Time filter

Source Type

Kavala, Greece

The Eastern Macedonia & Thrace Institute of Technology is a public institute providing university-level education in Eastern Macedonia and Thrace. The institute has three campuses; the main campus in St. Lukas, Kavala, and additional campuses in Drama and Didymoteicho, Evros regional unit. The TEI of Kavala has 13,500 registered students, ranking seventh among the 16 technological educational institutes in Greece in terms of students. Wikipedia.

Akoumianakis D.,Technological Educational Institute of Kavala
Journal of Enterprise Information Management | Year: 2014

Purpose: The purpose of this paper is to investigate boundary spanning tactics in a cross-organizational virtual alliance and discuss the analytical value of "digging" into technology for excavating boundaries and understanding their dynamic and emergent features. Design/methodology/approach: Although boundaries, their role and implications have been extensively investigated across a variety of online settings, the results are inconclusive as to the features of technology that create, dissolve or re-locate boundaries. This is attributed to the fact that in most cases technology is addressed as a black box - a discrete artefact of practice - without seeking justification for the inscribed functions that enable or constrain use. The paper overcomes these shortcomings by analysing digital trace data compiled through a virtual ethnographic assessment of a cross-organizational tourism alliance. Data comprise electronic traces of online collaboration whose interpretive capacity is augmented using knowledge visualization techniques capable of revealing dynamic and emergent features of boundary spanning. Findings: Boundary spanning in virtual settings entails micro-negotiations around several types of boundaries. Some of them are either enforced by or inscribed into technology, while others are enacted in practice. Knowledge visualization of digital trace data allows "excavation" of these boundaries, assessment of their implications on distributed organizing of online ensembles and discovery of "hidden" knowledge that drives boundary spanning tactics of collaborators. Practical implications: In cross-organizational collaborative settings, boundary spanning represents an enacted capability stemming from the intertwining between material and social/collective agencies. Consequently, boundaries surface as first class design constructs, directing design attention not only to features inscribed in technology (i.e. user profiles, registration mechanisms, moderation policies) but also the way such features are appropriated to re-shape, re-locate or dissolve boundaries. Originality/value: An empirical data pool compiled through virtual ethnographic assessment of online collaboration is revisited and augmented with knowledge visualization techniques that enhance the interpretive capacity of the data and reveal "hidden" aspects of the collaborators' boundary spanning behaviour and tactics. © Emerald Group Publishing Limited. Source

Dermentzis K.,Technological Educational Institute of Kavala
Journal of Hazardous Materials | Year: 2010

Electrostatic shielding zones made of electrode graphite powder were used as a new type of ionic and electronic current sinks. Because of the local elimination of the applied electric field, voltage and current within the zones, ions are led inside them and accumulate there. The current sinks were implemented in electrostatic shielding electrodialysis of a simulated nickel plating rinse water containing 100 mg L -1 nickel and electrodeionization of a 0.001 M NiSO 4 solution with simultaneous electrochemical regeneration of the ion exchange resin beds. Pure water was obtained with a Ni 2+ ion concentration of less than 0.1 mg L -1 at a flow rate of 2.02 × 10 -4 dm 3 s -1 diluate stream and a current density of 30 A m -2. © 2009 Elsevier B.V. All rights reserved. Source

Konguetsof A.,Technological Educational Institute of Kavala
Journal of Mathematical Chemistry | Year: 2010

With this paper, a new algorithm is developed for the numerical solution of the one-dimensional Schrödinger equation. The new method uses the minimum order of the phase-lag and its derivatives. Error analysis and the numerical results illustrate the efficiency of the new algorithm. © 2009 Springer Science+Business Media, LLC. Source

Kyzas G.Z.,Technological Educational Institute of Kavala
Materials | Year: 2012

In this study, the decolorization of industrial textile wastewaters was studied in batch mode using spent "Greek coffee" grounds (COF) as low-cost adsorbents. In this attempt, there is a cost-saving potential given that there was no further modification of COF (just washed with distilled water to remove dirt and color, then dried in an oven). Furthermore, tests were realized both in synthetic and real textile wastewaters for comparative reasons. The optimum pH of adsorption was acidic (pH = 2) for synthetic effluents, while experiments in free pH (non-adjusted) were carried out for real effluents. Equilibrium data were fitted to the Langmuir, Freundlich and Langmuir-Freundlich (L-F) models. The calculated maximum adsorption capacities (Qmax) for total dye (reactive) removal at 25 °C was 241 mg/g (pH = 2) and 179 mg/g (pH = 10). Thermodynamic parameters were also calculated (ΔH0, ΔG0, ΔS0). Kinetic data were fitted to the pseudo-first, -second and -third order model. The optimum pH for desorption was determined, in line with desorption and reuse analysis. Experiments dealing the increase of mass of adsorbent showed a strong increase in total dye removal. © 2012 by the authors. Source

Kyzas G.Z.,Technological Educational Institute of Kavala
Materials | Year: 2012

This work aims to study the removal of Cu(II) and Cr(VI) from aqueous solutions with commercial coffee wastes. Materials with no further treatment such as coffee residues from café may act as adsorbents for the removal of Cu(II) and Cr(VI). Equilibrium data were successfully fitted to the Langmuir, Freundlich and Langmuir-Freundlich model (L-F). The maximum adsorption capacity of the coffee residues can reach 70 mg/g for the removal of Cu(II) and 45 mg/g for Cr(VI). The kinetic data were fitted to pseudo-first, -second and -third order equations. The equilibrium was achieved in 120 min. Also, the effect of pH on adsorption and desorption was studied, as well as the influence of agitation rate. Ten cycles of adsorption-desorption were carried out revealing the strong reuse potential of these low-cost adsorbents; the latter was confirmed from a brief economic approach. © 2012 by the authors. Source

Discover hidden collaborations