GEM-E3 Model Documentation

The computable general equilibrium model GEM-E3 has been used in a large set of climate policy applications supporting Commission policy proposals during the last decade, as well as in other environmental and economic policy areas. It can be considered a multi-purpose macroeconomic model, designed to estimate the effects of sector-specific policies on the economy as a whole. The main purpose of this publication is to provide extensive documentation of the model's equations and its underlying databases, in order to offer to the broader audience an accurate description of the model characteristics.JRC.J.1-Economics of Climate Change, Energy and Transpor

Interaction of consumer preferences and climate policies in the global transition to low-carbon vehicles

Burgeoning demands for mobility and private vehicle ownership undermine global efforts to reduce energy-related greenhouse gas emissions. Advanced vehicles powered by low-carbon sources of electricity or hydrogen offer an alternative to conventional fossil-fuelled technologies. Yet, despite ambitious pledges and investments by governments and automakers, it is by no means clear that these vehicles will ultimately reach mass-market consumers. Here, we develop state-of-the-art representations of consumer preferences in multiple, global energy- economy models, specifically focusing on the non-financial preferences of individuals. We employ these enhanced model formulations to analyse the potential for a low-carbon vehicle revolution up to mid-century. Our analysis shows that a diverse set of measures targeting vehicle buyers is necessary for driving widespread adoption of clean technologies. Carbon pricing alone is insufficient for bringing low-carbon vehicles to mass market, though it can certainly play a supporting role in ensuring a decarbonised energy supply

Distributed System for Job Scheduling in a GPU Cluster via Remote Code Execution

83 σ.Οι GPUs έχουν γίνει πλέον κυρίαρχες στον τομέα της υπολογιστικής τεχνολογίας. Η καταλληλότητα τους και η μεγάλη ικανότητα παραλληλοποίησης που προσφέρουν τις έχουν καταστήσει σημαντικότατους υπολογιστικούς πόρους. Κύρια εφαρμογή τους είναι σε επιστημονικές εφαρμογές, που από μόνες τους έχουν τεράστιες ανάγκες για υπολογιστική ισχύ αλλά και μεγάλες δυνατότητες παραλληλοποίησης. Για το σκοπό αυτό έχουν δημιουργηθεί πλατφόρμες που να υποστηρίζουν το λεγόμενο General Purpose Graphics Processing (GPGPU), που επιτρέπει πλέον στην GPU να εκτελεί υπολογισμούς σε εφαρμογές γενικότερου σκοπού, σε αντίθεση μέχρι τώρα που ειδικευόταν σε γραφικές εφαρμογές. Να σημειωθεί εδώ ότι σε καμία περίπτωση η GPU δεν αντικαθιστά την CPU. Αρχιτεκτονικοί λόγοι την περιορίζουν από το να χρησιμοποιηθεί ως η κύρια μονάδα επεξεργασίας ενός συστήματος. Αυτό που κάνει είναι απλώς να επιταχύνει συγκεκριμένες εφαρμογές της CPU. Η ανάγκη για υπολογιστική ισχύ είναι πλέον τόσο μεγάλη, ώστε κατασκευάζονται ολόκληρες συστοιχίες (clusters) υπολογιστών βασισμένες σε GPUs (GPU Clusters). Προφανώς χρειάζεται ειδικό Hardware , αλλά και λογισμικό , για τη σωστή διαχείριση ενός τέτοιου cluster. Για το μεν Hardware υπάρχουν εταιρείες που κατασκευάζουν ισχυρούς επεξεργαστές γραφικών και εξοπλίζουν τα datacenters για το σκοπό αυτό. Για το δε software, απαιτούνται κατάλληλα συστήματα διαχείρισης ώστε να εκμεταλλεύονται όσο το δυνατόν περισσότερο την επεξεργαστική ισχύ των GPUs στις συστοιχίες υπολογιστών. Το πρόβλημα είναι ότι η διαθεσιμότητα GPUs στους κόμβους των συστοιχιών αυτών είναι σχεδόν πάντα περιορισμένη λόγω του κόστους. Η παρούσα διπλωματική παρουσιάζει το σύστημα rGPU, ένα σύστημα διαχείρισης του cluster το οποίο αναλαμβάνει την διαφανή εκτέλεση προγραμμάτων επιταχυμένων από GPUs σε κόμβους οι οποίοι δεν τις διαθέτουν. Αρχικά γίνεται μια εκτενής ανασκόπηση της βιβλιογραφίας πάνω στον συγκεκριμένο τομέα, έπειτα παρουσιάζεται το προτεινόμενο σύστημα, περιγράφεται αναλυτικά η σχεδίαση και η υλοποίηση του και τέλος αξιολογείται με βάση συγκεκριμένα σενάρια χρήσης.GPUs have become a dominant feature in the field of computer technology. Their always growing scalability and computational power are beginning to classify them as first-class computing resources. Their main application is in the field of science, where applications need huge processing capabilities and offer a huge level of parallelization. For this purpose, many platforms have been created to support the so-called General Purpose GPU Computing (GPGPU), that enables graphic processors to carry out general purpose calculations, as opposed to the past when they were only used for graphics rendering. However, in no way can the GPU fully replace the CPU. The GPU is a co-processor that accelerates specific parts of a program and architectural reasons prevent it from being used as the primary processing unit of a system. This need for computational power is so great that GPUs are being installed in High Performance Clusters and Supercomputers. Of course, special hardware, software and technical expertise are required in order to fully utilize these co-processors. As far as hardware is concerned there are many companies that manufacture these powerful special processors. As for the software, apart from the programming tools needed to utilize the GPUs, complex cluster management systems are needed in order to co-ordinate the processing. The problem so far is that, because of the cost, the availability of GPUs in High Performance clusters is limited. The purpose of this thesis is to introduce a new cluster management system, the purpose of which is to utilize the GPUs in the cluster as much as possible. For this purpose it uses an already developed and optimized system called rCUDA, that enables the remote execution of CUDA programs from nodes not equipped with a GPU. First, an extensive review of the state-of-the-art methods in parallel processing is provided and then the new system is being proposed along with detailed information about its architecture, its implementation and its evaluation process.Αντώνιος Π. Καρκατσούλη

