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51.
52.
Georgios Fotopoulos 《The Annals of Regional Science》2012,48(3):719-741
Nonlinearities have been identified in recent literature on growth and convergence at the cross-country level and they have been associated with a number of variables of interest such as initial conditions and human capital accumulation. This research takes the analysis at the regional level within a European context while focusing on entrepreneurship and, using semiparametric regression techniques, provides evidence for nonlinear effects of the base-year income per capita on growth suggesting that convergence may be a phenomenon restricted to particular income bands. Entrepreneurship has a positive effect on regional growth and no serious departures from linearity are detected, while evidence for an almost L-shaped relationship between income per capita levels and self-employment rates was produced. A quality-adjusted proxy for human capital stock was found to be a positive and significant determinant of economic growth across European regions but, again, no departures for linearity were detected for this effect. 相似文献
53.
Georgios Papadopoulos Hanna Kurniawati Ahmed Shafeeq Bin Mohd Shariff Liang Jie Wong Nicholas M. Patrikalakis 《野外机器人技术杂志》2014,31(2):225-244
Over the past 10 years, significant scientific effort has been dedicated to the problem of three‐dimensional (3‐D) surface reconstruction for structural systems. However, the critical area of marine structures remains insufficiently studied. The research presented here focuses on the problem of 3‐D surface reconstruction in the marine environment. This paper summarizes our hardware, software, and experimental contributions on surface reconstruction over the past few years (2008–2011). We propose the use of off‐the‐shelf sensors and a robotic platform to scan marine structures both above and below the waterline, and we develop a method and software system that uses the Ball Pivoting Algorithm (BPA) and the Poisson reconstruction algorithm to reconstruct 3‐D surface models of marine structures from the scanned data. We have tested our hardware and software systems extensively in Singapore waters, including operating in rough waters, where water currents are around 1–2 m/s. We present results on construction of various 3‐D models of marine structures, including slowly moving structures such as floating platforms, moving boats, and stationary jetties. Furthermore, the proposed surface reconstruction algorithm makes no use of any navigation sensor such as GPS, a Doppler velocity log, or an inertial navigation system. 相似文献
54.
Marinos Vassilis Stoumpos Georgios Papouli Dimitra Papazachos Costas 《Bulletin of Engineering Geology and the Environment》2019,78(3):1795-1813
Bulletin of Engineering Geology and the Environment - This present paper presents an adopted methodology for Micro Tunnel Boring Machine (TBM) selection, based on the results of a... 相似文献
55.
Aikaterini P. Tzamourani Elisa Di Napoli Spiros Paramithiotis Georgios Economou-Petrovits Stavros Panagiotidis Efstathios Z. Panagou 《International Journal of Food Science & Technology》2021,56(8):3845-3857
The microbiological and physicochemical changes of industrially fermented Halkidiki and Conservolea green table olives were determined. Samples were analysed to monitor the population of lactic acid bacteria (LAB), yeasts and Enterobacteriaceae, together with changes in pH, acidity, salinity, colour, lactic acid, acetic acid and ethanol. LAB and yeast species diversity was evaluated at the beginning (1 day), middle (75 days) and final (135 days) stages of fermentation by RAPD-PCR genomic fingerprinting. Results revealed vigorous lactic acid processes as indicated by the dominance of LAB over yeasts. No Enterobacteriaceae could be detected after 30 days. Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) dominated in the beginning of fermentation in both varieties. In the end, Lactiplantibacillus pentosus (formerly Lactobacillus pentosus) and Pediococcus ethanolidurans prevailed in Halkidiki and Conservolea varieties, respectively. As for yeasts, Kluyveromyces lactis/marxianus and Pichia manshurica prevailed at the onset of fermentation in Halkidiki and Conservolea varieties, whereas in the end Pichia membranifaciens dominated in both varieties. 相似文献
56.
Multimedia Tools and Applications - In this paper, we propose a hybrid fog and cloud-aware heuristic for the dynamic scheduling of multiple real-time Internet of Things (IoT) workflows in a... 相似文献
57.
Papadopoulos Georgios Z. Mavromatis Alex Gallais Antoine Theoleyre Fabrice 《Wireless Networks》2021,27(1):367-381
Wireless Networks - Internet of things consist in the deployment of constrained and battery-powered devices with a radio interface. Most industrial applications require to respect strict... 相似文献
58.
Sotirios Karellas Dionysios Giannakopoulos Christina-Stavrula Hatzilau Ioannis Dolianitis Georgios Skarpetis Theodoros Zitounis 《Energy Efficiency》2018,11(5):1161-1175
The European Emissions Trading Scheme (EU ETS) covers approximately 45% of European greenhouse gases (GHGs), 11,000 stationary installations as well as aircraft operators. The EU ETS particularly affects the energy-intensive industries while it imposes a significant risk of “carbon leakage,” i.e., the risk of EU industry departing to countries with weaker restraints on GHG emissions. The EU glass industry, being capital intensive and also requiring long investment cycles, is the world’s largest glass producer with a market share close to one third of global production. Therefore, it is of significant importance to view the position of the EU ETS glass industry in terms of energy conservation possibilities. The present paper utilizes a vertical approach to provide information on both ETS market evolution and specific technical information to support technological innovation to the glass industry. EU ETS glass industry is analyzed regarding the balance between allocated European Union emission allowances (EUAs), verified CO2 emissions, and potential shortfall in allowances so as to determine the situation of glass industries and the extent of urge for energy-saving activities towards the strengthening of their position within the requirements of the EU ETS phase III. The replication potential of waste heat recovery (WHR) through batch preheating is specifically addressed since it is considered a promising technology according to the latest Best Available Techniques (BAT) reference document for the glass industry under Directive IED 2010/75/EU. A case study for a container glass furnace based on simulation results is presented investigating the impact of different operating and design configurations on specific energy consumption and CO2 emissions. 相似文献
59.
60.
Piotr Piela Jens Mitzel Erich Gülzow Jürgen Hunger Alexander Kabza Ludwig Jörissen Francesco Valle Alberto Pilenga Thomas Malkow Georgios Tsotridis 《International Journal of Hydrogen Energy》2017,42(31):20187-20200
The direct-search simplex method for function optimization has been adapted to performance optimization of polymer electrolyte membrane fuel cells (PEMFCs). The established method is strongly application oriented and uses only experimentally determined data for optimization. It is not restricted to discrete parameters optimums and does not require the use of third-party software or computational resources. Hence, it is easy to implement in fuel cell testing stations. The optimization consists of finding, for a given fuel cell load, an optimum set of values of the 7 fuel cell operating parameters: the fuel cell temperature, the reactants' stoichiometric ratios, the reactants' inlet relative humidity, and the reactants' outlet pressures, resulting in the highest fuel cell performance. The performance is measured using a scalar function of the operating parameters and the load and can be defined according to needs.Two PEMFC performance functions: the fuel cell voltage and the system-related fuel cell efficiency were optimized using the procedure for practically sized PEMFC stacks of two designs. With respect to the nominal operating conditions defined as optimal for each stack design by its manufacturer, the gains from the optimization procedure were up to over 12% and up to over 7% for the stack voltage and efficiency, respectively. The validation of the procedure involved 5 stack specimens and four laboratories and consistent results were obtained. 相似文献