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1

Animal Communication  

NSDL National Science Digital Library

The focus of this Science NetLinks lesson is threefold. First, to expose students to the fact that all species have a capacity for communication. Second, to enlighten students to the fact that communication abilities range from very simple to extremely complex, depending upon the species. Third, to realize that communication is influenced by a species' genetic makeup, its environment, and the numerous ways by which animals and humans respond to and adapt to their surroundings.

Science Netlinks

2003-09-09

2

Animal and Human Communication.  

ERIC Educational Resources Information Center

Several misconceptions regarding the status of human communication systems relative to the systems of other animals are discussed in this paper. Arguments are offered supporting the expansion of the communication discipline to include the study of the communication systems of other species. The "communicative continuity" view which ranks man at…

Rummel, Lynda

3

Quantitative tools for comparing animal communication systems: information theory applied to bottlenose dolphin whistle repertoires  

Microsoft Academic Search

Comparative analysis of nonhuman animal communication systems and their complexity, particularly in comparison to human language, has been generally hampered by both a lack of sufficiently extensive data sets and appropriate analytic tools. Information theory measures provide an important quantitative tool for examining and comparing communication systems across species. In this paper we use the original application of information theory,

BRENDA McCOWAN; SEAN F. HANSER; LAURANCE R. DOYLE

1999-01-01

4

Information Theory Applied to Animal Communication Systems and Its Possible Application to SETI  

Microsoft Academic Search

Information theory, as first introduced by Claude Shannon (Shannon &Weaver 1949) quantitatively evaluates the organizational complexity of communication systems. At the same time George Zipf was examining linguistic structure in a way that was mathematically similar to the components of the Shannon first-order entropy (Zipf 1949). Both Shannon's and Zipf's mathematical procedures have been applied to animal communication and recently

Sean F. Hanser; Laurance R. Doyle; Brenda McCowan; Jon M. Jenkins

2004-01-01

5

Exms: an animated and avatar-based messaging system for expressive peer communication  

Microsoft Academic Search

While many synchronous computer-mediated communication systems have failed to encourage users to make use of the expressive capabilities of their avatars, asynchronous systems may hold better chance. This paper reports on the design and user study of a message system that allows users to concatenate and annotate avatar animations and send them to peers. During three weeks, a group of

Per Persson

2003-01-01

6

The Animal Communication Project  

NSDL National Science Digital Library

This streamlined website is very accessible to the lay reader, while it also has enough references to scientific studies to appeal to teachers, researchers, and students of animal communication and biology in general. The site contains the full-text of the (now out-of-print) book, The Language of Animals, in addition to "Research News" and some multimedia features. The type of animal communication this website refers to is not that between animals and humans, but among animals. Visitors with pet dogs or cats might enjoy the section on "Cats and Dogs" that explains how lions communicate, and why the domesticated dog barks, but other members of the dog family, such as wolves and coyotes, do not.

7

Assessing and communicating animal  

E-print Network

framework of risk communication. The initial focus will be on Lyme disease (also known as Lyme borreliosis), an infectious disease caused by the bacterium Borrelia burgdorferi s.l. Lyme disease is found in a number.quine@forestresearch.gsi.gov.uk Authoritative health protection advice on Lyme disease and other zoonotic diseases can be found at: www

8

Animal Communications Through Seismic Vibrations  

SciTech Connect

Substrate vibration has been important to animals as a channel of communication for millions of years, but our literature on vibration in this context of biologically relevant information is only decades old. The jaw mechanism of the earliest land vertebrates allowed them to perceive substrate vibrations as their heads lay on the ground long before airborne sounds could be heard. Although the exact mechanism of vibration production and the precise nature of the wave produced are not always understood, recent development of affordable instrumentation to detect and measure vibrations has allowed researchers to answer increasingly sophisticated questions about how animals send and receive vibration signals. We now know that vibration provides information used in predator defense, prey detection, recruitment to food, mate choice, intrasexual competition, and maternal/brood social interactions in a variety of insect orders, spiders, crabs, scorpions, chameleons, frogs, golden moles, mole rats, kangaroos rats, wallabies, elephants and bison.

Hill, Peggy (University of Tulsa) [University of Tulsa

2001-05-02

9

All about Animal Behavior & Communication. Animal Life for Children. [Videotape].  

ERIC Educational Resources Information Center

Why do animals do what they do? What is the difference between instinct and learned behavior? How do animals communicate? These questions are answered as children examine animal behaviors that help them find food, protect themselves, and care for their young. This videotape correlates to the following National Science Education Standards for Life…

2000

10

The use of network analysis to study complex animal communication systems: a study on nightingale song.  

PubMed

The singing of song birds can form complex signal systems comprised of numerous subunits sung with distinct combinatorial properties that have been described as syntax-like. This complexity has inspired inquiries into similarities of bird song to human language; but the quantitative analysis and description of song sequences is a challenging task. In this study, we analysed song sequences of common nightingales (Luscinia megarhynchos) by means of a network analysis. We translated long nocturnal song sequences into networks of song types with song transitions as connectors. As network measures, we calculated shortest path length and transitivity and identified the 'small-world' character of nightingale song networks. Besides comparing network measures with conventional measures of song complexity, we also found a correlation between network measures and age of birds. Furthermore, we determined the numbers of in-coming and out-going edges of each song type, characterizing transition patterns. These transition patterns were shared across males for certain song types. Playbacks with different transition patterns provided first evidence that these patterns are responded to differently and thus play a role in singing interactions. We discuss potential functions of the network properties of song sequences in the framework of vocal leadership. Network approaches provide biologically meaningful parameters to describe the song structure of species with extremely large repertoires and complex rules of song retrieval. PMID:24807258

Weiss, Michael; Hultsch, Henrike; Adam, Iris; Scharff, Constance; Kipper, Silke

2014-06-22

11

Information theory, animal communication, and the search for extraterrestrial intelligence  

Microsoft Academic Search

We present ongoing research in the application of information theory to animal communication systems with the goal of developing additional detectors and estimators for possible extraterrestrial intelligent signals. Regardless of the species, for intelligence (i.e., complex knowledge) to be transmitted certain rules of information theory must still be obeyed. We demonstrate some preliminary results of applying information theory to socially

Laurance R. Doyle; Brenda McCowan; Simon Johnston; Sean F. Hanser

2011-01-01

12

New Waves in Marine Science Symposium: Marine Animal Communication.  

ERIC Educational Resources Information Center

Presented are the abstracts from three research projects on marine social systems which were a part of a marine science symposium. Five sets of activities on marine animal communication are included, one each for grades K-2, 3-5, 6-8 and 9-12, and informal education. (CW)

Allen, Betty, Comp.

1989-01-01

13

Video animation system  

SciTech Connect

A video animation system is being used at Sandia Laboratories in Albuquerque to record computer generated images directly onto 3/4'' videocassettes. The system serves as a quick turn around process for previewing sequences prior to sending them to a Dicomed film recorder. It is also used when videocassette is appropriate for final output. The video animation system in place at Sandia is described. The system consists of a medium resolution graphics display system, a 3/4'' professional quality videocassette recorder, and a controller that allows single frame recording of computer generated images to be performed under program control. Examples of output produced using this system are presented which will include animated sequences of scientific data produced by DISSPLA programs.

Mareda, J.

1985-01-01

14

Communication Systems Chair of Communication Systems  

E-print Network

of GSM overview ­ GSM interfaces ­ GSM network components Mobile switching center,visitor location;3 | 36 Communication Systems GSM interfaces and components #12;4 | 36 Communication Systems GSM (HLR) #12;5 | 36 Communication Systems GSM interfaces and components The several MSC

Schindelhauer, Christian

15

Information theory, animal communication, and the search for extraterrestrial intelligence  

NASA Astrophysics Data System (ADS)

We present ongoing research in the application of information theory to animal communication systems with the goal of developing additional detectors and estimators for possible extraterrestrial intelligent signals. Regardless of the species, for intelligence (i.e., complex knowledge) to be transmitted certain rules of information theory must still be obeyed. We demonstrate some preliminary results of applying information theory to socially complex marine mammal species (bottlenose dolphins and humpback whales) as well as arboreal squirrel monkeys, because they almost exclusively rely on vocal signals for their communications, producing signals which can be readily characterized by signal analysis. Metrics such as Zipf's Law and higher-order information-entropic structure are emerging as indicators of the communicative complexity characteristic of an "intelligent message" content within these animals' signals, perhaps not surprising given these species' social complexity. In addition to human languages, for comparison we also apply these metrics to pulsar signals—perhaps (arguably) the most "organized" of stellar systems—as an example of astrophysical systems that would have to be distinguished from an extraterrestrial intelligence message by such information theoretic filters. We also look at a message transmitted from Earth (Arecibo Observatory) that contains a lot of meaning but little information in the mathematical sense we define it here. We conclude that the study of non-human communication systems on our own planet can make a valuable contribution to the detection of extraterrestrial intelligence by providing quantitative general measures of communicative complexity. Studying the complex communication systems of other intelligent species on our own planet may also be one of the best ways to deprovincialize our thinking about extraterrestrial communication systems in general.

Doyle, Laurance R.; McCowan, Brenda; Johnston, Simon; Hanser, Sean F.

2011-02-01

16

A simple frequency-scaling rule for animal communication  

Microsoft Academic Search

Different animals use widely different frequencies for sound communication, and it is reasonable to assume that evolution has adapted these frequencies to give greatest conspecific communication distance for a given vocal effort. Acoustic analysis shows that the optimal communication frequency is inversely proportional to about the 0.4 power of the animal's body mass. Comparison with observational data indicates that this

Neville H. Fletcher

2004-01-01

17

The Communicative Functions of Animation in User Interfaces  

E-print Network

The Communicative Functions of Animation in User Interfaces David Novick The University of Texas@gmail.com ABSTRACT To develop a model that relates the purpose of the communication to the nature of the animation, we surveyed existing user interfaces that use animation, analyzed these uses with respect to type

Novick, David G.

18

Secure video communications system  

DOEpatents

A secure video communications system having at least one command network formed by a combination of subsystems. The combination of subsystems to include a video subsystem, an audio subsystem, a communications subsystem, and a control subsystem. The video communications system to be window driven and mouse operated, and having the ability to allow for secure point-to-point real-time teleconferencing.

Smith, Robert L. (Idaho Falls, ID)

1991-01-01

19

A simple frequency-scaling rule for animal communication  

NASA Astrophysics Data System (ADS)

Different animals use widely different frequencies for sound communication, and it is reasonable to assume that evolution has adapted these frequencies to give greatest conspecific communication distance for a given vocal effort. Acoustic analysis shows that the optimal communication frequency is inversely proportional to about the 0.4 power of the animal's body mass. Comparison with observational data indicates that this prediction is well supported in practice. For animals of a given class, for example mammals, the maximum communication distance varies about as the 0.6 power of the animal's mass. There is, however, a wide spread of observed results because of the different emphasis placed upon vocal effort in the evolution of different animal species.

Fletcher, Neville H.

2004-05-01

20

The IRIDIUM communications system  

Microsoft Academic Search

A description is given of the IRIDIUM communication system, so-called because the system design originally consisted of 77 networked satellites, and the element iridium has the atomic number 77. The goal is to make instant global communications a reality. The system design now consists of 60 satellites, a system control facility, gateways, and subscriber units. Each of these components is

R. J. Leopold; A. Miller

1993-01-01

21

Information Theory as a Comparative Measure of Animal Communication  

Microsoft Academic Search

Information theoretic measurements of communication repertoires quantify the organizational complexity and potential communication capacity of signaling systems with unknown structure and function. The most important advantage of measuring signaling systems quantitatively is that it allows one to examine qualitatively different communication systems on a truly comparative scale. We will illustrate the utility of this information theoretic approach by outlining various

Sean Hanser; Brenda McCowan; Laurance Doyle

2000-01-01

22

Binary and Communication Systems  

NSDL National Science Digital Library

Students are introduced to the concept of binary coding as a language and its practical applications in digital and communication systems.This project gives students a deeper appreciation for communication systems and an understanding of how binary symbols are used to transmit information.

2012-06-21

23

Advanced communications satellite systems  

NASA Technical Reports Server (NTRS)

There is a rapidly growing demand for satellite circuits, particularly for domestic service within the U.S. NASA's current program is aimed at developing the high risk, advanced satellite communications technologies required to significantly increase the capacity of future satellite communications systems. Attention is given to aspects of traffic distribution and service scenario, problems related to effects of rain attenuation, details regarding system configuration, a 30/20 GHz technology development approach, an experimental flight system, the communications payload for the experimental flight system, a typical experiment flight system coverage, and a typical three axis stabilized flight spacecraft.

Sivo, J. N.

1983-01-01

24

Animal Communication and Its Cognitive Indications.  

ERIC Educational Resources Information Center

Various examples of communication in species ranging from bumble bees to dolphins are examined in this paper. Focus is directed to indications of the cognitive ability of each species. The signals of cognition include evidence of: adaptability to a new situation; long term memory; and the property of displacement. Most of the sources reviewed…

McLean, Laura L.

25

Communication system modeling  

NASA Technical Reports Server (NTRS)

This report presents the results of work on communications systems modeling and covers three different areas of modeling. The first of these deals with the modeling of signals in communication systems in the frequency domain and the calculation of spectra for various modulations. These techniques are applied in determining the frequency spectra produced by a unified carrier system, the down-link portion of the Command and Communications System (CCS). The second modeling area covers the modeling of portions of a communication system on a block basis. A detailed analysis and modeling effort based on control theory is presented along with its application to modeling of the automatic frequency control system of an FM transmitter. A third topic discussed is a method for approximate modeling of stiff systems using state variable techniques.

Holland, L. D.; Walsh, J. R., Jr.; Wetherington, R. D.

1971-01-01

26

AMPA experimental communications systems  

NASA Technical Reports Server (NTRS)

The program was conducted to demonstrate the satellite communication advantages of Adaptive Phased Array Technology. A laboratory based experiment was designed and implemented to demonstrate a low earth orbit satellite communications system. Using a 32 element, L-band phased array augmented with 4 sets of weights (2 for reception and 2 for transmission) a high speed digital processing system and operating against multiple user terminals and interferers, the AMPA system demonstrated: communications with austere user terminals, frequency reuse, communications in the face of interference, and geolocation. The program and experiment objectives are described, the system hardware and software/firmware are defined, and the test performed and the resultant test data are presented.

Beckerman, D.; Fass, S.; Keon, T.; Sielman, P.

1982-01-01

27

Risk communication related to animal products derived from biotechnology.  

PubMed

Previous chapters of this review have dealt with the key considerations related to the application of biotechnology in veterinary science and animal production. This article explores the theory and practice of risk communication and sets out the basic principles for good risk communication when dealing with new technologies, uncertainty, and cautious and sceptical consumers. After failure to communicate with consumers and stakeholders about the risk to human health from bovine spongiform encephalopathy (BSE) in the 1990s, Government Agencies in the United Kingdom have made significant improvements in risk communication. The official inquiry that followed the BSE crisis concluded that a policy of openness was the correct approach, and this article emphasises the importance of consultation, consistency and transparency. There are, however, many different factors that affect public perception of risk (religious, political, social, cultural, etc.) and developing effective risk communication strategies must take all of these complex issues into consideration. PMID:16110884

McCrea, D

2005-04-01

28

Animal breeding systems  

Microsoft Academic Search

The study of breeding systems explores relationships between mating behaviour and parental care. Recent findings have shown that in many birds, fishes, anurans, and insects, females play a more active role than previously thought, by engaging in mate choice, mating with more than one male, and selecting genetic partners separately from social partners. Theoretical advances have improved our understanding of

John D. Reynolds

1996-01-01

29

Alert signals enhance animal communication in "noisy" environments  

E-print Network

Alert signals enhance animal communication in "noisy" environments Terry J. Orda,b,1 and Judy A with conspicuous "alerting" components to attract the attention of receivers, before delivery of the information that alerts might exist in a variety of taxa. By using a combination of behavioral observations

Ord, Terry

30

Video animation system operators manual  

SciTech Connect

This document describes the components necessary to put together a video animation system. It is primarily intended for use at Sandia National Laboratories as it describes the components used in systems at Sandia. The main document covers the operation of the equipment in some detail and is intended for either the system maintainer or an advanced user. There is an appendix for each of the three systems in use by the Engineering Sciences Directorate which contain instructions for the general user.

Mareda, J.F.

1992-09-01

31

DYMAC communications system  

NASA Astrophysics Data System (ADS)

The DYMAC Communications System is part of a nuclear safeguard system called DYMAC - short for DYnamic Materials ACcountability -that gathers accountability information at the Los Alamos Scientific Laboratory (LASL) Plutonium Processing Facility. The communications system handles transmissions between data entry terminals and nondestructive assay instruments located in the facility, and a computer located in a adjacent building. The components that make up the communication network are described including how they operate, and detailed information about all of the connections. Circuit diagrams for all the LASL modifications and LASL fabricated equipment are provided. In addition, a series of procedures are described for tracing cables, reconfiguring various parts of the system, testing data transmissions, and troubleshooting malfunctions.

Lindsey, K. A.

1980-01-01

32

INCO shuttle communication system  

NASA Technical Reports Server (NTRS)

In a previous work we have defined a general architectural model for autonomous systems, which can be mapped easily to describe the functions of any automated system (SDAG-86-01). In this note, we use the model to describe the Shuttle communication system. First we briefly review the architecture, then we present the environment of our application, and finally we detail the specific function for each functional block of the architecture for that environment.

Dikshit, Piyush; Guimaraes, Katia; Ramamurthy, Maya; Agrawala, Ashok K.; Larsen, Ronald L.

1989-01-01

33

A system for algorithm animation  

Microsoft Academic Search

A software environment is described which provides facilities at a variety of levels for “animating” algorithms: exposing properties of programs by displaying multiple dynamic views of the program and associated data structures. The system is operational on a network of graphics-based, personal workstations and has been used successfully in several applications for teaching and research in computer science and mathematics.

Marc H. Brown; Robert Seclgewick

1984-01-01

34

Communication Systems. Laboratory Activities.  

ERIC Educational Resources Information Center

This communication systems guide provides teachers with learning activities for secondary students. Introductory materials include an instructional planning outline and worksheet, an outline of essential elements, a list of objectives, a course description, and a content outline. The guide contains 32 modules on the following topics: story…

Sutherland, Barbara, Ed.

35

Real-time speech animation system  

E-print Network

We optimize the synthesis procedure of a videorealistic speech animation system [7] to achieve real-time speech animation synthesis. A synthesis rate must be high enough for real-time video streaming for speech animation ...

Fu, Jieyun

2011-01-01

36

Wireless Headset Communication System  

NASA Technical Reports Server (NTRS)

System combines features of pagers, walkie-talkies, and cordless telephones. Wireless headset communication system uses digital modulation on spread spectrum to avoid interference among units. Consists of base station, 4 radio/antenna modules, and as many as 16 remote units with headsets. Base station serves as network controller, audio-mixing network, and interface to such outside services as computers, telephone networks, and other base stations. Developed for use at Kennedy Space Center, system also useful in industrial maintenance, emergency operations, construction, and airport operations. Also, digital capabilities exploited; by adding bar-code readers for use in taking inventories.

Lau, Wilfred K.; Swanson, Richard; Christensen, Kurt K.

1995-01-01

37

Degree project in Communication Systems  

E-print Network

. Maguire Jr. School of Information and Communication Technology (ICT) KTH Royal Institute of TechnologyDegree project in Communication Systems Second level, 30.0 HEC Stockholm, Sweden R U S L A N M U K and Communication Technology #12;A scalable database for a remote patient monitoring system Ruslan Mukhammadov

Maguire Jr., Gerald Q.

38

Insat communication system  

NASA Astrophysics Data System (ADS)

The Insat-1 domestic satellite system has been planned as a cost-effective multipurpose system for providing long distance telecommunications, direct TV broadcasting, to rural areas, and meteorological services, and is due to be operational in early 1982. The system will consist of two body-stabilized satellites in geostationary orbit and 34 earth stations, operating in the 6/4 GHz band for telecommunications. This paper describes the salient features of the Insat system. The domestic telecommunication requirements are presented, and the main characteristics of the spacecraft communication subsystem and earth stations are given. The transmission parameters of the Insat carriers are discussed, and the features of network operation and the control center are examined.

Nayak, U. V.; Matapurkar, K. G.

39

INTRODUCTION As one of the most common forms of communication in animals  

E-print Network

3513 INTRODUCTION As one of the most common forms of communication in animals (Hill, 2008 substrates vary in their transmission properties among species and individuals (Henry and Wells, 2004 techniques. SUMMARY Substrate-borne vibrational communication is a common form of communication in animals

RodrĂ­guez, Rafael Lucas

40

The Picture Exchange Communication System  

Microsoft Academic Search

A variety of strategies have been used to help children with autism acquire functional communication skills. The Picture Exchange Communication System (PECS) is a unique communication training program that was developed as a means of circumventing some shortcomings associatd with these strategies. A description of the steps within PECS is provided. Long-term group data have indicated that a large proportion

Andrew S. Bondy; Lori A. Frost

1994-01-01

41

AAML Based Avatar Animation with Personalized Expression for Online Chatting System  

Microsoft Academic Search

This paper presents an online chatting system with automatic expression animation and animated avatar. The system is constructed\\u000a upon an XML based language AAML (Affective Animation Markup Language), which describes hierarchically affective content for\\u000a online communication. Once the user types a chatting sentence, the AAML produces a piece of personalized facial animation.\\u000a The animation would be sent to the remote

Junfa Liu; Yiqiang Chen; Xingyu Gao; Jinjing Xie; Wen Gao

2008-01-01

42

Security for Industrial Communication Systems  

Microsoft Academic Search

Modern industrial communication networks are increasingly based on open protocols and platforms that are also used in the office IT and Internet environment. This reuse facilitates development and deployment of highly connected systems, but also makes the communication system vulnerable to electronic attacks. This paper gives an overview of IT security issues in industrial automation systems which are based on

DACFEY DZUNG; MARTIN NAEDELE; THOMAS P. VON HOFF; MARIO CREVATIN

2005-01-01

43

General data base driven graphic animation system  

SciTech Connect

Most attempts at the graphic animation of data involve rather large and expensive development of problem-specific systems. This paper discusses a general graphics animation system designed to be a tool for the development of a wide variety of animated simulations. By incorporating device-independent graphics procedures and using relational database storage of graphics and control information, considerable flexibility in the design and development of animated displays is achieved. 6 refs., 4 figs.

Not Available

1986-01-01

44

Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture  

DOEpatents

Communications device identification methods, communications methods, wireless communications readers, wireless communications systems, and articles of manufacture are described. In one aspect, a communications device identification method includes providing identification information regarding a group of wireless identification devices within a wireless communications range of a reader, using the provided identification information, selecting one of a plurality of different search procedures for identifying unidentified ones of the wireless identification devices within the wireless communications range, and identifying at least some of the unidentified ones of the wireless identification devices using the selected one of the search procedures.

Steele, Kerry D [Kennewick, WA; Anderson, Gordon A [Benton City, WA; Gilbert, Ronald W [Morgan Hill, CA

2011-02-01

45

Degree project in Communication Systems  

E-print Network

S I D D I Q I Smart Card Packaging Process Control System KTH Information and Communication Technology #12;Smart Card Packaging Process Control System Saad Ahmed Siddiqi August 1, 2012 Masters Thesis Högskolan) KTH Royal Institute of Technology School of Information and Communication Technology Stockholm

Maguire Jr., Gerald Q.

46

Communications in Electronic Textile Systems  

Microsoft Academic Search

Electronic textiles (e-textiles) are emerging as a novel method for constructing electronic systems in wearable and large area applications. This new type of processing system merges textile and electronic technologies. This paper studies the communication requirements between the computing and sensing elements of an e-textile. This communication is studied through the construction of a prototype as well as through modeling

Zahi Nakad; Mark T. Jones; Thomas Martin

2003-01-01

47

Constraint-based animation: temporal constraints in the Animus systems  

SciTech Connect

Algorithm animation has a growing role in computer-aided algorithm design documentation and debugging, since interactive graphics is a richer channel than text for communication. Most animation is currently done laboriously by hand, and it often has the character of canned demonstrations with restricted user interaction. Animus is a system that allows easy construction of an animation with minimal concern for lower-level graphics programming. Constraints are used to describe the appearance and structure of a picture as well as how those pictures evolve in time. The implementation and support of temporal constraints is a substantive extension to previous constraint languages which had only allowed specification of static state. Use of the Animus system is demonstrated in the creation of animations of dynamic mechanical and electrical-circuit simulations, sorting algorithms, problems in operating systems, and geometric curve-drawing algorithms.

Duisberg, R.A.

1986-01-01

48

INMARSAT's personal communicator system  

NASA Astrophysics Data System (ADS)

Inmarsat has been providing near global mobile satellite communications since 1982 and Inmarsat terminals are currently being used in more than 130 countries. The terminals have been reduced in size and cost over the years and new technology has enabled the recent introduction of briefcase sized personal telephony terminals (Inmarsat-M). This trend continues and we are likely to see Inmarsat handheld terminals by the end of the decade. These terminals are called Inmarsat-P and this paper focuses on the various elements required to support a high quality service to handheld terminals. The main system elements are: the handheld terminals; the space segment with the associated orbits; and the gateways to terrestrial networks. It is both likely and desirable that personal handheld satellite communications will be offered by more than one system provider and this competition will ensure strong emphasis on service quality and cost of ownership. The handheld terminals also have to be attractive to a large number of potential users, and this means that the terminals must be small enough to fit in a pocket. Battery lifetime is another important consideration, and this coupled with radiation safety requirements limits the maximum radiated EIRP. The terminal G/T is mainly constrained by the gain of the omnidirectional antenna and the noise figure of the RF front end (including input losses). Inmarsat has examined, with the support of industry, a number of Geosynchronous (GSO), Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellite options for the provision of a handheld mobile satellite service. This paper describes the key satellite and orbit parameters and tradeoffs which affect the overall quality of service and the space segment costing. The paper also stresses not only the importance of using and sharing the available mobile frequency band allocations efficiently, but also the key considerations affecting the choice of feeder link bands. The design of the gateways and the terrestrial network is critical to the overall viability of the service, and this paper also examines the key technical parameters associated with the Land Earth Stations (LES), which act as gateways into the Public Switched Telephone Network (PSTN). These not only include the design tradeoffs associated with the LES, but also the different terrestrial network interface options. The paper concludes with a brief description of the satellite propagation conditions associated with the use of handheld terminals. It describes how the handheld results in a number of propagation impairments which are not common to the previous measurements associated with vehicle mounted antennas. These measurements indicate that there is a complex tradeoff between link margin and the elevation angle to the satellite which has a significant impact on the space segment requirements and costing.

Hart, Nick; Haugli, Hans-C.; Poskett, Peter; Smith, K.

49

INMARSAT's personal communicator system  

NASA Technical Reports Server (NTRS)

Inmarsat has been providing near global mobile satellite communications since 1982 and Inmarsat terminals are currently being used in more than 130 countries. The terminals have been reduced in size and cost over the years and new technology has enabled the recent introduction of briefcase sized personal telephony terminals (Inmarsat-M). This trend continues and we are likely to see Inmarsat handheld terminals by the end of the decade. These terminals are called Inmarsat-P and this paper focuses on the various elements required to support a high quality service to handheld terminals. The main system elements are: the handheld terminals; the space segment with the associated orbits; and the gateways to terrestrial networks. It is both likely and desirable that personal handheld satellite communications will be offered by more than one system provider and this competition will ensure strong emphasis on service quality and cost of ownership. The handheld terminals also have to be attractive to a large number of potential users, and this means that the terminals must be small enough to fit in a pocket. Battery lifetime is another important consideration, and this coupled with radiation safety requirements limits the maximum radiated EIRP. The terminal G/T is mainly constrained by the gain of the omnidirectional antenna and the noise figure of the RF front end (including input losses). Inmarsat has examined, with the support of industry, a number of Geosynchronous (GSO), Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellite options for the provision of a handheld mobile satellite service. This paper describes the key satellite and orbit parameters and tradeoffs which affect the overall quality of service and the space segment costing. The paper also stresses not only the importance of using and sharing the available mobile frequency band allocations efficiently, but also the key considerations affecting the choice of feeder link bands. The design of the gateways and the terrestrial network is critical to the overall viability of the service, and this paper also examines the key technical parameters associated with the Land Earth Stations (LES), which act as gateways into the Public Switched Telephone Network (PSTN). These not only include the design tradeoffs associated with the LES, but also the different terrestrial network interface options. The paper concludes with a brief description of the satellite propagation conditions associated with the use of handheld terminals. It describes how the handheld results in a number of propagation impairments which are not common to the previous measurements associated with vehicle mounted antennas. These measurements indicate that there is a complex tradeoff between link margin and the elevation angle to the satellite which has a significant impact on the space segment requirements and costing.

Hart, Nick; Haugli, HANS-C.; Poskett, Peter; Smith, K.

1993-01-01

50

Ultramicrowave communications system, phase 3  

NASA Technical Reports Server (NTRS)

The ultramicrowave communications system program investigated the feasibility of a solid state system that meets the projected space to space requirements, while using the advantages of the 100 to 200 GHz band. The program successfully demonstrated a laboratory model of a high frequency communications system operating between 100 to 200 GHz. In the process, vendor claims for performance specifications of discrete components were evaluated, and a window was provided into system design and integration problems.

1981-01-01

51

Voice communication research evaluation system  

NASA Astrophysics Data System (ADS)

Aircraft voice communications may be degraded by a variety of sources such as electrical and/or acoustical noise, radio interference, jamming and various other forms of distraction. The Voice Communication Research and Evaluation System, located in the Biodynamics and Bioengineering Division of the Aerospace Medical Research Laboratory, has been developed for the comprehensive analysis and enhancement of operational voice communication. The basic system is comprised of a multi-station voice communication network consisting of the USAF standard aircraft intercommunication system, a standard A-19 diluter-demand oxygen regulation system and an on line computer data collection and data analysis system that displays results in real time. The system is housed in a large reverberation chamber containing a programmable sound source capable of reproducing the spectrum and level of any AF operational noise environment. Standardized voice communication effectiveness test materials are used to assess the performance of any aspect of the total voice communication link, however, emphasis is usually placed upon the performance of the aircrew members. This paper will descibe the salient features of this unique system and provide examples of its application to voice communication problems.

McKinley, R. L.

1980-05-01

52

Degree project in Communication Systems  

E-print Network

Degree project in Communication Systems Second level, 30.0 HEC Stockholm, Sweden L I N H V U H O N G DNS Traffic Analysis for Network-based Malware Detection KTH Information and Communication's Programme in Security and Mobile Computing - NordSecMob DNS Traffic Analysis for Network-based Malware

Maguire Jr., Gerald Q.

53

Degree project in Communication Systems  

E-print Network

Degree project in Communication Systems Second level, 30.0 HEC Stockholm, Sweden E R I K E L D H of Information and Communication Technology KTH Royal Institute of Technology Stockholm, Sweden 25 February 2013 of the requirements of the prototype. A middle-ware solution drawing strengths from the services o ered by cloud

Maguire Jr., Gerald Q.

54

Communication, Work Systems and HRD  

ERIC Educational Resources Information Center

Purpose: The purpose of this article is to show the foundational place that communication theory and its practice occupies in functioning work systems. Design/methodology/approach: This paper defines the word communication in terms of the creation and interpretation of displays, describes what it means to have a theoretical foundation for a…

Pace, R. Wayne

2013-01-01

55

Communication Issues in Pervasive Healthcare Systems and  

E-print Network

Chapter 10 Communication Issues in Pervasive Healthcare Systems and Applications Demosthenes provides a systematic analysis of the communication technologies used in healthcare and homecare Vouyioukas Department of Information and Communication Systems Engineering, University of the Aegean

Vouyioukas, Demosthenes

56

49 CFR 193.2519 - Communication systems.  

Code of Federal Regulations, 2014 CFR

...000 liters) storage capacity must have an emergency communication system that provides for verbal communications...operation of safety equipment in time of emergency. The emergency communication system must be independent of and...

2014-10-01

57

49 CFR 193.2519 - Communication systems.  

Code of Federal Regulations, 2011 CFR

...000 liters) storage capacity must have an emergency communication system that provides for verbal communications...operation of safety equipment in time of emergency. The emergency communication system must be independent of and...

2011-10-01

58

49 CFR 193.2519 - Communication systems.  

Code of Federal Regulations, 2013 CFR

...000 liters) storage capacity must have an emergency communication system that provides for verbal communications...operation of safety equipment in time of emergency. The emergency communication system must be independent of and...

2013-10-01

59

49 CFR 193.2519 - Communication systems.  

Code of Federal Regulations, 2012 CFR

...000 liters) storage capacity must have an emergency communication system that provides for verbal communications...operation of safety equipment in time of emergency. The emergency communication system must be independent of and...

2012-10-01

60

Patient Communication: A Multidisciplinary Approach Using Animated Cartoons  

ERIC Educational Resources Information Center

Communication is a major problem in the management of patients. Miscommunication occurs frequently in populations with low reading skills, illiteracy does not completely account for the observed low rates of recall of communicated information. Transmission of the message also plays an important role. Successful strategies to improve communication

Leiner, Marie; Handal, Gilbert; Williams, Darryl

2004-01-01

61

Zinc fate in animal husbandry systems.  

PubMed

Zinc (Zn) is considered in animal production systems as both an essential nutrient and a possible pollutant. While it is generally supplemented at low levels in animal diets, with less than 200 mg kg(-1) in complete feeds, it is under scrutiny due to potential accumulation in the environment. This explains why international regulations limit maximum supplementation levels in animal feeds in a stricter way. This article gives an overview of the current knowledge on the fate of zinc in animal production systems, from animal diets to animal wastes. Some analytical methods can be used for the quantification and qualification of Zn chemical forms: X-ray crystallography, electrospray tandem mass spectrometry, separation techniques, hyphenated techniques… Analysis of chelated forms issued from complex matrices, like hydrolysed proteins, remains difficult, and the speciation of Zn in diluted carriers (premix and feed) is a challenge. Our understanding of Zn absorption has made progress with recent research on ZnT/Zip families and metallothioneins. However, fine-tuned approaches towards the nutritional and metabolic interactions for Zn supplementation in farm conditions still require further studies. The speciation of zinc in pig manure and poultry litter has been a priority as monogastric animals are usually raised under intensive conditions and fed with high quantities of trace minerals, leading to high animal density and elevated quantities of zinc from animal wastes. PMID:25209575

Romeo, A; Vacchina, V; Legros, S; Doelsch, E

2014-11-01

62

Tactical communication systems with the GOSIP architecture  

Microsoft Academic Search

The author proposes a solution to the issue of digital communications interoperability between tactical and strategic (or other) groups within an integrated communications architecture of the future. He proposes two significant changes that permit the tactical systems to be integrated into future communication systems. The first change requires a common set of communication protocols to be used over the communications

1992-01-01

63

Animal production systems in the industrialised world.  

PubMed

The production of food from animal origin is relatively stable in the industrialised world. However, animal production systems are changing dramatically with respect to location, herd size and specialisation. Increased pressure from a critical public is moving animal-based production towards systems such as organic production and loose-housing systems which allow the animals to better express normal behaviour. The focus on food safety promotes systems with a high degree of biosecurity, often associated with an increase in herd size and self-containment. The globalisation of agricultural trade and increased competition also favours an increase in herd size and specialisation. These trends also lead to regions with livestock-dense areas, giving rise to environmental concerns. Therefore, good farming practice regulations and systems to provide a higher level of transparency, such as quality risk management programmes, are being developed. PMID:17094692

Sřrensen, J T; Edwards, S; Noordhuizen, J; Gunnarsson, S

2006-08-01

64

Core systems of geometry in animal minds  

PubMed Central

Research on humans from birth to maturity converges with research on diverse animals to reveal foundational cognitive systems in human and animal minds. The present article focuses on two such systems of geometry. One system represents places in the navigable environment by recording the distance and direction of the navigator from surrounding, extended surfaces. The other system represents objects by detecting the shapes of small-scale forms. These two systems show common signatures across animals, suggesting that they evolved in distant ancestral species. As children master symbolic systems such as maps and language, they come productively to combine representations from the two core systems of geometry in uniquely human ways; these combinations may give rise to abstract geometric intuitions. Studies of the ontogenetic and phylogenetic sources of abstract geometry therefore are illuminating of both human and animal cognition. Research on animals brings simpler model systems and richer empirical methods to bear on the analysis of abstract concepts in human minds. In return, research on humans, relating core cognitive capacities to symbolic abilities, sheds light on the content of representations in animal minds. PMID:22927577

Spelke, Elizabeth S.; Lee, Sang Ah

2012-01-01

65

Animal Behavior & Communication. Animal Life in Action[TM]. Schlessinger Science Library. [Videotape].  