RESEARCH ON THE DYNAMICS OF LITHUANIAN STATE REVENUE AND PREFERENCES FOR EXPENDITURE ALLOCATION

The article analyses revenue and expenditure on the national budget of Lithuania and looks at their dynamics and structure. First, the paper is aimed at naming the main sources of revenue as well as the preferential areas of financing. Second, it is also sought to disclose the objective principles of allocating budget appropriation. To achieve the goal, the correlation between preferences in government activity and expenditure allocation was investigated. The conducted research employs ranging and correlational analysis. Since the formation of a bigger budget leads to an increased appropriation of all functional areas, structural data were analysed thus enabling to more soundly determine whether the distinction of a functional area, as the preferential one, has an influence on its greater significance in the overall system of the national budget. After making the study, no possibility of asserting that a distinction of the preferential functional area is related to its preferential financing exists. In order to summarize the obtained results, it could be claimed that the allocation of resources accumulated by the state would be more substantiated if we related it more with activity priorities of the Government. This would lead to higher objectivity when taking decisions on public administration

Decomposing passenger transport futures: Comparing results of global integrated assessment models

International audienceThe transport sector is growing fast in terms of energy use and accompanying greenhouse gas emissions. Integrated assessment models (IAMs) are used widely to analyze energy system transitions over a decadal time frame to help inform and evaluating international climate policy. As part of this, IAMs also explore pathways of decarbonizing the transport sector. This study quantifies the contribution of changes in activity growth, modal structure, energy intensity and fuel mix to the projected passenger transport carbon emission pathways. The Laspeyres index decomposition method is used to compare results across models and scenarios, and against historical transport trends. Broadly-speaking the models show similar trends, projecting continuous transport activity growth, reduced energy intensity and in some cases modal shift to carbon-intensive modes - similar to those observed historically in a business-as-usual scenario. In policy-induced mitigation scenarios further enhancements of energy efficiency and fuel switching is seen, showing a clear break with historical trends. Reduced activity growth and modal shift (towards less carbon-intensive modes) only have a limited contribution to emission reduction. Measures that could induce such changes could possibly complement the aggressive, technology switch required in the current scenarios to reach internationally agreed climate targets

Integrated assessment model diagnostics: Key indicators and model evolution

Integrated assessment models (IAMs) form a prime tool in informing about climate mitigation strategies. Diagnostic indicators that allow comparison across these models can help describe and explain differences in model projections. This increases transparency and comparability. Earlier, the IAM community has developed an approach to diagnose models (Kriegler (2015 Technol. Forecast. Soc. Change 90 45-61)). Here we build on this, by proposing a selected set of well-defined indicators as a community standard, to systematically and routinely assess IAM behaviour, similar to metrics used for other modeling communities such as climate models. These indicators are the relative abatement index, emission reduction type index, inertia timescale, fossil fuel reduction, transformation index and cost per abatement value. We apply the approach to 17 IAMs, assessing both older as well as their latest versions, as applied in the IPCC 6th Assessment Report. The study shows that the approach can be easily applied and used to indentify key differences between models and model versions. Moreover, we demonstrate that this comparison helps to link model behavior to model characteristics and assumptions. We show that together, the set of six indicators can provide useful indication of the main traits of the model and can roughly indicate the general model behavior. The results also show that there is often a considerable spread across the models. Interestingly, the diagnostic values often change for different model versions, but there does not seem to be a distinct trend

Integrated assessment model diagnostics

| openaire: EC/H2020/821124/EU//NAVIGATEIntegrated assessment models (IAMs) form a prime tool in informing about climate mitigation strategies. Diagnostic indicators that allow comparison across these models can help describe and explain differences in model projections. This increases transparency and comparability. Earlier, the IAM community has developed an approach to diagnose models (Kriegler (2015 Technol. Forecast. Soc. Change 90 45-61)). Here we build on this, by proposing a selected set of well-defined indicators as a community standard, to systematically and routinely assess IAM behaviour, similar to metrics used for other modeling communities such as climate models. These indicators are the relative abatement index, emission reduction type index, inertia timescale, fossil fuel reduction, transformation index and cost per abatement value. We apply the approach to 17 IAMs, assessing both older as well as their latest versions, as applied in the IPCC 6th Assessment Report. The study shows that the approach can be easily applied and used to indentify key differences between models and model versions. Moreover, we demonstrate that this comparison helps to link model behavior to model characteristics and assumptions. We show that together, the set of six indicators can provide useful indication of the main traits of the model and can roughly indicate the general model behavior. The results also show that there is often a considerable spread across the models. Interestingly, the diagnostic values often change for different model versions, but there does not seem to be a distinct trend.Peer reviewe