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Machine learning has been increasingly applied in identification of fraudulent transactions. However, most application systems can only detect the incidents after they have already occurred, not at or near real time. As spurious transactions are far fewer than the normal ones, the highly imbalanced data makes fraud detection even more challenging. This study has proposed a detection framework and implemented it using Support Vector Machine (SVM) enhanced with quantum annealing solvers. To evaluate its detection performance and examine the impact of feature selection, we have applied this quantum machine learning (QML) system along with systems built with twelve traditional machine learning methods on two datasets: Israel credit card transactions (non-time series) which is moderately imbalanced and a bank loan dataset (time series) that is highly imbalanced. The result shows that, the quantum enhanced SVM has categorically outperformed the rest in both speed and accuracy with the bank loan dataset. However, it's detection accuracy is similar to others with Israel credit card transactions data. Furthermore, for both datasets, feature selection has been shown to significantly improve the detection speed, although the improvement on accuracy is marginal. These findings have demonstrated the potential of QML applications on time series based, highly imbalanced data, and the merit of traditional machine learning approaches in non-time series data. This study provides insight on selecting appropriate approach with different types of datasets while taking the tradeoffs of speed, accuracy, and cost into consideration.

Modern metaheuristic methodologies rely on well defined neighborhood structures and efficient means for evaluating potential moves within these structures. Move mechanisms range in complexity from simple 1-flip procedures where binary variables are “flipped” one at a time, to more expensive, but more powerful, r-flip approaches where “r” variables are simultaneously flipped. These multi-exchange neighborhood search strategies have proven to be effective approaches for solving a variety of combinatorial optimization problems. In this paper, we present a series of theorems based on partial derivatives that can be readily adopted to form the essential part of r-flip heuristic search methods for Pseudo-Boolean optimization. To illustrate the use of these results, we present preliminary results obtained from four simple heuristics designed to solve a set of Max 3-SAT problems.

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In this paper, we are concerned with the problem of scheduling n jobs on m machines. The job processing rate is interdependent and the jobs are non-preemptive. During the last several decades, a number of related models for parallel machine scheduling with interdependent processing rates (PMS-IPR) have appeared in the scheduling literature. Some of these models have been studied independently from one another. The purpose of this paper is to present two general PMS-IPR models that capture the essence of many of these existing PMS-IPR models. Several new complexity results are presented. We discuss improvements on some existing models. Furthermore, for an extension of the two related PMS-IPR models where they include many resource constraint models with controllable processing times, we propose an efficient dynamic programming procedure that solves the problem to optimality.