A frequent task in educational settings is to assign students to groups based on stated preferences for some projects or topics. This paper introduces a web-based tool supporting both the work flow of collecting stude...
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A frequent task in educational settings is to assign students to groups based on stated preferences for some projects or topics. This paper introduces a web-based tool supporting both the work flow of collecting student data and the group formation. The latter is based on finding optimal solutions to suitable mathematical assignmentproblems, allowing for a number of constraints regarding size and structure of the groups. Evaluation results show advantages compared to manual procedures in terms of time savings for lecturers, and higher fairness and correctness as perceived by students. (C) 2009 Elsevier Ltd. All rights reserved.
A zero element row augmenting path algorithm is proposed for linearassignment *** the algorithm,the maximum element in an assignment y is picked firstly,where y is calculated according to the reduced matrix of a give...
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ISBN:
(纸本)9781467397155
A zero element row augmenting path algorithm is proposed for linearassignment *** the algorithm,the maximum element in an assignment y is picked firstly,where y is calculated according to the reduced matrix of a given cost matrix at the initial *** to each row's zero element record and starting from the row containing the picked element,a zero element row augmenting path is computed while the cost matrix is further reduced and the zero element record of each row is ***,y is adjusted according to the augmenting path so that the number of the zero elements in y can increase *** above process is repeated until y is an optimal *** computational experiments are carried out and indicate that the proposed algorithm is even faster than the shortest augmenting algorithm.
We discuss bit error rate (BER) minimization problems in multiple amplify-and-forward (AF) relay-assisted or-thogonal frequency-division multiplexing (OFDM) system over frequency-selective fading channels with total p...
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We discuss bit error rate (BER) minimization problems in multiple amplify-and-forward (AF) relay-assisted or-thogonal frequency-division multiplexing (OFDM) system over frequency-selective fading channels with total power and individual power constraints, respectively. A joint optimization method of power loading, relay selection and subcarrier pairing is solicited to solve the problems with respect to the above two power constraint conditions. Particularly, we transform subcarrier pairing into a linear assignment problem and apply Jonker-Volgenant (JV) algorithm to deal with it. A simulation result demonstrates superior performances of our algorithm to those of other schemes for different relay locations.
linear regression without correspondences concerns the recovery of a signal in the linear regression setting, where the correspondences between the observations and the linear functionals are unknown. The associated m...
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linear regression without correspondences concerns the recovery of a signal in the linear regression setting, where the correspondences between the observations and the linear functionals are unknown. The associated maximum likelihood function is NP-hard to compute when the signal has dimension larger than one. To optimize this objective function we reformulate it as a concave minimization problem, which we solve via branch-and-bound. This is supported by a computable search space to branch, an effective lower bounding scheme via convex envelope minimization and a refined upper bound, all naturally arising from the concave minimization reformulation. The resulting algorithm outperforms state-of-the-art methods for fully shuffled data and remains tractable for up to 8-dimensional signals, an untouched regime in prior work.
We propose a new point matching algorithm in this letter by minimizing a concave geometric matching cost function coming from the objective function of the robust point matching algorithm. Due to concavity of this fun...
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We propose a new point matching algorithm in this letter by minimizing a concave geometric matching cost function coming from the objective function of the robust point matching algorithm. Due to concavity of this function, naive optimization strategies such as gradient descent will fail. To address this problem, we use a path following strategy for optimization which works by adding a convex quadratic term to the objective function and then gradually transitioning from the state that there is only weight of the convex term to the state that there is only weight of the concave geometric matching cost term. Extensive experimental results demonstrate strong robustness of the method over several state-of-the-art methods and it also has good computational efficiency.
Analysis of random instances of optimization problems provides valuable insights into the behavior and properties of problem's solutions, feasible region, and optimal values, especially in large-scale cases. A cla...
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Analysis of random instances of optimization problems provides valuable insights into the behavior and properties of problem's solutions, feasible region, and optimal values, especially in large-scale cases. A class of problems that have been studied extensively in the literature using the methods of probabilistic analysis is represented by the assignmentproblems, and many important problems in operations research and computer science can be formulated as assignmentproblems. This paper presents an overview of the recent results and developments in the area of probabilistic assignmentproblems, including the linear and multidimensional assignmentproblems, quadratic assignmentproblem, etc. (c) 2007 Elsevier B.V. All rights reserved.
