Ph. D.

Submitted in fulfilment of the requirements of the degree of Masters of Technology in Cost and Management Accounting, Durban University of Technology, Durban, 2015. / The Stores Division reportedly found it very difficult to control inventories as well as executing roles and responsibilities allocated in the section. The aims of this study were to identify factors affecting the success of inventory control and to assess strategies used by the Stores Division of the eThekwini Municipality in Durban to control inventory stocks. In order to arrive at the deep structure underpinning inventory control, three theoretical frameworks were used, i.e., stock diffusion theory, application control theory and inventory control in theory and practice. This case study was census, descriptive, cross-sectional and predominantly quantitative in nature with only two open-ended questions. The 57 questionnaires were administered by members of staff at the Stores and Procurement Divisions of the eThekwini Municipality in Durban. Data were analysed using descriptive and inferential statistics and categorised according to themes. The IBM Statistical Package for Social Sciences (SPSS) version 21.0 was used to determine statistical results. The findings of the study revealed that employees lack proper training and education and that there is poor inventory control planning, lack of staff communication and lack of procurement time management when processing inventory orders. Respondents also indicated that there are no common strategies in place to control inventories. The study recommends that the Stores Division should consider the levels of staff qualifications, provide more staff training, and improve inventory control planning; communication; time management, and instigate innovative strategies in order to eradicate growing costs of inventory stocks. Moreover, the internal control processes need to be mapped according to the various roles identified.

L’interopérabilité entre applications d’entreprise est une problématique à multiples facettes. Pour y répondre, nous avons investigué l’alignement sémantique des connaissances sur les processus et objets métier supportés par les différentes applications d’entreprise. Ces connaissances sont souvent hétérogènes selon les métiers et implémentées de manières diverses, engendrant ainsi des conflits sémantiques dues aux différentes interprétations des acteurs. Nous étudions l’identification de correspondances et/ou de conflits sémantiques entre ces connaissances, plus particulièrement dans le domaine des applications de gestion d’atelier (MES – Manufacturing Execution System). Nous proposons une démarche de formalisation de ces connaissances sous la forme d’un référentiel standardisé conforme à la norme ISO 62264 : "le référentiel MES", ainsi qu’une démarche d’enrichissement de ce référentiel par alignements successifs avec d’autres normes et/ou référentiels. Nous définissons ainsi formellement un méta-modèle qui décrit les relations sémantiques entre les éléments des référentiels à aligner, et des règles de contrôle sémantique pour garder la cohérence du référentiel MES et sa conformité au standard. Enfin, nous présentons une démarche d’alignement des besoins client sur le référentiel MES pour aider à la mise en œuvre des applications d’entreprise. Ce travail de recherche a été réalisé dans le cadre d’un projet de Recherche et Développement soutenu par le cluster économique EDIT de la région Rhône-Alpes, et sur ses résultats ont été utilisés dans une nouvelle offre de « MES à la carte ». / Interoperability between enterprise applications is a multifaceted problem. In response, we have investigated the semantic alignment of business process and object knowledge supported by enterprise applications. This knowledge is heterogeneous across business and is implemented in different ways, generating semantic conflicts due to different interpretations of the actors. We study the identification of correspondences and/or conflicts between semantic knowledge, especially in the field of Manufacturing Execution System (MES). We propose an approach to formalize knowledge as a standardized repository ISO 62264 compliant: the "MES repository", and an approach to enhance the MES repository by successive alignments with other standards and/or repositories. Thus, we formally define a meta-model that describes the semantic relationships between elements of the aligned repositories, and semantic control rules to keep MES repository consistency and its ISO compliance. Finally, we present an approach to align customer needs with the MES repository, in order to assist the implementation of enterprise applications. This PhD thesis was conducted as part of a research and development project supported by the economic Cluster Edit (Rhône-Alpes, France), and its results have been used in the new proposal “on demand MES”.

