Determination of Melting Layer Boundaries and Attenuation Evaluation in Equatorial Malaysia at Ku-Band

Upsurge in bandwidth demand in recent times for real-time data transmission have put serious constraints on satellite communication channels, leading to congestion of the lower frequency bands; necessitating migration to higher bands (Ku, Ka and V) with attendant problems such as signal fading, depolarization and attenuation due to presence of hydrometeors. There is need to separately account for attenuation due to the melting layer along the earth-space microwave links. One year data from ground-based S-band meteorological radar sourced from Kluang station of the Malaysian Meteorological Department was processed to build the vertical reflectivity of rain profile for UTM, Malaysia. Results from this work suggested that the effects of the melting layer on signal attenuation at Ku-band can be quite significant in the tropical and equatorial regions. It was estimated to be 13.36 dB and 15.44 dB at 0.01% of the time exceeded using Laws-parsons and Marshall-Palmer regression coefficients, respectively. Furthermore, it was observed that ITU-R. P.618-11 model largely under-estimated the attenuation along the slant-paths because of its failure to account for attenuation due to the melting layer in its formulation by its assumption of constant rain rate; thus rendering it unsuitable for rain attenuation predictions in the tropics

The Design and Development of A Tajweed Learning Innovation

E-Tajweed Yadun is a mobile application developed for learning the science of tajweed effortlessly and efficiently. The application can be simply downloaded and accessed anytime, anywhere. It involves a combination of multimedia and creative graphic elements of a ‘Yadun' model which is an Arabic term for ‘hand'. e-Tajweed Yadun aims to create an interactive self-learning environment for deeper understanding and memorization of specific tajweed laws that could be burdensome when learned via books and conventional drills. The development of e-Tajweed Yadun involved five phases, namely theoretical study and needs analysis, model development, prototype design, prototype development and evaluation. e-Tajweed Yadun is a new alternative technique to learn the science of tajweed, particularly for Muslim students, as a guide while reading the Qur'an. Keywords: e-Tajweed, Yadun, application, innovatio

Theoretical and experimental simulation of roof-top bus multiple-circuit air-conditioning system performance

Many air-conditioning (AC) systems are designed to operate at maximum cooling capacity regardless of the variation in the daily cooling load. At low loads, the conditions can be uncomfortably cold and the overcooling is an unnecessary waste of energy. To address these two issues, a multiple refrigeration circuit concept is proposed and applied to a roof-top bus AC system. A two-circuit model is proposed for a standard bus size in which each circuit has two evaporators of equal sizes arranged in parallel and installed on each passenger row, respectively. This means that each passenger row is served by two different evaporators sharing a common heat exchanger box. Depending on the cooling load, this concept allows one or both circuits (compressor motors) to be switched on and during either modes, it also allows one or more sets of evaporator blowers to be switched on. A steady-state computer model has been developed to simulate the performance of the proposed two-circuit AC system. A two-circuit air conditioner is also designed to form a roof-top bus AC system, fabricated, and installed on to an experimental rig. The experimental data are used to validate the computer model. The validation is on the system thermal performance and on the evaporator air outlet conditions (dry bulb temperature and relative humidity) at different modes of system operation, either at full or partial cooling loads. The simulated results gave satisfactory agreement with those obtained from the experimental work. Maximum absolute deviations are within the range of 19.3 per cent, although most of the simulated results are less than a 10 per cent range from the experimental ones, which validates the computer program. The paper describes the modelling work carried out and the results obtained are presented in comparison with the experimental data

A comprehensive review of barriers to a functional Zakat system in Nigeria: what needs to be done?

Purpose: Muslims in Nigeria, like in many Muslim-majority countries, are striving to have a functional Zakat system in search of solutions to the perennial problem of poverty and its damning consequences. Nevertheless, there are still unsettled concerns arising from the current and widespread implementation of dissimilar (diverse) approaches to the Zakat system in various parts of the country. The purpose of this paper is to review comprehensively what are the hindrances of a vibrant Zakat system and how far the identified impediments may affect the system in the Nigerian context.Design/methodology/approach:The methodology adopted is the review of extant relevant literature in the field of scholarly publications.Findings: The findings of this study revealed that the fragmented implementation of the Zakat system within the context of the Nigerian democratic system of government lead to the weak governance with respect to law, administration and management; lack of a generally accepted fatwa from the Muslims scholars (Ulamas); absence of Zakat accounting standard; and low compliance behavior are the major barriers that require the attention of government and other stakeholders such as the traditional leaders, the accounting regulatory bodies, the Ulamas, as well as the economic and accounting researchers.Practical implications: It was recommended that the stakeholders should make concerted efforts toward ensuring success of the Zakat system for attaining salvation in the hereafter and for social security, as well as economic prosperity. Originality/value: The paper is the first paper that comprehensively reviews previous literature in the Zakat environment on factors that become barriers to implement a comprehensive Zakat system in Nigeria