Engineering Commons^™

On The Design For Flexibility Of Manufacturing Systems : A Stochiastic Approach, Nathapol Areeratchakul

Dissertations

Flexibility has emerged as one of the most strategic imperatives for company viability in today's fast paced economy. This realization has stimulated extensive research efforts in this area most of which have focused mainly on defining flexibility and its attributes, the need for flexibility and how to measure it. Nevertheless, despite the considerable amount of publications regarding flexibility and its related subjects, insufficient attention has been given to the optimality of the design for flexibility and the inherent needs to meet uncertainty. Bridging this gap is the intent of this work.

In this dissertation, developed analytical models are for the …

A Multi-Factor Model For Evaluating Manufacturing Defect Opportunities In Six Sigma Analysis, Karthikeyan Sundaram

Theses

Six Sigma Quality Analysis provides a structured method for manufacturing quality problems and defect opportunities to be defined, measured, analyzed, improved, and controlled. The technique is now being widely used in both the manufacturing and service industries to evaluate the classical "defects per million" metric. An underlying assumption of classical Six Sigma Analysis is that all defects contribute equally to the derivation of the defect rate. In the thesis, it is proposed that this assumption skews and often distorts the derived defect rate. Using classical Six Sigma the user is able to list a large number of often border-line defect …

Investigating Graphical User Interface Usability On Task Sequence And Display Structure Dependencies, Tirthankar Sengupta

Dissertations

Designing Graphical User Interfaces (GUI) requires the consideration of task sequence requirements (sequence of operations arising from task structures and application constraints) and display structure (layout of the elements of the interface) relationships. The basic purpose was to understand the usability differences of the interfaces through efficiency, motor performance, and search performance.

Thirty-two subjects performed experiments in four groups. The experiments differed in display structure and compatibility of task sequences. Subject mouse actions, mouse coordinates and eye positions were recorded. The derived measures, click efficiency, mouse traversal and eye visits to different areas of interest (namely the tool, object, and …

Human Factors Approach Towards Improving Readability Of Bus Schedules, Anand Tharanathan

Theses

Due to an increasing concern over the readability of existing bus schedules of a public transportation agency the schedule format was redesigned. Two prototype schedules were designed based on the gathered information from the literature survey, focus group meetings and data from other public transportation agencies' schedules. One of the prototypes was designed by giving primary importance to the direction of travel and was named the directional prototype schedule. The other prototype was designed by giving primary importance to the day of the week, and was named weekday / weekend prototype schedule. A time based laboratory experiment and a subjective …

Case Studies In Disassembly Process Planning, Riteshkumar Dhimmar

Theses

The rapid advancement in technology started in last century and still continuing resulted in decreased life cycle of electronic products. It also resulted in increased product disposal rate and filling land fill space faster causing shortage of such space and consequently creates major environmental problems. So, since couple of decade environmental concern has focused on production process and environmental regulations imposed by government has watched industrial pollution. With government regulations to control environmental problems; consumers are also aware of adverse effects of product disposal forcing manufacturer to become more responsible for safe product disposal and recycling of used product.

A …

Supply Chain Risk Analysis, Venkata R. Kallepalli

Theses

A new decision support system is proposed and developed that will help sustaining business in a high-risk business environment. The system is developed as a web application to better integrate the supply chain entities and to provide a common platform for performing risk analysis in a supply chain. The system performs a risk analysis and calculates risk factor with each activity in the supply considering its interrelationship with other activities. Bayesian networks along with fault tree structures are embedded in the system and logical rules are used to perform a qualitative fault tree analysis, as the data required to calculate …

Supply Chain Risk Mitigation, Roshan R. Pai

Theses

In recent years, especially post 9/11, there has been an increasing awareness for securing business supply chains against probable disruptions. With globalization and lean inventories, the efficiency of supply chain has greatly enhanced over the years, but at the expense of new vulnerabilities. Supply chain vulnerabilities have resulted in disruptions to the economic stability and security. As a result, risk analysis and mitigation has now grown to become one of the key links to business stabilization. To ensure business continuity, it is necessary to identify key assets (physical and operational) within the supply chain and secure them against probable threats. …

Simulation Analysis Of Anti-Rollover Mechanism For Vehicles, Mohib L. Raid

Theses

Rollover accidents are considered the most significant safety problems for all classes of light vehicles, especially pickups, Sport Utility Vehicles (SUV), Light Truck Vehicle (LTV) and vans. The main objective of the research is the design of a new mechanism able to keep the vehicle stable under various road conditions and high speeds, to prevent the vehicle from rolling over and to maintain the stability for the vehicle by creating an anti-rolling torque on the vehicle body capable of turning the vehicle smoothly to stable position.

