Business Commons^™

Full Disclosure: Model Uncertainty In Adjusting For Confounders, Dieudonne Dusenge

Graduate Theses and Dissertations

This study examines the role of knowledge about underlying causal relationships in classifying controls in order to mitigate omitted- and included-variable biases. Using simulations and accounting examples, the study shows that the researcher may not distinguish good and bad controls because the underlying causal relationships are unobservable, and remedying strategies (such as the relative timing of measurement) may not remove the uncertainty in the classification. Because of the uncertainty about which controls to use, two or more models will be credible as will the distinct estimates derived from them. Next, the study shows that the current standard practice of singling …

Greenhouse Tomatoes: Process Simulation, Juan Gabriel Marin Jr.

Graduate Theses and Dissertations

Growing population demand and challenges brought on by climate change have spurred the need for more resilient fruit and vegetable supply chains. One agricultural technology of significant interest is the use of greenhouses for food production. Greenhouses create a stable and adaptable environment for crops such as tomatoes to grow year-round. Fresh tomatoes are the second most consumed vegetable per capita in U.S. diets, currently averaging 20.7 pounds. The growing consumption of fresh tomatoes has been the result of increasing cultural diversity in the United States.

To meet the growing demand, Venlo-type greenhouses have been frequently used by growers. It …

Study On New Sampling Plans And Optimal Integration With Proactive Maintenance In Production Systems, Sinan Obaidat

Graduate Theses and Dissertations

Sampling plans are statistical process control (SPC) tools used mainly in production processes. They are employed to control processes by monitoring the quality of produced products and alerting for necessary adjustments or maintenance. Sampling is used when an undesirable change (shift) in a process is unobservable and needs time to discover. Basically, the shift occurs when an assignable cause affects the process. Wrong setups, defective raw materials, degraded components are examples of assignable causes. The assignable cause causes a variable (or attribute) quality characteristic to shift from the desired state to an undesired state.

The main concern of sampling is …

Simulation Modeling Of Cross-Dock And Distribution Center Based Supply Chains, Ghewa Al Chall

Graduate Theses and Dissertations

Companies are implementing new strategies to meet the customer requirements in terms of quality, timing, and cost. One of these strategies is cross-docking, which can be defined as the process of consolidating the products coming from different suppliers, but having the same destination, with minimal handling and almost no storage between loading and unloading of the goods. The purpose of this research is to investigate the benefits of having a cross-docking facility in a supply chain. In this research, we focus on developing discrete event simulation models using the opensource Java Simulation Library (JSL). Also, we work on augmenting an …

Classifying Interdependencies In The Food And Agriculture Critical Infrastructure Sector, John Doerpinghaus

Graduate Theses and Dissertations

This work classifies examples of infrastructure interdependencies found in the food and agriculture critical infrastructure sector. Interdependencies are identified through an examination of rice and poultry agriculture throughout the state of Arkansas. The subtleties of interdependence examples in the food and agriculture sector are inadequately captured by the well-studied interdependence classification taxonomies. Through 39 interviews, we develop an understanding of the subtle temporal, geographic, and productivity scales of interdependence in over 100 examples and present five new, distinct classifications of interdependence: (1) dynamic physical, (2) dynamic geographic, (3) deadline, (4) delay, and (5) human, economic, and natural resource interdependencies. An …

Decision Support System For Container Port Selection Using Multiple-Objective Decision Analysis, Rivelino De Icaza

Graduate Theses and Dissertations

Ports are essential for maritime transportation and global supply chains since they are nodes that connect the sea- and land-based modes of transportation. With containerization and supply chains stimulating global trade, ports are challenged to adjust to changes in the market to create value to their customers. Therefore, this dissertation research focuses on the container port selection decision analysis to provide information to help shipping lines select the best port for their shipping networks. Since the problem is complex, dynamic, and involves multiple and conflicting criteria, the research proposes to use the multi-objective decision analysis with Value-Focused Thinking approach. The …

Essays In Measuring, Controlling, And Coordinating Supply Chain Inventory And Transportation Operations, Payam Parsa

Graduate Theses and Dissertations

Supply chain collaboration programs, such as continuous replenishment program (CRP), is among the most popular supply chain management practices. CRP is an arrangement between two partners in a supply chain to share information on a regular basis for lowering logistics costs while maintaining or increasing service levels. CRP shifts the replenishment responsibility to the upstream partner to avoid the bullwhip effect across the supply chain. This dissertation aims to quantify, measure, and expand the benefits of CRP for the purpose of reducing logistics cost and improving customer service. The developed models in this dissertation are all applied in different case …

Personalized Decision Modeling For Intervention And Prevention Of Cancers, Fan Wang

Graduate Theses and Dissertations

Personalized medicine has been utilized in all stages of cancer care in recent years, including the prevention, diagnosis, treatment and follow-up. Since prevention and early intervention are particularly crucial in reducing cancer mortalities, personalizing the corresponding strategies and decisions so as to provide the most appropriate or optimal medical services for different patients can greatly improve the current cancer control practices. This dissertation research performs an in-depth exploration of personalized decision modeling of cancer intervention and prevention problems. We investigate the patient-specific screening and vaccination strategies for breast cancer and the cancers related to human papillomavirus (HPV), representatively. Three popular …

Is It We Or They? The Effect Of Identity On Collaboration And Performance In Buyer-Supplier Relationships, Siqi Ma

