Digital Commons Network^™

Optimization Models And Algorithms For Demand Response In Smart Grid., Guangyang Xu

Electronic Theses and Dissertations

For demand response in smart grid, a utility company wants to minimize total electricity cost and end users want to maximize their own utility. The latter is considered to consist of two parts in this research: electricity cost and convenience/comfort. We first develop a system optimal (SO) model and a user equilibrium (UE) model for the utility company and end users, respectively and compare the difference of the two. We consider users' possible preference on convenience over cost-saving under the real-time pricing in smart grid, and each user is assumed to have a preferred time window for using a particular …

Order Picking Strategies For Healthcare Warehouses., Ehsan Khodabandeh

Electronic Theses and Dissertations

Order picking is the process of collecting goods and items in specified quantities from storage locations, in response to customer orders. Since many labor resources are involved in this process, finding ways to make it more efficient have been a primary goal for researchers and practitioners. Determining a better allocation of products to the storage areas, finding the best route and sequence to pick multiple products, and choosing the best picking policies to minimize congestion in the aisles are just a few of many objectives regarding order picking process. Due to regulatory compliances and the chance of product spoilage, additional …

The Robust Urban Transportation Network Design Problem, Alireza Naimi

Electronic Theses and Dissertations

In today’s congested transportation networks, disruptions like crashes may cause unexpected and significant delays. All transportation networks are vulnerable to disruptions, to some extent, with temporary or permanent effects. Vulnerability is more important in urban transportation networks, due to heavy use and road segments that are close to each other. Small disturbances on an urban transportation network segment can have a huge impact on its accessibility. Intelligent adversaries may take advantage of these vulnerable parts of the network and disrupt transportation operations, increasing the overall transportation cost for the users.Often, the decision about improving the networks in transportation planning and …

Mathematical Modeling And Optimization Of Three-Echelon Capacitated Supply Chain Network Design, Sahand Ashtab

Electronic Theses and Dissertations

This dissertation is concerned with mathematical modeling and optimization of three-echelon capacitated supply chain network design (SCND) with suppliers, distribution centers (DCs) and customer zones. An introduction to SCND is provided followed by a literature review. Being inspired by a real world SCND problem, a Mixed Integer Linear Program (MILP) is developed for a three-echelon SCND. The model takes into account the operational costs of a built DC based on its actual activity level rather than the assumption that a built DC operates at the maximum capacity. The suppliers and customer zones are at fixed known locations and the DCs …

Optimizing Vehicle Usage Using Csp, Sat And Max-Sat, Raheem T. Al Rammahi

Electronic Theses and Dissertations

Most of the companies in Iraq spend significant amounts of time and money when transferring employees between home and work. In this thesis, we model the problem of the Dhi Qar Oil company (DQOC) transportations using three modeling languages from AI: Constraint Programing (CP), Boolean Satisfiability (SAT), and Maximum Satisfiability (MAX-SAT). We then use solvers to find optimal solutions to this problem.

We show which of these solvers is more efficient when finding optimal solutions. For this purpose, we create a test suite of 360 problems to test these solvers. All solvers are applied to these problems and the final …

Economic Analysis Of A Data Center Virtual Power Plant Participating In Demand Response, Labi Bajracharya

Electronic Theses and Dissertations

Data centers consume a significant amount of energy from the grid, and the number of data centers are increasing at a high rate. As the amount of demand on the transmission system increases, network congestion reduces the economic efficiency of the grid and begins to risk failure. Data centers have underutilized energy resources, such as backup generators and battery storage, which can be used for demand response (DR) to benefit both the electric power system and the data center. Therefore, data center energy resources, including renewable energy, are aggregated and controlled using an energy management system (EMS) to operate as …

Linear-Phase Fir Digital Filter ‎Design With Reduced Hardware Complexity Using Discrete Differential Evolution, Muhammed Kunwar Rehan

Electronic Theses and Dissertations

Optimal design of xed coe cient nite word length linear phase FIR digital lters for custom ICs has been the focus of research in the past decade. With the ever increasing demands for high throughput and low power circuits, the need to design lters with reduced hardware complexity has become more crucial. Multiplierless lters provide substantial saving in hardware by using a shift add network to generate the lter coe cients. In this thesis, the multiplierless lter design problem is modeled as combinatorial optimization problem and is solved using a discrete Di erential Evolution algorithm. The Di erential Evolution algorithm's …

Energy-Efficient Spectrum Sensing Approaches For Cognitive Radio Systems, Faroq Ali Awin

Electronic Theses and Dissertations

Designing an energy efficient cooperative spectrum sensing for cognitive radio network is our main research objective in this dissertation. Two different approaches are employed to achieve the goal, clustering and minimizing the number of participating cognitive radio users in the cooperative process. First, using clustering technique, a multilevel hierarchical cluster-based structure spectrum sensing algorithm has been proposed to tackle the balance between cooperation gain and cost by combining two different fusion rules and exploiting the tree structure of the cluster. The algorithm considerably minimizes the reporting overhead while satisfying the detection requirements. Second, based on reducing the number of participating …