2,209 research outputs found

    Experiment study on overtopping of sloping breakwater by swell

    Get PDF
    Along with global climate changing, the disaster caused by overtopping from breakwater or revetment seems further serious. There are many factors which related with wave overtopping flux, one is wave period, some researches have big gap on it. Three formulas of overtopping flux were compared on wave period influence. Eight\ud sections of single sloping breakwater without super structure were tested in wave flume. The overtopping was measured under different wave periods. The measured values were compared with calculation results. Wave run-up was calculated to analyze the difference of overtopping between measurement and calculation, and it showed that the cases which had much difference were splashing. The factor L/H was adopted to improve the existed formula as multiple

    On the equivalence of strong formulations for capacitated multi-level lot sizing problems with setup times

    Get PDF
    Several mixed integer programming formulations have been proposed for modeling capacitated multi-level lot sizing problems with setup times. These formulations include the so-called facility location formulation, the shortest route formulation, and the inventory and lot sizing formulation with (l,S) inequalities. In this paper, we demonstrate the equivalence of these formulations when the integrality requirement is relaxed for any subset of binary setup decision variables. This equivalence has significant implications for decomposition-based methods since same optimal solution values are obtained no matter which formulation is used. In particular, we discuss the relax-and-fix method, a decomposition-based heuristic used for the efficient solution of hard lot sizing problems. Computational tests allow us to compare the effectiveness of different formulations using benchmark problems. The choice of formulation directly affects the required computational effort, and our results therefore provide guidelines on choosing an effective formulation during the development of heuristic-based solution procedures
    • …
    corecore