Operations Research, Systems Engineering and Industrial Engineering Commons^™

The Integration Of Wind Energy In The Electrical Grid During The Contingencies, Islam Ali

Dissertations and Theses @ UNI

As wind energy expansion develops, there are also many problems and challenges to connect the wind farms to the grid. There are many different interactions during the connection like the voltage flicker, harmonics, transient, short circuit current, frequency, and safety protection. Those problems may affect the performance of the grid and may cause serious problems. This study investigates the grid-connection problems for the wind turbines and offers appropriate solutions. This study provides a simulation for the power system during the faults. The electrical grid in the simulation contains generators and wind turbines which are connected to the grid. It also …

Robotic Manufacturing Cell: An Analysis Of Variables Affecting Performance, Elvis Alicic

Dissertations and Theses @ UNI

Analyzing the performance of manufacturing cells is a well established concept. The justification for conducting thorough analyses of manufacturing cells comes from the known advantages it can provide, including performance improvement and production planning improvement, both current and future. This study focuses on assessing the variables affecting performance of a robotic manufacturing cell through the measure of throughput. Initially, simulation modeling is utilized to model an existing robotic cell and compare the output to actual production output from the same cell. Additionally, general regression modeling is employed to analyze the following variables and their effect on throughput: machine downtime, off-plan …

An Investigation On In-Process Spc Sampling Frequency For Shaft Bearing Turning Process, Jiaxu Chu

Dissertations and Theses @ UNI

The machining processes have the uniqueness of discrete production and flexible scheduling as cellular manufacturing design. To ensure the quality of machining products, control charts for Statistical Process Control (SPC) has been implemented in the company to monitor the machining process. Sampling is an essential part of data collection for SPC control charts and sampling should be done for machining processes becomes an issue in the company.

This study focused on the investigation of SPC sampling frequencies for shaft bearing turning process using the technique of Average Production Length (APL). The purpose of the study was to identify the SPC …

Modeling And Analysis Of Grid-Connected Solar-Wind Hybrid Power System, Sultan Altamimi

Dissertations and Theses @ UNI

Renewable energies are considered to be a significant part of the energy mix to assist the existing electricity demand and the future of electrical generation. Electrical power simulation software is increasingly being used to answer and determine the source of potential problems in the actual power system. To have a better understanding of an electrical power system, it is essential to validate all the components through simulation within an environment that allows accurate modeling of all power system components. This research presents modeling and analysis of an actual grid-connected solar-wind hybrid system at University of Northern Iowa campus in Cedar …

The Design And Evaluation Of Wireless Sensor Networks For Applications In Industrial Locations, Hameed Madwar

Dissertations and Theses @ UNI

In manufacturing industries, there exist many applications where Wireless Sensor Networks (WSN's) are integrated to provide wireless solution for the automated manufacturing processes. It is well known that industrial environments characterized by extreme conditions such as high temperature, pressure, and electromagnetic (EM) interference that can affect the performance of the WSN's. The key solution to overcome this performance issue is by monitoring the received Signal Strength Index (RSSI) at the received sensor of the WSN device and track frame error rate of wireless packets.

ZigBee is a wireless sensor network (WSN) standard designed for specific needs of the remote monitoring …

Using Metarules To Integrate Knowledge In Knowledge Based Systems. An Application In The Woodworking Industry, Alvaro Villavicencio

Dissertations and Theses @ UNI

The current study addresses the integration of knowledge obtained from Data Mining structures and models into existing Knowledge Based solutions. It presents a technique adapted from common KADS and spiral methodology to develop an initial knowledge solution using a traditional approach for requirement analysis, knowledge acquisition, and implementation. After an initial prototype is created and verified, the solution is enhanced incorporating new knowledge obtained from Online Analytical Processing, specifically from Data Mining models and structures using meta rules. Every meta rule is also verified prior to being included in the selection and translation of rules into the Expert System notation. …

Adaptive Dynamic Programming For High-Dimensional, Multicollinear State Spaces, Bancha Ariyajunya

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Dynamic programming (DP) is a mathematical programming method for optimizing a system changing over time and has been used to solve multi-stage optimization problems in manufacturing systems, environmental engineering, and many other fields. Exact solutions are only possible for small problems or under very limiting restrictions, but computationally practical approximate DP methods now exist. Most continuous-state problems require discretization of the state space. A design and analysis of computer experiments (DACE) approach for approximate DP uses experimental design and statistical modeling to approximate the value function in continuous-state problems. However, ideal experimental designs are orthogonal, and when the state variables …