ERIC Educational Resources Information Center

This 23-minute videotape for grades 5-8, presents the myriad of animal life that exists on the planet. Students can view and perform experiments and investigations that help explain animal traits and habits. The way an animal acts or behaves helps it get what it needs to survive. Students find out why some animal behaviors are instinctive while…

2000

66

A conceptual model for particle systems animation  

E-print Network

Particle systems represent a technique for creating a special class of computer generated images. This class of imagery would be difficult or impossible to create using traditional surface based representations found in current computer animation...

Flaherty, Eric Wayne

2012-06-07

67

A Knowledge-Based Computer Animation System  

E-print Network

This paper reproduces part of a doctoral thesis proposal describing the design of a system capable of generating animated drawings in response to a simple story. The representation and interaction of the various sources ...

Kahn, Kenneth M.

68

Advanced satellite communication system  

NASA Technical Reports Server (NTRS)

The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

Staples, Edward J.; Lie, Sen

1992-01-01

69

Video Communications Systems 2 LifeSize Video Communications Systems User Guide  

E-print Network

LifeSize® Video Communications Systems User Guide #12;2 LifeSize Video Communications Systems User-9301 #12;LifeSize Video Communications Systems User Guide 3 Welcome to LifeSize Video Communications Systems LifeSize high definition video communications systems enable anyone with dispersed colleagues

70

Communication synthesis for distributed embedded systems  

Microsoft Academic Search

Abstract: Communication synthesis is an essential step in hardware-software co-synthesis: many embedded systems use custom communication topologies and the communication links are often a significant part of the system cost. This paper describes new techniques for the analysis and synthesis of the communication requirements of embedded systems during co-synthesis. Our analysis algorithm derives delay bounds on communication in the system

Ti-Yen Yen; Wayne Wolf

1995-01-01

71

Acoustical Communications for Wireless Downhole Telemetry Systems  

E-print Network

This dissertation investigates the use of advanced acoustical communication techniques for wireless downhole telemetry systems. Using acoustic waves for downhole telemetry systems is investigated in order to replace the wired communication systems...

Farraj, Abdallah

2012-08-22

72

Communications satellite systems capacity analysis  

NASA Technical Reports Server (NTRS)

Analog and digital modulation techniques are compared with regard to efficient use of the geostationary orbit by communications satellites. Included is the definition of the baseline systems (both space and ground segments), determination of interference susceptibility, calculation of orbit spacing, and evaluation of relative costs. It is assumed that voice or TV is communicated at 14/11 GHz using either FM or QPSK modulation. Both the Fixed-Satellite Service and the Broadcasting-Satellite Service are considered. For most of the cases examined the digital approach requires a satellite spacing less than or equal to that required by the analog approach.

Browne, L.; Hines, T.; Tunstall, B.

1982-01-01

73

Time reversal communication system  

DOEpatents

A system of transmitting a signal through a channel medium comprises digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. The channel medium may be air, earth, water, tissue, metal, and/or non-metal.

Candy, James V. (Danville, CA); Meyer, Alan W. (Danville, CA)

2008-12-02

74

INTRODUCTION Acoustic communication is common among animals and is often  

E-print Network

) and solicit food (Godfray, 1991; Ellis et al., 2009). For acoustic communication to occur, sounds must). Anthropogenic noise produced by roads, construction sites and airports, for instance, might affect breeding, evaluating responses to anthropogenic noise will become increasingly important for effective conservation

Wilson, David R.

75

Coherent OCDMA communication systems  

NASA Astrophysics Data System (ADS)

Coherent optical code division multiple access (OCDMA) technique, where encoding and decoding are based on the phase and amplitude of optical field instead of its intensity, is receiving much attention for the overall superior performance over incoherent OCDMA and the development of compact and reliable en/decoders (E/D) such as spatial light phase modulator (SLPM), superstructured fiber Bragg grating (SSFBG) and multi-port array waveguide grating (AWG)-type E/D. In this paper, we will discuss several recent progresses in coherent OCDMA: a. Novel coding technology such as multi-phase-level SSFBG encoder, 50x50 multiport en/decoder and reconfigurable time domain spectral phase en/decoding; b. New signal modulation formats in OCDMA including DPSK, DQPSK, CSK and M-ary CSK; and c. Field trials of high capacity WDM/OCDMA systems.

Wang, Xu

2012-01-01

76

Animal communication: Tree-hole frogs exploit resonance effects  

Microsoft Academic Search

Animal mating calls that exert a comparatively high sound pressure propagate over greater distances and generally have greater attractive power. Here we show that calling male Bornean tree-hole frogs (Metaphrynella sundana) actively exploit the acoustic properties of cavities in tree trunks that are partially filled with water and which are primarily used as egg-deposition sites. By tuning their vocalizations to

Björn Lardner; Maklarin bin Lakim

2002-01-01

77

33 CFR 127.111 - Communications systems.  

Code of Federal Regulations, 2010 CFR

...Navigation and Navigable Waters 2 2010-07-01...2010-07-01 false Communications systems. 127.111 Section...Navigation and Navigable Waters COAST GUARD, DEPARTMENT...Gas § 127.111 Communications systems. (a) The...

2010-07-01

78

New Paradigms in Wireless Communication Systems  

Microsoft Academic Search

This paper discusses what a new paradigm can be in wireless communication systems of the twenty-first century. First, it suggests two directions for the new paradigm; one is “micro- and nano-device communication system” which is the projected scenario considering that the entities in source and destination have been shrinking throughout the history of wireless communication systems. The second direction is

Shinsuke Hara; Hiroyuki Yomo; Petar Popovski; Kazunori Hayashi

2006-01-01

79

Short-range communication system  

NASA Technical Reports Server (NTRS)

A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

2012-01-01

80

Adapting the Laban Effort System to Design Affect-Communicating Locomotion Path for a  

E-print Network

Adapting the Laban Effort System to Design Affect-Communicating Locomotion Path for a Flying Robot Affect-Communicating Locomotion Path for a Flying Robot Abstract People and animals use various kinds this locomotion-style communication channel for com- municating their states to people. One problem in leveraging

81

Communications Systems for Mobile Robotics  

SciTech Connect

Performance Confirmation is the activity by which the Yucca Mountain Project confirms that the engineered and natural containment barriers of this national nuclear waste repository are performing as predicted, so that an eventual decision to close the repository can be made. This activity involves systems that must be inspected and, in some cases, serviced by mobile robots. This paper discusses systems for underground mobile robot communications, including requirements, environments, options, issues, and down-select criteria. We reviewed a variety of systems, including Slotted Waveguide, Powerline Carrier, Leaky Feeder, Photonic Bandgap Fiber, Free-Space Optics, Millimeter Waves, Terahertz Systems, and RF Systems (including IEEE 802.11 a,b, and g, and Ultra-Wideband radio).

Futterman, J A; Pao, H

2003-12-08

82

Design considerations of terrestrial communications system  

Microsoft Academic Search

We study design considerations, measure of effectiveness (MOE) factors, for tactical communications system. Terrestrial communications system (TCS) architecture for army is described and the link delay performance as a grade of service (GOS) factor is analyzed. One can see that flood search routing algorithm in mesh networks is well suited for tactical communications network and survivability requirements.

Y. C. Park

2007-01-01

83

Study of the neural dynamics for understanding communication in terms of complex hetero systems.  

PubMed

The purpose of the research project was to establish a new research area named "neural information science for communication" by elucidating its neural mechanism. The research was performed in collaboration with applied mathematicians in complex-systems science and experimental researchers in neuroscience. The project included measurements of brain activity during communication with or without languages and analyses performed with the help of extended theories for dynamical systems and stochastic systems. The communication paradigm was extended to the interactions between human and human, human and animal, human and robot, human and materials, and even animal and animal. PMID:25455742

Tsuda, Ichiro; Yamaguchi, Yoko; Hashimoto, Takashi; Okuda, Jiro; Kawasaki, Masahiro; Nagasaka, Yasuo

2014-10-18

84

A Reconfigurable Communications System for Small Spacecraft  

NASA Technical Reports Server (NTRS)

Two trends of NASA missions are the use of multiple small spacecraft and the development of an integrated space network. To achieve these goals, a robust and agile communications system is needed. Advancements in field programmable gate array (FPGA) technology have made it possible to incorporate major communication and network functionalities in FPGA chips; thus this technology has great potential as the basis for a reconfigurable communications system. This report discusses the requirements of future space communications, reviews relevant issues, and proposes a methodology to design and construct a reconfigurable communications system for small scientific spacecraft.

Chu, Pong P.; Kifle, Muli

2004-01-01

85

Short communication Cost-effective abundance estimation of rare animals: Testing performance  

E-print Network

Short communication Cost-effective abundance estimation of rare animals: Testing performance of conservation concern, any cost-effective attempt to estimate absolute abundance will assist status assessments; Sinha, 2002; Rojas-Bracho et al., 2006). The difficulty of providing cost-effective estimates

86

Short communication Pollinators are attracted to mounds created by burrowing animals (marmots)  

E-print Network

Short communication Pollinators are attracted to mounds created by burrowing animals (marmots of insect-pollinated plant species; the number of inflorescences; and the number of pollinators in a marmot colony on the Mongolian steppe. We compared these parameters on and off marmot mounds and searched

Schweik, Charles M.

87

The Roles of Animated Pedagogical Agents' Presence and Nonverbal Communication in Multimedia Learning Environments  

Microsoft Academic Search

We examined how the presence and nonverbal communication of an animated pedagogical agent affects students’ perceptions and learning. College students learned about astronomy either without an agent’s image or with an agent under one of the following conditions: a static agent (S), an agent with deictic movements (D), an agent with facial expressions (E), or an agent with both deictic

Casey Frechette; Roxana Moreno

2010-01-01

88

Animals  

NSDL National Science Digital Library

Explore the wonderful world of animals Listen to the animal sound. See if you can identify the animal.Animal sounds. Explore and find out about different animals.Kids Planet Create a animal report using one of the animals found in the web site.Kids Planet,SeaWorld/animals Create a picture of your animal examples are found...Your big backyard ...

Mrs. Unsworth

2005-03-31

89

COMMANIMATION : a speech-controlled animation system  

E-print Network

In order to make the task of animation creation easy, a different approach should be presented to the user. This thesis describes a new approach to animation creation. In this approach, the representation of animation is ...

Kho, Nancy Ellen, 1981-

2004-01-01

90

The Aerospace Corporation 2009 Communication Satellite Systems  

E-print Network

© The Aerospace Corporation 2009 Communication Satellite Systems Trends and Network Aspects Paul://www.aero.org/ Lee Center, Caltech 13 April 2009 #12;22 Communication Satellites · Brief History by Decade · Trends: ­ Communication Satellites, fifth edition, by D. Martin, P. Anderson, L. Bartamian, Aerospace / AIAA Press, 2006

Low, Steven H.

91

Automobile inspection system based on wireless communication  

Microsoft Academic Search

This paper aims to research the Automobile Inspection System based on Wireless Communication, and suggests an overall design scheme which uses GPS for speed detection and Bluetooth and GPRS for communication. The communication between PDA and PC was realized by means of GPRS and TCP\\/IP; and the hardware circuit and software for detection terminal were devised by means of JINOU-3264

Changyun Miao; Chunqing Ye

2010-01-01

92

Tools for studying animal behaviour: validation of dive profiles relayed via the Argos satellite system  

E-print Network

Tools for studying animal behaviour: validation of dive profiles relayed via the Argos satellite satellite system (http://www.argosinc.com). Behavioural data relayed remotely via the Argos satellite system of their time submerged, further limiting the time available for communication with satel- lites. The problem

Hays, Graeme

93

Human Factors Aspects of Power System Flow Animation  

E-print Network

Human Factors Aspects of Power System Flow Animation Douglas A. Wiegmann, Gavin R. Essenberg experimental results associated with human factors aspects of using animation to display electric power system. Index Terms--Power System Operations and Planning, Power System Visualization, Animation, Human Factors

94

Transition From NASA Space Communication Systems to Commerical Communication Products  

NASA Technical Reports Server (NTRS)

Transitioning from twenty-five years of space communication system architecting, engineering and development to creating and marketing of commercial communication system hardware and software products is no simple task for small, high-tech system engineering companies whose major source of revenue has been the U.S. Government. Yet, many small businesses are faced with this onerous and perplexing task. The purpose of this talk/paper is to present one small business (LinCom) approach to taking advantage of the systems engineering expertise and knowledge captured in physical neural networks and simulation software by supporting numerous National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) projects, e.g., Space Shuttle, TDRSS, Space Station, DCSC, Milstar, etc. The innovative ingredients needed for a systems house to transition to a wireless communication system products house that supports personal communication services and networks (PCS and PCN) development in a global economy will be discussed. Efficient methods for using past government sponsored space system research and development to transition to VLSI communication chip set products will be presented along with notions of how synergy between government and industry can be maintained to benefit both parties.

Ghazvinian, Farzad; Lindsey, William C.

1994-01-01

95

Software-defined Quantum Communication Systems  

SciTech Connect

We show how to extend the paradigm of software-defined communication to include quantum communication systems. We introduce the decomposition of a quantum communication terminal into layers separating the concerns of the hardware, software, and middleware. We provide detailed descriptions of how each component operates and we include results of an implementation of the super-dense coding protocol. We argue that the versatility of software-defined quantum communication test beds can be useful for exploring new regimes in communication and rapidly prototyping new systems.

Humble, Travis S [ORNL] [ORNL; Sadlier, Ronald J [ORNL] [ORNL

2013-01-01

96

PVS0071 Quality assurance and communication on Animal Welfare web-based teaching material, 3.0 credits  

E-print Network

PVS0071 Quality assurance and communication on Animal Welfare web- based teaching material, 3 on the evaluation of web-based teaching material; · Reflect on pedagogical concepts in the use of web-based teaching materials; · Communicate on animal welfare issues to central administrations as well as to the young average

97

A review of mobile satellite communication systems  

NASA Astrophysics Data System (ADS)

This article describes mobile satellite systems in the planning or development stage such as MSAT, AMSC and Geostar and mobile satellite communication experiments such as PRODAT. Studies on the system such as T-SAT are also reviewed. In addition, Japanese ETS-V and ETS-VI are described. The development of mobile-satellite communication systems is promoted along with those of communication and satellite technologies.

Kondo, Kimio

1990-03-01

98

Software-defined Quantum Communication Systems  

E-print Network

Quantum communication systems harness modern physics through state-of-the-art optical engineering to provide revolutionary capabilities. An important concern for quantum communication engineering is designing and prototyping these systems to evaluate proposed capabilities. We apply the paradigm of software-defined communication for engineering quantum communication systems to facilitate rapid prototyping and prototype comparisons. We detail how to decompose quantum communication terminals into functional layers defining hardware, software, and middleware concerns, and we describe how each layer behaves. Using the super-dense coding protocol as an example, we describe implementations of both the transmitter and receiver, and we present results from numerical simulations of the behavior. We conclude that software-defined quantum communication provides a robust framework in which to explore the large design space offered by this new regime of communication.

Travis S. Humble; Ronald J. Sadlier

2014-10-20

99

Smart Grid Communications System Blueprint  

NASA Astrophysics Data System (ADS)

Telecommunications operators are well versed in deploying 2G and 3G wireless networks. These networks presently support the mobile business user and/or retail consumer wishing to place conventional voice calls and data connections. The electrical power industry has recently commenced transformation of its distribution networks by deploying smart monitoring and control devices throughout their networks. This evolution of the network into a `smart grid' has also motivated the need to deploy wireless technologies that bridge the communication gap between the smart devices and information technology systems. The requirements of these networks differ from traditional wireless networks that communications operators have deployed, which have thus far forced energy companies to consider deploying their own wireless networks. We present our experience in deploying wireless networks to support the smart grid and highlight the key properties of these networks. These characteristics include application awareness, support for large numbers of simultaneous cell connections, high service coverage and prioritized routing of data. We also outline our target blueprint architecture that may be useful to the industry in building wireless and fixed networks to support the smart grid. By observing our experiences, telecommunications operators and equipment manufacturers will be able to augment their current networks and products in a way that accommodates the needs of the emerging industry of smart grids and intelligent electrical networks.

Clark, Adrian; Pavlovski, Chris

2010-10-01

100

Apollo experience report: Lunar module communications system  

NASA Technical Reports Server (NTRS)

The development of the lunar module communications system is traced from the initial concept to the operational system used on manned lunar missions. The problems encountered during the development, the corrective actions taken, and recommendations for similar equipment in future programs are included. The system was designed to provide communications between the lunar module and the manned space flight network, between the lunar module and the command and service module, and between the lunar module and the extravehicular crewmen. The system provided the equipment necessary for voice, telemetry, and television communications; ranging information; and various communications links.

Dietz, R. H.; Rhoades, D. E.; Davidson, L. J.

1972-01-01

101

Automatic communication signal monitoring system  

NASA Technical Reports Server (NTRS)

A system is presented for automatic monitoring of a communication signal in the RF or IF spectrum utilizing a superheterodyne receiver technique with a VCO to select and sweep the frequency band of interest. A first memory is used to store one band sweep as a reference for continual comparison with subsequent band sweeps. Any deviation of a subsequent band sweep by more than a predetermined tolerance level produces an alarm signal which causes the band sweep data temporarily stored in one of two buffer memories to be transferred to long-term store while the other buffer memory is switched to its store mode to assume the task of temporarily storing subsequent band sweeps.

Bernstein, A. J. (inventor)

1978-01-01

102

MUAN: A Stop Motion Animation System Margareth Catoia Varela1  

E-print Network

MUAN: A Stop Motion Animation System Margareth Catoia Varela1 , Luiz Velho1 , Bruno Madeira1,lvelho,madeira,hedlena }@impa.br, marcos@animamundi.com.br Abstract. MUAN is a Stop Motion Animation System for Education. The MUAN system allows animation movie production offering an integrated kit of hardware and software

Paris-Sud XI, Université de

103

Group Support in Multimedia Communications Systems  

E-print Network

: Communication among multiple entities is becoming more and more widespread in computing and telecommunications. Although many existing communications protocols and services do offer some limited support for multicast or group communication, the new requirements of multipeer applications make it difficult to find efficient and comprehensive solutions. In this paper we discuss the required characteristics of group services and survey the extent of the support provided by today's services and protocols. In addition, a brief outline of standardisation efforts in this area within ISO and ITU is given and selected examples of research projects which deal with different aspects of group communication are presented. 1 Introduction The use of computers for interpersonal communication among multiple users has provoked a new trend called group communication. Although group communication is also used for distributed file systems, distributed data bases, fault tolerant systems, etc., the main req...

A. Mauthe; G. Coulson; D. Hutchison; S. Namuye

104

Animal biocalorimeter and waste management system  

NASA Technical Reports Server (NTRS)

A biocalorimeter and waste management system is provided for making metabolic heat release measurements of animals or humans in a calorimeter (enclosure) using ambient air as a low velocity source of ventilating air through the enclosure. A shroud forces ventilating air to pass over the enclosure from an end open to ambient air at the end of the enclosure opposite its ventilating air inlet end and closed around the inlet end of the enclosure in order to obviate the need for regulating ambient air temperature. Psychrometers for measuring dry- and wet-bulb temperature of ventilating air make it possible to account for the sensible and latent heat additions to the ventilating air. A waste removal system momentarily recirculates high velocity air in a closed circuit through the calorimeter wherein a sudden rise in moisture is detected in the ventilating air from the outlet.

Poppendiek, Heinz F. (Inventor); Trimailo, William R. (Inventor)

1995-01-01

105

SRS Computer Animation and Drive Train System  

NASA Technical Reports Server (NTRS)

The spinning rocket simulator (SRS) is an ongoing project at Oral Roberts University. The goal of the SRS is to gather crucial data concerning a spinning rocket under thrust for the purpose of analysis and correction of the coning motion experienced by this type of spacecraft maneuver. The computer animation simulates a virtual, scale model of the component of the SRS that represents the spacecraft itself. This component is known as the (VSM), or virtual spacecraft model. During actual physical simulation, this component of the SRS will experience a coning. The goal of the animation is to cone the VSM within that range to accurately represent the motion of the actual simulator. The drive system of the SRS is the apparatus that turns the actual simulator. It consists of a drive motor, motor mount and chain to power the simulator into motion. The motor mount is adjustable and rigid for high torque application. A digital stepper motor controller actuates the main drive motor for linear acceleration. The chain transfers power from the motor to the simulator via sprockets on both ends.

Arthun, Daniel; Schachner, Christian

2001-01-01

106

How do communication systems emerge?  

PubMed Central

Communication involves a pair of behaviours—a signal and a response—that are functionally interdependent. Consequently, the emergence of communication involves a chicken-and-egg problem: if signals and responses are dependent on one another, then how does such a relationship emerge in the first place? The empirical literature suggests two solutions to this problem: ritualization and sensory manipulation; and instances of ritualization appear to be more common. However, it is not clear from a theoretical perspective why this should be the case, nor if there are any other routes to communication. Here, we develop an analytical model to examine how communication can emerge. We show that: (i) a state of non-interaction is evolutionarily stable, and so communication will not necessarily emerge even when it is in both parties' interest; (ii) the conditions for sensory manipulation are more stringent than for ritualization, and hence ritualization is likely to be more common; and (iii) communication can arise by a third route, when the intention to communicate can itself be communicated, but this may be limited to humans. More generally, our results demonstrate the utility of a functional approach to communication. PMID:22217724

Scott-Phillips, Thomas C.; Blythe, Richard A.; Gardner, Andy; West, Stuart A.

2012-01-01

107

A Wireless Communications Systems Laboratory Course  

ERIC Educational Resources Information Center

A novel wireless communications systems laboratory course is introduced. The course teaches students how to design, test, and simulate wireless systems using modern instrumentation and computer-aided design (CAD) software. One of the objectives of the course is to help students understand the theoretical concepts behind wireless communication

Guzelgoz, Sabih; Arslan, Huseyin

2010-01-01

108

Protein Communication System: Evolution and Genomic Structure  

Microsoft Academic Search

We develop a mathematical model of the genetic information storage and transmission system and investigate its properties. Breaking with tradition, whereas the genetic information storage and transmission apparatus is conventionally modelled as an engineering communication system with the DNA sequence as the input and the amino acid chain as the output, in this paper the genetic communication model is viewed

Nidhal Bouaynaya; Dan Schonfeld

2007-01-01

109

A Speech Driven Face Animation System Based on Machine Learning  

Microsoft Academic Search

Lip synchronization is the key issue in speech driven face animation system. In this paper, some clustering and machine learning methods are combined together to estimate face animation parameters from audio sequences and then apply the learning results to MPEG-4 based speech driven face animation system. Based on a large recorded audio-visual database, an unsupervised cluster algorithm is proposed to

CHEN Yi-Qiang; GAO Wen; WANG Zhao-Qi; JIANG Da-Long

2003-01-01

110

TANGO: A FRAMEWORK AND SYSTEM FOR ALGORITHM ANIMATION  

Microsoft Academic Search

Algorithm animation is the process of abstracting the data, operations, and semantics of computer programs, and then creating animated graphical views of those abstractions. Although a handful of algorithm animation systems have been developed in recent years, relatively little work has been done on the theoretical foundations of such systems. In this work we develop a conceptual framework with formal

John T. Stasko

1990-01-01

111

Degree project in Communication Systems  

E-print Network

cell phone manufacturers have been releasing cell phones equipped with Near Field Communication (NFC with an NFC interface Smart Door Lock KTH Information and Communication Technology #12;Smart Door Lock A first prototype of a networked power lock controller with an NFC interface Rafid Karim and Haidara Al-Fakhri 2013

Maguire Jr., Gerald Q.

112

Sign Language: A Communication System.  

ERIC Educational Resources Information Center

The manual is intended as a course resource to help hearing secondary students learn to communicate with deaf peers or family members. The total communication approach is described and reasons for its use advanced. An introductory section explains the philosophy, general goals, and program objectives of the course. Ten lesson plans are then…

New York State Education Dept., Albany. Bureau of Curriculum Development.

113

A Distant Solar System (Artist's Concept Animation)  

NASA Technical Reports Server (NTRS)

This animation portrays an artist's concept of a distant hypothetical solar system, about the same age as our own. It begins close to the star, and then moves out past a number of planets. Though 'extrasolar' planets are too small to be seen with telescopes, astronomers have detected more than 100 gas giants like Jupiter via their gravitational tug on their parent stars.

The view pulls back to reveal the outer fringes of the system and a ring of dusty debris that circles the star. This debris is all that remains of the planet-forming disk from which the planets evolved.

Planets are formed when dusty material in a large disk surrounding a young star clumps together. Leftover material is eventually blown out by solar wind or pushed out by gravitational interactions with planets. Billions of years later, only an outer disk of debris remains.

These outer debris disks are too faint to be imaged directly by visible-light telescopes. They are washed out by the glare of the Sun. However, NASA's Spitzer Space Telescope can detect their heat, or excess thermal emission, in infrared light. This allows astronomers to study the aftermath of planet building in distant solar systems like our own.

2004-01-01

114

Data-base driven graphics animation and simulation system  

SciTech Connect

Most attempts at the graphics animation of data involve rather large and expensive development of problem-specific systems. This paper discusses a general graphics animation system created to be a tool for the design of a wide variety of animated simulations. By using relational data base storage of graphics and control information, considerable flexibility in the design and development of animated displays is achieved.

Stewart, H.D.; Curtis, J.N.

1985-01-01

115

Satellite Communication Hardware Emulation System (SCHES)  

NASA Technical Reports Server (NTRS)

Satellite Communication Hardware Emulator System (SCHES) is a powerful simulator that emulates the hardware used in TDRSS links. SCHES is a true bit-by-bit simulator that models communications hardware accurately enough to be used as a verification mechanism for actual hardware tests on user spacecraft. As a credit to its modular design, SCHES is easily configurable to model any user satellite communication link, though some development may be required to tailor existing software to user specific hardware.

Kaplan, Ted

1993-01-01

116

COMMUNICATION SYSTEMS AND STUDY METHOD FOR ACTIVE DISTRIBUTION POWER SYSTEMS  

E-print Network

of communication systems, and the main communication technologies and protocols on each corresponding layer are introduced. Some newly developed communication techniques, like Ethernet, are discussed with reference and the power system depend on many aspects, such as related protocols, access technologies, and transmission

Chen, Zhe

117

A 1000+ channel bionic communication system.  

PubMed

The wireless electronic nervous system interface known as the functional electrical stimulation-battery powered bion system is being developed at the Alfred Mann Foundation. It contains a real-time propagated wave micro-powered multichannel communication system. This system is designed to send bi-directional messages between an external master controller unit (MCU), and each one of a group of injectable stimulator-sensor battery powered bion implants (BPB). The system is capable of communicating in each direction about 90 times per second using a structure of 850 time slots within a repeating 11 millisecond time window. The system's total Time Division Multiple Access (TDMA) communication capability is about 77,000 two-way communications per second on a single 5 MHz wide radio channel. Each time slot can be used by one BPB, or shared alternately by two or more BPBs. Each bidirectional communication consists of a 15 data bit message sent from the MCU sequentially to each BPB and 10 data bit message sent sequentially from each BPB to the MCU. Redundancy bits are included to provide error detection and correction. This communication system is designed to draw only a few microamps from the 3.6 volt, 3.0 mAHr lithium ion (LiIon) battery contained in each BPB, and the majority of the communications circuitry is contained within a 1.4x5 mm integrated circuit. PMID:17947078

Schulman, Joseph H; Mobley, J Phil; Wolfe, James; Stover, Howard; Krag, Adrian

2006-01-01

118

Integrated defense communications system antijamming antenna system  

NASA Astrophysics Data System (ADS)

The isolation of mainbeam and sidelobe jamming signals from the desired signal being relayed by microwave communication links is accomplished by an antijamming antenna comprising a flat radome, a curved reflector and a transmit dipole. Positioned adjacent the dipole is a monopulse feed and comparator for main-beam jammers (dual-plane monopulse, multi-mode multilayer feed). Also forming part of the integrated antenna are auxiliary units for near-sidelobe and far-sidelobe jammers. An alternative embodiment includes a Cassegrain grating sub-reflector. Since the direction of the desired incoming signal in microwave communication links is precisely known, the antijamming antenna uses azimuth and elevation monopulse to make a spatial distinction between the desired incoming signal and the jamming signals. The antijamming antenna system outputs: a sum, azimuth difference elevation difference signals and isolated near-sidelobe jamming signals and far-sidelobe jamming signals on output ports which allow an adaptive processor to place pattern nulls on jammers located in the mainbeam and sidelobe region of the antenna.

Hannan, P. W.

1984-09-01

119

Coexistence of broadband power line communication systems  

Microsoft Academic Search

Recent progress in home networks enhances the application of broadband power line communication (BPL) since it does not require any installation of new communication lines or outlets. However, high-density distribution of BPL devices may bring down the access quality. Besides, the electromagnetic field radiating from the power line may cause interference with other radio systems. Thus, the objective of this

Biao YANG; Ying-hua LÜ; Hong-xin ZHANG

2009-01-01

120

How to Bootstrap a Human Communication System  

ERIC Educational Resources Information Center

How might a human communication system be bootstrapped in the absence of conventional language? We argue that motivated signs play an important role (i.e., signs that are linked to meaning by structural resemblance or by natural association). An experimental study is then reported in which participants try to communicate a range of pre-specified…

Fay, Nicolas; Arbib, Michael; Garrod, Simon

2013-01-01

121

29 CFR 1915.85 - Vessel radar and communication systems.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Vessel radar and communication systems. 1915.85...Working Conditions § 1915.85 Vessel radar and communication systems. (a) The employer shall service each vessel's radar and communication systems in...

2014-07-01

122

29 CFR 1915.85 - Vessel radar and communication systems.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Vessel radar and communication systems. 1915.85...Working Conditions § 1915.85 Vessel radar and communication systems. (a) The employer shall service each vessel's radar and communication systems in...

2013-07-01

123

29 CFR 1915.85 - Vessel radar and communication systems.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Vessel radar and communication systems. 1915.85...Working Conditions § 1915.85 Vessel radar and communication systems. (a) The employer shall service each vessel's radar and communication systems in...

2012-07-01

124

Simulating Rain Fade In A Communication System  

NASA Technical Reports Server (NTRS)

Automated, computer-controlled assembly of electronic equipment developed for use in simulation testing of downlink portion of Earth/satellite microwave digital communication system. Designed to show effects upon performance of system of rain-induced fading in received signal and increases in transmitted power meant to compensate for rain-induced fading. Design of communication system improved iteratively in response to results of simulations, leading eventually to design ensuring clear, uninterrupted transmission of digital signals.

Shalkhauser, Kurt A.; Nagy, Lawrence A.; Svoboda, James K.

1994-01-01

125

Preliminary Thoughts on Netted Cable Communication Systems.  

ERIC Educational Resources Information Center

There are five categories of cable communication systems: Conventional Community Antenna Television (CATV), Pay-TV, Subscriber Response Systems, Electronic Information Handling Systems, and Two-Way Audio/Visual Systems. CATV and Pay-TV systems are designed for the one-way transmission of programs, the former providing for better quality…

Eldridge, Frank; Mason, William

126

SWINE PRODUCTION SYSTEMS: ANIMAL WELFARE CONSIDERATIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A general public perception is that it is easy to visualize when an animals welfare is adequate. Scientifically, this determination is quite difficult. The difficulty resides in our ability to objectively assess the animals physical and psychological state; as well as to determine the difference b...

127

Underground communications and tracking systems update  

SciTech Connect

Today, when it comes to having systems to communicate with track and locate underground coal miners, mining companies have many equipment choices, as a direct response to the USA's 2006 MINER Act and the West Virginia Legislative Rule 56-4-8. Coal Age spoke to several companies about their leaky feeder and purely wireless systems which are either approved by the US MSHA or have been submitted for approval. The article gives details of: a UHF leaky feeder system developed by Pillar Innovations, designed to exit a mine at multiple points and then tie the leads back together on the surface; the Venture/Helicomm MineTrader system for tracking, monitoring and emergency messaging for mines; Rajant Corp.'s BreadCrumb wireless system using battery-powered wireless access nodes that enable voice and data communications across a self-healing network; the SubterraCom Wireless Solution's communications systems; a wireless mesh peer-to-peer communications system and an ultra widebade (UWB)-base real-time location tracking system from L-3 Communications; and VHF and UHF leaky feeder amplifiers from Tunnel Radio. MSHA approved communications and tracking systems are tabulated. 11 photos., 1 tab.

Fiscor, S.

2008-01-15

128

Voice communication research and evaluation system  

NASA Astrophysics Data System (ADS)

The basic system is comprised of a multistation voice communication network consisting of the USAF standard aircraft intercommunication system, a standard A-19 diluter demand oxygen regulation system and an on line computer data collection and data analysis system that displays results in real time. The system is housed in a large reverberation chamber containing a programmable sound source capable of reproducing the spectrum and level of any AF operational noise environment. Standardized voice communication effectiveness test materials are used to assess the performance of any aspect of the total voice communication link, however, emphasis is usually placed upon the performance of the aircrew members. Examples of its application to voice communication problems are provided.

McKinley, R. L.

1981-06-01

129

Automobile inspection system based on wireless communication  

NASA Astrophysics Data System (ADS)

This paper aims to research the Automobile Inspection System based on Wireless Communication, and suggests an overall design scheme which uses GPS for speed detection and Bluetooth and GPRS for communication. The communication between PDA and PC was realized by means of GPRS and TCP/IP; and the hardware circuit and software for detection terminal were devised by means of JINOU-3264 Bluetooth Module after analyzing the Bluetooth and its communication protocol. According to the results of debugging test, this system accomplished GPRS based data communication and management as well as the real-time detection on auto safety performance parameters in crash test via PC, whereby the need for mobility and reliability was met and the efficiency and level of detection was improved.

Miao, Changyun; Ye, Chunqing

2010-07-01

130

QDoes this system, using DDG feedings, produce satisfactory animal performance? Additionally, since the animals were  

E-print Network

QDoes this system, using DDG feedings, produce satisfactory animal performance? Additionally, since the animals were fed very limited starch, were CLA levels similar to grass-only finished cattle? AResults in feed- lots. Background Due to rising costs of conventional feedstuffs, more focus has been put

Debinski, Diane M.

131

Animation  

NSDL National Science Digital Library

Animation is making a splash with the recent box office hit, Shrek 2. This Topic in Depth explores how animation works, it's history and the entertaining as well as academic applications of animation. The first website provides a basic overview of digital cinema (1). More information on animation can be found on the second website (2). Digital Media FX provides this history (3 ) of animation. The Library of Congress has also put together a nice website (4 ) with some historical artifacts that for demonstrating a "a variety of elements that go into the creative process of developing and interpreting animated motion pictures." The fourth website provides an extensive list of online resources and academic uses for animation such as Chemistry, Evolution, Genetics, and Physics. (5 ). This fifth website posts the winners of the 2004 Character Animation Technologies competition (6 ). And finally, Slashdot has a nice expose on the Mathematics of Futurama (7).

132

Introduction to Communication Systems Upamanyu Madhow  

E-print Network

.3.1 Limiter-Discriminator Demodulation . . . . . . . . . . . . . . . . . . . . . 94 3.3.2 FM Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 3.3.3 Concept synthesis for FM . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 3.6 Some Analog Communication Systems . . . . . . . . . . . . . . . . . . . . . . . . 112 3.6.1 FM

Madhow, Upamanyu

133

Electromagnetic Characterization of MIMO Communication Systems  

E-print Network

electromagnetic interactions between the antenna arrays and the environment. To dissect the influence of various and the complex electromagnetic interactions between the antennas and the environment. SingleElectromagnetic Characterization of MIMO Communication Systems Kapil R. Dandekar, Sumant Kawale

Dong, Liang

134

Space Station multiple access communications system  

NASA Technical Reports Server (NTRS)

The development of a multiple access communications system (MACS) for the space-to-space communications on the Space Station is discussed. The communications capabilities of the FHMA, CDMA, TDMA, SDMA, and FDMA techniques are evaluated; FDMA was selected for the space-to-space communications on the Space Station because of its lower complexity and growth capability. The proposed space-to-space multiple access system for the Space Station is a digitally modulated Ku-band FDMA system with a distributed architecture; this system would transmit on frequencies between 13.4 and 13.7 GHz and receive on frequencies between 14.6 and 14.89 GHz, and the bandwidth will support seven high-data-rate users and 12 low-data-rate users. The IF components and antennas for the MACS are examined. A multiple access breadboard design is described.

Olson, Nanci A.

1986-01-01

135

Space Station multiple access communications system  

NASA Astrophysics Data System (ADS)

The development of a multiple access communications system (MACS) for the space-to-space communications on the Space Station is discussed. The communications capabilities of the FHMA, CDMA, TDMA, SDMA, and FDMA techniques are evaluated; FDMA was selected for the space-to-space communications on the Space Station because of its lower complexity and growth capability. The proposed space-to-space multiple access system for the Space Station is a digitally modulated Ku-band FDMA system with a distributed architecture; this system would transmit on frequencies between 13.4 and 13.7 GHz and receive on frequencies between 14.6 and 14.89 GHz, and the bandwidth will support seven high-data-rate users and 12 low-data-rate users. The IF components and antennas for the MACS are examined. A multiple access breadboard design is described.

