An empirical study of 3-vertex connectivity algorithms

Graph connectivity is one of the most basic properties of graph. Owing to this reason, it is fundamental to the studies of many important applications such as network reliability, cluster analysis, graph optimization, quantum physics, bioinformatics and social networks. Triconnectivity is a topic in graph connectivity which has been used in graph drawing, graph decomposition in geometry constraint solver, and social network studies. Hopcroft and Tarjan (1973) proposed the first linear-time algorithm for this problem. Although elegant, this algorithm is very complex and contains many minor but crucial errors which make it very difficult to understand and implement correctly. Gutwenger and Mutzel (2001) published a list of errors, outlining how to fix them and implemented the corrected algorithm.Recently, Tsin (2012) proposed a new linear-time algorithm which is based on a new graph transformation technique. Tsin\u27s algorithm is conceptually very simple and performs one less pass over the given graph than Hopcroft et al. These make the algorithm much easier to implement. In this thesis , we implemented Tsin\u27s algorithm and compare its performance with Gutwenger and Mutzel\u27s implementation of the algorithm of Hopcroft and Tarjan by carrying out an empirical study

Probing terahertz surface plasmon waves in graphene structures

Epitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale. The THz near-field images show variation of graphene properties on a scale smaller than the wavelength, and excitation of THz surface waves occurring at graphene edges, similar to that observed at metallic edges. The Fresnel reflection at the substrate SiC/air interface is also found to be altered by the presence of graphene ribbon arrays, leading to either reduced or enhanced transmission of the THz wave depending on the wave polarization and the ribbon width.Comment: accepted for publication in Applied Physics Lette

A Review on the Lifecycle Strategies Enhancing Remanufacturing

Remanufacturing is a domain that has increasingly been exploited during recent years due to its numerous advantages and the increasing need for society to promote a circular economy leading to sustainability. Remanufacturing is one of the main end-of-life (EoL) options that can lead to a circular economy. There is therefore a strong need to prioritize this option over other available options at the end-of-life stage of a product because it is the only recovery option that maintains the same quality as that of a new product. This review focuses on the different lifecycle strategies that can help improve remanufacturing; in other words, the various strategies prior to, during or after the end-of-life of a product that can increase the chances of that product being remanufactured rather than being recycled or disposed of after its end-of-use. The emergence of the fourth industrial revolution, also known as industry 4.0 (I4.0), will help enhance data acquisition and sharing between different stages in the supply chain, as well boost smart remanufacturing techniques. This review examines how strategies like design for remanufacturing (DfRem), remaining useful life (RUL), product service system (PSS), closed-loop supply chain (CLSC), smart remanufacturing, EoL product collection and reverse logistics (RL) can enhance remanufacturing. We should bear in mind that not all products can be remanufactured, so other options are also considered. This review mainly focuses on products that can be remanufactured. For this review, we used 181 research papers from three databases; Science Direct, Web of Science and Scopus