April 30, 2020
Dr. P. Vijayalakshmi – Professor & Head
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Dr. P. Vijayalakshmi, (IEEE M ’08-15, SM ’16 onwards) (Member IEEE Signal Processing Society) (Fellow IETE) Professor and Head in the Department of Electronics and Communication Engineering, has 27 years of teaching and research experience, including 4 years of exclusive research experience in the field of Speech signal processing.
Education
Dr. P. Vijayalakshmi received B.E (ECE) degree first class with distinction from Bharathidasan University. She Completed M.E (Communication systems) from Regional Engineering College, Trichy (currently NIT, Trichy) and earned her Ph.D. degree from IIT Madras and worked as a doctoral trainee for a year at INRS – EMT, Montreal, Canada.
During her Ph.D she developed various speech recognition systems and a novel approach for detection and assessment of disordered speech such as hypernasal and dysarthric speech apart from analyzing normal speech. During her Ph.D she had an opportunity to work with Prof. Douglas O’Shaughnessy at National Institute of Scientific Research (INRS), Montreal, Canada as a doctoral trainee for a period of one year in a project titled “Speech recognition and analysis”.
Research
She has published over 100 research publications in refereed international journals and in proceedings of international conferences. As a principal investigator she is currently involved in MeiTy funded project titled “speech Assistive Technologies” – NLTM- Bhashini. and completed DST-TIDE funded project. As a co- investigator she has completed projects funded by DeitY, MCIT, New Delhi, and Tamil Virtual Academy, a Government of Tamil Nadu organization, and two projects funded by SSN Trust. She is a recognized supervisor of Anna University and currently guiding three fulltime Ph.D scholars in the field of speech technology.
Her areas of research include speech enhancement, statistical parametric speech synthesis and speech enabled assistive technology, voice conversion, polyglot speech synthesis, speech recognition.
Dr. P. Vijayalakshmi is a AICTE nominated Margdarshak under Margdarshan scheme to mentor Institutes for NBA accreditation.
Patents
- Vijayalakshmi, N.Naren Raju and V. Aishwarya have submitted First examination report (FER) for a patent titled “Hidden Markov model-based sign language-to-speech conversion system in Tamil” in the Indian Patent office in July 2022. (Reference number: 201841038594)
- Vijayalakshmi, T. Nagarajan and T.A. MariyaCelin have submitted FER for a patent titled “A Speech-input Speech-output Communication Aid for Speakers with Cerebral Palsy” in the Indian Patent office in July 2022. (Reference number: 201941031287)
Book Chapters
2. Vijayalakshmi, T. A. Mariya Celin, T. Nagarajan, “Selective pole modification-basedtechnique for the analysis and detection of hypernasality”, Chapter 2 – Signal and Acoustic Modeling for Speech and Communication Disorders, De Gruyter Series in Speech Technology and Text Mining in Medicine and Healthcare, pp. 33 – 68, Dec. 2018.
Selected Journal Publications
- Mrinalini K, Vijayalakshmi and T. Nagarajan, “SBSim: A sentence BERT Similarity based evaluation metric for Indian language neural machine translation systems” – IEEE/ACM Transactions on Audio, Speech and Language Processing, Vol. 30, pp. 1396 – 1406, March 2022
- Lavanya, T. Nagarajan and P. Vijayalakshmi, “Multi-level single-channel speech enhancement using a unified framework for estimating magnitude and phase spectra” – IEEE/ACM Transactions on Audio, Speech and Language Processing, Vol. 28, pp. 1315 – 1327, Apr.2020
- Mrinalini, T. Nagarajan, P. Vijayalakshmi, “Pause-Based Phrase Extraction and Effective OOV Handling for Low-Resource Machine Translation Systems”, ACM Transactions on Asian and Low Resource Language Information Processing, Vol. 18, Issue 2, pp. 12:1-12:22, Feb 2019.
- Vijayalakshmi, M. R. Reddy and Douglas O’Shaughnessy – “Acoustic Analysis and detection of hycalpernasality using group delay function” – IEEE Transactions on Biomedical Engineering, Vol.54, No. 4, pp 621 – 629, April 2007.
- Mariya Celin, T.A, Nagarajan T and Vijayalakshmi, “ Data Augmentation using virtual microphone array synthesis and multi-resolution feature extraction for isolated word dysarthric speech recognition”, IEEE Journal of selected topics on signal processing, Vol. 14, No. 2, pp. 346 – 354, Feb. 2020.
