Rezultati ispitivanja SHASHLIK elektromagnetskog kalorimetra

In 1994, extensive tests were carried out to evaluate shashlik prototype calorimeter as a candidate for the electromagnetic calorimeter (ECAL) for the Compact Muon Solenoid (CMS) detector. The measured energy resolution is characterized by a stochastic term of 8.5%/ √ E, a noise term of 0.33/ E and a constant term of 0.5% (E in GeV). Reproducibility of performance of the towers and the uniformity of the calorimeter response have been studied across a large 25 cm × 25 cm area. Effects of radiation damage on the shashlik tower have also been studied.Sveučilište u Splitu, kao član CMS kolaboracije, sudjeluje u razvoju olovno/scintilacijskog elektromagnetskog kalorimetra ”sandwich”-tipa (shashlik), u okviru RD36 projekta. Tijekom 1994. provedeni su detaljni eksperimentalni testovi svojstava prototip-tornjeva shashlik kalorimetra, kao jednog od kandidata za elektromagnetski kalorimetar u CMS detektoru na LHC-u. Izmjereno energijsko razlučivanja određeno je stohastičkim članom iznosa 8.5%/ √ E, šumom iznosa 0.33/E, te konstantnim članom iznosa 0.5% (E u GeV). Razmatrana je reproducibilnost proizvodnje tornjeva jednakih svojstava, uniformnost odziva kalorimetra na površini 25 cm ×25 cm, te kutno razlučivanje. Procijenjen je i utjecaj radijacijskih oštećenja na shashlik tornjeve

Rezultati ispitivanja SHASHLIK elektromagnetskog kalorimetra

In 1994, extensive tests were carried out to evaluate shashlik prototype calorimeter as a candidate for the electromagnetic calorimeter (ECAL) for the Compact Muon Solenoid (CMS) detector. The measured energy resolution is characterized by a stochastic term of 8.5%/ √ E, a noise term of 0.33/ E and a constant term of 0.5% (E in GeV). Reproducibility of performance of the towers and the uniformity of the calorimeter response have been studied across a large 25 cm × 25 cm area. Effects of radiation damage on the shashlik tower have also been studied.Sveučilište u Splitu, kao član CMS kolaboracije, sudjeluje u razvoju olovno/scintilacijskog elektromagnetskog kalorimetra ”sandwich”-tipa (shashlik), u okviru RD36 projekta. Tijekom 1994. provedeni su detaljni eksperimentalni testovi svojstava prototip-tornjeva shashlik kalorimetra, kao jednog od kandidata za elektromagnetski kalorimetar u CMS detektoru na LHC-u. Izmjereno energijsko razlučivanja određeno je stohastičkim članom iznosa 8.5%/ √ E, šumom iznosa 0.33/E, te konstantnim članom iznosa 0.5% (E u GeV). Razmatrana je reproducibilnost proizvodnje tornjeva jednakih svojstava, uniformnost odziva kalorimetra na površini 25 cm ×25 cm, te kutno razlučivanje. Procijenjen je i utjecaj radijacijskih oštećenja na shashlik tornjeve

EEDI kao mjera energetske učinkovitosti broda

U cilju poticanja razvoja suvremenih tehnoloških rješenja koja doprinose poboljšavanju energetske učinkovitosti i unapređenju zaštite okoliša IMO Rezolucijom MEPC.203(62) donosi izmjene MARPOL-a, Prilog VI. Izmjene se odnose na obavezu uključivanja pravila za utvrđivanje i kontrolu energetske učinkovitosti u nacionalna pravila registara, kojima se propisuje obavezna primjena projektnog indeksa energetske učinkovitosti (EEDI) i brodskog plana upravljanja energetskom učinkovitosti (SEEMP). Dosadašnje iskustvo u primjeni formule za odreñivanje EEDI-a pokazuje da je potrebno prilagođavati vrijednosti i dopunjavati broj utjecajnih faktora ovisno o tipovima brodova i o njihovim specifičnim projektnim i eksploatacijskim značajkama. U radu su analizirani nedostaci primjene trenutno važeće (strukture) formule za odreñivanje EEDI-a. Za ro-pax brodove su posebno analizirani parametri za koje se smatra da značajnije utječu na vrijednost EEDI-a, a proizlaze iz različitih specifičnih projektnih i eksploatacijskih značajki tih brodova

