Sample records for negative sequence relay

  1. Spreading Sequence System for Full Connectivity Relay Network

    NASA Technical Reports Server (NTRS)

    Kwon, Hyuck M. (Inventor); Pham, Khanh D. (Inventor); Yang, Jie (Inventor)

    2018-01-01

    Fully connected uplink and downlink fully connected relay network systems using pseudo-noise spreading and despreading sequences subjected to maximizing the signal-to-interference-plus-noise ratio. The relay network systems comprise one or more transmitting units, relays, and receiving units connected via a communication network. The transmitting units, relays, and receiving units each may include a computer for performing the methods and steps described herein and transceivers for transmitting and/or receiving signals. The computer encodes and/or decodes communication signals via optimum adaptive PN sequences found by employing Cholesky decompositions and singular value decompositions (SVD). The PN sequences employ channel state information (CSI) to more effectively and more securely computing the optimal sequences.

  2. Relay Sequence Generation Software

    NASA Technical Reports Server (NTRS)

    Gladden, Roy E.; Khanampompan, Teerapat

    2009-01-01

    Due to thermal and electromagnetic interactivity between the UHF (ultrahigh frequency) radio onboard the Mars Reconnaissance Orbiter (MRO), which performs relay sessions with the Martian landers, and the remainder of the MRO payloads, it is required to integrate and de-conflict relay sessions with the MRO science plan. The MRO relay SASF/PTF (spacecraft activity sequence file/ payload target file) generation software facilitates this process by generating a PTF that is needed to integrate the periods of time during which MRO supports relay activities with the rest of the MRO science plans. The software also generates the needed command products that initiate the relay sessions, some features of which are provided by the lander team, some are managed by MRO internally, and some being derived.

  3. Secure relay selection based on learning with negative externality in wireless networks

    NASA Astrophysics Data System (ADS)

    Zhao, Caidan; Xiao, Liang; Kang, Shan; Chen, Guiquan; Li, Yunzhou; Huang, Lianfen

    2013-12-01

    In this paper, we formulate relay selection into a Chinese restaurant game. A secure relay selection strategy is proposed for a wireless network, where multiple source nodes send messages to their destination nodes via several relay nodes, which have different processing and transmission capabilities as well as security properties. The relay selection utilizes a learning-based algorithm for the source nodes to reach their best responses in the Chinese restaurant game. In particular, the relay selection takes into account the negative externality of relay sharing among the source nodes, which learn the capabilities and security properties of relay nodes according to the current signals and the signal history. Simulation results show that this strategy improves the user utility and the overall security performance in wireless networks. In addition, the relay strategy is robust against the signal errors and deviations of some user from the desired actions.

  4. The sequence relay selection strategy based on stochastic dynamic programming

    NASA Astrophysics Data System (ADS)

    Zhu, Rui; Chen, Xihao; Huang, Yangchao

    2017-07-01

    Relay-assisted (RA) network with relay node selection is a kind of effective method to improve the channel capacity and convergence performance. However, most of the existing researches about the relay selection did not consider the statically channel state information and the selection cost. This shortage limited the performance and application of RA network in practical scenarios. In order to overcome this drawback, a sequence relay selection strategy (SRSS) was proposed. And the performance upper bound of SRSS was also analyzed in this paper. Furthermore, in order to make SRSS more practical, a novel threshold determination algorithm based on the stochastic dynamic program (SDP) was given to work with SRSS. Numerical results are also presented to exhibit the performance of SRSS with SDP.

  5. Synaptic plasticity in a cerebellum-like structure depends on temporal order

    NASA Astrophysics Data System (ADS)

    Bell, Curtis C.; Han, Victor Z.; Sugawara, Yoshiko; Grant, Kirsty

    1997-05-01

    Cerebellum-like structures in fish appear to act as adaptive sensory processors, in which learned predictions about sensory input are generated and subtracted from actual sensory input, allowing unpredicted inputs to stand out1-3. Pairing sensory input with centrally originating predictive signals, such as corollary discharge signals linked to motor commands, results in neural responses to the predictive signals alone that are Negative images' of the previously paired sensory responses. Adding these 'negative images' to actual sensory inputs minimizes the neural response to predictable sensory features. At the cellular level, sensory input is relayed to the basal region of Purkinje-like cells, whereas predictive signals are relayed by parallel fibres to the apical dendrites of the same cells4. The generation of negative images could be explained by plasticity at parallel fibre synapses5-7. We show here that such plasticity exists in the electrosensory lobe of mormyrid electric fish and that it has the necessary properties for such a model: it is reversible, anti-hebbian (excitatory postsynaptic potentials (EPSPs) are depressed after pairing with a postsynaptic spike) and tightly dependent on the sequence of pre- and postsynaptic events, with depression occurring only if the postsynaptic spike follows EPSP onset within 60 ms.

  6. A New Method for Setting Calculation Sequence of Directional Relay Protection in Multi-Loop Networks

    NASA Astrophysics Data System (ADS)

    Haijun, Xiong; Qi, Zhang

    2016-08-01

    Workload of relay protection setting calculation in multi-loop networks may be reduced effectively by optimization setting calculation sequences. A new method of setting calculation sequences of directional distance relay protection in multi-loop networks based on minimum broken nodes cost vector (MBNCV) was proposed to solve the problem experienced in current methods. Existing methods based on minimum breakpoint set (MBPS) lead to more break edges when untying the loops in dependent relationships of relays leading to possibly more iterative calculation workloads in setting calculations. A model driven approach based on behavior trees (BT) was presented to improve adaptability of similar problems. After extending the BT model by adding real-time system characters, timed BT was derived and the dependency relationship in multi-loop networks was then modeled. The model was translated into communication sequence process (CSP) models and an optimization setting calculation sequence in multi-loop networks was finally calculated by tools. A 5-nodes multi-loop network was applied as an example to demonstrate effectiveness of the modeling and calculation method. Several examples were then calculated with results indicating the method effectively reduces the number of forced broken edges for protection setting calculation in multi-loop networks.

  7. Space processing applications rocket project SPAR 4, engineering report

    NASA Technical Reports Server (NTRS)

    Reeves, F. (Compiler)

    1980-01-01

    The materials processing experiments in space, conducted on the SPAR 4 Black Brant VC rocket, are described and discussed. The SPAR 4 payload configuration, the rocket performance, and the flight sequence are reported. The results, analyses, and anomalies of the four experiments are discussed. The experiments conducted were the uniform dispersions of crystallization processing, the contained polycrstalline solidification in low gravity, the containerless processing of ferromagnetic materials, and the containerless processing technology. The instrumentation operations, payload power relay anomaly, relay postflight operational test, and relay postflight shock test are reported.

  8. Outage probability of a relay strategy allowing intra-link errors utilizing Slepian-Wolf theorem

    NASA Astrophysics Data System (ADS)

    Cheng, Meng; Anwar, Khoirul; Matsumoto, Tad

    2013-12-01

    In conventional decode-and-forward (DF) one-way relay systems, a data block received at the relay node is discarded, if the information part is found to have errors after decoding. Such errors are referred to as intra-link errors in this article. However, in a setup where the relay forwards data blocks despite possible intra-link errors, the two data blocks, one from the source node and the other from the relay node, are highly correlated because they were transmitted from the same source. In this article, we focus on the outage probability analysis of such a relay transmission system, where source-destination and relay-destination links, Link 1 and Link 2, respectively, are assumed to suffer from the correlated fading variation due to block Rayleigh fading. The intra-link is assumed to be represented by a simple bit-flipping model, where some of the information bits recovered at the relay node are the flipped version of their corresponding original information bits at the source. The correlated bit streams are encoded separately by the source and relay nodes, and transmitted block-by-block to a common destination using different time slots, where the information sequence transmitted over Link 2 may be a noise-corrupted interleaved version of the original sequence. The joint decoding takes place at the destination by exploiting the correlation knowledge of the intra-link (source-relay link). It is shown that the outage probability of the proposed transmission technique can be expressed by a set of double integrals over the admissible rate range, given by the Slepian-Wolf theorem, with respect to the probability density function ( pdf) of the instantaneous signal-to-noise power ratios (SNR) of Link 1 and Link 2. It is found that, with the Slepian-Wolf relay technique, so far as the correlation ρ of the complex fading variation is | ρ|<1, the 2nd order diversity can be achieved only if the two bit streams are fully correlated. This indicates that the diversity order exhibited in the outage curve converges to 1 when the bit streams are not fully correlated. Moreover, the Slepian-Wolf outage probability is proved to be smaller than that of the 2nd order maximum ratio combining (MRC) diversity, if the average SNRs of the two independent links are the same. Exact as well as asymptotic expressions of the outage probability are theoretically derived in the article. In addition, the theoretical outage results are compared with the frame-error-rate (FER) curves, obtained by a series of simulations for the Slepian-Wolf relay system based on bit-interleaved coded modulation with iterative detection (BICM-ID). It is shown that the FER curves exhibit the same tendency as the theoretical results.

  9. Advanced Strategic and Tactical Relay Request Management for the Mars Relay Operations Service

    NASA Technical Reports Server (NTRS)

    Allard, Daniel A.; Wallick, Michael N.; Gladden, Roy E.; Wang, Paul; Hy, Franklin H.

    2013-01-01

    This software provides a new set of capabilities for the Mars Relay Operations Service (MaROS) in support of Strategic and Tactical relay, including a highly interactive relay request Web user interface, mission control over relay planning time periods, and mission management of allowed strategic vs. tactical request parameters. Together, these new capabilities expand the scope of the system to include all elements critical for Tactical relay operations. Planning of replay activities spans a time period that is split into two distinct phases. The first phase is called Strategic, which begins at the time that relay opportunities are identified, and concludes at the point that the orbiter generates the flight sequences for on board execution. Any relay request changes from this point on are called Tactical. Tactical requests, otherwise called Orbit - er Relay State Changes (ORSC), are highly restricted in terms of what types of changes can be made, and the types of parameters that can be changed may differ from one orbiter to the next. For example, one orbiter may be able to delay the start of a relay request, while another may not. The legacy approach to ORSC management involves exchanges of e-mail with "requests for change" and "acknowledgement of approval," with no other tracking of changes outside of e-mail folders. MaROS Phases 1 and 2 provided the infrastructure for strategic relay for all supported missions. This new version, 3.0, introduces several capabilities that fully expand the scope of the system to include tactical relay. One new feature allows orbiter users to manage and "lock" Planning Periods, which allows the orbiter team to formalize the changeover from Strategic to Tactical operations. Another major feature allows users to interactively submit tactical request changes via a Web user interface. A third new feature allows orbiter missions to specify allowed tactical updates, which are automatically incorporated into the tactical change process. This software update is significant in that it provides the only centralized service for tactical request management available for relay missions.

  10. Mars Reconnaissance Orbiter Navigation Strategy for Mars Science Laboratory Entry, Descent and Landing Telecommunication Relay Support

    NASA Technical Reports Server (NTRS)

    Williams, Jessica L.; Menon, Premkumar R.; Demcak, Stuart W.

    2012-01-01

    The Mars Reconnaissance Orbiter (MRO) is an orbiting asset that performs remote sensing observations in order to characterize the surface, subsurface and atmosphere of Mars. To support upcoming NASA Mars Exploration Program Office objectives, MRO will be used as a relay communication link for the Mars Science Laboratory (MSL) mission during the MSL Entry, Descent and Landing sequence. To do so, MRO Navigation must synchronize the MRO Primary Science Orbit (PSO) with a set of target conditions requested by the MSL Navigation Team; this may be accomplished via propulsive maneuvers. This paper describes the MRO Navigation strategy for and operational performance of MSL EDL relay telecommunication support.

  11. Differential distribution of the KCl cotransporter KCC2 in thalamic relay and reticular nuclei

    PubMed Central

    Barthó, P.; Payne, J. A.; Freund, T. F.; Acsády, L.

    2009-01-01

    In the thalamus of the rat the reversal potential of GABA-induced anion currents is more negative in relay cells than in neurones of the reticular nucleus (nRt) due to different chloride extrusion mechanisms operating in these cells. The distribution of KCl cotransporter type 2 (KCC2), the major neuronal chloride transporter that may underlie this effect, is unknown in the thalamus. In this study the precise regional and ultrastructural localization of KCC2 was examined in the thalamus using immunocytochemical methods. The neuropil of all relay nuclei was found to display intense KCC2 immunostaining to varying degrees. In sharp contrast, the majority of the nRt was negative for KCC2. In the anterior and dorsal part of the nRt, however, KCC2 immunostaining was similar to relay nuclei and parvalbumin and calretinin were found to colocalize with KCC2. At the ultrastructural level, KCC2 immunoreactivity was mainly located in the extrasynaptic membranes of thick and thin dendrites and the somata of relay cells but was also found in close association with asymmetrical synapses formed by cortical afferents. Quantitative evaluation of KCC2 distribution at the electron microscopic level demonstrated that the density of KCC2 did not correlate with dendritic diameter or synaptic coverage but is 1.7 times higher on perisynaptic membrane surfaces than on extrasynaptic membranes. Our data demonstrate that the regional distribution of KCC2 is compatible with the difference in GABA-A reversal potential between relay and reticular nuclei. At the ultrastructural level, abundant extrasynaptic KCC2 expression will probably play a role in the regulation of extrasynaptic GABA-A receptor-mediated inhibition. PMID:15305865

  12. Chat-Line Interaction and Negative Feedback.

    ERIC Educational Resources Information Center

    Iwasaki, Junko; Oliver, Rhonda

    2003-01-01

    Examines communicative interactions between native speakers (NSs) and nonnative speakers (NNSs) of Japanese on Internet relay chat, with a special focus on implicit negative feedback in the interactions. Reports that NSs of Japanese gave implicit negative feedback to their NNS partners and NNSs used the feedback in their subsequent production, but…

  13. An entangled-LED-driven quantum relay over 1 km

    NASA Astrophysics Data System (ADS)

    Varnava, Christiana; Stevenson, R. Mark; Nilsson, Jonas; Skiba-Szymanska, Joanna; Dzurňák, Branislav; Lucamarini, Marco; Penty, Richard V.; Farrer, Ian; Ritchie, David A.; Shields, Andrew J.

    2016-03-01

    Quantum cryptography allows confidential information to be communicated between two parties, with secrecy guaranteed by the laws of nature alone. However, upholding guaranteed secrecy over networks poses a further challenge, as classical receive-and-resend routing nodes can only be used conditional of trust by the communicating parties, which arguably diminishes the value of the underlying quantum cryptography. Quantum relays offer a potential solution by teleporting qubits from a sender to a receiver, without demanding additional trust from end users. Here we demonstrate the operation of a quantum relay over 1 km of optical fibre, which teleports a sequence of photonic quantum bits to a receiver by utilising entangled photons emitted by a semiconductor light-emitting diode. The average relay fidelity of the link is 0.90±0.03, exceeding the classical bound of 0.75 for the set of states used, and sufficiently high to allow error correction. The fundamentally low multiphoton emission statistics and the integration potential of the source present an appealing platform for future quantum networks.

  14. Simple electronics for inertial and Pan-type piezoelectric positioners used in scanning probe microscopes

    NASA Astrophysics Data System (ADS)

    Chen, LeuJen; Kim, Seong Heon; Lee, Alfred K. H.; de Lozanne, Alex

    2012-01-01

    We describe a new type of circuit designed for driving piezoelectric positioners that rely on the stick-slip phenomenon. The circuit can be used for inertial positioners that have only one piezoelectric element (or multiple elements that are moved simultaneously) or for designs using a sequential movement of independent piezoelectric elements. A relay switches the piezoelectric elements between a high voltage source and ground, thus creating a fast voltage step followed by a slow ramp produced by the exponential discharging of the piezoelectric elements through a series resistor. A timing cascade is generated by having each relay power the next relay in the sequence. This design is simple and inexpensive. While it was developed for scanning probe microscopes, it may be useful for any piezoelectric motor based on a fast jump followed by a slow relaxation.

  15. Staged-Fault Testing of Distance Protection Relay Settings

    NASA Astrophysics Data System (ADS)

    Havelka, J.; Malarić, R.; Frlan, K.

    2012-01-01

    In order to analyze the operation of the protection system during induced fault testing in the Croatian power system, a simulation using the CAPE software has been performed. The CAPE software (Computer-Aided Protection Engineering) is expert software intended primarily for relay protection engineers, which calculates current and voltage values during faults in the power system, so that relay protection devices can be properly set up. Once the accuracy of the simulation model had been confirmed, a series of simulations were performed in order to obtain the optimal fault location to test the protection system. The simulation results were used to specify the test sequence definitions for the end-to-end relay testing using advanced testing equipment with GPS synchronization for secondary injection in protection schemes based on communication. The objective of the end-to-end testing was to perform field validation of the protection settings, including verification of the circuit breaker operation, telecommunication channel time and the effectiveness of the relay algorithms. Once the end-to-end secondary injection testing had been completed, the induced fault testing was performed with three-end lines loaded and in service. This paper describes and analyses the test procedure, consisting of CAPE simulations, end-to-end test with advanced secondary equipment and staged-fault test of a three-end power line in the Croatian transmission system.

  16. High salinity relay as a postharvest processing strategy to reduce vibrio vulnificus levels in Chesapeake Bay oysters (Crassostrea virginica).

    PubMed

    Audemard, Corinne; Kator, Howard I; Rhodes, Martha W; Gallivan, Thomas; Erskine, A J; Leggett, A Thomas; Reece, Kimberly S

    2011-11-01

    In 2009 the U.S. Food and Drug Administration (FDA) announced its intention to implement postharvest processing (PHP) methods to eliminate Vibrio vulnificus from oysters intended for the raw, half-shell market that are harvested from the Gulf of Mexico during warmer months. FDA-approved PHP methods can be expensive and may be associated with unfavorable responses from some consumers. A relatively unexplored PHP method that uses relaying to high salinity waters could be an alternative strategy, considering that high salinities appear to negatively affect the survival of V. vulnificus. During relay, however, oysters may be exposed to rapid and large salinity increases that could cause increased mortality. In this study, the effectiveness of high salinity relay to reduce V. vulnificus to <30 most probable number (MPN) per g and the impact on oyster mortality were assessed in the lower Chesapeake Bay. Two relay experiments were performed during the summer and fall of 2010. Oysters collected from three grow-out sites, a low salinity site (14 to 15 practical salinity units [psu]) and two moderate salinity sites (22 to 25 psu), were relayed directly to a high salinity site (≥30 psu) on Virginia's Eastern Shore. Oysters were assayed for V. vulnificus and Vibrio parahaemolyticus (another Vibrio species of concern) densities at time 0 prior to relay and after 7 and 14 days of relay, using the FDA MPN enrichment method combined with detection by real-time PCR. After 14 days, both V. vulnificus and V. parahaemolyticus densities were ≤0.8 MPN/g, and decreases of 2 to 3 log in V. vulnificus densities were observed. Oyster mortalities were low (≤4%) even for oysters from the low salinity harvest site, which experienced a salinity increase of approximately 15 psu. Results, although preliminary and requiring formal validation and economic analysis, suggest that high salinity relay could be an effective PHP method.

  17. Incremental Structured Dictionary Learning for Video Sensor-Based Object Tracking

    PubMed Central

    Xue, Ming; Yang, Hua; Zheng, Shibao; Zhou, Yi; Yu, Zhenghua

    2014-01-01

    To tackle robust object tracking for video sensor-based applications, an online discriminative algorithm based on incremental discriminative structured dictionary learning (IDSDL-VT) is presented. In our framework, a discriminative dictionary combining both positive, negative and trivial patches is designed to sparsely represent the overlapped target patches. Then, a local update (LU) strategy is proposed for sparse coefficient learning. To formulate the training and classification process, a multiple linear classifier group based on a K-combined voting (KCV) function is proposed. As the dictionary evolves, the models are also trained to timely adapt the target appearance variation. Qualitative and quantitative evaluations on challenging image sequences compared with state-of-the-art algorithms demonstrate that the proposed tracking algorithm achieves a more favorable performance. We also illustrate its relay application in visual sensor networks. PMID:24549252

  18. AutoGen Version 5.0

    NASA Technical Reports Server (NTRS)

    Gladden, Roy E.; Khanampornpan, Teerapat; Fisher, Forest W.

    2010-01-01

    Version 5.0 of the AutoGen software has been released. Previous versions, variously denoted Autogen and autogen, were reported in two articles: Automated Sequence Generation Process and Software (NPO-30746), Software Tech Briefs (Special Supplement to NASA Tech Briefs), September 2007, page 30, and Autogen Version 2.0 (NPO- 41501), NASA Tech Briefs, Vol. 31, No. 10 (October 2007), page 58. To recapitulate: AutoGen (now signifying automatic sequence generation ) automates the generation of sequences of commands in a standard format for uplink to spacecraft. AutoGen requires fewer workers than are needed for older manual sequence-generation processes, and greatly reduces sequence-generation times. The sequences are embodied in spacecraft activity sequence files (SASFs). AutoGen automates generation of SASFs by use of another previously reported program called APGEN. AutoGen encodes knowledge of different mission phases and of how the resultant commands must differ among the phases. AutoGen also provides means for customizing sequences through use of configuration files. The approach followed in developing AutoGen has involved encoding the behaviors of a system into a model and encoding algorithms for context-sensitive customizations of the modeled behaviors. This version of AutoGen addressed the MRO (Mars Reconnaissance Orbiter) primary science phase (PSP) mission phase. On previous Mars missions this phase has more commonly been referred to as mapping phase. This version addressed the unique aspects of sequencing orbital operations and specifically the mission specific adaptation of orbital operations for MRO. This version also includes capabilities for MRO s role in Mars relay support for UHF relay communications with the MER rovers and the Phoenix lander.

  19. Desynchronization of cells on the developmental path triggers the formation of spiral waves of cAMP during Dictyostelium aggregation.

    PubMed

    Lauzeral, J; Halloy, J; Goldbeter, A

    1997-08-19

    Whereas it is relatively easy to account for the formation of concentric (target) waves of cAMP in the course of Dictyostelium discoideum aggregation after starvation, the origin of spiral waves remains obscure. We investigate a physiologically plausible mechanism for the spontaneous formation of spiral waves of cAMP in D. discoideum. The scenario relies on the developmental path associated with the continuous changes in the activity of enzymes such as adenylate cyclase and phosphodiesterase observed during the hours that follow starvation. These changes bring the cells successively from a nonexcitable state to an excitable state in which they relay suprathreshold cAMP pulses, and then to autonomous oscillations of cAMP, before the system returns to an excitable state. By analyzing a model for cAMP signaling based on receptor desensitization, we show that the desynchronization of cells on this developmental path triggers the formation of fully developed spirals of cAMP. Developmental paths that do not correspond to the sequence of dynamic transitions no relay-relay-oscillations-relay are less able or fail to give rise to the formation of spirals.

  20. Desynchronization of cells on the developmental path triggers the formation of spiral waves of cAMP during Dictyostelium aggregation

    PubMed Central

    Lauzeral, Jacques; Halloy, José; Goldbeter, Albert

    1997-01-01

    Whereas it is relatively easy to account for the formation of concentric (target) waves of cAMP in the course of Dictyostelium discoideum aggregation after starvation, the origin of spiral waves remains obscure. We investigate a physiologically plausible mechanism for the spontaneous formation of spiral waves of cAMP in D. discoideum. The scenario relies on the developmental path associated with the continuous changes in the activity of enzymes such as adenylate cyclase and phosphodiesterase observed during the hours that follow starvation. These changes bring the cells successively from a nonexcitable state to an excitable state in which they relay suprathreshold cAMP pulses, and then to autonomous oscillations of cAMP, before the system returns to an excitable state. By analyzing a model for cAMP signaling based on receptor desensitization, we show that the desynchronization of cells on this developmental path triggers the formation of fully developed spirals of cAMP. Developmental paths that do not correspond to the sequence of dynamic transitions no relay-relay-oscillations-relay are less able or fail to give rise to the formation of spirals. PMID:9256451

  1. Relay NBS Graft with the Plus Delivery System to Improve Deployment in Aortic Arch with Small Radius Curve

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ferro, Carlo; Rossi, Umberto G., E-mail: urossi76@hotmail.com; Seitun, Sara

    The purpose of this report is to describe deployment of the Relay NBS Thoracic Stent Graft with the Plus Delivery System (Bolton Medical, Sunrise, FL) in a flexible resin arch model with a 15-mm radius curve as well as our preliminary clinical results. The Relay NBS graft with the Plus Delivery System was evaluated by way of bench testing, which was performed with stent grafts with diameters ranging from 24 to 46 mm and lengths ranging from 100 to 250 mm in flexible resin arch models with a 15-mm arch radius of curvature. The deployment sequence was analyzed. The Relaymore » NBS graft with the Plus Delivery System was deployed in two patients, respectively, having a 6.5-cm penetrating aortic ulcer of the proximal third of the descending thoracic aorta and a DeBakey type-I aortic dissection with chronic false lumen dilatation after surgery due to an entry site at the distal thoracic aorta. Bench tests showed proper conformation and apposition of the Relay NBS graft with the Plus Delivery System in the flexible resin model. This stent graft was deployed successfully into the two patients with a correct orientation of the first stent and without early or late complications. The Relay NBS graft with the Plus Delivery System ensures an optimal conformation and apposition of the first stent in the aortic arch with a small radius of curvature.« less

  2. Prevention of Ca(2+)-mediated action potentials in GABAergic local circuit neurones of rat thalamus by a transient K+ current.

    PubMed Central

    Pape, H C; Budde, T; Mager, R; Kisvárday, Z F

    1994-01-01

    1. Neurones enzymatically dissociated from the rat dorsal lateral geniculate nucleus (LGN) were identified as GABAergic local circuit interneurones and geniculocortical relay cells, based upon quantitative analysis of soma profiles, immunohistochemical detection of GABA or glutamic acid decarboxylase, and basic electrogenic behaviour. 2. During whole-cell current-clamp recording, isolated LGN neurones generated firing patterns resembling those in intact tissue, with the most striking difference relating to the presence in relay cells of a Ca2+ action potential with a low threshold of activation, capable of triggering fast spikes, and the absence of a regenerative Ca2+ response with a low threshold of activation in local circuit cells. 3. Whole-cell voltage-clamp experiments demonstrated that both classes of LGN neurones possess at least two voltage-dependent membrane currents which operate in a range of membrane potentials negative to the threshold for generation of Na(+)-K(+)-mediated spikes: the T-type Ca2+ current (IT) and an A-type K+ current (IA). Taking into account the differences in membrane surface area, the average size of IT was similar in the two types of neurones, and interneurones possessed a slightly larger A-conductance. 4. In local circuit neurones, the ranges of steady-state inactivation and activation of IT and IA were largely overlapping (VH = 81.1 vs. -82.8 mV), both currents activated at around -70 mV, and they rapidly increased in amplitude with further depolarization. In relay cells, the inactivation curve of IT was negatively shifted along the voltage axis by about 20 mV compared with that of IA (Vh = -86.1 vs. -69.2 mV), and the activation threshold for IT (at -80 mV) was 20 mV more negative than that for IA. In interneurones, the activation range of IT was shifted to values more positive than that in relay cells (Vh = -54.9 vs. -64.5 mV), whereas the activation range of IA was more negative (Vh = -25.2 vs. -14.5 mV). 5. Under whole-cell voltage-clamp conditions that allowed the combined activation of Ca2+ and K+ currents, depolarizing voltage steps from -110 mV evoked inward currents resembling IT in relay cells and small outward currents indicative of IA in local circuit neurones. After blockade of IA with 4-aminopyridine (4-AP), the same pulse protocol produced IT in both types of neurones. Under current clamp, 4-AP unmasked a regenerative membrane depolarization with a low threshold of activation capable of triggering fast spikes in local circuit neurones.(ABSTRACT TRUNCATED AT 400 WORDS) Images Figure 1 PMID:7965855

  3. Magnets at Work and Play.

    ERIC Educational Resources Information Center

    Lindsay, Jack

    1991-01-01

    Describes a sequence of activities which explore the nature of magnetism. Presents background information and details for classroom instruction for the following activities: plotting two-dimensional magnetic fields, making the reed switch and the reed relay, building a ribbon and moving coil loudspeaker, and investigations of a toy commutatorless…

  4. Solid state safety jumper cables

    DOEpatents

    Kronberg, James W.

    1993-01-01

    Solid state jumper cables for connecting two batteries in parallel, having two bridge rectifiers for developing a reference voltage, a four-input decoder for determining which terminals are to be connected based on a comparison of the voltage at each of the four terminals to the reference voltage, and a pair of relays for effecting the correct connection depending on the determination of the decoder. No connection will be made unless only one terminal of each battery has a higher voltage than the reference voltage, indicating "positive" terminals, and one has a lower voltage than the reference voltage, indicating "negative" terminals, and that, therefore, the two high voltage terminals may be connected and the two lower voltage terminals may be connected. Current flows once the appropriate relay device is closed. The relay device is preferably a MOSFET (metal oxide semiconductor field effect transistor) combined with a series array of photodiodes that develop MOSFET gate-closing potential when the decoder output causes an LED to light.

  5. Solid state safety jumper cables

    DOEpatents

    Kronberg, J.W.

    1993-02-23

    Solid state jumper cables for connecting two batteries in parallel, having two bridge rectifiers for developing a reference voltage, a four-input decoder for determining which terminals are to be connected based on a comparison of the voltage at each of the four terminals to the reference voltage, and a pair of relays for effecting the correct connection depending on the determination of the decoder. No connection will be made unless only one terminal of each battery has a higher voltage than the reference voltage, indicating positive'' terminals, and one has a lower voltage than the reference voltage, indicating negative'' terminals, and that, therefore, the two high voltage terminals may be connected and the two lower voltage terminals may be connected. Current flows once the appropriate relay device is closed. The relay device is preferably a MOSFET (metal oxide semiconductor field effect transistor) combined with a series array of photodiodes that develop MOSFET gate-closing potential when the decoder output causes an LED to light.

  6. A new modelling and identification scheme for time-delay systems with experimental investigation: a relay feedback approach

    NASA Astrophysics Data System (ADS)

    Pandey, Saurabh; Majhi, Somanath; Ghorai, Prasenjit

    2017-07-01

    In this paper, the conventional relay feedback test has been modified for modelling and identification of a class of real-time dynamical systems in terms of linear transfer function models with time-delay. An ideal relay and unknown systems are connected through a negative feedback loop to bring the sustained oscillatory output around the non-zero setpoint. Thereafter, the obtained limit cycle information is substituted in the derived mathematical equations for accurate identification of unknown plants in terms of overdamped, underdamped, critically damped second-order plus dead time and stable first-order plus dead time transfer function models. Typical examples from the literature are included for the validation of the proposed identification scheme through computer simulations. Subsequently, the comparisons between estimated model and true system are drawn through integral absolute error criterion and frequency response plots. Finally, the obtained output responses through simulations are verified experimentally on real-time liquid level control system using Yokogawa Distributed Control System CENTUM CS3000 set up.

  7. Interaction in Storytelling in Japanese Conversations: An Analysis of Story Recipients' Questions

    ERIC Educational Resources Information Center

    Koike, Chisato

    2009-01-01

    This study investigates how "unknowing" story recipients (C. Goodwin, 1979) use different types of questions in order to actively participate in storytelling and collaboratively construct a story when a storyteller is relaying his or her past experience, by examining grammar, intonation, gaze, body movements, and sequence organization in Japanese…

  8. Low noise charge ramp electrometer

    DOEpatents

    Morgan, John P.; Piper, Thomas C.

    1992-01-01

    An electrometer capable of measuring small currents without the use of a feedback resistor which tends to contribute a large noise factor to the measured data. The electrometer eliminates the feedback resistor through the use of a feedback capacitor located across the electrometer amplifier. The signal from the electrometer amplifier is transferred to a electrometer buffer amplifier which serves to transfer the signal to several receptors. If the electrometer amplifier is approaching saturation, the buffer amplifier signals a reset discriminator which energizes a coil whose magnetic field closes a magnetic relay switch which in turn resets or zeros the feedback capacitor. In turn, a reset complete discriminator restarts the measurement process when the electrometer amplifier approaches its initial condition. The buffer amplifier also transmits the voltage signal from the electrometer amplifier to a voltage-to-frequency converter. The signals from the voltage-to-frequency converter are counted over a fixed period of time and the information is relayed to a data processor. The timing and sequencing of the small current measuring system is under the control of a sequence control logic unit.

  9. Low noise charge ramp electrometer

    DOEpatents

    Morgan, J.P.; Piper, T.C.

    1992-10-06

    An electrometer capable of measuring small currents without the use of a feedback resistor which tends to contribute a large noise factor to the measured data. The electrometer eliminates the feedback resistor through the use of a feedback capacitor located across the electrometer amplifier. The signal from the electrometer amplifier is transferred to a electrometer buffer amplifier which serves to transfer the signal to several receptors. If the electrometer amplifier is approaching saturation, the buffer amplifier signals a reset discriminator which energizes a coil whose magnetic field closes a magnetic relay switch which in turn resets or zeros the feedback capacitor. In turn, a reset complete discriminator restarts the measurement process when the electrometer amplifier approaches its initial condition. The buffer amplifier also transmits the voltage signal from the electrometer amplifier to a voltage-to-frequency converter. The signals from the voltage-to-frequency converter are counted over a fixed period of time and the information is relayed to a data processor. The timing and sequencing of the small current measuring system is under the control of a sequence control logic unit. 2 figs.

  10. Serial DNA relay in DNA logic gates by electrical fusion and mechanical splitting of droplets

    PubMed Central

    Kawano, Ryuji; Takinoue, Masahiro; Osaki, Toshihisa; Kamiya, Koki; Miki, Norihisa

    2017-01-01

    DNA logic circuits utilizing DNA hybridization and/or enzymatic reactions have drawn increasing attention for their potential applications in the diagnosis and treatment of cellular diseases. The compartmentalization of such a system into a microdroplet considerably helps to precisely regulate local interactions and reactions between molecules. In this study, we introduced a relay approach for enabling the transfer of DNA from one droplet to another to implement multi-step sequential logic operations. We proposed electrical fusion and mechanical splitting of droplets to facilitate the DNA flow at the inputs, logic operation, output, and serial connection between two logic gates. We developed Negative-OR operations integrated by a serial connection of the OR gate and NOT gate incorporated in a series of droplets. The four types of input defined by the presence/absence of DNA in the input droplet pair were correctly reflected in the readout at the Negative-OR gate. The proposed approach potentially allows for serial and parallel logic operations that could be used for complex diagnostic applications. PMID:28700641

  11. 78 FR 40407 - Structure and Practices of the Video Relay Service Program: Telecommunications Relay Services and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-05

    ...] Structure and Practices of the Video Relay Service Program: Telecommunications Relay Services and Speech-to... telecommunications relay services (TRS) program continues to offer functional equivalence to all eligible users and... Practices of the Video Relay Service Program; Telecommunications Relay Services and Speech-to-Speech...

  12. Thalamic amplification of cortical connectivity sustains attentional control

    PubMed Central

    Schmitt, L. Ian; Wimmer, Ralf D.; Nakajima, Miho; Happ, Michael; Mofakham, Sima; Halassa, Michael M.

    2017-01-01

    While interactions between the thalamus and cortex are critical for cognitive function1–3, the exact contribution of the thalamus to these interactions is often unclear. Recent studies have shown diverse connectivity patterns across the thalamus 4,5, but whether this diversity translates to thalamic functions beyond relaying information to or between cortical regions6 is unknown. Here, by investigating prefrontal cortical (PFC) representation of two rules used to guide attention, we find that the mediodorsal thalamus (MD) sustains these representations without relaying categorical information. Specifically, MD input amplifies local PFC connectivity, enabling rule-specific neural sequences to emerge and thereby maintain rule representations. Consistent with this notion, broadly enhancing PFC excitability diminishes rule specificity and behavioral performance, while enhancing MD excitability improves both. Overall, our results define a previously unknown principle in neuroscience; thalamic control of functional cortical connectivity. This function indicates that the thalamus plays much more central roles in cognition than previously thought. PMID:28467827

  13. STBC AF relay for unmanned aircraft system

    NASA Astrophysics Data System (ADS)

    Adachi, Fumiyuki; Miyazaki, Hiroyuki; Endo, Chikara

    2015-01-01

    If a large scale disaster similar to the Great East Japan Earthquake 2011 happens, some areas may be isolated from the communications network. Recently, unmanned aircraft system (UAS) based wireless relay communication has been attracting much attention since it is able to quickly re-establish the connection between isolated areas and the network. However, the channel between ground station (GS) and unmanned aircraft (UA) is unreliable due to UA's swing motion and as consequence, the relay communication quality degrades. In this paper, we introduce space-time block coded (STBC) amplify-and-forward (AF) relay for UAS based wireless relay communication to improve relay communication quality. A group of UAs forms single frequency network (SFN) to perform STBC-AF cooperative relay. In STBC-AF relay, only conjugate operation, block exchange and amplifying are required at UAs. Therefore, STBC-AF relay improves the relay communication quality while alleviating the complexity problem at UAs. It is shown by computer simulation that STBC-AF relay can achieve better throughput performance than conventional AF relay.

  14. 78 FR 49717 - Speech-to-Speech and Internet Protocol (IP) Speech-to-Speech Telecommunications Relay Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-15

    ...] Speech-to-Speech and Internet Protocol (IP) Speech-to-Speech Telecommunications Relay Services... Internet Protocol (IP) Speech-to-Speech Telecommunications Relay Services; Telecommunications Relay... (IP Relay) and video relay service (VRS), the Commission should bundle national STS outreach efforts...

  15. 78 FR 40581 - Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-05

    ... Relay Service (IP Relay) providers; Adopts rules to protect the privacy of customer information relating... Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and Speech Disabilities; Final Rule #0;#0;Federal Register...

  16. Performance Analysis of MIMO Relay Network via Propagation Measurement in L-Shaped Corridor Environment

    NASA Astrophysics Data System (ADS)

    Lertwiram, Namzilp; Tran, Gia Khanh; Mizutani, Keiichi; Sakaguchi, Kei; Araki, Kiyomichi

    Setting relays can address the shadowing problem between a transmitter (Tx) and a receiver (Rx). Moreover, the Multiple-Input Multiple-Output (MIMO) technique has been introduced to improve wireless link capacity. The MIMO technique can be applied in relay network to enhance system performance. However, the efficiency of relaying schemes and relay placement have not been well investigated with experiment-based study. This paper provides a propagation measurement campaign of a MIMO two-hop relay network in 5GHz band in an L-shaped corridor environment with various relay locations. Furthermore, this paper proposes a Relay Placement Estimation (RPE) scheme to identify the optimum relay location, i.e. the point at which the network performance is highest. Analysis results of channel capacity show that relaying technique is beneficial over direct transmission in strong shadowing environment while it is ineffective in non-shadowing environment. In addition, the optimum relay location estimated with the RPE scheme also agrees with the location where the network achieves the highest performance as identified by network capacity. Finally, the capacity analysis shows that two-way MIMO relay employing network coding has the best performance while cooperative relaying scheme is not effective due to shadowing effect weakening the signal strength of the direct link.

  17. Diversity Order Analysis of Dual-Hop Relaying with Partial Relay Selection

    NASA Astrophysics Data System (ADS)

    Bao, Vo Nguyen Quoc; Kong, Hyung Yun

    In this paper, we study the performance of dual hop relaying in which the best relay selected by partial relay selection will help the source-destination link to overcome the channel impairment. Specifically, closed-form expressions for outage probability, symbol error probability and achievable diversity gain are derived using the statistical characteristic of the signal-to-noise ratio. Numerical investigation shows that the system achieves diversity of two regardless of relay number and also confirms the correctness of the analytical results. Furthermore, the performance loss due to partial relay selection is investigated.

  18. 47 CFR 74.635 - Unattended operation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Stations § 74.635 Unattended operation. (a) TV relay stations, TV translator relay stations, TV STL... persons; (3) TV relay stations, TV STL stations, TV translator relay stations, and TV microwave booster... control point. Additionally, a TV translator relay station (and any associated TV microwave booster...

  19. Mars Express Forward Link Capabilities for the Mars Relay Operations Service (MaROS)

    NASA Technical Reports Server (NTRS)

    Allard, Daniel A.; Wallick, Michael N.; Gladden, Roy E.; Wang, Paul

    2012-01-01

    This software provides a new capability for landed Mars assets to perform forward link relay through the Mars Express (MEX) European Union orbital spacecraft. It solves the problem of standardizing the relay interface between lander missions and MEX. The Mars Operations Relay Service (MaROS) is intended as a central point for relay planning and post-pass analysis for all Mars landed and orbital assets. Through the first two phases of implementation, MaROS supports relay coordination through the Odyssey orbiter and the Mars Reconnaissance Orbiter (MRO). With this new software, MaROS now fully integrates the Mars Express spacecraft into the relay picture. This new software generates and manages a new set of file formats that allows for relay request to MEX for forward and return link relay, including the parameters specific to MEX. Existing MEX relay planning interactions were performed via email exchanges and point-to-point file transfers. By integrating MEX into MaROS, all transactions are managed by a centralized service for tracking and analysis. Additionally, all lander missions have a single, shared interface with MEX and do not have to integrate on a mission-by mission basis. Relay is a critical element of Mars lander data management. Landed assets depend largely upon orbital relay for data delivery, which can be impacted by the availability and health of each orbiter in the network. At any time, an issue may occur to prevent relay. For this reason, it is imperative that all possible orbital assets be integrated into the overall relay picture.

  20. Great expectations: patient perspectives and anticipated utility of non-diagnostic genomic-sequencing results.

    PubMed

    Hylind, Robyn; Smith, Maureen; Rasmussen-Torvik, Laura; Aufox, Sharon

    2018-01-01

    The management of secondary findings is a challenge to health-care providers relaying clinical genomic-sequencing results to patients. Understanding patients' expectations from non-diagnostic genomic sequencing could help guide this management. This study interviewed 14 individuals enrolled in the eMERGE (Electronic Medical Records and Genomics) study. Participants in eMERGE consent to undergo non-diagnostic genomic sequencing, receive results, and have results returned to their physicians. The interviews assessed expectations and intended use of results. The majority of interviewees were male (64%) and 43% identified as non-Caucasian. A unique theme identified was that many participants expressed uncertainty about the type of diseases they expected to receive results on, what results they wanted to learn about, and how they intended to use results. Participant uncertainty highlights the complex nature of deciding to undergo genomic testing and a deficiency in genomic knowledge. These results could help improve how genomic sequencing and secondary findings are discussed with patients.

  1. Myoblast cytonemes mediate Wg signaling from the wing imaginal disc and Delta-Notch signaling to the air sac primordium.

    PubMed

    Huang, Hai; Kornberg, Thomas B

    2015-05-07

    The flight muscles, dorsal air sacs, wing blades, and thoracic cuticle of the Drosophila adult function in concert, and their progenitor cells develop together in the wing imaginal disc. The wing disc orchestrates dorsal air sac development by producing decapentaplegic and fibroblast growth factor that travel via specific cytonemes in order to signal to the air sac primordium (ASP). Here, we report that cytonemes also link flight muscle progenitors (myoblasts) to disc cells and to the ASP, enabling myoblasts to relay signaling between the disc and the ASP. Frizzled (Fz)-containing myoblast cytonemes take up Wingless (Wg) from the disc, and Delta (Dl)-containing myoblast cytonemes contribute to Notch activation in the ASP. Wg signaling negatively regulates Dl expression in the myoblasts. These results reveal an essential role for cytonemes in Wg and Notch signaling and for a signal relay system in the myoblasts.

  2. Method for pulse control in a laser including a stimulated brillouin scattering mirror system

    DOEpatents

    Dane, C. Brent; Hackel, Lloyd; Harris, Fritz B.

    2007-10-23

    A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

  3. Stimulated Brillouin scattering mirror system, high power laser and laser peening method and system using same

    DOEpatents

    Dane, C Brent [Livermore, CA; Hackel, Lloyd [Livermore, CA; Harris, Fritz B [Rocklin, CA

    2007-04-24

    A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

  4. 49 CFR 236.52 - Relayed cut-section.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Relayed cut-section. 236.52 Section 236.52...: All Systems Track Circuits § 236.52 Relayed cut-section. Where relayed cut-section is used in... shall be open and the track circuit shunted when the track relay at such cut-section is in deenergized...

  5. 49 CFR 236.52 - Relayed cut-section.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Relayed cut-section. 236.52 Section 236.52...: All Systems Track Circuits § 236.52 Relayed cut-section. Where relayed cut-section is used in... shall be open and the track circuit shunted when the track relay at such cut-section is in deenergized...

  6. 47 CFR 64.601 - Definitions and provisions of general applicability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... obtained by a VRS or IP Relay provider that identifies the physical location of an end user. (18... not use such a device, speech-to-speech services, video relay services and non-English relay services.... (26) Video relay service (VRS). A telecommunications relay service that allows people with hearing or...

  7. 47 CFR 64.601 - Definitions and provisions of general applicability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... obtained by a VRS or IP Relay provider that identifies the physical location of an end user. (18... not use such a device, speech-to-speech services, video relay services and non-English relay services.... (26) Video relay service (VRS). A telecommunications relay service that allows people with hearing or...

  8. 47 CFR 64.601 - Definitions and provisions of general applicability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... vocabulary. (18) Registered Location. The most recent information obtained by a VRS or IP Relay provider that... services, video relay services and non-English relay services. TRS supersedes the terms “dual party relay... TRS User's NANP telephone number to his or her end device. (27) Video relay service (VRS). A...

  9. Breaking the Myth That Relay Swimming Is Faster Than Individual Swimming.

    PubMed

    Skorski, Sabrina; Etxebarria, Naroa; Thompson, Kevin G

    2016-04-01

    To investigate if swimming performance is better in a relay race than in the corresponding individual race. The authors analyzed 166 elite male swimmers from 15 nations in the same competition (downloaded from www.swimrankings.net). Of 778 observed races, 144 were Olympic Games performances (2000, 2004, 2012), with the remaining 634 performed in national or international competitions. The races were 100-m (n = 436) and 200-m (n = 342) freestyle events. Relay performance times for the 2nd-4th swimmers were adjusted (+ 0.73 s) to allow for the "flying start." Without any adjustment, mean individual relay performances were significantly faster for the first 50 m and overall time in the 100-m events. Furthermore, the first 100 m of the 200-m relay was significantly faster (P > .001). During relays, swimmers competing in 1st position did not show any difference compared with their corresponding individual performance (P > .16). However, swimmers competing in 2nd-4th relay-team positions demonstrated significantly faster times in the 100-m (P < .001) and first half of the 200-m relays than in their individual events (P < .001, ES: 0.28-1.77). However, when finishing times for 2nd-4th relay team positions were adjusted for the flying start no differences were detected between relay and individual race performance for any event or split time (P > .17). Highly trained swimmers do not swim (or turn) faster in relay events than in their individual races. Relay exchange times account for the difference observed in individual vs relay performance.

  10. The Laser Communications Relay and the Path to the Next Generation Near Earth Relay

    NASA Technical Reports Server (NTRS)

    Israel, David J.

