data from the training images. In addition, using gender classification, our proposed architecture, which is trained with only age data, performs age comparison using the self-generated gender feature. The accuracy enhancement by multi-task learning, i.e. simultaneously considering age and gender data, is discussed. Our approach results in the best accuracy among the methods based on deep metric learning on MORPH dataset. Additionally, our method has better results than the state of the art in terms of age estimation on MegaAge-Asian and MORPH datasets.

14 March 2024 in Electronics
Verified
Journal Article
Open access
PDF file
SSSang Mun Shin
Sang Mun Shin
ARAsad Rasheed
Asad Rasheed
KPKil-houm Park
Kil-houm Park
Kalyana Chakravarthy VeluvoluKalyana Chakravarthy Veluvolu
Kalyana Chakravarthy Veluvolu
Short-term electric load forecasting (STLF) plays a pivotal role in modern power system management, bolstering forecasting accuracy and efficiency. This enhancement assists power utilities in formulating robust operational strategies, consequently fostering economic and social advantages within the systems. Existing methods employed for STLF either exhibit poor forecasting performance or require longer computational time. To address these challenges, this paper introduces a hybrid learning approach comprising variational mode decomposition (VMD) and random vector functional link network (RVFL). The RVFL network, serving as a universal approximator, showcases remarkable accuracy and fast computation, owing to the randomly generated weights connecting input and hidden layers. Additionally, the direct links between hidden and output layers, combined with the availability of a closed-form solution for parameter computation, further contribute to its efficiency. The effectiveness of the proposed VMD-RVFL was assessed using electric load datasets obtained from the Australian Energy Market Operator (AEMO). Moreover, the effectiveness of the proposed method is demonstrated by comparing it with existing benchmark forecasting methods using two performance indices such as root mean square error (RMSE) and mean absolute percentage error (MAPE). As a result, our proposed method requires less computational time and yielded accurate and robust prediction performance when compared with existing methods.

1 March 2011 in Optical Review
Verified
Journal Article
Closed access
PDF file
SKSe-Yun Kim
Se-Yun Kim
YSYoung-Chul Song
Young-Chul Song
CJChang-Do Jung
Chang-Do Jung
KPKil-houm Park
Kil-houm Park

30 June 2015 in Optical Review
Verified
Journal Article
Closed access
PDF file
ELEunyoung Lee
Eunyoung Lee
EGEunhye Gu
Eunhye Gu
KPKil-houm Park
Kil-houm Park