Advanced training of specialists in area of fiber-optic communication lines maintenance
NASA Astrophysics Data System (ADS)
Andreev, Vladimir A.; Voronkov, Andrey A.; Bukashkin, Sergey A.; Buzova, Maria A.
2017-04-01
The paper considers the concept of fiber-optic communication lines (FOCL) maintenance. Performance criterion of FOCL technical maintenance was proposed. For the first time the algorithm for evaluation of the FOCL maintenance efficiency at telecommunication specialists training was applied.
77 FR 43592 - Public Utility District No. 1 of Snohomish County, WA; Notice of Technical Meeting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-25
... issues raised by PC Landing and the Federal Communications Commission regarding the proximity of the proposed Admiralty Inlet Tidal Project to PC Landing's fiber optic communication cable, and discuss the...
Modeling and Performance Analysis of 10 Gbps Inter-satellite Optical Wireless Communication Link
NASA Astrophysics Data System (ADS)
Singh, Mehtab
2017-12-01
Free-space optical (FSO) communication has the advantages of two of the most predominant data transmission technologies - optical fiber communication and wireless communication. Most of the technical aspects of FSO are similar to that of optical fiber communication, with major difference in the information signal propagation medium which is free space in case of FSO rather than silica glass in optical fiber communication. One of the most important applications of FSO is inter-satellite optical wireless communication (IsOWC) links which will be deployed in the future in space. The IsOWC links have many advantages over the previously existing microwave satellite communication technologies such as higher bandwidth, lower power consumption, low cost of implementation, light size, and weight. In this paper, modeling and performance analysis of a 10-Gbps inter-satellite communication link with two satellites separated at a distance of 1,200 km has been done using OPTISYSTEM simulation software. Performance has been analyzed on the basis of quality factor, signal to noise ratio (SNR), and total power of the received signal.
Spatial Soliton Interactions for Photonic Switching. Part I
2000-03-07
technique , a fully vectorial, first-order nonlinear wave equation that consistently includes terms two -orders beyond the slowly-varying amplitude , slowly...by using two tunable mode-locked Er-doped fiber lasers ," in Conference on Optical Fiber Communications, OSA Technical Digest Series, vol. 4, 1994...instead, based on optical logic gates. In addition, optical logic could be used for contention resolution, real-time encryption /decryption, and other
Core-to-core uniformity improvement in multi-core fiber Bragg gratings
NASA Astrophysics Data System (ADS)
Lindley, Emma; Min, Seong-Sik; Leon-Saval, Sergio; Cvetojevic, Nick; Jovanovic, Nemanja; Bland-Hawthorn, Joss; Lawrence, Jon; Gris-Sanchez, Itandehui; Birks, Tim; Haynes, Roger; Haynes, Dionne
2014-07-01
Multi-core fiber Bragg gratings (MCFBGs) will be a valuable tool not only in communications but also various astronomical, sensing and industry applications. In this paper we address some of the technical challenges of fabricating effective multi-core gratings by simulating improvements to the writing method. These methods allow a system designed for inscribing single-core fibers to cope with MCFBG fabrication with only minor, passive changes to the writing process. Using a capillary tube that was polished on one side, the field entering the fiber was flattened which improved the coverage and uniformity of all cores.
A system for respiratory motion detection using optical fibers embedded into textiles.
D'Angelo, L T; Weber, S; Honda, Y; Thiel, T; Narbonneau, F; Luth, T C
2008-01-01
In this contribution, a first prototype for mobile respiratory motion detection using optical fibers embedded into textiles is presented. The developed system consists of a T-shirt with an integrated fiber sensor and a portable monitoring unit with a wireless communication link enabling the data analysis and visualization on a PC. A great effort is done worldwide to develop mobile solutions for health monitoring of vital signs for patients needing continuous medical care. Wearable, comfortable and smart textiles incorporating sensors are good approaches to solve this problem. In most of the cases, electrical sensors are integrated, showing significant limits such as for the monitoring of anaesthetized patients during Magnetic Resonance Imaging (MRI). OFSETH (Optical Fibre Embedded into technical Textile for Healthcare) uses optical sensor technologies to extend the current capabilities of medical technical textiles.
NASA Astrophysics Data System (ADS)
Parekh, Devang; Nguyen, Nguyen X.
2018-02-01
The recent advent of Ultra-high-definition television (also known as Ultra HD television, Ultra HD, UHDTV, UHD and Super Hi-Vision) has accelerated a demand for a Fiber-in-the-Premises video communication (VCOM) solution that converges toward 100Gbps and Beyond. Hybrid Active-Optical-Cables (AOC) is a holistic connectivity platform well suited for this "The Last Yard" connectivity; as it combines both copper and fiber optics to deliver a high data-rate and power transmission needed. While technically feasible yet challenging to manufacture, hybrid-AOC could be a holygrail fiber-optics solution that dwarfs the volume of both telecom and datacom connection in the foreseeable future.
Fiber optical parametric amplifiers in optical communication systems
Marhic (†), Michel E; Andrekson, Peter A; Petropoulos, Periklis; Radic, Stojan; Peucheret, Christophe; Jazayerifar, Mahmoud
2015-01-01
The prospects for using fiber optical parametric amplifiers (OPAs) in optical communication systems are reviewed. Phase-insensitive amplifiers (PIAs) and phase-sensitive amplifiers (PSAs) are considered. Low-penalty amplification at/or near 1 Tb/s has been achieved, for both wavelength- and time-division multiplexed formats. High-quality mid-span spectral inversion has been demonstrated at 0.64 Tb/s, avoiding electronic dispersion compensation. All-optical amplitude regeneration of amplitude-modulated signals has been performed, while PSAs have been used to demonstrate phase regeneration of phase-modulated signals. A PSA with 1.1-dB noise figure has been demonstrated, and preliminary wavelength-division multiplexing experiments have been performed with PSAs. 512 Gb/s have been transmitted over 6,000 km by periodic phase conjugation. Simulations indicate that PIAs could reach data rate x reach products in excess of 14,000 Tb/s × km in realistic wavelength-division multiplexed long-haul networks. Technical challenges remaining to be addressed in order for fiber OPAs to become useful for long-haul communication networks are discussed. PMID:25866588
NASA Astrophysics Data System (ADS)
Hanson, A. G.
1987-03-01
The learning experience of a group of Federal-agency planners who face upgrading or augmenting existing on-premises communication systems and building wiring is documented. In July 1984, an interagency Fiber Optics Task Group was formed under the aegis of the Federal Telecommunication Standards Committee to study on-premises distribution systems, with emphasis on optical fiber implementation, sharing mutual problems and potential solutions for them. Chronological summary records of technical content of 11 Task Group meetings through September 1986 are summarized. Also condensed are the engineering presentations to the Task Group by industry on applicable state-of-the-art technology, including local area networks, private automatic branch exchanges, building wiring architecture, and optic fiber systems and components.
Onboard connectivity network for command-and-control aircraft
NASA Astrophysics Data System (ADS)
Artz, Timothy J.
1993-02-01
Command and control (C2) aircraft are host to an array of communications, information processing, and electronic control systems. The previous method of interconnecting this equipment involves point-to-point wiring harnesses between devices. A fiber optic broadband bus can be used to improve this situation by consolidating equipment connections on a shared medium. This network, known as the Onboard Connectivity Network (OCN), is being prototypes for application on the U.S. Government's Special Air Mission aircraft. Significant weight reduction and simplified future systems integration are the primary benefits of the OCN. The OCN design integrates voice, data, control, and video communications on a 3GHZ single mode fiber backbone. Communications within the aircraft use 500 MHz coaxial cable subnetworks connected to the backbone. The entire network is a dual redundant system for enhanced reliability. Node topologies are based on VMEbus to encourage use of commercial products and facilitate future evolution of the backbone topology. Network encryption technologies are being developed for OCN communications security. Automated workstations will be implemented to control and switch communications assets and to provide a technical control, test, and monitoring function.
Integration of the White Sands Complex into a Wide Area Network
NASA Technical Reports Server (NTRS)
Boucher, Phillip Larry; Horan, Sheila, B.
1996-01-01
The NASA White Sands Complex (WSC) satellite communications facility consists of two main ground stations, an auxiliary ground station, a technical support facility, and a power plant building located on White Sands Missile Range. When constructed, terrestrial communication access to these facilities was limited to copper telephone circuits. There was no local or wide area communications network capability. This project incorporated a baseband local area network (LAN) topology at WSC and connected it to NASA's wide area network using the Program Support Communications Network-Internet (PSCN-I). A campus-style LAN is configured in conformance with the International Standards Organization (ISO) Open Systems Interconnect (ISO) model. Ethernet provides the physical and data link layers. Transmission Control Protocol and Internet Protocol (TCP/IP) are used for the network and transport layers. The session, presentation, and application layers employ commercial software packages. Copper-based Ethernet collision domains are constructed in each of the primary facilities and these are interconnected by routers over optical fiber links. The network and each of its collision domains are shown to meet IEEE technical configuration guidelines. The optical fiber links are analyzed for the optical power budget and bandwidth allocation and are found to provide sufficient margin for this application. Personal computers and work stations attached to the LAN communicate with and apply a wide variety of local and remote administrative software tools. The Internet connection provides wide area network (WAN) electronic access to other NASA centers and the world wide web (WWW). The WSC network reduces and simplifies the administrative workload while providing enhanced and advanced inter-communications capabilities among White Sands Complex departments and with other NASA centers.
NASA Astrophysics Data System (ADS)
The present conference on the development status of communications systems in the context of electronic warfare gives attention to topics in spread spectrum code acquisition, digital speech technology, fiber-optics communications, free space optical communications, the networking of HF systems, and applications and evaluation methods for digital speech. Also treated are issues in local area network system design, coding techniques and applications, technology applications for HF systems, receiver technologies, software development status, channel simultion/prediction methods, C3 networking spread spectrum networks, the improvement of communication efficiency and reliability through technical control methods, mobile radio systems, and adaptive antenna arrays. Finally, communications system cost analyses, spread spectrum performance, voice and image coding, switched networks, and microwave GaAs ICs, are considered.
Education kits for fiber optics, optoelectronics, and optical communications
NASA Astrophysics Data System (ADS)
Hájek, Martin; Švrček, Miroslav
2007-04-01
Our company MIKROKOM, s.r.o. is engaged for many years in development of education equipment and kits for fiber optics, optoelectronics and optical communications. We would like to inform competitors of conference about results of this long-time development. Requirements on education kits and equipment in a modern and dynamic area as is optical communications and fiber optics are quite difficult. The education kits should to clearly introduce students to given issue - the most important physical principles and technical approaches, but it should to introduce also to new and modern technologies, which are quickly changing and developing. On the other hand should be these tools and kits reasonable for the schools. In our paper we would like to describe possible ways of development of this education kits and equipment and present our results of long-time work, which covers very wide range. On the one hand we developed equipment and kits for clear demonstration of physical effects using plastic optical fibers POF, next we prepare kits with a glass fibers, which are the most used fibers in practice and after as much as the kits, which covers broad range of passive and active elements of the optical networks and systems and which makes possible to create complex optical transmission connection. This kind of systems with using corresponding tools and equipment introduce the students to properties, manipulation, measurement and usage of optical fibers, traces and many active and passive components. Furthermore, with using different sorts of optical sources, photodetectors, fiber optics couplers etc., students can get acquainted with all optoelectronics transmission system, which uses different sorts of signals. Special part will be devoted also to effort mentioned before - to implement modern technologies such as e.g. Wavelength Division Multiplex (WDM) into the education kits. Our presentation will inform auditors about development of mentioned education kits and equipment and about their potentials and practical utility at school education.
NASA Astrophysics Data System (ADS)
Oguchi, Kimio
2016-03-01
The recent dramatic advances in information and communication technologies have yielded new environments. However, adoption still differs area by area. To realize the future broadband environment that everyone can enjoy everywhere, several technical issues have to be resolved before network penetration becomes ubiquitous. One such key is the use of fiber optics for the home and mobile services. This article overviews initial observations drawn from numerical survey data gathered over the last decade in several countries/regions, and gives some example scenarios for network/service evolution. One result implies that implementing new/future services must consider the gross domestic product impact.
Natural cellulose fibers from soybean straw.
Reddy, Narendra; Yang, Yiqi
2009-07-01
This paper reports the development of natural cellulose technical fibers from soybean straw with properties similar to the natural cellulose fibers in current use. About 220 million tons of soybean straw available in the world every year could complement the byproducts of other major food crops as inexpensive, abundant and annually renewable sources for natural cellulose fibers. Using the agricultural byproducts as sources for fibers could help to address the concerns on the future price and availability of both the natural and synthetic fibers in current use and also help to add value to the food crops. A simple alkaline extraction was used to obtain technical fibers from soybean straw and the composition, structure and properties of the fibers was studied. Technical fibers obtained from soybean straw have high cellulose content (85%) but low% crystallinity (47%). The technical fibers have breaking tenacity (2.7 g/den) and breaking elongation (3.9%) higher than those of fibers obtained from wheat straw and sorghum stalk and leaves but lower than that of cotton. Overall, the structure and properties of the technical fibers obtained from soybean straw indicates that the fibers could be suitable for use in textile, composite and other industrial applications.
Research and Development on Ultra-Lightweight Low-Loss Optical Fiber Communication Cable.
FIBER OPTICS TRANSMISSION LINES, LIGHTWEIGHT), GLASS , FIBERS , ORGANIC COATINGS, POLYURETHANE RESINS, SOLUTIONS(GENERAL), POWDERS, ELECTROSTATICS...EXTRUSION, RUGGEDIZED EQUIPMENT, BROADBAND, OPTICAL COMMUNICATIONS, TACTICAL COMMUNICATIONS, FIBER OPTICS, LOSSES.
Dense wavelength division multiplexing devices for metropolitan-area datacom and telecom networks
NASA Astrophysics Data System (ADS)
DeCusatis, Casimer M.; Priest, David G.
2000-12-01
Large data processing environments in use today can require multi-gigabyte or terabyte capacity in the data communication infrastructure; these requirements are being driven by storage area networks with access to petabyte data bases, new architecture for parallel processing which require high bandwidth optical links, and rapidly growing network applications such as electronic commerce over the Internet or virtual private networks. These datacom applications require high availability, fault tolerance, security, and the capacity to recover from any single point of failure without relying on traditional SONET-based networking. These requirements, coupled with fiber exhaust in metropolitan areas, are driving the introduction of dense optical wavelength division multiplexing (DWDM) in data communication systems, particularly for large enterprise servers or mainframes. In this paper, we examine the technical requirements for emerging nextgeneration DWDM systems. Protocols for storage area networks and computer architectures such as Parallel Sysplex are presented, including their fiber bandwidth requirements. We then describe two commercially available DWDM solutions, a first generation 10 channel system and a recently announced next generation 32 channel system. Technical requirements, network management and security, fault tolerant network designs, new network topologies enabled by DWDM, and the role of time division multiplexing in the network are all discussed. Finally, we present a description of testing conducted on these networks and future directions for this technology.
NASA Astrophysics Data System (ADS)
Liu, Ling
The primary goal of this research is the analysis, development, and experimental demonstration of an adaptive phase-locked fiber array system for free-space optical communications and laser beam projection applications. To our knowledge, the developed adaptive phase-locked system composed of three fiber collimators (subapertures) with tip-tilt wavefront phase control at each subaperture represents the first reported fiber array system that implements both phase-locking control and adaptive wavefront tip-tilt control capabilities. This research has also resulted in the following innovations: (a) The first experimental demonstration of a phase-locked fiber array with tip-tilt wave-front aberration compensation at each fiber collimator; (b) Development and demonstration of the fastest currently reported stochastic parallel gradient descent (SPGD) system capable of operation at 180,000 iterations per second; (c) The first experimental demonstration of a laser communication link based on a phase-locked fiber array; (d) The first successful experimental demonstration of turbulence and jitter-induced phase distortion compensation in a phase-locked fiber array optical system; (e) The first demonstration of laser beam projection onto an extended target with a randomly rough surface using a conformal adaptive fiber array system. Fiber array optical systems, the subject of this study, can overcome some of the draw-backs of conventional monolithic large-aperture transmitter/receiver optical systems that are usually heavy, bulky, and expensive. The primary experimental challenges in the development of the adaptive phased-locked fiber-array included precise (<5 microrad) alignment of the fiber collimators and development of fast (100kHz-class) phase-locking and wavefront tip-tilt control systems. The precise alignment of the fiber collimator array is achieved through a specially developed initial coarse alignment tool based on high precision piezoelectric picomotors and a dynamic fine alignment mechanism implemented with specially designed and manufactured piezoelectric fiber positioners. Phase-locking of the fiber collimators is performed by controlling the phases of the output beams (beamlets) using integrated polarization-maintaining (PM) fiber-coupled LiNbO3 phase shifters. The developed phase-locking controllers are based on either the SPGD algorithm or the multi-dithering technique. Subaperture wavefront phase tip-tilt control is realized using piezoelectric fiber positioners that are controlled using a computer-based SPGD controller. Both coherent (phase-locked) and incoherent beam combining in the fiber array system are analyzed theoretically and experimentally. Two special fiber-based beam-combining testbeds have been built to demonstrate the technical feasibility of phase-locking compensation prior to free-space operation. In addition, the reciprocity of counter-propagating beams in a phase-locked fiber array system has been investigated. Coherent beam combining in a phase-locking system with wavefront phase tip-tilt compensation at each subaperture is successfully demonstrated when laboratory-simulated turbulence and wavefront jitters are present in the propagation path of the beamlets. In addition, coherent beam combining with a non-cooperative extended target in the control loop is successfully demonstrated.
Optical fiber sensors for materials and structures characterization
NASA Technical Reports Server (NTRS)
Lindner, D. K.; Claus, R. O.
1991-01-01
The final technical report on Optical Fiber Sensors for Materials and Structures Characterization, covering the period August 1990 through August 1991 is presented. Research programs in the following technical areas are described; sapphire optical fiber sensors; vibration analysis using two-mode elliptical core fibers and sensors; extrinsic Fabry-Perot interferometer development; and coatings for fluorescent-based sensor. Research progress in each of these areas was substantial, as evidenced by the technical publications which are included as appendices.
Research reports: 1990 NASA/ASEE Summer Faculty Fellowship Program
NASA Technical Reports Server (NTRS)
Anderson, Loren A. (Editor); Beymer, Mark A. (Editor)
1990-01-01
A collection of technical reports on research conducted by the participants in this program is presented. The topics covered include: human-computer interface software, multimode fiber optic communication links, electrochemical impedance spectroscopy, rocket-triggered lightning, robotics, a flammability study of thin polymeric film materials, a vortex shedding flowmeter, modeling of flow systems, monomethyl hydrazine vapor detection, a rocket noise filter system using digital filters, computer programs, lower body negative pressure, closed ecological systems, and others. Several reports with respect to space shuttle orbiters are presented.
2013-09-01
the fiber-optic receiver. When electrical power was restored by reinserting the plug, there could be no guarantee that all of the relays within the...useable set of coded instructions was expected to take approximately 3 man-months to develop and would incur costs, in labor , much greater than the...man-hour labor load was expected to be only about a month, the inability to quickly verify a “final” circuit design represented the highest risk
Multiple-Ring Digital Communication Network
NASA Technical Reports Server (NTRS)
Kirkham, Harold
1992-01-01
Optical-fiber digital communication network to support data-acquisition and control functions of electric-power-distribution networks. Optical-fiber links of communication network follow power-distribution routes. Since fiber crosses open power switches, communication network includes multiple interconnected loops with occasional spurs. At each intersection node is needed. Nodes of communication network include power-distribution substations and power-controlling units. In addition to serving data acquisition and control functions, each node acts as repeater, passing on messages to next node(s). Multiple-ring communication network operates on new AbNET protocol and features fiber-optic communication.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peach, D.F.
1987-12-01
Fiber optic telecommunication systems are susceptible to both natural and man-made stress. National Security/Emergency Preparedness (NSEP) is a function of how durable these systems are in light of projected levels of stress. Emergency Preparedness in 1987 is not just a matter of--can they deliver food, water, energy and other essentials--but can they deliver the vital information necessary to maintain corporate function of our country. 'Communication stamina' is a function of 'probability of survival' when faced with stress. This report provides an overview of the enhancements to a fiber-optic communication system/installation that will increase durability. These enhancements are grouped, based onmore » their value in protecting the system, such that a Multitier Specification is created that presents multiple levels of hardness. Mitigation of effects due to high-altitude electromagnetic pulse (HEMP) and gamma radiation, and protection from vandalism and weather events are discussed in the report. The report is presented in two volumes. Volume I presents the Multitier Specification in a format that is usable for management review. The attributes of specified physical parameters, and the levels of protection stated in Volume I, are discussed in more detail in Volume II.« less
Fiber Optic Communications Technology. A Status Report.
ERIC Educational Resources Information Center
Hull, Joseph A.
Fiber optic communications (communications over very pure glass transmission channels of diameter comparable to a human hair) is an emerging technology which promises most improvements in communications capacity at reasonable cost. The fiber transmission system offers many desirable characteristics representing improvements over conventional…
NASA/ASEE Summer Faculty Fellowship Program
NASA Technical Reports Server (NTRS)
Hosler, E. Ramon (Editor); Valdes, Carol (Editor); Brown, Tom (Editor)
1993-01-01
This document is a collection of technical reports on research conducted by the participants in the 1993 NASA/ASEE Summer Faculty Fellowship Program at KSC. The basic common objectives of the Program are: to further the professional knowledge of qualified engineering and science faculty members; to stimulate an exchange of ideas between participants and NASA; to enrich and refresh the research and teaching activities of participants' institutions; and to contribute to the research objectives of the NASA centers. 1993 topics include wide band fiber optic communications, a prototype expert/information system for examining environmental risks of KSC activities, alternatives to premise wiring using ATM and microcellular technologies, rack insertion end effector (RIEE) automation, FTIR quantification of industrial hydraulic fluids in perchloroethylene, switch configuration for migration to optical fiber network, and more.
Everything You Always Wanted to Know about Fiber Optics but Were Afraid to Ask...
ERIC Educational Resources Information Center
Bunch, Robert M.
1993-01-01
Explains light-wave communication and optical fibers. The impact of fiber optics on communication is discussed; uses of fiber optic technology in elementary, secondary, and higher education are described; and possible futures of light-wave communication are considered, including Integrated Services Digital Networks and the National Research and…
Fernandez-Tendero, Eva; Day, Arnaud; Legros, Sandrine; Habrant, Anouck; Hawkins, Simon
2017-01-01
Interest in hemp (Cannabis sativa L.) is increasing due to the development of a new range of industrial applications based on bast fibers. However the variability of bast fiber yield and quality represents an important barrier to further exploitation. Primary and secondary fiber content was examined in two commercial hemp varieties (Fedora 17, Santhica 27) grown under contrasted sowing density and irrigation conditions. Both growing conditions and hemp varieties impact stem tissue architecture with a large effect on the proportion of secondary fibers but not primary fibers. Attenuated total reflectance infrared spectroscopy allowed the discrimination of manually-isolated native primary fibers and secondary fibers but did not reveal any clustering according to growing conditions and variety. Infrared data were confirmed by wet chemistry analyses that revealed slight but significant differences between primary and secondary fiber cell wall composition. Infrared spectroscopy of technical fibers obtained after mechanical defibering revealed differences with native primary, but not secondary fibers and also discriminated samples obtained from plants grown under different conditions. Altogether the results suggested that the observed variability of hemp technical fibers could be partially explained by i) differences in secondary fiber production and ii) differential behavior during mechanical defibering resulting in unequal separation of primary and secondary fibers. PMID:28640922
Fernandez-Tendero, Eva; Day, Arnaud; Legros, Sandrine; Habrant, Anouck; Hawkins, Simon; Chabbert, Brigitte
2017-01-01
Interest in hemp (Cannabis sativa L.) is increasing due to the development of a new range of industrial applications based on bast fibers. However the variability of bast fiber yield and quality represents an important barrier to further exploitation. Primary and secondary fiber content was examined in two commercial hemp varieties (Fedora 17, Santhica 27) grown under contrasted sowing density and irrigation conditions. Both growing conditions and hemp varieties impact stem tissue architecture with a large effect on the proportion of secondary fibers but not primary fibers. Attenuated total reflectance infrared spectroscopy allowed the discrimination of manually-isolated native primary fibers and secondary fibers but did not reveal any clustering according to growing conditions and variety. Infrared data were confirmed by wet chemistry analyses that revealed slight but significant differences between primary and secondary fiber cell wall composition. Infrared spectroscopy of technical fibers obtained after mechanical defibering revealed differences with native primary, but not secondary fibers and also discriminated samples obtained from plants grown under different conditions. Altogether the results suggested that the observed variability of hemp technical fibers could be partially explained by i) differences in secondary fiber production and ii) differential behavior during mechanical defibering resulting in unequal separation of primary and secondary fibers.
Stability of Glass Fiber-Plastic Composites
1974-11-01
miniiiii’ 5 0712 01016774 9 x TECHNICA. . LIBRARY Jt U*Al>/l 1 Technical Report RL-75-6 STABILITY OF GLASS FIBER -PLASTIC COMPOSITES Wartan A...Subtitle) STABILITY OF GLASS FIBER -PLASTIC COMPOSITES 5. TYPE OF REPORT & PERIOD COVERED Technical Report 6. PERFORMING ORG. REPORT NUMBER 7...Exploratory research was conducted to determine the stages and nature of degradation of glass fiber -plastic composite systems under various environmental
Laser Communications and Fiber Optics Lab Manual. High-Technology Training Module.
ERIC Educational Resources Information Center
Biddick, Robert
This laboratory training manual on laser communications and fiber optics may be used in a general technology-communications course for ninth graders. Upon completion of this exercise, students achieve the following goals: match concepts with laser communication system parts; explain advantages of fiber optic cable over conventional copper wire;…
ProtoDESI: First On-Sky Technology Demonstration for the Dark Energy Spectroscopic Instrument
NASA Astrophysics Data System (ADS)
Fagrelius, Parker; Abareshi, Behzad; Allen, Lori; Ballester, Otger; Baltay, Charles; Besuner, Robert; Buckley-Geer, Elizabeth; Butler, Karen; Cardiel, Laia; Dey, Arjun; Duan, Yutong; Elliott, Ann; Emmet, William; Gershkovich, Irena; Honscheid, Klaus; Illa, Jose M.; Jimenez, Jorge; Joyce, Richard; Karcher, Armin; Kent, Stephen; Lambert, Andrew; Lampton, Michael; Levi, Michael; Manser, Christopher; Marshall, Robert; Martini, Paul; Paat, Anthony; Probst, Ronald; Rabinowitz, David; Reil, Kevin; Robertson, Amy; Rockosi, Connie; Schlegel, David; Schubnell, Michael; Serrano, Santiago; Silber, Joseph; Soto, Christian; Sprayberry, David; Summers, David; Tarlé, Greg; Weaver, Benjamin A.
2018-02-01
The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the universe using the baryon acoustic oscillations technique. The spectra of 35 million galaxies and quasars over 14,000 square degrees will be measured during a 5-year survey. A new prime focus corrector for the Mayall telescope at Kitt Peak National Observatory will deliver light to 5,000 individually targeted fiber-fed robotic positioners. The fibers in turn feed ten broadband multi-object spectrographs. We describe the ProtoDESI experiment, that was installed and commissioned on the 4-m Mayall telescope from 2016 August 14 to September 30. ProtoDESI was an on-sky technology demonstration with the goal to reduce technical risks associated with aligning optical fibers with targets using robotic fiber positioners and maintaining the stability required to operate DESI. The ProtoDESI prime focus instrument, consisting of three fiber positioners, illuminated fiducials, and a guide camera, was installed behind the existing Mosaic corrector on the Mayall telescope. A fiber view camera was mounted in the Cassegrain cage of the telescope and provided feedback metrology for positioning the fibers. ProtoDESI also provided a platform for early integration of hardware with the DESI Instrument Control System that controls the subsystems, provides communication with the Telescope Control System, and collects instrument telemetry data. Lacking a spectrograph, ProtoDESI monitored the output of the fibers using a fiber photometry camera mounted on the prime focus instrument. ProtoDESI was successful in acquiring targets with the robotically positioned fibers and demonstrated that the DESI guiding requirements can be met.
High speed fiber optics local area networks: Design and implementation
NASA Technical Reports Server (NTRS)
Tobagi, Fouad A.
1988-01-01
The design of high speed local area networks (HSLAN) for communication among distributed devices requires solving problems in three areas: (1) the network medium and its topology; (2) the medium access control; and (3) the network interface. Considerable progress has been made in all areas. Accomplishments are divided into two groups according to their theoretical or experimental nature. A brief summary is given in Section 2, including references to papers which appeared in the literature, as well as to Ph.D. dissertations and technical reports published at Stanford University.
Terabit Wireless Communication Challenges
NASA Technical Reports Server (NTRS)
Hwu, Shian U.
2012-01-01
This presentation briefly discusses a research effort on Terabit Wireless communication systems for possible space applications. Recently, terahertz (THz) technology (300-3000 GHz frequency) has attracted a great deal of interest from academia and industry. This is due to a number of interesting features of THz waves, including the nearly unlimited bandwidths available, and the non-ionizing radiation nature which does not damage human tissues and DNA with minimum health threat. Also, as millimeter-wave communication systems mature, the focus of research is, naturally, moving to the THz range. Many scientists regard THz as the last great frontier of the electromagnetic spectrum, but finding new applications outside the traditional niches of radio astronomy, Earth and planetary remote sensing, and molecular spectroscopy particularly in biomedical imaging and wireless communications has been relatively slow. Radiologists find this area of study so attractive because t-rays are non-ionizing, which suggests no harm is done to tissue or DNA. They also offer the possibility of performing spectroscopic measurements over a very wide frequency range, and can even capture signatures from liquids and solids. According to Shannon theory, the broad bandwidth of the THz frequency bands can be used for terabit-per-second (Tb/s) wireless communication systems. This enables several new applications, such as cell phones with 360 degrees autostereoscopic displays, optic-fiber replacement, and wireless Tb/s file transferring. Although THz technology could satisfy the demand for an extremely high data rate, a number of technical challenges need to be overcome before its development. This presentation provides an overview the state-of-the- art in THz wireless communication and the technical challenges for an emerging application in Terabit wireless systems. The main issue for THz wave propagation is the high atmospheric attenuation, which is dominated by water vapor absorption in the THz frequency band. The technical challenges in design such a system and the techniques to overcome the challenges will be discussed in this presentation.
Free-space to few-mode-fiber coupling under atmospheric turbulence.
Zheng, Donghao; Li, Yan; Chen, Erhu; Li, Beibei; Kong, Deming; Li, Wei; Wu, Jian
2016-08-08
High speed free space optical communication (FSOC) has taken advantages of components developed for fiber-optic communication systems. Recently, with the rapid development of few-mode-fiber based fiber communication systems, few-mode-fiber components might further promote their applications in FSOC system. The coupling efficiency between free space optical beam and few-mode fibers under atmospheric turbulence effect are investigated in this paper. Both simulation and experimental results show that, compared with single-mode fiber, the coupling efficiencies for a 2-mode fiber and a 4-mode fiber are improved by ~4 dB and ~7 dB respectively in the presence of medium moderate and strong turbulence. Compared with single-mode fiber, the relative standard deviation of received power is restrained by 51% and 66% respectively with a 4-mode and 2-mode fiber.
ERIC Educational Resources Information Center
Whiteside, Aimee L.
2003-01-01
This study examines the skills that recent technical communication graduates and managers believe technical communication students need before entering business and industry as new technical communicators. Through questionnaires and interviews with recent graduates and managers of technical communication departments as well as an analysis of the…
Development of optical sciences in Poland
NASA Astrophysics Data System (ADS)
Romaniuk, Ryszard S.
2013-10-01
Research and technical communities for optics, photonics and optoelectronics is grouped in this country in several organizations and institutions. These are: Photonics Society of Poland (PSP), Polish Committee of Optoelectronics of SEP, Photonics Section of KEiT PAN, Laser Club at WAT, and Optics Section of PTF. Each of these communities keeps slightly different specificity. PSP publishes a quarterly journal Photonics Letters of Poland, stimulates international cooperation, and organizes conferences during Industrial Fairs on Innovativeness. PKOpto SEP organizes didactic diploma competitions in optoelectronics. KEiT PAN takes patronage over national conferences in laser technology, optical fiber technology and communications, and photonics applications. SO-PTF has recently taken a decision to organize a cyclic event "Polish Optical Conference". The third edition of this conference PKO'2013 was held in Sandomierz on 30.06-04.07.2013. The conference scientific and technical topics include: quantum and nonlinear optics, photon physics, optic and technology of lasers and other sources of coherent radiation, optoelectronics, optical integrated circuits, optical fibers, medical optics, instrumental optics, optical spectroscopy, optical metrology, new optical materials, applications of optics, teaching in optics. This paper reviews chosen works presented during the III Polish Optical Conference (PKO'2013), representing the research efforts at different national institutions.
Professional development in optics and photonics education
NASA Astrophysics Data System (ADS)
Donnelly, Judith F.; Hanes, Fenna; Massa, Nicholas J.; Washburn, Barbara R.
2002-05-01
In recent years, several New England projects have promoted professional development and curriculum design in optics and photonics. Funded in part by the Advanced Technological Education (ATE) program of the National Science Foundation (NSF), these projects have prepared middle and high school teachers, college faculty and career counselors from more than 100 New England institutions to introduce fiber optics, telecommunications and photonics technology education. Four of these projects will be discussed here: (1) The New England Board of Higher Education's (NEBHE) Fiber Optics Technology Education Project, (FOTEP) was designed to teach fiber optics theory and to provide laboratory experiences at the secondary and postsecondary levels. (2) Springfield Technical Community College's Northeast Center for Telecommunications Technologies (NCTT) is developing curricula and instructional materials in lightwave, networking and wireless telecommunications technologies. (3) The Harvard-Smithsonian Center for Astrophysics project ComTech developed a 12-week, hands-on curriculum and teaching strategies for middle and high school science and technology teachers in telecommunications and focused on optical communication (fiber optics). (4) NEBHE's project PHOTON is preparing middle, secondary and postsecondary instructors to introduce theory and laboratory experiences in photonics, including geometric and wave optics as well as principles of lasers and photonics applications.
Production of Banana Fiber Yarns for Technical Textile Reinforced Composites
Ortega, Zaida; Morón, Moisés; Monzón, Mario D.; Badalló, Pere; Paz, Rubén
2016-01-01
Natural fibers have been used as an alternative to synthetic ones for their greener character; banana fibers have the advantage of coming from an agricultural residue. Fibers have been extracted by mechanical means from banana tree pseudostems, as a strategy to valorize banana crops residues. To increase the mechanical properties of the composite, technical textiles can be used as reinforcement, instead of short fibers. To do so, fibers must be spun and woven. The aim of this paper is to show the viability of using banana fibers to obtain a yarn suitable to be woven, after an enzymatic treatment, which is more environmentally friendly. Extracted long fibers are cut to 50 mm length and then immersed into an enzymatic bath for their refining. Conditions of enzymatic treatment have been optimized to produce a textile grade of banana fibers, which have then been characterized. The optimum treating conditions were found with the use of Biopectinase K (100% related to fiber weight) at 45 °C, pH 4.5 for 6 h, with bath renewal after three hours. The first spinning trials show that these fibers are suitable to be used for the production of yarns. The next step is the weaving process to obtain a technical fabric for composites production. PMID:28773490
Interferometric measurement of refractive index modification in a single mode microfiber
NASA Astrophysics Data System (ADS)
Ahmed, Farid; Ahsani, Vahid; Jun, Martin B. G.
2017-02-01
Efficient and cost effective measurement of the refractive index profile in an optical fiber is a significant technical job to design and manufacture in-fiber photonic devices and communication systems. For instance, to design fiber gratings, it is required to estimate the refractive index modulation to be inscribed by the fabrication apparatus such as ultraviolet or infrared lasers. Mach-Zehnder interferometer (MZI) based quantification of refractive index change written in single mode microfiber by femtosecond laser radiation is presented in this study. The MZI is constructed by splicing a microfiber (core diameter: 3.75 μm, cladding diameter: 40 μm) between standard single mode fibers. To measure the RI inscribed by infrared femtosecond laser, 200 μm length of the core within the MZI was scanned with laser radiation. As the higher index was written within 200 μm length of the core, the transmission spectrum of the interferometer displayed a corresponding red shift. The observed spectral shift was used to calculate the amount of refractive index change inscribed by the femtosecond irradiation. For the MZI length of 3.25 mm, and spectral shift of 0.8 nm, the calculated refractive index was found to be 0.00022. The reported results display excellent agreement between theory and experimental findings. Demonstrated method provides simple yet very effective on-site measurement of index change in optical fibers. Since the MZI can be constructed in diverse fiber types, this technique offers flexibility to quantify index change in various optical fibers.
Fiber distributed feedback laser
NASA Technical Reports Server (NTRS)
Elachi, C.; Evans, G. A.; Yeh, C. (Inventor)
1976-01-01
Utilizing round optical fibers as communication channels in optical communication networks presents the problem of obtaining a high efficiency coupling between the optical fiber and the laser. A laser is made an integral part of the optical fiber channel by either diffusing active material into the optical fiber or surrounding the optical fiber with the active material. Oscillation within the active medium to produce lasing action is established by grating the optical fiber so that distributed feedback occurs.
ERIC Educational Resources Information Center
Bergen County Vocational-Technical High School, Hackensack, NJ.
This project was conducted to determine the vocational, technical, and scientific skills and knowledge needed to work with the fiber optics applications that are in all areas of technology. A research assistant was hired by the project director to collect data and develop a research base for the project. Information was gathered through a…
ProtoDESI: First On-Sky Technology Demonstration for the Dark Energy Spectroscopic Instrument
Fagrelius, Parker; Abareshi, Behzad; Allen, Lori; ...
2018-01-15
The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the universe using the baryon acoustic oscillations technique. The spectra of 35 million galaxies and quasars over 14,000 square degrees will be measured during a 5-year survey. A new prime focus corrector for the Mayall telescope at Kitt Peak National Observatory will deliver light to 5,000 individually targeted fiber-fed robotic positioners. The fibers in turn feed ten broadband multi-object spectrographs. We describe the ProtoDESI experiment, that was installed and commissioned on the 4-m Mayall telescope from 2016 August 14 to September 30. ProtoDESI was anmore » on-sky technology demonstration with the goal to reduce technical risks associated with aligning optical fibers with targets using robotic fiber positioners and maintaining the stability required to operate DESI. The ProtoDESI prime focus instrument, consisting of three fiber positioners, illuminated fiducials, and a guide camera, was installed behind the existing Mosaic corrector on the Mayall telescope. A fiber view camera was mounted in the Cassegrain cage of the telescope and provided feedback metrology for positioning the fibers. ProtoDESI also provided a platform for early integration of hardware with the DESI Instrument Control System that controls the subsystems, provides communication with the Telescope Control System, and collects instrument telemetry data. In conclusion, lacking a spectrograph, ProtoDESI monitored the output of the fibers using a fiber photometry camera mounted on the prime focus instrument. ProtoDESI was successful in acquiring targets with the robotically positioned fibers and demonstrated that the DESI guiding requirements can be met.« less
ProtoDESI: First On-Sky Technology Demonstration for the Dark Energy Spectroscopic Instrument
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fagrelius, Parker; Abareshi, Behzad; Allen, Lori
The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the universe using the baryon acoustic oscillations technique. The spectra of 35 million galaxies and quasars over 14,000 square degrees will be measured during a 5-year survey. A new prime focus corrector for the Mayall telescope at Kitt Peak National Observatory will deliver light to 5,000 individually targeted fiber-fed robotic positioners. The fibers in turn feed ten broadband multi-object spectrographs. We describe the ProtoDESI experiment, that was installed and commissioned on the 4-m Mayall telescope from 2016 August 14 to September 30. ProtoDESI was anmore » on-sky technology demonstration with the goal to reduce technical risks associated with aligning optical fibers with targets using robotic fiber positioners and maintaining the stability required to operate DESI. The ProtoDESI prime focus instrument, consisting of three fiber positioners, illuminated fiducials, and a guide camera, was installed behind the existing Mosaic corrector on the Mayall telescope. A fiber view camera was mounted in the Cassegrain cage of the telescope and provided feedback metrology for positioning the fibers. ProtoDESI also provided a platform for early integration of hardware with the DESI Instrument Control System that controls the subsystems, provides communication with the Telescope Control System, and collects instrument telemetry data. In conclusion, lacking a spectrograph, ProtoDESI monitored the output of the fibers using a fiber photometry camera mounted on the prime focus instrument. ProtoDESI was successful in acquiring targets with the robotically positioned fibers and demonstrated that the DESI guiding requirements can be met.« less
NASA Technical Reports Server (NTRS)
Mathes, J. C. (Compiler); Pinelli, T. E. (Compiler)
1981-01-01
Proceeding of the technical communication sessions at the 32nd annual meeting of the Conference on College Composition and Communication held in Dallas, Texas, March 26-28, 1981 are summarized. The proceeding suggest that technical communication has become an important subfield and is becoming an intrinsic part of many undergraduate curricula. Technical communication as a separate discipline, however, is relatively new. For that reason, proceedings that can make current research available as quickly as possible are suggested for preparation. The following topics were addressed: (1) a history and definition of technical writing, (2) the case method is technical communication (3) teaching technical writing (4) oral communication and rhetorical theory, and (5) new approaches in and practical applications of technical writing.
NASA Astrophysics Data System (ADS)
Hu, Beibei; Shi, Haifeng; Zhang, Yixin
2018-06-01
We theoretically study the fiber-coupling efficiency of Gaussian-Schell model beams propagating through oceanic turbulence. The expression of the fiber-coupling efficiency is derived based on the spatial power spectrum of oceanic turbulence and the cross-spectral density function. Our work shows that the salinity fluctuation has a greater impact on the fiber-coupling efficiency than temperature fluctuation does. We can select longer λ in the "ocean window" and higher spatial coherence of light source to improve the fiber-coupling efficiency of the communication link. We also can achieve the maximum fiber-coupling efficiency by choosing design parameter according specific oceanic turbulence condition. Our results are able to help the design of optical communication link for oceanic turbulence to fiber sensor.
Thermal tuning On narrow linewidth fiber laser
NASA Astrophysics Data System (ADS)
Han, Peiqi; Liu, Tianshan; Gao, Xincun; Ren, Shiwei
2010-10-01
At present, people have been dedicated to high-speed and large-capacity optical fiber communication system. Studies have been shown that optical wavelength division multiplexing (WDM) technology is an effective means of communication to increase the channel capacity. Tunable lasers have very important applications in high-speed, largecapacity optical communications, and distributed sensing, it can provide narrow linewidth and tunable laser for highspeed optical communication. As the erbium-doped fiber amplifier has a large gain bandwidth, the erbium-doped fiber laser can be achieved lasing wavelength tunable by adding a tunable filter components, so tunable filter device is the key components in tunable fiber laser.At present, fiber laser wavelength is tuned by PZT, if thermal wavelength tuning is combined with PZT, a broader range of wavelength tuning is appearance . Erbium-doped fiber laser is used in the experiments,the main research is the physical characteristics of fiber grating temperature-dependent relationship and the fiber grating laser wavelength effects. It is found that the fiber laser wavelength changes continuously with temperature, tracking several temperature points observed the self-heterodyne spectrum and found that the changes in spectra of the 3dB bandwidth of less than 1kHz, and therefore the fiber laser with election-mode fiber Bragg grating shows excellent spectral properties and wavelength stability.
NASA Astrophysics Data System (ADS)
Biedron, William S.
1995-11-01
Since 1990 there has been a rapid increase in the demand for communication services, especially local and wide area network (LAN/WAN) oriented services. With the introduction of the DFB laser transmitter, hybrid-fiber-coax (HFC) cable plant designs, ATM transport technologies and rf modems, new LAN/WAN services can now be defined and marketed to residential and business customers over existing cable TV systems. The term metropolitan area network (MAN) can be used to describe this overall network. This paper discusses the technical components needed to provision these services as well as provides some perspectives on integration issues. Architecture at the headend and in the backbone is discussed, as well as specific service definitions and the technology issues associated with each. The TCP/IP protocol is suggested as a primary protocol to be used throughout the MAN.