    2015-01-01

    NASA Goddard Space Flight Center is currently developing the Laser Communications Relay Demonstration (LCRD) as a Path to the Next Generation Near Earth Space Communication Network. The current NASA Space Network or Tracking and Data Relay Satellite System is comprised of a constellation of Tracking and Data Relay Satellites (TDRS) in geosynchronous orbit and associated ground stations and operation centers. NASA is currently targeting a next generation of relay capability on orbit in the 2025 timeframe.

  11. Bidirectional automatic release of reserve for low voltage network made with low capacity PLCs

    NASA Astrophysics Data System (ADS)

    Popa, I.; Popa, G. N.; Diniş, C. M.; Deaconu, S. I.

    2018-01-01

    The article presents the design of a bidirectional automatic release of reserve made on two types low capacity programmable logic controllers: PS-3 from Klöckner-Moeller and Zelio from Schneider. It analyses the electronic timing circuits that can be used for making the bidirectional automatic release of reserve: time-on delay circuit and time-off delay circuit (two types). In the paper are present the sequences code for timing performed on the PS-3 PLC, the logical functions for the bidirectional automatic release of reserve, the classical control electrical diagram (with contacts, relays, and time relays), the electronic control diagram (with logical gates and timing circuits), the code (in IL language) made for the PS-3 PLC, and the code (in FBD language) made for Zelio PLC. A comparative analysis will be carried out on the use of the two types of PLC and will be present the advantages of using PLCs.

  12. Some aspects of radical cascade and relay reactions

    PubMed Central

    Quiclet-Sire, Béatrice; Zard, Samir Z.

    2017-01-01

    The ability to create carbon–carbon bonds is at the heart of organic synthesis. Radical processes are particularly apt at creating such bonds, especially in cascade or relay sequences where more than one bond is formed, allowing for a rapid assembly of complex structures. In the present brief overview, examples taken from the authors' laboratory will serve to illustrate the strategic impact of radical-based approaches on synthetic planning. Transformations involving nitrogen-centred radicals, electron transfer from metallic nickel and the reversible degenerative exchange of xanthates will be presented and discussed. The last method has proved to be a particularly powerful tool for the intermolecular creation of carbon–carbon bonds by radical additions even to unactivated alkenes. Various functional groups can be brought into the same molecule in a convergent manner and made to react together in order to further increase the structural complexity. One important benefit of this chemistry is the so-called RAFT/MADIX technology for the manufacture of block copolymers of almost any desired architecture. PMID:28484329

  13. Universal strategies for the DNA-encoding of libraries of small molecules using the chemical ligation of oligonucleotide tags

    PubMed Central

    Litovchick, Alexander; Clark, Matthew A; Keefe, Anthony D

    2014-01-01

    The affinity-mediated selection of large libraries of DNA-encoded small molecules is increasingly being used to initiate drug discovery programs. We present universal methods for the encoding of such libraries using the chemical ligation of oligonucleotides. These methods may be used to record the chemical history of individual library members during combinatorial synthesis processes. We demonstrate three different chemical ligation methods as examples of information recording processes (writing) for such libraries and two different cDNA-generation methods as examples of information retrieval processes (reading) from such libraries. The example writing methods include uncatalyzed and Cu(I)-catalyzed alkyne-azide cycloadditions and a novel photochemical thymidine-psoralen cycloaddition. The first reading method “relay primer-dependent bypass” utilizes a relay primer that hybridizes across a chemical ligation junction embedded in a fixed-sequence and is extended at its 3′-terminus prior to ligation to adjacent oligonucleotides. The second reading method “repeat-dependent bypass” utilizes chemical ligation junctions that are flanked by repeated sequences. The upstream repeat is copied prior to a rearrangement event during which the 3′-terminus of the cDNA hybridizes to the downstream repeat and polymerization continues. In principle these reading methods may be used with any ligation chemistry and offer universal strategies for the encoding (writing) and interpretation (reading) of DNA-encoded chemical libraries. PMID:25483841

  14. Telecommunications Relay Services

    MedlinePlus

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Telecommunications Relay Services On this page: What are telecommunication ... additional information about telecommunication relay services? What are telecommunication relay services? Title IV of the Americans with ...

  15. MaROS Strategic Relay Planning and Coordination Interfaces

    NASA Technical Reports Server (NTRS)

    Allard, Daniel A.

    2010-01-01

    The Mars Relay Operations Service (MaROS) is designed to provide planning and analysis tools in support of ongoing Mars Network relay operations. Strategic relay planning requires coordination between lander and orbiter mission ground data system (GDS) teams to schedule and execute relay communications passes. MaROS centralizes this process, correlating all data relevant to relay coordination to provide a cohesive picture of the relay state. Service users interact with the system through thin-layer command line and web user interface client applications. Users provide and utilize data such as lander view periods of orbiters, Deep Space Network (DSN) antenna tracks, and reports of relay pass performance. Users upload and download relevant relay data via formally defined and documented file structures including some described in Extensible Markup Language (XML). Clients interface with the system via an http-based Representational State Transfer (ReST) pattern using Javascript Object Notation (JSON) formats. This paper will provide a general overview of the service architecture and detail the software interfaces and considerations for interface design.

  16. Comprehensive analysis of conventional land management in privately-owned rangelands of Extremadura (SW Spain)

    NASA Astrophysics Data System (ADS)

    Pulido, Manuel; Herguido, Estela; Francisco Lavado Contador, Joaquín; Schnabel, Susanne; Gómez-Gutiérrez, Álvaro

    2017-04-01

    Extensive grazing is a key factor for the conservation of High Nature Value (HNV) farming systems such as woody rangelands (dehesas or montados) or grasslands (pastizales) in SW Europe. They have been created from clearing the former Mediterranean forest and have been subject to land use and management changes, particularly during recent decades. Environmental and economic consequences of those changes have been scarcely studied so far. In this study, the land management of 10 privately-owned farms (ranging from 200 to 1,000 ha in size) has been analysed from various perspectives: [1] environmental (soil quality, land degradation, tree regeneration, etc.), [2] economic (inputs, outputs, infrastructure and vehicles) and [3] sociodemographic (type of exploitation, generational relay, etc.). Data were obtained through field surveys, aerial image analysis and personal interviews with owners and shepherds. The results showed negative economic consequences (e.g. more expenses on food supply) on farms where soils are more degraded. Approximately 30% of the farms had negative economic balances, compensated by subsidy payments from the European Union. Furthermore, 50% of the samples do not have guaranteed the generational relay. The obtained information is relevant to evaluate the sustainability of these farming systems. However, a larger number of cases is still necessary in order to draw definitive conclusions. Keywords: Dehesas, Land management, Sustainability, Integrated approach

  17. Relay Telecommunications for the Coming Decade of Mars Exploration

    NASA Technical Reports Server (NTRS)

    Edwards, C.; DePaula, R.

    2010-01-01

    Over the past decade, an evolving network of relay-equipped orbiters has advanced our capabilities for Mars exploration. NASA's Mars Global Surveyor, 2001 Mars Odyssey, and Mars Reconnaissance Orbiter (MRO), as well as ESA's Mars Express Orbiter, have provided telecommunications relay services to the 2003 Mars Exploration Rovers, Spirit and Opportunity, and to the 2007 Phoenix Lander. Based on these successes, a roadmap for continued Mars relay services is in place for the coming decade. MRO and Odyssey will provide key relay support to the 2011 Mars Science Laboratory (MSL) mission, including capture of critical event telemetry during entry, descent, and landing, as well as support for command and telemetry during surface operations, utilizing new capabilities of the Electra relay payload on MRO and the Electra-Lite payload on MSL to allow significant increase in data return relative to earlier missions. Over the remainder of the decade a number of additional orbiter and lander missions are planned, representing new orbital relay service providers and new landed relay users. In this paper we will outline this Mars relay roadmap, quantifying relay performance over time, illustrating planned support scenarios, and identifying key challenges and technology infusion opportunities.

  18. Exact outage analysis of the effect of co-channel interference on secured multi-hop relaying networks

    NASA Astrophysics Data System (ADS)

    Quang Nguyen, Sang; Kong, Hyung Yun

    2016-11-01

    In this article, the presence of multi-hop relaying, eavesdropper and co-channel interference (CCI) in the same system model is investigated. Specifically, the effect of CCI on a secured multi-hop relaying network is studied, in which the source communicates with the destination via multi-relay-hopping under the presence of an eavesdropper and CCI at each node. The optimal relay at each cluster is selected to help forward the message from the source to the destination. We apply two relay selection approaches to such a system model, i.e. the optimal relay is chosen based on (1) the maximum channel gain from the transmitter to all relays in the desired cluster and (2) the minimum channel gain from the eavesdropper to all relays in each cluster. For the performance evaluation and comparison, we derived the exact closed form of the secrecy outage probability of the two approaches. That analysis is verified by Monte Carlo simulation. Finally, the effects of the number of hops, the transmit power at the source, relays and the external sources, the distance between the external sources and each node in the system, and the location of the eavesdropper are presented and discussed.

  19. Energy efficient circuit design using nanoelectromechanical relays

    NASA Astrophysics Data System (ADS)

    Venkatasubramanian, Ramakrishnan

    Nano-electromechanical (NEM) relays are a promising class of emerging devices that offer zero off-state leakage and behave like an ideal switch. Recent advances in planar fabrication technology have demonstrated that microelectromechanical (MEMS) scale miniature relays could be manufactured reliably and could be used to build fully functional, complex integrated circuits. The zero leakage operation of relays has renewed the interest in relay based low power logic design. This dissertation explores circuit architectures using NEM relays and NEMS-CMOS heterogeneous integration. Novel circuit topologies for sequential logic, memory, and power management circuits have been proposed taking into consideration the NEM relay device properties and optimizing for energy efficiency and area. In nanoscale electromechanical devices, dispersion forces like Van der Waals' force (vdW) affect the pull-in stability of the relay devices significantly. Verilog-A electromechanical model of the suspended gate relay operating at 1V with a nominal air gap of 5 - 10nm has been developed taking into account all the electrical, mechanical and dispersion effects. This dissertation explores different relay based latch and flip-flop topologies. It has been shown that as few as 4 relay cells could be used to build flip-flops. An integrated voltage doubler based flip flop that improves the performance by 2X by overdriving Vgb has been proposed. Three NEM relay based parallel readout memory bitcell architectures have been proposed that have faster access time, and remove the reliability issues associated with previously reported serial readout architectures. A paradigm shift in design of power switches using NEM relays is proposed. An interesting property of the relay device is that the ON state resistance (Ron) of the NEM relay switch is constant and is insensitive to the gate slew rate. This coupled with infinite OFF state resistance (Roff ) offers significant area and power advantages over CMOS. This dissertation demonstrates NEM relay based charge pump and NEM-CMOS heterogeneous discontinuous conduction mode (DCM) buck regulator and the results are compared against a standard commercial 0.35μm CMOS implementation. It is shown that NEM-CMOS heterogeneous DC-DC converter has an area savings of 60% over CMOS and achieves an overall higher efficiency over CMOS, with a peak efficiency of 94.3% at 100mA. NEM relays offers unprecedented 10X-30X energy efficiency improvement in logic design for low frequency operation and has the potential to break the CMOS efficiency barrier in power electronic circuits as well. The practical aspects of NEM Relay integration are evaluated and algorithms for synthesis and development of large NEM relay based logic circuits are explored.

  20. Exploring Data Sharing Between Geographically Distributed Mobile and Fixed Nodes Supporting Extended Maritime Interdiction Operations (EMIO)

    DTIC Science & Technology

    2008-06-01

    Diablo and LLNL o ITT Mesh, OPAREA TWO: between BP RHIB and BV, and between Sea Fox (USV) and BV o Sky Pilot, OPAREA THREE: between Tachyon ...between Sea Fox (USV) and BV o Sky Pilot, OPAREA THREE: between Tachyon Satellite and Sky Pilot Relay and between Sky Pilot Relay and BV o Wave Relay...between Tachyon Satellite and Sky Pilot Relay and between Sky Pilot Relay and BV o Wave Relay, OPAREA THREE: between BV and Balloon and between

  1. Failure analysis of blistered gold plating on spot welded electrical relays

    NASA Technical Reports Server (NTRS)

    Sokolowski, Witold; O'Donnell, Tim

    1989-01-01

    Gold-plated stainless-steel sideplates, part of a JPL Galileo spacecraft electronic-relay assembly, exhibited blistering after resistance spot welding. Unacceptable relays had heavy nonuniform gold electrodeposited layers with thicknesses 4.5-11.5 microns. SEM and metallographic investigations indicated much higher heat input generated during the resistance spot welding in unacceptable relays. The attributes of acceptable welded relays are contrasted with unacceptable relays; the possible mechanism of laminar formation of polymeric material in the gold plating is discussed; and some recommendations are provided to prevent similar problems.

  2. 75 FR 26701 - Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-12

    ... Services (CTS), Internet Protocol (IP) CTS, IP Relay, and Video Relay Services (VRS), for the 2010-2011... comment on NECA's proposed compensation rates for TRS, STS, CTS, IP CTS, IP Relay, and VRS, for the 2010... interstate traditional TRS; $3.1566 for STS; $1.6951 for CTS and IP CTS; $1.2985 for IP Relay. Based on these...

  3. Relay selection in energy harvesting cooperative networks with rateless codes

    NASA Astrophysics Data System (ADS)

    Zhu, Kaiyan; Wang, Fei

    2018-04-01

    This paper investigates the relay selection in energy harvesting cooperative networks, where the relays harvests energy from the radio frequency (RF) signals transmitted by a source, and the optimal relay is selected and uses the harvested energy to assist the information transmission from the source to its destination. Both source and the selected relay transmit information using rateless code, which allows the destination recover original information after collecting codes bits marginally surpass the entropy of original information. In order to improve transmission performance and efficiently utilize the harvested power, the optimal relay is selected. The optimization problem are formulated to maximize the achievable information rates of the system. Simulation results demonstrate that our proposed relay selection scheme outperform other strategies.

  4. Adaptive transmission based on multi-relay selection and rate-compatible LDPC codes

    NASA Astrophysics Data System (ADS)

    Su, Hualing; He, Yucheng; Zhou, Lin

    2017-08-01

    In order to adapt to the dynamical changeable channel condition and improve the transmissive reliability of the system, a cooperation system of rate-compatible low density parity check (RC-LDPC) codes combining with multi-relay selection protocol is proposed. In traditional relay selection protocol, only the channel state information (CSI) of source-relay and the CSI of relay-destination has been considered. The multi-relay selection protocol proposed by this paper takes the CSI between relays into extra account in order to obtain more chances of collabration. Additionally, the idea of hybrid automatic request retransmission (HARQ) and rate-compatible are introduced. Simulation results show that the transmissive reliability of the system can be significantly improved by the proposed protocol.

  5. Considerations for an Earth Relay Satellite with RF and Optical Trunklines

    NASA Technical Reports Server (NTRS)

    Israel, David J.

    2016-01-01

    Support for user platforms through the use of optical links to geosynchronous relay spacecraft are expected to be part of the future space communications architecture. The European Data Relay Satellite System (EDRS) has its first node, EDRS-A, in orbit. The EDRS architecture includes space-to-space optical links with a Ka-Band feeder link or trunkline. NASA's Laser Communications Relay Demonstration (LCRD) mission, originally baselined to support a space-to-space optical link relayed with an optical trunkline, has added an Radio Frequency (RF) trunkline. The use of an RF trunkline avoids the outages suffered by an optical trunkline due to clouds, but an RF trunkline will be bandwidth limited. A space relay architecture with both RF and optical trunklines could relay critical realtime data, while also providing a high data volume capacity. This paper considers the relay user scenarios that could be supported, and the implications to the space relay system and operations. System trades such as the amount of onboard processing and storage required, the use of link layer switching vs. network layer routing, and the use of Delay/Disruption Tolerant Networking (DTN) are discussed.

  6. Using a micromachined magnetostatic relay in commutating a DC motor

    NASA Technical Reports Server (NTRS)

    Tai, Yu-Chong (Inventor); Wright, John A. (Inventor); Lilienthal, Gerald (Inventor)

    2004-01-01

    A DC motor is commutated by rotating a magnetic rotor to induce a magnetic field in at least one magnetostatic relay in the motor. Each relay is activated in response to the magnetic field to deliver power to at least one corresponding winding connected to the relay. In some cases, each relay delivers power first through a corresponding primary winding and then through a corresponding secondary winding to a common node. Specific examples include a four-pole, three-phase motor in which each relay is activated four times during one rotation of the magnetic rotor.

  7. Performance Analysis of Relay Subset Selection for Amplify-and-Forward Cognitive Relay Networks

    PubMed Central

    Qureshi, Ijaz Mansoor; Malik, Aqdas Naveed; Zubair, Muhammad

    2014-01-01

    Cooperative communication is regarded as a key technology in wireless networks, including cognitive radio networks (CRNs), which increases the diversity order of the signal to combat the unfavorable effects of the fading channels, by allowing distributed terminals to collaborate through sophisticated signal processing. Underlay CRNs have strict interference constraints towards the secondary users (SUs) active in the frequency band of the primary users (PUs), which limits their transmit power and their coverage area. Relay selection offers a potential solution to the challenges faced by underlay networks, by selecting either single best relay or a subset of potential relay set under different design requirements and assumptions. The best relay selection schemes proposed in the literature for amplify-and-forward (AF) based underlay cognitive relay networks have been very well studied in terms of outage probability (OP) and bit error rate (BER), which is deficient in multiple relay selection schemes. The novelty of this work is to study the outage behavior of multiple relay selection in the underlay CRN and derive the closed-form expressions for the OP and BER through cumulative distribution function (CDF) of the SNR received at the destination. The effectiveness of relay subset selection is shown through simulation results. PMID:24737980

  8. A performance analysis in AF full duplex relay selection network

    NASA Astrophysics Data System (ADS)

    Ngoc, Long Nguyen; Hong, Nhu Nguyen; Loan, Nguyen Thi Phuong; Kieu, Tam Nguyen; Voznak, Miroslav; Zdralek, Jaroslav

    2018-04-01

    This paper studies on the relaying selective matter in amplify-and-forward (AF) cooperation communication with full-duplex (FD) activity. Various relay choice models supposing the present of different instant information are investigated. We examine a maximal relaying choice that optimizes the instant FD channel capacity and asks for global channel state information (CSI) as well as partial CSI learning. To make comparison easy, accurate outage probability clauses and asymptote form of these strategies that give a diversity rank are extracted. From that, we can see clearly that the number of relays, noise factor, the transmittance coefficient as well as the information transfer power had impacted on their performance. Besides, the optimal relay selection (ORS) model can promote than that of the partial relay selection (PRS) model.

  9. Relay discovery and selection for large-scale P2P streaming

    PubMed Central

    Zhang, Chengwei; Wang, Angela Yunxian

    2017-01-01

    In peer-to-peer networks, application relays have been commonly used to provide various networking services. The service performance often improves significantly if a relay is selected appropriately based on its network location. In this paper, we studied the location-aware relay discovery and selection problem for large-scale P2P streaming networks. In these large-scale and dynamic overlays, it incurs significant communication and computation cost to discover a sufficiently large relay candidate set and further to select one relay with good performance. The network location can be measured directly or indirectly with the tradeoffs between timeliness, overhead and accuracy. Based on a measurement study and the associated error analysis, we demonstrate that indirect measurements, such as King and Internet Coordinate Systems (ICS), can only achieve a coarse estimation of peers’ network location and those methods based on pure indirect measurements cannot lead to a good relay selection. We also demonstrate that there exists significant error amplification of the commonly used “best-out-of-K” selection methodology using three RTT data sets publicly available. We propose a two-phase approach to achieve efficient relay discovery and accurate relay selection. Indirect measurements are used to narrow down a small number of high-quality relay candidates and the final relay selection is refined based on direct probing. This two-phase approach enjoys an efficient implementation using the Distributed-Hash-Table (DHT). When the DHT is constructed, the node keys carry the location information and they are generated scalably using indirect measurements, such as the ICS coordinates. The relay discovery is achieved efficiently utilizing the DHT-based search. We evaluated various aspects of this DHT-based approach, including the DHT indexing procedure, key generation under peer churn and message costs. PMID:28410384

  10. Relay discovery and selection for large-scale P2P streaming.

    PubMed

    Zhang, Chengwei; Wang, Angela Yunxian; Hei, Xiaojun

    2017-01-01

    In peer-to-peer networks, application relays have been commonly used to provide various networking services. The service performance often improves significantly if a relay is selected appropriately based on its network location. In this paper, we studied the location-aware relay discovery and selection problem for large-scale P2P streaming networks. In these large-scale and dynamic overlays, it incurs significant communication and computation cost to discover a sufficiently large relay candidate set and further to select one relay with good performance. The network location can be measured directly or indirectly with the tradeoffs between timeliness, overhead and accuracy. Based on a measurement study and the associated error analysis, we demonstrate that indirect measurements, such as King and Internet Coordinate Systems (ICS), can only achieve a coarse estimation of peers' network location and those methods based on pure indirect measurements cannot lead to a good relay selection. We also demonstrate that there exists significant error amplification of the commonly used "best-out-of-K" selection methodology using three RTT data sets publicly available. We propose a two-phase approach to achieve efficient relay discovery and accurate relay selection. Indirect measurements are used to narrow down a small number of high-quality relay candidates and the final relay selection is refined based on direct probing. This two-phase approach enjoys an efficient implementation using the Distributed-Hash-Table (DHT). When the DHT is constructed, the node keys carry the location information and they are generated scalably using indirect measurements, such as the ICS coordinates. The relay discovery is achieved efficiently utilizing the DHT-based search. We evaluated various aspects of this DHT-based approach, including the DHT indexing procedure, key generation under peer churn and message costs.

  11. Relay protection features of frequency-adjustable electric drive

    NASA Astrophysics Data System (ADS)

    Kuprienko, V. V.

    2018-03-01

    The features of relay protection of high-voltage electric motors in composition of the frequency-adjustable electric drive are considered in the article. The influence of frequency converters on the stability of the operation of various types of relay protection used on electric motors is noted. Variants of circuits for connecting relay protection devices are suggested. The need to develop special relay protection devices for a frequency-adjustable electric drive is substantiated.

  12. Development of a Relay Performance Web Tool for the Mars Network

    NASA Technical Reports Server (NTRS)

    Allard, Daniel A.; Edwards, Charles D.

    2009-01-01

    Modern Mars surface missions rely upon orbiting spacecraft to relay communications to and from Earth systems. An important component of this multi-mission relay process is the collection of relay performance statistics supporting strategic trend analysis and tactical anomaly identification and tracking.

  13. Modified Dynamic Decode-and-Forward Relaying Protocol for Type II Relay in LTE-Advanced and Beyond

    PubMed Central

    Nam, Sung Sik; Alouini, Mohamed-Slim; Choi, Seyeong

    2016-01-01

    In this paper, we propose a modified dynamic decode-and-forward (MoDDF) relaying protocol to meet the critical requirements for user equipment (UE) relays in next-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed MoDDF realizes the fast jump-in relaying and the sequential decoding with an application of random codeset to encoding and re-encoding process at the source and the multiple UE relays, respectively. A subframe-by-subframe decoding based on the accumulated (or buffered) messages is employed to achieve energy, information, or mixed combining. Finally, possible early termination of decoding at the end user can lead to the higher spectral efficiency and more energy saving by reducing the frequency of redundant subframe transmission and decoding. These attractive features eliminate the need of directly exchanging control messages between multiple UE relays and the end user, which is an important prerequisite for the practical UE relay deployment. PMID:27898712

  14. Modified Dynamic Decode-and-Forward Relaying Protocol for Type II Relay in LTE-Advanced and Beyond.

    PubMed

    Nam, Sung Sik; Alouini, Mohamed-Slim; Choi, Seyeong

    2016-01-01

    In this paper, we propose a modified dynamic decode-and-forward (MoDDF) relaying protocol to meet the critical requirements for user equipment (UE) relays in next-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed MoDDF realizes the fast jump-in relaying and the sequential decoding with an application of random codeset to encoding and re-encoding process at the source and the multiple UE relays, respectively. A subframe-by-subframe decoding based on the accumulated (or buffered) messages is employed to achieve energy, information, or mixed combining. Finally, possible early termination of decoding at the end user can lead to the higher spectral efficiency and more energy saving by reducing the frequency of redundant subframe transmission and decoding. These attractive features eliminate the need of directly exchanging control messages between multiple UE relays and the end user, which is an important prerequisite for the practical UE relay deployment.

  15. Grid Integrated Type 3 Wind Systems - Modeling, and Line Protection Performance Analysis using the RTDS

    NASA Astrophysics Data System (ADS)

    Jain, Rishabh

    In this thesis, the line protection elements and their supervisory elements are analyzed in context of Type 3 (Doubly Fed Induction Generator based) grid integrated wind turbine systems. The underlying converter and controller design algorithms and topologies are discussed. A detailed controller for the Type 3 wind turbine system is designed and integrated to the grid using the RTDS. An alternative to the conventional PLL for tracking of rotor frequency is designed and implemented. A comparative analysis of the performance of an averaged model and the corresponding switching model is presented. After completing the WT model design, the averaged model is used to model an aggregate 10-generator equivalent model tied to a 230kV grid via a 22kV collector. This model is a great asset to understand dynamics, and the unfaulted and faulted behavior of aggregated and single-turbine Type 3 WT systems. The model is then utilized to analyze the response of conventional protection schemes (Line current Differential and Mho Distance elements) and their respective supervisory elements of modern commercial protection relays in real time by hardware-in-the-loop simulation using the RTDS. Differences in the behavior of these elements compared to conventional power systems is noted. Fault are analyzed from the relay's perspective and the reasons for the observed behavior are presented. Challenges associated with sequence components and relay sensitivity are discussed and alternate practices to circumvent these issues are recommended.

  16. Fuzzy logic based on-line fault detection and classification in transmission line.

    PubMed

    Adhikari, Shuma; Sinha, Nidul; Dorendrajit, Thingam

    2016-01-01

    This study presents fuzzy logic based online fault detection and classification of transmission line using Programmable Automation and Control technology based National Instrument Compact Reconfigurable i/o (CRIO) devices. The LabVIEW software combined with CRIO can perform real time data acquisition of transmission line. When fault occurs in the system current waveforms are distorted due to transients and their pattern changes according to the type of fault in the system. The three phase alternating current, zero sequence and positive sequence current data generated by LabVIEW through CRIO-9067 are processed directly for relaying. The result shows that proposed technique is capable of right tripping action and classification of type of fault at high speed therefore can be employed in practical application.

  17. Relay Selection for Cooperative Relaying in Wireless Energy Harvesting Networks

    NASA Astrophysics Data System (ADS)

    Zhu, Kaiyan; Wang, Fei; Li, Songsong; Jiang, Fengjiao; Cao, Lijie

    2018-01-01

    Energy harvesting from the surroundings is a promising solution to provide energy supply and extend the life of wireless sensor networks. Recently, energy harvesting has been shown as an attractive solution to prolong the operation of cooperative networks. In this paper, we propose a relay selection scheme to optimize the amplify-and-forward (AF) cooperative transmission in wireless energy harvesting cooperative networks. The harvesting energy and channel conditions are considered to select the optimal relay as cooperative relay to minimize the outage probability of the system. Simulation results show that our proposed relay selection scheme achieves better outage performance than other strategies.

  18. Sparsity-aware multiple relay selection in large multi-hop decode-and-forward relay networks

    NASA Astrophysics Data System (ADS)

    Gouissem, A.; Hamila, R.; Al-Dhahir, N.; Foufou, S.

    2016-12-01

    In this paper, we propose and investigate two novel techniques to perform multiple relay selection in large multi-hop decode-and-forward relay networks. The two proposed techniques exploit sparse signal recovery theory to select multiple relays using the orthogonal matching pursuit algorithm and outperform state-of-the-art techniques in terms of outage probability and computation complexity. To reduce the amount of collected channel state information (CSI), we propose a limited-feedback scheme where only a limited number of relays feedback their CSI. Furthermore, a detailed performance-complexity tradeoff investigation is conducted for the different studied techniques and verified by Monte Carlo simulations.

  19. A microcomputer-based testing station for dynamic and static testing of protective relay systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, W.J.; Li, R.J.; Gu, J.C.

    1995-12-31

    Dynamic and static relay performance testing before installation in the field is a subject of great interest to utility relay engineers. The common practice in utility testing of new relays is to put the new unit to be tested in parallel with an existing functioning relay in the system, wait until an actual transient occurs and then observe and analyze the performance of new relay. It is impossible to have a thorough test of the protective relay system through this procedure. An equipment, Microcomputer-Based Testing Station (or PC-Based Testing Station), that can perform both static and dynamic testing of themore » relay is described in this paper. The Power System Simulation Laboratory at the University of Texas at Arlington is a scaled-down, three-phase, physical power system which correlates well with the important components for a real power system and is an ideal facility for the dynamic and static testing of protective relay systems. A brief introduction to the configuration of this laboratory is presented. Test results of several protective functions by using this laboratory illustrate the usefulness of this test set-up.« less

  20. Relay exchanges in elite short track speed skating.

    PubMed

    Hext, Andrew; Heller, Ben; Kelley, John; Goodwill, Simon

    2017-06-01

    In short track speed skating, the relay exchange provides an additional strategic component to races by allowing a team to change the skater involved in the pack race. Typically executed every 1½ laps, it is the belief of skaters and coaches that during this period of the race, time can be gained or lost due to the execution of the relay exchange. As such, the aim of this study was to examine the influence of the relay exchange on a team's progression through a 5000 m relay race. Using data collected from three World Cup relay events during the 2012-2013 season, the time taken to complete the straight for the scenarios with and without the relay exchange were compared at different skating speeds for the corner exit prior to the straight. Overall, the influence of the relay exchange was found to be dependent on this corner exit speed. At slower corner exit speeds (12.01-13.5 m/s), relay exchange straight times were significantly faster than the free skating scenario (P < 0.01). While at faster corner exit speeds (14.01-15 m/s), straight times were significantly slower (P < 0.001). The findings of this study suggest that the current norm of executing relay exchanges every 1½ laps may not be optimal. Instead, varying the frequency of relay exchange execution throughout the race could allow: (1) time to be gained relative to other teams; and (2) facilitate other race strategies by providing an improved opportunity to overtake.

  1. 47 CFR 90.243 - Mobile relay stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Mobile relay stations. 90.243 Section 90.243... MOBILE RADIO SERVICES Non-Voice and Other Specialized Operations § 90.243 Mobile relay stations. (a) Mobile relay operations will be authorized on frequencies below 512 MHz, except in the Radiolocation...

  2. 49 CFR 236.589 - Relays.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.589 Relays. (a) Each relay shall be removed... train stop or train control system, at least once every two years; and (2) All other relays, at least...

  3. 49 CFR 236.589 - Relays.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.589 Relays. (a) Each relay shall be removed... train stop or train control system, at least once every two years; and (2) All other relays, at least...

  4. 76 FR 59551 - Internet-Based Telecommunications Relay Service Numbering

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ..., and IP Relay, which allows these individuals to communicate in text using a computer. The final rules... hearing and speech disabilities to communicate using sign language through video equipment, and IP Relay... language through video equipment, and IP Relay, which allows these individuals to communicate in text using...

  5. 78 FR 55249 - Transmission Relay Loadability Reliability Standard; Notice of Compliance Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-10

    ...; RM11-16-000] Transmission Relay Loadability Reliability Standard; Notice of Compliance Filing Take.... \\1\\ Transmission Relay Loadability Reliability Standard, Order No. 733, 130 FERC ] 61, 221 (2010..., Order No. 733-B, 136 FERC ] 61,185 (2011). \\2\\ Transmission Relay Loadability Reliability Standard, 138...

  6. 78 FR 21929 - Transmission Relay Loadability Reliability Standard; Notice of Compliance Filing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-12

    ... Relay Loadability Reliability Standard; Notice of Compliance Filing Take notice that on February 19... Relay Loadability Reliability Standard, Order No. 733, 130 FERC ] 61,221 (2010) (Order No. 733); order..., 136 FERC ] 61,185 (2011). \\2\\ Transmission Relay Loadability Reliability Standard, 138 FERC ] 61,197...

  7. 76 FR 44326 - Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-25

    ... Relay Services and Speech-to-Speech Services for Individuals With Hearing and Speech Disabilities; Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION...-minute video relay service (``VRS'') compensation rates, and adopts per-minute compensation rates for the...

  8. How to Use Telecommunications Relay Service. NETAC Teacher Tipsheet

    ERIC Educational Resources Information Center

    Mothersell, Mary Beth, Comp.

    1999-01-01

    Telecommunications Relay Service provides full telephone accessibility to people who are deaf, hard of hearing, deaf-blind, or speech-disabled. Specially trained Communication Assistants (CAs) serve as intermediaries, relaying conversations between hearing persons and persons using a text telephone device (TTY). Relay Service is available 24 hours…

  9. 75 FR 41863 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-19

    ... Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Notice. SUMMARY: In this document, the Commission takes a fresh look at its video relay service (VRS) rules so that the Commission.... SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Structure and Practices of the Video Relay...

  10. 76 FR 68642 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Final rule... with the Commission's Structure and Practices of the Video Relay Service Program, Memorandum Opinion... effective date of these rule sections. See, In the Matter of Structure and Practices of the Video Relay...

  11. 76 FR 68328 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-04

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Final rule... with the Commission's Structure and Practices of the Video Relay Service Program, Second Report and... effective date of these rule sections. See, In the Matter of Structure and Practices of the Video Relay...

  12. 76 FR 8659 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Final rule... with the Commission's Structure and Practices of the Video Relay Service Program, Declaratory Ruling... Practices of the Video Relay Service Program, CG Docket No. 10-51. Form Number: N/A. Respondents: Business...

  13. 75 FR 51735 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-23

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. [[Page 51736... to detect and prevent fraud and misuse in the provision of Video Relay Service (VRS). Because the VRS... is a summary of the Commission's Structure and Practices of the Video Relay Service Program, Notice...

  14. 76 FR 58424 - Transmission Relay Loadability Reliability Standard

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... Protection Systems 2. Protective relays are devices that detect and initiate the removal of faults [[Page... protective relay detects a fault on an element of the system under its protection, it sends a signal to an... distribution providers to set load-responsive phase protection relays according to specific criteria to ensure...

  15. 76 FR 24442 - Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ...] Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and Speech Disabilities AGENCY: Federal Communications Commission. ACTION: Proposed rule. SUMMARY: In this document, the Commission tentatively concludes that it...

  16. PI3K Phosphorylation Is Linked to Improved Electrical Excitability in an In Vitro Engineered Heart Tissue Disease Model System.

    PubMed

    Kana, Kujaany; Song, Hannah; Laschinger, Carol; Zandstra, Peter W; Radisic, Milica

    2015-09-01

    Myocardial infarction, a prevalent cardiovascular disease, is associated with cardiomyocyte cell death, and eventually heart failure. Cardiac tissue engineering has provided hopes for alternative treatment options, and high-fidelity tissue models for drug discovery. The signal transduction mechanisms relayed in response to mechanoelectrical (physical) stimulation or biochemical stimulation (hormones, cytokines, or drugs) in engineered heart tissues (EHTs) are poorly understood. In this study, an EHT model was used to elucidate the signaling mechanisms involved when insulin was applied in the presence of electrical stimulation, a stimulus that mimics functional heart tissue environment in vitro. EHTs were insulin treated, electrically stimulated, or applied in combination (insulin and electrical stimulation). Electrical excitability parameters (excitation threshold and maximum capture rate) were measured. Protein kinase B (AKT) and phosphatidylinositol-3-kinase (PI3K) phosphorylation revealed that insulin and electrical stimulation relayed electrical excitability through two separate signaling cascades, while there was a negative crosstalk between sustained activation of AKT and PI3K.

  17. 78 FR 49693 - Speech-to-Speech and Internet Protocol (IP) Speech-to-Speech Telecommunications Relay Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-15

    ...] Speech-to-Speech and Internet Protocol (IP) Speech-to-Speech Telecommunications Relay Services...: This is a summary of the Commission's Speech-to-Speech and Internet Protocol (IP) Speech-to-Speech...), Internet Protocol Relay (IP Relay), and IP captioned telephone service (IP CTS) as compensable forms of TRS...

  18. The History and Development of the California Relay Service.

    ERIC Educational Resources Information Center

    Schultz, Stephen

    1990-01-01

    The California Relay Services (CRS) is a statewide 24-hour dual-party relay system which is designed to bridge the communication gap between the hearing-impaired and the normal-hearing community by using communication assistants to relay calls between those without Telecommunication Devices for the Deaf (TDDs) and TDD-users. (DB)

  19. 78 FR 63152 - Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ...] Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and Speech Disabilities... for telecommunications relay services (TRS) by eliminating standards for Internet-based relay services... comments, identified by CG Docket No. 03-123, by any of the following methods: Electronic Filers: Comments...

  20. Versatile solid-state relay

    NASA Technical Reports Server (NTRS)

    Fox, D. A.

    1977-01-01

    Solid-state relay (SSR), containing multinode control logic, is operated as normally open, normally closed, or latched. Moreover several can be paralleled to form two-pole or double-throw relays. Versatile unit ends need to design custom control circuit for every relay application. Technique can be extended to incorporate selectable time delay, on operation or release, or pulsed output.

  1. 77 FR 43538 - Misuse of Internet Protocol (IP) Relay Service; Telecommunications Relay Services and Speech-to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ... the Internet, this service has become subject to abuse. Among other things, persons have been using IP...] Misuse of Internet Protocol (IP) Relay Service; Telecommunications Relay Services and Speech-to-Speech.... ACTION: Final rule. SUMMARY: In this document, the Commission adopts a measure that prohibits Internet...

  2. Cross-layer Joint Relay Selection and Power Allocation Scheme for Cooperative Relaying System

    NASA Astrophysics Data System (ADS)

    Zhi, Hui; He, Mengmeng; Wang, Feiyue; Huang, Ziju

    2018-03-01

    A novel cross-layer joint relay selection and power allocation (CL-JRSPA) scheme over physical layer and data-link layer is proposed for cooperative relaying system in this paper. Our goal is finding the optimal relay selection and power allocation scheme to maximize system achievable rate when satisfying total transmit power constraint in physical layer and statistical delay quality-of-service (QoS) demand in data-link layer. Using the concept of effective capacity (EC), our goal can be formulated into an optimal joint relay selection and power allocation (JRSPA) problem to maximize the EC when satisfying total transmit power limitation. We first solving optimal power allocation (PA) problem with Lagrange multiplier approach, and then solving optimal relay selection (RS) problem. Simulation results demonstrate that CL-JRSPA scheme gets larger EC than other schemes when satisfying delay QoS demand. In addition, the proposed CL-JRSPA scheme achieves the maximal EC when relay located approximately halfway between source and destination, and EC becomes smaller when the QoS exponent becomes larger.

  3. Wireless Energy Harvesting Two-Way Relay Networks with Hardware Impairments.

    PubMed

    Peng, Chunling; Li, Fangwei; Liu, Huaping

    2017-11-13

    This paper considers a wireless energy harvesting two-way relay (TWR) network where the relay has energy-harvesting abilities and the effects of practical hardware impairments are taken into consideration. In particular, power splitting (PS) receiver is adopted at relay to harvests the power it needs for relaying the information between the source nodes from the signals transmitted by the source nodes, and hardware impairments is assumed suffered by each node. We analyze the effect of hardware impairments [-20]on both decode-and-forward (DF) relaying and amplify-and-forward (AF) relaying networks. By utilizing the obtained new expressions of signal-to-noise-plus-distortion ratios, the exact analytical expressions of the achievable sum rate and ergodic capacities for both DF and AF relaying protocols are derived. Additionally, the optimal power splitting (OPS) ratio that maximizes the instantaneous achievable sum rate is formulated and solved for both protocols. The performances of DF and AF protocols are evaluated via numerical results, which also show the effects of various network parameters on the system performance and on the OPS ratio design.

  4. The noncoding human genome and the future of personalised medicine.

    PubMed

    Cowie, Philip; Hay, Elizabeth A; MacKenzie, Alasdair

    2015-01-30

    Non-coding cis-regulatory sequences act as the 'eyes' of the genome and their role is to perceive, organise and relay cellular communication information to RNA polymerase II at gene promoters. The evolution of these sequences, that include enhancers, silencers, insulators and promoters, has progressed in multicellular organisms to the extent that cis-regulatory sequences make up as much as 10% of the human genome. Parallel evidence suggests that 75% of polymorphisms associated with heritable disease occur within predicted cis-regulatory sequences that effectively alter the 'perception' of cis-regulatory sequences or render them blind to cell communication cues. Cis-regulatory sequences also act as major functional targets of epigenetic modification thus representing an important conduit through which changes in DNA-methylation affects disease susceptibility. The objectives of the current review are (1) to describe what has been learned about identifying and characterising cis-regulatory sequences since the sequencing of the human genome; (2) to discuss their role in interpreting cell signalling pathways pathways; and (3) outline how this role may be altered by polymorphisms and epigenetic changes. We argue that the importance of the cis-regulatory genome for the interpretation of cellular communication pathways cannot be overstated and understanding its role in health and disease will be critical for the future development of personalised medicine.

  5. Commercial grade item (CGI) dedication of MDR relays for nuclear safety related applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Das, R.K.; Julka, A.; Modi, G.

    1994-08-01

    MDR relays manufactured by Potter and Brumfield (P and B) have been used in various safety related applications in commercial nuclear power plants. These include emergency safety features (ESF) actuation systems, emergency core cooling systems (ECCS) actuation, and reactor protection systems. The MDR relays manufactured prior to May 1990 showed signs of generic failure due to corrosion and outgassing of coil varnish. P and B has made design changes to correct these problems in relays manufactured after May 1990. However, P and B does not manufacture the relays under any 10CFR50 Appendix B quality assurance (QA) program. They manufacture themore » relays under their commercial QA program and supply these as commercial grade items. This necessitates CGI Dedication of these relays for use in nuclear-safety-related applications. This paper presents a CGI dedication program that has been used to dedicate the MDR relays manufactured after May 1990. The program is in compliance with current Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) guidelines and applicable industry standards; it specifies the critical characteristics of the relays, provides the tests and analysis required to verify the critical characteristics, the acceptance criteria for the test results, performs source verification to qualify P and B for its control of the critical characteristics, and provides documentation. The program provides reasonable assurance that the new MDR relays will perform their intended safety functions.« less

  6. Novel Material Integration for Reliable and Energy-Efficient NEM Relay Technology

    NASA Astrophysics Data System (ADS)

    Chen, I.-Ru

    Energy-efficient switching devices have become ever more important with the emergence of ubiquitous computing. NEM relays are promising to complement CMOS transistors as circuit building blocks for future ultra-low-power information processing, and as such have recently attracted significant attention from the semiconductor industry and researchers. Relay technology potentially can overcome the energy efficiency limit for conventional CMOS technology due to several key characteristics, including zero OFF-state leakage, abrupt switching behavior, and potentially very low active energy consumption. However, two key issues must be addressed for relay technology to reach its full potential: surface oxide formation at the contacting surfaces leading to increased ON-state resistance after switching, and high switching voltages due to strain gradient present within the relay structure. This dissertation advances NEM relay technology by investigating solutions to both of these pressing issues. Ruthenium, whose native oxide is conductive, is proposed as the contacting material to improve relay ON-state resistance stability. Ruthenium-contact relays are fabricated after overcoming several process integration challenges, and show superior ON-state resistance stability in electrical measurements and extended device lifetime. The relay structural film is optimized via stress matching among all layers within the structure, to provide lower strain gradient (below 10E-3/microm -1) and hence lower switching voltage. These advancements in relay technology, along with the integration of a metallic interconnect layer, enable complex relay-based circuit demonstration. In addition to the experimental efforts, this dissertation theoretically analyzes the energy efficiency limit of a NEM switch, which is generally believed to be limited by the surface adhesion energy. New compact (<1 microm2 footprint), low-voltage (<0.1 V) switch designs are proposed to overcome this limit. The results pave a pathway to scaled energy-efficient electronic device technology.

  7. High salinity relay as a post-harvest processing method for reducing Vibrio vulnificus levels in oysters (Crassostrea virginica).

    PubMed

    Audemard, Corinne; Kator, Howard I; Reece, Kimberly S

    2018-08-20

    High salinity relay of Eastern oysters (Crassostrea virginica) was evaluated as a post-harvest processing (PHP) method for reducing Vibrio vulnificus. This approach relies on the exposure of oysters to natural high salinity waters and preserves a live product compared to previously approved PHPs. Although results of prior studies evaluating high salinity relay as a means to decrease V. vulnificus levels were promising, validation of this method as a PHP following approved guidelines is required. This study was designed to provide data for validation of this method following Food and Drug Administration (FDA) PHP validation guidelines. During each of 3 relay experiments, oysters cultured from 3 different Chesapeake Bay sites of contrasting salinities (10-21 psu) were relayed without acclimation to high salinity waters (31-33 psu) for up to 28 days. Densities of V. vulnificus and densities of total and pathogenic Vibrio parahaemolyticus (as tdh positive strains) were measured using an MPN-quantitative PCR approach. Overall, 9 lots of oysters were relayed with 6 exhibiting initial V. vulnificus >10,000/g. As recommended by the FDA PHP validation guidelines, these lots reached both the 3.52 log reduction and the <30 MPN/g densities requirements for V. vulnificus after 14 to 28 days of relay. Densities of total and pathogenic V. parahaemolyticus in relayed oysters were significantly lower than densities at the sites of origin suggesting an additional benefit associated with high salinity relay. While relay did not have a detrimental effect on oyster condition, oyster mortality levels ranged from 2 to 61% after 28 days of relay. Although the identification of the factors implicated in oyster mortality will require further examination, this study strongly supports the validation of high salinity relay as an effective PHP method to reduce levels of V. vulnificus in oysters to endpoint levels approved for human consumption. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Varying Success of Relaying To Reduce Vibrio parahaemolyticus Levels in Oysters ( Crassostrea virginica).

    PubMed

    Taylor, Michael A; Yu, Jong W; Howell, Thomas L; Jones, Stephen H

    2018-04-01

    Vibrio parahaemolyticus is the leading cause of seafood-borne human infections in the United States, and many of these illnesses are associated with consumption of raw molluscan shellfish. V. parahaemolyticus levels in shellfish vary temporally and spatially with environmental conditions in and around production areas. The objective of this study was to study the potential for reducing levels of V. parahaemolyticus in live oysters by relaying them during higher-risk warm weather to a site with elevated salinity and consistently low V. parahaemolyticus levels. The effectiveness of relaying was assessed by analyzing oyster samples collected on days 0, 2, 7, 10, and 14 for V. parahaemolyticus levels using a three-tube most-probable-number enrichment method in conjunction with genetic marker-based quantitative PCR. The salinity at the relay site was always higher than the salinity at the harvest site, with the difference between the two sites ranging from 3.4 to 19.1 ppt (average, 12 ppt) during 2011 to 2014. Oysters relayed during June, July, and August in 2011 and 2012 showed consistently reduced V. parahaemolyticus levels after 14 days, whereas relaying was less successful and V. parahaemolyticus populations changed to include trh-positive strains during 2013. When effective, relay required at least 10 days to reduce V. parahaemolyticus levels. A sample of oysters collected in August 2012, which was temperature abused to increase initial V. parahaemolyticus levels, showed a 4.5-log decrease in V. parahaemolyticus levels after 14 days of relay. These results suggest that relaying oysters to reduce V. parahaemolyticus levels holds promise, but that both microbial community and environmental conditions at relay sites can affect relay success. Further investigation to discover key factors that affect V. parahaemolyticus levels in relayed oysters may aid in developing a consistent approach for reducing V. parahaemolyticus in oysters to eliminate the risk of illness for oyster consumers.

