856 research outputs found
Accidental matter at the LHC
We classify weak-scale extensions of the Standard Model which automatically
preserve its accidental and approximate symmetry structure at the
renormalizable level and which are hence invisible to low-energy indirect
probes. By requiring the consistency of the effective field theory up to scales
of 10^15 GeV and after applying cosmological constraints, we arrive at a finite
set of possibilities that we analyze in detail. One of the most striking
signatures of this framework is the presence of new charged and/or colored
states which can be efficiently produced in high-energy particle colliders and
which are stable on the scale of detectors.Comment: 55 pages, 13 figure
Current, Projected Performance and Costs of Thermal Energy Storage
The technology for storing thermal energy as sensible heat, latent heat, or thermochemical energy has greatly evolved in recent years, and it is expected to grow up to about 10.1 billion US dollars by 2027. A thermal energy storage (TES) system can significantly improve industrial energy efficiency and eliminate the need for additional energy supply in commercial and residential applications. This study is a first-of-its-kind specific review of the current projected performance and costs of thermal energy storage. This paper presents an overview of the main typologies of sensible heat (SH-TES), latent heat (LH-TES), and thermochemical energy (TCS) as well as their application in European countries. With regard to future challenges, the installation of TES systems in buildings is being implemented at a rate of 5%; cogeneration application with TES is attested to 10.2%; TES installation in the industry sector accounts for 5% of the final energy consumption. From the market perspective, the share of TES is expected to be dominated by SH-TES technologies due to their residential and industrial applications. With regard to the cost, the SH-TES system is typically more affordable than the LH-TES system or the TCS system because it consists of a simple tank containing the medium and the charging/discharging equipment
Renewable sources urban cells microgrid. A case study
Nowadays, microgrid technologies play a relevant role in the research field as well as in the commercial market. The opportunity to provide electricity in wide areas without using centralized electrical infrastructure networks is a reliable key for achieving the European Union sustainability goals. In this regard, the proposed research aims at describing an electric microgrid configuration powered by a photovoltaic system, supplying three school buildings located in the center of Italy. Additionally, the resilience theme is deeply investigated, analyzing the use of an emergency generator system (EGS) in case of electric grid blackouts. MATLAB/Simulink was chosen to simulate the users’ energy demand as well as to calculate the microgrid performance. Results show that almost the total consumption of the microgrid is covered by the photovoltaic system, and the use of an EGS allows energy resilience and moderate economic savings for the communit
Static and dynamic thermal properties of construction components: A comparison in idealized and experimental conditions using lumped parameter models
The U values assumptions for construction components represent a significant source of uncertainty when estimating the energy performance of buildings. This uncertainty affects decision-making processes in multiple ways, from policy making to design of new and refurbished buildings. The correct estimation of both static (e.g. thermal transmittance) and dynamic thermal properties is crucial for quality assurance in building performance assessment. Further, while today many sophisticated simulators are available for building performance modelling, lumped parameter models can help reducing computational time for parametric simulation or optimization and enable inverse estimation of lumped thermal characteristics. A lumped parameter approach for construction components is proposed, for example, by the ISO 52016-1:2017 norm, introducing simplifications that are intrinsically dependent on component's stratigraphy. This approach complements ISO 13786:2017 norm method, which is limited to steady-state periodic temperature and heat flux boundary conditions. In this research we consider these two different approaches, detailed and lumped modelling, comparing them first in idealized conditions and then in experimental conditions to analyse the robustness of methods
Hierarchical Soft Terms and Flavor Physics
We study the framework of hierarchical soft terms, in which the first two
generations of squarks and sleptons are heavier than the rest of the
supersymmetric spectrum. This scheme gives distinctive predictions for the
pattern of flavor violations, which we compare to the case of nearly degenerate