NASA Astrophysics Data System (ADS)
Huang, Xu-Hong; Lu, Hai-Han; Donati, Silvano; Li, Chung-Yi; Wang, Yun-Chieh; Jheng, Yu-Bo; Chang, Jen-Chieh
2018-07-01
Two-way wireless-over-fiber and free-space optical (FSO)-over-fiber communication systems, with an optical carrier transmission for a hybrid 10 Gbps baseband data stream, are proposed and practically demonstrated. 10 Gbps/50 GHz and 10 Gbps/100 GHz millimeter-wave data signal transmissions are also proposed and practically demonstrated. An optical carrier with a 10 Gbps baseband data stream is delivered via a 50 km single-mode fiber transportation to effectively lower dispersion-induced limitation due to fiber links and distortion produced by beating among multiple optical sidebands. To our understanding, this experiment is foremost in employing an optical carrier transmission approach to a two-way wireless-over-fiber and FSO-over-fiber communication system to suppress fiber dispersion and distortion effectively. Bit error rate performs well for downlink and uplink deliveries via a 50 km single-mode fiber transportation with a 100 m FSO link/5 m RF wireless delivery. The offered two-way wireless-over-fiber and FSO-over-fiber communication system with an optical carrier transmission is a promising option. It should be interesting for signifying the progress in the integration of long-haul fiber-based trunks and short-range RF/optical wireless link-based branches.
Li, Kangning; Ma, Jing; Tan, Liying; Yu, Siyuan; Zhai, Chao
2016-06-10
The performances of fiber-based free-space optical (FSO) communications over gamma-gamma distributed turbulence are studied for multiple aperture receiver systems. The equal gain combining (EGC) technique is considered as a practical scheme to mitigate the atmospheric turbulence. Bit error rate (BER) performances for binary-phase-shift-keying-modulated coherent detection fiber-based free-space optical communications are derived and analyzed for EGC diversity receptions through an approximation method. To show the net diversity gain of a multiple aperture receiver system, BER performances of EGC are compared with a single monolithic aperture receiver system with the same total aperture area (same average total incident optical power on the aperture surface) for fiber-based free-space optical communications. The analytical results are verified by Monte Carlo simulations. System performances are also compared for EGC diversity coherent FSO communications with or without considering fiber-coupling efficiencies.
Liu, Xiang; Chandrasekhar, S; Winzer, P J; Chraplyvy, A R; Tkach, R W; Zhu, B; Taunay, T F; Fishteyn, M; DiGiovanni, D J
2012-08-13
Coherent superposition of light waves has long been used in various fields of science, and recent advances in digital coherent detection and space-division multiplexing have enabled the coherent superposition of information-carrying optical signals to achieve better communication fidelity on amplified-spontaneous-noise limited communication links. However, fiber nonlinearity introduces highly correlated distortions on identical signals and diminishes the benefit of coherent superposition in nonlinear transmission regime. Here we experimentally demonstrate that through coordinated scrambling of signal constellations at the transmitter, together with appropriate unscrambling at the receiver, the full benefit of coherent superposition is retained in the nonlinear transmission regime of a space-diversity fiber link based on an innovatively engineered multi-core fiber. This scrambled coherent superposition may provide the flexibility of trading communication capacity for performance in future optical fiber networks, and may open new possibilities in high-performance and secure optical communications.
ERIC Educational Resources Information Center
Rheam, Harry
1993-01-01
Describes simple and inexpensive labs for introducing students to fiber optic communications. Students investigate light as a carrier wave; look into the difficulties associated with "light" communication; and learn about modulation, optical fibers, and critical angles. (PR)
The composing process in technical communication
NASA Technical Reports Server (NTRS)
Masse, R. E.
1981-01-01
The theory and application of the composing process in technical communications is addressed. The composing process of engineers, some implications for composing research for the teaching and research of technical communication, and an interpretation of the processes as creative experience are also discussed. Two areas of technical communications summarized concern: the rhetorical features of technical communications, and the theoretical background for a process-based view, a problem-solving approach to technical writing.
NASA Astrophysics Data System (ADS)
Satake, Toshiaki; Nagasawa, Shinji; Hughes, Mike; Lutz, Sharon
2011-01-01
The electrical communication laboratory of NTT started the research of MT (Mechanically Transferable) connector in early 1980s. The initial goal was to realize a multi-fiber connector which can repeat low loss, stable, reliable and low-cost connections of subscriber optical fiber cable networks for more than 20 years period in the field. We review the multi-fiber alignment design with two guide pins, and following several technical improvements toward the final MT connector used in the commercial telecommunication networks. And then, we review development histories to reach to the low-loss, high-return-loss and reliable APC-MPO (Angled Physical Contact Multi-fiber Push On) connectors introduced in NTT COs and in Verizon's FTTH (Fiber To The Home) networks. In the latter half, we propose the low-loss intermateability design for connectors made by different suppliers in order to enable mass introductions into large scale systems. In addition we also describe an accurate connector loss presumption method for different lots' ferrules based on the MT ferrule dimension data before assembling the connectors. We believe with a wide intermateability of APC-MPO connector will increase its use in the fields. The APC-MPO connector manufactured based on the proposed design had low insertion losses of less than 0.25 dB at the same level of simplex connectors and the higher level of return losses higher than 65 dB.
Remote Observing with the Keck Telescope Using the ACTS Satellite
NASA Technical Reports Server (NTRS)
Cohen, Judy; Shopbell, Patrick; Bergman, Larry
1998-01-01
As a technical demonstration project for the NASA Advanced Communications Technology Satellite (ACTS), we have implemented remote observing on the 10-meter Keck II telescope on Mauna Kea in Hawaii from the California Institute of Technology campus in Pasadena. The data connection consists of optical fiber networks in Hawaii and California, connecting the end-points to high data rate (HDR) ACTS satellite antennae at JPL in Pasadena and at the Tripler Army Medical Center in Honolulu. The terrestrial fiber networks run the asynchronous transfer mode (ATM) protocol at DS-3 (45 Mbit/sec) speeds, providing ample bandwidth to enable remote observing with a software environment identical to that used for on-site observing in Hawaii. This experiment has explored the data requirements of remote observing with a modern research telescope and large-format detector arrays. While the maximum burst data rates are lower than those required for many other applications (e.g., HDTV), the network reliability and data integrity requirements are critical. As we show in this report, the former issue particularly may be the greatest challenge for satellite networks for this class of application. We have also experimented with the portability of standard TCP/IP applications to satellite networks, demonstrating the need for alternative TCP congestion algorithms and minimization of bit error rates (BER). Reliability issues aside, we have demonstrated that true remote observing over high-speed networks provides several important advantages over standard observing paradigms. Technical advantages of the high-speed network access include more rapid download of data to a user's home institution and the opportunity for alternative communication facilities between members of an observing team, such as audio- and videoconferencing.
High frequency optical communications; Proceedings of the Meeting, Cambridge, MA, Sept. 23, 24, 1986
NASA Astrophysics Data System (ADS)
Ramer, O. Glenn; Sierak, Paul
Topics discussed in this volume include systems and applications, detectors, sources, and coherent communications. Papers are presented on RF fiber optic links for avionics applications, fiber optics and optoelectronics for radar and electronic warfare applications, symmetric coplanar electrodes for high-speed Ti:LiNbO3 devices, and surface wave electrooptic modulator. Attention is given to X-band RF fiber-optic links, fiber-optic links for microwave signal transmission, GaAs monolithic receiver and laser driver for GHz transmission rates, and monolithically integrable high-speed photodetectors. Additional papers are on irregular and chaotic behavior of semiconductor lasers under modulation, high-frequency laser package for microwave optical communications, receiver modeling for coherent light wave communications, and polarization sensors and controllers for coherent optical communication systems.
The Impact Of Multimode Fiber Chromatic Dispersion On Data Communications
NASA Astrophysics Data System (ADS)
Hackert, Michael J.
1990-01-01
Capability for the lowest cost is the goal of contemporary communications managers. With all of the competitive pressures that modern businesses are experiencing these days, communications needs must be met with the most information carrying capacity for the lowest cost. Optical fiber communication systems meet these requirements while providing reliability, system integrity, and potential future upgradability. Consequently, optical fiber is finding numerous applications in addition to its traditional telephony plant. Fiber based systems are meeting these requirements in building networks and computer interconnects at a lower cost than copper based systems. A fiber type being chosen by industry to meet these needs in standard systems such as FDDI, is multimode fiber. Multimode fiber systems offer cost advantages over single-mode fiber through lower fiber connection costs. Also, system designers can gain savings by using low cost, high reliability, wide spectral width sources such as LEDs instead of lasers and by operating at higher bit rates than used for multimode systems in the past. However, in order to maximize the cost savings while ensuring the system will operate as intended, the chromatic dispersion of the fiber must be taken into account. This paper explains how to do that and shows how to calculate multimode chromatic dispersion for each of the standard fiber sizes (50 μm, 62.5 μm, 85 μm, and 100μm core diameter).
NASA Astrophysics Data System (ADS)
Romaniuk, Ryszard S.
2012-05-01
This paper is the fourth part (out of five) of the research survey of WILGA Symposium work, May 2012 Edition, concerned with Optoelectronic Devices, Sensors, Communication and Multimedia (Video and Audio) technologies. It presents a digest of chosen technical work results shown by young researchers from different technical universities from this country during the Jubilee XXXth SPIE-IEEE Wilga 2012, May Edition, symposium on Photonics and Web Engineering. Topical tracks of the symposium embraced, among others, nanomaterials and nanotechnologies for photonics, sensory and nonlinear optical fibers, object oriented design of hardware, photonic metrology, optoelectronics and photonics applications, photonics-electronics co-design, optoelectronic and electronic systems for astronomy and high energy physics experiments, JET tokamak and pi-of-the sky experiments development. The symposium is an annual summary in the development of numerable Ph.D. theses carried out in this country in the area of advanced electronic and photonic systems. It is also a great occasion for SPIE, IEEE, OSA and PSP students to meet together in a large group spanning the whole country with guests from this part of Europe. A digest of Wilga references is presented [1-270].
NASA Technical Reports Server (NTRS)
Kohl, John R.; Barclay, Rebecca O.; Pinelli, Thomas E.; Keene, Michael L.; Kennedy, John M.
1993-01-01
One of the most significant developments in the field of technical communication during the 1980's and 1990's has been a growing interest in international technical communication, including technical communication in Japan. This article provides insights into aspects of the Japanese language and culture that affect Japanese technical communication practices. These insights are then used to interpret and report the results of a survey of Japanese aerospace engineers and scientists concerning the kinds of communication products they produce, the kinds they use, and the specific recommendation they would offer to designers of academic programs in technical communication.
NASA Technical Reports Server (NTRS)
Kohl, John R.; Barclay, Rebecca O.; Pinelli, Thomas E.; Keene, Michael L.; Kennedy, John M.
1993-01-01
One of the most significant developments in the field of technical communication during the 1980s and 1990s has been a growing interest in international technical communication, including technical communication in Japan. This article provides insights into aspects of the Japanese language and culture that affect Japanese technical communication practices. The authors then use these insights to interpret and report the results of a survey of Japanese aerospace engineers and scientists concerning the kinds of communication products they produce, the kinds they use, and the specific recommendations they would offer to designers of academic programs in technical communication.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Holland, Maurita Peterson; Keene, Michael L.; Kennedy, John M.
1991-01-01
Aerospace engineers and scientists from Western Europe, Japan, and the United States were surveyed as part of the NASA/DoD Aerospace Knowledge Diffusion Research Project. Questionnaires were used to solicit their opinions regarding the following: (1) the importance of technical communications to their profession; (2) the use and production of technical communications; and (3) their views about the appropriate content of an undergraduate course in technical communications. The ability to communicate technical information effectively was very important to the aerospace engineers and scientists who participated in the study. A considerable portion of their working week is devoted to using and producing technical information. The types of technical communications used and produced varied within and among the three groups. The type of technical communication product used and produced appears to be related to respondents' professional duties. Respondents from the three groups made similar recommendations regarding the principles, mechanics, and on-the-job communications to be included in an undergraduate technical communications course for aerospace majors.
On-Board Fiber-Optic Network Architectures for Radar and Avionics Signal Distribution
NASA Technical Reports Server (NTRS)
Alam, Mohammad F.; Atiquzzaman, Mohammed; Duncan, Bradley B.; Nguyen, Hung; Kunath, Richard
2000-01-01
Continued progress in both civil and military avionics applications is overstressing the capabilities of existing radio-frequency (RF) communication networks based on coaxial cables on board modem aircrafts. Future avionics systems will require high-bandwidth on- board communication links that are lightweight, immune to electromagnetic interference, and highly reliable. Fiber optic communication technology can meet all these challenges in a cost-effective manner. Recently, digital fiber-optic communication systems, where a fiber-optic network acts like a local area network (LAN) for digital data communications, have become a topic of extensive research and development. Although a fiber-optic system can be designed to transport radio-frequency (RF) signals, the digital fiber-optic systems under development today are not capable of transporting microwave and millimeter-wave RF signals used in radar and avionics systems on board an aircraft. Recent advances in fiber optic technology, especially wavelength division multiplexing (WDM), has opened a number of possibilities for designing on-board fiber optic networks, including all-optical networks for radar and avionics RF signal distribution. In this paper, we investigate a number of different novel approaches for fiber-optic transmission of on-board VHF and UHF RF signals using commercial off-the-shelf (COTS) components. The relative merits and demerits of each architecture are discussed, and the suitability of each architecture for particular applications is pointed out. All-optical approaches show better performance than other traditional approaches in terms of signal-to-noise ratio, power consumption, and weight requirements.
NASA Technical Reports Server (NTRS)
Workman, Gary L.; Smith, Guy A.; OBrien, Sue; Adcock, Leonard
1998-01-01
The fiber optics industry has grown into a multi-billion marketplace that will continue to grow into the 21st century. Optical fiber communications is currently dominated by silica glass technology. Successful efforts to improve upon the low loss transmission characteristics of silica fibers have propelled the technology into the forefront of the communications industry. However, reaching the theoretical transmission capability of silica fiber through improved processing has still left a few application areas in which other fiber systems can provide an influential role due to specific characteristics of high theoretical transmission in the 2 - 3 micron wavelength region. One of the other major materials used for optical fibers is the systems based upon Heavy Metal Fluoride Glass (HMFG). Commercial interest is driven primarily by the potential for low loss repeaterless infrared fibers. An example of the major communications marketplace which would benefit from the long distance repeaterless capability of infrared fibers is the submarine cables which link the continents. When considering commercial interests, optical fiber systems provide a healthy industrial position which continues to expand. Major investments in the systems used for optical fiber communications have continued to increase each year and are predicted to continue well into the next century. Estimates of 8.5% compounded annually are predicted through 1999 for the North American market and 1 1 % worldwide. The growth for the optical fiber cable itself is expected to continue between 44 and 50 per cent of the optical fiber communications budget through 1999. The total budget in 1999 world-wide is expected to be in the neighborhood of $9 billion. Another survey predicts that long haul telecommunications represents 15% of a world-wide fiber optics market in 1998. The actual amount allotted to cable was not specified. However, another market research had predicted that the cable costs alone represents more than 50% of the total budget each year through 1998. A newly emerging activity is the commercial development of doped optical fibers which can be pumped by laser diodes to provide amplification of the communication signals. This technology is newly emerging and will be developed for commercial interests in the United States by Galileo Electro-optical Incorporated in Sturbridge, MA on a license from British Telecom. Long repeaterless communication links provide the biggest stimulus for this technology. As an example of the of the revenues involved in the optical fiber communications 3 industry, the current trade journal lists that for the fiscal years, 1991 - 1994, 185 separate undersea links were established. In addition, another 105 links are planned through 1998. The distribution of revenues involved in the undersea installations is roughly $8.5 billion through 1993 and another $13 billion planned through 1998. A large portion of the future activity (34%) is planned for Southeast Asia and the Pacific Region. Other examples of the commercial utility of optical fiber networks is given in a recent scientific symposium in which the outlook for HMFG infrared fiber was determined to be very bright.Another area of interest lies in the use of fiber optics for laser surgery delivery systems.
Zhu, Long; Wang, Andong; Chen, Shi; Liu, Jun; Mo, Qi; Du, Cheng; Wang, Jian
2017-10-16
Twisted light carrying orbital angular momentum (OAM) is a special kind of structured light that has a helical phase front, a phase singularity, and a doughnut intensity profile. Beyond widespread developments in manipulation, microscopy, metrology, astronomy, nonlinear and quantum optics, OAM-carrying twisted light has seen emerging application of optical communications in free space and specially designed fibers. Instead of specialty fibers, here we show the direct use of a conventional graded-index multi-mode fiber (MMF) for OAM communications. By exploiting fiber-compatible mode exciting and filtering elements, we excite the first four OAM mode groups in an MMF. We demonstrate 2.6-km MMF transmission using four data-carrying OAM mode groups (OAM 0,1 , OAM +1,1 /OAM -1,1 , OAM +2,1 , OAM +3,1 ). Moreover, we demonstrate two data-carrying OAM mode groups multiplexing transmission over the 2.6-km MMF with low-level crosstalk free of multiple-input multiple-output digital signal processing (MIMO-DSP). The demonstrations may open up new perspectives to fiber-based OAM communication/non-communication applications using already existing conventional fibers.
Washable hydrophobic smart textiles and multi-material fibers for wireless communication
NASA Astrophysics Data System (ADS)
Gorgutsa, Stepan; Bachus, Kyle; LaRochelle, Sophie; Oleschuk, Richard D.; Messaddeq, Younes
2016-11-01
This paper reports on the performance and environmental endurance of the recently presented wirelessly communicating smart textiles with integrated multi-material fiber antennas. Metal-glass-polymer fiber composites were fabricated using sub-1 mm hollow-core silica fibers and liquid state silver deposition technique. These fibers were then integrated into textiles in the form of center-fed dipole and loop antennas during standard weaving procedure. Fiber antennas performance was found to be directly comparable to classic ‘rigid’ solutions in terms of return loss, gain and radiation patterns, which allowed transmitting data through Bluetooth protocol at 2.4 GHz frequency. Applied superhydrophobic coatings (water contact angle = 152°, sliding angle = 6°) allow uninterrupted wireless communication of the textiles under direct water application even after multiple washing cycles.
Fiber optic signal amplifier using thermoelectric power generation
Hart, M.M.
1993-01-01
A remote fiber optic signal amplifier for use as a repeater/amplifier, such as in transoceanic communication, powered by a Pu{sub 238} or Sr{sub 90} thermoelectric generator. The amplifier comprises a unit with connections on the receiving and sending sides of the communications system, and an erbium-doped fiber amplifier connecting each sending fiber to each receiving fiber. The thermoelectric generator, preferably a Pu{sub 238} or Sr{sub 90} thermoelectric generator delivers power to the amplifiers through a regulator. The heat exchange surfaces of the thermoelectric generator are made of material resistant to corrosion and biological growth and are directly exposed to the outside, such as the ocean water in transoceanic communications.
Fiber optic signal amplifier using thermoelectric power generation
Hart, M.M.
1995-04-18
A remote fiber optic signal amplifier for use as a repeater/amplifier, such as in transoceanic communications, powered by a Pu{sub 238} or Sr{sub 90} thermoelectric generator. The amplifier comprises a unit with connections on the receiving and sending sides of the communications system, and an erbium-doped fiber amplifier connecting each sending fiber to each receiving fiber. The thermoelectric generator, preferably a Pu{sub 238} or Sr{sub 90} thermoelectric generator delivers power to the amplifiers through a regulator. The heat exchange surfaces of the thermoelectric generator are made of materials resistant to corrosion and biological growth and are directly exposed to the outside, such as the ocean water in transoceanic communications. 2 figs.
Fiber optic signal amplifier using thermoelectric power generation
Hart, Mark M.
1995-01-01
A remote fiber optic signal amplifier for use as a repeater/amplifier, such as in transoceanic communications, powered by a Pu.sub.238 or Sr.sub.90 thermoelectric generator. The amplifier comprises a unit with connections on the receiving and sending sides of the communications system, and an erbium-doped fiber amplifier connecting each sending fiber to each receiving fiber. The thermoelectric generator, preferably a Pu.sub.238 or Sr.sub.90 thermoelectric generator delivers power to the amplifiers through a regulator. The heat exchange surfaces of the thermoelectric generator are made of materials resistant to corrosion and biological growth and are directly exposed to the outside, such as the ocean water in transoceanic communications.
Fiber-coupling efficiency for free-space optical communication through atmospheric turbulence.
Dikmelik, Yamaç; Davidson, Frederic M
2005-08-10
High-speed free-space optical communication systems have recently used fiber-optic components. The received laser beam in such a system must be coupled into a single-mode fiber at the input of the receiver module. However, propagation through atmospheric turbulence degrades the spatial coherence of a laser beam and limits the fiber-coupling efficiency. We numerically evaluate the fiber-coupling efficiency for laser light distorted by atmospheric turbulence. We also investigate the use of a coherent fiber array as a receiver structure and find that a coherent fiber array that consists of seven subapertures would significantly increase the fiber-coupling efficiency.
On a two-pass scheme without a faraday mirror for free-space relativistic quantum cryptography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kravtsov, K. S.; Radchenko, I. V.; Korol'kov, A. V.
2013-05-15
The stability of destructive interference independent of the input polarization and the state of a quantum communication channel in fiber optic systems used in quantum cryptography plays a principal role in providing the security of communicated keys. A novel optical scheme is proposed that can be used both in relativistic quantum cryptography for communicating keys in open space and for communicating them over fiber optic lines. The scheme ensures stability of destructive interference and admits simple automatic balancing of a fiber interferometer.
Getting Personal: Individuality, Innovation, and Technical Communication.
ERIC Educational Resources Information Center
Steiner, Carol J.
1999-01-01
Suggests that effective communication between technical and nontechnical people is difficult because technical communication lacks a personal dimension: technical people give up their identity to be considered competent. Argues that a different approach to communication education for scientists, engineers, and technologists is required to equip…
Technical Communication, Knowledge Management, and XML.
ERIC Educational Resources Information Center
Applen, J. D.
2002-01-01
Describes how technical communicators can become involved in knowledge management. Examines how technical communicators can teach organizations to design, access, and contribute to databases; alert them to new information; and facilitate trust and sharing. Concludes that successful technical communicators would do well to establish a culture that…
ERIC Educational Resources Information Center
Moore, Patrick
2006-01-01
Carolyn Miller's oft-cited "Humanistic Rationale for Technical Writing," published in 1979, tries to give technical communication faculty more cultural capital in English departments controlled by literature professors. Miller replaces a positivistic emphasis in technical communication pedagogy with rhetoric. She shows how technical knowledge is…
ERIC Educational Resources Information Center
Reese, Susan
2003-01-01
Describes the fiber optics programs at the Career and Technical Center in Berlin, Pennsylvania and the Charles S. Monroe Technology Center in Loudoun County, Virginia. Discusses the involvement of the Fiber Optic Association with education, research and development, manufacturing, sales, distribution, installation, and maintenance of fiber optic…
NASA Astrophysics Data System (ADS)
The subjects discussed are related to LSI/VLSI based subscriber transmission and customer access for the Integrated Services Digital Network (ISDN), special applications of fiber optics, ISDN and competitive telecommunication services, technical preparations for the Geostationary-Satellite Orbit Conference, high-capacity statistical switching fabrics, networking and distributed systems software, adaptive arrays and cancelers, synchronization and tracking, speech processing, advances in communication terminals, full-color videotex, and a performance analysis of protocols. Advances in data communications are considered along with transmission network plans and progress, direct broadcast satellite systems, packet radio system aspects, radio-new and developing technologies and applications, the management of software quality, and Open Systems Interconnection (OSI) aspects of telematic services. Attention is given to personal computers and OSI, the role of software reliability measurement in information systems, and an active array antenna for the next-generation direct broadcast satellite.
DOT National Transportation Integrated Search
1996-04-01
The advent of fiber-optic communications technology coupled with continued rapid growth in demand for communications capacity have led private communications companies to seek to build new, and extend existing, fiber-optics networks. There is increas...
Achieving Hydrogen Storage Goals through High-Strength Fiber Glass - Final Technical Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Hong; Johnson, Kenneth I.; Newhouse, Norman L.
Led by PPG and partnered with Hexagon Lincoln and Pacific Northwest National Laboratory (PNNL), the team recently carried out a project “Achieving Hydrogen Storage Goals through High-Strength Fiber Glass”. The project was funded by DOE’s Fuel Cell Technologies office within the Office of Energy Efficiency and Renewable Energy, starting on September 1, 2014 as a two-year project to assess technical and commercial feasibilities of manufacturing low-cost, high-strength glass fibers to replace T700 carbon fibers with a goal of reducing the composite total cost by 50% of the existing, commercial 700 bar hydrogen storage tanks used in personal vehicles.
850-nm hybrid fiber/free-space optical communications using orbital angular momentum modes.
Jurado-Navas, Antonio; Tatarczak, Anna; Lu, Xiaofeng; Olmos, Juan José Vegas; Garrido-Balsells, José María; Monroy, Idelfonso Tafur
2015-12-28
Light beams can carry orbital angular momentum (OAM) associated to the helicity of their phasefronts. These OAM modes can be employed to encode information onto a laser beam for transmitting not only in a fiber link but also in a free-space optical (FSO) one. Regarding this latter scenario, FSO communications are considered as an alternative and promising mean complementing the traditional optical communications in many applications where the use of fiber cable is not justified. This next generation FSO communication systems have attracted much interest recently, and the inclusion of beams carrying OAM modes can be seen as an efficient solution to increase the capacity and the security in the link. In this paper, we discuss an experimental demonstration of a proposal for next generation FSO communication system where a light beam carrying different OAM modes and affected by ℳ turbulence is coupled to the multimode fiber link. In addition, we report a better and more robust behavior of higher order OAM modes when the intermodal dispersion is dominant in the fiber after exceeding its maximum range of operation.
Towards coherent combination of 61 fiber amplifiers
NASA Astrophysics Data System (ADS)
Heilmann, Anke; Le Dortz, Jérémy; Daniault, Louis; Fsaifes, Ihsan; Bellanger, Séverine; Antier, Marie; Bourderionnet, Jérôme; Larat, Christian; Lallier, Eric; Durand, Eric; Brignon, Arnaud; Simon-Boisson, Christophe; Chanteloup, Jean-Christophe
2018-02-01
The XCAN project aims at the coherent combination of 61 fiber amplifiers in the femtosecond regime. An important intermediate step towards this goal is the implementation of a seven fiber test setup, which allows to address key scientific and technical challenges which might occur in the scaled version of 61 fibers. This work includes the design and characterization of a support unit able to hold 61 fibers with the high precision required for an efficient coherent combination in tiled aperture configuration. This configuration, in combination with an interferometric phase measurement and active phase control, is particularly well suited for the coherent combination of a very large number of beams. Our first preliminary results with seven fibers include a combination efficiency of 30 % and a residual phase error between two fibers as low as λ/40 rms. Experiments conducted with three fibers in order to evaluate technical improvements revealed an increase of efficiency to 54 %. The combined beam was temporally compressed to 225 fs, which is Fourier transform limited with respect to the measured spectrum.
Research and education on fiber-based materials for nanofluidics at Clemson University
NASA Astrophysics Data System (ADS)
Kornev, Konstantin G.
2007-11-01
Advanced materials and the science and engineering related to their design, process, test and manufacture represents one of the fast growing sectors of the Materials Science and Engineering field. Awareness of existing process, performance, manufacturing or recycle-ability issues and limitations, often dictates the next generation of advances needed to improve existing or create new materials. To compete in this growing science and technology area, trained experts must possess strong academic skills in their discipline as well as advanced communication, networking and cultural teamwork experience. Clemson's School of Materials Science and Engineering (MSE), is continuing to expand our program to focus on unique capabilities which support local, regional and national needs in advanced materials. Specifically, MSE at Clemson is evolving to highlight intrinsic strengths in research and education areas related to optical materials, advanced fibers and composites (based on inorganic, organic and natural fibers), biomaterials and devices, and architectural and restoration material science (including the conservation and preservation of maritime structures). Additionally, we continue to invest in our expertise in materials design and fabrication, which has historically supported our well known programs in ceramics and textiles. In addition to a brief review of the School's forward-looking challenges to remain competitive among strong southeast regional materials science programs, this presentation will also highlight recent technical advances in fiber-based materials for nanofluidic applications. Specifically we will present recent results on design of fiber-based nanofluidics for sensor applications and we will discuss some physical phenomena associated with liquid transport at nanoscale.
The Roles of Technical Communication Researchers in Design Scholarship
ERIC Educational Resources Information Center
Sánchez, Fernando
2017-01-01
Design has come to be understood as an essential aspect of the work that technical communicators claim. As a result, research in the field of technical communication has approached studies of design in numerous ways. This article showcases how technical communication researchers assume the roles of observers, testers, critics, creators, and…
An Interdisciplinary Program in Technical Communications: Problems Encountered.
ERIC Educational Resources Information Center
Eckman, Martha
The need for experts in technical communication is growing significantly while the number of college graduates in the field accounts for less than one percent of the need. Three major types of problems should be considered in trying to establish a technical communication program: those involving society's need for better technical communicators,…
ERIC Educational Resources Information Center
Allen, Jo
1991-01-01
Presents an overview of research and unanswered questions related to gender issues in technical communication. Addresses the consequences of the feminization of technical communication, research on gender differences in technical communication, and the means for encouraging a more gender-balanced view of business and industry. (SR)
Scalable Optical-Fiber Communication Networks
NASA Technical Reports Server (NTRS)
Chow, Edward T.; Peterson, John C.
1993-01-01
Scalable arbitrary fiber extension network (SAFEnet) is conceptual fiber-optic communication network passing digital signals among variety of computers and input/output devices at rates from 200 Mb/s to more than 100 Gb/s. Intended for use with very-high-speed computers and other data-processing and communication systems in which message-passing delays must be kept short. Inherent flexibility makes it possible to match performance of network to computers by optimizing configuration of interconnections. In addition, interconnections made redundant to provide tolerance to faults.
Ethics in Technical Communication. The Allyn & Bacon Series in Technical Communication.
ERIC Educational Resources Information Center
Dombrowski, Paul
Arguing that ethics is an important part of technical communication, this book discusses ethics in the broad sense including not only the act of communication but also where technical information came from and how it likely will be used. It is intended for advanced undergraduate and graduate audiences, and assumes some familiarity with technical…
ERIC Educational Resources Information Center
Pinelli, Thomas E.; And Others
1991-01-01
Reports on results from 260 aerospace engineers and scientists in United States, Europe, and Japan regarding their opinions about professional importance of technical communications; generation and utilization of technical communications; and relevant content of an undergraduate course in technical communications. The fields of cryogenics,…
ERIC Educational Resources Information Center
Jones, Natasha N.
2016-01-01
This article argues for the need for a social justice approach to technical communication research and pedagogy. Given previous calls by scholars in technical and professional communication (TPC) for an attention to diversity, inclusion, and equality, the author examines the place and purpose of social justice in TPC and provides useful approaches…
Optical fiber design with orbital angular momentum light purity higher than 99.9.
Zhang, Zhishen; Gan, Jiulin; Heng, Xiaobo; Wu, Yuqing; Li, Qingyu; Qian, Qi; Chen, Dongdan; Yang, Zhongmin
2015-11-16
The purity of the synthesized orbital-angular-momentum (OAM) light in the fiber is inversely proportional to channel crosstalk level in the OAM optical fiber communication system. Here the relationship between the fiber structure and the purity is firstly demonstrated in theory. The graded-index optical fiber is proposed and designed for the OAM light propagation with the purity higher than 99.9%. 16 fiber modes (10 OAM modes) have been supported by a specific designed graded-index optical fiber with dispersion less than 35 ps/(km∙nm). Such fiber design has suppressed the intrinsic crosstalk to be lower than -30 dB, and can be potentially used for the long distance OAM optical communication system.
A hybrid quantum eraser scheme for characterization of free-space and fiber communication channels
NASA Astrophysics Data System (ADS)
Nape, Isaac; Kyeremah, Charlotte; Vallés, Adam; Rosales-Guzmán, Carmelo; Buah-Bassuah, Paul K.; Forbes, Andrew
2018-02-01
We demonstrate a simple projective measurement based on the quantum eraser concept that can be used to characterize the disturbances of any communication channel. Quantum erasers are commonly implemented as spatially separated path interferometric schemes. Here we exploit the advantages of redefining the which-path information in terms of spatial modes, replacing physical paths with abstract paths of orbital angular momentum (OAM). Remarkably, vector modes (natural modes of free-space and fiber) have a non-separable feature of spin-orbit coupled states, equivalent to the description of two independently marked paths. We explore the effects of fiber perturbations by probing a step-index optical fiber channel with a vector mode, relevant to high-order spatial mode encoding of information for ultra-fast fiber communications.
Novel Wireless-Communicating Textiles Made from Multi-Material and Minimally-Invasive Fibers
Gorgutsa, Stepan; Bélanger-Garnier, Victor; Ung, Bora; Viens, Jeff; Gosselin, Benoit; LaRochelle, Sophie; Messaddeq, Younes
2014-01-01
The ability to integrate multiple materials into miniaturized fiber structures enables the realization of novel biomedical textile devices with higher-level functionalities and minimally-invasive attributes. In this work, we present novel textile fabrics integrating unobtrusive multi-material fibers that communicate through 2.4 GHz wireless networks with excellent signal quality. The conductor elements of the textiles are embedded within the fibers themselves, providing electrical and chemical shielding against the environment, while preserving the mechanical and cosmetic properties of the garments. These multi-material fibers combine insulating and conducting materials into a well-defined geometry, and represent a cost-effective and minimally-invasive approach to sensor fabrics and bio-sensing textiles connected in real time to mobile communications infrastructures, suitable for a variety of health and life science applications. PMID:25325335
Novel wireless-communicating textiles made from multi-material and minimally-invasive fibers.
Bélanger-Garnier, Victor; Gorgutsa, Stephan; Ung, Bora; Viens, Jeff; Gosselin, Benoit; LaRochelle, Sophie; Messaddeq, Younes
2014-01-01
The ability to integrate multiple materials into miniaturized fiber structures enables the realization of novel biomedical textile devices with higher-level functionalities and minimally-invasive attributes. In this work, we present novel textile fabrics integrating unobtrusive multi-material fibers that communicate through 2.4 GHz wireless networks with excellent signal quality. The conductor elements of the textiles are embedded within the fibers themselves, providing electrical and chemical shielding against the environment, while preserving the mechanical and cosmetic properties of the garments. These multi-material fibers combine insulating and conducting materials into a well-defined geometry, and represent a cost-effective and minimally-invasive approach to sensor fabrics and bio-sensing textiles connected in real time to mobile communications infrastructures, suitable for a variety of health and life science applications.
Novel wireless-communicating textiles made from multi-material and minimally-invasive fibers.
Gorgutsa, Stepan; Bélanger-Garnier, Victor; Ung, Bora; Viens, Jeff; Gosselin, Benoit; LaRochelle, Sophie; Messaddeq, Younes
2014-10-16
The ability to integrate multiple materials into miniaturized fiber structures enables the realization of novel biomedical textile devices with higher-level functionalities and minimally-invasive attributes. In this work, we present novel textile fabrics integrating unobtrusive multi-material fibers that communicate through 2.4 GHz wireless networks with excellent signal quality. The conductor elements of the textiles are embedded within the fibers themselves, providing electrical and chemical shielding against the environment, while preserving the mechanical and cosmetic properties of the garments. These multi-material fibers combine insulating and conducting materials into a well-defined geometry, and represent a cost-effective and minimally-invasive approach to sensor fabrics and bio-sensing textiles connected in real time to mobile communications infrastructures, suitable for a variety of health and life science applications.
Two classes of capillary optical fibers: refractive and photonic
NASA Astrophysics Data System (ADS)
Romaniuk, Ryszard S.
2008-11-01
This paper is a digest tutorial on some properties of capillary optical fibers (COF). Two basic types of capillary optical fibers are clearly distinguished. The classification is based on propagation mechanism of optical wave. The refractive, singlemode COF guides a dark hollow beam of light (DHB) with zero intensity on fiber axis. The photonic, singlemode COF carries nearly a perfect axial Gaussian beam with maximum intensity on fiber axis. A subject of the paper are these two basic kinds of capillary optical fibers of pure refractive and pure photonic mechanism of guided wave transmission. In a real capillary the wave may be transmitted by a mixed mechanism, refractive and photonic, with strong interaction of photonic and refractive guided wave modes. Refractive capillary optical fibers are used widely for photonic instrumentation applications, while photonic capillary optical fibers are considered for trunk optical communications. Replacement of classical, single mode, dispersion shifted, 1550nm optimized optical fibers for communications with photonic capillaries would potentially cause a next serious revolution in optical communications. The predictions say that such a revolution may happen within this decade. This dream is however not fulfilled yet. The paper compares guided modes in both kinds of optical fiber capillaries: refractive and photonic. The differences are emphasized indicating prospective application areas of these fibers.
Thermal Diffusivity and Conductivity in Ceramic Matrix Fiber Composite Materials - Literature Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
R.G. Quinn
A technical literature review was conducted to gain an understanding of the state of the art method, problems, results, and future of thermal diffusivity/conductivity of matrix-fiber composites for high temperature applications. This paper summarizes the results of test method development and theory. Results from testing on various sample types are discussed with concentration on the anisotropic characteristics of matrix-fiber composites, barriers to heat flow, and notable microstructure observations. The conclusion presents some observations from the technical literature, drawbacks of current information and discusses potential needs for future testing.
Fiber Optic Communication System For Medical Images
NASA Astrophysics Data System (ADS)
Arenson, Ronald L.; Morton, Dan E.; London, Jack W.
1982-01-01
This paper discusses a fiber optic communication system linking ultrasound devices, Computerized tomography scanners, Nuclear Medicine computer system, and a digital fluoro-graphic system to a central radiology research computer. These centrally archived images are available for near instantaneous recall at various display consoles. When a suitable laser optical disk is available for mass storage, more extensive image archiving will be added to the network including digitized images of standard radiographs for comparison purposes and for remote display in such areas as the intensive care units, the operating room, and selected outpatient departments. This fiber optic system allows for a transfer of high resolution images in less than a second over distances exceeding 2,000 feet. The advantages of using fiber optic cables instead of typical parallel or serial communication techniques will be described. The switching methodology and communication protocols will also be discussed.
Fibercore AstroGain fiber: multichannel erbium doped fibers for optical space communications
NASA Astrophysics Data System (ADS)
Hill, Mark; Gray, Rebecca; Hankey, Judith; Gillooly, Andy
2014-03-01
Fibercore have developed AstroGainTM fiber optimized for multichannel amplifiers used in optical satellite communications and control. The fiber has been designed to take full advantage of the photo-annealing effect that results from pumping in the 980nm region. The proprietary trivalent structure of the core matrix allows optimum recovery following radiation damage to the fiber, whilst also providing a market leading Erbium Doped Fiber Amplifier (EDFA) efficiency. Direct measurements have been taken of amplifier efficiency in a multichannel assembly, which show an effective photo-annealing recovery of up to 100% of the radiation induced attenuation through excitation of point defects.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Glassman, Myron; Oliu, Walter E.; Barclay, Rebecca O.
1989-01-01
A study was undertaken that explored several aspects of technical communications in aeronautics. The study, which utilized survey research in the form of a self-administered questionnaire, was sent to 2,000 randomly selected members of the American Institute of Aeronautics and Astronautics. Six hundred and six usable questionnaires (30.3 percent) were received by the established cut off date. The study had five objectives. The first was to solicit the opinions of aeronautical engineers and scientists regarding the importance of technical communications to their profession; second, to determine their use and production of technical communications; third, to seek their views on the content of an undergraduate course in technical communications; fourth, to determine their use of libraries/technical information centers; and finally, to determine the use and importance of computer and information technology to them. The findings add considerable information to the knowledge of technical communications practices among aeronautical engineers and scientists and reinforce some of the conventional wisdom about technical communications and question other widely-held notions.
Design of oil pipeline leak detection and communication system based on optical fiber technology
NASA Astrophysics Data System (ADS)
Tu, Yaqing; Chen, Huabo
1999-08-01
The integrity of oil pipeline is always a major concern of operators. Pipeline leak not only leads to loss of oil, but pollutes environment. A new pipeline leak detection and communication system based on optical fiber technology to ensure the pipeline reliability is presented. Combined direct leak detection method with an indirect one, the system will greatly reduce the rate of false alarm. According, to the practical features of oil pipeline,the pipeline communication system is designed employing the state-of-the-art optic fiber communication technology. The system has such feature as high location accuracy of leak detection, good real-time characteristic, etc. which overcomes the disadvantages of traditional leak detection methods and communication system effectively.
ERIC Educational Resources Information Center
Ding, Daniel D.
2018-01-01
Very few articles exist that document technical communication in Hungary. My Fulbright research reveals two general points: First, technical communication pedagogy stresses correct use of professional terms and phrases in technical translations or technical articles for fictional audiences. Second, it does not emphasize the importance of…
ERIC Educational Resources Information Center
Carliner, Saul
1992-01-01
Cites reasons for pursuing a curriculum in technical communication, lists objectives a program should achieve, and outlines a four-part program that includes theory, professional skills, technical proficiency, and an internship. Lists schools offering programs in technical communication. (SR)
A simple gold-coated microstructure fiber polarization filter in two communication windows
NASA Astrophysics Data System (ADS)
Feng, Xinxing; Li, Shuguang; Du, Huijing; Zhang, Yinan; Liu, Qiang
2018-03-01
A polarization filter is designed at two communication windows of 1310 and 1550 nm based on microstructured optical fiber. The model has four large diameter air holes and two gold-coated air holes. The influence of the geometrical parameters of the photonic crystal fiber on the performance of the polarization filter is analyzed by the finite element method. The numerical simulation shows that when the fiber length is 300 μm, the corresponding extinction ratio is 209.7 dB and 179.8 dB, the bandwidth of extinction ratio (ER) better than 20 dB is 150 nm and 350 nm at the communication wavelength of 1310 nm and 1550 nm.
NASA Astrophysics Data System (ADS)
Matveeva, Tatiana U.; Osadchiy, Igor S.; Husnutdinova, Marina N.
2017-04-01
The article examines the process of formation of communicative competencies of optic and fiber optic communication systems specialists; the role of communicative competencies is examined in the structure of professionally important skills, together with the contents of professional activity. The stages of empirical research into formation of communicative competencies have been presented, and the values of statistical reliability of data have been provided. The model of formation of communicative competency using interactive technology has been developed based on the research done, and main stages of model implementation and motives of formation of communicative competency have been highlighted. A scheme of "Communicative competence as a base of future success" training session has been suggested as one of the basic interactive technologies. Main components of education that are used during the stages of the training cycle have been examined. The statistical data on the effectiveness of use of interactive educational technologies has been presented; it allowed development of communicative competency of specialists in the field of optical and fiber optic communication system.
NASA Astrophysics Data System (ADS)
Najda, Stephen P.; Perlin, Piotr; Suski, Tadek; Marona, Lucja; Leszczyński, Mike; Wisniewski, Przemek; Czernecki, Robert; Kucharski, Robert; Targowski, Grzegorz; Watson, Malcolm A.; White, Henry; Watson, Scott; Kelly, Antony E.
2016-02-01
AlGaInN ridge waveguide laser diodes are fabricated to achieve single-mode operation with optical powers up to 100 mW at ˜420 nm for visible free-space, underwater, and plastic optical fiber communication. We report high-frequency operation of AlGaInN laser diodes with data transmission up to 2.5 GHz for free-space and underwater communication and up to 1.38 GHz through 10 m of plastic optical fiber.
Fiber-Optic Terahertz Data-Communication Networks
NASA Technical Reports Server (NTRS)
Chua, Peter L.; Lambert, James L.; Morookian, John M.; Bergman, Larry A.
1994-01-01
Network protocols implemented in optical domain. Fiber-optic data-communication networks utilize fully available bandwidth of single-mode optical fibers. Two key features of method: use of subpicosecond laser pulses as carrier signals and spectral phase modulation of pulses for optical implementation of code-division multiple access as multiplexing network protocol. Local-area network designed according to concept offers full crossbar functionality, security of data in transit through network, and capacity about 100 times that of typical fiber-optic local-area network in current use.
Sex Differences in Technical Communication: A Perspective from Social Role Theory
ERIC Educational Resources Information Center
Thompson, Isabelle
2004-01-01
This article interprets technical communication research about sex differences according to social role theory, which argues that sex differences are enculturated through experiences associated with social positions in the family and the workplace. It reevaluates technical communication research about sex differences in communicative and…
Preface to the special issue on ;Optical Communications Exploiting the Space Domain;
NASA Astrophysics Data System (ADS)
Wang, Jian; Yu, Siyuan; Li, Guifang
2018-02-01
The demand for high capacity optical communications will continue to be driven by the exponential growth of global internet traffic. Optical communications are about the exploitation of different physical dimensions of light waves, including complex amplitude, frequency (or wavelength), time, polarization, etc. Conventional techniques such as wavelength-division multiplexing (WDM), time-division multiplexing (TDM) and polarization-division multiplexing (PDM) have almost reached their scalability limits. Space domain is the only known physical dimension left and space-division multiplexing (SDM) seems the only option to further scale the transmission capacity and spectral efficiency of optical communications. In recent years, few-mode fiber (FMF), multi-mode fiber (MMF), multi-core fiber (MCF) and few-mode multi-core fiber (FM-MCF) have been widely explored as promising candidates for fiber-based SDM. The challenges for SDM include efficient (de)multiplexer, amplifiers, and multiple-input multiple-output (MIMO) digital signal processing (DSP) techniques. Photonic integration will also be a key technology to SDM. Meanwhile, free-space and underwater optical communications have also exploited the space domain to increase the transmission capacity and spectral efficiency. The challenges include long-distance transmission limited by propagation loss, divergence, scattering and turbulence. Very recently, helically phased light beams carrying orbital angular momentum (OAM) have also seen potential applications both in free-space, underwater and fiber-based optical communications. Actually, different mode bases such as linearly polarized (LP) modes and OAM modes can be employed for SDM. Additionally, SDM could be used in chip-scale photonic interconnects and data center optical interconnects. Quantum processing exploiting the space domain is of great interest. The information capacity limit and physical layer security in SDM optical communications systems are important issues to be addressed.