  9. Joint Europa Mission (JEM) : A multi-scale study of Europa to characterize its habitability and search for life.

    NASA Astrophysics Data System (ADS)

    Blanc, Michel; Prieto Ballesteros, Olga; Andre, Nicolas; Cooper, John F.

    2017-04-01

    Europa is the closest and probably the most promising target to perform a comprehensive characterization of habitability and search for extant life. We propose that NASA and ESA join forces to design an ambitious planetary mission we call JEM (for Joint Europa Mission) to reach this objective. JEM will be assigned the following overarching goal: Understand Europa as a complex system responding to Jupiter system forcing, characterize the habitability of its potential biosphere, and search for life in its surface, sub-surface and exosphere. Our observation strategy to address these goals will combine three scientific measurement sequences: measurements on a high-latitude, low-latitude Europan orbit providing a continuous and global mapping of planetary fields (magnetic and gravity) and of the neutral and charged environment during a period of three months; in-situ measurements at the surface, using a soft lander operating during 35 days, to search for bio-signatures at the surface and sub-surface and operate a geophysical station; measurements of the chemical composition of the very low exosphere and plumes in search for biomolecules. The implementation of these three observation sequences will rest on the combination of two science platforms equipped with the most advanced instrumentation: a soft lander to perform all scientific measurements at the surface and sub-surface at a selected landing site, and a carrier/relay/orbiter to perform the orbital survey and descent sequences. In this concept, the orbiter will perform science operations during the relay phase on a carefully optimized halo orbit of the Europa-Jupiter system before moving to its final Europan orbit. The design of both orbiter and lander instruments will have to accommodate the very challenging radiation mitigation and Planetary Protection issues. The proposed lander science platform is composed of a geophysical station and of two complementary astrobiology facilities dedicated to bio-signature characterization experiments operating respectively in the solid and in the liquid phases, fed by a common articulated arm. The "Astrobiology Wet Laboratory" will be a specific European contribution. We propose an innovative distribution of roles to make JEM an appealing and affordable joint venture for the two agencies: while NASA would provide an SLS launcher, the lander stack and mission operations, ESA would provide the carrier-orbiter-relay platform. The delivery of the orbiter by ESA could take advantage of a double European heritage: an adaptation of the ORION ESM bus to JEM, complemented by avionics derived from JUICE.

  10. 75 FR 54040 - Telecommunications Relay Services and Speech-to-Speech Services for Individuals With Hearing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... Services (TRS) mandatory minimum standards for Video Relay Service (VRS) and Internet Protocol Relay (IP... waivers for one year because the record demonstrates that it is technologically infeasible for VRS and IP... standards for VRS and IP Relay will expire on July 1, 2011, or until the Commission addresses pending...

  11. 47 CFR 64.606 - VRS and IP Relay provider and TRS program certification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false VRS and IP Relay provider and TRS program... Services and Related Customer Premises Equipment for Persons With Disabilities § 64.606 VRS and IP Relay... including notification in the Federal Register. (2) VRS and IP Relay provider. Any entity desiring to...

  12. 49 CFR 236.206 - Battery or power supply with respect to relay; location.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Battery or power supply with respect to relay..., AND APPLIANCES Automatic Block Signal Systems Standards § 236.206 Battery or power supply with respect to relay; location. The battery or power supply for each signal control relay circuit, where an open...

  13. 49 CFR 236.206 - Battery or power supply with respect to relay; location.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Battery or power supply with respect to relay..., AND APPLIANCES Automatic Block Signal Systems Standards § 236.206 Battery or power supply with respect to relay; location. The battery or power supply for each signal control relay circuit, where an open...

  14. 49 CFR 236.206 - Battery or power supply with respect to relay; location.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Battery or power supply with respect to relay..., AND APPLIANCES Automatic Block Signal Systems Standards § 236.206 Battery or power supply with respect to relay; location. The battery or power supply for each signal control relay circuit, where an open...

  15. 49 CFR 236.206 - Battery or power supply with respect to relay; location.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Battery or power supply with respect to relay..., AND APPLIANCES Automatic Block Signal Systems Standards § 236.206 Battery or power supply with respect to relay; location. The battery or power supply for each signal control relay circuit, where an open...

  16. 49 CFR 236.206 - Battery or power supply with respect to relay; location.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Battery or power supply with respect to relay..., AND APPLIANCES Automatic Block Signal Systems Standards § 236.206 Battery or power supply with respect to relay; location. The battery or power supply for each signal control relay circuit, where an open...

  17. Relay Support for the Mars Science Laboratory and the Coming Decade of Mars Relay Network Evolution

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D., Jr.; Arnold, Bradford W.; Bell, David J.; Bruvold, Kristoffer N.; Gladden, Roy E.; Ilott, Peter A.; Lee, Charles H.

    2012-01-01

    Mars Relay Network is prepared to support MSL: a) ODY/MRO/MEX will all provide critical event comm support during EDL. b) New Electra/Electra-Lite capabilities on the MSL-MRO link will support >250 Mb/sol MSL data return. 2013 MAVEN orbiter will replenish on-orbit relay infrastructure as prior orbiters approach end-of-life. While NASA has withdrawn from the 2016 EMTGO and 2018 Joint Rover missions, analysis of the potential link shows a path to Gbit/sol relay capability 2012.

  18. Adenylyl cyclase A mRNA localized at the back of cells is actively translated in live chemotaxing Dictyostelium.

    PubMed

    Wang, Weiye; Chen, Song; Das, Satarupa; Losert, Wolfgang; Parent, Carole A

    2018-05-04

    Dictyostelium discoideum cells transport adenylyl cyclase A (ACA)-containing vesicles to the back of polarized cells to relay exogenous cAMP signals during chemotaxis. Fluorescence in situ hybridization (FISH) experiments showed that ACA mRNA is also asymmetrically distributed at the back of polarized cells. By using the MS2 bacteriophage system, we now visualize the distribution of ACA mRNA in live chemotaxing cells. We found that the ACA mRNA localization is not dependent on the translation of the protein product and requires multiple cis-acting elements within the ACA-coding sequence. We show that ACA mRNA is associated with actively translating ribosomes and is transported along microtubules towards the back of cells. By monitoring the recovery of ACA-YFP after photobleaching, we observed that local translation of ACA-YFP occurs at the back of cells. These data represent a novel functional role for localized translation in the relay of chemotactic signals during chemotaxis. © 2018. Published by The Company of Biologists Ltd.

  19. Multiantenna Relay Beamforming Design for QoS Discrimination in Two-Way Relay Networks

    PubMed Central

    Xiong, Ke; Zhang, Yu; Li, Dandan; Zhong, Zhangdui

    2013-01-01

    This paper investigates the relay beamforming design for quality of service (QoS) discrimination in two-way relay networks. The purpose is to keep legitimate two-way relay users exchange their information via a helping multiantenna relay with QoS guarantee while avoiding the exchanged information overhearing by unauthorized receiver. To this end, we propose a physical layer method, where the relay beamforming is jointly designed with artificial noise (AN) which is used to interfere in the unauthorized user's reception. We formulate the joint beamforming and AN (BFA) design into an optimization problem such that the received signal-to-interference-ratio (SINR) at the two legitimate users is over a predefined QoS threshold while limiting the received SINR at the unauthorized user which is under a certain secure threshold. The objective of the optimization problem is to seek the optimal AN and beamforming vectors to minimize the total power consumed by the relay node. Since the optimization problem is nonconvex, we solve it by using semidefinite program (SDP) relaxation. For comparison, we also study the optimal relay beamforming without using AN (BFO) under the same QoS discrimination constraints. Simulation results show that both the proposed BFA and BFO can achieve the QoS discrimination of the two-way transmission. However, the proposed BFA yields significant power savings and lower infeasible rates compared with the BFO method. PMID:24391459

  20. Implementation of a Relay Coordination System for the Mars Network

    NASA Technical Reports Server (NTRS)

    Allard, Daniel A.

    2010-01-01

    Mars network relay operations involve the coordination of lander and orbiter teams through long-term and short-term planning, tactical changes and post-pass analysis. Much of this coordination is managed through email traffic and point-to-point file data exchanges. It is often difficult to construct a complete and accurate picture of the relay situation at any given moment, as there is no centralized store of correlated relay data. The Mars Relay Operations Service (MaROS) is being implemented to address the problem of relay coordination for current and next-generation relay missions. The service is provided for the purpose of coordinating communications sessions between landed spacecraft assets and orbiting spacecraft assets at Mars. The service centralizes a set of functions previously distributed across multiple spacecraft operations teams, and as such greatly improves visibility into the end-to-end strategic coordination process. Most of the process revolves around the scheduling of communications sessions between the spacecraft during periods of time when a landed asset on Mars is geometrically visible by an orbiting spacecraft. These "relay" sessions are used to transfer data both to and from the landed asset via the orbiting asset on behalf of Earth-based spacecraft operators. This paper will discuss the relay coordination problem space, overview the architecture and design selected to meet system requirements, and describe the first phase of system implementation

  1. 49 CFR 236.101 - Purpose of inspection and tests; removal from service of relay or device failing to meet test...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .../or equipment is maintained in condition to perform its intended function. Electronic device, relay... service of relay or device failing to meet test requirements. 236.101 Section 236.101 Transportation Other... Inspections and Tests; All Systems § 236.101 Purpose of inspection and tests; removal from service of relay or...

  2. 49 CFR 234.247 - Purpose of inspections and tests; removal from service of relay or device failing to meet test...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... operations over the grade crossing resume. (c) Any electronic device, relay, or other electromagnetic device... service of relay or device failing to meet test requirements. 234.247 Section 234.247 Transportation Other... Inspections and Tests § 234.247 Purpose of inspections and tests; removal from service of relay or device...

  3. Mobile User Connectivity in Relay-Assisted Visible Light Communications.

    PubMed

    Pešek, Petr; Zvanovec, Stanislav; Chvojka, Petr; Bhatnagar, Manav R; Ghassemlooy, Zabih; Saxena, Prakriti

    2018-04-07

    In this paper, we investigate relay-assisted visible light communications (VLC) where a mobile user acts as a relay and forwards data from a transmitter to the end mobile user. We analyse the utilization of the amplify-and-forward (AF) and decode-and-forward (DF) relaying schemes. The focus of the paper is on analysis of the behavior of the mobile user acting as a relay while considering a realistic locations of the receivers and transmitters on a standard mobile phone, more specifically with two photodetectors on both sides of a mobile phone and a transmitting LED array located upright. We also investigate dependency of the bit error rate (BER) performance on the azimuth and elevation angles of the mobile relay device within a typical office environment. We provide a new analytical description of BER for AF and DF-based relays in VLC. In addition we compare AF and DF-based systems and show that DF offers a marginal improvement in the coverage area with a BER < 10 -3 and a data rate of 100 Mb/s. Numerical results also illustrate that relay-based systems offer a significant improvement in terms of the coverage compared to direct non-line of sight VLC links.

  4. Mobile User Connectivity in Relay-Assisted Visible Light Communications

    PubMed Central

    Pešek, Petr; Zvanovec, Stanislav; Chvojka, Petr; Bhatnagar, Manav R.; Ghassemlooy, Zabih; Saxena, Prakriti

    2018-01-01

    In this paper, we investigate relay-assisted visible light communications (VLC) where a mobile user acts as a relay and forwards data from a transmitter to the end mobile user. We analyse the utilization of the amplify-and-forward (AF) and decode-and-forward (DF) relaying schemes. The focus of the paper is on analysis of the behavior of the mobile user acting as a relay while considering a realistic locations of the receivers and transmitters on a standard mobile phone, more specifically with two photodetectors on both sides of a mobile phone and a transmitting LED array located upright. We also investigate dependency of the bit error rate (BER) performance on the azimuth and elevation angles of the mobile relay device within a typical office environment. We provide a new analytical description of BER for AF and DF-based relays in VLC. In addition we compare AF and DF-based systems and show that DF offers a marginal improvement in the coverage area with a BER < 10–3 and a data rate of 100 Mb/s. Numerical results also illustrate that relay-based systems offer a significant improvement in terms of the coverage compared to direct non-line of sight VLC links. PMID:29642432

  5. Performance Analysis of Amplify-and-Forward Systems with Single Relay Selection in Correlated Environments.

    PubMed

    Van Nguyen, Binh; Kim, Kiseon

    2016-09-11

    In this paper, we consider amplify-and-forward (AnF) cooperative systems under correlated fading environments. We first present a brief overview of existing works on the effect of channel correlations on the system performance. We then focus on our main contribution which is analyzing the outage probability of a multi-AnF-relay system with the best relay selection (BRS) scheme under a condition that two channels of each relay, source-relay and relay-destination channels, are correlated. Using lower and upper bounds on the end-to-end received signal-to-noise ratio (SNR) at the destination, we derive corresponding upper and lower bounds on the system outage probability. We prove that the system can achieve a diversity order (DO) equal to the number of relays. In addition, and importantly, we show that the considered correlation form has a constructive effect on the system performance. In other words, the larger the correlation coefficient, the better system performance. Our analytic results are corroborated by extensive Monte-Carlo simulations.

  6. Performance Evaluation of Relay Selection Schemes in Beacon-Assisted Dual-Hop Cognitive Radio Wireless Sensor Networks under Impact of Hardware Noises.

    PubMed

    Hieu, Tran Dinh; Duy, Tran Trung; Dung, Le The; Choi, Seong Gon

    2018-06-05

    To solve the problem of energy constraints and spectrum scarcity for cognitive radio wireless sensor networks (CR-WSNs), an underlay decode-and-forward relaying scheme is considered, where the energy constrained secondary source and relay nodes are capable of harvesting energy from a multi-antenna power beacon (PB) and using that harvested energy to forward the source information to the destination. Based on the time switching receiver architecture, three relaying protocols, namely, hybrid partial relay selection (H-PRS), conventional opportunistic relay selection (C-ORS), and best opportunistic relay selection (B-ORS) protocols are considered to enhance the end-to-end performance under the joint impact of maximal interference constraint and transceiver hardware impairments. For performance evaluation and comparison, we derive the exact and asymptotic closed-form expressions of outage probability (OP) and throughput (TP) to provide significant insights into the impact of our proposed protocols on the system performance over Rayleigh fading channel. Finally, simulation results validate the theoretical results.

  7. Wideband propagation measurement system using spread spectrum signaling and TDRS

    NASA Technical Reports Server (NTRS)

    Jenkins, Jeffrey D.; Fan, Yiping; Osborne, William P.

    1995-01-01

    In this paper, a wideband propagation measurement system, which consisted of a ground-based transmitter, a mobile receiver, and a data acquisition system, was constructed. This system has been employed in a study of the characteristics of different propagation environments, such as urban, suburban and rural areas, by using a pseudonoise spreading sequence transmitted over NASA's Tracking and Data Relay Satellite System. The hardware and software tests showed that it met overall system requirements and it was very robust during a 3-month-long outdoor data collection experiment.

  8. RADIATION WAVE DETECTOR

    DOEpatents

    Wouters, L.F.

    1958-10-28

    The detection of the shape and amplitude of a radiation wave is discussed, particularly an apparatus for automatically indicating at spaced lntervals of time the radiation intensity at a flxed point as a measure of a radiation wave passing the point. The apparatus utilizes a number of photomultiplier tubes surrounding a scintillation type detector, For obtainlng time spaced signals proportional to radiation at predetermined intervals the photolnultiplier tubes are actuated ln sequence following detector incidence of a predetermined radiation level by electronic means. The time spaced signals so produced are then separately amplified and relayed to recording means.

  9. The effect of tectonic evolution on lacustrine syn-rift sediment patters in Qikou Sag, Bohaiwan Basin, eastern China

    NASA Astrophysics Data System (ADS)

    Liao, Y.; Wang, H.; Xu, W.

    2013-12-01

    Normal fault arrays and associated relay ramps between two overlapping en-echelon normal faults are well known to control the deposition and distribution of sediments in alluvial, fluvial and deltaic systems in rift settings. The influence of transfer zones or relay ramps on sediment routes and dispersal patterns in subaqueous (deeper marine/lacustrine), however, is barely studied and hence less clear. Previous experimental studies indicate that subaqueous relay ramps may act as sediment transportation pathways if certain conditions are available. In this study, we integrate detailed structural and stratigraphic analysis with three-dimensional seismic data and limited well log data from the Qikou Sag to examine the tectonic evolution and the syn-rift sediment patterns response to fault growth and linkage in an active rift setting. Qikou Sag is located at the center of Huanghua Depression, Bohaiwan Basin of eastern China. Structurally, it is a typical continental rift basin characterized by a linked system of two NEE-SWW-striking half-grabens and one E-W-striking graben. Qikou sag is filled with Eocene-Oligocene syn-rift sediments and Miocene to Quaternary post-rift sediments. The Eocene-Oligocene rifting stage can be divided into early rifting period (43-36.5 Ma, the third member and second member of Shahejie Formation, Es3 and Es2), stable rifting period (36.5-29Ma, the first member of Shaehejie Formation, Es1) and fault-depressed diversionary period (29-24.6Ma, the Dongying Formation, Ed). This study focus on the early syn-rift, the third and second member of Shehejie Formation, which is mostly dark-grey mudstone interbedded with fine to coarse-grained sandstone deposited by large-scale turbidity currents in deep-lake. In particular, we use a combination of thickness variability and facies distributions, onlap patterns within a high-resolution sequence stratigraphic framework, integrated with structural geometry, fault activity and subsidence history analysis to investigate the degree of tectonic control on subaqueous sediment transportation and dispersal. Specific attention is paid to deposits close to boundary faults-Gangxi fault, Gangdong fault and Binhai fault and associated relay ramp. Our studies show that significant amount of sediments were deposited on the basin floor close to boundary faults hanging-wall, which were derived from Cangxian uplift and might have originated from channel overspill or flow shedding across the faults. However, minor deposits occurred adjacent to and at the foot of relay ramp, suggesting an influence of these topography features on sediment routing, with the intrabasinal structural high-Beidagang buried hill acting as an additional sediment source. Therefore, the substantial differences between subaerial and subaqueous systems may influence the role of relay ramps in controlling the sediment routes and deposition in Qikou Sag. The attempt to depict subaqueous syn-rift sediment dispersal and relate them with relay ramps is needed to consider the interplay of various factors such as sediment provenience, tectonic activity, ramp geometry, and base level fluctuations in the future investigation.

  10. Optimum satellite relay positions with application to a TDRS-1 Indian Ocean relay

    NASA Technical Reports Server (NTRS)

    Jackson, A. H.; Christopher, P.

    1994-01-01

    An Indian Ocean satellite relay is examined. The relay satellite position is optimized by minimizing the sum of downlink and satellite to satellite link losses. Osculating orbital elements are used for fast intensive orbital computation. Integrated Van Vleck gaseous attenuation and a Crane rain model are used for downlink attenuation. Circular polarization losses on the satellite to satellite link are found dynamically. Space to ground link antenna pointing losses are included as a function of yaw ans spacecraft limits. Relay satellite positions between 90 to 100 degrees East are found attractive for further study.

  11. Telecommunications Relay Services

    MedlinePlus

    ... services? Title IV of the Americans with Disabilities Act (ADA) of 1990 (which took full effect on July 26, 1993) requires all U.S. telephone companies to provide telecommunications relay services. A telecommunications relay ...

  12. Next-Generation NASA Earth-Orbiting Relay Satellites: Fusing Optical and Microwave Communications

    NASA Technical Reports Server (NTRS)

    Israel, David J.; Shaw, Harry

    2018-01-01

    NASA is currently considering architectures and concepts for the generation of relay satellites that will replace the Tracking and Data Relay Satellite (TDRS) constellation, which has been flying since 1983. TDRS-M, the last of the second TDRS generation, launched in August 2017, extending the life of the TDRS constellation beyond 2030. However, opportunities exist to re-engineer the concepts of geosynchronous Earth relay satellites. The needs of the relay satellite customers have changed dramatically over the last 34 years since the first TDRS launch. There is a demand for greater bandwidth as the availability of the traditional RF spectrum for space communications diminishes and the demand for ground station access grows. The next generation of NASA relay satellites will provide for operations that have factored in these new constraints. In this paper, we describe a heterogeneous constellation of geosynchronous relay satellites employing optical and RF communications. The new constellation will enable new optical communications services formed by user-to-space relay, space relay-to-space relay and space relay-to-ground links. It will build upon the experience from the Lunar Laser Communications Demonstration from 2013 and the Laser Communications Relay Demonstration to be launched in 2019.Simultaneous to establishment of the optical communications space segment, spacecraft in the TDRS constellation will be replaced with RF relay satellites with targeted subsets of the TDRS capabilities. This disaggregation of the TDRS service model will allow for flexibility in replenishing the needs of legacy users as well as addition of new capabilities for future users. It will also permit the U.S. government access to launch capabilities such as rideshare and to hosted payloads that were not previously available.In this paper, we also explore how the next generation of Earth relay satellites provides a significant boost in the opportunities for commercial providers to the communications space segment. For optical communications, the backbone of this effort is adoption of commercial technologies from the terrestrial high-bandwidth telecommunications industry into optical payloads. For RF communications, the explosion of software-defined radio, high-speed digital signal processing technologies and networking from areas such as 5G multicarrier will be important. Future commercial providers will not be limited to a small set of large aerospace companies. Ultimately, entirely government-owned and -operated satellite communications will phase out and make way for commercial business models that satisfy NASA's satellite communications requirements. The competition being provided by new entrants in the space communications business may result in a future in which all NASA communications needs can be satisfied commercially.

  13. Next-Generation NASA Earth-Orbiting Relay Satellites: Fusing Microwave and Optical Communications

    NASA Technical Reports Server (NTRS)

    Israel, David J.

    2018-01-01

    NASA is currently considering architectures and concepts for the generation of relay satellites that will replace the Tracking and Data Relay Satellite (TDRS) constellation, which has been flying since 1983. TDRS-M, the last of the second TDRS generation, launched in August 2017, extending the life of the TDRS constellation beyond 2030. However, opportunities exist to re-engineer the concepts of geosynchronous Earth relay satellites. The needs of the relay satellite customers have changed dramatically over the last 34 years since the first TDRS launch. There is a demand for greater bandwidth as the availability of the traditional RF spectrum for space communications diminishes and the demand for ground station access grows. The next generation of NASA relay satellites will provide for operations that have factored in these new constraints. In this paper, we describe a heterogeneous constellation of geosynchronous relay satellites employing optical and RF communications. The new constellation will enable new optical communications services formed by user-to-space relay, space relay-to-space relay and space relay-to-ground links. It will build upon the experience from the Lunar Laser Communications Demonstration from 2013 and the Laser Communications Relay Demonstration to be launched in 2019.Simultaneous to establishment of the optical communications space segment, spacecraft in the TDRS constellation will be replaced with RF relay satellites with targeted subsets of the TDRS capabilities. This disaggregation of the TDRS service model will allow for flexibility in replenishing the needs of legacy users as well as addition of new capabilities for future users. It will also permit the U.S. government access to launch capabilities such as rideshare and to hosted payloads that were not previously available. In this paper, we also explore how the next generation of Earth relay satellites provides a significant boost in the opportunities for commercial providers to the communications space segment. For optical communications, the backbone of this effort is adoption of commercial technologies from the terrestrial high-bandwidth telecommunications industry into optical payloads. For RF communications, the explosion of software-defined radio, high-speed digital signal processing technologies and networking from areas such as 5G multicarrier will be important. Future commercial providers will not be limited to a small set of large aerospace companies. Ultimately, entirely government-owned and -operated satellite communications will phase out and make way for commercial business models that satisfy NASAs satellite communications requirements. The competition being provided by new entrants in the space communications business may result in a future in which all NASA communications needs can be satisfied commercially.

  14. Reliability Analysis of Differential Relay as Main Protection Transformer Using Fuzzy Logic Algorithm

    NASA Astrophysics Data System (ADS)

    Mulyadi, Y.; Sucita, T.; Sumarto; Alpani, M.

    2018-02-01

    Electricity supply demand is increasing every year. It makes PT. PLN (Persero) is required to provide optimal customer service and satisfaction. Optimal service depends on the performance of the equipment of the power system owned, especially the transformer. Power transformer is an electrical equipment that transforms electricity from high voltage to low voltage or vice versa. However, in the electrical power system, is inseparable from interference included in the transformer. But, the disturbance can be minimized by the protection system. The main protection transformer is differential relays. Differential relays working system using Kirchoff law where inflows equal outflows. If there are excessive currents that interfere then the relays will work. But, the relay can also experience decreased performance. Therefore, this final project aims to analyze the reliability of the differential relay on the transformer in three different substations. Referring to the standard applied by the transmission line protection officer, the differential relay shall have slope characteristics of 30% in the first slope and 80% in the second slope when using two slopes and 80% when using one slope with an instant time and the corresponding ratio. So, the results obtained on the Siemens differential release have a reliable slope characteristic with a value of 30 on the fuzzy logic system. In a while, ABB a differential relay is only 80% reliable because two experiments are not reliable. For the time, all the differential relays are instant with a value of 0.06 on the fuzzy logic system. For ratios, the differential relays ABB have a better value than others brand with a value of 151 on the fuzzy logic system.

  15. Relay communications strategies for Mars exploration through 2020

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D., Jr.; Arnold, B.; DePaula, R.; Kazz, G.; Lee, C.; Noreen, G.

    2005-01-01

    In this paper we will examine NASA's strategy for relay communications support of missions planned for this decade, and discuss options for longer-term relay network evolution in support of second-decade missions.

  16. Noncoherent Physical-Layer Network Coding with FSK Modulation: Relay Receiver Design Issues

    DTIC Science & Technology

    2011-03-01

    222 IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 59, NO. 9, SEPTEMBER 2011 2595 Noncoherent Physical-Layer Network Coding with FSK Modulation: Relay... noncoherent reception, channel estima- tion. I. INTRODUCTION IN the two-way relay channel (TWRC), a pair of sourceterminals exchange information...2011 4. TITLE AND SUBTITLE Noncoherent Physical-Layer Network Coding with FSK Modulation:Relay Receiver Design Issues 5a. CONTRACT NUMBER 5b

  17. Simultaneous energy harvesting and information processing in wireless multiple relays with multiple antennas

    NASA Astrophysics Data System (ADS)

    Albaaj, Azhar; Makki, S. Vahab A.; Alabkhat, Qassem; Zahedi, Abdulhamid

    2017-07-01

    Wireless networks suffer from battery discharging specially in cooperative communications when multiple relays have an important role but they are energy constrained. To overcome this problem, energy harvesting from radio frequency signals is applied to charge the node battery. These intermediate nodes have the ability to harvest energy from the source signal and use the energy harvested to transmit information to the destination. In fact, the node tries to harvest energy and then transmit the data to destination. Division of energy harvesting and data transmission can be done in two algorithms: time-switching-based relaying protocol and power-splitting-based relaying protocol. These two algorithms also can be applied in delay-limited and delay-tolerant transmission systems. The previous works have assumed a single relay for energy harvesting, but in this article, the proposed method is concentrated on improving the outage probability and throughput by using multiple antennas in each relay node instead of using single antenna. According to our simulation results, when using multi-antenna relays, ability of energy harvesting is increased and thus system performance will be improved to great extent. Maximum ratio combining scheme has been used when the destination chooses the best signal of relays and antennas satisfying the required signal-to-noise ratio.

  18. Multiple-access relaying with network coding: iterative network/channel decoding with imperfect CSI

    NASA Astrophysics Data System (ADS)

    Vu, Xuan-Thang; Renzo, Marco Di; Duhamel, Pierre

    2013-12-01

    In this paper, we study the performance of the four-node multiple-access relay channel with binary Network Coding (NC) in various Rayleigh fading scenarios. In particular, two relay protocols, decode-and-forward (DF) and demodulate-and-forward (DMF) are considered. In the first case, channel decoding is performed at the relay before NC and forwarding. In the second case, only demodulation is performed at the relay. The contributions of the paper are as follows: (1) two joint network/channel decoding (JNCD) algorithms, which take into account possible decoding error at the relay, are developed in both DF and DMF relay protocols; (2) both perfect channel state information (CSI) and imperfect CSI at receivers are studied. In addition, we propose a practical method to forward the relays error characterization to the destination (quantization of the BER). This results in a fully practical scheme. (3) We show by simulation that the number of pilot symbols only affects the coding gain but not the diversity order, and that quantization accuracy affects both coding gain and diversity order. Moreover, when compared with the recent results using DMF protocol, our proposed DF protocol algorithm shows an improvement of 4 dB in fully interleaved Rayleigh fading channels and 0.7 dB in block Rayleigh fading channels.

  19. The Physical Layer Security Experiments of Cooperative Communication System with Different Relay Behaviors.

    PubMed

    Su, Yishan; Han, Guangyao; Fu, Xiaomei; Xu, Naishen; Jin, Zhigang

    2017-04-06

    Physical layer security is an attractive security mechanism, which exploits the randomness characteristics of wireless transmission channel to achieve security. However, it is hampered by the limitation of the channel condition that the main channel must be better than the eavesdropper channel. To alleviate the limitation, cooperative communication is introduced. Few studies have investigated the physical layer security of the relay transmission model. In this paper, we performed some experiments to evaluate the physical layer security of a cooperative communication system, with a relay operating in decode-and-forward (DF) cooperative mode, selfish and malicious behavior in real non-ideal transmission environment. Security performance is evaluated in terms of the probability of non-zero secrecy capacity. Experiments showed some different results compared to theoretical simulation: (1) to achieve the maximum secrecy capacity, the optimal relay power according to the experiments result is larger than that of ideal theoretical results under both cooperative and selfish behavior relay; (2) the relay in malicious behavior who forwards noise to deteriorate the main channel may deteriorate the eavesdropper channel more seriously than the main channel; (3) the optimal relay positions under cooperative and selfish behavior relay cases are both located near the destination because of non-ideal transmission.

  20. The broadcast classical-quantum capacity region of a two-phase bidirectional relaying channel

    NASA Astrophysics Data System (ADS)

    Boche, Holger; Cai, Minglai; Deppe, Christian

    2015-10-01

    We studied a three-node quantum network that enables bidirectional communication between two nodes with a half-duplex relay node for transmitting classical messages. A decode-and-forward protocol is used to perform the communication in two phases. In the first phase, the messages of two nodes are transmitted to the relay node. The capacity of the first phase is well known by previous works. In the second phase, the relay node broadcasts a re-encoded composition to the two nodes. We determine the capacity region of the broadcast phase. To the best of our knowledge, this is the first paper analyzing quantum bidirectional relay networks.

  1. Phospholipase C-beta4 is essential for the progression of the normal sleep sequence and ultradian body temperature rhythms in mice.

    PubMed

    Ikeda, Masayuki; Hirono, Moritoshi; Sugiyama, Takashi; Moriya, Takahiro; Ikeda-Sagara, Masami; Eguchi, Naomi; Urade, Yoshihiro; Yoshioka, Tohru

    2009-11-09

    THE SLEEP SEQUENCE: i) non-REM sleep, ii) REM sleep, and iii) wakefulness, is stable and widely preserved in mammals, but the underlying mechanisms are unknown. It has been shown that this sequence is disrupted by sudden REM sleep onset during active wakefulness (i.e., narcolepsy) in orexin-deficient mutant animals. Phospholipase C (PLC) mediates the signaling of numerous metabotropic receptors, including orexin receptors. Among the several PLC subtypes, the beta4 subtype is uniquely localized in the geniculate nucleus of thalamus which is hypothesized to have a critical role in the transition and maintenance of sleep stages. In fact, we have reported irregular theta wave frequency during REM sleep in PLC-beta4-deficient mutant (PLC-beta4-/-) mice. Daily behavioral phenotypes and metabotropic receptors involved have not been analyzed in detail in PLC-beta4-/- mice, however. Therefore, we analyzed 24-h sleep electroencephalogram in PLC-beta4-/- mice. PLC-beta4-/- mice exhibited normal non-REM sleep both during the day and nighttime. PLC-beta4-/- mice, however, exhibited increased REM sleep during the night, their active period. Also, their sleep was fragmented with unusual wake-to-REM sleep transitions, both during the day and nighttime. In addition, PLC-beta4-/- mice reduced ultradian body temperature rhythms and elevated body temperatures during the daytime, but had normal homeothermal response to acute shifts in ambient temperatures (22 degrees C-4 degrees C). Within the most likely brain areas to produce these behavioral phenotypes, we found that, not orexin, but group-1 metabotropic glutamate receptor (mGluR)-mediated Ca(2+) mobilization was significantly reduced in the dorsal lateral geniculate nucleus (LGNd) of PLC-beta4-/- mice. Voltage clamp recordings revealed that group-1 mGluR-mediated currents in LGNd relay neurons (inward in wild-type mice) were outward in PLC-beta4-/- mice. These lines of evidence indicate that impaired LGNd relay, possibly mediated via group-1 mGluR, may underlie irregular sleep sequences and ultradian body temperature rhythms in PLC-beta4-/- mice.

  2. Outage Performance Analysis of Relay Selection Schemes in Wireless Energy Harvesting Cooperative Networks over Non-Identical Rayleigh Fading Channels †

    PubMed Central

    Do, Nhu Tri; Bao, Vo Nguyen Quoc; An, Beongku

    2016-01-01

    In this paper, we study relay selection in decode-and-forward wireless energy harvesting cooperative networks. In contrast to conventional cooperative networks, the relays harvest energy from the source’s radio-frequency radiation and then use that energy to forward the source information. Considering power splitting receiver architecture used at relays to harvest energy, we are concerned with the performance of two popular relay selection schemes, namely, partial relay selection (PRS) scheme and optimal relay selection (ORS) scheme. In particular, we analyze the system performance in terms of outage probability (OP) over independent and non-identical (i.n.i.d.) Rayleigh fading channels. We derive the closed-form approximations for the system outage probabilities of both schemes and validate the analysis by the Monte-Carlo simulation. The numerical results provide comprehensive performance comparison between the PRS and ORS schemes and reveal the effect of wireless energy harvesting on the outage performances of both schemes. Additionally, we also show the advantages and drawbacks of the wireless energy harvesting cooperative networks and compare to the conventional cooperative networks. PMID:26927119

  3. Outage Performance Analysis of Relay Selection Schemes in Wireless Energy Harvesting Cooperative Networks over Non-Identical Rayleigh Fading Channels.

    PubMed

    Do, Nhu Tri; Bao, Vo Nguyen Quoc; An, Beongku

    2016-02-26

    In this paper, we study relay selection in decode-and-forward wireless energy harvesting cooperative networks. In contrast to conventional cooperative networks, the relays harvest energy from the source's radio-frequency radiation and then use that energy to forward the source information. Considering power splitting receiver architecture used at relays to harvest energy, we are concerned with the performance of two popular relay selection schemes, namely, partial relay selection (PRS) scheme and optimal relay selection (ORS) scheme. In particular, we analyze the system performance in terms of outage probability (OP) over independent and non-identical (i.n.i.d.) Rayleigh fading channels. We derive the closed-form approximations for the system outage probabilities of both schemes and validate the analysis by the Monte-Carlo simulation. The numerical results provide comprehensive performance comparison between the PRS and ORS schemes and reveal the effect of wireless energy harvesting on the outage performances of both schemes. Additionally, we also show the advantages and drawbacks of the wireless energy harvesting cooperative networks and compare to the conventional cooperative networks.

  4. Performance Analysis of Amplify-and-Forward Systems with Single Relay Selection in Correlated Environments

    PubMed Central

    Nguyen, Binh Van; Kim, Kiseon

    2016-01-01

    In this paper, we consider amplify-and-forward (AnF) cooperative systems under correlated fading environments. We first present a brief overview of existing works on the effect of channel correlations on the system performance. We then focus on our main contribution which is analyzing the outage probability of a multi-AnF-relay system with the best relay selection (BRS) scheme under a condition that two channels of each relay, source-relay and relay-destination channels, are correlated. Using lower and upper bounds on the end-to-end received signal-to-noise ratio (SNR) at the destination, we derive corresponding upper and lower bounds on the system outage probability. We prove that the system can achieve a diversity order (DO) equal to the number of relays. In addition, and importantly, we show that the considered correlation form has a constructive effect on the system performance. In other words, the larger the correlation coefficient, the better system performance. Our analytic results are corroborated by extensive Monte-Carlo simulations. PMID:27626426

  5. 47 CFR 64.606 - Internet-based TRS provider and TRS program certification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of Internet-based TRS to be provided (i.e., VRS, IP Relay, and/or IP captioned telephone relay... IP Relay providers certified under this section must notify the Commission of substantive changes in...

  6. Reputation-Based Trust for a Cooperative, Agent-Based Backup Protection Scheme for Power Networks

    DTIC Science & Technology

    2010-03-01

    85 Appendix B . Performance Charts for Data by Scenario...protection for that line. For example Relay 3 provides zone 1 coverage for line B and zone 3 coverage for line C. Relay 4 would also provide zone 1...coverage for line B but zone 3 coverage for line A instead since it is directional. Relay 1 and relay 6 would provide zone 3 coverage for line B . A

  7. Differential correction capability of the GTDS using TDRSS data

    NASA Technical Reports Server (NTRS)

    Liu, S. Y.; Soskey, D. G.; Jacintho, J.

    1980-01-01

    A differential correction (DC) capability was implemented in the Goddard Trajectory Determination System (GTDS) to process satellite tracking data acquired via the Tracking and Data Relay Satellite System (TRDRSS). Configuration of the TDRSS is reviewed, observation modeling is presented, and major features of the capability are discussed. The following types of TDRSS data can be processed by GTDS: two way relay range and Doppler measurements, hybrid relay range and Doppler measurements, one way relay Doppler measurements, and differenced one way relay Doppler measurements. These data may be combined with conventional ground based direct tracking data. By using Bayesian weighted least squares techniques, the software allows the simultaneous determination of the trajectories of up to four different satellites - one user satellite and three relay satellites. In addition to satellite trajectories, the following parameters can be optionally solved: for drag coefficient, reflectivity of a satellite for solar radiation pressure, transponder delay, station position, and biases.

  8. Integrating a New Medicinal Chemistry and Pharmacology Course Sequence into the PharmD Curriculum

    PubMed Central

    Engels, Melanie; Garcia, George

    2015-01-01

    Objective. To evaluate the implementation of an integrated medicinal chemistry/pharmacology course sequence and its alignment with a therapeutics series. Design. Each topic was divided into modules consisting of 2-hour blocks, and the content was integrated and aligned with the therapeutics series. Recitation sessions emphasizing application skills in an interactive environment followed each of three 2-hour blocks. To ensure that students achieved competency in each unit, students failing any unit examination were encouraged to undergo remediation. Assessment. Student feedback was collected by an independent researcher through social media and focus groups and relayed anonymously to course directors for midcourse improvements. Responses from surveys, interviews, and student ratings of faculty members and of courses were used to implement changes for future editions of the courses. Conclusion. The majority of students and faculty members felt the integration and alignment processes were beneficial changes to the curriculum. Elements of the new sequence, including remediation, were viewed positively by students and faculty members as well. PMID:25741029

  9. 32 CFR 321.13 - Exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... investigations and relay law enforcement information without compromise of the information, protection of... investigations and relay law enforcement information without compromise of the information, protection of... subsection (c)(3) because it will enable DSS to conduct certain investigations and relay law enforcement...

  10. Evolution of a radio communication relay system

    NASA Astrophysics Data System (ADS)

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

    2013-05-01

    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.

  11. The Relay/Converter Interface Influences Hydrolysis of ATP by Skeletal Muscle Myosin II*

    PubMed Central

    Bloemink, Marieke J.; Melkani, Girish C.; Bernstein, Sanford I.; Geeves, Michael A.

    2016-01-01

    The interface between relay and converter domain of muscle myosin is critical for optimal myosin performance. Using Drosophila melanogaster indirect flight muscle S1, we performed a kinetic analysis of the effect of mutations in the converter and relay domain. Introduction of a mutation (R759E) in the converter domain inhibits the steady-state ATPase of myosin S1, whereas an additional mutation in the relay domain (N509K) is able to restore the ATPase toward wild-type values. The R759E S1 construct showed little effect on most steps of the actomyosin ATPase cycle. The exception was a 25–30% reduction in the rate constant of the hydrolysis step, the step coupled to the cross-bridge recovery stroke that involves a change in conformation at the relay/converter domain interface. Significantly, the double mutant restored the hydrolysis step to values similar to the wild-type myosin. Modeling the relay/converter interface suggests a possible interaction between converter residue 759 and relay residue 509 in the actin-detached conformation, which is lost in R759E but is restored in N509K/R759E. This detailed kinetic analysis of Drosophila myosin carrying the R759E mutation shows that the interface between the relay loop and converter domain is important for fine-tuning myosin kinetics, in particular ATP binding and hydrolysis. PMID:26586917

  12. Analytical Approaches for Identification and Representation of Critical Protection Systems in Transient Stability Studies

    NASA Astrophysics Data System (ADS)

    Hedman, Mojdeh Khorsand

    After a major disturbance, the power system response is highly dependent on protection schemes and system dynamics. Improving power systems situational awareness requires proper and simultaneous modeling of both protection schemes and dynamic characteristics in power systems analysis tools. Historical information and ex-post analysis of blackouts reaffirm the critical role of protective devices in cascading events, thereby confirming the necessity to represent protective functions in transient stability studies. This dissertation is aimed at studying the importance of representing protective relays in power system dynamic studies. Although modeling all of the protective relays within transient stability studies may result in a better estimation of system behavior, representing, updating, and maintaining the protection system data becomes an insurmountable task. Inappropriate or outdated representation of the relays may result in incorrect assessment of the system behavior. This dissertation presents a systematic method to determine essential relays to be modeled in transient stability studies. The desired approach should identify protective relays that are critical for various operating conditions and contingencies. The results of the transient stability studies confirm that modeling only the identified critical protective relays is sufficient to capture system behavior for various operating conditions and precludes the need to model all of the protective relays. Moreover, this dissertation proposes a method that can be implemented to determine the appropriate location of out-of-step blocking relays. During unstable power swings, a generator or group of generators may accelerate or decelerate leading to voltage depression at the electrical center along with generator tripping. This voltage depression may cause protective relay mis-operation and unintentional separation of the system. In order to avoid unintentional islanding, the potentially mis-operating relays should be blocked from tripping with the use of out-of-step blocking schemes. Blocking these mis-operating relays, combined with an appropriate islanding scheme, help avoid a system wide collapse. The proposed method is tested on data from the Western Electricity Coordinating Council. A triple line outage of the California-Oregon Intertie is studied. The results show that the proposed method is able to successfully identify proper locations of out-of-step blocking scheme.

  13. Case Report of Relay Liver Transplantation With Graft Infected With Hepatitis B Virus.

    PubMed

    Wong, T C L; She, W H; Cheung, T T; Chan, S C; Lo, C M

    2015-11-01

    Reuse of liver graft for transplantation is extremely uncommon. We report the 1st case of reuse of liver graft from a recipient who had hepatitis B virus (HBV) infection, 11 years after the 1st transplantation. Our relay liver transplantation challenged conventional thinking because of late reuse of graft in the presence of HBV infection. Moreover, both the 1st and the 2nd donors were of advanced age. The key questions were whether the liver graft could be reused safely, especially in the setting of HBV infection, and technical concerns during organ procurement and implantation. The absence of HBV replication was confirmed with negative hepatitis B surface antigen and undetectable serum HBV DNA in the 2nd donor. Based on our experience in managing HBV infection after liver transplantation, we were confident that the adequately suppressed HBV infection in the donor would not jeopardize graft function and that the graft would be able to withstand another ischemia-perfusion injury to continue to function well in our recipient. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. 14 CFR 1215.102 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION TRACKING AND DATA RELAY SATELLITE SYSTEM.... The Tracking and Data Relay Satellite System including Tracking and Data Relay Satellites (TDRS), the... user ground system/TDRSS interface. (c) Bit stream. The digital electronic signals acquired by TDRSS...

  15. Design study of a HEAO-C spread spectrum transponder telemetry system for use with the TDRSS subnet

    NASA Technical Reports Server (NTRS)

    Weathers, G.

    1975-01-01

    The results of a design study of a spread spectrum transponder for use on the HEAO-C satellite were given. The transponder performs the functions of code turn-around for ground range and range-rate determination, ground command receiver, and telemetry data transmitter. The spacecraft transponder and associated communication system components will allow the HEAO-C satellite to utilize the Tracking and Data Relay Satellite System (TDRSS) subnet of the post 1978 STDN. The following areas were discussed in the report: TDRSS Subnet Description, TDRSS-HEAO-C System Configuration, Gold Code Generator, Convolutional Encoder Design and Decoder Algorithm, High Speed Sequence Generators, Statistical Evaluation of Candidate Code Sequences using Amplitude and Phase Moments, Code and Carrier Phase Lock Loops, Total Spread Spectrum Transponder System, and Reference Literature Search.

  16. Achievable rate maximization for decode-and-forward MIMO-OFDM networks with an energy harvesting relay.

    PubMed

    Du, Guanyao; Yu, Jianjun

    2016-01-01

    This paper investigates the system achievable rate for the multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system with an energy harvesting (EH) relay. Firstly we propose two protocols, time switching-based decode-and-forward relaying (TSDFR) and a flexible power splitting-based DF relaying (PSDFR) protocol by considering two practical receiver architectures, to enable the simultaneous information processing and energy harvesting at the relay. In PSDFR protocol, we introduce a temporal parameter to describe the time division pattern between the two phases which makes the protocol more flexible and general. In order to explore the system performance limit, we discuss the system achievable rate theoretically and formulate two optimization problems for the proposed protocols to maximize the system achievable rate. Since the problems are non-convex and difficult to solve, we first analyze them theoretically and get some explicit results, then design an augmented Lagrangian penalty function (ALPF) based algorithm for them. Numerical results are provided to validate the accuracy of our analytical results and the effectiveness of the proposed ALPF algorithm. It is shown that, PSDFR outperforms TSDFR to achieve higher achievable rate in such a MIMO-OFDM relaying system. Besides, we also investigate the impacts of the relay location, the number of antennas and the number of subcarriers on the system performance. Specifically, it is shown that, the relay position greatly affects the system performance of both protocols, and relatively worse achievable rate is achieved when the relay is placed in the middle of the source and the destination. This is different from the MIMO-OFDM DF relaying system without EH. Moreover, the optimal factor which indicates the time division pattern between the two phases in the PSDFR protocol is always above 0.8, which means that, the common division of the total transmission time into two equal phases in previous work applying PS-based receiver is not optimal.

