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Publication Title : HMM-based speech synthesis system for Malay: a comparison of iterative and isolated unit training.
Author : Dr. Mumtaz Begum Binti Peer Mustafa
Prof. Dr. Zuraidah Binti Mohd Don
Publisher URL : http://search.ieice.org/bin/summary.php?id=e97-d_5_1273&category=D&lang=E&ref=rss&abst=&year=2014

Publication Abstract:
The development of an HMM-based speech synthesis system for a new language requires resources like speech database and segment-phonetic labels. As an under-resourced language, Malay lacks the necessary resources for the development of such a system, especially segment-phonetic labels. This research aims at developing an HMM-based speech synthesis system for Malay. We are proposing the use of two types of training HMMs, which are the benchmark iterative training incorporating the DAEM algorithm and isolated unit training applying segment-phonetic labels of Malay. The preferred method for preparing segment-phonetic labels is the automatic segmentation. The automatic segmentation of Malay speech database is performed using two approaches which are uniform segmentation that applies fixed phone duration, and a cross-lingual approach that adopts the acoustic model of English. We have measured the segmentation error of the two segmentation approaches to ascertain their relative effectiveness. A listening test was used to evaluate the intelligibility and naturalness of the synthetic speech produced from the iterative and isolated unit training. We also compare the performance of the HMM-based speech synthesis system with existing Malay speech synthesis systems.

Publication Title : Severity-based adaptation with limited data for ASR to aid dysarthric speakers
Author : Dr. Mumtaz Begum Binti Peer Mustafa
Publisher URL : http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0086285

Publication Abstract:
Automatic speech recognition (ASR) is currently used in many assistive technologies, such as helping individuals with speech impairment in their communication ability. One challenge in ASR for speech-impaired individuals is the difficulty in obtaining a good speech database of impaired speakers for building an effective speech acoustic model. Because there are very few existing databases of impaired speech, which are also limited in size, the obvious solution to build a speech acoustic model of impaired speech is by employing adaptation techniques. However, issues that have not been addressed in existing studies in the area of adaptation for speech impairment are as follows: (1) identifying the most effective adaptation technique for impaired speech; and (2) the use of suitable source models to build an effective impaired-speech acoustic model. This research investigates the above-mentioned two issues on dysarthria, a type of speech impairment affecting millions of people. We applied both unimpaired and impaired speech as the source model with well-known adaptation techniques like the maximum likelihood linear regression (MLLR) and the constrained-MLLR(C-MLLR). The recognition accuracy of each impaired speech acoustic model is measured in terms of word error rate (WER), with further assessments, including phoneme insertion, substitution and deletion rates. Unimpaired speech when combined with limited high-quality speech-impaired data improves performance of ASR systems in recognising severely impaired dysarthric speech. The C-MLLR adaptation technique was also found to be better than MLLR in recognising mildly and moderately impaired speech based on the statistical analysis of the WER. It was found that phoneme substitution was the biggest contributing factor in WER in dysarthric speech for all levels of severity. The results show that the speech acoustic models derived from suitable adaptation techniques improve the performance of ASR systems in recognising impaired speech with limited adaptation data.

Publication Title : Transitional Justice and Peacebuilding in Africa: Nexus or Nemesis?
Author : Dr. Muhamad Danial Bin Azman
Publisher URL : - none -

Publication Abstract:
In what way have liberal peacebuilding interacted with the mechanisms commonly associated with Transitional Justice (TJ), and how has this enriched the debate of liberal peace and democracy in Africa? In two parts, this article briefly elucidates the intersection between Transitional Justice (TJ) and liberal peacebuilding. The first part begins by revising Oliver Richmond's four generations of practices in peacebuilding. A particular emphasis will be placed here on the fourth, most contemporary framework for liberal peacebuilding, and major criticisms that it has received in Africa. The second part acknowledges the sustained criticism of liberal peace in Africa, which is key to understanding the growing relevance of the 'justice versus peace' debate in two specific forms of post-conflict reconstruction experiments in Africa, Two are: (i) transformation from peacekeeping to peace building; (ii) a paradigm shift from the normative, liberal peace conviction that justice is a good project, to a legal consequentialist argument that peace cannot be lastingly sustained without some form of criminal prosecution, resulting the increasing usage of human rights language in drafting peace agreements. The aims is to highlight the deeper affinity and deficiency that can be viewed as two sides of the same coin in the liberal cosmopolitan approach to post-Cold War International Relations (IR): peacebuilding as a political project that concerned with sustainable peace, and TJ as a legal project that concerns itself with evaluating the modes of justice during the transitional phase.

