WorldWideScience

Sample records for tvlf transmitter facility

  1. High-power magnetron transmitter as an RF source for the electron collider ring of the MEIC facility

    CERN Document Server

    Kazakevich, G

    2014-01-01

    A novel concept of high-power transmitters utilizing the Continuous Wave (CW) magnetrons, frequency-locked by phase-modulated signals has been proposed to compensate energy losses caused by Synchrotron Radiation (SR) in the electron ring of the MEIC facility. At operating frequency of about 750 MHz the SR losses are ~2 MW. They can be compensated by some number of Superconducting RF (SRF) cavities at the feeding power of about 100-200 kW per cavity. A high-power CW transmitters, based on magnetrons, frequency-locked by phase-modulated signal, allowing a wide-band control in phase and power, and associated with a wide-band closed feedback loop are proposed to feed the SRF cavities to compensate the SR losses of the electron beam in the MEIC collider electron ring.

  2. Transmittance Measurement of a Heliostat Facility used in the Preflight Radiometric Calibration of Earth-Observing Sensors

    Science.gov (United States)

    Czapla-Myers, J.; Thome, K.; Anderson, N.; McCorkel, J.; Leisso, N.; Good, W.; Collins, S.

    2009-01-01

    Ball Aerospace and Technologies Corporation in Boulder, Colorado, has developed a heliostat facility that will be used to determine the preflight radiometric calibration of Earth-observing sensors that operate in the solar-reflective regime. While automatically tracking the Sun, the heliostat directs the solar beam inside a thermal vacuum chamber, where the sensor under test resides. The main advantage to using the Sun as the illumination source for preflight radiometric calibration is because it will also be the source of illumination when the sensor is in flight. This minimizes errors in the pre- and post-launch calibration due to spectral mismatches. It also allows the instrument under test to operate at irradiance values similar to those on orbit. The Remote Sensing Group at the University of Arizona measured the transmittance of the heliostat facility using three methods, the first of which is a relative measurement made using a hyperspectral portable spectroradiometer and well-calibrated reference panel. The second method is also a relative measurement, and uses a 12-channel automated solar radiometer. The final method is an absolute measurement using a hyperspectral spectroradiometer and reference panel combination, where the spectroradiometer is calibrated on site using a solar-radiation-based calibration.

  3. Transmittance measurement of a heliostat facility used in the preflight radiometric calibration of Earth-observing sensors

    Science.gov (United States)

    Czapla-Myers, J.; Thome, K.; Anderson, N.; McCorkel, J.; Leisso, N.; Good, W.; Collins, S.

    2009-08-01

    Ball Aerospace and Technologies Corporation in Boulder, Colorado, has developed a heliostat facility that will be used to determine the preflight radiometric calibration of Earth-observing sensors that operate in the solar-reflective regime. While automatically tracking the Sun, the heliostat directs the solar beam inside a thermal vacuum chamber, where the sensor under test resides. The main advantage to using the Sun as the illumination source for preflight radiometric calibration is because it will also be the source of illumination when the sensor is in flight. This minimizes errors in the pre- and post-launch calibration due to spectral mismatches. It also allows the instrument under test to operate at irradiance values similar to those on orbit. The Remote Sensing Group at the University of Arizona measured the transmittance of the heliostat facility using three methods, the first of which is a relative measurement made using a hyperspectral portable spectroradiometer and well-calibrated reference panel. The second method is also a relative measurement, and uses a 12-channel automated solar radiometer. The final method is an absolute measurement using a hyperspectral spectroradiometer and reference panel combination, where the spectroradiometer is calibrated on site using a solar-radiation-based calibration.

  4. 47 CFR 22.507 - Number of transmitters per station.

    Science.gov (United States)

    2010-10-01

    ..., stand-alone transmitter is linked to the system via a control/repeater facility or by satellite... 47 Telecommunication 2 2010-10-01 2010-10-01 false Number of transmitters per station. 22.507 Section 22.507 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES...

  5. 47 CFR 74.461 - Transmitter power.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Transmitter power. 74.461 Section 74.461....461 Transmitter power. (a) Transmitter power is the power at the transmitter output terminals and.... For the purpose of this Subpart, the transmitter power is the carrier power. (b) The...

  6. Controlled crumpling of graphene oxide films for tunable optical transmittance.

    Science.gov (United States)

    Thomas, Abhay V; Andow, Brandon C; Suresh, Shravan; Eksik, Osman; Yin, Jie; Dyson, Anna H; Koratkar, Nikhil

    2015-06-01

    The delamination buckling approach provides a facile means to dynamically control the optical transmittance of extremely flexible and stretchable graphene oxide coatings with fast response time. Such graphene oxide coatings can be deposited by scalable solution-processing methods for potential applications in dynamic glazing.

  7. An optical analog signal transmitter

    Energy Technology Data Exchange (ETDEWEB)

    Fudzita, K.; Itida, T.; Tanaka, Kh.

    1984-01-11

    An optical laser analog signal transmitter employing an amplitude modulated subcarrier is patented; this transmitter performs stable and high quality transmission of information signals over great distances. A feature of the proposed transmitter is a special transmitter operational mode in which the light emission reflected off the connection point to the fiber optic conduit is sent back to the laser diode in a transient period. As a result, the critical mode of the generated emission is not influenced by the reflected signal. The transmitter consists of a laser diode with biasing near the cutoff point, an amplitude modulator with a subcarrier frequency oscillator, a section of flexible fiber-optic cable of length L, which connects the laser diode to the primary optical fiber conduit, and the connector itself. The subcarrier frequency may vary over wide ranges to establish the necessary correlation between the length of the light conduit section L and the return propagation time of the reflected light signal from the connection point to the laser diode. The difference between the lasing time of the light signal and the return time to the laser diode of the signal reflected off the connector is determined by the relation tau equals 2nL/c - mtauc, where L is the length of the connecting section; n is the refractivity of the optical fiber; c is the velocity of light; tauc is the period of the high frequency subcarrier signal; and m is an integer.

  8. Optimisation of radio transmitter locations in mobile telecommunications networks

    Directory of Open Access Journals (Sweden)

    Schmidt-Dumont, Thorsten

    2016-08-01

    Full Text Available Multiple factors have to be taken into account when mobile telecommunication network providers make decisions about radio transmitter placement. Generally, area coverage and the average signal level provided are of prime importance in these decisions. These criteria give rise to a bi-objective problem of facility location, with the goal of achieving an acceptable trade-off between maximising the total area coverage and maximising the average signal level provided to the demand region by a network of radio transmitters. This paper establishes a mathematical modelling framework, based on these two placement criteria, for evaluating the effectiveness of a given set of radio transmitter locations. In the framework, coverage is measured according to the degree of obstruction of the so-called ‘Fresnel zone’ that is formed between handset and base station, while signal strength is modelled taking radio wave propagation loss into account. This framework is used to formulate a novel bi-objective facility location model that may form the basis for decision support aimed at identifying high-quality transmitter location trade-off solutions for mobile telecommunication network providers. But it may also find application in various other contexts (such as radar, watchtower, or surveillance camera placement optimisation.

  9. [Pain and its main transmitters].

    Science.gov (United States)

    Costentin, J

    2000-03-01

    The pain message originates peripherally from a great variety of substances either released from preformed stores or extemporaneously synthetized. They stimulate or sensitize nociceptors which are associated with the peripheral endings of sensitive protoneurones. Their central endings release many types of transmitters in the dorsal horn of medulla (substance P, NO, CGRP.). At this level their release, triggered by the firing rate, is modulated by the stimulation of various presynaptic receptors operated by transmitters produced by either interneurones (enkephalins) or medullar descending neurons (dopamine, norepinephrine, serotonine). These modulations correspond to the so-called gate control. The sensitive consecutive neurones which climb towards various brain areas are submitted to contradictory influences. Several of them enhance the pain perception (nociceptin, cholecystokinin, neuropeptide FF.) whereas several other reduce it (endorphines, neurotensin, neuromedin N, anandamide.).

  10. 47 CFR 101.513 - Transmitter power.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Transmitter power. 101.513 Section 101.513... SERVICES 24 GHz Service and Digital Electronic Message Service § 101.513 Transmitter power. The transmitter power will be governed by § 101.113. Further, each application must contain an analysis...

  11. 47 CFR 80.215 - Transmitter power.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Transmitter power. 80.215 Section 80.215... MARITIME SERVICES General Technical Standards § 80.215 Transmitter power. (a) Transmitter power shown on the radio station authorization is the maximum power the licensee is authorized to use. Power...

  12. 47 CFR 101.807 - Transmitter power.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Transmitter power. 101.807 Section 101.807... SERVICES Local Television Transmission Service § 101.807 Transmitter power. Stations in this service will not be authorized to use transmitters having a rated power output in excess of the limits set forth...

  13. 47 CFR 90.549 - Transmitter certification.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Transmitter certification. 90.549 Section 90...-775 and 793-805 MHz Bands § 90.549 Transmitter certification. Transmitters operated in the 763-775 MHz... its certification procedure as required by § 90.203....

  14. Transmittal of the Calculation Package that Supports the Analysis of Performance of the Environmental Management Waste Management Facility Oak Ridge, Tennessee (Based 5-Cell Design Issued 8/14/09)

    Energy Technology Data Exchange (ETDEWEB)

    Williams M.J.

