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Influence maximization (IM) is a crucial optimization task related to analyzing complex networks in the real world, such as social networks, disease propagation networks, and marketing networks. Publications to date about the IM problem focus mainly on graphs, which fail to capture high-order interaction relationships from the real world. Therefore, the use of hypergraphs for addressing the IM problem has been receiving increasing attention. However, identifying the most influential nodes in hypergraphs remains challenging, mainly because nodes and hyperedges are often strongly coupled and correlated. In this paper, to effectively identify the most influential nodes, we first propose a novel hypergraph-independent cascade model that integrates the influences of both node and hyperedge failures. Afterward, we introduce genetic algorithms (GA) to identify the most influential nodes that leverage hypergraph collective influences. In the GA-based method, the hypergraph collective influence is effectively used to initialize the population, thereby enhancing the quality of initial candidate solutions. The designed fitness function considers the joint influences of both nodes and hyperedges. This ensures the optimal set of nodes with the best influence on both nodes and hyperedges to be evaluated accurately. Moreover, a new mutation operator is designed by introducing factors, i.e., the collective influence and overlapping effects of nodes in hypergraphs, to breed high-quality offspring. In the experiments, several simulations on both synthetic and real hypergraphs have been conducted, and the results demonstrate that the proposed method outperforms the compared methods.

The objective of this study is to design and optimize metamaterial, especially those functioning in the near-IR and visible light range, with alloy wire array in a dielectric material to be fabricated by thermal drawing, overcoming the long time challenge in scalable fabrication of optical metamaterials. The feature size, wire diameter, of the metamaterial made of the wire-array structure, is demanded to be less than one-fifth of the incident light wavelength. Therefore, metal wire arrays with a wire diameter and a pitch size both less than 500 nm are required. This type of metamaterial, due to its three dimensional nature, is very hard to fabricate using conventional nanofabrication technologies. Thermal drawing technology is widely considered to be the most suitable method for fabricating this type of particular structures. Yet long, continuous metal wires with a diameter less than 500 nm have not been achieved by thermal drawing, due to an unavoidable instability in molten metal, a fluid with low viscosity and a high interfacial energy with dielectric cladding materials. To tackle this problem, noble metal based alloys are proposed to replace pure noble metals because these alloys can become semi-solid with a much higher viscosity within specific temperature windows, possible allowing the thermal drawing of long continuous micro/nano metal wires. It is expected that the optical properties of the alloys would be not as satisfying as pure noble metals. However, since currently there are no other promising way to realize the novel type of metamaterial from theoretical designs, the alloy thermal drawing approach would be groundbreaking to overcome the long-standing fabrication limit.In this study, first a material selection criteria is established. The dielectric material needs to be transparent, and has low extinction coefficient and suitable refractive index. Metal has to have a large enough localized surface plasmon at the interested wavelength range. Not only opt

The objective of this study is to design and optimize metamaterial, especially those functioning in the near-IR and visible light range, with alloy wire array in a dielectric material to be fabricated by thermal drawing, overcoming the long time challenge in scalable fabrication of optical metamaterials. The feature size, wire diameter, of the metamaterial made of the wire-array structure, is demanded to be less than one-fifth of the incident light wavelength. Therefore, metal wire arrays with a wire diameter and a pitch size both less than 500 nm are required. This type of metamaterial, due to its three dimensional nature, is very hard to fabricate using conventional nanofabrication technologies. Thermal drawing technology is widely considered to be the most suitable method for fabricating this type of particular structures. Yet long, continuous metal wires with a diameter less than 500 nm have not been achieved by thermal drawing, due to an unavoidable instability in molten metal, a fluid with low viscosity and a high interfacial energy with dielectric cladding materials. To tackle this problem, noble metal based alloys are proposed to replace pure noble metals because these alloys can become semi-solid with a much higher viscosity within specific temperature windows, possible allowing the thermal drawing of long continuous micro/nano metal wires. It is expected that the optical properties of the alloys would be not as satisfying as pure noble metals. However, since currently there are no other promising way to realize the novel type of metamaterial from theoretical designs, the alloy thermal drawing approach would be groundbreaking to overcome the long-standing fabrication limit.In this study, first a material selection criteria is established. The dielectric material needs to be transparent, and has low extinction coefficient and suitable refractive index. Metal has to have a large enough localized surface plasmon at the interested wavelength range. Not only opt

The overall electrocatalytic activity toward hydrogen evolution reaction for layered transition metal dichalcogenides is governed by their intrinsic activity, the corresponding density of active sites, and the electron transfer resistance. Here, nanoengineering strategies to scale down both the lateral size and thickness of layered 1T-TiS2 powder to quantum dots (QDs) by bath sonication and probing sonication incision are employed. Uniform lateral size of 3-6 nm in the resulting QDs enhances the density of edge sites while the atomic layer thickness (1-2 nm) facilitates the electron transfer from the substrate to the edge sites. The obtained TiS2 QDs exhibit superior hydrogen evolution reaction activity over TiS2 nanosheets and MoS2 QDs prepared by the same method. The turnover frequency of TiS2 QDs with a small loading of 0.7 ng cm(-2) in an optimal deposition on electrode reached approximate to 2.0 s(-1) at an overpotential of -0.2 V versus RHE, several orders of magnitude higher than TiS2 nanosheets (0.01 s(-1)) and MoS2 QDs (0.07 s(-1)).

There is a longstanding challenge to disperse metal nanoparticles uniformly in bulk polymers for widespread applications. Conventional scale-down techniques often are only able to shrink larger elements (such as microparticles and microfibers) into micro/nano-elements (i.e. nanoparticles and nanofibers) without much altering their relative spatial and size distributions. Here we show an unusual phenomenon that tin (Sn) microparticles with both poor size distribution and spatial dispersion were stretched into uniformly dispersed and sized Sn nanoparticles in polyethersulfone (PES) through a stack and draw technique in thermal drawing. It is believed that the capillary instability plays a crucial role during thermal drawing. This novel, inexpensive, and scalable method overcomes the longstanding challenge to produce bulk polymer-metal nanocomposites (PMNCs) with a uniform dispersion of metallic nano-elements.

There is a longstanding challenge to disperse metal nanoparticles uniformly in bulk polymers for widespread applications. Conventional scale-down techniques often are only able to shrink larger elements (such as microparticles and microfibers) into micro/nano-elements (i.e. nanoparticles and nanofibers) without much altering their relative spatial and size distributions. Here we show an unusual phenomenon that tin (Sn) microparticles with both poor size distribution and spatial dispersion were stretched into uniformly dispersed and sized Sn nanoparticles in polyethersulfone (PES) through a stack and draw technique in thermal drawing. It is believed that the capillary instability plays a crucial role during thermal drawing. This novel, inexpensive, and scalable method overcomes the longstanding challenge to produce bulk polymer-metal nanocomposites (PMNCs) with a uniform dispersion of metallic nano-elements.