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1 – 10 of over 1000Traffic signal control is one of the oldest application areas of fuzzy sets in transportation. In general, fuzzy control is found to be superior in complex problems with…
Abstract
Traffic signal control is one of the oldest application areas of fuzzy sets in transportation. In general, fuzzy control is found to be superior in complex problems with multi-objective decisions. In traffic signal control, several traffic flows compete for the same time and space, and different priorities are often set to different traffic flows or vehicle groups
The public transport priorities are a very important part of the effective traffic signal control. Normally, the public transport priorities are programmed by using special algorithms, which are tailor-made for each intersection. The experiences have proved that this kind of algorithms can be very effective if some compensation algorithms and the traffic-actuated control mode are used. We believe that using the fuzzified public transport priority algorithms, the measures of effectiveness of traffic signal control can be even better. In this paper, our fuzzy control algorithm of the public transport priorities will be presented.
Tessa Sayers, Jessica Anderson and Michael Bell
The increasing awareness of the importance of the wider objectives of traffic management and control has led to the work described in this paper. The aim of the study is to…
Abstract
The increasing awareness of the importance of the wider objectives of traffic management and control has led to the work described in this paper. The aim of the study is to develop a flexible signal controller which may be configured so that it embodies the objectives appropriate for the situation in which it is to be used. This paper describes the optimisation of a prototype fuzzy logic signal controller with respect to several criteria simultaneously. Having demonstrated the controller's sensitivity to changes in its parameters, a multiobjective genetic algorithm (MOGA) optimisation technique is used to derive a family of solutions, each of which is optimal with respect to at least one of the criteria, whilst minimising the trade-off with respect to the other criteria.
Joshua B Levy and Eunsang Yoon
Researchers and practitioners of international market entry typically have a difficult task obtaining and processing requisite information to evaluate potential opportunities and…
Abstract
Researchers and practitioners of international market entry typically have a difficult task obtaining and processing requisite information to evaluate potential opportunities and risks. Essential analysis is often confounded by inappropriate measures of input requirements, inadequately defined information categories, and the overall complex nature of the decision process. In partial response to these issues, this research introduces a three-stage guiding framework for market-entry decision and presents alternative methodologies for country risk assessment, a principal component in the final stage. A variety of discrete methods are included such as subjective interaction by deliberating experts, scoring models, the analytic hierarchy process, simulation, and statistical designs using regression or factor analysis. New analytic rule-based nondiscrete techniques utilizing fuzzy logic are also introduced. Fuzzy logic simulates natural discourse and analogical reasoning through inference about nebulous facts and inexact concepts, using rules that do not require a perfect match between input data and their antecedental values in order to fire. It provides formal mathematical structure for representing, evaluating, and interpreting linguistic context. It is especially useful for handling problematical issues such as imprecise data, ambiguous information, vague meanings of terms, and inconsistent analyses that characterize the general market-entry problem and risk assessment in particular. Numerical examples demonstrate how discrete and fuzzy models work to integrate political, social, and financial risks.
The need to design buildings with due consideration for bioclimatic and passive design is central to promoting sustainability in the built environment from an energy perspective…
Abstract
The need to design buildings with due consideration for bioclimatic and passive design is central to promoting sustainability in the built environment from an energy perspective. Indeed, the energy and atmosphere considerations in building design, construction and operation have received the highest consideration in green building frameworks such as LEED and BREEAM to promote SDG 9: Industry, Innovation and Infrastructure and SDG 11: Sustainable Cities and Communities and contributing directly to support SDG 13: Climate Action. The research literature is rich of findings on the efficacy of passive measures in different climate contexts, but given that these measures are highly dependent on the prevailing weather conditions, which is constantly in evolution, disturbed by the climate change phenomenon, there is pressing need to be able to accurately predict such changes in the short (to the minute) and medium (to the hour and day) terms, where AI algorithms can be effectively applied. The dynamics of the weather patterns over seasons, but more crucially over a given season means that optimum response of building envelope elements, specifically through the passive elements, can be reaped if these passive measures can be adapted according to the ambient weather conditions. The use of representative mechatronics systems to intelligently control certain passive measures is presented, together with the potential use of artificial intelligence (AI) algorithms to capture the complex building physics involved to predict the expected effect of weather conditions on the indoor environmental conditions.
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In the last few decades, there has been growing interest in forecasting with computer intelligence, and both fuzzy time series (FTS) and artificial neural networks (ANNs) have…
Abstract
In the last few decades, there has been growing interest in forecasting with computer intelligence, and both fuzzy time series (FTS) and artificial neural networks (ANNs) have gained particular popularity, among others. Rather than the conventional methods (e.g., econometrics), FTS and ANN are usually thought to be immune to fundamental concepts such as stationarity, theoretical causality, post-sample control, among others. On the other hand, a number of studies significantly indicated that these fundamental controls are required in terms of the theory of forecasting, and even application of such essential procedures substantially improves the forecasting accuracy. The aim of this paper is to fill the existing gap on modeling and forecasting in the FTS and ANN methods and figure out the fundamental concepts in a comprehensive work through merits and common failures in the literature. In addition to these merits, this paper may also be a guideline for eliminating unethical empirical settings in the forecasting studies.
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Aminah Robinson Fayek and Rodolfo Lourenzutti
Construction is a highly dynamic environment with numerous interacting factors that affect construction processes and decisions. Uncertainty is inherent in most aspects of…
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Construction is a highly dynamic environment with numerous interacting factors that affect construction processes and decisions. Uncertainty is inherent in most aspects of construction engineering and management, and traditionally, it has been treated as a random phenomenon. However, there are many types of uncertainty that are not naturally modelled by probability theory, such as subjectivity, ambiguity and vagueness. Fuzzy logic provides an approach for handling such uncertainties. However, fuzzy logic alone has some limitations, including its inability to learn from data and its extensive reliance on expert knowledge. To address these limitations, fuzzy logic has been combined with other techniques to create fuzzy hybrid techniques, which have helped solve complex problems in construction. In this chapter, a background on fuzzy logic in the context of construction engineering and management applications is presented. The chapter provides an introduction to uncertainty in construction and illustrates how fuzzy logic can improve construction modelling and decision-making. The role of fuzzy logic in representing uncertainty is contrasted with that of probability theory. Introductory material is presented on key definitions, properties and methods of fuzzy logic, including the definition and representation of fuzzy sets and membership functions, basic operations on fuzzy sets, fuzzy relations and compositions, defuzzification methods, entropy for fuzzy sets, fuzzy numbers, methods for the specification of membership functions and fuzzy rule-based systems. Finally, a discussion on the need for fuzzy hybrid modelling in construction applications is presented, and future research directions are proposed.
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Zhengbing Hu, Yevgeniy V. Bodyanskiy and Oleksii K. Tyshchenko