Physical Foundations of Landauer's Principle

We review the physical foundations of Landauer's Principle, which relates the loss of information from a computational process to an increase in thermodynamic entropy. Despite the long history of the Principle, its fundamental rationale and proper interpretation remain frequently misunderstood. Contrary to some misinterpretations of the Principle, the mere transfer of entropy between computational and non-computational subsystems can occur in a thermodynamically reversible way without increasing total entropy. However, Landauer's Principle is not about general entropy transfers; rather, it more specifically concerns the ejection of (all or part of) some correlated information from a controlled, digital form (e.g., a computed bit) to an uncontrolled, non-computational form, i.e., as part of a thermal environment. Any uncontrolled thermal system will, by definition, continually re-randomize the physical information in its thermal state, from our perspective as observers who cannot predict the exact dynamical evolution of the microstates of such environments. Thus, any correlations involving information that is ejected into and subsequently thermalized by the environment will be lost from our perspective, resulting directly in an irreversible increase in total entropy. Avoiding the ejection and thermalization of correlated computational information motivates the reversible computing paradigm, although the requirements for computations to be thermodynamically reversible are less restrictive than frequently described, particularly in the case of stochastic computational operations. There are interesting possibilities for the design of computational processes that utilize stochastic, many-to-one computational operations while nevertheless avoiding net entropy increase that remain to be fully explored.Comment: 42 pages, 15 figures, extended postprint of a paper published in the 10th Conf. on Reversible Computation (RC18), Leicester, UK, Sep. 201

Power Electronics and Energy Management for Battery Storage Systems

The deployment of distributed renewable generation and e-mobility systems is creating a demand for improved dynamic performance, flexibility, and resilience in electrical grids. Various energy storages, such as stationary and electric vehicle batteries, together with power electronic interfaces, will play a key role in addressing these requests thanks to their enhanced functionality, fast response times, and configuration flexibility. For the large-scale implementation of this technology, the associated enabling developments are becoming of paramount importance. These include energy management algorithms; optimal sizing and coordinated control strategies of different storage technologies, including e-mobility storage; power electronic converters for interfacing renewables and battery systems, which allow for advanced interactions with the grid; and increase in round-trip efficiencies by means of advanced materials, components, and algorithms. This Special Issue contains the developments that have been published b researchers in the areas of power electronics, energy management and battery storage. A range of potential solutions to the existing barriers is presented, aiming to make the most out of these emerging technologies

Low-power Wearable Healthcare Sensors

Advances in technology have produced a range of on-body sensors and smartwatches that can be used to monitor a wearer’s health with the objective to keep the user healthy. However, the real potential of such devices not only lies in monitoring but also in interactive communication with expert-system-based cloud services to offer personalized and real-time healthcare advice that will enable the user to manage their health and, over time, to reduce expensive hospital admissions. To meet this goal, the research challenges for the next generation of wearable healthcare devices include the need to offer a wide range of sensing, computing, communication, and human–computer interaction methods, all within a tiny device with limited resources and electrical power. This Special Issue presents a collection of six papers on a wide range of research developments that highlight the specific challenges in creating the next generation of low-power wearable healthcare sensors

Surface composites and functionalisation : enhancement of aluminium alloy 7075-T651 via friction stir processing

Abstract: This research work is aimed at modifying and enhancing the properties of aluminium alloy 7075- T651 through the friction stir processing (FSP) technique, in order to improve the mechanical, electrochemical, structural, tribological as well as the metallurgical properties which include micro- and macro- structural analysis through XRD and Image processing of grain size and grain flow patterns determination, by reinforcing the parent metal. The surface modification of the parent metal has been made possible in the past via different techniques,such as laser surfacing, electronbeam welding and thermal spraying; but in recent years, the friction stir processing (FSP) technology has been adopted to cater for the complex methods of surface enhancement. FSP is well-renowned for its short route of fabrication, densification, grain refinement, homogenization of the precipitates of composite substances, nugget zone homogeneity. These have led to the efficient surface enhancement, significant and remarkable improvement in hardness, ductility, strength, increased fatigue life, as well as formability within which the bulk properties are still intact. The use of FSP in the fabrication of metal matrix composites (MMCs), especially aluminium matrix composites (AMCs) and aluminium hybrid composites (AHCs) were dealt with in this study...Ph.D. (Mechanical Engineering

The 9th International Conference on Sustainable Development

The International Conference on Sustainable Development (ICSD) was held virtually on September 20-21, 2021, with the conference theme “Research for Impact: A Sustainable and Inclusive Planet.” ICSD provides a forum for academia, government, civil society, UN agencies, and the private sector to come together to share practical solutions to achieve Sustainable Development Goals (SDGs). The two-day conference hosted 49 different sessions across multiple time zones to accommodate the global audience, with 204 oral presenters, 239 poster presenters, and 977 total authors