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Articles 781 - 810 of 849

Full-Text Articles in Industrial Engineering

Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell Jan 2010

Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

This research determines time optimal routes for loading and picking pallets that can be stacked on top of each other during transport in a manual warehouse that only contains full pallets and utilizes single deep storage. This research was motivated by the fact that we are seeing this situation on an ever increasing basis, particularly in warehouses that supply parts to automotive assembly. In practice, forklift drivers have developed strategies to take advantage of this opportunity but to our knowledge there is no literature that addresses this problem rigorously. The important features of this work are that a time based …


Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue Jan 2010

Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

One disadvantage of automated material handling systems is their relative Inflexibility: once racks are installed and conveyors are laid, making even mi-nor changes to a system can be cumbersome and expensive. However, recent progress in the capabilities and cost of basic system components, such as controllers, drives, and sensors, has made possible a new class of material handling systems having a much higher degree of flexibility. We propose underlying de- sign principles for such systems and describe several prototype plug-and-work" systems, which feature decentralized control and ease of reconfiguration.


Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden Jan 2010

Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

New types of Automated Storage and Retrieval Systems, able to achieve high throughput levels, are continuously being developed and require new control polices to take full advantage of the developed system. In this paper we study a dynamic storage system as developed by Vanderlande Industries consisting of a conveyor, two lifts, multiple transfer shuttles, and a storage rack. One of the decision problems for this system is the scheduling problem of the two lifts. In other words, which lift is going to handle which request and in which order. In this paper, we derive an integrated look-ahead heuristic based on …


Course Portfolio - Discrete Event Simulation, Paul Savory Oct 2009

Course Portfolio - Discrete Event Simulation, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

This course portfolio, written by Dr. Paul Savory, provides an overview of his Discrete Event Simulation course at the University of Nebraska-Lincoln. It offers an overview of the course goals, a summary of the classroom activities for achieving them, and a detailed assessment of student learning. He highlights his introduction of the simul8 programming environment to his students. In addition to exploring his students’ learning, Dr. Savory also explores different approaches for documenting his teaching by including multimedia clips (video and audio), uses graphs, uses color, and incorporates images. The resulting portfolio is one that can be reviewed, shared, and …


An Analytical Framework And Model Formulation For Measuring Risk In Engineering Enterprise Systems: A Capability Portfolio Perspective, Paul Raphael Garvey Jul 2009

An Analytical Framework And Model Formulation For Measuring Risk In Engineering Enterprise Systems: A Capability Portfolio Perspective, Paul Raphael Garvey

Engineering Management & Systems Engineering Theses & Dissertations

This work formulates an analytical framework and computational model for assessing risk in engineering enterprise systems. It addresses the engineering management problem of how to represent, model, and measure risk in large-scale, complex systems engineered to function in enterprise-wide environments.

The research in this dissertation extends current practice in the management of risk for traditional systems and creates new constructs and protocols for the management of risk in engineering large-scale, complex, and highly networked enterprise systems. This work advances engineering management theory and analytic practice as applied to the measurement and management of risk for enterprise systems engineered within capability …


Rubric For Presentation Evaluation, Paul Savory Jan 2009

Rubric For Presentation Evaluation, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

I have developed this rubric to allow classmates and myself to offer an evaluation or assessment of a student classroom presentation. It is my attempt to develop a standardized evaluation linked to specified criteria, making the grading process simpler and more transparent.


Rubric For Project Report Evaluation, Paul Savory Jan 2009

Rubric For Project Report Evaluation, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

I have developed this rubric to formalize the evaluation or assessment of a project report. It is my attempt to develop a standardized evaluation linked to specified criteria, making the grading process simpler and more transparent.


Rubric For Project Self-Evaluation, Paul Savory Jan 2009

Rubric For Project Self-Evaluation, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

I have developed this rubric to allow each member of a project team to offer a self-assessment of their own performance on the projects. It is my attempt to develop a standardized evaluation linked to specified criteria, making the grading process simpler and more transparent.


Ruberic For Project Team Member Evaluation, Paul Savory Jan 2009

Ruberic For Project Team Member Evaluation, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

I have developed this rubric to allow team members for course projects to offer an evaluation or assessment of the fellow members of their team. It is my attempt to develop a standardized evaluation linked to specified criteria, making the grading process simpler and more transparent.