Olson, Nanci A.

136

HICCUPS: Hidden Communication System for Corrupted Networks  

Microsoft Academic Search

This article presents HICCUPS (HIdden Communication system for CorrUPted networkS), a steganographic system dedicated to shared medium networks including wireless local area networks. The novelty of HICCUPS is: usage of secure telecommunications network armed with cryptographic mechanisms to provide steganographic system and proposal of new protocol with bandwidth allocation based on corrupted frames. All functional parts of the system and

KRZYSZTOF SZCZYPIORSKI

137

Broadband CDMA for personal communications systems  

Microsoft Academic Search

Multipath propagation in a broadband CDMA environment is described. A propagation model for broadband spread-spectrum signals is presented. Experimental results relating to the sharing of the band by fixed service microwave users and mobile personal communications network (PCN) users are discussed. Field tests indicate that PCN systems can provide high-quality communications when sharing the spectrum with fixed-service microwave systems in

D. L. Schilling; L. B. Milstein; R. L. Pickholtz; F. Bruno; E. Kanterakis; M. Kullback; V. Erceg; W. Biederman; D. Fishman; D. Salerno

1991-01-01

138

Degree project in Communication Systems  

E-print Network

according to CAN protocols must be transferred by means of Ethernet A main issue is that CAN is time B R A H I M Ethernet in Steer-by-wire Applications KTH Information and Communication Technology #12;Ethernet in Steer-by-wire Applications Muhammad Ibrahim muhibr@kth.se July 18, 2011 Supervisors Prof

Maguire Jr., Gerald Q.

139

Degree project in Communication Systems  

E-print Network

A N Performance evaluation of security mechanisms in Cloud Networks KTH Information and Communication Technology #12;Performance evaluation of security mechanisms in Cloud Networks Anand Kannan 30th July - 2012 of the overall problem, specifically a comprehensive, tightly integrated, and multi-level security architecture

Maguire Jr., Gerald Q.

140

Degree project in Communication Systems  

E-print Network

) or amblyopia (lazy eye). However, applying this technology to clinical cases will require further development A N A P U L I D O Ophthalmic Diagnostics Using Eye Tracking Technology KTH Information and Communication Technology #12;Ophthalmic Diagnostics Using Eye Tracking Technology Master of Science Thesis

Maguire Jr., Gerald Q.

141

Design for communications center monitor & control system  

Microsoft Academic Search

Communications center monitor & control system, including power supply sub-system, environment sub-system, fire sub-system, security sub-system and so on, is widely used in school, enterprise, government and other areas. The control system designed by this paper can get temperature and humidity information from RS485 sensor of temperature-humidity. From measuring gate sensor, smoke sensor and leak-water senor, the control system can

Zhigang Lv; Cuixia Liu

2010-01-01

142

Tags, wireless communication systems, tag communication methods, and wireless communications methods  

DOEpatents

Tags, wireless communication systems, tag communication methods, and wireless communications methods are described. In one aspect, a tag includes a plurality of antennas configured to receive a plurality of first wireless communication signals comprising data from a reader, a plurality of rectifying circuits coupled with. respective individual ones of the antennas and configured to provide rectified signals corresponding to the first wireless communication signals, wherein the rectified signals are combined to produce a composite signal, an adaptive reference circuit configured to vary a reference signal responsive to the composite signal, a comparator coupled with the adaptive reference circuit and the rectifying circuits and configured to compare the composite signal with respect to the reference signal and to output the data responsive to the comparison, and processing circuitry configured to receive the data from the comparator and to process the data.

Scott; Jeff W. (Pasco, WA), Pratt; Richard M. (Richland, WA)

2006-09-12

143

Talk to the Virtual Hands: Self-Animated Avatars Improve Communication in Head-Mounted Display Virtual  

E-print Network

Talk to the Virtual Hands: Self-Animated Avatars Improve Communication in Head-Mounted Display in the amount of body gestures that participants use with and without the head-mounted display, and we discuss in real time, so the avatar is self-animated. We conducted two experiments to investigate (a) whether head-mounted

144

[Develop mine communications system]. Final technical report  

SciTech Connect

The objective of this project was to develop, design, and build a system prototype to demonstrate the practicality of two-way, wireless through-the-earth communications between the interior of a mine and the surface. The system was to communicate data for process and environment monitoring and control, and provide real-time voice communication for emergency situations and for daily operations use. Transmitters and receivers were designed, built, and tested in actual mines. A wireless in-mine communications system was also developed. The feasibility of the concept and the marketability of the product were successfully demonstrated. Additional work must be done to make the product suitable for, and marketable to, the coal mining industry.

Meiksin, Z.H.

1998-09-15

145

Data analysis using a data base driven graphics animation system  

SciTech Connect

A graphics animation system has been developed at the Idaho National Engineering Laboratory (INEL) to assist engineers in the analysis of large amounts of time series data. Most prior attempts at computer animation of data involve the development of large and expensive problem-specific systems. This paper discusses a generalized interactive computer animation system designed to be used in a wide variety of data analysis applications. By using relational data base storage of graphics and control information, considerable flexibility in design and development of animated displays is achieved.

Schwieder, D.H.; Stewart, H.D.; Curtis, J.N.

1985-01-01

146

Degree project in Communication Systems  

E-print Network

K U R I Y O a n d M O H A M M A D A B D U L L A Toward a Network Based 3D Printing Service KTH Information and Communication Technology #12;Toward a Network Based3D Printing Service Laurier Ndikuriyo realized and is left as future work. Keywords: 3D-printing, MakerBot Thing-o-Matic, Replicatorg, LAMP, Open

Maguire Jr., Gerald Q.

147

Security alarm communication and display systems development  

Microsoft Academic Search

Sandia National Laboratories (SNL) has, as lead Department of Energy (DOE) physical security laboratory, developed a variety of alarm communication and display systems for DOE and Department of Defense (DOD) facilities. This paper briefly describes some of the systems developed and concludes with a discussion of technology relevant to those currently designing, developing, implementing, or procuring such a system. Development

Waddoups

1990-01-01

148

Animation  

Microsoft Academic Search

\\u000a Ah, animation! Where would we be without the likes of Disney, Warner Bros., Walter Lanz, Hanna-Barbera, and dozens more like\\u000a them? For many people, animation is the reason to get involved with Flash as a creative outlet. This makes perfect sense, because Flash began life more than a decade ago\\u000a as an animation tool. Supplemental features like ActionScript, XML parsing,

Tom Green; David Stiller

149

Full-duplex optical communication system  

NASA Technical Reports Server (NTRS)

A method of full-duplex electromagnetic communication wherein a pair of data modulation formats are selected for the forward and return data links respectively such that the forward data electro-magnetic beam serves as a carrier for the return data. A method of encoding optical information is used wherein right-hand and left-hand circular polarizations are assigned to optical information to represent binary states. An application for an earth to low earth orbit optical communications system is presented which implements the full-duplex communication and circular polarization keying modulation format.

Shay, Thomas M. (Inventor); Hazzard, David A. (Inventor); Horan, Stephen (Inventor); Payne, Jason A. (Inventor)

2004-01-01

150

An advanced, low cost, GPS-based animal tracking system  

Technology Transfer Automated Retrieval System (TEKTRAN)

An improved GPS-based animal tracking system is needed to meet quickly-evolving ecological research and natural resource management demands. Commercially-available tracking systems lack the data storage capacity needed to frequently collect animal location data (e.g., at less than 5-minute interval...

151

Children's interactions with animated agents in an intelligent tutoring system  

E-print Network

Children's interactions with animated agents in an intelligent tutoring system Judy Robertson, Beth Buccleuch Place, Edinburgh EH8 9LW, UK. judyr@inf.ed.ac.uk Abstract. Although animated pedagogical agents are frequently found in intelligent tutoring systems and interactive learning environments, their effect on users

Wiemer-Hastings, Peter

152

RESTRAINING SYSTEM FOR PLETHYSMOGRAPHY IN SMALL ANIMALS  

EPA Science Inventory

A restraining technique for immobilizing awake guinea pigs and rats during physiological measurements is described. The basic device consists of an adjustable acrylic holder that supports the animal in a standing position while restricting movement of the four legs. The holder al...

153

A native IP satellite communications system  

NASA Astrophysics Data System (ADS)

? In the framework of ESA's ARTES-5 program the Institute of Applied Systems Technology (Joanneum Research) in cooperation with the Department of Communications and Wave Propagation has developed a novel meshed satellite communications system which is optimised for Internet traffic and applications (L*IP—Local Network Interconnection via Satellite Systems Using the IP Protocol Suite). Both symmetrical and asymmetrical connections are supported. Bandwidth on demand and guaranteed quality of service are key features of the system. A novel multi-frequency TDMA access scheme utilises efficient methods of IP encapsulation. In contrast to other solutions it avoids legacy transport network techniques. While the DVB-RCS standard is based on ATM or MPEG transport cells, the solution of the L*IP system uses variable-length cells which reduces the overhead significantly. A flexible and programmable platform based on Linux machines was chosen to allow the easy implementation and adaptation to different standards. This offers the possibility to apply the system not only to satellite communications, but provides seamless integration with terrestrial fixed broadcast wireless access systems. The platform is also an ideal test-bed for a variety of interactive broadband communications systems. The paper describes the system architecture and the key features of the system.

Koudelka, O.; Schmidt, M.; Ebert, J.; Schlemmer, H.; Kastner-Puschl, S.; Riedler, W.

2004-08-01

154

COVICS: A covert video communications system  

NASA Astrophysics Data System (ADS)

A covert video communications system compatible with narrow band satellite use has been developed. The system communications by modulating reflected energy. This means that no energy is actively generated at the passive end of the link. Only the antenna is impedance is modulated to return the information. The recovered signal is then coherently demodulated to recover the information. The system uses microstrip antennas, operates at 10 GHz, and has a range of about 5 km. The video is slow scan and is updated every 2 seconds, and can be sent over a 2400 baud line such as is required for some satellite communications systems. A combination of discrete cosine transform and video differencing was used to achieve a high degree of video compression.

Bracht, Roger; Kuckertz, Tom

155

Construction of a Communication Audit: An Examination of Communication Systems and Their Effectiveness.  

ERIC Educational Resources Information Center

Abstracts of 12 papers concerning the effectiveness of various communication systems are printed here. Subjects of the papers are: the appraisal of organizational communication systems, and evaluation of ECCO analysis as a communication audit methodology, assessment of attitude and opinion change effects of the communication audit, organizational…

Peterson, Brent D., Ed.; Greenbaum, Howard H., Ed.

156

Transmission of systemic AA amyloidosis in animals.  

PubMed

Amyloidoses are a group of protein-misfolding disorders that are characterized by the deposition of amyloid fibrils in organs and/or tissues. In reactive amyloid A (AA) amyloidosis, serum AA (SAA) protein forms deposits in mice, domestic and wild animals, and humans that experience chronic inflammation. AA amyloid fibrils are abnormal ?-sheet-rich forms of the serum precursor SAA, with conformational changes that promote fibril formation. Extracellular deposition of amyloid fibrils causes disease in affected animals. Recent findings suggest that AA amyloidosis could be transmissible. Similar to the pathogenesis of transmissible prion diseases, amyloid fibrils induce a seeding-nucleation process that may lead to development of AA amyloidosis. We review studies of possible transmission in bovine, avian, mouse, and cheetah AA amyloidosis. PMID:24280941

Murakami, T; Ishiguro, N; Higuchi, K

2014-03-01

157

Differential phase shift keyed communication system  

NASA Technical Reports Server (NTRS)

A communication system using differential phase-shift-keying (DPSK) transmits and receives binary data without requiring timing or phase reference signals. The system encodes and modulates the data at the transmitter, and decodes and demodulates the data at the receiver, without ambiguity as to the data content.

Hopkins, P. M.; Wallingford, W. M. (inventors)

1974-01-01

158

Operational Availability of Railway Dispatch Communication System  

Microsoft Academic Search

In the article, issues on assessment of operational availability of transport telematic systems are presented. Digital railway dispatch communication system has been selected for analysis and assessment. Presented has been the model of the systempsilas exploitation process, including its functional structure. Markov and semi-Markov processes have been used for modelling of the exploitation process. The conclusion contains the example of

M. Siergiejczyk

2009-01-01

159

Progress of coherent optical fibre communication systems  

Microsoft Academic Search

The recent progress of coherent optical fibre communication systems is reviewed. System constituent technologies, such as coherent optical modulation-demodulation, optical direct amplification for repeaters and single polarization fibre transmission are outlined. Several important optical device technologies, such as frequency stabilization of semiconductor lasers, AM and FM quantum noise and their reduction, and integrated opto-electronic devices, are also described. Finally, on

Tatsuya Kimura; Yoshihisa Yamamoto

1983-01-01

160

Smart antennas for wireless communications systems  

Microsoft Academic Search

The fundamental idea behind smart antennas is to improve the performance of the wireless communication system by increasing the gain in a chosen direction. This can be achieved by pointing the main lobes of the antenna-beam patterns towards the desired users. Smart antenna system combines multiple antenna elements with a signal processing capability to automatically optimise its radiation and\\/or reception

Ioan Nicolaescu; Dan Stoica

2010-01-01

161

State Restoration in Systems of Communicating Processes  

Microsoft Academic Search

In systems of asynchronous processes using messagelists with SEND–RECEIVE primitives for interprocess communication recovery primitives are defined to perform state restoration: MARK saves a particular point in the execution of the program; RESTORE resets the system state to an earlier point (saved by MARK); and PURGE discards redundant information when it is no longer needed for possible state restoration.

David L. Russell

1980-01-01

162

Radiation-hardened microwave communications system  

Microsoft Academic Search

To develop a wireless communication system to meet the stringent requirements for a nuclear hot cell and similar environments, including control of advanced servomanipulators, a microwave signal transmission system development program was established to produce a demonstration prototype for the Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory (ORNL). Proof-of-principle tests in a partially metal lined enclosure at ORNL

S. F. Smith; D. W. Bible; R. I. Crutcher; J. H. Hannah; J. A. Moore; C. H. Nowlin; R. I. Vandermolen; D. Chagnot; A. Leroy

1993-01-01

163

Dual Receiver Communication System for DSRC  

Microsoft Academic Search

This is the first study and field test analysis for DSRC (Dedicated Short distance Radio System) Vehicle wireless communication system design with first prototype developed WAVE (Wireless Access in Vehicle Environment) system platform in which IEEE802.11p and IEEE1609 standard software have been implemented. In the field test, packet reach ability as one of parameter for system evaluation has been measured

Tsutomu Tsuboi; Jun Yamada; Naoki Yamauchi; Masato Hayashi

2008-01-01

164

Communication Capacity Optimization for Broadband Satellite Communication Systems  

NASA Astrophysics Data System (ADS)

ground-based access systems, such as FTTH, ADSL and even terrestrial cellular systems, are only available within limited geographical areas, broadband satellite communication systems that can cover unlimited service area have attracted wide interest. However, the success of broadband satellite communication depends heavily on the cost of user terminals and satellite circuits. and frequency bandwidth, which involves design parameters. For such parameters, we must consider modulation, coding, the number of radiating beams and the number of areas in which frequency bandwidth can be reused. These parameters should be chosen such that maximum communication capacity can be provided with minimum system resources under a designated rain attenuation and interference environment. The difficulty in optimization stems from the number of design parameters and the interactions between them. The optimization also has to be done in a manner such that the service provider can determine the relation between the service cost and the service grade. The service grade can be expressed in terms of the available user information rate, return link as well as forward link, and the number of available communication channels, while the system cost can be expressed in terms of required satellite power and the bandwidth. power and bandwidth parameters. In the method, the number of spot beams, the number of repeated bandwidth areas and the type of modulation are separately determined for the return and forward link. From the selected design parameters, the relationship between bandwidth capacity and power capacity is derived assuming they are linear. The power and bandwidth required for the return and forward link are then integrated by applying a linear programming method. The constraints in linear programming are power and bandwidth. To denote the system resource management proficiency, we introduce an index called power-utilization efficiency, which is a ratio of the maximum capacity to the required power. systems that have 15 or 35 spot beams. Since circuit quality degradation in Ku band systems due to the propagation environments is less than that in Ka band systems, the power-utilization efficiency of the Ku band is 1.25 times more that of the Ka band. On the other hand, the total capacity of the Ka band is 3.5 times that of the Ku band since the allocated bandwidth in the Ku band is narrower than that of the Ka band. Bandwidth reuse is an effective way to increase total available bandwidth. For the same service area and the same number of reused bandwidths, increasing the number of spot beams can reduce the interference between different areas assigned the same frequency, since the distance between those areas widens. This enables total capacity and power-utilization efficiency for a 35-spot-beam system to be more than 2.2 and 2.75 times greater, respectively, than for a 15-spot-beam system. limited transmission power of the user terminal. Therefore, the return link transponder requires a higher transmission power level to compensate for this limitation. On the other hand, a high-quality downlink is also required for the forward link because of the small size of the user terminal antenna. However, the quality of the forward link can be maintained since it is possible to increase uplink quality by improving hub-station performance. This makes it possible to suppress the increase in the transmission power of the forward link transponder in comparison with that of the return link transponder. As an example, we compared two cases, in one of which the capacity ratio (forward link capacity divided by the return link capacity) was 2.0 and in the other of which it was 10.0. We found that the amount of capacity and power utilization efficiency were, respectively, 33% and 50% greater for the latter case than for the former case. applications.

Nakasuga, Yoshinori; Mitsugi, Jin; Ueba, Masazumi; Mizuno, Hideki

2002-01-01

165

Modeling and evaluation of aerial layer communications system architectures  

E-print Network

Airborne networks are being developed to provide communications services in order to augment space-based and terrestrial communications systems. These airborne networks must provide point to point wireless communications ...

Ajemian, Stephen P

2014-01-01

166

Animations  

NSDL National Science Digital Library

This collection contains animations of a nuclear chain reaction, nuclear fission and nuclear fusion. It also showcases interactive models of the first atomic bombs and simulation of the "Nuclear Winter" effect.

Christopher Griffith

167

Competitive field testing of moored buoy communications systems  

Microsoft Academic Search

Communications are crucial to ocean observing systems. The Gulf of Maine Ocean Observing System (GOMOOS) relies on an analog cell phone or Iridium satellite phone for primary communications, and a GOES satellite transmitter for backup. New communication technology has evolved since the design of the GOMOOS system which pushes the envelope of buoy communications. With the anticipated phase out of

R. Stessel; P. Fikes

2005-01-01

168

Degree project in Communication Systems  

E-print Network

, Sweden 30 of June 2013 #12;#12;i Abstract Currently, Android is the most popular operating system on devices that use Android operating system. Moreover, it provides ways of decreasing overall test execution;#12;iii Sammanfattning För närvarande är Android det mest populära operativ system för mobila enheter, men

Maguire Jr., Gerald Q.

169

Communication Theory of Secrecy Systems?  

Microsoft Academic Search

detailed study is made of the many standard types of codes and ciphers, and of the ways of breaking them. We will be more concerned with the general mathematical structure and properties of secrecy systems. The treatment is limited in certain ways. First, there are three general types of secrecy system: (1) concealment systems, including such methods as invisible ink,

C. E. SHANNON

170

Static and Animated Presentations in Learning Dynamic Mechanical Systems  

ERIC Educational Resources Information Center

In two experiments, we investigated how learners comprehend the functioning of a three-pulley system from a presentation on a computer screen. In the first experiment (N = 62) we tested the effect of static vs. animated presentations on comprehension. In the second experiment (N = 45), we tested the effect of user-control of an animated

Boucheix, Jean-Michel; Schneider, Emmanuel

2009-01-01

171

A small terminal for satellite communication systems  

NASA Technical Reports Server (NTRS)

A small portable, low-cost satellite communications terminal system incorporating a modulator/demodulator and convolutional-Viterbi coder/decoder is described. Advances in signal processing and error-correction techniques in combination with higher power and higher frequencies aboard satellites allow for more efficient use of the space segment. This makes it possible to design small economical earth stations. The Advanced Communications Technology Satellite (ACTS) was chosen to test the system. ACTS, operating at the Ka band incorporates higher power, higher frequency, frequency and spatial reuse using spot beams and polarization.

Xiong, Fuqin; Wu, Dong; Jin, Min

1994-01-01

172

How to bootstrap a human communication system.  

PubMed

How might a human communication system be bootstrapped in the absence of conventional language? We argue that motivated signs play an important role (i.e., signs that are linked to meaning by structural resemblance or by natural association). An experimental study is then reported in which participants try to communicate a range of pre-specified items to a partner using repeated non-linguistic vocalization, repeated gesture, or repeated non-linguistic vocalization plus gesture (but without using their existing language system). Gesture proved more effective (measured by communication success) and more efficient (measured by the time taken to communicate) than non-linguistic vocalization across a range of item categories (emotion, object, and action). Combining gesture and vocalization did not improve performance beyond gesture alone. We experimentally demonstrate that gesture is a more effective means of bootstrapping a human communication system. We argue that gesture outperforms non-linguistic vocalization because it lends itself more naturally to the production of motivated signs. PMID:23763661

Fay, Nicolas; Arbib, Michael; Garrod, Simon

2013-01-01

173

Evolution of a radio communication relay system  

NASA Astrophysics Data System (ADS)

Providing long-distance non-line-of-sight control for unmanned ground robots has long been recognized as a problem, considering the nature of the required high-bandwidth radio links. In the early 2000s, the DARPA Mobile Autonomous Robot Software (MARS) program funded the Space and Naval Warfare Systems Center (SSC) Pacific to demonstrate a capability for autonomous mobile communication relaying on a number of Pioneer laboratory robots. This effort also resulted in the development of ad hoc networking radios and software that were later leveraged in the development of a more practical and logistically simpler system, the Automatically Deployed Communication Relays (ADCR). Funded by the Joint Ground Robotics Enterprise and internally by SSC Pacific, several generations of ADCR systems introduced increasingly more capable hardware and software for automatic maintenance of communication links through deployment of static relay nodes from mobile robots. This capability was finally tapped in 2010 to fulfill an urgent need from theater. 243 kits of ruggedized, robot-deployable communication relays were produced and sent to Afghanistan to extend the range of EOD and tactical ground robots in 2012. This paper provides a summary of the evolution of the radio relay technology at SSC Pacific, and then focuses on the latest two stages, the Manually-Deployed Communication Relays and the latest effort to automate the deployment of these ruggedized and fielded relay nodes.

Nguyen, Hoa G.; Pezeshkian, Narek; Hart, Abraham; Burmeister, Aaron; Holz, Kevin; Neff, Joseph; Roth, Leif

2013-05-01

174

Distributed Satellite Communication System Design: First-Order Interactions between System and Network  

E-print Network

Distributed Satellite Communication System Design: First-Order Interactions between System to bankruptcy. The upfront capital required to implement a satellite communications system is staggering and performance of a system. Traditionally, the first step toward designing satellite communication systems

de Weck, Olivier L.

175

Electronics systems test laboratory testing of shuttle communications systems  

NASA Technical Reports Server (NTRS)

Shuttle communications and tracking systems space to space and space to ground compatibility and performance evaluations are conducted in the NASA Johnson Space Center Electronics Systems Test Laboratory (ESTL). This evaluation is accomplished through systems verification/certification tests using orbiter communications hardware in conjunction with other shuttle communications and tracking external elements to evaluate end to end system compatibility and to verify/certify that overall system performance meets program requirements before manned flight usage. In this role, the ESTL serves as a multielement major ground test facility. The ESTL capability and program concept are discussed. The system test philosophy for the complex communications channels is described in terms of the major phases. Results of space to space and space to ground systems tests are presented. Several examples of the ESTL's unique capabilities to locate and help resolve potential problems are discussed in detail.

Stoker, C. J.; Bromley, L. K.

1985-01-01

176

Domestic satellite communications systems - Background and projections  

NASA Astrophysics Data System (ADS)

Planned and existing national and international communications satellites are reviewed, along with comparative costs for leasing or owning a satellite and the basic capabilities of communications spacecraft. Eleven different satellite communications systems existed in 1982, including Intelsat, Marisat/Inmarsat, and Intersputnik as the international segments, and the Molniya, Telesat, Palapa, Westar, Satcom, Comstar, Amersat, and the SBS national systems. Seven of the twenty countries leasing Intelsat services are planning their own satellites. Leasing permits full capabilities withno development costs and ensures the lessor of full use of the satellite capacities. Developing countries can then gain hands-on experience with space technologies. Future demands are discussed, noting the broadening of the available bandwidths, better orbit utilization, and increases in transponder numbers to handle increased loads in future spacecraft.

Bargellini, P. L.

177

Integrated Formation Optical Communication and Estimation System  

NASA Technical Reports Server (NTRS)

An architecture has been designed that integrates formation estimation methodologies, precision formation sensing, and high-bandwidth formation communication into a robust, strap-on system that meets knowledge and communication requirements for the majority of planned, precision formation missions. Specifically, the integrated system supports (a) sub-millimeter metrology, (b) multiple greater than 10 Mbps communication channels over a large, 10 deg field-of-view (FOV), and (c) generalized formation estimation methodologies. The sensing sub-system consists of several absolute, metrology gauges with up to 0.1 mm precision that use amplitude-modulated lasers and a LISA-heritage phase meter. Since amplitude modulation is used, inexpensive and robust diode lasers may be used instead of complex, frequency-stabilized lasers such as for nanometer-level metrology. The metrology subsystem laser transceivers consist of a laser diode, collecting optics, and an avalanche photo diode (APD) for detecting incoming laser signals. The APD is necessary since received power is small due to the large (for optical applications) FOV. The phase meter determines the phase of the incoming amplitude modulations as measured by the APD. This phase is equivalent to time-of-flight and, therefore, distance. By placing three laser transceivers on each spacecraft, 18 clock-offset-corrupted distances are calculated. These measurements are communicated and averaged to obtain nine correct distances between the transceivers. From these correct distances, the range and bearing between spacecraft and their relative attitude are determined. Next, communication is integrated on the laser carrier through spectral separation. Metrology amplitude modulations are limited to the 45-50 MHz band, leaving 0-45 MHz for communication. Through careful design of coding scheme, error correction, and filters, six independent 10 Mbps receive channels are possible. Hence, a spacecraft can simultaneously broadcast at 10 Mbps and listen to six other spacecraft. The integrated sensing and communication architecture has been developed, as have formation estimation methodologies that allow the sensing topology to reconfigure as spacecraft maneuver. A bench-top implementation of the integrated sensing and communication architecture is in progress. The final, multiple sensing/communication systems will be tied together via formation estimation algorithms that are also undergoing further development.

Scharf, Daniel; Kuhnert, Andreas; Kovalik, Joseph; Hadaegh, Fred; Shaddock, Daniel

2008-01-01

178

Therapeutic Ultrasound to Non-Invasively Create Intra-Cardiac Communications in an Intact Animal Model  

PubMed Central

Objective To determine if pulsed cavitational ultrasound therapy (histotripsy) can accurately and safely generate ventricular septal defects (VSDs) through the intact chest of a neonatal animal, with the eventual goal of developing a non-invasive technique of creating intra-cardiac communications in patients with congenital heart disease. Background Histotripsy is an innovative ultrasonic technique that generates demarcated, mechanical tissue fractionation utilizing high intensity ultrasound pulses. Previous work has shown that histotripsy can create atrial septal defects in a beating heart in an open-chest canine model. Methods Nine neonatal pigs were treated with transcutaneous histotripsy targeting the ventricular septum. Ultrasound pulses of 5?s duration at a peak negative pressure of 13 MPa and a pulse repetition frequency of 1 kHz were generated by a 1 MHz focused transducer. The procedure was guided by real-time ultrasound imaging. Results VSDs were created in all pigs with diameters ranging from 2–6.5mm. Six pigs were euthanized within 2 hrs of treatment, while 3 were recovered and maintained for 2–3 days to evaluate lesion maturation and clinical side effects. There were only transient clinical effects and pathology revealed mild collateral damage around the VSD with no significant damage to other cardiac or extra-cardiac structures. Conclusions Histotripsy can accurately and safely generate VSDs through the intact chest in a neonatal animal model. These results suggest that with further advances, histotripsy can be a useful, non-invasive technique to create intra-cardiac communications, which currently require invasive catheter-based or surgical procedures, to clinically stabilize newborn infants with complex congenital heart disease. PMID:20853366

Owens, Gabe E.; Miller, Ryan M.; Ensing, Greg; Ives, Kimberly; Gordon, David; Ludomirsky, Achi; Xu, Zhen

2010-01-01

179

46 CFR 121.602 - Internal communications systems.  

Code of Federal Regulations, 2014 CFR

...THAN 49 PASSENGERS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 121.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2014-10-01

180

46 CFR 121.602 - Internal communications systems.  

Code of Federal Regulations, 2012 CFR

...THAN 49 PASSENGERS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 121.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2012-10-01

181

46 CFR 184.602 - Internal communications systems.  

Code of Federal Regulations, 2013 CFR

...100 GROSS TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 184.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2013-10-01

182

46 CFR 121.602 - Internal communications systems.  

Code of Federal Regulations, 2013 CFR

...THAN 49 PASSENGERS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 121.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2013-10-01

183

46 CFR 184.602 - Internal communications systems.  

Code of Federal Regulations, 2011 CFR

...100 GROSS TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 184.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2011-10-01

184

46 CFR 184.602 - Internal communications systems.  

Code of Federal Regulations, 2012 CFR

...100 GROSS TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 184.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2012-10-01

185

46 CFR 121.602 - Internal communications systems.  

Code of Federal Regulations, 2011 CFR

...THAN 49 PASSENGERS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 121.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2011-10-01

186

46 CFR 184.602 - Internal communications systems.  

Code of Federal Regulations, 2014 CFR

...100 GROSS TONS) VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Control and Internal Communications Systems § 184.602 Internal communications systems...equipped with pilothouse control must have a fixed...

2014-10-01

187

Active Sensing by Unmanned Aircraft Systems in Realistic Communication  

E-print Network

Active Sensing by Unmanned Aircraft Systems in Realistic Communication Environments Eric W. Frew-theoretic framework for active sensing by unmanned aircraft systems in realistic communication environments of the active sensing framework. Keywords: active sensing, unmanned aircraft systems, stochastic approximation

Frew, Eric W.

188

47 CFR 90.465 - Control of systems of communication.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Control of systems of communication. 90.465...Transmitter Control § 90.465 Control of systems of communication. (a...station. In mobile-only systems, control may be exercised by the...

2013-10-01

189

A packet switched communications system for GRO  

NASA Technical Reports Server (NTRS)

This paper describes the packet switched Instrumenters Communication System (ICS) that was developed for the Command Management Facility at GSFC to support the Gamma Ray Observatory (GRO) spacecraft. The GRO ICS serves as a vital science data acquisition link to the GRO scientists to initiate commands for their spacecraft instruments. The system is ready to send and receive messages at any time, 24 hours a day and seven days a week. The system is based on X.25 and the International Standard Organization's (ISO) 7-layer Open Systems Interconnection (OSI) protocol model and has client and server components. The components of the GRO ICS are discussed along with how the Communications Subsystem for Interconnection (CSFI) and Network Control Program Packet Switching Interface (NPSI) software are used in the system.

Husain, Shabu; Yang, Wen-Hsing; Vadlamudi, Rani; Valenti, Joseph

1993-01-01

190

[Development of the lymphatic system in the animal kingdom].  

PubMed

This article gives a compact and simplified survey of the organization of the lymphatic vascular system or equivalent structures in animals resulting in the question how the phylogenetic evolution could have been. PMID:3739415

Zöltzer, H

1986-06-01

191

Learning Communication Strategies in Multiagent Systems  

Microsoft Academic Search

In this paper we describe a dynamic, adaptive communication strategy for multiagent systems. We discuss the behavioral parameters of each agent that need to be computed, and provide a quantitative solution to the problem of controlling these parameters. We also describe the testbed we built and the experiments we performed to evaluate the effectiveness of our methodology. Several experiments using

Michael Kinney; Costas Tsatsoulis

1998-01-01

192

A Multimodal 3D Healthcare Communication System  

Microsoft Academic Search

We present a system that integrates gesture recognition and 3D talking head technologies for a patient communication application at a hospital or healthcare setting for supporting patients treated in bed. As a multimodal user interface, we get the input from patients using hand gestures and provide feedback by using a 3D talking avatar.

Cem Keskin; Koray Balci; Oya Aran; Bülent Sankur; Lale Akarun

2007-01-01

193

Proceedings of the Military Communications System Control Symposium  

NASA Astrophysics Data System (ADS)

Contents: Perspective on Communications System Control, Navy Force Coordination and the Requirements for Communications Network Management, On the Functions of a Network Management Agency, Improved Control and Technical Management of DCS Theater Assets Under Crisis and Wartime Conditions, Survivability Performance of MX Communication System, System Control for the Tactical/Strategic Interface, Tactical Circuit-Switched Network Control, Systems Control in Tactical Digital Communications Systems - a Study in Distributed Control, the NATO III Satellite Communications Control System, Network Control in NATO Integrated Communications Systems - Stage I, Evolution of Control in the Defense Satellite Communication System, System Control Considerations for Next Generation DCS Switches, Evolving Approaches to System control in the Defense Communications Systems(DCS), and Network control and the CRM Make Possible Automated Digital Patching.

Harris, S.; Heller, J.

1980-11-01

194

DCS/FTS Commercial Satellite Communications System  

NASA Astrophysics Data System (ADS)

In order to control the rising costs of telephonic services and meeting the increasing demand for wideband video and data services within U.S. Federal Government agencies, the Defense Communications Agency and the General Services Administration have begun the implementation of a leased Commercial Satellite Communications System. Service volume demand, commonality of service requirements, and common geographic communities of interest facilitate economies of scale in the course of meeting DOD and other Federal agencies' objectives. The service, which incorporates the Federal Telecommunications Service and is therefore designated DCS/FTS, is presently studied with respect to military and national objectives.

Shimabukuro, T.; Rosner, R.; Pearsall, C.

195

Aircraft communication via telefacsimile system  

NASA Technical Reports Server (NTRS)

Based on reading rate of between 500-1000 words/minute, transmitting typewritten matter only, system uses lowest possible bandwidth to avoid overcrowding, while furnishing data as fast as it can be absorbed by pilot. Bandwidth requirements are less than 150 kHz, a considerable saving over conventional television.

Brown, R. L., Sr.

1972-01-01

196

Tri-modality small animal imaging system  

SciTech Connect

Our group is developing a scanner that combines x-ray, single gamma, and optical imaging on the same rotating gantry. Two functional modalities (SPECT and optical) are included because they have different strengths and weaknesses in terms of spatial and temporal decay lengths in the context of in vivo imaging, and because of the recent advent of multiple reporter gene constructs. The effect of attenuation by biological tissue on the detected intensity of the emitted signal was measured for both gamma and optical imaging. Attenuation by biological tissue was quantified for both the bioluminescent emission of luciferace and for the emission light of the near infrared fluorophore cyanine 5.5, using a fixed excitation light intensity. Experiments were performed to test the feasibility of using either single gamma or x-ray imaging to make depth-dependent corrections to the measured optical signal. Our results suggest that significant improvements in quantitation of optical emission are possible using straightforward correction techniques based on information from other modalities. Development of an integrated scanner in which data from each modality are obtained with the animal in a common configuration will greatly simplify this process.

Kundu, B.K.; Stolin, A.V.; Pole, J.; Baumgart, L.; Fontaine, M.; Wojcik, R.; Kross, B.; Zorn, C.; Majewski, S.; Williams, M.B.

2006-02-01

197

Energy efficiency in wireless communication systems  

DOEpatents

Wireless communication systems and methods utilize one or more remote terminals, one or more base terminals, and a communication channel between the remote terminal(s) and base terminal(s). The remote terminal applies a direct sequence spreading code to a data signal at a spreading factor to provide a direct sequence spread spectrum (DSSS) signal. The DSSS signal is transmitted over the communication channel to the base terminal which can be configured to despread the received DSSS signal by a spreading factor matching the spreading factor utilized to spread the data signal. The remote terminal and base terminal can dynamically vary the matching spreading factors to adjust the data rate based on an estimation of operating quality over time between the remote terminal and base terminal such that the amount of data being transmitted is substantially maximized while providing a specified quality of service.

Caffrey, Michael Paul; Palmer, Joseph McRae

2012-12-11

198

Land-mobile satellite communication system  

NASA Technical Reports Server (NTRS)

A satellite communications system includes an orbiting communications satellite for relaying communications to and from a plurality of ground stations, and a network management center for making connections via the satellite between the ground stations in response to connection requests received via the satellite from the ground stations, the network management center being configured to provide both open-end service and closed-end service. The network management center of one embodiment is configured to provides both types of service according to a predefined channel access protocol that enables the ground stations to request the type of service desired. The channel access protocol may be configured to adaptively allocate channels to open-end service and closed-end service according to changes in the traffic pattern and include a free-access tree algorithm that coordinates collision resolution among the ground stations.

