Chin-Cho Pai

Dr. Chin-Cho Pai


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

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

Representative Publications

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18 April 2022 in Applied Sciences
Verified
Journal Article
Open access
PDF file
Pi-Yun ChenPi-Yun Chen
Pi-Yun Chen
XZXuan-Hao Zhang
Xuan-Hao Zhang
Jian-Xing WuJian-Xing Wu
Jian-Xing Wu
CPChin-Cho Pai
Chin-Cho Pai
JHJin-Chyr Hsu
Jin-Chyr Hsu
Neng-Sheng PaiNeng-Sheng Pai
Neng-Sheng Pai
Mammography is a first-line imaging examination approach used for early breast tumor screening. Computational techniques based on deep-learning methods, such as convolutional neural network (CNN), are routinely used as classifiers for rapid automatic breast tumor screening in mammography examination. Classifying multiple feature maps on two-dimensional (2D) digital images, a multilayer CNN has multiple convolutional-pooling layers and fully connected networks, which can increase the screening accuracy and reduce the error rate. However, this multilayer architecture presents some limitations, such as high computational complexity, large-scale training dataset requirements, and poor suitability for real-time clinical applications. Hence, this study designs an optimal multilayer architecture for a CNN-based classifier for automatic breast tumor screening, consisting of three convolutional layers, two pooling layers, a flattening layer, and a classification layer. In the first convolutional layer, the proposed classifier performs the fractional-order convolutional process to enhance the image and remove unwanted noise for obtaining the desired object’s edges; in the second and third convolutional-pooling layers, two kernel convolutional and pooling operations are used to ensure the continuous enhancement and sharpening of the feature patterns for further extracting of the desired features at different scales and different levels. Moreover, there is a reduction of the dimensions of the feature patterns. In the classification layer, a multilayer network with an adaptive moment estimation algorithm is used to refine a classifier’s network parameters for mammography classification by separating tumor-free feature patterns from tumor feature patterns. Images can be selected from a curated breast imaging subset of a digital database for screening mammography (CBIS-DDSM), and K-fold cross-validations are performed. The experimental results indicate promising performance for automatic breast tumor screening in terms of recall (%), precision (%), accuracy (%), F1 score, and Youden’s index.

25 April 2022 in Electronics
Verified
Journal Article
Open access
PDF file
Chia-Hung LinChia-Hung Lin
Chia-Hung Lin
FZFeng-Zhou Zhang
Feng-Zhou Zhang
Jian-Xing WuJian-Xing Wu
Jian-Xing Wu
Neng-Sheng PaiNeng-Sheng Pai
Neng-Sheng Pai
Pi-Yun ChenPi-Yun Chen
Pi-Yun Chen
CKChung-Dann Kan
Chung-Dann Kan
Palpitations, chest tightness, and shortness of breath are early indications of cardiomegaly, which is an asymptomatic disease. Their causes and treatment strategies are different due to differing indications. Hence, early screening of cardiomegaly levels can be used to make a strategy for administering drugs and surgical treatments. In this study, we will establish a multilayer one-dimensional (1D) convolutional neural network (CNN)-based classifier for automatic cardiomegaly level screening based on chest X-ray (CXR) image classification in frontal posteroanterior view. Using two-round 1D convolutional processes in the convolutional pooling layer, two-dimensional (2D) feature maps can be converted into feature signals, which can enhance their characteristics for identifying normal condition and cardiomegaly levels. In the classification layer, a classifier based on gray relational analysis, which has a straightforward mathematical operation, is used to screen the cardiomegaly levels. Based on the collected datasets from the National Institutes of Health CXR image database, the proposed multilayer 1D CNN-based classifier with K-fold cross-validation has promising results for the intended medical purpose, with precision of 97.80%, recall of 98.20%, accuracy of 98.00%, and F1 score of 0.9799.

15 September 2022 in Processes
Verified
Journal Article
Open access
PDF file
FZFeng-Zhou Zhang
Feng-Zhou Zhang
Chia-Hung LinChia-Hung Lin
Chia-Hung Lin
Pi-Yun ChenPi-Yun Chen
Pi-Yun Chen
Neng-Sheng PaiNeng-Sheng Pai
Neng-Sheng Pai
CSChun-Min Su
Chun-Min Su
HHHui-Wen Ho
Hui-Wen Ho
Mammography is a low-dose X-ray imaging technique that can detect breast tumors, cysts, and calcifications, which can aid in detecting potential breast cancer in the early stage and reduce the mortality rate. This study employed a multilayer convolutional neural network (MCNN) to screen breast lesions with mammographic images. Within the region of interest, a specific bounding box is used to extract feature maps before automatic image segmentation and feature classification are conducted. These include three classes, namely, normal, benign tumor, and malignant tumor. Multiconvolution processes with kernel convolution operations have noise removal and sharpening effects that are better than other image processing methods, which can strengthen the features of the desired object and contour and increase the classifier’s classification accuracy. However, excessive convolution layers and kernel convolution operations will increase the computational complexity, computational time, and training time for training the classifier. Thus, this study aimed to determine a suitable number of convolution layers and kernels to achieve a classifier with high learning performance and classification accuracy, with a case study in the breast lesion screening of mammographic images. The Mammographic Image Analysis Society Digital Mammogram Database (United Kingdom National Breast Screening Program) was used for experimental tests to determine the number of convolution layers and kernels. The optimal classifier’s performance is evaluated using accuracy (%), precision (%), recall (%), and F1 score to test and validate the most suitable MCNN model architecture.