Multi-Objective Network Reliability Optimization Using Evolutionary Algorithms, Franciso Oswaldo Aguirre Jan 2009

Multi-Objective Network Reliability Optimization Using Evolutionary Algorithms, Franciso Oswaldo Aguirre

Open Access Theses & Dissertations

This work presents a new multiple objective evolutionary algorithm to solve three well known network reliability allocation problems considering different conflicting objectives to be optimized simultaneously. The new algorithm is applied in the design of a telecommunication network that is formed for several stations or nodes interconnected by telecommunication links or paths. The problem presented in this work involves finding which links to activate in order to obtain connectivity in the nodes. The number of nodes that need to be connected depends of the case that is being evaluated. The three network reliability problems considered are: all-terminal, k-terminal, and two-terminal. …


Randomly Generating Manufacturing Flow Line Models Using Mathematica, Paul Savory Jul 2008

Randomly Generating Manufacturing Flow Line Models Using Mathematica, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

To test heuristic algorithms and techniques, researchers need numerous datasets so as to measure effectiveness and improve approaches. This paper discusses using Mathematica, a mathematical programming language, for randomly generating the specifications for manufacturing flow line models. Important issues include determining an arrival rate to a flow line, the number of flow line stations, the number of parallel servers for each production station, and specifying the service time distributions and their associated parameters. The paper concludes with a discussion on generating more general types of simulation models.


Cost Of Manufacturing: Experiment To Establish Process-Specific Cost Functions For A Deviation Based Cost Formulation, Parikshit Rajendra Deshmukh Jan 2008

Cost Of Manufacturing: Experiment To Establish Process-Specific Cost Functions For A Deviation Based Cost Formulation, Parikshit Rajendra Deshmukh

Graduate Research Papers

In the present day global competition, there is incredible pressure on manufacturing unit of a company to reduce the cost of manufacturing, so that company can offer products at low cost. Cost of manufacturing is essential to determine final cost of the product. The cost depends on the type of manufacturing techniques used and the desired level of tolerance, it varies with the tolerance. To formulate the detail cost of manufacturing all the geometric tolerance given has to be evaluated including material, dimensions and machining operations. It is vital to the survival of any business to forecast more effectively the …


Details And Description Of Operations Research, Paul Savory Jan 2007

Details And Description Of Operations Research, Paul Savory

Department of Industrial and Management Systems Engineering: Reports

The ambiguous term operations research was coined during World War II. A frequent substitute is management science. Operations research is a scientific approach to analyzing problems and making decisions. It uses mathematics and mathematical modeling on computers to forecast the implications of various choices and zero in on the best alternatives. This content paper provides an overview of operations research. It highlights operations research problems, methods for solving problems, different areas of operations research, and example problems.


Pre/Post Assessment Of Abilities, Paul Savory Jan 2007

Pre/Post Assessment Of Abilities, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

One approach to assess if students are learning in a course is to conduct a pre-test, post-test assessment of the course material. By comparing the two results, one can make an assessment of the knowledge learned in the course. For certain types of courses, it can be a challenge in defining an assessment instrument that measure student knowledge. This example is one I have developed for my IMSE 440/840 (Discrete Event Computer Simulation) course. Students are asked rate their ability for key course objectives defined on the course syllabus. I administer it on the first day of the course and …


Methodology For Analyzing And Characterizing Error Generation In Presence Of Autocorrelated Demands In Stochastic Inventory Models, Rafael Diaz Jan 2007

Methodology For Analyzing And Characterizing Error Generation In Presence Of Autocorrelated Demands In Stochastic Inventory Models, Rafael Diaz

Computational Modeling & Simulation Engineering Theses & Dissertations

Most techniques that describe and solve stochastic inventory problems rely upon the assumption of identically and independently distributed (IID) demands. Stochastic inventory formulations that fail to capture serially-correlated components in the demand lead to serious errors. This dissertation provides a robust method that approximates solutions to the stochastic inventory problem where the control review system is continuous, the demand contains autocorrelated components, and the lost sales case is considered. A simulation optimization technique based on simulated annealing (SA), pattern search (PS), and ranking and selection (R&S) is developed and used to generate near-optimal solutions. The proposed method accounts for the …


Exact And Heuristic Algorithms For The Job Shop Scheduling Problem With Earliness And Tardiness Over A Common Due Date, Leonardo Bedoya-Valencia Jan 2007

Exact And Heuristic Algorithms For The Job Shop Scheduling Problem With Earliness And Tardiness Over A Common Due Date, Leonardo Bedoya-Valencia

Engineering Management & Systems Engineering Theses & Dissertations

Scheduling has turned out to be a fundamental activity for both production and service organizations. As competitive markets emerge, Just-In-Time (JIT) production has obtained more importance as a way of rapidly responding to continuously changing market forces. Due to their realistic assumptions, job shop production environments have gained much research effort among scheduling researchers. This research develops exact and heuristic methods and algorithms to solve the job shop scheduling problem when the objective is to minimize both earliness and tardiness costs over a common due date. The objective function of minimizing earliness and tardiness costs captures the essence of the …


Process Modelling Support For The Conceptual Modelling Phase Of A Simulation Project, Cathal Heavey, John Ryan Dec 2006

Process Modelling Support For The Conceptual Modelling Phase Of A Simulation Project, Cathal Heavey, John Ryan

Conference papers

While many developments have taken place around supporting the model coding task of simulation, there are few tools available to assist in the conceptual modelling phase. Several authors have reported the advantages of using process modelling tools in the early phases of a simulation project.

