Gil-Jin Jang

Prof. Gil-Jin Jang

School of Electronic and Electrical Engineering, Kyungpook National University, Daegu, Republic of Korea
orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

View All Publications
4 November 2019 in Applied Biological Chemistry
Verified
Journal Article
Open access
PDF file
JLJoon-Goo Lee
Joon-Goo Lee
JHJeong-Yun Hwang
Jeong-Yun Hwang
HLHye-Eun Lee
Hye-Eun Lee
TKTae-Hun Kim
Tae-Hun Kim
JCJang-Duck Choi
Jang-Duck Choi
Gil-Jin JangGil-Jin Jang
Gil-Jin Jang
Heavy metals including Lead (Pb), Cadmium (Cd), Arsenic (As) and Aluminium (Al) were analysed in oilseeds, noodles, tea leaves and their processed or cooked products to study the effects of food processing methods on migration of heavy metals. The heavy metals were determined with ICP-MS and ICP-OES following microwave-assisted acid digestion. Heavy metals in oilseeds, noodles and teas were reduced by extracting oils, boiling noodles, and infusing teas. And the transfer of heavy metals into boiling water and infusion tea was increased as the boiling and infusion time is increased. Heavy metals in foods are water soluble and heavy metals in foods would be decreased when foods are processed or cooked with water. Furthermore, it is needed to determine the migration rates in other cooked foods and assess the risk of heavy metals with concentrations calculated by the migration rates.

11 March 2020 in JMIR mHealth and uHealth
Verified
Journal Article
Open access
JBJung Kweon Bae
Jung Kweon Bae
HRHyun-Jin Roh
Hyun-Jin Roh
JYJoon S You
Joon S You
KKKyungbin Kim
Kyungbin Kim
YAYujin Ahn
Yujin Ahn
WJWoonggyu Jung
Woonggyu Jung
Background: Approximately 90% of global cervical cancer (CC) is mostly found in low- and middle-income countries. In most cases, CC can be detected early through routine screening programs, including a cytology-based test. However, it is logistically difficult to offer this program in low-resource settings due to limited resources and infrastructure, and few trained experts. A visual inspection following the application of acetic acid (VIA) has been widely promoted and is routinely recommended as a viable form of CC screening in resource-constrained countries. Digital images of the cervix have been acquired during VIA procedure with better quality assurance and visualization, leading to higher diagnostic accuracy and reduction of the variability of detection rate. However, a colposcope is bulky, expensive, electricity-dependent, and needs routine maintenance, and to confirm the grade of abnormality through its images, a specialist must be present. Recently, smartphone-based imaging systems have made a significant impact on the practice of medicine by offering a cost-effective, rapid, and noninvasive method of evaluation. Furthermore, computer-aided analyses, including image processing–based methods and machine learning techniques, have also shown great potential for a high impact on medicinal evaluations.Objective: In this study, we demonstrate a new quantitative CC screening technique and implement a machine learning algorithm for smartphone-based endoscopic VIA. We also evaluated the diagnostic performance and practicability of the approach based on the results compared to the gold standard and from physicians’ interpretation.Methods: A smartphone-based endoscope system was developed and applied to the VIA screening. A total of 20 patients were recruited for this study to evaluate the system. Overall, five were healthy, and 15 were patients who had shown a low to high grade of cervical intraepithelial neoplasia (CIN) from both colposcopy and cytology tests. Endoscopic VIA images were obtained before a loop electrosurgical excision procedure for patients with abnormal tissues, and their histology tissues were collected. Endoscopic VIA images were assessed by four expert physicians relative to the gold standard of histopathology. Also, VIA features were extracted from multiple steps of image processing techniques to find the differences between abnormal (CIN2+) and normal (≤CIN1). By using the extracted features, the performance of different machine learning classifiers, such as k-nearest neighbors (KNN), support vector machine, and decision tree (DT), were compared to find the best algorithm for VIA. After determining the best performing classifying model, it was used to evaluate the screening performance of VIA.Results: An average accuracy of 78%, with a Cohen kappa of 0.571, was observed for the evaluation of the system by four physicians. Through image processing, 240 sliced images were obtained from the cervicogram at each clock position, and five features of VIA were extracted. Among the three models, KNN showed the best performance for finding VIA within holdout 10-fold cross-validation, with an accuracy of 78.3%, area under the curve of 0.807, a specificity of 80.3%, and a sensitivity of 75.0%, respectively. The trained model performed using an unprovided data set resulted in an accuracy of 80.8%, specificity of 84.1%, and sensitivity of 71.9%. Predictions were visualized with intuitive color labels, indicating the normal/abnormal tissue using a circular clock-type segmentation. Calculating the overlapped abnormal tissues between the gold standard and predicted value, the KNN model overperformed the average assessments of physicians for finding VIA.Conclusions: We explored the potential of the smartphone-based endoscopic VIA as an evaluation technique and used the cervicogram to evaluate normal/abnormal tissue using machine learning techniques. The results of this study demonstrate its potential as a screening tool in low-resource settings.

