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Development in the textile industry leads to an increased demand for the use of various dyes. Moreover, there is the use of some dyes in the food industry as well as medical diagnostics. Thereby, increased demand for dyes in various fields has resulted in dye-containing wastewater. Only a small portion of the generated wastewater is adequately treated. The rest is usually dumped or otherwise directly discharged into the sewage system, which ultimately enters rivers, lakes, and streams. The handling and disposal of such concentrated wastewater, especially the dye-containing wastewater, is considered to be a major environmental issue from the moment of its generation to its ultimate disposal. Conventional water treatment methods such as flotation, filtration, adsorption, etc., are non-destructive physical separation processes. They only transfer the pollutants to other phases, thereby generating concentrated deposits. The advanced oxidation process (AOP) is one of the most effective emerging methods for the treatment of wastewater containing chemical pollutants. The method involves the formation and interaction of highly reactive hydroxyl radicals under suitable activation conditions. These radicals are non-selective and efficient for the destruction and eventual mineralization of recalcitrant organic pollutants. This review aims at the pros and cons of using photocatalysis as an efficient AOP to degrade dye-containing wastewater.

Spare parts inventory management is very important to ensure smooth operation of maintenance department. The main objectives of inventory management of spare parts are to ensure the availability of spares and materials for the maintenance tasks and increase the productivity of the maintenance department. This research centred on the development of the Computerised Inventory Management System (CIMS) for the maintenance team at Weida Integrated Industries Sdn. Bhd. The inventory management technique used to control the spare parts inventory in this research was the basic Economic Order Quantity models (EOQ). However, the CIMS developed is unique as it has the ability in handling inventories in multiple-storage locations. The CIMS was written using the Visual Basic 2010 software. This CIMS has the abilities to keep records and process the spare parts information effectively and faster besides helping the user to perform spare parts ordering tasks compared to the current manual recording. In addition, the ordering quantity and frequency for the CIMS is determined through the EOQ technique. However, observation indicates that the overall average inventory level currently at the factory is lower than the expected overall average inventory level produced by the CIMS. This is due to the fact that the CIMS was unable to consider the opening stock in ordering the inventories. Therefore, further improvements are needed to optimize the performance of the system such as using the EOQ with the reorder point technique, the periodic or continuous review system.

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An air-conditioning and mechanical ventilation (ACMV) construction project involved many interrelated construction activities with varying durations and multiple dependencies. This paper focuses on the development of a best possible project planning and scheduling technique that can help the project manager to manage and complete the ACMV project in optimal time. The program evaluation and review technique (PERT) is used in this research. The PERT technique helps to determine the probabilities of various stages of the project by specified deadlines and identify the activities on the critical path that have high potential for causing delays in the project completion time. The completion times of 72, 76, 79, and 80 weeks were taken for the PERT analysis. Deadline of 72 weeks is the contractual period of the ACMV project as specified in the contract. Completion time of 76 weeks is the critical path of the project as analyzed by the PERT technique. The deadline of 79 weeks is the proposed completion time for the ACMV project whereas 80 weeks are the actual completion date of the project. The PERT analysis revealed that the project completion time of 72 weeks, which is as stated in the contractual completion time, yielded the probability of completion of 2.67% only. This analysis shows that the contractual period is impossible to be achieved and it is an unrealistic time setting. Further negotiation is required including changing or extending of the contractual completion time. The other completion times are able to be achieved but the company may need to face the high penalty costs due to the delays in completion time.