Effectiveness of an alternative model for establishing mesopic luminance

To determine mesopic luminance for a given photopic luminance and scotopic/photopic (S/P) ratio, the Commission Internationale de l’Eclairage (CIE) recommended system utilizes an equation. Whilst being accurate, it requires several iterations to achieve a stable result and requires the use of an adaptation coefficient. This article proposes an alternative approach, a model developed using a Rational Taylor function which does not require either iteration or an adaptation coefficient. Road lighting tends to use average photopic luminances in the range of 0.1 to 3 cd/m2; within this range, the model has an average error of 0.28% against the iteration approach, which is sufficient for most practical purposes.

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Illuminance Reconstruction of Road Lighting in Urban Areas for Efficient and Healthy Lighting Performance Evaluation

Applied Sciences ◽

10.3390/app8091646 ◽

2018 ◽

Vol 8 (9) ◽

pp. 1646 ◽

Cited By ~ 4

Author(s):

Qi Yao ◽

Hongbing Wang ◽

Jim Uttley ◽

Xiaobo Zhuang

Keyword(s):

Urban Areas ◽

Average Error ◽

Feature Points ◽

Human Beings ◽

System Technology ◽

Practical Applications ◽

Road Lighting ◽

Information System Technology ◽

Traditional Approaches ◽

Model Approach

Big lighting data are required for evaluation of lighting performance and impacts on human beings, environment, and ecology for smart urban lighting. However, traditional approaches of measuring road lighting cannot achieve this aim. We propose a rule-of-thumb model approach based on some feature points to reconstruct road lighting in urban areas. We validated the reconstructed illuminance with both software simulated and real road lighting scenes, and the average error is between 6 and 19%. This precision is acceptable in practical applications. Using this approach, we reconstructed the illuminance of three real road lighting environments in a block and further estimated the mesopic luminance and melanopic illuminance performance. In the future, by virtue of Geographic Information System technology, the approach may provide big lighting data for evaluation and analysis, and help build smarter urban lighting.

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ALTERNATIVE REPRESENTATION OF FUZZY COALITIONS

International Journal of Uncertainty Fuzziness and Knowledge-Based Systems ◽

10.1142/s0218488509005917 ◽

2009 ◽

Vol 17 (03) ◽

pp. 345-364 ◽

Cited By ~ 1

Author(s):

MILAN MAREŠ ◽

MILAN VLACH

Keyword(s):

Cooperative Games ◽

Alternative Model ◽

Common Interest ◽

Compact Groups ◽

Alternative Representation ◽

Alternative Approach ◽

Individual Player ◽

Fuzzy Coalitions ◽

Fuzzy Subsets

The theory of cooperative games with vague cooperation is based on modelling fuzzy coalitions as fuzzy subsets of the set of all players who participate in the coalitions with some part of their "power". Here, we suggest an alternative approach assuming that coalitions are formed by relatively compact groups of individual players each of which represents a specific common interest. Each individual player may participate in several such groups and, as their member, in several coalitions. Our aim is to show that such an alternative model of fuzzy coalitions, in spite of its seemingly higher complexity, offers an interesting more sophisticated reflection of the structure of vague cooperation and of relations being in its background.

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Basic Evolutionary Approach to the Traveling Salesman Problem

U Porto Journal of Engineering ◽

10.24840/2183-6493_001.002_0004 ◽

2018 ◽

Vol 1 (2) ◽

pp. 30-38

Author(s):

Débora Regina De São José ◽

Mauricio Garcia Hernandez

Keyword(s):

Traveling Salesman Problem ◽

Evolutionary Programming ◽

Traveling Salesman ◽

Evolutionary Approach ◽

Average Error ◽

Test Case ◽

Simple Simulation ◽

Alternative Approach ◽

Benchmark Instances ◽

The Traveling Salesman Problem

Evolutionary programming (EP) is a metaheuristic method developed as an alternative approach to artificial intelligence. The aim of this paper is to bring an introduction to EP algorithms through the implementation of the basic D. B. Fogel’s Evolutionary Programing approach of 1988 and the emulation of his results in order to analyze the performance of the evolutionary programming method on solving a benchmark test case. The EP approach is implemented thru a simple simulation of natural evolution and the allowance of probabilistic survival of individuals. The novelty of this paper relies on testing the algorithm performance in some problems of well-known benchmark instances of the Traveling Salesman Problem, where that 1988 evolutionary approach was not tested. The reproduction of 1988 D. B. Fogel’s approach was possible, the found average error of this method for 200000 offspring applied to the benchmark instances was found to be in the order of the 10%.

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