    2009-09-14

    This document presents the results of an assessment of the performance of a build-out of the Environmental Management Waste Management Facility (EMWMF). The EMWMF configuration that was assessed includes the as-constructed Cells 1 through 4, with a groundwater underdrain that was installed beneath Cell 3 during the winter of 2003-2004, and Cell 5, whose proposed design is an Addendum to Remedial Design Report for the Disposal of Oak Ridge Reservation Comprehensive Environmental Response, Compensation, and Liability Act of 1980 Waste, Oak Ridge, Tennessee, DOE/OR/01-1873&D2/A5/R1. The total capacity of the EMWMF with 5 cells is about 1.7 million cubic yards. This assessment was conducted to determine the conditions under which the approved Waste Acceptance Criteria (WAC) for the EMWMF found in the Attainment Plan for Risk/Toxicity-Based Waste Acceptance Criteria at the Oak Ridge Reservation, Oak Ridge, Tennessee [U.S. Department of Energy (DOE) 2001a], as revised for constituents added up to October 2008, would remain protective of public health and safety for a five-cell disposal facility. For consistency, the methods of analyses and the exposure scenario used to predict the performance of a five-cell disposal facility were identical to those used in the Remedial Investigation and Feasibility Study (RI/FS) and its addendum (DOE 1998a, DOE 1998b) to develop the approved WAC. To take advantage of new information and design changes departing from the conceptual design, the modeling domain and model calibration were upaded from those used in the RI/FS and its addendum. It should be noted that this analysis is not intended to justify or propose a change in the approved WAC.

  15. Intraperitoneal implantation of life-long telemetry transmitters in otariids.

    Science.gov (United States)

    Horning, Markus; Haulena, Martin; Tuomi, Pamela A; Mellish, Jo-Ann E

    2008-12-10

    Pinnipeds, including many endangered and declining species, are inaccessible and difficult to monitor for extended periods using externally attached telemetry devices that are shed during the annual molt. Archival satellite transmitters were implanted intraperitoneally into four rehabilitated California sea lions (Zalophus californianus) and 15 wild juvenile Steller sea lions (Eumetopias jubatus) to determine the viability of this surgical technique for the deployment of long-term telemetry devices in otariids. The life history transmitters record information throughout the life of the host and transmit data to orbiting satellites after extrusion following death of the host. Surgeries were performed under isoflurane anesthesia and single (n = 4) or dual (n = 15) transmitters were inserted into the ventrocaudal abdominal cavity via an 8.5 to 12 cm incision along the ventral midline between the umbilicus and pubic symphysis or preputial opening. Surgeries lasted 90 minutes (SD = 8) for the 19 sea lions. All animals recovered well and were released into the wild after extended monitoring periods from 27 to 69 days at two captive animal facilities. Minimum post-implant survival was determined via post-release tracking using externally attached satellite transmitters or via opportunistic re-sighting for mean durations of 73.7 days (SE = 9.0, Z. californianus) and 223.6 days (SE = 71.5, E. jubatus). The low morbidity and zero mortality encountered during captive observation and post-release tracking periods confirm the viability of this surgical technique for the implantation of long-term telemetry devices in otariids.

  16. Integrated Optical Transmitter and Receiver

    Science.gov (United States)

    1981-09-18

    Laser Development --Further laser development await the servicing of the GaAlAs/GaAs MOCVD reactor (see section D). During this period, work focused on continued high-speed measurements of narrow-diffused stripe laser structures grown by MOCVD, to be implemented into the integrated transmitter structure. Problems Encountered and/or Anticipated Work continued on isolating causes for growth control problems encountered last month on the GaAlAs/GaAs MOCVD system. These include inability to accurately tune the properties of the GaAlAs

  17. Ionospheric Modification from Under-Dense Heating by High-Power HF Transmitter

    Science.gov (United States)

    2011-03-03

    Auroral Research Program ( HAARP ) is a HF transmitter, which delivers 0.36 to 3.6 GW effective isotropic radiated powers (F.IRP) for the radiation...dense heating, the EIRP of the HAARP heater can be increased significantly by increasing the heater frequency. With higher heater frequency, the loss...1304 local time) and on 13 April from 0812 to 0844 UTC (0012 to 0044 local time), using the HAARP transmitter facility at Gakona, AK, at full power

  18. 47 CFR 22.657 - Transmitter locations.

    Science.gov (United States)

    2010-10-01

    ... effective radiated power (ERP) of the most powerful mobile transmitter(s) in the system: Mobile unit ERP... American Datum 1983 (NAD83). Urban area N. latitude W. longitude Houston, TX 29°45′26.8″ 95°21′37.8″ New... base transmitter locations in the New York-Northeastern New Jersey urban area that utilize an antenna...

  19. 77 FR 1779 - Emergency Locator Transmitters (ELTs)

    Science.gov (United States)

    2012-01-11

    ... Locator Transmitter (ELT) Equipment. SUMMARY: This notice announces the FAA's intent to cancel TSO-C91a, Emergency Locator Transmitter (ELT) Equipment. The effect of the cancelled TSO will result in no new TSO... existing TSO authorization (TSOA). Articles produced under an existing TSOA can still be...

  20. Hermetic diode laser transmitter module

    Science.gov (United States)

    Ollila, Jyrki; Kautio, Kari; Vahakangas, Jouko; Hannula, Tapio; Kopola, Harri K.; Oikarinen, Jorma; Sivonen, Matti

    1999-04-01

    In very demanding optoelectronic sensor applications it is necessary to encapsulate semiconductor components hermetically in metal housings to ensure reliable operation of the sensor. In this paper we report on the development work to package a laser diode transmitter module for a time- off-light distance sensor application. The module consists of a lens, laser diode, electronic circuit and optomechanics. Specifications include high acceleration, -40....+75 degree(s)C temperature range, very low gas leakage and mass-production capability. We have applied solder glasses for sealing optical lenses and electrical leads hermetically into a metal case. The lens-metal case sealing has been made by using a special soldering glass preform preserving the optical quality of the lens. The metal housings are finally sealed in an inert atmosphere by welding. The assembly concept to retain excellent optical power and tight optical axis alignment specifications is described. The reliability of the laser modules manufactured has been extensively tested using different aging and environmental test procedures. Sealed packages achieve MIL- 883 standard requirements for gas leakage.

  1. Intraperitoneal implantation of life-long telemetry transmitters in otariids

    Directory of Open Access Journals (Sweden)

    Haulena Martin

    2008-12-01

    Full Text Available Abstract Background Pinnipeds, including many endangered and declining species, are inaccessible and difficult to monitor for extended periods using externally attached telemetry devices that are shed during the annual molt. Archival satellite transmitters were implanted intraperitoneally into four rehabilitated California sea lions (Zalophus californianus and 15 wild juvenile Steller sea lions (Eumetopias jubatus to determine the viability of this surgical technique for the deployment of long-term telemetry devices in otariids. The life history transmitters record information throughout the life of the host and transmit data to orbiting satellites after extrusion following death of the host. Results Surgeries were performed under isoflurane anesthesia and single (n = 4 or dual (n = 15 transmitters were inserted into the ventrocaudal abdominal cavity via an 8.5 to 12 cm incision along the ventral midline between the umbilicus and pubic symphysis or preputial opening. Surgeries lasted 90 minutes (SD = 8 for the 19 sea lions. All animals recovered well and were released into the wild after extended monitoring periods from 27 to 69 days at two captive animal facilities. Minimum post-implant survival was determined via post-release tracking using externally attached satellite transmitters or via opportunistic re-sighting for mean durations of 73.7 days (SE = 9.0, Z. californianus and 223.6 days (SE = 71.5, E. jubatus. Conclusion The low morbidity and zero mortality encountered during captive observation and post-release tracking periods confirm the viability of this surgical technique for the implantation of long-term telemetry devices in otariids.

  2. Truth-value transmittal fuzzy reasoning interpolator

    Institute of Scientific and Technical Information of China (English)

    YAN Jianping; LEUNG Yee

    2005-01-01

    In this paper, we firstly associate fuzzy reasoning algorithm with the interpolation algorithm and discuss the limitation of defuzzification methods used commonly in the fuzzy reasoning algorithm. Secondly, we give a new fuzzy reasoning algorithm in case of single input, called the truth-value transmittal method, and discuss its properties. Finally, we analyze the rationality to adopy the truth-value transmittal method as the defuzzification method of full implication triple I method, and show that although CRI and triple I fuzzy reasoning method are different from fuzzy output set, they are uniform finally under the truth-value transmittal defuzzification method.

  3. Phase-coded pulse aperiodic transmitter coding

    Directory of Open Access Journals (Sweden)

    I. I. Virtanen

    2009-07-01

    Full Text Available Both ionospheric and weather radar communities have already adopted the method of transmitting radar pulses in an aperiodic manner when measuring moderately overspread targets. Among the users of the ionospheric radars, this method is called Aperiodic Transmitter Coding (ATC, whereas the weather radar users have adopted the term Simultaneous Multiple Pulse-Repetition Frequency (SMPRF. When probing the ionosphere at the carrier frequencies of the EISCAT Incoherent Scatter Radar facilities, the range extent of the detectable target is typically of the order of one thousand kilometers – about seven milliseconds – whereas the characteristic correlation time of the scattered signal varies from a few milliseconds in the D-region to only tens of microseconds in the F-region. If one is interested in estimating the scattering autocorrelation function (ACF at time lags shorter than the F-region correlation time, the D-region must be considered as a moderately overspread target, whereas the F-region is a severely overspread one. Given the technical restrictions of the radar hardware, a combination of ATC and phase-coded long pulses is advantageous for this kind of target. We evaluate such an experiment under infinitely low signal-to-noise ratio (SNR conditions using lag profile inversion. In addition, a qualitative evaluation under high-SNR conditions is performed by analysing simulated data. The results show that an acceptable estimation accuracy and a very good lag resolution in the D-region can be achieved with a pulse length long enough for simultaneous E- and F-region measurements with a reasonable lag extent. The new experiment design is tested with the EISCAT Tromsø VHF (224 MHz radar. An example of a full D/E/F-region ACF from the test run is shown at the end of the paper.

