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PurposeTo control and reduce the time and the cost of implementation and to achieve optimal adaptation of the processes and structures of the enterprise in an ERP environment.Design/methodology/approachThis paper presents a fundamental methodology based on goal directed project management (GDPM) principles which supports the complicated process of implementation and optimal adaptation (IOA) of an ERP system.FindingsBy implementing this methodology it was found that it is able to control and reduce the time and the cost of implementation and to achieve optimal adaptation of the processes and structures of the enterprise in an ERP environment.Research limitations/implicationsBased on the above methodology a system must be developed, which will aim at providing the project manager with the ability to create all the necessary elements for the management and realization of the project and to lead the consultant during the IOA process of ERP systems.Practical implicationsThis methodology was connected to, and tested with the operations and capabilities of an ERP commercial package in one of the leading software houses in Greece. The functional result of this methodology was proved to support considerably the process of IOA of SEn in the companies‐customers.Originality/valueThis paper provides a generic research in this technological field concerning small or medium‐sized enterprises based on the GDPM principles which aims at the facilitation and effective guidance for the installation process IOA in all stages and in all levels of analysis.

The effects of rootstock variety (41B, 1103P and 110R), irrigation level (0.50, 0.75 and 1.00 of the evapotranspiration) and water quality (recycled versus freshwater) on water relations and gas exchange of potted Soultanina grapevines were investigated during two growing seasons. An early reduction of predawn leaf water potential ( Ψ pd ) was detected for vines irrigated with recycled water in both the seasons. However, assimilation rate ( A ) and stomatal conductance ( g s ) were reduced only late in the first year at higher irrigation levels. This was consistent with the higher reduction of Ψ pd at these treatments indicating that the development of a water deficit due to salt accumulation reduced gas exchange. At midday during 1998, leaves on vines grafted on 1103P and 110R had lower leaf water potentials and higher g s and A . An opposite effect was however observed early in June the following season, although later in that season no differences were detected among rootstocks. That differentiation of rootstock effect between seasons may have been induced by alterations in source/sink relations due to differences in yield among rootstocks and its effects on leaf area. Irrigation level strongly affected water relations and gas exchange. Both A and g s were significantly correlated with soil moisture. A differentiation in these relations was observed among rootstocks late in 1998 which probably resulted from the change in leaf area development among rootstocks during that period.

Over the past several years, there have been intensive discussions about the importance of knowledge management (KM) in our society. Nowadays, it is commonly accepted that many KM disciplines and practices are relevant to the social‐level knowledge‐based development. In this context, the new theme of “knowledge cities” came to the front. This paper attempts on the one hand to define the concept in a coherent way – presenting also its main implications and benefits – and on the other hand, to examine – on a worldwide scale – the different models of knowledge cities as well as modes of practice. The authors were based on a broad range of published works, including papers, books, reports and Web sites. The main approach was to briefly present the existing views of the concept, accompanied by some criteria determining a knowledge city. The authors also tried to provide a meaningful and concise review of existing cases, avoiding to get into many confusing details. This review provided valuable input for the definition of the key success factors and main benefits related to knowledge cities. This new concept is currently a main topic of interest for the research community and practitioners. It becomes clear that it has important benefits and in this way, focused research is needed towards many directions, in order for it to become a part of our life in near future. This integrated review is a very useful source of information for academics and practitioners who want to be acquainted with the knowledge cities concept.

Managing large amounts of information and efficiently using this information in improved decision making has become increasingly challenging as businesses collect terabytes of data. Intelligent solutions, based on neural networks (NNs) and genetic algorithms (GAs), to solve complicated practical problems in various sectors are becoming more and more widespread nowadays. The current study provides an overview for the operations researcher of the neural networks and genetic algorithms methodology, as well as their historical and current use in business. The main aim is to present and focus on the wide range of business areas of NN and GA applications, avoiding an in‐depth analysis of all the applications – with varying success – recorded in the literature. This review reveals that, although still regarded as a novel methodology, NN and GA are shown to have matured to the point of offering real practical benefits in many of their applications.