External Cavity Coherent Transmitter Modules
1990-11-01
Lasers 141 Tunability Aspects of DFB External Cavity Semiconductor Lasers Harish R. D. Sunak & Clark P. Engert Fiber Optical Communications Laboratory...Linewidth Considerations for DFB External Cavity Semiconductor Lasers Harish R. D. Sunak & Clark P. Engert Fiber Optical Communications Laboratory
The Boston Study: Analysis of a Major Metropolitan Business- and Technical-Communication Market.
ERIC Educational Resources Information Center
Buchholz, William J.
1989-01-01
Presents a year-long study of the duties, skills, and knowledge required of business- and technical-communication professionals in Boston, Massachusetts. Focuses on six categories of practice: technical communication, publishing, public relations, marketing, development, and training. Suggests that in the next decade communication practitioners…
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Glassman, Myron; Barclay, Rebecca O.; Oliu, Walter E.
1989-01-01
Data collected from an exploratory study concerned with the technical communications practices of aerospace engineers and scientists were analyzed to test the primary assumption that profit and nonprofit managers in the aerospace community have different technical communications practices. Five assumptions were established for the analysis. Profit and nonprofit managers in the aerospace community were found to have different technical communications practices for one of the five assumptions tested. It was, therefore, concluded that profit and nonprofit managers in the aerospace community do not have different technical communications practices.
Glue-free assembly of glass fiber reinforced thermoplastics using laser light
NASA Astrophysics Data System (ADS)
Binetruy, C.; Clement, S.; Deleglise, M.; Franz, C.; Knapp, W.; Oumarou, M.; Renard, J.; Roesner, A.
2011-05-01
The use of laser light for bonding of continuous fiber reinforced thermoplastic composites (CFTPC) offers new possibilities to overcome the constraints of conventional joining technologies. Laser bonding is environmentally friendly as no chemical additive or glue is necessary. Accuracy and flexibility of the laser process as well as the quality of the weld seams provide benefits which are already used in many industrial applications. Laser transmission welding has already been introduced in manufacturing of short fiber thermoplastic composites. The laser replaces hot air in tapelaying systems for pre-preg carbon fiber placement. The paper provides an overview concerning the technical basics of the joining process and outline some material inherent characteristics to be considered when using continuous glass fiber reinforced composites The technical feasibility and the mechanical characterization of laser bonded CFTPC are demonstrated. The influence of the different layer configurations on the laser interaction with the material is investigated and the dependency on the mechanical strength of the weld seem is analyzed. The results show that the laser provides an alternative joining technique and offers new perspectives to assemble structural components emerging in automotive or aeronautical manufacturing. It overcomes the environmental and technical difficulties related to existing gluing processes.
Photonics: Maintaining competitiveness in the information era
NASA Astrophysics Data System (ADS)
Photonics concerns the use of photons to work with or to replace electrons in certain communications, computer, or control applications traditionally carried out by electronics. It is a key high-technology area, well established in long-distance fiber-optic telecommunications and rapidly growing in other areas of great importance to society. This report concentrates on technical areas where the overall worldwide market for equipment approaches $400 billion per year, i.e., Telecommunications; Information processing; Optical storage and display; Optical sensors; and Policy Issues. It is essential to increase our industrial competitiveness in product development, manufacturing skills, and marketing; There must be continuing industrial effort in long-range research and innovation; The photonics industry should consider the advantages of an industry association that could help organize consortia to conduct cooperative research and address technical problems and policy issues beyond the scope of any one organization; and Government contractors who receive a percentage of sales for their independent research should devote a sizable fraction to projects with a life span of 5 to 10 years.
Sugar cane fiber geotextiles : production, evaluation, and field study : technical summary.
DOT National Transportation Integrated Search
1996-08-01
The sugar cane fiber geotexiles performed as well as the commercial products and exhibited grass propagation and slope protection equivalent to other products. Sugar cane fiber mats were superior in conformation to the slope even after heavy rains. B...
ERIC Educational Resources Information Center
Pinelli, Thomas E.; And Others
An exploratory study investigated technical communications in aeronautics by surveying aeronautical engineers and scientists. The study had five specific objectives: to solicit the opinions of aeronautical engineers and scientists regarding the importance of technical communications to their profession; to determine their use and production of…
Trainees' perceptions of practitioner competence during patient transfer.
Grierson, Lawrence; Dubrowski, Adam; So, Steph; Kistner, Nicole; Carnahan, Heather
2012-01-01
Technical and communicative skills are both important features for one's perception of practitioner competence. This research examines how trainees' perceptions of practitioner competence change as they view health care practitioners who vary in their technical and communicative skill proficiencies. Occupational therapy students watched standardized encounters of a practitioner performing a patient transfer in combinations of low and high technical and communicative proficiency and then reported their perceptions of practitioner competence. The reports indicate that technical and communicative skills have independently identifiable impacts on the perceptions of practitioner competency, but technical proficiency has a special impact on the students' perceptions of practitioner communicative competence. The results are discussed with respect to the way in which students may evaluate their own competence on the basis of either technical or communicative skill. The issue of how this may lead trainees to dedicate their independent learning efforts to an incomplete set of features needed for the development of practitioner competency is raised.
Package for integrated optic circuit and method
Kravitz, Stanley H.; Hadley, G. Ronald; Warren, Mial E.; Carson, Richard F.; Armendariz, Marcelino G.
1998-01-01
A structure and method for packaging an integrated optic circuit. The package comprises a first wall having a plurality of microlenses formed therein to establish channels of optical communication with an integrated optic circuit within the package. A first registration pattern is provided on an inside surface of one of the walls of the package for alignment and attachment of the integrated optic circuit. The package in one embodiment may further comprise a fiber holder for aligning and attaching a plurality of optical fibers to the package and extending the channels of optical communication to the fibers outside the package. In another embodiment, a fiber holder may be used to hold the fibers and align the fibers to the package. The fiber holder may be detachably connected to the package.
Package for integrated optic circuit and method
Kravitz, S.H.; Hadley, G.R.; Warren, M.E.; Carson, R.F.; Armendariz, M.G.
1998-08-04
A structure and method are disclosed for packaging an integrated optic circuit. The package comprises a first wall having a plurality of microlenses formed therein to establish channels of optical communication with an integrated optic circuit within the package. A first registration pattern is provided on an inside surface of one of the walls of the package for alignment and attachment of the integrated optic circuit. The package in one embodiment may further comprise a fiber holder for aligning and attaching a plurality of optical fibers to the package and extending the channels of optical communication to the fibers outside the package. In another embodiment, a fiber holder may be used to hold the fibers and align the fibers to the package. The fiber holder may be detachably connected to the package. 6 figs.
ERIC Educational Resources Information Center
Haselkorn, Mark P.; Sauer, Geoffrey; Turns, Jennifer; Illman, Deborah L.; Tsutsui, Michio; Plumb, Carolyn; Williams, Tom; Kolko, Beth; Spyridakis, Jan
2003-01-01
Presents eight current projects involving faculty in the University of Washington's Department of Technical Communication that illustrate the broadening of the field. Notes these projects address: the cognitive processing of visual material; Web-based education; strategic management of information; communicating science and technology in the…
NASA Technical Reports Server (NTRS)
Flammia, Madelyn; Barclay, Rebecca O.; Pinelli, Thomas E.; Keene, Michael L.; Burger, Robert H.; Kennedy, John M.
1993-01-01
Until the recent dissolution of the Soviet Union, the Communist Party exerted a strict control of access to and dissemination of scientific and technical information (STI). This article presents models of the Soviet-style information society and the Western-style information society and discusses the effects of centralized governmental control of information on Russian technical communication practices. The effects of political control on technical communication are then used to interpret the results of a survey of Russian and U.S. aerospace engineers and scientists concerning the time devoted to technical communication, their collaborative writing practices and their attitudes toward collaboration, the kinds of technical documents they produce and use, their views regarding the appropriate content for an undergraduate technical communication course, and their use of computer technology. Finally, the implications of these findings for future collaboration between Russian and U.S. engineers and scientists are examined.
NASA Technical Reports Server (NTRS)
Flammia, Madelyn; Barclay, Rebecca O.; Pinelli, Thomas E.; Keene, Michael L.; Burger, Robert H.; Kennedy, John M.
1993-01-01
Until the recent dissolution of the Soviet Union, the Communist Party exerted a strict control of access to and dissemination of scientific and technical information. This article presents models of the Soviet-style information society and the Western-style information society and discusses the effects of centralized governmental control of information on Russian technical communication practices. The effects of political control on technical communication are then used to interpret the results of a survey of Russian and U.S. aerospace engineers and scientists concerning the time devoted to technical communication, their collaborative writing practices and their attitudes toward collaboration, the kinds of technical documents they produce and use, their views regarding the appropriate content for an undergraduate technical communication course, and their use of computer technology. Finally, the implications of these findings for future collaboration between Russian and U.S. engineers and scientists are examined.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Glassman, Myron; Barclay, Rebecca O.; Oliu, Walter E.
1989-01-01
Data collected from an exploratory study concerned with the technical communications practices of aerospace engineers and scientists were analyzed to test the primary assumption that aerospace managers and nonmanagers have different technical communications practices. Five assumptions were established for the analysis. Aerospace managers and nonmanagers were found to have different technical communications practices for three of the five assumptions tested. Although aerospace managers and nonmanagers were found to have different technical communications practices, the evidence was neither conclusive nor compelling that the presumption of difference in practices could be attributed to the duties performed by aerospace managers and nonmanagers.
ERIC Educational Resources Information Center
Pinelli, Thomas E.; And Others
Data collected from an exploratory study concerned with the technical communications practices of aerospace engineers and scientists were analyzed to test the primary assumption that aerospace managers and nonmanagers have different technical communications practices. Five secondary assumptions were established for the analysis: (1) that the…
Integrated Photonic Orbital Angular Momentum Multiplexing and Demultiplexing on Chip
2014-10-31
OAM free space coherent communication link testbed. ECL: external cavity laser . EDFA: erbium-doped fiber amplifier. PC: polarization controller. ATT...wave (cw) laser centered at 1540 nm, followed by an erbium-doped fiber amplifier (EDFA), an I/Q modulator, and another EDFA. The I/Q modulator was...communication link testbed. ECL: external cavity laser . EDFA: erbium-doped fiber amplifier. PC: polarization controller. ATT: attenuator. BPF: bandpass filter
EDI and the Technical Communicator.
ERIC Educational Resources Information Center
Eiler, Mary Ann
1994-01-01
Assesses the role of technical communicators in electronic data interchange (EDI). Argues that, as experts in information design, human factors, instructional theory, and professional writing, technical communicators should be advocates of standard documentation protocols and should rethink the traditional concepts of "document" to…
The Impact of Language and Culture on Technical Communication in Japan.
ERIC Educational Resources Information Center
Kohl, John R.; And Others
1993-01-01
Analyzes ambiguity as a factor in Japanese language and culture as they affect technical communication. Presents and interprets results of a survey of Japanese and U.S. aerospace engineers and scientists concerning the kinds of communication products they produce and use and their ideas of what should be taught in technical communication courses.…
ERIC Educational Resources Information Center
Pinelli, Thomas E.; Sato, Yuko; Barclay, Rebecca O.; Kennedy, John M.
1997-01-01
Japanese (n=94) and U.S. (n=340) aerospace scientists/engineers described time spent communicating information, collaborative writing, importance of technical communication courses, and the use of libraries, computer networks, and technical reports. Japanese respondents had greater language fluency; U.S. respondents spent more time with…
Hollow fiber apparatus and use thereof for fluids separations and heat and mass transfers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bikson, Benjamin; Etter, Stephen; Ching, Nathaniel
A hollow fiber fluid separation device includes a hollow fiber cartridge, comprising a plurality of hollow fiber membranes arranged around a central tubular core, a first tubesheet and a second tubesheet encapsulating respective distal ends of the hollow fiber bundle. The tubesheets have boreholes in fluid communication with bores of the hollow fiber membrane. In at least one of the tubesheets, the boreholes are formed radially and are in communication with the central tubular core. The hollow fiber fluid separation device can be utilized in liquid separation applications such as ultrafiltration and in gas separation processes such as air separation.more » The design disclosed herein is light weight and compact and is particularly advantageous at high operating temperatures when the pressure of the feed fluid introduced into the bores of hollow fibers is higher than the pressure on the shell side of the device.« less
And They're Off! The Race to Fiber Optics.
ERIC Educational Resources Information Center
Lewis, Joan E.
1993-01-01
Describes fiber optic technology and discusses its use in distance learning and educational reform. Highlights include the quality of communications transmission systems; costs; Federal Communications Commission rules and regulations; cable television; networks, including the National Research and Education Network (NREN); government versus…
Describing Acupuncture: A New Challenge for Technical Communicators.
ERIC Educational Resources Information Center
Karanikas, Marianthe
1997-01-01
Considers acupuncture as an increasingly popular alternative medical therapy, but difficult to describe in technical communication. Notes that traditional Chinese medical explanations of acupuncture are unscientific, and that scientific explanations of acupuncture are inconclusive. Finds that technical communicators must translate acupuncture for…
ERIC Educational Resources Information Center
Pinelli, Thomas E.; And Others
Data collected from an exploratory study concerned with the technical communications practices of aerospace engineers and scientists were analyzed to test the primary assumption that profit and nonprofit managers in the aerospace community have different technical communications practices. Profit and nonprofit managers were compared in five…
Oral Communication and Technical Writing: A Reconsideration of Writing in a Multicultural Era
ERIC Educational Resources Information Center
Cibangu, Sylvain K.
2009-01-01
This article investigates the status of orality in the history of technical communication. The article calls for orality as an integral part and driving force of technical writing. The article brings to light the misconceptions that have led to a diminished role of oral communication in technical writing. The article shows the implications of oral…
NASA Astrophysics Data System (ADS)
Lu, Ping
The thesis consists of two research directions: Optical fiber applications in gas concentration and radiation dose measurements; and polarization effects in fiber optic communication systems. Part I of the thesis presents two optical fiber applications. (1) An infrared (IR) fiber bundle has been designed and fabricated to measure gas concentrations in a chemical vapor deposition (CVD) chamber using Fourier transform infrared spectroscopy. This fiber bundle covers the IR range from 0.5 to 20 mum and reduces the light beam divergence in the CVD chamber, which makes it possible to measure gas concentrations in a region near the substrate surface. Semi-ellipsoid mirrors have been designed and used to increase the collection efficiency of infrared radiation and to compensate the loss introduced by the fiber bundle. (2) A fiber optic radiation sensor based on radiation-induced fiber loss is reported. The gamma radiation-induced loss spectra in various fibers have been studied. Among all the fibers tested, 5% P-doped fiber shows the highest sensitivity to gamma radiation. The wavelength and dose rate dependence of radiation-induced loss in 5% P-doped fiber are investigated and the possibility of using this fiber as a radiation sensor for radiation therapy is discussed. Part II of the thesis examines two polarization effects, polarization mode dispersion (PMD) and polarization dependent loss (PDL), in fiber optic communication systems based on the waveplate models. A new waveplate model, capable of generating any PMD and PDL values, is proposed to overcome the limitations of the conventional waveplate model. Using both models the statistical distributions of PDL and differential group delay (DGD) have been studied considering the presence of biased elliptical birefringence. The principal state of polarization (PSP) of an optical pulse is proposed for a fiber having both PMD and PDL. PMD and PDL of a pulse for a fiber consisting of two polarization maintaining fiber segments are calculated, and the pulse distortions due to PMD and PDL are analyzed. PMD and PDL impact on digital communication systems have been studied in terms of system Q factor, bit error rate (BER) and system outage probability. The acceptable PMD values in a system with PDL are discussed for various power margins. The Q factor distributions due to PDL and its combination with PMD have been measured experimentally and compared to numerical simulations.
Fiber Bragg grating sensor-based communication assistance device
NASA Astrophysics Data System (ADS)
Padma, Srivani; Umesh, Sharath; Pant, Shweta; Srinivas, Talabattula; Asokan, Sundarrajan
2016-08-01
Improvements in emergency medicine in the form of efficient life supporting systems and intensive care have increased the survival rate in critically injured patients; however, in some cases, severe brain and spinal cord injuries can result in a locked-in syndrome or other forms of paralysis, and communication with these patients may become restricted or impossible. The present study proposes a noninvasive, real-time communication assistive methodology for those with restricted communication ability, employing a fiber Bragg grating (FBG) sensor. The communication assistive methodology comprises a breath pattern analyzer using an FBG sensor, which acquires the exhalation force that is converted into strain variations on a cantilever. The FBG breath pattern analyzer along with specific breath patterns, which are programmed to give specific audio output commands, constitutes the proposed fiber Bragg grating sensor-based communication assistive device. The basic communication can be carried out by instructing the patients with restricted communication ability to perform the specific breath patterns. The present approach is intended to be an alternative to the common approach of brain-computer interface in which an instrument is utilized for learning of brain responses.
NASA Technical Reports Server (NTRS)
Kennedy, John M.; Pinelli, Thomas E.; Hecht, Laura Frye; Barclay, Rebecca O.
1995-01-01
In this paper we describe the preliminary analysis of four groups of aerospace engineering and science students -- student members of the American Institute of Aeronautics and Astronautics (AIAA) and students from universities in Japan, Russia, and Great Britain. We compare: (1) the demographic characteristics of the students; (2) factors that affected their career decision; (3) their career goals and aspirations; (4) their training in technical communication; and (5) their training in techniques for finding and using aerospace scientific and technical information (STI). Many employers in the US aerospace industry think there is a need for increased training of engineering students in technical communication. Engineers in the US and other countries believe that technical communication skills are critical for engineers' professional success. All students in our study agree about the importance of technical communication training for professional success, yet relatively few are happy with the instruction they receive. Overall, we conclude that additional instruction in technical communication and accessing STI would make it easier for students to achieve their career goals.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xiao, Hai; Dong, Junhang; Lin, Jerry
2012-03-01
This is a final technical report for the first project year from July 1, 2005 to Jan 31, 2012 for DoE/NETL funded project DE-FC26-05NT42439: Development of Nanocrystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases. This report summarizes the technical progresses and achievements towards the development of novel nanocrystalline doped ceramic material-enabled optical fiber sensors for in situ and real time monitoring the gas composition of flue or hot gas streams involved in fossil-fuel based power generation and hydrogen production.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-14
... Technologies'') to amend the complaint and notice of investigation (``NOI''). FOR FURTHER INFORMATION CONTACT... Fiber Optic Communications, Components Thereof, and Products Containing Same; Commission Determination Not To Review an Initial Determination Granting Complainants Avago Technologies General IP (Singapore...
Four-Mode Squeezing For Optical Communications
NASA Technical Reports Server (NTRS)
Schumaker, Bonny L.
1989-01-01
Experiments demonstrated potential of four-mode squeezing for increasing immunity to noise in fiber-optical communication systems and interferometric devices. Four-mode squeezing reduces quantum noise more than ordinary squeezing and provides partial immunity to non-quantum-mechanical phase noise arising in such media as optical fibers.
The Unfortunate Human Factor: A Selective History of Human Factors for Technical Communicators.
ERIC Educational Resources Information Center
Johnson, Robert R.
1994-01-01
Reviews moments in the history of human factors that are especially relevant to the field of technical communications. Discusses human factors research that is applicable to technical communications. Focuses on qualitative usability research, minimalism, and human activity interface design. (HB)
Gender, Technology, and the History of Technical Communication.
ERIC Educational Resources Information Center
Durack, Katherine T.
1997-01-01
Considers why women have been absent from the history of technical communication. Discusses research from the history of technology suggesting that notions of "technology,""work," and "workplace" may be gendered terms. Concludes with several suggestions for defining technical communication so that significant works of…
Innovative Approaches to Teaching Technical Communication
ERIC Educational Resources Information Center
Bridgeford, Tracy, Ed.; Kitalong, Karla Saari, Ed.; Selfe, Dickie, Ed.
2004-01-01
"Innovative Approaches to Teaching Technical Communication" offers a variety of activities, projects, and approaches to energize pedagogy in technical communication and to provide a constructive critique of current practice. A practical collection, the approaches recommended here are readily adaptable to a range of technological and institutional…
ERIC Educational Resources Information Center
Warren, Thomas, Ed.
Articles in these proceedings of a conference of the Council for Programs in Technical and Scientific Communication represent the views of professional communicators and academicians who share a concern for providing breadth and quality of preparation of present and future technical communicators. The 11 articles discuss the following topics: (1)…
Installing the Future. Fiber Optics Program Readies Students for Lucrative Jobs.
ERIC Educational Resources Information Center
Serrano, Kenneth M.
1995-01-01
A fiber optics program at Somerset County Technical Institute (SCTI) prepares college students and trades workers for telecommunication's new wave of installation. The program was born of a partnership among an electricians' union, AT&T, and SCTI to meet the expected need for fiber optic technicians. (JOW)
47 CFR 51.323 - Standards for physical collocation and virtual collocation.
Code of Federal Regulations, 2011 CFR
2011-10-01
... accessible by both the incumbent LEC and the collocating telecommunications carrier, at which the fiber optic... technically feasible, the incumbent LEC shall provide the connection using copper, dark fiber, lit fiber, or... that the incumbent LEC may adopt include: (1) Installing security cameras or other monitoring systems...
47 CFR 51.323 - Standards for physical collocation and virtual collocation.
Code of Federal Regulations, 2010 CFR
2010-10-01
... accessible by both the incumbent LEC and the collocating telecommunications carrier, at which the fiber optic... technically feasible, the incumbent LEC shall provide the connection using copper, dark fiber, lit fiber, or... that the incumbent LEC may adopt include: (1) Installing security cameras or other monitoring systems...
1986-05-01
Composites Using Ultrasonic Nondestructive Evaluation Annual Technical Report I by Vikrai K. Kinra Depdrtment of Aerospace Engineering r and Mechanics...and identify by b ko number) 7It is well known that composite materials suffer complex damage when they are.-ub- jected to either monotonic or...Characterization of Damage States in Continuous Fiber Composites Using Ultrasonic Nondestructive Evaluation Annual Technical Report by Vikram K. Kinra Department
Optical data communication: fundamentals and future directions
NASA Astrophysics Data System (ADS)
DeCusatis, Casimer M.
1998-12-01
An overview of optical data communications is provided, beginning with a brief history and discussion of the unique requirements that distinguish this subfield from related areas such as telecommunications. Each of the major datacom standards is then discussed, including the physical layer specification, distances and data rates, fiber and connector types, data frame structures, and network considerations. These standards can be categorized by their prevailing applications, either storage [Enterprise System Connection, Fiber Channel Connection, and Fiber Channel], coupling (Fiber Channel), or networking [Fiber Distributed Data Interface, Gigabit Ethernet, and asynchronous transfer mode/synchronous optical network]. We also present some emerging technologies and their applications, including parallel optical interconnects, plastic optical fiber, wavelength multiplexing, and free- space optical links. We conclude with some cost/performance trade-offs and predictions of future bandwidth trends.
The Golden Age of Technical Communication
ERIC Educational Resources Information Center
Kimball, Miles A.
2017-01-01
This article uses a historical perspective to describe the development of the profession of technical communication through three ages: Brass, Beige, and Glass. I compare this development to the growth of the academic discipline and both to the explosion of noninstitutional technical communication--the growing body of tactical technical…
Going Online: Helping Technical Communicators Help Translators.
ERIC Educational Resources Information Center
Flint, Patricia; Lord van Slyke, Melanie; Starke-Meyerring, Doreen; Thompson, Aimee
1999-01-01
Explains why technical communicators should help translators. Offers tips for creating "translation-friendly" documentation. Describes the research and design process used by the authors to create an online tutorial that provides technical communicators at a medical technology company the information they need to help them write and…
Quantum information processing with a travelling wave of light
NASA Astrophysics Data System (ADS)
Serikawa, Takahiro; Shiozawa, Yu; Ogawa, Hisashi; Takanashi, Naoto; Takeda, Shuntaro; Yoshikawa, Jun-ichi; Furusawa, Akira
2018-02-01
We exploit quantum information processing on a traveling wave of light, expecting emancipation from thermal noise, easy coupling to fiber communication, and potentially high operation speed. Although optical memories are technically challenging, we have an alternative approach to apply multi-step operations on traveling light, that is, continuous-variable one-way computation. So far our achievement includes generation of a one-million-mode entangled chain in time-domain, mode engineering of nonlinear resource states, and real-time nonlinear feedforward. Although they are implemented with free space optics, we are also investigating photonic integration and performed quantum teleportation with a passive liner waveguide chip as a demonstration of entangling, measurement, and feedforward. We also suggest a loop-based architecture as another model of continuous-variable computing.
NASA Technical Reports Server (NTRS)
Frazier, Donald O.
2000-01-01
Technically, the field of integrated optics using organic/polymer materials as a new means of information processing, has emerged as of vital importance to optical computers, optical switching, optical communications, the defense industry, etc. The goal is to replace conventional electronic integrated circuits and wires by equivalent miniaturized optical integrated circuits and fibers, offering larger bandwidths, more compactness and reliability, immunity to electromagnetic interference and less cost. From the Code E perspective, this research area represents an opportunity to marry "front-line" education in science and technology with national scientific and technological interests while maximizing human resources utilization. This can be achieved by the development of untapped resources for scientific research - such as minorities, women, and universities traditionally uninvolved in scientific research.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-20
... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-860] Certain Optoelectronic Devices for Fiber Optic Communications, Components Thereof, and Products Containing the Same; Notice of Request for Statements on the Public Interest AGENCY: U.S. International Trade Commission. ACTION: Notice. SUMMARY...
A Fibre-Optic Communications Network for Teaching Clinical Medicine.
ERIC Educational Resources Information Center
Williams, Robin
1985-01-01
Describes an interactive television system based on fiber-optic communications technology which is used to facilitate participation by University of London medical students in lecture/tutorials by teachers in different hospital locations. Highlights include advantages of fiber-optics, cable manufacture and installation, opto-electronic interface,…
Dissemination, redissemination and fiber life
NASA Technical Reports Server (NTRS)
Eiber, W.
1979-01-01
The technical background of dissemination of carbon fibers as well as the possibility of redissemination and fiber life are outlined. Plume spread and weather, measures of pollution and of damage potential, and parameters controlling dissemination patterns are among the topics discussed. It is shown that the redissemination rate off hard surfaces decreases with time and that fiber length decreases with time. Redissemination from vegetated land is shown to be insignificant.
Postselection-Loophole-Free Bell Test Over an Installed Optical Fiber Network.
Carvacho, Gonzalo; Cariñe, Jaime; Saavedra, Gabriel; Cuevas, Álvaro; Fuenzalida, Jorge; Toledo, Felipe; Figueroa, Miguel; Cabello, Adán; Larsson, Jan-Åke; Mataloni, Paolo; Lima, Gustavo; Xavier, Guilherme B
2015-07-17
Device-independent quantum communication will require a loophole-free violation of Bell inequalities. In typical scenarios where line of sight between the communicating parties is not available, it is convenient to use energy-time entangled photons due to intrinsic robustness while propagating over optical fibers. Here we show an energy-time Clauser-Horne-Shimony-Holt Bell inequality violation with two parties separated by 3.7 km over the deployed optical fiber network belonging to the University of Concepción in Chile. Remarkably, this is the first Bell violation with spatially separated parties that is free of the postselection loophole, which affected all previous in-field long-distance energy-time experiments. Our work takes a further step towards a fiber-based loophole-free Bell test, which is highly desired for secure quantum communication due to the widespread existing telecommunication infrastructure.
Postselection-Loophole-Free Bell Test Over an Installed Optical Fiber Network
NASA Astrophysics Data System (ADS)
Carvacho, Gonzalo; Cariñe, Jaime; Saavedra, Gabriel; Cuevas, Álvaro; Fuenzalida, Jorge; Toledo, Felipe; Figueroa, Miguel; Cabello, Adán; Larsson, Jan-Åke; Mataloni, Paolo; Lima, Gustavo; Xavier, Guilherme B.
2015-07-01
Device-independent quantum communication will require a loophole-free violation of Bell inequalities. In typical scenarios where line of sight between the communicating parties is not available, it is convenient to use energy-time entangled photons due to intrinsic robustness while propagating over optical fibers. Here we show an energy-time Clauser-Horne-Shimony-Holt Bell inequality violation with two parties separated by 3.7 km over the deployed optical fiber network belonging to the University of Concepción in Chile. Remarkably, this is the first Bell violation with spatially separated parties that is free of the postselection loophole, which affected all previous in-field long-distance energy-time experiments. Our work takes a further step towards a fiber-based loophole-free Bell test, which is highly desired for secure quantum communication due to the widespread existing telecommunication infrastructure.
How Do We Teach Usability? An Investigation of Usability Instruction in Technical Communication
ERIC Educational Resources Information Center
Chong, Felicia
2013-01-01
This dissertation investigates the curricular implementation of usability instruction in technical communication. Though there are a plethora of publications and studies on usability in technical communication, little discussion focuses on usability instruction in the classroom or its implementation in the curriculum. Thus, this exploratory…
Evaluating Technical Communication Faculty: Some Empirically-Based Criteria and Guidelines. Draft.
ERIC Educational Resources Information Center
Stevenson, Dwight W.
As technical communication is a young academic discipline, evaluating technical communication faculty for promotion, tenure, and merit purposes requires special awareness and care. To determine reasonable expectations of faculty achievement, a study documented the range, types, and frequency of activities of 12 professors and 12 associate…
Moving International Technical Communication Forward: A World Englishes Approach
ERIC Educational Resources Information Center
Bokor, Michael Jarvis Kwadzo
2011-01-01
This article explores how the English language contributes to cross-boundary communication failure and establishes that there is an "English language problem" that has not been adequately addressed in preparing United States native English-speaking students for international technical communication tasks. For example, U.S. technical communication…
My Career and the "Rhetoric of" Technical Writing and Communication
ERIC Educational Resources Information Center
Schuster, Mary Lay
2015-01-01
This article traces the history of Mary Schuster's career in technical writing and communication from 1968 when she took a position in the Publications Department at the Institute of Electrical and Electronics Engineers (IEEE) to her work at "Technical Communication Quarterly" ("TCQ") in 2003 and forward. She discusses the…
Technical Communication in the 21st Century: Where Are We Going?
ERIC Educational Resources Information Center
Killingsworth, M. Jimmie
1999-01-01
Explores how technical communicators arrive at their attitudes toward the future and the effects of such attitudes toward current practice. Argues for a critically informed, open-minded approach to the future, an approach that encourages an honest self-criticism within the discipline of technical communication. (SC)
The Technical Communicator as Corporate Spokesperson: A Public Relations Primer.
ERIC Educational Resources Information Center
Troester, Rod; Warburton, Terrence L.
2001-01-01
Examines the changing role of the technical communication professional in the rapidly evolving environment of organizational life. Presents five principles that serve as an initial step in laying a foundation for the preparation of technical communicators for the challenges and opportunities awaiting in contemporary organizations and the…
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.; Glassman, Myron
1990-01-01
Two pilot studies were conducted that investigated the technical communications practices of U.S. and European aerospace engineers and scientists. Both studies had the same five objectives: (1) solicit opinions regarding the importance of technical communications; (2) determine the use and production of technical communications; (3) seek views about the appropriate content of an undergraduate course in technical communications; (4) determine use of libraries, information centers, and online database; (5) determine use and importance of computer and information technology to them. A self-administered questionnaire was mailed to randomly selected aerospace engineers and scientists, with a slightly modified version sent to European colleagues. Their responses to selected questions are presented in this paper.
Helping Students to Prepare a Technical Communications Portfolio.
ERIC Educational Resources Information Center
Ware, Elaine
1988-01-01
Stresses the importance of teaching prospective technical writers to develop, organize, and present a technical communications portfolio. Provides a checklist on portfolio construction for students. (ARH)
ERIC Educational Resources Information Center
Miller, Greg; Doerfert, David L.
The purpose of this descriptive study was to investigate the usefulness of an interactive communications network for agricultural education at the secondary level. The Iowa Communications Network (ICN) is a two-way full motion fiber optics telecommunications system capable of linking secondary agricultural departments throughout Iowa. The…
Optical Intrabuilding and Interbuilding Distribution Networks.
ERIC Educational Resources Information Center
Hull, Joseph A.
Fiber optics communication technology is a potential competitive alternative to coaxial cable and shielded twisted pairlines as a wide-band communications medium. Pilot demonstrations by public institutions such as the health care delivery system can test the application of this new technology. Fiber optic networks may have the potential to be…
DOT National Transportation Integrated Search
2004-07-01
The objectives of this study were to evaluate the effects of soil density, moisture content, fiber content, and confining pressure on the shear strength of the clayey-fiber matrix, and of soil moisture content and confining pressure on the interface ...
Eddy-Current Inspection Of Graphite-Fiber Composites
NASA Technical Reports Server (NTRS)
Workman, G. L.; Bryson, C. C.
1993-01-01
NASA technical memorandum describes initial research on, and proposed development of, automated system for nondestructive eddy-current inspection of parts made of graphite-fiber/epoxy-matrix composite materials. Sensors in system E-shaped or U-shaped eddy-current probes like those described in "Eddy-Current Probes For Inspecting Graphite-Fiber Composites" (MFS-26129).
Piloting a fiber optics and electronic theory curriculum with high school students
NASA Astrophysics Data System (ADS)
Gilchrist, Pamela O.; Carpenter, Eric D.; Gray-Battle, Asia
2014-07-01
Previous participants from a multi-year blended learning intervention focusing on science, technology, engineering and mathematics (STEM) content knowledge, technical, college, and career preparatory skills were recruited to pilot a new module designed by the project staff. Participants met for a total of 22 contact hours receiving lectures from staff and two guest speakers from industries relevant to photonics, fiber optics hands-on experimentation, and practice with documenting progress. Activities included constructing a fiber optics communication system, troubleshooting breadboard circuits and diagrammed circuits as well as hypothesis testing to discover various aspects of fiber optic cables. Participants documented their activities, wrote reflections on the content and learning endeavor and gave talks about their research experiences to staff, peers, and relatives during the last session. Overall, it was found that a significant gain in content knowledge occurred between the time of pre-testing (Mean=0.54) and post-testing time points for the fiber optics portion of the curriculum via the use of a paired samples t-test (Mean=0.71), t=-2.72, p<.05. Additionally, the electronic theory test results were not a normal distribution and for this reason non-parametric testing was used, specifically a Wilcoxon signed-ranks test. Results indicated a significant increase in content knowledge occurred over time between the pre- (Mdn=0.35) and post-testing time points (Mdn=0.80) z=-2.49, p<,05, r=-0.59 for the electronic theory portion of the curriculum. An equivalent control group was recruited from the remaining participant pool, allowing for comparison between groups. The program design, findings, and lessons learned will be reported in this paper.
UNC-Utah NA-MIC framework for DTI fiber tract analysis.
Verde, Audrey R; Budin, Francois; Berger, Jean-Baptiste; Gupta, Aditya; Farzinfar, Mahshid; Kaiser, Adrien; Ahn, Mihye; Johnson, Hans; Matsui, Joy; Hazlett, Heather C; Sharma, Anuja; Goodlett, Casey; Shi, Yundi; Gouttard, Sylvain; Vachet, Clement; Piven, Joseph; Zhu, Hongtu; Gerig, Guido; Styner, Martin
2014-01-01
Diffusion tensor imaging has become an important modality in the field of neuroimaging to capture changes in micro-organization and to assess white matter integrity or development. While there exists a number of tractography toolsets, these usually lack tools for preprocessing or to analyze diffusion properties along the fiber tracts. Currently, the field is in critical need of a coherent end-to-end toolset for performing an along-fiber tract analysis, accessible to non-technical neuroimaging researchers. The UNC-Utah NA-MIC DTI framework represents a coherent, open source, end-to-end toolset for atlas fiber tract based DTI analysis encompassing DICOM data conversion, quality control, atlas building, fiber tractography, fiber parameterization, and statistical analysis of diffusion properties. Most steps utilize graphical user interfaces (GUI) to simplify interaction and provide an extensive DTI analysis framework for non-technical researchers/investigators. We illustrate the use of our framework on a small sample, cross sectional neuroimaging study of eight healthy 1-year-old children from the Infant Brain Imaging Study (IBIS) Network. In this limited test study, we illustrate the power of our method by quantifying the diffusion properties at 1 year of age on the genu and splenium fiber tracts.
UNC-Utah NA-MIC framework for DTI fiber tract analysis
Verde, Audrey R.; Budin, Francois; Berger, Jean-Baptiste; Gupta, Aditya; Farzinfar, Mahshid; Kaiser, Adrien; Ahn, Mihye; Johnson, Hans; Matsui, Joy; Hazlett, Heather C.; Sharma, Anuja; Goodlett, Casey; Shi, Yundi; Gouttard, Sylvain; Vachet, Clement; Piven, Joseph; Zhu, Hongtu; Gerig, Guido; Styner, Martin
2014-01-01
Diffusion tensor imaging has become an important modality in the field of neuroimaging to capture changes in micro-organization and to assess white matter integrity or development. While there exists a number of tractography toolsets, these usually lack tools for preprocessing or to analyze diffusion properties along the fiber tracts. Currently, the field is in critical need of a coherent end-to-end toolset for performing an along-fiber tract analysis, accessible to non-technical neuroimaging researchers. The UNC-Utah NA-MIC DTI framework represents a coherent, open source, end-to-end toolset for atlas fiber tract based DTI analysis encompassing DICOM data conversion, quality control, atlas building, fiber tractography, fiber parameterization, and statistical analysis of diffusion properties. Most steps utilize graphical user interfaces (GUI) to simplify interaction and provide an extensive DTI analysis framework for non-technical researchers/investigators. We illustrate the use of our framework on a small sample, cross sectional neuroimaging study of eight healthy 1-year-old children from the Infant Brain Imaging Study (IBIS) Network. In this limited test study, we illustrate the power of our method by quantifying the diffusion properties at 1 year of age on the genu and splenium fiber tracts. PMID:24409141
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.; Glassman, Myron
1990-01-01
The flow of scientific and technical information (STI) at the individual, organizational, national, and international levels is studied. The responses of U.S and European aerospace engineers and scientists to questionnaires concerning technical communications in aerospace are examined. Particular attention is given to the means used to communicate information and the social system of the aerospace knowledge diffusion process. Demographic data about the survey respondents are provided. The methods used to communicate technical data and the sources utilized to solve technical problems are described. The importance of technical writing skills and the use of computer technology in the aerospace field are discussed. The derived data are useful for R&D and information managers in order to improve access to and utilization of aerospace STI.
Shedding Light on Fiber Optics.
ERIC Educational Resources Information Center
Bunch, Robert M.
1994-01-01
Explains the principles of fiber optics as a medium for light-wave communication. Current uses of fiber systems on college campuses include voice, video, and local area network applications. A group of seven school districts in Minnesota are linked via fiber-optic cables. Other uses are discussed. (MLF)
Using case studies to teach an engineering technology technical writing class
NASA Technical Reports Server (NTRS)
Green, M. M.
1981-01-01
The use of the case method in teaching various technical communication skills is described. Features of the method considered include: solving communication problems, identifying an audience, planning written communications, presenting written communications, and using visual aids.
Editing in Technical Communication: Theory and Practice in Editing Processes at the Graduate Level.
ERIC Educational Resources Information Center
Masse, Roger E.
At New Mexico State University, technical communication teachers have developed a course to teach editing processes to graduate students who take the advanced workshop in technical and professional communication. In this seminar group, students work on writing processes; editing processes; written, edited, and tested products; and oral processes…
ERIC Educational Resources Information Center
Schafer, Robert
2009-01-01
A significant problem for practitioners of technical communication is to gain the skills to compete in a global, multicultural work environment. Instructors of technical communication can provide future practitioners with the tools to compete and excel in this global environment by introducing heuristics of cultural dimensions into the…
Rethinking Technical Communication Pedagogy: A Poststructuralist View of Program and Course Design.
ERIC Educational Resources Information Center
Woolever, Kristin R.
Technical communication specialists today really have to be technology experts as well as effective writers--even their titles have changed to "information designers, information engineers, or document developers." Teachers of technical communication should be up to date in the classroom to meet the changing needs of the workplace.…
A Basic Unit on Ethics for Technical Communicators.
ERIC Educational Resources Information Center
Markel, Mike
1991-01-01
Describes a basic unit on ethics for technical communicators and offers suggestions on how to go about teaching the unit. Includes a brief definition of ethics, an explanation of the employee's three basic obligations, ways to analyze common dilemmas in technical communication, the role of the code of conduct, and a case study. (SR)
ERIC Educational Resources Information Center
Singleton, Meredith
2016-01-01
This dissertation study seeks to determine whether feedback in the online Technical and Professional Communication classroom impacts student performance. This dissertation proposes that online Technical and Professional Communication instructors consider adopt such a feedback methodology in order to engage students with writing practices that…
Technical Communicator: A New Model for the Electronic Resources Librarian?
ERIC Educational Resources Information Center
Hulseberg, Anna
2016-01-01
This article explores whether technical communicator is a useful model for electronic resources (ER) librarians. The fields of ER librarianship and technical communication (TC) originated and continue to develop in relation to evolving technologies. A review of the literature reveals four common themes for ER librarianship and TC. While the…
ERIC Educational Resources Information Center
Savage, Gerald J.; Seible, Marcea K.
2010-01-01
This article reports a study of internship requirements in technical communication programs compared with three established professions and one emerging profession that have certification or licensing requirements for practitioners. The study addresses three questions about technical communication internship programs: 1) Are internships offered as…
Evaluation of Glass Fiber Reinforced Concrete Panels for Use in Military Construction.
1984-06-01
AD-A158 134 UNCLASSIFIED EVALUATION OF GLASS FIBER REINFORCED CONCRETE PANELS FOR USE IN MILITARY. . (U) CONSTRUCTION ENGINEERING RESEARCH LAB...Construction Engineering Research Laboratory i=h-C=iU. TECHNICAL REPORT M-85/15 June 1985 AD-A158 134 0~- 8 Evaluation of Glass Fiber ...Reinforced Concrete Panels for Use in Military Construction by Gilbert R. Williamson Glass fiber reinforced concrete (GFRC) materials are investigated
NASA Astrophysics Data System (ADS)
Waki, Masaki; Uruno, Shigenori; Ohashi, Hiroyuki; Manabe, Tetsuya; Azuma, Yuji
We propose an optical fiber connection navigation system that uses visible light communication for an integrated distribution module in a central office. The system realizes an accurate database, requires less skilled work to operate and eliminates human error. This system can achieve a working time reduction of up to 88.0% compared with the conventional work without human error for the connection/removal of optical fiber cords, and is economical as regards installation and operation.
Superdense Coding over Optical Fiber Links with Complete Bell-State Measurements
NASA Astrophysics Data System (ADS)
Williams, Brian P.; Sadlier, Ronald J.; Humble, Travis S.
2017-02-01
Adopting quantum communication to modern networking requires transmitting quantum information through a fiber-based infrastructure. We report the first demonstration of superdense coding over optical fiber links, taking advantage of a complete Bell-state measurement enabled by time-polarization hyperentanglement, linear optics, and common single-photon detectors. We demonstrate the highest single-qubit channel capacity to date utilizing linear optics, 1.665 ±0.018 , and we provide a full experimental implementation of a hybrid, quantum-classical communication protocol for image transfer.
Mechanical Properties of Heat-treated Carbon Fibers
NASA Technical Reports Server (NTRS)
Effinger, Michael R.; Patel, Bhavesh; Koenig, John; Cuneo, Jaques; Neveux, Michael G.; Demos, Chrystoph G.
2004-01-01
Carbon fibers are selected for ceramic matrix composites (CMC) are based on their as-fabricated properties or on "that is what we have always done" technical culture while citing cost and availability when there are others with similar cost and availability. However, the information is not available for proper selection of carbon fibers since heat-treated properties are not known for the fibers on the market currently. Heat-treating changes the fiber's properties. Therefore, an effort was undertaken to establish fiber properties on 19 different types of fibers from six different manufactures for both PAN and pitch fibers. Heat-treating has been done at three different temperatures.