Modeling And Analysis Of Hospital Facility Layout Problem, Amol Shrikrishna Padgaonkar

Theses

The optimal solution to any facility layout problem is an important aspect and a major concem as it involves significant material handling and transportation cost. The objective is to arrange the departments within the predefined facility boundaries in the way that the interaction between the functions is efficient and the overall movement cost is minimized. While facility layout problems have traditionally focused on manufacturing facilities, there has been little work on analyzing layouts for hospitals. The thesis focuses on hospital facility layout problems (HLP) to (i) minimize the movements of patients and (ii) minimize the movements of accompanying resources such …

Integrating Tolerances In G And M Codes Using Neural Networks, Vijay Kumar Sundareshan

Theses

Continuous integrated solutions from CAD down to the preparation of NC programs were developed in the recent years. However, if tolerances should be considered, the interaction of human experts is still necessary. A way to fill this gap in the production process is shown in this thesis. The study builds a relationship between the given design tolerances and including these tolerances in machining by generating respective G and M codes. The study focuses on physical phenomena and their inter-relationship while manufacturing. For example how the speed of machining, torque, power, depth of cut, etc. influences machining under specified tolerances. Artificial …

Analysis Of Costs And Delivery Intervals For Multiple-Release Software, High-Way Sun

Dissertations

Project managers of large software projects, and particularly those associated with Internet Business-to-Business (B2B) or Business-to-Customer (B2C) applications, are under pressure to capture market share by delivering reliable software with cost and timing constraints. An earlier delivery time may help the E-commerce software capture a larger market share. However, early delivery sometimes means lower quality. In addition, most of the time the scale of the software is so large that incremental multiple releases are warranted.

A Multiple-Release methodology has been developed to optimize the most efficient and effective delivery intervals of the various releases of software products, taking into consideration …

A Conceptual Framework Of Cost/Benefit Justification For Ergonomic Projects To Reduce Musculoskeletal Disorders In The Workplace, Nitipong Boon-Long

Dissertations

A framework for justifying ergonomic projects to the overall cost savings is developed which estimates the extent of musculoskeletal disorders (MSDs) exposures to a specific industry. A cost structure is developed to estimate the investment needed for an ergonomics program and the costs related to MSDs problems including workers' compensation costs, work-related costs, and labor turnover costs. Data was adopted from sources including Bureau of Labor Statistics (BLS), the Healthcare Cost and Utilization Project (HCUP-3), and estimates suggested in OSHA's former Ergonomics Standard. Top fifteen manufacturing industries with the highest MSDs rates were selected to apply the framework. Results showed …

Designing Web-Based Adaptive Learning Environment : Distils As An Example, Lilian Cao

Dissertations

In this study, two components are developed for the Web-based adaptive learning: an online Intelligent Tutoring Tool (ITT) and an Adaptive Lecture Guidance (ALG). The ITT provides students timely problem-solving help in a dynamic Web environment. The ALG prevents students from being disoriented when a new domain is presented using Web technology. A prototype, Distributed Intelligent Learning System (DISTILS), has been implemented in a general chemistry laboratory domain.

In DISTILS, students interact with the ITT through a Web browser. When a student selects a problem, the problem is formatted and displayed in the user interface for the student to solve. …

Simulation Modeling For Integrated E-Supply Chain Management, Pornsarun Wirojanagud

Theses

E-supply chain management is an emerging area of interest as companies begin to explore the Internet's potential to restructure supply chain relationships. The environmental impact of e-supply chain management is a critical issue towards sustainability. This thesis discusses and models an integrated e-supply chain network accounting for material and information flows throughout the supply chain in order to analyze the environmental implications and tradeoffis with other system characteristics. The network structure has complex interactions between various entities. In order to understand and analyze dynamic performance, a discrete-event simulation approach is utilized. An integrated tool was developed using the Arena simulation …

A Novel Approach Towards Usability Studies For Visual Search Tasks In Graphical User Interface Applications Using The Activity Theory Approach, Tirthankar Sengupta

Theses

The field of Human Computer Interaction still strives for a generalized model of visual search tasks (icon search, menu search, text search, label search, search through hypertext and feature recognition). The existing models of visual search, in spite of being impressive, are limited under certain perspectives due to lack of generality. The thesis tries to provide a holistic approach for the modeling of visual search tasks in graphical user interfaces from the Activity Theory (AT) perspective with the aim of rendering a theoretical bridge between HCI and Psychology. A detailed review of literature from the variegated discipline contributing to the …

Empirical Model-Based Control For End Milling Process, Abdelmalak Salib

Dissertations

The main objective of this research is to develop an empirical model-based control mechanism to maintain a fine surface finish quality by maintaining on-line cutting force values. The proposed model has been developed to present the control model constraints, by varying the machining parameters to control the force output to be constant. To relate the surface finish and the cutting force in the end milling machining process, a design of experiment has been conducted to determine the effect of two different materials (aluminium and steel) and the machining parameters (feed rate, spindle speed) at a predefined depth of cut.

