User talk:Pierre mertens

Crane Double Cycling in Container Ports:
As allways time is money, and therefore professionals are always searching for ways to improve ship dwell time in ports around the world. With container vessels the problem is probably even more clear than with other types of ships. As the crane returns empty every time it is sent back to the ship to pick up another container to be unloaded.

A possible solution to this problem could be what is called “Double Cycling”. To explain it briefly, the intention is that the crane will, everytime it unloaded a container will take on a new one to reduce moading/unloading time of the ship. However one can imagine that it won’t be easy to find a correct schedule to do this. Scheduling will prove to be mighty difficult.

A solution to this problem was formulated by Anne V. Goodchild and Carlos F. Daganzo in their paper calles “Crane Double Cycling in Container Ports: Affect on Ship Dwell Time” (April 1, 2005). They provide two solution algorithms and simple formulae to estimate reductions in the number of operations, and operating time. Small problems can be solved to optimality with a standard numerical solver, but problems of typical size are computationally burdensome and terminated after 10 hours with optimality gaps larger than 50%. A formula for an improved lower bound to the optimal solution is developed and shows the optimality gaps are actually below 2.5% in all cases. The paper presents a greedy algorithm that can obtain solutions in seconds. A formula for an upper bound to the greedy algorithm's performance can be used to accurately predict crane performance. The problem is extended to include an analysis of double-cycling when ships have deck hatches. Results are presented for many simulated vessels, and compared to empirical data from a real-world trial. The paper demonstrates that analytical methods can be used in addition to numerical methods to provide greater insight. More importantly, the paper demonstrates that double-cycling can create significant efficiency gains.

Proposed deletion of Crane Double Cycling in Container Ports


The article Crane Double Cycling in Container Ports has been proposed for deletion&#32; because of the following concern:
 * Potential WP:OR. No references. No indication of notability. Merge to Container crane doesn't look like a good idea. Unable to deorphan.

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on |the article's talk page.

Please consider improving the article to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. ~Kvng (talk) 16:42, 11 August 2015 (UTC)