Nous abordons le problème de la gestion des chaînes logistiques dans le cadre d’une démarche RSE (Responsabilité Sociale des Entreprises). Nous proposons une approche intégrée qui permet d’opérationnaliser l’évaluation de la performance suivant les dimensions économique, environnementale et sociale aux niveaux de décisions stratégique, tactique et opérationnel. Nous déclinons notre approche aux niveaux stratégique et tactique, pour le problème d’internalisation/externalisation « durable » des activités de la chaîne de valeur d’une part (décision stratégique), et pour le problème de la planification stratégique-tactique durable de la chaîne logistique, d’autre part. Nous réalisons dans le premier cas une analyse de la valeur que nous couplons à l’évaluation de la performance en utilisant une méthode d’aide à la décision multicritères agrégative : l’AHP (Analytical Hierarchy Process). Dans le second cas, nous formulons le problème comme un programme mathématique multi-objectifs que nous résolvons sur la base d’un cas réaliste issu de l’industrie canadienne du bois d’œuvre. Nous obtenons, à l’issue de la résolution mathématique, plusieurs solutions de compromis (optimums de Pareto) présentant différents niveaux de performances économique, environnementale et sociale, permettant au décideur de choisir la solution qui correspond le mieux à sa stratégie RSE. Cette application illustre la méthode proposée et met en avant la valeur pratique de notre approche. / We address the problem of supply chain management in the context of CSR (Corporate Social Responsibility). We propose an integrated approach allowing the operationalization of the economic, environmental and social performances at the strategic, tactical and operational decision levels of the supply chain. In particular, we apply our approach to the strategic and tactical levels, for the problem of sustainable insourcing/outsourcing of the activities of the value chain on the one hand (strategic decision), and for the problem of the strategic-tactical planning of a sustainable supply chain on the other hand. In the former case, we combine value analysis with performance measurement using AHP method (Analytical Hierarchy Process), an aggregative multi-criteria technique. In the latter, we develop a multi-objective mathematical program that we apply to a realistic case inspired by the Canadian lumber industry. After solving the problem, we obtain a multitude of compromise solutions (Pareto optimums) presenting different performance levels following the economic, environmental and social dimensions, allowing the decision maker to choose the solution that reflects best his/her CSR strategy. This application illustrates the proposed method and allows us to assess the practical value of our approach.

Submitted by Patrícia Valim Labres de Freitas (patricial) on 2016-04-01T17:52:53Z No. of bitstreams: 1 Thiago Antonio Souza.pdf: 1549573 bytes, checksum: 50bb2fe3750913e23e67747ffad33743 (MD5) / Made available in DSpace on 2016-04-01T17:52:53Z (GMT). No. of bitstreams: 1 Thiago Antonio Souza.pdf: 1549573 bytes, checksum: 50bb2fe3750913e23e67747ffad33743 (MD5) Previous issue date: 2015-12-23 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPQ – Conselho Nacional de Desenvolvimento Científico e Tecnológico / Hospitais brasileiros tipicamente convivem com um desnivelamento entre capacidade e demanda. Os subsistemas público e privado são incapazes de coordenar situações de falta e excesso de capacidade identificados, de forma concomitante, em suas respectivas estruturas. Custos tornam-se um elemento focal em ambos os casos, quer visando qualidade e segurança quer visando incremento de capacidade, enfocando áreas chave do serviço hospitalar: serviços cirúrgicos, de internação, de emergência e de diagnóstico. O Lean Healthcare, neste contexto, se torna uma filosofia possível para a mudança organizacional dos processos hospitalares visando o incremento de sua eficiência. Este estudo discute a aplicação de conceitos do Lean Healthcare em serviços cirúrgicos, com base em evidências coletadas de três estudos realizados integradamente em um hospital universitário de grande porte, pertencente ao subsistema de saúde público brasileiro. O primeiro estudo enfoca a análise de eficiência do centro cirúrgico, propondo e aplicando o indicador Operating Room Effectiveness (ORE). O segundo, analisa e propõe formas de nivelar a produção (Heijunka) de cirurgias de diferentes demandas competindo pelo mesmo centro cirúrgico, em um contexto de capacidade inferior à demanda. O terceiro estudo desenvolve o conceito de Planejamento, Programação e Controle do Fluxo de Pacientes (PPCFP), com vistas ao planejamento integrado de consultas, cirurgias, pré-operatórios e aquisição de materiais. A aplicação dos modelos conceituais propostos revela potenciais vantagens, ainda a serem estudadas em amplitude e longitude como alternativa para outras organizações do setor. Como resultados locais, além do aporte de conceitos de Engenharia de Produção aplicada ao contexto de saúde, foram identificados: ganho operacional médio de 12% de eficiência nas salas de cirurgia; redução em 40% do tempo