Ilias P. Tatsiopoulos

National Technical University of Athens | NTUA · School of Mechanical Engineering

The major objective of this paper is to analyze the most widely used techniques for risk assessment and to discuss their applicability as decision support tools for military operations. These are the qualitative and the quantitative risk analyses, which are commonly used for handling uncertainty in project management. Initially, the main processes...

A fuel based optimality approach is to be presented, adapted for large retrofitting projects in the electricity market. The case study focuses on existing lignite power plants that may switch their fuel to natural gas and from that point on they may either switch back to lignite or retain natural gas or routinely switch between these two alternativ...

The Job-shop Scheduling Problem (JSSP) is considered one of the most difficult NP-hard problems. Numerous studies in the past have shown that as exact methods for the problem solution are intractable, even for small problem sizes, efficient heuristic algorithms must achieve a good balance between the well-known themes of exploitation and exploratio...

Municipal Solid Waste (MSW) disposal has been a controversial issue in many countries over the past years, due to disagreement among the various stakeholders on the waste management policies and technologies to be adopted. One of the ways of treating/disposing MSW is energy recovery, as waste is considered to contain a considerable amount of bio-wa...

As oil prices have risen dramatically lately, many people explore alternative ways of heating their residences and businesses in order to reduce the respective cost. One of the options usually considered nowadays is biomass, especially in rural areas with significant local biomass availability. This work focuses on comparing two different biomass e...

In today’s business environment, supply chains involve a number of autonomous organizations. The nature of supply chain processes with inter-organizational activities, involving different enterprises, calls for their design, analysis, control and evaluation in a well-designed and structured manner. The increasing importance of business processes in...

In today’s business environment, supply chains involve a number of autonomous organizations. The nature of supply chain processes with inter-organizational activities, involving different enterprises, calls for their design, analysis, control and evaluation in a well-designed and structured manner. The increasing importance of business processes in...

Supply Chain Management (SCM) has been in the epicenter of numerous research efforts for, at least, the last two decades. One of the most prominent issues identified in literature, directly related with Supply Chain Integration and Collaboration, is information sharing between supply chain entities, especially for planning and monitoring purposes....

This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost-benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as we...

One of the most widely used methods for investment assessment is the internal rate of return (IRR) that is based on the discounted cash flow analysis. Furthermore, the quantitative risk analysis technique is commonly used during the project's initial stage, simply by weighting the financial performance with the incurred risks. Herein, we introduce...

The fair division of a surplus is one of the most widely examined problems. This paper focuses on bargaining problems with fixed disagreement payoffs where risk-neutral agents have reached an agreement that is the Nash-bargaining solution (NBS). We consider a stochastic environment, in which the overall return consists of multiple pies with uncerta...

Proofs of Theorems and Propositions. (DOC)

This paper focuses on the initial assessment of wastewater treatment (WT) projects through Public Private Partnerships (PPPs). Due to the fact that the initial investment of a PPP-type WT project is too high and can be financed by both the public and private sectors, crucial during the project's feasibility stage is to estimate the partners' fundin...

Risk assessment is one of the most critical procedures for the evaluation of environmental projects. Over the last decades, there are several methods and techniques developed in the risk assessment literature establishing the quantitative risk analysis of waste treatment projects. Herein, the authors focus on the correlation between the financial s...

The issue of Municipal Solid Waste (MSW) management is an ever increasing problem for all countries. Developed countries face the problem of dealing with very large amounts of MSW per capita, forcing them to develop new technologies and systems. On the other hand, countries with developing or transitional economies may generate lower amounts of MSW...

This paper examines the feasibility stage of Public Private Partnerships (PPPs) and specifically the evaluation of the public sector's contribution in the project's funding scheme. We focus on those PPP projects, where the initial investment is funded by both public and private parts and revenues are shared between the two. Generally, a basic step...

This paper examines the evaluation of a waste management project's alternatives through a quantitative risk analysis. Cost benefit analysis is a widely used method, in which the investments are mainly assessed through the calculation of their evaluation indicators, namely benefit/cost (B/C) ratios, as well as the quantification of their financial,...