Fiber-based free-space optical coherent receiver with vibration compensation mechanism.
Zhang, Ruochi; Wang, Jianmin; Zhao, Guang; Lv, Junyi
2013-07-29
We propose a novel fiber-based free-space optical (FSO) coherent receiver for inter-satellite communication. The receiver takes advantage of established fiber-optic components and utilizes the fine-pointing subsystem installed in FSO terminals to minimize the influence of satellite platform vibrations. The received beam is coupled to a single-mode fiber, and the coupling efficiency of the system is investigated both analytically and experimentally. A receiving sensitivity of -38 dBm is obtained at the forward error correction limit with a transmission rate of 22.4 Gbit/s. The proposed receiver is shown to be a promising component for inter-satellite optical communication.
Communications Via Undersea Cables: Present And Future
NASA Astrophysics Data System (ADS)
Paul, D. K.
1985-11-01
Advances in fiber optic technology in the past few years have firmly established the superiority of optical fiber to coaxial cables, particularly for large-capacity, long-haul transmission systems. Recently, several undersea fiber optic cable systems have been proposed by both common and noncommon carriers. This paper addresses the techno-economic implications of these applications, and includes a brief review of the current status of undersea cable technology and a projection of future demand and capabilities. The prospects for using high-speed, multifiber undersea cable systems for international communications, extension of these systems through fiber optic terrestrial distribution, and future developmental trends are critically assessed.
1998-02-05
Sections of ZBLAN fibers pulled in a conventional 1-g process (left) and in experiments aboard NASA's KC-135 low-gravity aircraft. The rough surface of the 1-g fiber indicates surface defects that would scatter an optical signal and greatly degrade its quality. ZBLAN is part of the family of heavy-metal fluoride glasses (fluorine combined zirconium, barium, lanthanum, aluminum, and sodium). NASA is conducting research on pulling ZBLAN fibers in the low-g environment of space to prevent crystallization that limits ZBLAN's usefulness in optical fiber-based communications. ZBLAN is a heavy-metal fluoride glass that shows exceptional promise for high-throughput communications with infrared lasers. Photo credit: NASA/Marshall Space Flight Center
Bit-error-rate testing of fiber optic data links for MMIC-based phased array antennas
NASA Technical Reports Server (NTRS)
Shalkhauser, K. A.; Kunath, R. R.; Daryoush, A. S.
1990-01-01
The measured bit-error-rate (BER) performance of a fiber optic data link to be used in satellite communications systems is presented and discussed. In the testing, the link was measured for its ability to carry high burst rate, serial-minimum shift keyed (SMSK) digital data similar to those used in actual space communications systems. The fiber optic data link, as part of a dual-segment injection-locked RF fiber optic link system, offers a means to distribute these signals to the many radiating elements of a phased array antenna. Test procedures, experimental arrangements, and test results are presented.
NASA Technical Reports Server (NTRS)
Wilson, R. Gale
1994-01-01
The potential capabilities and limitations of single ball lenses for coupling laser diode radiation to single-mode optical fibers have been analyzed; parameters important to optical communications were specifically considered. These parameters included coupling efficiency, effective numerical apertures, lens radius, lens refractive index, wavelength, magnification in imaging the laser diode on the fiber, and defocus to counterbalance spherical aberration of the lens. Limiting numerical apertures in object and image space were determined under the constraint that the lens perform to the Rayleigh criterion of 0.25-wavelength (Strehl ratio = 0.80). The spherical aberration-defocus balance to provide an optical path difference of 0.25 wavelength units was shown to define a constant coupling efficiency (i.e., 0.56). The relative numerical aperture capabilities of the ball lens were determined for a set of wavelengths and associated fiber-core diameters of particular interest for single-mode fiber-optic communication. The results support general continuing efforts in the optical fiber communications industry to improve coupling links within such systems with emphasis on manufacturing simplicity, system packaging flexibility, relaxation of assembly alignment tolerances, cost reduction of opto-electronic components and long term reliability and stability.
ERIC Educational Resources Information Center
Maylath, Bruce, Ed.
This proceedings presents 43 papers delivered at the 2001 annual meeting of the Council for Programs in Technical and Scientific Communication (CPTSC). Papers in the proceedings include the following: "Act IV: On Being Less Invisible" (Bill Karis); "Building a Community of Professional Communicators by Mapping Needs and Assets"…
Kansas Communication and Instruction System through Fiber-Optic Transmission.
ERIC Educational Resources Information Center
Kansas State Dept. of Education, Topeka.
Schools and communities will restructure as they move into the next decade. The success of this restructuring will be dependent upon access to and sharing of quality teaching and information through an expanded communication system. One of the major two-way interactive technologies is the fiber-optic cable: a delivery system that will provide…
Design of high-capacity fiber-optic transport systems
NASA Astrophysics Data System (ADS)
Liao, Zhi Ming
2001-08-01
We study the design of fiber-optic transport systems and the behavior of fiber amplifiers/lasers with the aim of achieving higher capacities with larger amplifier spacing. Solitons are natural candidates for transmitting short pulses for high-capacity fiber-optic networks because of its innate ability to use two of fiber's main defects, fiber dispersion and fiber nonlinearity to balance each other. In order for solitons to retain its dynamic nature, amplifiers must be placed periodically to restore powers to compensate for fiber loss. Variational analysis is used to study the long-term stability of a periodical- amplifier system. A new regime of operation is identified which allows the use of a much longer amplifier spacing. If optical fibers are the blood vessels of an optical communication system, then the optical amplifier based on erbium-doped fiber is the heart. Optical communication systems can avoid the use of costly electrical regenerators to maintain system performance by being able to optically amplify the weakened signals. The length of amplifier spacing is largely determined by the gain excursion experienced by the solitons. We propose, model, and demonstrate a distributed erbium-doped fiber amplifier which can drastically reduce the amount of gain excursion experienced by the solitons, therefore allowing a much longer amplifier spacing and superior stability. Dispersion management techniques have become extremely valuable tools in the design of fiber-optic communication systems. We have studied in depth the advantage of different arnplification schemes (lumped and distributed) for various dispersion compensation techniques. We measure the system performance through the Q factor to evaluate the added advantage of effective noise figure and smaller gain excursion. An erbium-doped fiber laser has been constructed and characterized in an effort to develop a test bed to study transmission systems. The presence of mode-partition noise in an erbium-doped fiber laser was experimentally demonstrated. A numerical model has been developed using the Langevin rate equations and its predictions are in qualitative agreement with experimental data.
Midtgård, U; Jelnes, J E
1991-12-01
Many new materials and processes are about to find their way from the research laboratory into industry. The present paper describes some of these processes and provides an overview of possible occupational hazards and a list of chemicals used or produced in the processes. The technological areas that are considered are metal surface treatment (ion implantation, physical and chemical vapor deposition, plasma spraying), powder metallurgy, advanced technical ceramics, and fiber-reinforced plastics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jung, Se-Hui; Park, Jin-Young; Joo, Jung-Hoon
2011-07-15
Membrane bridges are key cellular structures involved in intercellular communication; however, dynamics for their formation are not well understood. We demonstrated the formation and regulation of novel extracellular ultrathin fibers in NIH3T3 cells using confocal and atomic force microscopy. At adjacent regions of neighboring cells, phorbol 12-myristate 13-acetate (PMA) and glucose oxidase induced ultrathin fiber formation, which was prevented by Trolox, a reactive oxygen species (ROS) scavenger. The height of ROS-sensitive ultrathin fibers ranged from 2 to 4 nm. PMA-induced formation of ultrathin fibers was inhibited by cytochalasin D, but not by Taxol or colchicine, indicating that ultrathin fibers mainlymore » comprise microfilaments. PMA-induced ultrathin fibers underwent dynamic structural changes, resulting in formation of intercellular membrane bridges. Thus, these fibers are formed by a mechanism(s) involving ROS and involved in formation of intercellular membrane bridges. Furthermore, ultrastructural imaging of ultrathin fibers may contribute to understanding the diverse mechanisms of cell-to-cell communication and the intercellular transfer of biomolecules, including proteins and cell organelles.« less
Coupling efficiency of laser beam to multimode fiber for free space optical communication
NASA Astrophysics Data System (ADS)
Arisa, Suguru; Takayama, Yoshihisa; Endo, Hiroyuki; Shimizu, Ryosuke; Fujiwara, Mikio; Sasaki, Masahide
2017-11-01
Recently, the free space optical (FSO) communications have been widely studied as an alternative for large capacity communications and its possible implementation in satellite and terrestrial laser links. In satellite communications, clouds can strongly attenuate the laser signal that would lead to high bit-error rates or temporal unavailability of the link. To overcome the cloud coverage effects, often site diversity technique is implemented. When using multiple ground stations though, simplified optical system is required to allow the usage of more flexible approaches. In terrestrial laser communications, several methods for optical system simplification by using a multimode fiber (MMF) have been proposed.
NASA Astrophysics Data System (ADS)
Dua, Puneit
Increased demand for larger bandwidth and longer inter-amplifiers distances translates to higher power budgets for fiber optic communication systems in order to overcome large splitting losses and achieve acceptable signal-to-noise ratios. Due to their unique design ytterbium sensitized erbium doped, double clad fiber amplifiers; offer significant increase in the output powers that can be obtained. In this thesis we investigate, a one-stage, high power erbium and ytterbium co-doped double clad fiber amplifier (DCFA) with output power of 1.4W, designed and built in our lab. Experimental demonstration and numerical simulation techniques have been used to systematically study the applications of such an amplifier and the effects of incorporating it in various fiber optic communication systems. Amplitude modulated subcarrier multiplexed (AM-SCM) CATV distribution experiment has been performed to verify the feasibility of using this amplifier in an analog/digital communication system. The applications of the amplifier as a Fabry-Perot and ring fiber laser with an all-fiber cavity, a broadband supercontinuum source and for generation of high power, short pulses at 5GHz have been experimentally demonstrated. A variety of observable nonlinear effects occur due to the high intensity of the optical powers confined in micron-sized cores of the fibers, this thesis explores in detail some of these effects caused by using the high power Er/Yb double clad fiber amplifier. A fiber optic based analog/digital CATV system experiences composite second order (CSO) distortion due to the interaction between the gain tilt---the variation of gain with wavelength, of the doped fiber amplifier and the wavelength chirp of the directly modulated semiconductor laser. Gain tilt of the Er/Yb co-doped fiber amplifier has been experimentally measured and its contribution to the CSO of the system calculated. Theoretical analysis of a wavelength division multiplexed system with closely spaced channels has been carried out to show that crosstalk can occur due to the four-wave mixing products generated inside the high power Er/Yb DCFA. A model for parametric amplification due to four-wave mixing has been developed and used to analyze its application for short pulse generation and high speed optical time division multiplexing.
ERIC Educational Resources Information Center
Coggio, Grace Leinbach
2010-01-01
This dissertation examines the diffusion of an innovative information technology system across multiple cultures between 2000 and 2006. Developed and implemented by technical communicators in the technical communication department of a global medical device company, the Advanced Single-Source Authoring and Publication System (ASAPS) brought…
ERIC Educational Resources Information Center
Wang, Junhua
2013-01-01
Scholars in business and technical communication have continuously made efforts to look for effective teaching approaches for cross-cultural business and technical communication; however, little research has been conducted to study the process by which students develop intercultural competence; fewer studies have been conducted to assess learners'…
ERIC Educational Resources Information Center
Murdock, Phil, Comp.
Compiled from responses to a survey of 36 universities offering doctorates in rhetoric, composition, language, or technical communication, and updated using research and dissertation indexes and bibliographies, this bibliography summarizes doctoral research in technical communication since 1975. The 35 titles deal with a variety of topics,…
ERIC Educational Resources Information Center
Battalio, John T.
2002-01-01
Describes the influence that Extensible Markup Language (XML) will have on the software documentation process and subsequently on the curricula of advanced undergraduate and master's programs in technical communication. Recommends how curricula of advanced undergraduate and master's programs in technical communication ought to change in order to…
ERIC Educational Resources Information Center
Fan, Jiang-Ping
2006-01-01
In this article, the author demonstrates that the semiotic model proposed by Charles Morris enables us to optimize our understanding of technical communication practices and provides a good point of inquiry. To illustrate this point, the author exemplifies the semiotic approaches by scholars in technical communication and elaborates Morris's model…
Design of a stabilized, compact gimbal for space-based free space optical communications (FSOC)
NASA Astrophysics Data System (ADS)
Cline, A.; Shubert, P.; McNally, J.; Jacka, N.; Pierson, R.
2017-02-01
Data transmits via optical communications through fibers at 10's of Terabits per second. Given the recent rapid explosion for bandwidth and competing demand for radio frequency (RF) spectrum allocations among differing interests, the need for space-based free space optical communications (FSOC) systems is ever increasing. FSOC systems offer advantages of higher data rates, smaller size and weight, narrower beam divergence, and lower power than RF systems. Lightweight, small form factor, and high performance two-axis gimbals are of strong interest for satellite FSOC applications. Small gimbal and optical terminal designs are important for widespread implementation of optical communications systems; in particular, for satellite-to-satellite crosslinks where the advantages of more secure communications links (Lower Probability of Intercept (LPI)/Lower Probability of Detect (LPD)) are very important. We developed design concepts for a small gimbal focusing on the use of commercial off-the-shelf (COTS) subsystems to establish their feasible implementation against the pointing stabilization, size, weight and power (SWaP), and performance challenges. The design drivers for the gimbal were weight, the elevation and azimuth field of regards, the form factor envelope (1U CubeSats), 100 μrad pointing accuracy, and 10 degrees per second slew capability. Innovations required in this development included a continuous fiber passed through an Azimuth Fiber Wrap and Elevation Fiber Wrap, overcoming typical mechanical and stress related limitations encountered with fiber optic cable wraps. In this presentation, we describe the configuration trades and design of such a gimbal.
Fiber-Optic Communication Links Suitable for On-Board Use in Modern Aircraft
NASA Technical Reports Server (NTRS)
Nguyen, Hung; Ngo, Duc; Alam, Mohammad F.; Atiquzzaman, Mohammed; Sluse, James; Slaveski, Filip
2004-01-01
The role of the Advanced Air Transportation Technologies program undertaken at the NASA Glenn Research Centers has been focused mainly on the improvement of air transportation safety, with particular emphasis on air transportation communication systems in on-board aircraft. The conventional solutions for digital optical communications systems specifically designed for local/metro area networks are, unfortunately, not capable of transporting the microwave and millimeter RF signals used in avionics systems. Optical networks capable of transporting RF signals are substantially different from the standard digital optical communications systems. The objective of this paper is to identify a number of different communication link architectures for RF/fiber optic transmission using a single backbone fiber for carrying VHF and UHF RF signals in the aircraft. To support these architectures, two approaches derived from both hybrid RF-optical and all-optical processing methodologies are discussed with single and multiple antennas for explicitly transporting VHF and UHF signals, while the relative merits and demerits of each architecture are also addressed. Furthermore, the experimental results of wavelength division multiplexing (WDM) link architecture from our test-bed platform, configured for aircraft environment to support simultaneous transmission of multiple RF signals over a single optical fiber, exhibit no appreciable signal degradation at wavelengths of both 1330 and 1550 nm, respectively. Our measurements of signal to noise ratio carried out for the transmission of FM and AM analog modulated signals at these wavelengths indicate that WDM is a fiber optic technology which is potentially suitable for avionics applications.
NASA Astrophysics Data System (ADS)
Parekh, Devang
With the rise of mobile (cellphones, tablets, notebooks, etc.) and broadband wireline communications (Fiber to the Home), there are increasing demands being placed on transmitters for moving data from device to device and around the world. Digital and analog fiber-optic communications have been the key technology to meet this challenge, ushering in ubiquitous Internet and cable TV over the past 20 years. At the physical layer, high-volume low-cost manufacturing of semiconductor optoelectronic devices has played an integral role in allowing for deployment of high-speed communication links. In particular, vertical cavity surface emitting lasers (VCSEL) have revolutionized short reach communications and are poised to enter more markets due to their low cost, small size, and performance. However, VCSELs have disadvantages such as limited modulation performance and large frequency chirp which limits fiber transmission speed and distance, key parameters for many fiber-optic communication systems. Optical injection locking is one method to overcome these limitations without re-engineering the VCSEL at the device level. By locking the frequency and phase of the VCSEL by the direct injection of light from another laser oscillator, improved device performance is achieved in a post-fabrication method. In this dissertation, optical injection locking of VCSELs is investigated from an applications perspective. Optical injection locking of VCSELs can be used as a pathway to reduce complexity, cost, and size of both digital and analog fiber-optic communications. On the digital front, reduction of frequency chirp via bit pattern inversion for large-signal modulation is experimentally demonstrated showing up to 10 times reduction in frequency chirp and over 90 times increase in fiber transmission distance. Based on these results, a new reflection-based interferometric model for optical injection locking was established to explain this phenomenon. On the analog side, the resonance frequency enhancement was exploited for millimeter-wave radio over fiber communications. Experimental demonstration of 4 Gb/s data transmission over 20 km of fiber and 3 m of wireless transmission at a 60 GHz carrier frequency was achieved. Additionally, optical injection of multi-transverse mode (MM) VCSELs was investigated showing record resonance frequency enhancement of > 54 GHz and 3-dB bandwidth of 38 GHz. Besides these applications, a number of other intriguing applications are also discussed, including an optoelectronic oscillator (OEO) and wavelength-division multiplexed passive optical networks (WDM-PON). Finally, the future of optical injection locking and its direction going forward will be discussed.
Fiber Optics and Library Technology.
ERIC Educational Resources Information Center
Koenig, Michael
1984-01-01
This article examines fiber optic technology, explains some of the key terminology, and speculates about the way fiber optics will change our world. Applications of fiber optics to library systems in three major areas--linkage of a number of mainframe computers, local area networks, and main trunk communications--are highlighted. (EJS)
Optical wireless communication in data centers
NASA Astrophysics Data System (ADS)
Arnon, Shlomi
2018-01-01
In the last decade data centers have become a crucial element in modern human society. However, to keep pace with internet data rate growth, new technologies supporting data center should develop. Integration of optical wireless communication (OWC) in data centers is one of the proposed technologies as augmented technology to the fiber network. One implementation of the OWC technology is deployment of optical wireless transceiver on top of the existing cable/fiber network as extension to the top of rack (TOR) switch; in this way, a dynamic and flexible network is created. Optical wireless communication could reduce energy consumption, increase the data rate, reduce the communication latency, increase flexibility and scalability, and reduce maintenance time and cost, in comparison to extra fiber network deployment. In this paper we review up to date literature in the field, propose an implementation scheme of OWC network, discuss ways to reduce energy consumption by parallel link communication and report preliminary measurement result of university data center environment.
Lee, Jaeyul; Kwon, Hyungwoo; Song, Jaewon; Jeon, Mansik; Kim, Jeehyun
2017-01-01
A handheld line information reader and a line information generator were developed for the efficient management of optical communication lines. The line information reader consists of a photo diode, trans-impedance amplifier, voltage amplifier, microcontroller unit, display panel, and communication modules. The line information generator consists of a laser diode, laser driving circuits, microcontroller unit, and communication modules. The line information reader can detect the optical radiation field of the test line by bending the optical fiber. To enhance the sensitivity of the line information reader, an additional lens was used with a focal length of 4.51 mm. Moreover, the simulation results obtained through BeamPROP® software from Synopsys, Inc. demonstrated a stronger optical radiation field of the fiber due to a longer transmission wavelength and larger bending angle of the fiber. Therefore, the developed devices can be considered as useful tools for the efficient management of optical communication lines. PMID:28837058
ERIC Educational Resources Information Center
Ding, Daniel; Jablonski, John
2001-01-01
Relates the authors' experience teaching technical writing for two weeks at Suzhou University in China. Discusses activities; examines four technical writing textbooks purchased there; and offers suggestions about how technical communication might be established as a separate academic discipline in Chinese universities. Discusses technical…
Teaching Intracultural and Intercultural Communication: A Critique and Suggested Method.
ERIC Educational Resources Information Center
DeVoss, Danielle; Jasken, Julia; Hayden, Dawn
2002-01-01
Summarizes recent literature about the importance of paying attention to intercultural communication. Analyzes the productive approaches in popular business and technical communication textbooks. Presents five challenges for business and technical communication teachers to consider. Includes teaching modules that address these challenges. Notes…
Wide band fiber-optic communications
NASA Technical Reports Server (NTRS)
Bates, Harry E.
1993-01-01
A number of optical communication lines are now in use at the Kennedy Space Center (KSC) for the transmission of voice, computer data and video signals. At the present time most of these channels utilize a single carrier wavelength centered near 1300 nm. As a result of previous work the bandwidth capacity of a number of these channels is being increased by transmitting another signal in the 1550 nm region on the same fiber. This is accomplished by means of wavelength division multiplexing (WDM). It is therefore important to understand the bandwidth properties of the installed fiber plant. This work developed new procedures for measuring the bandwidth of fibers in both the 1300nm and 1550nm region. In addition, a preliminary study of fiber links terminating in the Engineering Development Laboratory was completed.
Li, Chung-Yi; Lu, Hai-Han; Lu, Ting-Chieh; Chu, Chien-An; Chen, Bo-Rui; Lin, Chun-Yu; Peng, Peng-Chun
2015-12-14
A hybrid lightwave transmission system for cable television (CATV)/millimeter-wave (MMW)/baseband (BB) signal transmission based on fiber-wired/fiber-wireless/fiber-visible laser light communication (VLLC) integrations is proposed and demonstrated. For down-link transmission, the light is intensity-modulated with 50-550 MHz CATV signal and optically promoted from 25 GHz radio frequency (RF) signal to 10 Gbps/50 GHz and 20 Gbps/100 GHz MMW data signals based on fiber-wired and fiber-wireless integrations. Good performances of carrier-to-noise ratio (CNR), composite second-order (CSO), composite triple-beat (CTB), and bit error rate (BER) are obtained over a 40-km single-mode fiber (SMF) and a 10-m RF wireless transport. For up-link transmission, the light is successfully intensity-remodulated with 5-Gbps BB data stream based on fiber-VLLC integration. Good BER performance is achieved over a 40-km SMF and a 10-m free-space VLLC transport. Such a hybrid CATV/MMW/BB lightwave transmission system is an attractive alternative, it gives the benefits of a communication link for broader bandwidth and higher transmission rate.
Technical communication: Notes toward defining discipline
NASA Technical Reports Server (NTRS)
Rubens, P. M.
1981-01-01
In the field of technical communication, definitions posited in virtually any major text violate every major rule of definitions. The most popular method for defining the field is to state that technical writing is any writing that supports technology or technological activities. There is a need for a nice yardstick for measuring what "technology" is. Some ways in which the field can be defined in a tightly structured empirical way and some implications of technical communication for a humanistic education in a technological age are suggested.
ERIC Educational Resources Information Center
Thompson, Isabelle
1999-01-01
Identifies 40 articles about women and feminism published in five technical communication journals in a period of nine years. Notes major themes, all concerning inclusion. Concludes that although research about women and feminism has been accepted as part of the scholarly purview of technical communication, the ways in which this research has…
16 CFR 303.8 - Procedure for establishing generic names for manufactured fibers.
Code of Federal Regulations, 2010 CFR
2010-01-01
... the applicant to be pertinent to the application, including technical data in the form of test methods..., within sixty (60) days, either deny the application or assign to the fiber a numerical or alphabetical...
Fiber reinforced polymer bridge decks : [technical summary].
DOT National Transportation Integrated Search
2011-01-01
A number of researchers have addressed the use of Fiber Reinforced Polymer (FRP) deck as a replacement solution for deteriorated bridge decks made of traditional materials. The use of new, advanced materials such as FRP is advantageous when the bridg...
Phase A design study of microgravity fluoride fiber puller
NASA Technical Reports Server (NTRS)
Workman, Gary L.; Smith, Guy A.; Kosten, Susan
1994-01-01
Improved transmission properties for fluoride fibers due to space processing has great potential for commercial benefits. Phase A design study will determine conceptual feasibility and provide initial definition of the technical requirements and design issues for space.
Code of Federal Regulations, 2014 CFR
2014-01-01
... primary television or radio broadcast station, including, but not limited to, coaxial cable, optical fiber..., optical fiber communications equipment, and other means of transmitting, emitting, storing, and receiving..., and coaxial or fiber optic cable. Noncommercial educational broadcast station or public broadcast...
Code of Federal Regulations, 2013 CFR
2013-01-01
... primary television or radio broadcast station, including, but not limited to, coaxial cable, optical fiber..., optical fiber communications equipment, and other means of transmitting, emitting, storing, and receiving..., and coaxial or fiber optic cable. Noncommercial educational broadcast station or public broadcast...
Code of Federal Regulations, 2012 CFR
2012-01-01
... primary television or radio broadcast station, including, but not limited to, coaxial cable, optical fiber..., optical fiber communications equipment, and other means of transmitting, emitting, storing, and receiving..., and coaxial or fiber optic cable. Noncommercial educational broadcast station or public broadcast...
A simple system for 160GHz optical terahertz wave generation and data modulation
NASA Astrophysics Data System (ADS)
Li, Yihan; He, Jingsuo; Sun, Xueming; Shi, Zexia; Wang, Ruike; Cui, Hailin; Su, Bo; Zhang, Cunlin
2018-01-01
A simple system based on two cascaded Mach-Zehnder modulators, which can generate 160GHz optical terahertz waves from 40GHz microwave sources, is simulated and tested in this paper. Fiber grating filter is used in the system to filter out optical carrier. By properly adjusting the modulator DC bias voltages and the signal voltages and phases, 4-tupling optical terahertz wave can be generated with fiber grating. This notch fiber grating filter is greatly suitable for terahertz over fiber (TOF) communication system. This scheme greatly reduces the cost of long-distance terahertz communication. Furthermore, 10Gbps digital signal is modulated in the 160GHz optical terahertz wave.
1998-02-05
Scarning electron microscope images of the surface of ZBLAN fibers pulled in microgravity (ug) and on Earth (1g) show the crystallization that normally occurs in ground-based processing. The face of each crystal will reflect or refract a portion of the optical signal, thus degrading its quality. NASA is conducting research on pulling ZBLAN fibers in the low-g environment of space to prevent crystallization that limits ZBLAN's usefulness in optical fiber-based communications. ZBLAN is a heavy-metal fluoride glass that shows exdeptional promise for high-throughput communications with infrared lasers. Photo credit: NASA/Marshall Space Flight Center
Superdense Coding over Optical Fiber Links with Complete Bell-State Measurements
Williams, Brian P.; Sadlier, Ronald J.; Humble, Travis S.
2017-02-01
Adopting quantum communication to modern networking requires transmitting quantum information through a fiber-based infrastructure. In this paper, we report the first demonstration of superdense coding over optical fiber links, taking advantage of a complete Bell-state measurement enabled by time-polarization hyperentanglement, linear optics, and common single-photon detectors. Finally, we demonstrate the highest single-qubit channel capacity to date utilizing linear optics, 1.665 ± 0.018, and we provide a full experimental implementation of a hybrid, quantum-classical communication protocol for image transfer.
Career Directions--Fiber Optic Installer
ERIC Educational Resources Information Center
Tech Directions, 2012
2012-01-01
Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber that is roughly the diameter of a human hair. The light forms an electromagnetic carrier wave that is modulated to carry information. Each optical fiber is capable of carrying an enormous amount of…
Research on Damage Models for Continuous Fiber Composites
1988-07-01
r ~.F (~ Mechanics and Materials Center TEXAS A&M UNIVERSITY College Station, Texas RESEARCH ON DAMAGE MODELS FOR CONTINUOUS FIBER COMPOSITES Final...Washington, DC 20332 11. TITLE (Include Security Clas=fication) Research on Damage Models for Continuous Fiber Composites - Final Technical Report 1...GROUP SUB-GROU ::=, COMPOsites ) continuum mechanics , ~ idamage, internal state variables V experimental mechanics, laminated composites o 19. ABSTRACT
Adaptation of FIBER for Forest Inventory and Analysis growth projections in the State of Maine
Dale S. Solomon; Thomas B. Brann; Lawrence E. Caldwell
2000-01-01
The model FIBER (Forest Increment Based on Ecological Rationale) was selected by the Technical Review Team on the Sustainability of Timber Supplies in the State of Maine to construct yield information using USDA Forest Service Forest Inventory and Analysis (FIA) field data. FIBER habitat criteria based on soil characteristics, species composition of overstory, and...
Wideband fiber optic communications link
NASA Astrophysics Data System (ADS)
Bray, J. R.
1984-12-01
This thesis examined the feasibility of upgrading a nine port fiber optic bundle telecommunications system to a single strand fiber optic system. Usable pieces of equipment were identified and new Light Emitting Diodes (LED), Photodetectors and single strand SMA styled fiber optic connectors were ordered. Background research was conducted in the area of fiber optic power launching, fiber losses, connector losses and efficiencies. A new modulation/demodulation circuit was designed and constructed using parts from unused equipment. A new front panel was constructed to house the components, switches and connectors. A 2-m piece of optical fiber was terminated with the new connectors and tested for connector loss, numeric aperture and attenuation. The new LED was characterized by its emission radiation pattern and the entire system was tested for functional operation, frequency response and bandwidth of operation. An operations manual was prepared to ensure proper use in the future. The result was a two piece, single strand, fiber optic communications systems fully TTL compatible, capable of transmitting digital signals from 80 Kbit/sec to 20 Mbit/sec. The system was tested in a half duplex mode using both baseband and carrier modulated signals.
Using Scientific and Industrial Films in Teaching Technical Communication.
ERIC Educational Resources Information Center
Veeder, Gerry
A film course especially designed for technical communication students can illustrate basic film concepts and techniques while showing how film effectively communicates ideas in an industrial and scientific communication system. After a basic introduction to film terms, the study of actual scientific and industrial films demonstrates the following…
ERIC Educational Resources Information Center
Engelke, Christopher Robert
2013-01-01
Technically Speaking: On the Structure and Experience of Interaction Involving Augmentative Alternative Communications examines the ways that communication is structured and experienced by looking at interactions involving augmented communicators--people with severe speech disabilities who use forms of assistive technology in order to communicate…
Code of Federal Regulations, 2013 CFR
2013-04-01
... data communications between system components? 547.15 Section 547.15 Indians NATIONAL INDIAN GAMING... AND EQUIPMENT § 547.15 What are the minimum technical standards for electronic data communications between system components? (a) Sensitive data. Communication of sensitive data must be secure from...
Code of Federal Regulations, 2014 CFR
2014-04-01
... data communications between system components? 547.15 Section 547.15 Indians NATIONAL INDIAN GAMING... AND EQUIPMENT § 547.15 What are the minimum technical standards for electronic data communications between system components? (a) Sensitive data. Communication of sensitive data must be secure from...
ERIC Educational Resources Information Center
Council for Programs in Technical and Scientific Communication.
Based on the theme of connections in technical and scientific communication, this proceedings presents 47 papers delivered at the 1997 annual meeting of the Council for Programs in Technical and Scientific Communication (CPTSC). Papers in the proceedings are divided into 10 sections: (1) Theoretical Connections; (2) Legal and Ethical Connections;…
ERIC Educational Resources Information Center
Carson, David L., Ed.
Prepared by representatives of industry, government, and the educational community, the papers in this collection were drawn from a conference that addressed a variety of issues of interest to the field of technical communication. Specific topics discussed in the papers are as follows: (1) the role of the Society for Technical Communication in…
Fiber-Optic Network Architectures for Onboard Avionics Applications Investigated
NASA Technical Reports Server (NTRS)
Nguyen, Hung D.; Ngo, Duc H.
2003-01-01
This project is part of a study within the Advanced Air Transportation Technologies program undertaken at the NASA Glenn Research Center. The main focus of the program is the improvement of air transportation, with particular emphasis on air transportation safety. Current and future advances in digital data communications between an aircraft and the outside world will require high-bandwidth onboard communication networks. Radiofrequency (RF) systems, with their interconnection network based on coaxial cables and waveguides, increase the complexity of communication systems onboard modern civil and military aircraft with respect to weight, power consumption, and safety. In addition, safety and reliability concerns from electromagnetic interference between the RF components embedded in these communication systems exist. A simple, reliable, and lightweight network that is free from the effects of electromagnetic interference and capable of supporting the broadband communications needs of future onboard digital avionics systems cannot be easily implemented using existing coaxial cable-based systems. Fiber-optical communication systems can meet all these challenges of modern avionics applications in an efficient, cost-effective manner. The objective of this project is to present a number of optical network architectures for onboard RF signal distribution. Because of the emergence of a number of digital avionics devices requiring high-bandwidth connectivity, fiber-optic RF networks onboard modern aircraft will play a vital role in ensuring a low-noise, highly reliable RF communication system. Two approaches are being used for network architectures for aircraft onboard fiber-optic distribution systems: a hybrid RF-optical network and an all-optical wavelength division multiplexing (WDM) network.
Waveguide Studies for Fiber Optics and Optical Signal Processing Applications.
1980-04-01
AO-A086 115 UNI!VERtSIT? OF SOUTIUR CALEPCRNA LOS AMUSS / 5 WAVGUIDE STUIES15 FOR FEB53 OpTECS AND OpTICAL SEOSA.o P /0Ksu-y "/6 UNLSIIDAPR N0 E...SAMUE Flola-??-c-sa UNCASZFIORAC-M-8042 U Final Technical Report (1 1April 1950 L V ~ WAVEGUIDE STUDIES FOR FIBER OPTICS AND OPTICAL SIGNAL PROCESSING...and Subtitle) 081 6&4JODO )EI YAVECUIDESTUDIES FOR JIBER OPTICS ANDL 7 Final ,T/echnical epoErt, OPTICAL SI’tNAL PROCESSING APPLICATIONS.4 11 Se 77
Fiber optics: A research paper
NASA Technical Reports Server (NTRS)
Drone, Melinda M.
1987-01-01
Some basic aspects concerning fiber optics are examined. Some history leading up to the development of optical fibers which are now used in the transmission of data in many areas of the world is discussed. Basic theory of the operation of fiber optics is discussed along with methods for improving performance of the optical fiber through much research and design. Splices and connectors are compared and short haul and long haul fiber optic networks are discussed. Fiber optics plays many roles in the commercial world. The use of fiber optics for communication applications is emphasized.
Communication Sciences and Health Sciences.
ERIC Educational Resources Information Center
Lane, Shelley D.
1981-01-01
Technical skills and interpersonal communication contribute to diagnosing diseases, and evidence suggests that the quality of the interpersonal relationship can significantly influence the outcome of treatments that appear to depend solely on technical factors. Because communication directly influences health-related outcomes, communication…
ERIC Educational Resources Information Center
Cary, Penny J.; Sweeney, Kevin F.
A study examined the need and demand for communication skills for employees in the technical fields for which Southern Maine Vocational Technical Institute offers programs of academic preparation. Two members of the Institute's English Department interviewed representatives of organizations that have hired technical program graduates. Further…
NASA Astrophysics Data System (ADS)
de Assis, Foluke S.; Netto, Pedro A.; Margem, Frederico M.; Monteiro, Artur R. P. Junior Sergio N.
Synthetic fibers are being replaced gradually by natural materials such as lignocellulosic fibers. Compared to synthetic fibers, natural fibers have shown advantages in technical aspects such as environmental and economic. So there is a growing international interest in the use of those fibers. The banana fiber presents significant properties to be studied, but until now few thermal properties on banana fiber as reinforcement of polyester matrix were performed. The present work had as its objective to investigate, by photoacoustic spectroscopy and photothermal techniques the thermal properties of diffusivity, specific heat capacity and conductivity for polyester composites reinforced with banana fibers. In the polyester matrix will be added up to 30% in volume of continuous and aligned banana fibers. These values show that the incorporation of banana fibers in the polyester matrix changes its thermal properties.
What Consultation and Freelance Writing Can Do for You and Your Students
ERIC Educational Resources Information Center
Muller, John A.
1978-01-01
Urges teachers of technical writing and graduate students in English to get off campus and engage in giving businesses advice intended to solve problems in technical communication, editing technical communication publications, and researching and writing such publications. (GW)
Commentary: Sexism, Sex Stereotyping, and the Technical Writer.
ERIC Educational Resources Information Center
Veiga, Nancy E.
1989-01-01
Discusses the impact of possible sex-based differences in communication styles on the technical writer's job. Argues that technical writers can choose to use both male and female communication styles to acknowledge multiple audiences and to improve the quality of their documents. (KEH)
Survivability Enhancements for Military Communications Satellites
1990-01-01
Communications Agency, Jan 1984. Townley , Ralph K., David W. Brown, Martin 0. Bernet, and Bernard L. Pankowski. "Selected Issues in DCS Integration...K. Townley , David W. Brown, Martin 0. Bernet, and Bernard L. Pankowski, "Selected Issues in DCS Technical Integration," Technical paper prepared by...34 Technical Note 11-82. Defense Communications Agency, Jan 1984. Townley , Ralph K., David W. Brown, Martin 0. Bernet, and Bernard L. Pankowski. "Selected
Strategy-Based Technical Instruction: Development and Evaluation
1988-08-01
scripts dependant on target tasks and the outcomes desired, and to the use of node-link knowledge maps as communications props. In addition, we have...information "on the job" - communicate with others in the task environment; - monitor, diagnose, and correct problems associated with critical tasks... communicated . Technical Training Goals The individual in a technical training scenario is expected to achieve a wide variety of goals. These goals can
Digital image analysis techniques for fiber and soil mixtures : technical summary.
DOT National Transportation Integrated Search
1999-05-01
This project used to innovative technologies of digital image analysis for the characterization of a material currently being considered for broad use at DOTD. The material under consideration is a mixture of fiber and soil for use in the stabilizati...
2016-04-01
DEVELOPING TOPOLOGICAL INSULATOR FIBER BASED PHOTON PAIRS SOURCE FOR ULTRAFAST OPTOELECTRONIC APPLICATIONS NORTHWESTERN UNIVERSITY...REPORT TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) APRIL 2015 – DEC 2015 4. TITLE AND SUBTITLE DEVELOPING TOPOLOGICAL INSULATOR FIBER BASED...in developing a new source for the production of correlated/entangled photon pairs based on the unique nanolayer properties of topological insulator
Lu, Hai-Han; Li, Chung-Yi; Lu, Ting-Chien; Wu, Chang-Jen; Chu, Chien-An; Shiva, Ajay; Mochii, Takao
2016-02-01
A bidirectional fiber-wireless and fiber-visible-laser-light-communication (VLLC) transmission system based on an optoelectronic oscillator (OEO)-based broadband light source (BLS) and a reflective semiconductor optical amplifier (RSOA) is proposed and experimentally demonstrated. Through an in-depth observation of such bidirectional fiber-wireless and fiber-VLLC transmission systems, good bit error rate performances are obtained over a 40 km single-mode fiber and a 10 m RF/optical wireless transport. Such a bidirectional fiber-wireless and fiber-VLLC transmission system is an attractive option for providing broadband integrated services.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-11
... DEPARTMENT OF HOMELAND SECURITY [Docket No. DHS-2010-0006] Agency Information Collection Activities: Cybersecurity and Communications Technical Assistance Request and Evaluation AGENCY: National... Programs Directorate (NPPD), Office of Cybersecurity and Communications (CS&C), Office of Emergency...
Partial hyperbolicity and attracting regions in 3-dimensional manifolds
NASA Astrophysics Data System (ADS)
Potrie, Rafael
The need for reliable, fiber-based sources of entangled and paired photons has intensified in recent years because of potential uses in optical quantum communication and computing. In particular, indistinguishable photon sources are an inherent part of several quantum communication protocols and are needed to establish the viability of quantum communication networks. This thesis is centered around the development of such sources at telecommunication-band wavelengths. In this thesis, we describe experiments on entangled photon generation and the creation of quantum logic gates in the C-band, and on photon indistinguishability in the O-band. These experiments utilize the four-wave mixing process in fiber which occurs as a result of the Kerr nonlinearity, to create paired photons. To begin, we report the development of a source of 1550-nm polarization entangled photons in fiber. We then interface this source with a quantum Controlled-NOT gate, which is a universal quantum logic gate. We set experimental bounds on the process fidelity of the Controlled-NOT gate. Next, we report a demonstration of quantum interference between 1310-nm photons produced in independent sources. We demonstrate high quantum interference visibility, a signature of quantum indistinguishability, while using distinguishable pump photons. Together, these efforts constitute preliminary steps toward establishing the viability of fiber-based quantum communication, which will allow us to utilize existing infrastructure for implementing quantum communication protocols.
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.; Flammia, Madelyn; Kennedy, John M.
1994-01-01
Until the recent dissolution of the Soviet Union, the Communist Party exerted a strict control of access to and dissemination of scientific and technical information (STI). This article presents models of the Soviet-style information society and the Western-style information society and discusses the effects of centralized governmental control of information on Russian technical communication practices. The effects of political control on technical communication are then used to interpret the results of a survey of Russian and U.S. aerospace engineers and scientists concerning the time devoted to technical communication, their collaborative writing practices and their attitudes toward collaboration, the kinds of technical documents they produce and use, and their use of computer technology, and their use of and the importance to them of libraries and technical information centers. The data are discussed in terms of tentative conclusions drawn from the literature. Finally, we conclude with four questions concerning government policy, collaboration, and the flow of STI between Russian and U.S. aerospace engineers and scientists.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.
1993-01-01
As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of India and U.S. aerospace engineers and scientists. Both studies have the same seven objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; fifth, to determine the use and importance of computer and information technology to them; sixth, to determine their use of electronic networks; and seventh, to determine their use of foreign and domestically produced technical reports. A self-administered questionnaire was distributed to aerospace engineers and scientists at the Indian Institute of Science and the NASA Langley Research Center. The completion rates for the India and U.S. surveys were 48 and 53 percent, respectively. Responses of the India and U.S. participants to selected questions are presented in this report.
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.; Kennedy, John M.
1993-01-01
As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. Both studies have the same seven objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; fifth, to determine the use and importance of computer and information technology to them; sixth, to determine their use of electronic networks; and seventh, to determine their use of foreign and domestically produced technical reports. A self-administered questionnaire was distributed to aerospace engineers and scientists at the National Aerospace Laboratory (NLR), and NASA Ames Research Center, and the NASA Langley Research Center. The completion rates for the Dutch and U.S. surveys were 55 and 61 percent, respectively. Responses of the Dutch and U.S. participants to selected questions are presented.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.
1994-01-01
As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Japanese and U.S. aerospace engineers and scientists. Both studies have the same seven objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third; to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; fifth, to determine the use and importance of computer and information technology to them; sixth, to determine their use of electronic networks; and seventh, to determine their use of foreign and domestically produced technical reports. A self-administered questionnaire was distributed to aerospace engineers and scientists in Japan and at the NASA Ames Research Center and the NASA Langley Research Center. The completion rates for the Japanese and U.S. surveys were 85 and 61 percent, respectively. Responses of the Japanese and U.S. participants to selected questions are presented in this report.
Gigabit Ethernet: A Technical Assessment.
ERIC Educational Resources Information Center
Axner, David
1997-01-01
Describes gigabit ethernet for LAN (local area network) technology that will expand ethernet bandwidth. Technical details are discussed, including protocol stacks, optical fiber, deployment strategy for performance improvement, ATM (Asynchronous Transfer Mode), real-time protocol, reserve reservation protocol, and standards. (LRW)
ERIC Educational Resources Information Center
Tebeaux, Elizabeth
1998-01-01
Examines the style of early women technical writers to show that plain English existed before Sir Francis Bacon and received its impetus from the utilitarian attitude that pervaded the 1475-1700 period. Finds that technical communication studied from this historical perspective deepens students' awareness of technical communication's roots in the…
ERIC Educational Resources Information Center
Williams, Sean D.
2010-01-01
This article argues that in spite of some attempts to expand the diversity of approaches in Technical Communication, the field remains rooted in an expedient, managerial, techno-rational discourse, where discourse is understood as the values that guide research, practice, and teaching. The article draws on approaches from Communication Studies,…
Zhang, Junfeng; Chen, Wei; Gao, Mingyi; Shen, Gangxiang
2017-10-30
In this work, we proposed two k-means-clustering-based algorithms to mitigate the fiber nonlinearity for 64-quadrature amplitude modulation (64-QAM) signal, the training-sequence assisted k-means algorithm and the blind k-means algorithm. We experimentally demonstrated the proposed k-means-clustering-based fiber nonlinearity mitigation techniques in 75-Gb/s 64-QAM coherent optical communication system. The proposed algorithms have reduced clustering complexity and low data redundancy and they are able to quickly find appropriate initial centroids and select correctly the centroids of the clusters to obtain the global optimal solutions for large k value. We measured the bit-error-ratio (BER) performance of 64-QAM signal with different launched powers into the 50-km single mode fiber and the proposed techniques can greatly mitigate the signal impairments caused by the amplified spontaneous emission noise and the fiber Kerr nonlinearity and improve the BER performance.
