Flowshop scheduling with limited temporary storage

Bibliography: leaves 42-43.NSF Grant MCS77-01192 and NSF/RANN Grant APR76-12036.by Christos H. Papadimitriou, Paris C. Kanellakis

Performance Models for Data Transfers: A Case Study with Molecular Chemistry Kernels

With increasing complexity of hardwares, systems with different memory nodes are ubiquitous in High Performance Computing (HPC). It is paramount to develop strategies to overlap the data transfers between memory nodes with computations in order to exploit the full potential of these systems. In this article, we consider the problem of deciding the order of data transfers between two memory nodes for a set of independent tasks with the objective to minimize the makespan. We prove that with limited memory capacity, obtaining the optimal order of data transfers is a NP-complete problem. We propose several heuristics for this problem and provide details about their favorable situations. We present an analysis of our heuristics on traces, obtained by running 2 molecular chemistry kernels, namely, Hartree-Fock (HF) and Coupled Cluster Single Double (CCSD) on 10 nodes of an HPC system. Our results show that some of our heuristics achieve significant overlap for moderate memory capacities and are very close to the lower bound of makespan

A Review on Quantitative Approaches for Dock Door Assignment in Cross-Docking

Cross docking is a relatively new technique in supply chain operations. It offers limited storage time to maximize the efficiency of goods transshipment. Efficient operation of a cross docking system requires an appropriate coordination of inbound and outbound flows, accurate planning and dynamic scheduling.  The planning strategies at cross docking terminals, which are receiving growing attention today, are the truck-to-door assignment and destination to door assignment problems. This paper provides a comprehensive literature review of quantitative approaches in dock door assignment problems of cross docking planning. The contributions of this paper are to identify the gap of knowledge in operational levels mainly in dock door assignment and to point out the future research direction in cross docking

Minimizing makespan in flowshops with pallet requirements: computational complexity

Studies the minimization in flowshops with pallet requirements. Importance of pallets in automated or flexible manufacturing environments; Mounting and dismounting of work pieces; Planning problems involved

Alternatívy k MILP pre rozvrhovanie dávkových banských procesov

Cie¾om príspevku je navrhnú monos, nahradenia optimalizaèných metód na báze zmieaného celoèíselného programovania pouitím pribliných metód rozhodovania (heuristika) v oblasti plánovania a riadenia banských procesov. Výsledkom tohto poèítaèom podporaovaného plánovania sú detailné výrobné rozvrhy vytvorené pod¾a poiadaviek ako sú vysoká efektivita výroby, alebo zníená redukcia odpadov. Tieto problémy patria medzi zloité, NP-úplné problémy, èie ich rieenie je v súèasnosti pod¾a náho názoru pre reálne problémy efektívnejie s pomocou heuristík. Heuristiky uvedené v príspevku sú: simulované íhanie, tabu search a genetické algoritmy. Tabu search(metóda zakázaného preh¾adávania), aj keï sa jedná o heuristiku, je v tandardnej verzii deterministicky stachastická. V prispevku sú zhrnuté hlavné výhody heuristík v porovnaní s MILP, predovetkým ich rýchlos a jednoduchos a teda aj niie nároky na výpoètovú techniku a software, ako aj kvalita poskytovaných výsledkov. Èlánok uvádza struèný popis rieených problémov a základy matematického popisu týchto problémov, zhrnuté sú aj rôzne ciele optimalizácie reprezentované rôznymi cie¾ovými kritériami. Príspevok ïalej popisuje jednotlivé heuristiky, ich princípy, ich vlastnosti a ich monosti, poiadavky ktoré musí úloha splòova, aby bolo moné algoritmus poui. Prekadú z uvedených heuristík uvádzame aj slovný popis jednotlivých èastí algoritmu. Èlánok uvádza jednotlivé výsledky porovnania výkonov týchto heuristík oproti MILP, uvedené sú aj výsledky aplikácie týchto algoritmov na iné podobné problémy v chemickom priemysle. Vzh¾adom k zámerom tohto príspevku text obsahuje aj odkazy na ïaliu literatúru zaoberajúcu sa touto problematikou

Scheduling Multiproduct Chemical Batch Processes using Matrix Representation

Batch process plants are usually designed for the production of specialty and fine chemicals such as paint, food and pharmaceutical to meet specific product requirements as set by current market demand. Batch process plants can be operated as single product in which only one product is produced and multiple products which allow production of more than one product using same batch facility. The economics of the batch process heavily depends on efficient scheduling of the different tasks involved in manufacturing the range of products. The main objective of scheduling is generally to minimize completion time known as the makespan of the batch process. Product sequencing, which is used to set order of products to be produced, has a direct impact on the makespan particularly in the multiple products case. Another effect on makespan is observed for different transfer policies used to transfer the product intermediates between process stages. The generally adopted intermediate transfer policies are (i) zero wait (ZW), (ii) no intermediate storage (NIS), (iii) unlimited intermediate storage (UIS) and (iv) finite intermediate storage (FIS). In the past, the determination of makespan for each transfer policy has been done using a number of mathematical and heuristics approaches. Although these approaches are very efficient and are currently being applied in many chemical process industries but most of them end up with the solution in terms of complex mathematical models that usually lack user interactions for having insights of the scheduling procedure. This motivated the current work to develop relatively simple and interactive alternate approaches to determine makespan. The proposed approach uses matrix to represent the batch process recipe. The matrix is then solved to determine the makespan of a selected production sequence. Rearrangement of the matrix rows according to the varied production sequences possible for the specified batch process recipes enables the makespan to be determined for each sequence. Designer is then provided with the production sequence options with its corresponding makespan from which a selection could be made according to the process requirements

Complex materials handling and assembly systems.

Report covers June 1, 1976-July 31, 1978.Each v. has also a distinctive title.National Science Foundation. Grant NSF/RANN APR76-12036 National Science Foundation. Grant DAR78-1782

Secuenciación con Almacenes Limitados. Una Revisión de la Literatura

[ES] Tradicionalmente, en la aproximación formal a la secuenciación de producción denominada en inglés Theory of Scheduling (o simplemente scheduling), se suele obviar la limitación de capacidad entre los diferentes recursos de cara a establecer el programa de producción. Sin embargo, el paradigma Lean Manufacturing ha dejado patente que la limitación de capacidad física en los sistemas productivos es una característica que influye en los resultados de los programas de producción, por lo que las configuraciones empezando a ser objeto de estudio en la dirección de operaciones. En este artículo se hace una revisión de las principales características de la secuenciación con almacenes limitados que se han abordado bajo la teoría de secuenciación y se resumen las referencias más importantes publicadas durante los últimos años. Finalmente, se presentan una serie de conclusiones con el objetivo de clarificar algunas líneas de interés para los investigadores del tema.Andrés Romano, C.; Maheut, J. (2018). Secuenciación con Almacenes Limitados. Una Revisión de la Literatura. Dirección y organización (Online). 66:17-33. http://hdl.handle.net/10251/145863S17336