Yan, Tsun-Yee (Inventor); Rafferty, William (Inventor); Dessouky, Khaled I. (Inventor); Wang, Charles C. (Inventor); Cheng, Unjeng (Inventor)

1993-01-01

199

Degree project in Communication Systems  

E-print Network

A R A D O G A N Evaluating WebSocket and WebRTC in the Context of a Mobile Internet of Things Gateway of a Mobile Internet of Things Gateway Gunay Mert Karadogan Master of Science Thesis Embedded Systems School to the Internet in order to foster an Internet of Things (IoT). This thesis project aims to solve the problem

Maguire Jr., Gerald Q.

200

A passive integrated transponder system for tracking animal movements  

USGS Publications Warehouse

We describe an automated system that uses passive integrated transponder (PIT) tags to track movements of animals past specific locations. The system was designed to operate maintenance free for several months, be secure from vandalism and environmental damage, and record the identity, date, and time of passage of animals past a 2.4-m wide area. We used the system to monitor effectively the movements of 172 desert tortoises (Gopherus agassizii) through 2 storm drain culverts that pass beneath a state highway in the Mojave Desert, California. Four tortoises entered or passed through the culverts on 60 occasions. The system can be easily adapted to other species.

Boarman, W.I.; Beigel, M.L.; Goodlett, G.C.; Sazaki, M.

1999-01-01

201

Parallel processing spacecraft communication system  

NASA Technical Reports Server (NTRS)

An uplink controlling assembly speeds data processing using a special parallel codeblock technique. A correct start sequence initiates processing of a frame. Two possible start sequences can be used; and the one which is used determines whether data polarity is inverted or non-inverted. Processing continues until uncorrectable errors are found. The frame ends by intentionally sending a block with an uncorrectable error. Each of the codeblocks in the frame has a channel ID. Each channel ID can be separately processed in parallel. This obviates the problem of waiting for error correction processing. If that channel number is zero, however, it indicates that the frame of data represents a critical command only. That data is handled in a special way, independent of the software. Otherwise, the processed data further handled using special double buffering techniques to avoid problems from overrun. When overrun does occur, the system takes action to lose only the oldest data.

Bolotin, Gary S. (Inventor); Donaldson, James A. (Inventor); Luong, Huy H. (Inventor); Wood, Steven H. (Inventor)

1998-01-01

202

Communications and control for electric power systems  

NASA Technical Reports Server (NTRS)

The first section of the report describes the AbNET system, a hardware and software communications system designed for distribution automation (it can also find application in substation monitoring and control). The topology of the power system fixes the topology of the communications network, which can therefore be expected to include a larger number of branch points, tap points, and interconnections. These features make this communications network unlike any other. The network operating software has to solve the problem of communicating to all the nodes of a very complex network in as reliable a way as possible even if the network is damaged, and it has to do so with minimum transmission delays and at minimum cost. The design of the operating protocols is described within the framework of the seven-layer Open System Interconnection hierarchy of the International Standards Organization. Section 2 of the report describes the development and testing of a high voltage sensor based on an electro-optic polymer. The theory of operation is reviewed. Bulk fabrication of the polymer is discussed, as well as results of testing of the electro-optic coefficient of the material. Fabrication of a complete prototype sensor suitable for use in the range 1-20 kV is described. The electro-optic polymer is shown to be an important material for fiber optic sensing applications. Appendix A is theoretical support for this work. The third section of the report presents the application of an artificial neural network, Kohonen's self-organizing feature map, for the classification of power system states. This classifier maps vectors of an N-dimensional space to a 2-dimensional neural net in a nonlinear way preserving the topological order of the input vectors. These mappings are studied using a nonlinear power system model.

Kirkham, H.; Goettsche, A.; Niebur, D.; Friend, H.; Johnston, A.

1991-01-01

203

30 CFR 57.18013 - Emergency communications system.  

Code of Federal Regulations, 2011 CFR

... false Emergency communications system. 57.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND...18013 Emergency communications system. A...

2011-07-01

204

30 CFR 57.18013 - Emergency communications system.  

Code of Federal Regulations, 2014 CFR

... false Emergency communications system. 57.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND...18013 Emergency communications system. A...

2014-07-01

205

30 CFR 56.18013 - Emergency communications system.  

Code of Federal Regulations, 2010 CFR

... false Emergency communications system. 56.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE...18013 Emergency communications system. A...

2010-07-01

206

30 CFR 56.18013 - Emergency communications system.  

Code of Federal Regulations, 2012 CFR

... false Emergency communications system. 56.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE...18013 Emergency communications system. A...

2012-07-01

207

30 CFR 57.18013 - Emergency communications system.  

Code of Federal Regulations, 2010 CFR

... false Emergency communications system. 57.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND...18013 Emergency communications system. A...

2010-07-01

208

30 CFR 56.18013 - Emergency communications system.  

Code of Federal Regulations, 2011 CFR

... false Emergency communications system. 56.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE...18013 Emergency communications system. A...

2011-07-01

209

30 CFR 57.18013 - Emergency communications system.  

Code of Federal Regulations, 2013 CFR

... false Emergency communications system. 57.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND...18013 Emergency communications system. A...

2013-07-01

210

30 CFR 56.18013 - Emergency communications system.  

Code of Federal Regulations, 2014 CFR

... false Emergency communications system. 56.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE...18013 Emergency communications system. A...

2014-07-01

211

30 CFR 57.18013 - Emergency communications system.  

Code of Federal Regulations, 2012 CFR

... false Emergency communications system. 57.18013... MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT...NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND...18013 Emergency communications system. A...

2012-07-01

212

Cooperative diversity versus antenna diversity in wireless communication systems  

Microsoft Academic Search

Cooperative communication, a new way of communication has found its applications in almost every wireless network, from cellular to adhoc and sensor networks. The basic idea of cooperative communication is to emulate virtual antenna array to mimic a multi antenna system and hence get improved performance. In this paper, we provide performance analysis of cooperative communication using two basic cooperative

M. Abrar; X. Gui; A. Punchihewa; S. Khan; M. Iqbal

2010-01-01

213

Orbiter Interface Unit and Early Communication System  

NASA Technical Reports Server (NTRS)

This report describes the Orbiter Interface Unit (OIU) and the Early Communication System (ECOMM), which are systems of electronic hardware and software that serve as the primary communication links for the International Space Station (ISS). When a space shuttle is at or near the ISS during assembly and resupply missions, the OIU sends groundor crew-initiated commands from the space shuttle to the ISS and relays telemetry from the ISS to the space shuttle s payload data systems. The shuttle then forwards the telemetry to the ground. In the absence of a space shuttle, the ECOMM handles communications between the ISS and Johnson Space Center via the Tracking and Data Relay Satellite System (TDRSS). Innovative features described in the report include (1) a "smart data-buffering algorithm that helps to preserve synchronization (and thereby minimize loss) of telemetric data between the OIU and the space-shuttle payload data interleaver; (2) an ECOMM antenna-autotracking algorithm that selects whichever of two phased-array antennas gives the best TDRSS signal and electronically steers that antenna to track the TDRSS source; and (3) an ECOMM radiation-latchup controller, which detects an abrupt increase in current indicative of radiation-induced latchup and temporarily turns off power to clear the latchup, restoring power after the charge dissipates.

Cobbs, Ronald M.; Cooke, Michael P.; Cox, Gary L.; Ellenberger, Richard; Fink, Patrick W.; Haynes, Dena S.; Hyams, Buddy; Ling, Robert Y.; Neighbors, Helen M.; Phan, Chau T.; Prendergast, Kelly M.; Siekierski, James D.; Wade, Randall S.; Weisskopf, George A.; Yim, Hester J.; Adkins, Antha A.; Carl, James R..; Loh, Y. C.; Roberts, Charles; Steele, Douglas J.; DeSilva, Buveneka Kanishka; Killenb, Harold B.; Williams, Robert M.

2004-01-01

214

Integrated communications and optical navigation system  

NASA Astrophysics Data System (ADS)

The Integrated Communications and Optical Navigation System (ICONS) is a flexible navigation system for spacecraft that does not require global positioning system (GPS) measurements. The navigation solution is computed using an Unscented Kalman Filter (UKF) that can accept any combination of range, range-rate, planet chord width, landmark, and angle measurements using any celestial object. Both absolute and relative orbit determination is supported. The UKF employs a full nonlinear dynamical model of the orbit including gravity models and disturbance models. The ICONS package also includes attitude determination algorithms using the UKF algorithm with the Inertial Measurement Unit (IMU). The IMU is used as the dynamical base for the attitude determination algorithms. This makes the sensor a more capable plug-in replacement for a star tracker, thus reducing the integration and test cost of adding this sensor to a spacecraft. Recent additions include an integrated optical communications system which adds communications, and integrated range and range rate measurement and timing. The paper includes test results from trajectories based on the NASA New Horizons spacecraft.

Mueller, J.; Pajer, G.; Paluszek, M.

2013-12-01

215

Relay Communication with Delay Diversity for Future Communication Systems  

Microsoft Academic Search

In this paper we consider relay communication as a way of increasing the diversity gain in fading wireless environments. The idea is to combine relay communication with delay diversity where each relay introduces a certain time delay to the signal before forwarding. The result is an increased frequency selectivity in the relay channel which can be exploited at the receiver.

S. Ben Slimane; Afif Osseiran

2006-01-01

216

A smart system for surveillance of animal welfare during transport.  

PubMed

New welfare regulations will impose surveillance systems so that information on the quality of transport conditions is available. Moreover a route description is useful for optimisation of transport logistics, but also in relation to estimating of sanitary risk and food safety, including traceability of individual animals. Therefore a transport surveillance system has been developed which is integrating the following information: individual identification of animals, (un)loading place and time, air quality (temperature, relative humidity, emissions), vibration and behaviour of the animals. These data are collected by telemetry and GPS, and are transmitted to a dispatch centre by GSM. Hence, information is available on-line and on disk, so that the driver can be informed and corrected at the spot. Dynamic route optimization of cattle collection from farms and logistical activities of abattoirs are considered in relation to animal welfare. Another instrumentation package that comprises sensors of heart rate and vibration on the animal has been integrated. These sensors can be mounted on animals and the data is transferred to a database through a wireless network. Comprehensive field measurement has been made to evaluate the system and found that the package performs well. Hence, advice will be generated for vehicle manufacturers, hauliers, farmers, slaughterhouses and retailers. PMID:14746056

Gebresenbet, G; Wikner, I; Van de Water, G; Freson, L; Geers, R

2003-12-01

217

Radio propagation for space communications systems  

NASA Technical Reports Server (NTRS)

This paper presents a review of the most recent information on the effects of the earth's atmosphere on space communications systems. Models and techniques used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission are discussed. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz are reviewed. Particular emphasis is placed on the effects of precipitation on the earth-space path, including rain attenuation, and rain and ice-particle depolarization. Sky noise, antenna gain degradation, scintillations, and bandwidth coherence are also discussed. The impact of the various propagation factors on communications system design criteria is presented. These criteria include link reliability, power margins, noise contributions, modulation and polarization factors, channel crosstalk, error-rate, and bandwidth limitations.

Ippolito, L. J.

1981-01-01

218

Issues in satellite personal communication systems  

Microsoft Academic Search

In the paper various issues in personal satellite communications are addressed. Basic geostationary and non?geostationary\\u000a satellite constellations are considered. The narrowband and wideband characterization of the mobile satellite channel and\\u000a related system implications are discussed. Satellite diversity is presented as a measure to overcome signal shadowing. The\\u000a capacity of TDMA and CDMA multiple access is estimated, taking into account co?channel

Erich Lutz

1998-01-01

219

A Time Domain Fluorescence Tomography System for Small Animal Imaging  

Microsoft Academic Search

We describe the application of a time domain diffuse fluorescence tomography system for whole body small animal imaging. The key features of the system are the use of point exci- tation in free space using ultrashort laser pulses and noncontact detection using a gated, intensified charge-coupled device (CCD) camera. Mouse shaped epoxy phantoms, with embedded fluores- cent inclusions, were used

Anand T. N. Kumar; Scott B. Raymond; Andrew K. Dunn; Brian J. Bacskai; David A. Boas

2008-01-01

220

Satellite communications systems move into the twenty-first century  

Microsoft Academic Search

This paper discusses the evolution of communication satellite systems and communications satellite technology from the 1960's\\u000a to the 1990's. The paper identifies the key attributes of satellite communications that has driven this evolution and now\\u000a drives the future directions such systems will take. The paper then discusses the future direction of communication satellite\\u000a systems including DBS, MSS, FSS and hybrid

Leonard S. Golding

1998-01-01

221

Integrated Energy and Communications System Architecture  

NSDL National Science Digital Library

A consortium of the Electricity Innovation Institute is developing an "an open, standards-based systems architecture for the data communications and distributed computing infrastructure that will enable the integration of a wide variety of intelligent electric power system components." Citing the overloaded U.S. power grid and changing trends in electricity demand, the consortium is advocating new technologies such as a self-healing grid and advanced monitoring capabilities. This Web site outlines the scope of the project and the motivation for conducting the work. Additionally, a white paper is provided that discusses the finer technical and implementation details of the proposed changes.

222

Satellite communications systems and technology. Executive Summary  

NASA Technical Reports Server (NTRS)

NASA and the National Science Foundation (NSF) commissioned a panel of US experts to study the international status of satellite communications systems and technology. The study covers emerging systems concepts, applications, services, and the attendant technologies. The panel members travelled to Europe, Japan, and Russia to gather information first-hand. They visited 17 sites in Europe, 20 sites in Japan, and four in Russia. These included major manufacturers, government organizations, service providers, and associated R&D facilities. The panel's report was reviewed by the sites visited, by the panel, and by representatives of US industry. The report details the information collected and compares it to US activities.

Edelson, Burton I.; Pelton, Joseph N.; Bostian, Charles W.; Brandon, William T.; Chan, Vincent W. S.; Hager, E. Paul; Helm, Neil R.; Jennings, Raymond D.; Kwan, Robert; Mahle, Christoph E.

1993-01-01

223

Influence of Interference in MIMO Power Line Communication systems  

E-print Network

1 Influence of Interference in MIMO Power Line Communication systems Thanh Nhan VO1, Karine AMIS1 the data rate in the next generation of power line communications. The HomePlug AV2 and ITU-T G.9963 to the interference is shown. Index Terms--MIMO, Power Line Communication, Interfer- ence, Modeling, System

Brest, Université de

224

Emergency Communication for Electric Power System Based on Airship  

Microsoft Academic Search

The problems facing the communication for electric power system safety were recently highlighted by ice disaster in southern China and Wenchuan earthquake. The existing communication systems in the Yunnan power grid are far from adequate. Terrestrial networks are disabled by serious natural disaster. Satellite communication network is deficient in bandwidth, and has high propagation delay, which cannot satisfy the demand

Ming Huang; Jiang Yu; Jinsong Hu; Ling Zhao; Rong Zong

2009-01-01

225

A Dispatch-Mediated Communication Model for Emergency Response Systems  

E-print Network

2 A Dispatch-Mediated Communication Model for Emergency Response Systems ROHIT VALECHA and RAJ of emergency communication is dispatch-mediated (the messages from the scene are directed towards, dispatch-mediated communication, emergency response systems ACM Reference Format: Valecha, R., Sharman, R

Upadhyaya, Shambhu

226

OPC UA for vertical communication in logistic informatics systems  

Microsoft Academic Search

Logistic systems play a crucial role in organization and management of every large enterprise. One very important issue is a vertical communication between localized on factory floor level data sources and business application level logistic systems. OPC UA allows for creating flexible and scalable vertical communication interface. Many interconnection problems related with communication between control and business level of IT

R. Cupek; A. Maka

2010-01-01

227

21 CFR 890.3710 - Powered communication system.  

Code of Federal Regulations, 2011 CFR

...communication methods because of physical impairment. Examples of powered communication systems include the following: a specialized typewriter, a reading machine, and a video picture and word screen. (b) Classification. Class II (special controls)....

2011-04-01

228

21 CFR 890.3710 - Powered communication system.  

Code of Federal Regulations, 2012 CFR

...communication methods because of physical impairment. Examples of powered communication systems include the following: a specialized typewriter, a reading machine, and a video picture and word screen. (b) Classification. Class II (special controls)....

2012-04-01

229

21 CFR 890.3710 - Powered communication system.  

Code of Federal Regulations, 2013 CFR

...communication methods because of physical impairment. Examples of powered communication systems include the following: a specialized typewriter, a reading machine, and a video picture and word screen. (b) Classification. Class II (special controls)....

2013-04-01

230

21 CFR 890.3710 - Powered communication system.  

Code of Federal Regulations, 2014 CFR

...communication methods because of physical impairment. Examples of powered communication systems include the following: a specialized typewriter, a reading machine, and a video picture and word screen. (b) Classification. Class II (special controls)....

2014-04-01

231

21 CFR 890.3710 - Powered communication system.  

Code of Federal Regulations, 2010 CFR

...communication methods because of physical impairment. Examples of powered communication systems include the following: a specialized typewriter, a reading machine, and a video picture and word screen. (b) Classification. Class II (special controls)....

2010-04-01

232

Communicating Research to Small Drinking Water Systems: Dissemination by Researchers  

EPA Science Inventory

This talk discusses the challenges of disseminating research relevant to small systems. The presentation discusses efforts by the U.S. EPA’s Office of Research and Development to effectively communicating drinking water information. In particular, communication approaches ...

233

Risk communication strategy development using the aerospace systems engineering process  

NASA Technical Reports Server (NTRS)

This paper explains the goals and challenges of NASA's risk communication efforts and how the Aerospace Systems Engineering Process (ASEP) was used to map the risk communication strategy used at the Jet Propulsion Laboratory to achieve these goals.

Dawson, S.; Sklar, M.

2004-01-01

234

Crew/computer communications study. Volume 1: Final report. [onboard computerized communications system for spacecrews  

NASA Technical Reports Server (NTRS)

Techniques, methods, and system requirements are reported for an onboard computerized communications system that provides on-line computing capability during manned space exploration. Communications between man and computer take place by sequential execution of each discrete step of a procedure, by interactive progression through a tree-type structure to initiate tasks or by interactive optimization of a task requiring man to furnish a set of parameters. Effective communication between astronaut and computer utilizes structured vocabulary techniques and a word recognition system.

Johannes, J. D.

1974-01-01

235

47 CFR 11.47 - Optional use of other communications methods and systems.  

Code of Federal Regulations, 2014 CFR

...Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EMERGENCY ALERT SYSTEM (EAS...Optional use of other communications methods and systems...Bureau or their State Emergency Communications Committee for...

2014-10-01

236

A comparative study of coagulation systems in newborn animals.  

PubMed

Appropriate animal experimentation can enhance our understanding of thrombotic and hemorrhagic problems in the human neonate. Which newborn animal species' coagulation system most closely resembles the human neonate is unknown. The objective of the study was to assess the newborn coagulation system in four animal species and compare them with the human neonate. Blood samples were drawn on days 1 and 7 of life from lambs (n = 10), piglets, (n = 12), rabbit pups (n = 12), and beagle pups (n = 7). Coagulation screening tests, specific factor assays, and specific inhibitors of the coagulation system were measured. All factor assays were expressed as a percent of the respective species pooled adult plasma. The results from the animals were compared to normal values from our laboratory for healthy full-term infants. The coagulation systems of all species tested, except the rabbit pup, were immature at birth with most factor levels being lower than the adult of their species. The coagulation systems were influenced by the postnatal age of the animal and the factor levels reached adult values in fewer days relative to the human. The coagulation system for the piglet most closely approximated the human neonate. The shared characteristics were prolonged screening tests, increased factor VIII:C, generally low levels for the contact and vitamin K-dependent factors, and low antithrombin III levels relative to the adult. The beagle pup also showed many similar characteristics but in contrast to the human neonate factor VIII:C and V were low on day 1 of life and prekallikrein was not measurable in the adult or newborn beagle.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3774411

Massicotte, P; Mitchell, L; Andrew, M

1986-10-01

237

A model of communications for anthropocentric cell manufacturing system  

Microsoft Academic Search

The anthropocentric cell manufacturing system (ACMS), using a basic concept of skill-based manufacturing and integration of automation system is proposed. Manufacturing systems generally require an appropriate communication system to manage and control ACMS resources. The model of ACMS communication system composes of management, manufacturing, and new OJT unit. The proposed model is initially constructed by an application of information technologies,

Bandit Suksawat; Hiraoka Hiroyuki; Ihara Tohru

2007-01-01

238

Antenna technology for advanced mobile communication systems  

NASA Technical Reports Server (NTRS)

The onboard antenna front end is the key subsystem conditioning configuration and performance of mobile communication satellites. The objectives of this paper are to demonstrate this key role and to review L-band satellite antenna technology for earth coverage and regional applications. Multibeam arrays are first discussed, then unfurlable and inflatable reflector antennas are described. These technologies are now qualified in Europe for future mobile systems, for which the optimum choice of antenna technology has been found to be the key to efficient use of spectrum and power resources.

Rammos, Emmanuel; Roederer, Antoine; Rogard, Roger

1988-01-01

239

GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM  

SciTech Connect

Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. A prototype system was built for low-pressure cast-iron mains and tested in a spider- and serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The prototype unit combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-slave architecture to collect data from a distributed spider-arrangement, and in a master-repeater-slave configuration in serial or ladder-network arrangements. It was found that the system was capable of performing all data-sampling and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and valuable data was collected in order to determine how to improve on range and data-quality in the future.

Hagen Schempf, Ph.D.

2003-02-27

240

An advanced domestic satellite communications system  

NASA Technical Reports Server (NTRS)

An updated traffic projection for U.S. domestic satellite communications service covering a period of 15 years; mid-1980 to mid-1995 was prepared. This model takes into account expected technology advances and reductions in transmission costs, legislative and regulatory changes permitting increased competition, and rising energy costs which will encourage more extensive substitution of telecommunications for travel. The historical development and current status of satellite systems are discussed as well as the characteristics of follow-on systems. Orbital arc utilization, spacecraft configuration for single shuttle launch, Earth station configuration, and system costs are examined. Areas which require technology development include multiple beam frequency reuse antennas, on-board switching, intersatellite links, and ka-band operation. Packing and deployment schemes for enclosing the satellite within the shuttle orbiter bay must also be devised.

1980-01-01

241

Multi-EVA communications system analysis  

NASA Technical Reports Server (NTRS)

A communications concept is analyzed to establish requirements of a confident candidate system for space shuttle. Conceptual baseline configurations, EVA's-to-spacecraft via PCM/FDM and spacecraft-to-EVA via PAM/FM, and respective functional performance requirements are discussed. The baseline system is analyzed to determine link characteristics, EMI levels at various frequency bands, and determination of desirable spectrum. Selected L- and S-Band links are analyzed to ascertain signal design parameters. A trade-off is performed, which establishes L-Band frequency as the best compromise. The results of the analysis along with the reliability/safety aspects and physical characteristics of the candidate system, indicate that the initial baseline concept meets functional requirements, but is poor from standpoint of overall space shuttle program cost.

1972-01-01

242

Animated phase portraits of nonlinear and chaotic dynamical systems  

E-print Network

The aim of this section is to present programs allowing to high- light the slow-fast evolution of the solutions of nonlinear and chaotic dynamical systems such as: Van der Pol, Chua and Lorenz models. These programs provide animated phase portraits in dimension two and three, i.e. integration step by step" which are useful tools enabling to understand the dynamic of such systems.

Jean-Marc Ginoux

2014-08-17

243

GAS MAIN SENSOR AND COMMUNICATIONS NETWORK SYSTEM  

SciTech Connect

Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. In Phase II of this three-phase program, an improved prototype system was built for low-pressure cast-iron and high-pressure steel (including a no-blow installation system) mains and tested in a serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The experiment was carried out in several open-hole excavations over a multi-day period. The prototype units (3 total) combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-repeater-slave configuration in serial or ladder-network arrangements. It was verified that the system was capable of performing all data-sampling, data-storage and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and the system was demonstrated to run off in-ground battery- and above-ground solar power. The remote datalogger access and storage-card features were demonstrated and used to log and post-process system data. Real-time data-display on an updated Phase-I GUI was used for in-field demonstration and troubleshooting.

Hagen Schempf

2004-09-30

244

Resolving current disagreements and ambiguities in the terminology of animal communication.  

PubMed

Communication is central to most interactions between organisms. There is currently considerable controversy about the evolution, function and even about the most basic definition of communication. The controversy is linked to definitional ambiguities and disagreements. Here we discuss how some recent disagreements can be resolved and offer a clear set of definitions. Central to our approach is a definition of communication as being a trade between one organism (the informer) and another (the perceiver). The informer exerts influence on the perceiver through the communication process, and the perceiver experiences a change in its informational state (that is, gains information) as a consequence of detecting the communication. We define both influence and information explicitly and delineate between signalling, deceptive communication, and situations where perceivers respond to cues rather than signals. We demonstrate how our definitions allow resolution of conflicts arising in recent publications on the definitions on communication and related terms. PMID:21902751

Ruxton, G D; Schaefer, H M

2011-12-01

245

The principle of the positioning system based on communication satellites  

Microsoft Academic Search

It is a long dream to realize the communication and navigation functionality in a satellite system in the world. This paper\\u000a introduces how to establish the system, a positioning system based on communication satellites called Chinese Area Positioning\\u000a System (CAPS). Instead of the typical navigation satellites, the communication satellites are configured firstly to transfer\\u000a navigation signals from ground stations, and

Guoxiang Ai; Huli Shi; Haitao Wu; Zhigang Li; Ji Guo

2009-01-01

246

Ultrasonic speech translator and communications system  

DOEpatents

A wireless communication system undetectable by radio frequency methods for converting audio signals, including human voice, to electronic signals in the ultrasonic frequency range, transmitting the ultrasonic signal by way of acoustical pressure waves across a carrier medium, including gases, liquids, or solids, and reconverting the ultrasonic acoustical pressure waves back to the original audio signal. The ultrasonic speech translator and communication system (20) includes an ultrasonic transmitting device (100) and an ultrasonic receiving device (200). The ultrasonic transmitting device (100) accepts as input (115) an audio signal such as human voice input from a microphone (114) or tape deck. The ultrasonic transmitting device (100) frequency modulates an ultrasonic carrier signal with the audio signal producing a frequency modulated ultrasonic carrier signal, which is transmitted via acoustical pressure waves across a carrier medium such as gases, liquids or solids. The ultrasonic receiving device (200) converts the frequency modulated ultrasonic acoustical pressure waves to a frequency modulated electronic signal, demodulates the audio signal from the ultrasonic carrier signal, and conditions the demodulated audio signal to reproduce the original audio signal at its output (250).

Akerman, M. Alfred (Knoxville, TN); Ayers, Curtis W. (Clinton, TN); Haynes, Howard D. (Knoxville, TN)

1996-01-01

247

A real-time photoacoustic tomography system for small animals  

PubMed Central

A real-time 512-element photoacoustic tomography system for small animal imaging using a ring ultrasound array has been developed. The system, based upon a 5 MHz transducer array formed along a 50 mm circular aperture, achieves sub-200 micron lateral resolution over a 2 cm disk-shaped region. Corresponding elevation resolutions of 0.6 to 2.5 mm over the central volume enable depth-resolved 3D tomographic imaging with linear translation. Using 8:1 electronic multiplexing, imaging at up to 8 frame/sec is demonstrated for both dynamic phantoms and in vivo mouse and brain samples. The real-time, full 2D tomographic capability of the system paves the way for functional photoacoustic tomographic imaging studies in small animals with sub-second time frame. PMID:19550444

Gamelin, John; Maurudis, Anastasios; Aguirre, Andres; Huang, Fei; Guo, Puyun; Wang, Lihong V.; Zhu, Quing

2009-01-01

248

Animal models for the mechanistic study of systemic lymphangiomatosis.  

PubMed

The systematic study of focused animal models has produced an explosion of information regarding the mechanisms governing lymphatic development and the diseases associated with lymphatic dysfunction. Nevertheless, the pathogenesis of systemic lymphangiomatosis has, thus far, eluded mechanistic comprehension. In this review, recent molecular advances in lymphatic vascular development are considered within the context of the animal models that have produced evolving insights. The emerging role of the zebrafish within lymphatic investigation is discussed. Specific models of the human disease pathology are considered in detail. While much has been learned about the molecular framework that surrounds normal lymphatic vascular development, the defect responsible for systemic lymphangiomatosis remains elusive. Development of more robust, recapitulative models will also be invaluable to investigate new and emerging therapeutics for the often devastating disease of systemic lymphangiomatosis. PMID:22196285

Rockson, Stanley G

2011-01-01

249

A digital transmission system for global maritime satellite communications  

Microsoft Academic Search

A digital transmission system for global maritime satellite communications has been designed, and experimental communications equipment has been developed, taking account of its potential application to the Inmarsat system where analog modulation is currently used for telephone signal transmission. This paper discusses possible digital technologies to realize an efficient digital transmission system, and presents a concept for the designed system.

Y. Hirata; Y. Yasuda; H. Okinaka; K. Kashiki

1984-01-01

250

Application of the Iridium Satellite System to Aeronautical Communications  

NASA Technical Reports Server (NTRS)

The next generation air transportation system will require greater air-ground communications capacity to accommodate more air traffic with increased safety and efficiency. Communications will remain primarily terrestrially based, but satellite communications will have an increased role. Inmarsat s aeronautical services have been approved and are in use for aeronautical safety communications provided by geostationary satellites. More recently the approval process for the Iridium low earth orbit constellation is nearing completion. The current Iridium system will be able to provide basic air traffic services communications suitable for oceanic, remote and polar regions. The planned second generation of the Iridium system, called Iridium NEXT, will provide enhanced capabilities and enable a greater role in the future of aeronautical communications. This paper will review the potential role of satellite communications in the future of air transportation, the Iridium approval process and relevant system testing, and the potential role of Iridium NEXT.

Kerczewski, Robert J.; Meza, Mike; Gupta, Om

2008-01-01

251

Establishing Conventional Communication Systems: Is Common Knowledge Necessary?  

ERIC Educational Resources Information Center

How do communities establish shared communication systems? The Common Knowledge view assumes that symbolic conventions develop through the accumulation of common knowledge regarding communication practices among the members of a community. In contrast with this view, it is proposed that coordinated communication emerges a by-product of local…

Barr, Dale J.

2004-01-01

252

Empirical Semantics of Agent Communication in Open Systems  

Microsoft Academic Search

The paper proposes a novel approach to the semantics of communication of self-interested and autonomous agents in open systems. It deflnes the semantics of communicative acts primarily as the observable efiect of their actual use in social encounters, and difiers thus fundamentally from men- talistic and current objectivist approaches to the semantics of agent communication languages. Empirical communica- tion semantics

Matthias Nickles; Gerhard Weiss

2003-01-01

253

A Hybrid Radio Frequency and Broadcast Visible Light Communication System  

E-print Network

, limited available spectrum and limited ability to scale with increasing demand. Directional communications Workshop on Optical Wireless Communications, December 5 - 9, 2011, Houston, Texas, USA. This workA Hybrid Radio Frequency and Broadcast Visible Light Communication System Michael B. Rahaim , Anna

254

Shared Communications: Volume 2. In-Depth Systems Research  

SciTech Connect

This report is the second of two documents that examine the literature for actual examples of organizations and agencies that share communications resources. While the primary emphasis is on rural, intelligent transportation system (ITS) communications involving transit, examples will not be limited to rural activities, nor to ITS implementation, nor even to transit. In addition, the term ''communication'' will be broadly applied to include all information resources. The first document of this series, ''Shared Communications: Volume I. A Summary and Literature Review'', defines the meaning of the term ''shared communication resources'' and provides many examples of agencies that share resources. This document, ''Shared Communications: Volume II. In-Depth Systems Research'', reviews attributes that contributed to successful applications of the sharing communication resources concept. A few examples of each type of communication sharing are provided. Based on the issues and best practice realworld examples, recommendations for potential usage and recommended approaches for field operational tests are provided.

Truett, LF

2004-09-22

255

SAW based systems for mobile communications satellites  

NASA Technical Reports Server (NTRS)

Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

Peach, R. C.; Miller, N.; Lee, M.

1993-01-01

256

Using Sequence Diagrams to Detect Communication Problems Between Systems  

NASA Technical Reports Server (NTRS)

Many software systems are evolving complex system of systems (SoS) for which inter-system communication is both mission-critical and error-prone. Such communication problems ideally would be detected before deployment. In a NASA-supported Software Assurance Research Program (SARP) project, we are researching a new approach addressing such problems. In this paper, we show that problems in the communication between two systems can be detected by using sequence diagrams to model the planned communication and by comparing the planned sequence to the actual sequence. We identify different kinds of problems that can be addressed by modeling the planned sequence using different level of abstractions.

Lindvall, Mikael; Ackermann, Chris; Stratton, William C.; Sibol, Deane E.; Ray, Arnab; Yonkwa, Lyly; Kresser, Jan; Godfrey, Sally H.; Knodel, Jens

2008-01-01

257

NASA Workshop on Animal Gravity-Sensing Systems  

NASA Technical Reports Server (NTRS)

The opportunity for space flight has brought about the need for well-planned research programs that recognize the significance of space flight as a scientific research tool for advancing knowledge of life on Earth, and that utilize each flight opportunity to its fullest. For the first time in history, gravity can be almost completely eliminated. Thus, studies can be undertaken that will help to elucidate the importance of gravity to the normal functioning of living organisms, and to determine the effects microgravity may have on an organism. This workshop was convened to organize a plan for space research on animal gravity-sensing systems and the role that gravity plays in the development and normal functioning of these systems. Scientists working in the field of animal gravity-sensing systems use a wide variety of organisms in their research. The workshop presentations dealt with topics which ranged from the indirect gravity receptor of the water flea, Daphnia (whose antennal setae apparently act as current-sensing receptors as the animal moves up and down in water), through specialized statocyst structures found in jellyfish and gastropods, to the more complex vestibular systems that are characteristic of amphibians, avians, and mammals.

Corcoran, M. L. (editor)

1986-01-01

258

OBJECT RECOGNITION IN THE ANIMATION SYSTEM Peter L. Stanchev, Boyan Dimitrov, Vladimir Rykov  

E-print Network

OBJECT RECOGNITION IN THE ANIMATION SYSTEM Peter L. Stanchev, Boyan Dimitrov, Vladimir Rykov This work is devoted to analyzing the syntax contents of an animation. In the paper we present the ANIMATION system ­ a system for animation scene and contents creation, retrieval and display. The object

Stanchev, Peter

259

A platform for ultra wideband communication systems  

E-print Network

In this thesis, a web interface for sending and receiving data across an actual UWB channel was designed. In addition, a platform for Ultra Wideband (UWB) communication development was implemented. The UWB communication ...

Ackerman, Nathan (Nathan Joseph)

2005-01-01

260

Tone-activated, remote, alert communication system  

NASA Technical Reports Server (NTRS)

Pocket sized transmitter, frequency modulated by crystal derived tones, with integral loop antenna provides police with easy operating alert signal communicator which uses patrol car radio to relay signal. Communication channels are time shared by several patrol units.

Baker, C. D.; Couvillon, L. A.; Hubbard, W. P.; Kollar, F. J.; Postal, R. B.; Tegnelia, C. R.

1971-01-01

261

Impact of fieldbus on communication in robotic systems  

Microsoft Academic Search

The aim of this paper is to discuss the problems relating to communication in distributed process control, highlighting the limits of traditional centralized communication systems based on point-to-point connections. The paper shows the real advantages that can be obtained by using a distributed common-bus communication system in time-critical process control applications, highlighting its impact on the architecture of control systems

Salvatore Cavalieri; A. di Stefano; O. Mirabella

1997-01-01

262

Communication in reactive multiagent robotic systems  

Microsoft Academic Search

Multiple cooperating robots are able to complete many tasks more quickly and reliably than one robot alone. Communication between the robots can multiply their capabilities and effectiveness, but to what extent? In this research, the importance of communication in robotic societies is investigated through experiments on both simulated and real robots. Performance was measured for three different types of communication

Tucker R. Balch; Ronald C. Arkin

1994-01-01

263

Group Support Systems and Deceptive Communication  

Microsoft Academic Search

Electronic communication is becoming more pervasive worldwide with the spread of the Internet, especially through the World Wide Web and electronic mail. Yet, as with all human communication, electronic communication is vulnerable to deceit on the part of senders, and to the less than stellar performance of most people at defecting deceit aimed at them. Despite considerable research over the

Joey F. George; John R. Carlson

1999-01-01

264

Radiation-hardened microwave communications system  

SciTech Connect

To develop a wireless communication system to meet the stringent requirements for a nuclear hot cell and similar environments, including control of advanced servomanipulators, a microwave signal transmission system development program was established to produce a demonstration prototype for the Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory (ORNL). Proof-of-principle tests in a partially metal lined enclosure at ORNL successfully demonstrated the feasibility of directed microwave signal transmission techniques for remote systems applications. The potential for much more severe radio-frequency (RF) multipath propagation conditions in fully metal lined cells led to a programmatic decision to conduct additional testing in more typical hot-cell environments at other sites. Again, the test results were excellent. Based on the designs of the earlier systems, an advanced microwave signal transmission system configuration was subsequently developed that, in highly reflective environments, will support both high-performance video channels and high baud-rate digital data links at total gamma dose tolerance levels exceeding 10{sup 7} rads and at elevated ambient temperatures.

