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Based on both white response and connotation expression are geometric progression in the most primitive grey differential equation of GM(1,1)x(0)(k)+ax(1)(k) = b, this paper begins with generation of the time response function's grey derivative at discrete points. Through derivative's definition, establishing a new GM(1,1) by optimizing grey derivative and background value. Then, getting the best coefficient c by introducing criterion function and it has proved that the new expression has the whitened exponent law coincident property and the whitened coefficient coincident property in theory. Finally, some examples show the new model has higher prediction precision. [ABSTRACT FROM AUTHOR]

This paper considers a stochastic variational inequality problem (SVIP). We first formulate SVIP as an optimization problem (ERM problem) that minimizes the expected residual of the so-called regularized gap function. Then, we focus on a SVIP subclass in which the function involved is assumed to be affine. We study the properties of the ERM problem and propose a quasi-Monte Carlo method for solving the problem. Comprehensive convergence analysis is included as well. [ABSTRACT FROM AUTHOR]

This paper presents a new verified optimization method for the problem of finding the densest packings of nonoverlapping equal circles in a square. In order to provide reliable numerical results, the developed algorithm is based on interval analysis. As one of the most efficient parts of the algorithm, an interval-based version of a previous elimination procedure is introduced. This method represents the remaining areas still of interest as polygons fully calculated in a reliable way. Currently the most promising strategy of finding optimal circle packing configurations is to partition the original problem into subproblems. Still, as a result of the highly increasing number of subproblems, earlier computer-aided methods were not able to solve problem instances where the number of circles was greater than 27. The present paper provides a carefully developed technique resolving this difficulty by eliminating large groups of subproblems together. As a demonstration of the capabilities of the new algorithm the problems of packing 28, 29, and 30 circles were solved within very tight tolerance values. Our verified procedure decreased the uncertainty in the location of the optimal packings by more than 700 orders of magnitude in all cases. [ABSTRACT FROM AUTHOR]

In this paper, a generalized fractional programming problem with linear constraints and the objective function is the sum of the functions of the form Minimize … Subject to the linear constraints Ax ≥ b, and x ≥ 0 where a'x+p , c'x + q and e'x + r are linear functions has been discussed. Solution of the above generalized fractional programming problem can be recovered by reducing it to a fractional programming problem. [ABSTRACT FROM AUTHOR]

A new type of public key cryptosystem, called MST3, has been recently introduced on the basis of covers and logarithmic signatures for non-abelian finite groups. The class of Suzuki 2-groups has been proposed for a possible realization of the generic scheme. Due to their simple structure, the groups enable us to study the security of the system and also provide an efficient implementation. An earlier relevant result of the cryptanalysis has shown that the transversal logarithmic signatures are unfit for use in this realization. In this paper we present a revised version of MST3 for the Suzuki 2-groups and show a thorough study of its security. Using heuristic and algebraic methods we establish strong lower bounds for the workload of conceivable direct attacks on the private key of the scheme. We then develop a powerful chosen plaintext attack which allows us to rule out the usage of a certain class of logarithmic signatures. In addition, we show a class of logarithmic signatures withstanding this attack and thus to our knowledge they could be used in the realization of the scheme. Finally, we describe and discuss the implementation issues of the scheme in detail and include data of its performance obtained from an experimental result. [ABSTRACT FROM AUTHOR]

In this paper, some necessary and sufficient optimality conditions for the weakly efficient solutions of vector optimization problems (VOP) with finite equality and inequality constraints are shown by using two kinds of constraints qualifications in terms of the MP subdifferential due to Ye. A partial calmness and a penalized problem for the (VOP) are introduced and then the equivalence between the weakly efficient solution of the (VOP) and the local minimum solution of its penalized problem is proved under the assumption of partial calmness. [ABSTRACT FROM AUTHOR]

This paper presents novel results on perfect reconstruction feedback quantizers (PRFQs), i.e., noise-shaping, predictive and sigma-delta A/D converters whose signal transfer function is unity. Our analysis of this class of converters is based upon an additive white noise model of quantization errors. Our key result is a formula that relates the minimum achievable MSE of such converters to the signal-to-noise ratio (SNR) of the scalar quantizer embedded in the feedback loop. This result allows us to obtain ana- lytical expressions that characterize the corresponding optimal filters. We also show that, for a fixed SNR of the scalar quantizer, the end-to-end MSE of an optimal PRFQ which uses the optimal filters (which for this case turn out to be HR) decreases exponentially with increasing oversampling ratio. Key departures from earlier work include the fact that fed back quantization noise is explicitly taken into account and that the order of the converter filters is not a priori restricted. [ABSTRACT FROM AUTHOR]

This paper presents methods of calculation of parameters of single-phase permanent-magnet (SPPM) motor, in terms of motor dimensions and material properties, which are utilized in the dynamic model of the motor. The intention of the study is to develop means of SPPM performance calculations, which lend themselves to be employed within a mathematical design optimization approach. The calculated parameters are compared with measured values and are shown to be accurate for the purpose of the study. [ABSTRACT FROM AUTHOR]