médio de espera para cirurgias eletivas; redução média de filas para consultas em 50%; melhor planejamento e controle de eficiência e produção; e economia de cerca de R$ 5.000.000,00 resultante dos três casos. / Brazilian hospitals typically work with a depression between capacity and demand. The public and private subsystems are unable to coordinate situations of shortage and excess capacity identified in their respective structures, concomitantly. Costs become a focal element in both cases, aiming to quality and safety or to increase capacity, focusing on key areas of hospital service: surgical services, admission, emergency and diagnostic. In this context, Lean Healthcare becomes an attractive philosophy for organizational change of hospital processes aiming at increasing its efficiency. This study discusses the application of Lean Healthcare concepts in surgical services, based on evidence collected from three studies integrally in a large University Hospital, part of the Brazilian public health subsystem. The first study focuses on the operating room efficiency analysis, proposing and applying the indicator Operating Room Effectiveness (ORE). The second study analyzes and proposes alternatives to level the production of surgeries (Heijunka) of different brands, competing for the same operating room, at a low capacity context. The third study develops the concept of Planning, Programming and Control of Patient Flow (PPCPF), to establish integrated planning consultations, surgeries, preoperative and acquisition of materials. The application of the proposed conceptual models reveals potential advantages, yet to be studied in amplitude and longitude as an alternative to other industry organizations. As local gains, in addition to the approximation of Industrial Engineering concepts to the health context, it have been identified: 12% increase in the surgical center’s average efficiency; 40% reduction in the average waiting time for elective surgery; 50% reduction in the number of queued consultations; better planning and control efficiency and production; and savings of about R$ 5,000,000.00 resulting from the three cases.

[pt] Muitas organizações de produção por projeto (i.e., também conhecidas pela sigla inglesa ETO, engineering-to-order) são sistemas de produção multi-projeto em que o planejamento da capacidade, na fase de negociação de novos pedidos, é de suma importância. A literatura acadêmica, nesta área, apresenta uma lacuna entre teoria e prática em função da falta de estudos sobre a aplicação de ferramentas de apoio à tomada de decisão para resolver problemas de planejamento de capacidade em ambientes reais de produção ETO. Dentro deste contexto, o objetivo deste trabalho é desenvolver uma solução para o planejamento tático da capacidade produtiva, apoiando essa fase de negociação, numa organização multi-projeto fabricante de equipamentos especiais sob encomenda. Este estudo envolve o desenvolvimento de modelos de programação linear inteira mista e sua aplicação para resolver problemas de planejamento da produção na organização estudada. Quanto às contribuições teóricas desta tese, é apresentado um modelo determinístico em que são consideradas questões de modelagem não totalmente exploradas em outros estudos ou que tem de ser adaptadas às especificidades do contexto estudado, como a representação da capacidade extra, de processos com múltiplos estágios e a relação de precedência entre as atividades. Além disso, um modelo de otimização robusta, baseado na abordagem proposta por Bertsimas e Sim (2004), estende esse modelo determinístico, considerando incertezas relativas aos tempos de processamento das atividades. Os modelos foram alimentados com dados do mundo real e executados para fins de validação de sua utilidade para resolver o problema de planejamento em questão. Cenários alternativos também foram gerados para apoiar a tomada de decisão dos gestores dessa empresa na fase de negociação de novos pedidos. Com relação às implicações práticas, para a equipe de planejamento da empresa, a solução proposta aprimora o processo de tomada de decisão no que tange o planejamento tático da capacidade produtiva. A solução, além de resolver algumas deficiências do método de planejamento atual da empresa, fornece informações mais detalhadas sobre o problema, permite a intervenção do gestor na construção dos planos de capacidade e incorpora dados relativos à variabilidade nos tempos de processamento permitindo assim uma postura pró-ativa mediante as incertezas. Resultados empíricos mostram que, com um aumento relativamente pequeno no custo (0.02 porcento), um componente deveria ser preferencialmente produzido na própria empresa (ao invés de ser subcontratado). Além disso, com um aumento de 0.8 porcento no custo (o que inclui a contratação de 21 porcento a mais de mão-de-obra direta), a probabilidade de violação dos planos de produção é reduzida de 90 porcento para 15 porcento, representando um plano mais estável e protegido contra incertezas. Do ponto de vista acadêmico, esta pesquisa acrescenta evidências empíricas para enriquecer a literatura existente, uma vez que não só apresenta um caso