For his final thesis to achieve a PhD in Construction Management, Vicente González examined buffer management in repetitive building projects. In April of 2005, Dr. González was awarded a Research Grant to use Extend for his project. In January of 2008, he co-authored "Work-In-Process Buffer Design Methodology for Scheduling Repetitive Building Projects".

Variability is one of the factors with the largest negative impact in construction projects, which can induce dynamic and unexpected conditions, unsteadying project objectives and obscuring the means to achieve them. A common practice in construction to protect production systems from variability is the use of buffers (Bf). However, current buffering practices in construction are characterized by the intuition and informality leading to poor control of variability. For overcoming these limitations, this research proposes a Bf design methodology based on Work-In-Process (WIP) for scheduling repetitive building projects at tactical and strategic levels. At tactical level, the methodology uses Simulation-Optimization (SO) models to design optimum WIP Bf sizes by different project objectives. Two home building projects implementing the methodology at this level were studied. As a result, improvements on labor productivity and project cost were obtained. At strategic level, a multiobjective model to apply the Bf design methodology was developed, demonstrating its advantages through a project scheduling example. Finally, the impacts of applying WIP Bf strategies based on Lean Production principles are addressed.

	Download final report (664 KB): "Work-In-Process Buffer Design Methodology for Scheduling Repetitive Building Projects" by Vicente González and Luis F. Alarcón
	Download Extend OR 6 model files (5.7 MB). Download the ExtendSim Demo to view these files.

Politechnika Wroclawska
Wroclaw, Poland
Dr. Jacek Zabawa

For over 7 years, students at Politechnika Wroclawska have made many models and projects with Extend, both discrete event and continuous. In the 2006/7 academic year, students focused on:

	Simulation Modeling in Management	mainly discrete models but hybrid, too
	Financial Simulation Models	all forms
	Forecasting and Simulation	discrete models

Students compared Monte Carlo simulations in MS Excel formulas to Extend models, mainly using continuous blocks. Examples from the Liberatore/Nydick book "Introduction to Decision Technology" and Laguna/Marklund's "Business Process Modeling, Simulation, and Design" were studied.

Professor Zabawa wrote three papers about the implementation of Extend in inventory management.

	"Tools Of Monte Carlo Simulation In Inventory Management Problems" written with colleague Dr. Bozena Mielczarek	Presented in June 2007 at the 21st EUROPEAN Conference on Modelling and Simulation ECMS 2007.
	"An Attempt To Comparison Of Inventory Model Implementations In Arena And Extend Environments" written with colleague Dr. Bozena Mielczarek	Reviewed and accepted for presentation in October 2007 at XII INTERNATIONAL CONFERENCE - SYSTEM MODELLING and CONTROL SMC 2007. Comparison of the implementation of simple models in MS Excel, Extend, and Arena.
	"Bull-whip effect in supply chain model"	Reviewed and accepted for presentation and publication in September 2007 at the Scientific School of Simulation of Economic Systems. In this paper, more complex (several modules) supply chain models are presented.

2005/6 Academic Year: Within a few weeks, students would present more sophisticated models containing more advanced blocks, mainly from the continuous library. They studied examples from the Liberatore/Nydick book "Introduction to Decision Technology" and Laguna/Marklund's "Business Process Modeling, Simulation, and Design".

They built a nanomodel of a warehouse system or supplier which could be used for building production systems models and supply chain models, in addition to classroom use. This model was presented at the "Scientific School of Simulation of Economic Systems" in September of 2006.

What began as an MBA class project at Purdue University’s Krannert School of Management is now applying factory management techniques to a medical clinic, ultimately improving productivity and quality. Spearheaded by Professors Herbert Moskowitz and Suresh Chand, the student-faculty team’s approach to improving healthcare clinic operations is, of necessity, “multipronged.” Ultimately, the research applies the principles of engineering, management, science, and information technology to improve the delivery of healthcare to consumers.

Georgetown whets their students' appetites for Operations Management by beginning their core courses with the Benihana case study (HBS 9-673-057). Although originally written in 1972, Benihana remains one of the most popular Harvard Business School cases. The case captivates students because it brings operations to life in a familiar setting; that of a teppanyaki-style restaurant. This simulation of a typical Benihana restaurant is available as a free download.

The Benihana simulation models an evening at Benihana's West 52nd Street restaurant. In addition to emulating customer flow patterns and dinner choices, the Extend model incorporates a sensitivity analysis feature that enables the user to examine the impact of altering the restaurant's capacity, and the bar capacity.

Harvard Business School, Boston, MA USA
MBA Program
Various professors

For a Discrete Systems Simulation course, Professor Charles Winton created a collection of models in Extend. Most of the models illustrate discrete system concepts that Professor Winton came up with when teaching from stock text such as Banks et al.

Prof. Winton's models illustrate constructions that represent phenomena which fit the following discrete event paradigms:
	Basic queueing models
	Priority queues, matching queues, suspending a queue
	Using resources and attributes
	Information capture
	Stability
	Random numbers and probability distributions
	Item generation

You can access the models from Prof. Wintons's web site.

Villanova University's Professor Bob Nydick published a popular textbook with case studies that is being used to teach management science at both the undergraduate and graduate levels. Titled "Introduction to Decision Technology", the textbook shows how to apply three management science modules: mathematical programming with LINGO (linear, integer, and non-linear), decision analysis using Expert Choice (primarily the Analytic Hierarchy Process [AHP]), and simulation using Extend (primarily discrete event).

The course packet includes a textbook bundled with a CD that contains student (limited) versions of the three commercial applications. All model files referenced in the text, as well as explanatory and computer model files relating to the homework problems, are provided. The book can be customized to deliver one, two, or all three modules as desired.

The textbook has been used at universities such as Stanford University, California; Washington University, St. Louis; The University of Tennessee, Tennessee; Fairfield University, Connecticut; and Pace University, New York among many others. To learn more, see Academic Textbooks.