Graduate Theses and Dissertations

In today’s scale-driven and technology-intensive global economy, collaboration becomes the supply chain’s core capability (Liker and Choi, 2004). A well-developed ability to create and sustain fruitful collaborations gives companies a significant competitive advantage (Kanter, 1994). Retailers are increasingly relying on their suppliers to reduce costs, improve quality, and develop new processes and products faster than their rivals’ vendors can. On the other hand, suppliers benefit from retailers that they are able to monitor store-level demand in real time in order to ensure the top-selling items are in-stock or the accuracy and timeliness of retailer’s demand forecast. Previous literature has shown …

Using The Triple Bottom Line To Select Sustainable Suppliers For A Major Oil And Gas Company, Pandarinath Adarsh Sunkari

Graduate Theses and Dissertations

Companies have primarily been focusing on the financial bottom line i.e., on increasing profits by increasing revenues and reducing costs. With high energy usage and environmental change posing threats to the environment and business operations, companies are now considering sustainability. Since some global suppliers have low cost labor, Social well-being and human development has also emerged as major goals of a company performing global operations. Focusing on these three goals is termed the "Triple Bottom Line" (TBL). We study and explore the TBL benefits that could be realized by an oil and gas company by focusing on sustainable suppliers. A …

Inventory Management And Control "For A Cause", John Michael Miller

Graduate Theses and Dissertations

Companies today are changing the culture of business and beginning to involve more than just labor and money in overall decisions. Just as sustainability issues and humanitarian logistics are gaining popularity, so is the idea of using business to make a difference on society in addition to making a profit. As companies position themselves across the globe to make an impact, they employ people in third-world environments that create uncertainties on both the supply and demand sides. Also, the idea of strategically planning work with the goal of minimizing costs has been replaced by companies wanting to give more work …

Strategic Planning Tool Development Using Portfolio Decision Analysis, Luis B. Vargas Rojas

Graduate Theses and Dissertations

A portfolio decision analysis strategic planning tool was developed for the Facilities Management Office at the University of Arkansas. The tool provides information to support budget allocation decisions based on their Strategic Planning Project List, project attributes (e.g, seat utilization, scheduling preferences, and sustainability rank), and budget constraints. The projects are evaluated using multiobjective decision analysis. We introduce dynamic value functions, which vary the range of the value measures based on the planning horizon, to evaluate the projects). We determine facilities portfolios based on the project values and constraints using Linear Programming. In addition, insightful reports are generated, which provide …

Detailed Inventory Record Inaccuracy Analysis, Hayrettin Kaan Okyay

Graduate Theses and Dissertations

This dissertation performs a methodical analysis to understand the behavior of inventory record inaccuracy (IRI) when it is influenced by demand, supply and lead time uncertainty in both online and offline retail environment separately. Additionally, this study identifies the susceptibility of the inventory systems towards IRI due to conventional perfect data visibility assumptions. Two different alternatives for such methods are presented and analyzed; the IRI resistance and the error control methods. The discussed methods effectively countered various aspects of IRI; the IRI resistance method performs better on stock-out and lost sales, whereas error control method keeps lower inventory. Furthermore, this …

Time-Driven Activity-Based Costing For Healthcare Provider Supply Chain Processes, Martha Isaura Gonzalez

Graduate Theses and Dissertations

In a time when healthcare costs continue to rise, nearly a third of hospital operating expenses are related to supplies, and the healthcare supply chain is complex, it is pertinent for healthcare providers to have a clear understanding of their healthcare supply chain process costs. Having a clear picture into how these costs are driven and where opportunities for cost reductions exist can support supply chain efficiencies. In this research, we develop a Time-Driven Activity-Based Costing (TDABC) supply chain cost management tool for healthcare providers. A TDABC management system can provide healthcare providers with valuable product and process supply chain …

The Legitimation Of Novel Technologies: The Case Of Nanotechnology, Anastasia E. Thyroff

Graduate Theses and Dissertations

Nanotechnology is the control, manipulation, and application of matter on an atomic and molecular level. The technology is complex and confusing to consumers, and its long-term safety and effect on the human body, as well as the environment, are unknown. However, for the past decade, nanotechnology has been used to develop consumer products and food with novel and attractive attributes.

Since nanotechnology is still not well known, it is not legitimized; that is, it has not been deemed safe and accepted by society. However, the market for nanotechnology is in the legitimation process. It will take an entire network of …

Load Mixing To Improve Container Utilization, Crystal Wilson

Graduate Theses and Dissertations

The under utilization in trucking leads to nearly 5 billion gallons of wasted fuel annually. One way to recapture part of this waste is to use collaborative logistics. This research focuses on one specific aspect of collaborative logistics: load mixing. Load mixing is the idea of mixing two or more items of different weights in the same container to reduce the number of trucks needed.

Load mixing is similar to other packing problems such as the knapsack and container loading problems. However, traditional packing problems typically only assume a single type of capacity (e.g., weight), whereas load mixing must simultaneously …

An Empirical Investigation Of Supply Chain Excellence In Healthcare, Brian Keith Smith

Graduate Theses and Dissertations

This research is motivated by opportunities to improve the cost and quality of healthcare delivery through improved supply chain processes. This research assesses the quality of the healthcare supply chain and identifies factors that are driving supply chain excellence among organizations in the healthcare industry. The first objective of this research is to assess the state of quality measurement in the healthcare supply chain. The achievement of this first objective is presented in Chapter 3 of this dissertation in the form of a manuscript accepted for publication in The Quality Management Journal. The second research objective is to develop …