We propose a novel multitarget tracking framework for Myosin VI protein molecules in total internal reflection fluorescence microscopy sequences which integrates an extended Hungarian algorithm with an interacting mul...
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We propose a novel multitarget tracking framework for Myosin VI protein molecules in total internal reflection fluorescence microscopy sequences which integrates an extended Hungarian algorithm with an interacting multiple model filter. The extended Hungarian algorithm, which is a linear assignment problem based method, helps to solve measurement assignment and spot association problems commonly encountered when dealing with multiple targets, although a two-motion model interacting multiple model filter increases the tracking accuracy by modelling the nonlinear dynamics of Myosin VI protein molecules on actin filaments. The evaluation of our tracking framework is conducted on both real and synthetic total internal reflection fluorescence microscopy sequences. The results show that the framework achieves higher tracking accuracies compared to the state-of-the-art tracking methods, especially for sequences with high spot density.
Feature allocation models postulate a sampling distribution whose parameters are derived from shared features. Bayesian models place a prior distribution on the feature allocation, and Markov chain Monte Carlo is typi...
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Feature allocation models postulate a sampling distribution whose parameters are derived from shared features. Bayesian models place a prior distribution on the feature allocation, and Markov chain Monte Carlo is typically used for model fitting, which results in thousands of feature allocations sampled from the posterior distribution. Based on these samples, we propose a method to provide a point estimate of a latent feature allocation. First, we introduce FARO loss, a function between feature allocations which satisfies quasi-metric properties and allows for comparing feature allocations with differing numbers of features. The loss involves finding the optimal feature ordering among all possible orderings, but computational feasibility is achieved by framing this task as a linear assignment problem. We also introduce the FANGS algorithm to obtain a Bayes estimate by minimizing the Monte Carlo estimate of the posterior expected FARO loss using the available samples. FANGS can produce an estimate other than those visited in the Markov chain. We provide an investigation of existing methods and our proposed methods. Our loss function and search algorithm are implemented in the fangs package in R.
Encouraged by the study of extremal limits for sums of the form lim(N ->) (infinity) 1/N Sigma(N)(n=1) c(x(n), y(n)) with uniformly distributed sequences {x(n)}, {y(n)} the following extremal problem is of interest...
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Encouraged by the study of extremal limits for sums of the form lim(N ->) (infinity) 1/N Sigma(N)(n=1) c(x(n), y(n)) with uniformly distributed sequences {x(n)}, {y(n)} the following extremal problem is of interest max(gamma) integral([0,1]2) c(x, y) gamma (dx, dy), for probability measures gamma on the unit square with uniform marginals, i.e., measures whose distribution function is a copula. The aim of this article is to relate this problem to combinatorial optimization and to the theory of optimal transport. Using different characterizations of maximizing gamma's one can give alternative proofs of some results from the field of uniform distribution theory and beyond that treat additional questions. Finally, some applications to mathematical finance are addressed. (C) 2015 Royal Dutch Mathematical Society (KWG). Published by Elsevier B.V. All rights reserved.
This paper presents a one-layer recurrent neural network for solving linear programming problems. The proposed neural network is guaranteed to be globally convergent in finite time to the optimal solutions under a mil...
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ISBN:
(纸本)9783642217371;9783642217388
This paper presents a one-layer recurrent neural network for solving linear programming problems. The proposed neural network is guaranteed to be globally convergent in finite time to the optimal solutions under a mild condition on a derived lower bound of a single gain parameter. The number of neurons in the neural network is the same as the number of decision variables of the dual optimization problem. Compared with the existing neural networks for linear programming, the proposed neural network has salient features such as finite-time convergence and lower model complexity. Specifically, the proposed neural network is tailored for solving the linear assignment problem with simulation results to demonstrate the effectiveness and characteristics of the proposed neural network.
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