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During recent years, the theme of Knowledge Cities (KC) has evolved as a major topic of interest, in the context of the knowledge-based development (KBD) field. The KC theme, being multi-dimensiona...

The concept of the Knowledge City is a subfield of the Knowledge-Based Development which, during the last years, has attracted the interest of many researchers and practitioners. Various cities around the world have also undertaken considerable efforts and initiatives so as to be developed or to enhance their status as a Knowledge City. However, their approaches were rather ad-hoc and spontaneous and were not based on a pre-defined methodology. The research community has only recently begun to concentrate on the direction to substantiate the fundamental principles of Knowledge Cities and to define unified methodologies for their design, development and operation. Under this prism, the authors have recently proposed such a methodology, called KnowCis. The application of this methodology is currently in progress, on a Greek municipality. The municipality incorporates some special characteristics and features that render it a very advantageous case for this pilot application. This paper refers to the characteristics of the municipality and to the application of the KnowCis methodology, presents the progress of the effort and the preliminary results until now and provides useful insights on the forthcoming actions and plans of the city's administration. The outcomes, results and lessons-learnt of this pilot application will permit to fine-tune the KnowCis methodology.

Nowadays, it is commonly accepted in both researchers' and practitioners' communities that many disciplines and practices of the knowledge management (KM) field are also relevant and applicable to the knowledge-based development. This is reflected by the fact that the theme of knowledge cities (KCs) is now a ‘hot’ topic of interest and discussion. However, as it also happened with the early stages of evolution of KM, there is neither a coherent framework nor a unified methodology for the design and implementation of successful KCs. The real success of KCs is under investigation in the research community. In this direction, the authors propose a set of hypotheses for the design, development and operation of successful KCs. Then, based on an empirical evaluation of several case studies that have been successfully put in real practice they discuss the support of each case to these hypotheses. The key findings are expressed as a framework for building successful KCs.

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.

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

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.

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.