Joint Dynamic Radio Resource Allocation and Mobility Load Balancing in 3GPP LTE Multi-Cell Network

Load imbalance, together with inefficient utilization of system resource, constitute major factors responsible for poor overall performance in Long Term Evolution (LTE) network. In this paper, a novel scheme of joint dynamic resource allocation and load balancing is proposed to achieve a balanced performance improvement in 3rd Generation Partnership Project (3GPP) LTE Self-Organizing Networks (SON). The new method which aims at maximizing network resource efficiency subject to inter-cell interference and intra-cell resource constraints is implemented in two steps. In the first step, an efficient resource allocation, including user scheduling and power assignment, is conducted in a distributed manner to serve as many users in the whole network as possible. In the second step, based on the resource allocation scheme, the optimization objective namely network resource efficiency can be calculated and load balancing is implemented by switching the user that can maximize the objective function. Lagrange Multipliers method and heuristic algorithm are used to resolve the formulated optimization problem. Simulation results show that our algorithm achieves better performance in terms of user throughput, fairness, load balancing index and unsatisfied user number compared with the traditional approach which takes resource allocation and load balancing into account, respectively

Development and prediction of scour around offshore wind turbine monopile foundations in ebb and flow tides

\ua9 2024 The Authors. Monopile foundations are commonly used to support offshore wind turbines (OWTs) in nearshore shallow waters, where the periodic ebb and flow of tides can cause severe seabed erosion around these foundations. Accurately predicting the progression of scour depth under these tidal conditions is crucial for the safety of OWTs. While a few empirical formulas for equilibrium scour depth in periodic tides have been proposed, they often overlook the backfilling effects during their derivation. Consequently, these methods fail to predict the progression of scour depth characterized by recurring scouring and backfilling processes. In this study, the scour progression under different tidal patterns, including square tides, symmetrical sinusoidal tides, and asymmetrical sinusoidal tides with various periods, is investigated using numerical methods. It is indicated by the results that deeper scour depths are produced by symmetrical tides compared to asymmetrical tides, while the highest scour depth is observed under square tides, potentially slightly exceeding that under unidirectional currents. Additionally, asymmetric scour depths at the front and back sides of the pile can result from the asymmetry of tides. Although scour progression is affected by tide periods, their impact on the equilibrium scour depth is limited. Furthermore, a new concept called normalized cumulative effective flow intensity is introduced, which plays a primary role in governing equilibrium scour depth. Based on this concept, prediction methods for both equilibrium scour depth and scour progression under sinusoidal tides, which closely resemble natural tidal patterns, are proposed. The accuracy of these methods is validated by experimental data from previous studies. These findings not only provide a method to optimize the design of monopile burial depth but also aid in the development of appropriate maintenance measures to prevent scour-induced damage to OWT foundations over their long lifespans

Leading SU(3)-breaking corrections to the baryon magnetic moments in Chiral Perturbation Theory

We calculate the baryon magnetic moments using covariant Chiral Perturbation Theory ($\chi$PT) within the Extended-on-mass-shell (EOMS) renormalization scheme. By fitting the two available low-energy constants (LECs), we improve the Coleman-Glashow description of the data when we include the leading SU(3) breaking effects coming from the lowest-order loops. This success is in dramatic contrast with previous attempts at the same order using Heavy Baryon (HB) $\chi$PT and covariant Infrared (IR) $\chi$PT. We also analyze the source of this improvement with particular attention on the comparison between the covariant results.Comment: 4 pages, 2 figures, accepted for publication in PR

Spurious Shell Closures in the Relativistic Mean Field Model

Following a systematic theoretical study of the ground-state properties of over 7000 nuclei from the proton drip line to the neutron drip line in the relativistic mean field model [Prog. Theor. Phys. 113 (2005) 785], which is in fair agreement with existing experimental data, we observe a few spurious shell closures, i.e. proton shell closures at Z=58 and Z=92. These spurious shell closures are found to persist in all the effective forces of the relativistic mean field model, e.g. TMA, NL3, PKDD and DD-ME2.Comment: 3 pages, to appear in Chinese Physics Letter

The f0(1370)f_0(1370), f0(1710)f_0(1710), f2(1270)f_2(1270), f2′(1525)f_2'(1525), and K2∗(1430)K_2^*(1430) as dynamically generated states from vector meson - vector meson interaction

We report on some recent developments in understanding the nature of the low-lying mesonic resonances $f_0(1370)$, $f_0(1710)$, $f_2(1270)$, $f_2'(1525)$, and $K_2^*(1430)$. In particular we show that these five resonances can be dynamically generated from vector meson--vector meson interaction in a coupled-channel unitary approach, which utilizes the phenomenologically very successful hidden-gauge Lagrangians to produce the interaction kernel between two vector mesons, which is then unitarized by the Bethe-Salpeter-equation method. The data on the strong decay branching ratios, total decay widths, and radiative decay widths of these five states, and on related $J/\psi$ decay processes can all be well described by such an approach. We also make predictions, compare them with the results of earlier studies, and highlight observables that if measured can be used to distinguish different pictures of these resonances.Comment: 9 pages; Invited talk at workshop CHIRAL'10, Valencia (Spain), June 21-24, 201

Remark on the vectorlike nature of the electromagnetism and the electric charge quantization

In this work we study the structure of the electromagnetic interactions and the electric charge quantization in gauge theories of electroweak interactions based on semi-simple groups. We show that in the standard model of the electroweak interactions the structure of the electromagnetic interactions is strongly correlated to the quantization pattern of the electric charges. We examine these two questions also in all possible chiral bilepton gauge models of the electroweak interactions. In all they we can explain the vectorlike nature of the electromagnetic interactions and the electric charge quantization together demanding nonvanishing fermion masses and the anomaly cancellations.Comment: 17 pages, latex, no figure

Application of the RMF mass model to the r-process and the influence of mass uncertainties

A new mass table calculated by the relativistic mean field approach with the state-dependent BCS method for the pairing correlation is applied for the first time to study r-process nucleosynthesis. The solar r-process abundance is well reproduced within a waiting-point approximation approach. Using an exponential fitting procedure to find the required astrophysical conditions, the influence of mass uncertainty is investigated. R-process calculations using the FRDM, ETFSI-Q and HFB-13 mass tables have been used for that purpose. It is found that the nuclear physical uncertainty can significantly influence the deduced astrophysical conditions for the r-process site. In addition, the influence of the shell closure and shape transition have been examined in detail in the r-process simulations.Comment: to be published in Phys. Rev. C, 22 pages, 9 figure