  4. INDIVIDUAL COMMUNICATION TRANSMITTER IDENTIFICATION BASED ON MULTIFRACTAL ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    Ren Chunhui; Wei Ping; Lou Zhiyou; Xiao Xianci

    2005-01-01

    In this letter, the communication transmitter transient signals are analyzed based on the time-variant hierarchy exponents of multifractal analysis. The species of optimized sample set is selected as the template of transmitter identification, so that the individual communication transmitter identification can be realized. The turn-on signals of four transmitters are used in the simulation. The experimental results show that the multifractal character of transmitter transient signals is an effective character of individual transmitter identification.

  5. Quantum Communications Transmitter at 775 nm Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel new architecture for a quantum communications laser transmitter that is designed for free-space polarization encoded quantum key distribution...

  6. Digital transmitter for data bus communications system

    Science.gov (United States)

    Proch, G. E. (Inventor)

    1975-01-01

    An improved digital transmitter for transmitting serial pulse code modulation (pcm) data at high bit rates over a transmission line is disclosed. When not transmitting, the transmitter features a high output impedance which prevents the transmitter from loading the transmission line. The pcm input is supplied to a logic control circuit which produces two discrete logic level signals which are supplied to an amplifier. The amplifier, which is transformer coupled to the output isolation circuitry, converts the discrete logic level signals to two high current level, ground isolated signals in the secondary windings of the coupling transformer. The latter signals are employed as inputs to the isolation circuitry which includes two series transistor pairs operating into a hybrid transformer functioning to isolate the transmitter circuitry from the transmission line.

  7. 47 CFR 15.212 - Modular transmitters.

    Science.gov (United States)

    2010-10-01

    ... modular transmitter must have their own shielding. The physical crystal and tuning capacitors may be... shielded. The physical crystal and tuning capacitors may be located external to the shielded radio...

  8. World War II Weather Record Transmittances

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — World War II Weather Record Transmittances are a record of the weather and meteorological data observed during World War II and transferred to the archive. It...

  9. Transionospheric Propagation of VLF Transmitter Signals

    Science.gov (United States)

    Cohen, M.; Inan, U. S.; Lehtinen, N. G.

    2012-12-01

    Ground based Very Low Frequency (VLF, 3-30 kHz) radio transmitters may play a significant role in precipitation of inner belt (L<2.5) energetic Van Allen electrons. Initial analyses of the total contribution of VLF transmitters utilized models of transionospheric propagation, but some recent studies have suggested that those models may overestimate (by 20-100 dB) the VLF energy reaching the magnetosphere. One possible cause of this discrepancy was suggested to be conversion of wave energy into electrostatic modes in the D, E, and F regions, from ionospheric density irregularities, either natural or generated by the transmitter heating itself. The DEMETER satellite built a six year history of continuous and global survey mode data which, when combined, yields detailed pictures of the radiation pattern from many transmitters into space at 680 km, with 25 km resolution, and clear features like the interference pattern on the ground mapped upwards. With both E and B survey mode data, we can also directly approximate the total power injected into the magnetosphere from each transmitter, separately for day and night, as well as the power arriving at the conjugate region. We find no detectable variation of signal intensity with geomagnetic conditions. We find evidence of transmitter heating affecting the transionospheric propagation of other transmitters. We find that the power reaching the conjugate region is a large fraction of the power injected above the transmitter. We then employ a full wave model to simulate VLF transmitter transionospheric propagation, calculating the electromagnetic fields and power flux injected into the magnetosphere. Although the model does not include ionospheric irregularities, the radiation pattern largely matches the observed one, and the total power calculated is within 6 dB of observations for every transmitter, both day and night, and across a range of low to middle latitudes and transmitter powers. We thus conclude that the effect of

  10. Terrestrial VLF transmitter injection into the magnetosphere

    OpenAIRE

    2012-01-01

    Terrestrial VLF transmitter injection into the magnetosphere M. B. Cohen1 and U. S. Inan1,2 Received 1 June 2012; revised 15 June 2012; accepted 18 June 2012; published 9 August 2012. [1] Very Low Frequency (VLF, 3–30 kHz) radio waves emitted from ground sources (transmitters and lightning) strongly impact the radiation belts, driving electron precipitation via whistler-electron gyroresonance, and contributing to the formation of the slot region. However, calculations of the...

  11. Direct RF modulation transmitter, sampling clock frequency setting method for direct RF modulation transmitter

    NARCIS (Netherlands)

    Fukuda, Shuichi; Nauta, Bram

    2013-01-01

    PROBLEM TO BE SOLVED: To provide a direct RF modulation transmitter capable of satisfying a radiation level regulation even without providing a SAW filter. SOLUTION: A direct RF modulation transmitter includes: digital/RF converters 105, 106 to which an I digital baseband signal, a Q digital baseb

  12. Retention and effects of miniature transmitters in juvenile American eels

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Robert P.; Janak, Jill; Liss, Stephanie A.; Brown, Richard S.; Deng, Zhiqun; Harnish, Ryan A.

    2017-11-01

    This study was conducted to assess the effects of a non-functional acoustic micro transmitter (tag) on survival, tag loss, and swimming ability of juvenile American eels (Anguilla rostrata). The transmitter was designed for implantation through a < 3 mm opening into the body cavity of anguilliform fishes without the need for sutures. American eels used for the swimming performance study were 113–175 mm (N = 120). There were two treatment groups (tagged and non-tagged), each treatment was split into six size groups of 10 mm for testing. Potential transmitter effects on swimming performance were examined by comparing critical swimming speeds (Ucrit an index of prolonged swimming performance) for tagged and non-tagged eels. There was no significant difference in Ucrit between tagged and non-tagged eels for all of the size groups tested. Median Ucrits for tagged eels ranged from 50.2 cm/s for the smallest group tested (113–119 mm) to 63.9 cm/s for fish 141–150 mm in length. Non-tagged group median Ucrits ranged from 47.2 cm/s for the smallest group to 66.9 cm/s for the 141–150 mm group. An additional 26 eels (115–208 mm) were tagged and held for 38 d (without undergoing swimming performance tests) to determine the effects on survival and tag loss. There was no mortality during the holding period and the majority of the tag loss occurred after 20 days post-tagging, which is the current projected life of the tag. Our results indicate that micro acoustic tags can be successfully implanted in juvenile American eels with no apparent impacts to swimming ability, and would be a viable option for examining eel movement patterns in river systems and near hydroelectric facilities.

  13. Design and Implementation of HDMI Transmitter

    Directory of Open Access Journals (Sweden)

    C.Srinivasan

    2016-11-01

    Full Text Available The High-Definition Multimedia Interface is provided for transmitting digital television audio-visual signals from DVD players, set-top boxes and other audio-visual sources to television sets, projectors and other video displays. HDMI is used in various real time applications for transmitting and receiving audio-visual Signals. A transaction level model of HDMI Transmitter is designed by using System Verilog. Transaction Level Modeling methodologies promote the growth of System Level Description Language. This paper presents a HDMI Transmitter Transaction Level Modeling Design which can be used to easily transform to HDL descriptions for subsequent RTL (Register Transfer Level Design

  14. Simulation Approach for Safety Evaluation of Smart Transmitters in NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Yeong Jin; Jeong, Sang Yong; Kim, Hyung Tae; Choo, Jaeyul; Park, Hyun Shin; Jeong, Choong Heui [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of); Lee, Jea Heung [Hanbat National University, Daejeon (Korea, Republic of)

    2015-10-15

    Smart transmitters which are microprocessor-based device including software have been used for various industry. The necessity of preparing the regulatory guide or safety review plan for the smart transmitter is increased before using the smart transmitter for safety function. So the two year simulated approach study plan to extract some generic characteristics not limited typical smart transmitter was setup in Dec. 2014 to safety evaluation of safety grade smart transmitter. This paper addresses the considerations on safety evaluation and simulated approach for smart transmitter of the first year and middle of the second year study. This paper showed the first year and the middle of the second year activity for the smart transmitter safety evaluation and simulated approach. The PC-smart transmitter test bed was setup and the test case for confirming the characteristics of the smart transmitter has been established.

  15. Agricultural applications of NIR reflectance and transmittance

    DEFF Research Database (Denmark)

    Gislum, René

    2009-01-01

    There has been a considerable increase in the use of near infrared (NIR) reflectance and transmittance spectroscopy technologies for rapid determination of quality parameters in agriculture, including applications within crop product quality, feed and food quality, manure quality, soil analyses etc...

  16. Transmitter systems in the primate dentate gyrus.

    Science.gov (United States)

    Amaral, D G; Campbell, M J

    1986-01-01

    While the dentate gyrus is clearly the simplest of the cortical fields that constitute the hippocampal formation, it nonetheless occupies a pivotal position in the flow of information through this region. Though it has been the subject of anatomical study for over a century and its major connections have been known for almost as long, the use of newly developed histochemical and immunohistochemical techniques have demonstrated many new facets of its intrinsic connectivity and afferent innervation. These techniques have established that it is innervated by cholinergic, noradrenergic, serotonergic and dopaminergic fibers. More recent studies have shown that fibers and cell bodies of the dentate gyrus are immunoreactive for variety of neuroactive substances including the excitatory amino acids glutamate and aspartate, the inhibitory transmitter GABA, as well as peptides of many types including the opioid peptides, enkephalin and dynorphin, several forms of somatostatin, neuropeptide Y, cholycystokinin, vasoactive intestinal peptide and substance P. In this review, we will briefly summarize the distribution of each of these putative transmitter systems within the dentate gyrus. The perspective emerges that the plethora of newly identified and chemically specific fiber systems enriches the classical understanding of the organization of this relatively simple cortical structure. Since there is thus far no evidence for the exclusion from the dentate gyrus of any class of transmitter bearing fiber or neuron found in the neocortex, it can be viewed as a relatively simple model system for studying the interactions of specific transmitter systems in a laminated, cortical structure.

