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The paper presents a method for the decentralised solution of the optimal-power-flow (OPF) problem of large, interconnected power systems. The method decomposes the central OPF problem of a multiarea system into independent OPF subproblems, one for each area. The mathematical decomposition method is based on the decoupling of the first-order (KKT) conditions of the original system-wide OPF problem. The solutions of the OPF subproblems of the different areas are co-ordinated through a pricing mechanism until they converge to the system-wide OPF solution. The method requires no parameter tuning for reaching convergence or faster convergence. Results from the application of the method to several IEEE test systems are presented.

Abstract A forecast of transport activity, energy consumption and carbon dioxide emissions from transportation, carried out under ‘business as usual’ economic assumptions, is presented for the 10 countries of Central and Eastern Europe that have acquired the status of ‘accession countries’ to the European Union. Energy demand is projected under considerations of the dynamic evolution of transport modes and their use, the evolution of automotive fuel prices, which are assumed to gradually converge with Western European price levels within the current decade, and assumptions on efficiency improvements in all transport modes according to current technological trends and European regulations. The results, showing transportation energy demand to double and CO2 emissions to be 70% higher in 2030 compared to 2000, are compared with other published forecasts and discussed with a view to potential future energy and environmental impacts in these countries, outlining major policy implications.

Microbial production of ethanol might be a potential route to replace oil and chemical feedstocks. Bioethanol is by far the most common biofuel in use worldwide. Lignocellulosic biomass is the most promising renewable resource for fuel bioethanol production. Bioconversion of lignocellulosics to ethanol consists of four major unit operations: pretreatment, hydrolysis, fermentation, and product separation/distillation. Conventional bioethanol processes for lignocellulosics apply commercial fungal cellulase enzymes for biomass hydrolysis, followed by yeast fermentation of resulting glucose to ethanol. The fungus Neurospora crassa has been used extensively for genetic, biochemical, and molecular studies as a model organism. However, the strain's potential in biotechnological applications has not been widely investigated and discussed. The fungus N. crassa has the ability to synthesize and secrete all three enzyme types involved in cellulose hydrolysis as well as various enzymes for hemicellulose degradation. In addition, N. crassa has been reported to convert to ethanol hexose and pentose sugars, cellulose polymers, and agro-industrial residues. The combination of these characteristics makes N. crassa a promising alternative candidate for biotechnological production of ethanol from renewable resources. This review consists of an overview of the ethanol process from lignocellulosic biomass, followed by cellulases and hemicellulases production, ethanol fermentations of sugars and lignocellulosics, and industrial application potential of N. crassa.

Η ραγδαία άνοδος του ηλεκτρονικού εμπορίου φέρνει παράλληλη αύξηση των αρνητικών περιβαλλοντικών του επιπτώσεων. Για κάθε συσκευασία που αποστέλλεται, υπάρχουν ορατές περιβαλλοντικές επιπτώσεις (όπως ένα κουτί από χαρτόνι για ανακύκλωση ή μια πλαστική συσκευασία για απόρριψη) και ένα αόρατο αποτύπωμα (όπως το διοξείδιο του άνθρακα που εκπέμπεται κατά τη μεταφορά και την παράδοση). Αυτή η διπλωματική εργασία, εξετάζει την εξέλιξη του ηλεκτρονικού εμπορίου παράλληλα με την ραγδαία αύξηση του διαδικτύου καθώς και τις διαστάσεις της βιωσιμότητας του και τις αρνητικές περιβαλλοντικές επιπτώσεις που προκύπτουν. Ο πρωταρχικός στόχος της διπλωματικής είναι να αναδείξει το μείζων ζήτημα των συσκευασιών του ηλεκτρονικού εμπορίου. Πραγματοποιήθηκε συστηματική αναζήτηση για τον εντοπισμό επιστημονικών άρθρων και εργασιών που ασχολούνται με τη βιωσιμότητα του ηλεκτρονικού εμπορίου καθώς και για τη βιωσιμότητα στις συσκευασίες του ηλεκτρονικού εμπορίου, προκειμένου να κατανοηθούν καλύτερα οι αλλαγές στα υλικά και οι μορφές και να εντοπιστούν τα προβλήματα όπως η υπερσυσκευασία και η χρήση μη φιλικών προς το περιβάλλον υλικών. Ορισμένα προϊόντα συσκευασίας συνεχίζουν να κατασκευάζονται από μη ανανεώσιμα υλικά και έτσι περιορίζουν την ανάπτυξη του ηλεκτρονικού εμπορίου. Απαιτείται περαιτέρω έρευνα με σκοπό την παραγωγή νέων συσκευασιών από φιλικά προς το περιβάλλον υλικά, καθώς και παραγωγή συσκευασιών οι οποίες να είναι παράλληλα και ανθεκτικές, με σκοπό την αντοχή στον χρόνο ώστε να γίνετε επαναχρησιμοποίηση. Παράλληλα χρειάζεται και η ενημέρωση τον καταναλωτών σχετικά με την βιώσιμη συσκευασία, γ’ αυτόν τον σκοπό στην παρούσα διπλωματική εργασία, δημιουργήθηκε ερευνητικό ερωτηματολόγιο με στόχο την μελέτη αντίληψης των καταναλωτών σχετικά με την βιώσιμη συσκευασία και τον τρόπο διαχείρισης αυτών. Η βελτίωση των διαδικασιών διανομής με νέα, πιο αποτελεσματικά εργαλεία θα μπορούσε επιπλέον να συμβάλει στην άμβλυνση των περιβαλλοντικών επιπτώσεων των συσκευασιών.

