Results 41 to 50 of about 95,488 (287)
Advanced Science, EarlyView.A meta‐YAG crystal with artificially order/disorder structures was fabricated to realize the efficient third‐harmonic generation at 343 nm with a conversion efficiency of 4.5×10−3, surpassing six orders of magnitude compared to bulk YAG crystal. Moreover, a wide spectral tunability from 331 to 356 nm was also achieved in the meta‐YAG, indicating its ...
Xiaotian Guo +6 more
wiley +1 more source
EURO Journal on Computational Optimization, 2015 We present O(n2)an integer linear formulation that uses the so-called “distance variables” to solve the quadratic assignment problem (QAP). The formulation performs particularly well for problems with Manhattan distance matrices.
Serigne Gueye, Philippe Michelon
doaj +1 more source
Conformal Reconfigurable Intelligent Surfaces: A Cylindrical Geometry Perspective
Advanced Electronic Materials, EarlyView.Cylindrical reconfigurable intelligent surfaces are explored for low‐complexity beam steering using one‐bit meta‐atoms. A multi‐level modeling approach, including optimization‐based synthesis, demonstrates that even minimal hardware can support directive scattering.
Filippo Pepe +4 more
wiley +1 more source
Solution Methods for the Dynamic Generalized Quadratic Assignment Problem
MathematicsIn this paper, the generalized quadratic assignment problem (GQAP) is extended to consider multiple time periods and is called the dynamic GQAP (DGQAP).
Yugesh Dhungel, Alan McKendall
doaj +1 more source
From combinatorial optimization to real algebraic geometry and back
Croatian Operational Research Review, 2014 In this paper, we explain the relations between combinatorial optimization and real algebraic geometry with a special focus to the quadratic assignment problem.
Janez Povh
doaj +1 more source
Applied Economic Perspectives and Policy, EarlyView.ABSTRACT The present study uses an agroeconomic supply model to assess the impacts of 2023–2027 CAP on Italian specialized dairy cattle farms. The model considers the voluntary choice of Eco‐Scheme 1, specifically addressed to livestock farms, through the implementation of binary variables.
Davide Dell'Unto, Raffaele Cortignani
wiley +1 more source
Food Tastes in the United States: Convergence or Divergence?
Agribusiness, EarlyView.ABSTRACT This study investigates how food consumption tastes have changed in recent decades across the United States. Using NielsenIQ data for over 77 million transactions, there is evidence of divergence in food tastes across regions from 2007 to 2016 and across households of different income, education, and race/ethnicity groups.
Michael DeDad
wiley +1 more source
Semidefinite Programming Approach for the Quadratic Assignment Problem with a Sparse Graph
, 2017 The matching problem between two adjacency matrices can be formulated as the NP-hard quadratic assignment problem (QAP). Previous work on semidefinite programming (SDP) relaxations to the QAP have produced solutions that are often tight in practice, but ...
Ferreira, Jose F. S. Bravo +2 more
core +1 more source
Trust‐region filter algorithms utilizing Hessian information for gray‐box optimization
AIChE Journal, EarlyView.Abstract Optimizing industrial processes often involves gray‐box models that couple algebraic glass‐box equations with black‐box components lacking analytic derivatives. Such systems challenge derivative‐based solvers. The classical trust‐region filter (TRF) algorithm provides a robust framework but requires extensive parameter tuning and numerous ...
Gul Hameed +4 more
wiley +1 more source
Exploiting Group Symmetry in Semidefinite Programming Relaxations of the Quadratic Assignment Problem [PDF]
We consider semidefinite programming relaxations of the quadratic assignment problem, and show how to exploit group symmetry in the problem data. Thus we are able to compute the best known lower bounds for several instances of quadratic assignment ...
Klerk, E. de, Sotirov, R.
core +4 more sources