In this paper we focus on the coordination of multiagents through a revenue-cost-sharing mechanism. We consider a grand-coalition consisting of finite agents, who undertake part of the costs individually, while the remaining costs C and the total revenues R are shared between them with a revenue-cost-sharing contract. We introduce a novel approach...

This paper focuses on the decentralized systems that use the revenue-sharing and cost-sharing contracts as coordination mechanisms. We consider a grand-coalition N with finite players, who agree to cooperate by undertaking part of the system's cost individually, while the remaining costs C and revenues R are shared properly, in order to allocate th...

Municipal solid waste management is one of the most pressing issues of today's societies as the consequences of growing economies in waste generation have serious effects on the environment. These effects are even more difficult to tackle in remote areas such as islands or mountainous areas, both types of which are dominant in the Greek topography....

This paper examines the initial budget estimation process for the implementation of waste treatment projects through Public-Private Partnership (PPPs) in Greece. The study, having as strong theoretical foundation the project’s financial analysis that is included in the cost benefit analysis methodology, evaluates the financial sustainability of a w...

Power production was traditionally dominated by monopolies. After a long period of research and organisational advances in international level, electricity markets have been deregulated allowing customers to choose their provider and new producers to compete the former Public Power Companies. Vast changes have been made in the European legal framew...

Tunnels have improved the connection of regions within the European Commission (EC) and have been used lately as a catalyst for economic development of previously isolated regions. However, the increasing number of these important infrastructures is raising upfront an endogenous problem, which is the severity of accidents that may occur. These risk...

Waste management has become a great social concern for modern societies. Landfill emissions have been identified among the major contributors of global warming and climate changes with significant impact in national economies. The energy industry constitutes an additional greenhouse gas emitter, while at the same time it is characterized by signifi...

The scope of this work is to investigate the effect that various scenarios for emission allowance price evolution may have on the future electricity generation mix of Greece. The renewable energy generation targets are taken into consideration as a constraint of the system, and the learning rates of the various technologies are included in the calc...

Tunnels are regarded as one of the most important infrastructures in Europe, as they may improve the connection of regions and aid economic development through facilitating the transportation of people and goods. In order to achieve a minimum acceptable level of safety, the EC issued Directive 2004/54/EC, which describes specific safety measures th...

A systematic impact assessment of stochastic interest and inflation rates on the analysis of energy investments is presented. A real-options algorithm has been created for this task. Constant interest rates incorporating high risk premium have been extensively used for economic calculations, within the framework of traditional direct cash flow meth...

This paper examines the assessment and funding rate estimation process for the implementation of wastewater treatment (WT) projects through Public Private Partnerships (PPPs). The study, having as strong theoretical foundation the Cost Benefit Analysis (CBA) methodology and the quantitative Value for Money (VfM) assessment process, develops a new a...

This work investigates and compares energy-related, private business strategies, potentially interesting for investors willing to exploit either local biomass sources or strategic conventional fuels. Two distinct fuels and related power-production technologies are compared as a case study, in terms of economic efficiency: the biomass of cotton stal...

In this paper, the optimum location of a bioenergy generation facility for district energy applications is sought. A bioenergy facility usually belongs to a wider system, therefore a holistic approach is adopted to define the location that optimizes the system-wide operational and investment costs. A hybrid optimization method is employed to overco...

This paper deals with risk analysis in cut and cover road tunnels. The research question explored is whether dividing a long tunnel into shorter sections would affect the safety when dangerous goods are allowed through the tunnel. In order to conclude the OECD/PIARC QRA Model quantitative risk analysis tool was used. Initial findings reveal that th...

On deciding for the most appropriate investment when capital restrictions exist, investors define their alternatives and analyze each one of them. Traditionally, the definition, appraisal and analysis stages are treated separately. Herein, an innovative holistic method is proposed for bridging these stages. Within this method, investment attributes...

Biomass is a renewable energy source with increasing importance. The larger fraction of cost in biomass energy generation originates from the logistics operations. A major issue concerning biomass logistics is its storage, especially when it is characterized by seasonal availability. The biomass energy exploitation literature has rarely investigate...