Smith, S.F.; Bible, D.W.; Crutcher, R.I.; Hannah, J.H.; Moore, J.A.; Nowlin, C.H.; Vandermolen, R.I. [Oak Ridge National Lab., TN (United States); Chagnot, D.; LeRoy, A. [CEA Centre d`Etudes Nucleaires de Grenoble, 38 (France)

1993-03-01

265

Radiation-hardened microwave communications system  

SciTech Connect

To develop a wireless communication system to meet the stringent requirements for a nuclear hot cell and similar environments, including control of advanced servomanipulators, a microwave signal transmission system development program was established to produce a demonstration prototype for the Consolidated Fuel Reprocessing Program at Oak Ridge National Laboratory (ORNL). Proof-of-principle tests in a partially metal lined enclosure at ORNL successfully demonstrated the feasibility of directed microwave signal transmission techniques for remote systems applications. The potential for much more severe radio-frequency (RF) multipath propagation conditions in fully metal lined cells led to a programmatic decision to conduct additional testing in more typical hot-cell environments at other sites. Again, the test results were excellent. Based on the designs of the earlier systems, an advanced microwave signal transmission system configuration was subsequently developed that, in highly reflective environments, will support both high-performance video channels and high baud-rate digital data links at total gamma dose tolerance levels exceeding 10[sup 7] rads and at elevated ambient temperatures.

Smith, S.F.; Bible, D.W.; Crutcher, R.I.; Hannah, J.H.; Moore, J.A.; Nowlin, C.H.; Vandermolen, R.I. (Oak Ridge National Lab., TN (United States)); Chagnot, D.; LeRoy, A. (CEA Centre d'Etudes Nucleaires de Grenoble, 38 (France))

1993-01-01

266

Assessment of a new CT system for small animals  

Microsoft Academic Search

We have developed an X-ray cone beam tomograph for in vivo small-animal imaging using a flat panel detector (CMOS technology with a columnar CsI scintillator plate) and a microfocus X-ray source in a geometric configuration with 1.6 magnification and 7.5 cm2 field of view. This work presents an initial characterization of this new system. We measured the detector modulation transfer

S. Redondo; J. J. Vaquero; E. Lage; M. Abella; G. Tapias; A. Udias; M. Desco

2006-01-01

267

16.36 Communication Systems Engineering, Spring 2003  

E-print Network

Introduces the fundamentals of digital communications and networking. Topics covered include elements of information theory, sampling and quantization, coding, modulation, signal detection and system performance in the ...

Modiano, Eytan H.

268

Ultrawideband direct chaotic wireless communication systems and sensor networks  

Microsoft Academic Search

The ultrawideband communication facilities where chaotic radio pulses are used as an information carrier are considered. As perspective applications of such systems the wireless sensor networks are discussed.

A. S. Dmitriev; E. V. Efremova; A. V. Kletsov; L. V. Kuzmin; N. V. Rumyantsev

2010-01-01

269

High efficiency switching-mode amplifiers for wireless communication systems.  

E-print Network

??Switching-mode amplifiers represent attractive possibilities for RF wireless communication systems because their high efficiency can potentially extend the battery life time for portable devices, lower… (more)

Hung, Tsai-Pi

2008-01-01

270

Bioluminescent system for dynamic imaging of cell and animal behavior  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer We combined a yellow variant of GFP and firefly luciferase to make ffLuc-cp156. Black-Right-Pointing-Pointer ffLuc-cp156 showed improved photon yield in cultured cells and transgenic mice. Black-Right-Pointing-Pointer ffLuc-cp156 enabled video-rate bioluminescence imaging of freely-moving animals. Black-Right-Pointing-Pointer ffLuc-cp156 mice enabled tracking real-time drug delivery in conscious animals. -- Abstract: The current utility of bioluminescence imaging is constrained by a low photon yield that limits temporal sensitivity. Here, we describe an imaging method that uses a chemiluminescent/fluorescent protein, ffLuc-cp156, which consists of a yellow variant of Aequorea GFP and firefly luciferase. We report an improvement in photon yield by over three orders of magnitude over current bioluminescent systems. We imaged cellular movement at high resolution including neuronal growth cones and microglial cell protrusions. Transgenic ffLuc-cp156 mice enabled video-rate bioluminescence imaging of freely moving animals, which may provide a reliable assay for drug distribution in behaving animals for pre-clinical studies.

Hara-Miyauchi, Chikako [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan) [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Laboratory for Cell Function Dynamics, Brain Science Institute, RIKEN, Saitama 351-0198 (Japan); Department of Biophysics and Biochemistry, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Tokyo 113-8510 (Japan); Tsuji, Osahiko [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan) [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan); Hanyu, Aki [Division of Biochemistry, The Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo 135-8550 (Japan)] [Division of Biochemistry, The Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo 135-8550 (Japan); Okada, Seiji [Department of Advanced Medical Initiatives, Faculty of Medical Sciences, Kyushu University, Fukuoka 812-8582 (Japan)] [Department of Advanced Medical Initiatives, Faculty of Medical Sciences, Kyushu University, Fukuoka 812-8582 (Japan); Yasuda, Akimasa [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan) [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan); Fukano, Takashi [Laboratory for Cell Function Dynamics, Brain Science Institute, RIKEN, Saitama 351-0198 (Japan)] [Laboratory for Cell Function Dynamics, Brain Science Institute, RIKEN, Saitama 351-0198 (Japan); Akazawa, Chihiro [Department of Biophysics and Biochemistry, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Tokyo 113-8510 (Japan)] [Department of Biophysics and Biochemistry, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Tokyo 113-8510 (Japan); Nakamura, Masaya [Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan)] [Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan); Imamura, Takeshi [Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295 (Japan) [Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295 (Japan); Core Research for Evolutional Science and Technology, The Japan Science and Technology Corporation, Tokyo 135-8550 (Japan); Matsuzaki, Yumi [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan)] [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Okano, Hirotaka James, E-mail: hjokano@jikei.ac.jp [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Division of Regenerative Medicine Jikei University School of Medicine, Tokyo 150-8461 (Japan); and others

2012-03-09

271

Risk communication for critical civil infrastructure systems Jack Baker1  

E-print Network

1 Risk communication for critical civil infrastructure systems Jack Baker1 , Jason Coray2 , Paul De for communicating risk within the context of infrastructure management decision support systems. A generic model of a risk-based infrastructure management system is presented to illustrate important relationships of key

Baker, Jack W.

272

Airborne Communication Networks for Small Unmanned Aircraft Systems  

Microsoft Academic Search

This paper explores the role of meshed airborne communication networks in the operational performance of small unmanned aircraft systems. Small unmanned aircraft systems have the potential to create new applications and markets in civil domains, enable many disruptive technologies, and put considerable stress on air traffic control systems. We argue that of the existing networked communication architectures, only meshed ad

Eric W. Frew; Timothy X. Brown

2008-01-01

273

Research on the electromagnetic environment effect on wireless communication systems  

Microsoft Academic Search

With the increase in modern communication based on wireless technology, protection against electromagnetic environment effects (E3) on systems is becoming more important. This includes reducing the electromagnetic interference (EMI) and ensuring compatibility for communication systems within, and especially protecting data links and terminals against lightning and high-power electromagnetic pulse (HEMP) to achieve the normal operation of these systems. This paper

Zhou Changlin; Zhan Zhan; Qin Xuebing; Yang Hongtao; Zhu Weidong

2008-01-01

274

COSMO: a communication scheme for cooperative knowledge-based systems  

Microsoft Academic Search

The purpose of this paper is to present the design principles and features of a communication scheme that has been used to support cooperative problem solving within a network of knowledge-based systems. In presenting this account, we attempt to answer a set of critical yet unsettled questions of cooperative systems communication, such as when and how a knowledge-based system knows

Stephen T. C. Wong

1993-01-01

275

Meteor burst data communication for the Nile River irrigation system  

Microsoft Academic Search

The authors review the design, architecture, and operation of the Nile River Irrigation Data Collection System. The theory and the basic concepts of meteor burst data communication are briefly discussed. The system network architecture, the communication protocols, and the data formats are described in detail along with the functional design and the system operation. Results obtained from a command area

S. Abou-Zeid; A. El-Sherbini; M. El-Soudani

1989-01-01

276

Architecting Communication Network of Networks for Space System of Systems  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) are planning Space System of Systems (SoS) to address the new challenges of space exploration, defense, communications, navigation, Earth observation, and science. In addition, these complex systems must provide interoperability, enhanced reliability, common interfaces, dynamic operations, and autonomy in system management. Both NASA and the DoD have chosen to meet the new demands with high data rate communication systems and space Internet technologies that bring Internet Protocols (IP), routers, servers, software, and interfaces to space networks to enable as much autonomous operation of those networks as possible. These technologies reduce the cost of operations and, with higher bandwidths, support the expected voice, video, and data needed to coordinate activities at each stage of an exploration mission. In this paper, we discuss, in a generic fashion, how the architectural approaches and processes are being developed and used for defining a hypothetical communication and navigation networks infrastructure to support lunar exploration. Examples are given of the products generated by the architecture development process.

Bhasin, Kul B.; Hayden, Jeffrey L.

2008-01-01

277

Animal Health Policy and Practice: Scaling-up Community-based Animal Health Systems, Lessons from Human Health  

Microsoft Academic Search

In an extensive literature review, the author develops policy recommendations to facilitate scaling up community-based animal health systems to the national level. Noting that human and animal health services in rural areas have much in common, and that an extensive literature studies policy regarding primary healthcare for humans exists, she surveys that literature for observations and conclusions applicable to policy

Ana Riviere-Cinnamond

2005-01-01

278

Mobile satellite communications systems: Toward global personal communications  

Microsoft Academic Search

The constraints imposed by the RF environment are reviewed. An overview of present and planned mobile satellite systems is given. Present systems refer to those already in operation, while planned systems refer to those that have authority to offer the services and have either a satellite in orbit or one being built to support the systems. Future directions for mobile

John H. Lodge

1991-01-01

279

Social media and its dual use in biopreparedness: communication and visualization tools in an animal bioterrorism incident.  

PubMed

This article focuses on social media and interactive challenges for emergency organizations during a bioterrorism or agroterrorism incident, and it outlines the dual-use dilemma of social media. Attackers or terrorists can use social media as their modus operandi, and defenders, including emergency organizations in law enforcement and public and animal health, can use it for peaceful purposes. To get a better understanding of the uses of social media in these situations, a workshop was arranged in Stockholm, Sweden, to raise awareness about social media and animal bioterrorism threats. Fifty-six experts and crisis communicators from international and national organizations participated. As a result of the workshop, it was concluded that emergency organizations can collect valuable information and monitor social media before, during, and after an outbreak. In order to make use of interactive communication to obtain collective intelligence from the public, emergency organizations must adapt to social networking technologies, requiring multidisciplinary knowledge in the fields of information, communication, IT, and biopreparedness. Social network messaging during a disease outbreak can be visualized in stream graphs and networks showing clusters of Twitter and Facebook users. The visualization of social media can be an important preparedness tool in the response to bioterrorism and agroterrorism. PMID:23971817

Sjöberg, Elisabeth; Barker, Gary C; Landgren, Jonas; Griberg, Isaac; Skiby, Jeffrey E; Tubbin, Anna; von Stapelmohr, Anne; Härenstam, Malin; Jansson, Mikael; Knutsson, Rickard

2013-09-01

280

MSFC Skylab instrumentation and communication system mission evaluation  

NASA Technical Reports Server (NTRS)

An evaluation of the in-orbit performance of the instrumentation and communications systems installed on Skylab is presented. Performance is compared with functional requirements and the fidelity of communications. In-orbit performance includes processing engineering, scientific, experiment, and biomedical data, implementing ground-generated commands, audio and video communication, generating rendezvous ranging information, and radio frequency transmission and reception. A history of the system evolution based on the functional requirements and a physical description of the launch configuration is included. The report affirms that the instrumentation and communication system satisfied all imposed requirements.

Adair, B. M.

1974-01-01

281

Suitability of ANSI standards for quantifying communication satellite system performance  

NASA Technical Reports Server (NTRS)

A study on the application of American National Standards X3.102 and X3.141 to various classes of communication satellite systems from the simple analog bent-pipe to NASA's Advanced Communications Technology Satellite (ACTS) is discussed. These standards are proposed as means for quantifying the end-to-end communication system performance of communication satellite systems. An introductory overview of the two standards are given followed by a review of the characteristics, applications, and advantages of using X3.102 and X3.141 to quantify with a description of the application of these standards to ACTS.

Cass, Robert D.

1988-01-01

282

Multi-Agent System Dynamics: Bifurcation and Behavior of Animal Groups  

E-print Network

Multi-Agent System Dynamics: Bifurcation and Behavior of Animal Groups Naomi Ehrich Leonard of collective animal behavior. Animals in groups, from bird flocks to fish schools, employ decentralized: Multi-agent systems, Coordinated control, Nonlinear dynamics, Collective animal behavior, Social

Leonard, Naomi

283

Picture archiving and communication systems (PACS).  

PubMed

Over the past 2 decades, groups of computer scientists, electronic design engineers, and physicians, in universities and industry, have worked to achieve an electronic environment for the practice of medicine and radiology. The radiology component of this revolution is often called PACS (picture archiving and communication systems). More recently it has become evident that the efficiencies and cost savings of PACS are realized when they are part of an enterprise-wide electronic medical record. The installation of PACS requires careful planning by all the various stakeholds over many months prior to installation. All of the users must be aware of the initial disruption that will occur as they become familiar with the systems. Modern fourth generation PACS is linked to radiology and hospital information systems. The PACS consist of electronic acquisition sites-a robust network intelligently managed by a server, multiple viewing sites, and an archive. The details of how these are linked and their workflow analysis determines the success of PACS. PACS evolves over time, components are frequently replaced, and so the users must expect continuous learning about new updates and improved functionality. The digital medical revolution is rapidly being adopted in many medical centers, improving patient care and the success of the institution. PMID:12867813

Gamsu, Gordon; Perez, Enrico

2003-07-01

284

The Effect of Cognitive Type and Communications Style on the Communication of Management Information System Concepts.  

ERIC Educational Resources Information Center

Results of exploratory investigation indicate that failures to communicate management information systems (MIS) concepts can result from the sender's communication style being inappropriate to the receiver's cognitive type. Details of the research methodology, analysis of variance, and summary of results are given, as well as recommendations for…

Davis, Donald L.

1983-01-01

285

Communication Systems for Grid Integration of Renewable Energy Resources  

E-print Network

There is growing interest in renewable energy around the world. Since most renewable sources are intermittent in nature, it is a challenging task to integrate renewable energy resources into the power grid infrastructure. In this grid integration, communication systems are crucial technologies, which enable the accommodation of distributed renewable energy generation and play extremely important role in monitoring, operating, and protecting both renewable energy generators and power systems. In this paper, we review some communication technologies available for grid integration of renewable energy resources. Then, we present the communication systems used in a real renewable energy project, Bear Mountain Wind Farm (BMW) in British Columbia, Canada. In addition, we present the communication systems used in Photovoltaic Power Systems (PPS). Finally, we outline some research challenges and possible solutions about the communication systems for grid integration of renewable energy resources.

Yu, F Richard; Xiao, Weidong; Choudhury, Paul

2011-01-01

286

Advanced integrated WDM system for POF communication  

NASA Astrophysics Data System (ADS)

Polymer Optical Fibres (POFs) show clear advantages compared to copper and glass fibres. In essence, POFs are inexpensive, space-saving and not susceptible to electromagnetic interference. Thus, the usage of POFs have become a reasonable alternative in short distance data communication. Today, POFs are applied in a wide number of applications due to these specific advantages. These applications include automotive communication systems and in-house-networks. State-of-the-art is to transmit data with only one channel over POF, this limits the bandwidth. To solve this problem, an integrated MUX/DEMUX-element for WDM over POF is designed and developed to use multiple channels. This integration leads to low costs, therefore this component is suitable for mass market applications. The fundamental idea is to separate the chromatic parts of the light in its monochromatic components by means of a grating based on an aspheric mirror. Due to the high NA of the POF the setup has to be designed in a 3D-approach. Therefore this setup cannot be compared with the planar solutions available on market, they would result high losses in the 3rd dimension. To achieve a fast and optimized design an optical simulation program is used. Particular attention has to be paid to the design of the POF as a light source in the simulation program and the optimisation of the grating. The following realization of the demultiplexer is planed to be done with injection molding. This technology offers easy and very economical processing. These advantages make this technology first choice for optical components in the low-cost array.

Haupt, M.; Fischer, U. H. P.

2009-01-01

287

DOLPHIN for inter-vehicle communications system  

Microsoft Academic Search

Inter-vehicle communications (IVC) technology for group cooperative driving has been studied by the Association of Electronic Technology for Automobile Traffic and Driving (JSK) since 1980 in Japan. The study of the IVC technology has been focussed on the communication protocol. This paper proposes DOLPHIN (dedicated omni-purpose inter-vehicle communication linkage protocol for highway automation) and presents its performance evaluation results

K. Tokuda; M. Akiyama; H. Fujii

2000-01-01

288

Communication.  

ERIC Educational Resources Information Center

The following essays on communication are presented: communication as a condition of survival, communication for special purposes, the means of transmission of communication, communication within social and economic structures, the teaching of communication through the press, the teaching of modern languages, communication as a point of departure,…

Strauss, Andre

289

Technology Evaluation of Programmable Communicating Thermostats with Radio Broadcast Data System Communications  

SciTech Connect

Programmable Communicating Thermostats are thermostats that can be programmed by the user to respond to signals indicating a grid-level system emergency or pricing event. The California Energy Commission is considering standards that would include a requirement for Programmable Communicating Thermostats in residential and small commercial applications. The current specification for Programmable Communicating Thermostats requires Radio Data System communications to Programmable Communicating Thermostats. This study tested the signal strength and reliability of Radio Data System signals at 40 customer sites within the Sacramento Municipal Utility District, which is serviced by 17 radio stations that already transmit Radio Data System signals. The study also tested the functionality of a commercially available Programmable Communicating Thermostat for compliance with California Energy Commission design standards. Test results demonstrated that Radio Data System is capable of reliably sending price and emergency signals. This study also provides evidence that existing Programmable Communicating Thermostats, on receiving a Radio Data System pricing or event signal, are capable of automatically increasing set points to a customer-determined or utility-determined level, thus providing air-conditioning demand response within seconds or just a few (less than 5) minutes.

Herter, Karen; Wayland, Seth

2008-10-31

290

Low earth orbit satellite based communication systems — Research opportunities  

Microsoft Academic Search

Telecommunication systems are undergoing revolutionary changes that are transforming society, changing the way in which industrial and service organizations operate, and are having a profound effect on the daily life of individuals. Low earth orbit satellite (LEOS) based communication systems are a new and exciting endeavor in reshaping the global communication network and the services that it provides. Huge investments

Bezalel Gavish

1997-01-01

291

The Hospital at Night (H@N) Wireless Communication System  

E-print Network

The Hospital at Night (H@N) Wireless Communication System: Evridiki (Evie) Fioratou1 [Evridiki of Technology Centre for Healthcare, University of Nottingham, 2 Respiratory Biomedical Research Unit A new wireless communication system implemented at Nottingham has been shown to enhance patient safety

Oakley, Jeremy

292

Multiple-User Adaptive-Array Communication System  

NASA Technical Reports Server (NTRS)

Weights for K-beam system computed K/6 times faster. In single-frequency adaptive-array communication system in whick K mobile users communicate with central station equipped with n-antenna array. Each K signal recoverable by taking specific weighted sum of n complex antenna voltages.

Zohar, S.

1985-01-01

293

Iridium{reg_sign} worldwide personal communication system  

SciTech Connect

The IRIDIUM system is a personal worldwide communication system designed to support portable, low power subscriber units through the use of a constellation of satellites in low earth polar orbit. The satellites are networked together to form a system which provides continuous line-of-sight communications between the IRIDIUM system and any point within 30 km of the earth{close_quote}s surface. The system architecture and operation are described. {copyright} {ital 1997 American Institute of Physics.}

Helm, J. [Senior Systems Engineer Motorola Mobile Satellite Systems Division 1600 W. Chandler Blvd., Suite 150 Chandler, Arizona85224 (United States)

1997-01-01

294

A dual micro-CT system for small animal imaging  

NASA Astrophysics Data System (ADS)

Micro-CT is a non-invasive imaging modality usually used to assess morphology in small animals. In our previous work, we have demonstrated that functional micro-CT imaging is also possible. This paper describes a dual micro-CT system with two fixed x-ray/detectors developed to address such challenging tasks as cardiac or perfusion studies in small animals. A two-tube/detector system ensures simultaneous acquisition of two projections, thus reducing scanning time and the number of contrast injections in perfusion studies by a factor of two. The system is integrated with software developed in-house for cardio-respiratory monitoring and gating. The sampling geometry was optimized for 88 microns in such a way that the geometric blur of the focal spot matches the Nyquist sample at the detector. A geometric calibration procedure allows one to combine projection data from the two chains into a single reconstructed volume. Image quality was measured in terms of spatial resolution, uniformity, noise, and linearity. The modulation transfer function (MTF) at 10% is 3.4 lp/mm for single detector reconstructions and 2.3 lp/mm for dual tube/detector reconstructions. We attribute this loss in spatial resolution to the compounding of slight errors in the separate single chain calibrations. The dual micro-CT system is currently used in studies for morphological and functional imaging of both rats and mice.

Badea, C. T.; Johnston, S.; Johnson, B.; Lin, M.; Hedlund, L. W.; Johnson, G. Allan

2008-03-01

295

Communications and control for electric power systems  

NASA Technical Reports Server (NTRS)

A long-term strategy for the integration of new control technologies for power generation and delivery is proposed: the industry would benefit from an evolutionary approach that would adapt to its needs future technologies as well as those that it has so far not heeded. The integrated operation of the entire system, including the distribution system, was proposed as a future goal. The AbNET communication protocols are reviewed, and additions that were made in 1991 are described. In the original network, traffic was controlled by polling at the master station, located at the substation, and routed by a flooding algorithm. In a revised version, the polling and flooding are modified. The question of interfacing low-energy measurement transducers or instrument transformers is considered. There is presently little or no agreement on what the output of optical current transducers (CT's) should be. Appendices deal with the calibration of current transducers; with Delta modulation, a simple means of serially encoding the output of an OCT; and with noise shaping, a method of digital signal processing that trades off the number of bits in a digital sample for a higher number of samples.

Kirkham, H.

1992-01-01

296

Gas Main Sensor and Communications Network System  

SciTech Connect

Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the Northeast Gas Association (NGA), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. This projected was completed in April 2006, and culminated in the installation of more than 2 dozen GasNet nodes in both low- and high-pressure cast-iron and steel mains owned by multiple utilities in the northeastern US. Utilities are currently logging data (off-line) and monitoring data in real time from single and multiple networked sensors over cellular networks and collecting data using wireless bluetooth PDA systems. The system was designed to be modular, using in-pipe sensor-wands capable of measuring, flow, pressure, temperature, water-content and vibration. Internal antennae allowed for the use of the pipe-internals as a waveguide for setting up a sensor network to collect data from multiple nodes simultaneously. Sensor nodes were designed to be installed with low- and no-blow techniques and tools. Using a multi-drop bus technique with a custom protocol, all electronics were designed to be buriable and allow for on-board data-collection (SD-card), wireless relaying and cellular network forwarding. Installation options afforded by the design included direct-burial and external polemounted variants. Power was provided by one or more batteries, direct AC-power (Class I Div.2) and solar-array. The utilities are currently in a data-collection phase and intend to use the collected (and processed) data to make capital improvement decisions, compare it to Stoner model predictions and evaluate the use of such a system for future expansion, technology-improvement and commercialization starting later in 2006.

Hagen Schempf

2006-05-31

297

The Communications link analysis and simulation system (CLASS)  

NASA Technical Reports Server (NTRS)

The Communications Link Analysis and Simulation System (CLASS) is a comprehensive, computerized communications and tracking system analysis tool under development by the Networks Directorate of the NASA/GSFC. The primary use of this system is to provide the capability to predict the performance of the Tracking and Data Relay Satellite system (TDRSS) User Communications and Tracking links through the TDRSS. The general capabilities and operational philosophy of the current and final versions of the CLASS are described along with some examples of analyses which have been performed utilizing the capabilities of this system.

Godfrey, R. D.

1985-01-01

298

Single Switch Chinese Phonetic Communication System  

Microsoft Academic Search

Morse code, with its single switch operation, has been shown to be an excellent adaptive communication device for the disabled, especially those with impaired hand coordination and dexterity. Because a stable typing rate is required for an accurate rec- ognition of Morse code, it presents a major hindrance to disabled persons in applying Morse code as a useful communication tool.

Cheng-hong Yang; Cheng-huei Yang; Li-yeh Chuang; Ching-hsing Luo

2002-01-01

299

Over-the-Horizon Optoelectronic Communication Systems  

NASA Astrophysics Data System (ADS)

Some theoretical and experimental results related to atmospheric optoelectronic communication are considered. The experiments were carried out to evaluate the feasibility of text information transmission through bistatic communication channels based on the effects of scattering and reflection under conditions of a cloudless or cloudy atmosphere and through plumes of artificial aerosol-gaseous media.

Belov, V. V.; Tarasenkov, M. V.; Abramochkin, V. N.; Troitskii, V. O.

2014-11-01

300

Human body communication system with FSBT  

Microsoft Academic Search

There are some leakage radiations from human body depending on incoming signals to it. As there are many noises in the frequency band spanning several MHz, human body communication (HBC), which is a technique to transfer various information through the human body as a communication channel, requires a limitation of frequencies and data rates to support a reliable network that

Hyung-il Park; In-gi Lim; Sungweon Kang; Whan-woo Kim

2010-01-01

301

An integrated, underwater optical \\/acoustic communications system  

Microsoft Academic Search

Communication underwater is severely limited when compared to communications in air because water is essentially opaque to electromagnetic radiation except in the visible band. Even in the visible band, light penetrates only a few hundred meters in the clearest waters and much less in waters made turbid by suspended sediment or high concentrations of marine life. Consequently, acoustic techniques have

N. Farr; A. Bowen; J. Ware; C. Pontbriand; M. Tivey

2010-01-01

302

Developing an Approach for Analyzing and Verifying System Communication  

NASA Technical Reports Server (NTRS)

This slide presentation reviews a project for developing an approach for analyzing and verifying the inter system communications. The motivation for the study was that software systems in the aerospace domain are inherently complex, and operate under tight constraints for resources, so that systems of systems must communicate with each other to fulfill the tasks. The systems of systems requires reliable communications. The technical approach was to develop a system, DynSAVE, that detects communication problems among the systems. The project enhanced the proven Software Architecture Visualization and Evaluation (SAVE) tool to create Dynamic SAVE (DynSAVE). The approach monitors and records low level network traffic, converting low level traffic into meaningful messages, and displays the messages in a way the issues can be detected.

Stratton, William C.; Lindvall, Mikael; Ackermann, Chris; Sibol, Deane E.; Godfrey, Sally

2009-01-01

303

Effects on Communicative Requesting and Speech Development of the Picture Exchange Communication System in Children with Characteristics of Autism  

ERIC Educational Resources Information Center

Few studies on augmentative and alternative communication (AAC) systems have addressed the potential for such systems to impact word utterances in children with autism spectrum disorders (ASD). The Picture Exchange Communication System (PECS) is an AAC system designed specifically to minimize difficulties with communication skills experienced by…

Ganz, Jennifer B.; Simpson, Richard L.

2004-01-01

304

Effects on Communicative Requesting and Speech Development of the Picture Exchange Communication System in Children with Characteristics of Autism  

Microsoft Academic Search

Few studies on augmentative and alternative communication (AAC) systems have addressed the potential for such systems to impact word utterances in children with autism spectrum disorders (ASD). The Picture Exchange Communication System (PECS) is an AAC system designed specifically to minimize difficulties with communication skills experienced by individuals with ASD. The current study examined the role of PECS in improving

Jennifer B. Ganz; Richard L. Simpson

2004-01-01

305

Coded error probability evaluation for antijam communication systems  

NASA Technical Reports Server (NTRS)

We present a general union-Chernoff bound on the bit error probability for coded communication systems and apply it to examples of antijam systems. The key feature of this bound is the decoupling of the coding aspects of the system from the remaining part of the communication system which includes jamming, suboptimum detectors, and arbitrary decoding metrics which may or may not use jammer state knowledge

Omura, J. K.; Levitt, B. K.

1982-01-01

306

Expert system for processing errors in a multiplex communications systems  

SciTech Connect

This patent describes a method to analyze errors in a system. The system having a plurality of resources with replaceable units, a display, a processor, and memory means for storing decision trees, data structures, and error analysis tasks. The resources including a diagnostics card having a processor and memory means for storing resource analysis tasks, and communication resources. The method comprising the steps of: testing the resources intermittently by the error analysis tasks invoking a card analysis task on the diagnostics card to test for an error in the communication resources in the system; detecting an error and invoking an appropriate error analysis task to further diagnose the cause of the error; isolating the error to a replaceable unit by automatically traversing the decision trees in the error analysis task on the diagnostics card; writing data to record the error in the data structure in the memory of the system; and displaying a message indicative of the error on the display of the system.

Clark, M.E.; Greever, R.G.; Schmier, L.J.; Wong, J.D.

1989-11-14

307

Human-visual-system-based scalable video coding and communications  

NASA Astrophysics Data System (ADS)

This paper introduces our recent research work on the development of a scalable foveated visual information coding and communication system, which follows two emerging trends in visual communication research. One is to design rate scalable image and video codecs, which allow the extraction of coded visual information at continuously varying bit rates from a single compressed bitstream. The other is to incorporate human visual system models to improve the state-of-the-art of image and video coding techniques by better exploiting the properties of the intended receiver. The central idea of the proposed system is to organize the encoded bitstream to provide the best decoded visual information at an arbitrary bit rate in terms of foveated visual quality measurement. Such a scalable foveated visual information processing system has many potential applications in the field of visual communications. Significant examples include network image browsing, network videoconferencing, robust visual communication over noisy channels, and visual communication over active networks.

Lu, Ligang; Wang, Zhou; Kouloheris, Jack L.; Bovik, Alan C.

2002-09-01

308

PM: An Operating System Coordinated High Performance Communication Library  

Microsoft Academic Search

. We have developed a new communication library, called PM,for the Myrinet gigabit LAN card, that has a dedicated processor andon-board memory to handle a communication protocol. In order to obtainhigh performance communication and support a multi-user environment,we have co-desgined PM, an operating system realized by adaemon process, and the run-time routine for a programming language.Several unique features, e.g., network

Hiroshi Tezuka; Atsushi Hori; Yutaka Ishikawa; Mitsuhisa Sato

1997-01-01

309

ASTP communications systems analyses and performance predictions  

NASA Technical Reports Server (NTRS)

A research program was conducted to provide ASTP mission communication coverage and performance analyses and to analyze anomalies and special compatibility problems as they arise. The end product of the contract was spacecraft-to-ground communications performance predictions for the ASTP mission, both for direct communication links to ground and for those links via the ATS-6 relay satellite to ground. Solutions are given for the special mission anomalies and compatibility problems encountered. A brief summary describing the work activities expended is given.

1975-01-01

310

Multi-Agent System Dynamics: Bifurcation and Behavior of Animal Groups  

E-print Network

Multi-Agent System Dynamics: Bifurcation and Behavior of Animal Groups Naomi Ehrich Leonard of collective animal behavior. Animals in groups, from bird flocks to fish schools, employ decentralized-performing dynamics drawn from observations and understanding of collective behavior in animal groups. The study

Leonard, Naomi

311

Principles of Communications Textbook : Communication Systems , 4th Edition  

E-print Network

·Linear Time-Invariant Filter ( System ) ·Power Spectral Density ( PSD ) ·Gaussian Process ·Noise ·Narrowband Noise ·Representation of Narrowband Noise (I,Q, Envelope and phase ) ·Sinusoidal Wave Plus Narrowband Noise 9 #12;Chapter 2 Continuous-Wave ( CW ) Modulation ·Amplitude Modulation (AM) ·Linear

Hung, Shih-Hao

312

Principles of Communications Textbook : Communication Systems , 4th Edition  

E-print Network

Functions ·Ergodic Processes ·Linear Time-Invariant Filter ( System ) ·Power Spectral Density ( PSD ) ·Gaussian Process ·Noise ·Narrowband Noise ·Representation of Narrowband Noise (I,Q, Envelope and phase ) ·Sinusoidal Wave Plus Narrowband Noise 26 #12;Chapter 2 Continuous-Wave ( CW ) Modulation ·Amplitude

Hung, Shih-Hao

313

Relating Communications Mode Choice and Teamwork Quality: Conversational versus Textual Communication in IT System and Software Development Teams  

ERIC Educational Resources Information Center

This cross-sectional study explored how IT system and software development team members communicated in the workplace and whether teams that used more verbal communication (and less text-based communication) experienced higher levels of collaboration as measured using the Teamwork Quality (TWQ) scale. Although computer-mediated communication tools…

Smith, James Robert

2012-01-01

314

Limitation to Communication of Fermionic System in Accelerated Frame  

NASA Astrophysics Data System (ADS)

In this article, we investigate communication between an inertial observer and an accelerated observer, sharing fermionic system, when they use classical and quantum communication using single rail or dual rail encoding. The purpose of this work is to understand the limit to the communication between an inertial observer and an accelerated observer, with single rail or dual rail encoding of fermionic system. We observe that at the infinite acceleration, the coherent information of single(or double) rail quantum channel vanishes, but those of classical ones may have finite values. In addition, we see that even when considering a method beyond the single-mode approximation, for the communication between Alice and Bob, the dual rail entangled state seems to provide better information transfer than the single rail entangled state, when we take a fixed choice of the Unruh mode. Moreover, we find that the single-mode approximation may not be sufficient to analyze communication of fermionic system in an accelerated frame.

Chang, Jinho; Kwon, Younghun

2014-09-01

315

Theatre of the Mind: A Project to Animate the Language of thought and Communication  

ERIC Educational Resources Information Center

Human language is a rich and complex part of human behaviour that can be studied in many ways. The author and his colleagues are developing an application that accepts simple texts as input and presents an animated display of characters acting out the text. It mimics the human visualization of texts, the so-called Theatre of the Mind. In so doing,…

Wheeler, Eric S.

2009-01-01

316

Research Summary Assessing and communicating animal disease risks for countryside users  

E-print Network

initially on Lyme disease, an infection caused by a spiral bacteria Borrelia burgdorferi that is found in a number of wild animal hosts and which can be transferred to humans by infected ticks. Lyme disease in Lyme disease resulting from changes in environmental factors mdevelop appropriate risk assessment

317

EE 430: Communications Systems Course Syllabus: Fall 2010  

E-print Network

Filtering Ch. 11 11 Carrier Recovery and PLL Ch. 10 12 FSK Modulation/Demodulation and FM 13 Review and Exam Communication System Components Ch. 2 and 3 3 Noise in Communications Ch. 4 4 Modulation and Demodulation Ch. 5 5 Quadrature Modulation and Demodulation 6 Sampling, Aliasing and Interpolation Ch. 6 7 Review

Howard, Sheryl

318

ELEC3028 Digital Transmission MODEM S Chen Digital Communication System  

E-print Network

ELEC3028 Digital Transmission ­ MODEM S Chen Digital Communication System · Purpose: communicate: rate, quality spectral bandwidth requirement · Major components: CODEC, MODEM and channel modulation input output CODEC MODEM Medium 1 #12;ELEC3028 Digital Transmission ­ MODEM S Chen Digital

Chen, Sheng

319

Timely and energy-efficient communications in rural infostation systems  

Microsoft Academic Search

The infostation communication paradigm represents a good trade-off between the size of investments in infrastructure and the connectivity needs in rural areas. In fact, exploiting the emerging mesh networking technologies, infostations can be deployed with low cost. In infostation systems, mobile nodes achieve network connectivity when they are in the radio coverage of the infostation. Nevertheless, preliminary to the communication,

Laura Galluccio; Alessandro Leonardi; Giacomo Morabito; Sergio Palazzo

2008-01-01

320

Adaptive Beamforming in Mobile, Massively Multiuser Satellite Communications: A System  

E-print Network

Adaptive Beamforming in Mobile, Massively Multiuser Satellite Communications: A System Perspective Xiao Lei, Laura Cottatellucci, Samah A. M. Ghanem Mobile Communications Department, Eurecom, France Email: {xiao.lei; laura.cottatellucci; samah.ghanem}@eurecom.fr Abstract--We consider a Mobile Satellite

Gesbert, David

321

Transport System Architectures for High-Performance Communications Subsystems  

E-print Network

Transport System Architectures for High-Performance Communications Subsystems Douglas C. Schmidt as CPU(s), virtual memory, and network adapters) together with communication pro- tocols (such as TCP/IP subsystem, the x-kernel, and the Conduit framework from the Choices oper- atingsystem. This paper

Schmidt, Douglas C.

