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Full-Text Articles in Physical Sciences and Mathematics
Darwin: A Ground Truth Agnostic Captcha Generator Using Evolutionary Algorithm, Eric Y. Chen, Lin-Shung Huang, Ole J. Mengshoel, Jason D. Lohn
Darwin: A Ground Truth Agnostic Captcha Generator Using Evolutionary Algorithm, Eric Y. Chen, Lin-Shung Huang, Ole J. Mengshoel, Jason D. Lohn
Ole J Mengshoel
We designed and implemented Darwin, the first CAPTCHA generator using evolutionary algorithm. We evaluated the effectiveness of our proposed CAPTCHAs with MTurk users (non-attackers) and Antigate workers (attackers). Due to our ground-truth agnostic fitness function, we are able to discover a new category of CAPTCHAs in which attackers answer correctly but non-attackers answer incorrectly.
Feedback Control For Multi-Modal Optimization Using Genetic Algorithms, Jun Shi, Ole J. Mengshoel, Dipan K. Pal
Feedback Control For Multi-Modal Optimization Using Genetic Algorithms, Jun Shi, Ole J. Mengshoel, Dipan K. Pal
Ole J Mengshoel
Many optimization problems are multi-modal. In certain cases, we are interested in finding multiple locally optimal solutions rather than just a single optimum as is computed by traditional genetic algorithms (GAs). Several niching techniques have been developed that seek to find multiple such local optima. These techniques, which include sharing and crowding, are clearly powerful and useful. But they do not explicitly let the user control the number of local optima being computed, which we believe to be an important capability.
In this paper, we develop a method that provides, as an input parameter to niching, the desired number of …