real, mas também destaca questões que devem ser consideradas e gerenciadas em um contexto do mundo real para que se possa desenvolver e implementar técnicas adequadas para lidar com o problema de planejamento estudado. / [en] Many engineering-to-order (ETO) organizations are multi-project capacity-driven production systems in which capacity planning is of major importance in the order acceptance phase. The academic literature, in this area, presents a research-practice gap with a lack of studies on the application of decision support tools to address capacity planning problems in real-world ETO settings. Within this context, the goal of this thesis is to develop a tactical capacity planning solution to support the order acceptance phase of a real-world multi-project organization that produces customised equipments on the basis of ETO policy. This research study lays in the development of mixed integer linear programming models and their practical application to solve production planning problems in the studied organization. As for the theoretical contributions of this thesis, first a deterministic model is presented in which modelling issues that are either not entirely explored in other studies or that have to be adapted to the specificities of the studied setting are taken into account. Moreover, a robust optimization model extends the former model by considering uncertainties of the planning problem. The models were fed with real-world data and solved in order to check whether they actually reflect the planning problem. Furthermore, alternative scenarios were also generated to assist the management board in the order acceptance phase. As for practical implications, for the company s manufacturing planning team, the proposed solution enhanced the decision-making process regarding tactical capacity planning, addressing different shortcomings of the company s current planning method. Empirical results suggest that with a slight increase in cost (0.02 percent) a part component should be processed in-house instead of being outsourced and that with a 0.8 percent increas in cost (which includes hiring 21 percent more personnel) the probability of violating the production plans decreases from 90 percent to 15 percent, representing a much more stable (protected against uncertainty) situation. From an academic perspective, this research adds empirical evidence to enrich the existing literature, as it not only presents a real case application, but also highlights issues that must be considered and managed in a real-world context in order to develop and implement appropriate techniques to cope with the aforementioned planning problem.

O setor industrial produtor de papel e celulose tem aumentado sua relevância comercial nas últimas décadas devido à demanda constantemente crescente. O aumento na competitividade do setor gerado pela economia globalizada e a dificuldade de desenvolvimento de bons planos de produção em ambientes produtivos cada vez mais complexos têm motivado a pesquisa por novas e efetivas ferramentas de auxílio à tomada de decisão. Considerando estas dificuldades, abordamos neste trabalho o problema de dimensionamento e sequenciamento de lotes com foco em empresas com processo integrado de produção de celulose e de papel. Trata-se de um problema de planejamento de médio a curto prazo, geralmente com maior enfoque no curto prazo por considerar o planejamento detalhado da produção em horizontes de planejamento que não superam 30 dias. No processo integrado de celulose e papel, foram consideradas as decisões de produção do digestor, evaporador, caldeira de recuperação e de múltiplas máquinas produtoras de papel, além do controle de estoque de produtos intermediários e finais. Modelos matemáticos da literatura foram modificados e estendidos para incorporar características adicionais do problema como, por exemplo, processos com múltiplas máquinas de papel. Além disso, foram desenvolvidas heurísticas construtivas, heurísticas de melhoria, abordagens de solução híbridas baseadas em algoritmos genéticos combinadas com ferramentas comerciais de solução exata, além de combinações entre os métodos. As abordagens desenvolvidas foram testadas computacionalmente e as melhores combinações de métodos foram definidas. De forma geral, os resultados dessas abordagens foram superiores aos obtidos por ferramentas de solução comerciais puras. Ademais, a variação proposta da heurística de melhoria fixe-e-otimize com mudanças na função objetivo se destacou com relação aos demais métodos, obtendo os melhores resultados, independentemente da qualidade da solução inicial utilizada. As principais contribuições desta tese são a apresentação de modelos matemáticos para representar apropriadamente o problema estudado, e o desenvolvimento de métodos de solução efetivos para resolver o problema. / The pulp and paper industry has been increasing the commercial importance in recent decades due to the constant growing demand. The increasing competitiveness of this sector generated by the globalized economy and the difficulty to develop good production plans in complex production environments have motivated the search for new