Some analysts have claimed that the volatility of an asset is caused solely by the random arrival of new information about the future returns from the asset. Others have claimed that volatility is mainly caused by trading. In any case it is a common belief that volatility is of great importance in finance and it is the factor that plays the most important role in determining option prices. This paper discusses the development of a decision support system (D‐TIFIS) for options trading based on volatility forecasting. In order to evaluate the system, data were used from the Greek FTSE/ASE 20 stock index as well as at the money call and put prices on the specific index.

Knowledge management (KM) has recently received considerable attention in the computer information systems community and is continuously gaining interest by industry, enterprises and government. Decision support and KM processes are interdependent activities in many organizations. In all cases, decision makers always combine different types of data and knowledge available in various forms in the organization. One of the key – but also criticized – building blocks for advancing this field of knowledge management and consequently supporting the decision making is artificial intelligence (AI). In this framework, this paper aims to improve understanding of AI towards knowledge management. It examines and discusses both the potential and the limitations of basic AI technologies in terms of their capability to support the KM process and shares thoughts and estimations on further research on the development of the next generation decision support environments.

Knowledge Management (KM) has recently received considerable attention in the computer information systems community and is continuously gaining interest by industry, enterprises and academia. As we are moving into an era of "knowledge capitalism", knowledge management in combination with information management will play a fundamental role towards the success of transforming individual knowledge into organizational knowledge. Higher education (HE) institutions are in the knowledge business, since they are involved in knowledge creation, dissemination and learning. The increasing economic importance of knowledge, which nowadays redefines the links among education, work and learning, makes the role of KM in HE crucial. In this framework, this paper presents the key concepts of human-computer interaction in knowledge management, discusses their applicability to HE and proposes the creation of learning organisations in HE institutions, as an innovative way to apply KM to HE.

A great challenge for today’s companies is not only how to adapt to the changing business environment but also how to gain a competitive advantage from the way in which they choose to do so. As a basis for achieving such advantages, companies have started to seek to improve the performance of various operations. Forecasting is one of them; it is important to firms because it can help ensure that effective use of resources is made. In the market there are a number of off‐the‐shelf system products, which provide forecasts. The new trend, of moving traditional software packages to Web services, has pushed forecasting to a new dimension, named by the authors as “e‐forecasting”. In this paper, a first approach to e‐forecasting is made by throwing light on several aspects and a survey is presented which aims at identifying existing Web forecasting services.

Intelligent solutions, based on artificial intelligence (AI) technologies, to solve complicated practical problems in various sectors are becoming more and more widespread nowadays. AI-based systems are being developed and deployed worldwide in myriad applications, mainly because of their symbolic reasoning, flexibility and explanation capabilities. This paper provides an overview for the researcher of AI technologies, as well as their current use in the field of short term electric load forecasting (STELF). The history of AI in STELF is outlined, leading to a discussion of the various approaches as well as the current research directions. The paper concludes by sharing thoughts and estimations on AI future prospects in this area. This review reveals that although still regarded as a novel methodology, AI technologies are shown to have matured to the point of offering real practical benefits in many of their applications.

Companies deal with many decision‐making processes whose impact on the global performance can be very strong. As a consequence, the role of the decision support systems (DSSs) within the organization is critical. Considering the imprecise or fuzzy nature of the data in real‐world problems, it becomes obvious that the ability to manage uncertainty turns out to be a crucial issue for a DSS. In this framework, this paper discusses the key role of fuzzy logic (FL) in the DSSs, presents new applications of FL in DSSs in various sectors and identifies new challenges and new directions for further research.

During the last decade, many companies have made large investments in the development and implementation of enterprise resource planning (ERP) systems. However, only few of these systems developed or installed have actually considered maintenance strategies. Maintenance is a complex process that is triggered by planned periodic repair (scheduled or planned maintenance), equipment breakdown or deterioration indicated by a monitored parameter (unplanned or emergency maintenance). This process requires planning, scheduling, monitoring, quality assurance and deployment of necessary resources (workshop, manpower, machines, equipment, tools, spare parts, materials). Proper design and integration of maintenance management into ERP systems enable enterprises to effectively manage their production planning and scheduling, as well as to analyze their maintenance history so as to carry out cost analysis and produce future projections of failure trends. The present work presents the design of an object‐oriented maintenance management model and its integration into an ERP system. The proposed model was designed towards the development of innovative industrial software regarding the optimum management of maintenance in a wide range of business areas.

