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Biogeography-Based Optimization For Combinatorial Problems And Complex Systems, Dawei Du
Biogeography-Based Optimization For Combinatorial Problems And Complex Systems, Dawei Du
ETD Archive
Biogeography-based optimization (BBO) is a heuristic evolutionary algorithm that has shown good performance on many problems. In this dissertation, three problem1s 1 are researched for BBO: convergence speed and optimal solution convergence of BBO,1 1BBO application to combinatorial problems, and BBO application to complex systems. The first problem is to analyze BBO from two perspectives: how the components of BBO affect its convergence speed and the reason that BBO converges to the optimal solution. For the first perspective, which is convergence speed, we analyze the two essential components of BBO -- population construction and information sharing. For the second perspective, …
Oppositional Biogeography-Based Optimization, Mehmet Ergezer
Oppositional Biogeography-Based Optimization, Mehmet Ergezer
ETD Archive
This dissertation outlines a novel variation of biogeography-based optimization (BBO), which is an evolutionary algorithm (EA) developed for global optimization. The new algorithm employs opposition-based learning (OBL) alongside BBO migration to create oppositional BBO (OB BO). Additionally, a new opposition method named quasi-reflection is introduced. Quasireflection is based on opposite numbers theory and we mathematically prove that it has the highest expected probability of being closer to the problem solution among all OBL methods that we explore. Performance of quasi-opposition is validated by mathematical analysis for a single-dimensional problem and by simulations for higher dimensions. Experiments are performed on benchmark …
External Control Interface, Dynamic Modeling And Parameter Estimation Of A Research Treadmill, Omer Sirin
External Control Interface, Dynamic Modeling And Parameter Estimation Of A Research Treadmill, Omer Sirin
ETD Archive
Treadmills providing linear continuous movement are used for robotic testing of prostheses in order to study their operating characteristics. However, traditional exercise treadmills are not able to simulate various conditions such as avoiding an obstacle, climbing, descending, reversing direction, or stopping instantly. The focus of this thesis is to examine control algorithms (position, speed and force) for the drive mechanism of a research treadmill to fulll the gap in the situations described above. The system consists of a power supply, a computer with Matlab, and the treadmill that includes a DC motor, a pulley and belt. Also, an external encoder …
Distributed Biogeography Based Optimization For Mobile Robots, Arpit Shah
Distributed Biogeography Based Optimization For Mobile Robots, Arpit Shah
ETD Archive
I present hardware testing of an evolutionary algorithm (EA) known as distributed biogeography based optimization (DBBO). DBBO is an extended version of biogeography based optimization (BBO). Typically, EAs require a central computer to control the evaluation of candidate solutions to some optimization problem, and to control the sharing of information between those candidate solutions. DBBO, however, does not require a centralized unit to control individuals. Individuals independently run the EA and find a solution to a given optimization problem. Both BBO and DBBO are based on the theory of biogeography, which describes how organisms are distributed geographically in nature. I …