- A. MariyaCelin, G. Anushiya Rachel, T. Nagarajan, P. Vijayalakshmi, “A Weighted Speaker-Specific Confusion Transducer Based Augmentative and Alternative Speech Communication Aid for Dysarthric Speakers”, IEEE Transactions on Neural Systems and Rehabilitation Engineering, Vol. 27, Issue 2, pp. 187-197, Feb 2019.
- Mrinalini K, Vijayalakshmi P, Nagarajan T, “Feature-weighted AdaBoost classifier for punctuation prediction in Tamil and Hindi NLP systems”, Expert Systems, Wiley, pp. 1 – 19, Dec. 2021.
- Vijayalakshmi, Nagarajan, T., Jayapriya, R, Brathindara, S., Krithika, K., Nikhilesh, N. Naren Raju, N. Johanan Joysingh, S., Aiswarya, V. Mrinalini, K., “Development of a low-resource wearable continuous gesture-to-speech conversion system”, Disability and Rehabilitation: Assistive Technology. pp.1 – 13, Jan. 2022.
- Dhanalakshmi, T. Nagarajan, P. Vijayalakshmi, ‘Significant sensors and parameters in assessment of dysarthric speech’, Sensor Review, Vol. 41 No. 3, pp. 271-286, July 2021.
- P. Actlin Jeeva, T. Nagarajan, P. Vijayalakshmi, “Adaptive Multi-Band Filter Structure-based Far-End Speech Enhancement”, IET Signal Processing, Vol. 14, Issue 5 pp. 288 – 299, Jun. 2020.
- Anushiya Rachel, P. Vijayalakshmi, T. Nagarajan, “Estimation of Glottal Closure Instants from Degraded Speech using a Phase-Difference-Based Algorithm”, Computer, Speech, and Language, Vol. 46, pp. 136 – 153, Nov. 2017.
- SherlinSolomi, P. Vijayalakshmi, T. Nagarajan, “Exploiting Acoustic Similarities Between Tamil and Indian English in the Development of an HMM-based Bilingual Synthesizer”, IET Signal Processing, Vol. 11, Issue 3, pp. 332-340, May 2017.
- P. Actlin Jeeva, T. Nagarajan, P. Vijayalakshmi, “DCT derived spectrum-based speech enhancement algorithm using temporal-domain multiband filtering”, IET Signal Processing, pp. 965-980, Vol. 10, Issue 8, Oct. 2016.
- Anushiya Rachel, Sreenidhi, Vijayalakshmi and T. Nagarajan, “Incorporation of happiness in neutral speech by modifying time-domain parameters of emotive keywords”, Circuits, systems and signal processing, 2022, Vol. 41, pp. 2061 – 2087, Mar. 2022
- Nanmalar, P. Vijayalakshmi, T. Nagarajan, “Literary and colloquial Tamil dialect identification”, Circuits, systems and signal processing, 2022. pp. 1- 24, DOI: -10.1007/s00034-022-01971-2.
- Maria Celin T. A., P. Vijayalakshmi and T. Nagarajan, “Data Augmentation Techniques for Transfer Learning-based continuous dysarthric speech recognition”, Circuits, systems and signal processing, pp. 1 – 22, Aug. 2022
- Johanan Joysingh S., P. Vijayalakshmi and T. Nagarajan, “Chirp Group Delay based Onset Detection in Instruments with Fast Attack” Circuit systems and signal processing, pp. 1- 24, Sep. 2022.
Consultancy Project
Title: Improving speech visualization through signal processing techniques
Company: 4S Medical Research, NewDelhi
Consultants: Dr. P. Vijayalakshmi, Dr. T. Nagarajan
Amount sanctioned – 2.74 lakh
External Funded Research Projects
1. Title : Speech Assistive Technologies
Funding Agency: MeiTy, Government of India, A Consortium Project with IITM as leaders)
Project investigators: Dr. P. Vijayalakshmi (PI) and Dr. T. Nagarajan (Co-PI)
Duration: 3 years, Apr. 2022 – Mar. 2025
Sanctioned amount: 85.26 lakh
Status: Ongoing
2. Title : Prosody Modelling
Funding Agency: MeiTy, Government of India, consortium leader – IITM)
Project investigators: Dr. T. Nagarajan (PI) and Dr. P. Vijayalakshmi (Co-PI)
Duration: 3 years, Apr. 2022 – Mar. 2025
Sanctioned amount: 99 lakh
Status: Ongoing
3. Title : Speech-Input speech-output communication Aid (SISOCA) for speakers with cerebral palsy
Funding Agency: DST-TIDE
Project investigators: Dr. P. Vijayalakshmi (PI) and Dr. T. Nagarajan (Co-PI)
Duration: 3 years, Mar. 2017 – Mar 2020
Sanctioned amount: 13. 72 lakh
Status: Completed
4. Title: HMM-based Text-to-Speech Synthesis System for Malaysian Tamil
Funding Agency: Murasu Systems Sdn Bhd, Malaysia
Project Investigators: Dr. T. Nagarajan (PI), Dr. P. Vijayalakshmi (Co-PI)
Duration: one year, from Nov. 2016 to Oct. 2017.
