Browsing by Author "Bader, Mahmoud Fathi"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    The Effects of Different Faucet Aerators on Bacterial Growth and Water Quality
    (The British University in Dubai (BUiD), 2011-04) Bader, Mahmoud Fathi
    Sustainable innovations aimed at protecting future generations from the effects of the global warming in addition to preserving precious natural resources such as water. Water conservation is one of the green building features, which may be achieved by using appropriate water saving plumbing fixtures like faucet aerators. Although benefit may be achieved by using such fixtures, there are also negative side effects to their use. This study was conducted in Dubai International Academic City (DIAC), to investigate the consequences of using different faucet aerators on bacterial re-growth which may compromise the quality of the water; and to check the deterioration of the efficiency of the aerators over the time. The study is based on experimental method. Four types of faucet aerators were used, and monitored every four weeks over a six month period. 120 water samples were collected from 16 faucet aerators, and there were also 3 control points which were under three different water pressures. The water tank was also tested. A Heterotrophic Plate count was used since it is a common indicator for the monitoring of microbiological water quality in distribution systems. The samples were tested in Dubai Municipality Central Laboratory. The water flow rates, pH and temperatures were measured in the field. The results revealed that, from cycle one to cycle four, the HPC bacteria concentration in the water tank exceeded the threshold level of 500 cfu/ml. Although the HPC concentration in the water tank dropped to a 4 level below 500 cfu/ml due to treatment from the main source, the HPC concentrations in the faucet aerators remained high. The study concluded that, water pressure less than 2.5 water bar has potential to enhance the growth of bacteria in the aerators. Furthermore, the aerators saved 20% to 80% of the water and that depended on the aerator types as well as the water pressure. Finally the research recommends that, a three month periodic maintenance for the aerators might avoid the accumulation of sediments, which were the main contributor to bacterial growth.
  • Thumbnail Image
    Item
    Impact of ‘back to back’ payment clause on the cash flow of subcontractor in the UAE
    (The British University in Dubai (BUiD), 2013-05) Bader, Mahmoud Fathi
    Any default by the employer, by not paying on time or nonpaying at all, will adversely affect the parties down in the supply chain in construction project. The contractor tries to cope with such problem by limiting his liability via terms in the contract, such as back-to-back payment terms, with his subcontractors and suppliers. Back to back payment clause has different meanings and forms and its interpretation may vary among the different legal systems. Common law is inclined to invalidate such clause. The situation under the UAE law is different as there is no explicit term in the current law that invalidates the back to back payment clause. The research aimed at investigating the impact of ‘back-to-back’ payment terms on the cash flows of subcontractors and main contractor’s and try to find solutions for securing the subcontractor payments. A total of 96 questionnaire responses were collected from different construction professionals involved in the contract administration or drafting in the UAE. The research asserted that most of the professional participated in the survey felt uncomfortable with back to back payment term. Furthermore, most of the subcontractor participated in the survey have encountered problems due to back to back payment clause Back to back clause has significant impacts in the cash flows of the main contractors and subcontractors. As 65% of the entire professionals participated in the survey claimed so. Furthermore, according to most of the respondents to the survey, back to back clause in unfair term and should be invalidated by the law To conclude, it is worthwhile to the parties to be clear in their contract terms with regards to payment certification and mechanisms. In addition, the legislator should be inspired by the other common laws to adopt payment mechanisms and certainty in the construction industry.