Publication Title : The Safety and Strength of a Novel Medial, Partial Non- Threaded Pedicle Screw: A Cadaveric and Biomechanical Investigation
Author : Dr. Rukmanikanthan A/L Shanmugam
Publisher URL : http://journals.lww.com/jspinaldisorders/Pages/default.aspx

Publication Abstract:
STUDY DESIGN:: Cadaveric and biomechanical study. OBJECTIVE:: Assess the safety and pullout strength of medial, partial non-threaded thoracic pedicle screws compared to conventional screws. SUMMARY OF BACKGROUND DATA:: The perforation rate of pedicle screws has been reported as high as 41%. Nerve injury and irritation can result from compression of malpositioned screw on neural structures. METHODS:: Ten fresh cadavers were studied. 5.0 mm and 6.0 mm screws were inserted from T1-T6 and T7-T12 respectively. Pedicle perforations and fractures were recorded upon screw insertion and final positioning (non-threaded portion facing medially) following a wide laminectomy. Pullout strength of novel and conventional screws were then tested using an Instron machine in an artificial bone substitute. RESULTS:: 240 thoracic pedicle screws were inserted. 88.8% (213 screws) were fully contained during screw insertion. There were 5.0% (12 screws) Grade 1 medial perforations and 6.2% (15 screws) Grade 1 lateral perforations during screw insertion. Upon final positioning, 93.8% (225 screws) were fully contained. All Grade 1 medial perforations, which occurred during insertion, were converted to Grade 0. No dural or nerve root injuries occurred. Pedicle split fractures were noted in 6.7% (16 screws). The use of medial, partial non-threaded screws reduced the overall perforation rate from 11.2% to 6.2%. The mean pullout load for the 5 mm fully threaded screw vs. medial, partial non-threaded was 1419.3 N±106.1 (1275.8-1538.8 N) and 1336.6 N±44.2 (1293.0-1405.1 N) respectively, whereas 6 mm pullout load averaged 2126.0 N±134.8 (1986.3-2338.3 N) and 2036.5 N±210.0 (1818.4-2355.9 N). The difference was not statistically significant. CONCLUSION:: The use of medial, partial non-threaded pedicle screws reduced the medial perforation rate from 5.0% to 0%; however, pullout strength was not significantly reduced. The use of this novel screw can potentially reduce the incidence of nerve injury or irritation following medial pedicle perforations.

Publication Title : The Use of X-Shaped Cross-Link in Posterior Spinal Constructs Improves Stability in Thoracolumbar Burst Fracture: A Finite Element Analysis
Author : Dr. Murali Malliga Raman
Publisher URL : http://onlinelibrary.wiley.com/doi/10.1002/jor.22376/abstract;jsessionid=42F8308177CD31DC29F562BC5D7DDC59.f02t02

Publication Abstract:
Posterior instrumentation is a common fixation method used to treat thoracolumbar burst fractures. However, the role of different cross-link configurations in improving fixation stability in these fractures has not been established. A 3D finite element model of T11-L3 was used to investigate the biomechanical behavior of short (2 level) and long (4 level) segmental spine pedicle screw fixation with various cross-links to treat a hypothetical L1 vertebra burst fracture. Three types of cross-link configurations with an applied moment of 7.5 Nm and 200 N axial force were evaluated. The long construct was stiffer than the short construct irrespective of whether the cross-links were used (p < 0.05). The short constructs showed no significant differences between the cross-link configurations. The XL cross-link provided the highest stiffness and was 14.9% stiffer than the one without a cross-link. The long construct resulted in reduced stress to the adjacent vertebral bodies and screw necks, with 66.7% reduction in bending stress on L2 when the XL cross-link was used. Thus, the stability for L1 burst fracture fixation was best achieved by using long segmental posterior instrumentation constructs and an XL cross-link configuration. Cross-links did not improved stability when a short structure was used.

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