This paper provides an overview of process modelling tools in relation to their support for simulation, categorizing the tools into formal method and descriptive methods. A conclusion from this review is that none of the tools available adequately support the requirements gathering phase of simulation. This is not surprising as none of the process modelling …


Process Modeling For Simulation, John Ryan, Cathal Heavey Jan 2006

Process Modeling For Simulation, John Ryan, Cathal Heavey

Articles

This paper discusses shortfalls in relation to the requirements gathering phases of simulation. While many developments have taken place around supporting the model coding task of simulation, there are few tools available to assist in the requirements gathering phase. This is surprising as it has been reported by several researchers that the requirements phase can absorb twice as much resources as the coding phase. There are numerous process modeling tools available (over 100) that can and have been used to support the requirements phase of simulation. This paper provides a selective review of some of the most important in relation …


Class Exercise For Assessing Abilities And Providing A Structure For A Course, Paul Savory Jan 2006

Class Exercise For Assessing Abilities And Providing A Structure For A Course, Paul Savory

Department of Industrial and Management Systems Engineering: Instructional Materials

I developed this class exercise to assess students abilities and to highlight the range of questions/issues that they will learn in my IMSE 440/840 (Discrete Event Computer Simulation) course. I draw a picture of the case scenario for students and explain the system’s operation to them. I then ask that they complete the questions regarding the system and/or how they would analyze it. Following class, I develop a summary of the range of student answers. At the next class session, I share the range of answers and share what my answers would be and how these questions/topics relate to what …


A Template-Based Data Specification Framework For Modeling Physical Security Systems, Ashu Guru, Paul Savory Jan 2006

A Template-Based Data Specification Framework For Modeling Physical Security Systems, Ashu Guru, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Simulation studies often fail to provide any useful results due to its success being highly dependent on the skills of the analyst to understand a system and then correctly identify all the required data parameters and dependent variables. This paper describes a template-based framework to help identify and specify the components and data parameters for developing models of physical security systems. The layered framework consists of fifteen templates built on top of fourteen data primitives representing 119 data parameters. The modeling framework has been programmed as an internet-based web application and is simulation language independent. The usefulness of the framework …


A Systems Methodology For Measuring Operational Organization Effectiveness: A Study Of The Original Equipment Computer Manufacturing Industry, 1948 To 2001, Teddy Steven Cotter Apr 2005

A Systems Methodology For Measuring Operational Organization Effectiveness: A Study Of The Original Equipment Computer Manufacturing Industry, 1948 To 2001, Teddy Steven Cotter

Engineering Management & Systems Engineering Theses & Dissertations

Optimizing operational organizational effectiveness is the central, although often unstated, goal of engineering management and systems engineering research and applications. Two fundamental problems remain to be addressed in pursuit of this goal. First, despite over fifty years of research in various disciplines, there is still no universally accepted definition of organizational effectiveness. Second, no methodology exists to identify the domains, dimensions, and determinants of operational organizational effectiveness and dynamically model operational organizational effectiveness within a given population.

This research synthesizes a systems engineering methodology for identifying the domains, dimensions, and determinants of and dynamically modeling operational organizational effectiveness for an …


Development Of A Process Modelling System For Simulation, John Ryan Jan 2005

Development Of A Process Modelling System For Simulation, John Ryan

Other resources

This thesis details the development of a process modelling technique to aid a simulation model developer during the requirements gathering and conceptual modelling phases of a simulation project.

There are a number of process modelling techniques available that are capable of being used during such phases of a simulation project, however there is currently a lack of process modelling techniques developed specifically to aid a simulation model developer in capturing, representing and communicating information and systems issues to persons involved in the operation of discrete systems under investigation.

A detailed review of the literature related to techniques capable of supporting …


Haptic-Based Dental Procedure Training Simulator, Cristian Luciano Jan 2005

Haptic-Based Dental Procedure Training Simulator, Cristian Luciano

Link Foundation Modeling, Simulation and Training Fellowship Reports

Since the beginning of the last century, simulators have been widely used in military and aviation. Recently, the use of simulation in medicine and dentistry has brought the attention of the research community, looking for efficient ways to increase patient's safety by improving surgeon's and dentist's skills. Traditionally, plastic mannequins and cadavers were used to train medical and dental students. However, the lack of details and differences on material properties (in the case of mannequins), and high costs and ethical issues (in the case of cadavers)- supported by the lately improvements of virtual reality, haptics and robotics - have increased …


A Case Study Of Teaching A Quantitative Course Using Archived Streaming Video, Paul Savory Oct 2004

A Case Study Of Teaching A Quantitative Course Using Archived Streaming Video, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

This case study highlights some of the issues and difficulties experienced in teaching a quantitative course using three methods of delivery: in-class to an audience of students, television broadcast over a satellite system to distance students, and archived streaming video accessible by students. The discussion is applicable to administrators and faculty exploring the option of teaching a course using multiple delivery approaches.


