P. N. Smith

Fuzzy evaluation of land-use and transportation options

A methodology is presented for the evaluation of discrete transportation options characterised along multiple dimensions based on fuzzy and linguistic variables. In particular, the methodology recognises the possibility of degrees of uncertainty or imprecision surrounding the outcomes of each option with respect to each dimension and classifies outcomes (or equivalently, dimensions) as ‘quantitative precise’, ‘quantitative imprecise’, and ‘subjective’ (qualitative). Outcomes in the subjective class are represented in terms of linguistic variables whereas those in the first two classes are represented in terms of nonfuzzy (crisp) variables and fuzzy variables, respectively. To illustrate the methodology, an example relating to the evaluation of three transportation options for the small town of Kuranda, North Queensland, Australia, is presented.

Flexible aggregation in multiple attribute decision making: Application to the Kuranda Range Road Upgrade

The conventional method of aggregating the satisfaction of transport projects with respect to multiple attributes is commonly some variant of Simple Additive Weighting (SAW), which involves the sum of products of standardized outcomes of projects with respect to attributes and attribute importance weights. It is suggested that alternative forms of aggregation might be more useful, in particular, the Ordered Weighted Averaging (OWA) operator introduced by Yager (1988). Attribute importance weights and satisfaction of attributes by projects may be aggregated prior to aggregation via an OWA operator. In this case OWA operator weights may be based on the “attitudinal character” of the decision maker expressed in terms of the degree of “orness” and “andness” of the aggregation. A well-known approach is maximum entropy aggregation, in which weights are derived to be as “even” (or as minimally dispersed) as a possible subject to satisfying a given “orness” or “andness” constraint. Recently, aggregation processes have been proposed by Larsen (1999 2002 2003) which have several desirable properties and also may be considered as alternative forms of aggregation. An example is given relating to the Kuranda Range Road upgrade (Queensland, Australia) which is limited by grade, poor overtaking opportunities, poor horizontal alignment, and other constraints, and the road is expected to become increasingly congested over the next few years. A more flexible Multiple Attribute Decision Making is used to identify a “best” project from a set of four alternative projects.

If planning is about anything, what is it about?

The discipline and practice of regional and town planning is searching uneasily for new directions attendant upon conceptual and empirical developments since the early 1970s. This paper traces the current disquiet, explores contemporary viewpoints and then outlines a prospective focus in terms of processes of wealth creation. It is argued that orientation to this goal would realign planning with other mainstream disciplines such as economics and provide greater clarity to the endeavours of theoreticians and practitioners. The implications of such a move are explored in terms of an approach to the real world of the marketplace.

Environmental project evaluation: A fuzzy logic based method

The paper illustrates the potential of fuzzy logic and approximate reasoning in the context of the evaluation of a set of transport projects characterized in terms of multiple environmental factors or impacts. A method involving fragments of imprecise information (conditional propositions, implications), where antecedents are environmental impacts or factors and the consequent is a measure of satisfaction associated with those factors, is illustrated in the context of the evaluation of road projects. Each factor is defined as a fuzzy subset of the set of projects. A simple example is given involving four road projects and six factors (travel-time saved, social impact, flora/fauna impact, noise impact, air quality impact, capital cost).

AN APPLICATION OF FUZZY SETS TO TRANSPORT PROJECT APPRAISAL

Abstract This paper reviews some of the theory continuous fuzzy sets or subsets and illustrates, by way of example, an application to project appraisal in land use and transportation planning. In particular, a detailed illustration of the application of continuous fuzzy sets (fuzzy numbers) to the assessment of four alternative routes for a part of a proposed Eastern Corridor between the Cities of Brisbane and the Gold Coast, Queensland, Australia, is presented.

Land-use Mitigation Strategies for Storm Surge Risk in South East Queensland

Abstract South East Queenslands (SEQ) potential exposure to tropical cyclone and storm surge events provides a significant dilemma for coastal settlements and their communities. It is essential for the long-term viability of SEQs coastal settlements that effective land-use strategies are developed and implemented. This study develops a comprehensive land-use response that is capable of identifying suitable levels of planning response to potential hazard risks.

Fuzzy applications in project appraisal: Part 1 discrete fuzzy sets

This paper reviews some of the theory of discrete Juzzy sets or subsets and illustrates, by way of simple examples, some applications to project appraisal in the context of environmental planning.

Approximate reasoning in transport project evaluation

The paper illustrates the potential of approximate reasoning and fuzzy logic in the evaluation of transport projects where projects are characterised in terms of multiple factors or characteristics. A method is illustrated which incorporates fragments of imprecise information (conditional propositions, implications). The antecedents in each fragment involve factors of environmental significance and the consequent is a measure of satisfaction associated with those factors. Factors may be either quantitative or qualitative.

Applications of intuitionistic fuzzy set aggregation operators in transport multi-factor project evaluation

Abstract An intuitionistic fuzzy set (IFS) is a generalisation of a fuzzy set characterised by a truth membership function and a false membership function. The former is a lower bound on the grade of membership of the evidence in favour of a particular element belonging to the set and the latter is a lower bound on the negation of that element belonging to the set derived from evidence against that element belonging to the set. A similar concept is a vague set, though vague sets have been shown to be identical to IFSs. In the context of project evaluation, an IFS may be used to represent the degree to which a project satisfies a criterion and the degree to which it does not. Aggregation of such IFSs has been considered in recent years to identify a best project in terms of several criteria or factors. A particular desirable way to aggregate IFS is in terms of an ordered weighted average (OWA) which can be expressed in different forms such as arithmetic and geometric. In an OWA operator, weights are applied to the position of an element in the aggregation. In addition, hybrid OWA operators may be developed to not only weight the position of elements in the aggregation but the element itself. An example is given relating to the Kuranda Range Road upgrade (Queensland, Australia) which is limited by grade, poor overtaking opportunities, poor horizontal alignment and other constraints and the road is expected to become increasingly congested over the next few years. A more flexible multi-factor decision method is used to identify a ‘best’ project from a set of four alternative projects.

Alternative forms of aggregation in the analytic hierarchy process: Ordered weighted averaging operators

The analytic hierarchy process (AHP) methodology was introduced by Thomas Saaty and has had numerous applications in a wide range of contexts. In a common three-level hierarchy, AHP involves the aggregation of criterion importance weights (or priorities) and the performance scores (or priorities) of alternatives as the sum of the products of weights and scores for each alternative. The multiplicative AHP (MAHP) involves the multiplicative aggregation of performance scores raised to the power of the criterion weights and has been seen by many individuals (notably, Freerk Lootsma and John Barzilai) as an alternative more desirable structure. It is suggested that alternative forms of aggregation of performance scores and criterion weights might be more useful, in particular the ordered weighted averaging (OWA) operator introduced by Ronald Yager. The choice of weights in an OWA operator may be guided by a linguistic quantifier involving the importance weights associated with each criterion. The geometric ordered weighted averaging (GOWA) operator is also considered as a possibility for aggregation in the MAHP. An example is given relating to the location of a Green Bridge Link (for public transport and non-motorized modes of transport) in Brisbane, Queensland, Australia. The four approaches (alternatives) to the identified site of the Green Bridge (Dutton Park) are a Full Busway, Boggo Road, Cornwall Street, and Kent Street.