Operations Research, Systems Engineering and Industrial Engineering Commons^™

Lean Thinking For Lead-Time Reduction And Efficient Knowledge Creation In Product Development, Satish Kumar Tyagi

Wayne State University Dissertations

There are many distinct differences between manufacturing process and Product Development (PD) process, so lean tools have to be customized to deliver results in the later domain. The main focus of this dissertation is to extend them to manage and improve the PD process in order to develop the product faster while improving or at least maintaining the level of performance and quality. For aforesaid purpose, value stream mapping (VSM) method is used to explore the wastes, inefficiencies, non-valued added steps in a single, definable process out of complete PD process. Besides numerous intangible benefits, VSM framework will help the …

Modeling And Optimization Of Non-Profit Hospital Call Centers With Service Blending, Yanli Zhao

Wayne State University Dissertations

This dissertation focuses on the operations problems in non-profit hospital call centers with inbound and outbound calls service blending.

First, the routing policy for inbound and outbound calls is considered. The objective is to improve the system utilization under constraints of service quality and operators' quantity. A collection of practical staffing assignment methods, separating and mixing staffing policy are evaluated. Erlang C queuing model is used to decide the minimum number of operators required by inbound calls. Theoretical analysis and numerical experiments illustrate that through dynamically assigning the inbound and outbound calls to operators under optimal threshold policy, mixing staffing …

Reliability Analysis And Optimal Maintenance Planning For Repairable Multi-Component Systems Subject To Dependent Competing Risks, Nailong Zhang

Wayne State University Dissertations

Modern engineering systems generally consist of multiple components that interact in a complex manner. Reliability analysis of multi-component repairable systems plays a critical role for system safety and cost reduction. Establishing reliability models and scheduling optimal maintenance plans for multi-component repairable systems, however, is still a big challenge when considering the dependency of component failures. Existing models commonly make prior assumptions, without statistical verification, as to whether different component failures are independent or not. In this dissertation, data-driven systematic methodologies to characterize component failure dependency of complex systems are proposed. In CHAPTER 2, a parametric reliability model is proposed to …

A Prediction Modeling Framework For Noisy Welding Quality Data, Junheung Park

Wayne State University Dissertations

Numerous and various research projects have been conducted to utilize historical manufacturing process data in product design. These manufacturing process data often contain data inconsistencies, and it causes challenges in extracting useful information from the data. In resistance spot welding (RSW), data inconsistency is a well-known issue. In general, such inconsistent data are treated as noise data and removed from the original dataset before conducting analyses or constructing prediction models. This may not be desirable for every design and manufacturing applications since every data can contain important information to further explain the process. In this research, we propose a prediction …

Formal Design Concept And Participant Behavior Analysis For Crowdsourcing Design, Jihoon Kim

Wayne State University Dissertations

Crowdsourcing has emerged as a new design resource for conceptual design process and multiple crowdsourcing services provide an opportunity for design idea collection and concept generation by crowds. However, few formal methods are available to extract and evaluate design concepts from the activities of the design crowd. Scarcity of information and non-guaranteed quality of contributions are often challenges to be tackled. To overcome the challenges, the research aims to answer how a system systematically extracts and represents the explicit or implicit hidden design concepts from crowdsourcing design activities and how crowdsourcing design activities of participants are captured as design information …

Frontiers In Operations Research For Overcoming Barriers To Vehicle Electrification, Mahyar Movahed Nejad

Wayne State University Dissertations

Electric vehicles (EVs) hold many promises including diversification of the transportation energy feedstock and reduction of greenhouse gas and other emissions. However, achieving large-scale adoption of EVs presents a number of challenges resulting from a current lack of supporting infrastructure and difficulties in overcoming technological barriers. This dissertation addresses some of these challenges by contributing to the advancement of theories in the areas of network optimization and mechanism design.

To increase the electric driving range of plug-in hybrid electric vehicles (PHEVs), we propose a powertrain energy management control system that exploits energy efficiency dif- ferences of the electric machine and …

Improving Emergency Department Patient Flow Through Near Real-Time Analytics, Shanshan Qiu

Wayne State University Dissertations

ABSTRACT

IMPROVING EMERGENCY DEPARTMENT PATIENT FLOW THROUGH NEAR REAL-TIME ANALYTICS

This dissertation research investigates opportunities for developing effective decision support models that exploit near real-time (NRT) information to enhance the "operational intelligence" within hospital Emergency Departments (ED). Approaching from a systems engineering perspective, the study proposes a novel decision support framework for streamlining ED patient flow that employs machine learning, statistical and operations research methods to facilitate its operationalization.