squarks. Experiments in flavor physics have started to probe the most
interesting parameter region, especially in transitions,
where hierarchical soft terms can predict a phase of mixing much larger
than in the Standard Model.Comment: 21p
Explainable Artificial Intelligence in communication networks: A use case for failure identification in microwave networks
Artificial Intelligence (AI) has demonstrated superhuman capabilities in solving a significant number of tasks, leading to widespread industrial adoption. For in-field network-management application, AI-based solutions, however, have often risen skepticism among practitioners as their internal reasoning is not exposed and their decisions cannot be easily explained, preventing humans from trusting and even understanding them. To address this shortcoming, a new area in AI, called Explainable AI (XAI), is attracting the attention of both academic and industrial researchers. XAI is concerned with explaining and interpreting the internal reasoning and the outcome of AI-based models to achieve more trustable and practical deployment. In this work, we investigate the application of XAI for network management, focusing on the problem of automated failure-cause identification in microwave networks. We first introduce the concept of XAI, highlighting its advantages in the context of network management, and we discuss in detail the concept behind Shapley Additive Explanations (SHAP), the XAI framework considered in our analysis. Then, we propose a framework for a XAI-assisted ML-based automated failure-cause identification in microwave networks, spanning model's development and deployment phases. For the development phase, we show how to exploit SHAP for feature selection and how to leverage SHAP to inspect misclassified instances during model's development process, and how to describe model's global behavior based on SHAP's global explanations. For the deployment phase, we propose a framework based on predictions uncertainty to detect possibly wrong predictions that will be inspected through XAI
Missense PDSS1 mutations in CoenzymeQ10 synthesis cause optic atrophy and sensorineural deafness
CoenzymeQ10 is one of the main cellular antioxidants and an essential lipid involved in numerous cell reactions, such as energy production and apoptosis modulation. A large number of enzymes are involved in CoQ10 biosynthesis. Mutations in the genes encoding for these enzymes cause a CoQ10 deficiency, characterized by neurological and systemic symptoms. Here we describe two young sisters with sensorineural deafness followed by optic atrophy, due to a novel homozygous pathogenic variant in PDSS1. The visual system seems to be mainly involved when the first steps of CoQ10 synthesis are impaired (PDSS1, PDSS2, and COQ2 deficiency)
Gravitino Dark Matter in Tree Level Gauge Mediation with and without R-parity
We investigate the cosmological aspects of Tree Level Gauge Mediation, a
recently proposed mechanism in which the breaking of supersymmetry is
communicated to the soft scalar masses by extra gauge interactions at the tree
level. Embedding the mechanism in a Grand Unified Theory and requiring the
observability of sfermion masses at the Large Hadron Collider, it follows that
the Lightest Supersymmetric Particle is a gravitino with a mass of the order of
10 GeV. The analysis in the presence of R-parity shows that a typical Tree
Level Gauge Mediation spectrum leads to an overabundance of the Dark Matter
relic density and a tension with the constraints from Big Bang Nucleosynthesis.
This suggests to relax the exact conservation of the R-parity. The underlying
SO(10) Grand Unified Theory together with the bounds from proton decay provide
a rationale for considering only bilinear R-parity violating operators. We
finally analyze the cosmological implications of this setup by identifying the
phenomenologically viable regions of the parameter space.Comment: 28 pages, 5 figures. References added. To appear in JHE
Extended Tree-Level Gauge Mediation
Tree-level gauge mediation (TGM) is a scenario of SUSY breaking in which the
tree-level exchange of heavy (possibly GUT) vector fields generates
flavor-universal sfermion masses. In this work we extend this framework to the
case of E_6 that is the natural extension of the minimal case studied so far.
Despite the number of possible E_6 subgroups containing G_SM is large (we list
all rank 6 subgroups), there are only three different cases corresponding to
the number of vector messengers. As a robust prediction we find that sfermion
masses are SU(5) invariant at the GUT scale, even if the gauge group does not
contain SU(5). If SUSY breaking is mediated purely by the U(1) generator that
commutes with SO(10) we obtain universal sfermion masses and thus can derive
the CMSSM boundary conditions in a novel scenario.Comment: 22 pages, 2 figures, 3 table
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