Cnt Reinforced Epoxy Foamed And Electrospun Nano-Fiber Interlayer Systems For Manufacturing Lighter And Stronger Featherweight Composites, Vasileios M. Drakonakis

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Multiple works have been performed in improving carbon fiber reinforced polymer (CFRP) composites especially in terms of strength so delamination, which is the major defect in laminated composites, is prevented. Nevertheless, there is not much focus on improving conventional CFRP systems in terms of weight especially when these are used in primary structures. This work questions whether lighter and at the same time stronger CFRP composites can be manufactured in order to replace conventional CFRP systems in major applications. Under this perspective, this study demonstrates that inducing controlled porosity may offer a systemic approach for manufacturing light weight carbon fiber …

Measurement And Analysis Of Vehicle Vibration For Delivering Packages In Small‐Sized And Medium‐Sized Trucks And Automobiles, Vanee Chonhenchob, Sher Paul Singh, Jay Jagjit Singh, Joseph Stallings, Gary Grewal

Industrial Technology and Packaging

In distribution, packaged products are subjected to the variation in vibration levels from transport vehicles that vary in frequency and acceleration while moving to their destinations. This vibration may negatively affect the product or packaging. This study measured and analysed vibration levels in vehicles commonly used to transport packages in the last leg of the package delivery service that is used by single‐parcel carriers. Using data recorders, we monitored vertical, lateral and longitudinal vibrations over 75 h of travel time in five different types of small and medium package delivery vehicles. The study presents these data as power density (PD) …

Extending Origami Technique To Fold Forming Of Sheet Metal Products, Ala Qattawi

All Dissertations

This dissertation presents a scientific based approach for the analysis of folded sheet metal products. Such analysis initializes the examination in terms of topological exploration using set of graph modeling and traversal algorithms. The geometrical validity and optimization are followed by utilizing boundary representation and overlapping detection during a geometrical analysis stage, in this phase the optimization metrics are established to evaluate the unfolded sheet metal design in terms of its manufacturability and cost parameters, such as nesting efficiency, total welding cost, bend lines orientation, and maximum part extent, which aides in handling purposes. The proposed approach evaluates the design …

Dock Assignment And Truck Scheduling Problems At Cross-Docking Terminals, Ching-Jung Ting, Amanda G. Rodríguez López

12th IMHRC Proceedings (Gardanne, France – 2012)

In this paper, we consider the integration of dock assignment and truck scheduling problem at cross-docking terminals. The problem is first formulated as a 0-1 integer programming model. Since both dock assignment and truck scheduling problems are NP-hard, its integration is more difficult to solve. Thus we propose reduced variable neighborhood search (RVNS) algorithms to solve the problem. Computational experiments are carried out on four set of instances. The results show that RVNS is capable of finding good solutions in a much shorter computation time when it is compared with optimization solver Gurobi’s solutions.

Investigation Into The Usability Of Micromechanical Models To Predict The Behavior Of A Nanocomposite Polymer, Jason Handlogten

All Graduate Theses, Dissertations, and Other Capstone Projects

The purpose of this thesis was to determine the acceptability of a set of existing nanocomposite test specimens for tensile testing and then to determine the Young's and shear modulus of these test specimens. If the test specimens were found to be acceptable, the accuracy of three micromechanical models was to be evaluated by comparing their predictions to the mechanical properties determined from testing the specimens. The set of existing nanocomposite test specimens had a distinct concave shape on two surfaces that were believed to be intended as flat. In order to determine if they adhered to the Type I …

Strategic Management And Entrepreneurship As Economic Development Tools, Norbert Ziemer

Doctoral Dissertations

This research develops a framework of Biobased Entrepreneurial Ventures for Rural Economic Development. Rural economic development poses unique challenges and opportunities, based on available production assets, workforce trends like "brain drain," and access to industry clusters. However, certain entrepreneurial venture opportunities are preferable for rural economic development. Since supply chains are vital to business success, initial emphasis is placed on the biomass resource base to be transformed through entrepreneurial activity into higher economic value outputs. The literature contains research on specific opportunities in rural economic development (e.g. ethanol, wind power). Many of these are limited in scope and depend on …