  17. Airborne relay-based regional positioning system.

    PubMed

    Lee, Kyuman; Noh, Hongjun; Lim, Jaesung

    2015-05-28

    Ground-based pseudolite systems have some limitations, such as low vertical accuracy, multipath effects and near-far problems. These problems are not significant in airborne-based pseudolite systems. However, the monitoring of pseudolite positions is required because of the mobility of the platforms on which the pseudolites are mounted, and this causes performance degradation. To address these pseudolite system limitations, we propose an airborne relay-based regional positioning system that consists of a master station, reference stations, airborne relays and a user. In the proposed system, navigation signals are generated from the reference stations located on the ground and are relayed via the airborne relays. Unlike in conventional airborne-based systems, the user in the proposed system sequentially estimates both the locations of airborne relays and his/her own position. Therefore, a delay due to monitoring does not occur, and the accuracy is not affected by the movement of airborne relays. We conducted several simulations to evaluate the performance of the proposed system. Based on the simulation results, we demonstrated that the proposed system guarantees a higher accuracy than airborne-based pseudolite systems, and it is feasible despite the existence of clock offsets among reference stations.

  18. Airborne Relay-Based Regional Positioning System

    PubMed Central

    Lee, Kyuman; Noh, Hongjun; Lim, Jaesung

    2015-01-01

    Ground-based pseudolite systems have some limitations, such as low vertical accuracy, multipath effects and near-far problems. These problems are not significant in airborne-based pseudolite systems. However, the monitoring of pseudolite positions is required because of the mobility of the platforms on which the pseudolites are mounted, and this causes performance degradation. To address these pseudolite system limitations, we propose an airborne relay-based regional positioning system that consists of a master station, reference stations, airborne relays and a user. In the proposed system, navigation signals are generated from the reference stations located on the ground and are relayed via the airborne relays. Unlike in conventional airborne-based systems, the user in the proposed system sequentially estimates both the locations of airborne relays and his/her own position. Therefore, a delay due to monitoring does not occur, and the accuracy is not affected by the movement of airborne relays. We conducted several simulations to evaluate the performance of the proposed system. Based on the simulation results, we demonstrated that the proposed system guarantees a higher accuracy than airborne-based pseudolite systems, and it is feasible despite the existence of clock offsets among reference stations. PMID:26029953

  19. Exploiting Outage and Error Probability of Cooperative Incremental Relaying in Underwater Wireless Sensor Networks

    PubMed Central

    Nasir, Hina; Javaid, Nadeem; Sher, Muhammad; Qasim, Umar; Khan, Zahoor Ali; Alrajeh, Nabil; Niaz, Iftikhar Azim

    2016-01-01

    This paper embeds a bi-fold contribution for Underwater Wireless Sensor Networks (UWSNs); performance analysis of incremental relaying in terms of outage and error probability, and based on the analysis proposition of two new cooperative routing protocols. Subject to the first contribution, a three step procedure is carried out; a system model is presented, the number of available relays are determined, and based on cooperative incremental retransmission methodology, closed-form expressions for outage and error probability are derived. Subject to the second contribution, Adaptive Cooperation in Energy (ACE) efficient depth based routing and Enhanced-ACE (E-ACE) are presented. In the proposed model, feedback mechanism indicates success or failure of data transmission. If direct transmission is successful, there is no need for relaying by cooperative relay nodes. In case of failure, all the available relays retransmit the data one by one till the desired signal quality is achieved at destination. Simulation results show that the ACE and E-ACE significantly improves network performance, i.e., throughput, when compared with other incremental relaying protocols like Cooperative Automatic Repeat reQuest (CARQ). E-ACE and ACE achieve 69% and 63% more throughput respectively as compared to CARQ in hard underwater environment. PMID:27420061

  20. Relay Support for the Mars Science Laboratory and the Coming Decade of Mars Relay Network Evolution

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D., Jr.; Arnold, Bradford W.; Bell, David J.; Bruvold, Kristoffer N.; Gladden, Roy E.; Ilott, Peter A.; Lee, Charles H.

    2012-01-01

    In the past decade, an evolving network of Mars relay orbiters has provided telecommunication relay services to the Mars Exploration Rovers, Spirit and Opportunity, and to the Mars Phoenix Lander, enabling high-bandwidth, energy-efficient data transfer and greatly increasing the volume of science data that can be returned from the Martian surface, compared to conventional direct-to-Earth links. The current relay network, consisting of NASA's Odyssey and Mars Reconnaissance Orbiter and augmented by ESA's Mars Express Orbiter, stands ready to support the Mars Science Laboratory, scheduled to arrive at Mars on Aug 6, 2012, with new capabilities enabled by the Electra and Electra-Lite transceivers carried by MRO and MSL, respectively. The MAVEN orbiter, planned for launch in 2013, and the ExoMars/Trace Gas Orbiter, planned for launch in 2016, will replenish the on-orbit relay network as the current orbiter approach their end of life. Currently planned support scenarios for this future relay network include an ESA EDL Demonstrator Module deployed by the 2016 ExoMars/TGO orbiter, and the 2018 NASA/ESA Joint Rover, representing the first step in a multimission Mars Sample Return campaign.

  1. Rack protection monitor

    DOEpatents

    Orr, Stanley G.

    2000-01-01

    A hardwired, fail-safe rack protection monitor utilizes electromechanical relays to respond to the detection by condition sensors of abnormal or alarm conditions (such as smoke, temperature, wind or water) that might adversely affect or damage equipment being protected. When the monitor is reset, the monitor is in a detection mode with first and second alarm relay coils energized. If one of the condition sensors detects an abnormal condition, the first alarm relay coil will be de-energized, but the second alarm relay coil will remain energized. This results in both a visual and an audible alarm being activated. If a second alarm condition is detected by another one of the condition sensors while the first condition sensor is still detecting the first alarm condition, both the first alarm relay coil and the second alarm relay coil will be de-energized. With both the first and second alarm relay coils de-energized, both a visual and an audible alarm will be activated. In addition, power to the protected equipment will be terminated and an alarm signal will be transmitted to an alarm central control. The monitor can be housed in a separate enclosure so as to provide an interface between a power supply for the protected equipment and the protected equipment.

  2. Relay cropping as a sustainable approach: problems and opportunities for sustainable crop production.

    PubMed

    Tanveer, Mohsin; Anjum, Shakeel Ahmad; Hussain, Saddam; Cerdà, Artemi; Ashraf, Umair

    2017-03-01

    Climate change, soil degradation, and depletion of natural resources are becoming the most prominent challenges for crop productivity and environmental sustainability in modern agriculture. In the scenario of conventional farming system, limited chances are available to cope with these issues. Relay cropping is a method of multiple cropping where one crop is seeded into standing second crop well before harvesting of second crop. Relay cropping may solve a number of conflicts such as inefficient use of available resources, controversies in sowing time, fertilizer application, and soil degradation. Relay cropping is a complex suite of different resource-efficient technologies, which possesses the capability to improve soil quality, to increase net return, to increase land equivalent ratio, and to control the weeds and pest infestation. The current review emphasized relay cropping as a tool for crop diversification and environmental sustainability with special focus on soil. Briefly, benefits, constraints, and opportunities of relay cropping keeping the goals of higher crop productivity and sustainability have also been discussed in this review. The research and knowledge gap in relay cropping was also highlighted in order to guide the further studies in future.

  3. Tracking and data relay satellite system configuration and tradeoff study, part 1. Volume 3: Telecommunications service system

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The results of the telecommunications subsystem analysis are presented. The relay system requirements and constraints, interference analysis, frequency selection, modulation and coding analysis, and the performance analysis of the relay system are included.

  4. 76 FR 72124 - Internet-Based Telecommunications Relay Service Numbering

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... Docket No. 10-191; FCC 11-123] Internet-Based Telecommunications Relay Service Numbering AGENCY: Federal..., the information collection associated with the Commission's Internet- Based Telecommunications Relay... this notice as an announcement of the effective date of the rules. See Internet-Based...

  5. 77 FR 1039 - Internet-Based Telecommunications Relay Service Numbering

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-09

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [WC Docket No. 10-191; Report No. 2939] Internet... toll-free numbers by users of Internet- based Telecommunications Relay Services (iTRS). DATES... any rules of particular applicability. Subject: Internet-Based Telecommunications Relay Service...

  6. 47 CFR 64.603 - Provision of services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... telephone voice transmission services shall provide, not later than July 26, 1993, in compliance with the regulations prescribed herein, throughout the area in which it offers services, telecommunications relay... other carriers. Speech-to-speech relay service and interstate Spanish language relay service shall be...

  7. A TorPath to TorCoin: Proof-of-Bandwidth Altcoins for Compensating Relays

    DTIC Science & Technology

    2014-07-18

    incentive scheme for Tor relying on two novel concepts. We introduce TorCoin, an “altcoin” that uses the Bitcoin protocol to re- ward relays for...or altcoin, based on the Bitcoin protocol [8]. Unlike Bitcoin , its proof-of-work scheme is based on bandwidth rather than computation. To “mine” a...concepts. We introduce TorCoin, an altcoin" that uses the Bitcoin protocol to re- ward relays for contributing bandwidth. Relays mine" TorCoins, then

  8. Benefits of smart pumps for automated changeovers of vasoactive drug infusion pumps: a quasi-experimental study.

    PubMed

    Cour, M; Hernu, R; Bénet, T; Robert, J M; Regad, D; Chabert, B; Malatray, A; Conrozier, S; Serra, P; Lassaigne, M; Vanhems, P; Argaud, L

    2013-11-01

    Manual changeover of vasoactive drug infusion pumps (CVIP) frequently lead to haemodynamic instability. Some of the newest smart pumps allow automated CVIP. The aim of this study was to compare automated CVIP with manual 'Quick Change' relays. We performed a prospective, quasi-experimental study, in a university-affiliated intensive care unit (ICU). All adult patients receiving continuous i.v. infusion of vasoactive drugs were included. CVIP were successively performed manually (Phase 1) and automatically (Phase 2) during two 6-month periods. The primary endpoint was the frequency of haemodynamic incidents related to the relays, which were defined as variations of mean arterial pressure >15 mm Hg or heart rate >15 bpm. The secondary endpoints were the nursing time dedicated to relays and the number of interruptions in care because of CVIP. A multivariate mixed effects logistic regression was fitted for analytic analysis. We studied 1329 relays (Phase 1: 681, Phase 2: 648) from 133 patients (Phase 1: 63, Phase 2: 70). Incidents related to CVIP decreased from 137 (20%) in Phase 1 to 73 (11%) in Phase 2 (P<0.001). Automated relays were independently associated with a 49% risk reduction of CVIP-induced incidents (adjusted OR=0.51, 95% confidence interval 0.34-0.77, P=0.001). Time dedicated to the relays and the number of interruptions in care to manage CVIP were also significantly reduced with automated relays vs manual relays (P=0.001). These results demonstrate the benefits of automated CVIP using smart pumps in limiting the frequency of haemodynamic incidents related to relays and in reducing the nursing workload.

  9. Section 7 reactor incident file general information from 1945

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1969-01-10

    At 0308 on January 10, 1966, both B and C Reactors ``scrammed`` due to an electrical fault on Line C2-L8 caused by a raccoon coming in contact with the 13-8 KV line on top of transformer No. 2 at 182-B Building. Line C2-L8 relayed out at the 151-B Building. Details of the occurrence at 151-B are covered in the attachment. C-Reactor scrammed due to reduced voltage on the pressure monitor system. The reduction in voltage caused the auxiliary relays of the pressure monitor ground detector to open, de-energizing the end result relays PSR and PSRA. The safety circuit trip identificationmore » system displayed ``Pressure Monitor`` and ``Ground Detector.`` B-Reactor scrammed by a power failure signal from 190-B Building. The power failure relays for pump numbers 1 and 3 opened due to these pumps contributing power to the fault. The power failure relays at 190-B remained open long enough for the end result relays PF and PFA to open. Since these relays are timed delayed, 0.26 seconds, the power failure relays must have remained open at least that long. At the 190-B Building the steam turbines started due to the power failure relays for pump numbers 1 and 3 opening. The main process pumps remained stable and continued to supply normal flow to the reactor. Pumps were tripped from the line at 182-B and 183-B Buildings. The surge suppressors cycled normally and the turbine export pumps started as a result of low export line pressure. No power equipment was affected in C Area.« less

  10. Modeling of Protection in Dynamic Simulation Using Generic Relay Models and Settings

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Samaan, Nader A.; Dagle, Jeffery E.; Makarov, Yuri V.

    This paper shows how generic protection relay models available in planning tools can be augmented with settings that are based on NERC standards or best engineering practice. Selected generic relay models in Siemens PSS®E have been used in dynamic simulations in the proposed approach. Undervoltage, overvoltage, underfrequency, and overfrequency relays have been modeled for each generating unit. Distance-relay protection was modeled for transmission system protection. Two types of load-shedding schemes were modeled: underfrequency (frequency-responsive non-firm load shedding) and underfrequency and undervoltage firm load shedding. Several case studies are given to show the impact of protection devices on dynamic simulations. Thismore » is useful for simulating cascading outages.« less

  11. Modeling study of the ABS relay valve

    NASA Astrophysics Data System (ADS)

    Lei, Ming; Lin, Min; Guo, Bin; Luo, Zai; Xu, Weidong

    2011-05-01

    The ABS (anti-lock braking system) relay valve is the key component of anti-lock braking system in most commercial vehicles such as trucks, tractor-trailers, etc. In this paper, structure of ABS relay valve and its work theory were analyzed. Then a mathematical model of ABS relay valve, which was investigated by dividing into electronic part, magnetic part, pneumatic part and mechanical part, was set up. The displacement of spools and the response of pressure increasing, holding, releasing of ABS relay valve were simulated and analyzed under conditions of control pressure 500 KPa, braking pressure 600 KPa, atmospheric pressure 100 KPa and air temperature 310 K. Thisarticle provides reliable theory for improving the performance and efficiency of anti-lock braking system of vehicles.

  12. Outage Analysis of Dual-hop Cognitive Networks with Relay Selection over Nakagami-m Fading Environment

    NASA Astrophysics Data System (ADS)

    Zhang, Zongsheng; Pi, Xurong

    2014-09-01

    In this paper, we investigate the outage performance of decode-and-forward cognitive relay networks for Nakagami-m fading channels, with considering both best relay selection and interference constraints. Focusing on the relay selection and making use of the underlay cognitive approach, an exact closed-form outage probability expression is derived in an independent, non-identical distributed Nakagami-m environment. The closed-form outage probability provides an efficient means to evaluate the effects of the maximum allowable interference power, number of cognitive relays, and channel conditions between the primary user and cognitive users. Finally, we present numerical results to validate the theory analysis. Moreover, from the simulation results, we obtain that the system can obtain the full diversity.

  13. Quantum cryptography with an ideal local relay

    NASA Astrophysics Data System (ADS)

    Spedalieri, Gaetana; Ottaviani, Carlo; Braunstein, Samuel L.; Gehring, Tobias; Jacobsen, Christian S.; Andersen, Ulrik L.; Pirandola, Stefano

    2015-10-01

    We consider two remote parties connected to a relay by two quantum channels. To generate a secret key, they transmit coherent states to the relay, where the states are subject to a continuous-variable (CV) Bell detection. We study the ideal case where Alice's channel is lossless, i.e., the relay is locally in her lab and the Bell detection is perfomed with unit efficiency. This configuration allows us to explore the optimal performances achievable by CV measurement-device-independent quantum key distribution. This corresponds to the limit of a trusted local relay, where the detection loss can be re-scaled. Our theoretical analysis is confirmed by an experimental simulation where 10-4 secret bits per use can potentially be distributed at 170km assuming ideal reconciliation.

  14. Improved BDF Relaying Scheme Using Time Diversity over Atmospheric Turbulence and Misalignment Fading Channels

    PubMed Central

    García-Zambrana, Antonio; Castillo-Vázquez, Carmen; Castillo-Vázquez, Beatriz

    2014-01-01

    A novel bit-detect-and-forward (BDF) relaying scheme based on repetition coding with the relay is proposed, significantly improving the robustness to impairments proper to free-space optical (FSO) communications such as unsuitable alignment between transmitter and receiver as well as fluctuations in the irradiance of the transmitted optical beam due to the atmospheric turbulence. Closed-form asymptotic bit-error-rate (BER) expressions are derived for a 3-way FSO communication setup. Fully exploiting the potential time-diversity available in the relay turbulent channel, a relevant better performance is achieved, showing a greater robustness to the relay location since a high diversity gain is provided regardless of the source-destination link distance. PMID:24587711

  15. Signal relay during the life cycle of Dictyostelium.

    PubMed

    Mahadeo, Dana C; Parent, Carole A

    2006-01-01

    A fundamental property of multicellular organisms is signal relay, the process by which information is transmitted from one cell to another. The integration of external information, such as nutritional status or developmental cues, is critical to the function of organisms. In addition, the spatial organizations of multicellular organisms require intricate signal relay mechanisms. Signal relay is remarkably exhibited during the life cycle of the social amoebae Dictyostelium discoideum, a eukaryote that retains a simple way of life, yet it has greatly contributed to our knowledge of the mechanisms cells use to communicate and integrate information. This chapter focuses on the molecules and mechanisms that Dictyostelium employs during its life cycle to relay temporal and spatial cues that are required for survival.

  16. 47 CFR 11.20 - State Relay Network.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false State Relay Network. 11.20 Section 11.20... Network. This network is composed of State Relay (SR) sources, leased common carrier communications facilities or any other available communication facilities. The network distributes State EAS messages...

  17. 47 CFR 11.20 - State Relay Network.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false State Relay Network. 11.20 Section 11.20... Network. This network is composed of State Relay (SR) sources, leased common carrier communications facilities or any other available communication facilities. The network distributes State EAS messages...

  18. That Article: Frame Relay.

    ERIC Educational Resources Information Center

    Schuyler, Michael

    1994-01-01

    Compares Frame Relay with digital and analog alternatives for connecting sites on a Wide Area Network. Cost considerations, the concepts on which the technology is based, its carrying capacity, the use of CD-ROM and Graphical User Interface (GUI) on Frame Relay, and engineering bandwidth limitations are covered. (KRN)

  19. 76 FR 67118 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-31

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Proposed... Commission's Structure and Practices of the Video Relay Service Program, Further Notice of Proposed..., and video using wired telecommunications networks. Transmission facilities may be based on a single...

  20. Quantum network with trusted and untrusted relays

    NASA Astrophysics Data System (ADS)

    Ma, Xiongfeng; Annabestani, Razieh; Fung, Chi-Hang Fred; Lo, Hoi-Kwong; Lütkenhaus, Norbert; PitkäNen, David; Razavi, Mohsen

    2012-02-01

    Quantum key distribution offers two distant users to establish a random secure key by exploiting properties of quantum mechanics, whose security has proven in theory. In practice, many lab and field demonstrations have been performed in the last 20 years. Nowadays, quantum network with quantum key distribution systems are tested around the world, such as in China, Europe, Japan and US. In this talk, I will give a brief introduction of recent development for quantum network. For the untrusted relay part, I will introduce the measurement-device-independent quantum key distribution scheme and a quantum relay with linear optics. The security of such scheme is proven without assumptions on the detection devices, where most of quantum hacking strategies are launched. This scheme can be realized with current technology. For the trusted relay part, I will introduce so-called delayed privacy amplification, with which no error correction and privacy amplification is necessarily to be performed between users and the relay. In this way, classical communications and computational power requirement on the relay site will be reduced.

  1. Proximity Link Design and Performance Options for a Mars Areostationary Relay Satellite

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D.; Bell, David J.; Biswas, Abhijit; Cheung, Kar-Ming; Lock, Robert E.

    2016-01-01

    Current and near-term Mars relay telecommunications services are provided by a set of NASA and ESA Mars science orbiters equipped with UHF relay communication payloads employing operationally simple low-gain antennas. These have been extremely successful in supporting a series of landed Mars mission, greatly increasing data return relative to direct-to-Earth lander links. Yet their relay services are fundamentally constrained by the short contact times available from the selected science orbits. Future Mars areostationary orbiters, flying in circular, equatorial, 1- sol orbits, offer the potential for continuous coverage of Mars landers and rovers, radically changing the relay support paradigm. Achieving high rates on the longer slant ranges to areostationary altitude will require steered, high-gain links. Both RF and optical options exist for achieving data rates in excess of 100 Mb/s. Several point designs offer a measure of potential user burden, in terms of mass, volume, power, and pointing requirements for user relay payloads, as a function of desired proximity link performance.

  2. Modeling Zone-3 Protection with Generic Relay Models for Dynamic Contingency Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Qiuhua; Vyakaranam, Bharat GNVSR; Diao, Ruisheng

    This paper presents a cohesive approach for calculating and coordinating the settings of multiple zone-3 protections for dynamic contingency analysis. The zone-3 protections are represented by generic distance relay models. A two-step approach for determining zone-3 relay settings is proposed. The first step is to calculate settings, particularly, the reach, of each zone-3 relay individually by iteratively running line open-end fault short circuit analysis; the blinder is also employed and properly set to meet the industry standard under extreme loading conditions. The second step is to systematically coordinate the protection settings of the zone-3 relays. The main objective of thismore » coordination step is to address the over-reaching issues. We have developed a tool to automate the proposed approach and generate the settings of all distance relays in a PSS/E dyr format file. The calculated zone-3 settings have been tested on a modified IEEE 300 system using a dynamic contingency analysis tool (DCAT).« less

  3. Performance of an optical relay satellite using Reed-Solomon coding over a cascaded optical PPM and BPSK channel

    NASA Technical Reports Server (NTRS)

    Divsalar, D.; Naderi, F.

    1982-01-01

    The nature of the optical/microwave interface aboard the relay satellite is considered. To allow for the maximum system flexibility, without overburdening either the optical or RF channel, demodulating the optical on board the relay satellite but leaving the optical channel decoding to be performed at the ground station is examined. The occurrence of erasures in the optical channel is treated. A hard decision on the erasure (i.e., the relay selecting a symbol at random in case of erasure occurrence) seriously degrades the performance of the overall system. Coding the erasure occurrences at the relay and transmitting this information via an extra bit to the ground station where it can be used by the decoder is suggested. Many examples with varying bit/photon energy efficiency and for the noisy and noiseless optical channel are considered. It is shown that coding the erasure occurrences dramatically improves the performance of the cascaded channel relative to the case of hard decision on the erasure by the relay.

  4. Wireless Relay Selection in Pocket Switched Networks Based on Spatial Regularity of Human Mobility †

    PubMed Central

    Huang, Jianhui; Cheng, Xiuzhen; Bi, Jingping; Chen, Biao

    2016-01-01

    Pocket switched networks (PSNs) take advantage of human mobility to deliver data. Investigations on real-world trace data indicate that human mobility shows an obvious spatial regularity: a human being usually visits a few places at high frequencies. These most frequently visited places form the home of a node, which is exploited in this paper to design two HomE based Relay selectiOn (HERO) algorithms. Both algorithms input single data copy into the network at any time. In the basic HERO, only the first node encountered by the source and whose home overlaps a destination’s home is selected as a relay while the enhanced HERO keeps finding more optimal relay that visits the destination’s home with higher probability. The two proposed algorithms only require the relays to exchange the information of their home and/or the visiting frequencies to their home when two nodes meet. As a result, the information update is reduced and there is no global status information that needs to be maintained. This causes light loads on relays because of the low communication cost and storage requirements. Additionally, only simple operations are needed in the two proposed algorithms, resulting in little computation overhead at relays. At last, a theoretical analysis is performed on some key metrics and then the real-world based simulations indicate that the two HERO algorithms are efficient and effective through employing only one or a few relays. PMID:26797609

  5. Interactions between relay helix and Src homology 1 domain helix (SH1) drive the converter domain rotation during the recovery stroke of myosin II

    PubMed Central

    Baumketner, Andrij

    2012-01-01

    Myosin motor protein exists in two alternative conformations, pre-recovery state M* and post-recovery state M**, upon ATP binding. The details of the M*-to-M** transition, known as the recovery stroke to reflect its role as the functional opposite of the force-generating power stroke, remain elusive. The defining feature of the post-recovery state is a kink in the relay helix, a key part of the protein involved in force generation. In this paper we determine the interactions that are responsible for the appearance of the kink. We design a series of computational models that contain three other segments, relay loop, converter domain and Src homology 1 domain helix (SH1), with which relay helix interacts, and determine their structure in accurate replica exchange molecular dynamics simulations in explicit solvent. By conducting an exhaustive combinatorial search among different models we find that: 1) the converter domain must be attached to the relay helix during the transition, so it does not interfere with other parts of the protein, 2) the structure of the relay helix is controlled by SH1 helix. The kink is strongly coupled to the position of SH1 helix. It arises as a result of direct interactions between SH1 and the relay helix and leads to a rotation of the C-terminal part of the relay helix which is subsequently transmitted to the converter domain. PMID:22411190

  6. Relay Support for the Mars Science Laboratory Mission

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D. Jr,; Bell, David J.; Gladden, Roy E.; Ilott, Peter A.; Jedrey, Thomas C.; Johnston, M. Daniel; Maxwell, Jennifer L.; Mendoza, Ricardo; McSmith, Gaylon W.; Potts, Christopher L.; hide

    2013-01-01

    The Mars Science Laboratory (MSL) mission landed the Curiosity Rover on the surface of Mars on August 6, 2012, beginning a one-Martian-year primary science mission. An international network of Mars relay orbiters, including NASA's 2001 Mars Odyssey Orbiter (ODY) and Mars Reconnaissance Orbiter (MRO), and ESA's Mars Express Orbiter (MEX), were positioned to provide critical event coverage of MSL's Entry, Descent, and Landing (EDL). The EDL communication plan took advantage of unique and complementary capabilities of each orbiter to provide robust information capture during this critical event while also providing low-latency information during the landing. Once on the surface, ODY and MRO have provided effectively all of Curiosity's data return from the Martian surface. The link from Curiosity to MRO incorporates a number of new features enabled by the Electra and Electra-Lite software-defined radios on MRO and Curiosity, respectively. Specifically, the Curiosity-MRO link has for the first time on Mars relay links utilized frequency-agile operations, data rates up to 2.048 Mb/s, suppressed carrier modulation, and a new Adaptive Data Rate algorithm in which the return link data rate is optimally varied throughout the relay pass based on the actual observed link channel characteristics. In addition to the baseline surface relay support by ODY and MRO, the MEX relay service has been verified in several successful surface relay passes, and MEX now stands ready to provide backup relay support should NASA's orbiters become unavailable for some period of time.

  7. The Relay/Converter Interface Influences Hydrolysis of ATP by Skeletal Muscle Myosin II.

    PubMed

    Bloemink, Marieke J; Melkani, Girish C; Bernstein, Sanford I; Geeves, Michael A

    2016-01-22

    The interface between relay and converter domain of muscle myosin is critical for optimal myosin performance. Using Drosophila melanogaster indirect flight muscle S1, we performed a kinetic analysis of the effect of mutations in the converter and relay domain. Introduction of a mutation (R759E) in the converter domain inhibits the steady-state ATPase of myosin S1, whereas an additional mutation in the relay domain (N509K) is able to restore the ATPase toward wild-type values. The R759E S1 construct showed little effect on most steps of the actomyosin ATPase cycle. The exception was a 25-30% reduction in the rate constant of the hydrolysis step, the step coupled to the cross-bridge recovery stroke that involves a change in conformation at the relay/converter domain interface. Significantly, the double mutant restored the hydrolysis step to values similar to the wild-type myosin. Modeling the relay/converter interface suggests a possible interaction between converter residue 759 and relay residue 509 in the actin-detached conformation, which is lost in R759E but is restored in N509K/R759E. This detailed kinetic analysis of Drosophila myosin carrying the R759E mutation shows that the interface between the relay loop and converter domain is important for fine-tuning myosin kinetics, in particular ATP binding and hydrolysis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  8. 47 CFR 64.6040 - Rates for Telecommunications Relay Service (TRS) calling.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 3 2014-10-01 2014-10-01 false Rates for Telecommunications Relay Service (TRS) calling. 64.6040 Section 64.6040 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON....6040 Rates for Telecommunications Relay Service (TRS) calling. No Provider shall levy or collect any...

  9. 76 FR 59557 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ...] Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION... Structure and Practices of the Video Relay Service Program, Second Report and Order and Order in CG Docket... replies. In light of impending deadlines for initial and [[Page 59558

  10. 47 CFR Alphabetical Index - Part 74

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., Directional (Aural STL/Relays) 74.536 Antenna location— LPTV/TV Translator 74.737 FM Translators/Boosters 74... Automatic relay stations (Remote pickup) 74.436 Avoidance of interference (TV Auxiliaries) 74.604 BP='02... (Aural STL/Relays) 74.536 E Emergency information Broadcasting (All Services) 74.21 Emission authorized...

  11. 49 CFR 236.737 - Cut-section, relayed.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Cut-section, relayed. 236.737 Section 236.737..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.737 Cut-section, relayed. A cut-section where the energy for one track circuit is supplied through front contacts...

  12. 78 FR 54201 - Misuse of Internet Protocol (IP) Captioned Telephone Service; Telecommunications Relay Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-03

    ...] Misuse of Internet Protocol (IP) Captioned Telephone Service; Telecommunications Relay Services and... further possible actions necessary to improve internet protocol captioned telephone relay service (IP CTS... for calculating the compensation rate paid to IP CTS providers. This action is necessary to ensure...

  13. 77 FR 16486 - Airworthiness Directives; Fokker Services B.V. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-21

    ... values of nuts on circuit breakers, contactors and terminal blocks of the EPC and battery relay panel... battery relay panel]. The required actions include doing a general visual inspection to determine if... and circuit breakers, contactors, and terminal blocks of the EPC and battery relay panel, as...

  14. 49 CFR 236.737 - Cut-section, relayed.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Cut-section, relayed. 236.737 Section 236.737..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.737 Cut-section, relayed. A cut-section where the energy for one track circuit is supplied through front contacts...

  15. 47 CFR 90.243 - Mobile relay stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Service. (b) Special provisions for mobile relay operations: (1) In the Public Safety Pool, systems... authorized to operate on any frequency available for assignment to base stations. (5) A mobile station associated with mobile relay station(s) may not be authorized to operate on a frequency below 25 MHz. (c...

  16. Potential Means of Cost Reduction in Grade Crossing Motorist-Warning Control Equipment : Volume 2. Comparison of Solid State and Relay Devices and Techniques

    DOT National Transportation Integrated Search

    1977-12-01

    Consideration is given to the properties of solid-state circuits, miniature relays and large gravity-operated relays when applied to control systems for grade crossings equipped with train-activated motorist warnings. Factors discussed include origin...

  17. 76 FR 67070 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-31

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Final rule.... SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Structure and Practices of the Video Relay... supervision should be deemed to be employees of the provider, in satisfaction of the requirement that video...

  18. 75 FR 39945 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-13

    ... FEDERAL COMMUNICATIONS COMMISSION [CG Docket No. 10-51; FCC 10-88] Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Notice. SUMMARY: In this... Practices of the Video Relay Service Program, Declaratory Ruling, document FCC 10-88, adopted May 24, 2010...

  19. 75 FR 39859 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-13

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [CG Docket No. 10-51; FCC 10-88] Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Interim rule... a summary of the Commission's Structure and Practices of the Video Relay Service Program, Order...

  20. 76 FR 47476 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-05

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [CG Docket No. 10-51; FCC 11-118] Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Interim rule... summary of the Commission's Structure and Practices of the Video Relay Service Program, Order (Order...

  1. 77 FR 60630 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-04

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [CG Docket No. 10-51; FCC 11-54] Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Correcting... address fraud, waste, and abuse in the Video Relay Service (VRS) industry. DATES: Effective October 4...

  2. 77 FR 11997 - Consumer and Governmental Affairs Bureau Seeks To Refresh the Record Regarding Misuse of Internet...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... legitimate relay calls, however, are not entitled to these transparency and confidentiality protections... Relay Service AGENCY: Federal Communications Commission. ACTION: Proposed rule. SUMMARY: In this... refresh the record regarding misuse of Internet Protocol relay service. Further comments are requested to...

  3. 77 FR 20505 - Airworthiness Directives; The Boeing Company Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-05

    ... Company Model 757 airplanes. This AD requires replacing the power control relays for the fuel boost pumps and override pumps with new relays having a ground fault interrupter (GFI) feature. This AD also requires an electrical bonding resistance measurement for certain GFI relays to verify that certain bonding...

  4. 78 FR 73859 - Information Collections Being Reviewed by the Federal Communications Commission Under Delegated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-09

    ...: Telecommunications Relay Services and Speech-to-Speech Services for Individuals with Hearing and Speech Disabilities... enable the Commission to collect waiver reports from Telecommunications Relay Service (TRS) providers... Report and Order and Order on Reconsideration in Telecommunications Relay Services and Speech-to- Speech...

  5. Radio Relays Improve Wireless Products

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Signal Hill, California-based XCOM Wireless Inc. developed radio frequency micromachine (RF MEMS) relays with a Phase II Small Business Innovation Research (SBIR) contract through NASA?s Jet Propulsion Laboratory. In order to improve satellite communication systems, XCOM produced wireless RF MEMS relays and tunable capacitors that use metal-to-metal contact and have the potential to outperform most semiconductor technologies while using less power. These relays are used in high-frequency test equipment and instrumentation, where increased speed can mean significant cost savings. Applications now also include mainstream wireless applications and greatly improved tactical radios.

  6. Finite-SNR analysis for partial relaying cooperation with channel coding and opportunistic relay selection

    NASA Astrophysics Data System (ADS)

    Vu, Thang X.; Duhamel, Pierre; Chatzinotas, Symeon; Ottersten, Bjorn

    2017-12-01

    This work studies the performance of a cooperative network which consists of two channel-coded sources, multiple relays, and one destination. To achieve high spectral efficiency, we assume that a single time slot is dedicated to relaying. Conventional network-coded-based cooperation (NCC) selects the best relay which uses network coding to serve the two sources simultaneously. The bit error rate (BER) performance of NCC with channel coding, however, is still unknown. In this paper, we firstly study the BER of NCC via a closed-form expression and analytically show that NCC only achieves diversity of order two regardless of the number of available relays and the channel code. Secondly, we propose a novel partial relaying-based cooperation (PARC) scheme to improve the system diversity in the finite signal-to-noise ratio (SNR) regime. In particular, closed-form expressions for the system BER and diversity order of PARC are derived as a function of the operating SNR value and the minimum distance of the channel code. We analytically show that the proposed PARC achieves full (instantaneous) diversity order in the finite SNR regime, given that an appropriate channel code is used. Finally, numerical results verify our analysis and demonstrate a large SNR gain of PARC over NCC in the SNR region of interest.

  7. Development and Testing of a Two-UAV Communication Relay System.

    PubMed

    Li, Boyang; Jiang, Yifan; Sun, Jingxuan; Cai, Lingfeng; Wen, Chih-Yung

    2016-10-13

    In the development of beyond-line-of-sight (BLOS) Unmanned Aerial Vehicle (UAV) systems, communication between the UAVs and the ground control station (GCS) is of critical importance. The commonly used economical wireless modules are restricted by the short communication range and are easily blocked by obstacles. The use of a communication relay system provides a practical way to solve these problems, improving the performance of UAV communication in BLOS and cross-obstacle operations. In this study, a communication relay system, in which a quadrotor was used to relay radio communication for another quadrotor was developed and tested. First, the UAVs used as the airborne platform were constructed, and the hardware for the communication relay system was selected and built up. Second, a set of software programs and protocol for autonomous mission control, communication relay control, and ground control were developed. Finally, the system was fully integrated into the airborne platform and tested both indoor and in-flight. The Received Signal Strength Indication (RSSI) and noise value in two typical application scenarios were recorded. The test results demonstrated the ability of this system to extend the communication range and build communication over obstacles. This system also shows the feasibility to coordinate multiple UAVs' communication with the same relay structure.

  8. Development and Testing of a Two-UAV Communication Relay System

    PubMed Central

    Li, Boyang; Jiang, Yifan; Sun, Jingxuan; Cai, Lingfeng; Wen, Chih-Yung

    2016-01-01

    In the development of beyond-line-of-sight (BLOS) Unmanned Aerial Vehicle (UAV) systems, communication between the UAVs and the ground control station (GCS) is of critical importance. The commonly used economical wireless modules are restricted by the short communication range and are easily blocked by obstacles. The use of a communication relay system provides a practical way to solve these problems, improving the performance of UAV communication in BLOS and cross-obstacle operations. In this study, a communication relay system, in which a quadrotor was used to relay radio communication for another quadrotor was developed and tested. First, the UAVs used as the airborne platform were constructed, and the hardware for the communication relay system was selected and built up. Second, a set of software programs and protocol for autonomous mission control, communication relay control, and ground control were developed. Finally, the system was fully integrated into the airborne platform and tested both indoor and in-flight. The Received Signal Strength Indication (RSSI) and noise value in two typical application scenarios were recorded. The test results demonstrated the ability of this system to extend the communication range and build communication over obstacles. This system also shows the feasibility to coordinate multiple UAVs’ communication with the same relay structure. PMID:27754369

  9. Application of Phasor Measurement Units for Protection of Distribution Networks with High Penetration of Photovoltaic Sources

    NASA Astrophysics Data System (ADS)

    Meskin, Matin

    The rate of the integration of distributed generation (DG) units to the distribution level to meet the growth in demand increases as a reasonable replacement for costly network expansion. This integration brings many advantages to the consumers and power grids, as well as giving rise to more challenges in relation to protection and control. Recent research has brought to light the negative effects of DG units on short circuit currents and overcurrent (OC) protection systems in distribution networks. Change in the direction of fault current flow, increment or decrement of fault current magnitude, blindness of protection, feeder sympathy trip, nuisance trip of interrupting devices, and the disruption of coordination between protective devices are some potential impacts of DG unit integration. Among other types of DG units, the integration of renewable energy resources into the electric grid has seen a vast improvement in recent years. In particular, the interconnection of photovoltaic (PV) sources to the medium voltage (MV) distribution networks has experienced a rapid increase in the last decade. In this work, the effect of PV source on conventional OC relays in MV distribution networks is shown. It is indicated that the PV output fluctuation, due to changes in solar radiation, causes the magnitude and direction of the current to change haphazardly. These variations may result in the poor operation of OC relays as the main protective devices in the MV distribution networks. In other words, due to the bi-directional power flow characteristic and the fluctuation of current magnitude occurring in the presence of PV sources, a specific setting of OC relays is difficult to realize. Therefore, OC relays may operate in normal conditions. To improve the OC relay operation, a voltage-dependent-overcurrent protection is proposed. Although, this new method prevents the OC relay from maloperation, its ability to detect earth faults and high impedance faults is poor. Thus, a comprehensive protective system is suggested at the end of the dissertation. The proposed method is based on the application of the phasor measurement unit (PMU) and the differential protection method. All of the current magnitudes and angles are collected by PMU and are sent to the phasor data concentrator (PDC), where a differential protection algorithm is applied to these data. If any fault is detected, the trip will be sent back to the corresponding circuit breakers across the network. Higher selectivity, sensitivity, and faster operation in the differential protection are superior to those of other protection schemes. Differential protection operates as unit protection, which means that it operates only when there is a fault in the protection zone. It does not function for faults occurring out of zone. Therefore, no coordination is required between differential protections across the power system. Moreover, the misoperation of this protective scheme is less likely as compared to other protection methods.

  10. IEEE 802.16J-Relay Fortified Aeromacs Networks; Benefits and Challenges

    NASA Technical Reports Server (NTRS)

    Kamali, Behnam; Apaza, Rafael D.

    2014-01-01

    Aeronautical Mobile Airport Communications System (AeroMACS) is an IEEE 802.16 standard-based (WiMAX) broadband aviation transmission technology, developed to provide safety critical communications coverage for airport surface in support of fixed and mobile ground to ground applications and services. We have previously demonstrated that IEEE 802.16j-amendment-based WiMAX is most feasible for AeroMACS applications. The principal argument in favor of application of IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified WiMAX networks, with virtually no increase in the power requirements. In this article, following introductory remarks on airport surface communications, WiMAX and AeroMACS; the IEEE 802.16j-based WiMAX technology and multihop relay systems are briefly described. The two modes of relay operation supported by IEEE 802.16j amendment; i.e., transparent (TRS) and non-transparent (NTRS) modes, are discussed in some detail. Advantages and disadvantages of using TRS and NTRS in AeroMACS networks are summarized in a table. Practical issues vis--vis the inclusion of relays in AeroMACS networks are addressed. It is argued that the selection of relay type may affect a number of network parameters. A discussion on specific benefits and challenges of inclusion of relays in AeroMACS networks is provided. The article concludes that in case it is desired or necessary to exclusively employ one type of relay mode for all applications throughout an AeroMACS network, the proper selection would be the non-transparent mode.

  11. 47 CFR 64.611 - Internet-based TRS registration.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Default provider registration. Every provider of VRS or IP Relay must, no later than December 31, 2008, provide users with the capability to register with that VRS or IP Relay provider as a “default provider.” Upon a user's registration, the VRS or IP Relay provider shall: (1) Either: (i) Facilitate the user's...

  12. 47 CFR 64.611 - Internet-based TRS registration.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Default provider registration. Every provider of VRS or IP Relay must, no later than December 31, 2008, provide users with the capability to register with that VRS or IP Relay provider as a “default provider.” Upon a user's registration, the VRS or IP Relay provider shall: (1) Either: (i) Facilitate the user's...

  13. 78 FR 56601 - Airworthiness Directives; Fokker Services B.V. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-13

    ... torque values of nuts on circuit breakers, contactors, and terminal blocks of the EPC and battery relay... blocks of the EPC and battery relay panel, as applicable; and do all applicable adjustments of the torque... contacts and nuts on circuit breakers, contactors, and terminal blocks of the EPC and battery relay panel...

  14. Understanding the Design, Function and Testing of Relays

    ERIC Educational Resources Information Center

    Adams, Roger E.; Lindbloom, Trent

    2006-01-01

    The increased use of electronics in today's automobiles has complicated the control of circuits and actuators. Manufacturers use relays to control a variety of complex circuits--for example, those involving actuators and other components like the A/C clutch, electronic cooling fans, and blower motors. Relays allow a switch or processor to control…

  15. 76 FR 3856 - Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... new relays having a GFI feature, performing certain bonding resistance measurements, and modifying... with new relays having a GFI feature, Doing certain bonding resistance measurements to verify certain... relay module assemblies and bond resistance measurements. In addition, we have reviewed Section 9 of...

  16. 78 FR 4055 - Airworthiness Directives; The Boeing Company Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-18

    ...) Installation of New Relay and Wiring Bundle Change Within 24 months after the effective date of this AD: Change... requires installing a new relay and doing certain wiring changes of the entertainment control switch. We... proposed to require installing a new relay and doing certain wiring changes of the entertainment control...

  17. 76 FR 30841 - Structure and Practices of the Video Relay Service Program; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-27

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [CG Docket No. 10-51; FCC 11-54] Structure and Practices of the Video Relay Service Program; Correction AGENCY: Federal Communications Commission. ACTION... address fraud, waste, and abuse in the Video Relay Service (VRS) industry. DATES: Effective June 1, 2011...

  18. 77 FR 18106 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-27

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [CG Docket No. 10-51; FCC 11-54] Structure and Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Final rule... adopted by the FCC to prevent fraud, waste, and abuse in the Video Relay Service (VRS) industry. DATES...

  19. 76 FR 68116 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-03

    ... Practices of the Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Interim rule... with the Commission's Structure and Practices of the Video Relay Service Program, Second Report and... announcement of the effective date of the rules. See, In the Matter of Structure and Practices of the Video...

  20. 75 FR 25255 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-07

    ... Video Relay Service Program AGENCY: Federal Communications Commission. ACTION: Notice. SUMMARY: In this... compensability from the Interstate TRS Fund (Fund) of certain types of calls made through Video Relay Service... CA, after the VRS user has initiated the video call to the CA, call back the VRS user on a voice...

  1. Cultivar and planting date selection for relay-cropping soybean with winter oilseeds

    USDA-ARS?s Scientific Manuscript database

    Double- and relay-cropping soybean with winter camelina (Camelina sativa L. Crantz) and pennycress (Thlaspi arvense L.) have been shown to be viable cropping systems for the Upper Midwest. Relaying soybean with these winter oilseeds can result in greater total seed yield (i.e., both combined) and ec...

  2. 47 CFR 74.1290 - FM translator and booster station information available on the Internet.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Additional orders by FCC (All Services) 74.28 Antenna, Directional (Aural STL/Relays) 74.536 Antenna location... frequencies (remote broadcast pickup) 74.402 Automatic relay stations (Remote pickup) 74.436 Avoidance of....1201 Directional antenna required (Aural STL/Relays) 74.536 E Emergency information Broadcasting (All...

  3. 30 CFR 75.800-2 - Approved circuit schemes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... necessary protection to the circuits required by § 75.800: (a) Ground check relays may be used for undervoltage protection if the relay coils are designed to trip the circuit breaker when line voltage decreases to 40 percent to 60 percent of the nominal line voltage; (b) Ground trip relays on resistance...

  4. 30 CFR 75.800-2 - Approved circuit schemes.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... necessary protection to the circuits required by § 75.800: (a) Ground check relays may be used for undervoltage protection if the relay coils are designed to trip the circuit breaker when line voltage decreases to 40 percent to 60 percent of the nominal line voltage; (b) Ground trip relays on resistance...

  5. 47 CFR 74.601 - Classes of TV broadcast auxiliary stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... or other purposes as authorized in § 74.631. (d) TV translator relay station. A fixed station used... translator, and to other communications facilities that the Commission may authorize or for other purposes as..., TV STL, TV relay, or TV translator relay station and retransmits them on the same frequency. [65 FR...

  6. Energy Efficiency Optimization in Relay-Assisted MIMO Systems With Perfect and Statistical CSI

    NASA Astrophysics Data System (ADS)

    Zappone, Alessio; Cao, Pan; Jorswieck, Eduard A.

    2014-01-01

    A framework for energy-efficient resource allocation in a single-user, amplify-and-forward relay-assisted MIMO system is devised in this paper. Previous results in this area have focused on rate maximization or sum power minimization problems, whereas fewer results are available when bits/Joule energy efficiency (EE) optimization is the goal. The performance metric to optimize is the ratio between the system's achievable rate and the total consumed power. The optimization is carried out with respect to the source and relay precoding matrices, subject to QoS and power constraints. Such a challenging non-convex problem is tackled by means of fractional programming and and alternating maximization algorithms, for various CSI assumptions at the source and relay. In particular the scenarios of perfect CSI and those of statistical CSI for either the source-relay or the relay-destination channel are addressed. Moreover, sufficient conditions for beamforming optimality are derived, which is useful in simplifying the system design. Numerical results are provided to corroborate the validity of the theoretical findings.

  7. Multi-pair two-way massive MIMO AF relaying with ZFR/ZFT beamforming and imperfect CSI over ricean fading channels

    NASA Astrophysics Data System (ADS)

    Xu, Kui; Sun, Xiaoli; Zhang, Dongmei

    2016-10-01

    This paper investigates the spectral and energy efficiencies of a multi-pair two-way amplify-and-forward (AF) relay system over Ricean fading channels, where multiple user-pairs exchange information within pair through a relay with very large number of antennas, while each user equipped with a single antenna. Firstly, beamforming matrixe of zero-forcing reception/zero-forcing transmission (ZFR/ZFT) with imperfect channel state information (CSI) at the relay is given. Then, the unified asymptotic signal-to-interference-plus-noise ratio (SINR) expressions with imperfect CSI are obtained analytically. Finally, two power scaling schemes are proposed and the asymptotic spectral and energy efficiencies based on the proposed power scaling schemes are derived and verified by the Monte-Carlo simulations. Theoretical analyses and simulation results show that with imperfect CSI, if the number of relay antennas grows asymptotically large, we need cut down the transmit power of each user and relay to different proportion when the Ricean K-factor is non-zero and zero (Rayleigh fading) in order to maintain a desirable rate.

