High-Level Object Oriented Genetic Programming in Logistic Warehouse Optimization

Disertační práce je zaměřena na optimalizaci průběhu pracovních operací v logistických skladech a distribučních centrech. Hlavním cílem je optimalizovat procesy plánování, rozvrhování a odbavování. Jelikož jde o problém patřící do třídy složitosti NP-težký, je výpočetně velmi náročné nalézt optimální řešení. Motivací pro řešení této práce je vyplnění pomyslné mezery mezi metodami zkoumanými na vědecké a akademické půdě a metodami používanými v produkčních komerčních prostředích. Jádro optimalizačního algoritmu je založeno na základě genetického programování řízeného bezkontextovou gramatikou. Hlavním přínosem této práce je a) navrhnout nový optimalizační algoritmus, který respektuje následující optimalizační podmínky: celkový čas zpracování, využití zdrojů, a zahlcení skladových uliček, které může nastat během zpracování úkolů, b) analyzovat historická data z provozu skladu a vyvinout sadu testovacích příkladů, které mohou sloužit jako referenční výsledky pro další výzkum, a dále c) pokusit se předčit stanovené referenční výsledky dosažené kvalifikovaným a trénovaným operačním manažerem jednoho z největších skladů ve střední Evropě.This work is focused on the work-flow optimization in logistic warehouses and distribution centers. The main aim is to optimize process planning, scheduling, and dispatching. The problem is quite accented in recent years. The problem is of NP hard class of problems and where is very computationally demanding to find an optimal solution. The main motivation for solving this problem is to fill the gap between the new optimization methods developed by researchers in academic world and the methods used in business world. The core of the optimization algorithm is built on the genetic programming driven by the context-free grammar. The main contribution of the thesis is a) to propose a new optimization algorithm which respects the makespan, the utilization, and the congestions of aisles which may occur, b) to analyze historical operational data from warehouse and to develop the set of benchmarks which could serve as the reference baseline results for further research, and c) to try outperform the baseline results set by the skilled and trained operational manager of the one of the biggest warehouses in the middle Europe.

Tasks, cognitive agents, and KB-DSS in workflow and process management

The purpose of this paper is to propose a nonparametric interest rate term structure model and investigate its implications on term structure dynamics and prices of interest rate derivative securities. The nonparametric spot interest rate process is estimated from the observed short-term interest rates following a robust estimation procedure and the market price of interest rate risk is estimated as implied from the historical term structure data. That is, instead of imposing a priori restrictions on the model, data are allowed to speak for themselves, and at the same time the model retains a parsimonious structure and the computational tractability. The model is implemented using historical Canadian interest rate term structure data. The parametric models with closed form solutions for bond and bond option prices, namely the Vasicek (1977) and CIR (1985) models, are also estimated for comparison purpose. The empirical results not only provide strong evidence that the traditional spot interest rate models and market prices of interest rate risk are severely misspecified but also suggest that different model specifications have significant impact on term structure dynamics and prices of interest rate derivative securities.

Mercedes-Benz USA Labor Planning Dashboard

Mercedes-Benz USA specializes in producing high-quality vehicles that exceed customer expectations at a cost-effective rate. The company utilizes a labor planning dashboard that predicts the daily use of their lines at their part distribution centers by allocating their employees to different zones in inbound, outbound, or both. The supervisors manually input all the data to designate employees to various sections within those zones. Our team was tasked with improving and proposing an updated version of the labor planning dashboard by meeting their requirements while making it effective, responsive, and user-friendly. Through trial and error, the new labor planning dashboard combats these issues by eliminating an excessive amount of manual input and creates an automated dashboard by implementing a linear program solver known as an Assignment Problem

Integrating planning and scheduling in workflow domains

One of the main obstacles in applying AI planning techniques to real problems is the difficulty to model the domains. Usually, this requires that people that have developed the planning system carry out the modeling phase since the representation depends very much on a deep knowledge of the internal working of the planning tools. On some domains such as business process reengineering (BPR), there has already been work on the definition of languages that allow non-experts entering knowledge on processes into the tools. We propose here the use of one of such BPR languages to enter knowledge on the organisation processes to be used by planning tools. Then, planning tools can be used to semi-automatically generate business process models. As instances of this domain, we will use the workflow modeling tool SHAMASH, where we have exploded its object oriented structure to introduce the knowledge through its user-friendly interface and, using a translator transform it into predicate logic terms. After this conversion, real models can be automatically generated using a planner that integrates planning and scheduling, IPSS. We present results in a real workflow domain, the telephone installation (TI) domain.The SHAMASH project has being carried out in the course of the R&D project funded by the Esprit Program of the Commission of the European Communities as project number 25491. A complementary grant was given by the Spanish research commission, CICYT, under project number TIC98-1847-CE. We thank the partners of this project, who have originated and contributed to the ideas reported: UF (Unio´n Fenosa), SAGE (Software AG Espan˜ a), SEMA GROUP sae, UC3M (Universidad Carlos III de Madrid), WIP (Wirstchaft und infrastruktur & Co Planungs KG), and EDP (Electricidade de Portugal). We would specially like to thank all the UC3M team, the PLANET people and Paul Kearney (BT). Through talks with him we have outlined many ideas. This work has also been partially funded by grant MCyT TIC2002-04146-C05-05 and the UAH project PI2005/084.Publicad

Tasks, cognitive agents, and KB-DSS in workflow and process management

The purpose of this paper is to propose a nonparametric interest rate term structure model and investigate its implications on term structure dynamics and prices of interest rate derivative securities. The nonparametric spot interest rate process is estimated from the observed short-term interest rates following a robust estimation procedure and the market price of interest rate risk is estimated as implied from the historical term structure data. That is, instead of imposing a priori restrictions on the model, data are allowed to speak for themselves, and at the same time the model retains a parsimonious structure and the computational tractability. The model is implemented using historical Canadian interest rate term structure data. The parametric models with closed form solutions for bond and bond option prices, namely the Vasicek (1977) and CIR (1985) models, are also estimated for comparison purpose. The empirical results not only provide strong evidence that the traditional spot interest rate models and market prices of interest rate risk are severely misspecified but also suggest that different model specifications have significant impact on term structure dynamics and prices of interest rate derivative securities.

Design of an Automated Employee Scheduling System

Many retail stores, as well as other organizations that employ a multitude of part-time employees, rely on developing schedules frequently, since the availabilities of the employees as well as the needs of the business change often. This process is often performed on a weekly basis, and is complex and time-consuming. The schedule must typically satisfy numerous requirements, including business needs, legal restrictions, and employee availability constraints. As a result, errors are common, and employee time that could have been spent on improving sales or operations is instead consumed by the scheduling task. This project explores two solution methods for this problem. One method is the use of linear programming (LP) to develop an optimal schedule weekly. The other is the design and implementation of a scheduling system that uses a heuristic method. After developing both methods it was determined that while the LP approach may lead to optimal solutions, it was impractical due to high costs and complexity. The heuristic approach resulted in an automatic scheduling system that is easy to use, low cost, and flexible. The new scheduling system was evaluated and approved by future users

On the role of domain ontologies in the design of domain-specific visual modeling langages

Domain-Specific Visual Modeling Languages should provide notations and abstractions that suitably support problem solving in well-defined application domains. From their user’s perspective, the language’s modeling primitives must be intuitive and expressive enough in capturing all intended aspects of domain conceptualizations. Over the years formal and explicit representations of domain conceptualizations have been developed as domain ontologies. In this paper, we show how the design of these languages can benefit from conceptual tools developed by the ontology engineering community