Biomass cogeneration is widely used for district heating applications in central and northern Europe. Biomass trigeneration on the other hand, constitutes an innovative renewable energy application. In this work, an approved United Nations Framework Convention on Climate Change baseline methodology has been extended to allow the examination of biom...

The use of biomass for decentralized energy production has undergone a significant development the last years. The fact that this fuel is CO2-free provides many advantages in European and world aims for sustainable energy sources. Biomass trigeneration is a relatively new concept, which has the potential to improve the bioenergy economics for areas...

In this paper, a decision support system (DSS) for multi-biomass energy conversion applications is presented. The system in question aims at supporting an investor by thoroughly assessing an investment in locally existing multi-biomass exploitation for tri-generation applications (electricity, heating and cooling), in a given area. The approach fol...

Although many research efforts have concluded to effective methods for solving the theoretical Job Shop Scheduling Problem (JSSP), only few of them have been applied to practical decision support tools. This paper presents an algorithmic framework employed in a Decision Support System (DSS) for production planning and scheduling purposes, which has...

While economy and ecology ought to share the same values and targets, as their common 'eco' prefix indicates, reality tends to be somehow different. Economic growth and environmental protection seem to be noncompatible, both in methods and in results. In many cases, for example, investments trigger actions that operate competitively to the wealth o...

The aim of this paper is to present the implementation of a tailor made production planning and control (PPC) system for a Greek small-to-medium (SME) enterprise, which utilizes advanced production planning methods as well as recent achievements of IT technology. The methodology followed, includes a staged system development approach that spans acr...

The purpose of this paper is to thoroughly present the findings of a research project undertaken by the authors regarding the development of a detailed production scheduling system and its implementation in a Greek metal forming industry. The proposed system, entitled “eGantt”, was developed through the scope of a decision support tool and was aime...

The aim of this paper is to supply an overview of the classical and modern algorithms developed for the JSSP (Job Shop Scheduling Problem) coupled with a critique on their strengths and weaknesses. In this respect, first it is deemed essential to provide an elaborate definition of the deterministic and the dynamic JSSP as well as their various opti...

Η παρούσα εργασία παρουσιάζει μία μεθοδολογική προσέγγιση για τον ανασχεδιασμό ενός συστήματος αναπλήρωσης των αποθεμάτων για το σύνολο των υλικών (ανταλλακτικών συντήρησης ή αναλωσίμων υλικών) που συνήθως διαχειρίζεται ένας μεγάλος οργανισμός του δημοσίου ή ιδιωτικού τομέα που διαθέτει ακριβό και πολυάριθμο εξοπλισμό, ο οποίος παράλληλα αποτελεί σ...

Lately, traditional forecasting methods have been depicted as inferior to newer ones which are attempting to simulate the human decision making process. However, this goal might even be impossible to achieve. This paper introduces an inverse approach to the forecasting problem. The typical process of attempting to subtractively model the expert's k...

This study pinpoints the absence of any literature on the vendor's process of analysing, designing, developing and delivering the Enterprise Resource Planning (ERP) system and identifies the need for a selection methodology that includes a targeted set of criteria covering these areas. We aim to address this issue by defining the term ERP Supply Ch...

Knowledge and its management have been respectively accepted as a critical resource and a core business competency. Despite that literature proves the existence of a gap between the theoretical considerations of Knowledge Management (KM) and their efficient application. Such lacking, we argue, derives from the missing link between a framework of Kn...

The modern competitive markets rely heavily on the concept of globalization. In this respect, the virtual enterprise approach and a holistic view of an enterprise's supply chain come into play. Nowadays, a company is as reliable and efficient as the weakest link in its supply chain. An unhampered product and information flow among the supply chain...

Over the past decade, KM is receiving increasing attention from researchers and practitioners alike. However, a well-integrated and holistic framework that would unify the discipline and guide practice is currently missing. In an effort to address the identified gap, we propose a holistic, modular and easy to use KM implementation methodology that...

