Nelio Domingues Pizzolato

Localização de escolas públicas: síntese de algumas linhas de experiências no Brasil

This paper reports a methodology for locating public elementary schools in urban settings. The proposed methodology is divided in two complementary parts: the evaluation of the current location and a relocation proposal. In addition to the methodological review the paper outlines five studies made in Brazilian cities or large areas, which are: Nova Iguacu, Nilopolis, Niteroi, Ilha do Governador and Fortaleza. The study emphasizes the methodological evolution from paper maps up to geocoded maps using softwares of the GIS family (Geographic Information System) such as ArcView and GeoRedes. The study also evaluates the managerial importance of each one of the five studies.

Localização de escolas do ensino fundamental com modelos capacitado e não-capacitado: caso de Vitória/ES

The present study is divided in three parts. In the first part, the objective of the study is to evaluate the current location of public schools. The spatial distribution is evaluated with the p-median model and the Arcview, a GIS software. Given the existing capacity, regions with excess or shortage of school places have been identified. In the second part, a heuristic algorithm to solve the p-median problem has been used and the proposed locations identified. This study proposes an ideal distribution of the school network which takes into consideration the recent demographic modifications experienced in the area. The third part of the study assumes that schools have a single standard size and considers the capacitated p-median using an special purpose algorithm. The study was applied to the location of elementary public schools in the city of Vitoria, a state capital with about 300,000 inhabitants located in the southeast part of Brazil. The number of school children is 45,766 with 51 public schools, according to the 2000 National Census.

LOCATING PUBLIC SCHOOLS IN FAST EXPANDING AREAS: APPLICATION OF THE CAPACITATED p-MEDIAN AND MAXIMAL COVERING LOCATION MODELS

The area of Guaratiba, in Rio de Janeiro, presents extraordinary population growth rates that exceed all other districts of the city. Moreover, the public investments underway, in view of the 2106 Olympic Games, are making the region even more attractive. Therefore, it is appropriate to suggest proactive measures to avoid the predicted collapse of several public systems among them the education system. This paper considers the projected population for the years 2015 and 2020 and, using various computing resources, specially the ArcGIS Network Analyst tool for measuring traveled distances, proposes locating new facilities with the Capacitated p-Median Model and with the Maximum Covering Location Problem, considering an ideal maximal home-school distance of 1,500 meters, but also evaluating longer distances. Both problems have been solved with AIMMS. The consideration of both models provides a constructive insight that certainly improves the implemented solution and favors the local community.

The Vehicle Routeing Problem

Reports on a study of a vehicle routeing problem as a pilot project. Outlines the motivation to embark on such an experimental study, the data collection process, the software, and the problems detected. Summarizes the gains derived from the research and explains resistance.

A two‐stage hub location method for air transportation in Brazil

During the past decade, the Brazilian air passenger market has been growing at impressive rates suggesting the need for rationalization and the consistent use of the hub-and-spoke configuration. This research considers 135 airports, mostly extremely small, and the aim is to identify regional hubs that would accumulate traffic and feed a predefined restricted number of major hubs. The proposed approach is divided into two phases: the first phase considers all 135 existing commercial airports and using the p-median problem identifies p airports that would play the role of regional hubs, and the second phase considers a problem with these p airports and solves the q-hub location problem. Both phases are sequentially solved by the software AIMMS 3.9. The research has broad implications consistent with the publicized efforts to improve management practices, support a larger number of commercial airports, and face the expected peak demand in the upcoming international events. Given the growth in the air passenger market in Brazil, both phases may be seen as two independent objectives.

An application of the spatial equilibrium model to soybean production in tocantins and neighboring states in Brazil

In the production chain of soybeans in Brazil a sizable part of the corresponding cost structure is the result of logistics costs. Given the location of its production sites, distant from the ocean, the optimization of the transportation costs is essential for preserving competitiveness. Using nonlinear programming, this study proposes a spatial multimodal and temporal equilibrium model. The applicability of the model is tested with a case study regarding the exports of the soybeans produced in three states in the northern part of the Brazilian cerrado region. In the state of Tocantins, the effects of infrastructure investments in the competitiveness of the production are described through four proposed scenarios, while the basic scenario compares the three states. The data are treated using the GAMS/MINOS program. The study asserts that soybean production will be more competitive if warehousing facilities are used extensively and when the project hydroway becomes operational.

Location model of specialized terminals for soybe an exports in Brazil

The purpose of this work is the development of a location model for specialized terminals used as transshipment points in the supply chain of soybeans. The theoretical basis of the study relies on the association of a transshipment model with a multi-commodity, multi-facility capacitated location model. The shipping ports might be seen as specialized terminals that add value to the exported products by transforming raw soy grains into soy oil and soy meal. The proposed model also considers service activities in each terminal and the capacity of the maritime ports. Using representative data from the year 2004, the model is illustrated by a small case study, which considers six points of production in inland Brazil, all served by railways, one maritime port on the north and five on the east coast, and three destination ports in Europe and Asia. The study includes a rough sensitivity analysis regarding volumes, capacities, prices, and transportation costs

Strategic alliances: tools for constructing the future

Purpose – The purpose of this article is to develop a methodology for the identification of a desired normative scenario, acceptable and feasible, based on a set of prospective scenarios.Design/methodology/approach – This paper presents strategic alliances as one fundamental tool in the process of constructing the future. The alliances are based on prospective scenarios, within strategic interactions.Findings – The central key is the view of the most probable future as a NASH balance point. This point identifies not only a balance of forces, but also the negotiation limits for each actor and therefore the strategic alliances possible. The alliances, if achieved, create a “super actor”, destabilizing the original balance, and creating a new balance point, and therefore a more likely new future.Originality/value – This article develops a methodology for the identification of a desired normative scenario, acceptable and feasible, based on a set of prospective scenarios.

Case study: improving industrial competitiveness: a TSP approach

This paper describes a case study in a chemical company in which management was concerned with low productivity and the inability to keep pace with demand. A description of the company and an assessment of its competitiveness are outlined. To improve productivity and to help management solve the firm’s production scheduling problem, a proposal was developed based on the travelling salesman problem with adjustments for earliness and lateness costs over due dates of the orders. Management involvement is discussed.

The air transportation hub-and-spoke design problem: comparison between a continuous and a discrete solution method

The hub-and-spoke network design problem, also known as the hub location problem, aims to find the concentration points in a given network flow so that the sum of the distances of the linkages is minimized. In this work, we compare discrete solutions of this problem, given by the branch-and-cut method applied to the p-hub median model, with continuous solutions, given by the hyperbolic smoothing technique applied to a min-sum-min model. Computational experiments for particular instances of the Brazilian air transportation system, with the number of hubs varying from 2 to 8, are conducted with the support of a discretization heuristic and the Voronoi diagram.