ED crowding has become the subject of significant public and academic attention, and it is known to cause a number of adverse outcomes to the patients, ED staff as well as …

An Analytics Approach To Designing Patient Centered Medical Home, Saeede Ajorlou

Wayne State University Dissertations

Recently the patient centered medical home (PCMH) model has become a popular team based approach focused on delivering more streamlined care to patients. In current practices of medical homes, a clinical based prediction frame is recommended because it can help match the portfolio capacity of PCMH teams with the actual load generated by a set of patients. Without such balances in clinical supply and demand, issues such as excessive under and over utilization of physicians, long waiting time for receiving the appropriate treatment, and non continuity of care will eliminate many advantages of the medical home strategy. In this research, …

An Analytics Approach To Reducing Hospital Readmission, Issac Shams

Wayne State University Dissertations

One of the significant sources of waste in the Unites States health care systems is preventable hospital readmission. About 2.3 million Medicare fee-for-service beneficiaries are re-hospitalized within 30 days after discharge which incurs an annual cost of $17 billion. However, it is reported by the Medicare Payment Advisory Commission that about 75% of such readmissions can and should be avoided because they are the results of factors such as poor planning for follow up care transitions, inadequate communication of discharge instructions, and failure to reconcile and coordinate medications. Hence, reducing unnecessary rehospitalization through care transition and systems engineering principles has …

Global E-Mentoring: Overcoming Virtual Distance For An Effective Mentoring Relationship, Nancy Philippart

Wayne State University Dissertations

Mentoring can enhance an employee's career development and advancement but traditional face-to-face mentoring has become less relevant because of globalization, increased employee mobility and technology-enabled work. A new mentoring model enabled by technology has emerged to meet the needs of today's complex, fast changing global workplace. Although e-mentoring has several advantages over traditional mentoring, the absence of regular face-to-face interactions requires different strategies to develop an effective mentoring relationship. Moreover, additional complexities arise when this virtual mentoring is global.

This research utilizes the construct of virtual distance, the "psychological separation" that has been found to impact performance outcomes of geographically …

Demand Modeling And Capacity Planning For Innovative Short Life-Cycle Products, Saman Alaniazar

Wayne State University Dissertations

This dissertation focuses on demand modeling and capacity planning for innovative short life-cycle products. We first developed a new model in the class of stochastic Bass formulations that addresses the shortcomings of models from the extant literature. The proposed model considers the common fact that the market potential of a product is not fixed and might change during a life-cycle due to exogenous (e.g., economic- or competitors-related) or endogenous (e.g., quality-related) factors. Allowing this parameter (market potential in the Bass model) to follow a geometric random walk, we have showed that the future demand of a product in each period …

Exact And Representative Algorithms For Multi Objective Optimization, Ozgu Turgut

Wayne State University Dissertations

In most real-life problems, the decision alternatives are evaluated with multiple conflicting criteria. The entire set of non-dominated solutions for practical problems is impossible to obtain with reasonable computational effort. Decision maker generally needs only a representative set of solutions from the actual Pareto front. First algorithm we present is for efficiently generating a well dispersed non-dominated solution set representative of the Pareto front which can be used for general multi objective optimization problem. The algorithm first partitions the criteria space into grids to generate reference points and then searches for non-dominated solutions in each grid. This grid-based search utilizes …

Optimization Of Strategic Planning Processes For Configurable Products: Considerations For Global Supply, Demand, And Sustainability Issues, Edward Lawrence Umpfenbach

Wayne State University Dissertations

The assortment planning problem is to decide on the set of products that a retailer or manufacturer will offer to its customers to maximize profitability. While assortment planning research has been expanding in recent years, the current models are inadequate for the needs of a configurable product manufacturer. In particular, we address assortment planning for an automobile manufacturer. We develop models to integrate assortment planning and supply chain management, designed for use by a large automaker in its strategic planning phase. Our model utilizes a multinomial logit model transformed into a mixed integer linear program through the Charnes-Cooper transformation. It …

Engineering Problem Solving And Sustained Learning: A Mixed Methods Study To Explore The Dynamics Of Engineering Knowledge Creation, Rachel Itabashi-Campbell

Wayne State University Dissertations

This dissertation research explores processes by which engineering problem solving (EPS) results in sustained organizational learning. Approaching from a constructionist perspective, the study empirically examines the knowledge creation dynamics instigated by product-related problems using a mixed methods research approach. The research has identified the Japanese concept of ba, defined in this study as "shared experiential space," as a key construct that explains the phenomena of interest. A new framework that the study has developed, which interprets EPS as an epistemic journey to attain system-wide improvements, is highly complementary to the traditional structured routine based approaches to engineering operations and …

An Integrated Framework For Freight Forwarders:Exploitation Of Dynamic Information For Multimodal Transportation, Farshid Azadian

Wayne State University Dissertations

Advent of real-time information broadcasting technologies, growth in demand for air-cargo, and increased congestion and variability on air-road network, are the main forces compelling today's air-freight forwarders to improve their operational decision-making to be more competitive and responsive to needs of customers. This research studies the air-cargo transportation on both road (short-haul) and air (long haul) network from the perspective of a mid-size freight forwarder.