In recent times, Artificial Neural Networks (ANNs) have been receiving increased attention as tools for business applications. In this paper, we focus on the use of ANNs in the field of production scheduling. The history of ANNs in production scheduling is outlined, leading to a discussion of the various approaches, as well as the current research directions. The paper concludes by sharing thoughts and estimations on the future prospects of ANNs in this area.

Knowledge management has recently received considerable attention in the computer information systems community and is continuously gaining interest from industry, enterprises and government. As we move towards building knowledge organizations, knowledge management in combination with information management will play a fundamental role towards the success of transforming individual knowledge into organizational knowledge. In this framework, this paper discusses the key concepts of human‐computer interaction in knowledge management, identifies new challenges of knowledge management for Web‐based business and proposes a “user agent architecture” for knowledge management in e‐learning environments. User agents use artificial neural network technology and can be used in various e‐learning or e‐training environments, in order to provide them with means of managing information stored, filtering content and enabling better knowledge adoption on behalf of their users.

Planning and scheduling are forms of decision making, which play a crucial role in manufacturing as well as in service industries. In the current competitive environment, effective sequencing and scheduling has become a necessity for survival in the marketplace. A great challenge for today’s companies is not only how to adapt to this changing, competitive business environment but also how to draw a competitive advantage from the way in which they choose to do so. Intelligent solutions, based on expert systems, to solve problems in the field of production planning and scheduling are becoming more and more widespread nowadays. Proposes an expert system, which uses the prevailing conditions in the industrial environment in order to select and “fire” dynamically the most appropriate scheduling algorithm from a library of many candidate algorithms.

Intelligent solutions, based on expert systems, to solve problems in the field of production planning and scheduling are becoming more and more widespread nowadays. Especially the last decade has witnessed a growing number of manufacturing companies, including glass, oil, aerospace, computers, electronics, metal and chemical industries—to name just a few—interested in the applications of expert systems (ESs) in manufacturing. This paper is a state-of-the-art review of the use of ESs in the field of production planning and scheduling. The paper presents famous expert systems known in the literature and current applications, analyzes the relative benefits and concludes by sharing thoughts and estimations on ESs future prospects in this area.

Extrusion blown polyethylene and polyethylene/montmorillonite nanocomposite films were cold stretched to various ratios to quantify the influence of the crystal orientation and the nanofiller alignment on their dielectric breakdown performance. It was found that the crystal orientation could increase the breakdown strength (EBD) in the stretched blown films. The aligned pseudo-2D inorganic nanoclays provided additional strong improvements in EBD that can be superimposed to any EBD enhancement due to the polymer crystal orientation. At high filler loadings and high stretching ratios, the onset of percolation was observed through a substantial improvement in the dielectric breakdown strength.

Pyrolysis appears to be a promising recycling process since it could convert the disposed polymers to hydrocarbon based fuels or various useful chemicals. In the current study, two model polymers found in WEEEs, namely polycarbonate (PC) and high impact polystyrene (HIPS) and their counterparts found in waste commercial Compact Discs (CDs) were pyrolysed in a bench scale reactor. Both, thermal pyrolysis and pyrolysis in the presence of two catalytic materials (basic MgO and acidic ZSM-5 zeolite) was performed for all four types of polymers. Results have shown significant recovery of the monomers and valuable chemicals (phenols in the case of PC and aromatic hydrocarbons in the case of HIPS), while catalysts seem to decrease the selectivity towards the monomers and enhance the selectivity towards other desirable compounds.

Novel poly(butylene succinate) (PBSu) nanocomposites containing 5 and 20 wt% mesoporous strontium hydroxyapatite nanorods (SrHNRs) and silica nanotubes (SiNTs) were prepared by melt-mixing. A systematic investigation of the thermal stability and decomposition kinetics of PBSu was performed using pyrolysis-gas chromatography–mass spectroscopy (Py-GC–MS) and thermogravimetry (TG). Thorough studies of evolving decomposition compounds along with the isoconversional and model-fitting analysis of mass loss data led to the proposal of a decomposition mechanism for PBSu. Moreover, the effects of SrHNRs and SiNTs on the thermal stability and decomposition kinetics of PBSu were also examined in detail. The complementary use of these techniques revealed that the incorporation of SiNTs in PBSu does not induce significant effects neither on its thermal stability nor on its decomposition mechanism. In contrast, the addition of SrHNRs resulted in the catalysis of the initial decomposition steps of PBSu and also in modified decomposition mechanisms and activation energies. The evolving gaseous products of PBSu and their evolution pattern in the SiNT nanocomposites were the same as in neat PBSu, while they were slightly modified for the SrHNR nanocomposites, confirming the findings from thermogravimetric analysis.