  8. Mapping Interactions between Myosin Relay and Converter Domains That Power Muscle Function*

    PubMed Central

    Kronert, William A.; Melkani, Girish C.; Melkani, Anju; Bernstein, Sanford I.

    2014-01-01

    Intramolecular communication within myosin is essential for its function as motor, but the specific amino acid residue interactions required are unexplored within muscle cells. Using Drosophila melanogaster skeletal muscle myosin, we performed a novel in vivo molecular suppression analysis to define the importance of three relay loop amino acid residues (Ile508, Asn509, and Asp511) in communicating with converter domain residue Arg759. We found that the N509K relay mutation suppressed defects in myosin ATPase, in vitro motility, myofibril stability, and muscle function associated with the R759E converter mutation. Through molecular modeling, we define a mechanism for this interaction and suggest why the I508K and D511K relay mutations fail to suppress R759E. Interestingly, I508K disabled motor function and myofibril assembly, suggesting that productive relay-converter interaction is essential for both processes. We conclude that the putative relay-converter interaction mediated by myosin residues 509 and 759 is critical for the biochemical and biophysical function of skeletal muscle myosin and the normal ultrastructural and mechanical properties of muscle. PMID:24627474

  9. EAGLE: relay mirror technology development

    NASA Astrophysics Data System (ADS)

    Hartman, Mary; Restaino, Sergio R.; Baker, Jeffrey T.; Payne, Don M.; Bukley, Jerry W.

    2002-06-01

    EAGLE (Evolutionary Air & Space Global Laser Engagement) is the proposed high power weapon system with a high power laser source, a relay mirror constellation, and the necessary ground and communications links. The relay mirror itself will be a satellite composed of two optically-coupled telescopes/mirrors used to redirect laser energy from ground, air, or space based laser sources to distant points on the earth or space. The receiver telescope captures the incoming energy, relays it through an optical system that cleans up the beam, then a separate transmitter telescope/mirror redirects the laser energy at the desired target. Not only is it a key component in extending the range of DoD's current laser weapon systems, it also enables ancillary missions. Furthermore, if the vacuum of space is utilized, then the atmospheric effects on the laser beam propagation will be greatly attenuated. Finally, several critical technologies are being developed to make the EAGLE/Relay Mirror concept a reality, and the Relay Mirror Technology Development Program was set up to address them. This paper will discuss each critical technology, the current state of the work, and the future implications of this program.

  10. Frequency-selective REDOR and spin-diffusion relays in uniformly labeled whole cells.

    PubMed

    Rice, David M; Romaniuk, Joseph A H; Cegelski, Lynette

    2015-11-01

    Solid-state NMR is a powerful and non-perturbative method to measure and define chemical composition and architecture in bacterial cell walls, even in the context of whole cells. Most NMR studies on whole cells have used selectively labeled samples. Here, we introduce an NMR sequence relay using frequency-selective REDOR (fsREDOR) and spin diffusion elements to probe a unique amine contribution in uniformly (13)C- and (15)N-labeled Staphylococcus aureus whole cells that we attribute to the d-alanine of teichoic acid. In addition to the primary peptidoglycan structural scaffold, cell walls can contain significant amounts of teichoic acid that contribute to cell-wall function. When incorporated into teichoic acid, d-alanine is present as an ester, connected via its carbonyl to a ribitol carbon, and thus has a free amine. Teichoic acid d-Ala is removed during cell-wall isolations and can only be detected in the context of whole cells. The sequence presented here begins with fsREDOR and a chemical shift evolution period for 2D data acquisition, followed by DARR spin diffusion and then an additional fsREDOR period. fsREDOR elements were used for (13)C observation to avoid complications from (13)C-(13)C couplings due to uniform labeling and for (15)N dephasing to achieve selectivity in the nitrogens serving as dephasers. The results show that the selected amine nitrogen of interest is near to teichoic acid ribitol carbons and also the methyl group carbon associated with alanine. In addition, its carbonyl is not significantly dephased by amide nitrogens, consistent with the expected microenvironment around teichoic acid. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Enhanced Positioning Algorithm of ARPS for Improving Accuracy and Expanding Service Coverage

    PubMed Central

    Lee, Kyuman; Baek, Hoki; Lim, Jaesung

    2016-01-01

    The airborne relay-based positioning system (ARPS), which employs the relaying of navigation signals, was proposed as an alternative positioning system. However, the ARPS has limitations, such as relatively large vertical error and service restrictions, because firstly, the user position is estimated based on airborne relays that are located in one direction, and secondly, the positioning is processed using only relayed navigation signals. In this paper, we propose an enhanced positioning algorithm to improve the performance of the ARPS. The main idea of the enhanced algorithm is the adaptable use of either virtual or direct measurements of reference stations in the calculation process based on the structural features of the ARPS. Unlike the existing two-step algorithm for airborne relay and user positioning, the enhanced algorithm is divided into two cases based on whether the required number of navigation signals for user positioning is met. In the first case, where the number of signals is greater than four, the user first estimates the positions of the airborne relays and its own initial position. Then, the user position is re-estimated by integrating a virtual measurement of a reference station that is calculated using the initial estimated user position and known reference positions. To prevent performance degradation, the re-estimation is performed after determining its requirement through comparing the expected position errors. If the navigation signals are insufficient, such as when the user is outside of airborne relay coverage, the user position is estimated by additionally using direct signal measurements of the reference stations in place of absent relayed signals. The simulation results demonstrate that a higher accuracy level can be achieved because the user position is estimated based on the measurements of airborne relays and a ground station. Furthermore, the service coverage is expanded by using direct measurements of reference stations for user positioning. PMID:27529252

  12. Enhanced Positioning Algorithm of ARPS for Improving Accuracy and Expanding Service Coverage.

    PubMed

    Lee, Kyuman; Baek, Hoki; Lim, Jaesung

    2016-08-12

    The airborne relay-based positioning system (ARPS), which employs the relaying of navigation signals, was proposed as an alternative positioning system. However, the ARPS has limitations, such as relatively large vertical error and service restrictions, because firstly, the user position is estimated based on airborne relays that are located in one direction, and secondly, the positioning is processed using only relayed navigation signals. In this paper, we propose an enhanced positioning algorithm to improve the performance of the ARPS. The main idea of the enhanced algorithm is the adaptable use of either virtual or direct measurements of reference stations in the calculation process based on the structural features of the ARPS. Unlike the existing two-step algorithm for airborne relay and user positioning, the enhanced algorithm is divided into two cases based on whether the required number of navigation signals for user positioning is met. In the first case, where the number of signals is greater than four, the user first estimates the positions of the airborne relays and its own initial position. Then, the user position is re-estimated by integrating a virtual measurement of a reference station that is calculated using the initial estimated user position and known reference positions. To prevent performance degradation, the re-estimation is performed after determining its requirement through comparing the expected position errors. If the navigation signals are insufficient, such as when the user is outside of airborne relay coverage, the user position is estimated by additionally using direct signal measurements of the reference stations in place of absent relayed signals. The simulation results demonstrate that a higher accuracy level can be achieved because the user position is estimated based on the measurements of airborne relays and a ground station. Furthermore, the service coverage is expanded by using direct measurements of reference stations for user positioning.

  13. Bubbling in delay-coupled lasers.

    PubMed

    Flunkert, V; D'Huys, O; Danckaert, J; Fischer, I; Schöll, E

    2009-06-01

    We theoretically study chaos synchronization of two lasers which are delay coupled via an active or a passive relay. While the lasers are synchronized, their dynamics is identical to a single laser with delayed feedback for a passive relay and identical to two delay-coupled lasers for an active relay. Depending on the coupling parameters the system exhibits bubbling, i.e., noise-induced desynchronization, or on-off intermittency. We associate the desynchronization dynamics in the coherence collapse and low-frequency fluctuation regimes with the transverse instability of some of the compound cavity's antimodes. Finally, we demonstrate how, by using an active relay, bubbling can be suppressed.

  14. Lessons Learned from Coordinating Relay Activities at Mars

    NASA Technical Reports Server (NTRS)

    Gladden, Roy E.; Hwang, Pauline; Waggoner, Bruce; McLaughlin, Bruce; Fieseler, Paul; Thomas, Reid; Bigwood, Maria; Herrera, Paul

    2005-01-01

    The Mission Management Office at the Jet Propulsion Laboratory was tasked with coordinating the relay of data between multiple spacecraft at Mars in support of the Mars Exploration Rover Missions in early 2004. The confluence of three orbiters (Mars Global Surveyor, Mars Odyssey, and Mars Express), two rovers (Spirit and Opportunity), and one lander (Beagle 2) has provided a challenging operational scenario that required careful coordination between missions to provide the necessary support and to avoid potential interference during simultaneous relay sessions. As these coordination efforts progressed, several important lessons were learned that should be applied to future Mars relay activities.

  15. Innovation Relay: Empowering School Nurses to Find New Solutions for Old Problems.

    PubMed

    Maughan, Erin D; Galemore, Cynthia; Mattey, Beth

    2016-09-01

    NASN's 48th Annual School Nurse Conference-Learning, Linking, Leading-included the first ever innovation relay contest. The relay was based on a design developed by the Institute of Healthcare Improvement's Innovation Relay. Participation included 43 contestants from 16 states and one foreign country. Teams were given 24 hours to develop a solution. This article describes the process utilized, the problem introduced, and a brief synopsis of each team's solution. The ongoing purpose of the exercise is to encourage innovation by school nurses as they experience student health-related barriers in the academic setting. © 2016 The Author(s).

  16. Heat analysis of thermal overload relays using 3-D finite element method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kawase, Yoshihiro; Ichihashi, Takayuki; Ito, Shokichi

    1999-05-01

    In designing a thermal overload relay, it is necessary to analyze thermal characteristics of several trial models. Up to now, this has been done by measuring the temperatures on a number of positions in the trial models. This experimental method is undoubtedly expensive. In this paper, the temperature distribution of a thermal overload relay is obtained by using 3-D finite element analysis taking into account the current distribution in current-carrying conductors. It is shown that the 3-D analysis is capable of evaluating a new design of thermal overload relays.

  17. Mission Management Computer and Sequencing Hardware for RLV-TD HEX-01 Mission

    NASA Astrophysics Data System (ADS)

    Gupta, Sukrat; Raj, Remya; Mathew, Asha Mary; Koshy, Anna Priya; Paramasivam, R.; Mookiah, T.

    2017-12-01

    Reusable Launch Vehicle-Technology Demonstrator Hypersonic Experiment (RLV-TD HEX-01) mission posed some unique challenges in the design and development of avionics hardware. This work presents the details of mission critical avionics hardware mainly Mission Management Computer (MMC) and sequencing hardware. The Navigation, Guidance and Control (NGC) chain for RLV-TD is dual redundant with cross-strapped Remote Terminals (RTs) interfaced through MIL-STD-1553B bus. MMC is Bus Controller on the 1553 bus, which does the function of GPS aided navigation, guidance, digital autopilot and sequencing for the RLV-TD launch vehicle in different periodicities (10, 20, 500 ms). Digital autopilot execution in MMC with a periodicity of 10 ms (in ascent phase) is introduced for the first time and successfully demonstrated in the flight. MMC is built around Intel i960 processor and has inbuilt fault tolerance features like ECC for memories. Fault Detection and Isolation schemes are implemented to isolate the failed MMC. The sequencing hardware comprises Stage Processing System (SPS) and Command Execution Module (CEM). SPS is `RT' on the 1553 bus which receives the sequencing and control related commands from MMCs and posts to downstream modules after proper error handling for final execution. SPS is designed as a high reliability system by incorporating various fault tolerance and fault detection features. CEM is a relay based module for sequence command execution.

  18. Connectivity Restoration in Wireless Sensor Networks via Space Network Coding.

    PubMed

    Uwitonze, Alfred; Huang, Jiaqing; Ye, Yuanqing; Cheng, Wenqing

    2017-04-20

    The problem of finding the number and optimal positions of relay nodes for restoring the network connectivity in partitioned Wireless Sensor Networks (WSNs) is Non-deterministic Polynomial-time hard (NP-hard) and thus heuristic methods are preferred to solve it. This paper proposes a novel polynomial time heuristic algorithm, namely, Relay Placement using Space Network Coding (RPSNC), to solve this problem, where Space Network Coding, also called Space Information Flow (SIF), is a new research paradigm that studies network coding in Euclidean space, in which extra relay nodes can be introduced to reduce the cost of communication. Unlike contemporary schemes that are often based on Minimum Spanning Tree (MST), Euclidean Steiner Minimal Tree (ESMT) or a combination of MST with ESMT, RPSNC is a new min-cost multicast space network coding approach that combines Delaunay triangulation and non-uniform partitioning techniques for generating a number of candidate relay nodes, and then linear programming is applied for choosing the optimal relay nodes and computing their connection links with terminals. Subsequently, an equilibrium method is used to refine the locations of the optimal relay nodes, by moving them to balanced positions. RPSNC can adapt to any density distribution of relay nodes and terminals, as well as any density distribution of terminals. The performance and complexity of RPSNC are analyzed and its performance is validated through simulation experiments.

  19. Real time testing of intelligent relays for synchronous distributed generation islanding detection

    NASA Astrophysics Data System (ADS)

    Zhuang, Davy

    As electric power systems continue to grow to meet ever-increasing energy demand, their security, reliability, and sustainability requirements also become more stringent. The deployment of distributed energy resources (DER), including generation and storage, in conventional passive distribution feeders, gives rise to integration problems involving protection and unintentional islanding. Distributed generators need to be islanded for safety reasons when disconnected or isolated from the main feeder as distributed generator islanding may create hazards to utility and third-party personnel, and possibly damage the distribution system infrastructure, including the distributed generators. This thesis compares several key performance indicators of a newly developed intelligent islanding detection relay, against islanding detection devices currently used by the industry. The intelligent relay employs multivariable analysis and data mining methods to arrive at decision trees that contain both the protection handles and the settings. A test methodology is developed to assess the performance of these intelligent relays on a real time simulation environment using a generic model based on a real-life distribution feeder. The methodology demonstrates the applicability and potential advantages of the intelligent relay, by running a large number of tests, reflecting a multitude of system operating conditions. The testing indicates that the intelligent relay often outperforms frequency, voltage and rate of change of frequency relays currently used for islanding detection, while respecting the islanding detection time constraints imposed by standing distributed generator interconnection guidelines.

  20. Coding, modulation, and relays for deep space communication Mars Rovers Case Study

    NASA Technical Reports Server (NTRS)

    Statman, Joseph I.; Edwards, Charles D.

    2004-01-01

    This paper presents the communications challenges for the MER mission, the use of DSN and MER tools to maximize the science return, and the application of standards-based relays to the problem. To date, more than 90% of the data returned from MER has been returned via relays, not direct-to-Earath (DTE).

  1. 76 FR 47424 - Airworthiness Directives; Dassault Aviation Model FALCON 7X Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-05

    ... (HSTA) electric motors reversion relays (installed with M1235 and M1236), has been developed and must be... operational test of the HSTA electric motors reversion relays. For aeroplanes equipped with HSECU P/N 051244... operational test of the HSTA electric motors reversion relays is 1,850 flight hours after accomplishment of...

  2. Torque control for electric motors

    NASA Technical Reports Server (NTRS)

    Bernard, C. A.

    1980-01-01

    Method for adjusting electric-motor torque output to accomodate various loads utilizes phase-lock loop to control relay connected to starting circuit. As load is imposed, motor slows down, and phase lock is lost. Phase-lock signal triggers relay to power starting coil and generate additional torque. Once phase lock is recoverd, relay restores starting circuit to its normal operating mode.

  3. 76 FR 52899 - Airworthiness Directives; The Boeing Company Model 767-200, -300, and -300F Series Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... the compliance times specified, unless already done. Installation of New Relay and Wiring Bundle (g... certain wiring changes, installing a new relay and necessary wiring in the cabin air conditioning and... for changing the wire bundle route and wiring, installing a new relay and applicable wiring in the...

  4. 76 FR 11462 - Consumer and Governmental Affairs Bureau Seeks Comment on Application of New and Emerging...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... Affairs Bureau Seeks Comment on Application of New and Emerging Technologies for Video Relay Service Use... seeks comment regarding new and emerging technologies that may be used to access Video Relay Service... Video Relay Service Use, Public Notice, document DA 11-317, released on February 17, 2011, in CG Docket...

  5. Effects of Distributed Generation on Overcurrent Relay Coordination and an Adaptive Protection Scheme

    NASA Astrophysics Data System (ADS)

    Ilik, Semih C.; Arsoy, Aysen B.

    2017-07-01

    Integration of distributed generation (DG) such as renewable energy sources to electrical network becomes more prevalent in recent years. Grid connection of DG has effects on load flow directions, voltage profile, short circuit power and especially protection selectivity. Applying traditional overcurrent protection scheme is inconvenient when system reliability and sustainability are considered. If a fault happens in DG connected network, short circuit contribution of DG, creates additional branch element feeding the fault current; compels to consider directional overcurrent (OC) protection scheme. Protection coordination might get lost for changing working conditions when DG sources are connected. Directional overcurrent relay parameters are determined for downstream and upstream relays when different combinations of DG connected singular or plural, on radial test system. With the help of proposed flow chart, relay parameters are updated and coordination between relays kept sustained for different working conditions in DigSILENT PowerFactory program.

  6. Offshore suspension relaying to reduce levels of Vibrio vulnificus in oysters (Crassostrea virginica).

    PubMed

    Motes, M L; DePaola, A

    1996-10-01

    Oysters naturally contaminated with 10(3) to 10(4) most probable numbers (MPN) of Vibrio vulnificus per g were relayed to offshore waters (salinity, 30 to 34 ppt), where they were suspended in racks at a depth of 7.6 m. V. vulnificus counts in oysters were reduced to < 10 MPN/g within 7 to 17 days in five of the six studies. At the end of the studies (17 to 49 days), V. vulnificus levels were reduced further and ranged from a mean of 0.23 to 2.6 MPN/g. Oyster mortalities during relaying were < 6%. The reduction of V. vulnificus in relayed oysters is associated with exposure to high-salinity environments essentially devoid of V. vulnificus. Offshore suspension relaying may be a method that industry can employ to reduce V. vulnificus levels in raw Gulf Coast oysters.

  7. Relay kidney transplantation in Korea--legal, ethical and medical aspects.

    PubMed

    Park, Jong-Hyun; Park, Joong-Won; Koo, Young-Mo; Kim, Jang Han

    2004-07-01

    Living kidney transplantations constitute the majority of kidney transplantations in Korea. Recently, relay kidney transplantation, which is a modified form of both 'exchange transplantation' and 'living anonymous donation', has become at issue. After a living anonymous donor makes the initial donation, the next donor, who is related to the first recipient, makes the second donation; the third donor, who is related to the second recipient, makes the third donation; and so on. In relay kidney transplantation, organ trafficking, coercion of donation, assessment order, breach of agreement, and recipient burden should be evaluated with respect to ethical, legal and medical considerations. Despite these problems, a non-governmental body, the Korean Organ and Tissue Donor Program, has been promoting relay kidney transplantations to address the shortage of cadaveric kidney donations. Acceptance of the method of relay kidney transplantation requires the institution of supplementary measures to minimize the related problems.

  8. GPS/REFSAT definition study report for low-cost terminals

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A relay transponder, located either on a satellite in geostationary orbit or on a local tower to relay acquisition-aiding data, ephemerides, etc, from a ground-based remote control station to a GPS civil user terminal located on a ship or land-transportation vehicle is described. Termed REFSAT (Reference Satellite), this concept reduces the circuit complexity and cost of user terminals. The various systems needed to implement the REFSAT concept for low-cost, GPS civil terminals are defined. The GPS/REFSAT system compatible with the NAVSTAR GPS system consists of a geostationary relay satellite, civil user terminals, and the central facility which performs operations common to all users for relay via the space segment. A GPS/REFSAT system utilizing a local tower for the relay transponder is described, results of a study of civil user requirements are presented, and specifications for the GPS/REFSAT system and its individual segments are included.

  9. Development of an adaptive optics test-bed for relay mirror applications

    NASA Astrophysics Data System (ADS)

    Mansell, Justin D.; Jacobs, Arturo A.; Maynard, Morris

    2005-08-01

    The relay mirror concept involves deploying a passive optical station at a high altitude for relaying a beam from a laser weapon to a target. Relay mirrors have been proposed as a method of increasing the range of laser weapons that is less costly than deploying a larger number of laser weapons. Relay mirrors will only be effective if the beam spreading and beam quality degradation induced by atmospheric aberrations and thermal blooming can be mitigated. In this paper we present the first phase of a multi-year effort to develop a theoretical and experimental capability at Boeing-SVS to study these problems. A team from MZA and Boeing-SVS has developed a laboratory test-bed consisting of a distributed atmospheric path simulated by three liquid crystal phase screens, a Shack-Hartmann wavefront sensor, and a MEMS membrane deformable mirror. We present results of AO component calibration and evaluation, the system construction, and the system performance.

  10. Phospholipase C-β4 Is Essential for the Progression of the Normal Sleep Sequence and Ultradian Body Temperature Rhythms in Mice

    PubMed Central

    Ikeda, Masayuki; Hirono, Moritoshi; Sugiyama, Takashi; Moriya, Takahiro; Ikeda-Sagara, Masami; Eguchi, Naomi; Urade, Yoshihiro; Yoshioka, Tohru

    2009-01-01

    Background The sleep sequence: i) non-REM sleep, ii) REM sleep, and iii) wakefulness, is stable and widely preserved in mammals, but the underlying mechanisms are unknown. It has been shown that this sequence is disrupted by sudden REM sleep onset during active wakefulness (i.e., narcolepsy) in orexin-deficient mutant animals. Phospholipase C (PLC) mediates the signaling of numerous metabotropic receptors, including orexin receptors. Among the several PLC subtypes, the β4 subtype is uniquely localized in the geniculate nucleus of thalamus which is hypothesized to have a critical role in the transition and maintenance of sleep stages. In fact, we have reported irregular theta wave frequency during REM sleep in PLC-β4-deficient mutant (PLC-β4−/−) mice. Daily behavioral phenotypes and metabotropic receptors involved have not been analyzed in detail in PLC-β4−/− mice, however. Methodology/Principal Findings Therefore, we analyzed 24-h sleep electroencephalogram in PLC-β4−/− mice. PLC-β4−/− mice exhibited normal non-REM sleep both during the day and nighttime. PLC-β4−/− mice, however, exhibited increased REM sleep during the night, their active period. Also, their sleep was fragmented with unusual wake-to-REM sleep transitions, both during the day and nighttime. In addition, PLC-β4−/− mice reduced ultradian body temperature rhythms and elevated body temperatures during the daytime, but had normal homeothermal response to acute shifts in ambient temperatures (22°C–4°C). Within the most likely brain areas to produce these behavioral phenotypes, we found that, not orexin, but group-1 metabotropic glutamate receptor (mGluR)-mediated Ca2+ mobilization was significantly reduced in the dorsal lateral geniculate nucleus (LGNd) of PLC-β4−/− mice. Voltage clamp recordings revealed that group-1 mGluR-mediated currents in LGNd relay neurons (inward in wild-type mice) were outward in PLC-β4−/− mice. Conclusions/Significance These lines of evidence indicate that impaired LGNd relay, possibly mediated via group-1 mGluR, may underlie irregular sleep sequences and ultradian body temperature rhythms in PLC-β4−/− mice. PMID:19898623

  11. Bilayer Protograph Codes for Half-Duplex Relay Channels

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; VanNguyen, Thuy; Nosratinia, Aria

    2013-01-01

    Direct to Earth return links are limited by the size and power of lander devices. A standard alternative is provided by a two-hops return link: a proximity link (from lander to orbiter relay) and a deep-space link (from orbiter relay to Earth). Although direct to Earth return links are limited by the size and power of lander devices, using an additional link and a proposed coding for relay channels, one can obtain a more reliable signal. Although significant progress has been made in the relay coding problem, existing codes must be painstakingly optimized to match to a single set of channel conditions, many of them do not offer easy encoding, and most of them do not have structured design. A high-performing LDPC (low-density parity-check) code for the relay channel addresses simultaneously two important issues: a code structure that allows low encoding complexity, and a flexible rate-compatible code that allows matching to various channel conditions. Most of the previous high-performance LDPC codes for the relay channel are tightly optimized for a given channel quality, and are not easily adapted without extensive re-optimization for various channel conditions. This code for the relay channel combines structured design and easy encoding with rate compatibility to allow adaptation to the three links involved in the relay channel, and furthermore offers very good performance. The proposed code is constructed by synthesizing a bilayer structure with a pro to graph. In addition to the contribution to relay encoding, an improved family of protograph codes was produced for the point-to-point AWGN (additive white Gaussian noise) channel whose high-rate members enjoy thresholds that are within 0.07 dB of capacity. These LDPC relay codes address three important issues in an integrative manner: low encoding complexity, modular structure allowing for easy design, and rate compatibility so that the code can be easily matched to a variety of channel conditions without extensive re-optimization. The main problem of half-duplex relay coding can be reduced to the simultaneous design of two codes at two rates and two SNRs (signal-to-noise ratios), such that one is a subset of the other. This problem can be addressed by forceful optimization, but a clever method of addressing this problem is via the bilayer lengthened (BL) LDPC structure. This method uses a bilayer Tanner graph to make the two codes while using a concept of "parity forwarding" with subsequent successive decoding that removes the need to directly address the issue of uneven SNRs among the symbols of a given codeword. This method is attractive in that it addresses some of the main issues in the design of relay codes, but it does not by itself give rise to highly structured codes with simple encoding, nor does it give rate-compatible codes. The main contribution of this work is to construct a class of codes that simultaneously possess a bilayer parity- forwarding mechanism, while also benefiting from the properties of protograph codes having an easy encoding, a modular design, and being a rate-compatible code.

  12. Sedimentary record of relay zone evolution, Central Corinth Rift (Greece): Role of fault propagation and structural inheritance.

    NASA Astrophysics Data System (ADS)

    Hemelsdaël, Romain; Ford, Mary; Meyer, Nicolas

    2013-04-01

    Relay zones along rift border fault systems form topographic lows that are considered to allow the transfer of sediment from the footwall into hanging wall depocentres. Present knowledge focuses on the modifications of drainage patterns and sediment pathways across relay zones, however their vertical motion during growth and interaction of faults segments is not well documented. 3D models of fault growth and linkage are also under debate. The Corinth rift (Greece) is an ideal natural laboratory for the study of fault system evolution. Fault activity and rift depocentres migrated northward during Pliocene to Recent N-S extension. We report on the evolution of a relay zone in the currently active southern rift margin fault system from Pleistocene to present-day. The relay zone lies between the E-W East Helike (EHF) and Derveni faults (DF) that lie just offshore and around the town of Akrata. During its evolution the relay zone captured the antecedent Krathis river which continued to deposit Gilbert-type deltas across the relay zone during fault interaction, breaching and post linkage phases. Moreover our work underlines the role that pre-existing structure in the location of the transfer zone. Offshore fault geometry and kinematics, and sediment distribution were defined by interpretation and depth conversion of high resolution seismic profiles (from Maurice Ewing 2001 geophysical survey). Early lateral propagation of the EHF is recorded by synsedimentary fault propagation folds while the DF records tilted block geometries since initiation. Within the relay zone beds are gradually tilted toward the basin before breaching. These different styles of deformation highlight mechanical contrasts and upper crustal partition associated with the development of the Akrata relay zone. Onshore detailed lithostratigraphy, structure and geomorphological features record sedimentation across the subsiding relay ramp and subsequent footwall uplift after breaching. The area is characterised by the successive deposition of the northward prograding Platanos Gilbert-type delta (Middle group; deposited in hangingwall of the Pirgaki-Mamoussia fault) and the NE to E prograding Akrata Gilbert-type delta (Upper group). The Akrata Gilbert-type delta records progressive rotation and lengthening of the relay ramp as the East Helike fault and Derveni fault propagated laterally (from around 0.8 Ma) and started to overlap. The relay ramp was then breached by the Krathis fault (around 0.45 Ma) and the latter reactivated a NW-SE oriented inherited structure. Onshore-offshore correlation and profile restoration of the Upper group demonstrate the presence of this pre-existing structure (detachment fault?) below the Akrata relay zone that was responsible for significant eastward thickening in early rift sediments (Lower to Middle group). Our evolution model is consistent with the 'isolated fault' model where a fault array initially develops from growth of kinematically independent fault segments and fault displacement gradually accumulates during pre- and post-linkage stages. Despite the prominent control of pre-existing fabrics on the location of the transfer zone, lateral fault propagation and interaction can be well documented.

  13. Libration Point Navigation Concepts Supporting the Vision for Space Exploration

    NASA Technical Reports Server (NTRS)

    Carpenter, J. Russell; Folta, David C.; Moreau, Michael C.; Quinn, David A.

    2004-01-01

    This work examines the autonomous navigation accuracy achievable for a lunar exploration trajectory from a translunar libration point lunar navigation relay satellite, augmented by signals from the Global Positioning System (GPS). We also provide a brief analysis comparing the libration point relay to lunar orbit relay architectures, and discuss some issues of GPS usage for cis-lunar trajectories.

  14. Teach for America, Relay Graduate School, and the Charter School Networks: The Making of a Parallel Education Structure

    ERIC Educational Resources Information Center

    Mungal, Angus Shiva

    2016-01-01

    In New York City, a partnership between Teach For America (TFA), the New York City Department of Education (NYCDOE), the Relay Graduate School of Education (Relay), and three charter school networks produced a "parallel education structure" within the public school system. Driving the partnership and the parallel education structure are…

  15. 78 FR 64976 - Notice of Intent To Prepare an Environmental Impact Statement and Public Scoping Meetings for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-30

    ... telecommunications device for the deaf may call the Federal Relay Service (FedRelay) at 1-800-877- 8339 TTY/ASCII to contact the above individual during normal business hours. The FedRelay is available 24 hours a day, 7.... Groundwater Storage; 5. Habitat/Watershed Protection and Enhancement; 6. Enhanced Water Conservation; and 7...

  16. 78 FR 64975 - Notice of Intent To Prepare an Environmental Impact Statement and Public Scoping Meetings for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-30

    ... the deaf may call the Federal Relay Service (FedRelay) at 1-800-877- 8339 TTY/ASCII to contact the above individual during normal business hours. The FedRelay is available 24 hours a day, 7 days a week...; 5. Habitat/Watershed Protection and Enhancement; 6. Enhanced Water Conservation; and 7. Market...

  17. Laser Communications Relay Demonstration (LCRD) Update and the Path Towards Optical Relay Operations

    NASA Technical Reports Server (NTRS)

    Israel, David J.; Edwards, Bernard L.; Staren, John W.

    2017-01-01

    This paper provides a concept for an evolution of NASA's optical communications near Earth relay architecture. NASA's Laser Communications Relay Demonstration (LCRD), a joint project between NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory - California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT LL). LCRD will provide a minimum of two years of high data rate optical communications service experiments in geosynchronous orbit (GEO), following launch in 2019. This paper will provide an update of the LCRD mission status and planned capabilities and experiments, followed by a discussion of the path from LCRD to operational network capabilities.

  18. Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks.

    PubMed

    Lee, Jong-Ho; Sohn, Illsoo; Kim, Yong-Hwa

    2017-05-16

    In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF) relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks.

  19. Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks

    PubMed Central

    Lee, Jong-Ho; Sohn, Illsoo; Kim, Yong-Hwa

    2017-01-01

    In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF) relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks. PMID:28509841

  20. Development of a hybrid microelectronics solid state relay for 2500 volts isolation and minus 120 C to 80 C thermal cycling range

    NASA Technical Reports Server (NTRS)

    Sater, B. L.; Riley, T. J.; Janssen, W.

    1973-01-01

    A hybrid microelectronics solid state relay was developed in a TO-116 package for the MINX project. The relay provides 2500 Vdc input to output isolation and operated from a MHTL logic signal to switch a load of 400 Vdc at 2 mA. The relay is designed to operate in space and survive 1000 thermal cycles of 120 C to 80 C. The use of X-rays for failure analysis in small hybrid circuits proved valuable and the applications of vacuum deposited Parylene as a dielectric coating proved extremely valuable.

  1. Laser Communications Relay Demonstration (LCRD) Update and the Path Towards Optical Relay Operations

    NASA Technical Reports Server (NTRS)

    Israel, David J.; Edwards, Bernard L.; Staren, John W.

    2017-01-01

    This Presentation provides a concept for an evolution of NASAs optical communications near Earth relay architecture. NASA's Laser Communications Relay Demonstration (LCRD), a joint project between NASAs Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory - California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT LL). LCRD will provide a minimum of two years of high data rate optical communications service experiments in geosynchronous orbit (GEO), following launch in 2019. This paper will provide an update of the LCRD mission status and planned capabilities and experiments, followed by a discussion of the path from LCRD to operational network capabilities.

  2. Downlink Cooperative Broadcast Transmission Based on Superposition Coding in a Relaying System for Future Wireless Sensor Networks.

    PubMed

    Liu, Yang; Han, Guangjie; Shi, Sulong; Li, Zhengquan

    2018-06-20

    This study investigates the superiority of cooperative broadcast transmission over traditional orthogonal schemes when applied in a downlink relaying broadcast channel (RBC). Two proposed cooperative broadcast transmission protocols, one with an amplify-and-forward (AF) relay, and the other with a repetition-based decode-and-forward (DF) relay, are investigated. By utilizing superposition coding (SupC), the source and the relay transmit the private user messages simultaneously instead of sequentially as in traditional orthogonal schemes, which means the channel resources are reused and an increased channel degree of freedom is available to each user, hence the half-duplex penalty of relaying is alleviated. To facilitate a performance evaluation, theoretical outage probability expressions of the two broadcast transmission schemes are developed, based on which, we investigate the minimum total power consumption of each scheme for a given traffic requirement by numerical simulation. The results provide details on the overall system performance and fruitful insights on the essential characteristics of cooperative broadcast transmission in RBCs. It is observed that better overall outage performances and considerable power gains can be obtained by utilizing cooperative broadcast transmissions compared to traditional orthogonal schemes.

  3. RoCoMAR: robots' controllable mobility aided routing and relay architecture for mobile sensor networks.

    PubMed

    Le, Duc Van; Oh, Hoon; Yoon, Seokhoon

    2013-07-05

    In a practical deployment, mobile sensor network (MSN) suffers from a low performance due to high node mobility, time-varying wireless channel properties, and obstacles between communicating nodes. In order to tackle the problem of low network performance and provide a desired end-to-end data transfer quality, in this paper we propose a novel ad hoc routing and relaying architecture, namely RoCoMAR (Robots' Controllable Mobility Aided Routing) that uses robotic nodes' controllable mobility. RoCoMAR repeatedly performs link reinforcement process with the objective of maximizing the network throughput, in which the link with the lowest quality on the path is identified and replaced with high quality links by placing a robotic node as a relay at an optimal position. The robotic node resigns as a relay if the objective is achieved or no more gain can be obtained with a new relay. Once placed as a relay, the robotic node performs adaptive link maintenance by adjusting its position according to the movements of regular nodes. The simulation results show that RoCoMAR outperforms existing ad hoc routing protocols for MSN in terms of network throughput and end-to-end delay.

  4. Implementation of Pass Through PPTP Relay System with Authentication at Each Gateway and Its Performance Evaluations

    NASA Astrophysics Data System (ADS)

    Saito, Shoichi; Uehara, Tetsutaro; Izumi, Yutaka; Kunieda, Yoshitoshi

    The VPN (Virtual Private Network) technique becomes more and more popular to protect contents of messages and to achieve secure communication from incidents, such as tapping. However, it grow in usage that a VPN server is used on a sub-network in part of an office-wide network. But, a PPTP system included in Windows operating systems cannot establish nested VPN links. Moreover encrypted communication by VPN hides a user of the VPN connection. Consequently, any administrators of network systems can’t find out the users of the VPN connection via firewall, moreover can’t decide whether if the user is legal or not. In order to solve this problem, we developed a multi step PPTP relay system on a firewall. This system solves all the problems of our previously developed PPTP relay system(1). The new relay system improves security by encrypting through the whole end-to-end communication and abolishing of prior registration of passwords for the next step. Furthermore, transport speed is accelerated, and the restriction of the number of steps on relay is also abolished. By these features the multi step PPTP relay system expands usability.

  5. Topological Interference Management for K-User Downlink Massive MIMO Relay Network Channel.

    PubMed

    Selvaprabhu, Poongundran; Chinnadurai, Sunil; Li, Jun; Lee, Moon Ho

    2017-08-17

    In this paper, we study the emergence of topological interference alignment and the characterizing features of a multi-user broadcast interference relay channel. We propose an alternative transmission strategy named the relay space-time interference alignment (R-STIA) technique, in which a K -user multiple-input-multiple-output (MIMO) interference channel has massive antennas at the transmitter and relay. Severe interference from unknown transmitters affects the downlink relay network channel and degrades the system performance. An additional (unintended) receiver is introduced in the proposed R-STIA technique to overcome the above problem, since it has the ability to decode the desired signals for the intended receiver by considering cooperation between the receivers. The additional receiver also helps in recovering and reconstructing the interference signals with limited channel state information at the relay (CSIR). The Alamouti space-time transmission technique and minimum mean square error (MMSE) linear precoder are also used in the proposed scheme to detect the presence of interference signals. Numerical results show that the proposed R-STIA technique achieves a better performance in terms of the bit error rate (BER) and sum-rate compared to the existing broadcast channel schemes.

  6. Implementing Strategic Planning Capabilities Within the Mars Relay Operations Service

    NASA Technical Reports Server (NTRS)

    Hy, Franklin; Gladden, Roy; Allard, Dan; Wallick, Michael

    2011-01-01

    Since the Mars Exploration Rovers (MER), Spirit and Opportunity, began their travels across the Martian surface in January of 2004, orbiting spacecraft such as the Mars 2001 Odyssey orbiter have relayed the majority of their collected scientific and operational data to and from Earth. From the beginning of those missions, it was evident that using orbiters to relay data to and from the surface of Mars was a vastly more efficient communications strategy in terms of power consumption and bandwidth compared to direct-to-Earth means. However, the coordination between the various spacecraft, which are largely managed independently and on differing commanding timelines, has always proven to be a challenge. Until recently, the ground operators of all these spacecraft have coordinated the movement of data through this network using a collection of ad hoc human interfaces and various, independent software tools. The Mars Relay Operations Service (MaROS) has been developed to manage the evolving needs of the Mars relay network, and specifically to standardize and integrate the relay planning and coordination data into a centralized infrastructure. This paper explores the journey of developing the MaROS system, from inception to delivery and acceptance by the Mars mission users.

  7. Topological Interference Management for K-User Downlink Massive MIMO Relay Network Channel

    PubMed Central

    Li, Jun; Lee, Moon Ho

    2017-01-01

    In this paper, we study the emergence of topological interference alignment and the characterizing features of a multi-user broadcast interference relay channel. We propose an alternative transmission strategy named the relay space-time interference alignment (R-STIA) technique, in which a K-user multiple-input-multiple-output (MIMO) interference channel has massive antennas at the transmitter and relay. Severe interference from unknown transmitters affects the downlink relay network channel and degrades the system performance. An additional (unintended) receiver is introduced in the proposed R-STIA technique to overcome the above problem, since it has the ability to decode the desired signals for the intended receiver by considering cooperation between the receivers. The additional receiver also helps in recovering and reconstructing the interference signals with limited channel state information at the relay (CSIR). The Alamouti space-time transmission technique and minimum mean square error (MMSE) linear precoder are also used in the proposed scheme to detect the presence of interference signals. Numerical results show that the proposed R-STIA technique achieves a better performance in terms of the bit error rate (BER) and sum-rate compared to the existing broadcast channel schemes. PMID:28817071

  8. RoCoMAR: Robots' Controllable Mobility Aided Routing and Relay Architecture for Mobile Sensor Networks

    PubMed Central

    Van Le, Duc; Oh, Hoon; Yoon, Seokhoon

    2013-01-01

    In a practical deployment, mobile sensor network (MSN) suffers from a low performance due to high node mobility, time-varying wireless channel properties, and obstacles between communicating nodes. In order to tackle the problem of low network performance and provide a desired end-to-end data transfer quality, in this paper we propose a novel ad hoc routing and relaying architecture, namely RoCoMAR (Robots' Controllable Mobility Aided Routing) that uses robotic nodes' controllable mobility. RoCoMAR repeatedly performs link reinforcement process with the objective of maximizing the network throughput, in which the link with the lowest quality on the path is identified and replaced with high quality links by placing a robotic node as a relay at an optimal position. The robotic node resigns as a relay if the objective is achieved or no more gain can be obtained with a new relay. Once placed as a relay, the robotic node performs adaptive link maintenance by adjusting its position according to the movements of regular nodes. The simulation results show that RoCoMAR outperforms existing ad hoc routing protocols for MSN in terms of network throughput and end-to-end delay. PMID:23881134

  9. Le graben de l'Anti-Atlas occidental (Maroc) : contrôle tectonique de la paléogéographie et des séquences au Cambrien inférieurThe Lower-Cambrian western Anti-Atlasic graben: tectonic control of palaeogeography and sequential organisation

    NASA Astrophysics Data System (ADS)

    Benssaou, Mohammed; Hamoumi, Naı̈ma

    2003-03-01

    In the Moroccan western Anti-Atlas, the combined extensive tectonic events with a long-term sea-level rise is the main factor on building vertical stacking transgressive-regressive sequences. In the Ait Abdallah-Boussafene axis, the subsidence processes, relayed by a brutal platform tilting generated an elongated NE-SW graben. This is an evidence of the persistence of the Anti-Atlasic rifting process during the last part of the Lower-Cambrian succession.

  10. A second chance for Solar Max

    NASA Technical Reports Server (NTRS)

    Maran, S. P.; Woodgate, B. E.

    1984-01-01

    Using NASA's Tracking and Data Relay Satellite as a communications link, astronomers are able to receive scans from the Solar Maximum Mission (SMM) satellite immediately and regularly at the Goddard Space Flight Center. This major operational improvement permits the examination of SMM imagery and spectra as they arrive, as well as the formulation of future observational sequences on the basis of the solar activity in progress. Attention is given to aspects of the sun that change in the course of the 11-year sunspot cycle's movement from maximum to minimum. Proof has been obtained by means of SMM for the near-simultaneity of X-ray and UV bursts at flare onset.

  11. A Martian Telecommunications Network: UHF Relay Support of the Mars Exploration Rovers by the Mars Global Surveyor, Mars Odyssey, and Mars Express Orbiters

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D., Jr.; Barbieri, A.; Brower, E.; Estabrook, P.; Gibbs, R.; Horttor, R.; Ludwinski, J.; Mase, R.; McCarthy, C.; Schmidt, R.; hide

    2004-01-01

    NASA and ESA have established an international network of Mars orbiters, outfitted with relay communications payloads, to support robotic exploration of the red planet. Starting in January, 2004, this network has provided the Mars Exploration Rovers with telecommunications relay services, significantly increasing rover engineering and science data return while enhancing mission robustness and operability. Augmenting the data return capabilities of their X-band direct-to-Earth links, the rovers are equipped with UHF transceivers allowing data to be relayed at high rate to the Mars Global Surveyor (MGS), Mars Odyssey, and Mars Express orbiters. As of 21 July, 2004, over 50 Gbits of MER data have been obtained, with nearly 95% of that data returned via the MGS and Odyssey UHF relay paths, allowing a large increase in science return from the Martian surface relative to the X-band direct-to-Earth link. The MGS spacecraft also supported high-rate UHF communications of MER engineering telemetry during the critical period of entry, descent, and landing (EDL), augmenting the very low-rate EDL data collected on the X-band direct-to-Earth link. Through adoption of the new CCSDS Proximity-1 Link Protocol, NASA and ESA have achieved interoperability among these Mars assets, as validated by a successful relay demonstration between Spirit and Mars Express, enabling future interagency cross-support and establishing a truly international relay network at Mars.

  12. 75 FR 79317 - Airworthiness Directives; The Boeing Company Model 737-600, -700, -700C, -800, and -900 Series...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-20

    ... replacement of the power control relays in the P91 and P92 power distribution panels for the fuel boost and override pumps with new, improved relays having a ground fault interrupter (GFI) feature, or installation... specify which relays may be replaced by GFIs or UFIs. We are proposing this AD to prevent pump housing...

  13. Nanoparticle-Wetted Relays: Reconfigurable Surfaces for Energy Transmission Contacts

    DTIC Science & Technology

    2007-01-01

    in-situ monitoring of contact processes as described previously4,17. 9 1. Da Vinci , Leonardo . Madrid Codices, Manuscript I. Biblioteca Nacional...technologists from pre-Hellenistic pulleys and Da Vinci mechanisms for transmission of mechanical energy to modern switches and relays for...Hellenistic pulleys and Da Vinci mechanisms for transmission of mechanical energy1 to modern switches and relays for transmission of electrical energy

  14. Symbol Error Rate of Underlay Cognitive Relay Systems over Rayleigh Fading Channel

    NASA Astrophysics Data System (ADS)

    Ho van, Khuong; Bao, Vo Nguyen Quoc

    Underlay cognitive systems allow secondary users (SUs) to access the licensed band allocated to primary users (PUs) for better spectrum utilization with the power constraint imposed on SUs such that their operation does not harm the normal communication of PUs. This constraint, which limits the coverage range of SUs, can be offset by relaying techniques that take advantage of shorter range communication for lower path loss. Symbol error rate (SER) analysis of underlay cognitive relay systems over fading channel has not been reported in the literature. This paper fills this gap. The derived SER expressions are validated by simulations and show that underlay cognitive relay systems suffer a high error floor for any modulation level.

  15. Electrical safety device

    DOEpatents

    White, David B.

    1991-01-01

    An electrical safety device for use in power tools that is designed to automatically discontinue operation of the power tool upon physical contact of the tool with a concealed conductive material. A step down transformer is used to supply the operating power for a disconnect relay and a reset relay. When physical contact is made between the power tool and the conductive material, an electrical circuit through the disconnect relay is completed and the operation of the power tool is automatically interrupted. Once the contact between the tool and conductive material is broken, the power tool can be quickly and easily reactivated by a reset push button activating the reset relay. A remote reset is provided for convenience and efficiency of operation.

  16. Use of amplicon sequencing to improve sensitivity in PCR-based detection of microbial pathogen in environmental samples.