Advanced optical fiber communication systems
NASA Astrophysics Data System (ADS)
Kazovsky, Leonid G.
1994-03-01
Our research is focused on three major aspects of advanced optical fiber communication systems: dynamic wavelength division multiplexing (WDM) networks, fiber nonlinearities, and high dynamic range coherent analog optical links. In the area of WDM networks, we have designed and implemented two high-speed interface boards and measured their throughput and latency. Furthermore, we designed and constructed an experimental PSK/ASK transceiver that simultaneously transmits packet-switched ASK data and circuit-switched PSK data on the same optical carrier. In the area of fiber nonlinearities, we investigated the theoretical impact of modulation frequency on cross-phase modulation (XPM) in dispersive fibers. In the area of high dynamic range coherent analog optical links, we developed theoretical expressions for the RF power transfer ratio (or RF power gain) and the noise figure (NF) of angle-modulated links. We then compared the RF power gains and noise figures of these links to that of an intensity modulated direct detection (DD) link.
Optical fibers for the distribution of frequency and timing references
NASA Technical Reports Server (NTRS)
Lutes, G. F.
1981-01-01
An optical fiber communications link was installed for the purpose of evaluating the applicability of optical fiber technology to the distribution of frequency and timing reference signals. It incorporated a 1.5km length of optical fiber cable containing two multimode optical fibers. The two fibers were welded together at one end of the cable to attain a path length of 3km. Preliminary measurements made on this link, including Allan variance and power spectral density of phase noise are reported.
The technical communication practices of Russian and U.S. aerospace engineers and scientists
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Keene, Michael L.; Flammia, Madelyn; Kennedy, John M.
1993-01-01
As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communication practices of Russian and U.S. aerospace engineers and scientists. Both studies had the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communication to their professions; second, to determine the use and production of technical communication by aerospace engineers and scientists; third, to seek their views about the appropriate content of the undergraduate course in technical communication; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line databases; and fifth, to determine the use and importance of computer and information technology to them. A self administered questionnaire was distributed to Russian aerospace engineers and scientists at the Central Aero-Hydrodynamic Institute (TsAGI) and to their U.S. counterparts at the NASA Ames Research Center and the NASA Langley Research Center. The completion rates for the Russian and U.S. surveys were 64 and 61 percent, respectively. Responses of the Russian and U.S. participants to selected questions are presented in this paper.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.
1993-01-01
As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Project, two studies were conducted that investigated the technical communications practices of Russian and U.S. aerospace engineers and scientists. Both studies have the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their views about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line data bases; and fifth, to determine the use and importance of computer and information technology to them. A self-administered questionnaire was distributed to aerospace engineers and scientists at the Central Aero-Hydrodynamic Institute (TsAGI), NASA ARC, and NASA LaRC. The completion rates for the Russian and U.S. surveys were 64 and 61 percent, respectively. The responses of the Russian and U.S. participants, to selected questions, are presented in this report.
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.; Elazar, David; Kennedy, John M.
1991-01-01
As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two pilot studies were conducted that investigated the technical communications practices of Israeli and U.S. aerospace engineers and scientists. Both studies had the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communications to their profession; second, to determine the use and production of technical communications by aerospace engineers and scientists; third, to seek their view about the appropriate content of an undergraduate course in technical communications; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line databases; and fifth, to determine the use and importance of computer and information technology to them. A self-administered questionnaire was mailed to randomly selected U.S. aerospace engineers and scientists who are working in cryogenics, adaptive walls, and magnetic suspension. A slightly modified version was sent to Israeli aerospace engineers and scientists working at Israel Aircraft Industries, LTD. Responses of the Israeli and U.S. aerospace engineers and scientists to selected questions are presented in this paper.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Barclay, Rebecca O.; Keene, Michael L.; Flammia, Madelyn; Kennedy, John M.
1993-01-01
As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communication practices of Russian and U.S. aerospace engineers and scientists. Both studies had the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communication to their professions; second, to determine the use and production of technical communication by aerospace engineers and scientists; third, to seek their views about the appropriate content of the undergraduate course in technical communication; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line databases; and fifth, to determine the use and importance of computer and information technology to them. A self administered questionnaire was distributed to Russian aerospace engineers and scientists at the Central Aero-Hydrodynamic Institute (TsAGI) and to their U.S. counterparts at the NASA Ames Research Center and the NASA Langley Research Center. The completion rates for the Russian and U.S. surveys were 64 and 61 percent, respectively. Responses of the Russian and U.S. participants to selected questions are presented in this paper.
All-fiber hybrid photon-plasmon circuits: integrating nanowire plasmonics with fiber optics.
Li, Xiyuan; Li, Wei; Guo, Xin; Lou, Jingyi; Tong, Limin
2013-07-01
We demonstrate all-fiber hybrid photon-plasmon circuits by integrating Ag nanowires with optical fibers. Relying on near-field coupling, we realize a photon-to-plasmon conversion efficiency up to 92% in a fiber-based nanowire plasmonic probe. Around optical communication band, we assemble an all-fiber resonator and a Mach-Zehnder interferometer (MZI) with Q-factor of 6 × 10(6) and extinction ratio up to 30 dB, respectively. Using the MZI, we demonstrate fiber-compatible plasmonic sensing with high sensitivity and low optical power.
Basic Writing Concepts for Scientists and Engineers.
ERIC Educational Resources Information Center
Mitchell, John H.
1980-01-01
Notes the differences between poetry and technical communication. Charges English teacher/humanists with confusing students about emotional writing, style, and effective technical communication. Offers five concepts that technical writing teachers can use to place "style" on a rational basis and to make students understand the true purposes of…
White matter fiber tracking computation based on diffusion tensor imaging for clinical applications.
Dellani, Paulo R; Glaser, Martin; Wille, Paulo R; Vucurevic, Goran; Stadie, Axel; Bauermann, Thomas; Tropine, Andrei; Perneczky, Axel; von Wangenheim, Aldo; Stoeter, Peter
2007-03-01
Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiological institutions. Images combining anatomical information and the localization of different fiber tract trajectories can be encoded and exported in DICOM and Analyze formats, which are valuable resources in the clinical applications of this method. Fiber tracking was implemented based on existing line propagation algorithms, but it includes a heuristic for fiber crossings in the case of disk-shaped diffusion tensors. We successfully performed fiber tracking on MR-DTI data sets from 26 patients with different types of brain lesions affecting the corticospinal tracts. In all cases, the trajectories of the central spinal tract (pyramidal tract) were reconstructed and could be applied at the planning phase of the surgery as well as in intraoperative neuronavigation.
Undersea fiber optic technology for the offshore community
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mariano, J.J.
The explosive growth in demand for global communications has been met by a rapid evolution in the undersea fiber-optic technology, which in just a few years has become the predominant method of communication across the world`s oceans and seas. As the scope of applications has become broader, the technology has become more diverse, and now comprises a range of products capable of providing economical, reliable service in any subsea environment, from ocean depths to coastal lagoons. In this paper, the authors discuss how undersea lightwave technology is being applied to meet the communication and production control needs of the offshoremore » oil and gas industry. They discuss the trends and technology developments that are changing the economics of undersea fiber-optic communication networks, as well as synergies in the offshore industry. They consider various applications for the industry and means of enhancing the profitability of platform operations through reduced downtime, reduced operating cost, and enhanced safety. Finally, they discuss extensions to exploratory drilling and land-based operations.« less
Experimental multiplexing of quantum key distribution with classical optical communication
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Liu-Jun; Chen, Luo-Kan; Ju, Lei
2015-02-23
We demonstrate the realization of quantum key distribution (QKD) when combined with classical optical communication, and synchronous signals within a single optical fiber. In the experiment, the classical communication sources use Fabry-Pérot (FP) lasers, which are implemented extensively in optical access networks. To perform QKD, multistage band-stop filtering techniques are developed, and a wavelength-division multiplexing scheme is designed for the multi-longitudinal-mode FP lasers. We have managed to maintain sufficient isolation among the quantum channel, the synchronous channel and the classical channels to guarantee good QKD performance. Finally, the quantum bit error rate remains below a level of 2% across themore » entire practical application range. The proposed multiplexing scheme can ensure low classical light loss, and enables QKD over fiber lengths of up to 45 km simultaneously when the fibers are populated with bidirectional FP laser communications. Our demonstration paves the way for application of QKD to current optical access networks, where FP lasers are widely used by the end users.« less
Fiber to the home: next generation network
NASA Astrophysics Data System (ADS)
Yang, Chengxin; Guo, Baoping
2006-07-01
Next generation networks capable of carrying converged telephone, television (TV), very high-speed internet, and very high-speed bi-directional data services (like video-on-demand (VOD), Game etc.) strategy for Fiber To The Home (FTTH) is presented. The potential market is analyzed. The barriers and some proper strategy are also discussed. Several technical problems like various powering methods, optical fiber cables, and different network architecture are discussed too.
Quad Charts in the Classroom to Reinforce Technical Communication Fundamentals
ERIC Educational Resources Information Center
Ford, Julie Dyke; Wei, Tie
2015-01-01
Quad charts are a genre frequently used in scientific and technical environments, yet little prior work has evaluated their potential for reinforcing technical communication fundamentals. This article provides background information about quad charts and notes the benefits of implementing quad charts in the classroom. In particular, introducing…
Progress in Scientific and Technical Communications, 1968 Annual Report.
ERIC Educational Resources Information Center
Federal Council for Science and Technology, Washington, DC. Committee on Scientific and Technical Information.
This sixth annual report describes progress achieved by the Federal Government in improving the communication of scientific and technical information to support and enhance national science and technology. Included in the report are details regarding the scientific and technical activities of individual Federal Agencies, such as the Atomic Energy…
A Profile of In-House Teachers of Technical Communication.
ERIC Educational Resources Information Center
Mazzatenta, Ernest
To develop a profile of inhouse, company teachers of technical communication, a six-page questionnaire was administered to technical writing teachers. Of the 52 respondents, 24 offered both formal inhouse courses and informal training while 22 conducted only formal courses. Titles, course outlines, and other survey comments revealed that many…
"You Will": Technology, Magic, and the Cultural Contexts of Technical Communication.
ERIC Educational Resources Information Center
Kitalong, Karla Saari
2000-01-01
Provides some background on the use of magical language in technical contexts, gives examples of magical discourse in technology advertisements and newsmagazine articles, and proposes a technical communication pedagogy of media analysis. Notes that the proposed pedagogy involves students conducting diagnostic critiques of media texts and affords…
In Pursuit of a Rewarding Career
ERIC Educational Resources Information Center
Murphy, Avon J.
2015-01-01
Avon Murphy has been a college professor, a technical communications program director, a government technical writer, a freelancer, a contract editor at Microsoft and other firms, and owner of Murphy Editing and Writing Services. An STC (Society for Technical Communication) Fellow, he was for 17 years book review editor for "Technical…
New Perspectives on the Technical Communication Internship: Professionalism in the Workplace
ERIC Educational Resources Information Center
Bourelle, Tiffany
2014-01-01
This article argues for developing linked courses in technical communication where the instructor facilitates a service-learning curriculum and then serves as faculty advisor within subsequent internships. In these linked courses, students write technical documents before moving into internships where they write similar documents. Specifically,…
An Overview of Clarkson's Technical Communications Program.
ERIC Educational Resources Information Center
Barkman, Patricia R.
The technical communications program at Clarkson College (New York) offers students 23 courses in subjects ranging from interpersonal behavior to engineering and scientific report writing to computer documentation and the development of technical manuals. With the help of an advisor, each student works out a course of study appropriate to his or…
The Role of Communication in the Professional Socialization Process.
ERIC Educational Resources Information Center
Barnett, George A.; Carson, David L.
To explore the professional socialization of technical writers and communicators, 98 professional technical communicators were administered a questionnaire identifying key concepts in the field. On seven occasions, professionals, teachers, and graduate students were asked to estimate how greatly these concepts, together with four additional terms…
ERIC Educational Resources Information Center
Kelly, James D.
This paper attempts to assess the influence of development communication theory on the planning and implementation of technical assistance projects in the Third World that utilize mass communication as an agent of change. Like political development theory, communication theory has often been applied in an ethnocentric manner in less developed…
Communicating to Influence Drug Development and Regulatory Decisions: A Tutorial
Mehrotra, S
2016-01-01
Pharmacometricians require three skills to be influential: technical, business (e.g., drug development), and soft skills (e.g., communication). Effective communication is required to translate technical and often complicated quantitative findings to interdisciplinary team members in order to influence drug development or regulatory decisions. In this tutorial, we highlight important aspects related to communicating pharmacometric analysis to influence decisions. PMID:27299706
PCS optical fibers for an automobile data bus
NASA Astrophysics Data System (ADS)
Clarkin, James P.; Timmerman, Richard J.; Stolte, Gary W.; Klein, Karl-Friedrich
2005-02-01
Optical fibers have been used for data communications in automobiles for several years. The fiber of choice thus far has been a plastic core/plastic clad optical fiber (POF) consisting of the plastic polymethylmethacrylate (PMMA). The POF fiber provides a low cost fiber with relatively easy termination. However, increasing demands regarding temperature performance, transmission losses and bandwidth have pushed the current limits of the POF fiber, and the automotive industry is now moving towards an optical fiber with a silica glass core/plastic clad (PCS). PCS optical fibers have been used successfully in industrial, medical, sensor, military and data communications systems for over two decades. The PCS fiber is now being adapted specifically for automotive use. In the following, the design criteria and design alternatives for the PCS as well as optical, thermal, and mechanical testing results for key automotive parameters are described. The fiber design tested was 200&mum synthetic silica core/230&mum fluoropolymer cladding/1510&mum nylon buffer. Key attributes such as 700 - 900 nm spectral attenuation, 125°C thermal soak, -40 to 125°C thermal cycling, bending losses, mechanical strength, termination capability, and cost are discussed and compared. Overall, a specifically designed PCS fiber is expected to be acceptable for the use in an automotive data bus, and will show improvement in optical transmission, temperature range and bandwidth. However, the final selection of buffer and jacket materials and properties will be most dependent on the selection of a reliable and economical termination method.
Seismic fiber optic multiplexed sensors for exploration and reservoir management
NASA Astrophysics Data System (ADS)
Houston, Mark H.
2000-12-01
Reliable downhole communications, control and sensor networks will dramatically improve oil reservoir management practices and will enable the construction of intelligent or smart-well completions. Fiber optic technology will play a key role in the implementation of these communication, control and sensing systems because of inherent advantages of power, weight and reliability over more conventional electronic-based systems. Field test data, acquired using an array of fiber optic seismic hydrophones within a steam-flood, heavy oil- production filed, showed a significant improvement (10X in this specific case) in subsurface resolution as compared to conventional surface seismic acquisition. These results demonstrate the viability of using multiplexed fiber optic sensors for exploration and reservoir management in 3D vertical seismic profiling (VSP) surveys and in permanent sensor arrays for 4D surveys.
Optical Communication: Its History and Recent Progress
NASA Astrophysics Data System (ADS)
Agrawal, Govind P.
This chapter begins with a brief history of optical communication before describing the main components of a modern optical communication system. Specific attention is paid to the development of low-loss optical fibers as they played an essential role after 1975. The evolution of fiber-optic communication systems is described through its six generations over a 40-year time period ranging from 1975 to 2015. The adoption of wavelength-division multiplexing (WDM) during the 1990s to meet the demand fueled by the advent of the Internet is discussed together with the bursting of the telecom bubble in 2000. Recent advances brought by digital coherent technology and space-division multiplexing are also described briefly.
NASA Astrophysics Data System (ADS)
Serpa-Imbett, C. M.; Marín-Alfonso, J.; Gómez-Santamaría, C.; Betancur-Agudelo, L.; Amaya-Fernández, F.
2013-12-01
Space division multiplexing in multicore fibers is one of the most promise technologies in order to support transmissions of next-generation peta-to-exaflop-scale supercomputers and mega data centers, owing to advantages in terms of costs and space saving of the new optical fibers with multiple cores. Additionally, multicore fibers allow photonic signal processing in optical communication systems, taking advantage of the mode coupling phenomena. In this work, we numerically have simulated an optical MIMO-OFDM (multiple-input multiple-output orthogonal frequency division multiplexing) by using the coded Alamouti to be transmitted through a twin-core fiber with low coupling. Furthermore, an optical OFDM is transmitted through a core of a singlemode fiber, using pilot-aided channel estimation. We compare the transmission performance in the twin-core fiber and in the singlemode fiber taking into account numerical results of the bit-error rate, considering linear propagation, and Gaussian noise through an optical fiber link. We carry out an optical fiber transmission of OFDM frames using 8 PSK and 16 QAM, with bit rates values of 130 Gb/s and 170 Gb/s, respectively. We obtain a penalty around 4 dB for the 8 PSK transmissions, after 100 km of linear fiber optic propagation for both singlemode and twin core fiber. We obtain a penalty around 6 dB for the 16 QAM transmissions, with linear propagation after 100 km of optical fiber. The transmission in a two-core fiber by using Alamouti coded OFDM-MIMO exhibits a better performance, offering a good alternative in the mitigation of fiber impairments, allowing to expand Alamouti coded in multichannel systems spatially multiplexed in multicore fibers.
Choi, Nam-Hong; Son, Kyung-Mo; Victoroff, Brian N
2008-09-01
This technical note describes a new arthroscopic technique to repair a tear of posterior root of the medial meniscus. Cartilage at the insertion area of the posterior horn of the medial meniscus (PHMM) was removed using a curved curette inserted through an anteromedial portal. A metal anchor loaded with two FiberWires (Arthrex, Naples, FL) was placed at the insertion area of the PHMM through a high posteromedial portal. A PDS suture was passed the PHMM by curved suture hook through the anteromedial portal. Two limbs of the PDS were then used to pass two limbs of the FiberWire through the meniscus. The same procedure was repeated for the second FiberWire suture. The sutures were tied, achieving secure fixation of the posterior meniscal root at the anatomic insertion.
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.; Tan, Axel S. T.; Kennedy, John M.
1993-01-01
As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. A self-administered questionnaire was distributed to aerospace engineers and scientists at the National Aerospace Laboratory (The Netherlands), and NASA ARC (U.S.), and NASA LaRC (U.S.). This paper presents responses of the Dutch and U.S. participants to selected questions concerning four of the seven project objectives: determining the importance of technical communications to aerospace engineering professionals, investigating the production of technical communications, examining the use and importance of computer and information technology, and exploring the use of electronic networks.
Lignin carbon fiber: The path for quality
Yuan, Joshua S.; Li, Qiang; Ragauskas, Arthur J.
2017-03-01
Lignin represents an abundant biopolymer and a major waste from lignocellulosic processing plants, yet the utilization of lignin for fungible products remains one of the most challenging technical barriers for pulp mills and the modern biorefinery industry. In recent decades, lignin has been sought after as a precursor polymer for carbon fiber due to the high carbon content (up to 60%). Furthermore lignin carbon fiber is expected to be compatible with the market size of the pulp and paper industry and may have transformative impact on petroleum-based carbon fiber.
Cable tunnel fire experiment study based on linear optical fiber fire detectors
NASA Astrophysics Data System (ADS)
Fan, Dian; Ding, Hongjun
2013-09-01
Aiming at exiting linear temperature fire detection technology including temperature sensing cable, fiber Raman scattering, fiber Bragg grating, this paper establish an experimental platform in cable tunnel, set two different experimental scenes of the fire and record temperature variation and fire detector response time in the processing of fire simulation. Since a small amount of thermal radiation and no flame for the beginning of the small-scale fire, only directly contacting heat detectors can make alarm response and the rest of other non- contact detectors are unable to respond. In large-scale fire, the alarm response time of the fiber Raman temperature sensing fire detector and fiber Bragg grating temperature sensing fire detector is about 30 seconds, and depending on the thermocouples' record the temperature over the fire is less than 35° in first 60 seconds of large-scale fire, while the temperature rising is more than 5°/min within the range of +/- 3m. According to the technical characteristics of the three detectors, the engineering suitability of the typical linear heat detectors in cable tunnels early fire detection is analyzed, which provide technical support for the preparation of norms.
Utilization of Infrared Fiber Optic in the Automotive Industry
NASA Technical Reports Server (NTRS)
Tucker, Dennis S.; Brantley, Lott W. (Technical Monitor)
2001-01-01
Fiber optics are finding a place in the automotive industry. Illumination is the primary application today. Soon, however, fiber optics will be used for data communications and sensing applications. Silica fiber optics and plastic fibers are sufficient for illumination and communication applications however, sensing applications involving high temperature measurement and remote gas analysis would benefit from the use of infrared fiber optics. Chalcogonide and heavy metal fluoride glass optical fibers are two good candidates for these applications. Heavy metal fluoride optical fibers are being investigated by NASA for applications requiring transmission in the infrared portion of the electromagnetic spectrum. Zirconium-Barium-Lanthanum-Aluminum-Sodium-Fluoride (ZBLAN) is one such material which has been investigated. This material has a theoretical attenuation coefficient 100 times lower than that of silica and transmits into the mid-IR. However, the measured attenuation coefficient is higher than silica due to impurities and crystallization. Impurities can be taken care of by utilizing cleaner experimental protocol. It has been found that crystallization can be suppressed by processing in reduced gravity. Fibers processed in reduced gravity on the KC135 reduced gravity aircraft were found to be free of crystals while those processed on the ground were found to have crystals. These results will be presented along with plans for producing continuous lengths of ZBLAN optical fiber on board the International Space Station.
The Elusiveness of Workplace Culture: Response to "Technical Communication: The Cultural Context."
ERIC Educational Resources Information Center
Parsons, Gerald M.
1987-01-01
Responds to C. Lipson's article on the cultural context of technical communication by criticizing her lack of definition of the term "corporate culture," and suggesting that analyzing corporations as cultures is naive, simplistic, and would probably have little value for students of business communication. (SKC)
Aristotelian Rhetorical Theory as a Framework for Teaching Scientific and Technical Communication.
ERIC Educational Resources Information Center
Newman, Sara
1999-01-01
Describes an upper level rhetorical theory course for Scientific and Technical Communication majors (developed and taught by the author) that is grounded in Aristotle's "On Rhetoric" and in his understanding that effective communication is a systematic "tekhne"/art. Describes how the course uses Aristotle's work as a…
ERIC Educational Resources Information Center
Palmer, Zsuzsanna Bacsa
2013-01-01
The effects of globalization on communication products and processes have resulted in document features and interactional practices that are sometimes difficult to describe within current theoretical frameworks of inter/transcultural technical communication. Although it has been recognized in our field that the old theoretical frameworks and…
Satellite-Based Quantum Communications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, Richard J; Nordholt, Jane E; McCabe, Kevin P
2010-09-20
Single-photon quantum communications (QC) offers the attractive feature of 'future proof', forward security rooted in the laws of quantum physics. Ground based quantum key distribution (QKD) experiments in optical fiber have attained transmission ranges in excess of 200km, but for larger distances we proposed a methodology for satellite-based QC. Over the past decade we have devised solutions to the technical challenges to satellite-to-ground QC, and we now have a clear concept for how space-based QC could be performed and potentially utilized within a trusted QKD network architecture. Functioning as a trusted QKD node, a QC satellite ('QC-sat') could deliver secretmore » keys to the key stores of ground-based trusted QKD network nodes, to each of which multiple users are connected by optical fiber or free-space QC. A QC-sat could thereby extend quantum-secured connectivity to geographically disjoint domains, separated by continental or inter-continental distances. In this paper we describe our system concept that makes QC feasible with low-earth orbit (LEO) QC-sats (200-km-2,000-km altitude orbits), and the results of link modeling of expected performance. Using the architecture that we have developed, LEO satellite-to-ground QKD will be feasible with secret bit yields of several hundred 256-bit AES keys per contact. With multiple ground sites separated by {approx} 100km, mitigation of cloudiness over any single ground site would be possible, potentially allowing multiple contact opportunities each day. The essential next step is an experimental QC-sat. A number of LEO-platforms would be suitable, ranging from a dedicated, three-axis stabilized small satellite, to a secondary experiment on an imaging satellite. to the ISS. With one or more QC-sats, low-latency quantum-secured communications could then be provided to ground-based users on a global scale. Air-to-ground QC would also be possible.« less
DOT National Transportation Integrated Search
1995-11-01
Fiber-optic cable is recognized as one of the most efficient and reliable mediums of telecommunication available today. The last decade has witnessed an enormous growth in this form of telecommunication. However, one of its major disadvantages is tha...
The fiber-optic high-speed data bus for a new generation of military aircraft
NASA Astrophysics Data System (ADS)
Uhlhorn, Roger W.
1991-02-01
The avionic suite for the next generation of military aircraft is being designed with component and module commonality in mind in order to control recurring costs and capitalize on economy of scale. The backbone of the suite fashioned out of these modular building blocks is the fiber-optic bit-serial time-division multiplexed high-speed data bus (HSDB), operating at 50 Mb/s, which provides command and control communications among most of the aircraft subsystems and can be used to provide communications for a fly-by-light flight-control system or for the block transfer of data between mass memories and data processors. The fiber-optic HSDB is examined from the top down, beginning with an overview of the evolution of avionic architectures. A review is given of the standardization activity associated with development of the network, the protocols chosen to implement the desired communication functions, configuration options, and the fiber-optic components used in the bus interfaces or other active nodes of the network. It is believed that the utility of the bus extends beyond aircraft to spacecraft, ships, and land vehicles.
1984-06-20
AD-A162 ±88 FEASIBILITY STUDY FOR A COMPUTERIZED SERIALS CONTROL 1/1 SYSTEM IN THE DEFENS (U) DEFENSE COMMUNICATIONS AGENCY WASHINGTON DC TECHNICAL...NATIONAL BUREAU OF STANDARDS- 1963-A 0FEASIBILITY STUDY FOR A COMPUTERIZED SERIALS CONTROL SYSTEM IN THE DEFENSE COMMUNICATIONS 0AGENCY TECHNICAL AND...ABSTRACT 21. ABSTRACT SECURITY CLASSIFICATION UNCLASSIFIED/UNLIMITED R1 SAME AS RPT. 0 DTIC USERS 0 UNCLASSIFIED 22&. NAME OF RESPONSIBLE INDIVIDUAL 22b
Exposing Hidden Relations: Storytelling, Pedagogy, and the Study of Policy
ERIC Educational Resources Information Center
Moore, Kristen
2013-01-01
Within a Technical Communication classroom, policywork has been used to teach students the vital discursive and conceptual skills valued by technical fields. However, given the move of technical communicators into the public sphere, these skills can and should be expanded to include diverse practices and modes of thought. As such, this article…
Computer Programs for Technical Communicators: The Compelling Curriculum. Working Draft.
ERIC Educational Resources Information Center
Selfe, Cynthia L.; Wahlstrom, Billie J.
A series of computer programs have been developed at Michigan Technological University for use with technical writing and technical communications classes. The first type of program in the series, CURIE II, includes process-based modules, each of which corresponds to one of the following assignments: memoranda, resumes, feasibility reports,…
High bandwidth specialty optical fibers for data communications
NASA Astrophysics Data System (ADS)
Li, Jie; Sun, Xiaoguang
2008-11-01
Perhaps the most common specialty optical fiber is HCS hard polymer clad silica fiber. It was invented almost 30 years ago for transmitting laser light to initiate explosives in mining industry and later adapted to be used in a variety of new applications, such as data communications. The most typical HCS fiber typically consists of a 200 μm pure silica glass core, a thin coating of low refractive index hard polymer as the cladding, and an ETFE buffer. This design enables the "crimp-and-cleave" technique of terminating and connectorizing fibers quickly and reliably. Its greater glass diameter also renders greater robustness allowing the fiber to endure greater forces during installation. Due to its larger core size and high numerical aperture (NA), the fiber can be used with a plastic connector and low cost LED transmitter that can greatly reduce the system cost. It can also be used at higher temperature and humidity conditions than standard optical fibers coated with telecommunications grade acrylate material. As applications evolve and require greater bandwidth and/or performance over a greater distance, the challenge now is to develop specialty optical fibers with significantly greater bandwidth-length product while maintaining all other characteristics critical to their ease of use and performance. As a response to the demand, two new fiber types have been designed and developed as higher bandwidth versions of the original HCS fiber. In this paper, we will discuss some of the main design requirements for the fibers, describe in detail the two designs, and present the results of fiber performance.
NASA Astrophysics Data System (ADS)
Ortyl, Nicholas E.
2005-11-01
The application of MEMS and nanotechnology (MNT) to the field of structural health monitoring (SHM) is a fairly recent development. The recent change in this focus for MNT has been driven by the need to expand the applications for much of the technologies that were developed in the late 1990s. In addition, many companies desire to expand beyond their target high volume market segments of automotive, wireless communications, and computer peripherals, since these market segments were not as lucrative as first predicted. Most of the aerospace structural health monitoring developmental activity has been sponsored by agencies of the U.S. Government, which serves to pace the examination of these newer technologies to some degree. With that said, efforts are underway by companies such as Acellent Technologies and Blue Road Research to explore various MNT structural health monitoring approaches. The MNT under test include embedded piezoelectric sensors, MEMS accelerometers, time domain region sensors, and topical and embedded single and multi-axis fiber optic Bragg grating sensors. The promise of MNT for the SHM market segment is very enticing. The many wireless communication developments and miniaturization developments of the past five years is very attractive to the SHM community, especially those that are able to reduce the cost and complexity of integration. The main challenge for the community is one of selective integration. That is, certain pieces may be appropriate for SHM systems and certain pieces may not be. The better companies will chose wisely and put forth an approach that can be seamlessly integrated into the larger structure. For over a decade, Blue Road Research has been developing technologies aimed at structural health monitoring of both composite and non-composite parts, through the use of single and multiaxis fiber optic Bragg grating sensors. These sensors are 80 to 120 microns in diameter making them smaller than the diameter of a human hair. Multiaxis fiber optic sensors are able to measure pressure, temperature, axial and transverse strain, chemical properties, corrosion, as well as transverse strain gradients. This technology is easily embedded in between the various layers of the composite structure, during manufacture, without compromising the structural integrity, in order to verify manufacturing parameters during the cure cycle and well as monitor the on-going condition of the composite structure throughout its life time. This paper reviews some of the technical work that has been accomplished during the past two years; specifically the embedding of fiber optic sensors into various composite structures in order to be able to conduct in situ non-destructive evaluation of the curing process and the service life of the component. The fiber optic technology has been developed to the point that it is at a TRL of 6.
Shuttle ku-band communications/radar technical concepts
NASA Technical Reports Server (NTRS)
Griffin, J. W.; Kelley, J. S.; Steiner, A. W.; Vang, H. A.; Zrubek, W. E.; Huth, G. K.
1985-01-01
Technical data on the Shuttle Orbiter K sub u-band communications/radar system are presented. The more challenging aspects of the system design and development are emphasized. The technical problems encountered and the advancements made in solving them are discussed. The radar functions are presented first. Requirements and design/implementation approaches are discussed. Advanced features are explained, including Doppler measurement, frequency diversity, multiple pulse repetition frequencies and pulse widths, and multiple modes. The communications functions that are presented include advances made because of the requirements for multiple communications modes. Spread spectrum, quadrature phase shift keying (QPSK), variable bit rates, and other advanced techniques are discussed. Performance results and conclusions reached are outlined.
Radiation hardening commercial off-the-shelf erbium doped fibers by optimal photo-annealing source
NASA Astrophysics Data System (ADS)
Peng, Tz-Shiuan; Liu, Ren-Young; Lin, Yen-Chih; Mao, Ming-Hua; Wang, Lon A.
2017-09-01
Erbium doped fibers (EDFs) based devices are widely employed in space for optical communication [1], remote sensing [2], and navigation applications, e.g. interferometric fiber optic gyroscope (IFOG). However, the EDF suffers severely radiation induced attenuation (RIA) in radiation environments, e.g. space applications and nuclear reactors [3].
An accelerated gamma irradiation test of low dose rate for a single mode fiber
NASA Astrophysics Data System (ADS)
Chiou, Chung-An; Peng, Tz-Shiuan; Liu, Ren-Young
2017-09-01
Conventional single mode fiber (SMF), due to its electromagnetic interference immunity, light weight, physical flexibility and broad bandwidth for data transmission, has been well employed in space, such as optical communication [1], structural health monitoring of spacecraft [2], and attitude determining applications, e.g. interferometric fiber optic gyroscope (IFOG).
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-30
..., as amended, 19 U.S.C. 1337, on behalf of Avago Technologies Fiber IP (Singapore) Pte. Ltd. of Singapore; Avago Technologies General IP (Singapore) Pte. Ltd. of Singapore; and Avago Technologies U.S. Inc... Technologies Fiber IP, (Singapore) Pte. Ltd., 1 Yishun Avenue 7, Singapore 768923. Avago Technologies General...
Distribution automation applications of fiber optics
NASA Technical Reports Server (NTRS)
Kirkham, Harold; Johnston, A.; Friend, H.
1989-01-01
Motivations for interest and research in distribution automation are discussed. The communication requirements of distribution automation are examined and shown to exceed the capabilities of power line carrier, radio, and telephone systems. A fiber optic based communication system is described that is co-located with the distribution system and that could satisfy the data rate and reliability requirements. A cost comparison shows that it could be constructed at a cost that is similar to that of a power line carrier system. The requirements for fiber optic sensors for distribution automation are discussed. The design of a data link suitable for optically-powered electronic sensing is presented. Empirical results are given. A modeling technique that was used to understand the reflections of guided light from a variety of surfaces is described. An optical position-indicator design is discussed. Systems aspects of distribution automation are discussed, in particular, the lack of interface, communications, and data standards. The economics of distribution automation are examined.
Robust bidirectional links for photonic quantum networks
Xu, Jin-Shi; Yung, Man-Hong; Xu, Xiao-Ye; Tang, Jian-Shun; Li, Chuan-Feng; Guo, Guang-Can
2016-01-01
Optical fibers are widely used as one of the main tools for transmitting not only classical but also quantum information. We propose and report an experimental realization of a promising method for creating robust bidirectional quantum communication links through paired optical polarization-maintaining fibers. Many limitations of existing protocols can be avoided with the proposed method. In particular, the path and polarization degrees of freedom are combined to deterministically create a photonic decoherence-free subspace without the need for any ancillary photon. This method is input state–independent, robust against dephasing noise, postselection-free, and applicable bidirectionally. To rigorously quantify the amount of quantum information transferred, the optical fibers are analyzed with the tools developed in quantum communication theory. These results not only suggest a practical means for protecting quantum information sent through optical quantum networks but also potentially provide a new physical platform for enriching the structure of the quantum communication theory. PMID:26824069
NASA Astrophysics Data System (ADS)
Han, Ya; Liu, Yan-Ge; Wang, Zhi; Huang, Wei; Chen, Lei; Zhang, Hong-Wei; Yang, Kang
2018-01-01
Mode-division multiplexing (MDM) is a promising technology for increasing the data-carrying capacity of a single few-mode optical fiber. The flexible mode manipulation would be highly desired in a robust MDM network. Recently, orbital angular momentum (OAM) modes have received wide attention as a new spatial mode basis. In this paper, we firstly proposed a long period fiber grating (LPFG) system to realize mode conversions between the higher order LP core modes in four-mode fiber. Based on the proposed system, we, for the first time, demonstrate the controllable all-fiber generation and conversion of the higher order LP core modes to the first and second order circularly polarized OAM beams with all the combinations of spin and OAM. Therefore, the proposed LPFG system can be potentially used as a controllable higher order OAM beam switch and a physical layer of the translating protocol from the conventional LP modes communication to the OAM modes communication in the future mode carrier telecommunication system and light calculation protocols.
Integrating quantum key distribution with classical communications in backbone fiber network.
Mao, Yingqiu; Wang, Bi-Xiao; Zhao, Chunxu; Wang, Guangquan; Wang, Ruichun; Wang, Honghai; Zhou, Fei; Nie, Jimin; Chen, Qing; Zhao, Yong; Zhang, Qiang; Zhang, Jun; Chen, Teng-Yun; Pan, Jian-Wei
2018-03-05
Quantum key distribution (QKD) provides information-theoretic security based on the laws of quantum mechanics. The desire to reduce costs and increase robustness in real-world applications has motivated the study of coexistence between QKD and intense classical data traffic in a single fiber. Previous works on coexistence in metropolitan areas have used wavelength-division multiplexing, however, coexistence in backbone fiber networks remains a great experimental challenge, as Tbps data of up to 20 dBm optical power is transferred, and much more noise is generated for QKD. Here we present for the first time, to the best of our knowledge, the integration of QKD with a commercial backbone network of 3.6 Tbps classical data at 21 dBm launch power over 66 km fiber. With 20 GHz pass-band filtering and large effective core area fibers, real-time secure key rates can reach 4.5 kbps and 5.1 kbps for co-propagation and counter-propagation at the maximum launch power, respectively. This demonstrates feasibility and represents an important step towards building a quantum network that coexists with the current backbone fiber infrastructure of classical communications.
Space Flight Applications of Optical Fiber; 30 Years of Space Flight Success
NASA Technical Reports Server (NTRS)
Ott, Melanie N.
2010-01-01
For over thirty years NASA has had success with space flight missions that utilize optical fiber component technology. One of the early environmental characterization experiments that included optical fiber was launched as the Long Duration Exposure Facility in 1978. Since then, multiple missions have launched with optical fiber components that functioned as expected, without failure throughout the mission life. The use of optical fiber in NASA space flight communications links and exploration and science instrumentation is reviewed.
Technical Communication Competence and Projected Teacher Success.
ERIC Educational Resources Information Center
Powers, William G.; Lowry, David N.
Technical Communication Competence (TCC)is the competence involved in communicating mental images to others in such a manner as to result in their constructing comparable mental images, a process similar to the primary task demanded of teachers at all levels. In a study designed to discover the extent to which a positive relationship existed…
ERIC Educational Resources Information Center
Cardenas, Diana L.
2012-01-01
Community-based projects immerse technical writing students in intercultural communication, addressing local needs and shaping documents in human terms. Students at a South Texas university work to establish communication with clients in a city-county health department to create effective documents and disseminate family health legislation. To…
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.; Tan, Axel S. T.; Kennedy, John M.
1993-01-01
As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. A self-administered questionnaire was distributed to aerospace engineers and scientists at the National Aerospace Laboratory (The Netherlands), and NASA Ames Research Center (U.S.), and the NASA Langley Research Center (U.S.). This paper presents responses of the Dutch and U.S. participants to selected questions about four of the seven project objectives: determining the importance of technical communications to aerospace engineering professionals, investigating the production of technical communications, examining the use and importance of computer and information technology, and exploring the use of electronic networks.
Technical change in forest sector models: the global forest products model approach
Joseph Buongiorno; Sushuai Zhu
2015-01-01
Technical change is developing rapidly in some parts of the forest sector, especially in the pulp and paper industry where wood fiber is being substituted by waste paper. In forest sector models, the processing of wood and other input into products is frequently represented by activity analysis (inputâoutput). In this context, technical change translates in changes...
Satellite owners move to offset telephony losses to optical fiber
NASA Astrophysics Data System (ADS)
Lowndes, J. C.
1985-02-01
Preparations are made to exploit the advantages of communications satellites for distributing messages among many locations at once. By providing such services, it would be possible to offset losses in telephone market share, which are expected during the last half of the decade because of optical fiber competition. If the ventures in point-to-multipoint communications are successful, satellites can be employed to extend the full range of telecommunications services to many ground stations in suburban, rural, and even remote areas. In connection with current technological developments, it appears that optical fiber or digital microwave will replace satellites later in this decade on many long-haul routes with heavy traffic. An American telephone company plans to construct 21,000 miles of optical fiber facilities connecting U.S. cities and spanning the Atlantic and Pacific by the end of the decade.
ERIC Educational Resources Information Center
Sullivan, Patricia; Moore, Kristen
2013-01-01
This article brings together the communication needs and positioning of women in technical areas, and asks "how can technical communication classes contribute to the mentoring of young women engineers at a time when many of those women want to be identified as engineers instead of being spotlighted as women in engineering?" Incorporating…
ERIC Educational Resources Information Center
Matveeva, Natalia
2008-01-01
This research article reports the results of an online survey distributed among technical writing instructors in 2006. The survey aimed to examine how we teach intercultural communication in basic technical writing courses: our current practices and methods. The article discusses three major challenges that instructors may face when teaching about…
NASA Technical Reports Server (NTRS)
Bates, Harry
1990-01-01
A number of optical communication lines are now in use at the Kennedy Space Center (KSC) for the transmission of voice, computer data, and video signals. Presently, all of these channels utilize a single carrier wavelength centered near 1300 nm. The theoretical bandwidth of the fiber far exceeds the utilized capacity. Yet, practical considerations limit the usable bandwidth. The fibers have the capability of transmitting a multiplicity of signals simultaneously in each of two separate bands (1300 and 1550 nm). Thus, in principle, the number of transmission channels can be increased without installing new cable if some means of wavelength division multiplexing (WDM) can be utilized. The main goal of these experiments was to demonstrate that a factor of 2 increase in bandwidth utilization can share the same fiber in both a unidirectional configuration and a bidirectional mode of operation. Both signal and multimode fiber are installed at KSC. The great majority is multimode; therefore, this effort concentrated on multimode systems.
Fiber Based Optical Amplifier for High Energy Laser Pulses Final Report CRADA No. TC02100.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Messerly, M.; Cunningham, P.
This was a collaborative effort between Lawrence Livermore National Security, LLC (formerly The Regents of the University of California)/Lawrence Livermore National Laboratory (LLNL), and The Boeing Company to develop an optical fiber-based laser amplifier capable of producing and sustaining very high-energy, nanosecond-scale optical pulses. The overall technical objective of this CRADA was to research, design, and develop an optical fiber-based amplifier that would meet specific metrics.
NASA Astrophysics Data System (ADS)
Dikmelik, Yamac
High-speed free-space optical communication systems have recently utilized components that have been developed for fiber-optic communication systems. The received laser beam in such a system must be coupled into a single-mode fiber at the input of a commercially available receiver module or a wavelength division demultiplexer. However, one effect of propagation through atmospheric turbulence is that the spatial coherence of a laser beam is degraded and the percentage of the available power that can be coupled into the single-mode fiber is limited. This dissertation presents a numerical evaluation of fiber coupling efficiency for laser light distorted by atmospheric turbulence. The results for weak fluctuation conditions provide the level of coupling efficiency that can be expected for a given turbulence strength. In addition, the results show that the link distance must be limited to 400 m under moderate turbulence conditions if the link budget requires a coupling efficiency of 0.1. We also investigate the use of a coherent fiber array as a receiver structure to improve the fiber coupling efficiency of a free-space optical communication system. Our numerical results show that a coherent fiber array that consists of seven subapertures would increase fiber coupling efficiency by a significant amount for representative turbulence conditions and link distances. The use of photo-emf detectors as elements of a wavefront sensor for an adaptive optics system is also considered as an alternative method of reducing the effects of turbulence on a free-space optical communication system. Dember and photo-emf currents are investigated in silicon photoconductive detectors both theoretically and experimentally. Our results show that Dember photocurrents dominate the response of high-purity silicon samples with top surface electrodes to a moving interference pattern. The use of surface electrodes leads to shadowed regions beneath the electrodes and Dember photocurrents appear under short circuit conditions. The dependence of the Dember photocurrent on the number and the position of the interference fringes between the electrodes is described by a single charge carrier model of the Dember effect under plane-wave illumination. The predicted Dember photocurrent is in good qualitative agreement with experimental results but the quantitative agreement is not very accurate. The latter can be improved by using a more complicated two-sign charge carrier model for the Dember photocurrent and by taking into account the Gaussian spatial profile of the illuminating beams. We also show theoretically that the photo-emf effect in silicon is weak compared to other semiconductors because of its relatively high intrinsic conductivity.
Evaluating the effectiveness of case method instruction in technical communication
NASA Technical Reports Server (NTRS)
Feinberg, S. G.
1981-01-01
The effectiveness of the case method as an instructional technique in improving technical writing was evaluated. The development of a self-report instrument that attempts to measure changes in attitude toward technical communication and the presentation results change are the purpose of this paper. Standards for developing a case set forth by Goldstein and Couture, were used to design an evaluation instrument to measure the effect instruction on student attitude toward technical communication. This self-report instrument is based on model developed and tested by Daly and Miller who studied writer attitude and apprehension toward writing. It was the most important objective of any evaluation is to provide information for improving the program.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Brian P.; Sadlier, Ronald J.; Humble, Travis S.
Adopting quantum communication to modern networking requires transmitting quantum information through a fiber-based infrastructure. In this paper, we report the first demonstration of superdense coding over optical fiber links, taking advantage of a complete Bell-state measurement enabled by time-polarization hyperentanglement, linear optics, and common single-photon detectors. Finally, we demonstrate the highest single-qubit channel capacity to date utilizing linear optics, 1.665 ± 0.018, and we provide a full experimental implementation of a hybrid, quantum-classical communication protocol for image transfer.