  17. Mortality, Transmitter Retention, Growth, and Wound Healing in Juvenile Salmon Injected with Micro Acoustic Transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Liss, Stephanie A.; Brown, Richard S.; Deters, Katherine A.; Walker, Ricardo W.; Deng, Z. Daniel; Eppard, M. Brad; Townsend, Richard L.; Seaburg, Adam G.

    2016-07-28

    A cylindrical acoustic transmitter (AT; 0.2 g) has been developed for injection into the peritoneum of fish. Laboratory studies can provide tagging guidelines to minimize the effect of implantation techniques and transmitter burden (relative weight of the transmitter to the weight of the fish) in fish before a transmitter is used in field studies. The goal of this study was to examine response variables (mortality, transmitter expulsion, growth, wound area) of juvenile Chinook Salmon (Oncorhynchus tschawytscha; 65–104 mm fork length [FL]) injected with an AT along a wide range of sizes that could lead to a guideline for minimizing tagging effects. The overarching goal was to determine a minimum size threshold for fish that can be injected, while minimizing adverse transmitter effects. Juveniles (n = 700) were separated into four treatments: (1) acoustic transmitter injection (AT), (2) AT and a passive integrated transponder tag injection (AT+PIT), (3) visual implant elastomer injection (Marked control), and (4) unmarked (Unmarked control). Fish were evaluated weekly for four weeks, and again at the end of the study (60 d post-tagging). Fish injected with an AT or an AT+PIT experienced greater mortality than Marked controls. By 60 d post-tagging, transmitter expulsion was 44% for AT fish and 20% for AT+PIT fish. Fish injected with an AT or an AT+PIT grew (FL and weight gain) significantly less than Marked controls, and no minimum size thresholds were detected. Finally, initial size (FL) significantly affected wound area in AT and AT+PIT fish. A size threshold was only identified on Day 7 (85.1 mm) for AT+PIT fish, indicating that wound areas in fish < 85.1 mm were larger than wound areas of fish > 85.1 mm. This research suggests that injecting juveniles with an AT or an AT+PIT had a greater effect on smaller fish than larger fish.

  18. Implementation of Universal Asynchronous Receiver and Transmitter

    Directory of Open Access Journals (Sweden)

    Payata Srikanth Yadav

    2015-03-01

    Full Text Available Universal Asynchronous Receiver Transmitter (UART is the serial communication protocol that is used for data exchange between computer & peripherals. UART is a low velocity, short-distance, low-cost protocol. UART includes three modules which are received, the baud rate generator and transmitter. The UART design with Very High Description Language can be integrated into the Field Programmable Gate Array to achieve stable data transmission and to make system reliable and compact. In the result and simulation part, this project will focus on check the receive data with error free & baud rate generation at different frequencies. Before synthesizing of UART a baud rate generator is incorporated into the system. We use the frequency divider which sets itself to required frequency for the functionality at lower frequency. All modules are designed using VERILOG and implemented on Xilinx Suite development board.

  19. Analog Dithering Techniques for Wireless Transmitters

    CERN Document Server

    Arfaei Malekzadeh, Foad; Roermund, Arthur H M

    2013-01-01

    This book describes innovative techniques and the theoretical background for design and analysis of high performance RF/Microwave transmitters. It introduces new, robust   linearization/efficiency enhancement techniques, applicable to all of the switched mode power amplifiers. Novel analysis methods associated with these new techniques are also introduced and supporting measurement results are documented.  Innovative graphical representation methods are used to help the reader understand the matter intuitively.  Applications for the techniques discussed are very extensive, ranging from data convertors to RF/Microwave/mm-wave wireless/wire line transmitters. The authors have avoided using lengthy formulas in the discussion and have used an intuitive and simple approach to go through the necessary details.  Readers will gain valuable understanding of the dither phenomenon, its mechanism, effect and undesired side effects. The novel architectures introduced are simple, don’t require complicated DSP techni...

  20. A solid state transmitter with adaptive beamforming

    Science.gov (United States)

    Wallington, J. R.; Chrystie, P. J.

    In many transmitter applications it is desirable to provide low sidelobe streerable radiation patterns from an array fed by multiple identical solid state sources. A feed network for an experimental linear array which allows this to be accomplished by means of 'phase shift only' control of array element amplitude and phase is described. Details of the experimental equipment and measured radiation patterns, in both the transmit and receive mode, are presented.

  1. 5 Watt, Solid State, EHF Transmitter.

    Science.gov (United States)

    2014-09-26

    satellite-communication ground terminals. This state-of- the- art transmitter demonstrates efficient and cost-effective RF power generation at EHF for...are relatively little or no spectrum allocation problems, is that the state-of-the- art in RF power generation is far below the required levels for...accomplished using E-H hybrid magic tees of reduced height waveguide with good balance and isolation characteristics. Modulation and other signal

  2. Classical transmitters and their receptors in flatworms.

    Science.gov (United States)

    Ribeiro, P; El-Shehabi, F; Patocka, N

    2005-01-01

    The flatworm nervous system employs a wide repertoire of neuroactive substances, including small chemical messengers, the so called classical transmitters, and several types of neuropeptides. A large body of research accumulated over four decades has provided a wealth of information on the tissue localization and effects of these substances, their biochemistry and, recently, their molecular modes of action in all major classes of flatworms. This evidence will be reviewed, with particular emphasis on the small (classical) transmitters and the receptors that mediate their effects. One of the themes that will emerge from this discussion is that classical transmitters regulate core activities such as movement, metabolism and transport, and thus are essential for survival of the organism. In addition, the evidence shows that flatworms have multiple neurotransmitter receptors, many with unusual pharmacological features, which make them particularly attractive as drug targets. Understanding the molecular basis of these distinctive properties, and developing new, more specific receptor agonists and antagonists will undoubtedly become a major challenge in future research.

  3. Temperature and temporal dependence of neutral density transmittance standards

    Science.gov (United States)

    Koo, A.; Hamlin, J. D.

    2012-04-01

    The Schott series of NG glasses are frequently used to manufacture neutral density transmittance standards for validation of spectrophotometer systems as well as for comparisons of regular spectral transmittance scales. A study has been made of the temperature and temporal dependence of transmittance in these types of filters. The temperature dependence of transmittance is found to scale as -ln(T). The filter transmittance was found to vary significantly with time shortly after manufacture but appears to be stabilizing nine months after beginning measurements.

  4. Measurement method for light transmittance of layered metamaterials.

    Science.gov (United States)

    Isozaki, Akihiro; Kan, Tetsuo; Ajiki, Yoshiharu; Matsumoto, Kiyoshi; Shimoyama, Isao

    2013-06-01

    We propose a method to measure light transmittance of layered metamaterials by placing the metamaterials directly on a Si photodiode. Our measurement method enables the direct detection of transmitted light that appears as an evanescent wave in natural materials. Here, we report the transmittance measurements of a typical metamaterial using this method. The metamaterial was composed of Ag/Al(2)O(3) layers and was fabricated by direct evaporation on the Si photodiode. The measured transmittance agrees with the simulated transmittance. Our results confirmed that this measurement method can determine the transmittance properties of metamaterials and that it is applicable to other types of metamaterials.

  5. 47 CFR 90.471 - Points of operation in internal transmitter control systems.

    Science.gov (United States)

    2010-10-01

    ...) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Transmitter Control Internal Transmitter Control Systems § 90.471 Points of operation in internal transmitter control systems. The... licensee for internal communications and transmitter control purposes. Operating positions in...

  6. Transmitter microdischarges in communications and broadcast Satellites

    Science.gov (United States)

    Briskman, Robert D.; Kaliski, Michael A. R.

    2016-09-01

    Most commercial communications and broadcast satellites operating at microwave radio frequencies use traveling wave tube amplifiers (TWTAs) as high power transmitters. Since TWTAs work at high voltages, it is not uncommon to experience micro-discharges, especially early in life. This observation led to the introduction of an autonomous restart function in the companion high voltage power supply (the electronic power conditioner or EPC) of the TWTA as a safety feature. A microdischarge with enough energy above a threshold would lead to a momentary removal of high voltages, followed by an automatic restart, which is usually sufficient to allow the microdischarge event to clear with minimal loss of RF transmission. In most cases the energy involved in the microdischarge is low enough that the removal of high voltages is not required and the event may go undetected. However, an unusual signature was first noted in early 1997 on a Ku-band satellite transmitter, where the characteristics of the microdischarge event were such that the control anode voltage dropped below nominal and typically recovered over a 20 min period. Such microdischarge events became known as the "20 min Effect" which has since been observed over subsequent years on other Ku-band TWTAs, as well as on Ka-band and S-band satellite TWTA transmitters in numerous satellites. This paper summarizes the in-orbit data on such microdischarges as well as the believed cause. In addition, the paper includes results from three S-band TWTAs which have operated on life test for many years. Due to ease of their monitoring instrumentation as contrast to monitoring microdischarges on orbiting operational satellites via telemetry, new data have been accumulated on this effect. The data substantiate the previous findings that microdischarges do not significantly affect satellite operation or their transmissions nor diminish the TWTAs performance, including long lifetime.