    PubMed

    Saingam, Prakit; Li, Bo; Yan, Tao

    2018-06-01

    DNA-based molecular detection of microbial pathogens in complex environments is still plagued by sensitivity, specificity and robustness issues. We propose to address these issues by viewing them as inadvertent consequences of requiring specific and adequate amplification (SAA) of target DNA molecules by current PCR methods. Using the invA gene of Salmonella as the model system, we investigated if next generation sequencing (NGS) can be used to directly detect target sequences in false-negative PCR reaction (PCR-NGS) in order to remove the SAA requirement from PCR. False-negative PCR and qPCR reactions were first created using serial dilutions of laboratory-prepared Salmonella genomic DNA and then analyzed directly by NGS. Target invA sequences were detected in all false-negative PCR and qPCR reactions, which lowered the method detection limits near the theoretical minimum of single gene copy detection. The capability of the PCR-NGS approach in correcting false negativity was further tested and confirmed under more environmentally relevant conditions using Salmonella-spiked stream water and sediment samples. Finally, the PCR-NGS approach was applied to ten urban stream water samples and detected invA sequences in eight samples that would be otherwise deemed Salmonella negative. Analysis of the non-target sequences in the false-negative reactions helped to identify primer dime-like short sequences as the main cause of the false negativity. Together, the results demonstrated that the PCR-NGS approach can significantly improve method sensitivity, correct false-negative detections, and enable sequence-based analysis for failure diagnostics in complex environmental samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Joint terminals and relay optimization for two-way power line information exchange systems with QoS constraints

    NASA Astrophysics Data System (ADS)

    Wu, Xiaolin; Rong, Yue

    2015-12-01

    The quality-of-service (QoS) criteria (measured in terms of the minimum capacity requirement in this paper) are very important to practical indoor power line communication (PLC) applications as they greatly affect the user experience. With a two-way multicarrier relay configuration, in this paper we investigate the joint terminals and relay power optimization for the indoor broadband PLC environment, where the relay node works in the amplify-and-forward (AF) mode. As the QoS-constrained power allocation problem is highly non-convex, the globally optimal solution is computationally intractable to obtain. To overcome this challenge, we propose an alternating optimization (AO) method to decompose this problem into three convex/quasi-convex sub-problems. Simulation results demonstrate the fast convergence of the proposed algorithm under practical PLC channel conditions. Compared with the conventional bidirectional direct transmission (BDT) system, the relay-assisted two-way information exchange (R2WX) scheme can meet the same QoS requirement with less total power consumption.

  18. Enantio-Relay Catalysis Constructs Chiral Biaryl Alcohols over Cascade Suzuki Cross-Coupling-Asymmetric Transfer Hydrogenation

    NASA Astrophysics Data System (ADS)

    Zhang, Dacheng; Gao, Xiaoshuang; Cheng, Tanyu; Liu, Guohua

    2014-05-01

    The construction of chiral biaryl alcohols using enantio-relay catalysis is a particularly attractive synthetic method in organic synthesis. However, overcoming the intrinsic incompatibility of distinct organometallic complexes and the reaction conditions used are significant challenges in asymmetric catalysis. To overcome these barriers, we have taken advantage of an enantio-relay catalysis strategy and a combined dual-immobilization approach. We report the use of an imidazolium-based organopalladium-functionalized organic-inorganic hybrid silica and ethylene-coated chiral organoruthenium-functionalized magnetic nanoparticles to catalyze a cascade Suzuki cross-coupling-asymmetric transfer hydrogenation reaction to prepare chiral biaryl alcohols in a two-step, one-pot process. As expected, the site-isolated active species, salient imidazolium phase-transfer character and high ethylene-coated hydrophobicity can synergistically boost the catalytic performance. Furthermore, enantio-relay catalysis has the potential to efficiently prepare a variety of chiral biaryl alcohols. Our synthetic strategy is a general method that shows the potential of developing enantio-relay catalysis towards environmentally benign and sustainable organic synthesis.

  19. [Testing system design and analysis for the execution units of anti-thrombotic device].

    PubMed

    Li, Zhelong; Cui, Haipo; Shang, Kun; Liao, Yuehua; Zhou, Xun

    2015-02-01

    In an anti-thrombotic pressure circulatory device, relays and solenoid valves serve as core execution units. Thus the therapeutic efficacy and patient safety of the device will directly depend on their performance. A new type of testing system for relays and solenoid valves used in the anti-thrombotic device has been developed, which can test action response time and fatigue performance of relay and solenoid valve. PC, data acquisition card and test platform are used in this testing system based on human-computer interaction testing modules. The testing objectives are realized by using the virtual instrument technology, the high-speed data acquisition technology and reasonable software design. The two sets of the system made by relay and solenoid valve are tested. The results proved the universality and reliability of the testing system so that these relays and solenoid valves could be accurately used in the antithrombotic pressure circulatory equipment. The newly-developed testing system has a bright future in the aspects of promotion and application prospect.

  20. Scheduler software for tracking and data relay satellite system loading analysis: User manual and programmer guide

    NASA Technical Reports Server (NTRS)

    Craft, R.; Dunn, C.; Mccord, J.; Simeone, L.

    1980-01-01

    A user guide and programmer documentation is provided for a system of PRIME 400 minicomputer programs. The system was designed to support loading analyses on the Tracking Data Relay Satellite System (TDRSS). The system is a scheduler for various types of data relays (including tape recorder dumps and real time relays) from orbiting payloads to the TDRSS. Several model options are available to statistically generate data relay requirements. TDRSS time lines (representing resources available for scheduling) and payload/TDRSS acquisition and loss of sight time lines are input to the scheduler from disk. Tabulated output from the interactive system includes a summary of the scheduler activities over time intervals specified by the user and overall summary of scheduler input and output information. A history file, which records every event generated by the scheduler, is written to disk to allow further scheduling on remaining resources and to provide data for graphic displays or additional statistical analysis.

  1. Performance Analysis of an Inter-Relay Co-operation in FSO Communication System

    NASA Astrophysics Data System (ADS)

    Khanna, Himanshu; Aggarwal, Mona; Ahuja, Swaran

    2018-04-01

    In this work, we analyze the outage and error performance of a one-way inter-relay assisted free space optical link. The assumption of the absence of direct link between the source and destination node is being made for the analysis, and the feasibility of such system configuration is studied. We consider the influence of path loss, atmospheric turbulence and pointing error impairments, and investigate the effect of these parameters on the system performance. The turbulence-induced fading is modeled by independent but not necessarily identically distributed gamma-gamma fading statistics. The closed-form expressions for outage probability and probability of error are derived and illustrated by numerical plots. It is concluded that the absence of line of sight path between source and destination nodes does not lead to significant performance degradation. Moreover, for the system model under consideration, interconnected relaying provides better error performance than the non-interconnected relaying and dual-hop serial relaying techniques.

  2. Application of Advanced Wide Area Early Warning Systems with Adaptive Protection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blumstein, Carl; Cibulka, Lloyd; Thorp, James

    2014-09-30

    Recent blackouts of power systems in North America and throughout the world have shown how critical a reliable power system is to modern societies, and the enormous economic and societal damage a blackout can cause. It has been noted that unanticipated operation of protection systems can contribute to cascading phenomena and, ultimately, blackouts. This project developed and field-tested two methods of Adaptive Protection systems utilizing synchrophasor data. One method detects conditions of system stress that can lead to unintended relay operation, and initiates a supervisory signal to modify relay response in real time to avoid false trips. The second methodmore » detects the possibility of false trips of impedance relays as stable system swings “encroach” on the relays’ impedance zones, and produces an early warning so that relay engineers can re-evaluate relay settings. In addition, real-time synchrophasor data produced by this project was used to develop advanced visualization techniques for display of synchrophasor data to utility operators and engineers.« less

  3. The Role of Remotely Sensed and Relayed Data in the Delaware River Basin

    NASA Technical Reports Server (NTRS)

    Paulson, R. W.

    1971-01-01

    The planned integration of the existing water quality monitoring and data processing systems in the Delaware River Basin with a data relay experiment proposed for the ERTS-1 is discussed. The experiment is designed to use ERTS-1 as a data relay link for a maximum of 20 hydrologic stations in the basin, including stream gaging, reservoir level, ground water level, and water quality monitoring stations. This experiment has the potential for reducing the time lag between data collection and dissemination to less than 12 hours. The experiment will also provide impetus to develop an operational system of real time data processing and dissemination to handle the large quantity of data that will be obtained from the stations in the basin. The results of this experiment will demonstrate the relative merits of satellite relay of data versus conventional means of data telemetry and will provide a basis for the development of operational satellite relay of hydrologic data.

  4. Persistence border collisions in a vibrating system excited by an unbalanced motor with a relay control

    NASA Astrophysics Data System (ADS)

    Zhusubaliyev, Zhanybai T.; Avrutin, Viktor; Rubanov, Vasily G.; Bushuev, Dmitry A.; Titov, Dmitry V.; Yanochkina, Olga O.

    2018-05-01

    The paper describes a new scenario for the transition to complex dynamics in a vibrating system with an unbalanced rotor and a relay feedback control. We show that the transition from a regular dynamics without switching events in the relay element to an irregular dynamics which takes place completely in the hysteresis region occurs via a cascade of persistence border collisions.

  5. Commercialization and Standardization Progress Towards an Optical Communications Earth Relay

    NASA Technical Reports Server (NTRS)

    Edwards, Bernard L.; Israel, David J.

    2015-01-01

    NASA is planning to launch the next generation of a space based Earth relay in 2025 to join the current Space Network, consisting of Tracking and Data Relay Satellites in space and the corresponding infrastructure on Earth. While the requirements and architecture for that relay satellite are unknown at this time, NASA is investing in communications technologies that could be deployed to provide new communications services. One of those new technologies is optical communications. The Laser Communications Relay Demonstration (LCRD) project, scheduled for launch in 2018 as a hosted payload on a commercial communications satellite, is a critical pathfinder towards NASA providing optical communications services on the next generation space based relay. This paper will describe NASA efforts in the on-going commercialization of optical communications and the development of inter-operability standards. Both are seen as critical to making optical communications a reality on future NASA science and exploration missions. Commercialization is important because NASA would like to eventually be able to simply purchase an entire optical communications terminal from a commercial provider. Inter-operability standards are needed to ensure that optical communications terminals developed by one vendor are compatible with the terminals of another. International standards in optical communications would also allow the space missions of one nation to use the infrastructure of another.

  6. Cost and Performance Comparison of an Earth-Orbiting Optical Communication Relay Transceiver and a Ground-Based Optical Receiver Subnet

    NASA Technical Reports Server (NTRS)

    Wilson, K. E.; Wright, M.; Cesarone, R.; Ceniceros, J.; Shea, K.

    2003-01-01

    Optical communications can provide high-data-rate telemetry from deep-space probes with subsystems that have lower mass, consume less power, and are smaller than their radio frequency (RF) counterparts. However, because optical communication is more a.ected by weather than is RF communication, it requires groundstation site diversity to mitigate the adverse e.ects of inclement weather on the link. An optical relay satellite is not a.ected by weather and can provide 24-hour coverage of deep-space probes. Using such a relay satellite for the deep-space link and an 8.4-GHz (X-band) link to a ground station would support high-data-rate links from small deep-space probes with very little link loss due to inclement weather. We have reviewed past JPL-funded work on RF and optical relay satellites, and on proposed clustered and linearly dispersed optical subnets. Cost comparisons show that the life cycle costs of a 7-m optical relay station based on the heritage of the Next Generation Space Telescope is comparable to that of an 8-station subnet of 10- m optical ground stations. This makes the relay link an attractive option vis- a-vis a ground-station network.

  7. COMPASS Final Report: Lunar Relay Satellite (LRS)

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; McGuire, Melissa L.

    2012-01-01

    The Lunar Relay Satellite (LRS) COllaborative Modeling and Parametric Assessment of Space Systems (COMPASS) session was tasked to design a satellite to orbit in an elliptical lunar polar orbit to provide relay communications between lunar South Pole assets and the Earth. The design included a complete master equipment list, power requirement list, configuration design, and brief risk assessment and cost analysis. The LRS is a half-TDRSS sized box spacecraft, which provides communications and navigation relay between lunar outposts (via Lunar Communications Terminals (LCT)) or Sortie parties (with user radios) and large ground antennas on Earth. The LRS consists of a spacecraft containing all the communications and avionics equipment designed by NASA Jet Propulsion Laboratory s (JPL) Team X to perform the relay between lunar-based assets and the Earth. The satellite design is a standard box truss spacecraft design with a thermal control system, 1.7 m solar arrays for 1 kWe power, a 1 m diameter Ka/S band dish which provides relay communications with the LCT, and a Q-band dish for communications to/from the Earth based assets. While JPL's Team X and Goddard Space Flight Center s (GSFC) I M Design Center (IMDC) have completed two other LRS designs, this NASA Glenn Research Center (GRC) COMPASS LRS design sits between them in terms of physical size and capabilities.

  8. Transmission line relay mis-operation detection based on time-synchronized field data

    DOE PAGES

    Esmaeilian, Ahad; Popovic, Tomo; Kezunovic, Mladen

    2015-05-04

    In this paper, a real-time tool to detect transmission line relay mis-operation is implemented. The tool uses time-synchronized measurements obtained from both ends of the line during disturbances. The proposed fault analysis tool comes into the picture only after the protective device has operated and tripped the line. The proposed methodology is able not only to detect, classify, and locate transmission line faults, but also to accurately confirm whether the line was tripped due to a mis-operation of protective relays. The analysis report includes either detailed description of the fault type and location or detection of relay mis-operation. As such,more » it can be a source of very useful information to support the system restoration. The focus of the paper is on the implementation requirements that allow practical application of the methodology, which is illustrated using the field data obtained the real power system. Testing and validation is done using the field data recorded by digital fault recorders and protective relays. The test data included several hundreds of event records corresponding to both relay mis-operations and actual faults. The discussion of results addresses various challenges encountered during the implementation and validation of the presented methodology.« less

  9. Cost and Performance Comparison of an Earth-Orbiting Optical Communication Relay Transceiver and a Ground-Based Optical Receiver Subnet

    NASA Astrophysics Data System (ADS)

    Wilson, K. E.; Wright, M.; Cesarone, R.; Ceniceros, J.; Shea, K.

    2003-01-01

    Optical communications can provide high-data-rate telemetry from deep-space probes with subsystems that have lower mass, consume less power, and are smaller than their radio frequency (RF) counterparts. However, because optical communication is more affected by weather than is RF communication, it requires ground station site diversity to mitigate the adverse effects of inclement weather on the link. An optical relay satellite is not affected by weather and can provide 24-hour coverage of deep-space probes. Using such a relay satellite for the deep-space link and an 8.4-GHz (X-band) link to a ground station would support high-data-rate links from small deep-space probes with very little link loss due to inclement weather. We have reviewed past JPL-funded work on RF and optical relay satellites, and on proposed clustered and linearly dispersed optical subnets. Cost comparisons show that the life cycle costs of a 7-m optical relay station based on the heritage of the Next Generation Space Telescope is comparable to that of an 8-station subnet of 10-m optical ground stations. This makes the relay link an attractive option vis-a-vis a ground station network.

  10. Growth and physiological changes in continuously cropped eggplant (Solanum melongena L.) upon relay intercropping with garlic (Allium sativum L.)

    PubMed Central

    Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen

    2015-01-01

    Relay intercropping represents an alternative for sustainable production of vegetables, but the changes of internally antioxidant defense combined with the growth and yield are not clear. Field experiment was carried out to investigate the malondialdehyde (MDA) content and activity levels of superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) in eggplant (Solanum melongena L.) and plant height, stem diameter, maximal leaf area, and yield of eggplant grown under successive cropping in the year 2011 and 2012 to see if relay intercropping with garlic (Allium sativum L.) could benefit to eggplant growth and yield. Three experimental treatments with three repeats in each were carried out (completely randomized block design): eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG), and eggplant relay intercropping with green garlic (GG). In both years, the MDA content was significantly lower and SOD and POD activities were generally lower in NG and GG compared with CK in most sampling dates. PPO activity trends were generally opposite to those of POD. The general trend of PAL activity was similar to MDA. The plant height and stem of eggplant was lower, but the maximal leaf area was larger in NG and GG in 2011; in 2012 the plant growth was stronger in relay intercropping treatments. For eggplant yield in 2011, NG was 2.85% higher than CK; after the time for the green garlic pulled out was moved forward in 2012, the yield was increased by 6.26 and 7.80%, respectively, in NG and GG. The lower MDA content and enzyme activities in relay intercropping treatments showed that the eggplant suffered less damage from environment and continuous cropping obstacles, which promoted healthier plant. Thus from both the growth and physiological perspective, it was concluded that eggplant/garlic relay intercropping is a beneficial cultivation practice maintaining stronger plant growth and higher yield. PMID:25964788

  11. Growth and physiological changes in continuously cropped eggplant (Solanum melongena L.) upon relay intercropping with garlic (Allium sativum L.).

    PubMed

    Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen

    2015-01-01

    Relay intercropping represents an alternative for sustainable production of vegetables, but the changes of internally antioxidant defense combined with the growth and yield are not clear. Field experiment was carried out to investigate the malondialdehyde (MDA) content and activity levels of superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) in eggplant (Solanum melongena L.) and plant height, stem diameter, maximal leaf area, and yield of eggplant grown under successive cropping in the year 2011 and 2012 to see if relay intercropping with garlic (Allium sativum L.) could benefit to eggplant growth and yield. Three experimental treatments with three repeats in each were carried out (completely randomized block design): eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG), and eggplant relay intercropping with green garlic (GG). In both years, the MDA content was significantly lower and SOD and POD activities were generally lower in NG and GG compared with CK in most sampling dates. PPO activity trends were generally opposite to those of POD. The general trend of PAL activity was similar to MDA. The plant height and stem of eggplant was lower, but the maximal leaf area was larger in NG and GG in 2011; in 2012 the plant growth was stronger in relay intercropping treatments. For eggplant yield in 2011, NG was 2.85% higher than CK; after the time for the green garlic pulled out was moved forward in 2012, the yield was increased by 6.26 and 7.80%, respectively, in NG and GG. The lower MDA content and enzyme activities in relay intercropping treatments showed that the eggplant suffered less damage from environment and continuous cropping obstacles, which promoted healthier plant. Thus from both the growth and physiological perspective, it was concluded that eggplant/garlic relay intercropping is a beneficial cultivation practice maintaining stronger plant growth and higher yield.

  12. Late Cenozoic extensional faulting in Central-Western Peloponnesus, Greece

    NASA Astrophysics Data System (ADS)

    Skourtsos, E.; Fountoulis, I.; Mavroulis, S.; Kranis, H.

    2012-04-01

    A series of forearc-dipping, orogen-parallel extensional faults are found in the central-western Peloponnesus, (south-western Aegean) which control the western margin of Mt Mainalon. The latter comprises HP/LT rocks of the Phyllites-Quartzites Unit (PQ), overlain by the carbonates and flysch of the Tripolis Unit while the uppermost nappe is the Pindos Unit, a sequence of Mesozoic pelagic sequence, topped by a Paleocene flysch. Most of the extensional structures were previously thought of as the original thrust between the Pindos and Tripolis Units. However, the cross-cutting relationships among these structures indicate that these are forearc (SW-dipping) extensional faults, downthrowing the Pindos thrust by a few tens or hundreds of meters each, rooting onto different levels of the nappe pile. In SW Mainalon the lowermost of the extensional faults is a low-angle normal fault dipping SW juxtaposing the metamorphic rocks of the PQ Unit against the non-metamorphic sequence of the Tripolis Unit. High-angle normal faults, found further to the west, have truncated or even sole onto the low-angle ones and control the eastern margin of the Quaternary Megalopolis basin. All these extensional structures form the eastern boundary of a series of Neogene-Quaternary tectonic depressions, which in turn are separated by E-W horsts. In the NW, these faults are truncated by NE to NNE-striking, NW-dipping faults, which relay the whole fault activity to the eastern margin of the Pyrgos graben. The whole extensional fault architecture has resulted (i) in the Pindos thrust stepping down from altitudes higher than 1000 m in Mainalon in the east, to negative heights in North Messinia and Southern Ilia in the west; and (ii) the gradual disappearance of the Phyllite-Quartzite metamorphics of Mainalon towards the west. The combination of these extensional faults (which may reach down to the Ionian décollement) with the low-angle floor thrusts of the Pindos, Tripolis and Ionian Units leads to additional ENE-WSW shortening, normal to the Hellenic Arc, west of the Peloponnesus.

  13. Representing Network Trust and Using It to Improve Anonymous Communication

    DTIC Science & Technology

    2014-07-01

    identified by that behavior . References 1. Augustin, B., Krishnamurthy, B., Willinger, W.: IXPs: Mapped? In: Internet Mea- surement Conference ( IMC ’09...empty attributes (e.g., labeling countries by their larger geographic region). The user’s beliefs may incorporate boolean predicates that are evaluated on...and behaviors are. The most useful information about Tor relays for setting a default level of trust is probably relay longevity. Running a relay in

  14. Joint Transmit Antenna Selection and Power Allocation for ISDF Relaying Mobile-to-Mobile Sensor Networks

    PubMed Central

    Xu, Lingwei; Zhang, Hao; Gulliver, T. Aaron

    2016-01-01

    The outage probability (OP) performance of multiple-relay incremental-selective decode-and-forward (ISDF) relaying mobile-to-mobile (M2M) sensor networks with transmit antenna selection (TAS) over N-Nakagami fading channels is investigated. Exact closed-form OP expressions for both optimal and suboptimal TAS schemes are derived. The power allocation problem is formulated to determine the optimal division of transmit power between the broadcast and relay phases. The OP performance under different conditions is evaluated via numerical simulation to verify the analysis. These results show that the optimal TAS scheme has better OP performance than the suboptimal scheme. Further, the power allocation parameter has a significant influence on the OP performance. PMID:26907282

  15. Fully relayed regenerative amplifier

    DOEpatents

    Glass, Alexander J.

    1981-01-01

    A regenerative laser apparatus and method using the optical relay concept to maintain high fill factors, to suppress diffraction effects, and to minimize phase distortions in a regenerative amplifier.

  16. Identification of the bacterial etiology of culture-negative endocarditis by amplification and sequencing of a small ribosomal RNA gene.

    PubMed

    Khulordava, Irakli; Miller, Geraldine; Haas, David; Li, Haijing; McKinsey, Joel; Vanderende, Daniel; Tang, Yi-Wei

    2003-05-01

    We report two cases of culture-negative bacterial endocarditis in which the organisms were identified by amplification and sequencing of the bacterial 16S rRNA gene. These results support an important role for polymerase chain reaction followed by direct sequencing to determine the etiology of culture-negative bacterial endocarditis and to guide appropriate antimicrobial therapy.

  17. Data Relay Board with Protocol for High-Speed, Free-Space Optical Communications

    NASA Technical Reports Server (NTRS)

    Wright, Malcolm; Clare, Loren; Gould, Gary; Pedyash, Maxim

    2004-01-01

    In a free-space optical communication system, the mitigation of transient outages through the incorporation of error-control methods is of particular concern, the outages being caused by scintillation fades and obscurants. The focus of this innovative technology is the development of a data relay system for a reliable high-data-rate free-spacebased optical-transport network. The data relay boards will establish the link, maintain synchronous connection, group the data into frames, and provide for automatic retransmission (ARQ) of lost or erred frames. A certain Quality of Service (QoS) can then be ensured, compatible with the required data rate. The protocol to be used by the data relay system is based on the draft CCSDS standard data-link protocol Proximity-1, selected by orbiters to multiple lander assets in the Mars network, for example. In addition to providing data-link protocol capabilities for the free-space optical link and buffering the data, the data relay system will interface directly with user applications over Gigabit Ethernet and/or with highspeed storage resources via Fibre Channel. The hardware implementation is built on a network-processor-based architecture. This technology combines the power of a hardware switch capable of data switching and packet routing at Gbps rates, with the flexibility of a software- driven processor that can host highly adaptive and reconfigurable protocols used, for example, in wireless local-area networks (LANs). The system will be implemented in a modular multi-board fashion. The main hardware elements of the data relay system are the new data relay board developed by Rockwell Scientific, a COTS Gigabit Ethernet board for user interface, and a COTS Fibre Channel board that connects to local storage. The boards reside in a cPCI back plane, and can be housed in a VME-type enclosure.

  18. On Proper Selection of Multihop Relays for Future Enhancement of AeroMACS Networks

    NASA Technical Reports Server (NTRS)

    Kamali, Behnam; Kerczewski, Robert J.; Apaza, Rafael D.

    2015-01-01

    As the Aeronautical Mobile Airport Communications System (AeroMACS) has evolved from a technology concept to a deployed communications network over major US airports, it is now time to contemplate whether the existing capacity of AeroMACS is sufficient to meet the demands set forth by all fixed and mobile applications over the airport surface given the AeroMACS constraints regarding bandwidth and transmit power. The underlying idea in this article is to present IEEE 802.16j-based WiMAX as a technology that can address future capacity enhancements and therefore is most feasible for AeroMACS applications. The principal argument in favor IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified networks, with virtually no increase in the power requirements and virtually no rise in interference levels to co-allocated applications. The IEEE 802.16j-based multihop relay systems are briefly described. The focus is on key features of this technology, frame structure, and its architecture. Next, AeroMACS is described as a WiMAX-based wireless network. The two major relay modes supported by IEEE 802.16j amendment, i.e., transparent and non-transparent are described. The benefits of employing multihop relays are listed. Some key challenges related to incorporating relays into AeroMACS networks are discussed. The selection of relay type in a broadband wireless network affects a number of network parameters such as latency, signal overhead, PHY (Scalable Physical Layer) and MAC (Media Access Layer) layer protocols, consequently it can alter key network quantities of throughput and QoS (Quality of Service).

  19. Tracking and Data Relay Satellite System user impact and network compatibility study. [antenna design and telecommunication links

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The report contains data on antenna configurations for the low data rate users of the Tracking and Data Relay Satellite System (TDRSS). It treats the coverage and mutual visibility considerations between the user satellites and the relay satellites and relates these considerations to requirements of antenna beamwidth and fractional user orbital coverage. A final section includes user/TDRS telecommunication link budgets and forward and return link data rate tradeoffs.

  20. Relay-based information broadcast in complex networks

    NASA Astrophysics Data System (ADS)

    Fan, Zhongyan; Han, Zeyu; Tang, Wallace K. S.; Lin, Dong

    2018-04-01

    Information broadcast (IB) is a critical process in complex network, usually accomplished by flooding mechanism. Although flooding is simple and no prior topological information is required, it consumes a lot of transmission overhead. Another extreme is the tree-based broadcast (TB), for which information is disseminated via a spanning tree. It achieves the minimal transmission overhead but the maintenance of spanning tree for every node is an obvious obstacle for implementation. Motivated by the success of scale-free network models for real-world networks, in this paper, we investigate the issues in IB by considering an alternative solution in-between these two extremes. A novel relay-based broadcast (RB) mechanism is proposed by employing a subset of nodes as relays. Information is firstly forwarded to one of these relays and then re-disseminated to others through the spanning tree whose root is the relay. This mechanism provides a trade-off solution between flooding and TB. On one hand, it saves up a lot of transmission overhead as compared to flooding; on the other hand, it costs much less resource for maintenance than TB as only a few spanning trees are needed. Based on two major criteria, namely the transmission overhead and the convergence time, the effectiveness of RB is confirmed. The impacts of relay assignment and network structures on performance are also studied in this work.

  1. Experiment definition phase shuttle laboratory LDRL-10.6 experiment. [applying optical communication

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The 10.6 microns laser data relay link (LDRL 10.6) program was directed to applying optical communications to NASA's wideband data transmission requirements through the 1980's. The LDRL consists of a transmitter on one or more low earth orbit satellites with an elliptical orbit satellite receivers. Topics discussed include: update of the LDRL design control table to detail the transmitter optical chain losses and to incorporate the change to a reflective beam pre-expander; continued examination of the link establishment sequence, including its dependence upon spacecraft stability; design of the transmitter pointing and tracking control system; and finalization of the transmitter brassboard optical and mechanical design.

  2. Network command processing system overview

    NASA Technical Reports Server (NTRS)

    Nam, Yon-Woo; Murphy, Lisa D.

    1993-01-01

    The Network Command Processing System (NCPS) developed for the National Aeronautics and Space Administration (NASA) Ground Network (GN) stations is a spacecraft command system utilizing a MULTIBUS I/68030 microprocessor. This system was developed and implemented at ground stations worldwide to provide a Project Operations Control Center (POCC) with command capability for support of spacecraft operations such as the LANDSAT, Shuttle, Tracking and Data Relay Satellite, and Nimbus-7. The NCPS consolidates multiple modulation schemes for supporting various manned/unmanned orbital platforms. The NCPS interacts with the POCC and a local operator to process configuration requests, generate modulated uplink sequences, and inform users of the ground command link status. This paper presents the system functional description, hardware description, and the software design.

  3. Performance Analysis of Physical Layer Security of Opportunistic Scheduling in Multiuser Multirelay Cooperative Networks

    PubMed Central

    Shim, Kyusung; Do, Nhu Tri; An, Beongku

    2017-01-01

    In this paper, we study the physical layer security (PLS) of opportunistic scheduling for uplink scenarios of multiuser multirelay cooperative networks. To this end, we propose a low-complexity, yet comparable secrecy performance source relay selection scheme, called the proposed source relay selection (PSRS) scheme. Specifically, the PSRS scheme first selects the least vulnerable source and then selects the relay that maximizes the system secrecy capacity for the given selected source. Additionally, the maximal ratio combining (MRC) technique and the selection combining (SC) technique are considered at the eavesdropper, respectively. Investigating the system performance in terms of secrecy outage probability (SOP), closed-form expressions of the SOP are derived. The developed analysis is corroborated through Monte Carlo simulation. Numerical results show that the PSRS scheme significantly improves the secure ability of the system compared to that of the random source relay selection scheme, but does not outperform the optimal joint source relay selection (OJSRS) scheme. However, the PSRS scheme drastically reduces the required amount of channel state information (CSI) estimations compared to that required by the OJSRS scheme, specially in dense cooperative networks. PMID:28212286

  4. Performance Analysis of Amplify-and-Forward Relaying FSO/SC-QAM Systems over Weak Turbulence Channels and Pointing Error Impairments

    NASA Astrophysics Data System (ADS)

    Trung, Ha Duyen

    2017-12-01

    In this paper, the end-to-end performance of free-space optical (FSO) communication system combining with Amplify-and-Forward (AF)-assisted or fixed-gain relaying technology using subcarrier quadrature amplitude modulation (SC-QAM) over weak atmospheric turbulence channels modeled by log-normal distribution with pointing error impairments is studied. More specifically, unlike previous studies on AF relaying FSO communication systems without pointing error effects; the pointing error effect is studied by taking into account the influence of beamwidth, aperture size and jitter variance. In addition, a combination of these models to analyze the combined effect of atmospheric turbulence and pointing error to AF relaying FSO/SC-QAM systems is used. Finally, an analytical expression is derived to evaluate the average symbol error rate (ASER) performance of such systems. The numerical results show that the impact of pointing error on the performance of AF relaying FSO/SC-QAM systems and how we use proper values of aperture size and beamwidth to improve the performance of such systems. Some analytical results are confirmed by Monte-Carlo simulations.

  5. 47 CFR 74.436 - Special requirements for automatic relay stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

  6. 47 CFR 74.436 - Special requirements for automatic relay stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

  7. 47 CFR 74.436 - Special requirements for automatic relay stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

  8. 47 CFR 74.436 - Special requirements for automatic relay stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

  9. 47 CFR 74.436 - Special requirements for automatic relay stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

  10. KSC-2013-4396

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at Cape Canaveral Air Force Station's Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  11. KSC-2013-4394

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at Cape Canaveral Air Force Station's Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  12. KSC-2013-4428

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, a Centaur second stage is positioned atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  13. KSC-2013-3790

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur upper stage that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  14. KSC-2013-4395

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at Cape Canaveral Air Force Station's Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  15. KSC-2013-3792

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur upper stage that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  16. KSC-2013-4429

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, a Centaur second stage is positioned atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  17. Spaceborne CO2 laser communications systems

    NASA Technical Reports Server (NTRS)

    Mcelroy, J. H.; Mcavoy, N.; Johnson, E. H.; Goodwin, F. E.; Peyton, B. J.

    1975-01-01

    Projections of the growth of earth-sensing systems for the latter half of the 1980's show a data transmission requirement of 300 Mbps and above. Mission constraints and objectives lead to the conclusion that the most efficient technique to return the data from the sensing satellite to a ground station is through a geosynchronous data relay satellite. Of the two links that are involved (sensing satellite to relay satellite and relay satellite to ground), a laser system is most attractive for the space-to-space link. The development of CO2 laser systems for space-to-space applications is discussed with the completion of a 300 Mpbs data relay receiver and its modification into a transceiver. The technology and state-of-the-art of such systems are described in detail.

  18. Satellite Relaying of Geophysical Data

    NASA Technical Reports Server (NTRS)

    Allenby, R. J.

    1977-01-01

    Data Collection Platforms (DCPs) for transmitting surface data to an orbiting satellite for relaying to a central data distribution center are being used in a number of geophysical applications. "Off-the-shelf" DCP's, transmitting through Landsat or GOES satellites, are fully capable of relaying data from low-data-rate instruments, such as tiltmeters or tide gauges. In cooperation with the Lamont-Doherty Geological Observatory, Goddard has successfully installed DCP systems on a tide gauge and tiltmeter array on Anegada, British Virgin Islands. Because of the high-data-rate requirements, a practical relay system capable of handling seismic information is not yet available. Such a system could become the basis of an operational hazard prediction system for reducing losses due to major natural catastrophies such as earthquakes, volcanic eruptions, landslides or tsunamis.

  19. Multistability and hidden attractors in a relay system with hysteresis

    NASA Astrophysics Data System (ADS)

    Zhusubaliyev, Zhanybai T.; Mosekilde, Erik; Rubanov, Vasily G.; Nabokov, Roman A.

    2015-06-01

    For nonlinear dynamic systems with switching control, the concept of a "hidden attractor" naturally applies to a stable dynamic state that either (1) coexists with the stable switching cycle or (2), if the switching cycle is unstable, has a basin of attraction that does not intersect with the neighborhood of that cycle. We show how the equilibrium point of a relay system disappears in a boundary-equilibrium bifurcation as the system enters the region of autonomous switching dynamics and demonstrate experimentally how a relay system can exhibit large amplitude chaotic oscillations at high values of the supply voltage. By investigating a four-dimensional model of the experimental relay system we finally show how a variety of hidden periodic, quasiperiodic and chaotic attractors arise, transform and disappear through different bifurcations.

  20. Measurement-Device-Independent Quantum Key Distribution over Untrustful Metropolitan Network

    NASA Astrophysics Data System (ADS)

    Tang, Yan-Lin; Yin, Hua-Lei; Zhao, Qi; Liu, Hui; Sun, Xiang-Xiang; Huang, Ming-Qi; Zhang, Wei-Jun; Chen, Si-Jing; Zhang, Lu; You, Li-Xing; Wang, Zhen; Liu, Yang; Lu, Chao-Yang; Jiang, Xiao; Ma, Xiongfeng; Zhang, Qiang; Chen, Teng-Yun; Pan, Jian-Wei

    2016-01-01

    Quantum cryptography holds the promise to establish an information-theoretically secure global network. All field tests of metropolitan-scale quantum networks to date are based on trusted relays. The security critically relies on the accountability of the trusted relays, which will break down if the relay is dishonest or compromised. Here, we construct a measurement-device-independent quantum key distribution (MDIQKD) network in a star topology over a 200-square-kilometer metropolitan area, which is secure against untrustful relays and against all detection attacks. In the field test, our system continuously runs through one week with a secure key rate 10 times larger than previous results. Our results demonstrate that the MDIQKD network, combining the best of both worlds—security and practicality, constitutes an appealing solution to secure metropolitan communications.

  1. Selective heteronuclear Hartmann-Hahn: A multiple-pulse sequence for selective magnetization transfer in the structural elucidation of “isotagged” oligosaccharides

    NASA Astrophysics Data System (ADS)

    Meng, Xi; Nguyen, William H.; Nowick, James S.; Shaka, A. J.

    2010-03-01

    A new selective heteronuclear Hartmann-Hahn (SHEHAHA) multiple-pulse mixing sequence is proposed for the solution structure elucidation of milligram amounts of peracetylated oligosaccharides in which the acetyl groups are enriched in carbon-13, so-called “isotags”. SHEHAHA accomplishes exclusive in-phase magnetization transfer between the isotag carbonyl 13C and the proximal proton on the sugar ring. Relayed transfer around the sugar rings by proton-proton TOCSY is suppressed, while the heteronuclear transfer from the labeled carbonyl carbon to the proximal ring proton is maintained. The sequence is broadband in the sense that all acetyl groups simultaneously give good signal transfer to their respective nearest proton neighbors. The 1H-detected spectra have decent sensitivity and excellent resolution, giving patterns that unambiguously identify common structural subunits in human glycans. Peracetylated maltitol is shown as a test case of the method. Lineshapes are pure absorption, allowing facile measurement of vicinal proton-proton couplings. Linkage points can be deduced, and the 2D correlation spectra may be useful for more ambitious prediction algorithms and machine identification by a spectral database.

  2. Reading the tea leaves: Dead transposon copies reveal novel host and transposon biology.

    PubMed

    McLaughlin, Richard N

    2018-03-01

    Transposable elements comprise a huge portion of most animal genomes. Unlike many pathogens, these elements leave a mark of their impact via their insertion into host genomes. With proper teasing, these sequences can relay information about the evolutionary history of transposons and their hosts. In a new publication, Larson and colleagues describe a previously unappreciated density of long interspersed element-1 (LINE-1) sequences that have been spliced (LINE-1 and other reverse transcribing elements are necessarily intronless). They provide data to suggest that the retention of these potentially deleterious splice sites in LINE-1 results from the sites' overlap with an important transcription factor binding site. These spliced LINE-1s (i.e., spliced integrated retrotransposed elements [SpiREs]) lose their ability to replicate, suggesting they are evolutionary dead ends. However, the lethality of this splicing could be an efficient means of blocking continued replication of LINE-1. In this way, the record of inactive LINE-1 sequences in the human genome revealed a new, though infrequent, event in the LINE-1 replication cycle and motivates future studies to test whether splicing might be another weapon in the anti-LINE-1 arsenal of host genomes.

  3. Hidden Structural Codes in Protein Intrinsic Disorder.

    PubMed

    Borkosky, Silvia S; Camporeale, Gabriela; Chemes, Lucía B; Risso, Marikena; Noval, María Gabriela; Sánchez, Ignacio E; Alonso, Leonardo G; de Prat Gay, Gonzalo

    2017-10-17

    Intrinsic disorder is a major structural category in biology, accounting for more than 30% of coding regions across the domains of life, yet consists of conformational ensembles in equilibrium, a major challenge in protein chemistry. Anciently evolved papillomavirus genomes constitute an unparalleled case for sequence to structure-function correlation in cases in which there are no folded structures. E7, the major transforming oncoprotein of human papillomaviruses, is a paradigmatic example among the intrinsically disordered proteins. Analysis of a large number of sequences of the same viral protein allowed for the identification of a handful of residues with absolute conservation, scattered along the sequence of its N-terminal intrinsically disordered domain, which intriguingly are mostly leucine residues. Mutation of these led to a pronounced increase in both α-helix and β-sheet structural content, reflected by drastic effects on equilibrium propensities and oligomerization kinetics, and uncovers the existence of local structural elements that oppose canonical folding. These folding relays suggest the existence of yet undefined hidden structural codes behind intrinsic disorder in this model protein. Thus, evolution pinpoints conformational hot spots that could have not been identified by direct experimental methods for analyzing or perturbing the equilibrium of an intrinsically disordered protein ensemble.

  4. Comparison of traditional phenotypic identification methods with partial 5' 16S rRNA gene sequencing for species-level identification of nonfermenting Gram-negative bacilli.

    PubMed

    Cloud, Joann L; Harmsen, Dag; Iwen, Peter C; Dunn, James J; Hall, Gerri; Lasala, Paul Rocco; Hoggan, Karen; Wilson, Deborah; Woods, Gail L; Mellmann, Alexander

    2010-04-01

    Correct identification of nonfermenting Gram-negative bacilli (NFB) is crucial for patient management. We compared phenotypic identifications of 96 clinical NFB isolates with identifications obtained by 5' 16S rRNA gene sequencing. Sequencing identified 88 isolates (91.7%) with >99% similarity to a sequence from the assigned species; 61.5% of sequencing results were concordant with phenotypic results, indicating the usability of sequencing to identify NFB.

  5. Preliminary Design Options for Meteor Burst Communications Systems Buoy Relays

    DTIC Science & Technology

    1986-12-01

    FIELDS BRAYTON OTTO ELECTROSTATIC FIELDS SUPERCRITICAL Figure 5.1. Structure of current power source technology for ocean applications. 32 L / P 9 t ~A...As in the sulphur dioxide cell, a low weight, high surface area, carbon positive elec- trode acts as a catalyst for the reduction of the cathode...Operating Transmit Power No. (Relay/Service) Type Covert Covert Mode Duty Cycle (watts) 2.1 Trans Ocean Relay Shore/Ship No Yes Remote 20 Msg/hr 0.9

  6. Relay Forward-Link File Management Services (MaROS Phase 2)

    NASA Technical Reports Server (NTRS)

    Allard, Daniel A.; Wallick, Michael N.; Hy, Franklin H.; Gladden, Roy E.

    2013-01-01

    This software provides the service-level functionality to manage the delivery of files from a lander mission repository to an orbiter mission repository for eventual spacelink relay by the orbiter asset on a specific communications pass. It provides further functions to deliver and track a set of mission-defined messages detailing lander authorization instructions and orbiter data delivery state. All of the information concerning these transactions is persisted in a database providing a high level of accountability of the forward-link relay process.

  7. 49 CFR 236.556 - Adjustment of relay.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Locomotives § 236.556 Adjustment of relay...

  8. 49 CFR 236.556 - Adjustment of relay.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Automatic Train Stop, Train Control and Cab Signal Systems Rules and Instructions; Locomotives § 236.556 Adjustment of relay...

  9. Orbiting deep space relay station. Volume 3: Implementation plan

    NASA Technical Reports Server (NTRS)

    Hunter, J. A.

    1979-01-01

    An implementation plan for the Orbiting Deep Space Relay Station (ODSRS) is described. A comparison of ODSRS life cycle costs to other configuration options meeting future communication requirements is presented.

  10. Energy-efficient algorithm for broadcasting in ad hoc wireless sensor networks.

    PubMed

    Xiong, Naixue; Huang, Xingbo; Cheng, Hongju; Wan, Zheng

    2013-04-12

    Broadcasting is a common and basic operation used to support various network protocols in wireless networks. To achieve energy-efficient broadcasting is especially important for ad hoc wireless sensor networks because sensors are generally powered by batteries with limited lifetimes. Energy consumption for broadcast operations can be reduced by minimizing the number of relay nodes based on the observation that data transmission processes consume more energy than data reception processes in the sensor nodes, and how to improve the network lifetime is always an interesting issue in sensor network research. The minimum-energy broadcast problem is then equivalent to the problem of finding the minimum Connected Dominating Set (CDS) for a connected graph that is proved NP-complete. In this paper, we introduce an Efficient Minimum CDS algorithm (EMCDS) with help of a proposed ordered sequence list. EMCDS does not concern itself with node energy and broadcast operations might fail if relay nodes are out of energy. Next we have proposed a Minimum Energy-consumption Broadcast Scheme (MEBS) with a modified version of EMCDS, and aimed at providing an efficient scheduling scheme with maximized network lifetime. The simulation results show that the proposed EMCDS algorithm can find smaller CDS compared with related works, and the MEBS can help to increase the network lifetime by efficiently balancing energy among nodes in the networks.

  11. Telerobot local-remote control architecture for space flight program applications

    NASA Technical Reports Server (NTRS)

    Zimmerman, Wayne; Backes, Paul; Steele, Robert; Long, Mark; Bon, Bruce; Beahan, John

    1993-01-01

    The JPL Supervisory Telerobotics (STELER) Laboratory has developed and demonstrated a unique local-remote robot control architecture which enables management of intermittent communication bus latencies and delays such as those expected for ground-remote operation of Space Station robotic systems via the Tracking and Data Relay Satellite System (TDRSS) communication platform. The current work at JPL in this area has focused on enhancing the technologies and transferring the control architecture to hardware and software environments which are more compatible with projected ground and space operational environments. At the local site, the operator updates the remote worksite model using stereo video and a model overlay/fitting algorithm which outputs the location and orientation of the object in free space. That information is relayed to the robot User Macro Interface (UMI) to enable programming of the robot control macros. This capability runs on a single Silicon Graphics Inc. machine. The operator can employ either manual teleoperation, shared control, or supervised autonomous control to manipulate the intended object. The remote site controller, called the Modular Telerobot Task Execution System (MOTES), runs in a multi-processor VME environment and performs the task sequencing, task execution, trajectory generation, closed loop force/torque control, task parameter monitoring, and reflex action. This paper describes the new STELER architecture implementation, and also documents the results of the recent autonomous docking task execution using the local site and MOTES.

  12. Reliable quantum communication over a quantum relay channel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gyongyosi, Laszlo, E-mail: gyongyosi@hit.bme.hu; Imre, Sandor

    2014-12-04

    We show that reliable quantum communication over an unreliable quantum relay channels is possible. The coding scheme combines the results on the superadditivity of quantum channels and the efficient quantum coding approaches.