This paper presents an attempt to study and monitor the evolution of research on prediction markets (PM). It provides an extended literature review and classification scheme. The former consists of 155 articles, published between 1990 and 2006. The results show that an increasing volume of PM research has been conducted in a very diverse range of a...

Despite the significant boost that some renewable energy sources have undergone lately, partly promoted by the favourable EU legislation, biomass seems to face difficulties in realising its expected share in energy production. Some major reasons for this are the complexity of a bioenergy system and its related fuel supply chain, the wide variety of...

The terms of growth and environment are historically proven not to be compatible in principles, methods and targets. Economic investments are usually accompanied by actions that could not easily be characterized as environmentally friendly, while the strict application of environmental directives often results in halting development. Moreover, the...

The importance of forecasting in transforming strategic objectives into decisions is apparent. Lately, traditional forecasting methods have been depicted as being inferior to Artificial Intelligence (AI) approaches (such as neural networks) which, by definition, are attempting to simulate the human decision making process and model the experts’ k...

This paper presents the re-engineering of the forecasting process of a medium-size Greek company operating in the wood industry. The analysis of the existing forecasting process was undertaken with the use of specific techniques, such as personal interviews, the construction of GRAI grids and the design of process charts. The problematic areas were...

This paper proposes design rules in order to simplify current MRP II software systems and make them suitable for the small manufacturing firm. Simplification rules apply to production data management by reducing database complexity. This has consequences to medium-term requirements planning which is moved toward the realization of simultaneous mate...

Purpose of this paper is to analyse and compare the behavior of workload control models in flow shops of both the MTO (Make-To-Order) and MTS (Make-To-Stock) classes. A simulation model has been built, where a manufacturing cell is loaded through an input control mechanism with shop orders coming from a pool. The pool itself is fed with planned ord...

In the complex environment of late modernity, organizations, large and small, are challenged by corporate crises more than ever. Thus, not surprisingly Crisis Management has gained additional attention during the last two decades. Yet, the knowledge aspects of crises' management theories and the role of effective knowledge retrieval and sharing in...

This study has the objective to apply new Information and Communication Technologies (ICT) and multi-agent modelling concepts in order to support the business process of production orders release in extended/virtual enterprises. In a previous publication (Tatsiopoulos, Computers in Industry, 33, 335–344, 199721. Tatsiopoulos , IP . 1997 . An orders...

During the last few years, a large number of new procurement business models has been developed, mostly concerning companies operating in the private sector. Their main objective is the introduction of new technologies such as e-business for the fulfilment of the procurement process of indirect goods. Lately, such models are also developed for orga...

This paper presents the development of a decision support system used by an oil downstream company for routing and scheduling purposes. The studied problem refers to a complex delivery process of oil products from a number of distribution centers to all customers. The latest rapid advance of operations research (OR) applications, in the form of adv...

This paper describes a model, which simulates the cotton biomass supply chain. The research has been carried out within the frame of a project that examined the feasibility of producing energy from the chopped cotton-plant stalks after they are cut and after the seed cotton is collected. The heating value of the dry stalks is high and can be used f...

The introduction of complicated and expensive Enterprise Resource Planning Systems (ERP) in companies operating in the process industry has become a strategic issue. The success of Information Technology (IT) implementation projects is dependent upon technological issues (software and hardware), the design of new efficient processes and the utilisa...

This paper presents a methodology and a case study for supply chain management in the clothing industry that makes extensive use of the virtual enterprise paradigm. The main research goal was to design and implement a prototype e-business software component and carry out tests in several industrial users. The research effort resulted in the extende...

Η παρούσα εργασία έχει σαν αντικείμενο την μελέτη της ροής εργασίας του συστήματος Κρατικών Προμηθειών με στόχο τον τελικό προσδιορισμό των προδιαγραφών του κατάλληλου λογισμικού ροής εργασίας που θα υποστηρίξει το νέο σύστημα ηλεκτρονικών κρατικών προμηθειών, στο πλαίσιο του έργου ανάπτυξη Εθνικού Συστήματος Ηλεκτρονικών Δημοσίων Προμηθειών (ΕΣΗΔΠ...