  7. An efficient magnetron transmitter for superconducting accelerators

    Science.gov (United States)

    Kazakevich, G.; Lebedev, V.; Yakovlev, V.; Pavlov, V.

    2016-12-01

    A concept of a highly-efficient high-power magnetron transmitter allowing wide-band phase and the mid-frequency power control at the frequency of the locking signal is proposed. The proposal is aimed for powering Superconducting RF (SRF) cavities of intensity-frontier accelerators. The transmitter is intended to operate with phase and amplitude control feedback loops allowing suppression of microphonics and beam loading in the SRF cavities. The concept utilizes injection-locked magnetrons controlled in phase by the locking signal supplied by a feedback system. The injection-locking signal pre-excites the magnetron and allows its operation below the critical voltage in free run. This realizes control of the magnetron power in an extended range (up to 10 dB) by control of the magnetron current. Experimental studies were carried out with 2.45 GHz, 1 kW, CW magnetrons. They demonstrated stable operation of the magnetrons and the required range of power control at a low noise level. An analysis of the kinetics of the drifting charge within the framework of the presented model of phase focusing in magnetrons substantiates the concept and the experimental results.

  8. Dynamic reliability of digital-based transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Brissaud, Florent, E-mail: florent.brissaud.2007@utt.f [Institut National de l' Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France) and Universite de Technologie de Troyes - UTT, Institut Charles Delaunay - ICD and UMR CNRS 6279 STMR, 12 rue Marie Curie, BP 2060, 10010 Troyes Cedex (France); Smidts, Carol [Ohio State University (OSU), Nuclear Engineering Program, Department of Mechanical Engineering, Scott Laboratory, 201 W 19th Ave, Columbus OH 43210 (United States); Barros, Anne; Berenguer, Christophe [Universite de Technologie de Troyes (UTT), Institut Charles Delaunay (ICD) and UMR CNRS 6279 STMR, 12 rue Marie Curie, BP 2060, 10010 Troyes Cedex (France)

    2011-07-15

    Dynamic reliability explicitly handles the interactions between the stochastic behaviour of system components and the deterministic behaviour of process variables. While dynamic reliability provides a more efficient and realistic way to perform probabilistic risk assessment than 'static' approaches, its industrial level applications are still limited. Factors contributing to this situation are the inherent complexity of the theory and the lack of a generic platform. More recently the increased use of digital-based systems has also introduced additional modelling challenges related to specific interactions between system components. Typical examples are the 'intelligent transmitters' which are able to exchange information, and to perform internal data processing and advanced functionalities. To make a contribution to solving these challenges, the mathematical framework of dynamic reliability is extended to handle the data and information which are processed and exchanged between systems components. Stochastic deviations that may affect system properties are also introduced to enhance the modelling of failures. A formalized Petri net approach is then presented to perform the corresponding reliability analyses using numerical methods. Following this formalism, a versatile model for the dynamic reliability modelling of digital-based transmitters is proposed. Finally the framework's flexibility and effectiveness is demonstrated on a substantial case study involving a simplified model of a nuclear fast reactor.

  9. Behavior of sandhill cranes harnessed with different satellite transmitters

    Science.gov (United States)

    Olsen, G.H.; Ellis, D.H.; Landfried, S.E.; Miller, L.H.; Klugman, S.S.; Fuller, M.R.; Vermillion, C.H.

    1992-01-01

    The effectiveness of various attachment methods and designs of platform transmitting terminals (PTT's) was tested on captive sandhill cranes (Grus canadensis) at the Patuxent Wildlife Research Center, Laurel, Maryland, during 1989-91. Combinations of attachment and transmitter designs included neoprene cord harness with batteries separate from the transmitter (2 harness designs), Teflon ribbon harness with batteries incorporated into the transmitter package (4 transmitter models), and a package attached directly to the bird with epoxy glue only. Physical effects seen on cranes wearing PTT's ranged from skin lacerations (caused by rubbing of harness material) to no observed effects (other than feather wear). The most successful harness material and design utilized a Teflon ribbon harness with the 4 ribbon ends from the transmitter forming a neck loop and a body loop joined at the sternum. Time spent by sandhill cranes performing most activities did not change after transmitter attachment using this harness method.

  10. Abnormal Modulation of Dielectric Band Transmittance of Polystyrene Opal

    Institute of Scientific and Technical Information of China (English)

    HU Xiao-Yong; GONG Qi-Huang; CHENG Bing-Ying; ZHANG Dao-Zhong

    2005-01-01

    @@ The abnormal transmittance in the dielectric band edge of a polystyrene opal is observed and analysed. The transmittance is periodically modulated and the period of modulation varies with the wavelength, which destroys the perfect structure of the photonic band gap. The transmittance modulation originates from the propagation of the low order whispering-gallery mode excited in polystyrene spheres. These results indicate that the whisperinggallery mode has a great influence on practical applications of polystyrene opal.

  11. 47 CFR 97.313 - Transmitter power standards.

    Science.gov (United States)

    2010-10-01

    ... transmitter power exceeding 5 W PEP on the UHF 23 cm band when the control operator is a Novice operator. (f... station may transmit with a transmitter power exceeding 1.5 kW PEP. (c) No station may transmit with a transmitter power output exceeding 200 W PEP: (1) On the 10.10-10.15 MHz segment; (2) On the 3.525-3.60 MHz, 7...

  12. Thermal Design and Flight Validation for Solid-state Transmitter

    Directory of Open Access Journals (Sweden)

    Wang Lei

    2014-06-01

    Full Text Available Solid-state transmitter with large power and high heat flux is a key equipment of an HJ-1-C satellite; therefore, it has a great influence on satellite thermal design. Thermal design ensures that the solid-state transmitter works well within the allowable temperature limits of the equipment. The solid-state transmitter thermal design and solved key problems are provided in accordance with the HJ-1-C characteristics. Moreover, an analysis of satellites on orbit was performed. Based on the telemetry data, the thermal control design is shown to satisfy the temperature requirements of the solid-state transmitter.

  13. Optical Transmitter Terminal for Selective RF High Frequency Bans Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of the proposal work is to investigate the highly innovative conceptual design of an optical communication selective frequency transmitter terminal...

  14. Opportunistic transmitter selection for selfless overlay cognitive radios

    KAUST Repository

    Shaqfeh, Mohammad

    2013-11-01

    We propose an opportunistic strategy to grant channel access to the primary and secondary transmitters in causal selfless overlay cognitive radios over block-fading channels. The secondary transmitter helps the primary transmitter by relaying the primary messages opportunistically, aided by a buffer to store the primary messages temporarily. The optimal channel-aware transmitter- selection strategy is the solution of the maximization of the average secondary rate under the average primary rate requirement and the buffer stability constraints. Numerical results demonstrate the gains of the proposed opportunistic selection strategy. © 2013 IEEE.

  15. Optical Transmittance of Anodically Oxidized Aluminum Alloy

    Science.gov (United States)

    Saito, Mitsunori; Shiga, Yasunori; Miyagi, Mitsunobu; Wada, Kenji; Ono, Sachiko

    1995-06-01

    Optical transmittance and anisotropy of anodic oxide films that were made from pure aluminum and an aluminum alloy (A5052) were studied. The alloy oxide film exhibits an enhanced polarization function, particularly when anodization is carried out at a large current density. It was revealed by chemical analysis that the alloy oxide film contains a larger amount of unoxidized aluminum than the pure-aluminum oxide film. The polarization function can be elucidated by considering unoxidized aluminum particles that are arranged in the columnar structure of the alumina film. Electron microscope observation showed that many holes exist in the alloy oxide film, around which columnar cells are arranged irregularly. Such holes and irregular cell arrangement cause the increase in the amount of unoxidized aluminum, and consequently induces scattering loss.

  16. Atmospheric transmittance model for photosynthetically active radiation

    Energy Technology Data Exchange (ETDEWEB)

    Paulescu, Marius; Stefu, Nicoleta; Gravila, Paul; Paulescu, Eugenia; Boata, Remus; Pacurar, Angel; Mares, Oana [Physics Department, West University of Timisoara, V Parvan 4, 300223 Timisoara (Romania); Pop, Nicolina [Department of Physical Foundations of Engineering, Politehnica University of Timisoara, V Parvan 2, 300223 Timisoara (Romania); Calinoiu, Delia [Mechanical Engineering Faculty, Politehnica University of Timisoara, Mihai Viteazu 1, 300222 Timisoara (Romania)

    2013-11-13

    A parametric model of the atmospheric transmittance in the PAR band is presented. The model can be straightforwardly applied for calculating the beam, diffuse and global components of the PAR solar irradiance. The required inputs are: air pressure, ozone, water vapor and nitrogen dioxide column content, Ångström's turbidity coefficient and single scattering albedo. Comparison with other models and ground measured data shows a reasonable level of accuracy for this model, making it suitable for practical applications. From the computational point of view the calculus is condensed into simple algebra which is a noticeable advantage. For users interested in speed-intensive computation of the effective PAR solar irradiance, a PC program based on the parametric equations along with a user guide are available online at http://solar.physics.uvt.ro/srms.

  17. How does a little acronym become a big transmitter?

    Science.gov (United States)

    Krnjević, Kresimir

    2004-10-15

    After an overview of the early, chequered history of the discovery of GABA and its gradual acceptance as inhibitory synaptic transmitter in the brain, the article lists and discusses some of the more unexpected later developments in studies of GABA, especially its role as excitatory transmitter in the immature brain.