The issue of equivalence between chance-constrained programming problems (CCPP's) and Bayesian utility-maximization problems (BUMP's), and the anomalous evaluation of information in CCPP's, are re-examined in light of a recent paper by Jagannathan and the ensuing exchange between Jagannathan and LaValle. Difficulties in "explaining" value of information within the framework of chance-constrained programming are illustrated in a numerical example due to Jagannathan. [ABSTRACT FROM AUTHOR]

This paper concerns countable state space Markov decision processes endowed with a (long-run expected) average reward criterion. For these models we summarize and, in some cases, extend some recent results on sufficient conditions to establish the existence of optimal stationary policies. The topics considered are the following: (i) the new assumptions introduced by Sennott in [20–23], (ii) necessary and sufficient conditions for the existence of a bounded solution to the optimality equation, and (iii) equivalence of average optimality criteria. Some problems are posed. [ABSTRACT FROM AUTHOR]

This work presents an algorithm for multiobjective optimization that is structured as: (i) a descent direction is calculated, within the cone of descent and feasible directions, and (ii) a multiobjective line search is conducted over such direction, with a new multiobjective golden section segment partitioning scheme that directly finds line-constrained efficient points that dominate the current one. This multiobjective line search procedure exploits the structure of the line-constrained efficient set, presenting a faster compression rate of the search segment than single-objective golden section line search. The proposed multiobjective optimization algorithm converges to points that satisfy the Kuhn-Tucker first-order necessary conditions for efficiency (the Pareto-critical points). Numerical results on two antenna design problems support the conclusion that the proposed method can solve robustly difficult nonlinear multiobjective problems defined in terms of computationally expensive black-box objective functions. [ABSTRACT FROM AUTHOR]

In this paper a fault-detection (FD), filter-design method has been proposed for linear parameter-varying (LPV) systems. The FD filter is an optimal H∞ Luenberger observer synthesized by minimizing frequency conditions that ensure guaranteed levels of disturbance rejection and fault detection. Via the bounded real lemma (BRL) and the separation principle the design method is formulated as a convex linear matrix inequality (LMI) optimization problem. The resulting residual generator is parameter-dependent and uses the plant parameter assumed measurable online. Finally, an FD threshold logic is proposed in order to reduce the generation of false alarms. The effectiveness of the design technique is illustrated via a numerical example. [ABSTRACT FROM AUTHOR]

In this work, we investigate a combination of classical optimization techniques from optimal control and a rounding strategy based on shape optimization for interface identification for problems constrained by partial differential equations. The goal is to identify the location of pollution sources in a fluid flow represented by a control that is either active or inactive. We use a relaxation of the binary problem on a coarse grid as initial guess for the shape optimization with higher resolution. The result is a computationally cheap method, where large shape deformations do not have to be performed. We demonstrate that our algorithm is, moreover, able to change the topology of the initial guess. [ABSTRACT FROM AUTHOR]

This article presents a new multidimensional descent method for solving global optimization problems with box-constraints. This is a hybrid method where local search method is used for a local descent and global search is used for further multidimensional search on the subsets of intersection of cones generated by the local search method and the feasible region. The discrete gradient method is used for local search and the cutting angle method is used for global search. Two- and three-dimensional cones are used for the global search. Such an approach allows one, as a rule, to escape local minimizers which are not global ones. The proposed method is local optimization method with strong global search properties. We present results of numerical experiments using both smooth and non-smooth global optimization test problems. These results demonstrate that the proposed algorithm allows one to find a global or a near global minimizer. [ABSTRACT FROM AUTHOR]

Taking inspiration from the interacting process among organizations in human societies, this correspondence designs a kind of structured population and corresponding evolutionary operators to form a novel algorithm, Organizational Evolutionary Algorithm (OEA), for solving both unconstrained and constrained optimization problems. In OEA, a population consists of organizations, and an organization consists of individuals. All evolutionary operators are designed to simulate the interaction among organizations. In experiments, 15 unconstrained functions, 13 constrained functions, and 4 engineering design problems are used to validate the performance of OEA, and thorough comparisons are made between the OEA and the existing approaches. The results show that the OEA obtains good performances in both the solution quality and the computational cost. Moreover, for the constrained problems, the good performances are obtained by only incorporating two simple constraints handling techniques into the OEA. Furthermore, systematic analyses have been made on all parameters of the OEA. The results show that the OEA is quite robust and easy to use. [ABSTRACT FROM AUTHOR]

We propose a class of semidefinite programming (SDP) problems for which an optimal solution can be calculated directly, i.e., without using an iterative method. Several classes of such SDP problems have been proposed. Among them, Vanderbei and Yang (1995), Ohara (1998), and Wolkovicz (1996) are well known. We show that our class contains all of the three classes as special cases. [ABSTRACT FROM AUTHOR]