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Full-Text Articles in Engineering

Grasp Based Metaheuristic To Solve The Mixed Fleet E-Waste Collection Route Planning Problem, Aldy Gunawan, Dang V.A. Nguyen, Pham K.M. Nguyen, Pieter. Vansteenwegen Aug 2023

Grasp Based Metaheuristic To Solve The Mixed Fleet E-Waste Collection Route Planning Problem, Aldy Gunawan, Dang V.A. Nguyen, Pham K.M. Nguyen, Pieter. Vansteenwegen

Research Collection School Of Computing and Information Systems

The digital economy has brought significant advancements in electronic devices, increasing convenience and comfort in people’s lives. However, this progress has also led to a shorter life cycle for these devices due to rapid advancements in hardware and software technology. As a result, e-waste collection and recycling have become vital for protecting the environment and people’s health. From the operations research perspective, the e-waste collection problem can be modeled as the Heterogeneous Vehicle Routing Problem with Multiple Time Windows (HVRP-MTW). This study proposes a metaheuristic based on the Greedy Randomized Adaptive Search Procedure complemented by Path Relinking (GRASP-PR) to solve …


A Grasp For Unitary Space-Time Codes, Adam Panagos, Kurt Louis Kosbar Nov 2005

A Grasp For Unitary Space-Time Codes, Adam Panagos, Kurt Louis Kosbar

Electrical and Computer Engineering Faculty Research & Creative Works

Unitary space-time codes perform well at high signal-to-noise ratios on MIMO channels even when the propagation coefficients between transmitter and receiver are unknown. One method of constructing unitary space-time constellations uses a random search to find signal constellations that minimize the maximum pairwise correlation between transmitted signals. The work presented here uses a greedy randomized adaptive search procedure (GRASP) for finding good unitary space-time code constellations. Simulation results show that, on average, this technique finds codes with better correlation properties than the random search method. This new search procedure was also used to find signal constellations with better correlation properties …