A perpendicular array PA,(t, k, u) is a n(y) by k array A of u distinct symbols, which satisfies: (i) every row of A contains k distinct symbols, (ii) for any t columns, and for any t distinct symbols, there are precisely 2 rows with the given symbols in the given columns. Such a structure may also be described as a A-uniform, t-homogeneous set of injective mappings from a k-set into a u-set. A...

We study the problem of designing layout facilities for the navigation of an “infinite” graph, i.e. a graph that is so large that its visualization is unfeasible, even by gluing together all the screen snapshots that a user can take during the navigation. We propose a framework for designing layout facilities that support the navigation of an infinite tree. The framework allows to exploit the k...

Pott, A. and M. Shriklande, t-Designs with few intersection numbers, Discrete Mathematics 90 (1991) 215-217. We give a method to obtain new i-designs from t-designs with j distinct intersection numbers if i + j 1 does not exceed t.

A facility layout problem is concerned with determining the best position of departments, cells, or machines on the plant. An efficient layout contributes to the overall efficiency of operations. It’s been proved that, when system characteristics change, it can cause a significant increase in material handling cost. Consequently, the efficiency of the current layout decreases or is lost and it ...

Quality of a layout has the most direct impact in the manufacturability of a design. Traditionally, layout quality is ensured in the first order by design rules, i.e. if a layout is free of design rules violation, it is a good layout. It is assumed such a layout will be fabricated to specification. Moreover, a design rule clean layout also ensures the electrical performance of the circuit it re...

This paper presents a formulation of the facilities block layout problem which explicitly considers uncertainty in material handling costs on a continuous scale by use of expected values and standard deviations of product forecasts. This formulation is solved using a genetic algorithm meta-heuristic with a flexible bay construct of the departments and total facility area. It is shown that depen...

Thin film flows naturally arise in a wide variety of industrial and environmental problems ranging from microchip manufacturing, structured packing to lava flows in geology. In particular, wind-driven flows of liquid films are of great interests for deeper understanding of aircraft icing and better design of anti-icing and de-icing strategies. Currently, most thickness mapping techniques involv...

This paper tackles the design of fairs which are subject to layout considerations. A fair means a large scale exhibition for goods and services like a trade fair or a regional fair. A method for designing fair layouts using a slicing structure and the horseshoe cut is presented, and numerical results for the layout of a real fair are reported. The selected criterias are evaluated using the obta...

This paper develops a new mathematical model that integrates layout design and production planning to prescribe efficient multi-bay manufacturing facilities. The model addresses the need to distribute department replicas throughout the facility and extends the use of product and process requirements as problem parameters in order to increase process routing flexibility. In addition, the model a...

The use of the simulation-based technique in facility layout has been a choice in the industry due to its convenience and efficient generation of results. Nevertheless, the solutions generated are not capable of addressing delays due to worker’s health and safety which significantly impact overall operational efficiency. It is, therefore, critical to incorporate ergonomics in facility design. I...