We consider matching markets at a senior level, where workers are assigned to firms at an unstable matching-the status-quo-which might not be Pareto efficient. It might also be that none of the matchings Pareto superi...
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We consider matching markets at a senior level, where workers are assigned to firms at an unstable matching-the status-quo-which might not be Pareto efficient. It might also be that none of the matchings Pareto superior to the status-quo are Core stable. We propose two weakenings of Core stability: status-quo stability and weakened stability, and the respective mechanisms which lead any status-quo to matchings meeting the stability requirements above mentioned. The first one is inspired by the Top trading cycle and Deferred Acceptance procedures, the other one belongs to the family of branch and bound algorithms. The last procedure finds a core stable matching in many-to-one markets whenever it exists, dispensing with the assumption of substitutability.
An addition chain for a natural number n is a sequence 1 = a(0) < a(1) < ....< a(r) = n of minimal length of an addition chain for n is denoted by l(n). If j=i-1, then step is called a star step. We show that...
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An addition chain for a natural number n is a sequence 1 = a(0) < a(1) < ....< a(r) = n of minimal length of an addition chain for n is denoted by l(n). If j=i-1, then step is called a star step. We show that there is a minimal length addition chain for n such that the last four steps are stars. Then we conjecture that there is a minimal length addition chain for n such that the last [l(n)/2]-steps are stars. We verify that the conjecture is true for all numbers up to 2(18). An application of the result and the conjecture to generate a minimal length addition chain reduce the average CPU time by 23-29% and 38-58% respectively, and memory storage by 16-18% and 26-45% respectively for m-bit numbers with 14 <= m <= 22.
Mixed-model assembly line is utilised to assemble many product variants on a single line in automobile and other industries. In just-in-time production system, the automation (Jidoka) allows workers to stop a conveyor...
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Mixed-model assembly line is utilised to assemble many product variants on a single line in automobile and other industries. In just-in-time production system, the automation (Jidoka) allows workers to stop a conveyor line whenever they fail to complete their assembly operations within predetermined process times. Given this situation, it becomes important to determine the production sequence to minimise the total conveyor stoppage time in the mixed-model assembly line. In this article, we propose an explicit and complete formulation of the production sequencing problem for the mixed-model line, in which the objective function is to minimise the total line stoppage time. Some important properties are derived and by relaxing the integer constraints in the formulation, a branch and bound algorithm is developed. The performance of a commercial mathematical programming package is discussed by solving several numerical examples using the formulation.
This paper describes an exact algorithm for the optimal cyclic scheduling in a robotic cell with flexible processing times and a material handling robot. The problem is formulated with the prohibited intervals of the ...
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ISBN:
(纸本)9781424426294
This paper describes an exact algorithm for the optimal cyclic scheduling in a robotic cell with flexible processing times and a material handling robot. The problem is formulated with the prohibited intervals of the cycle time based on the capacity constraints of the machines and the robot. After the analysis of the developed mathematic model, the problem is transformed to enumerate the non-prohibited intervals for the cycle time. An efficient branch and bound algorithm is proposed to complete this enumeration procedure. Computational results on randomly generated test instances indicate that the algorithm is effective.
Nash Equilibrium is the solution of the Cournot Model considering the reaction functions provided that outputs are successive. However in practice, the outputs of some products are not successive. An improved branch a...
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ISBN:
(纸本)9780769535609
Nash Equilibrium is the solution of the Cournot Model considering the reaction functions provided that outputs are successive. However in practice, the outputs of some products are not successive. An improved branch and bound algorithm is proposed combining the Nash Equilibrium, considering the discontinuous output. The proposed algorithm is different from the traditional algorithm where the respond functions would be converted into constrains. While the improved algorithm is used to calculate the output of each manufacturer, the worst solution arising in the mid-process of calculation will be removed firstly, and then the final common integer solution of all manufactures will be the optimal solution. The procedure of the proposed algorithm is explicated in this paper. An example where two manufactures exist is studied, and the results validate the effectiveness of the method.
An instruction word in VLIW (very long instruction word) processors consists of a variable number of individual instructions. Therefore the power consumption variation over time significantly depends on the parallel i...
