325,020 research outputs found
Replication data for: Anti-Muslim Voting and Media Coverage of Immigrant Crimes
No full textData and code of “Anti-Muslim Voting and Media Coverage of Immigrant Crimes”, M. Couttenier, S. Hatte, M. Thoenig, S. Vlachos
Lean thinking in the food supply chain: an action case research
No full textThe purpose of the study is to examine the adoption of lean tools in food supply chains as well as to understand how small and medium companies (SMEs) can implement lean tools in order to develop a lean action plan designed for SMEs. A case study research is used in the present study of a UK tea company. An action research approach was adopted to study the lean process and diagnosis of problems occurred during implementation (Vlachos, 2011). The present study developed a lean action plan needs to include the following steps: Re-Define Value, Map Value Streams, Detect Waste, Lean the Production Operations, Ideal State of Production Operations, and Develop a Pull Strategy. The findings derived from this research would facilitate practitioners in undertaking lean endeavours. The potential contribution of leaning food small and medium companies can be enormous given the percentage of food waste across supply chains (Vlachos, 2004a, Vlachos, 2004b). The contribution of this study is threefold: (a) it offers insights on a lean action plan for small and medium companies. (b) it sheds light on how lean thinking can be applied in the food sector (c) it tests a unique reflecting methodology using action case research to gather, interpret, and develop reflective learning
44. Vlachos (A. S.). Partialités chez Thucydide
No full textLachenaud Guy. 44. Vlachos (A. S.). Partialités chez Thucydide . In: Revue des Études Grecques, tome 83, fascicule 394-395, Janvier-juin 1970. pp. 258-259
Energy-Efficiency Maximization of Hybrid Massive MIMO Precoding with Random-Resolution DACs via RF Selection Matlab Software
No full textThis zip file contains MATLAB scripts and key simulation results for the following paper:
Energy-Efficiency Maximization of Hybrid Massive MIMO Precoding with
Random-Resolution DACs via RF Selection, by Evangelos Vlachos and John
Thompson, To Appear in IEEE Transactions on Wireless Communications.
The code has been tested successfully on MATLAB Release 2019A using the CVX toolbox.
The code licence terms can be found in the file LICENCE and full details can be found in the file README
Replication package for: "Populist Persuasion in Electoral Campaigns: Evidence from Bryan´s Unique Whistle-Stop Tour"
No full textReplication package for: Buggle, J.C, and Vlachos, S. (2022). ‘Populist Persuasion in Electoral Campaigns: Evidence from Bryan’s Unique Whistle-Stop Tour’. The Economic Journal
EXPERIMENTAL INVESTIGATION ON PERFORMANCE AND EMISSIONS OF AN AUTOMOTIVE DIESEL ENGINE FUELLED WITH BIOFUELS
No full textBiodiesel is the biofuel most commonly used in Europe, covering approximately 80% of the biofuel market. However, the relationship between biofuel industry and food prices push towards the adoption of new generation biodiesels which could minimize the impact of biofuels production on human food chain. Biodiesel sourced from non-edible seed oils like Jatropha Curcas could therefore be a viable solution for biodiesel production, since allows green cover to wasteland. More recently, also Hydrotreated Vegetable Oil (HVO), obtained by means of a refinery-based process that converts vegetable oils into paraffinic hydrocarbons, has been gaining an increasing attention. The effects of using high percentage blends of ultra low sulphur diesel and biofuels (FAME and HVO) in a Euro 5 small displacement passenger car diesel engine on combustion process, full load performance and part load emissions have been evaluated in this work. Moreover, a characterization of Particulate Matter (PM) in terms of mass, chemical composition and particles number and size distribution was assessed as well. The impacts that fuels with different physical and chemical properties may have on injection, combustion and on ECU calibration process were evaluated by means of specific tests campaign involving different injection timings under part load operation. Results highlighted that the implementation of models for blending detection, on engines ECUs, could be of crucial importance for a wider usage of biofuels in transportation sector. In addition, the effects on engine torque were analyzed, for both a standard ECU calibration (i.e. without any special tuning for the different fuel characteristics) and for a specifically adjusted ECU calibration obtained by properly increasing the injected fuel quantities to compensate for the lower Lower Heating Value (LHV) of the biofuels: with the latter, the same torque levels measured under diesel operation could be observed with the biodiesel too, with lower smoke levels, thus highlighting the potential for maintaining the same level of performance while achieving substantial emissions benefits. Moreover, the effects of biodiesel blends on brake specific fuel consumption and on engine-out exhaust emissions (CO2, CO, HC, NOx and smoke) were also evaluated at several part load operating conditions, representative of the New European Driving Cycle (NEDC). Both standard and specific calibrations were evaluated, highlighting an average rise of fuel consumption in good agreement with LHV decrease, at same fuel conversion efficiency and CO2 emissions. A decrease of NOx emissions when using a specifically adjusted engine calibration, along with a considerable smoke emission reduction were observed as well. Due to increasing concerns about the hazardous effects that particulate matter could have on human health, PM emissions were evaluated under normal engine operating mode at part load operation. PM gravimetric analysis at medium and high load operating points showed a good correlation with soot measurements carried out by means of standard laboratory equipment (i.e. smokemeters). On the contrary, at low loads, the same instrument underestimated the Soluble Organic Fraction (SOF) fraction of PM especially when biofuel was used. Thermo-gravimetric analysis confirmed the outcomes from gravimetric analysis: the significance of standard measurements which are commonly carried out during the engine calibration activity should be carefully considered when biofuels are adopted. Finally, the assessment of the toxicological potential of PM when HVO and Rapeseed Methyl Ester (RME) were used was carried out. Results highlighted that PM from HVO had a higher mutagenic effect respect to PM emissions obtained with other fuel
Investigating e-business practices in tourism :a comparative analysis of three countries
No full textThis study examined the behaviour of tourist companies in relation to the adoption of e-business technologies and applications. The study aimed to identify groups of companies with homogenous behaviour among three European countries (Greece, Portugal and Norway). Based on data from a European survey, the study employed two-step cluster analysis which revealed 14 clusters of common behaviour (five clusters in Greece, five in Portugal and four in Norway). These clusters were named as: Leaders’ ‘Technology Experts’, ‘Fast Adopters’ ‘Beginners’, ‘Late Adopters’. In Norway, the group ‘Late Adopters’ also included companies characterised as ‘Beginners’ in the other two countries. We suggest further investigation among European countries in order to reveal more groups of similar behaviour toward e-business adoption
Light-front approach to relativistic electrodynamics
No full textWe illustrate how our recent light-front approach simplifies relativistic
electrodynamics with an electromagnetic (EM) field that is the sum
of a (even very intense) plane travelling wave and a
static part ; it adopts the light-like coordinate
instead of time as an independent variable. This can be
applied to several cases of extreme acceleration, both in vacuum and in a cold
diluted plasma hit by a very short and intense laser pulse (slingshot effect,
plasma wave-breaking and laser wake-field acceleration, etc.)Comment: Latex file, 20 pages, 7 figures. To appear in the Proceedings of the
"9th International Conference on Mathematical Modeling in Physical Sciences",
September 7-10, 2020 (held on-line because of the Covid19 pandemic
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