Lean Energy Analysis: Identifying, Discovering And Tracking Energy Savings Potential, J. Kelly Kissock, John Seryak Oct 2004

Lean Energy Analysis: Identifying, Discovering And Tracking Energy Savings Potential, J. Kelly Kissock, John Seryak

Mechanical and Aerospace Engineering Faculty Publications

Energy in manufacturing facilities is used for direct production of goods, space conditioning, and general facility support such as lighting. This paper presents a methodology, called lean energy analysis, LEA, for graphically and statistically analyzing plant energy use in terms of these major end uses.

The LEA methodology uses as few as 60 easily obtainable data points. Multivariable change-point models of electricity and natural gas use as functions of outdoor air temperature and production data are developed. The statistical models are used to subdivide plant energy use into facility, space-conditioning and production-related components.

These breakdowns suggest the savings potential from …


A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Paul Savory Oct 2004

A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Although simulation is one of the most innovative and cost-effective tools for modeling and analyzing a system, simulation studies often fail to provide any useful results. One reason is attributed to the fact that model formulation depends on the skills of the analyst. This paper describes a research to develop a conceptual modeling infrastructure to assist a simulation analyst in specifying components for studying physical security systems. The modeling framework has been programmed as an internet-based web application. Using the application, the successful development and implementation of a physical security simulation model will be aided by a defined scientific methodology …


Combining Systematic Layout Planning And Computer Simulation In The Design Of Manufacturing Facilities, Akintoye M. Akinyoade May 2004

Combining Systematic Layout Planning And Computer Simulation In The Design Of Manufacturing Facilities, Akintoye M. Akinyoade

All-Inclusive List of Electronic Theses and Dissertations

In this study, the systematic layout planning (SLP) and computer simulation were combined to improve the layout design of a manufacturing facility using a case study.


Optimization-Based Architecture For Managing Complex Integrated Product Development Projects, Hisham Mohamed El-Sayed Abdelsalam Jul 2003

Optimization-Based Architecture For Managing Complex Integrated Product Development Projects, Hisham Mohamed El-Sayed Abdelsalam

Mechanical & Aerospace Engineering Theses & Dissertations

By the mid-1990's, the importance of early introduction of new products to both market share and profitability became fully understood. Thus, reducing product time-to-market became an essential requirement for continuous competition. Integrated Product Development (IPD) is a holistic approach that helps to overcome problems that arise in a complex product development project. IPD emphasis is to provide a framework for an effective planning and managing of engineering projects. Coupled with the fact that about 70% of the life cycle cost of a product is committed at early design phases, the motivation for developing and implementing more effective methodologies for managing …


Development Of A Multicriteria Spatial Decision Support System With Application To The Economic Optimization Of Aircraft Based Weather Data Collection, Ganzague Erol Osman Ozan Jul 2003

Development Of A Multicriteria Spatial Decision Support System With Application To The Economic Optimization Of Aircraft Based Weather Data Collection, Ganzague Erol Osman Ozan

Engineering Management & Systems Engineering Theses & Dissertations

This research is motivated by the economic optimization of the Troposherical Airborne Meteorological Data Reporting (TAMDAR), an aircraft-based meteorological data collection system. In the envisioned TAMDAR system, meteorological data collected by the onboard sensors of selected aircraft are transmitted to the ground as aircraft fly their missions. The data is processed by a national center, which disseminates the data to diverse users such as weather forecasters and aviation control centers. Substantial government funding is required for the implementation and operation of this new data acquisition system and data transmission expenditures constitute the largest portion of the costs. To achieve economic …


Information System Product Development By Integration Of Kano's Customer Satisfaction Model With Quality Function Deployment, Afife Yesim Sireli Jul 2003

Information System Product Development By Integration Of Kano's Customer Satisfaction Model With Quality Function Deployment, Afife Yesim Sireli

Engineering Management & Systems Engineering Theses & Dissertations

Product development of complex, innovative information technology related systems presents difficult challenges for technology managers, and new product failures are a significant problem. The main reason for this is insufficient decision-making due to the lack of a customer-oriented product development process in the information system (IS) companies, which is often related to deficiencies in cooperation between R&D and marketing departments. Integrating consumer requirements into the product design phase is an important factor for improving market success. Therefore, a product development decision model is needed for the managers of information system companies to make more accurate decisions about the characteristics of …