Optical memory for computing and information processing

The high data transfer rate achievable in page-oriented optical memories demands for parallel interfaces to logic circuits able to process efficiently the data. The Optically Programmable Gate Array, an enhanced version of a conventional FPGA, utilizes a holographic memory accessed by an array of VCSELs to program its logic. Combining spatial and shift multiplexing to store the configuration pages in the memory, the OPGA module is very compact and has extremely short configuration time allowing for dynamic reconfiguration. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and digit classification

Phase-change devices for simultaneous optical-electrical applications

This is the final version of the article. Available from the publisher via the DOI in this record.We present a viable pathway to the design and characterization of phase-change devices operating in a mixed-mode optical-electrical, or optoelectronic, manner. Such devices have potential applications ranging from novel displays to optically-gated switches to reconfigurable metamaterials-based devices. With this in mind, a purpose-built optoelectronics probe station capable of simultaneous optical-electrical excitation and simultaneous optical-electrical response measurement has been designed and constructed. Two prototype phase-change devices that might exploit simultaneous optical and electrical effects and/or require simultaneous optical and electrical characterisation, namely a mixed-mode cross-bar type structure and a microheater-based structure, have been designed, fabricated and characterized. The microheater-based approach was shown to be capable of successful thermally-induced cycling, between amorphous and crystalline states, of large-area phase-change devices, making it attractive for practicable pixel fabrication in phase-change display applications.The authors would like to acknowledge funding via the EPSRC ChAMP and WAFT grants (EP/M015130/1 and EP/M015173/1). Y-YA and CDW would also like to acknowledge funding via US Naval Research Laboratories ONRG programme (#N62909-16-1-2174

Telecommunication Systems

This book is based on both industrial and academic research efforts in which a number of recent advancements and rare insights into telecommunication systems are well presented. The volume is organized into four parts: "Telecommunication Protocol, Optimization, and Security Frameworks", "Next-Generation Optical Access Technologies", "Convergence of Wireless-Optical Networks" and "Advanced Relay and Antenna Systems for Smart Networks." Chapters within these parts are self-contained and cross-referenced to facilitate further study

Technology 2000, volume 1

The purpose of the conference was to increase awareness of existing NASA developed technologies that are available for immediate use in the development of new products and processes, and to lay the groundwork for the effective utilization of emerging technologies. There were sessions on the following: Computer technology and software engineering; Human factors engineering and life sciences; Information and data management; Material sciences; Manufacturing and fabrication technology; Power, energy, and control systems; Robotics; Sensors and measurement technology; Artificial intelligence; Environmental technology; Optics and communications; and Superconductivity

Development of Innovative Microfluidic Polymeric Technologies for Point-of-care & Integrated Diagnostics Devices

This thesis presents the development of four different microfluidic technologies that can be used as stand-alone devices or integrated in point-of-care systems. The first technology is a rapid, low-cost, portable microfluidic system for assessing the somatic cell count and fat content of milk in 15 min using a “sample-in, answer-out” approach. The system consists of twelve independent microfluidic devices, essentially flattened funnel structures, fabricated on the footprint of a plastic compact disc (CD). The assay separates cells and fat globules based on their densities (by differential sedimentation), concentrating white cells in the closed-end channel near the outer rim of the CD for estimation of total “cell pellet” volume, while fat globules move toward the center of disc rotation, forming a fat “band” in the funnel. The closed-end channel provides accurate cell counts over the range 50,000 to over 3,000,000 cells per mL. A technique is also presented to recirculate liquids in a microfluidic channel by alternating the predominance of centrifugal and capillary forces. With this technique, liquid volumes of μL to mL can be sampled with many sizes of microfluidic channels that contain only a fraction of the sample at one time, provided the channel wall with greatest surface area is hydrophilic. We present a theoretical model describing the balance of centrifugal and capillary forces in the device and validate the model experimentally. Towards the development of an integrated pathogen identification system, two other technologies are demonstrated and implemented. The design, fabrication, and characterization of a polymer centrifugal microfluidic system for the specific detection of bacterial pathogens is presented. This single-cartridge platform integrates bacteria capture and concentration, supernatant solution removal, lysis, and nucleic-acid sequence-based amplification (NASBA) in a single unit. The unit is fabricated using multilayer lamination and consists of five different polymer layers. Bacteria capture and concentration are accomplished by sedimentation in five minutes. Centrifugation forces also drive the subsequent steps. A wax valve is integrated in the cartridge to enable high-speed centrifugation. Oil is used to prevent evaporation during reactions requiring thermal cycling. Device functionality was demonstrated by real-time detection of E. coli cells from a 200-μL sample. Finally, the laser-printer-based fabrication of pressure-resistant microfluidic single-use valves is reported, along with their implementation on pressure-driven and centrifugal microfluidic platforms. A laser printer is used to selectively deposit toner on a plastic substrate in the form of circular dots. After assembly into a microfluidic device, the valve is opened (melted) with a pulse of laser light. This is an easy approach to connect multiple fluidic levels. This simple technology is compatible with a range of polymer microfabrication technologies and should facilitate the development of fully integrated, (re)configurable, and automated lab-on-a-chip systems, particularly when reagents must be stored on chip for extended periods, e.g. for medical diagnostic devices, lab-on-a-chip synthetic systems, or hazardous bio/chemical analysis platforms

Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems

We present the science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems, targeting an evolution in technology, that might lead to impacts and benefits reaching into most areas of society. This roadmap was developed within the framework of the European Graphene Flagship and outlines the main targets and research areas as best understood at the start of this ambitious project. We provide an overview of the key aspects of graphene and related materials (GRMs), ranging from fundamental research challenges to a variety of applications in a large number of sectors, highlighting the steps necessary to take GRMs from a state of raw potential to a point where they might revolutionize multiple industries. We also define an extensive list of acronyms in an effort to standardize the nomenclature in this emerging field.Peer ReviewedPostprint (published version

International VLBI Service for Geodesy and Astrometry 2011 Annual Report

This volume of reports is the 2011 Annual Report of the International VLBI Service for Geodesy and Astrometry (IVS). The individual reports were contributed by VLBI groups in the international geodetic and astrometric community who constitute the components of IVS. The 2011 Annual Report documents the work of these IVS components over the period January 1, 2011 through December 31, 2011. The reports document changes, activities, and progress of the IVS. The entire contents of this Annual Report also appear on the IVS Web site at http://ivscc.gsfc.nasa.gov/publications/ar2011