Ultra-widely tunable long-period holey-fiber grating by the use of mechanical pressure.
Ceballos-Herrera, D E; Torres-Gómez, I; Martínez-Ríos, A; Anzueto-Sánchez, G; Alvarez-Chávez, J A; Selvas-Aguilar, R; Sánchez-Mondragón, J J
2007-01-20
We report an ultra-widely tunable long-period holey-fiber grating, which combines the wide-range single-mode behavior and transverse strain sensitivity of the holey fibers with the advantages of mechanically induced long-period fiber gratings. We obtain a versatile widely tunable long-period holey-fiber grating with attractive transmission spectral characteristics for optical communications, fiber-based amplifiers, and lasers. The mechanically induced long-period holey-fiber grating shows a continuous tuning range over 500 nm, more than 12 dB depth notches with less than 0.75 dB out-of-band losses, and bandwidth control from 10 to 40 nm.
1998-02-05
This graph depicts the increased signal quality possible with optical fibers made from ZBLAN, a family of heavy-metal fluoride glasses (fluorine combined zirconium, barium, lanthanum, aluminum, and sodium) as compared to silica fibers. NASA is conducting research on pulling ZBLAN fibers in the low-g environment of space to prevent crystallization that limits ZBLAN's usefulness in optical fiber-based communications. In the graph, a line closer to the black theoretical maximum line is better. Photo credit: NASA/Marshall Space Flight Center
NASA Astrophysics Data System (ADS)
Li, Xiang; Luo, Ming; Qiu, Ying; Alphones, Arokiaswami; Zhong, Wen-De; Yu, Changyuan; Yang, Qi
2018-02-01
In this paper, channel equalization techniques for coherent optical fiber transmission systems based on independent component analysis (ICA) are reviewed. The principle of ICA for blind source separation is introduced. The ICA based channel equalization after both single-mode fiber and few-mode fiber transmission for single-carrier and orthogonal frequency division multiplexing (OFDM) modulation formats are investigated, respectively. The performance comparisons with conventional channel equalization techniques are discussed.
Characteristics of holey fibers fabricated at different drawing speeds
NASA Astrophysics Data System (ADS)
Seraji, Faramarz E.; Rashidi, Mahnaz; Karimi, Maryam
2007-03-01
The effects of high drawing speeds on parameters of holey fibers are presented. A holey fiber preform structure was made by using tube-in-tube method and was drawn at high speeds with an aim of mass production to meet the demand of next generation communication systems. Transmission parameters such as numerical aperture and normalized frequency of the fabricated holey fibers have been measured and compared with theoretical values based on effective index method. Although the fabricated holey fibers were not of high quality, the analyses of the parameters have shown promising outlook for fabrication of such fibers.
Real-time In-Flight Strain and Deflection Monitoring with Fiber Optic Sensors
NASA Technical Reports Server (NTRS)
Richards, Lance; Parker, Allen R.; Ko, William L.; Piazza, Anthony
2008-01-01
This viewgraph presentation reviews Dryden's efforts to develop in-flight monitoring based on Fiber Optics. One of the motivating factors for this development was the breakup of the Helios aircraft. On Ikhana the use of fiber optics for wing shape sensing is being developed. They are being used to flight validate fiber optic sensor measurements and real-time wing shape sensing predictions on NASA's Ikhana vehicle; validate fiber optic mathematical models and design tools; Assess technical viability and, if applicable, develop methodology and approach to incorporate wing shape measurements within the vehicle flight control system, and develop and flight validate advanced approaches to perform active wing shape control.
Juszczyk, A S; Clark, R K F; Radford, D R
2009-05-23
The General Dental Council states that 'good dental care is delivered by a team' and restorative treatment is enhanced by communication between team members. Commercial dental laboratories are ideally placed to comment on effective communication. To investigate contemporary attitudes and communication between dentist and dental technician from the technician's perspective. Eight hundred and three dental laboratories were invited to take part in a postal survey covering dentist/laboratory communication and the dentist's understanding of technical procedures. Forty percent of laboratories responded. Only 9% scored communication as very good, 48% scored communication with newly qualified dentists better than with established dentists but only 26% considered that dental students were taught to communicate with dental laboratories effectively. The free comments that the respondents were invited to make identified three distinct themes, 'recognition within the dental team', 'effective communication between dentist and dental technician' and 'dentists lack of technical knowledge'. Effective communication between dentist and dental technician is often poor. It was the view of the dental technicians who responded that newly qualified dentists do not have an appropriate understanding of technical techniques. Dental schools are still not preparing new graduates to communicate effectively with dental laboratories.
ERIC Educational Resources Information Center
Geonetta, Sam C., Ed.
Based on the notion of "reaching out," this proceedings presents papers from the annual meeting of the Council for Programs in Technical and Scientific Communication. Papers in the proceedings are: "Southern Tech's Technical Writing Certificate" (William S. Pfeiffer); "Reach Out and Quack Someone" (Daniel R. Jones);…
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.; Kennedy, John M.
1994-01-01
As part of Phase 4 of the NASA/DOD Aerospace Knowledge Diffusion Research Project, studies were conducted that investigated the technical communications practices of Dutch and U.S. aerospace engineers and scientists. The studies had the following objectives: (1) to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communication to their professions, (2) to determine the use and production of technical communication by aerospace engineers and scientists, (3) to investigate their use of libraries and technical information centers, (4) to investigate their use of and the importance to them of computer and information technology, (5) to examine their use of electronic networks, and (6) to determine their use of foreign and domestically produced technical reports. Self-administered (mail) questionnaires were distributed to Dutch aerospace engineers and scientists at the National Aerospace Laboratory (NLR) in the Netherlands, the NASA Ames Research Center in the U.S., and the NASA Langley Research Center in the U.S. Responses of the Dutch and U.S. participants to selected questions are presented in this paper.
Optical-fiber-based Mueller optical coherence tomography.
Jiao, Shuliang; Yu, Wurong; Stoica, George; Wang, Lihong V
2003-07-15
An optical-fiber-based multichannel polarization-sensitive Mueller optical coherence tomography (OCT) system was built to acquire the Jones or Mueller matrix of a scattering medium, such as biological tissue. For the first time to our knowledge, fiber-based polarization-sensitive OCT was dynamically calibrated to eliminate the polarization distortion caused by the single-mode optical fiber in the sample arm, thereby overcoming a key technical impediment to the application of optical fibers in this technology. The round-trip Jones matrix of the sampling fiber was acquired from the reflecting surface of the sample for each depth scan (A scan) with our OCT system. A new rigorous algorithm was then used to retrieve the calibrated polarization properties of the sample. This algorithm was validated with experimental data. The skin of a rat was imaged with this fiber-based system.
Relativistic quantum cryptography
NASA Astrophysics Data System (ADS)
Molotkov, S. N.; Nazin, S. S.
2003-07-01
The problem of unconditional security of quantum cryptography (i.e. the security which is guaranteed by the fundamental laws of nature rather than by technical limitations) is one of the central points in quantum information theory. We propose a relativistic quantum cryptosystem and prove its unconditional security against any eavesdropping attempts. Relativistitic causality arguments allow to demonstrate the security of the system in a simple way. Since the proposed protocol does not empoly collective measurements and quantum codes, the cryptosystem can be experimentally realized with the present state-of-art in fiber optics technologies. The proposed cryptosystem employs only the individual measurements and classical codes and, in addition, the key distribution problem allows to postpone the choice of the state encoding scheme until after the states are already received instead of choosing it before sending the states into the communication channel (i.e. to employ a sort of "antedate" coding).
Fiber optic oxygen sensor leak detection system for space applications
NASA Astrophysics Data System (ADS)
Kazemi, Alex A.; Goswami, Kish; Mendoza, Edgar A.; Kempen, Lothar U.
2007-09-01
This paper describes the successful test of a multi-point fiber optic oxygen sensor system during the static firing of an Evolved Expandable Launch Vehicle (EELV)/Delta IV common booster core (CBC) rocket engine at NASA's Stennis Flight Center. The system consisted of microsensors (optrodes) using an oxygen gas sensitive indicator incorporated onto an optically transparent porous substrate. The modular optoelectronics and multiplexing network system was designed and assembled utilizing a multi-channel opto-electronic sensor readout unit that monitored the oxygen and temperature response of the individual optrodes in real-time and communicated this information via a serial communication port to a remote laptop computer. The sensor packaging for oxygen consisted of two optrodes - one doped with an indicator sensitive to oxygen, and the other doped with an indicator sensitive to temperature. The multichannel oxygen sensor system is fully reversible. It has demonstrated a dynamic response to oxygen gas in the range of 0% to 100% with 0.1% resolution and a response time of <=10 seconds. The sensor package was attached to a custom fiber optic ribbon cable, which was then connected to a fiber optic trunk communications cable (standard telecommunications-grade fiber) that connected to the optoelectronics module. Each board in the expandable module included light sources, photo-detectors, and associated electronics required for detecting oxygen and temperature. The paper illustrates the sensor design and performance data under field deployment conditions.
1999-11-18
telecommunications and data processing installations, Berlin Offenbach: vde - verlag 4. DIN EN 187000: Specification of optical fiber cables...Berlin Offenbach : vde - verlag 5. DIN EN 188000: Specification of optical fibers, Berlin Offenbach : vde - verlag 6. IEC 60793-1: Optical fibers, Part 1...subsystem of customer premises up to a frequency of 100 MHz. The technical requirements of these balanced cabling systems are defined in the standards EN
NASA Astrophysics Data System (ADS)
Zhang, Fangliu; He, Jing; Deng, Rui; Chen, Qinghui; Chen, Lin
2016-10-01
A modulation format, orthogonal pulse amplitude modulation and discrete multitone modulation (O-PAM-DMT), is experimentally demonstrated in a hybrid fiber-visible laser light communication (fiber-VLLC) system using a cost-effective directly modulated laser and blue laser diode. In addition, low overhead is achieved by utilizing only one training sequence to implement synchronization and channel estimation. Through adjusting the ratio of PAM and DMT signal, three types of O-PAM-DMT signals are investigated. After transmission over a 20-km standard single-mode fiber and 5-m free-space VLLC, the receiver sensitivity for 4.36-Gbit/s O-PAM-DMT signals can be improved by 0.4, 1.4, and 2.7 dB, respectively, at a bit error rate of 1×10-3, compared with a conventional DMT signal.
Communication architecture system for fiber positioning of DESI spectrograph
NASA Astrophysics Data System (ADS)
Kaci, Karim; Glez-de-Rivera, Guillermo; Lopez-Colino, Fernando; Martinez-Garcia, M. Sofia; Masa, Jose L.; Garrido, Javier; Sanchez, Justo; Prada, Francisco
2016-07-01
This paper presents a design proposal for controlling the five thousand fiber positioners within the focal plate of the DESI instrument. Each of these positioners is a robot which allows positioning its optic fiber with a resolution within the range of few microns. The high number and density of these robots poses a challenge for handling the communication from a central control device to each of these five thousand. Furthermore, an additional restriction applies as the required time to communicate to every robot of its position must be smaller than a second. Additionally. a low energy consumption profile is also desired. Both wireless and wired communication protocols have been evaluated, proposing single-technology-based architectures and hybrid ones (a combination of them). Among the wireless solutions, ZigBee and CyFi have been considered. Using simulation tools these wireless protocols have been discarded as they do not allow an efficient communication. The studied wired protocols comprise I2C, CAN and Ethernet. The best solution found is a hybrid multilayer architecture combining both Ethernet and I2C. A 100 Mbps Ethernet based network is used to communicate the central control unit with ten management boards. Each of these boards is a low-cost, low-power embedded device that manages a thirty six degrees sector of the sensing plate. Each of these boards receives the positioning data for five hundred robots and communicate with each one through a fast mode plus I2C bus. This proposal allows to communicate the positioning information for all five thousand robots in 350 ms total.
Erbium-doped fiber amplifier elements for structural analysis sensors
NASA Technical Reports Server (NTRS)
Hanna-Hawver, P.; Kamdar, K. D.; Mehta, S.; Nagarajan, S.; Nasta, M. H.; Claus, R. O.
1992-01-01
The use of erbium-doped fiber amplifiers (EDFA's) in optical fiber sensor systems for structural analysis is described. EDFA's were developed for primary applications as periodic regenerator amplifiers in long-distance fiber-based communication systems. Their in-line amplification performance also makes them attractive for optical fiber sensor systems which require long effective lengths or the synthesis of special length-dependent signal processing functions. Sensor geometries incorporating EDFA's in recirculating and multiple loop sensors are discussed. Noise and polarization birefringence are also considered, and the experimental development of system components is discussed.
Technical Writing: Past, Present and Future
NASA Technical Reports Server (NTRS)
Mathes, J. C. (Compiler); Pinelli, T. E. (Compiler)
1981-01-01
The training of technical writers and the objectives of such education are discussed. Special emphasis was placed on the communication between technical personnel and non-technical personnel. The liabilities that affect technical writers were also discussed.
Conceptualizing the Organizational Role of Technical Communicators: A Systems Approach.
ERIC Educational Resources Information Center
Harrison, Teresa M.; Debs, Mary Beth
1988-01-01
Uses a systems approach to organizational theory to argue that technical communicators function as "boundary spanners," who make sense of and disseminate information required for coordination between organizational groups, and for effective responses to the environment. (JAD)
ERIC Educational Resources Information Center
Zappen, James P., Ed.; Katz, Susan, Ed.
Based on the theme of assessment, this proceedings presents papers and discussions from the annual meeting of the Council for Programs in Technical and Scientific Communication (CPTSC). Three papers in the proceedings discussing curricula are: "Model(s) for Educating Professional Communicators" (Marilyn M. Cooper); "Summary of…
Toward efficient fiber-based quantum interface (Conference Presentation)
NASA Astrophysics Data System (ADS)
Soshenko, Vladimir; Vorobyov, Vadim V.; Bolshedvorsky, Stepan; Lebedev, Nikolay; Akimov, Alexey V.; Sorokin, Vadim; Smolyaninov, Andrey
2016-04-01
NV center in diamond is attracting a lot of attention in quantum information processing community [1]. Been spin system in clean and well-controlled environment of diamond it shows outstanding performance as quantum memory even at room temperature, spin control with single shot optical readout and possibility to build up quantum registers even on single NV center. Moreover, NV centers could be used as high-resolution sensitive elements of detectors of magnetic or electric field, temperature, tension, force or rotation. For all of these applications collection of the light emitted by NV center is crucial point. There were number of approaches suggested to address this issue, proposing use of surface plasmoms [2], manufacturing structures in diamond [3] etc. One of the key feature of any practically important interface is compatibility with the fiber technology. Several groups attacking this problem using various approaches. One of them is placing of nanodiamonds in the holes of photonic crystal fiber [4], another is utilization of AFM to pick and place nanodiamond on the tapered fiber[5]. We have developed a novel technique of placing a nanodiamond with single NV center on the tapered fiber by controlled transfer of a nanodiamond from one "donor" tapered fiber to the "target" clean tapered fiber. We verify our ability to transfer only single color centers by means of measurement of second order correlation function. With this technique, we were able to double collection efficiency of confocal microscope. The majority of the factors limiting the collection of photons via optical fiber are technical and may be removed allowing order of magnitude improved in collection. We also discuss number of extensions of this technique to all fiber excitation and integration with nanostructures. References: [1] Marcus W. Doherty, Neil B. Manson, Paul Delaney, Fedor Jelezko, Jörg Wrachtrup, Lloyd C.L. Hollenberg , " The nitrogen-vacancy colour centre in diamond," Physics Reports, vol. 528, no. 1, p. 1-45, 2013. [2] A.V. Akimov, A. Mukherjee, C.L. Yu, D.E. Chang, A.S. Zibrov, P.R. Hemmer, H. Park and M.D. Lukin, "Generation of single optical plasmons in metallic nanowires coupled to quantum dots," Nature, vol. 450, p. 402-406, 2007. [3] Michael J. Burek , Yiwen Chu, Madelaine S.Z. Liddy, Parth Patel, Jake Rochman , Srujan Meesala, Wooyoung Hong, Qimin Quan, Mikhail D. Lukin and Marko Loncar High quality-factor optical nanocavities in bulk single-crystal diamond, Nature communications 6718 (2014) [4] Tim Schroder, Andreas W. Schell, Gunter Kewes, Thomas Aichele, and Oliver Benson Fiber-Integrated Diamond-Based Single Photon Source, Nano Lett. 2011, 11, 198-202 [5]Lars Liebermeister, et. al. "Tapered fiber coupling of single photons emitted by a deterministically positioned single nitrogen vacancy center", Appl. Phys. Lett. 104, 031101 (2014)
Wavelength division multiplexing of chaotic secure and fiber-optic communications.
Zhang, Jian-Zhong; Wang, An-Bang; Wang, Juan-Fen; Wang, Yun-Cai
2009-04-13
Wavelength division multiplexing (WDM) transmission of chaotic optical communication (COC) and conventional fiber-optic communication (CFOC) is numerically confirmed and analyzed. For an 80-km-long two-channel communication system, a 1-Gb/s secure message in COC channel and 10-Gb/s digital signal in CFOC channel are simultaneously achieved with 100 GHz channel spacing. Our numerical simulations demonstrate that the COC and CFOC can realize no-crosstalk transmission of 80 km when the peak power of CFOC channel is less than 8dBm. We also find that the crosstalk between COC and CFOC does not depend on channel spacing when the channel spacing exceeds 100GHz. Moreover, the crosstalk does not limit channel number by comparing the synchronization performance of COC in four- and six-channel WDM systems.
NASA Astrophysics Data System (ADS)
Ohyama, Takashi; Enomoto, Hiroyuki; Takei, Yuichiro; Maeda, Yuji
2009-05-01
Most of Japan's local governments utilize municipal disaster-management radio communications systems to communicate information on disasters or terrorism to residents. The national government is progressing in efforts toward digitalization by local governments of these systems, but only a small number (approx. 10%) have introduced such equipment due to its requiring large amounts of investment. On the other hand, many local governments are moving forward in installation of optical fiber networks for the purpose of eliminating the "digital divide." We herein propose a communication system as an alternative or supplement to municipal disaster-management radio communications systems, which utilizes municipal optical fiber networks, the internet and similar networks and terminals. The system utilizes the multiple existing networks and is capable of instantly distributing to all residents, and controlling, risk management information. We describe the system overview and the field trials conducted with a local government using this system.
Recent development in blast performance of fiber-reinforced concrete
NASA Astrophysics Data System (ADS)
Hajek, R.; Foglar, M.; Kohoutkova, A.
2017-09-01
The paper presents an overview of the recent development in blast performance of fiber reinforced concrete. The paper builds on more than ten years’ history of the research in this field by the team of the Department of Concrete and Masonry Structures of the Faculty of Civil Engineering of the Czech Technical University in Prague.
Secure communication in fiber optic systems via transmission of broad-band optical noise.
Buskila, O; Eyal, A; Shtaif, M
2008-03-03
We propose a new scheme for data encryption in the physical layer. Our scheme is based on the distribution of a broadband optical noise-like signal between Alice and Bob. The broadband signal is used for the establishment of a secret key that can be used for the secure transmission of information by using the one-time-pad method. We characterize the proposed scheme and study its applicability to the existing fiber-optics communications infrastructure.
Fiber comb filters based on UV-writing Bragg gratings in graded-index multimode fibers
NASA Astrophysics Data System (ADS)
Liu, Yu; Lit, John; Gu, Xijia; Wei, Li
2005-10-01
We report a new kind of comb filters based on fiber Bragg gratings in graded-index multimode fibers. It produces two groups of spectra with a total of 36 reflection peaks that correspond to 18 principal modes and cross coupled modes. The mode indices and wavelength spacings have been investigated theoretically and experimentally. This kind of comb filters may be used to construct multi-wavelength light sources for sensing, optical communications, and instrumentations
Theoretical Studies of Low-Loss Optical Fibers.
1980-09-15
on the fiber surface. Single-mode fiber operation is of interest in communications. Marcuse has shown that surface imperfections are a strong source...0.01 very small value of a : 8A at X = 1 vim Marcuse single mode 2.7 typical value of a = 1 jim, A : 10.6 vm, af = 37 Pim surface imperfections 55...Braunstein, "Scattering Losses in Single and Polycrystalline Materials for Infrared Fiber Applications," unpublished. 5. D. Marcuse , "Mode Conversion
NASA Technical Reports Server (NTRS)
Kennedy, John M.; Pinelli, Thomas E.; Barclay, Rebecca O.
1994-01-01
This paper describes the preliminary analysis of a survey of the American Institute of Aeronautics and Astronautics (AIAA) student members. In the paper we examine (1) the demographic characteristics of the students, (2) factors that affected their career decisions, (3) their career goals and aspirations, and (4) their training in technical communication and techniques for finding and using aerospace scientific and technical information (STI). We determine that aerospace engineering students receive training in technical communication skills and the use of STI. While those in the aerospace industry think that more training is needed, we believe the students receive the appropriate amount of training. We think that the differences between the amount of training students receive and the perception of training needs is related partially to the characteristics of the students and partially to the structure of the aerospace STI dissemination system. Overall, we conclude that the students' technical communication training and knowledge of STI, while limited by external forces, makes it difficult for students to achieve their career goals.
Ultrafast time-stretch imaging at 932 nm through a new highly-dispersive fiber
Wei, Xiaoming; Kong, Cihang; Sy, Samuel; Ko, Ho; Tsia, Kevin K.; Wong, Kenneth K. Y.
2016-01-01
Optical glass fiber has played a key role in the development of modern optical communication and attracted the biotechnology researcher’s great attention because of its properties, such as the wide bandwidth, low attenuation and superior flexibility. For ultrafast optical imaging, particularly, it has been utilized to perform MHz time-stretch imaging with diffraction-limited resolutions, which is also known as serial time-encoded amplified microscopy (STEAM). Unfortunately, time-stretch imaging with dispersive fibers has so far mostly been demonstrated at the optical communication window of 1.5 μm due to lack of efficient dispersive optical fibers operating at the shorter wavelengths, particularly at the bio-favorable window, i.e., <1.0 μm. Through fiber-optic engineering, here we demonstrate a 7.6-MHz dual-color time-stretch optical imaging at bio-favorable wavelengths of 932 nm and 466 nm. The sensitivity at such a high speed is experimentally identified in a slow data-streaming manner. To the best of our knowledge, this is the first time that all-optical time-stretch imaging at ultrahigh speed, high sensitivity and high chirping rate (>1 ns/nm) has been demonstrated at a bio-favorable wavelength window through fiber-optic engineering. PMID:28018737
Ultrafast time-stretch imaging at 932 nm through a new highly-dispersive fiber.
Wei, Xiaoming; Kong, Cihang; Sy, Samuel; Ko, Ho; Tsia, Kevin K; Wong, Kenneth K Y
2016-12-01
Optical glass fiber has played a key role in the development of modern optical communication and attracted the biotechnology researcher's great attention because of its properties, such as the wide bandwidth, low attenuation and superior flexibility. For ultrafast optical imaging, particularly, it has been utilized to perform MHz time-stretch imaging with diffraction-limited resolutions, which is also known as serial time-encoded amplified microscopy (STEAM). Unfortunately, time-stretch imaging with dispersive fibers has so far mostly been demonstrated at the optical communication window of 1.5 μm due to lack of efficient dispersive optical fibers operating at the shorter wavelengths, particularly at the bio-favorable window, i.e., <1.0 μm. Through fiber-optic engineering, here we demonstrate a 7.6-MHz dual-color time-stretch optical imaging at bio-favorable wavelengths of 932 nm and 466 nm. The sensitivity at such a high speed is experimentally identified in a slow data-streaming manner. To the best of our knowledge, this is the first time that all-optical time-stretch imaging at ultrahigh speed, high sensitivity and high chirping rate (>1 ns/nm) has been demonstrated at a bio-favorable wavelength window through fiber-optic engineering.
spent eight years in the United States Air Force where he worked in communication technologies. He also has a certificate in Fiber Optics and Communication Infrastructure Installation. Education M.S
Transmission of Information: An Overview.
ERIC Educational Resources Information Center
Thoma, George R.
1981-01-01
Outlines the basic principles underlying the transmission of information, including analog and digital modulation, limitations to communications, configurations of communications networks, optical fiber cables, and earth satellites. Six references are cited. (FM)
Health benefits of dietary fiber.
Anderson, James W; Baird, Pat; Davis, Richard H; Ferreri, Stefanie; Knudtson, Mary; Koraym, Ashraf; Waters, Valerie; Williams, Christine L
2009-04-01
Dietary fiber intake provides many health benefits. However, average fiber intakes for US children and adults are less than half of the recommended levels. Individuals with high intakes of dietary fiber appear to be at significantly lower risk for developing coronary heart disease, stroke, hypertension, diabetes, obesity, and certain gastrointestinal diseases. Increasing fiber intake lowers blood pressure and serum cholesterol levels. Increased intake of soluble fiber improves glycemia and insulin sensitivity in non-diabetic and diabetic individuals. Fiber supplementation in obese individuals significantly enhances weight loss. Increased fiber intake benefits a number of gastrointestinal disorders including the following: gastroesophageal reflux disease, duodenal ulcer, diverticulitis, constipation, and hemorrhoids. Prebiotic fibers appear to enhance immune function. Dietary fiber intake provides similar benefits for children as for adults. The recommended dietary fiber intakes for children and adults are 14 g/1000 kcal. More effective communication and consumer education is required to enhance fiber consumption from foods or supplements.
47 CFR 27.308 - Technical content of applications.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false Technical content of applications. 27.308 Section 27.308 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.308...
47 CFR 27.308 - Technical content of applications.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 2 2011-10-01 2011-10-01 false Technical content of applications. 27.308 Section 27.308 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Application, Licensing, and Processing Rules for WCS § 27.308...
1993-09-01
Indiana University Bloomington, Indiana doc~ ~ e-an aPP’oveThi %o u E -l:•-,•d sale; its II September 1993 iot public te, an .. itS S =- National...Amount of Time Spent Communicating Technical Information by India and 11 S . Aerospace Engineers and Scientists India U.S. Change % (n) % (n) Increased 83...respondents and 76% of the U.S. respondents indicated that they had taken a course( s ) in technical communications/writing. (Approximately 75% of the India
Crystal-free Formation of Non-Oxide Optical Fiber
NASA Technical Reports Server (NTRS)
Nabors, Sammy A.
2015-01-01
Researchers at NASA Marshall Space Flight Center have devised a method for the creation of crystal-free nonoxide optical fiber preforms. Non-oxide fiber optics are extensively used in infrared transmitting applications such as communication systems, chemical sensors, and laser fiber guides for cutting, welding and medical surgery. However, some of these glasses are very susceptible to crystallization. Even small crystals can lead to light scatter and a high attenuation coefficient, limiting their usefulness. NASA has developed a new method of non-oxide fiber formation that uses axial magnetic fields to suppress crystallization. The resulting non-oxide fibers are crystal free and have lower signal attenuation rates than silica based optical fibers.
29 CFR 1910.901-1910.999 - [Reserved
Code of Federal Regulations, 2010 CFR
2010-07-01
...) Exposure, Permissible .1001(c) Fibers Exposure, Permissible .1001(b) Hazard Communication .1001(j...)(6) Bench and Floor Stands Guarding .215(b)(3) Benzene .1028 Communication of benzene hazards to... .1051(j) Medical Screening and Surveillance .1051(k) Communication of BD Hazards to Employees .1051(l...
29 CFR 1910.901-1910.999 - [Reserved
Code of Federal Regulations, 2012 CFR
2012-07-01
...) Exposure, Permissible .1001(c) Fibers Exposure, Permissible .1001(b) Hazard Communication .1001(j...)(6) Bench and Floor Stands Guarding .215(b)(3) Benzene .1028 Communication of benzene hazards to... .1051(j) Medical Screening and Surveillance .1051(k) Communication of BD Hazards to Employees .1051(l...
Faraday-Michelson system for quantum cryptography.
Mo, Xiao-Fan; Zhu, Bing; Han, Zheng-Fu; Gui, You-Zhen; Guo, Guang-Can
2005-10-01
Quantum key distribution provides unconditional security for communication. Unfortunately, current experimental schemes are not suitable for long-distance fiber transmission because of phase drift or Rayleigh backscattering. In this Letter we present a unidirectional intrinsically stable scheme that is based on Michelson-Faraday interferometers, in which ordinary mirrors are replaced with 90 degree Faraday mirrors. With the scheme, a demonstration setup was built and excellent stability of interference fringe visibility was achieved over a fiber length of 175 km. Through a 125 km long commercial communication fiber cable between Beijing and Tianjin, the key exchange was performed with a quantum bit-error rate of less than 6%, which is to our knowledge the longest reported quantum key distribution experiment under field conditions.
ERIC Educational Resources Information Center
Roberts, Carleton W.
1973-01-01
Discusses the present status of technician and technology-oriented institutions and the two curricula offered by the Textile Department, Clemson University. Indicates that technical school, junior college, and community college graduates are allowed to complete formal training to the four-year degree level in the Clemson program. (CC)
[Operation/Maintenance of Fiber Placement Machine
NASA Technical Reports Server (NTRS)
Pelham, L.; Dillard, T.
2000-01-01
NASA contract NAS8-39749 was completed in January 2000. The contract period of performance covered six (6) years and included basic program technical support as required by NASA with up to thirty (30) different technical directives identified and issued by NASA for specific Advanced Composite Technology tasks during the course of the contract.
Wright, Malcolm W; Morris, Jeffery F; Kovalik, Joseph M; Andrews, Kenneth S; Abrahamson, Matthew J; Biswas, Abhijit
2015-12-28
An adaptive optics (AO) testbed was integrated to the Optical PAyload for Lasercomm Science (OPALS) ground station telescope at the Optical Communications Telescope Laboratory (OCTL) as part of the free space laser communications experiment with the flight system on board the International Space Station (ISS). Atmospheric turbulence induced aberrations on the optical downlink were adaptively corrected during an overflight of the ISS so that the transmitted laser signal could be efficiently coupled into a single mode fiber continuously. A stable output Strehl ratio of around 0.6 was demonstrated along with the recovery of a 50 Mbps encoded high definition (HD) video transmission from the ISS at the output of the single mode fiber. This proof of concept demonstration validates multi-Gbps optical downlinks from fast slewing low-Earth orbiting (LEO) spacecraft to ground assets in a manner that potentially allows seamless space to ground connectivity for future high data-rates network.
NASA Astrophysics Data System (ADS)
Walker, Ernest L.
1994-05-01
This paper presents results of a theoretical investigation to evaluate the performance of code division multiple access communications over multimode optical fiber channels in an asynchronous, multiuser communication network environment. The system is evaluated using Gold sequences for spectral spreading of the baseband signal from each user employing direct-sequence biphase shift keying and intensity modulation techniques. The transmission channel model employed is a lossless linear system approximation of the field transfer function for the alpha -profile multimode optical fiber. Due to channel model complexity, a correlation receiver model employing a suboptimal receive filter was used in calculating the peak output signal at the ith receiver. In Part 1, the performance measures for the system, i.e., signal-to-noise ratio and bit error probability for the ith receiver, are derived as functions of channel characteristics, spectral spreading, number of active users, and the bit energy to noise (white) spectral density ratio. In Part 2, the overall system performance is evaluated.
Conceptual designs of onboard transceivers for ground-to-satellite quantum cryptography
NASA Astrophysics Data System (ADS)
Toyoshima, Morio; Shoji, Yozo; Takayama, Yoshihisa; Kunimori, Hiroo; Takeoka, Masahiro; Fujiwara, Mikio; Sasaki, Masahide
2009-05-01
A free-space quantum key distribution system is being developed by the National Institute of Information and Communications Technology (NICT) in Koganei, Japan. Quantum cryptography is a new technique for transmitting information where the security is guaranteed by the laws of physics. In such systems, a single photon is used for the quantum information. However, since the transmission distance in optical fibers is limited by the absorption of photons by the fiber, the maximum demonstrated range has been limited to about 100 km. Free-space quantum cryptography between an optical ground station and a satellite is a possible solution to extend the distance for a quantum network beyond the limits of optical fibers. At NICT, a laser communication demonstration between the NICT optical ground station and a low earth orbit satellite was successfully conducted in 2006. The use of free-space quantum key distribution for such space communication links is considered an important future application. This paper presents conceptual designs for the onboard transceivers for satellite quantum cryptography
ERIC Educational Resources Information Center
Duda, Richard
The immediate objective of this course in technical English was to enable French-speaking mechanics and technicians to read the instructions for the installation, operation and upkeep of American-made machinery. Although the learners knew very little English, available British and American technical documents were used because of their…
ERIC Educational Resources Information Center
Rude, Carolyn, Ed.
Based on the theme of the past, present, and future of science, technology, and communication programs, this proceedings presents 49 papers delivered at the 1999 annual meeting of the Council for Programs in Technical and Scientific Communication (CPTSC). Papers in the proceedings are divided into 12 subsections: The Shape of Programs: Past,…
NASA Astrophysics Data System (ADS)
Lukiyanchuk, I. V.; Rudnev, V. S.; Serov, M. M.; Krit, B. L.; Lukiyanchuk, G. D.; Nedozorov, P. M.
2018-04-01
The catalytic activity of both copper fibers and copper-coated fibers of a diameter of 50-100 μm made of aluminum alloy, technical grade titanium, and FeCrAl alloy in CO oxidation has been estimated. Metal fibers have been fabricated by the method of pendant drop melt extraction (PDME). The fibers copper plating was carried out by chemical and electrochemical methods. The composition and structure of samples and coatings before and after catalytic tests have been characterized by the methods of scanning electron microscopy, energy-dispersive analysis, and X-ray fluorescence analysis. It has been shown that the catalytic activity of copper-coated fibers made of FeCrAl alloy in the reaction of CO oxidation is not inferior to that of copper fibers.
NASA Astrophysics Data System (ADS)
Minke, Christine; Kunz, Ulrich; Turek, Thomas
2017-02-01
Carbon felt electrodes belong to the key components of redox flow batteries. The purpose of this techno-economic assessment is to uncover the production costs of PAN- and rayon-based carbon felt electrodes. Raw material costs, energy demand and the impact of processability of fiber and felt are considered. This innovative, interdisciplinary approach combines deep insights into technical, ecologic and economic aspects of carbon felt and carbon fiber production. Main results of the calculation model are mass balances, cumulative energy demands (CED) and the production costs of conventional and biogenic carbon felts supplemented by market assessments considering textile and carbon fibers.
Fiber Optic Wing Shape Sensing on NASA's Ikhana UAV
NASA Technical Reports Server (NTRS)
Richards, Lance; Parker, Allen R.; Ko, William L.; Piazza, Anthony
2008-01-01
This document discusses the development of fiber optic wing shape sensing on NASA's Ikhana vehicle. The Dryden Flight Research Center's Aerostructures Branch initiated fiber-optic instrumentation development efforts in the mid-1990s. Motivated by a failure to control wing dihedral resulting in a mishap with the Helios aircraft, new wing displacement techniques were developed. Research objectives for Ikhana included validating fiber optic sensor measurements and real-time wing shape sensing predictions; the validation of fiber optic mathematical models and design tools; assessing technical viability and, if applicable, developing methodology and approaches to incorporate wing shape measurements within the vehicle flight control system; and, developing and flight validating approaches to perform active wing shape control using conventional control surfaces and active material concepts.
Some Protocols For Optical-Fiber Digital Communications
NASA Technical Reports Server (NTRS)
Yeh, Cavour; Gerla, Mario
1989-01-01
One works best in heavy traffic, another, in light traffic. Three protocols proposed for digital communications among stations connected by passive taps to pair of uni-directional optical-fiber buses. Mediate round-robin, bounded-delay access to buses by all stations and particularly suited to fast transmission. Partly because transmission medium passive (no relay stations) and partly because protocols distribute control of network among all stations with provision for addition and deletion of stations (no control stations), communication network able to resist and recover from failures. Implicit token propagates in one direction on one bus and in opposite direction on other bus, minimizing interval of silence between end of one round and beginning of next.
Brown, Andrea M; Hahn, Daniel V; Brown, David M; Rolander, Nathan W; Bair, Chun-Huei; Sluz, Joseph E
2012-06-20
A gimbal-free wide field-of-regard (FOR) optical receiver has been built in a laboratory setting for proof-of-concept testing. Multiple datasets are presented that examine the overall FOR of the system and the receiver's ability to track and collect a signal from a moving source. The design is not intended to compete with traditional free space optical communication systems, but rather offer an alternative design that minimizes the number and complexity of mechanical components required at the surface of a small mobile platform. The receiver is composed of a micro-lens array and hexagonal bundles of large core optical fibers that route the optical signal to remote detectors and electronics. Each fiber in the bundle collects power from a distinct solid angle of space and a piezo-electric transducer is used to translate the micro-lens array and optimize coupling into a given fiber core in the bundle. The micro-lens to fiber bundle design is scalable, modular, and can be replicated in an array to increase aperture size.
Engineering ultra-flattened normal dispersion photonic crystal fiber with silica material
NASA Astrophysics Data System (ADS)
Ferhat, Mohamed Lamine; Cherbi, Lynda; Bahloul, Lies; Hariz, Abdelhafid
2017-05-01
The tailoring of the group velocity dispersion (GVD) of an optical fiber is critical in many applications, influence on the bandwidth of information transmission in optical communication systems, successful utilization of nonlinear optical properties in applications such as supercontinuum generation, wavelength conversion and harmonic generation via stimulated Raman scattering ...In this work, we propose a design of ultra-flattened photonic crystal fiber by changing the diameter of the air holes of the cladding rings. The geometry is composed of only four rings, hexagonal structure of air holes and silica as background of the solid core. As a result, we present structures with broadband flat normal dispersion on many wavelengths bands useful for several applications. We obtain flat normal dispersion over 1000 nm broadband flat normal dispersion below -7 [ps/nm.km], and ultra-flat near zero normal dispersion below -0.2 [ps/nm.km] over 150 nm. The modeled photonic crystal fiber would be valuable for the fabrication of ultra-flattened-dispersion fibers, and have potential applications in wide-band high-speed optical communication systems, supercontinuum generation and many other applications.
Design of an Fiber-Coupled Laser Heterodyne Interferometer for the FLARE
NASA Astrophysics Data System (ADS)
Frank, Samuel; Yoo, Jongsoo; Ji, Hantao; Jara-Almonte, Jon
2016-10-01
The FLARE (Facility for Laboratory Reconnection Experiments), which is currently under construction at PPPL, requires a complete set of laboratory plasma diagnostics. The Langmuir probes that will be used in the device to gather local density data require a reliable interferometer system to serve as baseline for density measurement calibration. A fully fiber-coupled infrared laser heterodyne interferometer has been designed in order to serve as the primary line-integrated electron density diagnostic. Thanks to advances in the communications industry many fiber optic devices and phase detection methods have advanced significantly becoming increasingly reliable and inexpensive. Fully fiber coupling a plasma interferometer greatly simplifies alignment procedures needed since the only free space laser path needing alignment is through the plasma itself. Fiber-coupling also provides significant resistance to vibrational noise, a common problem in plasma interferometry systems. This device also uses a greatly simplified phase detection scheme in which chips, originally developed for the communications industry, capable of directly detecting the phase shift of a signal with high time resolution. The design and initial performance of the system will be discussed.
Implications of Metaphors in Defining Technical Communication.
ERIC Educational Resources Information Center
Beck, Charles E.
1991-01-01
Identifies four metaphors that appear dominant in current studies in the field of technical communication: transmitter, channel, balance, and bridge. Suggests limitations upon each of the metaphors. Discusses the alternative metaphors of lock, translator, transformer, synthesizer, conductor, and orchestrator. Proposes orchestration as a fruitful…
Development of a comprehensive inventory management system for underground fiber optic conduits.
DOT National Transportation Integrated Search
2013-03-01
Major State Departments of Transportation operate and maintain networks of thousands of miles of conduits, many : carrying fiber optic cables that are vital to State communication systems. These conduits are located alongside or : across highways and...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-30
... Communications Network Corp., and Vicon Fiber Optics Corp.; Order of Suspension of Trading June 28, 2010. It... Vicon Fiber Optics Corp. because it has not filed any periodic reports since the period ended September...
Personal cooling apparatus and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siman-Tov, Moshe; Crabtree, Jerry Allen
2001-01-01
A portable lightweight cooling apparatus for cooling a human body is disclosed, having a channeled sheet which absorbs sweat and/or evaporative liquid, a layer of highly conductive fibers adjacent the channeled sheet; and, an air-moving device for moving air through the channeled sheet, wherein the layer of fibers redistributes heat uniformly across the object being cooled, while the air moving within the channeled sheet evaporates sweat and/or other evaporative liquid, absorbs evaporated moisture and the uniformly distributed heat generated by the human body, and discharges them into the environment. Also disclosed is a method for removing heat generated by themore » human body, comprising the steps of providing a garment to be placed in thermal communication with the body; placing a layer of highly conductive fibers within the garment adjacent the body for uniformly distributing the heat generated by the body; attaching an air-moving device in communication with the garment for forcing air into the garment; removably positioning an exchangeable heat sink in communication with the air-moving device for cooling the air prior to the air entering the garment; and, equipping the garment with a channeled sheet in communication with the air-moving device so that air can be directed into the channeled sheet and adjacent the layer of fibers to expell heat and moisture from the body by the air being directed out of the channeled sheet and into the environment. The cooling system may be configured to operate in both sealed and unsealed garments.« less
Personal cooling apparatus and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siman-Tov, Moshe; Crabtree, Jerry Allen
A portable lightweight cooling apparatus for cooling a human body is disclosed, having a channeled sheet which absorbs sweat and/or evaporative liquid, a layer of highly conductive fibers adjacent the channeled sheet; and, an air-moving device for moving air through the channeled sheet, wherein the layer of fibers redistributes heat uniformly across the object being cooled, while the air moving within the channeled sheet evaporates sweat and/or other evaporative liquid, absorbs evaporated moisture and the uniformly distributed heat generated by the human body, and discharges them into the environment. Also disclosed is a method for removing heat generated by themore » human body, comprising the steps of providing a garment to be placed in thermal communication with the body; placing a layer of highly conductive fibers within the garment adjacent the body for uniformly distributing the heat generated by the body; attaching an air-moving device in communication with the garment for forcing air into the garment; removably positioning an exchangeable heat sink in communication with the air-moving device for cooling the air prior to the air entering the garment; and, equipping the garment with a channeled sheet in communication with the air-moving device so that air can be directed into the channeled sheet and adjacent the layer of fibers to expell heat and moisture from the body by the air being directed out of the channeled sheet and into the environment. The cooling system may be configured to operate in both sealed and unsealed garments.« less
Personal cooling apparatus and method
Siman-Tov, Moshe; Crabtree, Jerry Allen
2001-01-01
A portable lightweight cooling apparatus for cooling a human body is disclosed, having a channeled sheet which absorbs sweat and/or evaporative liquid, a layer of highly conductive fibers adjacent the channeled sheet; and, an air-moving device for moving air through the channeled sheet, wherein the layer of fibers redistributes heat uniformly across the object being cooled, while the air moving within the channeled sheet evaporates sweat and/or other evaporative liquid, absorbs evaporated moisture and the uniformly distributed heat generated by the human body, and discharges them into the environment. Also disclosed is a method for removing heat generated by the human body, comprising the steps of providing a garment to be placed in thermal communication with the body; placing a layer of highly conductive fibers within the garment adjacent the body for uniformly distributing the heat generated by the body; attaching an air-moving device in communication with the garment for forcing air into the garment; removably positioning an exchangeable heat sink in communication with the air-moving device for cooling the air prior to the air entering the garment; and, equipping the garment with a channeled sheet in communication with the air-moving device so that air can be directed into the channeled sheet and adjacent the layer of fibers to expell heat and moisture from the body by the air being directed out of the channeled sheet and into the environment. The cooling system may be configured to operate in both sealed and unsealed garments.
