This paper presents and reviews the current application fields of mathematical programming in integrated iron- and steelmaking research. Three different fields of mathematical programming applications are identified a...
详细信息
This paper presents and reviews the current application fields of mathematical programming in integrated iron- and steelmaking research. Three different fields of mathematical programming applications are identified and discussed: unit operation optimization, by-product gas distribution, and integrated system optimization and design. Based on current research activities in the iron and steel industry, development trends for mathematical programming in integrated iron- and steelmaking research, such as the cogeneration of chemicals aided by renewable energy grid integration, are presented.
In the paper we compare the performance of seven important multivariate and mathematical programming methods in the multigroup classification problem with simulated data. Our approach extends previous results from two...
详细信息
In the paper we compare the performance of seven important multivariate and mathematical programming methods in the multigroup classification problem with simulated data. Our approach extends previous results from two to multiple groups and recognizes simultaneously different types of classification errors in a multivariate analysis of variance (MANOVA) framework. (C) 1998 Elsevier Science B.V.
In this work, a fully automated, step-by-step, 1st order matrix force method is developed for the analysis of planar (2D) and spatial (3D) structural frames made of elastic-hardening plastic material. Plasticity (idea...
详细信息
In this work, a fully automated, step-by-step, 1st order matrix force method is developed for the analysis of planar (2D) and spatial (3D) structural frames made of elastic-hardening plastic material. Plasticity (ideal and hardening) is modelled using plastic hinges of zero-length. The proposed automation techniques utilize Lagrange multipliers to model all forms of discontinuities in a simple and efficient way, within the framework of mathematical programming: internal discontinuities (e.g. articulations) as well as element eccentricities are taken into account. The problem may be solved using any quadratic/non-linear optimization algorithm with linear constraints;the redundant forces/moments serve as the primary unknowns. A load-controlled numerical strategy that is suitable for any predefined loading scenario analysis is proposed;its efficiency is demonstrated via a set of examples which are compared with existing results from the literature or output from commercial software based on the equivalent direct stiffness method. (C) 2018 Elsevier Ltd. All rights reserved.
This paper presents an algorithm for solving large-scale polynomial (nonlinear) zero-one programming problems. The procedure incorporates a mixture of pseudo-Boolean concepts and time-proven implicit enumeration proce...
详细信息
This paper presents an algorithm for solving large-scale polynomial (nonlinear) zero-one programming problems. The procedure incorporates a mixture of pseudo-Boolean concepts and time-proven implicit enumeration procedures. Significant savings in the time required to obtain optimal solutions results from the use of a minimum cover to analyze the future effect of a particular implicit enumeration iteration. Additional improvement is obtained through the use of a term ranking strategy to control the arborization of the implicit enumeration process. Computational experience demonstrates that this algorithm can reduce the magnitude of the computer solution time for large problems from several minutes to a matter of a few seconds.
Flexible Process Planning (FPP) is one of the key intelligent manufacturing techniques. The FPP problem is exactly and concisely formulated using 0-1 mathematical programming. Compared with the existing models, the ne...
详细信息
Flexible Process Planning (FPP) is one of the key intelligent manufacturing techniques. The FPP problem is exactly and concisely formulated using 0-1 mathematical programming. Compared with the existing models, the new formulation simultaneously considers alternative operation selection and sequencing and operational method assignment under two optimization criteria. The new formulation does not need to plot the common AND/OR-network that often depicts partial possible processing routes. Distinctively, the important operational precedence constraint is beforehand transformed into the possible successor set of each operation and the possible immediate successor set. Three methods are creatively proposed to prohibit from generating a cycle in sequencing. The complicated criteria involving the machine, tool and setup changeover identification are linearly expressed. The experimental results indicate that the proposed 0-1 linear programming models are able to quickly obtain the optimal solution of the small-scale problems and stably find a satisfactory solution of the large-scale problems within acceptable time. Compared with the existing mathematical programming models for process planning, the proposed linear models have lower complexity and better performance in solving benchmark instances. In two groups of comparative experiments, the number of constraints of the proposed linear models dramatically reduces by 99.6% and 70%, respectively. Moreover, all benchmark instances are exactly solved by the Cplex solver using the proposed linear models within one hour.& COPY;2022 Elsevier B.V. All rights reserved.
