The shift team formation problem in multi-shift manufacturing operations

This paper addresses the problem of assigning operators to teams that work in single-, two-, or three-day shift systems. The problem was motivated by, and illustrated with a case situation encountered in Dutch manufacturing industry. The problem addressed forms an extension of cell formation problems which are currently in the phase of addressing labor-related issues in cell design. A generalized goal problem formulation is presented to address multiple, conflicting objectives covering cross-training of workers, ensuring adequate levels of labor flexibility and minimizing labor-related costs. The proposed solution procedure consists of two phases. In the first phase, shift systems, in which applicable machines and the sizes of each shift team are identified. The next phase deals with assignment of operators to various teams and identification of specific cross-training needs for various workers. This phase involves the use of interactive goal programming. The methodology is illustrated by details from the case situation as well as a numerical example.

Lean implementation to improve scheduling for a multi-cell manufacturing facility

Includes bibliographical references

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.

Devising a Corporate Facility Location Strategy to Maximize Shareholder Wealth

Location decisions should consider all related impacts upon a firm’s shareholder wealth. Overall, firm cost savings available at alternative locations need to be carefully examined in addition to a location’s impact on corporate sales revenues. This article reviews relevant literature, discusses recent location decision considerations for several companies and empirically tests a model seeking to measure the impact corporate relocation decisions have upon shareholder wealth. In addition, a classification and listing of corporate location considerations is put forth to supplement the anecdotal illustrations discussed herein. Together these represent a "primer" for professionals and executives involved in corporate facility location decisions.

A Theory of Factor Allocation and Plant Size

In this paper we develop a theory of how factors interact at the plant level. The theory has implications for: (1) the micro foundations for capital skill complementarity (2) the relationship between factor allocation and plant size and (3) the effects of trade and growth on the skill premium. The theory is consistent with certain facts about factor allocation and factor price changes in the 19th and 20th centuries.

The impact of lean practices on inventory turnover

Lean manufacturing (LM) is currently enjoying its second heyday. Companies in several industries are implementing leanpractices to keep pace with the competition and achieve better results. In this article, we will concentrate on how companies can improve their inventoryturnover performance through the use ofleanpractices. According to our main proposition, firms that widely apply leanpractices have higher inventoryturnover than those that do not rely on LM. However, there may be significant differences in inventoryturnover even among lean manufacturers depending on their contingencies. Therefore, we also investigate how various contingency factors (production systems, order types, product types) influence theinventoryturnoveroflean manufacturers. We use cluster and correlation analysis to separate manufacturers based onthe extent of their leanness and to examine the effect of contingencies. We acquired the data from the International Manufacturing Strategy Survey (IMSS) in ISIC sectors 28–35

Integrated risk management in industries from the standpoint of safety and security

Manufacturing plants as well as robotic cells within their structures are complex systems, whose safety requires implementation of a wide ranging set of activities. These activities are mainly focused on risk minimization, with the aim of achieving acceptable levels of risk by means of appropriate measures. The human being, as a constituent of the man-machine-environment system, is in the centre of their attention. At the organizational level, risk management has to be integrated with strategic planning and managerial processes in the organization. This includes, inter alia, the need to effectively monitor and review the risk management processes. Comprehensive approach within the risk management process is based on interconnecting safety and security-related processes in the form of a generic approach

A theory of factor allocation and plant size

In this paper we develop a theory of how factors interact at the plant level. The theory has implications for (1) the micro foundations for capital-skill complementarity, (2) the relationship between factor allocation and plant size, and (3) the effects of trade and growth on the skill premium. The theory is consistent with certain facts about factor allocation and factor price changes in the 19th and 20th centuries.Human capital ; Labor supply

Bayesian Integration of Large Scale SNA Data Frameworks with an Application to Guatemala

We present a Bayesian estimation method applied to an extended set of national accounts data and estimates of approximately 2500 variables. The method is based on conventional national accounts frameworks as compiled by countries in Central America, in particular Guatemala, and on concepts that are defined in the international standards of the System of National Accounts. Identities between the variables are exactly satisfied by the estimates. The method uses ratios between the variables as Bayesian conditions, and introduces prior reliabilities of values of basic data and ratios as criteria to adjust these values in order to satisfy the conditions. The paper not only presents estimates and precisions, but also discusses alternative conditions and reliabilities, in order to test the impact of framework assumptions and carry out sensitivity analyses. These tests involve, among others, the impact on Bayesian estimates of limited annual availability of data, of very low reliabilities (close to non-availability) of price indices, of limited availability of important administrative and survey data, and also the impact of aggregation of the basic data. We introduce the concept of `tentative' estimates that are close to conventional national accounts estimates, in order to establish a close link between the Bayesian estimation approach and conventional national accounting.Macro accounts;system of national accounts;data frameworks;ratios;reliability;Bayesian estimation;sensitivity analysis;aggregation