This study was conducted in Date Palm Technology Company Limited, Shambat, Khartoum State. To evaluate performance of three types of evaporative cooling pads for greenhouses (celdek pads, straw pads and sliced wood pads), as compared to the conditions outside the greenhouses (control), for pads. Performance evaluation includes environmental parameters (temperature and relative humidity at 8 am, 1 pm and 6 pm) and crop parameters (length and stem diameter, leaves number and width, fruit length and diameter, fruit weight and dry matter and yield). The results obtained for the temperature at 8 am showed that there was no significant difference (0.05) inside the greenhouses, while a high significant difference between the conditions inside and outside of the greenhouses was found. Significant differences were found at 1 pm and 6 pm between all treatments as compared to the conditions outside the greenhouses, and the results obtained for relative humidity showed high significant differences at 8 am and 1 pm inside the greenhouses and between inside and outside the greenhouse, respectively, while there was no significant difference at 6 pm inside the greenhouses and between inside and outside the greenhouses. On the other hand, the results obtained for crop parameters showed that there were significant differences between all parameters inside the greenhouses and outside the greenhouses; however, the greenhouses with sliced wood pads gave the highest yield and the greenhouses with straw pads gave the least and conditions outside gave the lowest. This study indicated that the sliced wood pads are better than the other evaporative cooling pads.

Fibre optic daylighting systems are a developing technology that offers solutions to daylighting designers. However, these systems are rarely used in the tropics because of the variable illumination provided by the sky, which changes with latitude, time of day, and seasons. This study examines the illumination levels obtained using a fibre optic daylighting system under various tropical climate conditions in Malaysia. A Parans SP3 fibre optic daylighting system with 10-m cable was used on a full-scale test bed model in Universiti Sains Malaysia as an empirical approach. The following results were obtained: (i) on sunny days with intermediate blue sky, the system worked at 79% and reached a maximum of 725 lx, an average of 457 lx, and a minimum of 98 lx; (ii) on moderately sunny days with intermediate mean sky, the system worked at 48.5% and reached a maximum 685 lx, an average of 439 lx, and a minimum of 80 lx; (iii) under overcast skies, the system worked at 37.5% and reached a maximum of 538 lx, an average of 305 lx, and a minimum of 41 lx. These findings provide benchmarking directions for the application of fibre optic daylighting systems in Malaysia.

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As a developing country, Malaysia requires innovation to keep abreast of the rapid growth of technology to meet the highly demanding energy consumption. The application of daylighting systems especially by fibre optics is very limited, due to the absence of relevant knowledge and the lack of understanding of the system requirements and potentials, particularly the technology of illuminating enclosed spaces which are totally surrounded by internal walls (opaque). Thus, the aim of this literature review is to shed light on this new approach and to help the building technologists activate its application in building interiors. This paper presents and summarises the important technical issues that enhance the adoption of this technique for the Malaysian built environment.

Ground-level ozone (O3) is mainly produced during daytime in the presence of ultraviolet (UV) light and later destroyed by nitrogen oxides during nighttime. However, light pollution caused by the excessive use of artificial lights may disrupt the chemistry of night-time ground-level O3 by providing enough energy to initiate nighttime ground-level O3 production. In this study, nighttime (7 p.m. to 7 a.m.) ground-level O3, nitrogen oxide (NO), and nitrogen dioxides (NO2) concentrations were observed for three years (2013, 2014, and 2015). The existence of O3 was found during nighttime, especially in urban areas with a concentration range of 8–20 ppb. The results suggested that nighttime variations of ground-level O3 concentrations were higher in urban areas than in suburban areas. The mean nighttime O3 concentration at urban sites varied, possibly because the distribution of anthropogenic lights around the urban sites is brighter than in suburban locations, as indicated by the data from the light-pollution map. This anthropogenic light has not caused the suspected nighttime photolysis processes, which directly slowed nighttime oxidation. The photochemistry rate of JNO2/k3 was supposed to be near zero because of the absence of photochemical reactions at night. However, the minimum concentration in all urban and suburban sites ranged from 2–3 ppb, indicating that O3 might also form at night, albeit not due to light pollution.

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