Grisselle Centeno

A systematic approach for resource allocation in software projects

The completion of reliable software products within their expected time frame represents a major problem for companies that develop software applications. Today, the software industry continues to struggle with delivering products in a timely manner. A major cause for delays is the training time required for engineers and other personnel to acquire the necessary skills to complete software tasks. Therefore, it is important to develop systematic personnel assignment processes that consider complete skill sets of candidates to provide solutions that reduce training time. This paper presents a novel methodology to assign resources to tasks when optimum skill sets are not available. The methodology takes into account existing capabilities of candidates, required levels of expertise, and priorities of required skills for the task. A sample case is used to show the model capabilities, and the results are compared with the current resource assignment approach.

Parallel machine scheduling with release time and machine eligibility restrictions

Abstract We present an algorithm for the problem of minimizing maximum lateness in a parallel machine environment with release dates and machine eligibility restrictions (P m | r j , M j | L max ) for the special case where due dates are equal to release dates plus a constant. No preemption of jobs is allowed. The algorithm has been evaluated using real data from an operational environment of a semiconductor manufacturing firm. Comparison is also made with the actual scheduling system being used by the organization.

Stochastic integer programming models for reducing wastages and shortages of blood products at hospitals

Major challenges in the management of the blood supply chain are related to the shortage and wastage of the blood products. Given the perishable characteristics of this product, storing an excessive number of blood units on inventory could result on the wastage of this limited resource. On the other hand, having shortages may result in cancellations of critical health related activities and as a result a potential increase on fatality rates at hospitals.This paper presents integer programming models to minimize the total cost, shortage and wastage levels of blood products at a hospital within a planning horizon. The primary focus is on the red blood cells and the platelet components of the whole blood cells. The stochastic and deterministic models included consider uncertain demand rates, demand for two types of patients, and crossmatch-to-transfusion ratio. Results show wastage rates decreasing from 19.9% to 2.57% on average. In addition, the shortages and total cost are reduced 91.43% and 20.7% respectively for a given capacity increases. Computational results are included and discussed.

Scheduling with flexible resources in parallel workcenters to minimize maximum completion time

In this paper we consider the parallel machine scheduling problem with dual resource constraints with the objective of minimizing the maximum completion time. We develop heuristics that combine list-scheduling and bin-packing approaches with rules to iteratively modify the flexible resource allocation. A lower bound is presented and the previous and proposed solution approaches to the problem are analyzed under a variety of experimental conditions, demonstrating that there are advantages to the proposed heuristics.

Minimizing the number of late jobs for the permutation flowshop problem with secondary resources

This paper considers a permutation flowshop problem with secondary resources with the objective of minimizing the number of tardy jobs. The number of secondary resources assigned to the machines (workcenters), as well as the allocation of resources among the various machines, will play a significant role in the time required to process each job by its specified due date. This problem finds application in a large number of environments including manufacturing, maintenance, warehousing operations, as well as in healthcare. The research presents a lower bound for the permutation flowshop problem and evaluates its performance against the optimal solution for small, medium, and large instances. Several heuristics, including neighborhood search and simulated annealing, are presented to generate the secondary resource assignment and the allocation of jobs to the schedule. The computational complexity of the lower bound and computational examples for the heuristics are discussed.

A research initiative to close the gap between undergraduate and graduate school in engineering

Recent statistics indicate a declining population of undergraduate engineering students that continue toward advanced engineering degrees. This steady downturn in the number of graduate engineering students has fueled fears that the future of the nations manufacturing and high technology industry is damaged by a severe shortage of skilled engineers unless urgent steps are taken to halt and reverse the decline. In response, The College of Engineering (CoE) at the University of South Florida implemented an internal research experience for undergraduates (REU) initiative designed to provide the student with a valuable research encounter. What has resulted is an important retention in the number of engineering undergraduate students enrolling in our graduate program following their REU experience and a systematic approach to integrate a large number of undergraduate students into the research efforts of the college. In this paper we describe our experience and provide guidance for other interested institutions to implement this initiative. Our initial results show that 64% of our graduates continued toward graduate engineering degrees as a direct result of their research experience.

A fuzzy goal programming model for skill-based personnel assignments

This research develops a fuzzy goal programming (FGP) model for personnel assignment decisions in skill-based environments. Although FGP has been applied to various areas within the management science and operations research literature, a FGP model has not been proposed within the skill-based personnel assignment literature. The paper develops a methodology denoted as membership function relaxation to directly involve decision makers in the process of constructing fuzzy sets and determine priorities of assignment criteria, thus resulting in a more complete decision structure for assignment problems that could lead to higher practical values. An assignment problem in a software development industrial setting is presented to demonstrate the proper implementation of the solution approach. Two software engineering field experts acted as decision-makers and participated in the development of the fuzzy sets for the goals.

A DEA–Tobit Analysis to Understand the Role of Experience and Task Factors in the Efficiency of Software Engineers

This study employs the data-envelopment analysis (DEA)-Tobit regression approach to analyze data from a leading software engineering organization to gain insights regarding the role of various types of technical experience and task factors in the efficiency of personnel assigned to software tasks. “Efficiency” follows a holistic-view definition as the quality and productivity achieved from the overall personnel experience, and it is evaluated with DEA. Then, a Tobit regression model is employed to determine the effect that various types of technical experience and task factors have on the DEA efficiency scores. Although the DEA-Tobit technique has been applied to various areas within the management science and operations research fields, it has not yet been presented as a general evaluation tool within the software-engineering field to understand drivers of software quality and productivity. We demonstrate how DEA-Tobit fills a gap not addressed by commonly applied methods in the literature.

Integrated system to maximize efficiency in transit maintenance departments

Purpose – The purpose of this research is to show how an integrated system serves as an information support tool to assists maintenance managers to analyze data and evaluate alternatives in order to make better decisions that maximize efficiency in transit operations.Design/methodology/approach – A system which consists of a mathematical scheduling model that interacts with a forecasting model and repair time standards to allocate resources in maintenance departments is presented. Information was obtained from observations at three transit facilities in the Central Florida area; the model developed is tested using historical data of the maintenance jobs performed.Findings – Outputs obtained from testing have demonstrated reduction of operational costs, increased bus reliability, and increased efficiency in the tasks executed. Therefore, the present study aggregates value to transit organizations.Research limitations/implications – This research brings up alternatives of use of the resources in transit mai...

Innovative modules to introduce advance science and engineering concepts

STARS (Students, Teachers and Resources in the Sciences) is a National Science Foundation GK-12 funded project whose objective is to foster systemic change in elementary curricula and enrich math, science and long-term professional development of teachers. The program aims to decrease the current educational gap in science and math present in schools within the same school district, as reflected in the Florida comprehensive assessment test (FCAT). One challenging task is the development of new and innovative modules that introduce advanced science and engineering concepts to third, fourth and fifth grade students from diverse backgrounds. The modules have been designed by graduate fellows (resources) with knowledge in science, engineering, math and technology. This paper discusses the methodology for module development, formatting and design of the lessons, and implementation in the classroom. A discussion regarding the modules from the viewpoint of teachers, students and fellows is also provided.