322

Frequency allocation problem in a SDMA satellite communication system  

E-print Network

Frequency allocation problem in a SDMA satellite communication system Laurent Houssina SDMA (Spatial Division Multiple Access) is a principle of radio resource sharing that relies on the division of the space dimension into separated communication channels. SDMA basically relies on adaptive

Boyer, Edmond

323

An Experimental Study of the Emergence of Human Communication Systems  

Microsoft Academic Search

The emergence of human communication systems is typically investigated via 2 approaches with complementary strengths and weaknesses: naturalistic studies and computer simulations. This study was conducted with a method that combines these approaches. Pairs of participants played video games requiring communication. Members of a pair were physically separated but exchanged graphic signals through a medium that prevented the use of

Bruno Galantucci

2005-01-01

324

System for Integrated Language Communications Observation, SILCO. Observer Manual.  

ERIC Educational Resources Information Center

This observer's manual is designed to familiarize people with the System for Integrated Language Communications Observation (SILCO), which rates the degree of integrated language communications instruction occurring in elementary classrooms during 40-minute time blocks. Sections of the manual discuss SILCO's development, organization,…

Bratton, Mary Elizabeth Cataldi

325

The Development of the System for Integrated Language Communications Observation.  

ERIC Educational Resources Information Center

The System for Integrated Language Communications Observation (SILCO) was developed to provide descriptive information about integrated language communication instruction. Such instruction is defined as that which interrelates listening, speaking, reading, and writing through developmental sequences of skills resources and activities and provides…

Bratton, Mary Cataldi

326

The Value System--A False Prophet for Intercultural Communication.  

ERIC Educational Resources Information Center

The author questions the applicability of a value-system-contrast approach to intercultural communication. His two main reservations involve the deprivation and validity of value sets themselves and the potential dangers encounterable in using values as a guide to intercultural communication. Firstly, the non-scientific methods employed in…

Holladay, Howard P.

327

78 FR 31576 - Enforcement Proceeding; Certain Two-Way Global Satellite Communication Devices, System and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Certain Two-Way Global Satellite Communication Devices, System and Components...certain two-way global satellite communication devices, system and components...importation any two-way global satellite communication devices, system,...

2013-05-24

328

77 FR 58579 - Certain Two-Way Global Satellite Communication Devices, System and Components Thereof...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Certain Two-Way Global Satellite Communication Devices, System and Components...certain two-way global satellite communication devices, system and components...certain two-way global satellite communication devices, system and...

2012-09-21

329

10 CFR 73.54 - Protection of digital computer and communication systems and networks.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Protection of digital computer and communication systems and networks...Sites § 73.54 Protection of digital computer and communication systems and networks...shall provide high assurance that digital computer and communication systems and...

2014-01-01

330

10 CFR 73.54 - Protection of digital computer and communication systems and networks.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Protection of digital computer and communication systems and networks...Sites § 73.54 Protection of digital computer and communication systems and networks...shall provide high assurance that digital computer and communication systems and...

2013-01-01

331

10 CFR 73.54 - Protection of digital computer and communication systems and networks.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Protection of digital computer and communication systems and networks...73.54 Protection of digital computer and communication systems and networks...provide high assurance that digital computer and communication systems and...

2010-01-01

332

Multiple-antenna communication systems: an emerging technology  

Microsoft Academic Search

A recent development in wireless communications is the application of multiple-input multiple-output (MIMO) systems to radio communications via use of multiple antennas. In order to investigate the technologys potential, an experimental MIMO system containing two four-element antenna arrays (4x4) has been developed at the University of Alberta. The system is used to obtain MIMO channel measurements in a typical indoor

Paul Goud Jr; Christian Schlegel; W. A. Krzymien; Robert Hang

2004-01-01

333

The design of static and mobile HF communication systems  

Microsoft Academic Search

The lecture deals with more specific aspects of HF communication system design arising from a previous lecture entitled HF system design principles presented as part of AGARD Lecture Series 127 in 1983. The major topics considered are: (1) the design of point-to-point systems; (2) the design of systems involving mobile terminals; (3) system control and frequency management; (4) resistance to

M. Darnell

1986-01-01

334

Facility for the evaluation of space communications and related systems  

NASA Technical Reports Server (NTRS)

NASA Lewis Research Center's Communications Projects Branch has developed a facility for the evaluation of space communications systems and related types of systems, called the Advanced Space Communications (ASC) Laboratory. The ASC Lab includes instrumentation, testbed hardware, and experiment control and monitor software for the evaluation of components, subsystems, systems, and networks. The ASC lab has capabilities to perform radiofrequency (RF), microwave, and millimeter-wave characterizations as well as measurements using low, medium, or high data rate digital signals. In addition to laboratory measurements, the ASC Lab also includes integrated satellite ground terminals allowing experimentation and measurements accessing operational satellites through real space links.

Kerczewski, Robert J.; Svoboda, James S.; Kachmar, Brian A.

1995-01-01

335

A satellite system for land-mobile communications in Europe  

NASA Technical Reports Server (NTRS)

There exists a great unsatisified demand for land mobile communications in Europe, particularly in sectors of business activity such as the road transport industry. This demand could best be satisfied by means of satellite-based private networks providing voice and data communications in a hub configuration. The potential market is estimated to encompass several hundred thousand road vehicles and the transmission capacity required would be several thousand channels. ESA is currently demonstrating the potential of satellite communications for this type of application, using a system called PRODAT. System studies are being performed with the aim of defining the architecture of a regional satellite system for Europe.

Bartholome, P.; Rogard, R.

1988-01-01

336

Ad-Hoc Communication and Localization System for Mobile Robots  

NASA Astrophysics Data System (ADS)

Robots exploring unknown territory cannot rely on fixed infrastructure for communication and localization purposes. Therefore an ad-hoc communication and localization system is required to provide such facilities. In this paper a solution for a radio based localization system is presented using a 2.4 GHz wireless radio transceiver based on Chirp Spread Spectrum (CSS) modulation, which allows distance measurements by evaluating the signal propagation delay. Using odometry data as additional information source a communication and positioning system is developed fulfilling ad-hoc demands.

Neuwinger, Bernd; Witkowski, Ulf; Rückert, Ulrich

337

Integrated system of white LED visible-light communication and power-line communication  

Microsoft Academic Search

White LED offers advantageous properties such as high brightness, reliability, lower power consumption and long lifetime. Indoor optical wireless communication systems employing white LED lighting have been proposed. This system will enable high quality of service by the high radiation power from this lighting equipment. And, this system does not cause or suffer from radio or electromagnetic interference. But, it

Toshihiko Komine; Masao Nakagawa

2003-01-01

338

ATCOM: Automatically Tuned Collective Communication System for SMP Clusters  

SciTech Connect

Conventional implementations of collective communications are based on point-to-point communications, and their optimizations have been focused on efficiency of those communication algorithms. However, point-to-point communications are not the optimal choice for modern computing clusters of SMPs due to their two-level communication structure. In recent years, a few research efforts have investigated efficient collective communications for SMP clusters. This dissertation is focused on platform-independent algorithms and implementations in this area. There are two main approaches to implementing efficient collective communications for clusters of SMPs: using shared memory operations for intra-node communications, and overlapping inter-node/intra-node communications. The former fully utilizes the hardware based shared memory of an SMP, and the latter takes advantage of the inherent hierarchy of the communications within a cluster of SMPs. Previous studies focused on clusters of SMP from certain vendors. However, the previously proposed methods are not portable to other systems. Because the performance optimization issue is very complicated and the developing process is very time consuming, it is highly desired to have self-tuning, platform-independent implementations. As proven in this dissertation, such an implementation can significantly out-perform the other point-to-point based portable implementations and some platform-specific implementations. The dissertation describes in detail the architecture of the platform-independent implementation. There are four system components: shared memory-based collective communications, overlapping mechanisms for inter-node and intra-node communications, a prediction-based tuning module and a micro-benchmark based tuning module. Each component is carefully designed with the goal of automatic tuning in mind.

Meng-Shiou Wu

2005-12-17

339

Development of automatic movement analysis system for a small laboratory animal using image processing  

NASA Astrophysics Data System (ADS)

Activity analysis in a small laboratory animal is an effective procedure for various bioscience fields. The simplest way to obtain animal activity data is just observation and recording manually, even though this is labor intensive and rather subjective. In order to analyze animal movement automatically and objectivity, expensive equipment is usually needed. In the present study, we develop animal activity analysis system by means of a template matching method with video recorded movements in laboratory animal at a low cost.

Nagatomo, Satoshi; Kawasue, Kikuhito; Koshimoto, Chihiro

2013-03-01

340

IEPLC Framework, Automated Communication in a Heterogeneous Control System Environment  

E-print Network

In CERN accelerators control system several components are essential such as: Programmable Logic Controller (PLC), PCI Extensions for Instrumentation (PXI), and other micro-controller families. Together with their weaknesses and their strength points they typically present custom communication protocols and it is therefore difficult to federate them into the control system using a single communication strategy. Furthermore this dependency to the physical device interfaces and protocols makes most of the code not reusable and the replacement of old technology a difficult problem. The purpose of IEPLC ([1]) is to mitigate the communication issues given by this heterogeneity; it proposes a framework to define communication interfaces in a hardware independent manner. In addition it automatically generates all the resources needed on master side (typically represented by a FEC: Front-End Computer) and slave side (typically represented by the controller) to implement a common and generic Ethernet communication. Th...

Locci, F

2014-01-01

341

Curved array photoacoustic tomographic system for small animal imaging  

PubMed Central

We present systematic characterization of a photoacoustic imaging system optimized for rapid, high-resolution tomographic imaging of small animals. The system is based on a 128-element ultrasonic transducer array with a 5-MHz center frequency and 80% bandwidth shaped to a quarter circle of 25 mm radius. A 16-channel data-acquisition module and dedicated channel detection electronics enable capture of a 90-deg field-of-view image in less than 1 s and a complete 360-deg scan using sample rotation within 15 s. Measurements on cylindrical phantom targets demonstrate a resolution of better than 200 ?m and high-sensitivity detection of 580-?m blood tubing to depths greater than 3 cm in a turbid medium with reduced scattering coefficient ?s?=7.8cm?1. The system is used to systematically investigate the effects of target size, orientation, and geometry on tomographic imaging. As a demonstration of these effects and the system imaging capabilities, we present tomographic photoacoustic images of the brain vasculature of an ex vivo mouse with varying measurement aperture. For the first time, according to our knowledge, resolution of sub-200-?m vessels with an overlying turbid medium of greater than 2 cm depth is demonstrated using only intrinsic biological contrast. PMID:18465970

Gamelin, John; Aguirre, Andres; Maurudis, Anastasios; Huang, Fei; Castillo, Diego; Wang, Lihong V.; Zhu, Quing

2008-01-01

342

A simple integrated system for electrophysiologic recordings in animals  

PubMed Central

This technical note describes a modification to a fundus camera that permits simultaneous recording of pattern electroretinograms (pERGs) and pattern visual evoked potentials (pVEPs). The modification consists of placing an organic light-emitting diode (OLED) in the split-viewer pathway of a fundus camera, in a plane conjugate to the subject’s pupil. In this way, a focused image of the OLED can be delivered to a precisely known location on the retina. The advantage of using an OLED is that it can achieve high luminance while maintaining high contrast, and with minimal degradation over time. This system is particularly useful for animal studies, especially when precise retinal positioning is required. PMID:19137347

Slater, Bernard J.; Miller, Neil R.; Bernstein, Steven L.; Flower, Robert W.

2009-01-01

343

Applications of a global small animal tracking system Songbird movements as an example  

E-print Network

biologists may find a global small-animal tracking system helpful in testing, validating and expanding181 Applications of a global small animal tracking system Songbird movements as an example Imagine, 1989). Queleas can migrate long distances, sometimes more Tracking animals over large temporal

Thorup, Kasper

344

The design of static and mobile HF communication systems  

NASA Astrophysics Data System (ADS)

The lecture deals with more specific aspects of HF communication system design arising from a previous lecture entitled HF system design principles presented as part of AGARD Lecture Series 127 in 1983. The major topics considered are: (1) the design of point-to-point systems; (2) the design of systems involving mobile terminals; (3) system control and frequency management; (4) resistance to interception and disruption. The lecture is intended to provide a technical framework for later lectures covering the more detailed aspects of HF communication system design.

Darnell, M.

1986-03-01

345

Circuit-aware system design techniques for wireless communication  

E-print Network

When designing wireless communication systems, many hardware details are hidden from the algorithm designer, especially with analog hardware. While it is difficult for a designer to understand all aspects of a complex ...

Huang, Everest W. (Everest Wang)

2006-01-01

346

An Asymmetric Stream Communication System Andrew P. Black  

E-print Network

An Asymmetric Stream Communication System Andrew P. Black Department of Computer Science, FR-35 construction at the University of Washington is radically different from this norm. In Eden it is quite usual

Black, Andrew P.

347

Personal communication system combines high performance with miniaturization  

NASA Technical Reports Server (NTRS)

Personal communication system provides miniaturized components that incorporate high level signal characteristics plus noise rejection in both microphone and earphone circuitry. The microphone is designed to overcome such spacecraft flight problems as size, ambient noise level, and RF interference.

Atlas, N. D.

1967-01-01

348

A Geometrical Study of Transmitted Reference Communication Systems  

Microsoft Academic Search

Digital communication systems utilizing wide-band carriers require a coherent reference for optimal data processing. This reference may be either locally generated or transmitted simultaneously with the data. The latter system completely avoids the synchronization problem of locally generated reference systems but is degraded by the fact that two receivers are required, excess system dimension must be used, and the transmitter

R. Gagliardi

1964-01-01

349

Cultural selection drives the evolution of human communication systems.  

PubMed

Human communication systems evolve culturally, but the evolutionary mechanisms that drive this evolution are not well understood. Against a baseline that communication variants spread in a population following neutral evolutionary dynamics (also known as drift models), we tested the role of two cultural selection models: coordination- and content-biased. We constructed a parametrized mixed probabilistic model of the spread of communicative variants in four 8-person laboratory micro-societies engaged in a simple communication game. We found that selectionist models, working in combination, explain the majority of the empirical data. The best-fitting parameter setting includes an egocentric bias and a content bias, suggesting that participants retained their own previously used communicative variants unless they encountered a superior (content-biased) variant, in which case it was adopted. This novel pattern of results suggests that (i) a theory of the cultural evolution of human communication systems must integrate selectionist models and (ii) human communication systems are functionally adaptive complex systems. PMID:24966310

Tamariz, Monica; Ellison, T Mark; Barr, Dale J; Fay, Nicolas

2014-08-01

350

Cultural selection drives the evolution of human communication systems  

PubMed Central

Human communication systems evolve culturally, but the evolutionary mechanisms that drive this evolution are not well understood. Against a baseline that communication variants spread in a population following neutral evolutionary dynamics (also known as drift models), we tested the role of two cultural selection models: coordination- and content-biased. We constructed a parametrized mixed probabilistic model of the spread of communicative variants in four 8-person laboratory micro-societies engaged in a simple communication game. We found that selectionist models, working in combination, explain the majority of the empirical data. The best-fitting parameter setting includes an egocentric bias and a content bias, suggesting that participants retained their own previously used communicative variants unless they encountered a superior (content-biased) variant, in which case it was adopted. This novel pattern of results suggests that (i) a theory of the cultural evolution of human communication systems must integrate selectionist models and (ii) human communication systems are functionally adaptive complex systems. PMID:24966310

Tamariz, Monica; Ellison, T. Mark; Barr, Dale J.; Fay, Nicolas

2014-01-01

351

Research of a portable atmospheric laser communication system  

NASA Astrophysics Data System (ADS)

A kind of portable atmosphere laser communication system based on fiber technology is designed by using Ethernet transceiver terminal and video-audio transceiver terminal with diode laser module and PIN diode, while a flexible connection is built between the terminal and the optical antenna connected by laser fiber. The application of EDFA technology, which realizes the amplification of the power of the 1550nm laser diode module, brings forth a more stable structure and easier deployment and testing in wild environment, and the communication distance can reach 2 kilometers with a transmission bandwidth of 100 MBit/s. Prototype experiments prove the good communication performance of this system.

Zeng, Wen-feng; Li, Dong; Li, Shen-peng; Tan, Wei; Yi, Zhigang

2013-08-01

352

Animation of multi-flexible body systems and its use in control system design  

NASA Technical Reports Server (NTRS)

Animation can greatly assist the structural dynamicist and control system analyst with better understanding of how multi-flexible body systems behave. For multi-flexible body systems, the structural characteristics (mode frequencies, mode shapes, and damping) change, sometimes dramatically with large angles of rotation between bodies. With computer animation, the analyst can visualize these changes and how the system responds to active control forces and torques. A characterization of the type of system we wish to animate is presented. The lack of clear understanding of the above effects was a key element leading to the development of a multi-flexible body animation software package. The resulting animation software is described in some detail here, followed by its application to the control system analyst. Other applications of this software can be determined on an individual need basis. A number of software products are currently available that make the high-speed rendering of rigid body mechanical system simulation possible. However, such options are not available for use in rendering flexible body mechanical system simulations. The desire for a high-speed flexible body visualization tool led to the development of the Flexible Or Rigid Mechanical System (FORMS) software. This software was developed at the Center for Simulation and Design Optimization of Mechanical Systems at the University of Iowa. FORMS provides interactive high-speed rendering of flexible and/or rigid body mechanical system simulations, and combines geometry and motion information to produce animated output. FORMS is designed to be both portable and flexible, and supports a number of different user interfaces and graphical display devices. Additional features have been added to FORMS that allow special visualization results related to the nature of the flexible body geometric representations.

Juengst, Carl; Stahlberg, Ron

1993-01-01

353

Hardware Implementation of Chaos-Secured Optical Communication Systems  

Microsoft Academic Search

\\u000a In the present chapter, the implementation and performance of contemporary chaotic optical communication systems is presented,\\u000a focusing on the physical layer encryption methods proposed so far. In communication systems that encrypt high-speed data within\\u000a broadband chaotic carriers, authorized users share identical chaotic oscillators that are capable – after synchronization\\u000a – of emitting exactly the same broadband chaotic optical signal. Several

Apostolos Argyris

354

Nonlinear filter based decision feedback equalizer for optical communication systems.  

PubMed

Nonlinear impairments in optical communication system have become a major concern of optical engineers. In this paper, we demonstrate that utilizing a nonlinear filter based Decision Feedback Equalizer (DFE) with error detection capability can deliver a better performance compared with the conventional linear filter based DFE. The proposed algorithms are tested in simulation using a coherent 100 Gb/sec 16-QAM optical communication system in a legacy optical network setting. PMID:24718240

Han, Xiaoqi; Cheng, Chi-Hao

2014-04-01

355

Domestic satellite communication system to be established in China  

NASA Astrophysics Data System (ADS)

The establishment of a domestic satellite communication system for China is discussed. To experiment, China built miniaturized ground stations and used the idle transponders of two INTELSAT satellites. The experiment was divided into three phases: verification and test of ground facilities; test of channel operations; and functional test of the Chinese built ground facilities. From a technical and economic point of view, developing China's domestic satellite communication system by leasing foreign satellites and building China's own ground stations is both efficient and effective.

Ruhou, Z.; Yucheng, B.

1984-01-01

356

Research of STBC in free space optical communications system  

NASA Astrophysics Data System (ADS)

Free Space Optical (FSO) communication is a communication pattern in which laser is used as the information carrier in atmosphere environment. FSO system has been widely applied in the fields of satellite communication and ground sight distance communication, with a promising application prospect and tremendous market potential. And space-time processing (using multiple antennas) is now recognized as a key to achieving reliable high data rate wireless communications and is being incorporated into the physical layer of many wireless standards. In this letter, error rate performance for space-time block coding (STBC) in FSO communication systems with direct detection operating over strong atmospheric turbulence channels is analyzed. The purpose of the paper is: (i) to determine the channel capacity of FSO system in the presence of atmospheric turbulence, (ii) to see how much this limit can be approached using the best known STBC techniques. In this paper, we use mathematics tool to establish the channel model of FSO system, and then apply the STBC to the FSO system, research the decoding method and simulate the performance using MATLAB tools. The mathematics analysis and simulation results show the great application expectation of STBC in the OOK channel of the FSO system.

Deng, Tianping; Peng, Kai; Lu, Yimin

2009-12-01

357

An all digital low data rate communication system  

NASA Technical Reports Server (NTRS)

The advent of digital hardwares has made it feasible to implement many communication system components digitally. With the exception of frequency down conversion, the proposed low data rate communication system uses digital hardwares completely. Although the system is designed primarily for deep space communications with large frequency uncertainty and low signal-to-noise ratio, it is also suitable for other low data rate applications with time-shared operation among a number of channels. Emphasis is placed on the fast Fourier transform receiver and the automatic frequency control via digital filtering. The speed available from the digital system allows sophisticated signal processing to reduce frequency uncertainty and to increase the signal-to-noise ratio. The practical limitations of the system such as the finite register length are examined. It is concluded that the proposed all-digital system is not only technically feasible but also has potential cost reduction over the existing receiving systems.

Chen, C.; Fan, M.

1973-01-01

358

An adaptive digital beamforming network for satellite communication systems  

NASA Astrophysics Data System (ADS)

The use of adaptive digital beamforming techniques has, until recently, been largely restricted to high performance military radar systems. Recent advances in digital technology, however, have enabled the design of single chip digital beamforming networks. This, coupled with advances in digital signal processor technology, enables complete beamforming systems to be constructed at a lower cost, thus making the application of these techniques to commercial communications systems attractive. The design and development of such an adaptative digital beamforming network are described. The system is being developed as a proof of concept laboratory based demonstrator to enable the feasibility of adaptive digital beamforming techniques for communication systems to be determined. Ultimately, digital beamforming could be used in conjunction with large array antennas for communication satellite systems. This will enable the simultaneous steering of high gain antenna beams in the direction of ground based users and the nulling of unwanted interference sources, such as radar systems, to be performed.

Barrett, M.; Fernandez, J.; Lagunas, M. A.; Coromina, F.

1991-10-01

359

A Study of Synchronization Techniques for Optical Communication Systems  

NASA Technical Reports Server (NTRS)

The study of synchronization techniques and related topics in the design of high data rate, deep space, optical communication systems was reported. Data cover: (1) effects of timing errors in narrow pulsed digital optical systems, (2) accuracy of microwave timing systems operating in low powered optical systems, (3) development of improved tracking systems for the optical channel and determination of their tracking performance, (4) development of usable photodetector mathematical models for application to analysis and performance design in communication receivers, and (5) study application of multi-level block encoding to optical transmission of digital data.

Gagliardi, R. M.

1975-01-01

360

Methods for operating parallel computing systems employing sequenced communications  

DOEpatents

A parallel computing system and method are disclosed having improved performance where a program is concurrently run on a plurality of nodes for reducing total processing time, each node having a processor, a memory, and a predetermined number of communication channels connected to the node and independently connected directly to other nodes. The present invention improves performance of the parallel computing system by providing a system which can provide efficient communication between the processors and between the system and input and output devices. A method is also disclosed which can locate defective nodes with the computing system. 15 figs.

Benner, R.E.; Gustafson, J.L.; Montry, G.R.

1999-08-10

361

Tunnel radio communications system at Stanford Linear Accelerator Center  

SciTech Connect

A unique single frequency, dual daisy chain tunnel radio communication system has been developed for use in our new Positron-Electron Storage Ring. Communications are possible between portables in the underground ring and between a portable in the ring and all control rooms on the site. The system is designed as a wide band facility and therefore can carry many simplex and duplex transmissions. This system utilizes TV twinlead as a distributed antenna and repeater amplifiers to cover more than 7000 feet of underground tunnel. The design philosophy, tests and initial design are discussed and contrasted with the final implementation of the system. Future uses of the system are discussed.

Struven, W.C.

1980-07-01

362

A systems engineering initiative for NASA's space communications  

NASA Technical Reports Server (NTRS)

In addition to but separate from the Red and Blue Teams commissioned by the NASA Administrator, NASA's Associate Administrator for Space Communications commissioned a Blue Team to review the Office of Space Communications (Code O) Core Program and determine how the program could be conducted faster, better, and cheaper, without compromising safety. Since there was no corresponding Red Team for the Code O Blue Team, the Blue Team assumed a Red Team independent attitude and challenged the status quo. The Blue Team process and results are summarized. The Associate Administrator for Space Communications subsequently convened a special management session to discuss the significance and implications of the Blue Team's report and to lay the groundwork and teamwork for the next steps, including the transition from engineering systems to systems engineering. The methodology and progress toward realizing the Code O Family vision and accomplishing the systems engineering initiative for NASA's space communications are presented.

Hornstein, Rhoda S.; Hei, Donald J., Jr.; Kelly, Angelita C.; Lightfoot, Patricia C.; Bell, Holland T.; Cureton-Snead, Izeller E.; Hurd, William J.; Scales, Charles H.

1993-01-01

363

5.8 GHz DSRC packet communication system for ITS services  

Microsoft Academic Search

In this paper, we introduce a 5.8 GHz DSRC (dedicated short range communication) packet communication system which has been developed by ETRI. 5.8 GHz DSRC packet communication systems are under deveolpment worldwide and it will be widely applied to ITS (intelligent transportation system) services. We discuss the basic requirements of the DSRC communication system and system design specification to meet

Hyunseo Oh; Chungil Yae; Donghyon Ahn; Hanberg Cho

1999-01-01

364

Integrated source and channel encoded digital communication system design study  

NASA Technical Reports Server (NTRS)

The particular Ku-band carrier, PN despreading, and symbol synchronization strategies, which were selected for implementation in the Ku-band transponder aboard the orbiter, were assessed and evaluated from a systems performance viewpoint, verifying that system specifications were met. A study was performed of the design and implementation of tracking techniques which are suitable for incorporation into the Orbiter Ku-band communication system. Emphasis was placed on maximizing tracking accuracy and communication system flexibility while minimizing cost, weight, and system complexity of Orbiter and ground systems hardware. The payload communication study assessed the design and performance of the forward link and return link bent-pipe relay modes for attached and detached payloads. As part of this study, a design for a forward link bent-pipe was proposed which employs a residual carrier but which is tracked by the existing Costas loop.

Alem, W. K.; Huth, G. K.; Simon, M. K.

1978-01-01

365

Development of A General Principle Solution Forisoagrinet Compliant Networking System Components in Animal Husbandry  

NASA Astrophysics Data System (ADS)

In pig production software and electronic systems are widely used for process control and management. Unfortunately most devices on farms are proprietary solutions and autonomically working. To unify data communication of devices in agricultural husbandry, the international standard ISOagriNET (ISO 17532:2007) was developed. It defines data formats and exchange protocols, to link up devices like climate controls, feeding systems and sensors, but also management software. The aim of the research project, "Information and Data Collection in Livestock Systems" is to develop an ISOagriNET compliant IT system, a so called Farming Cell. It integrates all electronic components to acquire the available data and information for pig fattening. That way, an additional benefit to humans, animals and the environment regarding process control and documentation, can be generated. Developing the Farming Cell is very complex; in detail it is very difficult and long-winded to integrate hardware and software by various vendors into an ISOagriNET compliant IT system. This ISOagriNET prototype shows as a test environment the potential of this new standard.

Kuhlmann, Arne; Herd, Daniel; Rö?ler, Benjamin; Gallmann, Eva; Jungbluth, Thomas

366

Simulation system architecture design for generic communications link  

NASA Technical Reports Server (NTRS)

This paper addresses a computer simulation system architecture design for generic digital communications systems. It addresses the issues of an overall system architecture in order to achieve a user-friendly, efficient, and yet easily implementable simulation system. The system block diagram and its individual functional components are described in detail. Software implementation is discussed with the VAX/VMS operating system used as a target environment.

Tsang, Chit-Sang; Ratliff, Jim

1986-01-01

367

Baseband system for human body channel communication  

Microsoft Academic Search

Biomedical sensor research is moving towards portable, wearable and implantable designs. Human body communication (HBC) is a promising data transmission method for low-power and high-speed biomedical sensors. Using the conductive human body as transmission medium, HBC trials has significant potential applications for personal healthcare and sports performance. The human body channel investigation identifies an optimum channel bandwidth of 1MHz to

Lin-hua Zhang; Xin-zhuo Liu; Jin Huang; Lei Wang

2010-01-01

368

Unmanned Aircraft Systems for Communication and Atmospheric Sensing Missions  

E-print Network

Unmanned Aircraft Systems for Communication and Atmospheric Sensing Missions Eric W. Frew, Brian and Engineer- ing Center for Unmanned Vehicles Heterogeneous Unmanned Aircraft System. The unmanned aircraft system is comprised of a fleet of small and miniature unmanned aircraft connected through a multi

Frew, Eric W.

369

New Automated Storage and Retrieval System (ASRS) using wireless communications  

Microsoft Academic Search

This study proposes a new design of an Automated Storage and Retrieval System (ASRS) using wireless communication. The highlight of this project is to aid and improve existing warehouse management system (WMS) that occupies manpower, on-paper data recording and non-intelligent machines during the operation. The essence of this project is to implement wireless technology in controlling ASRS system. Microcontroller and

M. M. Rashid; Banna Kasemi; Mahmudur Rahman

2011-01-01

370

Null steering beamforming for wireless communication system using genetic algorithm  

Microsoft Academic Search

Antenna array systems are important components of modern radar and wireless communication systems. By controlling the array through a real-time optimization process, the adaptive techniques diminish the impact of system component noise and mitigate the effects of interfering radiation to ensure the delivery of a maximum fidelity signal. This paper deals with the possibilities to cancel unwanted signals by steering

Vyacheslav Tuzlukov

2011-01-01

371

Remotely controlled communication and control system for limited mobility individuals  

Microsoft Academic Search

Design improvements to a remotely controlled system for patients with limited mobility are described. This system provides communication and control of the room environment with mouse control that can be adapted to the functional need of the user. Analysis is provided on the selection and integration of components within the system as well as an overview of the simulated access

Matthew Goldman; Ettore Cervo; Alexander Melle; Bryan Wilson; Seyitriza Tigrek; Frank Agyei-Ntim; Kimberly E. Newman; Frank Barnes; Michael Blei

2011-01-01

372

Group Communication in Partitionable Systems: Specification and Algorithms  

E-print Network

-5 An Expert System for the Evaluation of EDSS in Multiple Sclerosis, Gaspari, M., Roveda, G., Scandellari, C Locality Exploitation (PhD Thesis), D'Alberto, P., July 2000. 2000-10 System Support for Programming ObjectGroup Communication in Partitionable Systems: Specification and Algorithms ¨Ozalp Babaoglu Renzo

Montresor, Alberto

373

Systems analysis of the space shuttle. [communication systems, computer systems, and power distribution  

NASA Technical Reports Server (NTRS)

Developments in communications systems, computer systems, and power distribution systems for the space shuttle are described. The use of high speed delta modulation for bit rate compression in the transmission of television signals is discussed. Simultaneous Multiprocessor Organization, an approach to computer organization, is presented. Methods of computer simulation and automatic malfunction detection for the shuttle power distribution system are also described.

Schilling, D. L.; Oh, S. J.; Thau, F.

1975-01-01

374

Learning about Skeletons and Other Organ Systems of Vertebrate Animals.  

ERIC Educational Resources Information Center

Describes students' (n=175) understandings of the structure of animal (including human) skeletons and the internal organs found in them. Finds that older students have a better knowledge of animals' internal anatomies, although knowledge of human internal structure is significantly better than knowledge of rat, bird, and fish internal structure.…

Tunnicliffe, Sue Dale; Reiss, Michael

1999-01-01

375

RESEARCH OF ANIMAL DISEASE INFORMATION SYSTEM BASED ON GIS  

E-print Network

monitor and predict disease, as well as to support the disease prevention decision making, in order and FMD diseases as well as other kind of animal diseases have caused disastrous result by disease-occurring disease with regional feature, and the animal husbandry and veterinary health institutions are all closely

Boyer, Edmond

376

Eavesdropping and communication networks revealed through playback and an acoustic location system  

Microsoft Academic Search

Our understanding of animal communication is expanding from a dyadic framework of one signaler and one receiver to a broader communication network model, yet empirical studies of communication networks are scarce. To investigate whether territorial males eavesdrop on interactions occurring outside of their territory boundaries and to quantify the neighborhood-level effects of song contests, we simulated diurnal dyadic countersinging exchanges

Lauren P. Fitzsimmons; Jennifer R. Foote; Laurene M. Ratcliffe; Daniel J. Mennill

2008-01-01

377

Conceptual design of a communications system for Mars exploration missions  

NASA Technical Reports Server (NTRS)

Future missions to Mars will require a communications system to link activities on the Martian surface with each other and with mission controllers on earth. This paper documents the preliminary design of an areosynchronous communications satellite to provide such links. As designed, the satellite will provide almost continuous communication between Mars and earth, as well as continuous Mars surface-to-surface links. The capacity will exist for voice, data/command, and video transmission. The mission scenario assumed for this design is described, followed by the configuration design. The communications systems conceptual design and its impact on the overall spacecraft requirements are then presented. Supporting subsystems including electrical power; thermal control; guidance, navigation, and control; propulsion; structures; and configuration are reviewed. A description of the operating orbit and the assumed method of orbit acquisition are discussed.

Badi, Deborah M.; Farmer, Jeffery T.; Martin, Gary L.; Garn, Paul A.

1989-01-01

378

MLCD: Overview of NASA's Mars Laser Communications Demonstration System  

Microsoft Academic Search

NASA is presently overseeing a project to create the world's first free-space laser communications system that can be operated over a range much larger than the near-earth ranges that have been demonstrated to date. To be flown on the Mars Telecom Orbiter, planned for launch by NASA in 2009, it will demonstrate high-rate laser communications from Mars orbit to one

D. M. Boroson; A. Biswas; B. L. Edwards

379

On Adaptive Communication in Asynchronous Real-Time Distributed Systems  

Microsoft Academic Search

We present adaptive communication heuristic algorithms for periodic tasks in asynchronous real-time distributed systems. The heuristic algorithms adapt the application to workload changes through trans-node message-level adaptation mechanisms. We present adaptive communication heuristics for IEEE 802.5 token ring networks that support the priority- driven protocol and for FDDI networks that use the Timed Token protocol. The heuristic algorithms adapt periodic

Binoy Ravindran; Baoping Zhang

2001-01-01

380

Optimal design of sequential real-time communication systems  

Microsoft Academic Search

Optimal design of sequential real-time communication of a Markov source over a noisy channel is investigated. In such a system, the delay between the source output and its reconstruction at the receiver should equal a fixed prespecified amount. An optimal communication strategy must minimize the total expected symbol-by-symbol distortion between the source output and its reconstruction. Design techniques or performance

Aditya Mahajan; Demosthenis Teneketzis

2009-01-01

381

An isolated working heart system for large animal models.  

PubMed

Since its introduction in the late 19(th) century, the Langendorff isolated heart perfusion apparatus, and the subsequent development of the working heart model, have been invaluable tools for studying cardiovascular function and disease(1-15). Although the Langendorff heart preparation can be used for any mammalian heart, most studies involving this apparatus use small animal models (e.g., mouse, rat, and rabbit) due to the increased complexity of systems for larger mammals(1,3,11). One major difficulty is ensuring a constant coronary perfusion pressure over a range of different heart sizes - a key component of any experiment utilizing this device(1,11). By replacing the classic hydrostatic afterload column with a centrifugal pump, the Langendorff working heart apparatus described below allows for easy adjustment and tight regulation of perfusion pressures, meaning the same set-up can be used for various species or heart sizes. Furthermore, this configuration can also seamlessly switch between constant pressure or constant flow during reperfusion, depending on the user's preferences. The open nature of this setup, despite making temperature regulation more difficult than other designs, allows for easy collection of effluent and ventricular pressure-volume data. PMID:24962492

Schechter, Matthew A; Southerland, Kevin W; Feger, Bryan J; Linder, Dean; Ali, Ayyaz A; Njoroge, Linda; Milano, Carmelo A; Bowles, Dawn E

2014-01-01

382

Automatic real-time pair-feeding system for animals  

NASA Technical Reports Server (NTRS)

A pair feeding method and apparatus are provided for experimental animals wherein the amount of food consumed is immediately delivered to a normal or control animal so that there is a qualitative, quantitative and chronological correctness in the pair feeding of the two animals. This feeding mechanism delivers precisely measured amounts of food to a feeder. Circuitry is provided between master and slave feeders so that there is virtually no chance of a malfunction of the feeding apparatus, causing erratic results. Recording equipment is also provided so that an hourly record is kept of food delivery.

