Matching theory for priority-based cell association in the downlink of wireless small cell networks

The deployment of small cells, overlaid on existing cellular infrastructure, is seen as a key feature in next-generation cellular systems. In this paper, the problem of user association in the downlink of small cell networks (SCNs) is considered. The problem is formulated as a many-to-one matching game in which the users and SCBSs rank one another based on utility functions that account for both the achievable performance, in terms of rate and fairness to cell edge users, as captured by newly proposed priorities. To solve this game, a novel distributed algorithm that can reach a stable matching is proposed. Simulation results show that the proposed approach yields an average utility gain of up to 65% compared to a common association algorithm that is based on received signal strength. Compared to the classical deferred acceptance algorithm, the results also show a 40% utility gain and a more fair utility distribution among the users.Comment: 5 page

Quark-lepton Yukawa ratios and nucleon decay in SU(5) GUTs with type-III seesaw

We consider an extension of the Georgi-Glashow SU(5) GUT model by a 45-dimensional scalar and a 24-dimensional fermionic representation, where the latter leads to the generation of the observed light neutrino masses via a combination of a type I and a type III seesaw mechanism. Within this scenario, we investigate the viability of predictions for the ratios between the charged lepton and down-type quark Yukawa couplings, focusing on the second and third family. Such predictions can emerge when the relevant entries of the Yukawa matrices are generated from single joint GUT operators (i.e. under the condition of single operator dominance). We show that three combinations are viable, (i) $y_\tau/y_b=3/2$, $y_\mu/y_s=9/2$, (ii) $y_\tau/y_b=2$, $y_\mu/y_s=9/2$, and (iii) $y_\tau/y_b=2$, $y_\mu/y_s=6$. We extend these possibilities to three toy models, accounting also for the first family masses, and calculate their predictions for various nucleon decay rates. We also analyse how the requirement of gauge coupling unification constrains the masses of potentially light relic states testable at colliders.Comment: 12 pages + 2 appendices + references, 4 figure

Minimal SU(5)SU(5) GUTs with vectorlike fermions

In this work, we attempt to answer the question, "What is the minimal viable renormalizable $SU(5)$ GUT with representations no higher than adjoints?". We find that an $SU(5)$ model with a pair of vectorlike fermions $5_F+\overline{5}_F$, as well as two copies of $15_H$ Higgs fields, is the minimal candidate that accommodates for correct charged fermion and neutrino masses and can also address the matter-antimatter asymmetry of the universe. Our results show that the presented model is highly predictive and will be fully tested by a combination of upcoming proton decay experiments, collider searches, and low-energy experiments in search of flavor violations. Moreover, we also entertain the possibility of adding a pair of vectorlike fermions $10_F+\overline{10}_F$ or $15_F+\overline{15}_F$ (instead of a $5_F+\overline{5}_F$). Our study reveals that the entire parameter space of these two models, even with minimal particle content, cannot be fully probed due to possible longer proton lifetime beyond the reach of Hyper-Kamiokande.Comment: 27 pages + references, 11 figure

Implications of the zero 1-3 flavour mixing hypothesis: predictions for θPMNS23 and δPMNS

We revisit mixing sum rule relations in the lepton and quark sectors under the assumption that the 1-3 elements of the flavour mixing matrices (VuL, VdL, VeL, VνL) are zero in the flavour basis. We consider the exact relations resulting from the validity of this “zero 1-3 flavour mixing hypothesis” and analyse their implications based on the current experimental data, including effects from RG running. In particular, we analyse how the existing precise measurement of θPMNS13 allows to derive predictions for θPMNS23 in models with constrained θe12. As examples, we calculate the predictions for θPMNS23 which arise in 12 classes of Pati-Salam models and SU(5) GUTs that relate θe12 to θd12. We also derive a novel “lepton phase sum rule”, valid under the additional assumption of small charged lepton mixing contributions. We furthermore point out that, in the context of GUT flavour models, the quark and lepton CP violating phases δCKM and δPMNS can both be predicted from a single imaginary element in the mass matrices

