Mokhtar Harun

The use of graphic rules in grade one to help identify children at risk of handwriting difficulties.

Previous researches on elementary grade handwriting revealed that pupils employ certain strategy when writing or drawing. The relationship between this strategy and the use of graphic rules has been documented but very little research has been devoted to the connection between the use of graphic rules and handwriting proficiency. Thus, this study was conducted to investigate the relative contribution of the use of graphic rules to the writing ability. A sample of 105 first graders who were average printers and 65 first graders who might experience handwriting difficulty, as judged by their teachers, of a normal primary school were individually tested on their use of graphic rules. It has been found that pupils who are below average printers use more non-analytic strategy than average printers to reproduce the figures. The results also reveal that below average printers do not acquire the graphic principles that foster an analytic approach to production skills. Although the findings are not sufficient to allow definitive conclusions about handwriting ability, it can be considered as one of the screening measures in identifying pupils who are at risk of handwriting difficulties.

Identification of phoneme and its distribution of malay language derived from Friday sermon transcripts

Lack of text data is one of the main issues encountered by Malay speech researchers. Currently, there are few established Malay text corpora to aid in their research. Text corpora are essential due to its ability to provide empirical data for researchers in the field of linguistics and are useful to construct word lists for speech intelligibility test, speech analysis across genders and automatic speech recognition. The text corpora also need to mimic the natural phoneme of the language it represents. To accomplish this, we need to know the phonetic distribution of the language. The purpose of this research is to devise a phoneme distribution for the Malay language based on the transcripts obtained from fifty two Friday sermons. The Friday sermon transcripts were obtained through the official government website and then standardized by removing images and foreign letters; expanding acronyms and short forms; converting numbers and symbols to appropriate Malay words. The transcripts were then phonetically transcribed by first identifying the language rules and wrote a program based on those rules. The program was written using Personal Home Page (PHP) and the data were then stored into MySQL (Sequential Query Language). The data were then retrieved and compared to the Malay words used in news broadcast. In conclusion, the Malay used in Friday sermon and news broadcast differs in the usage of the phonemes /a/, /e/, /o/, /d/, /p/, /t∫/, /n/, /l/, /h/ and /r/.

Derivation of simple muscle fatigue index for biceps muscle based on surface electromyography temporal characteristics

Biceps brachii muscle which attached to the forearm bone is one of the important muscles to the athletes who involve in sports like badminton, tennis and volleyball. Repetition of the arm such as throwing and hitting can lead to muscle fatigue. This physiological phenomenon needs to be monitored and well controlled especially in athletes training. The purpose of this study was to formulate a simple muscle fatigue index for the biceps brachii muscles. Ten male badminton players were chosen to be the subjects for this study. Each subject was asked to do dynamic contraction by lifting 5 kilogram dumbbell. This exercise is called biceps curl exercise and the subjects were asked to repeat the task for one minute and thirty seconds. The electromyogram signal was recorded using Neuroprax EEG device. For that purpose, monopolar surface electrodes were attached to the biceps muscle of the subject. The electromyogram signals were then processed using MATLAB software. Four parameters in time domain were extracted; Zero Crossings (ZC), Root Mean Square (RMS), Mean Absolute Value (MAV), and Variance (VAR). Except for zero crossings (ZC), all other parameters showed significant difference between fatigue signal and non-fatigue signal (p-value <; 0.001). RMS was found to correlate very well with MAV (0.999). The study concludes that several temporal characteristics from electromyogram signal could be used in the formulation of biceps muscle fatigue index, supporting its use in monitoring muscle endurance.