Leon, H. A.; Connolly, J. P.; Hitchman, M. J.; Humbert, J. E. (inventors)

1974-01-01

383

Computer-aided communication satellite system analysis and optimization  

NASA Technical Reports Server (NTRS)

The capabilities and limitations of the various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. A satellite Telecommunication analysis and Modeling Program (STAMP) for costing and sensitivity analysis work in application of communication satellites to educational development is given. The modifications made to STAMP include: extension of the six beam capability to eight; addition of generation of multiple beams from a single reflector system with an array of feeds; an improved system costing to reflect the time value of money, growth in earth terminal population with time, and to account for various measures of system reliability; inclusion of a model for scintillation at microwave frequencies in the communication link loss model; and, an updated technological environment.

Stagl, T. W.; Morgan, N. H.; Morley, R. E.; Singh, J. P.

1973-01-01

384

Communications satellite systems operations with the space station, volume 2  

NASA Technical Reports Server (NTRS)

A financial model was developed which described quantitatively the economics of the space segment of communication satellite systems. The model describes the economics of the space system throughout the lifetime of the satellite. The expected state-of-the-art status of communications satellite systems and operations beginning service in 1995 were assessed and described. New or enhanced space-based activities and associated satellite system designs that have the potential to achieve future communications satellite operations in geostationary orbit with improved economic performance were postulated and defined. Three scenarios using combinations of space-based activities were analyzed: a spin stabilized satellite, a three axis satellite, and assembly at the Space Station and GEO servicing. Functional and technical requirements placed on the Space Station by the scenarios were detailed. Requirements on the satellite were also listed.

Price, K.; Dixon, J.; Weyandt, C.

1987-01-01

385

Systems for Anonymous Communication George Danezis  

E-print Network

: semi- trusted relays, mix systems, remailers, robust & verifiable mixes, and onion routing systems. We.2 Provable security for mix-networks . . . . . . . . . . . . . . . . . 30 5 Onion routing 32 5.1 Early onion routing systems . . . . . . . . . . . . . . . . . . . . . 32 5.2 Tor's Onion Routing

Syverson, Paul

386

Improving Literacy Skills in Students with Complex Communication Needs Who Use Augmentative/Alternative Communication Systems  

ERIC Educational Resources Information Center

A structured intervention package including direct, scaffolded, instructional lessons was implemented using an error correction learning system and a picture book-based phonological and phonemic awareness activity for four participants with complex communication needs, ranging from 12 to 15 years, in a junior high school setting. Although…

Bailey, Rita L.; Angell, Maureen E.; Stoner, Julia B.

2011-01-01

387

Short communication: renal tubular vacuolation in animals treated with polyethylene-glycol-conjugated proteins.  

PubMed

During toxicologic evaluation of a dimeric PEG-linked protein, tumor necrosis factor binding protein (TNF-bp), vacuolation of renal cortical tubular epithelium was seen in male and female Sprague-Dawley rats (200-300 g) given i.v. doses of 40, 20, or 10 mg/kg every other day for 3 months. Tubular lesions in rats treated with 20 or 40 mg/kg for 3 months were only partially reversible after a 2-month recovery period. Despite the presence of marked vacuolation, there were no changes in BUN, creatinine, urinalysis parameters, urinary NAG, urinary B2-microglobulin, or fractional sodium excretion. Single i.v. doses > or = 20 mg/kg TNF-bp caused similar but milder changes. However, equivalent doses of PEG alone or the non-PEG-linked TNF-bp did not cause light microscopic evidence of vacuolation. Treatment of rats with another PEG-linked protein of similar molecular weight resulted in similar changes. Immunostaining for TNF-bp revealed positivity in the apical cytoplasm of renal tubular epithelium within 1 h of i.v. dosing. Immunostaining of kidneys from chronically dosed rats indicated that protein was present in some vacuoles as long as dosing continued; however, kidneys from animals on a reversibility study had vacuoles but no immunostaining for TNF-bp. These results, along with a study that showed more severe lesions with PEG-linked proteins of lower molecular weight and minimal if any lesions with PEG-linked proteins > 70 kDa, suggest that TNF-bp is filtered through the glomerulus and that the protein with attached PEG is reabsorbed by the proximal tubules. Vacuolation may be a result of fluid distension of lysosomes due to the hygroscopic nature of PEG. These studies demonstrated that PEG-linked proteins have the capacity to induce renal tubular vacuolation at high doses. However, the change was not associated with alteration of clinical pathology or functional markers. PMID:9579027

Bendele, A; Seely, J; Richey, C; Sennello, G; Shopp, G

1998-04-01

388

THz channel characterization for future wireless gigabit indoor communication systems  

NASA Astrophysics Data System (ADS)

Short range wireless communication systems are expanding at rapid rate, finding application in offices, congested urban areas and homes. Development of wireless local area networks is accompanied by a steady increase in the demand for ever higher data rates. This in turn entails the necessity to develop communication systems which operate at higher frequencies. Currently WLAN works at a few GHz, while systems operating at several ten GHz appear already feasible. It can be expected that wireless short-range communication networks will soon push towards the THz frequency range and that systems which handle high-density information and support wider bandwidth communications will be developed in a few years time. Since THz radiation is strongly absorbed by the atmosphere, working distances may be short and individual THz pico-cells may cover only single rooms or at most one building. For an indoor system of practical importance it must be robust against shadowing. Recently, flexible all-plastic mirrors, supporting specular reflections in the THz range have been demonstrated. They are cheap and easy to produce and can be used as frequency selective wall-paper to enhance the reflectivity of walls and hence facilitate non-line-of-sight communication in a THz cell. For this case the spatial and temporal characteristics of the indoor THz propagation channel in a room with randomly placed objects and moving people are derived with ray-tracing methodology and Monte Carlo simulations. Our simulations show that high-gain antennas will be needed for the realization of THz communication in indoor environments. Furthermore, indirect transmission paths between transmitter and receiver, supported by dielectric mirrors make the communication channel much more robust against shadowing.

Piesiewicz, Radoslaw; Jemai, Jaouhar; Koch, Martin; Kurner, Thomas

2005-03-01

389

Communications system for zero-g simulation tests in water  

NASA Technical Reports Server (NTRS)

System connects seven observers, diver, and spare station, and utilizes public address system with underwater speakers to provide two-way communications between test subject and personnel in control of life support, so that test personnel are warned immediately of malfunction in pressure suit or equipment.

Smith, H. E.

1971-01-01

390

Floating avatar: telepresence system using blimps for communication and entertainment  

Microsoft Academic Search

We developed a floating avatar system that integrates a blimp with a virtual avatar to create a unique telepresence system. Our blimp works as an avatar and contains several pieces of equipment, including a projector and a speaker as the output functions. Users can communicate with others by transmitting their facial image through the projector and voice through the speaker.

Hiroaki Tobita; Shigeaki Maruyama; Takuya Kuzi

2011-01-01

391

Analysis of submarine cable and communication satellite systems reliabilities  

Microsoft Academic Search

The performance of AT&T's overseas message telephone circuits for the years 1970-1975 was the basis for ana analysis of the reliability of submarine cables and communication satellite systems. Data presented in 24 tables is devided into three categories: (1) over cable and satellite system outage statistics for each of the six years and the six year average, (2) detailed cable

G. S. Li

1977-01-01

392

Communications diversity advantages for the Mobile User Objective System  

Microsoft Academic Search

The UHF radio frequency (RF) band available for the our future military Mobile User Objective System (MUOS) satellite communications system has to contend with the signal scintillation effects encountered from propagation through the ionosphere as well as multipath signals from terrestrial signal reflections that will be prominent with new handheld terminals. These effects cause signal fading which can severely degrade

Per A. Kullstam

2000-01-01

393

DMA-Assisted, Intranode Communication in GPU Accelerated Systems  

E-print Network

DMA-Assisted, Intranode Communication in GPU Accelerated Systems Feng Ji, Ashwin M. Aji, James Abstract--Accelerator-awareness has become a pressing issue in data movement models, such as MPI, due to the rapid deployment of systems that utilize accelerators. In our previous work, we developed techniques

Ma, Xiaosong

394

On performance bounds for MIMO OFDM based wireless communication systems  

Microsoft Academic Search

In this paper, we develop several increasingly tight and restrictive performance bounds for OFDM based MIMO wireless communication systems. Starting with channel capacity as the ultimate upper bound on the throughput, step by step we develop tighter bounds on the practically achievable throughput by incorporating typical design constraints. The presented bounds are applied to a Long Term Evolution system, allowing

Stefan Schwarz; Michal Simko; Markus Rupp

2011-01-01

395

Globally Optimal Transmitter Placement for Indoor Wireless Communication Systems  

E-print Network

Globally Optimal Transmitter Placement for Indoor Wireless Communication Systems J. He, A. Verstak is applied to solve the optimal transmitter placement problem for indoor wireless systems. An eĂ?cient pattern search algorithm|DIRECT (DIviding RECTangles) of Jones, Perttunen, and Stuckman (1993)| has been

Neumaier, Arnold

396

A queuing model for meteor burst packet communication systems  

Microsoft Academic Search

A discrete-time queuing model for the performance of a meteor-burst packet communication system is analyzed using matrix analytic methods. Not only is the system subject to interruptions due to the intermittence of the ionization layer, but its analysis is further complicated by the necessity to retransmit packets that have error or that occur at the tail end of a period

Y. Chandramouli; M. F. Neuts; V. Ramaswami

1989-01-01

397

Kansas Communication and Instruction System through Fiber-Optic Transmission.  

ERIC Educational Resources Information Center

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…

Kansas State Dept. of Education, Topeka.

398

A control and communication system for natural gas in Sweden  

SciTech Connect

In order to handle a gassystem is it important that the informations about the different situations in the system are reliable and easy to understand. This paper presents the control and communication system in order to handle the high pressure gasgrid in Sweden.

Widing, N.

1988-01-01

399

Spread spectrum synchronization for a LEO personal communications satellite system  

Microsoft Academic Search

This paper investigates required signal structure and receiver code synchronization techniques for satellite based CDMA personal communications systems. A signal structure is proposed in which different CDMA codes are used to differentiate each satellite (as in the GPS system) and different phases of one code (as in the IS-95 standard) to differentiate spot beams on one satellite. Due to satellite

D. E. Dodds; M. Moher

1995-01-01

400

Computer-Aided Communication Satellite System Analysis and Optimization.  

ERIC Educational Resources Information Center

Various published computer programs for fixed/broadcast communication satellite system synthesis and optimization are discussed. The rationale for selecting General Dynamics/Convair's Satellite Telecommunication Analysis and Modeling Program (STAMP) in modified form to aid in the system costing and sensitivity analysis work in the Program on…

Stagl, Thomas W.; And Others

401

Underground Mine Communication and Tracking Systems : A Survey  

E-print Network

Underground Mine Communication and Tracking Systems : A Survey Prasant Misra1 Diet Ostry2 Sanjay;Abstract This article presents a survey of the state-of-the art underground mine com- munication and tracking systems. Underground mines are extensive labyrinths. They employ hundreds of mining personnel

New South Wales, University of

402

Channel simulation for direct-detection optical communication systems  

NASA Technical Reports Server (NTRS)

A technique is described for simulating the random modulation imposed by atmospheric scintillation and transmitter pointing jitter on a direct-detection optical communication system. The system is capable of providing signal fading statistics which obey log-normal, beta, Rayleigh, Ricean, or chi-square density functions. Experimental tests of the performance of the channel simulator are presented.

Tycz, M.; Fitzmaurice, M. W.

1974-01-01

403

An overview of limited feedback in wireless communication systems  

Microsoft Academic Search

It is now well known that employing channel adaptive signaling in wireless communication systems can yield large improvements in almost any performance metric. Unfortunately, many kinds of channel adaptive techniques have been deemed impractical in the past because of the problem of obtaining channel knowledge at the transmitter. The transmitter in many systems (such as those using frequency division duplexing)

David James Love; Robert W. Heath Jr.; Vincent K. N. Lau; David Gesbert; Bhaskar D. Rao; Matthew Andrews

2008-01-01

404

Short communication Hedgehog structure in nematic and magnetic systems  

E-print Network

1097 Short communication Hedgehog structure in nematic and magnetic systems N. Schopohl and T structure of hedgehog point disclinations in magnetic and nematic liquid crystal systems is investigated. In the nematic hedgehog the solution is uniaxial everywhere. Nematic hedgehogs are very much larger than magnetic

Paris-Sud XI, Université de

405

An Evaluation of the Amoeba Group Communication System  

Microsoft Academic Search

The Amoeba group communication system has two unique aspects: (1) it uses a sequencer-based protocol with negative acknowledgements for achieving a total order on all group messages; and (2) users choose the degree of fault tolerance they desire. This paper reports on our design de- cisions in retrospect, the performance of the Amoeba group system, and our experiences using the

M. Frans Kaashoek; Andrew S. Tanenbaum

1996-01-01

406

Unmanned Aircraft System Control and ATC Communications Bandwidth Requirements  

NASA Technical Reports Server (NTRS)

There are significant activities taking place to establish the procedures and requirements for safe and routine operation of unmanned aircraft systems (UAS) in the National Airspace System (NAS). Among the barriers to overcome in achieving this goal is the lack of sufficient frequency spectrum necessary for the UAS control and air traffic control (ATC) communications links. This shortcoming is compounded by the fact that the UAS control communications links will likely be required to operate in protected frequency spectrum, just as ATC communications links are, because they relate to "safety and regularity of flight." To support future International Telecommunications Union (ITU) World Radio Conference (WRC) agenda items concerning new frequency allocations for UAS communications links, and to augment the Future Communications Study (FCS) Technology Evaluation Group efforts, NASA Glenn Research Center has sponsored a task to estimate the UAS control and ATC communications bandwidth requirements for safe, reliable, and routine operation of UAS in the NAS. This report describes the process and results of that task. The study focused on long-term bandwidth requirements for UAS approximately through 2030.

Henriksen, Steve

2008-01-01

407

Advanced information processing system: Authentication protocols for network communication  

NASA Technical Reports Server (NTRS)

In safety critical I/O and intercomputer communication networks, reliable message transmission is an important concern. Difficulties of communication and fault identification in networks arise primarily because the sender of a transmission cannot be identified with certainty, an intermediate node can corrupt a message without certainty of detection, and a babbling node cannot be identified and silenced without lengthy diagnosis and reconfiguration . Authentication protocols use digital signature techniques to verify the authenticity of messages with high probability. Such protocols appear to provide an efficient solution to many of these problems. The objective of this program is to develop, demonstrate, and evaluate intercomputer communication architectures which employ authentication. As a context for the evaluation, the authentication protocol-based communication concept was demonstrated under this program by hosting a real-time flight critical guidance, navigation and control algorithm on a distributed, heterogeneous, mixed redundancy system of workstations and embedded fault-tolerant computers.

Harper, Richard E.; Adams, Stuart J.; Babikyan, Carol A.; Butler, Bryan P.; Clark, Anne L.; Lala, Jaynarayan H.

1994-01-01

408

Fast massive preventive security and information communication systems  

NASA Astrophysics Data System (ADS)

We present a fast massive information communication system for data collection from distributive sources such as cell phone users. As a very important application one can mention preventive notification systems when timely notification and evidence communication may help to improve safety and security through wide public involvement by ensuring easy-to-access and easy-to-communicate information systems. The technology significantly simplifies the response to the events and will help e.g. special agencies to gather crucial information in time and respond as quickly as possible. Cellular phones are nowadays affordable for most of the residents and became a common personal accessory. The paper describes several ways to design such systems including existing internet access capabilities of cell phones or downloadable specialized software. We provide examples of such designs. The main idea is in structuring information in predetermined way and communicating data through a centralized gate-server which will automatically process information and forward it to a proper destination. The gate-server eliminates a need in knowing contact data and specific local community infrastructure. All the cell phones will have self-localizing capability according to FCC E911 mandate, thus the communicated information can be further tagged automatically by location and time information.

Akopian, David; Chen, Philip; Miryakar, Susheel; Kumar, Abhinav

2008-04-01

409

Communicating with Virtual Humans.  

ERIC Educational Resources Information Center

The face is a small part of a human, but it plays an essential role in communication. An open hybrid system for facial animation is presented. It encapsulates a considerable amount of information regarding facial models, movements, expressions, emotions, and speech. The complex description of facial animation can be handled better by assigning…

Thalmann, Nadia Magnenat

410

Adaptive MIMO transmission techniques for broadband wireless communication systems [Topics in Wireless Communications  

Microsoft Academic Search

Link adaptation is a way to increase data rates in wireless systems by adapting transmission parameters such as the modulation and coding rate. While link adaptation in single antenna systems is now mature, its application to multiple-input multiple-output communication links, presented in several emerging wireless standards, has been challenging. The main reason is that the space-time transmission strategy can also

Chan-Byoung Chae; Alcatel-Lucent Antonio Forenza; Matthew R. McKay; Iain B. Collings

2010-01-01

411

Potential markets for a satellite-based mobile communications system  

NASA Technical Reports Server (NTRS)

The objective of the study was to define the market needs for improved land mobile communications systems. Within the context of this objective, the following goals were set: (1) characterize the present mobile communications industry; (2) determine the market for an improved system for mobile communications; and (3) define the system requirements as seen from the potential customer's viewpoint. The scope of the study was defined by the following parameters: (1) markets were confined to U.S. and Canada; (2) range of operation generally exceeded 20 miles, but this was not restrictive; (3) the classes of potential users considered included all private sector users, and non-military public sector users; (4) the time span examined was 1975 to 1985; and (5) highly localized users were generally excluded - e.g., taxicabs, and local paging.

Jamieson, W. M.; Peet, C. S.; Bengston, R. J.

1976-01-01

412

Specification for installation of the crew activity planning system coaxial cable communication system  

NASA Technical Reports Server (NTRS)

The specification used to install a broadband coaxial cable communication system to support remote terminal operations on the Crew Activity Planning system at the Lyndon B. Johnson Space Center are reported. The system supports high speed communications between a Harris Slash 8 computer and one or more Sanders Graphic 7 displays.

Allen, M. A.; Roman, G. S.

1979-01-01

413

Performance evaluation of ?\\/4 DQPSK wireless communication system with direct-conversion  

Microsoft Academic Search

Recently, there has been a shift from analog to digital wireless communication systems among those used for wireless communication systems. Promotion of the digitization of wireless communication systems has drawn attention to direct-conversion (DC) receivers as means of reducing the cost of digital wireless communication equipment. In this paper, we propose an algorithm for estimating and compensating for Carrier Frequency

Yuji Yokota; Takuro Yoshida; Daisuke Nojima; Yuhei Nagao; Masayuki Kurosaki; Hiroshi Ochi

2012-01-01

414

Synchronization of system-of-systems interfaces in military satellite communications  

E-print Network

Military systems continue to become more complex and nearly all are now part of one or more system of systems (SoS). Military satellite communications programs have expanded over the last decade from three distinct satellite ...

Davis, Mark J. (Mark Jeffrey)

2008-01-01

415

Low level communication management for e-health systems  

NASA Astrophysics Data System (ADS)

The heterogeneity of e-health systems encourages the use of standards such as Health Level 7 (HL7v3) to ensure interoperability. Many actual implementations address this problem by unoptimized high level programming of top-range portable computing platforms. However, this approach could pose excessive demands on battery-powered mid-range terminals. In this work, we propose low-level support for portable HL7v3-compatible embedded systems in order to better exploit their limited processing and communications capabilities. In particular, we present our experience in mobile communication management through two different approaches, which proves the feasibility of this proposal.

Riva, Guillermo; Zerbini, Carlos; Voos, Javier; Centeno, Carlos; González, Eduardo

2011-12-01

416

ROBUS-2: A Fault-Tolerant Broadcast Communication System  

NASA Technical Reports Server (NTRS)

The Reliable Optical Bus (ROBUS) is the core communication system of the Scalable Processor-Independent Design for Enhanced Reliability (SPIDER), a general-purpose fault-tolerant integrated modular architecture currently under development at NASA Langley Research Center. The ROBUS is a time-division multiple access (TDMA) broadcast communication system with medium access control by means of time-indexed communication schedule. ROBUS-2 is a developmental version of the ROBUS providing guaranteed fault-tolerant services to the attached processing elements (PEs), in the presence of a bounded number of faults. These services include message broadcast (Byzantine Agreement), dynamic communication schedule update, clock synchronization, and distributed diagnosis (group membership). The ROBUS also features fault-tolerant startup and restart capabilities. ROBUS-2 is tolerant to internal as well as PE faults, and incorporates a dynamic self-reconfiguration capability driven by the internal diagnostic system. This version of the ROBUS is intended for laboratory experimentation and demonstrations of the capability to reintegrate failed nodes, dynamically update the communication schedule, and tolerate and recover from correlated transient faults.

Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Miner, Paul S.

2005-01-01

417

Experimental millimeter-wave personal satellite communications system  

NASA Technical Reports Server (NTRS)

Communications Research Laboratory (CRL) has investigated an advanced millimeter (mm)-wave satellite communications system for personal use. Experiments in mm-wave personal satellite communication are to be conducted for 3 years using Japan's Engineering Test Satellite VI (ETS-VI). This paper describes an experimental mm-wave (43/38 GHz) personal satellite communication system, including an onboard transponder and an earth terminal. The on-board transponder is almost completed, and the ground experiment system is still in the design stage. The transponder employs advanced mm-wave solid state technology. It uses 38 GHz high power solid state amplifiers to accelerate the development of mm-wave solid state devices which are indispensable to personal earth terminals. The transponder consists of a 43 GHz receiver with a built-in low noise amplifier, an IF filter section with very narrow bandwidth to improve the carrier-to-noise power ratio of the weak personal communication signal, and two high power amplifiers using newly developed high power Gallium Arsenide (GaAs) metal-semiconductor field effect transistors (MESFETs).

Suzuki, Yoshiaki; Kimura, Shigeru; Shimada, Masaaki; Tanaka, Masato; Takahashi, Yasuhiro

1991-01-01

418

Reactive system verification case study: Fault-tolerant transputer communication  

NASA Technical Reports Server (NTRS)

A reactive program is one which engages in an ongoing interaction with its environment. A system which is controlled by an embedded reactive program is called a reactive system. Examples of reactive systems are aircraft flight management systems, bank automatic teller machine (ATM) networks, airline reservation systems, and computer operating systems. Reactive systems are often naturally modeled (for logical design purposes) as a composition of autonomous processes which progress concurrently and which communicate to share information and/or to coordinate activities. Formal (i.e., mathematical) frameworks for system verification are tools used to increase the users' confidence that a system design satisfies its specification. A framework for reactive system verification includes formal languages for system modeling and for behavior specification and decision procedures and/or proof-systems for verifying that the system model satisfies the system specifications. Using the Ostroff framework for reactive system verification, an approach to achieving fault-tolerant communication between transputers was shown to be effective. The key components of the design, the decoupler processes, may be viewed as discrete-event-controllers introduced to constrain system behavior such that system specifications are satisfied. The Ostroff framework was also effective. The expressiveness of the modeling language permitted construction of a faithful model of the transputer network. The relevant specifications were readily expressed in the specification language. The set of decision procedures provided was adequate to verify the specifications of interest. The need for improved support for system behavior visualization is emphasized.

Crane, D. Francis; Hamory, Philip J.

1993-01-01

419

Laser communication terminals for the European Data Relay System  

NASA Astrophysics Data System (ADS)

For the first time, laser communication terminals will be operational in a commercial service, EDRS, the European Data Relay System. Future earth observation satellites call for satellite-to-ground links with high availability to make their data immediately available to the user. High availability is only achieved by GEO relay links, i.e. communication links from LEO satellites to a geostationary relay satellite which transmits the data to the ground. While RF communication limits the GEO relay's data rate to roughly 1 Gbps optical communication will extend its capacity into the 10 Gbps range. Today, laser communication terminals operated in LEO-LEO, LEO-to ground and ground-to-LEO links, all at a data rate of 5.625 Gbps, are applied in campaigns with scientific objectives and for technology demonstrating purposes. Adapted to the larger link distance of the LEO-to-GEO link the laser communication terminals will be applied in the GEO relay EDRS operated for the time being at 1.8 Gbps. Terminals will be delivered for the accommodation on Alphabus, EDRS-A and EDRS-C, European GEO-satellites, and on Sentinel-1a and Sentinel-2a, European LEO satellites.

Böhmer, Knut; Gregory, Mark; Heine, Frank; Kämpfner, Hartmut; Lange, Robert; Lutzer, Michael; Meyer, Rolf

2012-02-01

420

47 CFR 4.13 - Reports by the National Communications System (NCS) and by special offices and facilities, and...  

Code of Federal Regulations, 2010 CFR

...false Reports by the National Communications System (NCS) and by special...related responsibilities of communications providers. 4.13 Section...Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL...

2010-10-01

421

A general analysis of anti-jam communication systems  

NASA Technical Reports Server (NTRS)

A general error bound is derived for a general anti-jam communication system which will serve as the basis for evaluating the performance of all such complex communication systems. The two most common spread spectrum techniques, coherent DS/BPSK and noncoherent FH/MFSK, are analyzed. Pulse jamming represents the worst type of jammer for DS/BPSK systems, and several receiver structures against such a jammer are examined. It is found that for low values of chip energy-to-noise ratios of O dB or less there is little difference between having or not having jammer state knowledge with a hard decision receiver. Soft decision receivers are shown to be useless against very narrow pulses without jammer state knowledge. Partial band jammers are close to the worst case jammer for FH/MFSK systems. The conclusions found for these systems are similar to those for the DS/BPSK systems.

Omura, J. K.; Levitt, B. K.

1981-01-01

422

A nuclear radiation detector system with integrated readout for SPECT\\/MR small animal imaging  

Microsoft Academic Search

We have developed and constructed an MR-compatible single photon emission computed tomography (SPECT) system for small animal molecular imaging applications. The system consists of identical radiation imaging modules and a multi-pinhole collimator sleeve. The modular design results in a very compact system which allows for easy insertion into state-of-the-art small animal MRI systems. This development leads to a multi-modality system

Suleyman Azman; J. Gjaerum; D. Meier; L. T. Muftuler; G. Maehlum; O. Nalcioglu; B. E. Patt; B. Sundal; M. Szawlowski; B. M. W. Tsui; D. J. Wagenaar; Yuchuang Wang

2007-01-01

423

Low-power FLC-based retromodulator communications system  

NASA Astrophysics Data System (ADS)

On September 15, 1996, researchers from Utah State University/Space Dynamics Lab in conjunction with Phillips Lab/Starfire Optical Range and Kjome Research successfully flew and tested a retromodulator laser communication package on a high altitude balloon. This paper addresses the layout and hardware used for the communication link, as well as presenting some preliminary data collected during the 6 hour flight of the balloon. The package was a proof of concept demonstration system for a low-power laser communications systems for small, low Earth orbiting satellites. The ferroelectric liquid crystal based retromodulator design of Utah State provided test patterns for modulation rates up to 20 kilo bits per second. Data was successfully downlinked using a 1200 bps RS232 format and a simplistic receiver. The Starfire Optical Range 1.5-meter telescope located on Kirtland AFB, tracked the balloon, which reached a float altitude of 31 km and collected the modulated light reflected from the payload.

Swenson, Charles M.; Steed, Clark A.; de La Rue, Imelda A.; Fugate, Robert Q.

1997-05-01

424

Plastic optical fiber serial communications link for distributed control system  

NASA Astrophysics Data System (ADS)

One of the most common interface for communications specified is RS 232C standard. Though widely accepted, RS232 has limited transmission speed, range and networking capabilities. RS 422 standard overcomes limitations by using differential signal lines. In automation of the operation of gas discharge lasers, multiple processors are used for control of lasers, cooling system, vacuum system etc. High EMI generated by lasers interfere through galvanic transmission or by radiation over the length of cables, and hang up operation of processors or control PC. A serial communications link was designed eliminating copper transmission media, using plastic optical fiber cables and components, to connect local controllers with the master PC working on RS232 protocols. The paper discusses the design and implementation of a high ly reliable EMI harden serial communications link.

Saxena, Piyush; Sharangpani, K. K.; Vora, H. S.; Nakhe, S. V.; Jain, R.; Shenoy, N. M.; Bhatnagar, R.; Shirke, N. D.

2001-09-01

425

Pupa: A Low-Latency Communication System for Fast Ethernet  

Microsoft Academic Search

Pupa is a low-latency communication system that provides the same quality of message delivery as TCP butis designed specifically for a parallel computing cluster connected by a 100 Mbits\\/sec Fast Ethernet. Theimplementation has been operational for over a year, and several systems have been built on top of Pupa,including a compiler-directed distributed shared virtual memory system, Locust , and a

Manish Verma

1998-01-01

426

Performance analysis of multi-user UWB wireless communication systems  

Microsoft Academic Search

This paper presents a performance comparison of impulse radio ultra wideband (IR-UWB) and multi-band orthogonal frequency division multiplexing (MB-OFDM) for multi-user wireless communication systems. Focusing on the analysis of system performance affected by multi-user interference (MUI) over general additive white Gaussion noise (AWGN) channel, we run a complete system simulation for direct sequence pulse amplitude modulation (DS-PAM), time hopping pulse

Yuhong Li; Youzheng Wang; Jianhua Lu

2009-01-01

427

Object Oriented Vertical Communication in Distributed Industrial Systems  

Microsoft Academic Search

Low level industrial systems use simple data representation which reflects flat input and output structure of control industrial\\u000a system. This structure is directly mapped to the flat memory allocation. The structural data organization is used in upper\\u000a layers of industrial computer system. This article contains compare analysis of tag and object oriented data model used for\\u000a vertical communication in distributed

Rafa? Cupek; Marcin Fojcik; Olav Sande

428

A silicon early visual system as a model animal Tobi Delbruck *, Shih-Chii Liu  

E-print Network

A silicon early visual system as a model animal Tobi Delbruck *, Shih-Chii Liu Institute basic knowledge of brain function into practical electronic models are rare. Here we present a user-friendly silicon model of the early visual system that contributes to animal welfare. The silicon chip emulates

Delbruck, Tobi

429

Human-induced changes in animal populations and distributions, and the subsequent effects on fluvial systems  

Microsoft Academic Search

Humans have profoundly altered hydrological pathways and fluvial systems through their near-extirpation of native populations of animal species that strongly influenced hydrology and removal of surface sediment, and through the introduction of now-feral populations of animals that bring to bear a suite of different geomorphic effects on the fluvial system. In the category of effects of extirpation, examples are offered

David R. Butler

2006-01-01

430

Communication systems for the nonvocal based on frequent phoneme sequences.  

PubMed

A new type of nonvocal communication system has been developed for people unable to produce speech because of neuromotor impairment. It is designed to be as flexible as the alphabet, while requiring significantly fewer acts of selection on the part of the user. The items in this type of system are phoneme sequences which have a high frequency of occurrence in the phoneme sequences included, the fewer the selection gestures required. A system of this type--Par le si la b-- is available for French, and one for English--SPEEC (Sequences of Phonemes for Efficient English Communication)--is being field-tested. Both systems are implemented in lapboard form and on encoded eye-gaze selection (Etran) charts (Eichler, 1975) and are potentially compatible with a variety of electronic communication devices. To the nonvocal individual with good comprehension and the ability to begin learning regular sound-letter correspondences, this approach offers an unrestricted and potentially more rapid communication mode that may allow greater opportunity to develop and exercise language than is currently afforded by the alphabet or by preselected-vocabulary systems. PMID:6457934

Goodenough-Trepagnier, C; Prather, P

1981-09-01

431

The Globalstar mobile satellite system for worldwide personal communications  

NASA Astrophysics Data System (ADS)

Loral Aerospace Corporation along with Qualcomm Inc. have developed a satellite system which offers global mobile voice and data services to and from handheld and mobile user terminals with omni-directional antennas. By combining the use of low-earth orbit (LEO) satellites with existing terrestrial communications systems and innovative, highly efficient spread spectrum techniques, the Globalstar system provides users with low-cost, reliable communications throughout the world. The Globalstar space segment consists of a constellation of 48 LEO satellites in circular orbits with 750 NM (1389 km) altitude. Each satellite communicates with the mobile users via the satellite-user links and with gateway stations. The gateway stations handle the interface between the Globalstar network and the OSTN/PLMN systems. Globalstar transceivers are similar to currently proposed digital cellular telephones in size and have a serial number that will allow the end user to make and receive calls from or to that device anywhere in the world. The Globalstar system is designed to operate as a complement to existing local, long-distance, public, private and specialized telecommunications networks. Service is primarily designed to serve the rural and thin route communications needs of consumers, government users, and private networks.

Wiedeman, Robert A.; Viterbi, Andrew J.

432

A Low Earth Orbit satellite marine communication system demonstration  

NASA Technical Reports Server (NTRS)

An application of Low Earth Orbit (LEO) satellite communications technology was investigated during a joint Canadian/American scientific expedition to the north pole in the summer of 1994. The Canadian ice breaker involved, was equipped with a store-and-forward LEO satellite terminal which was linked to a ground station in St. John's, Newfoundland, via the near-polar-orbiting satellite, HealthSat-l. The objective was to evaluate the performance of such a system while providing an alternate means of communications in the far north. The system performed well, given its inherent limitations. All 151 attempts to send data files to the ship were successful. Only two (2) of the 35 attempts to send files from the ship were unsuccessful. The files ranged in size from 0.1 to 60 Kbytes. In the high arctic, above 80 deg north, this system often provided the only practical means of data communications. This experiment demonstrated the potential of such a system for not-real-time communications with remote and/or mobile stations, and highlighted the many issues involved. This paper describes the project objectives, system configuration and experimental procedure used, related technical issues, trial results, future work, and conclusions.

Elms, T. Keith; Butt, Kenneth A.; Asmus, Ken W.

1995-01-01

433

Communications of the Association for Information Systems  

E-print Network

Report: Open Access Publishing to Nurture the Sprouts of Knowledge and the Future of Information Systems to Nurture the Sprouts of Knowledge and the Future of Information Systems Research Michel Avital, Bo with a working prototype of an Open Access disciplinary repository entitled Sprouts (http://sprouts

Crowston, Kevin

434

Advance Computer Communication Systems in Hybrid Vehicles  

Microsoft Academic Search

This paper presents an overview of advance signal processors and computer systems in present day hybrid vehicles. The increase in processing speeds of the present day digital signal processors has helped in development of hybrid cars at commercial level. Hybrid vehicles make use of computer control systems that are extremely complicated. The recent advances in processing speed and power, the

P. V. Suryavanshi; V. K. Sharma; R. Sharma

2006-01-01

435

Communication Systems for Building Automation and Control  

Microsoft Academic Search

Building automation systems (BAS) provide automatic control of the conditions of indoor environments. The historical root and still core domain of BAS is the automation of heating, ventilation and air-conditioning systems in large functional buildings. Their primary goal is to realize significant savings in energy and reduce cost. Yet the reach of BAS has extended to include information from all

WOLFGANG KASTNER; GEORG NEUGSCHWANDTNER; STEFAN SOUCEK; H. MICHAEL NEWMAN

2005-01-01

436

Animal health in organic livestock production systems: a review  

Microsoft Academic Search

Organic livestock production is a means of food production with a large number of rules directed towards a high status of animal welfare, care for the environment, restricted use of medical drugs and the production of a healthy product without residues (pesticides or medical drugs). The intentions of organic livestock production have been formulated by the International Federation of Organic

A. Kijlstra; I. A. J. M. Eijck

2006-01-01

437

Integrated communication and control systems. I - Analysis  

NASA Technical Reports Server (NTRS)

The paper presents the results of an ICCS analysis focusing on discrete-time control systems subject to time-varying delays. The present analytical technique is applicable to integrated dynamic systems such as those encountered in advanced aircraft, spacecraft, and the real-time control of robots and machine tools via a high-speed network within an autonomous manufacturing environment. The significance of data latency and missynchronization between individual system components in ICCS networks is discussed in view of the time-varying delays.

Halevi, Yoram; Ray, Asok

1988-01-01

438

Program Support Communications Network (PSCN) facsimile system directory  

NASA Technical Reports Server (NTRS)

This directory provides a system description, a station listing, and operating procedures for the Program Support Communications Network (PSCN) NASA Facsimile System. The NASA Facsimile System is a convenient and efficient means of spanning the distance, time, and cost of transmitting documents from one person to another. In the spectrum of communication techniques, facsimile bridges the gap between mail and data transmission. Facsimile can transmit in a matter of minutes or seconds what would take a day or more by mail delivery. The NASA Facsimile System is composed of several makes and models of facsimile machines. The system also supports the 3M FaxXchange network controllers located at Marshall Space Flight Center (MSFC).