Effective modelling is one of the most important and difficult steps in the development of reliable information systems, and production planning and control in industry is very difficult. This paper presents an object-oriented analysis (OOA) and describes the design of a model for production planning and control in a customised industrial environment. The proposed model was designed for the development of innovative industrial software for the optimum management of production planning in a wide range of business areas.

It is common knowledge that during the last decade markets have become extremely competitive with product variety increasing continuously and product life cycles shortening. Many manufacturing companies, which hitherto satisfied their customers while operating specific production systems, were recently obliged to reconsider because of the potential superiority of other “manufacturing philosophies”. In the literature, we meet a great variety of production systems and manufacturing philosophies, while, on the other side, in industry we usually find different combinations of “primary” productions systems. In this paper, we present the existing “state‐of‐the‐art” theoretical and experiential knowledge about productions systems, as well as describe their basic characteristics in a useful, exact and comprehensive way for practitioners and software houses who want to have a knowledge base for further research and practical implementation in the wider field of production management, planning and scheduling.

This paper presents an overview of regional water resources in Greece including water availability, water uses, wastewater reclamation, and reuse trends. Water demand has increased tremendously in recent decades. Despite adequate precipitation, several regions are under water stress due to temporal and regional variations of precipitation, the high rate of evapotranspiration and the high cost of transporting water over the mountainous terrain. To address the problem of water stress, integration of reclaimed wastewater into water resources management is proposed. Data about the current situation of municipal wastewater treatment and reuse options are presented, and regional and temporal trends for wastewater reclamation and reuse are summarized. It is revealed that by proper management and reuse of the effluent from existing municipal wastewater treatment plants, water availability can be increased by 3.2 percent

In this paper we consider the use of ontologies as the basis for structuring and simplifying the process of constructing real‐time problem‐solving tools, focusing specifically on the task of production scheduling. In spite of the commonality in production scheduling system requirements and design, different scheduling environments invariably present different challenges (e.g. different constraints, different objectives, different domain structure, etc.). The proposed methodology for building ontologies used for production scheduling systems represents a synthesis of extensive work in developing constraint‐based scheduling models for a wide range of applications in manufacturing and production planning. Since the effective modeling is one of the most important and difficult steps in the development of reliable information systems, and taking into consideration the fact that the general problem of the production scheduling in the industries is very difficult and still unsolved, one can easily estimate the merit of this methodology.

The knowledge of the intrinsic pore structure of coals is significant in elucidating the kinetics of mass transport and chemical reaction that leads to design of more efficient coal combustion and conversion equipment. The results of pore structure studies of Greek lignite are reported in this work. Isothermal drying of Greek lignite samples, under vacuum, caused mesopore structure evolution despite the severe (∼50%) particle size contraction due to heating. Mesopore volume and surface area were increased as the drying temperature was raised to 200°C while further drying up to 250°C caused a mesopore volume and surface area decrease. Lignite drying at 100°C for up to 3 h resulted in a monotonic increase of the mesopore structure properties while heating for a longer period i.e., 6 h, despite a slight increase of weight loss, caused pore volume and surface area reduction. Nitrogen sorption (77 K) hysteresis data obtained for partially dried samples have been processed to deduce BET surface area and pore si...

An investigation of the thermal drying of lignite has been carried out, by using an indirect heat pilot rotary drum. The process aims at the production of dry lignite and clean steam as part of a gasification procedure. Both flighted and bare drum modes have been employed. Temperature profiles along the dryer length, the amount of evaporation (moisture conversion) and the solids residence time distribution (RTD) were measured. A non-isothermal model was tested under three different regimes of solids flow. Model integration, by taking account of experimental amount of evaporation at dryer exit and temperature profiles along the dryer length, has been utilized in the validation of drying kinetics and heat transfer correlations. Model predictions compare satisfactorily with the operating data of an indirect heat industrial lignite dryer. Overall heat transfer coefficients of the pilot rotary dryer were found to agree well with those reported for direct heat dryers.

