Ching-Tai Chen

Prof. Ching-Tai Chen

Department of Computer Science, University of Taipei, Taipei, Taiwan
orcid
Lab website: https://sites.google.com/view/aiblab

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

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

Representative Publications

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4 November 2019 in Scientific Reports
Verified
Journal Article
Open access
TPThejkiran Pitti
Thejkiran Pitti
CCChing-Tai Chen
Ching-Tai Chen
HLHsin-Nan Lin
Hsin-Nan Lin
WCWai-Kok Choong
Wai-Kok Choong
WHWen-Lian Hsu
Wen-Lian Hsu
TSTing-Yi Sung
Ting-Yi Sung
N-linked glycosylation is one of the predominant post-translational modifications involved in a number of biological functions. Since experimental characterization of glycosites is challenging, glycosite prediction is crucial. Several predictors have been made available and report high performance. Most of them evaluate their performance at every asparagine in protein sequences, not confined to asparagine in the N-X-S/T sequon. In this paper, we present N-GlyDE, a two-stage prediction tool trained on rigorously-constructed non-redundant datasets to predict N-linked glycosites in the human proteome. The first stage uses a protein similarity voting algorithm trained on both glycoproteins and non-glycoproteins to predict a score for a protein to improve glycosite prediction. The second stage uses a support vector machine to predict N-linked glycosites by utilizing features of gapped dipeptides, pattern-based predicted surface accessibility, and predicted secondary structure. N-GlyDE’s final predictions are derived from a weight adjustment of the second-stage prediction results based on the first-stage prediction score. Evaluated on N-X-S/T sequons of an independent dataset comprised of 53 glycoproteins and 33 non-glycoproteins, N-GlyDE achieves an accuracy and MCC of 0.740 and 0.499, respectively, outperforming the compared tools. The N-GlyDE web server is available at http://bioapp.iis.sinica.edu.tw/N-GlyDE/.

25 January 2024 in Journal of Medical Internet Research
Verified
Journal Article
Open access
YLYou-Qian Lee
You-Qian Lee
CCChing-Tai Chen
Ching-Tai Chen
CCChien-Chang Chen
Chien-Chang Chen
CLChung-Hong Lee
Chung-Hong Lee
PCPeitsz Chen
Peitsz Chen
Hong-Jie DaiHong-Jie Dai
Hong-Jie Dai
Background: The widespread use of electronic health records in the clinical and biomedical fields makes the removal of protected health information (PHI) essential to maintain privacy. However, a significant portion of information is recorded in unstructured textual forms, posing a challenge for deidentification. In multilingual countries, medical records could be written in a mixture of more than one language, referred to as code mixing. Most current clinical natural language processing techniques are designed for monolingual text, and there is a need to address the deidentification of code-mixed text. Objective: The aim of this study was to investigate the effectiveness and underlying mechanism of fine-tuned pretrained language models (PLMs) in identifying PHI in the code-mixed context. Additionally, we aimed to evaluate the potential of prompting large language models (LLMs) for recognizing PHI in a zero-shot manner. Methods: We compiled the first clinical code-mixed deidentification data set consisting of text written in Chinese and English. We explored the effectiveness of fine-tuned PLMs for recognizing PHI in code-mixed content, with a focus on whether PLMs exploit naming regularity and mention coverage to achieve superior performance, by probing the developed models’ outputs to examine their decision-making process. Furthermore, we investigated the potential of prompt-based in-context learning of LLMs for recognizing PHI in code-mixed text. Results: The developed methods were evaluated on a code-mixed deidentification corpus of 1700 discharge summaries. We observed that different PHI types had preferences in their occurrences within the different types of language-mixed sentences, and PLMs could effectively recognize PHI by exploiting the learned name regularity. However, the models may exhibit suboptimal results when regularity is weak or mentions contain unknown words that the representations cannot generate well. We also found that the availability of code-mixed training instances is essential for the model’s performance. Furthermore, the LLM-based deidentification method was a feasible and appealing approach that can be controlled and enhanced through natural language prompts. Conclusions: The study contributes to understanding the underlying mechanism of PLMs in addressing the deidentification process in the code-mixed context and highlights the significance of incorporating code-mixed training instances into the model training phase. To support the advancement of research, we created a manipulated subset of the resynthesized data set available for research purposes. Based on the compiled data set, we found that the LLM-based deidentification method is a feasible approach, but carefully crafted prompts are essential to avoid unwanted output. However, the use of such methods in the hospital setting requires careful consideration of data security and privacy concerns. Further research could explore the augmentation of PLMs and LLMs with external knowledge to improve their strength in recognizing rare PHI.