Partial Ordering and Stochastic Resonance in Discrete Memoryless Channels
2012-05-01
Methods for Underwater Wireless Sensor Networks”, which is to analyze and develop noncoherent communication methods at the physical layer for target...Capacity Behavior for Simple Models of Optical Fiber Communication,” 8 th International conf. on Communications, COMM 2010, Bucharest, pp.1-6, July 2010
Next generation information communication infrastructure and case studies for future power systems
NASA Astrophysics Data System (ADS)
Qiu, Bin
As power industry enters the new century, powerful driving forces, uncertainties and new functions are compelling electric utilities to make dramatic changes in their information communication infrastructure. Expanding network services such as real time measurement and monitoring are also driving the need for more bandwidth in the communication network. These needs will grow further as new remote real-time protection and control applications become more feasible and pervasive. This dissertation addresses two main issues for the future power system information infrastructure: communication network infrastructure and associated power system applications. Optical networks no doubt will become the predominant data transmission media for next generation power system communication. The rapid development of fiber optic network technology poses new challenges in the areas of topology design, network management and real time applications. Based on advanced fiber optic technologies, an all-fiber network is investigated and proposed. The study will cover the system architecture and data exchange protocol aspects. High bandwidth, robust optical networks could provide great opportunities to the power system for better service and efficient operation. In the dissertation, different applications are investigated. One of the typical applications is the SCADA information accessing system. An Internet-based application for the substation automation system will be presented. VLSI (Very Large Scale Integration) technology is also used for one-line diagrams auto-generation. High transition rate and low latency optical network is especially suitable for power system real time control. In the dissertation, a new local area network based Load Shedding Controller (LSC) for isolated power system will be presented. By using PMU (Phasor Measurement Unit) and fiber optic network, an AGE (Area Generation Error) based accurate wide area load shedding scheme will also be proposed. The objective is to shed the load in the limited area with minimum disturbance.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Holloway, Karen; Sato, Yuko; Barclay, Rebecca O.; Kennedy, John M.
1996-01-01
To understand the diffusion of aerospace knowledge, it is necessary to understand the communications practices and the information-seeking behaviors of those involved in the production, transfer, and use of aerospace knowledge at the individual, organizational, national, and international levels. In this paper, we report selected results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on communications practices and information-seeking behaviors in the workplace. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communications, use of libraries, the use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports. The responses of the survey respondents are placed within the context of the Japanese culture. We assume that differences in Japanese and U.S. cultures influence the communications practices and information-seeking behaviors of Japanese and U.S. aerospace engineers and scientists.
Navy Budget (1992): Potential Reductions in Research, Development, Test, and Evaluation Programs
1991-09-01
Army’s fiber optic guided missile employs a video camera and single spool fiber payout system to provide a contin- uous data link to a ground station for...January 1991 the Navy’s technical design agent for the MK-48 tor- pedo has been directing a major research and testing effort. The results of these
The Need for US Coast Guard Underwater Mission Development
2013-04-23
vehicles and proliferation of fiber optic cables, raising the level of human interactions in the underwater environment. Besides the benefits from the...unmanned underwater vehicles, proliferation of fiber optic cables, and observation posts on the ocean floor will raise the level of human interactions...world’s demand for wood grows.39 As technology progresses, undersea infrastructure will continue to expand. Already, underwater fiber optic communication
2006-05-03
AFRL-DE-PS- AFRL-DE-PS- TR-2006-1059 TR-2006-1059 FIBER LASER ARRAYS Thomas B. Simpson L-3 Communications-Jaycor 3394...LEANNE J HENRY, Lt Col, USAF L. BRUCE SIMPSON, SES Chief, High Power Solid State Laser Branch Director, Directed Energy Directorate...SUBTITLE Fiber Laser Arrays 5c. PROGRAM ELEMENT NUMBER 62605F 5d. PROJECT NUMBER 4866 5e. TASK NUMBER LR 6. AUTHOR(S) Thomas B. Simpson
Development Of Fiber Optics For Passenger Car Applications
NASA Astrophysics Data System (ADS)
Steele, R. E.; Schmitt, H. J.
1987-12-01
The benefits of fiber optics for telecommunications and Local Area Networks (LANs) are well documented. The benefits to passenger car applications are not as clearly defined. This paper examines the differences between Telecommunications, LAN, and automotive point to point and network applications. Current production automotive applications of optics and fiber optics, automotive data communications trends, and both functional and non-functional requirements and constraints will be described.
NASA Astrophysics Data System (ADS)
Filippi, G.; Ibsen, J.; Jaque, S.; Liello, F.; Ovando, N.; Astudillo, A.; Parra, J.; Saldias, Christian
2016-07-01
Announced in 2012, started in 2013 and completed in 2015, the ALMA high bandwidth communication system has become a key factor to achieve the operational and scientific goals of ALMA. This paper summarizes the technical, organizational, and operational goals of the ALMA Optical Link Project, focused in the creation and operation of an effective and sustainable communication infrastructure to connect the ALMA Operations Support Facility and Array Operations Site, both located in the Atacama Desert in the Northern region of Chile, with the point of presence of REUNA in Antofagasta, about 400km away, and from there to the Santiago Central Office in the Chilean capital through the optical infrastructure created by the EC-funded EVALSO project and now an integral part of the REUNA backbone. This new infrastructure completed in 2014 and now operated on behalf of ALMA by REUNA, the Chilean National Research and Education Network, uses state of the art technologies, like dark fiber from newly built cables and DWDM transmission, allowing extending the reach of high capacity communication to the remote region where the Observatory is located. The paper also reports on the results obtained during the first year and a half testing and operation period, where different operational set ups have been experienced for data transfer, remote collaboration, etc. Finally, the authors will present a forward look of the impact of it to both the future scientific development of the Chajnantor Plateau, where many installations area are (and will be) located, as well as the potential Chilean scientific backbone long term development.
Marketing information: The technical report as product
NASA Technical Reports Server (NTRS)
Stoher, F. F.; Pinelli, T. E.
1981-01-01
Technical reports constitute a product, the primary means for communicating the results of research to the user. The Langley scientific and technical information (STI) review and evaluation project undertook a review of the technical report as an effective product for information communication. Style manuals describing theory and practice in technical report preparation; publication manuals covering such factors as design, layout, and type style; and copies of technical reports were obtained from industrial, academic, governmental, and research organizations. Based on an analysis of this material, criteria will be established for the report components, for the relationship of the components within the report context, and for the overall report organization. The criteria will be used as bench marks and compared with the publication standards currently used to prepare NASA technical reports.
An Online Approach to Teaching International Outsourcing in Technical Communication Classes
ERIC Educational Resources Information Center
St. Amant, Kirk
2005-01-01
The growth of international online access has given rise to a new production method--international outsourcing--that has important implications for technical communication practices. Successful interactions within international outsourcing require individuals to understand how cultural factors could affect online interactions. Today's technical…
The Technical Communicator and ISO 9000.
ERIC Educational Resources Information Center
Weiss, Edmond H.
1993-01-01
Describes the complexities of ISO 9000, a set of generic quality standards to which any commercial firm wishing to do business with a member firm of the European Economic Community will have to comply. Describes opportunities for professional technical communicators in providing the required product documentation. (SR)
NASA Astrophysics Data System (ADS)
Hutsel, Michael R.
2011-07-01
Optical fiber technology continues to advance rapidly as a result of the increasing demands on communication systems and the expanding use of fiber-based sensing. New optical fiber types and fiber-based communications components are required to permit higher data rates, an increased number of channels, and more flexible installation requirements. Fiber-based sensors are continually being developed for a broad range of sensing applications, including environmental, medical, structural, industrial, and military. As optical fibers and fiber-based devices continue to advance, the need to understand their fundamental physical properties increases. The residual-stress distribution (RSD) and the refractive-index distribution (RID) play fundamental roles in the operation and performance of optical fibers. Custom RIDs are used to tailor the transmission properties of fibers used for long-distance transmission and to enable fiber-based devices such as long-period fiber gratings (LPFGs). The introduction and modification of RSDs enable specialty fibers, such as polarization-maintaining fiber, and contribute to the operation of fiber-based devices. Furthermore, the RSD and the RID are inherently linked through the photoelastic effect. Therefore, both the RSD and the RID need to be characterized because these fundamental properties are coupled and affect the fabrication, operation, and performance of fibers and fiber-based devices. To characterize effectively the physical properties of optical fibers, the RSD and the RID must be measured without perturbing or destroying the optical fiber. Furthermore, the techniques used must not be limited in detecting small variations and asymmetries in all directions through the fiber. Finally, the RSD and the RID must be characterized concurrently without moving the fiber to enable the analysis of the relationship between the RSD and the RID. Although many techniques exist for characterizing the residual stress and the refractive index in optical fibers, there is no existing methodology that meets all of these requirements. Therefore, the primary objective of the research presented in this thesis was to provide a methodology that is capable of characterizing concurrently the three-dimensional RSD and RID in optical fibers and fiber-based devices. This research represents a detailed study of the requirements for characterizing optical fibers and how these requirements are met through appropriate data analysis and experimental apparatus design and implementation. To validate the developed methodology, the secondary objective of this research was to characterize both unperturbed and modified optical fibers. The RSD and the RID were measured in a standard telecommunications-grade optical fiber, Corning SMF-28. The effects of cleaving this fiber were also analyzed and the longitudinal variations that result from cleaving were explored for the first time. The fabrication of carbon-dioxide-laser-induced (CO2 -laser-induced) LPFGs was also examined. These devices provide many of the functionalities required for fiber-based communications components as well as fiber-based sensors, and they offer relaxed fabrication requirements when compared to LPFGs fabricated by other methods. The developed methodology was used to perform the first measurements of the changes that occur in the RSD and the RID during LPFG fabrication. The analysis of these measurements ties together many of the existing theories of CO2-laser-induced LPFG fabrication to present a more coherent understanding of the processes that occur. In addition, new evidence provides detailed information on the functional form of the RSD and the RID in LPFGs. This information is crucial for the modeling of LPFG behavior, for the design of LPFGs for specific applications, for the tailoring of fabrication parameters to meet design requirements, and for understanding the limitations of LPFG fabrication in commercial optical fibers. Future areas of research concerning the improvement of the developed methodology, the need to characterize other fibers and fiber-based devices, and the characterization of CO2-laser-induced LPFGs are identified and discussed.
Utilisation of corn (Zea mays) bran and corn fiber in the production of food components.
Rose, Devin J; Inglett, George E; Liu, Sean X
2010-04-30
The milling of corn for the production of food constituents results in a number of low-value co-products. Two of the major co-products produced by this operation are corn bran and corn fiber, which currently have low commercial value. This review focuses on current and prospective research surrounding the utilization of corn fiber and corn bran in the production of potentially higher-value food components. Corn bran and corn fiber contain potentially useful components that may be harvested through physical, chemical or enzymatic means for the production of food ingredients or additives, including corn fiber oil, corn fiber gum, cellulosic fiber gels, xylo-oligosaccharides and ferulic acid. Components of corn bran and corn fiber may also be converted to food chemicals such as vanillin and xylitol. Commercialization of processes for the isolation or production of food products from corn bran or corn fiber has been met with numerous technical challenges, therefore further research that improves the production of these components from corn bran or corn fiber is needed.
Surveys of facilities for the potential effects from the fallout of airborne graphite fibers
NASA Technical Reports Server (NTRS)
Butterfield, A. J.
1980-01-01
The impact of the entry of graphite fibers into workplaces in the United States is discussed. Areas where an electrical failure could cause major problems include process and production systems, hospitals, and police/fire emergency communication systems.
More than Fiber: Distance Education in Iowa.
ERIC Educational Resources Information Center
Simonson, Michael; Schlosser, Charles
1995-01-01
Describes distance education programs in Iowa, including the Iowa Distance Education Alliance developed through the Department of Education's Star Schools Program; the use of fiber optic technology; and the Iowa Communications Network that links colleges, universities, and secondary schools with public television. (LRW)
Apparatus for Teaching Physics: Optical Fiber Communications.
ERIC Educational Resources Information Center
Throckmorton, Carl; Dey, Joe
1988-01-01
Describes a demonstration of the transmission of data signals from one microcomputer to another using an optical fiber line. Discusses the set-up method and demonstration steps for sending program and graphics. Provides a block diagram of the system and two circuit diagrams. (YP)
Study of Man-Machine Communications Systems for the Handicapped. Interim Report.
ERIC Educational Resources Information Center
Kafafian, Haig
Newly developed communications systems for exceptional children include Cybercom; CYBERTYPE; Cyberplace, a keyless keyboard; Cyberphone, a telephonic communication system for deaf and speech impaired persons; Cyberlamp, a visual display; Cyberview, a fiber optic bundle remote visual display; Cybersem, an interface for the blind, fingerless, and…
ERIC Educational Resources Information Center
Barnett, Cynthia; Miller, Greg; Polito, Thomas A.; Gibson, Lance
2009-01-01
The purpose of this quasi-experimental study was to determine if upper-level college students who participated in AgPAQ, an integrated course cluster learning community, would demonstrate enhanced learning in the areas of oral communication, written communication, and agronomic/economic technical content knowledge. The population (N = 182)…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Kevin P.
2015-02-13
This final technical report details research works performed supported by a Department of Energy grant (DE-FE0003859), which was awarded under the University Coal Research Program administrated by National Energy Technology Laboratory. This research program studied high temperature fiber sensor for harsh environment applications. It developed two fiber optical sensor platform technology including regenerative fiber Bragg grating sensors and distributed fiber optical sensing based on Rayleigh backscattering optical frequency domain reflectometry. Through the studies of chemical and thermal regenerative techniques for fiber Bragg grating (FBG) fabrication, high-temperature stable FBG sensors were successfully developed and fabricated in air-hole microstructured fibers, high-attenuation fibers,more » rare-earth doped fibers, and standard telecommunication fibers. By optimizing the laser processing and thermal annealing procedures, fiber grating sensors with stable performance up to 1100°C have been developed. Using these temperature-stable FBG gratings as sensor platform, fiber optical flow, temperature, pressure, and chemical sensors have been developed to operate at high temperatures up to 800°C. Through the integration of on-fiber functional coating, the use of application-specific air-hole microstructural fiber, and application of active fiber sensing scheme, distributed fiber sensor for temperature, pressure, flow, liquid level, and chemical sensing have been demonstrated with high spatial resolution (1-cm or better) with wide temperature ranges. These include the demonstration of 1) liquid level sensing from 77K to the room temperature, pressure/temperature sensing from the room temperature to 800C and from the 15psi to 2000 psi, and hydrogen concentration measurement from 0.2% to 10% with temperature ranges from the room temperature to 700°C. Optical sensors developed by this program has broken several technical records including flow sensors with the highest operation temperature up to 750°C, first distributed chemical measurements at the record high temperature up to 700°C, first distributed pressure measurement at the record high temperature up to 800°C, and the fiber laser sensors with the record high operation temperature up to 700°C. The research performed by this program dramatically expand the functionality, adaptability, and applicability of distributed fiber optical sensors with potential applications in a number of high-temperature energy systems such as fossil-fuel power generation, high-temperature fuel cell applications, and potential for nuclear energy systems.« less
1998-05-26
therefore, produce higher propagation losses. A. Theory The presence of losses in the cladding modes renders their propagation constants complex...growth theory [10, 11] by tf(L,F,Ga)= ’ n + \\ „4-1 (" + l) 0 F \\ L <C (1) where L is the service length, L0 is the fiber gauge length, and m is...single input pulse, (p. 114) 8:30am BMB2 ■ Ultrashort purse propagation through fiber gratings: theory and experiment, L.R. Chen, S.D. Benjamin
Technical communication. Perspectives for the Eighties, part 2
NASA Technical Reports Server (NTRS)
Mathes, J. C. (Compiler); Pinelli, T. E. (Compiler)
1981-01-01
The importance of technical writing as a separate discipline is suggested. Some specific areas addressed were: technical writing skills industry needs, definitions of technical writing, the hows and whys of inhouse writing, and the nature of the composing process in technical comunication.
Fiberoptic characteristics for extreme operating environments
NASA Technical Reports Server (NTRS)
Delcher, R. C.
1992-01-01
Fiberoptics could offer several major benefits for cryogenic liquid-fueled rocket engines, including lightning immunity, weight reduction, and the possibility of implementing a number of new measurements for engine condition monitoring. The technical feasibility of using fiberoptics in the severe environments posed by cryogenic liquid-fueled rocket engines was determined. The issues of importance and subsequent requirements for this use of fiberoptics were compiled. These included temperature ranges, moisture embrittlement succeptability, and the ability to withstand extreme shock and vibration levels. Different types of optical fibers were evaluated and several types of optical fibers' ability to withstand use in cryogenic liquid-fueled rocket engines was demonstrated through environmental testing of samples. This testing included: cold-bend testing, moisture embrittlement testing, temperature cycling, temperature extremes testing, vibration testing, and shock testing. Three of five fiber samples withstood the tests to a level proving feasibility, and two of these remained intact in all six of the tests. A fiberoptic bundle was also tested, and completed testing without breakage. Preliminary cabling and harnessing for fiber protection was also demonstrated. According to cable manufacturers, the successful -300 F cold bend, vibration, and shock tests are the first instance of any major fiberoptic cable testing below roughly -55 F. This program has demonstrated the basic technical feasibility of implementing optical fibers on cryogenic liquid-fueled rocket engines, and a development plan is included highlighting requirements and issues for such an implementation.
NASA Astrophysics Data System (ADS)
Murshid, Syed H.; Finch, Michael F.; Lovell, Gregory L.
2014-09-01
Spatial domain multiplexing (SDM) is a system that allows multiple channels of light to traverse a single fiber, utilizing separate spatial regions inside the carrier fiber, thereby applying a new degree of photon freedom for optical fiber communications. These channels follow a helical pattern, the screen projection of which is viewable as concentric rings at the output end of the system. The MIMO nature of the SDM system implies that a typical pin-diode or APD will be unable to distinguish between these channels, as the diode will interpret the combination of the SDM signals from all channels as a single signal. As such, spatial de-multiplexing methods must be introduced to properly detect the SDM based MIMO signals. One such method utilizes a fiber consisting of multiple, concentric, hollow core fibers to route each channel independently and thereby de-mux the signals into separate fibers or detectors. These de-mux fibers consist of hollow core cylindrical structures with beveled edges on one side that gradually taper to route the circular, ring type, output energy patterns into a spot with the highest possible efficiency. This paper analyzes the beveled edge by varying its length and analyzing the total output power for each predetermined length allowing us to simulate ideal bevel length to minimize both system losses as well as total de-mux footprint. OptiBPM simulation engine is employed for these analyses.
A formal protocol test procedure for the Survivable Adaptable Fiber Optic Embedded Network (SAFENET)
NASA Astrophysics Data System (ADS)
High, Wayne
1993-03-01
This thesis focuses upon a new method for verifying the correct operation of a complex, high speed fiber optic communication network. These networks are of growing importance to the military because of their increased connectivity, survivability, and reconfigurability. With the introduction and increased dependence on sophisticated software and protocols, it is essential that their operation be correct. Because of the speed and complexity of fiber optic networks being designed today, they are becoming increasingly difficult to test. Previously, testing was accomplished by application of conformance test methods which had little connection with an implementation's specification. The major goal of conformance testing is to ensure that the implementation of a profile is consistent with its specification. Formal specification is needed to ensure that the implementation performs its intended operations while exhibiting desirable behaviors. The new conformance test method presented is based upon the System of Communicating Machine model which uses a formal protocol specification to generate a test sequence. The major contribution of this thesis is the application of the System of Communicating Machine model to formal profile specifications of the Survivable Adaptable Fiber Optic Embedded Network (SAFENET) standard which results in the derivation of test sequences for a SAFENET profile. The results applying this new method to SAFENET's OSI and Lightweight profiles are presented.
Group III-arsenide-nitride long wavelength laser diodes
NASA Astrophysics Data System (ADS)
Coldren, Christopher W.
Semiconductor laser diodes transmitting data over silica optical fiber form the backbone of modern day communications systems, enabling terabit per second data transmission over hundreds to thousands of kilometers of distance. The wavelength of emission of the transmission semiconductor laser diode is a critical parameter that determines the performance of the communications system. In high performance fiber optic communications systems, lasers emitting at 1300nm and 1550nm are used because of the low loss and distortion properties of the fiber in these spectral windows. The available lasers today that operate in these fiber optic transmission windows suffer from high cost and poor performance under the typical environmental conditions and require costly and unreliable cooling systems. This dissertation presents work that demonstrates that it is possible to make lasers devices with 1300nm laser emission that are compatible with low cost and operation under extreme operating conditions. The key enabling technology developed is a novel semiconductor material based structure. A group III-Arsenide-Nitride quantum well structure was developed that can be grown expitaxially on GaAs substrates. The properties of this group III-Arsenide-Nitride structure allowed high performance edge emitting and vertical cavity surface emitting lasers to be fabricated which exhibited low threshold currents and low sensitivity to operating temperature.
Secure communications using quantum cryptography
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hughes, R.J.; Buttler, W.T.; Kwiat, P.G.
1997-08-01
The secure distribution of the secret random bit sequences known as {open_quotes}key{close_quotes} material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit ofmore » an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over {open_quotes}open{close_quotes} multi-km node-to-node optical fiber communications links is possible. We have also constructed a quantum key distribution system for free-space, line-of-sight transmission using single-photon polarization states, which is currently undergoing laboratory testing. 7 figs.« less
Benefits of the fiber optic versus the electret microphone in voice amplification.
Kyriakou, Kyriaki; Fisher, Hélène R
2013-01-01
Voice disorders that result in reduced loudness may cause difficulty in communicating, socializing and participating in occupational activities. Amplification is often recommended in order to facilitate functional communication, reduce vocal load and avoid developing maladaptive compensatory behaviours. The most common microphone used with amplification systems is the electret microphone. One alternate form of microphone is the fiber optic microphone. To examine the benefits of the fiber optic (1190S) versus the electret (M04) microphone as measured by objective and subjective parameters in the amplification of a patient's voice with reduced loudness caused by neurological and/or respiratory-based problems. Eighteen patients with vocal fold paralysis, Parkinson's disease and/or chronic obstructive pulmonary disease (COPD) participated in the study. The study contained a measurement of intensity, amplitude perturbation and signal-to-noise ratio during a sustained vowel production and a measurement of intensity during conversation with the use of the two microphones simultaneously. It also included the completion of a questionnaire indicating the patient's satisfaction with each microphone. The fiber optic (1190S) microphone had better objective acoustic performance (i.e. lower amplitude perturbation, higher signal-to-noise ratio and higher intensity) than the electret (M04) microphone. It also had better patient subjective satisfaction (i.e. less conspicuousness, more voice clarity, less acoustic feedback, more loudness and more utilization) than the electret microphone. Patients with neurological and/or respiratory-based voice problems may more confidently and frequently use the fiber optic microphone to communicate, socialize and participate in occupational activities more easily. Speech-language pathologists may more confidently use or recommend the fiber optic microphone with amplification systems. © 2012 Royal College of Speech and Language Therapists.
"Techne" and Technical Communication: Toward a Dialogue.
ERIC Educational Resources Information Center
Gordon, Jay
2002-01-01
Offers background on how the term "techne" was used up through the fourth century BCE. Discusses how modern discourse on technical communication both converges with and departs from Plato's and Aristotle's statements on the relationship between "techne" and rhetoric. Points out areas for further discussion as teachers of…
Mercer University's Graduate Certificate in Interactive Multimedia.
ERIC Educational Resources Information Center
Leonard, David C.
Although most programs in technical communication reside in English departments where the focus is on writing, rhetoric, and exposition, the graduate certificate program in interactive multimedia at Mercer University is being developed for the Technical Communication Department within the School of Engineering. As a result, many of the…
Linking Ethics and Language in the Technical Communication Classroom.
ERIC Educational Resources Information Center
Sims, Brenda R.
1993-01-01
Discusses research on ethics and technical communication and examines specific methods that writers may use to manipulate language and to present information unethically. Suggests questions designed to teach students how to analyze situations that may involve such manipulation and misrepresentation. Concludes with two case studies illustrating…
Using Corporate-Based Methods To Assess Technical Communication Programs.
ERIC Educational Resources Information Center
Faber, Brenton; Bekins, Linn; Karis, Bill
2002-01-01
Investigates methods of program assessment used by corporate learning sites and profiles value added methods as a way to both construct and evaluate academic programs in technical communication. Examines and critiques assessment methods from corporate training environments including methods employed by corporate universities and value added…
Facilitating Service Learning in the Online Technical Communication Classroom
ERIC Educational Resources Information Center
Nielsen, Danielle
2016-01-01
Drawing from the author's experience teaching online technical communication courses with an embedded service-learning component, this essay opens the discussion to the potential problems involved in designing online service-learning courses and provides practical approaches to integrating service learning into online coursework. The essay…
The Social Perspective and Pedagogy in Technical Communication.
ERIC Educational Resources Information Center
Thralls, Charlotte; Blyler, Nancy Roundy
1993-01-01
Notes that as teachers integrate social theory into the technical communication classroom, they interpret the connection between writing and culture in different ways. Describes four social pedagogies of writing--the social constructionist, the ideologic, the social cognitive, and the paralogic hermeneutic--distinguishing them by their pedagogic…
Technical Report on Tele-Communications.
ERIC Educational Resources Information Center
San Mateo County PACE Center, Redwood City, CA.
To provide background material for those interested in tele-communication in education and for those planning to implement such programs in their schools, a research study was conducted to gather information from a variety of sources including educational and technical experts, conference participation, visits to schools conducting projects, and…
How to develop and write a case for technical writing
NASA Technical Reports Server (NTRS)
Couture, B.; Goldstein, J.
1981-01-01
Case of different sizes and shapes for teaching technical writing to engineers at Wayne State University have been developed. The case approach was adopted for some assignments because sophomores and juniors lacked technical expertise and professional knowledge of the engineering world. Cases were found to be good exercises, providing realistic practice in specific writing tasks or isolating particular skills in the composing process. A special kind of case which narrates the experiences of one technical person engaged in the problem-solving process in a professional rhetorical situation was developed. This type of long, realistic fiction is called a an "holistic" case. Rather than asking students to role-play a character, an holistic case realistically encompasses the whole of the technical writing process. It allows students to experience the total communication act in which the technical task and data are fully integrated into the rhetorical situation and gives an opportunity to perform in a realistic context, using skills and knowledge required in communication on the job. It is believed that the holistic case most fully exploits the advantages of the case method for students of professional communication.
Hajjar, Hani Al; Montero, David S; Lallana, Pedro C; Vázquez, Carmen; Fracasso, Bruno
2015-02-10
In this paper, the characterization of a perfluorinated graded-index polymer optical fiber (PF-GIPOF) for a high-bitrate indoor optical wireless system is reported. PF-GIPOF is used here to interconnect different optical wireless access points that distribute optical free-space high-bitrate wireless communication cells. The PF-GIPOF channel is first studied in terms of transmission attenuation and frequency response and, in a second step, the spatial power profile distribution at the fiber output is analyzed. Both characterizations are performed under varying restricted mode launch conditions, enabling us to assess the transmission channel performance subject to potential connectorization errors within an environment where the end users may intervene by themselves on the home network infrastructure.
Polarization-independent optical wavelength filter for channel dropping applications
Deri, R.J.; Patterson, F.
1996-05-07
The polarization dependence of optical wavelength filters is eliminated by using waveguide directional couplers. Material birefringence is used to compensate for the waveguide (electromagnetic) birefringence which is the original cause of the polarization dependence. Material birefringence is introduced in a controllable fashion by replacing bulk waveguide layers by finely layered composites, such as multiple quantum wells using III-V semiconductor materials. The filter has use in wavelength-division multiplexed fiber optic communication systems. This filter has broad application for wavelength-tunable receivers in fiber optic communication links, which may be used for telecommunications, optical computer interconnect links, or fiber optic sensor systems. Since multiple-wavelength systems are increasingly being used for all of these applications, the filter is useable whenever a rapidly tunable, wavelength-filtering receiver is required. 14 figs.
Polarization-independent optical wavelength filter for channel dropping applications
Deri, Robert J.; Patterson, Frank
1996-01-01
The polarization dependence of optical wavelength filters is eliminated by using waveguide directional couplers. Material birefringence is used to compensate for the waveguide (electromagnetic) birefringence which is the original cause of the polarization dependence. Material birefringence is introduced in a controllable fashion by replacing bulk waveguide layers by finely layered composites, such as multiple quantum wells using III-V semiconductor materials. The filter has use in wavelength-division-multiplexed fiber optic communication systems. This filter has broad application for wavelength-tunable receivers in fiber optic communication links, which may be used for telecommunications, optical computer interconnect links, or fiber optic sensor systems. Since multiple-wavelength systems are increasingly being used for all of these applications, the filter is useable whenever a rapidly tunable, wavelength-filtering receiver is required.
Integration of role-playing into technical skills training: a randomized controlled trial.
Nikendei, C; Kraus, B; Schrauth, M; Weyrich, P; Zipfel, S; Herzog, W; Jünger, J
2007-11-01
Recently, efforts have been undertaken to enhance the face validity of technical skills training by introducing role-plays and standardised patients. Since little is known about the effects of role-playing with respect to the realism of a training situation and students' objective performance, we performed a randomized controlled trial. 36 medical students participated in videotaped small group skills-lab sessions on the topics of Doppler sonography and gastric tube insertion. One half of the students participated in role-plays and the other half practised without role-playing. Realism of the training situation was analysed by means of post-intervention self-selected student survey evaluations. Technical performance and patient-physician communication were assessed by independent ratings of the videotaped sessions. The physician's role was regarded to be significantly more realistic when performing role-plays. Assessment of videotaped sessions showed that practising technical skills by performing role-plays resulted in significantly better patient-physician communication whereas students' technical performance did not differ between groups. Introducing role-plays enhances the realism of technical skills training and leads to better patient-physician communication. Students do not seem to be overstrained by practising clinical technical skills using role-plays. We conclude that role-playing is a valuable method in practising technical skills.
CWRUnet--Case History of a Campus-Wide Fiber-to-the-Desktop Network.
ERIC Educational Resources Information Center
Neff, Raymond K.; Haigh, Peter J.
1992-01-01
This article describes the development at Case Western Reserve University of an all-fiber optic communications network linking 7,300 outlets (faculty offices, student residences, classrooms, libraries, and laboratories) with computer data, television, audio, facsimile, and image information services. (Author/DB)
My Forty-Year Adventure in the Wonderful World of Fiber Optics!
NASA Astrophysics Data System (ADS)
Hodara, Henri
2016-11-01
In the first part of this presentation, I review the key technology developments of the last century up to the present. These developments are what led us to the communication and information revolution. This is followed by a discussion of how the use of optical fibers brought about the fusion of these two elements and the resultant proliferation of smart phones and social networks. In the second part, I recollect some of my work in fiber optics over a period of forty years in the context of those key developments. In particular, I stress what it takes for a company small in comparison to the giants in the field to capture niche markets. I also discuss the criteria that are needed to justify the application of a new technology like optical fibers to existing communication and sensing systems, and make it cost effective. I end this presentation with a few personal considerations regarding technology developments and innovation.
NASA Astrophysics Data System (ADS)
Dalarmelina, Carlos A.; Adegbite, Saheed A.; Pereira, Esequiel da V.; Nunes, Reginaldo B.; Rocha, Helder R. O.; Segatto, Marcelo E. V.; Silva, Jair A. L.
2017-05-01
Block-level detection is required to decode what may be classified as selective control information (SCI) such as control format indicator in 4G-long-term evolution systems. Using optical orthogonal frequency division multiplexing over radio-over-fiber (RoF) links, we report the experimental evaluation of an SCI detection scheme based on a time-domain correlation (TDC) technique in comparison with the conventional maximum likelihood (ML) approach. When compared with the ML method, it is shown that the TDC method improves detection performance over both 20 and 40 km of standard single mode fiber (SSMF) links. We also report a performance analysis of the TDC scheme in noisy visible light communication channel models after propagation through 40 km of SSMF. Experimental and simulation results confirm that the TDC method is attractive for practical orthogonal frequency division multiplexing-based RoF and fiber-wireless systems. Unlike the ML method, another key benefit of the TDC is that it requires no channel estimation.
Drop-in compatible entanglement for optical-fiber networks.
Hall, Matthew A; Altepeter, Joseph B; Kumar, Prem
2009-08-17
A growing number of quantum communication protocols require entanglement distribution among remote parties, which is best accomplished by exploiting the mature technology and extensive infrastructure of low-loss optical fiber. For this reason, a practical source of entangled photons must be drop-in compatible with optical fiber networks. Here we demonstrate such a source for the first time, in which the nonlinearity of standard single-mode fiber is utilized to yield entangled photon pairs in the 1310-nm O-band. Using an ultra-stable design, we produce polarization entanglement with 98.0% +/- 0.5% fidelity to a maximally entangled state as characterized via coincidence-basis tomography. To demonstrate the source's drop-in capability, we transmit one photon from each entangled pair through a telecommunications-grade optical amplifier set to boost classical 1550-nm (C-band) communication signals. We verify that the photon pairs experience no measurable decoherence upon passing through the active amplifier (the output state's fidelity with a maximally entangled state is 98.4% +/- 1.4%). (c) 2009 Optical Society of America
Single-mode optical fiber design with wide-band ultra low bending-loss for FTTH application.
Watekar, Pramod R; Ju, Seongmin; Han, Won-Taek
2008-01-21
We propose a new design of a single-mode optical fiber (SMF) which exhibits ultra low bend sensitivity over a wide communication band (1.3 microm to 1.65 microm). A five-cladding fiber structure has been proposed to minimize the bending loss, estimated to be as low as 4.4x10(-10) dB/turn for the bend radius of 10 mm.
[Carbon fiber-reinforced plastics as implant materials].
Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R
2003-01-01
Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.
ERIC Educational Resources Information Center
Society for Technical Communication, Washington, DC.
Prepared by representatives of government, business, industry, and education, the papers in this compilation deal with a variety of aspects of technical communication. The approximately 150 papers are arranged according to the following categories: advanced technology applications, graphics and production, management and professional development,…
Conducting Research in Technical Communication: The Application of True Experimental Designs.
ERIC Educational Resources Information Center
Spyridakis, Jan H.
1992-01-01
Explains the use of true experimental designs in technical communication research, lists the eight steps in the research process, and concludes with the hope that practitioners should now be able to read research studies critically and perhaps design empirical studies of their own after further reading. (SR)
Meeting Students Where They Are: Advancing a Theory and Practice of Archives in the Classroom
ERIC Educational Resources Information Center
Saidy, Christina; Hannah, Mark; Sura, Tom
2011-01-01
This article uses theories of technical communication and archives to advance a pedagogy that includes archival production in the technical communication classroom. By developing and maintaining local classroom archives, students directly engage in valuable processes of appraisal, selection, collaboration, and retention. The anticipated outcomes…
ERIC Educational Resources Information Center
Bhattacharyya, Ena; Patil, Arun; Sargunan, Rajeswary Appacutty
2010-01-01
Engineering communication studies indicate the importance of oral presentations as an indispensable component of workplace oral communication activities; however, since there is limited literature regarding stakeholder perceptions of effective presentation skills and attributes in technical oral presentations or final year engineering project…
29 CFR 93.205 - Professional and technical services.
Code of Federal Regulations, 2010 CFR
2010-07-01
.... However, communications with the intent to influence made by a professional (such as a licensed lawyer) or... section because the lawyer is not providing professional legal services. Similarly, communications with... 29 Labor 1 2010-07-01 2010-07-01 true Professional and technical services. 93.205 Section 93.205...
Theorycrafting the Classroom: Constructing the Introductory Technical Communication Course as a Game
ERIC Educational Resources Information Center
Finseth, Carly
2015-01-01
When games are approached as a pedagogical methodology, the homologies between games and technical communication are highlighted: pedagogy that teaches people to play and succeed within certain confines; classroom assessment that provides meaningful feedback to encourage self-improvement; instructional design that incorporates gaming theory and…
Outsiders Looking In: Tutor Expertise in Engineering Writing
ERIC Educational Resources Information Center
Bengesai, Annah
2015-01-01
Drawing on an academic literacies approach, this article explores the representations of technical communication by non-content expert tutors teaching the Technical Communication for Engineering course at a South African university. The course is offered to all first year engineering students as a developmental academic literacy course. It is…
ERIC Educational Resources Information Center
Garrison, Kevin
2014-01-01
Technical communication's attempt to prioritize theories of scholarship and pedagogy has resulted in several authors contributing a three-dimensional framework to approach technology: the instrumental perspective, the critical humanist perspective, and the user-centered perspective [1-3]. This article traces connections between this framework for…
Using Design Principles to Teach Technical Communication.
ERIC Educational Resources Information Center
Markel, Mike
1995-01-01
Compares the writing of two students--a competent writer and a weak one--in a technical communication course before and after discussion of design principles. Finds that a basic understanding of design principles helped them improve document macrostructure but had little effect on document microstructure. Suggests that integrating document design…
Technical Communications in OSS Content Management Systems: An Academic Institutional Case Study
ERIC Educational Resources Information Center
Cripps, Michael J.
2011-01-01
Single sourcing through a content management system (CMS) is altering technical communication practices in many organizations, including institutions of higher education. Open source software (OSS) solutions are currently among the most popular content management platforms adopted by colleges and universities in the United States and abroad. The…
ERIC Educational Resources Information Center
Ohio State Dept. of Education, Columbus. Div. of Career-Technical and Adult Education.
This document contains an introduction to the Ohio Integrated Technical and Academic Competency (ITAC) and Specialization ITAC; an overview of the visual communications art profession; a list acknowledging professionals who helped develop the competency list; and the comprehensive list of the professional or occupational competencies deemed…
A Bit More to It: Scholarly Communication Forums as Socio-Technical Interaction Networks.
ERIC Educational Resources Information Center
Kling, Rob; McKim, Geoffrey; King, Adam
2003-01-01
Examines the conceptual models that help to understand the development and sustainability of scholarly and professional communication forums on the Internet. An alternative information processing model that considers information technologies as Socio-Technical Interaction Networks (STINs) and a method for modeling electronic forums as STINs are…
Space lab system analysis: Advanced Solid Rocket Motor (ASRM) communications networks analysis
NASA Technical Reports Server (NTRS)
Ingels, Frank M.; Moorhead, Robert J., II; Moorhead, Jane N.; Shearin, C. Mark; Thompson, Dale R.
1990-01-01
A synopsis of research on computer viruses and computer security is presented. A review of seven technical meetings attended is compiled. A technical discussion on the communication plans for the ASRM facility is presented, with a brief tutorial on the potential local area network media and protocols.
CATV: The New Communicator. 21st Annual NCTA Convention Official Transcript. Technical Volume.
ERIC Educational Resources Information Center
National Cable Television Association, Inc., Washington, DC.
The proceedings of the 21st annual National Cable Television Association convention are presented under the following groupings: short haul microwave systems, satellite/cable system engineering, market studies, FCC (Federal Communications Commission) technical rules and standards, program origination, cable channel allocations, cable system…
Statistical Indicators of Scientific and Technical Communication (1960-1980), 1977 Edition.
ERIC Educational Resources Information Center
King, D. W.; And Others
This report describes results of the second year of research in developing statistical indicators of scientific and technical communication. This effort placed special emphasis on the periodical literature including new estimates of the number of journals and other periodicals, characteristics of journals, journal prices, number of subscribers,…
ERIC Educational Resources Information Center
Ohio State Dept. of Education, Columbus. Div. of Career-Technical and Adult Education.
This document contains an introduction to the Ohio Integrated Technical and Academic Competency (ITAC) and Specialization ITAC; an overview of the graphic communications field; a list acknowledging professionals who helped develop the competency list; and a comprehensive list of the professional or occupational competencies deemed essential for…
Koike-Akino, Toshiaki; Duan, Chunjie; Parsons, Kieran; Kojima, Keisuke; Yoshida, Tsuyoshi; Sugihara, Takashi; Mizuochi, Takashi
2012-07-02
Fiber nonlinearity has become a major limiting factor to realize ultra-high-speed optical communications. We propose a fractionally-spaced equalizer which exploits a trained high-order statistics to deal with data-pattern dependent nonlinear impairments in fiber-optic communications. The computer simulation reveals that the proposed 3-tap equalizer improves Q-factor by more than 2 dB for long-haul transmissions of 5,230 km distance and 40 Gbps data rate. We also demonstrate that the joint use of a digital backpropagation (DBP) and the proposed equalizer offers an additional 1-2 dB performance improvement due to the channel shortening gain. A performance in high-speed transmissions of 100 Gbps and beyond is evaluated as well.
Multidisciplinary crisis simulations: the way forward for training surgical teams.
Undre, Shabnam; Koutantji, Maria; Sevdalis, Nick; Gautama, Sanjay; Selvapatt, Nowlan; Williams, Samantha; Sains, Parvinderpal; McCulloch, Peter; Darzi, Ara; Vincent, Charles
2007-09-01
High-reliability organizations have stressed the importance of non-technical skills for safety and of regularly providing such training to their teams. Recently safety skills training has been applied in the practice of medicine. In this study, we developed and piloted a module using multidisciplinary crisis scenarios in a simulated operating theatre to train entire surgical teams. Twenty teams participated (n = 80); each consisted of a trainee surgeon, anesthetist, operating department practitioner (ODP), and scrub nurse. Crisis scenarios such as difficult intubation, hemorrhage, or cardiac arrest were simulated. Technical and non-technical skills (leadership, communication, team skills, decision making, and vigilance), were assessed by clinical experts and by two psychologists using relevant technical and human factors rating scales. Participants received technical and non-technical feedback, and the whole team received feedback on teamwork. Trainees assessed the training favorably. For technical skills there were no differences between surgical trainees' assessment scores and the assessment scores of the trainers. However, nurses overrated their technical skill. Regarding non-technical skills, leadership and decision making were scored lower than the other three non-technical skills (communication, team skills, and vigilance). Surgeons scored lower than nurses on communication and teamwork skills. Surgeons and anesthetists scored lower than nurses on leadership. Multidisciplinary simulation-based team training is feasible and well received by surgical teams. Non-technical skills can be assessed alongside technical skills, and differences in performance indicate where there is a need for further training. Future work should focus on developing team performance measures for training and on the development and evaluation of systematic training for technical and non-technical skills to enhance team performance and safety in surgery.
NASA Technical Reports Server (NTRS)
Barclay, Rebecca O.; Pinelli, Thomas E.
1997-01-01
The large and complex aerospace industry, which employed approximately 850,000 people in 1994 (Aerospace Facts, 1994-95, p. 11), plays a vital role in the nation's economy. Although only a small percentage of those employed in aerospace are technical communicators, they perform a wide variety of communication duties in government and the private sector.
Free-space quantum cryptography with quantum and telecom communication channels
NASA Astrophysics Data System (ADS)
Toyoshima, Morio; Takayama, Yoshihisa; Klaus, Werner; Kunimori, Hiroo; Fujiwara, Mikio; Sasaki, Masahide
2008-07-01
Quantum cryptography is a new technique that uses the laws of physics to transmit information securely. In such systems, the vehicle to transfer quantum information is a single photon. However, the transmission distance is limited by the absorption of photons in an optical fiber in which the maximum demonstrated range is about 100 km. Free-space quantum cryptography between a ground station and a satellite is a way of sending the quantum information further distances than that with optical fibers since there is no birefringence effect in the atmosphere. At the National Institute of Information and Communications Technology (NICT), the laser communication demonstration between the NICT optical ground station and a low earth orbit satellite was successfully conducted in 2006. For such space communication links, free-space quantum cryptography is considered to be an important application in the future. We have developed a prototype system for free-space quantum cryptography using a weak coherent light and a telecom communication channel. The preliminary results are presented.
Pirnejad, Habibollah; Bal, Roland; Stoop, Arjen P.; Berg, Marc
2007-01-01
Background To afford efficient and high quality care, healthcare providers increasingly need to exchange patient data. The existence of a communication network amongst care providers will help them to exchange patient data more efficiently. Information and communication technology (ICT) has much potential to facilitate the development of such a communication network. Moreover, in order to offer integrated care interoperability of healthcare organizations based upon the exchanged data is of crucial importance. However, complications around such a development are beyond technical impediments. Objectives To determine the challenges and complexities involved in building an Inter-organisational Communication network (IOCN) in healthcare and the appropriations in the strategies. Case study Interviews, literature review, and document analysis were conducted to analyse the developments that have taken place toward building a countrywide electronic patient record and its challenges in The Netherlands. Due to the interrelated nature of technical and non-technical problems, a socio-technical approach was used to analyse the data and define the challenges. Results Organisational and cultural changes are necessary before technical solutions can be applied. There are organisational, financial, political, and ethicolegal challenges that have to be addressed appropriately. Two different approaches, one “centralised” and the other “decentralised” have been used by Dutch healthcare providers to adopt the necessary changes and cope with these challenges. Conclusion The best solutions in building an IOCN have to be drawn from both the centralised and the decentralised approaches. Local communication initiatives have to be supervised and supported centrally and incentives at the organisations' interest level have to be created to encourage the stakeholder organisations to adopt the necessary changes. PMID:17627296
Pirnejad, Habibollah; Bal, Roland; Stoop, Arjen P; Berg, Marc
2007-05-16
To afford efficient and high quality care, healthcare providers increasingly need to exchange patient data. The existence of a communication network amongst care providers will help them to exchange patient data more efficiently. Information and communication technology (ICT) has much potential to facilitate the development of such a communication network. Moreover, in order to offer integrated care interoperability of healthcare organizations based upon the exchanged data is of crucial importance. However, complications around such a development are beyond technical impediments. To determine the challenges and complexities involved in building an Inter-organisational Communication network (IOCN) in healthcare and the appropriations in the strategies. Interviews, literature review, and document analysis were conducted to analyse the developments that have taken place toward building a countrywide electronic patient record and its challenges in The Netherlands. Due to the interrelated nature of technical and non-technical problems, a socio-technical approach was used to analyse the data and define the challenges. Organisational and cultural changes are necessary before technical solutions can be applied. There are organisational, financial, political, and ethicolegal challenges that have to be addressed appropriately. Two different approaches, one "centralised" and the other "decentralised" have been used by Dutch healthcare providers to adopt the necessary changes and cope with these challenges. The best solutions in building an IOCN have to be drawn from both the centralised and the decentralised approaches. Local communication initiatives have to be supervised and supported centrally and incentives at the organisations' interest level have to be created to encourage the stakeholder organisations to adopt the necessary changes.
