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Operations Research, Systems Engineering and Industrial Engineering Commons

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Series

Iowa State University

2005

Articles 1 - 13 of 13

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Learning Streams: A Case Study In Curriculum Integration, Mani Mina, Arun K. Somani, Akhilesh Tyagi, Diane T. Rover, Matthew Feldmann, Mack C. Shelley Oct 2005

Learning Streams: A Case Study In Curriculum Integration, Mani Mina, Arun K. Somani, Akhilesh Tyagi, Diane T. Rover, Matthew Feldmann, Mack C. Shelley

Political Science Presentations and Posters

During 2004-2005, the Departments of Electrical and Computer Engineering and Mechanical Engineering at Iowa State University in collaboration with educational colleagues in the Research Institute for Studies in Education piloted a new curricula model to improve student learning through vertical integration of educational activities using new program structures. We offered an experimental course sequence during Fall 2004 and Spring 2005, defined as a “learning stream.” A learning stream is a basic element of a novel program structure designed specifically to vertically integrate subject matter across courses. A learning stream merges and re-organizes material to more effectively present and reinforce key ...


Engineering Problem Solving In Industrial Engineering Curriculum Reform, Veronica J. Dark, Frank Peters, Sarah M. Ryan, John K. Jackman, Sigurdur Olafsson Jun 2005

Engineering Problem Solving In Industrial Engineering Curriculum Reform, Veronica J. Dark, Frank Peters, Sarah M. Ryan, John K. Jackman, Sigurdur Olafsson

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Problem solving is a major focus of the engineering profession, and upon graduation new engineers are faced with increasingly complex problems. Yet, existing engineering education practices often fall short in preparing students to tackle complex engineering problems that may be ambiguous, open-ended and ill-structured. In this paper, we describe a newly developed learning environment called the Engineering Learning Portal (ELP), which focuses on improving engineering problem solving throughout the industrial engineering curriculum. In the ELP, students are engaged in a structured process for solving unstructured problems while encouraging metacognitive activities, such as planning, monitoring, and evaluating. This helps students acquire ...


Selection Of Products And Prices In Manufacturing And Remanufacturing Environment, Sasidhar Malladi, K. Jo Min Jan 2005

Selection Of Products And Prices In Manufacturing And Remanufacturing Environment, Sasidhar Malladi, K. Jo Min

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

In this paper, we consider a manufacturer who produces both new and remanufactured products facing a group of heterogeneous customers who self-select their optimal choices of products. Under such circumstances, we formulate a mathematical programming model that determines the products, prices, and acquisition prices for used products. Based on this model, we will discuss conditions under which remanufacturing can be encouraged.


Coordinating Forward And Reverse Flows Of Products For A Manufacturer-Retailer Supply Chain Model, Jie Li, K. Jo Min Jan 2005

Coordinating Forward And Reverse Flows Of Products For A Manufacturer-Retailer Supply Chain Model, Jie Li, K. Jo Min

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

In this paper, we formulate and analyze a manufacturer-retailer supply chain model with product remanufacturing. This model takes into account both forward flow of the new product as well as reverse flow of the used product. Specifically, we assume that the manufacturer can control the wholesale price of the new product as well the transfer price of the used product from the retailer while the retailer can control the retail price of the new product and the collecting price of the used product. Under this assumption, we compare and contrast the coordinated scenario vs. the uncoordinated scenario. Managerial insights and ...


The Use Of Sacrificial Support Structures In A Rapid Machining Process, Wutthigrai Boonsuk, Matthew C. Frank Jan 2005

The Use Of Sacrificial Support Structures In A Rapid Machining Process, Wutthigrai Boonsuk, Matthew C. Frank

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Rapid prototyping techniques for CNC machining have been developed in an effort to produce functional prototypes in appropriate materials. One of the major challenges is to develop an automatic fixturing system for the part during the milling process. The current proposed method, sacrificial support fixturing, is similar to the support structures used in existing rapid processes, such as Stereolithography. During the machining process, the sacrificial supports emerge incrementally and, at the end of the process, are the only entities connecting the part to the stock material. In this paper, we propose methodologies for the design of sacrificial support structures for ...


Capacity Expansion For Uncertain Demand With Initial Shortages, Rahul R. Marathe, Sarah M. Ryan Jan 2005

Capacity Expansion For Uncertain Demand With Initial Shortages, Rahul R. Marathe, Sarah M. Ryan

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

For service providers, uncertain demand for capacity and expansion lead time may create unavoidable capacity shortages, which may be allowed to accumulate before initiating an expansion. For the demand following a geometric Brownian motion process, we assume a stationary expansion policy where the timing and size of expansion are determined as fixed proportions of the capacity position. We define the service level in terms of the capacity shortages, which can be evaluated by applying pricing formulae for barrier options in finance. We observe the relationship between the two policy parameters at different specified service levels and for other model parameters.