7 February 2022 in Scientific Reports
Verified
Journal Article
Open access
PDF file
JWJen-Hung Wang
Jen-Hung Wang
WCWai-Kok Choong
Wai-Kok Choong
CCChing-Tai Chen
Ching-Tai Chen
TSTing-Yi Sung
Ting-Yi Sung
Identifying peptides and proteins from mass spectrometry (MS) data, spectral library searching has emerged as a complementary approach to the conventional database searching. However, for the spectrum-centric analysis of data-independent acquisition (DIA) data, spectral library searching has not been widely exploited because existing spectral library search tools are mainly designed and optimized for the analysis of data-dependent acquisition (DDA) data. We present Calibr, a spectral library search tool for spectrum-centric DIA data analysis. Calibr optimizes spectrum preprocessing for pseudo MS2 spectra, generating an 8.11% increase in spectrum–spectrum match (SSM) number and a 7.49% increase in peptide number over the traditional preprocessing approach. When searching against the DDA-based spectral library, Calibr improves SSM number by 17.6–26.65% and peptide number by 18.45–37.31% over two state-of-the-art tools on three different data sets. Searching against the public spectral library from MassIVE, Calibr improves state-of-the-art tools in SSM and peptide numbers by more than 31.49% and 25.24%, respectively, for two data sets. Our analyses indicate higher sensitivity of Calibr results from the use of various spectral similarity measures and statistical scores, coupled with machine learning-based statistical validation for FDR control. Calibr executable files including a graphical user-interface application are available at https://ms.iis.sinica.edu.tw/COmics/Software_CalibrWizard.html and https://sourceforge.net/projects/comics-calibr.

29 October 2008 in Bioinformatics
Verified
Journal Article
Open access
PDF file
CCChing-Tai Chen
Ching-Tai Chen
EYEi-Wen Yang
Ei-Wen Yang
HHHung-Ju Hsu
Hung-Ju Hsu
YSYi-Kun Sun
Yi-Kun Sun
WHWen-Lian Hsu
Wen-Lian Hsu
AYAn-Suei Yang
An-Suei Yang
Motivation: Regulatory proteases modulate proteomic dynamics with a spectrum of specificities against substrate proteins. Predictions of the substrate sites in a proteome for the proteases would facilitate understanding the biological functions of the proteases. High-throughput experiments could generate suitable datasets for machine learning to grasp complex relationships between the substrate sequences and the enzymatic specificities. But the capability in predicting protease substrate sites by integrating the machine learning algorithms with the experimental methodology has yet to be demonstrated. Results: Factor Xa, a key regulatory protease in the blood coagulation system, was used as model system, for which effective substrate site predictors were developed and benchmarked. The predictors were derived from bootstrap aggregation (machine learning) algorithms trained with data obtained from multilevel substrate phage display experiments. The experimental sampling and computational learning on substrate specificities can be generalized to proteases for which the active forms are available for the in vitro experiments. Availability:http://asqa.iis.sinica.edu.tw/fXaWeb/ Contact:hsu@iis.sinica.edu.tw; yangas@gate.sinica.edu.tw Supplementary information: Supplementary data are available at Bioinformatics online.

14 April 2026 in medRxiv
Verified
Preprint
Open access
PDF file
Hong-Jie DaiHong-Jie Dai
Hong-Jie Dai
HLHang T.B. Le
Hang T.B. Le
LFLiang-Chun Fang
Liang-Chun Fang
TMTatheer Hussain Mir
Tatheer Hussain Mir
CCChing-Tai Chen
Ching-Tai Chen
JJJitendra Jonnagaddala
Jitendra Jonnagaddala
Transcript-based de-identification protects textual records but leaves sensitive health information (SHI) directly audible in source recordings, limiting trustworthy reuse of clinical audio. However, standardized evaluations of recording-level SHI detection remain limited. We established the SREDH-AICUP 2025 benchmark to evaluate recording-level SHI detection systems and characterize the approaches. All 22 qualifying systems combined automatic speech recognition with downstream SHI detection, whereas we additionally evaluated end-to-end detection from audio. Pipeline baselines outperformed the end-to-end baseline in transcription (MER, 0.123 vs 0.155) and SHI detection (macro-F1, 0.507-0.653 vs 0.422). Synthetic Mandarin speech-text augmentation enabled the end-to-end model to detect Mandarin SHI that was not identified without augmentation (macro-F1, 0.171 vs 0). Foundation models showed category-specific differences in SHI recognition, and type-aware adaptive routing improved macro-F1 from 0.656 to 0.697. These findings establish standardized reference performance, characterize current system designs, and demonstrate how language-specific augmentation and category-aware model integration can improve recording-level SHI detection.

15 July 2019 in Analytical Chemistry
Verified
Journal Article
Closed access
CCChing-Tai Chen
Ching-Tai Chen
CKChu-Ling Ko
Chu-Ling Ko
WCWai-Kok Choong
Wai-Kok Choong
JWJen-Hung Wang
Jen-Hung Wang
WHWen-Lian Hsu
Wen-Lian Hsu
TSTing-Yi Sung
Ting-Yi Sung