22 November 2021 in Processes
Verified
Journal Article
Open access
PDF file
Pi-Yun ChenPi-Yun Chen
Pi-Yun Chen
Chia-Hung LinChia-Hung Lin
Chia-Hung Lin
Jian-Xing WuJian-Xing Wu
Jian-Xing Wu
CPChin-Cho Pai
Chin-Cho Pai
CLChien-Ming Li
Chien-Ming Li
Neng-Sheng PaiNeng-Sheng Pai
Neng-Sheng Pai
Common upper limb peripheral artery diseases (PADs) are atherosclerosis, embolic diseases, and systemic diseases, which are often asymptomatic, and the narrowed arteries (stenosis) will gradually reduce blood flow in the right or left upper limbs. Upper extremity vascular disease (UEVD) and atherosclerosis are high-risk PADs for patients with Type 2 diabetes or with both diabetes and end-stage renal disease. For early UEVD detection, a fingertip-based, toe-based, or wrist-based photoplethysmography (PPG) tool is a simple and noninvasive measurement system for vital sign monitoring and healthcare applications. Based on time-domain PPG analysis, a Duffing–Holmes system with a master system and a slave system is used to extract self-synchronization dynamic errors, which can track the differences in PPG morphology (in amplitudes (systolic peak) and time delay (systolic peak to diastolic peak)) between healthy subjects and PAD patients. In the preliminary analysis, the self-synchronization dynamic errors can be used to evaluate risk levels based on the reflection index (RI), which includes normal condition, lower PAD, and higher PAD. Then, a one-dimensional convolutional neural network is established as a multilayer classifier for automatic UEVD screening. The experimental results indicated that the self-synchronization dynamic errors have a positive correlation with the RI (R2 = 0.6694). The K-fold cross-validation is used to verify the performance of the proposed classifier with recall (%), precision (%), accuracy (%), and F1 score.

26 July 2022 in Applied Sciences
Verified
Journal Article
Open access
PDF file
Chia-Hung LinChia-Hung Lin
Chia-Hung Lin
HLHsiang-Yueh Lai
Hsiang-Yueh Lai
Pi-Yun ChenPi-Yun Chen
Pi-Yun Chen
Jian-Xing WuJian-Xing Wu
Jian-Xing Wu
CPChin-Cho Pai
Chin-Cho Pai
HHHui-Wen Ho
Hui-Wen Ho
Mammography is a first-line imaging examination that employs low-dose X-rays to rapidly screen breast tumors, cysts, and calcifications. This study proposes a two-dimensional (2D) spatial and one-dimensional (1D) convolutional neural network (CNN) to early detect possible breast lesions (tumors) to reduce patients’ mortality rates and to develop a classifier for use in mammographic images on regions of interest where breast lesions (tumors) may likely occur. The 2D spatial fractional-order convolutional processes are used to strengthen and sharpen the lesions’ features, denoise, and improve the feature extraction processes. Then, an automatic extraction task is performed using a specific bounding box to sequentially pick out feature patterns from each mammographic image. The multi-round 1D kernel convolutional processes can also strengthen and denoise 1D feature signals and assist in the identification of the differentiation levels of normality and abnormality signals. In the classification layer, a gray relational analysis-based classifier is used to screen the possible lesions, including normal (Nor), benign (B), and malignant (M) classes. The classifier development for clinical applications can reduce classifier’s training time, computational complexity level, computational time, and achieve a more accurate rate for meeting clinical/medical purpose. Mammographic images were selected from the mammographic image analysis society image database for experimental tests on breast lesions screening and K-fold cross-validations were performed. The experimental results showed promising performance in quantifying the classifier’s outcome for medical purpose evaluation in terms of recall (%), precision (%), accuracy (%), and F1 score.

28 February 2022 in Medicina
Verified
Journal Article
Open access
PDF file
YNYa-Lei Niu
Ya-Lei Niu
NMN. Patrick Mayr
N. Patrick Mayr
YCYing-Hwa Chen
Ying-Hwa Chen
HCHsiao-Huang Chang
Hsiao-Huang Chang
SWShi-Pu Wang
Shi-Pu Wang
CPChin-Cho Pai
Chin-Cho Pai
Transcatheter aortic valve implantation (TAVI) has evolved to be the treatment of choice for patients with severe aortic stenosis and high perioperative risk. Cardiogenic shock is one of the most severe complications during the TAVI procedure, especially as the prognosis of cardiogenic shock secondary to aortic stenosis is very poor. This situation can be challenging, while extracorporeal membranous oxygenation (ECMO) can be a treatment option. Here, we reported on an 88-year-old female patient who had been diagnosed as non-ST-elevation myocardial infarction (NSTEMI) and critical aortic valve stenosis (AS) with a logistic Euroscore of 25%. Percutaneous coronary angioplasty (PCI) was performed smoothly and developed tachy-brady arrhythmia of atrial fibrillation then cardiac arrest at the beginning of the TAVI procedure. A v-a ECMO was installed at her left femoral side. Afterward, the TAVI procedure was completed accordingly; her consciousness recovered and Levosimendan therapy enhanced her left-ventricular ejection fraction (LVEF) from 22% to 40%. Five days after TAVI, ECMO was replaced by intra-aortic balloon pumping (IABP) and it was removed 3 days later. A minor complication of this therapy, e.g., muscular weakness in her left leg, was noted. The patient underwent rehabilitation for about 2 months, and was discharged from hospital with a wheel chair and clear consciousness. At the 24 month follow-up she was in good recovery and was able to walk upstairs to the second floor again. Our experience suggests that one indication of prophylactic use of ECMO is for patients with an unstable hemodynamic condition.