After a halt of four years, the n TOF spallation neutron facility at CERN has resumed operation in November 2008 with a new spallation target characterized by an improved safety and engineering design, resulting in a more robust overall performance and e cient cooling. The rst measurement during the 2009 run has aimed at the full characterization of the neutron beam. Several detectors, such as calibrated ssion chambers, the n TOF Silicon Monitor, a Mi- croMegas detector with 10B and 235U samples, as well as liquid and solid scintillators have been used in order to characterize the properties of the neutron uence. The spatial pro le of the beam has been studied with a specially designed \X-Y

Purpose This paper aims to investigate the current energy status in the West Balkan countries and the related perspectives for renewable energy sources (RES) cooperation mechanisms, within the framework of RES Directive 2009/28/European Commission (EC), through the elaboration of a SWOT (strengths, weaknesses, opportunities, threats) analysis. Particular emphasis is laid on the case of Bosnia-Herzegovina, Croatia and Serbia. The SWOT analysis provides a clearer view of expanding RES in the West Balkans, as well as the level of utilization and potential of cooperation mechanisms and renewable energy in each country. Design/methodology/approach The adopted approach is mainly based on the context of a project co-financed by the Intelligent Energy Europe Programme, titled “Bringing Europe and Third countries closer together through renewable Energies (BETTER)” (project number: IEE/11/845/SI2.616378). The adopted approach incorporates the steps of desktop analysis, stakeholders’ mapping and engagement, key factors’ identification and analysis of results. Findings The barriers to expand RES in the region are significant. Currently, the region is electricity importer and by far not in the position to efficiently exploit the large RES potentials. It remains to be seen whether and to what extent cooperation mechanisms may be used in the Western Balkans and the EU by 2020. The unification of the fragmented electricity system and market-oriented reforms aim to join regional power markets and then to integrate with the European Union power market. There is a multitude of market barriers for RES, resulting in a high risk perception n by investors. Cooperation mechanisms could strengthen the regions’ policy frameworks and be a starting point to integrate the region’s energy systems and to overcome the fragmentation of the past two decades. Originality/value The potential of West Balkan countries to make use of the cooperation mechanisms provides opportunities for RES exporting between West Balkan and other European countries. An analysis of these opportunities for cooperation will allow drawing clearer conclusions on cooperation potentials and business cases for the region.

The Greek policy targeting residential energy efficiency has launched the “Residential Energy Saving” financial incentives program to assist in achieving the goals related to reducing energy use and GHG emissions. Considering the research gaps of previous work, the present study examines the sociodemographic, dwelling, and geographical characteristics, and the environmental awareness and behavior that affect individuals’ (a) actual decision to perform an energy-saving renovation of their dwelling; this has been previously examined, but not in the Greek context, (b) awareness of the incentives program; this has not been addressed in previous research, and (c) utilization of the program; this has not been addressed in previous research. Accordingly, we performed a questionnaire-based survey in Greece in 2019 (n = 451). Based on the development of three binary logistic regression models, it is indicated that the decision to perform an energy-saving renovation is affected by ownership status, year of construction, income, and environmental behavior; awareness is affected by education level, environmental awareness, and residence location; use of the incentives program is affected by residence ownership and year of construction, presence of senior citizens and education level. The study’s results, indicating the determinants of energy-saving renovation decisions and awareness and utilization of financial incentives programs, can assist policymakers in planning financial incentives adapted to different characteristics, thus achieving improved awareness and utilization of such tools.