From the very earliest moments in the modern history of the computer, scientists have dreamed of creating advanced systems which would simulate human meditation and reasoning. Of all the modern technological quests, this research to create artificially intelligent computer systems has been one of the most ambitious and fascinating. Although attempts had been made more than 30 years ago to develop and apply such systems to the medical sciences, the field languished for decades. In this framework, this paper aims to share thoughts and estimations on the important role of expert systems in medicine and address their future as well as the trends that are foreseen in this area.

Within the last decade many projects have been implemented in order to provide technical assistance (TA) to countries which have initiated their transition from centrally planned to market economies (mainly countries of Eastern Europe being previously under the Soviet regime). The “monitoring and evaluation” function (M&E) helps in seeing whether each TA project is being developed as per its design and achieves its objectives by providing management information on the project’s implementation. In this framework, the necessity for the creation of an overall M&E database system emerged, with the main objective to improve not only the management of TA projects but also the design and planning of future TA projects.

This paper seeks to investigate the relative subsistence potential of Late Minoan I households in Crete on the basis of the archaeological evidence. It aspires to develop a methodological framework for the examination of the subsistence economy based on storage containers (pithoi) and installations recovered in seventy houses. By identifying different storage strategies and converting capacity estimates into calorific values we infer differences in households’ subsistence potential. Ordinary households had low subsistence potential and only a few of the elite households had a markedly higher subsistence potential. While this ensured for these elite households high self‐sufficiency and participation in conspicuous consumption, it could not have served in alleviating the community's food shortages, should these have occurred. The emerging Late Minoan IB picture attests to the highly centralized and hierarchical organization of the subsistence economy, in keeping with the centralizing trend manifest...

In Part II of this work a flighted pilot rotating cylindrical drum, intended to be used as either a dryer or calciner ( kiln) has been used to investigate the flow, through it, of pulverized moist lignite. Tracer pulse input - response experiments have been performed. Residence Time Distribution ( RT) data have been deduced for three types of flight geometry, namely: Rectangular ( RA) Equal Angular Distribution ( E.A.D.) and Equal Horizontal Distribution ( E.H.D) For each flight shape, mean residence time t¯ has been correlated with drum operating conditions. The sequence ⩾ t¯ EAD t¯ EAD has been validated. A comparison between the residence time predictions for the flighted and the bare drum has indicated that t for the former may be higher by up to 3.5 times than that for the latter. Exceptionally high solids hold-up values ( Z= 0.13− 0.42) have been observed and compared to theoretical predictions. Particle size segregation during lignite flow through the flighted drum was not confirmed.

Within the last decade many projects have been implemented in order to provide technical assistance (TA) to countries, which have initiated their transition from centrally planned to market economies (mainly countries of Central and Eastern Europe being previously under the Soviet regime). The monitoring and evaluation exercise aims at assisting these TA projects in achieving their objectives, by providing management information on the projects’ implementation, so that structured management decisions can be taken, if and when needed. In this framework, the necessity for creation of an overall M&E database system emerged. The IMES was developed for the needs of the European commission (DGLA) and its main objective was to improve the Management Reporting on Tacis progress and results, by extracting relevant information on projects’ performance from the monitoring and evaluation reports and by producing overall statistics at NIS (New Independent States) level.

The enzymatic hydrolysis of cellulose toward fermentable glucose is of paramount importance for the production of ethanol or other high-value chemicals from lignocellulosic biomass via the biochemical route. A pretreatment step is usually required that alters the structure and composition of biomass, reduces its recalcitrance, and allows the efficient enzymatic conversion of carbohydrates into sugars. Biomass pretreatment aims mainly at the selective separation of hemicellulose and/or lignin, either as oligomers or as smaller sugar and phenolic molecules, which can be further converted enzymatically or via chemical catalysis to platform chemicals or fuel precursors. In this chapter, a review of the most widely applied pretreatment methods is presented, with the aim of elucidating the role of chemical or biochemical catalysis in this first step of biomass valorization.