and effective decision support systems. Given these difficulties, in this thesis we address the lot sizing and scheduling problem focused on integrated pulp and paper mills. This is a problem of medium to short term planning, generally more focused on the short term as it covers detailed production schedules in planning horizons which do not exceed 30 days. In these integrated pulp and paper process the production decisions of digester, evaporator, recovery boiler and multiple paper machines are considered, apart from the inventory control of intermediate and final products. Mathematical models known in the literature were modified and extended to incorporate additional features of the problem, such as processes with multiple paper machines. In addition, constructive and improvement heuristics, and hybrid methods based on genetic algorithms combined with a commercial solver were developed, as well as combinations of these solution approaches. The methods developed were computationally tested and the best combinations of methods were defined. Overall, the results of these methods were superior to the solutions obtained by pure commercial solvers. Moreover, the alternative variation proposed of the improvement heuristic fix-and-optimize with exchanges in the objective function surpassed the other methods, obtaining the best results, regardless of the quality of the initial solution used. The main contribution of this thesis are the presentation of mathematical models that appropriately represents the problem under study, and the development of effective solution methods to deal with the problem.

To make a difference among the energy intensive process industries, this dissertation addresses production planning and supply chain planning problems related to industrial energy management issues. The energy issue is turning more and more important from different angles, involving price as well as environmental problems due to climate change leading to political pressure on all energy users. The process industry sector is one of the largest users of energy, and thus important to analyse. Process industries are also capital intensive and operate on large and expensive process equipment, making it imperative to plan their production well in order to reach preferable capacity utilisation. Therefore this dissertation strives to locate the most important energy management issues for the long term profitability of process industries, and investigates the  symbiotic effects of including energy issues in production and supply chain planning. Three different studies at three case companies are carried out, analysed, and presented in five papers. The cases represent the process industry sectors: chemicals, pulp, and steel. Both qualitative case study methodologies as well as quantitative mathematical modelling and optimisation approaches have been practiced. The research questions are analysed from both an energy system and from a production process point of view, separately as well as combined. Energy is somewhat considered to be the main workforce for process industries and this dissertation exemplifies some of its most important dimensions in this context. Several prerequisites for putting energy management on the strategic agenda are located in a specialty chemical industry where the importance of introducing a strategic perspective on energy, the way energy is used, and the possibilities of increasing alternative revenue from utilising by- and/or co-products differently are pinpointed. Approaches for including energy issues in planning processes are also suggested in terms of a MILP model for the entire supply chain of a pulp company, including decisions on purchase and transportation of raw maerials, production allocation, energy mix, and distribution. Another example is presented based on the perspectives of economics of scale and lot sizing through economic order quantity principles in a steel company. By using real company data, energy smart approaches in planning and scheduling are developed with respect to the most important intersections between the production processes and their supporting energy system. The accumulated resource intensity and embedded energy could, and probably should, hence be more fairly  reflected in the product price. The research finally shows some possible impact with including energy issues in a production and supply chain planning model. By planning differently, production prioritisations can be done, and it is not only possible without any large investments, but also prosperous with savings on both energy and money within reach. To conclude, planning of production and supply chain has either a direct or an indirect impact on the energy cost-effectiveness of a company. This dissertation argues that such impact also exists in its mutual form, and is very important when the energy issues are large enough, as they often are in the energy intensive process industry sector. Decision makers should thus beware of the short end of the stick that might be  devastating in the long run, but also aware of all the possibilities that can bring success and prosperity when the future begins.