  13. KSC-2013-4406

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  14. KSC-2013-4431

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, a United Launch Alliance Atlas V rocket, with its Centaur second stage atop, stands in the Vertical Integration Facility as preparations continue for lift off of the Tracking and Data Relay Satellite, or TDRS-L. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  15. KSC-2013-4407

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  16. KSC-2013-4415

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket positioned in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  17. KSC-2013-4418

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur second stage that will help boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  18. KSC-2013-4421

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, a technician supports preparations for lifting the Centaur second stage of the United Launch Alliance rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  19. KSC-2013-4427

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, a Centaur second stage is lifted for stacking atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  20. KSC-2013-3791

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  1. KSC-2013-4410

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  2. KSC-2013-4398

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41, a crane is positioned to support stacking of the United Launch Alliance Atlas V rocket that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  3. KSC-2013-4400

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, engineers and technicians prepare the United Launch Alliance Atlas V rocket for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  4. KSC-2013-4389

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  5. KSC-2013-3793

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  6. KSC-2013-4423

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, engineers and technicians support lifting a Centaur second stage for stacking atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  7. KSC-2013-4417

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur second stage that will help boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  8. KSC-2013-4411

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  9. KSC-2013-4425

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, engineers and technicians support lifting a Centaur second stage for stacking atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  10. KSC-2013-3789

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur upper stage that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  11. KSC-2013-3794

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  12. KSC-2013-4393

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  13. KSC-2013-4408

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, a technician supports lifting of a United Launch Alliance Atlas V rocket in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  14. KSC-2013-4403

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  15. KSC-2013-4416

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket positioned in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  16. KSC-2013-3784

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  17. KSC-2013-4405

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  18. KSC-2013-4422

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, engineers and technicians support preparations for lifting the Centaur second stage of the United Launch Alliance rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  19. KSC-2013-4430

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, engineers and technicians inspect a Centaur second stage that was just stacked atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  20. KSC-2013-4392

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  1. KSC-2013-4401

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, engineers and technicians prepare the United Launch Alliance Atlas V rocket for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  2. KSC-2013-3788

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  3. KSC-2013-4414

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  4. KSC-2013-4424

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, engineers and technicians support lifting a Centaur second stage for stacking atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  5. KSC-2013-4419

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur second stage that will help boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  6. KSC-2013-3787

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  7. KSC-2013-4390

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being prepared for transport from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  8. KSC-2013-4399

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, engineers and technicians prepare the United Launch Alliance Atlas V rocket for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  9. KSC-2013-4409

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, the first stage of the United Launch Alliance Atlas V rocket is lifted for stacking in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  10. KSC-2013-4426

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Launch Complex 41, a Centaur second stage is lifted for stacking atop a United Launch Alliance Atlas V rocket that will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  11. KSC-2013-3785

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  12. KSC-2013-4391

    NASA Image and Video Library

    2013-12-12

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V first stage booster that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported from the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station to Launch Complex 41. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Kim Shiflett

  13. KSC-2013-4397

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41, a crane is positioned to support stacking of the United Launch Alliance Atlas V rocket that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  14. Digital transceiver design for two-way AF-MIMO relay systems with imperfect CSI

    NASA Astrophysics Data System (ADS)

    Hu, Chia-Chang; Chou, Yu-Fei; Chen, Kui-He

    2013-09-01

    In the paper, combined optimization of the terminal precoders/equalizers and single-relay precoder is proposed for an amplify-and-forward (AF) multiple-input multiple-output (MIMO) two-way single-relay system with correlated channel uncertainties. Both terminal transceivers and relay precoding matrix are designed based on the minimum mean square error (MMSE) criterion when terminals are unable to erase completely self-interference due to imperfect correlated channel state information (CSI). This robust joint optimization problem of beamforming and precoding matrices under power constraints belongs to neither concave nor convex so that a nonlinear matrix-form conjugate gradient (MCG) algorithm is applied to explore local optimal solutions. Simulation results show that the robust transceiver design is able to overcome effectively the loss of bit-error-rate (BER) due to inclusion of correlated channel uncertainties and residual self-interference.

  15. Continuous-variable quantum cryptography with an untrusted relay: Detailed security analysis of the symmetric configuration

    NASA Astrophysics Data System (ADS)

    Ottaviani, Carlo; Spedalieri, Gaetana; Braunstein, Samuel L.; Pirandola, Stefano

    2015-02-01

    We consider the continuous-variable protocol of Pirandola et al. [arXiv:1312.4104] where the secret key is established by the measurement of an untrusted relay. In this network protocol, two authorized parties are connected to an untrusted relay by insecure quantum links. Secret correlations are generated by a continuous-variable Bell detection performed on incoming coherent states. In the present work we provide a detailed study of the symmetric configuration, where the relay is midway between the parties. We analyze symmetric eavesdropping strategies against the quantum links explicitly showing that, at fixed transmissivity and thermal noise, two-mode coherent attacks are optimal, manifestly outperforming one-mode collective attacks based on independent entangling cloners. Such an advantage is shown both in terms of security threshold and secret-key rate.

  16. Video Relay Service for Signing Deaf - Lessons Learnt from a Pilot Study

    NASA Astrophysics Data System (ADS)

    Ponsard, Christophe; Sutera, Joelle; Henin, Michael

    The generalization of high speed Internet, efficient compression techniques and low cost hardware have resulted in low cost video communication since the year 2000. For the Deaf community, this enables native communication in sign language and a better communication with hearing people over the phone. This implies that Video Relay Service can take over the old Text Relay Service which is less natural and requires mastering written language. A number of such services have developed throughout the world. The objectives of this paper are to present the experience gained in the Walloon Region of Belgium, to share a number of lessons learnt, and to provide recommendations at the technical, user adoption and political levels. A survey of video relay services around the world is presented together with the feedback from users both before and after using the pilot service.

  17. Optical deep space communication via relay satellite

    NASA Technical Reports Server (NTRS)

    Gagliardi, R. M.; Vilnrotter, V. A.; Dolinar, S. J., Jr.

    1981-01-01

    The possible use of an optical for high rate data transmission from a deep space vehicle to an Earth-orbiting relay satellite while RF links are envisioned for the relay to Earth link was studied. A preliminary link analysis is presented for initial sizing of optical components and power levels, in terms of achievable data rates and feasible range distances. Modulation formats are restricted to pulsed laser operation, involving bot coded and uncoded schemes. The advantage of an optical link over present RF deep space link capabilities is shown. The problems of acquisition, pointing and tracking with narrow optical beams are presented and discussed. Mathematical models of beam trackers are derived, aiding in the design of such systems for minimizing beam pointing errors. The expected orbital geometry between spacecraft and relay satellite, and its impact on beam pointing dynamics are discussed.

  18. Localization and cooperative communication methods for cognitive radio

    NASA Astrophysics Data System (ADS)

    Duval, Olivier

    We study localization of nearby nodes and cooperative communication for cognitive radios. Cognitive radios sensing their environment to estimate the channel gain between nodes can cooperate and adapt their transmission power to maximize the capacity of the communication between two nodes. We study the end-to-end capacity of a cooperative relaying scheme using orthogonal frequency-division modulation (OFDM) modulation, under power constraints for both the base station and the relay station. The relay uses amplify-and-forward and decode-and-forward cooperative relaying techniques to retransmit messages on a subset of the available subcarriers. The power used in the base station and the relay station transmitters is allocated to maximize the overall system capacity. The subcarrier selection and power allocation are obtained based on convex optimization formulations and an iterative algorithm. Additionally, decode-and-forward relaying schemes are allowed to pair source and relayed subcarriers to increase further the capacity of the system. The proposed techniques outperforms non-selective relaying schemes over a range of relay power budgets. Cognitive radios can be used for opportunistic access of the radio spectrum by detecting spectrum holes left unused by licensed primary users. We introduce a spectrum holes detection approach, which combines blind modulation classification, angle of arrival estimation and number of sources detection. We perform eigenspace analysis to determine the number of sources, and estimate their angles of arrival (AOA). In addition, we classify detected sources as primary or secondary users with their distinct second-orde one-conjugate cyclostationarity features. Extensive simulations carried out indicate that the proposed system identifies and locates individual sources correctly, even at -4 dB signal-to-noise ratios (SNR). In environments with a high density of scatterers, several wireless channels experience nonline-of-sight (NLOS) condition, increasing the localization error, even when the AOA estimate is accurate. We present a real-time localization solver (RTLS) for time-of-arrival (TOA) estimates using ray-tracing methods on the map of the geometry of walls and compare its performance with classical TOA trilateration localization methods. Extensive simulations and field trials for indoor environments show that our method increases the coverage area from 1.9% of the floor to 82.3 % and the accuracy by a 10-fold factor when compared with trilateration. We implemented our ray tracing model in C++ using the CGAL computational geometry algorithm library. We illustrate the real-time property of our RTLS that performs most ray tracing tasks in a preprocessing phase with time and space complexity analyses and profiling of our software.

  19. Mutual-Information-Based Incremental Relaying Communications for Wireless Biomedical Implant Systems

    PubMed Central

    Liao, Yangzhe; Cai, Qing; Ai, Qingsong; Liu, Quan

    2018-01-01

    Network lifetime maximization of wireless biomedical implant systems is one of the major research challenges of wireless body area networks (WBANs). In this paper, a mutual information (MI)-based incremental relaying communication protocol is presented where several on-body relay nodes and one coordinator are attached to the clothes of a patient. Firstly, a comprehensive analysis of a system model is investigated in terms of channel path loss, energy consumption, and the outage probability from the network perspective. Secondly, only when the MI value becomes smaller than the predetermined threshold is data transmission allowed. The communication path selection can be either from the implanted sensor to the on-body relay then forwards to the coordinator or from the implanted sensor to the coordinator directly, depending on the communication distance. Moreover, mathematical models of quality of service (QoS) metrics are derived along with the related subjective functions. The results show that the MI-based incremental relaying technique achieves better performance in comparison to our previous proposed protocol techniques regarding several selected performance metrics. The outcome of this paper can be applied to intra-body continuous physiological signal monitoring, artificial biofeedback-oriented WBANs, and telemedicine system design. PMID:29419784

  20. Mutual-Information-Based Incremental Relaying Communications for Wireless Biomedical Implant Systems.

    PubMed

    Liao, Yangzhe; Leeson, Mark S; Cai, Qing; Ai, Qingsong; Liu, Quan

    2018-02-08

    Network lifetime maximization of wireless biomedical implant systems is one of the major research challenges of wireless body area networks (WBANs). In this paper, a mutual information (MI)-based incremental relaying communication protocol is presented where several on-body relay nodes and one coordinator are attached to the clothes of a patient. Firstly, a comprehensive analysis of a system model is investigated in terms of channel path loss, energy consumption, and the outage probability from the network perspective. Secondly, only when the MI value becomes smaller than the predetermined threshold is data transmission allowed. The communication path selection can be either from the implanted sensor to the on-body relay then forwards to the coordinator or from the implanted sensor to the coordinator directly, depending on the communication distance. Moreover, mathematical models of quality of service (QoS) metrics are derived along with the related subjective functions. The results show that the MI-based incremental relaying technique achieves better performance in comparison to our previous proposed protocol techniques regarding several selected performance metrics. The outcome of this paper can be applied to intra-body continuous physiological signal monitoring, artificial biofeedback-oriented WBANs, and telemedicine system design.

  1. Performance analysis of optimal power allocation in wireless cooperative communication systems

    NASA Astrophysics Data System (ADS)

    Babikir Adam, Edriss E.; Samb, Doudou; Yu, Li

    2013-03-01

    Cooperative communication has been recently proposed in wireless communication systems for exploring the inherent spatial diversity in relay channels.The Amplify-and-Forward (AF) cooperation protocols with multiple relays have not been sufficiently investigated even if it has a low complexity in term of implementation. We consider in this work a cooperative diversity system in which a source transmits some information to a destination with the help of multiple relay nodes with AF protocols and investigate the optimality of allocating powers both at the source and the relays system by optimizing the symbol error rate (SER) performance in an efficient way. Firstly we derive a closedform SER formulation for MPSK signal using the concept of moment generating function and some statistical approximations in high signal to noise ratio (SNR) for the system under studied. We then find a tight corresponding lower bound which converges to the same limit as the theoretical upper bound and develop an optimal power allocation (OPA) technique with mean channel gains to minimize the SER. Simulation results show that our scheme outperforms the equal power allocation (EPA) scheme and is tight to the theoretical approximation based on the SER upper bound in high SNR for different number of relays.

  2. 7 CFR 1767.20 - Plant accounts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 367Underground Conductors and Devices 368Line Transformers 369Services 370Meters 371Installations on Customers... and interlocks, current transformers, potential transformers, protective relays, isolated panels and..., compensators, resistors, starting transformers, current transformers, potential transformers, protective relays...

  3. 7 CFR 1767.20 - Plant accounts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 367Underground Conductors and Devices 368Line Transformers 369Services 370Meters 371Installations on Customers... and interlocks, current transformers, potential transformers, protective relays, isolated panels and..., compensators, resistors, starting transformers, current transformers, potential transformers, protective relays...

  4. 7 CFR 1767.20 - Plant accounts.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 367Underground Conductors and Devices 368Line Transformers 369Services 370Meters 371Installations on Customers... and interlocks, current transformers, potential transformers, protective relays, isolated panels and..., compensators, resistors, starting transformers, current transformers, potential transformers, protective relays...

  5. 7 CFR 1767.20 - Plant accounts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 367Underground Conductors and Devices 368Line Transformers 369Services 370Meters 371Installations on Customers... and interlocks, current transformers, potential transformers, protective relays, isolated panels and..., compensators, resistors, starting transformers, current transformers, potential transformers, protective relays...

  6. 7 CFR 1767.20 - Plant accounts.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 367Underground Conductors and Devices 368Line Transformers 369Services 370Meters 371Installations on Customers... and interlocks, current transformers, potential transformers, protective relays, isolated panels and..., compensators, resistors, starting transformers, current transformers, potential transformers, protective relays...

  7. CALIPSO Instrument OFF

    Atmospheric Science Data Center

    2013-12-05

    ... The CALIPSO payload was commanded to SAFE Mode and the laser relays opened this morning, May 15, during the 14:21 Aussaguel pass.  The laser relays were opened just as the proton levels were exceeding the 10 pfu ...

  8. Relay Protection and Automation Systems Based on Programmable Logic Integrated Circuits

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lashin, A. V., E-mail: LashinAV@lhp.ru; Kozyrev, A. V.

    One of the most promising forms of developing the apparatus part of relay protection and automation devices is considered. The advantages of choosing programmable logic integrated circuits to obtain adaptive technological algorithms in power system protection and control systems are pointed out. The technical difficulties in the problems which today stand in the way of using relay protection and automation systems are indicated and a new technology for solving these problems is presented. Particular attention is devoted to the possibility of reconfiguring the logic of these devices, using programmable logic integrated circuits.

  9. Achievable degrees of freedom of MIMO two-way relay interference channel with delayed CSIT

    NASA Astrophysics Data System (ADS)

    Li, Qingyun; Wu, Gang; Li, Shaoqian

    2016-10-01

    In this paper, assuming each node has delayed channel state information at the transmitter (CSIT), we investigate the achievable degrees of freedom (DOF) of MIMO two-way relay interference channel in frequency division duplex (FDD) systems, where there are K user pairs (i.e., 2K users) and each user in a user pair exchanges messages with the other user in the same user pair simultaneously via an intermediate relay. We propose a two-stage transmission scheme and derive the closed-form expressions for its achievable DOF.

  10. Isolation contactor state control system

    DOEpatents

    Bissontz, Jay E.

    2017-05-16

    A controller area network (CAN) installed on a hybrid electric vehicle provides one node with control of high voltage power distribution system isolation contactors and the capacity to energize a secondary electro-mechanical relay device. The output of the secondary relay provides a redundant and persistent backup signal to the output of the node. The secondary relay is relatively immune to CAN message traffic interruptions and, as a result, the high voltage isolation contactor(s) are less likely to transition open in the event that the intelligent output driver should fail.

  11. Counterfactual quantum cryptography network with untrusted relay

    NASA Astrophysics Data System (ADS)

    Chen, Yuanyuan; Gu, Xuemei; Jiang, Dong; Xie, Ling; Chen, Lijun

    2015-07-01

    Counterfactual quantum cryptography allows two remote parties to share a secret key even though a physical particle is not in fact transmitted through the quantum channel. In order to extend the scope of counterfactual quantum cryptography, we use an untrusted relay to construct a multi-user network. The implementation issues are discussed to show that the scheme can be realized with current technologies. We also prove the practical security advantages of the scheme by eliminating the probability that an eavesdropper can directly access the signal or an untrusted relay can perform false operations.

  12. Optical determination of the electronic coupling and intercalation geometry of thiazole orange homodimer in DNA

    NASA Astrophysics Data System (ADS)

    Cunningham, Paul D.; Bricker, William P.; Díaz, Sebastián A.; Medintz, Igor L.; Bathe, Mark; Melinger, Joseph S.

    2017-08-01

    Sequence-selective bis-intercalating dyes exhibit large increases in fluorescence in the presence of specific DNA sequences. This property makes this class of fluorophore of particular importance to biosensing and super-resolution imaging. Here we report ultrafast transient anisotropy measurements of resonance energy transfer (RET) between thiazole orange (TO) molecules in a complex formed between the homodimer TOTO and double-stranded (ds) DNA. Biexponential homo-RET dynamics suggest two subpopulations within the ensemble: 80% intercalated and 20% non-intercalated. Based on the application of the transition density cube method to describe the electronic coupling and Monte Carlo simulations of the TOTO/dsDNA geometry, the dihedral angle between intercalated TO molecules is estimated to be 81° ± 5°, corresponding to a coupling strength of 45 ± 22 cm-1. Dye intercalation with this geometry is found to occur independently of the underlying DNA sequence, despite the known preference of TOTO for the nucleobase sequence CTAG. The non-intercalated subpopulation is inferred to have a mean inter-dye separation distance of 19 Å, corresponding to coupling strengths between 0 and 25 cm-1. This information is important to enable the rational design of energy transfer systems that utilize TOTO as a relay dye. The approach used here is generally applicable to determining the electronic coupling strength and intercalation configuration of other dimeric bis-intercalators.

  13. Complete Genome Sequence of Pigmentation Negative Yersinia Pestis strain Cadman Running head: Complete Genome Sequence of Y. pestis strain Cadman

    DTIC Science & Technology

    2016-10-27

    Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, USA 9 10 11 Running head: Complete Genome Sequence of Y. pestis strain Cadman...1 Complete Genome Sequence of Pigmentation Negative Yersinia pestis strain Cadman 1 2 3 Sean Lovetta, Kitty Chaseb, Galina Korolevaa, Gustavo...we report the genome sequence of Yersinia pestis strain Cadman, an attenuated strain 25 lacking the pgm locus. Y. pestis is the causative agent of

  14. Soil Chemical Property Changes in Eggplant/Garlic Relay Intercropping Systems under Continuous Cropping

    PubMed Central

    Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen; Zhang, Mengru; Zhang, Hongjing

    2014-01-01

    Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercropping eggplant with garlic (Allium sativum L.) on soil enzyme activities, available nutrient contents, and pH value under a plastic tunnel. Three treatments were in triplicate using randomized block design: eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). The major results are as follows: (1) the activities of soil invertase, urease, and alkaline phosphatase were generally enhanced in NG and GG treatments; (2) relay intercropping significantly increased the soil available nutrient contents, and they were mostly higher in GG than NG. On April 11, 2011, the eggplant/garlic co-growth stage, the available nitrogen content in GG was 76.30 mg·kg−1, significantly higher than 61.95 mg·kg−1 in NG. For available potassium on April 17, 2012, they were 398.48 and 387.97 mg·kg−1 in NG and GG, both were significantly higher than 314.84 mg·kg−1 in CK; (3) the soil pH showed a significantly higher level in NG treatment, but lower in GG treatment compared with CK. For the last samples in 2012, soil pH in NG and GG were 7.70 and 7.46, the highest and lowest one among them; (4) the alkaline phosphatase activity and pH displayed a similar decreasing trend with continuous cropping. These findings indicate that relay intercropping eggplant with garlic could be an ideal farming system to effectively improve soil nutrient content, increase soil fertility, and alleviate soil sickness to some extent. These findings are important in helping to develop sustainable eggplant production. PMID:25340875

  15. Soil chemical property changes in eggplant/garlic relay intercropping systems under continuous cropping.

    PubMed

    Wang, Mengyi; Wu, Cuinan; Cheng, Zhihui; Meng, Huanwen; Zhang, Mengru; Zhang, Hongjing

    2014-01-01

    Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercropping eggplant with garlic (Allium sativum L.) on soil enzyme activities, available nutrient contents, and pH value under a plastic tunnel. Three treatments were in triplicate using randomized block design: eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). The major results are as follows: (1) the activities of soil invertase, urease, and alkaline phosphatase were generally enhanced in NG and GG treatments; (2) relay intercropping significantly increased the soil available nutrient contents, and they were mostly higher in GG than NG. On April 11, 2011, the eggplant/garlic co-growth stage, the available nitrogen content in GG was 76.30 mg·kg(-1), significantly higher than 61.95 mg·kg(-1) in NG. For available potassium on April 17, 2012, they were 398.48 and 387.97 mg·kg(-1) in NG and GG, both were significantly higher than 314.84 mg·kg(-1) in CK; (3) the soil pH showed a significantly higher level in NG treatment, but lower in GG treatment compared with CK. For the last samples in 2012, soil pH in NG and GG were 7.70 and 7.46, the highest and lowest one among them; (4) the alkaline phosphatase activity and pH displayed a similar decreasing trend with continuous cropping. These findings indicate that relay intercropping eggplant with garlic could be an ideal farming system to effectively improve soil nutrient content, increase soil fertility, and alleviate soil sickness to some extent. These findings are important in helping to develop sustainable eggplant production.

  16. Isolation and molecular characterization of a urease-negative Actinobacillus pleuropneumoniae mutant.

    PubMed

    Ito, Hiroya; Takahashi, Sayaka; Asai, Tetsuo; Tamura, Yutaka; Yamamoto, Koshi

    2018-01-01

    An atypical urease-negative mutant of Actinobacillus pleuropneumoniae serovar 2 was isolated in Japan. Nucleotide sequence analysis of the urease gene cluster revealed that the insertion of a short DNA sequence into the cbiM gene was responsible for the urease-negative activity of the mutant. Veterinary diagnostic laboratories should be watchful for the presence of aberrant urease-negative A. pleuropneumoniae isolates.

  17. 32 CFR 321.13 - Exemptions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... investigations and relay law enforcement information without compromise of the information, protection of... enable DSS to conduct certain investigations and relay law enforcement information without compromise of the information, protection of investigative techniques and efforts employed, and identities of...

  18. 32 CFR 318.16 - Exemption rules.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) From subsection (c)(3) because it will enable DTRA to safeguard certain investigations and relay law... provide protection against notification of investigatory material including certain reciprocal... conduct certain investigations and relay law enforcement information without compromise of the information...

  19. 32 CFR 318.16 - Exemption rules.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) From subsection (c)(3) because it will enable DTRA to safeguard certain investigations and relay law... provide protection against notification of investigatory material including certain reciprocal... conduct certain investigations and relay law enforcement information without compromise of the information...

  20. Latest Changes to NASA's Laser Communication Relay Demonstration Project

    NASA Technical Reports Server (NTRS)

    Edwards, Bernard L.; Israel, David J.; Vithlani, Seema K.

    2018-01-01

    Over the last couple of years, NASA has been making changes to the Laser Communications Relay Demonstration Project (LCRD), a joint project between NASA's Goddard Space Flight Center (GSFC), the Jet Propulsion Laboratory, California Institute of Technology (JPL), and the Massachusetts Institute of Technology Lincoln Laboratory (MIT/LL). The changes made makes LCRD more like a future Earth relay system that has both high speed optical and radio frequency links. This will allow LCRD to demonstrate a more detailed concept of operations for a future operational mission critical Earth relay. LCRD is expected to launch in June 2019 and is expected to be followed a couple of years later with a prototype user terminal on the International Space Station. LCRD's architecture will allow it to serve as a testbed in space and this paper will provide an update of its planned capabilities and experiments.

  1. KSC-2013-3786

    NASA Image and Video Library

    2013-11-01

    CAPE CANAVERAL, Fla. – The United Launch Alliance Atlas V launch vehicle, left, and Centaur upper stage that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to the hangar at the Atlas Spaceflight Operations Center on Cape Canaveral Air Force Station for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Jim Grossman

  2. KSC-2013-4402

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, engineers and technicians support lifting the first stage of the United Launch Alliance Atlas V rocket during stacking operations in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  3. KSC-2013-4413

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, a technician support lifting the first stage of the United Launch Alliance Atlas V rocket during stacking operations in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  4. KSC-2013-4420

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – The United Launch Alliance Centaur second stage that will help boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit arrives at Cape Canaveral Air Force Station's Launch Complex 41. It will be lifted and mounted atop the Atlas V first stage already in position inside the Vertical Integration Facility. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  5. KSC-2013-4412

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, engineers and technicians support lifting the first stage of the United Launch Alliance Atlas V rocket during stacking operations in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  6. KSC-2013-3782

    NASA Image and Video Library

    2013-11-01

    PORT CANAVERAL, Fla. – Following arrival at Port Canaveral, Fla., the United Launch Alliance Atlas V first stage and Centaur upper stage that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to Cape Canaveral Air Force Station's Atlas Spaceflight Operations Center for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Kim Shiflett

  7. KSC-2013-4404

    NASA Image and Video Library

    2013-12-13

    CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station, engineers and technicians support lifting the first stage of the United Launch Alliance Atlas V rocket during stacking operations in the Vertical Integration Facility at Launch Complex 41. The vehicle will be used to boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft to orbit. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/Charisse Nahser

  8. KSC-2013-3781

    NASA Image and Video Library

    2013-11-01

    PORT CANAVERAL, Fla. – Following arrival at Port Canaveral, Fla., the United Launch Alliance Atlas V first stage and Centaur upper stage that will boost the Tracking and Data Relay Satellite, or TDRS-L, spacecraft into orbit is being transported to Cape Canaveral Air Force Station's Atlas Spaceflight Operations Center for checkout in preparation for launch. TDRS-L is the second of three next-generation satellites designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay service to missions such as the Hubble Space Telescope and International Space Station. For more information, visit: http://www.nasa.gov/content/tracking-and-data-relay-satellite-tdrs/ Photo credit: NASA/ Kim Shiflett

  9. Telecommunications Relay Support of the Mars Phoenix Lander Mission

    NASA Technical Reports Server (NTRS)

    Edwards, Charles D., Jr.; Erickson, James K.; Gladden, Roy E.; Guinn, Joseph R.; Ilott, Peter A.; Jai, Benhan; Johnston, Martin D.; Kornfeld, Richard P.; Martin-Mur, Tomas J.; McSmith, Gaylon W.; hide

    2010-01-01

    The Phoenix Lander, first of NASA's Mars Scout missions, arrived at the Red Planet on May 25, 2008. From the moment the lander separated from its interplanetary cruise stage shortly before entry, the spacecraft could no longer communicate directly with Earth, and was instead entirely dependent on UHF relay communications via an international network of orbiting Mars spacecraft, including NASA's 2001 Mars Odyssey (ODY) and Mars Reconnaissance Orbiter (MRO) spacecraft, as well as ESA's Mars Express (MEX) spacecraft. All three orbiters captured critical event telemetry and/or tracking data during Phoenix Entry, Descent and Landing. During the Phoenix surface mission, ODY and MRO provided command and telemetry services, far surpassing the original data return requirements. The availability of MEX as a backup relay asset enhanced the robustness of the surface relay plan. In addition to telecommunications services, Doppler tracking observables acquired on the UHF link yielded an accurate position for the Phoenix landing site.

  10. Bacteriophage as models for virus removal from Pacific oysters (Crassostrea gigas) during re-laying.

    PubMed Central

    Humphrey, T. J.; Martin, K.

    1993-01-01

    A study was undertaken to examine the feasibility of using naturally-occurring bacteriophages to assess the impact of re-laying on levels of viral contamination in Crassostrea gigas, the Pacific oyster. Two phages were chosen. One, male-specific (F+), was enumerated using Salmonella typhimurium. The other, a somatic phage, was detected using an, as yet, uncharacterized Escherichia coli. Investigations, using a variety of re-laying sites, demonstrated that numbers of F+ phage in oyster tissue declined more rapidly than those of somatic phage. For example, in oysters placed in commercially-used sea water ponds, F+ phage reached undetectable levels within 2-3 weeks, whereas somatic phage could still be detected 5 weeks after re-laying. The studies suggest that F+ phage may not be a suitable indicator for virus removal and that somatic phage may be better suited to this role. PMID:8405159

  11. Design And Implementation Of PID Controller Using Relay Feedback On TRMS (Twin Rotor MIMO System)

    NASA Astrophysics Data System (ADS)

    Shah, Dipesh H.

    2011-12-01

    Today, many process control problems can be adequately and routinely solved by conventional PID control strategies. The overriding reason that the PID controller is so widely accepted is its simple structure which has proved to be very robust with regard to many commonly met process control problems as for instance disturbances and nonlinearities. Relay feedback methods have been widely used in tuning proportional-integral-derivative controllers due to its closed loop nature. In this work, Relay based PID controller is designed and successfully implemented on TRMS (Twin Rotor MIMO System) in SISO and MIMO configurations. The performance of a Relay based PID controller for control of TRMS is investigated and performed satisfactorily. The system shares some features with a helicopter, such as important interactions between the vertical and horizontal motions. The RTWT toolbox in the MATLAB environment is used to perform real-time experiments.

  12. Improved Iterative Decoding of Network-Channel Codes for Multiple-Access Relay Channel.

    PubMed

    Majumder, Saikat; Verma, Shrish

    2015-01-01

    Cooperative communication using relay nodes is one of the most effective means of exploiting space diversity for low cost nodes in wireless network. In cooperative communication, users, besides communicating their own information, also relay the information of other users. In this paper we investigate a scheme where cooperation is achieved using a common relay node which performs network coding to provide space diversity for two information nodes transmitting to a base station. We propose a scheme which uses Reed-Solomon error correcting code for encoding the information bit at the user nodes and convolutional code as network code, instead of XOR based network coding. Based on this encoder, we propose iterative soft decoding of joint network-channel code by treating it as a concatenated Reed-Solomon convolutional code. Simulation results show significant improvement in performance compared to existing scheme based on compound codes.

  13. Auction-based Security Game for Multiuser Cooperative Networks

    NASA Astrophysics Data System (ADS)

    Wang, An; Cai, Yueming; Yang, Wendong; Cheng, Yunpeng

    2013-04-01

    In this paper, we develop an auction-based algorithm to allocate the relay power efficiently to improve the system secrecy rate in a cooperative network, where several source-destination pairs and one cooperative relay are involved. On the one hand, the cooperative relay assists these pairs to transmit under a peak power constraint. On the other hand, the relay is untrusty and is also a passive eavesdropper. The whole auction process is completely distributed and no instantaneous channel state information exchange is needed. We also prove the existence and uniqueness of the Nash Equilibrium (NE) for the proposed power auction game. Moreover, the Pareto optimality is also validated. Simulation results show that our proposed auction-based algorithm can effectively improve the system secrecy rate. Besides, the proposed auction-based algorithm can converge to the unique NE point within a finite number of iterations. More interestingly, we also find that the proposed power auction mechanism is cheat-proof.

  14. Mimicking the photosynthetic triplet energy-transfer relay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gust, D.; Moore, T.A.; Moore, A.L.

    1993-06-30

    In the reaction centers of photosynthetic organisms, chlorophyll triplet states are sometimes formed by recombination of charge-separated intermediates. These triplets are excellent sensitizers for singlet oxygen formation. Carotenoid polyenes can provide photoprotection from singlet oxygen generation by rapidly quenching chlorophyll triplet states via triplet-triplet energy transfer. Because in bacteria the reaction center carotenoid is not located adjacent to the bacteriochlorophyll special pair, which is the origin of the charge separation, it has been postulated that quenching may occur via a triplet relay involving an intermediate chlorophyll monomer. We now report the synthesis and spectroscopic study of a covalently linked carotenoidmore » (C)-porphyrin (P)-pyropheophorbide (Ppd) triad molecule which mimics this triplet relay. The pyropheophorbide singlet-state C-P-[sup 1]Ppd (generated by direct excitation or energy transfer from the attached porphyrin) undergoes intersystem crossing to the triplet C-P-[sup 3]Ppd. In oxygen-free solutions, this triplet decays to [sup 3]C-p-Ppd through a triplet-transfer relay involving an intermediate C-[sup 3]P-Ppd species. In aerated solutions, quenching of C-P-[sup 3]Ppd by the attached carotenoid competes with singlet oxygen sensitization and thus provides a degree of photoprotection. In a similar traid containing a zinc porphyrin moiety, triplet transfer is slow due to the higher energy of the C-[sup 3]P[sub Zn]-Ppd intermediate, and photoprotection via the relay is nonexistent. The triplet relay ceases to function at low temperatures in both the natural and biomimetic cases due to the endergonicity of the first step. 37 refs., 6 figs., 1 tab.« less

  15. Endovascular treatment of patients with types A and B thoracic aortic dissection using Relay thoracic stent-grafts: results from the RESTORE Patient Registry.

    PubMed

    Zipfel, Burkhart; Czerny, Martin; Funovics, Martin; Coppi, Gioacchino; Ferro, Carlo; Rousseau, Hervé; Berti, Sergio; Tealdi, Domenico G; Riambau, Vincent; Mangialardi, Nicola; Sassi, Carlo

    2011-04-01

    To evaluate the safety and performance of Relay stent-grafts in patients with acute or chronic aortic dissections. Patients with types A or B aortic dissections suitable for treatment with Relay stent-grafts and followed for 2 years after thoracic endovascular aortic repair (TEVAR) were identified from a company-sponsored registry database established in January 2006. Ninety-one consecutive patients (69 men; mean age 65 years) underwent TEVAR with Relay stent-grafts for dissection. Most patients (76, 84%) had type B dissections; 61 of all patients were classified as chronic and 30 as acute. The technical success rate was 95% (97% in acute, 95% in chronic, and 93% in type B dissections). The type I endoleak rate was 7% (7% in acute and 8% in chronic dissections); all occurred in patients with type B dissections. Paraplegia, paraparesis, and stroke occurred in 4, 1, and 2 patients, respectively; 2 cases of paraplegia occurred in patients with acute type B dissections. Thirty-day mortality was 8% (13% in acute and 5% in chronic dissections); all deaths occurred in patients with type B dissections. The 2-year survival rate was 82% in the overall population and 84% in patients with type B dissections. The combination of Relay's features, such as stent conformability, radial force, atraumatic design, and controlled deployment and fixation, may contribute to the safety of the Relay stent-grafts for the treatment of thoracic aortic dissections, including acute and chronic type B dissections.

  16. Mars Reconnaissance Orbiter Navigation Strategy for Dual Support of Insight and ExoMars Entry, Descent and Landing Demonstrator Module in 2016

    NASA Technical Reports Server (NTRS)

    Wagner, Sean V.; Menon, Premkumar R.; Chung, Min-Kun J.; Williams, Jessica L.

    2015-01-01

    Mars Reconnaissance Orbiter (MRO) will support NASA's InSight Mission and ESA's ExoMars Entry, Descent and Landing Demonstrator Module (EDM) in the fall of 2016 when both landers arrive at Mars. MRO provided relay support during the Entry, Descent and Landing (EDL) sequences of Mars Phoenix Lander in 2008 and the Mars Science Laboratory in 2012. Unlike these missions, MRO will coordinate between two EDL events separated by only three weeks: InSight on September 28, 2016 and EDM on October 19, 2016. This paper describes MRO Navigation's maneuver strategy to move MRO's ascending node to meet the In- Sight EDL phasing requirement and support EDM.

  17. Diversity-based acoustic communication with a glider in deep water.

    PubMed

    Song, H C; Howe, Bruce M; Brown, Michael G; Andrew, Rex K

    2014-03-01

    The primary use of underwater gliders is to collect oceanographic data within the water column and periodically relay the data at the surface via a satellite connection. In summer 2006, a Seaglider equipped with an acoustic recording system received transmissions from a broadband acoustic source centered at 75 Hz deployed on the bottom off Kauai, Hawaii, while moving away from the source at ranges up to ∼200 km in deep water and diving up to 1000-m depth. The transmitted signal was an m-sequence that can be treated as a binary-phase shift-keying communication signal. In this letter multiple receptions are exploited (i.e., diversity combining) to demonstrate the feasibility of using the glider as a mobile communication gateway.

  18. 47 CFR 78.27 - License conditions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., modifications, assignments or transfers of control, and renewals) in the Cable Television Relay Service to serve cable television systems and other eligible systems, shall contain the condition that cable television... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES CABLE TELEVISION RELAY...

  19. 47 CFR 78.27 - License conditions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., modifications, assignments or transfers of control, and renewals) in the Cable Television Relay Service to serve cable television systems and other eligible systems, shall contain the condition that cable television... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES CABLE TELEVISION RELAY...

  20. 47 CFR 78.27 - License conditions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., modifications, assignments or transfers of control, and renewals) in the Cable Television Relay Service to serve cable television systems and other eligible systems, shall contain the condition that cable television... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES CABLE TELEVISION RELAY...

  1. 47 CFR 78.27 - License conditions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., modifications, assignments or transfers of control, and renewals) in the Cable Television Relay Service to serve cable television systems and other eligible systems, shall contain the condition that cable television... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES CABLE TELEVISION RELAY...

  2. 47 CFR 78.27 - License conditions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., modifications, assignments or transfers of control, and renewals) in the Cable Television Relay Service to serve cable television systems and other eligible systems, shall contain the condition that cable television... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES CABLE TELEVISION RELAY...

  3. Prescription and over-the-counter medications tool kit.

    DOT National Transportation Integrated Search

    2011-04-01

    Automatic vehicle location (AVL) is a computer-based vehicle tracking system. For transit, the actual real-time position of each vehicle is measured and its location is relayed to a control center. Actual position determination and relay techniques v...

  4. Electronic circuit provides accurate sensing and control of dc voltage

    NASA Technical Reports Server (NTRS)

    Loftus, W. D.

    1966-01-01

    Electronic circuit used relay coil to sense and control dc voltage. The control relay is driven by a switching transistor that is biased to cutoff for all input up to slightly less than the threshold level.

  5. Closed Genome Sequence of Chryseobacterium piperi Strain CTMT/ATCC BAA-1782, a Gram-Negative Bacterium with Clostridial Neurotoxin-Like Coding Sequences

    PubMed Central

    Wentz, Travis G.; Muruvanda, Tim; Thirunavukkarasu, Nagarajan; Hoffmann, Maria; Allard, Marc W.; Hodge, David R.; Pillai, Segaran P.; Hammack, Thomas S.; Brown, Eric W.

    2017-01-01

    ABSTRACT Clostridial neurotoxins, including botulinum and tetanus neurotoxins, are among the deadliest known bacterial toxins. Until recently, the horizontal mobility of this toxin gene family appeared to be limited to the genus Clostridium. We report here the closed genome sequence of Chryseobacterium piperi, a Gram-negative bacterium containing coding sequences with homology to clostridial neurotoxin family proteins. PMID:29192076

  6. 8. North elevation of electric relay station showing electrical cable ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. North elevation of electric relay station showing electrical cable connection to tower. - New York, New Haven, & Hartford Railroad, Shell Interlocking Tower, New Haven Milepost 16, approximately 100 feel east of New Rochelle Junction, New Rochelle, Westchester County, NY

  7. 129. INTERIOR OF RELAY BOX FOR HYDRAULIC CONTROL PANEL IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    129. INTERIOR OF RELAY BOX FOR HYDRAULIC CONTROL PANEL IN UMBILICAL MAST PUMP ROOM (209), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  8. 43 CFR 2806.43 - How does BLM calculate rent for passive reflectors and local exchange networks?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MANAGEMENT (2000) RIGHTS-OF-WAY UNDER THE FEDERAL LAND POLICY MANAGEMENT ACT Rents Communication Site Rights... used to bend or ricochet electronic signals between active relay stations or between an active relay...

  9. 43 CFR 2806.43 - How does BLM calculate rent for passive reflectors and local exchange networks?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MANAGEMENT (2000) RIGHTS-OF-WAY UNDER THE FEDERAL LAND POLICY MANAGEMENT ACT Rents Communication Site Rights... used to bend or ricochet electronic signals between active relay stations or between an active relay...

  10. 43 CFR 2806.43 - How does BLM calculate rent for passive reflectors and local exchange networks?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MANAGEMENT (2000) RIGHTS-OF-WAY UNDER THE FEDERAL LAND POLICY MANAGEMENT ACT Rents Communication Site Rights... used to bend or ricochet electronic signals between active relay stations or between an active relay...

  11. 78 FR 28633 - TE Connectivity, a Subsidiary of Tyco Electronics Corporation, Relay Products Business Unit...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-15

    ... transformers. The notice was published in the Federal Register on April 1, 2013 (78 FR 19532). At the request... electromechanical relays, contactors and transformers to a foreign country. Based on these findings, the Department...

  12. Internet Relay Chat.

    ERIC Educational Resources Information Center

    Simpson, Carol

    2000-01-01

    Describes Internet Relay Chats (IRCs), electronic conversations over the Internet that allow multiple users to write messages, and their applications to educational settings such as teacher collaboration and conversations between classes. Explains hardware and software requirements, IRC organization into nets and channels, and benefits and…

  13. Image Relayed by MAVEN Mars Orbiter from Curiosity Mars Rover

    NASA Image and Video Library

    2014-11-10

    The first demonstration of NASA MAVEN Mars orbiter capability to relay data from a Mars surface mission, on Nov. 6, 2014, included this image, taken Oct. 23, 2014, by Curiosity Navigation Camera, showing part of Pahrump Hills outcrop.

  14. 76 FR 58103 - Privacy Act of 1974; Implementation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ... investigations and relay law enforcement information without compromise of the information, protect investigative... confidence. The exemption will allow DoD to provide protection against notification of investigatory material... certain investigations and relay law enforcement information without compromise of the information...

  15. 78 FR 44475 - Protection System Maintenance Reliability Standard

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... Protection System Maintenance--Phase 2 (Reclosing Relays)). 12. NERC states that the proposed Reliability... of the relay inputs and outputs that are essential to proper functioning of the protection system...] Protection System Maintenance Reliability Standard AGENCY: Federal Energy Regulatory Commission, Energy...

  16. 77 FR 15588 - Privacy Act of 1974; Implementation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-16

    ... investigations and relay law enforcement information without compromise of the information, protect investigative... confidence. The exemption will allow DoD to provide protection against notification of investigatory material... certain investigations and relay law enforcement information without compromise of the information...

  17. Using Software Zelio Soft in Educational Process to Simulation Control Programs for Intelligent Relays

    NASA Astrophysics Data System (ADS)

    Michalik, Peter; Mital, Dusan; Zajac, Jozef; Brezikova, Katarina; Duplak, Jan; Hatala, Michal; Radchenko, Svetlana

    2016-10-01

    Article deals with point to using intelligent relay and PLC systems in practice, to their architecture and principles of programming and simulations for education process on all types of school from secondary to universities. Aim of the article is proposal of simple examples of applications, where is demonstrated methodology of programming on real simple practice examples and shown using of chosen instructions. In practical part is described process of creating schemas and describing of function blocks, where are described methodologies of creating program and simulations of output reactions on changeable inputs for intelligent relays.

  18. Satellite data relay and platform locating in oceanography. Report of the In Situ Ocean Science Working Group

    NASA Technical Reports Server (NTRS)

    Chase, R.; Cote, C.; Davis, R. E.; Dugan, J.; Frame, D. D.; Halpern, D.; Kerut, E.; Kirk, R.; Mcgoldrick, L.; Mcwilliams, J. C.

    1983-01-01

    The present and future use of satellites to locate offshore platforms and relay data from in situ sensors to shore was examined. A system of the ARGOS type will satisfy the increasing demand for oceanographic information through data relay and platform location. The improved ship navigation provided by the Global Positioning System (GPS) will allow direct observation of currents from underway ships. Ocean systems are described and demand estimates on satellite systems are determined. The capabilities of the ARGOS system is assessed, including anticipated demand in the next decade.

  19. Overview and Status of the Laser Communication Relay Demonstration

    NASA Technical Reports Server (NTRS)

    Luzhanskiy, E.; Edwards, B.; Israel, D.; Cornwell, D.; Staren, J.; Cummings, N.; Roberts, T.; Patschke, R.

    2016-01-01

    NASA is presently developing first all optical high data rate satellite relay system, LCRD. To be flown on commercial geosynchronous satellite, it will communicate at DPSK and PPM modulation formats up to 1.244 Gbps. LCRD flight payload is being developed by NASA's Goddard Space Flight Center. The two ground stations, one on Table Mountain in CA, developed by NASA's Jet Propulsion Laboratory and another on Hawaiian island will enable bi-directional relay operation and ground sites diversity experiments. In this paper we will report on the current state of LCRD system development, planned operational scenarios and expected system performance.

  20. A fluorescein-based chemosensor for relay fluorescence recognition of Cu(ii) ions and biothiols in water and its applications to a molecular logic gate and living cell imaging.

    PubMed

    Fu, Zhen-Hai; Yan, Lu-Bin; Zhang, Xiaolong; Zhu, Fan-Fan; Han, Xin-Long; Fang, Jianguo; Wang, Ya-Wen; Peng, Yu

    2017-05-16

    Relay recognition of copper(ii) ions and biothiols via a fluorescence "on-off-on" cascade was designed and realized as a new sequential combination of cations and small molecules. Probe 1 bearing a fluorescein skeleton was thus synthesized, which performed well in 100% HEPES buffer (pH = 7.0) solution, as a highly sensitive, selective fluorescence sensor for Cu 2+ . The limit of detection (LOD, 0.017 ppm) was obtained, and this value is much lower than 1.3 ppm, allowed by US EPA. The 1 : 1 complex generated from fast sensing of Cu 2+ when excited at 491 nm, showed good relay recognition for biothiols (i.e., Cys, Hcy and GSH with low detection limits of 0.12 μM, 0.036 μM and 0.024 μM, respectively) via remarkable fluorescence enhancement. The origin of this relay process was disclosed through ESI-MS and corresponding density functional theory (DFT) computations. Notably, probe 1 can be utilized for the construction of a molecular logic gate with the IMPLICATION function by using the above fluorescence changes. Moreover, this relay recognition was also applied to HepG2 cell imaging successfully.

  1. Protection Relaying Scheme Based on Fault Reactance Operation Type

    NASA Astrophysics Data System (ADS)

    Tsuji, Kouichi

    The theories of operation of existing relays are roughly divided into two types: one is the current differential types based on Kirchhoff's first law and the other is impedance types based on second law. We can apply the Kirchhoff's laws to strictly formulate fault phenomena, so the circuit equations are represented non linear simultaneous equations with variables fault point k and fault resistance Rf. This method has next two defect. 1) heavy computational burden for the iterative calculation on N-R method, 2) relay operator can not easily understand principle of numerical matrix operation. The new protection relay principles we proposed this paper focuses on the fact that the reactance component on fault point is almost zero. Two reactance Xf(S), Xf(R) on branch both ends are calculated by operation of solving linear equations. If signs of Xf(S) and Xf(R) are not same, it can be judged that the fault point exist in the branch. This reactance Xf corresponds to difference of branch reactance between actual fault point and imaginaly fault point. And so relay engineer can to understand fault location by concept of “distance". The simulation results using this new method indicates the highly precise estimation of fault locations compared with the inspected fault locations on operating transmission lines.

  2. Outage analysis of relay-assisted underwater wireless optical communication systems

    NASA Astrophysics Data System (ADS)

    Tabeshnezhad, Azadeh; Pourmina, Mohammad Ali

    2017-12-01

    In this paper, we theoretically evaluate the outage probabilities of underwater wireless optical communication (UWOC) systems. Our derivations are general as the channel model under consideration takes into account all of the channel degrading effects, namely absorption, scattering, and turbulence-induced fading. We numerically show that the UWOC systems, due to the severe channel impairments, cannot typically support longer link ranges than 100 m. Therefore, in this paper, in order to increase the transmission reliability and hence extend the viable communication range of UWOC systems, we apply decode-and-forward (DF) relay-assisted communications either in the form of multi-hop transmission, where multiple intermediate relays are serially employed between the source and destination, or parallel relaying in which multiple DF relays are distributed among the source-to-destination path to cooperate in the end-to-end transmission. Our numerical results reveal that multi-hop transmission, owing to the distance-dependency of all of the channel degrading effects, can tremendously improve the end-to-end outage probability and increase the accessible link ranges to hundreds of meter. For example, a dual-hop transmission in a 45 m coastal water link can provide up to 41 dB performance improvement at the outage probability of 10-9.