Allocating Work In Process In A Multiple-Product Conwip System With Lost Sales, Sarah M. Ryan, Jumpol Vorasayan Jan 2005

Allocating Work In Process In A Multiple-Product Conwip System With Lost Sales, Sarah M. Ryan, Jumpol Vorasayan

Industrial and Manufacturing Systems Engineering Publications

To operate a multiple-product manufacturing system under a CONWIP control policy, one must decide how to assign kanbans to products. With a fixed total number of kanbans in a competitive environment, the goal is to determine their allocation to product types in order to minimize lost sales equitably. In particular, we consider systems in which the products may make multiple visits to the same station with a different processing time distribution on each repeat visit. With a fixed number of kanbans dedicated to each product, the system is modeled as a multiple-chain multiple-class closed queuing network. A nonlinear program simultaneously ...


Likelihood-Based Statistical Estimation From Quantized Data, Stephen B. Vardeman, Chiang-Sheng Lee Jan 2005

Likelihood-Based Statistical Estimation From Quantized Data, Stephen B. Vardeman, Chiang-Sheng Lee

Industrial and Manufacturing Systems Engineering Publications

Most standard statistical methods treat numerical data as if they were real (infinite-number-of-decimal-places) observations. The issue of quantization or digital resolution can render such methods inappropriate and misleading. This article discusses some of the difficulties of interpretation and corresponding difficulties of inference arising in even very simple measurement contexts, once the presence of quantization is admitted. It then argues (using the simple case of confidence interval estimation based on a quantized random sample from a normal distribution as a vehicle) for the use of statistical methods based on "rounded data likelihood functions" as an effective way of handling the matter.


Sheppard's Correction For Variances And The "Quantization Noise Model", Stephen B. Vardeman Jan 2005

Sheppard's Correction For Variances And The "Quantization Noise Model", Stephen B. Vardeman

Industrial and Manufacturing Systems Engineering Publications

In this paper, we examine the relevance of Sheppard's correction for variances and (both the original and a valid weak form of) the so-called "quantization noise model" to understanding the effects of integer rounding on continuous random variables. We further consider whether there is any real relationship between the two. We observe that the strong form of the model is not really relevant to describing rounding effects. We demonstrate using simple cases the substantial limitations of the Sheppard correction, and use simple versions of a weak form of the model to establish that there is no real connection between ...


Likelihood And Bayesian Methods For Accurate Identification Of Measurement Biases In Pseudo Steady-State Processes, Sriram Devanathan, Stephen B. Vardeman, Derrick K. Rollins Sr. Jan 2005

Likelihood And Bayesian Methods For Accurate Identification Of Measurement Biases In Pseudo Steady-State Processes, Sriram Devanathan, Stephen B. Vardeman, Derrick K. Rollins Sr.

Industrial and Manufacturing Systems Engineering Publications

Two new approaches are presented for improved identification of measurement biases in linear pseudo steady-state processes. Both are designed to detect a change in the mean of a measured variable leading to an inference regarding the presence of a biased measurement. The first method is based on a likelihood ratio test for the presence of a mean shift. The second is based on a Bayesian decision rule (relying on prior distributions for unknown parameters) for the detection of a mean shift. The performance of these two methods is compared with that of a method given by Devanathan et al. (2000 ...


On The Validity Of The Geometric Brownian Motion Assumption, Rahul Ratnakar Marathe, Sarah M. Ryan Jan 2005

On The Validity Of The Geometric Brownian Motion Assumption, Rahul Ratnakar Marathe, Sarah M. Ryan

Industrial and Manufacturing Systems Engineering Publications

The geometric Brownian motion (GBM) process is frequently invoked as a model for such diverse quantities as stock prices, natural resource prices and the growth in demand for products or services. We discuss a process for checking whether a given time series follows the GBM process. Methods to remove seasonal variation from such a time series are also analyzed. Of four industries studied, the historical time series for usage of established services meet the criteria for a GBM; however, the data for growth of emergent services do not.


Ontologies For Supporting Engineering Analysis Models, Ian R. Grosse, John M. Milton-Benoit, Jack C. Wileden Jan 2005

Ontologies For Supporting Engineering Analysis Models, Ian R. Grosse, John M. Milton-Benoit, Jack C. Wileden

Center for e-Design Publications

In this paper we lay the foundations for exchanging, adapting, and interoperating engineering analysis models (EAMs). Our primary foundation is based upon the concept that engineering analysis models are knowledge-based abstractions of physical systems, and therefore knowledge sharing is the key to exchanging, adapting, and interoperating EAMs within or across organizations. To enable robust knowledge sharing, we propose a formal set of ontologies for classifying analysis modeling knowledge. To this end, the fundamental concepts that form the basis of all engineering analysis models are identified, described, and typed for implementation into a computational environment. This generic engineering analysis modeling ontology ...


Detecting Inconsistency In Functional Software Requirements, Gboyega Sanni, John K. Jackman Jan 2005

Detecting Inconsistency In Functional Software Requirements, Gboyega Sanni, John K. Jackman

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Success in software development depends on the availability of complete, consistent, and unambiguous functional software requirements. Inconsistencies in software requirements can propagate problems throughout the development cycle. We introduce the concept of a quantitative measure for detecting inconsistencies, namely, Potential Structural Inconsistency (PSI). This measure is derived from a structural model for a given set of requirements. We show how this measure can be determined using a case study with known inconsistencies.