Fully Testable Axion Dark Matter within a Minimal SU(5)SU(5) GUT

We present a minimal Grand Unified Theory model, based on $SU(5)$ gauge symmetry and a global $U(1)$ Peccei-Quinn symmetry, that predicts the existence of an ultralight axion dark matter within a narrow mass range of $m_a\in[0.1,\,4.7]\,$neV. This mass window is determined through an interplay between gauge coupling unification constraints, partial proton decay lifetime limits, and the need to reproduce the experimentally observed fermion mass spectrum. The entire parameter space of the proposed model will be probed through a synergy between several low-energy experiments that look for proton decay (Hyper-Kamiokande), axion dark matter through axion-photon coupling (ABRACADABRA and DMRadio-GUT) and nucleon electric dipole moments (CASPEr Electric).Comment: 28 pages + references, 9 figures, version accepted in PR

Matching with Externalities for Context-Aware User-Cell Association in Small Cell Networks

In this paper, we propose a novel user-cell association approach for wireless small cell networks that exploits previously unexplored context information extracted from users' devices, i.e., user equipments (UEs). Beyond characterizing precise quality of service (QoS) requirements that accurately reflect the UEs' application usage, our proposed cell association approach accounts for the devices' hardware type (e.g., smartphone, tablet, laptop). This approach has the practical benefit of enabling the small cells to make better informed cell association decisions that handle practical device-specific QoS characteristics. We formulate the problem as a matching game between small cell base stations (SBSs) and UEs. In this game, the SBSs and UEs rank one another based on well-designed utility functions that capture composite QoS requirements, extracted from the context features (i.e., application in use, hardware type). We show that the preferences used by the nodes to rank one another are interdependent and influenced by the existing network-wide matching. Due to this unique feature of the preferences, we show that the proposed game can be classified as a many-to-one matching game with externalities. To solve this game, we propose a distributed algorithm that enables the players (i.e., UEs and SBSs) to self-organize into a stable matching that guarantees the required applications' QoS. Simulation results show that the proposed context-aware cell association scheme yields significant gains, reaching up to 52% improvement compared to baseline context-unaware approaches.Comment: 6 pages, 3 figures, conferenc

When Cellular Meets WiFi in Wireless Small Cell Networks

The deployment of small cell base stations(SCBSs) overlaid on existing macro-cellular systems is seen as a key solution for offloading traffic, optimizing coverage, and boosting the capacity of future cellular wireless systems. The next-generation of SCBSs is envisioned to be multi-mode, i.e., capable of transmitting simultaneously on both licensed and unlicensed bands. This constitutes a cost-effective integration of both WiFi and cellular radio access technologies (RATs) that can efficiently cope with peak wireless data traffic and heterogeneous quality-of-service requirements. To leverage the advantage of such multi-mode SCBSs, we discuss the novel proposed paradigm of cross-system learning by means of which SCBSs self-organize and autonomously steer their traffic flows across different RATs. Cross-system learning allows the SCBSs to leverage the advantage of both the WiFi and cellular worlds. For example, the SCBSs can offload delay-tolerant data traffic to WiFi, while simultaneously learning the probability distribution function of their transmission strategy over the licensed cellular band. This article will first introduce the basic building blocks of cross-system learning and then provide preliminary performance evaluation in a Long-Term Evolution (LTE) simulator overlaid with WiFi hotspots. Remarkably, it is shown that the proposed cross-system learning approach significantly outperforms a number of benchmark traffic steering policies

Investigating the RFAM paradox: The pseudoknot explanation

Short abstractInternational audienceIn this short note, we investigate the responsibility of pseudoknotted (PK) foldings in the observed incapacity of an MFE folding method (RNAfold) to predict the structure of certain families of RNA within RFam. We considered the difference Delta in predicted free-energy obtained by respectively considering and omitting PK conformations, which we showed could be reliably used as an indicator for the presence of pseudoknots (84.5% AUC, while 88.3% of PK families have positive values). We furthered our analysis, investigating the top 15 families associated with positive values of Delta associated with non-PK consensus structures in RFAM, and found evidence of the presence of PK in the literature for at least 11 of them. However a large proportion of poorly predicted families remain associated with low Delta values, and additional explanations need be explored for their poor predictions

Real Time Mission Planning

The different advantageous embodiments provide a system comprising a number of computers, a graphical user interface, first program code stored on the computer, and second program code stored on the computer. The graphical user interface is executed by a computer in the number of computers. The computer is configured to run the first program code to define a mission using a number of mission elements. The computer is configured to run the second program code to generate instructions for a number of assets to execute the mission and monitor the number of assets during execution of the mission