Tillgänglighet är ett stort problem inom svensk sjukvård. Produktionsplanering skulle kunna bidra till att korta ned ledtider och på så sätt öka tillgängligheten, men det saknas kunskap om hur detta påverkar arbetsmiljön för personalen. Ett förbättringsarbete genomfördes på en psykiatrisk öppenvårdsmottagning med syfte att med hjälp av produktionsplanering korta ledtiden mellan två steg i den diagnostiska processen. Förändringen innebar att patienterna fick möjlighet att boka tid till nästa besök direkt i samband med det första besöket. Arbetet utgick från Nolans förbättringsmodell. En studie av förbättringsarbetet, med induktiv ansats, genomfördes med syftet att undersöka hur denna förändring påverkade arbetsmiljön. Intervjuer genomfördes med berörda medarbetare och analyserades med innehållsanalys. Förbättringsarbetet resulterade i att ledtiden mer än halverades, med befintliga resurser. Medarbetarnas delaktighet bedömdes ha haft betydelse för det lyckade resultatet. Studien visade att arbetsmiljön ej påverkades negativt, utan tvärtom att arbetstillfredsställelsen ökade. Viktiga förklaringar till detta var att medarbetarna upplevde det som tillfredsställande att kunna erbjuda patienterna en snar tid för nästa besök, att förändringen ledde till minskad administration och att medarbetarna fortfarande hade kontroll över sina tidböcker. Slutsatsen är att det är möjligt att öka produktionen med hjälp av produktionsplanering utan att det får negativa effekter för arbetsmiljön. / Accessibility is a major problem in Swedish healthcare. Production planning could help to shorten waiting times and improve accessibility, but there is insufficient knowledge of how this affects the working environment. An improvement project was initiated with the purpose to shorten the lead time between two steps in the diagnostic process at a psychiatric outpatient clinic, with the help of production planning. The change meant that patients were offered to book a time for the next visit during the first visit. A study of the project was initiated to investigate how the change affected the working environment. Interviews were conducted and analysed with content analysis. The improvement project led to lead times being more than halved. Employee participation was important for reaching this result. The study showed that the working environment was not adversely affected, on the contrary job satisfaction increased. Explanations for this was the satisfaction of being able to offer patients to book a new visit directly, less time spent on administrative tasks and staff retaining significant control over their schedule. The conclusion is that it is possible to increase production by means of production planning without this having negative effects on the working environment.

Objective of the present work is the deep study of the manufacturing systems in terms of energy efficiency. Manufacturing enterprises have to reduce energy consumption for both cost saving and environmental friendliness, finding new ways to produce more with less. As a first step, clear definitions for the energy efficiency are provided, in order to successfully include this significant key performance indicator into the manufacturing decision-making attributes. These definitions are used in order to develop a generalized and holistic approach towards manufacturing energy efficiency. The basic element of the approach is the division of energy efficiency definition and study into four manufacturing levels, namely process, machine, production line, and factory. Process-level definitions are provided for the majority of manufacturing processes. A machine-level study indicates and solves difficulties, generated by the workpiece geometry, and points out the interaction with the process level through factors, such as the process time. Moreover, machine tool peripherals