Direct Integration of Dynamic Emissive Displays into Knitted Fabric Structures
NASA Astrophysics Data System (ADS)
Bellingham, Alyssa
Smart textiles are revolutionizing the textile industry by combining technology into fabric to give clothing new abilities including communication, transformation, and energy conduction. The advent of electroluminescent fibers, which emit light in response to an applied electric field, has opened the door for fabric-integrated emissive displays in textiles. This thesis focuses on the development of a flexible and scalable emissive fabric display with individually addressable pixels disposed within a fabric matrix. The pixels are formed in areas where a fiber supporting the dielectric and phosphor layers of an electroluminescent structure contacts a conductive surface. This conductive surface can be an external conductive fiber, yarn or wire, or a translucent conductive material layer deposited at set points along the electroluminescent fibers. Different contacting methods are introduced and the different ways the EL yarns can be incorporated into the knitted fabric are discussed. EL fibers were fabricated using a single yarn coating system with a custom, adjustable 3D printed slot die coater for even distribution of material onto the supporting fiber substrates. These fibers are mechanically characterized inside of and outside of a knitted fabric matrix to determine their potential for various applications, including wearables. A 4-pixel dynamic emissive display prototype is fabricated and characterized. This is the first demonstration of an all-knit emissive display with individually controllable pixels. The prototype is composed of a grid of fibers supporting the dielectric and phosphor layers of an electroluminescent (EL) device structure, called EL fibers, and conductive fibers acting as the top electrode. This grid is integrated into a biaxial weft knit structure where the EL fibers make up the rows and conductive fibers make up the columns of the reinforcement yarns inside the supporting weft knit. The pixels exist as individual segments of electroluminescence that occur where the conductive fibers contact the EL fibers. A passive matrix addressing scheme was used to apply a voltage to each pixel individually, creating a display capable of dynamically communicating information. Optical measurements of the intensity and color of emitted light were used to quantify the performance of the display and compare it to state-of-the-art display technologies. The charge-voltage (Q-V) electrical characterization technique is used to gain information about the ACPEL fiber device operation, and mechanical tests were performed to determine the effect everyday wear and tear would have on the performance of the display. The presented textile display structure and method of producing fibers with individual sections of electroluminescence addresses the shortcomings in existing textile display technology and provides a route to directly integrated communicative textiles for applications ranging from biomedical research and monitoring to fashion. An extensive discussion of the materials and methods of production needed to scale this textile display technology and incorporate it into wearable applications is presented.
Evaluation of ionic liquid treated sisal (agave sisalana) fiber as sorbent in biodiesel spill
NASA Astrophysics Data System (ADS)
Costa, E.; Silva, A.; Mattedi, S.
2018-04-01
The global economic development continually demands the use of energy resources, among which various types of oils are widely used. Despite their undeniable economic importance, environmental accidents with these occur frequently. Thus, the search for efficient and low-cost mitigating measures is recurrent. In this context, techniques that use natural adsorbents, such as vegetable fibers, have been studied, since they combine efficiency, selectivity, low cost and sustainability. Studies have been carried out using various types of fibers, natural or chemically treated. The interest in treating the fiber lies in the fact that, changing the chemical structure of the fiber, its oil sorption capacity is increased. Due to the offered advantages, an alternative and promising type of surface treatment using ionic liquids was performed, to the detriment of traditional treatments. Thus, the technical feasibility of the use of sisal fiber treated with ionic liquid for adsorption of biodiesel was studied.
Fiber optic combiner and duplicator
NASA Technical Reports Server (NTRS)
1979-01-01
The investigation of the possible development of two optical devices, one to take two images as inputs and to present their arithmetic sum as a single output, the other to take one image as input and present two identical images as outputs is described. Significant engineering time was invested in establishing precision fiber optics drawing capabilities, real time monitoring of the fiber size and exact measuring of fiber optics ribbons. Various assembly procedures and tooling designs were investigated and prototype models were built and evaluated that established technical assurance that the device was feasible and could be fabricated. Although the interleaver specification in its entirety was not achieved, the techniques developed in the course of the program improved the quality of images transmitted by fiber optic arrays by at least an order of magnitude. These techniques are already being applied to the manufacture of precise fiber optic components.
Experimental results of 5-Gbps free-space coherent optical communications with adaptive optics
NASA Astrophysics Data System (ADS)
Chen, Mo; Liu, Chao; Rui, Daoman; Xian, Hao
2018-07-01
In a free-space optical communication system with fiber optical components, the received signal beam must be coupled into a single-mode fiber (SMF) before being amplified and detected. The impacts analysis of tracking errors and wavefront distortion on SMF coupling show that under the condition of relatively strong turbulence, only the tracking errors compensation is not enough, and turbulence wavefront aberration is required to be corrected. Based on our previous study and design of SMF coupling system with a 137-element continuous surface deformable mirror AO unit, we perform an experiment of a 5-Gbps Free-space Coherent Optical Communication (FSCOC) system, in which the eye pattern and Bit-error Rate (BER) are displayed. The comparative results are shown that the influence of the atmospheric is fatal in FSCOC systems. The BER of coherent communication is under 10-6 with AO compensation, which drops significantly compared with the BER without AO correction.
Multigigabit optical transceivers for high-data rate military applications
NASA Astrophysics Data System (ADS)
Catanzaro, Brian E.; Kuznia, Charlie
2012-01-01
Avionics has experienced an ever increasing demand for processing power and communication bandwidth. Currently deployed avionics systems require gigabit communication using opto-electronic transceivers connected with parallel optical fiber. Ultra Communications has developed a series of transceiver solutions combining ASIC technology with flip-chip bonding and advanced opto-mechanical molded optics. Ultra Communications custom high speed ASIC chips are developed using an SoS (silicon on sapphire) process. These circuits are flip chip bonded with sources (VCSEL arrays) and detectors (PIN diodes) to create an Opto-Electronic Integrated Circuit (OEIC). These have been combined with micro-optics assemblies to create transceivers with interfaces to standard fiber array (MT) cabling technology. We present an overview of the demands for transceivers in military applications and how new generation transceivers leverage both previous generation military optical transceivers as well as commercial high performance computing optical transceivers.
Commercialized VCSEL components fabricated at TrueLight Corporation
NASA Astrophysics Data System (ADS)
Pan, Jin-Shan; Lin, Yung-Sen; Li, Chao-Fang A.; Chang, C. H.; Wu, Jack; Lee, Bor-Lin; Chuang, Y. H.; Tu, S. L.; Wu, Calvin; Huang, Kai-Feng
2001-05-01
TrueLight Corporation was found in 1997 and it is the pioneer of VCSEL components supplier in Taiwan. We specialize in the production and distribution of VCSEL (Vertical Cavity Surface Emitting Laser) and other high-speed PIN-detector devices and components. Our core technology is developed to meet blooming demand of fiber optic transmission. Our intention is to diverse the device application into data communication, telecommunication and industrial markets. One mission is to provide the high performance, highly reliable and low-cost VCSEL components for data communication and sensing applications. For the past three years, TrueLight Corporation has entered successfully into the Gigabit Ethernet and the Fiber Channel data communication area. In this paper, we will focus on the fabrication of VCSEL components. We will present you the evolution of implanted and oxide-confined VCSEL process, device characterization, also performance in Gigabit data communication and the most important reliability issue
Hollow fiber apparatus and use thereof for fluids separations and heat and mass transfers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bikson, Benjamin; Etter, Stephen; Ching, Nathaniel
A hollow fiber device includes a hollow fiber bundle, comprising a plurality of hollow fibers, a first tubesheet and a second tubesheet encapsulating respective distal ends of the hollow fiber bundle. The tubesheets have boreholes in fluid communication with bores of the hollow fibers. In at least one of the tubesheets, the boreholes are formed radially. The hollow fiber device can be utilized in heat exchange, in gas/gas, liquid/liquid and gas/liquid heat transfer, in combined heat and mass transfer and in fluid separation assemblies and processes. The design disclosed herein is light weight and compact and is particularly advantageous whenmore » the pressure of a first fluid introduced into the bores of hollow fibers is higher than the pressure on the shell side of the device.« less
Engineering quantum communication systems
NASA Astrophysics Data System (ADS)
Pinto, Armando N.; Almeida, Álvaro J.; Silva, Nuno A.; Muga, Nelson J.; Martins, Luis M.
2012-06-01
Quantum communications can provide almost perfect security through the use of quantum laws to detect any possible leak of information. We discuss critical issues in the implementation of quantum communication systems over installed optical fibers. We use stimulated four-wave mixing to generate single photons inside optical fibers, and by tuning the separation between the pump and the signal we adjust the average number of photons per pulse. We report measurements of the source statistics and show that it goes from a thermal to Poisson distribution with the increase of the pump power. We generate entangled photons pairs through spontaneous four-wave mixing. We report results for different type of fibers to approach the maximum value of the Bell inequality. We model the impact of polarization rotation, attenuation and Raman scattering and present optimum configurations to increase the degree of entanglement. We encode information in the photons polarization and assess the use of wavelength and time division multiplexing based control systems to compensate for the random rotation of the polarization during transmission. We show that time division multiplexing systems provide a more robust solution considering the values of PMD of nowadays installed fibers. We evaluate the impact on the quantum channel of co-propagating classical channels, and present guidelines for adding quantum channels to installed WDM optical communication systems without strongly penalizing the performance of the quantum channel. We discuss the process of retrieving information from the photons polarization. We identify the major impairments that limit the speed and distance of the quantum channel. Finally, we model theoretically the QBER and present results of an experimental performance assessment of the system quality through QBER measurements.
Optical Material Researches for Frontier Optical Ceramics and Visible Fiber Laser Technologies
2016-07-07
zeolite method”, Motoichiro Murakami, Yasushi Fujimoto, Shinji Motokoshi, Tatsuhiro Sato, Hiroyuki Shiraga, Optics Communications 328 (2014) pp.121...Center, Shanghai, China. 13) “Rare Earth Doped Fiber Lasers Based on Zeolite Method - (invited)”, Y. Fujimoto, The 4th International Workshop on
Single-mode fiber systems for deep space communication network
NASA Technical Reports Server (NTRS)
Lutes, G.
1982-01-01
The present investigation is concerned with the development of single-mode optical fiber distribution systems. It is pointed out that single-mode fibers represent potentially a superior medium for the distribution of frequency and timing reference signals and wideband (400 MHz) IF signals. In this connection, single-mode fibers have the potential to improve the capability and precision of NASA's Deep Space Network (DSN). Attention is given to problems related to precise time synchronization throughout the DSN, questions regarding the selection of a transmission medium, and the function of the distribution systems, taking into account specific improvements possible by an employment of single-mode fibers.
Robust transmission of non-Gaussian entanglement over optical fibers
NASA Astrophysics Data System (ADS)
Biswas, Asoka; Lidar, Daniel A.
2006-12-01
We show how the entanglement in a wide range of continuous variable non-Gaussian states can be preserved against decoherence for long-range quantum communication through an optical fiber. We apply protection via decoherence-free subspaces and quantum dynamical decoupling to this end. The latter is implemented by inserting phase shifters at regular intervals Δ inside the fiber, where Δ is roughly the ratio of the speed of light in the fiber to the bath high-frequency cutoff. Detailed estimates of relevant parameters are provided using the boson-boson model of system-bath interaction for silica fibers and Δ is found to be on the order of a millimeter.
VLT instruments: industrial solutions for non-scientific detector systems
NASA Astrophysics Data System (ADS)
Duhoux, P.; Knudstrup, J.; Lilley, P.; Di Marcantonio, P.; Cirami, R.; Mannetta, M.
2014-07-01
Recent improvements in industrial vision technology and products together with the increasing need for high performance, cost efficient technical detectors for astronomical instrumentation have led ESO with the contribution of INAF to evaluate this trend and elaborate ad-hoc solutions which are interoperable and compatible with the evolution of VLT standards. The ESPRESSO spectrograph shall be the first instrument deploying this technology. ESO's Technical CCD (hereafter TCCD) requirements are extensive and demanding. A lightweight, low maintenance, rugged and high performance TCCD camera product or family of products is required which can operate in the extreme environmental conditions present at ESO's observatories with minimum maintenance and minimal downtime. In addition the camera solution needs to be interchangeable between different technical roles e.g. slit viewing, pupil and field stabilization, with excellent performance characteristics under a wide range of observing conditions together with ease of use for the end user. Interoperability is enhanced by conformance to recognized electrical, mechanical and software standards. Technical requirements and evaluation criteria for the TCCD solution are discussed in more detail. A software architecture has been adopted which facilitates easy integration with TCCD's from different vendors. The communication with the devices is implemented by means of dedicated adapters allowing usage of the same core framework (business logic). The preference has been given to cameras with an Ethernet interface, using standard TCP/IP based communication. While the preferred protocol is the industrial standard GigE Vision, not all vendors supply cameras with this interface, hence proprietary socket-based protocols are also acceptable with the provision of a validated Linux compliant API. A fundamental requirement of the TCCD software is that it shall allow for a seamless integration with the existing VLT software framework. ESPRESSO is a fiber-fed, cross-dispersed echelle spectrograph that will be located in the Combined-Coudé Laboratory of the VLT in the Paranal Observatory in Chile. It will be able to operate either using the light of any of the UT's or using the incoherently combined light of up to four UT's. The stabilization of the incoming beam is achieved by dedicated piezo systems controlled via active loops closed on 4 + 4 dedicated TCCD's for the stabilization of the pupil image and of the field with a frequency goal of 3 Hz on a 2nd to 3rd magnitude star. An additional 9th TCCD system shall be used as an exposure-meter. In this paper we will present the technical CCD solution for future VLT instruments.
Rugged fiber optic probe for raman measurement
O'Rourke, Patrick E.; Toole, Jr., William R.; Nave, Stanley E.
1998-01-01
An optical probe for conducting light scattering analysis is disclosed. The probe comprises a hollow housing and a probe tip. A fiber assembly made up of a transmitting fiber and a receiving bundle is inserted in the tip. A filter assembly is inserted in the housing and connected to the fiber assembly. A signal line from the light source and to the spectrometer also is connected to the filter assembly and communicates with the fiber assembly. By using a spring-loaded assembly to hold the fiber connectors together with the in-line filters, complex and sensitive alignment procedures are avoided. The close proximity of the filter assembly to the probe tip eliminates or minimizes self-scattering generated by the optical fiber. Also, because the probe can contact the sample directly, sensitive optics can be eliminated.
Design of fiber optic probes for laser light scattering
NASA Technical Reports Server (NTRS)
Dhadwal, Harbans S.; Chu, Benjamin
1989-01-01
A quantitative analysis is presented of the role of optical fibers in laser light scattering. Design of a general fiber optic/microlens probe by means of ray tracing is described. Several different geometries employing an optical fiber of the type used in lightwave communications and a graded index microlens are considered. Experimental results using a nonimaging fiber optic detector probe show that due to geometrical limitations of single mode fibers, a probe using a multimode optical fiber has better performance, for both static and dynamic measurements of the scattered light intensity, compared with a probe using a single mode fiber. Fiber optic detector probes are shown to be more efficient at data collection when compared with conventional approaches to measurements of the scattered laser light. Integration of fiber optic detector probes into a fiber optic spectrometer offers considerable miniaturization of conventional light scattering spectrometers, which can be made arbitrarily small. In addition static and dynamic measurements of scattered light can be made within the scattering cell and consequently very close to the scattering center.
60-GHz Millimeter-wave Over Fiber with Directly Modulated Dual-mode Laser Diode
Tsai, Cheng-Ting; Lin, Chi-Hsiang; Lin, Chun-Ting; Chi, Yu-Chieh; Lin, Gong-Ru
2016-01-01
A directly modulated dual-mode laser diode (DMLD) with third-order intermodulation distortion (IMD3) suppression is proposed for a 60-GHz millimeter-wave over fiber (MMWoF) architecture, enabling new fiber-wireless communication access to cover 4-km single-mode-fiber (SMF) and 3-m wireless 16-QAM OFDM transmissions. By dual-mode injection-locking, the throughput degradation of the DMLD is mitigated with saturation effect to reduce its threshold, IMD3 power and relative intensity noise to 7.7 mA, −85 dBm and −110.4 dBc/Hz, respectively, providing huge spurious-free dynamic range of 85.8 dB/Hz2/3. This operation suppresses the noise floor of the DMLD carried QPSK-OFDM spectrum by 5 dB. The optical receiving power is optimized to restrict the power fading effect for improving the bit error rate to 1.9 × 10−3 and the receiving power penalty to 1.1 dB. Such DMLD based hybrid architecture for 60-GHz MMW fiber-wireless access can directly cover the current optical and wireless networks for next-generation indoor and short-reach mobile communications. PMID:27297267
Generating broadband vortex modes in ring-core fiber by using a plasmonic q-plate.
Ye, Jingfu; Li, Yan; Han, Yanhua; Deng, Duo; Su, Xiaoya; Song, He; Gao, Jianmin; Qu, Shiliang
2017-08-15
A mode convertor was proposed and investigated for generating vortex modes in a ring-core fiber based on a plasmonic q-plate (PQP), which is composed of specially organized L-shaped resonator (LSR) arrays. A multicore fiber was used to transmit fundamental modes, and the LSR arrays were used to modulate phases of these fundamental modes. Behind the PQP, the transmitted fundamental modes with gradient phase distribution can be considered as the incident lights for generating broadband vortex modes in the ring-core fiber filter. The topological charges of generated vortex modes can be various by using an optical PQP with different q, and the chirality of the generated vortex mode can be controlled by the sign of q and handedness of the incident circularly polarized light. The operation bandwidth is 800 nm in the range of 1200-2000 nm, which covers six communication bands from the O band to the U band. The separation of vortex modes also was addressed by using a dual ring-core fiber. The mode convertor is of potential interest for connecting a traditional network and vortex communication network.
Spectral Properties of Er3+/Tm3+ Co-Doped ZBLAN Glasses and Fibers
Liao, Xili; Jiang, Xiaobo; Yang, Qiuhong; Wang, Longfei; Chen, Danping
2017-01-01
A series of Er3+/Tm3+ co-doped fluoride (ZBLAN) glasses and fibers was prepared and their fluorescence spectra was measured under excitation at 793 nm and 980 nm. Correlation between the self-absorption effect of rare-earth ions and the shift of the emission peak was investigated. With the increasing length of fiber, the emission peaks red-shift when self-absorption occurs at the upper level of emission transition or blue-shift when that occurs at the lower level. As a result of the strong self-absorption effect, Er3+/Tm3+ co-doped fibers mainly yield 1390–1470, 1850–1980, and 2625–2750 nm emissions when excited at 793 nm, and 1480–1580, 1800–1980, and 2625–2750 nm emissions when excited at 980 nm. Further, a broadband emission in the range of 1410–1580 nm covering the S + C communication band was obtained by the dual-pumping scheme of 793 nm and 980 nm. Results suggest that the dual-pumping scheme would be more effective and important for an Er3+/Tm3+ co-doped fiber amplifier working in the S + C communication band. PMID:28772846
Spectral Properties of Er3+/Tm3+ Co-Doped ZBLAN Glasses and Fibers.
Liao, Xili; Jiang, Xiaobo; Yang, Qiuhong; Wang, Longfei; Chen, Danping
2017-05-03
A series of Er 3+ /Tm 3+ co-doped fluoride (ZBLAN) glasses and fibers was prepared and their fluorescence spectra was measured under excitation at 793 nm and 980 nm. Correlation between the self-absorption effect of rare-earth ions and the shift of the emission peak was investigated. With the increasing length of fiber, the emission peaks red-shift when self-absorption occurs at the upper level of emission transition or blue-shift when that occurs at the lower level. As a result of the strong self-absorption effect, Er 3+ /Tm 3+ co-doped fibers mainly yield 1390-1470, 1850-1980, and 2625-2750 nm emissions when excited at 793 nm, and 1480-1580, 1800-1980, and 2625-2750 nm emissions when excited at 980 nm. Further, a broadband emission in the range of 1410-1580 nm covering the S + C communication band was obtained by the dual-pumping scheme of 793 nm and 980 nm. Results suggest that the dual-pumping scheme would be more effective and important for an Er 3+ /Tm 3+ co-doped fiber amplifier working in the S + C communication band.
COOP 3D ARPA Experiment 109 National Center for Atmospheric Research
NASA Technical Reports Server (NTRS)
1998-01-01
Coupled atmospheric and hydrodynamic forecast models were executed on the supercomputing resources of the National Center for Atmospheric Research (NCAR) in Boulder, Colorado and the Ohio Supercomputing Center (OSC)in Columbus, Ohio. respectively. The interoperation of the forecast models on these geographically diverse, high performance Cray platforms required the transfer of large three dimensional data sets at very high information rates. High capacity, terrestrial fiber optic transmission system technologies were integrated with those of an experimental high speed communications satellite in Geosynchronous Earth Orbit (GEO) to test the integration of the two systems. Operation over a spacecraft in GEO orbit required modification of the standard configuration of legacy data communications protocols to facilitate their ability to perform efficiently in the changing environment characteristic of a hybrid network. The success of this performance tuning enabled the use of such an architecture to facilitate high data rate, fiber optic quality data communications between high performance systems not accessible to standard terrestrial fiber transmission systems. Thus obviating the performance degradation often found in contemporary earth/satellite hybrids.
Underwater fiber-wireless communication with a passive front end
NASA Astrophysics Data System (ADS)
Xu, Jing; Sun, Bin; Lyu, Weichao; Kong, Meiwei; Sarwar, Rohail; Han, Jun; Zhang, Wei; Deng, Ning
2017-11-01
We propose and experimentally demonstrate a novel concept on underwater fiber-wireless (Fi-Wi) communication system with a fully passive wireless front end. A low-cost step-index (SI) plastic optical fiber (POF) together with a passive collimating lens at the front end composes the underwater Fi-Wi architecture. We have achieved a 1.71-Gb/s transmission at a mean BER of 4.97 × 10-3 (1.30 × 10-3 when using power loading) over a 50-m SI-POF and 2-m underwater wireless channel using orthogonal frequency division multiplexing (OFDM). Although the wireless part is very short, it actually plays a crucial role in practical underwater implementation, especially in deep sea. Compared with the wired solution (e.g. using a 52-m POF cable without the UWOC part), the proposed underwater Fi-Wi scheme can save optical wet-mate connectors that are sophisticated, very expensive and difficult to install in deep ocean. By combining high-capacity robust POF with the mobility and ubiquity of underwater wireless optical communication (UWOC), the proposed underwater Fi-Wi technology will find wide application in ocean exploration.
NASA Technical Reports Server (NTRS)
Pinelli, Thomas E.; Holloway, Karen; Sato, Yuko; Barclay, Rebecca O.; Kennedy, John M.
1995-01-01
To understand the diffusion of aerospace knowledge, it is necessary to understand the communications practices and the information-seeking behaviors of those involved in the production, transfer, and use of aerospace knowledge at the individual, organizational, national, and international levels. In this paper, we report selected results from a survey of Japanese and U.S. aerospace engineers and scientists that focused on communications practices and information-seeking behaviors in the workplace. Data are presented for the following topics: importance of and time spent communicating information, collaborative writing, need for an undergraduate course in technical communications, use of libraries, the use and importance of electronic (computer) networks, and the use and importance of foreign and domestically produced technical reports. The responses of the survey respondents are placed within the context of the Japanese culture. We assume that differences in Japanese and U.S. cultures influence the communications practices and information-seeking behaviors of Japanese and U.S. aerospace engineers and scientists.
NASA Astrophysics Data System (ADS)
Shukri, S. Ahmad; Millar, R. M.; Gratton, G.; Garner, M.
2016-10-01
In the world of aircraft maintenance organisation, verbal and written communication plays a pivotal role in transferring critical information in relation to aircraft safety and efficiency. The communication media used to convey the critical information between departments at an aircraft maintenance organisation have potential risk in misunderstanding of the information. In this study, technical and non-technical personnel from five different departments at an aircraft maintenance organisation were interviewed on the communication media they normally utilised to communicate six different work procedures that are closely related to aircraft safety and efficiency. This is to discover which communication media pose higher risk in misunderstanding critical information. The findings reveal that written communication pose higher risk of misinterpretation compared with verbal communication when conveying critical information between departments.
1984-06-01
index fiber has approximately 400 MHz/km. In the near future improvements in the material dispersion of glass may allow single mode bandwidths well above...attractive for K-band *(12 GI~z) TYRO, high definition TV channels, as well as the SBS (Satellite Business Systems) operation, in the near future.1...34Noise and Distortion Characteristics of Semi-Conductor Lasers in Optical Fiber Communication Systems", IEEE J. Quantum Electron., vol. QE-18, pp. 543-555
An Optical Fiber Communication System Based on Coherent Modulation. Part 1.
1985-06-01
the’ local oscillator signal. In the receiver the two signals are recombined optically using a single mode fiber coupler or a beam splitter , and the...Fig. 2. Design of practical systems may imply the use of non - ideal laser diodes. In a cooperation with British Telecom Research Labora- tories we...frequency stabilisation *the transmission fiber - *injection locking of semiconductor lasers *the coherent receiver Our next target is complete design
1985-09-01
BSTRACT This study uses a systems analysis approach to determine the communications technical control needs of the Fleet Marine Force as the transition...subsequent analysis and decision. In the acquisi- tion of military systems, it is typical to find these assumptions used to construct various measures of...relatively free from the typical underlying estimates used in cost and operational effective- ness analysis (COEA) type studies which are designed to compare
ERIC Educational Resources Information Center
Von Seggern, Marilyn; Jourdain, Janet M.
1996-01-01
A survey of the different technical communications and information-related activities of 305 engineers and scientists from 3 sites of the Philips Laboratory, an Air Force research and development laboratory, found that scientists have a closer affinity for libraries and traditional information sources than do engineers. Eight tables depict survey…
ERIC Educational Resources Information Center
Tillery, Denise
2001-01-01
Argues that the philosophical hermeneutics of Hans-Georg Gadamer provides a useful theoretical framework from which to discuss ethical issues in the technical communication classroom. Analyzes a previously published case study to demonstrate how hermeneutics can shed light on the ways that writers can be unconscious of ethical problems in their…
ERIC Educational Resources Information Center
Ford, Julie Dyke; Bracken, Jennifer L.; Wilson, Gregory D.
2009-01-01
This article addresses previous arguments that call for increased emphasis on research in technical communication programs. Focusing on the value of scholarly-based research at the undergraduate level, we present New Mexico Tech's thesis model as an example of helping students develop familiarity with research skills and methods. This two-semester…
(Re)Kindle: On the Value of Storytelling to Technical Communication
ERIC Educational Resources Information Center
Small, Nancy
2017-01-01
In an effort to expand the range of ways graduate programs prepare students to be scholars and practitioners in technical and professional communication, this article argues for a fresh direct reengagement with stories, storytelling, and narrative as valuable ways of studying and effectively producing the varied texts of the workplace. The…
ERIC Educational Resources Information Center
Dahm, Kevin; Newell, James
2001-01-01
Reports on a course at Rowan University, based on the economic design of a baseball stadium, that offers an introduction to multidisciplinary engineering design linked with formal training in technical communication. Addresses four pedagogical goals: (1) developing public speaking skills in a realistic, business setting; (2) giving students…
"Is This Ethical?" A Survey of Opinion on Principles and Practices of Document Design.
ERIC Educational Resources Information Center
Dragga, Sam
1996-01-01
Reprints a corrected version of an article originally published in the volume 43, number 1 issue of this journal. Presents results of a national survey of technical communicators and technical communication teachers assessing the ethics of seven document design cases involving manipulation of typography, illustrations, and photographs. Offers…
ERIC Educational Resources Information Center
Ross, Susan Mallon
1994-01-01
Describes the current practices in public environmental debate and reform movements as relevant to technical communicators. Reviews a case in which the Mohawk community clashed with the Environmental Protection Agency. Explores the clash of worldviews and shows how a feminist perspective might aid in such a conflict. (HB)
Helping Doctoral Students Establish Long-Term Identities as Technical Communication Scholars
ERIC Educational Resources Information Center
Grant-Davie, Keith; Matheson, Breeanne; Stephens, Eric James
2017-01-01
This article aims to help doctoral students in technical communication prepare themselves for the academic job market and for the subsequent process of earning tenure and promotion in increasingly demanding environments. The authors propose that students do four things: (a) learn to spot and articulate research problems; (b) find their…
ERIC Educational Resources Information Center
Williams, Miriam F.
2012-01-01
The author uses game theoretical models to identify technical communication breakdowns encountered during the notoriously confusing Texas Two-Step voting and caucusing process. Specifically, the author uses narrative theory and game theory to highlight areas where caucus participants needed instructions to better understand the rules of the game…
ERIC Educational Resources Information Center
Gochhayat, Jyotiranjan; Giri, Vijai N.; Suar, Damodar
2017-01-01
This study provides a new conceptualization of educational leadership with a multilevel and integrative approach. It examines the impact of multilevel leadership (MLL) on the effectiveness of technical educational institutes through the mediating effects of organizational communication, bases of power and organizational culture. Data were…
A Review of Technical Communication Programs Outside the United States.
ERIC Educational Resources Information Center
Alred, Gerald J.
2001-01-01
Examines technical communication programs outside the United States and comments on such features as their location in the university structure, links with public relations, the inclusion of internships or practicums, the balance of theory and practice, and typical course offerings. Lists a dozen major programs in seven countries. Concludes that…
A Friend in Your Neighborhood: Local Risk Communication in a Technical Writing Classroom
ERIC Educational Resources Information Center
Rhodes, Lynne
2009-01-01
When examined rhetorically, Savannah River Site Community Preparedness Information calendars from 1994, 2004, and 2008 represent living rhetorical practices aimed at changing the public mind. My technical communication classroom at USC Aiken is uniquely situated for us to examine documents constantly generated by the site's Public Affairs…
Using Isocrates to Teach Technical Communication and Civic Engagement
ERIC Educational Resources Information Center
Brizee, Allen
2015-01-01
Building on work by Dubinsky, Haskins, and Simmons and Grabill, this article explains how a technical communication instructor used Isocrates and informal usability testing to help guide a service-learning project involving the One Laptop Per Child XO-1 notebook. For the project, engineering students received feedback from peers and elementary…
Content Analysis as a Best Practice in Technical Communication Research
ERIC Educational Resources Information Center
Thayer, Alexander; Evans, Mary; McBride, Alicia; Queen, Matt; Spyridakis, Jan
2007-01-01
Content analysis is a powerful empirical method for analyzing text, a method that technical communicators can use on the job and in their research. Content analysis can expose hidden connections among concepts, reveal relationships among ideas that initially seem unconnected, and inform the decision-making processes associated with many technical…
ERIC Educational Resources Information Center
Maule, R. William
1993-01-01
Discussion of the role of new computer communications technologies in education focuses on modern networking systems, including fiber distributed data interface and Integrated Services Digital Network; strategies for implementing networked-based communication; and public online information resources for the classroom, including Bitnet, Internet,…
Teaching foreign languages to technical students by means of educational online technologies
NASA Astrophysics Data System (ADS)
Ivleva, Natalia V.; Fibikh, Ekaterina V.
2015-01-01
The article reveals new methods of effectiveness increase in teaching foreign languages to technical students using information and communication technologies and their practical implementation at the premises of the Foreign Languages Resource Center of Siberian State Aerospace University. Adoption of information and communication technologies to the educational process is based on students' independent language learning that encourages more productive development of language competences mastered by students and future specialists in a special area of technical knowledge as a whole.
NASA Technical Reports Server (NTRS)
Cudmore, Alan; Flanegan, Mark
1993-01-01
The NASA Small Explorer Data System (SEDS), a space flight data system developed to support the Small Explorer (SMEX) project, is addressed. The system was flown on the Solar Anomalous Magnetospheric Particle Explorer (SAMPEX) SMEX mission, and with reconfiguration for different requirements will fly on the X-ray Timing Explorer (XTE) and the Tropical Rainfall Measuring Mission (TRMM). SEDS is also foreseen for the Hubble repair mission. Its name was changed to Spacecraft Data System (SDS) in view of expansions. Objectives, SDS hardware, and software are described. Each SDS box contains two computers, data storage memory, uplink (command) reception circuitry, downlink (telemetry) encoding circuitry, Instrument Telemetry Controller (ITC), and spacecraft timing circuitry. The SDS communicates with other subsystems over the MIL-STD-1773 data bus. The SDS software uses a real time Operating System (OS) and the C language. The OS layer, communications and scheduling layer, application task layer, and diagnostic software, are described. Decisions on the use of advanced technologies, such as ASIC's (Application Specific Integrated Circuits) and fiber optics, led to technical improvements, such as lower power and weight, without increasing the risk associated with the data system. The result was a successful SAMPEX development, integration and test, and mission using SEDS, and the upgrading of that system to SDS for TRMM and XTE.
Fiber-optic sensor demonstrator (FSD) for the monitoring of spacecraft subsystems on ESA's PROBA-2
NASA Astrophysics Data System (ADS)
Kruzelecky, Roman V.; Zou, Jing; Mohammed, Najeeb; Haddad, Emile; Jamroz, Wes; Ricci, Francesco; Lamorie, Joshua; Edwards, Eric; McKenzie, Iain; Vuilleumier, Pierrik
2017-11-01
MPB Communications (MPBC) is developing solutions to the monitoring requirements of spacecraft based on its fiber-laser and Fiber Bragg Grating expertise. This is cumulating in the Fiber Sensor Demonstrator for ESA's Proba-2 that is scheduled for launch in 2007. The advantages of the MPBC approach include a central interrogation system that can be used to control a variety of different fiber-optic sensors including temperature, pressure, actuator status, and propellant leakage. This paper reviews the design and ground qualification of the FSD system in preparation for integration with Proba-2. The FSD will provide monitoring for various Proba-2 subsystems, including a hybrid propulsion system. Some of the challenges associated with using fiber-optics in space are discussed.
Embedded 100 Gbps Photonic Components
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuznia, Charlie
This innovation to fiber optic component technology increases the performance, reduces the size and reduces the power consumption of optical communications within dense network systems, such as advanced distributed computing systems and data centers. VCSEL technology is enabling short-reach (< 100 m) and >100 Gbps optical interconnections over multi-mode fiber in commercial applications.
NASA Technical Reports Server (NTRS)
Valley, G. C.; Wright, M.
2001-01-01
Simulations of 1-50 kHz repetition rate, pulsed Yb-fiber amplifiers show peak powers to 10 kW with half-widths < 30 ns, consistent with commercial amplifier performance. This device is a potential source for deep space-communication.
NASA Astrophysics Data System (ADS)
Wang, Yubao; Zhu, Zhaohui; Wang, Lu; Bai, Jian
2016-05-01
A novel GPON-oriented sensing data digitalization system is proposed to achieve remote monitoring of fiber grating sensing networks utilizing existing optical communication networks in some harsh environments. In which, Quick digitalization of sensing information obtained from the reflected lightwaves by fiber Bragg grating (FBG) sensor is realized, and a novel frame format of sensor signal is designed to suit for public transport so as to facilitate sensor monitoring center to receive and analyze the sensor data. The delay effect, identification method of the sensor data, and various interference factors which influence the sensor data to be correctly received are analyzed. The system simulation is carried out with OptiSystem/Matlab co-simulation approach. The theoretical analysis and simulation results verify the feasibility of the integration of the sensor network and communication network.
NASA Astrophysics Data System (ADS)
Bogachkov, I. V.; Lutchenko, S. S.
2018-05-01
The article deals with the method for the assessment of the fiber optic communication lines (FOCL) reliability taking into account the effect of the optical fiber tension, the temperature influence and the built-in diagnostic equipment errors of the first kind. The reliability is assessed in terms of the availability factor using the theory of Markov chains and probabilistic mathematical modeling. To obtain a mathematical model, the following steps are performed: the FOCL state is defined and validated; the state graph and system transitions are described; the system transition of states that occur at a certain point is specified; the real and the observed time of system presence in the considered states are identified. According to the permissible value of the availability factor, it is possible to determine the limiting frequency of FOCL maintenance.
Deri, Robert J.; DeGroot, Anthony J.; Haigh, Ronald E.
2002-01-01
As the performance of individual elements within parallel processing systems increases, increased communication capability between distributed processor and memory elements is required. There is great interest in using fiber optics to improve interconnect communication beyond that attainable using electronic technology. Several groups have considered WDM, star-coupled optical interconnects. The invention uses a fiber optic transceiver to provide low latency, high bandwidth channels for such interconnects using a robust multimode fiber technology. Instruction-level simulation is used to quantify the bandwidth, latency, and concurrency required for such interconnects to scale to 256 nodes, each operating at 1 GFLOPS performance. Performance scales have been shown to .apprxeq.100 GFLOPS for scientific application kernels using a small number of wavelengths (8 to 32), only one wavelength received per node, and achievable optoelectronic bandwidth and latency.
NASA Technical Reports Server (NTRS)
Wang, F. F. Y.
1974-01-01
The feasibility, and technical and economic desirability was studied of space processing of glass preforms for optical fiber transmission applications. The results indicate that space processing can produce glass preforms of equal quality at lower cost than earth bound production, and can produce diameter modulation in the glass preform which promotes mode coupling and lowers the dispersion. The glass composition can be modified through the evaporative and diffusion processes, and graded refractive index profiles can be produced. A brief summary of the state of the art in optical fiber transmission is included.
Overview of technical trend of optical fiber/cable and research and development strategy of Samsung
NASA Astrophysics Data System (ADS)
Kim, Jin H.
2005-01-01
Fiber-to-the-Premise (FTTP), a keyword in the current fiber and cable industry, leads us variegated directions of the research and development activities. In fact, this momentum of industry seems to be weak yet, since the bandwidth demand by market is still unbalanced to the capacity in the several market segments. However, the recent gradual recovery in metro and access network indicates a positive sign for FTTP deployment projects. It is the very preferable for us to optimize R&D strategy applicable to the current market trend of sequential investment.
Doing Projects in a Foreign Language — Communications Management, Issues and Strategies
NASA Astrophysics Data System (ADS)
Xian, Deling
The Qinghai Salt Lake Industry Co. Ltd. (QSLIC) smelter project involves a Chinese state-owned client, a Canadian engineering company, their American technology partner, several Chinese design institutes and international vendors. Proper technical communication plays an important role during the development of a project in a foreign language and across cultures. Using the QSLIC project as an example, this paper presents the role of Communications Manager and personal qualifications required, as well as technical communications management, issues and strategies, lessons learnt while doing smelter projects in China and Chinese business culture and etiquette.
1980-12-01
now apply similar methods to KRS-5, TlBr , etc. to obtain better fiber material. 11 * hi LI * I. * ec - ~-,-. - * 1~-, * . SECTION 2 TECHNICAL PROGRESS...TOTAL FRESNEL 3 3 LOSS 1.45 dB TlBr I x 10 (0.43) 1 x 10 (0.4 ) 0.2 KCI 8 X 10 - 5 (0.(35) . x 10- 2 (4.2) 0I S.0.5 1.0 15S KBr I x 10 - (0.0004
Holographically Encoded Volume Phase Masks
2015-07-13
Lu et al., “Coherent beam combination of fiber laser arrays via multiplexed volume Bragg gratings,” in Conf. on Lasers and Electro- Optics: Science...combining of fiber lasers using multiplexed volume Bragg gratings,” in Conf. on Lasers and Electro- Optics: Science and Innovations, OSA Technical Digest...satisfying the Bragg condition of the hologram. Moreover, this approach enables the capability to encode and multiplex several phase masks into a single
Fracture of Fiber-Reinforced Beams due to Impact Loading
1975-03-01
high rates of tensile loading were made by Armenakas and Sciammarella [5, 6]. They found that the main contribution to the failure of the...2394, June 1974. Armenakas, A. E., and Sciammarella , C. A., "Experimental In- vestigation of the Failure Mechanisms of Fiber Reinforced Composites...Subjected to Uniaxial Tension," Technical Report AFML-TR-71-179, Air Force Materials Laboratory, August 1971. Armenakas, A. E., and Sciammarella , C. A
A Laboratory Manual for Stepwise Cerebral White Matter Fiber Dissection.
Koutsarnakis, Christos; Liakos, Faidon; Kalyvas, Aristotelis V; Sakas, Damianos E; Stranjalis, George
2015-08-01
White matter fiber dissection is an important method in acquiring a thorough neuroanatomic knowledge for surgical practice. Previous studies have definitely improved our understanding of intrinsic brain anatomy and emphasized on the significance of this technique in modern neurosurgery. However, current literature lacks a complete and concentrated laboratory guide about the entire dissection procedure. Hence, our primary objective is to introduce a detailed laboratory manual for cerebral white matter dissection by highlighting consecutive dissection steps, and to stress important technical comments facilitating this complex procedure. Twenty adult, formalin-fixed cerebral hemispheres were included in the study. Ten specimens were dissected in the lateromedial and 10 in the mediolateral direction, respectively, using the fiber dissection technique and the microscope. Eleven and 8 consecutive and distinctive dissection steps are recommended for the lateromedial and mediolateral dissection procedures, respectively. Photographs highlighting various anatomic landmarks accompany every step. Technical recommendations, facilitating the dissection process, are also indicated. The fiber dissection technique, although complex and time consuming, offers a three-dimensional knowledge of intrinsic brain anatomy and architecture, thus improving both the quality of microneurosurgery and the patient's standard of care. The present anatomic study provides a thorough dissection manual to those who study brain anatomy using this technique. Copyright © 2015 Elsevier Inc. All rights reserved.
Technical editing and the effective communication of scientific results
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pieper, G.W.; Picologlou, S.M.
1996-05-01
Communication of scientific results--whether for professional journals, poster sessions, oral presentations, or the popular press--is an essential part of any scientific investigation. The technical editor plays an important rolein ensuring that scientists express their results correctly and effectively. Technical editing comprises far more than simple proofreading. The editor`s tasks may range from restructuring whole parpagrphs and suggesting improved graphical aids to writing abstracts and preparing first drafts of proposals. The technical editor works closely with scientists to present complex ideas to differentaudiences, including fellow scentists, funding agencies, and the general public. New computer technologyhas also involved the technical editor notmore » only with on-line editing but also with preparing CD ROMs and World Wide Web pages.« less
Light Emitting Diodes for Fiber Optic Communications.
1981-03-31
asC.3~~ in.(c)- above and do- (1) pcait by volu.3 of dicst.iLle =zto.- Pazo 10 .61Edd, tcxcopt colvonts used cha-l bo: * ( a ) Methyl. alcohbl I7or 04...AD £101 480 LASER DIODE LABS INC NEW BRUNSWICK NJ / 1 / L I GT EMITTING DIODES FOR FIBER OPTIC COWMICATIONS.Cul AR, at A GENNARO DAARO-76-C-813 NA 1...PRArrcmA. P . 1"UNISPE-D TO DDC CONTAINE A II&~-’llryBE v., R OF :AO , MflG DO 9W CORADCOM U S ARMY COMMUNICATIONS RESEARCH 9 DEVELOPMENT COMMAND
NASA Astrophysics Data System (ADS)
Zou, Ding; Djordjevic, Ivan B.
2016-02-01
Forward error correction (FEC) is as one of the key technologies enabling the next-generation high-speed fiber optical communications. In this paper, we propose a rate-adaptive scheme using a class of generalized low-density parity-check (GLDPC) codes with a Hamming code as local code. We show that with the proposed unified GLDPC decoder architecture, a variable net coding gains (NCGs) can be achieved with no error floor at BER down to 10-15, making it a viable solution in the next-generation high-speed fiber optical communications.
PMD compensation in fiber-optic communication systems with direct detection using LDPC-coded OFDM.
Djordjevic, Ivan B
2007-04-02
The possibility of polarization-mode dispersion (PMD) compensation in fiber-optic communication systems with direct detection using a simple channel estimation technique and low-density parity-check (LDPC)-coded orthogonal frequency division multiplexing (OFDM) is demonstrated. It is shown that even for differential group delay (DGD) of 4/BW (BW is the OFDM signal bandwidth), the degradation due to the first-order PMD can be completely compensated for. Two classes of LDPC codes designed based on two different combinatorial objects (difference systems and product of combinatorial designs) suitable for use in PMD compensation are introduced.