  18. 47 CFR 95.667 - CB transmitter power.

    Science.gov (United States)

    2010-10-01

    ... transmitter power. The dissipation rating of all the semiconductors or electron tubes which supply RF power to the antenna terminals of each CB transmitter must not exceed 10 W. For semiconductors, the dissipation... semiconductor. These values may be temperature de-rated by no more than 50 °C. For an electron tube,...

  19. An Energy Harvesting Underwater Acoustic Transmitter for Aquatic Animals

    Energy Technology Data Exchange (ETDEWEB)

    Li, Huidong; Tian, Chuan; Lu, Jun; Myjak, Mitchell J.; Martinez, Jayson J.; Brown, Richard S.; Deng, Zhiqun Daniel

    2016-09-20

    This paper presents a self-powered underwater acoustic transmitter using a piezoelectric beam to harvest the mechanical energy from fish swimming. This transmitter does not require a battery and is demonstrated in live fish. It transmits an acoustic waveform as the implanted fish swims. It enables long-term monitoring of aquatic animals.

  20. 47 CFR 80.209 - Transmitter frequency tolerances.

    Science.gov (United States)

    2010-10-01

    ... facsimile emissions 20 Hz. For narrow-band direct printing and data emissions 10 Hz. 2 For digital selective... emissions 20 Hz. For transmitters with narrow-band direct printing and data emissions 10 Hz 2 For transmitters with digital selective calling emissions 10 Hz. For all other emissions 100. (ii) Ship...

  1. 43 CFR 4.702 - Transmittal of appeal file.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Transmittal of appeal file. 4.702 Section... PROCEDURES Special Rules Applicable to Other Appeals and Hearings § 4.702 Transmittal of appeal file. Within... decision is being appealed shall transmit to the Office of the Director the entire official file in...

  2. All-optical orthogonal frequency division multiplexing (OFDM) transmitter

    DEFF Research Database (Denmark)

    2015-01-01

    The invention relates to an all-optical orthogonal frequency division multiplexing (OFDM) transmitter for generating an OFDM output signal. The transmitter comprises a first time-domain optical Fourier transform (OFT) assembly, the first OFT assembly is of a K-D-K configuration and comprises...

  3. 47 CFR 73.685 - Transmitter location and antenna system.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Transmitter location and antenna system. 73.685... RADIO BROADCAST SERVICES Television Broadcast Stations § 73.685 Transmitter location and antenna system... and antenna height above average terrain employed, the following minimum field strength in dB...

  4. Juvenile Salmon Acoustic Telemetry System Transmitter Downsize Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Thomas J.; Myjak, Mitchell J.

    2010-04-30

    At the request of the U.S. Army Corps of Engineers, Portland District, researchers from Pacific Northwest National Laboratory investigated the use of an application-specific integrated circuit (ASIC) to reduce the weight and volume of Juvenile Salmon Acoustic Telemetry System (JSATS) transmitters while retaining current functionality. Review of the design of current JSATS transmitters identified components that could be replaced by an ASIC while retaining the function of the current transmitter and offering opportunities to extend function if desired. ASIC design alternatives were identified that could meet transmitter weight and volume targets of 200 mg and 100 mm3. If alternatives to the cylindrical batteries used in current JSATS transmitters can be identified, it could be possible to implant ASIC-based JSATS transmitters by injection rather than surgery. Using criteria for the size of fish suitable for surgical implantation of current JSATS transmitters, it was concluded that fish as small as 70 mm in length could be implanted with an ASIC-based transmitter, particularly if implantation by injection became feasible.

  5. A CONTACTLESS TRANSMITTER FOR THE M TYPE DATA TRANSMISSION SYSTEM.

    Science.gov (United States)

    A contactless transmitter employing electromagnetic principles for the M type data transmission system is described. It could be contained in a size 11 standard housing if the six semiconductor main switches are mounted externally. Tests showed that the transmitter will operate satisfactorily at speeds in excess of 3000 rev/min, and that it could form the basis of a brushless dc motor . (Author)

  6. A High Efficiency Fully Integrated OOK Transmitter for WBAN

    Institute of Scientific and Technical Information of China (English)

    Mousa Yousefi; Ziaddin Daie Koozehkanani; Jafar Sobhi; Hamid Jangi

    2014-01-01

    ⎯A 2.4 GHz high efficiency radio frequency (RF) transmitter for wireless body area network (WBAN) in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is proposed to achieve a high data rate with low power consumption. In conventional transmitters, the oscillator and power amplifier are turned off when the transmitter sends 0. The required time for turning oscillator ON/OFF is longer than the other blocks of the transmitter. In the proposed transmitter, the low power oscillator is on all the time while the power amplifier and modulator are turned off when“0”data is sent. The transmitter consumes 3.2 mW at 0.5 dBm output by 285 Mbps data rate and the energy consumption per transmitted bit with 0.5 dBm output power is 10 pJ/(bit⋅mW). The proposed transmitter was designed in 0.18 µm CMOS technology.

  7. Solar radio-transmitters on snail kites in Florida

    Science.gov (United States)

    Snyder, N.F.R.; Beissinger, S.R.; Fuller, M.R.

    1989-01-01

    The effectiveness and safety of one- and two-stage solar radio-transmitters in tracking the movements and survival of adult and fledgling Snail Kites (Rostrhamus sociabilis) were evaluated between 1979 and 1983 in southern Florida. Transmitters were attached to birds with back-pack arrangements using teflon ribbon straps. Accessory plastic shields minimized feather coverage of the solar cells. Intact transmitters were seen on birds up to 47 mo after installation. Operating lives ranged from 8 to 21 mo for one-stage, and 10 to 14 mo for two-stage transmitters. Because survival of adult and nestling radio-marked kites was high, we conclude that our transmitter-attachment method had little effect on the birds.

  8. Variable angle transmittance of silver grid transparent electrodes

    Science.gov (United States)

    Zhao, Yuan-Yuan; Zheng, Mei-Ling; Dong, Xian-Zi; Zhao, Zhen-Sheng; Duan, Xuan-Ming

    2016-10-01

    We focus on investigating the optical transmittance of silver grid transparent electrodes (SGTEs) in variable angle view theoretically and experimentally, rather than the optical transmittance under the normal incidence. The variable angle transmittance (VAT) values of SGTEs are measured on a home-made experimental setup. The experimental results about difference of the transmittance difference under different angles are small and negligible, although the measured angle is changed. Theoretically, the physical mechanism on nearly constant transmittance for different angle view can be well explained according to the theory of geometrical optics. This study provides an approach for investigating the VAT values of SGTEs in a controllable fashion and the influence of viewing angle of the touch screen.

  9. 47 CFR 90.473 - Operation of internal transmitter control systems through licensed fixed control points.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Operation of internal transmitter control... Transmitter Control Internal Transmitter Control Systems § 90.473 Operation of internal transmitter control systems through licensed fixed control points. An internal transmitter control system may be...

  10. A small long-life acoustic transmitter for studying the behavior of aquatic animals

    Science.gov (United States)

    Lu, J.; Deng, Z. D.; Li, H.; Myjak, M. J.; Martinez, J. J.; Xiao, J.; Brown, R. S.; Cartmell, S. S.

    2016-11-01

    Acoustic telemetry is an important tool for studying the behavior of aquatic animals and assessing the environmental impact of structures such as hydropower facilities. However, the physical size, signal intensity, and service life of off-the-shelf transmitters are presently insufficient for monitoring certain species. In this study, we developed a small, long-life acoustic transmitter with an approximate length of 24.2 mm, diameter of 5.0 mm, and dry weight of 0.72 g. The transmitter generates a coded acoustic signal at 416.7 kHz with a selectable source level between 159 and 163 dB relative to 1 μPa at 1 m, allowing a theoretical detection range of up to 500 m. The expected operational lifetime is 1 yr at a pulse rate interval of 15 s. The new technology makes long-term acoustic telemetry studies of small fish possible, and is being deployed for a long-term tracking of juvenile sturgeon.

  11. A simple mixture to enhance muscle transmittance

    Science.gov (United States)

    Oliveira, Luís; Lage, Armindo; Clemente, Manuel Pais; Tuchin, Valery V.

    2008-06-01

    Skeletal muscle is a fibrous tissue composed by muscle fibers and interstitial fluid. Due to this constitution, the muscle presents a non uniform refractive index profile that origins strong light scattering. One way to improve tissue transmittance is to reduce this refractive index mismatch by immersing the muscle in an optical clearing agent. As a consequence of such immersion tissue also suffers dehydration. The study of the optical clearing effect created by a simple mixture composed by ethanol, glycerol and distilled water has proven its effectiveness according to the variations observed in the parameters under study. The effect was characterized in terms of its magnitude, time duration and histological variations. The applied treatment has created a small reduction of the global sample refractive index that is justified by the long time rehydration caused by water in the immersing solution. From the reduction in sample pH we could also identify the dehydration process created in the sample. The immersion treatment has originated fiber bundle contraction and a spread distribution of the muscle fiber bundles inside. New studies with the mixture used, or with other combinations of its constituents might be interesting to perform with the objective to develop new clinical procedures.

