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Leo's Page Thank you for taking the time to check out my corner of the
World Wide Web. My name is Leonardo Lopes, but everyone knows me
as Leo. I am an Assistant Professor in the Systems and Industrial
Engineering Department at the University of Arizona. I am one of
the inventors of the Network Elucidation Template, a framework
that uses optimization, probability, statistics, and network
topology to infer missing network parameters. On these pages you
will find more detailed information about my activities. If you
find something of interest please contact
me.
For appointment availability, check my public calendar |
Ph.D., Industrial Engineering and Management Sciences - Northwestern University, 2003
Dissertation Topic:Modeling and Communication of Stochastic Programs
My research focus is on human-centric stochastic network optimization. My goal is to enable efficient creation of complex models from simpler models for any application where significant sources of uncertainty exist. We build these models by using the appropriate combination of statistics, optimization, and human guidance for each application, and by creating infrastructure that promotes model reuse and distribution over grids. Our work has two facets:
Modeling: representing the essential aspects of concrete problems as (usually, but not always, mathematical) objects and using those objects to improve decsion-making.
Computational Optimization: developing algorithms that combine the right amount of mathematical theory and brute force to take advantage of modern computing architectures
Each of the two areas above is very different from the other. They are both essential for the success of the overall vision. Which area gets developed faster is a function of the student talent available. I have current projects both for students interested mostly on mathematical concepts, and students interested mostly in computational issues. Working with me, students will develop decent competency in both mathematical and computational research (we operate continuously right on their intersection), but are welcome to focus on one more than the other.
Most likely paths and
flows: Modern interfaces for communicating instances of
optimization problems.
XML and Communication of
Optimization Problems: Modern interfaces for communicating
instances of optimization problems.
Modeling of Stochastic
Programming: An Integrated Development Environment for
modeling, solving, and analysing Stochastic Programming Problems.
This research may be at several levels of development. In some cases, all proofs have been written, but no computational experiments have been performed. In others, grants have been written but most of the research has not been done. In others, the problem has been defined, but the exact scope of each project is not yet determined. Students interested in extending these topics will have extraordinary freedom to determine their own research directions.
Stochastic
Optimization IT infrastructure
Modern mathematical
programming environments use diverse tools and computing resources.
The challenge addressed by this research is to invent a
computational framework, including exchange mechanisms, libraries,
and protocols to enable the development of ever more powerful,
easier to use, and cheaper to deploy mathematicalprogramming tools.
This is research on which I have worked in the past, but on which I am no longer active unless the right application, collaborator or funding comes along.
HUGS and the Job Shop
Problem: Using Human Guided Search to develop solutions to
the Job Shop Problem.
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Power of
Two Policies A Java illustration of Power of Two policies for
the Single Item Multi-Retailer problem.
Project
Mapper - A tool for automatic generation of Linear Programming
Problems modeling network flow problems using graphs (undergraduate
sponsored research project).
Since August of 2004, I am an Assistant Professor at the Department of Systems and Industrial Engineering at the University of Arizona in Tucson. I am teaching, learning about writing grants from some of the best in the business, and getting involved with some very interesting research problems, in addition to working on my own research initiatives. It has been a very busy but very rewarding experience.
From August of 2003 to August of 2004 I was a Visiting Assistant Professor at the Department of Systems and Industrial Engineering at the University of Arizona.
From 1997 to 2003, I was a research assistant at Northwestern University under different grants. I worked briefly on an integrated Location, Transportation and Inventory management system. From 1998 to 2003 I worked on optimization modeling systems.
In the summer of 1997, I worked for the NEOS project. I helped build a driver for the solver KNITRO, using Automatic Differentiation to produce derivatives. I also created a script that allowed modelers to use derivatives obtained from Maple in their NEOS submissions.
In the summer of 2000, I had an intership at Cambridge Research Laboratories, formerly MERL, in which we developed a Job-shop problem application based on HUGS, an optimization approach for highly combinatorial problems.
I was a System Administrator at the Departament of Mathematics at UFC. We managed the connection of the department to the internet and installed and maintain UNIX, Windows and Windows95 workstations. Our UNIX flavors were Linux, AIX and Solaris. Our team took care in three shifts of four labs with over 150 users, also offering trainging for the users and the less experienced administrators.
I also designed and installed the Network infrastructure including internet connection for PCC Informática, as described in the article I published in the February '98 issue of Linux Gazette.
From April to September 1997 I was a developer at Townsend Analytics, a real-time trading software company. While there, I wrote software that dealt with clearing, and I automated the company-wide build process.
If you have read this far, it is probably because you are thinking of what it would be like to work with me. If you are really looking for something personal, I am afraid you will be disappointed, since this is my professional website. The only truly personal item I will divulge here is the (non-techincal) book I am currently reading: Hernani, and El Rey Se Divierte, two plays by Victor Hugo in Spanish.
Professionally, I emphasize four things: perspiration over inspiration; transparency; diversity; and something I call "reverse greed", which depends on the other three. Reverse greed means that I will let you know what my goals are, and you should let me know what your goals are. I will then do my best to help you achieve your goals so long as you are doing your best to help me achieve mine.