  3. Scheduling algorithm for data relay satellite optical communication based on artificial intelligent optimization

    NASA Astrophysics Data System (ADS)

    Zhao, Wei-hu; Zhao, Jing; Zhao, Shang-hong; Li, Yong-jun; Wang, Xiang; Dong, Yi; Dong, Chen

    2013-08-01

    Optical satellite communication with the advantages of broadband, large capacity and low power consuming broke the bottleneck of the traditional microwave satellite communication. The formation of the Space-based Information System with the technology of high performance optical inter-satellite communication and the realization of global seamless coverage and mobile terminal accessing are the necessary trend of the development of optical satellite communication. Considering the resources, missions and restraints of Data Relay Satellite Optical Communication System, a model of optical communication resources scheduling is established and a scheduling algorithm based on artificial intelligent optimization is put forwarded. According to the multi-relay-satellite, multi-user-satellite, multi-optical-antenna and multi-mission with several priority weights, the resources are scheduled reasonable by the operation: "Ascertain Current Mission Scheduling Time" and "Refresh Latter Mission Time-Window". The priority weight is considered as the parameter of the fitness function and the scheduling project is optimized by the Genetic Algorithm. The simulation scenarios including 3 relay satellites with 6 optical antennas, 12 user satellites and 30 missions, the simulation result reveals that the algorithm obtain satisfactory results in both efficiency and performance and resources scheduling model and the optimization algorithm are suitable in multi-relay-satellite, multi-user-satellite, and multi-optical-antenna recourses scheduling problem.

  4. Communications Relay and Human-Assisted Sample Return from the Deep Space Gateway

    NASA Astrophysics Data System (ADS)

    Cichan, T.; Hopkins, J. B.; Bierhaus, B.; Murrow, D. W.

    2018-02-01

    The Deep Space Gateway can enable or enhance exploration of the lunar surface through two capabilities: 1. communications relay, opening up access to the lunar farside, and 2. sample return, enhancing the ability to return large sample masses.

  5. First Things First: Internet Relay Chat Openings.

    ERIC Educational Resources Information Center

    Rintel, E. Sean; Mulholland, Joan; Pittam, Jeffery

    2001-01-01

    Argues that Internet Relay Chat (IRC) research needs to systematically address links between interaction structures, technological mediation and the instantiation and development of interpersonal relationships. Finds that openings that occur directly following user's entries into public IRC channels are often ambiguous, can disrupt relationship…

  6. A multi-sensor RSS spatial sensing-based robust stochastic optimization algorithm for enhanced wireless tethering.

    PubMed

    Parasuraman, Ramviyas; Fabry, Thomas; Molinari, Luca; Kershaw, Keith; Di Castro, Mario; Masi, Alessandro; Ferre, Manuel

    2014-12-12

    The reliability of wireless communication in a network of mobile wireless robot nodes depends on the received radio signal strength (RSS). When the robot nodes are deployed in hostile environments with ionizing radiations (such as in some scientific facilities), there is a possibility that some electronic components may fail randomly (due to radiation effects), which causes problems in wireless connectivity. The objective of this paper is to maximize robot mission capabilities by maximizing the wireless network capacity and to reduce the risk of communication failure. Thus, in this paper, we consider a multi-node wireless tethering structure called the "server-relay-client" framework that uses (multiple) relay nodes in between a server and a client node. We propose a robust stochastic optimization (RSO) algorithm using a multi-sensor-based RSS sampling method at the relay nodes to efficiently improve and balance the RSS between the source and client nodes to improve the network capacity and to provide redundant networking abilities. We use pre-processing techniques, such as exponential moving averaging and spatial averaging filters on the RSS data for smoothing. We apply a receiver spatial diversity concept and employ a position controller on the relay node using a stochastic gradient ascent method for self-positioning the relay node to achieve the RSS balancing task. The effectiveness of the proposed solution is validated by extensive simulations and field experiments in CERN facilities. For the field trials, we used a youBot mobile robot platform as the relay node, and two stand-alone Raspberry Pi computers as the client and server nodes. The algorithm has been proven to be robust to noise in the radio signals and to work effectively even under non-line-of-sight conditions.

  7. A Multi-Sensor RSS Spatial Sensing-Based Robust Stochastic Optimization Algorithm for Enhanced Wireless Tethering

    PubMed Central

    Parasuraman, Ramviyas; Fabry, Thomas; Molinari, Luca; Kershaw, Keith; Di Castro, Mario; Masi, Alessandro; Ferre, Manuel

    2014-01-01

    The reliability of wireless communication in a network of mobile wireless robot nodes depends on the received radio signal strength (RSS). When the robot nodes are deployed in hostile environments with ionizing radiations (such as in some scientific facilities), there is a possibility that some electronic components may fail randomly (due to radiation effects), which causes problems in wireless connectivity. The objective of this paper is to maximize robot mission capabilities by maximizing the wireless network capacity and to reduce the risk of communication failure. Thus, in this paper, we consider a multi-node wireless tethering structure called the “server-relay-client” framework that uses (multiple) relay nodes in between a server and a client node. We propose a robust stochastic optimization (RSO) algorithm using a multi-sensor-based RSS sampling method at the relay nodes to efficiently improve and balance the RSS between the source and client nodes to improve the network capacity and to provide redundant networking abilities. We use pre-processing techniques, such as exponential moving averaging and spatial averaging filters on the RSS data for smoothing. We apply a receiver spatial diversity concept and employ a position controller on the relay node using a stochastic gradient ascent method for self-positioning the relay node to achieve the RSS balancing task. The effectiveness of the proposed solution is validated by extensive simulations and field experiments in CERN facilities. For the field trials, we used a youBot mobile robot platform as the relay node, and two stand-alone Raspberry Pi computers as the client and server nodes. The algorithm has been proven to be robust to noise in the radio signals and to work effectively even under non-line-of-sight conditions. PMID:25615734

  8. What Is a False Negative Sentinel Node Biopsy: Definition, Reasons and Ways to Minimize It?

    PubMed

    Kataria, Kamal; Srivastava, Anurag; Qaiser, Darakhshan

    2016-10-01

    Sentinel node biopsy helps in assessing the involvement of axillary lymph node without the morbidity of full axillary lymph node dissection, namely arm and shoulder pain, paraesthesia and lymphoedema. The various methods described in the literature identify the sentinel lymph nodes in approximately 96 % of cases and associated with a false negativity rate of 5 to 10 %. A false negative sentinel node is defined as the proportion of cases in whom sentinel node biopsy is reported as negative, but the rest of axillary lymph node(s) harbours cancer cells. The possible causes of a false negative sentinel lymph node may be because of blocked lymphatics either by cancer cells or following fibrosis of previous surgery/radiotherapy, and an alternative pathway opens draining the blue dye or isotope to another uninvolved node . The other reasons may be two lymphatic pathways for a tumour area, the one opening to a superficial node and the other in deep nodes. Sometimes, lymphatics do not relay into a node but traverse it going to a higher node. In some patients, the microscopic focus of metastasis inside a lymph node is so small-micrometastasis (i.e. between 0.2 and 2 mm) or isolated tumour cells (i.e. less than 0.2 mm) that is missed by the pathologist. The purpose of this review is to clear some fears lurking in the mind of most surgeons about the false negative sentinel lymph node (FNSLN).

  9. Design Concepts for a Small Space-Based GEO Relay Satellite for Missions Between Low Earth and near Earth Orbits

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul B.; Warner, Joseph D.; Oleson, Steven; Schier, James

    2014-01-01

    The main purpose of the Small Space-Based Geosynchronous Earth orbiting (GEO) satellite is to provide a space link to the user mission spacecraft for relaying data through ground networks to user Mission Control Centers. The Small Space Based Satellite (SSBS) will provide services comparable to those of a NASA Tracking Data Relay Satellite (TDRS) for the same type of links. The SSBS services will keep the user burden the same or lower than for TDRS and will support the same or higher data rates than those currently supported by TDRS. At present, TDRSS provides links and coverage below GEO; however, SSBS links and coverage capability to above GEO missions are being considered for the future, especially for Human Space Flight Missions (HSF). There is also a rising need for the capability to support high data rate links (exceeding 1 Gbps) for imaging applications. The communication payload on the SSBS will provide S/Ka-band single access links to the mission and a Ku-band link to the ground, with an optical communication payload as an option. To design the communication payload, various link budgets were analyzed and many possible operational scenarios examined. To reduce user burden, using a larger-sized antenna than is currently in use by TDRS was considered. Because of the SSBS design size, it was found that a SpaceX Falcon 9 rocket could deliver three SSBSs to GEO. This will greatly reduce the launch costs per satellite. Using electric propulsion was also evaluated versus using chemical propulsion; the power system size and time to orbit for various power systems were also considered. This paper will describe how the SSBS will meet future service requirements, concept of operations, and the design to meet NASA users' needs for below and above GEO missions. These users' needs not only address the observational mission requirements but also possible HSF missions to the year 2030. We will provide the trade-off analysis of the communication payload design in terms of the number of links looking above and below GEO; the detailed design of a GEO SSBS spacecraft bus and its accommodation of the communication payload, and a summary of the trade study that resulted in the selection of the Falcon 9 launch vehicle to deploy the SSBS and its impact on cost reductions per satellite. ======================================================================== Several initiatives have taken place within NASA1 and international space agencies2 to create a human exploration strategy for expanding human presence into the solar system; these initiatives have been driven by multiple factors to benefit Earth. Of the many elements in the strategy one stands out: to send robotic and human missions to destinations beyond Low Earth Orbit (LEO), including cis-lunar space, Near-Earth Asteroids (NEAs), the Moon, and Mars and its moons.3, 4 The time frame for human exploration to various destinations, based on the public information available,1,4 is shown in Figure 1. Advance planning is needed to define how future space communications services will be provided in the new budget environment to meet future space communications needs. The spacecraft for these missions can be dispersed anywhere from below LEO to beyond GEO, and to various destinations within the solar system. NASA's Space Communications and Navigation (SCaN) program office provides communication and tracking services to space missions during launch, in-orbit testing, and operation phases. Currently, SCaN's space networking relay satellites mainly provide services to users below GEO, at Near Earth Orbit (NEO), below LEO, and in deep space. The potential exists for using a space-based relay satellite, located in the vicinity of various solar system destinations, to provide communication space links to missions both below and above its orbit. Such relays can meet the needs of human exploration missions for maximum connectivity to Earth locations and for reduced latency. In the past, several studies assessed the ability of satellite-based relays working above GEO in conjunction with Earth ground stations. Many of these focused on the trade between space relay and direct-to-Earth station links5,6,7. Several others focused on top-level architecture based on relays at various destinations8,9,10,11,12. Much has changed in terms of microwave and optical technology since the publication of the referenced papers; Ka-band communication systems are being deployed, optical communication is being demonstrated, and spacecraft buses are becoming increasingly more functional and operational. A design concept study was undertaken to access the potential for deploying a Small Space-Based Satellite (SSBS) relay capable of serving missions between LEO and NEO. The needs of future human exploration missions were analyzed, and a notional relay-based architecture concept was generated as shown in Fig. 1. Relay satellites in Earth through cis-Lunar orbits are normally located in stable orbits requiring low fuel consumption. Relay satellites for Mars orbit are normally selected based on the mission requirement and projected fuel consumption. Relay satellites have extreme commonalities of functions between them, differing only in the redundancy and frequencies used; therefore, the relay satellite in GEO was selected for further analysis since it will be the first step in achieving a relay-based architecture for human exploration missions (see Fig.Figure 2). The mission design methodology developed by the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team13 was used to produce the satellite relay design and to perform various design trades. At the start of the activity, the team was provided with the detailed concept of the notional architecture and the system and communication payload drivers.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fogh, R.H.; Mabbutt, B.C.; Kem, W.R.

    Sequence-specific assignments are reported for the 500-MHz H nuclear magnetic resonance (NMR) spectrum of the 48-residue polypeptide neurotoxin I from the sea anemone Stichodactyla helianthus (Sh I). Spin systems were first identified by using two-dimensional relayed or multiple quantum filtered correlation spectroscopy, double quantum spectroscopy, and spin lock experiments. Specific resonance assignments were then obtained from nuclear Overhauser enhancement (NOE) connectivities between protons from residues adjacent in the amino acid sequence. Of a total of 265 potentially observable resonances, 248 (i.e., 94%) were assigned, arising from 39 completely and 9 partially assigned amino acid spin systems. The secondary structure ofmore » Sh I was defined on the basis of the pattern of sequential NOE connectivities. NOEs between protons on separate strands of the polypeptide backbone, and backbone amide exchange rates. Sh I contains a four-stranded antiparallel {beta}-sheet encompassing residues 1-5, 16-24, 30-33, and 40-46, with a {beta}-bulge at residues 17 and 18 and a reverse turn, probably a type II {beta}-turn, involving residues 27-30. No evidence of {alpha}-helical structure was found.« less

  11. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    KOCH, M.R.; JOHNS, B.R.

    1999-12-21

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  12. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    KOCH, M.R.

    2000-02-28

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping Instrumentation and Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  13. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    KOCH, M.R.

    1999-08-11

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  14. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    JOHNS, B.R.

    1999-05-05

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  15. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    KOCH, M.R.

    1999-10-26

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  16. Commercial Grade Item (CGI) Dedication for Leak Detection Relays

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    JOHNS, B.R.; KOCH, M.R.

    2000-01-28

    This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping Instrumentation and Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis.

  17. 47 CFR 74.635 - Unattended operation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... stations, and TV microwave booster stations may be operated unattended under the following conditions: (1... persons; (3) TV relay stations, TV STL stations, TV translator relay stations, and TV microwave booster..., an STL station (and any TV microwave booster station) associated with a TV broadcast station operated...

  18. 47 CFR 74.635 - Unattended operation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... stations, and TV microwave booster stations may be operated unattended under the following conditions: (1... persons; (3) TV relay stations, TV STL stations, TV translator relay stations, and TV microwave booster..., an STL station (and any TV microwave booster station) associated with a TV broadcast station operated...

  19. 47 CFR 74.635 - Unattended operation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... stations, and TV microwave booster stations may be operated unattended under the following conditions: (1... persons; (3) TV relay stations, TV STL stations, TV translator relay stations, and TV microwave booster..., an STL station (and any TV microwave booster station) associated with a TV broadcast station operated...

  20. 47 CFR 74.635 - Unattended operation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... stations, and TV microwave booster stations may be operated unattended under the following conditions: (1... persons; (3) TV relay stations, TV STL stations, TV translator relay stations, and TV microwave booster..., an STL station (and any TV microwave booster station) associated with a TV broadcast station operated...

  1. Mars Telecom Orbiter mission operations concepts

    NASA Technical Reports Server (NTRS)

    Deutsch, Marie-Jose; Komarek, Tom; Lopez, Saturnino; Townes, Steve; Synnott, Steve; Austin, Richard; Guinn, Joe; Varghese, Phil; Edwards, Bernard; Bondurant, Roy; hide

    2004-01-01

    The Mars Telecom Orbiter (MTO) relay capability enables next decadal missions at Mars, collecting gigabits of data a day to be relayed back at speeds exceeding 4 Mbps and it facilitates small missions whose limited resources do not permit them to have a direct link to Earth.

  2. 76 FR 24437 - Structure and Practices of the Video Relay Service Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... applicant, a description of the applicant's organizational structure, including the names of its executives... Internet-based relay service, including documentation on loans for equipment, inventory, property... over the applicant, a description of the applicant's organizational structure, and the names of its...

  3. Proper development of relay somatic sensory neurons and D2/D4 interneurons requires homeobox genes Rnx/Tlx-3 and Tlx-1

    PubMed Central

    Qian, Ying; Shirasawa, Senji; Chen, Chih-Li; Cheng, Leping; Ma, Qiufu

    2002-01-01

    Trigeminal nuclei and the dorsal spinal cord are first-order relay stations for processing somatic sensory information such as touch, pain, and temperature. The origins and development of these neurons are poorly understood. Here we show that relay somatic sensory neurons and D2/D4 dorsal interneurons likely derive from Mash1-positive neural precursors, and depend on two related homeobox genes, Rnx and Tlx-1, for proper formation. Rnx and Tlx-1 maintain expression of Drg11, a homeobox gene critical for the development of pain circuitry, and are essential for the ingrowth of trkA+ nociceptive/thermoceptive sensory afferents to their central targets. We showed previously that Rnx is necessary for proper formation of the nucleus of solitary tract, the target for visceral sensory afferents. Together, our studies demonstrate a central role for Rnx and Tlx-1 in the development of two major classes of relay sensory neurons, somatic and visceral. PMID:12023301

  4. Proper development of relay somatic sensory neurons and D2/D4 interneurons requires homeobox genes Rnx/Tlx-3 and Tlx-1.

    PubMed

    Qian, Ying; Shirasawa, Senji; Chen, Chih-Li; Cheng, Leping; Ma, Qiufu

    2002-05-15

    Trigeminal nuclei and the dorsal spinal cord are first-order relay stations for processing somatic sensory information such as touch, pain, and temperature. The origins and development of these neurons are poorly understood. Here we show that relay somatic sensory neurons and D2/D4 dorsal interneurons likely derive from Mash1-positive neural precursors, and depend on two related homeobox genes, Rnx and Tlx-1, for proper formation. Rnx and Tlx-1 maintain expression of Drg11, a homeobox gene critical for the development of pain circuitry, and are essential for the ingrowth of trkA+ nociceptive/thermoceptive sensory afferents to their central targets. We showed previously that Rnx is necessary for proper formation of the nucleus of solitary tract, the target for visceral sensory afferents. Together, our studies demonstrate a central role for Rnx and Tlx-1 in the development of two major classes of relay sensory neurons, somatic and visceral.

  5. Intelligent Power Swing Detection Scheme to Prevent False Relay Tripping Using S-Transform

    NASA Astrophysics Data System (ADS)

    Mohamad, Nor Z.; Abidin, Ahmad F.; Musirin, Ismail

    2014-06-01

    Distance relay design is equipped with out-of-step tripping scheme to ensure correct distance relay operation during power swing. The out-of-step condition is a consequence result from unstable power swing. It requires proper detection of power swing to initiate a tripping signal followed by separation of unstable part from the entire power system. The distinguishing process of unstable swing from stable swing poses a challenging task. This paper presents an intelligent approach to detect power swing based on S-Transform signal processing tool. The proposed scheme is based on the use of S-Transform feature of active power at the distance relay measurement point. It is demonstrated that the proposed scheme is able to detect and discriminate the unstable swing from stable swing occurring in the system. To ascertain validity of the proposed scheme, simulations were carried out with the IEEE 39 bus system and its performance has been compared with the wavelet transform-based power swing detection scheme.

  6. Ground wave emergency network final operational capability: Environmental assessment for northwestern Nebraska relay node, site number RN 8C930NE

    NASA Astrophysics Data System (ADS)

    1993-02-01

    The Ground Wave Emergency Network (GWEN) is a radio communication system designed to relay emergency messages between strategic military areas in the continental United States. The system is immune to the effects of high-altitude electromagnetic pulse (HEMP) energy surges caused by nuclear bursts in the ionosphere that would disrupt conventional communications equipment such as telephones and shortwave radios. A failure of such equipment would prevent timely communications among top military and civilian leaders and strategic Air Force locations and prevent U.S. assessment and retaliation during an attack. GWEN is an essential part of a defense modernization program to upgrade and improve our nation's communications system, thereby strengthening deterrence. The GWEN system consists of a network of relay nodes, receive-only stations, and input/output stations. Each relay node, such as the one proposed in northwestern Nebraska, consists of a guyed radio tower facility similar to those used by commercial AM broadcast transmitters.

  7. Ground wave emergency network environmental assessment for northwestern Colorado relay node site number RN 8C924CO

    NASA Astrophysics Data System (ADS)

    1993-02-01

    The Ground Wave Emergency Network (GWEN) is a radio communication system designed to relay emergency messages between strategic military areas in the continental United States. The system is immune to the effects of high-altitude electromagnetic pulse (HEMP) energy surges caused by nuclear bursts in the ionosphere that would disrupt conventional communications equipment such as telephones and shortwave radios. A failure of such equipment would prevent timely communications among top military and civilian leaders and strategic Air Force locations and prevent U.S. assessment and retaliation during an attack. GWEN is an essential part of a defense modernization program to upgrade and improve our nation's communications system, thereby strengthening deterrence. The GWEN system consists of a network of relay nodes, receive-only stations, and input/output stations. Each relay node, such as the one proposed in southern Nevada consists of a guyed radio tower facility similar to those used by commercial AM broadcast transmitters.

  8. Ground wave emergency network final operational capability: Environmental assessment for southern Nevada relay node site number RN 8W918NV

    NASA Astrophysics Data System (ADS)

    1993-03-01

    The Ground Wave Emergency Network (GWEN) is a radio communication system designed to relay emergency messages between strategic military areas in the continental United States. The system is immune to the effects of high-altitude electromagnetic pulse (HEMP) energy surges caused by nuclear bursts in the ionosphere that would disrupt conventional communications equipment such as telephones and shortwave radios. A failure of such equipment would prevent timely communications among top military and civilian leaders and strategic Air Force locations and prevent U.S. assessment and retaliation during an attack. GWEN is an essential part of a defense modernization program to upgrade and improve our nation's communications system, thereby strengthening deterrence. The GWEN system consists of a network of relay nodes, receive-only stations, and input/output stations. Each relay node, such as the one proposed in southern Nevada consists of a guyed radio tower facility similar to those used by commercial AM broadcast transmitters.

  9. Solid state power controllers

    NASA Technical Reports Server (NTRS)

    Gibbs, R. S.

    1974-01-01

    Solid state power controllers (SSPC's) are to be considered for use as replacements of electromechanical relays and circuit breakers in future spacecraft and aircraft. They satisfy the combined function of both the relay and circuit breaker and can be remotely controlled by small signals, typically 10 mA, 5 to 28 v(dc). They have the advantage over conventional relay/circuit breaker systems in that they can be located near the utilization equipment and the primary ac or dc bus. The low level control, trip indication and status signals can be circuited by small gauge wire for control, computer interface, logic, electrical multiplexing, onboard testing, power management, and distribution purposes. This results in increased system versatility at appreciable weight saving and increased reliability. Conventional systems require the heavy gage load wiring and the control wiring to be routed from the bus to the load to other remote relay contacts, switches, sensors, etc. and to the circuit breaker located in the flight engineer's compartment for purposes of manual reset.

  10. A bioinspired redox relay that mimics radical interactions of the Tyr-His pairs of photosystem II

    NASA Astrophysics Data System (ADS)

    Megiatto, Jackson D., Jr.; Méndez-Hernández, Dalvin D.; Tejeda-Ferrari, Marely E.; Teillout, Anne-Lucie; Llansola-Portolés, Manuel J.; Kodis, Gerdenis; Poluektov, Oleg G.; Rajh, Tijana; Mujica, Vladimiro; Groy, Thomas L.; Gust, Devens; Moore, Thomas A.; Moore, Ana L.

    2014-05-01

    In water-oxidizing photosynthetic organisms, light absorption generates a powerfully oxidizing chlorophyll complex (P680•+) in the photosystem II reaction centre. This is reduced via an electron transfer pathway from the manganese-containing water-oxidizing catalyst, which includes an electron transfer relay comprising a tyrosine (Tyr)-histidine (His) pair that features a hydrogen bond between a phenol group and an imidazole group. By rapidly reducing P680•+, the relay is thought to mitigate recombination reactions, thereby ensuring a high quantum yield of water oxidation. Here, we show that an artificial reaction centre that features a benzimidazole-phenol model of the Tyr-His pair mimics both the short-internal hydrogen bond in photosystem II and, using electron paramagnetic resonance spectroscopy, the thermal relaxation that accompanies proton-coupled electron transfer. Although this artificial system is much less complex than the natural one, theory suggests that it captures the essential features that are important in the function of the relay.

  11. Joint Resource Optimization for Cognitive Sensor Networks with SWIPT-Enabled Relay.

    PubMed

    Lu, Weidang; Lin, Yuanrong; Peng, Hong; Nan, Tian; Liu, Xin

    2017-09-13

    Energy-constrained wireless networks, such as wireless sensor networks (WSNs), are usually powered by fixed energy supplies (e.g., batteries), which limits the operation time of networks. Simultaneous wireless information and power transfer (SWIPT) is a promising technique to prolong the lifetime of energy-constrained wireless networks. This paper investigates the performance of an underlay cognitive sensor network (CSN) with SWIPT-enabled relay node. In the CSN, the amplify-and-forward (AF) relay sensor node harvests energy from the ambient radio-frequency (RF) signals using power splitting-based relaying (PSR) protocol. Then, it helps forward the signal of source sensor node (SSN) to the destination sensor node (DSN) by using the harvested energy. We study the joint resource optimization including the transmit power and power splitting ratio to maximize CSN's achievable rate with the constraint that the interference caused by the CSN to the primary users (PUs) is within the permissible threshold. Simulation results show that the performance of our proposed joint resource optimization can be significantly improved.

  12. Network Coding in Relay-based Device-to-Device Communications

    PubMed Central

    Huang, Jun; Gharavi, Hamid; Yan, Huifang; Xing, Cong-cong

    2018-01-01

    Device-to-Device (D2D) communications has been realized as an effective means to improve network throughput, reduce transmission latency, and extend cellular coverage in 5G systems. Network coding is a well-established technique known for its capability to reduce the number of retransmissions. In this article, we review state-of-the-art network coding in relay-based D2D communications, in terms of application scenarios and network coding techniques. We then apply two representative network coding techniques to dual-hop D2D communications and present an efficient relay node selecting mechanism as a case study. We also outline potential future research directions, according to the current research challenges. Our intention is to provide researchers and practitioners with a comprehensive overview of the current research status in this area and hope that this article may motivate more researchers to participate in developing network coding techniques for different relay-based D2D communications scenarios. PMID:29503504

  13. Event-Related Potentials Elicited by Pre-Attentive Emotional Changes in Temporal Context

    PubMed Central

    Fujimura, Tomomi; Okanoya, Kazuo

    2013-01-01

    The ability to detect emotional change in the environment is essential for adaptive behavior. The current study investigated whether event-related potentials (ERPs) can reflect emotional change in a visual sequence. To assess pre-attentive processing, we examined visual mismatch negativity (vMMN): the negative potentials elicited by a deviant (infrequent) stimulus embedded in a sequence of standard (frequent) stimuli. Participants in two experiments pre-attentively viewed visual sequences of Japanese kanji with different emotional connotations while ERPs were recorded. The visual sequence in Experiment 1 consisted of neutral standards and two types of emotional deviants with a strong and weak intensity. Although the results indicated that strongly emotional deviants elicited more occipital negativity than neutral standards, it was unclear whether these negativities were derived from emotional deviation in the sequence or from the emotional significance of the deviants themselves. In Experiment 2, the two identical emotional deviants were presented against different emotional standards. One type of deviants was emotionally incongruent with the standard and the other type of deviants was emotionally congruent with the standard. The results indicated that occipital negativities elicited by deviants resulted from perceptual changes in a visual sequence at a latency of 100–200 ms and from emotional changes at latencies of 200–260 ms. Contrary to the results of the ERP experiment, reaction times to deviants showed no effect of emotional context; negative stimuli were consistently detected more rapidly than were positive stimuli. Taken together, the results suggest that brain signals can reflect emotional change in a temporal context. PMID:23671693

  14. Event-related potentials elicited by pre-attentive emotional changes in temporal context.

    PubMed

    Fujimura, Tomomi; Okanoya, Kazuo

    2013-01-01

    The ability to detect emotional change in the environment is essential for adaptive behavior. The current study investigated whether event-related potentials (ERPs) can reflect emotional change in a visual sequence. To assess pre-attentive processing, we examined visual mismatch negativity (vMMN): the negative potentials elicited by a deviant (infrequent) stimulus embedded in a sequence of standard (frequent) stimuli. Participants in two experiments pre-attentively viewed visual sequences of Japanese kanji with different emotional connotations while ERPs were recorded. The visual sequence in Experiment 1 consisted of neutral standards and two types of emotional deviants with a strong and weak intensity. Although the results indicated that strongly emotional deviants elicited more occipital negativity than neutral standards, it was unclear whether these negativities were derived from emotional deviation in the sequence or from the emotional significance of the deviants themselves. In Experiment 2, the two identical emotional deviants were presented against different emotional standards. One type of deviants was emotionally incongruent with the standard and the other type of deviants was emotionally congruent with the standard. The results indicated that occipital negativities elicited by deviants resulted from perceptual changes in a visual sequence at a latency of 100-200 ms and from emotional changes at latencies of 200-260 ms. Contrary to the results of the ERP experiment, reaction times to deviants showed no effect of emotional context; negative stimuli were consistently detected more rapidly than were positive stimuli. Taken together, the results suggest that brain signals can reflect emotional change in a temporal context.

  15. [Effects of reduced N application rate on yield and nutrient uptake and utilization in maize-soybean relay strip intercropping system].

    PubMed

    Yong, Tai-Wen; Liu, Xiao-Ming; Wen-Yu, Liu; Su, Ben-Ying; Song, Chun; Yang, Feng; Wang, Xiao-Chun; Yang, Wen-Yu

    2014-02-01

    A field experiment with three N application rates (0, 180, 240 N kg x hm(-2), representing zero, reduced and conventional N application, respectively) and three planting patterns (maize monoculture, soybean monoculture and maize-soybean relay strip intercropping) was conducted to reveal the effects of cropping patterns and N application rates on yield, nutrient uptake and nitrogen use efficiency of maize and soybean. The results showed that the grain yield, N, P and K uptake and harvest index of the intercropped maize reduced slightly compared with the monoculture maize, however these indices of the intercropped soybean increased significantly compared with the monoculture. With the increase in nitrogen fertilizer application, the excellence of relay strip intercropping was weakened in the maize-soybean intercropping system. The grain yield, economic coefficient, N, P and K uptake, harvest index, N agronomy efficiency and N uptake efficiency of maize and soybean increased significantly at the reduced nitrogen rate (180 N kg x hm(-2)), but the rate of soil N contribution declined, compared with the conventional rate of N application by local farmers (240 N kg x hm(-2)). In the reduced nitrogen rate treatment, total soil N and P contents of the maize strip reduced, whereas the total soil N, P and K contents of soybean strip and the total K content of maize strip increased compared with the zero N application treatment. With the reduced N application, the annual total grain yield, N, P and K uptake of above-ground biomass in the maize-soybean relay strip intercropping system were higher than in the monoculture, and the land equivalent ratio (LER) was 2.28. N uptake efficiency of maize in the relay strip intercropping system was 20.2% higher than in the maize monoculture, and the index of soybean was 30.5% lower than in the monoculture. The rate of soil N contribution in the relay strip intercropping system was 20.0% and 8.8% lower than in the maize and soybean monoculture, respectively. The reduced N application in the maize-soybean relay strip intercropping system was helpful to promote annual grain yield and improve N utilization efficiency.

  16. Satellite relay telemetry of seismic data in earthquake prediction and control

    USGS Publications Warehouse

    Jackson, Wayne H.; Eaton, Jerry P.

    1971-01-01

    The Satellite Telemetry Earthquake Monitoring Program was started in FY 1968 to evaluate the applicability of satellite relay telemetry in the collection of seismic data from a large number of dense seismograph clusters laid out along the major fault systems of western North America. Prototype clusters utilizing phone-line telemetry were then being installed by the National Center for Earthquake Research (NCER) in 3 regions along the San Andreas fault in central California; and the experience of installing and operating the clusters and in reducing and analyzing the seismic data from them was to provide the raw materials for evaluation in the satellite relay telemetry project.

  17. Automatic range selector

    DOEpatents

    McNeilly, Clyde E.

    1977-01-04

    A device is provided for automatically selecting from a plurality of ranges of a scale of values to which a meter may be made responsive, that range which encompasses the value of an unknown parameter. A meter relay indicates whether the unknown is of greater or lesser value than the range to which the meter is then responsive. The rotatable part of a stepping relay is rotated in one direction or the other in response to the indication from the meter relay. Various positions of the rotatable part are associated with particular scales. Switching means are sensitive to the position of the rotatable part to couple the associated range to the meter.

  18. Evolving earth-based and in-situ satellite network architectures for Mars communications and navigation support

    NASA Technical Reports Server (NTRS)

    Hastrup, Rolf; Weinberg, Aaron; Mcomber, Robert

    1991-01-01

    Results of on-going studies to develop navigation/telecommunications network concepts to support future robotic and human missions to Mars are presented. The performance and connectivity improvements provided by the relay network will permit use of simpler, lower performance, and less costly telecom subsystems for the in-situ mission exploration elements. Orbiting relay satellites can serve as effective navigation aids by supporting earth-based tracking as well as providing Mars-centered radiometric data for mission elements approaching, in orbit, or on the surface of Mars. The relay satellite orbits may be selected to optimize navigation aid support and communication coverage for specific mission sets.

  19. The magic of relay mirrors

    NASA Astrophysics Data System (ADS)

    Duff, Edward A.; Washburn, Donald C.

    2004-09-01

    Laser weapon systems would be significantly enhanced with the addition of high altitude or space-borne relay mirrors. Such mirrors, operating alone with a directed energy source, or many in a series fashion, can be shown to effectively move the laser source to the last, so-called fighting mirror. This "magically" reduces the range to target and offers to enhance the performance of directed energy systems like the Airborne Laser and even ground-based or ship-based lasers. Recent development of high altitude airships will be shown to provide stationary positions for such relay mirrors thereby enabling many new and important applications for laser weapons. The technical challenges to achieve this capability are discussed.

  20. Evolving earth-based and in-situ satellite network architectures for Mars communications and navigation support

    NASA Astrophysics Data System (ADS)

    Hastrup, Rolf; Weinberg, Aaron; McOmber, Robert

    1991-09-01

    Results of on-going studies to develop navigation/telecommunications network concepts to support future robotic and human missions to Mars are presented. The performance and connectivity improvements provided by the relay network will permit use of simpler, lower performance, and less costly telecom subsystems for the in-situ mission exploration elements. Orbiting relay satellites can serve as effective navigation aids by supporting earth-based tracking as well as providing Mars-centered radiometric data for mission elements approaching, in orbit, or on the surface of Mars. The relay satellite orbits may be selected to optimize navigation aid support and communication coverage for specific mission sets.

  1. The identification of disulfides in ricin D using proteolytic cleavage followed by negative-ion nano-electrospray ionization mass spectrometry of the peptide fragments.

    PubMed

    Tran, T T Nha; Brinkworth, Craig S; Bowie, John H

    2015-01-30

    To use negative-ion nano-electrospray ionization mass spectrometry of peptides from the tryptic digest of ricin D, to provide sequence information; in particular, to identify disulfide position and connectivity. Negative-ion fragmentations of peptides from the tryptic digest of ricin D was studied using a Waters QTOF2 mass spectrometer operating in MS and MS(2) modes. Twenty-three peptides were obtained following high-performance liquid chromatography and studied by negative-ion mass spectrometry covering 73% of the amino-acid residues of ricin D. Five disulfide-containing peptides were identified, three intermolecular and two intramolecular disulfide-containing peptides. The [M-H](-) anions of the intermolecular disulfides undergo facile cleavage of the disulfide units to produce fragment peptides. In negative-ion collision-induced dissociation (CID) these source-formed anions undergo backbone cleavages, which provide sequencing information. The two intramolecular disulfides were converted proteolytically into intermolecular disulfides, which were identified as outlined above. The positions of the five disulfide groups in ricin D may be determined by characteristic negative-ion cleavage of the disulfide groups, while sequence information may be determined using the standard negative-ion backbone cleavages of the resulting cleaved peptides. Negative-ion mass spectrometry can also be used to provide partial sequencing information for other peptides (i.e. those not containing Cys) using the standard negative-ion backbone cleavages of these peptides. Copyright © 2014 John Wiley & Sons, Ltd.

  2. 47 CFR 90.469 - Unattended operation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MOBILE RADIO SERVICES Transmitter Control § 90.469 Unattended operation. (a) Subject to the provisions of §§ 90.243, 90.245, and 90.247, mobile relay, fixed relay, and mobile repeater stations are authorized... where they are activated by either electrical or mechanical devices, provided the licensee adopts...

  3. A scheduling model for the aerial relay system

    NASA Technical Reports Server (NTRS)

    Ausrotas, R. A.; Liu, E. W.

    1980-01-01

    The ability of the Aerial Relay System to handle the U.S. transcontinental large hub passenger flow was analyzed with a flexible, interactive computer model. The model incorporated city pair time of day demand and a demand allocation function which assigned passengers to their preferred flights.

  4. 47 CFR 74.655 - Authorization of equipment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... rules concerning modifications to authorized equipment. (d) Any manufacturer of a transmitter to be used... relay station, a TV translator relay station, or a TV microwave booster station, shall be authorized... Auxiliary Stations § 74.655 Authorization of equipment. (a) Except as provided in paragraph (b) of this...

  5. 47 CFR 74.655 - Authorization of equipment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... rules concerning modifications to authorized equipment. (d) Any manufacturer of a transmitter to be used... relay station, a TV translator relay station, or a TV microwave booster station, shall be authorized... Auxiliary Stations § 74.655 Authorization of equipment. (a) Except as provided in paragraph (b) of this...

  6. 47 CFR 74.655 - Authorization of equipment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... rules concerning modifications to authorized equipment. (d) Any manufacturer of a transmitter to be used... relay station, a TV translator relay station, or a TV microwave booster station, shall be authorized... Auxiliary Stations § 74.655 Authorization of equipment. (a) Except as provided in paragraph (b) of this...

  7. 78 FR 14701 - Misuse of Internet Protocol (IP) Captioned Telephone Service; Telecommunications Relay Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-07

    ...] Misuse of Internet Protocol (IP) Captioned Telephone Service; Telecommunications Relay Services and..., the information collection associated with the Commission's Misuse of Internet Protocol (IP) Captioned... Registration and Documentation of Disability for Eligibility to Use IP Captioned Telephone Service, CG Docket...

  8. 47 CFR 90.243 - Mobile relay stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND... Service. (b) Special provisions for mobile relay operations: (1) In the Public Safety Pool, systems operating on any of the public safety frequencies listed in § 90.20(c) are permitted to be cross-banded for...

  9. 47 CFR 74.537 - Temporary authorizations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

  10. 47 CFR 74.537 - Temporary authorizations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

  11. 47 CFR 74.537 - Temporary authorizations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

  12. 47 CFR 74.632 - Licensing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... home-city users. (e) A license for a TV translator relay station will be issued only to licensees of low power TV and TV translator stations. However, a television translator relay station license may be issued to a cooperative enterprise wholly owned by licensees of television broadcast translators or...

  13. An enzymatically-sensitized sequential and concentric energy transfer relay self-assembled around semiconductor quantum dots

    NASA Astrophysics Data System (ADS)

    Samanta, Anirban; Walper, Scott A.; Susumu, Kimihiro; Dwyer, Chris L.; Medintz, Igor L.

    2015-04-01

    The ability to control light energy within de novo nanoscale structures and devices will greatly benefit their continuing development and ultimate application. Ideally, this control should extend from generating the light itself to its spatial propagation within the device along with providing defined emission wavelength(s), all in a stand-alone modality. Here we design and characterize macromolecular nanoassemblies consisting of semiconductor quantum dots (QDs), several differentially dye-labeled peptides and the enzyme luciferase which cumulatively demonstrate many of these capabilities by engaging in multiple-sequential energy transfer steps. To create these structures, recombinantly-expressed luciferase and the dye-labeled peptides were appended with a terminal polyhistidine sequence allowing for controlled ratiometric self-assembly around the QDs via metal-affinity coordination. The QDs serve to provide multiple roles in these structures including as central assembly platforms or nanoscaffolds along with acting as a potent energy harvesting and transfer relay. The devices are activated by addition of coelenterazine H substrate which is oxidized by luciferase producing light energy which sensitizes the central 625 nm emitting QD acceptor by bioluminescence resonance energy transfer (BRET). The sensitized QD, in turn, acts as a relay and transfers the energy to a first peptide-labeled Alexa Fluor 647 acceptor dye displayed on its surface. This dye then transfers energy to a second red-shifted peptide-labeled dye acceptor on the QD surface through a second concentric Förster resonance energy transfer (FRET) process. Alexa Fluor 700 and Cy5.5 are both tested in the role of this terminal FRET acceptor. Photophysical analysis of spectral profiles from the resulting sequential BRET-FRET-FRET processes allow us to estimate the efficiency of each of the transfer steps. Importantly, the efficiency of each step within this energy transfer cascade can be controlled to some extent by the number of enzymes/peptides displayed on the QD. Further optimization of the energy transfer process(es) along with potential applications of such devices are finally discussed.The ability to control light energy within de novo nanoscale structures and devices will greatly benefit their continuing development and ultimate application. Ideally, this control should extend from generating the light itself to its spatial propagation within the device along with providing defined emission wavelength(s), all in a stand-alone modality. Here we design and characterize macromolecular nanoassemblies consisting of semiconductor quantum dots (QDs), several differentially dye-labeled peptides and the enzyme luciferase which cumulatively demonstrate many of these capabilities by engaging in multiple-sequential energy transfer steps. To create these structures, recombinantly-expressed luciferase and the dye-labeled peptides were appended with a terminal polyhistidine sequence allowing for controlled ratiometric self-assembly around the QDs via metal-affinity coordination. The QDs serve to provide multiple roles in these structures including as central assembly platforms or nanoscaffolds along with acting as a potent energy harvesting and transfer relay. The devices are activated by addition of coelenterazine H substrate which is oxidized by luciferase producing light energy which sensitizes the central 625 nm emitting QD acceptor by bioluminescence resonance energy transfer (BRET). The sensitized QD, in turn, acts as a relay and transfers the energy to a first peptide-labeled Alexa Fluor 647 acceptor dye displayed on its surface. This dye then transfers energy to a second red-shifted peptide-labeled dye acceptor on the QD surface through a second concentric Förster resonance energy transfer (FRET) process. Alexa Fluor 700 and Cy5.5 are both tested in the role of this terminal FRET acceptor. Photophysical analysis of spectral profiles from the resulting sequential BRET-FRET-FRET processes allow us to estimate the efficiency of each of the transfer steps. Importantly, the efficiency of each step within this energy transfer cascade can be controlled to some extent by the number of enzymes/peptides displayed on the QD. Further optimization of the energy transfer process(es) along with potential applications of such devices are finally discussed. Electronic supplementary information (ESI) available: This material includes control experimental data and select deconvoluted spectra. See DOI: 10.1039/c5nr00828j

  14. Corynebacterium diphtheriae methionine sulfoxide reductase a exploits a unique mycothiol redox relay mechanism.

    PubMed

    Tossounian, Maria-Armineh; Pedre, Brandán; Wahni, Khadija; Erdogan, Huriye; Vertommen, Didier; Van Molle, Inge; Messens, Joris

    2015-05-01

    Methionine sulfoxide reductases are conserved enzymes that reduce oxidized methionines in proteins and play a pivotal role in cellular redox signaling. We have unraveled the redox relay mechanisms of methionine sulfoxide reductase A of the pathogen Corynebacterium diphtheriae (Cd-MsrA) and shown that this enzyme is coupled to two independent redox relay pathways. Steady-state kinetics combined with mass spectrometry of Cd-MsrA mutants give a view of the essential cysteine residues for catalysis. Cd-MsrA combines a nucleophilic cysteine sulfenylation reaction with an intramolecular disulfide bond cascade linked to the thioredoxin pathway. Within this cascade, the oxidative equivalents are transferred to the surface of the protein while releasing the reduced substrate. Alternatively, MsrA catalyzes methionine sulfoxide reduction linked to the mycothiol/mycoredoxin-1 pathway. After the nucleophilic cysteine sulfenylation reaction, MsrA forms a mixed disulfide with mycothiol, which is transferred via a thiol disulfide relay mechanism to a second cysteine for reduction by mycoredoxin-1. With x-ray crystallography, we visualize two essential intermediates of the thioredoxin relay mechanism and a cacodylate molecule mimicking the substrate interactions in the active site. The interplay of both redox pathways in redox signaling regulation forms the basis for further research into the oxidative stress response of this pathogen. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Regulating the dorsal neural tube expression of Ptf1a through a distal 3' enhancer.

    PubMed

    Mona, Bishakha; Avila, John M; Meredith, David M; Kollipara, Rahul K; Johnson, Jane E

    2016-10-01

    Generating the correct balance of inhibitory and excitatory neurons in a neural network is essential for normal functioning of a nervous system. The neural network in the dorsal spinal cord functions in somatosensation where it modulates and relays sensory information from the periphery. PTF1A is a key transcriptional regulator present in a specific subset of neural progenitor cells in the dorsal spinal cord, cerebellum and retina that functions to specify an inhibitory neuronal fate while suppressing excitatory neuronal fates. Thus, the regulation of Ptf1a expression is critical for determining mechanisms controlling neuronal diversity in these regions of the nervous system. Here we identify a sequence conserved, tissue-specific enhancer located 10.8kb 3' of the Ptf1a coding region that is sufficient to direct expression to dorsal neural tube progenitors that give rise to neurons in the dorsal spinal cord in chick and mouse. DNA binding motifs for Paired homeodomain (Pd-HD) and zinc finger (ZF) transcription factors are required for enhancer activity. Mutations in these sequences implicate the Pd-HD motif for activator function and the ZF motif for repressor function. Although no repressor transcription factor was identified, both PAX6 and SOX3 can increase enhancer activity in reporter assays. Thus, Ptf1a is regulated by active and repressive inputs integrated through multiple sequence elements within a highly conserved sequence downstream of the Ptf1a gene. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. The Tracking & Data Relay Satellite System. The New Space Network.

    ERIC Educational Resources Information Center

    Froehlich, Walter

    This publication describes the giant-capacity space communications installation called the "Tracking and Data Relay Satellite System" (TDRSS). Chapters include: (1) "A New Communications Bridge to Orbit" (illustrating what it is and how it looks); (2) "TDRSS Goes to Work" (describing how it functions); (3) "The…

  17. 76 FR 58412 - Relay Services for Deaf-Blind Individuals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-21

    ... to distribute equipment and provide related services to eligible individuals throughout the state... communications services that will be used with the distributed equipment. (b) Each program certified under the... is used, and the type of relay service it can access; For each piece of equipment distributed, the...

  18. 77 FR 49710 - Airworthiness Directives; Sikorsky Aircraft Corporation Helicopters

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ... modifications, installation of a warning relay by following Sikorsky Customer Service Bulletin No. 76- 66-10B... helicopter. Related Service Information We have reviewed the following documents from Sikorsky: Customer... specifies installing an ERB warning relay kit; Customer Service Notice No. 76-113, dated June 1, 1983, which...

  19. Public Address Set AN/UIQ-10 (XLW-1)

    DTIC Science & Technology

    1972-01-01

    case. /,320 Hz No visible indication. Major Horizontal Broadband Resonance Resonance center located 300 to 500 peak at on case over relay bracket. ’ 375 ... Hz No visible indication. Minor Horizontal Broadband Resonance Resonance center located 150 to 190 peak at case over relay bracket. � Hz Slight

  20. Aerial Networking for the Implementation of Cooperative Control on Small Unmanned Aerial Systems

    DTIC Science & Technology

    2013-03-01

    the relay aircraft to an optimal location. Secondly, a mesh network was configured and tested. This configuration successfully relayed aircraft...functionality, such as updating navigation waypoints to each aircraft. The results suggest the system be updated with more capable modems in a mesh ...

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