4 January 2021 in Applied Sciences
Verified
Journal Article
Open access
PDF file
DODonghoon Oh
Donghoon Oh
JPJeong-Sik Park
Jeong-Sik Park
JKJin-Hoi Kim
Jin-Hoi Kim
Gil-Jin JangGil-Jin Jang
Gil-Jin Jang
Speech recognition consists of converting input sound into a sequence of phonemes, then finding text for the input using language models. Therefore, phoneme classification performance is a critical factor for the successful implementation of a speech recognition system. However, correctly distinguishing phonemes with similar characteristics is still a challenging problem even for state-of-the-art classification methods, and the classification errors are hard to be recovered in the subsequent language processing steps. This paper proposes a hierarchical phoneme clustering method to exploit more suitable recognition models to different phonemes. The phonemes of the TIMIT database are carefully analyzed using a confusion matrix from a baseline speech recognition model. Using automatic phoneme clustering results, a set of phoneme classification models optimized for the generated phoneme groups is constructed and integrated into a hierarchical phoneme classification method. According to the results of a number of phoneme classification experiments, the proposed hierarchical phoneme group models improved performance over the baseline by 3%, 2.1%, 6.0%, and 2.2% for fricative, affricate, stop, and nasal sounds, respectively. The average accuracy was 69.5% and 71.7% for the baseline and proposed hierarchical models, showing a 2.2% overall improvement.

13 July 2022 in Cancers
Verified
Journal Article
Open access
PDF file
JPJinhee Park
Jinhee Park
HYHyunmo Yang
Hyunmo Yang
HRHyun-Jin Roh
Hyun-Jin Roh
WJWoonggyu Jung
Woonggyu Jung
Gil-Jin JangGil-Jin Jang
Gil-Jin Jang
Cervical cancer can be prevented and treated better if it is diagnosed early. Colposcopy, a way of clinically looking at the cervix region, is an efficient method for cervical cancer screening and its early detection. The cervix region segmentation significantly affects the performance of computer-aided diagnostics using a colposcopy, particularly cervical intraepithelial neoplasia (CIN) classification. However, there are few studies of cervix segmentation in colposcopy, and no studies of fully unsupervised cervix region detection without image pre- and post-processing. In this study, we propose a deep learning-based unsupervised method to identify cervix regions without pre- and post-processing. A new loss function and a novel scheduling scheme for the baseline W-Net are proposed for fully unsupervised cervix region segmentation in colposcopy. The experimental results showed that the proposed method achieved the best performance in the cervix segmentation with a Dice coefficient of 0.71 with less computational cost. The proposed method produced cervix segmentation masks with more reduction in outliers and can be applied before CIN detection or other diagnoses to improve diagnostic performance. Our results demonstrate that the proposed method not only assists medical specialists in diagnosis in practical situations but also shows the potential of an unsupervised segmentation approach in colposcopy.

11 August 2022 in Expert Systems with Applications
Verified
Journal Article
Closed access
JPJinhee Park
Jinhee Park
SJSehyeon Jang
Sehyeon Jang
JGJeonghwan Gwak
Jeonghwan Gwak
BKByeong C. Kim
Byeong C. Kim
JLJang Jae Lee
Jang Jae Lee
SASangtae Ahn
Sangtae Ahn

30 June 2018 in KSII Transactions on Internet and Information Systems
Verified
Journal Article
Closed access
MLMinkyu Lim
Minkyu Lim
DLDonghyun Lee
Donghyun Lee
HPHosung Park
Hosung Park
YKYoseb Kang
Yoseb Kang
JOJunseok Oh
Junseok Oh
JKJin-Hoi Kim
Jin-Hoi Kim