Salah Saleh

• Doctor of Philosophy
• University of Tripoli

Design optimization procedures for water distribution systems generally assume that the nodal demands follow the same diurnal pattern, which implies that the demands are fully synchronised and perfectly correlated. However, it is well known that in practice the spatial correlation of the demands is not perfect; i.e. the cross-correlation is less th...

The flow entropy, when increased, has been revealed to: produce designs with improvements in the hydraulic reliability; make use of the arrangements of the flow paths in layout optimization; produce high uniformity of the pipe diameters in line with increase in the reliability; provide strong positive correlation with hydraulic reliability and fail...

An investigation into the effectiveness of surrogate measures for the hydraulic reliability and/or redundancy of water distribution systems is presented. The measures considered are statistical flow entropy, resilience index, network resilience and surplus power factor. Looped network designs that are maximally noncommittal to the surrogate reliabi...

A new multi-directional search approach that aims at maximizing the flow entropy of water distribution systems is investigated. The aim is to develop an efficient and practical maximum entropy based approach. The resulting optimization problem has four objectives, and the merits of objective reduction in the computational solution of the problem ar...

There is a growing body of evidence that, on average, hydraulic reliability of water distribution systems increases in line with entropy of the pipe flows. Motivated by the existence of large sets of flow directions in looped water distribution systems along with the computational simplicity of the informational entropy function, a multi-directiona...

A new multi-objective evolutionary optimization approach for joint topology and pipe size design of water distribution systems is presented. The algorithm proposed considers simultaneously the adequacy of flow and pressure at the demand nodes; the initial construction cost; the network topology; and a measure of hydraulic capacity reliability. The...

This paper describes a new multi-objective evolutionary optimization approach to the simultaneous layout and pipe size design of water distribution systems. Pressure-deficient and topologically infeasible solutions are fully incorporated in the genetic algorithm without recourse to constraint violation penalties or tournaments. The proposed approac...

An unbiased investigation is presented of four surrogate reliability measures which are commonly used in the water distribution system (WDS) literature. Each measure substantially reduces the computational effort required to assess the hydraulic reliability of a WDS, in comparison with the highly accurate measures which are available. A series of r...

Many studies have attempted to design Water Distribution Systems (WDS) to deliver maximum entropy flows for the purpose of achieving reliable designs. Recently, the Global Maximum Entropy Minimum Cost (GMEMC) design approach was proposed. However, no investigations on the mathematical ability of the approach in achieving the GMEMC design have been...

The problem of designing water distribution systems to deliver the Global Maximum Entropy (GME) flows was hitherto hampered by the multiplicity of feasible flow directions associated with looped water distribution networks. This paper addresses this issue by presenting a new multi-objective approach to the design optimization of water distribution...

There is ever increasing commercial and regulatory pressure to minimise the cost of water distribution networks even as the demand for them keeps on growing. But cost minimizing is only one of the demands placed on the network design. Satisfactory networks are required to operate above a minimum level even if they experience failure of components....