  12. Flexible, reconfigurable, power efficient transmitter and method

    Science.gov (United States)

    Bishop, James W. (Inventor); Zaki, Nazrul H. Mohd (Inventor); Newman, David Childress (Inventor); Bundick, Steven N. (Inventor)

    2011-01-01

    A flexible, reconfigurable, power efficient transmitter device and method is provided. In one embodiment, the method includes receiving outbound data and determining a mode of operation. When operating in a first mode the method may include modulation mapping the outbound data according a modulation scheme to provide first modulation mapped digital data, converting the first modulation mapped digital data to an analog signal that comprises an intermediate frequency (IF) analog signal, upconverting the IF analog signal to produce a first modulated radio frequency (RF) signal based on a local oscillator signal, amplifying the first RF modulated signal to produce a first RF output signal, and outputting the first RF output signal via an isolator. In a second mode of operation method may include modulation mapping the outbound data according a modulation scheme to provide second modulation mapped digital data, converting the second modulation mapped digital data to a first digital baseband signal, conditioning the first digital baseband signal to provide a first analog baseband signal, modulating one or more carriers with the first analog baseband signal to produce a second modulated RF signal based on a local oscillator signal, amplifying the second RF modulated signal to produce a second RF output signal, and outputting the second RF output signal via the isolator. The digital baseband signal may comprise an in-phase (I) digital baseband signal and a quadrature (Q) baseband signal.

  13. Piezoelectric transducer design for a miniaturized injectable acoustic transmitter

    Science.gov (United States)

    Li, H.; Jung, K. W.; Deng, Z. D.

    2015-11-01

    Implantable acoustic transmitters have been used in the last 20 years to track fish movement for fish survival and migration behavior studies. However, the relatively large weights and sizes of commercial transmitters limit the populations of studied fish. The surgical implantation procedures may also affect fish adversely and incur a significant amount of labor. Therefore, a smaller, lighter, and injectable transmitter was needed, and similar or better acoustic performance and service life over those provided by existing commercial transmitters was desired. To develop such a small transmitter, a number of technical challenges, including design optimization of the piezoelectric transducer, needed to be overcome. Our efforts to optimize the transducer focused on improving the average source level in the 180° range in which the signal was not blocked by the transmitter body. We found that a novel off-center tube transducer improved the average source level by 1.5 dB. An acoustic reflector attached to the back of the transducer also improved the source level by 1.3 dB. We found that too small a gap between the transducer and the component placed behind it resulted in distortion of the beam pattern. Lastly, a tuning inductor in series with the transducer was used to help optimize the source level. The findings and techniques developed in this work contributed to the successful development and implementation of a new injectable transmitter.

  14. ELF/VLF wave disturbances detected by the DEMETER satellite over the HAARP transmitter

    Science.gov (United States)

    Titova, Elena; Demekhov, Andrei; Parrot, Michel; Mogilevsky, Mikhail; Mochalov, Alexey; Pashin, Anatoly

    We report observations of electromagnetic the ELF/VLF wave disturbances by the DEMETER satellite (670 km altitude) overflying the HAARP heating facility (62.39(°) N, 145.15(°) W, L = 4.9). The HAARP HF transmitter operated at the maximum available power of 3.6 MW, O-mode polarization, and the beam directed towards the magnetic zenith. ELF/VLF waves caused by the HAARP heating are detected by the DEMETER satellite when the HF radio wave frequency was close to the critical frequency (foF2) of the ionospheric F2 layer but below it. ELF/VLF wave disturbances observed above the HAARP transmitter were detected by electrical antennas in an area with characteristic size 10 (2) km. We analyze amplitude and polarization spectra of the ELF disturbances and compare them with the characteristics of natural ELF hiss above HAARP. The VLF wave disturbances in the topside ionosphere above the HAARP transmitter were detected in the frequency ranges 8-17 kHz and 15-18 kHz which are close to the lower hybrid resonance frequency f _LHR in the heating region and its second harmonic (2f _LHR), respectively. In the case where the HAARP HF power was modulated, the detected VLF waves were also modulated with the same frequency whereas in the ELF frequency range the modulation period of the HAARP power was not observed. Possible mechanisms of generation of the ELF/VLF disturbances produced by the HAARP transmitter in the topside ionosphere are discussed.

  15. Combined operation of two ground transmitters for enhanced ionospheric heating

    Science.gov (United States)

    Lee, M. C.; Groves, K. M.; Liao, C. P.; Rivas, D. R.; Kuo, S. P.

    1988-01-01

    The combined operation of a high or medium frequency ground transmitter and a VLF transmitter for enhanced ionospheric heating is examined. The high or medium frequency transmitter operating in a pulsed mode produce short-scale density striations that can render the nonlinear mode conversion of the subsequently launched VLF waves into lower hybrid waves. Also if the VLF waves are intense enough, they can excite meter-scale density striations and lower hybrid waves via parametric instabilities. The expected ionospheric effects of the system are discussed.

  16. Thermal Design and Flight Validation for Solid-state Transmitter

    OpenAIRE

    Wang Lei; Wen Yao-pu

    2014-01-01

    Solid-state transmitter with large power and high heat flux is a key equipment of an HJ-1-C satellite; therefore, it has a great influence on satellite thermal design. Thermal design ensures that the solid-state transmitter works well within the allowable temperature limits of the equipment. The solid-state transmitter thermal design and solved key problems are provided in accordance with the HJ-1-C characteristics. Moreover, an analysis of satellites on orbit was performed. Based on the tele...

  17. Intelligent Industrial Transmitters of Pressure and Other Process Parameters

    Directory of Open Access Journals (Sweden)

    B. L. Miljković

    2009-11-01

    Full Text Available An overview is given of industrial measurement instruments (transmitters of pressure and other process parameters. It is followed by a description of the technology used in the current generation of intelligent transmitters featuring two-way digital communication. A recently developed product of IHTM–CMTM, the intelligent pressure transmitter is presented, including a description of the software temperature compensation method for the used pressure sensor. Features and application possibilities of the developed hardware and software platform are discussed, as well as its suitability for the realization of wireless sensors.

  18. Transmitter antenna placement in indoor environments using particle swarm optimisation

    Science.gov (United States)

    Talepour, Zeinab; Tavakoli, Saeed; Ahmadi-Shokouh, Javad

    2013-07-01

    The aim of this article is to suitably locate the minimum number of transmitter antennas in a given indoor environment to achieve good propagation coverage. To calculate the electromagnetic field in various points of the environment, we develop a software engine, named ray-tracing engine (RTE), in Matlab. To achieve realistic calculations, all parameters of geometry and material of building are considered. Particle swarm optimisation is employed to determine good location of transmitters. Simulation results show that a full coverage is obtained through suitably locating three transmitters.

  19. Streaming Transmitter over Block-Fading Channels with Delay Constraint

    CERN Document Server

    Cocco, Giuseppe; Ibars, Christian

    2012-01-01

    Data streaming transmission, in which the data arrives at the transmitter gradually over time is studied. It is assumed that the transmitter receives a new message at each channel block at a constant rate which is fixed by an underlying application, and tries to broadcast these messages to users within a certain deadline. The channels are assumed to be block fading and independent over blocks and users. The performance measure is the average total rate of received information at the users within the transmission deadline. Three different encoding schemes are proposed and compared with an informed transmitter upper bound in terms of the average total rate for a set of users with varying channel qualities. Analytical upper bounds on the average total rate are derived for all the proposed schemes. It is shown that no single transmission strategy dominates the others at all channel settings, and the best transmitter streaming scheme depends on the distribution of the average channel conditions over the users.

  20. High Temperature Telemetry Transmitter for Venus Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed S-band telemetry transmitter will operate in the exterior Venusian corrosive, high pressure, 460oC ambient atmosphere without being contained in a...

  1. High Temperature Telemetry Transmitter for Venus Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed S-band telemetry transmitter will operate in the exterior Venusian high pressure, 465?aC ambient atmosphere without being contained in a thermally...

  2. Efficient and Compact Semiconductor Laser Transmitter Modules Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Continue development of a Compact Transmitter Module (CTM). Modules will be voltage controlled to adjust wavlength using temperature and drive current settings. The...

  3. Television Transmitter Locations, Published in Not Provided, US Army.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Television Transmitter Locations dataset as of Not Provided. Data by this publisher are often provided in Not Applicable coordinate system; in a Not Applicable...

  4. Compressed Sensing Based Fingerprint Identification for Wireless Transmitters

    Directory of Open Access Journals (Sweden)

    Caidan Zhao

    2014-01-01

    Full Text Available Most of the existing fingerprint identification techniques are unable to distinguish different wireless transmitters, whose emitted signals are highly attenuated, long-distance propagating, and of strong similarity to their transient waveforms. Therefore, this paper proposes a new method to identify different wireless transmitters based on compressed sensing. A data acquisition system is designed to capture the wireless transmitter signals. Complex analytical wavelet transform is used to obtain the envelope of the transient signal, and the corresponding features are extracted by using the compressed sensing theory. Feature selection utilizing minimum redundancy maximum relevance (mRMR is employed to obtain the optimal feature subsets for identification. The results show that the proposed method is more efficient for the identification of wireless transmitters with similar transient waveforms.

  5. High-power solid-state microwave transmitter

    Science.gov (United States)

    Boreham, J. D.; Conroy, B. L.; Postal, R. B.; Yenche, D. G.

    1981-01-01

    Transmitter phases outputs from individual amplifier modules then combines them in multielement array feed antenna. Size and power capability of system are variable for radar and small-angle scanning applications.

  6. 47 CFR 95.855 - Transmitter effective radiated power limitation.

    Science.gov (United States)

    2010-10-01

    ... Transmitter effective radiated power limitation. The effective radiated power (ERP) of each CTS and RTU shall... with an ERP exceeding 20 watts. No mobile RTU may transmit with an ERP exceeding 4 watts....

  7. Testing tail-mounted transmitters with Myocastor coypus (nutria)

    Science.gov (United States)

    Merino, S.; Carter, J.; Thibodeaux, G.