Regression …

Development And Integration Of A Decision Support System For Electronic Outsourcing Into Telemanufacturing Service Provider, Vikram Batra

Theses

The use of computers and Information Technology enables manufacturers, especially small and medium size enterprises (SMEs) to improve productivity and increase manufactuning flexibility. Telemanufactuning or manufacturing in virtual environment is one of the infrastructures that facilitate the use of information superhighways and computer technology to attain these goals. Broadly defined, Telemanufactuning is the utilization of services accessed via communication networks and across information superhighways to perform in real time, operations and processes essential to the design and production of items. It can be a key enabler for decentralized manufacturing using global resources and expert design teams. In addition to updating …

Optimum Design And Machining Parameters Of A Permanent Magnet Brushless Dc Linear Motor As A Cnc Feed Drive, William Tereshkovich

Dissertations

A new heuristic has been developed to determine optimal operating parameters applied to a permanent magnet brushless DC linear motor (PMBDCLM) as a CNC feed drive. An FEA model has been developed utilizing an -electromagnetic postprocessor to provide performance output of a PMBDCLM and DC servomotor. Based on the developed FEA models, velocity results have been utilized to provide feedrate levels for design of experiments (DOE). DOE has been conducted to provide force, tolerance, and surface finish data necessary for the performance comparison of a DC servo motor/ballscrew equipped CNC vertical milling machine and a PMBDCLM equipped CNC vertical milling …

Assessing The Impact Of Design For Environment Guidelines : A Case Study Of Office Telephones, Hussam Fawzi Al-Okush

Theses

This research addresses a fundamental question: How much of the improvement in a product's environmental performance is directly attributable to the Design for Environment (DFE) tools and guidelines, and how much results simply from other design objectives or enabling technologies? The research examines four generations of a business telephone over the last thirty years, including the current generation, which has been designed using DEE guidelines. A lifecycle assessment (LCA) and demanufacturing analysis were performed on each of the first three generations to determine various technology and non-DEE trends. This information was used to forecast the progression to a 1997 non-DEE …

Metrics For Estimating The Product Disassembly Effort, Pradeep Kumar Yedlarajaiah

Theses

The concepts of environmentally friendly manufacturing and ecological reuse of materials have resulted in an increase in the number of disposed products that are disassembled. Moreover, the imposition of EPA regulations is forcing companies to invest in methods for protecting the environrnent. The first strategy in this vein is material recycling. The issue of recycling became important because of the limited landfill space, diminishing natural resources, environmental pollution due to dumping of products containing hazardous materials. Likewise, it is projected that the cost of extracting materials from natural resources is going to be much more expensive when compared to reclaiming …

A Study To Analyze And Improve Mechanical And Electro-Mechanical Designs Using Design For Quality Manufacturability (Dfqm) Technique, Bhavani P. Veerapaneni

Theses

The competitive nature of modern manufacturing demands that an innovative approach be used to build advanced and robust designs. Shortening the product development time, which is the period from initial design to full production, is a priority to most manufacturers today. Design for Quality Manufacturability (DFQM) is a methodology to address manufacturing / assembly quality issues during product design. As a consequence DFQM helps shorten the product development time.

The DFQM methodology addresses the issue of quality manufacturability (QM) - the likely hood that defects will occur during the manufacture of a product in a standard plant. The DFQM architecture …

A Decision Support System For The Equipment Selection Of Robotic Manufacturing Cells, Lars Johan Resare

Theses

Considering the principles of concurrent engineering, a Decision Support System (DSS) is developed to aid in the equipment selection of robotic manufacturing cells. The objective is to synchronously and simultaneously select proper equipment for the cell to provide efficient performance, subject to operational and budgetary constraints.