We develop a routing algorithm for congestion avoidance on air-network based on historical data and introduce an innovative approach to incorporate real-time information to enable dynamic routing of cargo on a stochastic air-network. In the …

Sampling Based Progressive Hedging Algorithms For Stochastic Programming Problems, Nezir Aydin

Wayne State University Dissertations

Many real-world optimization problems have parameter uncertainty. For instances where the uncertainties can be estimated to a certain degree, stochastic programming (SP) methodologies are used to identify robust plans. Despite advances in SP, it is still a challenge to solve real world stochastic programming problems, in part due to the exponentially increasing number of scenarios. For two-stage and multi-stage problems, the number of scenarios increases exponentially with the number of uncertain parameters, and for multi-stage problems also with the number of decision stages.

In the case of large scale mixed integer stochastic problem instances, there are usually two common approaches: …

Decision Support Models For The External Variety Of Configurable Products, Erkan Isikli

Wayne State University Dissertations

The decision of what configurations of a product to offer is a difficult one for marketing and sales departments. In this study, we developed decision support models that can help decision makers when using operational models to manage external variety of configurable products. Our main objective is to reduce the number of product variants offered in a proper way so that inventory and demand models do not suffer from the curse of dimension. Due to its ability and flexibility, our framework can be employed under various marketing actions. We applied our framework to both qualitative and quantitative data.

An Integrated Framework For Configurable Product Assortment Planning, Seyed Ali Taghavi Behbahani

Wayne State University Dissertations

A manufacturer's assortment is the set of products or product configurations that the company builds and offers to its customers. While the literature on assortment planning is growing in recent years, it is primarily aimed at non-durable retail and grocery products. In this study, we develop an integrated framework for strategic assortment planning of configurable products, with a focus on the highly complex automotive industry. The facts that automobiles are highly configurable (with the number of buildable configurations running into thousands, tens of thousands, and even millions) with relatively low sales volumes and the stock-out rates at individual dealerships (even …

A Framework For Personalized Dynamic Cross-Selling In E-Commerce Retailing, Arun K. Timalsina

Wayne State University Dissertations

Cross-selling and product bundling are prevalent strategies in the retail sector. Instead of static bundling offers, i.e. giving the same offer to everyone, personalized dynamic cross-selling generates targeted bundle offers and can help maximize revenues and profits. In resolving the two basic problems of dynamic cross-selling, which involves selecting the right complementary products and optimizing the discount, the issue of computational complexity becomes central as the customer base and length of the product list grows. Traditional recommender systems are built upon simple collaborative filtering techniques, which exploit the informational cues gained from users in the form of product ratings and …

Throughput Analysis And Bottleneck Management Of Production Lines, Hatice Ucar

Wayne State University Dissertations

Companies are increasing their manufacturing excellence in order to stay competitive in the globalizing market. Plants are becoming more complex year by year due to increasing product classes, hardware complexity, etc... The design and operation of manufacturing systems is of greater importance today than it was in the past. Many studies have been carried out on the design and operation of manufacturing systems by academicians and practitioners over the years, however, there is still no agreement on how to best predict and improve the factory performance (Gershwin, 2000). The studies are based on either analytical approaches or simulation-based approaches. Success …

Development Of A Computer-Aided Design Supporting System For Transformative Product Design, Keunho Choi

Wayne State University Dissertations

Modern product innovation is often delivered by fusing technologies from different domains. To meet the current speedy pressure of product innovation, the conceptual design is a very critical stage to develop an innovative product. This research presents a new design paradigm, Transformative Product Design (TPD), to meet the demands in the conceptual design. TPD aims to design a new product from a combination out of a base product and reference products, which have been developed.

To expedite the TPD paradigm, Interaction Network is introduced to represent a product design by following a representative product design representation method in the teleological …

Rfid-Based Business Process And Workflow Management In Healthcare:Design And Implementation, Xiaoyu Ma

Wayne State University Dissertations

The healthcare system in the United States is considered one of the most complex systems and has encountered challenges related to patient safety concerns, escalating costs, and unpredictable outcomes. Many of these problems share a common cause - a lack of efficient business process management and visibility into the real-time location, status, and condition of medical resources. The goal of this research is to propose a newly integrated system to model, automate, and monitor healthcare business processes using an automatic data collection technology to record the timing and location of activities and identify their various resources.

