Mega shopping mall projects have seen dramatic growth and great development in recent years in Egypt. Many new mega shopping mall projects are under construction and expecting to start working in the few coming years....Mega shopping mall projects have seen dramatic growth and great development in recent years in Egypt. Many new mega shopping mall projects are under construction and expecting to start working in the few coming years. In the absence of researches studying the Egyptian mega shopping mall projects, this study tries to highlight the most critical risks that face these projects and the associated most effective response methods to be employed. The scope covers the analysis from different perspectives by including owners/developers, designers, consultants, project managers, and contractors that have previous experience in large-scale projects such as shopping mall projects. In this study, 30 construction project risks are classified into six main categories according to their type and 150 risk mitigation/elimination measures are introduced to overcome the impact of risks under each of these risk categories. The results reveal that the main risk category that faces the mega shopping mall projects in Egypt is the one including the financial risk factors. The most critical risk factor that faces these projects is the financial ability of the client. These results are similar to findings by previous researches conducted for large projects in other countries.展开更多
The accurate measurement method of ultrasonic velocity by the pulse interference method with eliminating the diffraction effect has been investigated in VHF range experimentally. Two silicate glasses were taken as the...The accurate measurement method of ultrasonic velocity by the pulse interference method with eliminating the diffraction effect has been investigated in VHF range experimentally. Two silicate glasses were taken as the specimens, their frequency dependences of longitudinal velocities were measured in the frequency range 50-350 MHz, and the phase advances of ultrasonic signals caused by diffraction effect were calculated using A. O. Williams' theoretical expression. For the frequency dependences of longitudinal velocities, the measurement results were in good agreement with the simulation ones in which the phase advances were included. It has been shown that the velocity error due to diffraction effect can be corrected very well by this method.展开更多
文摘Mega shopping mall projects have seen dramatic growth and great development in recent years in Egypt. Many new mega shopping mall projects are under construction and expecting to start working in the few coming years. In the absence of researches studying the Egyptian mega shopping mall projects, this study tries to highlight the most critical risks that face these projects and the associated most effective response methods to be employed. The scope covers the analysis from different perspectives by including owners/developers, designers, consultants, project managers, and contractors that have previous experience in large-scale projects such as shopping mall projects. In this study, 30 construction project risks are classified into six main categories according to their type and 150 risk mitigation/elimination measures are introduced to overcome the impact of risks under each of these risk categories. The results reveal that the main risk category that faces the mega shopping mall projects in Egypt is the one including the financial risk factors. The most critical risk factor that faces these projects is the financial ability of the client. These results are similar to findings by previous researches conducted for large projects in other countries.
文摘The accurate measurement method of ultrasonic velocity by the pulse interference method with eliminating the diffraction effect has been investigated in VHF range experimentally. Two silicate glasses were taken as the specimens, their frequency dependences of longitudinal velocities were measured in the frequency range 50-350 MHz, and the phase advances of ultrasonic signals caused by diffraction effect were calculated using A. O. Williams' theoretical expression. For the frequency dependences of longitudinal velocities, the measurement results were in good agreement with the simulation ones in which the phase advances were included. It has been shown that the velocity error due to diffraction effect can be corrected very well by this method.