Exploring the topology of a region object requires the mathematical study of its geometric properties that are preserved under deformations. A moving region whose location and extent change over time can undergo several topological changes such as the splitting of a region or the formation of a hole. The study of this kind of changes is important in many applications, e.g., for the topology con...

Topological states of light represent counterintuitive optical modes localized at boundaries finite-size structures that originate from the properties bulk. Being defined by bulk properties, such boundary are insensitive to certain types perturbations, thus naturally enhancing robustness photonic circuitries. Conventionally, N-dimensional correspond (N-1)-dimensional states. The higher-order bu...

Topology control protocols have been proposed to construct efficient network topologies with several design goals, e.g., network-wide connectivity, minimal energy cost, symmetry, lower nodal degree, and therefore higher spatial reuse or lower interferences. Neighbor-based topology control protocols are simple and assume that each node in the network is connected to its k least-distant neighbors...

The topology control is one of the research focuses in wireless sensor networks. Different network topologies will have different effects on the properties of the network, such as the reliability, energy consumption and latency. In order to study the relationship between the topology and the network performance, in this paper we have designed three kinds of topology models which are regular hex...

Due to the inefficiency of a flat topology, most wireless sensor networks (WSNs) have a cluster or tree structure; but this causes an imbalance of residual energy between nodes, which gets worse over time as nodes become defunct and replacements are inserted. Multiple layers are better then the typical two-layer cluster-based topology, because it can better accommodate nodes with different leve...

In this paper, we study the problem of how to design overlay topologies in multi-hop wireless networks such that the overlays achieve perfect resilience, in terms of all cooperative nodes included but misbehaving nodes excluded, and preserve the k-connectivity with high probability. To address this problem, we propose a new distributed topology control protocol called PROACtive. By using PROACt...

Nanotechnology involves the ability to see and control individual atoms and molecules which are about 100 nanometer or smaller. One of the major tools used in this field is atomic force microscopy which uses a wealth of techniques to measure the topography and investigates the surface forces in nanoscale. Friction force is the representation of the surface interaction between two surfaces an...