Byung-Gyu  Kim

Dr. Byung-Gyu Kim

Department of IT Engineering, Sookmyung Women's University, Seoul 04310, Korea
orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

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

Representative Publications

View All Publications
1 June 2018 in Future Generation Computer Systems
Verified
Journal Article
Closed access
Vasileios A. MemosVasileios A. Memos
Vasileios A. Memos
Kostas PsannisKostas Psannis
Kostas Psannis
YIYutaka Ishibashi
Yutaka Ishibashi
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim
Brij GuptaBrij Gupta
Brij Gupta

25 March 2019 in IEEE Access
Verified
Journal Article
Open access
JKJi-Hae Kim
Ji-Hae Kim
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim
PRPartha Roy
Partha Roy
DJDa-Mi Jeong
Da-Mi Jeong
With the continued development of artificial intelligence (AI) technology, research on interaction technology has become more popular. Facial expression recognition (FER) is an important type of visual information that can be used to understand a human’s emotional situation. In particular, the importance of AI systems has recently increased due to advancements in research on AI systems applied to AI robots. In this paper, we propose a new scheme for FER system based on a hierarchical deep learning. The feature extracted from the appearance feature-based network is fused with the geometric feature in a hierarchical structure. The appearance feature-based network extracts holistic features of the face using the preprocessed LBP image, while the geometric feature-based network learns the coordinate change of action units (AUs) landmark, which is a muscle that moves mainly when making facial expressions. The proposed method combines the result of the softmax function of two features by considering the error associated with the second highest emotion (Top-2) prediction result. In addition, we propose a technique to generate facial images with neutral emotion using the autoencoder technique. By this technique, we can extract the dynamic facial features between the neutral and emotional images without sequence data. We compare the proposed algorithm with the other recent algorithms for CK+ and JAFFE dataset, which are typically considered to be verified data sets in the facial expression recognition. The 10-fold cross validation results show 96.46% of accuracy in the CK+ dataset and 91.27% of accuracy in the JAFFE dataset, respectively. When comparing with other methods, the result of the proposed hierarchical deep network structure shows up to about 3% of the accuracy improvement and 1.3% of average improvement in CK+ dataset, respectively. In JAFFE datasets, up to about 7% of the accuracy is enhanced, and the average improvement is verified by about 1.5%.

1 October 2020 in Electronics
Verified
Journal Article
Open access
PDF file
Ashutosh SharmaAshutosh Sharma
Ashutosh Sharma
S.Sarishma .
Sarishma .
Ravi TomarRavi Tomar
Ravi Tomar
Naveen ChilamkurtiNaveen Chilamkurti
Naveen Chilamkurti
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim
The concept of Blockchain has penetrated a wide range of scientific areas, and its use is considered to rise exponentially in the near future. Executing short scripts of predefined code called smart contracts on Blockchain can eliminate the need of intermediaries and can also raise the multitude of execution of contracts. In this paper, we discuss the concept of Blockchain along with smart contracts and discuss their applicability in the Internet of Medical Things (IoMT) in the e-healthcare domain. The paper analyses the dimensions that decentralization and the use of smart contracts will take the IoMT in e-healthcare, proposes a novel architecture, and also outlines the advantages, challenges, and future trends related to the integration of all three. The proposed architecture shows its effectiveness with average packet delivery ratio, average latency, and average energy efficiency performance parameters when compared with traditional approaches.

26 July 2022 in Applied Intelligence
Verified
Journal Article
Closed access
PDF file
YHYoung-Jin Heo
Young-Jin Heo
WYWoon-Ha Yeo
Woon-Ha Yeo
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim

2 March 2023 in ACM Transactions on Sensor Networks
Verified
Journal Article
Open access
PSPratima Sharma
Pratima Sharma
SNSuyel Namasudra
Suyel Namasudra
Naveen ChilamkurtiNaveen Chilamkurti
Naveen Chilamkurti
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim
Rubén González CrespoRubén González Crespo
Rubén González Crespo
Blockchain technology provides a secure and reliable platform for managing data in various application areas, such as supply chain management, multimedia, financial sector, food sector,Internet of Things (IoT), healthcare, and many more. The recent emergence of blockchain with IoT provides significant growth in the healthcare industry to improve security, privacy, efficiency, and transparency with more business opportunities. Nevertheless, conventional healthcare schemes suffer from various security attacks like collusion, phishing, masquerade, etc. Therefore, a privacy-preservingDistributed Application (DA)is proposed in this paper using blockchain technology to create and maintain healthcare certificates. Here, the distributed application provides an interface between the blockchain network and system objects like healthcare centers, verifiers, and regular authorities to generate and issue medical documents. In addition, it also ensures security by specifying rules using various smart contracts. To evaluate the performance of the proposed scheme, various experimental tests are conducted using the Etherscan tool for measuring operation cost, latency, and processing time. Here, the efficiency of the proposed system is also compared to the existing systems in terms of latency, throughput, and response time. The experimental results and comparative analysis show that the proposed work is more efficient than the existing techniques.

28 September 2020 in Remote Sensing
Verified
Journal Article
Open access
PDF file
Manoj ChhetriManoj Chhetri
Manoj Chhetri
SKSUDHANSHU KUMAR
SUDHANSHU KUMAR
PRPartha Roy
Partha Roy
Byung-Gyu  KimByung-Gyu Kim
Byung-Gyu Kim
Rainfall prediction is an important task due to the dependence of many people on it, especially in the agriculture sector. Prediction is difficult and even more complex due to the dynamic nature of rainfalls. In this study, we carry out monthly rainfall prediction over Simtokha a region in the capital of Bhutan, Thimphu. The rainfall data were obtained from the National Center of Hydrology and Meteorology Department (NCHM) of Bhutan. We study the predictive capability with Linear Regression, Multi-Layer Perceptron (MLP), Convolutional Neural Network (CNN), Long Short Term Memory (LSTM), Gated Recurrent Unit (GRU), and Bidirectional Long Short Term Memory (BLSTM) based on the parameters recorded by the automatic weather station in the region. Furthermore, this paper proposes a BLSTM-GRU based model which outperforms the existing machine and deep learning models. From the six different existing models under study, LSTM recorded the best Mean Square Error (MSE) score of 0.0128. The proposed BLSTM-GRU model outperformed LSTM by 41.1% with a MSE score of 0.0075. Experimental results are encouraging and suggest that the proposed model can achieve lower MSE in rainfall prediction systems.