This dissertation makes several …

Self Learning Strategies For Experimental Design And Response Surface Optimization, Adel Alaeddini

Wayne State University Dissertations

Most preset RSM designs offer ease of implementation and good performance over a wide range of process and design optimization applications. These designs often lack the ability to adapt the design based on the characteristics of application and experimental space so as to reduce the number of experiments necessary. Hence, they are not cost effective for applications where the cost of experimentation is high or when the experimentation resources are limited. In this dissertation, we present a number of self-learning strategies for optimization of different types of response surfaces for industrial experiments with noise, high experimentation cost, and requiring high …

Novel Models And Algorithms For Systems Reliability Modeling And Optimization, Dingzhou Cao

Wayne State University Dissertations

Recent growth in the scale and complexity of products and technologies in the defense and other industries is challenging product development, realization, and sustainment costs. Uncontrolled costs and routine budget overruns are causing all parties involved to seek lean product development processes and treatment of reliability, availability, and maintainability of the system as a true "design parameter". To this effect, accurate estimation and management of the system reliability of a design during the "earliest stages" of new product development is not only critical for managing product development and manufacturing costs but also to control life cycle costs (LCC). In this …

An Integrated Decision Support Framework For Remanufacturing In The Automotive Industry, Akhilesh Kumar

Wayne State University Dissertations

In today's global economy, firms are seeking any and every opportunity to differentiate from competitors by reducing supply chain costs and adding value to end customers. One increasingly popular option, under growing consumer awareness and increasing legislation, is to reintegrate returned products into the supply chain to achieve economic benefits as well as improve sustainability. An important class of such "reverse" goods flows has to do with remanufacturing (reman), which refers to activities that restore returned products ("cores") or their major modules to operational condition for using in place of new product or distributing through other channels (e.g., spare parts). …

Dynamic Routing On Stochastic Time-Dependent Networks Using Real-Time Information, Ali R. Guner

Wayne State University Dissertations

In just-in-time (JIT) manufacturing environments, on-time delivery is one of the key performance measures for dispatching and routing of freight vehicles. Both the travel time delay and its variability impact the efficiency of JIT logistics operations, that are becoming more and more common in many industries, and in particular, the automotive industry. In this dissertation, we first propose a framework for dynamic routing of a single vehicle on a stochastic time dependent transportation network using real-time information from Intelligent Transportation Systems (ITS). Then, we consider milk-run deliveries with several pickup and delivery destinations subject to time windows under same network …

Hazard Rate Models For Early Warranty Issue Detection Using Upstream Supply Chain Information, Chongwen Zhou

Wayne State University Dissertations

This research presents a statistical methodology to construct an early automotive warranty issue detection model based on upstream supply chain information. This is contrary to extant methods that are mostly reactive and only rely on data available from the OEMs (original equipment manufacturers). For any upstream supply chain information with direct history from warranty claims, the research proposes hazard rate models to link upstream supply chain information as explanatory covariates for early detection of warranty issues. For any upstream supply chain information without direct warranty claims history, we introduce Bayesian hazard rate models to account for uncertainties of the explanatory …

Causal Product Knowledge Management, Yun Seon Kim

Wayne State University Dissertations

The US engineering industry base is facing a significant loss of knowledge due to large numbers of employees retiring in the next decade. Problems in various product developments including product design may arise when the expertise is no longer available or the knowledge is forgotten. Also, most of product design knowledge is not reusable, because product design knowledge in an organization remains un-codified. Generally, knowledge-based system can solve or infer these problems. However, knowledge-based systems have been developed solely through the use of rule-based approach, which allows for easy modeling of expert reasoning, but such an approach is not general …

Task Analysis, Modeling, And Automatic Identification Of Elemental Tasks In Robot-Assisted Laparoscopic Surgery, Lavie Pinchas Golenberg

Wayne State University Dissertations

Robotic microsurgery provides many advantages for surgical operations, including tremor filtration, an increase in dexterity, and smaller incisions. There is a growing need for a task analyses on robotic laparoscopic operations to understand better the tasks involved in robotic microsurgery cases. A few research groups have conducted task observations to help systems automatically identify surgeon skill based on task execution. Their gesture analyses, however, lacked depth and their class libraries were composed of ambiguous groupings of gestures that did not share contextual similarities.

A Hierarchical Task Analysis was performed on a four-throw suturing task using a robotic microsurgical platform. Three …