The DSS consists of several modules, including a data base that houses the specifications of equipment available in the market place, a first cut selection module, and an optimization engine. In its development, the optimization scheme utilizes analytical models and algorithms that capture different sources of variability in production, such as tolerances, clearances and …

Scheduling In Assembly Type Job-Shops, Nutthapol Asadathorn

Dissertations

Assembly type job-shop scheduling is a generalization of the job-shop scheduling problem to include assembly operations. In the assembly type job-shops scheduling problem, there are n jobs which are to be processed on in workstations and each job has a due date. Each job visits one or more workstations in a predetermined route. The primary difference between this new problem and the classical job-shop problem is that two or more jobs can merge to foul' a new job at a specified workstation, that is job convergence is permitted. This feature cannot be modeled by existing job-shop techniques. In this dissertation, …

Design Improvement Using Reverse Analysis In Design For Quality Manufacturability, Vikram V. Datla

Theses

The competitive needs of modern manufacturing demands that innovative approaches be used to gain an edge over the competitors. least Product design is one of the key dimensions wazzu in which companies can excel. Shortening the product design cycle so as to rapidly launch defect free products, is the goal of most companies. Design for Quality Manufacturability (DFQM) is a technique used to evaluate the quality manufacturability of a product at the design stage, so as to eliminate quality problems during production.

DFQM provides a means for relating the activities of quality improvement, product design and manufacturability analysis. The basis …

Analysis Of Surface Texture Parameters And Cutting Forces In Milling Operations, Preetesh U. Munshi

Theses

It has been known and understood that milling is quite a complicated process being a multi-point cutting tool operation. Each Surface texture is complex and requires different functions of forces to get the optimized Surface Texture. The challenge faced here is to devise any form of relation between the Surface Texture and the Milling Operating parameters (Spindle Speed, Feed rate, Depth of Cut), Cutting forces and the Milling Operating parameters and also between the Surface Texture and the Cutting Forces.

This Research study was conducted to determine the effect of the Operating Parameters on Surface Texture and Cutting forces and …

Measuring The Need For Manufacturing Flexibility And Evaluating Its Economic Benefits, Navin Karwande

Theses

Flexible systems are known of enabling organizations to take advantage of diversified products, low volume production items with short life-cycles. They also improve the ability to respond to market changes. Flexibility has thus become a strategic manufacturing need in recent years.

Because of the high initial capital outlay involved, the selection of the appropriate flexible solution has become a critical issue. This thesis proposes a methodology to determine the most cost effective and feasible flexibility strategy. A flexibility audit is developed to analyze and evaluate the changes taking place in a facility's environment. These changes and a measurement scheme is …

Effects Of Ergonomic Worksite Changes On Risks For Cumulative Trauma Disorders Of The Upper Body In An Assembly And Press Operation Job, David B. Mahone

Theses

Cumulative trauma of the upper body is associated with a variety of individual and job factors. An effort to optimize the human-hardware interface to minimize cumulative trauma is favored. Workers in a set of jobs had complained about hand/wrist and shoulder discomfort. One job was selected for testing alternate machine controls and worksite layout. Electromyography was used to test muscle activity, and photogoniometry was used to measure posture.

For the group of ten worker-subjects, statistically significant decreases in hand/wrist and shoulder muscle activity were found. A marginal, but significant increase in neck muscle activity was also found. When one subject …

Analysis Of A Design For Its Quality Manufacturability In Terms Of Misalignments And Fastener Related Problems, Abhinav Dhar

Theses

This study analyzes the relationship between design parameters established at the initial stage of the design process and the manufacturing quality problems that manifest themselves during production. Specifically, we study the relationship between design features and the occurrence of misalignment defects and fastener related problems.

This outcome of this work is a methodology, Design for Quality Manufacturability (DFQM). DFQM addresses the likelihood that defects will occur during the manufacture of a product in a standard plant. This is based on the premise that defects in assembled products are often influenced by some features of the design and/or assembly process. These …

Building Oriented Surface Generation Through Iges Specification, Jujiang Bao

Theses

This thesis focuses the use of Initial Graphics Exchange Specification to generate automatically three dimensional surfaces. Currently, different CAD systems utilize their own data formats to generate graphic databases which are not compatible with one another. Besides, most of the existing CAD systems require an interactive data input process which is very much time consuming. In order to solve above problems, an efficient algorithm has been developed in this research to automatically generate portable graphic database following ICES specifications. This portable graphic database can be adopted by different commercial CAD/CAM systems. Using the proposed method, the current design process can …

Development Of An Intelligent Geometry Measurement Procedure For Coordinate Measuring Machines, Tae-Sung Kim

Theses

A Coordinate Measuring Machines (CMM) is a highly accurate electronic scale for the automatic measurement of 2 and 3 dimensional geometries. In a typical operation the CMM measures a set of user defined points, and then utilizes some internal logic to ascertain whether the inspected part meets the specifications. CMMs have received widespread acceptance among the manufacturing community, and in many instances are required as per supplier contract. Applications of CMMs vary from the measurement of simple 2D parts to complex 3D spatial frames (as for example in their use to measure the integrity of automobile frames). The primary objective …