are responsible for a significant portion of the consumed energy. Classification of the machine peripherals, based on the dependence of their consumption on process variables, is required. Studies made on the production line and factory levels show that energy efficiency, at these levels, is heavily dependent on production planning and scheduling and can be improved through the appropriate utilization of machines, with the inclusion of shutdown and eco-modes. All the methods developed for each of the manufacturing levels are verified with appropriate case studies. Moreover, a holistic case study is presented, showing that many of the difficulties towards the optimization of energy efficiency can be dealt with successfully, using the proposed generalized approach. The implementation of the method in a software platform is presented. The tool is industrially evaluated using three case studies from three different industrial sectors (i.e. aeronautics, automotive and household). The evaluation of the presented case studies clearly reveals the usefulness and efficiency of the suggested approach validating its applicability to real industrial environments. This prototype information technology decision support tool can assist the manufacturing sector towards energy and eco-efficiency, within the context of a multi-objective optimization procedure, incorporating traditional metrics (i.e. time, cost, flexibility and quality), interacting with the machine monitoring systems. / Αντικείμενο της παρούσας διατριβής είναι η μελέτη της ενεργειακής αποδοτικότητας των συστημάτων παραγωγής. Η αύξηση της ενεργειακής αποδοτικότητας, προσφέρει μείωση του κόστους παραγωγής και των βλαβερών επιπτώσεων στο περιβάλλον. Αρχικά, παρέχονται ορισμοί για την ενεργειακή αποδοτικότητα, προκειμένου να συμπεριληφθεί και αυτός o σημαντικός δείκτης στα συνήθη κριτήρια λήψης αποφάσεων (δηλαδή το χρόνο, το κόστος, την ευελιξία και την ποιότητα). Οι ορισμοί αυτοί χρησιμοποιούνται για την ανάπτυξη μιας γενικευμένης και ολιστικής μεθοδολογίας ως προς την αύξηση της ενεργειακής αποδοτικότητας στα συστήματα παραγωγής. Το βασικό στοιχείο της μεθόδου είναι ο διαχωρισμός του ορισμού της ενεργειακής απόδοσης και της μελέτης του σε τέσσερα ιεραρχικά επίπεδα, ξεκινώντας από την διεργασία, τη εργαλειομηχανή, τη γραμμή παραγωγής και την μονάδα παραγωγής. Ορισμοί στο επίπεδο της διεργασίας, παρέχονται για την πλειονότητα των κατηγοριών των μηχανουργικών διεργασιών. Στο επίπεδο της εργαλειομηχανής μελετώνται οι διαφορές που προκύπτουν από την γεωμετρία του προϊόντος, και επισημαίνονται οι αλληλεπιδράσεις με το επίπεδο της διεργασίας μέσω παραγόντων, όπως ο χρόνος διεργασίας. Επιπλέον, αποδεικνύεται ότι τα περιφερειακά των εργαλειομηχανών είναι υπεύθυνα για ένα σημαντικό μέρος της καταναλισκόμενης ενέργειας. H ενεργειακή κατάταξη των περιφερειακών των εργαλειομηχανών, με βάση την εξάρτηση της κατανάλωσης τους από παραμέτρους της διεργασίας, είναι απαραίτητη. Μελέτες στα επίπεδο της γραμμής παραγωγής και της μονάδας παραγωγής, δείχνουν ότι η ενεργειακή αποδοτικότητα εξαρτάται σε μεγάλο βαθμό από τον χρονοπρογραμματισμό της παραγωγής και μπορεί να βελτιωθεί με την κατάλληλη αξιοποίηση των εργαλειομηχανών, συμπεριλαβαίνοντας τον τερματισμό της λειτουργιάς αυτών ή τη χρήση οικολογικών λειτουργιών (eco-modes). Όλες οι μέθοδοι που αναπτύχθηκαν για τα επίπεδα παραγωγής επαληθεύονται με μελέτες εφαρμογής. Για την υλοποίηση της μεθόδου αναπτύχθηκε λογισμικό το οποίο αξιολογήθηκε σε τρεις διαφορετικούς βιομηχανικούς τομείς με σημαντικά αποτελέσματα. Αυτό το πρωτότυπο εργαλείο υποστήριξης αποφάσεων μπορεί να βοηθήσει στην μείωση της ενεργειακής κατανάλωσης χρησιμοποιώντας πολύ-παραγοντική βελτιστοποίηση, λαμβάνοντας υπόψιν την ενεργειακή αποδοτικότητα μαζί με τα συνήθη κριτήρια λήψης αποφάσεων αλληλοεπιδρώντας με τα συστήματα παρακολούθησης των εργαλειομηχανών.