The triangular norm-based operations in fuzzy logic usually lead to non-L-R type fuzzy sets. This study considers mathematical programming problems with non-L-R type fuzzy parameters. It shows that the fuzzy solutions...
详细信息
The triangular norm-based operations in fuzzy logic usually lead to non-L-R type fuzzy sets. This study considers mathematical programming problems with non-L-R type fuzzy parameters. It shows that the fuzzy solutions to such problems can be obtained by solving an optimization problem on a mixed domain. The necessary and sufficient conditions for solving the resulting optimization problems are investigated by employing the theory of convex optimization on mixed domains. This is the first attempt to solve the fuzzy optimization problem with non-L-R type membership functions in view of optimization problems on a mixed domain.
A model using integer quadratic mathematical programming has been developed to control the inbreeding level (or genetic diversity) through group coancestry in a selection programme for a forestry population structured...
详细信息
A model using integer quadratic mathematical programming has been developed to control the inbreeding level (or genetic diversity) through group coancestry in a selection programme for a forestry population structured in terms of maternal families coming from different locations. A method to calculate the average group coancestry between- and within-families for these open-pollinated populations is also proposed. This model has been applied to data from a breeding programme of Australian Eucalyptus globus. The strategy proved to be effective as reductions of up to 50% for the group coancestry of the selected individuals were reached with a loss of only 5% of the maximum attainable selection differential (corresponding to truncation selection).
In recent years, research has identified the spatial spreading of freight distribution patterns as one of the largest drivers of the rapid growth in freight transport ton-miles, and of related growth in overall energy...
详细信息
In recent years, research has identified the spatial spreading of freight distribution patterns as one of the largest drivers of the rapid growth in freight transport ton-miles, and of related growth in overall energy use and other forms of environmental impact. In this paper, prospects for long-term redistribution of freight flows are explored using origin-destination (OD) flow data from the 1993 US Commodity Flow Survey and a minimum-error technique for estimating disaggregate commodity flows. A prototype analysis of the pulp and paper sector was carried out. The analysis found that matching demand for paper products with geographically optimal production centers and producing an optimal mix of outputs in each center could lead to substantial reductions in total ton-miles (on the order of 17-38%) compared to the 1993 base case. A conceptual example of the implementation of the methodology and an analysis of potential energy savings from spatial redistribution are also presented. (C) 2001 Elsevier Science B.V. All rights reserved.
The primary aim of process-network synthesis, or PNS in short, is to determine the best process network achieving a desired goal, e.g., producing a set of desired products or satisfy demands. PNS has a long history, a...
详细信息
The primary aim of process-network synthesis, or PNS in short, is to determine the best process network achieving a desired goal, e.g., producing a set of desired products or satisfy demands. PNS has a long history, and numerous methods for executing it are available. Its acceleratedly increasing importance can be attributed to the need to respond to the rapid emergence of new technologies and fast changes in the economic environment. It is highly desirable that any corporation be able to ascertain if a new technology is viable for its business as well as to assess if its current technology remains sustainable in the changing environment. Herein, a novel method and software for PNS are proposed for generating, optimizing, and analyzing alternative process designs at the conceptual level. The method is illustrated by synthesizing alternative process designs with different network structures for the production of butanol, ethanol, and acetone from grains. Furthermore, the sustainability of the resultant process designs is analyzed. This is executed by varying the payout period and the production rate, i.e., load.
The contact condition is described as a linear complementarity form with penalty parameters. Based on the boundary element discretization, a mathematical programming method for elastic contact problems with friction i...
详细信息
The contact condition is described as a linear complementarity form with penalty parameters. Based on the boundary element discretization, a mathematical programming method for elastic contact problems with friction is presented. This method avoids the tiresome iterative procedures used in previous work and, if there is no unloading, only one incremental step is necessary for a solution. Two examples are given to demonstrate the correctness and effectiveness of the method.
暂无评论