The Effects Of Personal Protective Respirators On Human Motor, Visual, And Cognitive Skills, Anas Ahmed Alghamri

Doctoral Dissertations

"In oxygen-deficient or toxic environments in which controlling the hazard is not feasible, workers wear personal protective respirators. Hazard controls include but are not limited to engineering controls, such as ventilation, and substituting less hazardous materials. However, respirator selection and the design of tasks that require respirators are critical issues. Understanding the effects of respirators on human abilities is critical to respirator selection and therefore to the safety and efficiency of workers. This research investigated the effect of respirators on human abilities. A review of the relevant literature was conducted, revealing that respirators can affect physiological, psychological, motor, and visual …

Dynamic Decision Making Under Uncertainty In Renewable Energy Portfolio Management And Inventory Management, Jianjun Deng

Doctoral Dissertations

"It is challenging and important for a firm to make effective decisions under uncertainties, such as random fluctuations of products prices or demands, etc. This dissertation formulates mathematic models to help decision makers in energy and retail industries make optimal timing and optimal operational decisions when facing uncertain electricity prices and demands. As for energy portfolio management, the optimal entry and dispatch strategies are investigated for an electricity generating firm to introduce a renewable power plant as an alternative method for generating electricity, with or without construction delay. In addition, the abandonment strategies of considering shutting down one of the …

A Socio-Technical Analysis Of Widespread Electric Vehicle Adoption, Onanwa Nneka Egbue

Doctoral Dissertations

A combination of high fuel costs, concerns about petroleum availability, and environmental issues associated with conventional vehicles powered by fossil fuels are driving interests in electric vehicles (EVs). Large-scale deployment of EVs can play a significant role in addressing some of these problems. In spite of the benefits of EVs, several obstacles need to be overcome before EVs will be widely adopted. This research focuses on two socio-technical issues that affect widespread adoption and sustainability of EVs, consumer attitudes and perceptions, and supply chain risks of raw materials for EV battery technology. A major barrier is that consumers tend to …

A Comparison Analysis Of Defensive Routines And Theories-In-Use Of Engineering And Non-Engineering Managers, Tyria Riley

Doctoral Dissertations

"Engineering managers are managers who have an understanding of both the technical and business world in organizations. Many lead teams of their peers who are purely technical individuals. However, the success of an engineering manager depends on being able to function in both worlds when necessary. There is a stigma that engineers experience challenges in areas such as communication, conflict resolution, and leadership. Due to these challenges, defensive routines are likely to exist. Defensive routines are behaviors that are common in many managers and may hinder the success of an organization. This research uses a case study approach to measure …

Modelling Interruptions Of Human-In-The Loop Tasks, Muhammet Servet Gulum

Doctoral Dissertations

"Interruptions are a part of our everyday experience and are increasingly becoming a part of our work. Systems are typically not designed with consideration of the effects of interrupting a user during a task sequence. Research is being done in the field of interruptions and its effects. There have been various claims about the effects of interruptions on human task performance. It has been shown that interruptions may not only increase the time to perform a task but also decrease the performance. It has also been analyzed that the effect of interruptions depends on many parameters including task complexity, point …

Analyses Of Alternative Energy Deployments, Mathew Thomas

Doctoral Dissertations

"Energy use around the world is rising drastically. Fossil fuels, including liquid fuels, natural gas, and coal, are expected to supply 80% of the world's energy need in 2035. As a result, the world's energy-related carbon dioxide emission is expected to increase from 30.2 billion metric tons in 2008 to 43.2 billion metric tons in 2035. Significant steps are necessary to reduce the dependence on fossil fuel and to reduce greenhouse gas emissions. Renewable and alternative energy technologies can assist in reducing the use of fossil fuels and can reduce greenhouse gas emissions. However, most of the renewable energy technologies …

Analyzing Risk And Catastrophic Accidents: Using Lopa And Human Factors To Improve Safety In Generic Projects, Siddharth B. Damle

Doctoral Dissertations

"Risk assessment and identification in the early stages of any project is critical to the success of that project from time, budget and cost prespective [sic]. Identifying unacceptable risks and making provisions to mitigate those, can reduce the uncertainty in the project and ensure its smooth completion and closure. Various techniques have been developed over time to identify and quantify risks. Inspite of all the available research on risk management tools, accidents continue to happen and projects consistently fail.

The objective of this study is to first, determine the generic risks that can be encountered by a project. A list …