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    30 March 2014, Volume 2 Issue 1
    Management Science
    Competitive Communication Spectrum Economy and Equilibrium
    Yin-Yu Ye
    2014, 2(1):  1-16.  doi:10.1007/s40305-013-0028-5
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    Consider a competitive “spectrum economy” in a communication system
    where multiple users share a common frequency band and each of them, equipped
    with an endowed “monetary” budget, will “purchase” its own transmit power spectrum
    (taking others as given) in maximizing its Shannon utility or pay-off function
    that includes the effects of interference and subjects to its budget constraint. A market
    equilibrium is a price spectrum and a frequency power allocation that independently
    and simultaneously maximizes each user’s utility. Furthermore, under an equilibrium
    the market clears, meaning that the total power demand equals the power supply for
    every user and every frequency. We prove that such an equilibrium always exists for
    a discretized version of the problem, and, under a weak-interference condition or the
    Frequency Division Multiple Access (FMDA) policy, the equilibrium can be computed
    in polynomial time. This model may lead to an efficient decentralized method
    for spectrum allocation management and optimization in achieving both higher social
    utilization and better individual satisfaction. Furthermore, we consider a trading
    market among individual users to exchange their endowed power spectrum under a
    price mechanism, and we show that the market price equilibrium also exists and it
    may lead to a more socially desired spectrum allocation.

    Quadratic Optimization over a Second-Order Cone with Linear Equality Constraints
    Xiao-ling Guo · Zhi-bin Deng · Shu-Cherng Fang · Zhen-boWang ·Wen-xun Xing
    2014, 2(1):  17-38.  doi:10.1007/s40305-013-0035-6
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    This paper studies the nonhomogeneous quadratic programming problem
    over a second-order cone with linear equality constraints. When the feasible region
    is bounded, we show that an optimal solution of the problem can be found in polynomial
    time. When the feasible region is unbounded, a semidefinite programming
    (SDP) reformulation is constructed to find the optimal objective value of the original
    problem in polynomial time. In addition, we provide two sufficient conditions, under
    which, if the optimal objective value is finite, we show the optimal solution of SDP
    reformulation can be decomposed into the original space to generate an optimal solution
    of the original problem in polynomial time. Otherwise, a recession direction
    can be identified in polynomial time. Numerical examples are included to illustrate
    the effectiveness of the proposed approach.

    Continuous Optimization
    Analysis of Sparse Quasi-Newton Updates with Positive Definite Matrix Completion
    Yu-Hong Dai · Nobuo Yamashita
    2014, 2(1):  39-56.  doi:10.1007/s40305-014-0039-x
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    Based on the idea of maximum determinant positive definite matrix
    completion, Yamashita (Math Prog 115(1):1–30, 2008) proposed a new sparse
    quasi-Newton update, called MCQN, for unconstrained optimization problems with
    sparse Hessian structures. In exchange of the relaxation of the secant equation, the
    MCQN update avoids solving difficult subproblems and overcomes the ill-conditioning
    of approximate Hessian matrices. However, local and superlinear convergence
    results were only established for the MCQN update with the DFP method. In
    this paper, we extend the convergence result to the MCQN update with the whole
    Broyden’s convex family. Numerical results are also reported, which suggest some
    efficient ways of choosing the parameter in the MCQN update the Broyden’s family.

    Consensus Proximal Support Vector Machine for Classification Problems with Sparse Solutions
    Yan-Qin Bai · Yan-Jun Shen · Kai-Ji Shen
    2014, 2(1):  57-74.  doi:10.1007/s40305-014-0037-z
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    Classification problem is the central problem in machine learning.
    Support vector machines (SVMs) are supervised learning models with associated
    learning algorithms and are used for classification in machine learning. In this paper,
    we establish two consensus proximal support vector machines (PSVMs) models,
    based on methods for binary classification. The first one is to separate the objective
    functions into individual convex functions by using the number of the sample points
    of the training set. The constraints contain two types of the equations with global
    variables and local variables corresponding to the consensus points and sample
    points, respectively. To get more sparse solutions, the second one is l1–l2 consensus
    PSVMs in which the objective function contains an ‘1-norm term and an ‘2-norm
    term which is responsible for the good classification performance while ‘1-norm
    term plays an important role in finding the sparse solutions. Two consensus PSVMs
    are solved by the alternating direction method of multipliers. Furthermore, they are
    implemented by the real-world data taken from the University of California, Irvine
    Machine Learning Repository (UCI Repository) and are compared with the existed
    models such as ‘1-PSVM, ‘p-PSVM, GEPSVM, PSVM, and SVM-light. Numerical
    results show that our models outperform others with the classification accuracy and
    the sparse solutions.

    An Exact l_1 Exponential Penalty Function Method for Multiobjective Optimization Problems with Exponential-Type Invexity
    Anurag Jayswal · Sarita Choudhury
    2014, 2(1):  75-92.  doi:10.1007/s40305-014-0038-y
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    The purpose of this paper is to devise exact l_1 exponential penalty
    function method to solve multiobjective optimization problems with exponentialtype
    invexity. The conditions governing the equivalence of the (weak) efficient
    solutions to the vector optimization problem and the (weak) efficient solutions to
    associated unconstrained exponential penalized multiobjective optimization problem
    are studied. Examples are given to illustrate the obtained results.

    A New Objective Penalty Function Approach for Solving Constrained Minimax Problems
    Jue-You Li · Zhi-You Wu · Qiang Long
    2014, 2(1):  93-108.  doi:10.1007/s40305-014-0041-3
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    In this paper, a new objective penalty function approach is proposed for
    solving minimax programming problems with equality and inequality constraints.
    This new objective penalty function combines the objective penalty and constraint
    penalty. By the new objective penalty function, a constrained minimax problem is
    converted to minimizations of a sequence of continuously differentiable functions
    with a simple box constraint. One can thus apply any efficient gradient minimization
    methods to solve the minimizations with box constraint at each step of the sequence.
    Some relationships between the original constrained minimax problem and the
    corresponding minimization problems with box constraint are established. Based on
    these results, an algorithm for finding a global solution of the constrained minimax
    problems is proposed by integrating the particular structure of minimax problems
    and its global convergence is proved under some conditions. Furthermore, an
    algorithm is developed for finding a local solution of the constrained minimax of numerical experiments with well-known test problems show that satisfactorily
    approximate solutions for some constrained minimax problems can be obtained.
    problems, with its convergence proved under certain conditions. Preliminary results

    Discrete Optimization
    Hybrid Flowshop Scheduling with Interstage Job Transportation
    Wei-Ya Zhong · Long-Hua Lv
    2014, 2(1):  109-122.  doi:10.1007/s40305-014-0040-4
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    There are a variety of joint job production and transportation scheduling
    problems that arise in modern manufacturing systems. In this paper, we study one of
    such problems that arises in a flowshop environment where there are two processing
    stages and a single transporter that is available to deliver the finished jobs from the
    first stage to the second. There is a single machine in the first stage and two parallel
    machines in the second stage. The transporter can carry only one job in each
    shipment. Each job is first processed on the single machine at stage one, then
    transported to and processed on one of the two parallel machines at stage two. The
    objective is to minimize the makespan, i.e., the completion time of the last job in the
    second stage. Since this problem is strongly NP-hard, we propose a fast heuristic
    and show that the heuristic has a worst-case bound of 5/2. We also conduct
    numerical experiments to evaluate the average performance of this heuristic.