1992-01-01

439

NPOESS McMurdo Multimission Communications System  

Microsoft Academic Search

The National Oceanic & Atmospheric Administration (NOAA), Dept. of Defense (DoD), and National Aeronautics & Space Administration (NASA) are jointly acquiring the next-generation weather\\/environmental satellite system - the National Polar-orbiting Operational Environmental Satellite System (NPOESS). NPOESS replaces the current NOAA Polar-orbiting Operational Environmental Satellites (POES) and DoD Defense Meteorological Satellite Program (DMSP). NPOESS sensors will collect meteorological, oceanographic, climatological and

J. Paciaroni; C. Higgins; M. L. Jamilkowski

2010-01-01

440

Department of Communication Systems Lund Institute of Technology  

E-print Network

Department of Communication Systems Lund Institute of Technology Quality Improvement in Software approaches that are believed to improve the quality of the plat- form are presented. In order to study. The results from this thesis provide support for quality improvements in software platform development

441

The Business Communication Course and the Moodle Framework System  

ERIC Educational Resources Information Center

In this article I will argue that the use of learning content management systems is also justified in full-time education, especially in business education and communication studies. Nowadays not only multinational companies, but domestic medium enterprises also manage the training of new employees and existing staff with LCMSs. Companies in…

Krisko, Edina

2011-01-01

442

Communication Systems Simulator with Error Correcting Codes Using MATLAB  

ERIC Educational Resources Information Center

In this work, the characteristics of a simulator for channel coding techniques used in communication systems, are described. This software has been designed for engineering students in order to facilitate the understanding of how the error correcting codes work. To help students understand easily the concepts related to these kinds of codes, a…

Gomez, C.; Gonzalez, J. E.; Pardo, J. M.

2003-01-01

443

Range predictions for a CO(2) laser communication system.  

PubMed

Calculations are presented to permit range predictions of a CO(2) laser communication system when attenuation statistics are available. Both TV and digital transmission are considered. In the former case, an AM-FM modulation scheme is used. Direct demodulation is assumed. Examples are given in the use of the results to obtain range probabilities based on reported propagation statistics. PMID:20333019

Waksberg, A

1981-08-01

444

Volterra Series Based Signal Processing on Integrated Communication Systems  

E-print Network

of the circuit does not depend upon its previous history. In power series, all the coefficients a1, a2Volterra Series Based Signal Processing on Integrated Communication Systems Chunchen Liu1-modulation distortions and harmonic distortions in high frequency signal processing environments based on Volterra series

Fan, Jeffrey

445

Exploring capacity limits of fibre-optic communication systems  

Microsoft Academic Search

Summary form only given. The problem of evaluating the maximum rate of transmission of information, or capacity, of fibre-optic communication systems is discussed. We will describe a procedure we developed to derive a lower bound capacity of the dasiafibre channelpsila. Spectral efficiency of ~5 bits\\/s\\/Hz over 2000 km in one polarization will be shown to be theoretically achievable.

R.-J. Essiambre

2008-01-01

446

Evolving Large Scale UAV Communication System Adrian Agogino  

E-print Network

Evolving Large Scale UAV Communication System Adrian Agogino UCSC at NASA Ames Mail Stop 269 Corvallis, OR 97331 Kagan.Tumer@ oregonstate.edu ABSTRACT Unmanned Aerial Vehicles (UAVs) have traditionally powered unmanned aerial vehicles (UAVs) to fly long term missions at high altitudes. This will revo

Tumer, Kagan

447

46 CFR 169.713 - Engineroom communication system.  

Code of Federal Regulations, 2010 CFR

An efficient communication system must be provided between the principal steering station and the engineroom on vessels which are not equipped with pilothouse controls if, in the opinion of the Officer in Charge, Marine Inspection, this is necessary for proper operation of the...

2010-10-01

448

Microprocessor-Controlled Communications in an Advanced Instrument Landing System  

Microsoft Academic Search

The application of 4-bit microprocessors to the communication of the control and status signals found in an advanced aircraft instrument landing system is presented. The advantages as well as some of the peculiarities of such an approach are described. Among the benefits, one must include the possibility of a very convenient and understandable human interface.

S. E. Belter; C. R. Williams; S. C. Bass

1976-01-01

449

Performance of dimming control scheme in visible light communication system.  

PubMed

We investigate the performance of visible light communication (VLC) system with a pulse width modulation (PWM) dimming control scheme. Under this scheme, the communication quality in terms of number of transmitted bits and bit error rate (BER) of less than 10(-3) should be guaranteed. However, for on-off-keying (OOK) signal, the required data rate becomes 10 times as high as the original data rate when the duty cycle of dimming control signal is 0.1. To make the dimming control scheme easy to be implemented in VLC system, we propose the variable M-QAM OFDM VLC system, where M is adjusted according to the brightness of LED light in terms of duty cycle. The results show that with different duty cycles the required data rates are not higher than the original value and less LED lamp power is required to guarantee the communication quality, which makes the dimming control system that satisfies both communication and illumination requirements easy to be implemented and power-saving. PMID:23038525

Wang, Zixiong; Zhong, Wen-De; Yu, Changyuan; Chen, Jian; Francois, Chin Po Shin; Chen, Wei

2012-08-13

450

Training Paraprofessionals to Implement the Picture Exchange Communication System (PECS)  

ERIC Educational Resources Information Center

Based on Skinner's "Verbal Behavior" (1957), the picture exchange communication system (PECS) was designed to teach children with autism functional verbal behavior. Much research has demonstrated the effectiveness and efficiency of PECS in building verbal behavior. However, because PECS training is typically presented in a group format and later…

Sloman, Glenn Matthew

2010-01-01

451

Role of Communication Networks in Behavioral Systems Analysis  

ERIC Educational Resources Information Center

This article provides an overview of communication networks and the role of verbal behavior in behavioral systems analysis. Our discussion highlights styles of leadership in the design and implementation of effective organizational contingencies that affect ways by which coordinated work practices are managed. We draw upon literature pertaining to…

Houmanfar, Ramona; Rodrigues, Nischal Joseph; Smith, Gregory S.

2009-01-01

452

Relative Clause Sentence Production Using Augmentative and Alternative Communicative Systems.  

ERIC Educational Resources Information Center

Investigated adult English speakers' production of subject and object relative clause sentences using a picture/symbol-based augmentative and alternative communication (ACC) system with speech output. Most participants avoided the potential ambiguity that resulted from the absence of grammatical markers. Results indicate the combined effects of…

Sutton, Ann; Gallagher, Tanya; Morford, Jill; Shahnaz, Navid

2000-01-01

453

Near Field Communication and Bluetooth Bridge System for Mobile Commerce  

Microsoft Academic Search

This paper presents an innovation of a Near Field Communication (NFC) and Bluetooth bridge system for connecting Bluetooth enabled mobile devices to NFC enabled consumer services. Nowadays, there is an abundance of mobile phones and PDAs with Bluetooth capability in the consumer market but there are fewer devices with NFC capability. In order for NFC enabled consumer services and payment

C. Y. Leong; K. C. Ong; K. K. Tan; O. P. Gan

2006-01-01

454

COMMUNICATION A Facile Reporter System for the Experimental  

E-print Network

COMMUNICATION A Facile Reporter System for the Experimental Identification of Twin from other Gram-positive and Gram-negative bacteria resulted in efficient Tat-dependent export) pathway is a general protein export pathway found in the cyto- plasmic membranes of most bacteria

Palmer, Tracy

455

Prediction of the effects of rain on satellite communication systems  

Microsoft Academic Search

The major propagation effects for satellite communication systems operating above 4 GHz are caused by rain. With the possible exceptions of depolarization and multiple scattering at frequencies above 20 GHz, these effects may be calculated if the distribution of rain intensity is known in both time and space. The major effects-attenuation and interference-require information about path and volume averaged rain

R. K. Crane

1977-01-01

456

The Role of the Limbic System in Human Communication.  

ERIC Educational Resources Information Center

Linguistics has chosen as its niche the language component of human communication and, naturally enough, the neurolinguist has concentrated on lateralized language systems of the cerebral hemispheres. However, decoding a speaker's total message requires attention to gestures, facial expressions, and prosodic features, as well as other somatic and…

Lamendella, John T.

457

TD-LTE maritime trunking communication system based on TVWS  

NASA Astrophysics Data System (ADS)

This paper collects the measurement results of 470 MHZ-960MHZ spectrum in the coastal areas, and analyzes the characteristics of TV broadcast spectrum occupancy in the measurement region. Moreover, this article proposes construct the TD-LTE maritime trunking communication system using geolocation database, television database (TVDB) and cognitive radio (CR) technology.

Ren, Chunxiang; Chen, Xing; Li, Wanchao; Chen, Baodan

2014-10-01

458

Dedicated short range communications (DSRC) for intelligent transport system  

Microsoft Academic Search

In an effort to develop a complete DSRC system for ITS application, the authors have studied a lot of experimental facts which they are exploiting for the design. The wireless technology has been chosen properly which is capable of tackling the severe interferences present in the open road. For road to car communication, a combined digital technology like spread spectrum

Rabindranath Bera; Jitendranath Bera; Sanjib Sil; Sudip Dogra; Nirmalendu Bikas Sinha; D. Mondal

2006-01-01

459

Understanding and Influencing the Informal Communication System in the University  

ERIC Educational Resources Information Center

The university grapevine is described as an informal communication system developed out of basic human needs of belonging, influencing, and being accepted by a group. This article discusses when and why it becomes most active in the institution, and how it can be controlled. (LBH)

Mandel, Jerry E.; Hellweg, Susan A.

1977-01-01

460

Scattering Analysis for the Modeling of THz Communication Systems  

Microsoft Academic Search

Modeling propagation channels for future pico-cellular indoor THz communication systems requires the knowledge of the reflective properties of building materials. The reflectivity of smooth, optically thick materials can be modeled with Fresnel equations. In case of materials with a rough surface, diffuse scattering reduces the power reflected in the specular direction. Kirchhoff scattering theory can be employed to derive modified

Radoslaw Piesiewicz; Christian Jansen; Daniel Mittleman; Thomas Kleine-Ostmann; Martin Koch; Thomas Kurner

2007-01-01

461

Sensor and transmitter system for communication in pipelines  

DOEpatents

A system for sensing and communicating in a pipeline that contains a fluid. An acoustic signal containing information about a property of the fluid is produced in the pipeline. The signal is transmitted through the pipeline. The signal is received with the information and used by a control.

Cooper, John F.; Burnham, Alan K.

2013-01-29

462

Communication systems for grid integration of renewable energy resources  

Microsoft Academic Search

There is growing interest in renewable energy around the world. Since most renewable sources are intermittent in nature, it is a challenging task to integrate renewable energy resources into the power grid infrastructure. In this grid integration, communication systems are crucial technologies, which enable the accommodation of distributed renewable energy generation and play an extremely important role in monitoring, operating,

F. Richard Yu; Peng Zhang; Weidong Xiao; Paul Choudhury

2011-01-01

463

Multimedia systems for telemedicine and their communications requirements  

Microsoft Academic Search

Telemedicine is much more than just teleconferencing. ISDN could be used in some low-end applications, but many telemedicine applications will require the higher bandwidth and guaranteed qualities of service supported by ATM. We discuss the design of multimedia systems for telemedicine. First, various applications of telemedicine are presented, and their multimedia and communications requirements are discussed. A telemedicine prototype is

Yongmin Kim

1996-01-01

464

Direct cell-cell amplification and communication in immune system  

E-print Network

Direct cell-cell amplification and communication in immune system Direct cell-cell interactions cells of cell-cell recognition, as well as to a limited amount of activation stimul process has been that cytoskeleton plays a crucial role in signal amplification and perpetuation within a cell. Furthermore, contact

Shyamasundar, R.K.

465

Communications Pt-Ag Catalyst System for Hydroarylations with  

E-print Network

Communications Pt-Ag Catalyst System for Hydroarylations with Unactivated Arenes and Olefins Dmitry Summary: A series of Pt complexes activated by Ag(I) salts have been shown to catalyze Markovnikov hy of approximately 2 atm pressure of the olefin and 90 °C.4a Although Pt complexes have found widespread utility

Bell, Alexis T.

466

The Influence of Computer-Mediated Communication Systems on Community  

ERIC Educational Resources Information Center

As higher education institutions enter the intense competition of the rapidly growing global marketplace of online education, the leaders within these institutions are challenged to identify factors critical for developing and for maintaining effective online courses. Computer-mediated communication (CMC) systems are considered critical to…

Rockinson-Szapkiw, Amanda J.

2012-01-01

467

Designing MIMO communication systems: constellation choice and linear transceiver design  

Microsoft Academic Search

This papers considers the design of a mutiple-input multiple-output (MIMO) communication system with channel knowledge at the transmitter and receiver. The design methods available in the literature have addressed the following two aspects of the problem: a) choice of the symbol constellations for a given transmission scheme or b) choice of the optimal (linear) precoder and equalizer for a given

Daniel Perez Palomar; Sergio Barbarossa

2005-01-01

468

PREPARATION OF A VIRTUAL TOOLKIT FOR COMMUNICATION SYSTEMS  

Microsoft Academic Search

Communication Systems is offered at senior level as a three-credit, one semester course at Dordt College. Due to the number of topics covered, it turns out to be a very compact course with little time for experimentation. However, the course content is rich with processes that are best described by block diagrams which should come alive as students implement these

Murat Tanyel; Kathrine Nguru

2002-01-01

469

Group communication in the Amoeba distributed operating system  

Microsoft Academic Search

Primitives for broadcast communication that have been integrated with the Amoeba distributed operating system are introduced. The semantics of the broadcast primitives are simple and easy to understand, but are still powerful. The proposed primitives, for example, guarantee global ordering of broadcast messages. The proposed primitives are also efficient: a reliable broadcast can be done in just slightly more than

M. Frans Kaashoek; Andrew S. Tanenbaum

1991-01-01

470

Animated pedagogical agents: How the presence and nonverbal communication of a virtual instructor affect perceptions and learning outcomes in a computer-based environment about basic physics concepts  

NASA Astrophysics Data System (ADS)

One important but under-researched area of instructional technology concerns the effects of animated pedagogical agents (APAs), or lifelike characters designed to enhance learning in computer-based environments. This research sought to broaden what is currently known about APAs' instructional value by investigating the effects of agents' visual presence and nonverbal communication. A theoretical framework based on APA literature published in the past decade guided the design of the study. This framework sets forth that APAs impact learning through their presence and communication. The communication displayed by an APA involves two distinct kinds of nonverbal cues: cognitive (hand and arm gestures) and affective (facial expressions). It was predicted that the presence of an agent would enhance learning and that nonverbal communication would amplify these effects. The research utilized a between-subjects experimental design. Participants were randomly assigned to treatment conditions in a controlled lab setting, and group means were compared with a MANCOVA. Participants received (1) a non-animated agent, (2) an agent with hand and arm gestures, (3) an agent with facial expressions, or (4) a fully animated agent. The agent appeared in a virtual learning environment focused on Kepler's laws of planetary motion. A control group did not receive the visual presence of an agent. Two effects were studied: participants' perceptions and their learning outcomes. Perceptions were measured with an attitudinal survey with five subscales. Learning outcomes were measured with an open-ended recall test, a multiple choice comprehension test, and an open-ended transfer test. Learners presented with an agent with affective nonverbal communication comprehended less than learners exposed to a non-animated agent. No significant differences were observed when a group exposed to a fully animated agent was compared to a group with a non-animated agent. Adding both nonverbal communication channels mitigated the disadvantages of adding just one kind of nonverbal cue. No statistically significant differences were observed on measures of recall or transfer, or on the attitudinal survey. The research supports the notion that invoking a human-like presence in a virtual learning environment prompts strong expectations about the character's realism. When these expectations are not met, learning is hindered.

Frechette, M. Casey

471

S-band antenna phased array communications system  

NASA Technical Reports Server (NTRS)

The development of an S-band antenna phased array for spacecraft to spacecraft communication is discussed. The system requirements, antenna array subsystem design, and hardware implementation are examined. It is stated that the phased array approach offers the greatest simplicity and lowest cost. The objectives of the development contract are defined as: (1) design of a medium gain active phased array S-band communications antenna, (2) development and test of a model of a seven element planar array of radiating elements mounted in the appropriate cavity matrix, and (3) development and test of a breadboard transmit/receive microelectronics module.

Delzer, D. R.; Chapman, J. E.; Griffin, R. A.

1975-01-01

472

Internet-Based System for Voice Communication With the ISS  

NASA Technical Reports Server (NTRS)

The Internet Voice Distribution System (IVoDS) is a voice-communication system that comprises mainly computer hardware and software. The IVoDS was developed to supplement and eventually replace the Enhanced Voice Distribution System (EVoDS), which, heretofore, has constituted the terrestrial subsystem of a system for voice communications among crewmembers of the International Space Station (ISS), workers at the Payloads Operations Center at Marshall Space Flight Center, principal investigators at diverse locations who are responsible for specific payloads, and others. The IVoDS utilizes a communication infrastructure of NASA and NASArelated intranets in addition to, as its name suggests, the Internet. Whereas the EVoDS utilizes traditional circuitswitched telephony, the IVoDS is a packet-data system that utilizes a voice over Internet protocol (VOIP). Relative to the EVoDS, the IVoDS offers advantages of greater flexibility and lower cost for expansion and reconfiguration. The IVoDS is an extended version of a commercial Internet-based voice conferencing system that enables each user to participate in only one conference at a time. In the IVoDS, a user can receive audio from as many as eight conferences simultaneously while sending audio to one of them. The IVoDS also incorporates administrative controls, beyond those of the commercial system, that provide greater security and control of the capabilities and authorizations for talking and listening afforded to each user.

Chamberlain, James; Myers, Gerry; Clem, David; Speir, Terri

2005-01-01

473

Corona Considerations in Submarine Cable Communications Systems  

Microsoft Academic Search

Underwater repeatered telephone cable systems are series powered by high-voltage dc. Each repeater and equalizer contains a power separation filter (PSF) for extracting the dc current from the center conductor of the coaxial cable while allowing signal transmission. Corona discharges occurring across the high-voltage components are coupled through reactive components to the repeater's terminals. Each of the experimentally observed pulse

Earnest Franke

1974-01-01

474

Cryptanalysis of a chaotic secure communication system  

NASA Astrophysics Data System (ADS)

Recently a chaotic encryption system has been proposed by P. Garc?´a et al. It represents an improvement over an algorithm previously presented by some of the same authors. In this Letter, several weaknesses of the new cryptosystem are pointed out and four successful cryptanalytic attacks are described.

Alvarez, G.; Montoya, F.; Romera, M.; Pastor, G.

2003-01-01

475

Power Control Algorithms for Satellite Communication Systems  

Microsoft Academic Search

Three different ground terminal transmit power control concepts for a Satcom system are examined. The effectiveness of constant satellite power (CSP) sharing among the carriers and adaptive satellite power (ASP) sharing is compared with constant ground terminal transmit power (CTP). It is shown that ASP offers substantial advantages over CSP in combating environmental degradations and that both can increase link

A. Ince; D. Brown; J. Midgley

1976-01-01

476

EVALUATION FOR DARPA COMMUNICATOR SPOKEN DIALOGUE SYSTEMS  

Microsoft Academic Search

The overall objective of the DARPA COMMUNICATORproject is to support rapid, cost-effective development of multi-modal speech- enabled dialogue systems with advanced conversational capabilities, such as plan optimization, explanation and nego tiation. In order to make this a reality, we need to find methods for evaluating the contribution of various techniques to the users' willingne ss and ability to use the

Marilyn Walker; Lynette Hirschman; John Aberdeen

2000-01-01

477

Efficient resource allocation scheme for visible-light communication system  

NASA Astrophysics Data System (ADS)

A visible-light communication utilizing LED has many advantagies such as visibility of information, high SNR (Signal to Noise Ratio), low installation cost, usage of existing illuminators, and high security. Furthermore, exponentially increasing needs and quality of LED have helped the development of visible-light communication. The visibility is the most attractive property in visible-light communication system, but it is difficult to ensure visibility and transmission efficiency simultaneously during initial access because of the small amount of initial access process signals. In this paper, we propose an efficient resource allocation scheme at initial access for ensuring visibility with high resource utilization rate and low data transmission failure rate. The performance has been evaluated through the numerical analysis and simulation results.

Kim, Woo-Chan; Bae, Chi-Sung; Cho, Dong-Ho; Shin, Hong-Seok; Jung, D. K.; Oh, Y. J.

2009-01-01

478

Advanced Communications Technology Satellite (ACTS): Four-Year System Performance  

NASA Technical Reports Server (NTRS)

The Advanced Communications Technology Satellite (ACTS) was conceived at the National Aeronautics and Space Administration (NASA) in the late 1970's as a follow-on program to ATS and CTS to continue NASA's long history of satellite communications projects. The ACTS project set the stage for the C-band satellites that started the industry, and later the ACTS project established the use of Ku-band for video distribution and direct-to-home broadcasting. ACTS, launched in September 1993 from the space shuttle, created a revolution in satellite system architecture by using digital communications techniques employing key technologies such as a fast hopping multibeam antenna, an on-board baseband processor, a wide-band microwave switch matrix, adaptive rain fade compensation, and the use of 900 MHz transponders operating at Ka-band frequencies. This paper describes the lessons learned in each of the key ACTS technology areas, as well as in the propagation investigations.

Acosta, Roberto J.; Bauer, Robert; Krawczyk, Richard J.; Reinhart, Richard C.; Zernic, Michael J.; Gargione, Frank

1999-01-01

479

Shuttle/payload communications and data systems interface analysis  

NASA Technical Reports Server (NTRS)

The payload/orbiter functional command signal flow and telemetry signal flow are discussed. Functional descriptions of the various orbiter communication/avionic equipment involved in processing a command to a payload either from the ground through the orbiter by the payload specialist on the orbiter are included. Functional descriptions of the various orbiter communication/avionic equipment involved in processing telemetry data by the orbiter and transmitting the processed data to the ground are presented. The results of the attached payload/orbiter single processing and data handling system evaluation are described. The causes of the majority of attached payload/orbiter interface problems are delineated. A refined set of required flux density values for a detached payload to communicate with the orbiter is presented.

Huth, G. K.

1980-01-01

480

A high resolution analog fiber optics data communications system  

Microsoft Academic Search

A high resolution fiber optics communications system (FOCS) for analog signals has been designed, built, and tested. The system consists of a small transmitter and receiver pair and an optical wave guide. A combination of voltage-to-frequency-to-voltage and pulse width modulation is used to reconstruct a plus or minus 10 volt analog output signal from an identical plus or minus 10

G. J. Grimes; D. R. Stevens

1976-01-01

481

Animal Ears  

NSDL National Science Digital Library

This activity (page 2 of the PDF) is a full inquiry investigation into animal behavior and communication. Groups of learners will fashion a headband with fake ears, similar in shape to those of the animal they are going to observe. Then, they record observations of the animal’s reactions when a learner, wearing the ears in different positions, brings it a snack. Learners develop categories of behavior to organize and evaluate the results. Safety Note: an adult handler must be present if working with a horse or even a large dog. Relates to linked video, DragonflyTV: Horse Ears.

Twin Cities Public Television, Inc.

2006-01-01

482

Rodent Scope: A User-Configurable Digital Wireless Telemetry System for Freely Behaving Animals  

PubMed Central

This paper describes the design and implementation of a wireless neural telemetry system that enables new experimental paradigms, such as neural recordings during rodent navigation in large outdoor environments. RoSco, short for Rodent Scope, is a small lightweight user-configurable module suitable for digital wireless recording from freely behaving small animals. Due to the digital transmission technology, RoSco has advantages over most other wireless modules of noise immunity and online user-configurable settings. RoSco digitally transmits entire neural waveforms for 14 of 16 channels at 20 kHz with 8-bit encoding which are streamed to the PC as standard USB audio packets. Up to 31 RoSco wireless modules can coexist in the same environment on non-overlapping independent channels. The design has spatial diversity reception via two antennas, which makes wireless communication resilient to fading and obstacles. In comparison with most existing wireless systems, this system has online user-selectable independent gain control of each channel in 8 factors from 500 to 32,000 times, two selectable ground references from a subset of channels, selectable channel grounding to disable noisy electrodes, and selectable bandwidth suitable for action potentials (300 Hz–3 kHz) and low frequency field potentials (4 Hz–3 kHz). Indoor and outdoor recordings taken from freely behaving rodents are shown to be comparable to a commercial wired system in sorting for neural populations. The module has low input referred noise, battery life of 1.5 hours and transmission losses of 0.1% up to a range of 10 m. PMID:24587144

Ball, David; Kliese, Russell; Windels, Francois; Nolan, Christopher; Stratton, Peter; Sah, Pankaj; Wiles, Janet

2014-01-01

483

The Iridium (tm) system: Personal communications anytime, anyplace  

NASA Technical Reports Server (NTRS)

The Iridium system is designed to provide handheld personal communications between diverse locations around the world at any time and without prior knowledge of the location of the personal units. This paper provides an overview of the system, the services it provides, its operation, and an overview of the commercial practices and relatively high volume satellite production techniques which will make the system cost effective. A constellation of 66 satellites will provide an orbiting, spherical-shell, infrastructure for this global calling capability. The satellites act as tall cellular towers and allow convenient operation for portable handheld telephones. The system will provide a full range of services including voice, paging, data, geolocation, and fax capabilities. Motorola is a world leader in the production of high volume, high quality, reliable telecommunications hardware. One of Iridium's goals is to apply these production techniques to high reliability space hardware. Concurrent engineering, high performance work teams, advanced manufacturing technologies, and improved assembly and test methods are some of the techniques that will keep the Iridium system cost effective. Mobile, global, flexible personal communications are coming that will allow anyone to call or receive a call from/to anyplace at anytime. The Iridium system will provide communications where none exist today. This connectivity will allow increased information transfer, open new markets for various business endeavors, and in general increase productivity and development.

Hatlelid, John E.; Casey, Larry

1993-01-01

484

Security analysis of communication system based on the synchronization of different order chaotic systems  

E-print Network

This work analyzes the security weakness of a recently proposed communication method based on chaotic modulation and masking using synchronization of two chaotic systems with different orders. It is shown that its application to secure communication is unsafe, because it can be broken in two different ways, by high-pass filtering and by reduced order system synchronization, without knowing neither the system parameter values nor the system key.

G. Alvarez; L. Hernandez; J. Munoz; F. Montoya; Shujun Li

2005-06-27

485

MOAB: a spatially explicit, individual-based expert system for creating animal foraging models  

USGS Publications Warehouse

We describe the development, structure, and corroboration process of a simulation model of animal behavior (MOAB). MOAB can create spatially explicit, individual-based animal foraging models. Users can create or replicate heterogeneous landscape patterns, and place resources and individual animals of a goven species on that landscape to simultaneously simulate the foraging behavior of multiple species. The heuristic rules for animal behavior are maintained in a user-modifiable expert system. MOAB can be used to explore hypotheses concerning the influence of landscape patttern on animal movement and foraging behavior. A red fox (Vulpes vulpes L.) foraging and nest predation model was created to test MOAB's capabilities. Foxes were simulated for 30-day periods using both expert system and random movement rules. Home range size, territory formation and other available simulation studies. A striped skunk (Mephitis mephitis L.) model also was developed. The expert system model proved superior to stochastic in respect to territory formation, general movement patterns and home range size.

Carter, J.; Finn, J.T.

1999-01-01

486

The 30/20 GHz communications system functional requirements  

NASA Technical Reports Server (NTRS)

The characteristics of 30/20 GHz usage in satellite systems to be used in support of projected communication requirements of the 1990's are defined. A requirements analysis which develops projected market demand for satellite services by general and specialized carriers and an analysis of the impact of propagation and system constraints on 30/20 GHz operation are included. A set of technical performance characteristics for the 30/20 GHz systems which can serve the resulting market demand and the experimental program necessary to verify technical and operational aspects of the proposed systems is also discussed.

Siperko, C. M.; Frankfort, M.; Markham, R.; Wall, M.

1981-01-01

487

Control of communicable diseases; restrictions on African rodents, prairie dogs, and certain other animals. Interim final rule; opportunity for public comment.  

PubMed

The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) are issuing this interim final rule to amend their regulations to establish new restrictions and modify existing restrictions on the import, capture, transport, sale, barter, exchange, distribution, and release of African rodents, prairie dogs, and certain other animals. We are taking this action to prevent the spread of monkeypox, a communicable disease, in the United States. PMID:14610759

2003-11-01

488

Radio frequency communication system utilizing radiating transmission lines  

DOEpatents

A radio communication system for use in tunnels, mines, buildings or other shielded locations in which a pair of radiating transmission lines (30), (31) extend through such location in spaced coextensive relation to each other. Each transmission line (30), (31) has at least one unidirectional amplifier (32), (33) interposed therein with the sense of the unidirectional amplifier (32) of one transmission line (30) being opposite to the sense of the unidirectional amplifier (33) of the other transmission line (31). Each of the amplifiers (32), (33) has a gain which is less than the coupling loss between the transmission lines (30), (31). Two or more mobile transceivers (35) in the location served by the system are coupled to the transmission lines (30), (31) by electromagnetic wave propagation in space in order to communicate directly with each other at a given radio frequency within the frequency range of the system.

Struven, Warren C. (San Carlos, CA)

1984-01-01

489

On modeling of integrated communication and control systems  

NASA Technical Reports Server (NTRS)

The mathematical modeling scheme proposed by Ray and Halevi (1988) for integrated communication and control systems is considered analytically, with an emphasis on the effect of introducing varying and distributed time delays to account for asynchronous time-division multiplexing in the communication part of the system. Ray and Halevi applied a state-transition concept to transform the original continuous-time model into a discrete-time model; the same approach was used by Kalman and Bertram (1959) to model various types of sampled data systems which are not subject to induced delays. The relationship between the two modeling schemes is explored, and it is shown that, although the Kalman-Bertram method has the advantage of a unified approach, it becomes inconvenient when varying delays appear in the control loop.

Liou, Luen-Woei; Ray, Asok

1990-01-01

490

Ammonia Emissions and Animal Agriculture Susan W. Gay, Extension Engineer, Biological Systems Engineering, Virginia Tech  

E-print Network

Ammonia Emissions and Animal Agriculture Susan W. Gay, Extension Engineer, Biological Systems the main air quality concern related to agricultural animal production. However, ammonia emissions from that cover ammonia emissions in the United States were adopted in 1997. These regulations will have a signifi

Liskiewicz, Maciej

491

Behavioral/Systems/Cognitive Humans Mimicking Animals: A Cortical Hierarchy for  

E-print Network

to represent auditory experience or "expertise" in general rather than showing exclusive sensitivity to humanBehavioral/Systems/Cognitive Humans Mimicking Animals: A Cortical Hierarchy for Human Vocal of complex human non-verbal vocalizations--human-mimicked versions of animal vocalizations--we found

492

Human-induced changes in animal populations and distributions, and the subsequent effects on fluvial systems  

E-print Network

of aquatic systems have altered animal populations and attendant zoogeomorphic processes. For example, dam for fish. Salmonid species, such as salmon and trout, directly Geomorphology 79 (2006) 448­459 www also profoundly alter native animal populations within and along riparian corridors, in turn affecting

493

LOTUS 1-2-3-BASED SYSTEM FOR RECORDING AND MAINTAINING BODY WEIGHT OF LABORATORY ANIMALS  

EPA Science Inventory

Body weight maintenance is required in a variety of behavioral and physiological studies. C-based animal weighing system is described which features automated data collection and allows for accurate control of body weight in test animals via manipulation of food intake. ajor syst...

494

Comparison of Communication Architectures for Spacecraft Modular Avionics Systems  

NASA Technical Reports Server (NTRS)

This document is a survey of publicly available information concerning serial communication architectures used, or proposed to be used, in aeronautic and aerospace applications. It focuses on serial communication architectures that are suitable for low-latency or real-time communication between physically distributed nodes in a system. Candidates for the study have either extensive deployment in the field, or appear to be viable for near-term deployment. Eleven different serial communication architectures are considered, and a brief description of each is given with the salient features summarized in a table in appendix A. This survey is a product of the Propulsion High Impact Avionics Technology (PHIAT) Project at NASA Marshall Space Flight Center (MSFC). PHIAT was originally funded under the Next Generation Launch Technology (NGLT) Program to develop avionics technologies for control of next generation reusable rocket engines. After the announcement of the Space Exploration Initiative, the scope of the project was expanded to include vehicle systems control for human and robotics missions. As such, a section is included presenting the rationale used for selection of a time-triggered architecture for implementation of the avionics demonstration hardware developed by the project team

Gwaltney, D. A.; Briscoe, J. M.

2006-01-01

495

Development of a SiPM-based PET imaging system for small animals  

NASA Astrophysics Data System (ADS)

Advances in small animal positron emission tomography (PET) imaging have been accelerated by many new technologies such as the successful incorporation of silicon photomultiplier (SiPM). In this paper, we have developed a compact, lightweight PET imaging system that is based on SiPM detectors for small animals imaging, which could be integrated into a multi-modality imaging system. This PET imaging system consists of a stationary detector gantry, a motor-controlled animal bed module, electronics modules, and power supply modules. The PET detector, which was designed as a multi-slice circular ring geometry of 27 discrete block detectors, is composed of a cerium doped lutetium-yttrium oxyorthosilicate (LYSO) scintillation crystal and SiPM arrays. The system has a 60 mm transaxial field of view (FOV) and a 26 mm axial FOV. Performance tests (e.g. spatial resolution, energy resolution, and sensitivity) and phantom and animal imaging studies were performed to evaluate the imaging performance of the PET imaging system. The performance tests and animal imaging results demonstrate the feasibility of an animal PET system based on SiPM detectors and indicate that SiPM detectors can be promising photodetectors in animal PET instrumentation development.

Lu, Yanye; Yang, Kun; Zhou, Kedi; Zhang, Qiushi; Pang, Bo; Ren, Qiushi

2014-04-01

496

26 CFR 49.4253-9 - Exemption for certain interior communication systems.  

Code of Federal Regulations, 2010 CFR

...which is not connected with a communications system. (c) Examples. The following are examples of interior communication systems: (1) Burglar, fire...one of the points, such as water level, water pressure,...

2010-04-01

497

IRECIN Nano-satellite communication system and ground segment  

NASA Astrophysics Data System (ADS)

On board resources necessary to perform the mission tasks are very limited in nano-satellites. This paper proposes a real-time multi-processing system for the communication system between ground segment and IRECIN nano-satellite. The first microprocessor is devoted to interface to the rice-transceiver subsystem decoding packet information and the second one is in charge to communicate with the other subsystems through I 2C bus. It uses UHF band and less than 1 W in RF. All electronic components are SMD technology in order to reduce weight and size. The realized electronic boards are completely developed, realized and tested at the Vitrociset S.P.A. under control of Research and Develop Group. This multi-processor system even allows managing the tasks of the microprocessor eventually damaged, the microprocessor still working takes the functionalities of the first one using simpler algorithms. This choice assures an increasing nano-satellite life time. Moreover, the depicted method allows to free the on-board main microprocessor from the control functions of the communication data, increasing its communication capabilities with the other subsystems. The proposed system is implemented on the IRECIN, a modular nano-satellite weighing less than 1.5 kg, constituted by 16 external sides with surface-mounted solar cells and three internal Al plates, kept together by four steel bars. Lithium-ion batteries are added for eclipse operations. Attitude is determined by two three-axis magnetometers and the solar panel data. Control is provided by an active magnetic control system. The spacecraft will be spin-stabilized with the spin-axis normal to the orbit.

Ferrante, M.; Povia, M.; Di Ciolo, L.; Ortenzi, A.; Petrozzi, M.

2005-01-01

498

Design and Implementation of Communication System among Heterogeneous Multi-Agent System  

Microsoft Academic Search

Unfortunately heterogeneous multi-agent systems use the different language to describe agents and services provided by agents. For example, there are Java agent development framework (JADE) and component-based autonomic layered middleware (CALM). The JADE uses agent communication language (ACL) and semantic language (SL) proposed by FIPA (Foundation for Intelligent Physical Agents). The ACL is a language to communicate between agents. And

Yoe-Jin Yoon; Kee-Hyun Choi; Dong-Ryeol Shin

2008-01-01

499

Ionospheric effects on C3I satellite communications systems in Greenland  

NASA Astrophysics Data System (ADS)

The effects of polar ionospheric scintillation fading on U.S. military satellite communications systems in Greenland are reviewed. The operational type of satellite communications testing, conducted for the past 10 years to evaluate the feasibility of replacing the traditional HF radio links with satellite communications links is described. Some future plans for the operational use of satellite communications in Greenland are identified.

Johnson, A.; Taagholt, J.

1985-06-01

500

Successive AoA estimation: Revealing the second path for 60 GHz communication system  

Microsoft Academic Search

60 GHz communication system is a viable candidate to support very high data throughput for wireless communication. To compensate for high path loss at 60 GHz frequency, a large number of antenna elements are employed to form highly directional beams for communication range extension. However, communication paths are easily be blocked by human movement. Switching to the second best path

Y. Ming Tsang; Ada S. Y. Poon

2011-01-01