Getting routers out of the core: Building an optical wide area network with "multipaths"

We propose an all-optical networking solution for a wide area network (WAN) based on the notion of multipoint-to-multipoint lightpaths that, for short, we call "multipaths". A multipath concentrates the traffic of a group of source nodes on a wavelength channel using an adapted MAC protocol and multicasts this traffic to a group of destination nodes that extract their own data from the confluent stream. The proposed network can be built using existing components and appears less complex and more efficient in terms of energy consumption than alternatives like OPS and OBS. The paper presents the multipath architecture and compares its energy consumption to that of a classical router-based ISP network. A flow-aware dynamic bandwidth allocation algorithm is proposed and shown to have excellent performance in terms of throughput and delay

Solcore: A multi-scale, python-based library for modelling solar cells and semiconductor materials

Computational models can provide significant insight into the operation mechanisms and deficiencies of photovoltaic solar cells. Solcore is a modular set of computational tools, written in Python 3, for the design and simulation of photovoltaic solar cells. Calculations can be performed on ideal, thermodynamic limiting behaviour, through to fitting experimentally accessible parameters such as dark and light IV curves and luminescence. Uniquely, it combines a complete semiconductor solver capable of modelling the optical and electrical properties of a wide range of solar cells, from quantum well devices to multi-junction solar cells. The model is a multi-scale simulation accounting for nanoscale phenomena such as the quantum confinement effects of semiconductor nanostructures, to micron level propagation of light through to the overall performance of solar arrays, including the modelling of the spectral irradiance based on atmospheric conditions. In this article we summarize the capabilities in addition to providing the physical insight and mathematical formulation behind the software with the purpose of serving as both a research and teaching tool.Comment: 25 pages, 18 figures, Journal of Computational Electronics (2018

The Frontier of Tungsten Oxide Nanostructures in Electronic Applications

Electrochromic (EC) glazing has garnered significant attention recently as a crucial solution for enhancing energy efficiency in future construction and automotive sectors. EC glazing could significantly reduce the energy usage of buildings compared to traditional blinds and glazing. Despite their commercial availability, several challenges remain, including issues with switching time, leakage of electrolytes, production costs, etc. Consequently, these areas demand more attention and further studies. Among inorganic-based EC materials, tungsten oxide nanostructures are essential due to its outstanding advantages such as low voltage demand, high coloration coefficient, large optical modulation range, and stability. This review will summarize the principal design and mechanism of EC device fabrication. It will highlight the current gaps in understanding the mechanism of EC theory, discuss the progress in material development for EC glazing, including various solutions for improving EC materials, and finally, introduce the latest advancements in photo-EC devices that integrate photovoltaic and EC technologies

First experimental demonstration of real-time orchestration in a Multi-head metro network

International audienceWe present for the first time the experimental demonstration of a Real-Time control-plane on the Multi-hEad sub-wavElength swiTching (MEET), Metro architecture. The key control assets are calculated and provided to the edge nodes in a form of grant files. These grant files eliminate the contention possibility at source nodes and destinations, thus they offer a lossless passive optical grooming and multiplexing/demultiplexing at the intermediate nodes. The experimental results validate the control plane structure designed based on a deterministic operating system well scalable for a regional metro network

Imagine: Façades

Façade technology of the 20th century is related to the dissolution of the massive wall into a separation of structure and façade. Looking at the development of façade technology, after 60 years of curtain wall systems, 30 years of element-façade systems and ten years of experience with the integration of environmental services in double façades, it can be concluded that the peak of optimisation has been reached. No further technical developments can be expected by continuing to apply extra layers for each additional technical function. Understanding façades - or better envelopes - as part of an integral building, we have to see that creating the future envelope has to be done on a ’network’ basis: employing systems - but also methods of thinking - which provide the possibility to develop different aspects simultaneously and combine them as required. The envelope has to be seen as a functional part of the entire building, serving a part of the demand by providing the necessary technologies and qualities. In this regard, we have to withdraw from material and structure-orientated thinking and construction – we have to develop the envelope as a hybrid system: materials, technologies and production processes have to be integrated into the summation and combined into an all-encompassing result. Façades comprise various themes covering strategic, material and technological developments. Aspects such as function integration, networking of elements, new structures and materials as well as the addition of functions to existing structures will be investigated and explained in 85 or so concrete ideas.&nbsp

Imagine: Façades

Façade technology of the 20th century is related to the dissolution of the massive wall into a separation of structure and façade. Looking at the development of façade technology, after 60 years of curtain wall systems, 30 years of element-façade systems and ten years of experience with the integration of environmental services in double façades, it can be concluded that the peak of optimisation has been reached. No further technical developments can be expected by continuing to apply extra layers for each additional technical function. Understanding façades - or better envelopes - as part of an integral building, we have to see that creating the future envelope has to be done on a ’network’ basis: employing systems - but also methods of thinking - which provide the possibility to develop different aspects simultaneously and combine them as required. The envelope has to be seen as a functional part of the entire building, serving a part of the demand by providing the necessary technologies and qualities. In this regard, we have to withdraw from material and structure-orientated thinking and construction – we have to develop the envelope as a hybrid system: materials, technologies and production processes have to be integrated into the summation and combined into an all-encompassing result. Façades comprise various themes covering strategic, material and technological developments. Aspects such as function integration, networking of elements, new structures and materials as well as the addition of functions to existing structures will be investigated and explained in 85 or so concrete ideas.&nbsp

Metal Oxide Nanomaterials

This is a timely collection of recent diverse work on metal oxide nanomaterials, connecting their fundamental aspects and application perspectives in a concise fashion to give a broad view of the current status of this fascinating field. This book presents eight original research articles and two comprehensive reviews to highlight the recent development and understanding of different types of metal oxide nanoparticles and their use for applications in luminescence, photocatalysis, water–oil separation, optoelectronics, gas sensors, energy-saving smart windows, etc. It presents just the tip of the iceberg of the broad, dynamic, and active fundamental research and applications in the developing field of metal oxide nanomaterials by collecting a few examples of the latest advancements

Factors shaping the evolution of electronic documentation systems

The main goal is to prepare the space station technical and managerial structure for likely changes in the creation, capture, transfer, and utilization of knowledge. By anticipating advances, the design of Space Station Project (SSP) information systems can be tailored to facilitate a progression of increasingly sophisticated strategies as the space station evolves. Future generations of advanced information systems will use increases in power to deliver environmentally meaningful, contextually targeted, interconnected data (knowledge). The concept of a Knowledge Base Management System is emerging when the problem is focused on how information systems can perform such a conversion of raw data. Such a system would include traditional management functions for large space databases. Added artificial intelligence features might encompass co-existing knowledge representation schemes; effective control structures for deductive, plausible, and inductive reasoning; means for knowledge acquisition, refinement, and validation; explanation facilities; and dynamic human intervention. The major areas covered include: alternative knowledge representation approaches; advanced user interface capabilities; computer-supported cooperative work; the evolution of information system hardware; standardization, compatibility, and connectivity; and organizational impacts of information intensive environments