abstract

Community structure, a critical topological property of complex networks, has recently received extensive and in-depth attention from researchers. Recognizing the non-uniform degree distribution of nodes within network subgraphs, this paper presents a novel algorithm called MD-RWR (Maximum Degree-based Random Walk with Restart) for community detection in complex networks. The proposed algorithm not only excels at identifying overlapping communities but also enhances the objectivity and accuracy of the results. To evaluate its performance, the algorithm is tested on five real-world networks. The experimental results demonstrate its effectiveness in detecting communities, particularly when dealing with overlapping ones. Furthermore, the algorithm surpasses Walktrap, Infomap, LPA, and LPA-S algorithms in terms of modularity and NMI scores, while exhibiting faster execution time compared to these algorithms.

abstract

A recently formulated thermal model for hadron production in heavy-ion collisions in the few-GeV energy regime is combined with the idea that some part of protons and neutrons present in the original thermal system forms deuterons via the coalescence mechanism. Using realistic parametrizations of the freeze-out conditions, which reproduce well the spectra of protons and pions, we make predictions for deuteron transverse-momentum and rapidity spectra. The best agreement with the experimentally known deuteron yield is obtained if the freeze-out temperature is relatively high and, accordingly, the system size at freeze-out is rather small. In addition, the standard Gaussian distribution of the relative distance between nucleons is replaced by the distribution resulting from their independent and approximately uniform production inside the initial thermal system.

abstract

The skin effect is a significant feature of non-Hermitian systems and is caused by the global non-Hermitian nature of the system. Recent studies have discovered a scale-free localized eigenstate induced by a local non-Hermitian term. We constructed a uniform dimer model with an asymmetric transition embedded at the boundary. A change in the boundary parameter can cause a phase transition from the real energy level to the complex energy level, resulting in a scale-free state. Moreover, we introduce the inverse participation rate and the position of the center of mass to determine the local situation of the eigenstate. Interestingly, at the phase boundary, all the eigenstates of the system are observed to be scale-free localized. This phenomenon causes the evolution of the wave packet dynamics of the system to exhibit attractive power-law behavior and possesses EP-like characteristics. This interesting property provides a new possible realization of optical devices. Finally, we also present the circuit diagram of the system implementation for experimental observation.