In recent years, high volatility in oil prices and global climate change led to an increased interest in biofuel production to reduce dependency on foreign fossil fuel. Domestically produced plant feedstocks are environmentally friendly renewable substitutes for fossil-derived fuel and are expected to stabilize fuel prices. Plant-derived energy can offer rural development and other environmental, social and energy security benefits for local societies. Crops, grasses, trees, forest-residues and aquatic plants, all can be used as potential biofuel feedstocks. To meet the increased global and regional demand for bioenergy, evaluation and improvement of current and emergent plant feedstocks is urgently needed to reduce the cost of the resulting biofuels.

The remarkable physical properties of carbon nanotubes and their versatile chemical reactivity leading to various types of surface organo-functionalization were the main reasons why CNTs have become one of the most important types of nano-additives for the development of novel polymer (including epoxy) nanocomposites with improved and sometimes unique properties. The present chapter deals with the organo-functionalization of carbon nanotubes and the preparation of the respective epoxy – CNT nanocomposites. The effect of functionalization on dispersion of CNTs and on the final properties of the nanocomposites is discussed, while emphasis is given on the reactivity of the functional groups and their participation in the curing process of epoxy resins.

Back-scattered Scanning Electron Microscopy (BSEM) has been used to identify weathering mechanisms occurring in two oolitic limestones from urban areas in London and Cambridge, United Kingdom. From a petrographical point of view, the two stones can be described as oosparite and oomicrite, their main distinctive feature being the crystal size of the cement binding the limestone grains together. The sulphation mechanism, i.e. the replacement of calcium carbonate (calcite: CaCO3) by calcium sulphate dehydrate (gypsum: CaSO4 2H2O), at the surface and within the stone fabric is confirmed as the general decay process. Differences in macroporosity/permeability distribution in the two limestones lead to different weathering patterns. BSEM provides evidence that gypsum patinas still commonly found on limestone facades in polluted urban locations are advancing inside the diseased stone and that their removal is urgently needed to arrest the growth of the in-growing weathering front.

The yield stresses of coal-water mixtures as functions of solids volume fraction, suspended particle size, and suspension pH were measured using the vane method. The suspension yield stress-solids volume fraction data were used to estimate the asymptotic values of solids concentration in the limit of infinite yield stress. The limiting solids volume fractions, obtained by such an extrapolation, were found to be approximately the same as those estimated independently from the irreducible sediment volumes obtained by centrifugation. The yield stress-concentration dependence was found to depend on particle size as well as pH, or the corresponding zeta potential which was also measured. However, for a given particle size mix the yield stress-concentration plots for different pH appeared to converge, as the yield stress became large, and to approach a common asymptotic value of solids concentration in the limit of infinite yield stress. A number of different extrapolation procedures were tested to establish the type of plot capable of providing a consistent, unambiguous value of these limiting concentrations. The procedures for estimating the maximum packing solids concentrations from centrifugal sedimentation were also tested by varying the speed and the duration of centrifugation. The solids concentration dependence of the yield stress of CWM was found to be described by two-parameter non-linear relationships based upon the mean interparticle spacing, and incorporating the maximum packing volume of solids. Furthermore, it is established that the yield stress is proportional to the reciprocal of the mean particle size.

Congenital lymphangiectasia with lymphedema is a disorder constituting the main defect in many different genetic syndromes. Herein we describe a 23-year-old male patient with congenital lymphangiectasia and severe lymphedema of the right leg, scrotum, and abdominal wall, who presented with end-stage renal disease, presumably due to cystic renal lymphangiectasia, and is undergoing chronic hemodialysis treatment.

Nowadays, knowledge is considered as one of the most valuable assets of an enterprise which has to be managed efficiently and effectively in order to gain a competitive advantage in the knowledge economy era. Knowledge Management (KM) evolved into a strategic management approach, finding application not only in the business world but also in other areas such as education, government and healthcare. In this way, the new link between KM and KBD created the appropriate environment for the advent of a new concept in the scientific and practitioners’ communities, the concept of “Knowledge City” (KC). Nowadays, the theme of KCs is a ‘hot’ topic of interest and discussion. The process for developing a KC, is neither quick nor simple. This seems to be already understood by the research community, which the last few hears has begun to concentrate its efforts so as to develop appropriate frameworks, methodologies, tools, systems, etc so as to support the development of KCs. In this context, and given that there are still many pending issues, this article attempts to propose a taxonomy of KC research, by co instantaneously presenting the status with these major themes of KC research. The discussion presented on this article should be of value to researchers and practitioners.