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The conversion of the concept and the teaching of approximation function for analog low pass filter to computer aided numerical class project as an active learning strategy is presented. Governing equations for five approximation functions are presented and discussed. It is recommended that students are tasked to develop computer programs in any convenient computer programming language to make the pole-zero plot, obtain the transfer function, and plot the frequency response of low pass filters. Steps for such programs are suggested. Typical programs were developed and tested. The pole-zero plots and frequency response graphs generated are good illustrative and innovative teaching aids. Linear-phase response over the passband is a characteristic of Bessel approximation function but suffers less amplitude discrimination in the stopband. Chebyshev and Inverse Chebyshev approximation functions have the same order requirement which is usually greater than that of Elliptic approximation function but less than that of Butterworth approximation function. Elliptic approximation function is the best choice although it is more complex than the others. Through this computer aided numerical class project, the authors themselves gained more insight in the subject matter; certainly, students will learn actively.

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Monaural source separation is an interesting area that has received much attention in the signal processing community as it is a pre-processing step in many applications. However, many solutions have been developed to achieve clean separation based on Non-Negative Matrix Factorization (NMF). In this work, we proposed a variant of Itakura-Saito Divergence NMF based on source filter model that captures the temporal continuity of speech signal. The algorithm shows a very good separation results for mixture of two speech sources in terms of artifacts reduction. Besides that, Source to distortion ratio (SDR) and Source to Artifact Ratio (SAR) were found to be higher when compared with NMF algorithms with Kullback-Leibler and Euclidean divergences.

Surgical site infections (SSIs) in developing countries have been linked to inadequate availability of sterilising equipment. Existing autoclaves are mostly unaffordable by rural healthcare practitioners, and when they managed to procure them, the electricity supply to power the autoclaves is epileptic. The solar-powered autoclave alternatives are too bulky with a very high initial cost. Hence, low-cost biofuel-powered autoclave becomes an attractive option, and this study sought to present the design, development and clinical evaluation of the device performance. With the global drive for the adoption of green energy, biofuel will not only reduce greenhouse gas emission but also provide revenue for local producers and reduce biomass associated health complications. The theoretical energy requirement for the sterilisation process was calculated. The standard pressure and temperature needed for sterilisation were tested to be 121 C and 15 psi. The device was also clinically tested with Staphylococcus aureus bacteria obtained from the

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Good quality restful sleep is indispensable to mental and physical health. However, pressure due to busy life style, work and sometimes physiological factors have placed constraints on adequate and healthy sleep pattern leading to several sleep disorders such as insomnia, sleep apnea and restless leg syndrome. Sleep disorder affects the quality of life of such patients as it grossly reduces efficiency at work and leads to poor mental and physical health. Available drugs to treat this disorder are addictive with strong adverse effects, while existing devices to provide intervention are very expensive. Hence, the development of an affordable, portable electronic sleep inducer with display unit is presented. It uses geomagnetic property of the earth coupled with electromagnetic wave induction to stimulate sleep. The signal frequency was generated by IC4047 coupled with Arduino Uno and ATmega 328p for device control. The output of this electronic sleep inducer is found to satisfactorily produce 5.89 Hz and 3.58 Hz for theta and delta waves respectively, needed to induce sleep. It consumes less power and it is rechargeable. Keywords— Sleep; Sleep disorder; Insomnia; Geomagnetic wave;