Total funding: 4 lakh
Status: Completed
5. Title: Development of Text-to-Speech Synthesis Systems for Indian Languages – high quality TTS and small footprint TTS integrated with disability aids, (A consortium Project with IITM as leader)
Funding Agency: Department of Electronics and Information Technology (DeitY)
Project Investigator: Dr. T. Nagarajan (PI), Dr. P. Vijayalakshmi (Co-PI)
Duration: March 2012 –June 2018
Total funding: Rs. 77 lakh for SSNCE and 12.66 crore for the consortium
Status: Completed
6. Title: Speech enabled interactive enquiry system in Tamil
Funding Agency:Tamil Virtual Academy, Chennai
Project Investigators: Dr. T. Nagarajan (PI), Dr. P. Vijayalakshmi (Co-PI), Dr. B.Bharathi , Sasirekha (CoPI)
Duration: Mar. 2016 – Mar. 2017
Sanctioned amount: Rs. 9.52 lakh
Status: Completed
7. Title: Tamil Pronunciation error detection for children – Prototype
Funding agency: Murasu systems Sdn Bhd, Malaysia
Investigators: Dr. T. Nagarajan, Dr. P. Vijayalakshmi
Duratoin: Aug. 2019 – Sep. 2019
Sanction amount: 0.5 lakh
Status: Completed
8. Title: Speech Assistive Aids for Visually-challenged people
Funding agency: Tamil Virtual Academy (TVA), Chennai
Investigators: Dr. T. Nagarajan, Dr. P. Vijayalakshmi
Status: Completed
Duration: Aug. 2018 – Aug. 2019
Sanctioned Amount: 25 lakh
9. Title: An assessment and intelligibility modification system for dysarthric speakers
FundingAgency: AICTE-RPS (A), New Delhi
Investigators: Dr. P. Vijayalakshmi and Dr. T. Nagarajan
Status: Completed
Duration: 2010 – 2012
Amount: Rs. 9 lakh
10. Title: Design of lab model of speech processor for cochlear implants
Funding Agency: SSN Trust
Investigators: Dr. P. Vijayalakshmi, Dr. T. Nagarajan & Dr. A. Shahina
Status: Completed
Duration: 2010 – 2012
Amount: Rs. 0.8 lakh
11. Title: Anatomical vibration sensor speech corpus for speech applications in noisy environments.
Funding Agency: SSN Trust
Investigators: Dr. A. Shahina, Dr. T. Nagarajan & Dr. P. Vijayalakshmi
Status: Completed
Duration: 2010 – 2012
Amount: Rs. 1.23 lakh
Ph.D guidance:
Completed:
- Ramani, “Multilingual to polyglot speech synthesis system for Indian languages by sharing common attributes”, Part time. – Completed
- Dhanalakshmi, “An Assessment and Intelligibility modification system for Dysarthric speakers”, Part time. Completed
- P. ActlinJeeva, “Dynamic Multi-Band Filter Structures for Simultaneous Improvement of Speech Quality and Intelligibility”, Full time – Completed
- Mrinalini, “Development and evaluation of hybrid machine translation systems for english-to-Indian Language under low resource conditions”, Full time – Completed
- A. MariyaCelin, “Development of an Augmentative and Alternative speech Communication aid for Dysarthric Speakers”, Full time – Completed
- Anushiya Rachel, “A robust phase-difference-based approach to the estimation of glottal closure instants and its applications”, Full time – Completed
- Sherlin Solomi V, “Development of an HMM-based bilingual synthesizer for Tamil and Indian English by merging acoustically similar phonemes” – Full time – Completed
Ongoing:
- Lavanya, “Maintaining Speech Intelligibility in Challenging Conditions”, Full time – On going
- Johanan Joysingh, “ Chirp-Group delay and Applications” – Ongoing
- Nanmalar – “Colloquial and Literary Tamil ASRs” – Ongoing
Research Guidance:
Guided: Around 25 M.E thesis and more than 30 UG projects
Web links:
Google scholar citations: https://scholar.google.com/citations?hl=en&user=CRBglkoAAAAJ
Linkedin URL: https://www.linkedin.com/in/vijayalakshmi-nagarajan-83806b18/
Research gate: https://www.researchgate.net/profile/P_Vijayalakshmi