Hibridni energetski sustav malog putničkog broda

Osnovni ciljevi razvoja modernih brodskih energetskih sustava su povećanje energetske učinkovitosti i pouzdanosti te ispunjavanje kriterija ekološke prihvatljivosti. Kriterij ekološke prihvatljivosti je posebno izražen kod putničkih brodova, trajekata, brodova za unutarnju plovidbu, itd. gdje problemi utjecaja na okoliš postaju sve važniji projektni kriterij. U članku je prikazan idejni projekt hibridnog energetskog sustava višenamjenskog putničkog broda, koji se sastoji od dizelskog motora, gorivnog članka i baterije kao izvora električne energije. Za tipične režime plovidbe odabranog broda određena je energetska bilanca. Uz analizu energetske učinkovitosti i ekološke prihvatljivosti, zaključno su istaknute prednosti i nedostaci predloženog rješenja u odnosu na klasične izvedbe brodskih energetskih sustava sa smjernicama za daljnja poboljšanja

In-Domain Self-Supervised Learning Can Lead to Improvements in Remote Sensing Image Classification

Self-supervised learning (SSL) has emerged as a promising approach for remote sensing image classification due to its ability to leverage large amounts of unlabeled data. In contrast to traditional supervised learning, SSL aims to learn representations of data without the need for explicit labels. This is achieved by formulating auxiliary tasks that can be used to create pseudo-labels for the unlabeled data and learn pre-trained models. The pre-trained models can then be fine-tuned on downstream tasks such as remote sensing image scene classification. The paper analyzes the effectiveness of SSL pre-training using Million AID - a large unlabeled remote sensing dataset on various remote sensing image scene classification datasets as downstream tasks. More specifically, we evaluate the effectiveness of SSL pre-training using the iBOT framework coupled with Vision transformers (ViT) in contrast to supervised pre-training of ViT using the ImageNet dataset. The comprehensive experimental work across 14 datasets with diverse properties reveals that in-domain SSL leads to improved predictive performance of models compared to the supervised counterparts

A novel approach towards more realistic energy efficiency regulations for tankers

The Energy Efficiency Design Index (EEDI) regulation introduced by the Marine Environment Protection Committee (MEPC) within International Maritime Organization (IMO) has the aim to improve new vessel designs in order to reduce the shipping sector CO2 emissions. But the regulation, in its current form, does not effectively assess the ships energy performance. As the Attained EEDI calculation considers only a single operating point (75% main engine power, fully laden condition, calm seas, constant auxiliary engines power) and does not take into account the ship thermal power system, improvements of the ship energy efficiency cannot be assessed realistically. In this paper, a new approach is proposed to more realistically determine the energy efficiency for tankers. The proposed approach represents better the ship entire operating envelope whilst considering the major ship energy consumers. Thus, a better insight in the ship power system performance is provided allowing for the identification of operating points with low operational efficiency. If implemented for regulatory purposes, this approach could yield a higher impact on the tanker’s power plant design leading to the increase of the ship energy efficiency, the reduction of the GHG emissions and the ship environmental footprint improvement

Metric perturbations in Noncommutative Gravity

We use the framework of Hopf algebra and noncommutative differential geometry to build a noncommutative (NC) theory of gravity in a bottom-up approach. Noncommutativity is introduced via deformed Hopf algebra of diffeomorphisms by means of a Drinfeld twist. The final result of the construction is a general formalism for obtaining NC corrections to the classical theory of gravity for a wide class of deformations and a general background. This also includes a novel proposal for noncommutative Einstein manifold. Moreover, the general construction is applied to the case of a linearized gravitational perturbation theory to describe a NC deformation of the metric perturbations. We specifically present an example for the Schwarzschild background and axial perturbations, which gives rise to a generalization of the work by Regge and Wheeler. All calculations are performed up to first order in perturbation of the metric and noncommutativity parameter. The main result is the noncommutative Regge-Wheeler potential. Finally, we comment on some differences in properties between the Regge-Wheeler potential and its noncommutative counterpart.Comment: 23 pages, 3 figure

Towards gravitational QNM spectrum from quantum spacetime

The effective potential for the axial mode of gravitational wave on noncommutative Schwarzschild background is presented. Noncommutativity is introduced via deformed Hopf algebra of diffeomorphisms by means of a semi-Killing Drinfeld twist. The analysis is performed up to the first order in perturbation of the metric and noncommutativity parameter. This results in a modified Regge-Wheeler potential with the strongest differences in comparison to the classical Regge-Wheeler potential being near the horizon.Comment: 9 pages, 1 figure; presented and prepared for "the XII. International Symposium on Quantum Theory and Symmetries" (QTS12) and "XXVII. International Conference on Integrable Systems and Quantum Symmetries" (ISQS27),July 24-28 2023., Pragu