Sound absorption coefficient of direct piercing carved wood panel with uniform geometric patterns

Direct piercing carved wood panels (DPCWP) have been used as part of the wall panel for mosques in this country. Among the earliest used of DPCWP is as in Masjid Sultan Zainal Abidin in 1700s, Kuala Terengganu, Terengganu. It is envisage, the use of DPCWP is to help in achieving good speech intelligibility inside. This is considering DPCWP allowing sound waves to pass through, hence sound reflection to the main prayer is contain. Minimizing sound reflection toward the mosque main area, ensuring optimization of speech intelligibility. DPCWP has the ability to allow sound waves to pass through the panel. This qualifies DPCWP as sound absorber material. This as Sabine, Kutruff and Maekawa definition of sound absorption coefficient. In this paper the sound absorption coefficient of DPCWP with uniform geometric patterns are discussed. The perforation ratios are 31% and 37%. Numerical experiments were conducted using Boundary Element Method (BEM). The measured results were obtained using sound intensity measurements technique. Comparison of sound absorption coefficient obtained through numerical experiment and measured using sound intensity are discussed in details. Analysis of resonance frequencies due to types and sizes of apertures in relation to sound absorption coefficient also highlighted. The measured and numerical results suggest, DPCWP of uniform geometric patterns indeed able to act as good sound absorber. This finding allows DPCWP to be used as sound absorber more effectively in future mosque construction.

Investigation of the effect of low frequency components of sound to speech intelligibility

Sound attenuation depends on source‐to‐listener distance, the finishes, and the shape of the room. The amount of sound attenuation at different frequencies influences the overall speech intelligibility in a room. The sound at high frequencies, especially at 1 kHz and 2 kHz, contribute the most for the articulation of consonants, and thus affects speech intelligibility. However, it has been found previously that sound attenuation is lower and harder to achieve at lower frequencies. This would lead us to assume that reverberant sound is mostly of low frequency components. Even if the contribution of sound at low frequency is low for speech intelligibility, this paper attempts to gauge the effect of sound pollution at low frequencies to the overall speech intelligibility in the room. With fixed source‐to‐listener distances, the measurements were conducted in classrooms with different sizes and finishes.

Speech intelligibility prediction of room with curved surfaces by means of its physical characteristics

In the room, it was found previously that the ear uses the first arriving sound to locate the source, but the early reflections contribute to the intelligibility. Late reflections, on the other hand reduce intelligibility. Therefore, for speech intelligibility a high sound energy fraction is necessary, requiring high early energy and low late energy. Spatial impression which is the subjective effect of early sound reflections that come from the side walls and ceiling, contributes to the sense of envelopment. This paper presents the investigation of speech intelligibility with respect to the physical characteristics of rooms with curved surfaces. The investigated physical characteristics are source‐to‐listener distance (Lr), listener‐to‐the farthest wall (Lwmax), listener‐to‐the closest wall (Lwmin), listener‐to‐the farthest wall and listener‐to‐the average distance to walls (Lwave). In addition to objective acoustics measures such as reverberation time (RT60), early decay time (EDT), average sound absorpt...

Investigation of early‐to‐late sound reflection effect in a room with a dome

The material of a dome is normally very sound reflective. This is due to the fact that the material for inner surfaces of the dome is made of hard material for endurance and easy maintenance. Also, the dome is often situated high above the floor of the room with the intention of providing larger volume and thus creating comfortable envelopment of the dome for people inside it. Due to the height from the floor and the hard material of its inner surfaces, the dome naturally manifests strong sound reflection, sound focusing effects and uneven sound pressure levels. These phenomena also give rise to the reverberation time in a room with a dome. It is the intention of this paper to discuss the effects of early‐to‐late sound reflection with respect to reverberation time and sound reverberant level in a room with a dome.

Investigation of speech intelligibility in building with curved surfaces by means of objective measures

There are two aspects in an acoustics design process that have to be taken care of in order for the room and the sound system to be intelligible. The first is the electronic part of the design. The second is the environment in which the system is to be installed. With the assumptions that the selection of sound system equipment and installation are correct and thorough, the sound reflection pattern and its delay in building with curved surfaces has to be investigated and understood. This paper investigates via measurements as well as through the simulation software the distribution of sound pressure level, sound delay (RT60), time and amplitude of early reflection (Rearly), and late reflection (Rlate) in a symmetrical room and in a room with curved surfaces. Rearly  is categorized as the first‐arriving wave‐front that happens before 35 ms and Rlate is that within 70 and 120 ms. Preliminary investigation has shown that the equal distribution of these objective measures is destroyed with the existence of cu...