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ISBN:
(纸本)0780387368
An instruction word in VLIW (very long instruction word) processors consists of a variable number of individual instructions. Therefore the power consumption variation over time significantly depends on the parallel instruction schedule generated by the compiler. Sharp power variations across time cause power supply noises, degrade chip reliability and accelerate battery exhaustion. This paper proposes a branch and bound algorithm for instruction scheduling of VLIW architectures that effectively minimizing power v ariation without degrading the speed. Our experimental results demonstrate the efficiency of our algorithm compared with previously presented approaches. Finally, a new rough sets based approach to the instruction-level VLIW power model for this instruction scheduling optimization problem is discussed.
The present work is proposed to establish a comparative study between the exact method, namely, the algorithmbranch and bound, in respect of the artificial intelligence approaches (the genetic algorithms as well as t...
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ISBN:
(纸本)9780986041983
The present work is proposed to establish a comparative study between the exact method, namely, the algorithmbranch and bound, in respect of the artificial intelligence approaches (the genetic algorithms as well as the neural ones). The purpose is to highlight the artificial intelligence noticeable performance in solving the multi- product and multi- period model through the above-mentioned method, with the aim of providing a solution for the reverse logistics' site-localization problem regarding end-of-life products. For the sake of reaching, a solution within a reasonable tune, however, the genetic algorithm and neural network have displayed a remarkable ability to effectively solve the problem, as considered in relation to the assessment and sorting or separation procedure (branch and bound algorithm), constructed within a CPLEX shopping solver. In addition, a comparative study between the three methods is going to be established.
Many New Space initiatives run on new micro-launchers delivering a set of satellites on their specific targeted orbits. It opens the question of designing a sequence ordering the orbit visits, including initial and fi...
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ISBN:
(数字)9781624107115
ISBN:
(纸本)9781624107115
Many New Space initiatives run on new micro-launchers delivering a set of satellites on their specific targeted orbits. It opens the question of designing a sequence ordering the orbit visits, including initial and final orbits constrained respectively by launcher performance and end-of-life requirements. An optimization problem is defined, consisting in minimizing the propellant consumption (which is restricted by the upper stage propellant loading), under orbit constraints. The parameters are the orbit visit order, and associated maneuver characteristics. A specific method handling this Mixed Integer Non Linear Programming problem, its implementation and validation are described, including a micro-launcher representative study case.
Conventional image steganography is assumed to transmit the message, in the most securest way possible for a given payload, over lossless channels, and the associated steganographic schemes are generally vulnerable to...
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ISBN:
(纸本)9798400701085
Conventional image steganography is assumed to transmit the message, in the most securest way possible for a given payload, over lossless channels, and the associated steganographic schemes are generally vulnerable to active attacks, e.g., JPEG re-compression, and scaling, as seen on social networks. Although considerable progress has been made on robust steganography against JPEG re-compression, there exist few steganographic schemes capable of resisting scaling attacks due to the tricky inverse interpolations involved in algorithm design. To tackle this issue, a framework for robust image steganography resisting scaling with general interpolations either in std form with fixed interpolation block, or prefiltering-based anti-aliasing implementation with variable block, is proposed in this paper. And the task of robust steganography can be formulated as one of constrained integer programming aiming at perfectly recovering the secret message from the stego image while minimizing the difference between cover and stego images and the embedding distortion between scaled cover and scaled stego images. By introducing a metric - the degree of pixel involvement (dPI) to identify the modifiable pixels in the cover image, the optimization problem above could be effectively solved using the branch and bound algorithm (B&B). Extensive experiments demonstrate that the proposed scheme could not only resist scaling attacks with various interpolation techniques at arbitrary scaling factors (SFs), but also outperform the prior art in terms of security between the cover and stego images by a clear margin. In addition, the application of the proposed method in LinkedIn against the joint attacks of scaling and JPEG re-compression also shows its effectiveness on social network in real-world scenarios.
Consolidation and processing of the experts' knowledge in the correction of communication and social skills of students with autism spectrum disorder seem to be both an actual task, and a challenge. Being well-awa...
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Consolidation and processing of the experts' knowledge in the correction of communication and social skills of students with autism spectrum disorder seem to be both an actual task, and a challenge. Being well-aware of special needs of each and every student, psychologists and medics, as well as all the participants of education of ASD students, when making a decision about which information technology to use, apply their experience with exact ASD student. Expert evaluation technique enables support in such decision making, and its result can be used as input information to optimization task, solving which will allow taking into account different constraints.
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