An experiment featuring waterhammer in viscoelastic pipes is presented in which the effects of pipe-wall viscoelasticity on waterhammer pressures are investigated. A large-scale pipeline apparatus made of polyvinyl chloride (PVC) at Deltares, Delft, The Netherlands, has been used to carry out waterhammer experiments. Tests have been conducted in a reservoir-pipeline-valve system consisting of a...

This paper analyzes the effect of competition among downstream Žrms on an upstream Žrm’s payoff and on its incentive to integrate vertically when Žrms in both segments negotiate optimal contracts. We argue that as downstream competition becomes more intense, the upstream Žrm obtains a larger share of a smaller downstream industry proŽt. The upstream Žrm may encourage downstream competition (eve...

Abstract The present study investigated the risk associated with concentrations of lead and cadmium in tissues (gills, livers muscles) Blackchin tilapia ( Sarotherodon melanotheron ) from upstream downstream regions an intertidal creek Rivers State, Nigeria. trend Cd fish water was as follows: muscle > liver gills water. concentration higher when compared to fish. mean mg kg ?1 0.048 ± 0.015...

In recent years, a number of mergers have occurred in the petroleum industry involving upstream firms that are imperfectly integrated into retail markets. In order to empirically evaluate the competitive effects of such mergers, this paper proposes a structural model of supply and demand that reflects divisions between upstream producers and downstream retailers. Neither downstream costs includ...

This paper examines the relationship between a differentiated downstream market and a specialized upstream market. We analyze four different types of vertical relation between the upstream and downstream sectors when the upstream market supplies specialized and complementary inputs to a downstream product differentiated market. The first is the benchmark case of decentralized markets, the secon...

We examine whether cooperative planning and uncertainty affect the magnitude of rework in concurrent engineering projects with upstream and downstream operations, and explore the impact of such rework on project delays. Using survey data from a sample of 120 business process (BP) redesign and related information technology (IT) development projects in healthcare and telecommunications, our resu...

This paper examines the relationship between a differentiated downstream market and a specialized upstream market. We analyze four different ways price competition takes place between the upstream and downstream sectors when the upstream market supplies specialized and complementary inputs to a downstream product differentiated market. The first is the benchmark case of decentralized markets, t...

Open channel junction is one of the most common hydraulic structures that are used in various practical situations such as sewer, drainage, and flood control systems. Knowing the fluid flow behavior, is one of the most important topics in designing the efficient open channel junctions. The complexity and deviation of flow in the junction’s zone disrupts the proper functioning of the flowmeter d...