    2007-01-01

    We developed a tail-mounted radio-transmitter for Myocastor coypus (nutria) that offers a practical and efficient alternative to collar or implant methods. The mean retention time was 96 d (range 57-147 d, n = 7), making this a practical method for short-term studies. The tail-mounts were less injurious to animals than collars and easier for field researchers to implement than either collars or surgically implanted transmitters.

  8. Reflectance and transmittance model for recto-verso halftone prints

    OpenAIRE

    Hebert, M.; R. D. Hersch

    2006-01-01

    We propose a spectral prediction model for predicting the reflectance and transmittance of recto-verso halftone prints. A recto-verso halftone print is modeled as a diffusing substrate surrounded by two inked interfaces in contact with air (or with another medium). The interaction of light with the print comprises three components: (a) the attenuation of the incident light penetrating the print across the inked interface, (b) the internal reflectance and internal transmittance that accounts f...

  9. Photonic integrated transmitter and receiver for NG-PON2

    Science.gov (United States)

    Tavares, Ana; Lopes, Ana; Rodrigues, Cláudio; Mãocheia, Paulo; Mendes, Tiago; Brandão, Simão.; Rodrigues, Francisco; Ferreira, Ricardo; Teixeira, António

    2014-08-01

    In this paper the authors present a monolithic Photonic Integrated Circuit which includes a transmitter and a receiver for NG-PON2. With this layout it is possible to build an OLT and, by redesigning some filters, also an ONU. This technology allows reducing the losses in the transmitter and in the receiver, increasing power budget, and also reducing the OEO conversions, which has been a major problem that operators want to surpass.

  10. Effects of radio transmitters on migrating wood thrushes

    Science.gov (United States)

    Powell, L.A.; Krementz, D.G.; Lang, J.D.; Conroy, M.J.

    1998-01-01

    We quantified the effects of radio transmitters on Wood Thrushes (Hylocichla mustelina) using 4 yr of banding and telemetry data from Piedmont National Wildlife Refuge, Georgia. Flight performance models suggest that the 1.6-g transmitter shortens the migratory range of Wood Thrushes by only 60 km, and the estimated migratory range is adequate to accomplish migration even with limited fat stores. We used two strengths of line, 5- and 9-kg test-strength braided Dacron, to attach the transmitters using the thigh-harness method. We recaptured 13 returning radio-marked Wood Thrushes, seven of which were still marked. Six of the seven birds marked with the 5-kg test harnesses lost their transmitters within 1 yr while all six of the 9-kg test harnesses were still attached up to 21 mo later. Radio-marking did not reduce the return rates of adults and immatures, and the transmitters did not cause radio-marked birds to lose more mass than banded-only birds. Wood Thrushes can successfully carry a transmitter during migration with no detectable negative effects. We recommend continued use of the thigh-harness method, but we encourage the use of 5-kg cotton line.

  11. Modeling and compensation of transmitter nonlinearity in coherent optical OFDM.

    Science.gov (United States)

    Amiralizadeh, Siamak; Nguyen, An T; Rusch, Leslie A

    2015-10-05

    We present a comprehensive study of nonlinear distortions from an optical OFDM transmitter. Nonlinearities are introduced by the combination of effects from the digital-to-analog converter (DAC), electrical power amplifier (PA) and optical modulator in the presence of high peak-to-average power ratio (PAPR). We introduce parameters to quantify the transmitter nonlinearity. High input backoff avoids OFDM signal compression from the PA, but incurs high penalties in power efficiency. At low input backoff, common PAPR reduction techniques are not effective in suppressing the PA nonlinear distortion. A bit error distribution investigation shows a technique combining nonlinear predistortion with PAPR mitigation could achieve good power efficiency by allowing low input backoff. We use training symbols to extract the transmitter nonlinear function. We show that piecewise linear interpolation (PLI) leads to an accurate transmitter nonlinearity characterization. We derive a semi-analytical solution for bit error rate (BER) that validates the PLI approximation accurately captures transmitter nonlinearity. The inverse of the PLI estimate of the nonlinear function is used as a predistorter to suppress transmitter nonlinearity. We investigate performance of the proposed scheme by Monte Carlo simulations. Our simulations show that when DAC resolution is more than 4 bits, BER below forward error correction limit of 3.8 × 10(-3) can be achieved by using predistortion with very low input power backoff for electrical PA and optical modulator.

  12. UV transmittance during the crosslinking procedure: tunable treatment

    Science.gov (United States)

    Lincoln, Victor A. C.; Mello, Marcio M.; Ventura, Liliane

    2014-02-01

    The transmittance of UVA light through the in vitro human cornea over the thickness of 400um during the corneal collagen cross-linking procedure has been measured using an optical fiber (600 μm core diameter) fixed just before the cornea and attached to Spectrophotometer. The 10 corneas, (average of 6 days post-mortem) were washed with saline and cross-linked with the currently used protocol. To enhance absorption of UV radiation, Riboflavin solution (0.1% and 400 mOsm) was applied prior to and during exposure. The UVA beam - 365nm +/- 5nm at 3mW/cm2 +/- 0.003mW/cm2 - was focused directly onto the corneal stroma. The measured average transmittance of the cornea without Riboflavin was 64.1%. Preceding the irradiation but after 6 applications of Riboflavin at 5min intervals (total of 30min) transmittance decreased to 21.1%. The 30min of irradiation were then accompanied by an additional 6 applications of Riboflavin at 5min intervals (for a total of treatment time of 1h), resulting in a further decrease in transmittance to 12.2%, which is in agreement with current literature. The average transmittance in terms of energy during the 30 minutes irradiation procedure fluctuated from 0.63 to 0.37 mW/cm2. These results indicate different levels of UV transmittance during treatment, leading to consider a new personalized treatment with tunable UV power irradiation.

  13. Ultraviolet absorption and epidermal-transmittance spectra in foliage

    Energy Technology Data Exchange (ETDEWEB)

    Day, T.A.; Howells, B.W.; Rice, W.J. (Dept. of Biology, West Virginia Univ., Morgantown, WV (United States))

    1994-01-01

    We examined the UV absorption spectra and the epidermal-transmittance spectra (280-350 nm) of foliage from 42 plant species. Sun foliage was sampled from naturally growing individuals of seven species in each of six life forms comprising two evergreen groups (gymnosperms and angiosperms) and four deciduous angiosperm groups (trees, shrubs and vines, herbaceous dicotyledons and grasses). There were large differences in absorption spectra of whole-leaf extracts among species. While absorbance declined with increasing wavelength in most woody species, there was a through in absorbance around 300 nm in many herbaceous species. Absorption spectra were negatively correlated with epidermal-transmittance spectra in 31 of the 42 species. Relationships between absorbance and transmittance did not follow the theoretical exponential function. Species rankings of UV-screening effectiveness were similar when we assessed it by using epidermal transmittance at single wavelengths (300 or 320 nm) or different UV-action spectra to weight epidermal-transmittance spectra and estimate the levels of biologically effective UV reaching the mesophyll. Thus, differences in absolute epidermal transmittance among species appeared to overshadow spectral differences. Nevertheless, the differences we found in the internal UV spectral regime in foliage suggest that whole-plant action spectra will differ among species. While species rankings of UV-screening effectiveness were similar when different action spectra were used, the absolute amounts of biologically effective UV reaching the mesophyll of species varied considerably when different action spectra were used. (au) (46 refs.)

  14. The perceived transmittance of inhomogeneous surfaces and media.

    Science.gov (United States)

    Anderson, Barton L; Singh, Manish; Meng, Jeanette

    2006-06-01

    A series of experiments was performed to determine how the visual system computes the transmittance of inhomogeneous surfaces and media. Previous work (Anderson, B. L. (1999) Stereoscopic surface perception. Neuron, 26, 919-928; Anderson, B. L. (2003) The role of occlusion in the perception of depth, lightness, and opacity. Psychological Review, 110, 762-784) has suggested that the visual system employs a transmittance anchoring principle in determining when transparency is perceived. This principle states that the visual system interprets the highest contrast region along contours and surfaces as a region in plain view and uses this anchor as a reference point for transparency computations. In particular, recent work has shown that the transmittance of homogeneous transparent surfaces is well described by a ratio of contrasts model (Singh, M., & Anderson, B. L. (2002). Toward a perceptual theory of transparency. Psychological Review, 109, 492-519). In this model, the transmittance of a transparent surface is determined by the contrast of a transparent image region normalized by the contrast of the region in plain view. Here, a series of experiments is reported that assesses this model for inhomogeneous transparent surfaces that vary in both space and time. The results of these experiments reveal that transmittance anchoring has both a spatial and temporal component, and that the perceived transmittance of transparent surfaces is well described by a ratio of perceived contrasts model.

  15. 47 CFR 22.573 - Use of base transmitters as repeaters.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Use of base transmitters as repeaters. 22.573... of base transmitters as repeaters. As an additional function, base transmitters may be used as repeaters. Licensees must be able to turn the base transmitter on or off from the control point...

  16. 47 CFR 90.475 - Operation of internal transmitter control systems in specially equipped systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Operation of internal transmitter control... Control Internal Transmitter Control Systems § 90.475 Operation of internal transmitter control systems in specially equipped systems. (a) An internal transmitter control system need not be designed to meet...

  17. Facilities & Leadership

    Data.gov (United States)

    Department of Veterans Affairs — The facilities web service provides VA facility information. The VA facilities locator is a feature that is available across the enterprise, on any webpage, for the...

  18. Biochemistry Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Biochemistry Facility provides expert services and consultation in biochemical enzyme assays and protein purification. The facility currently features 1) Liquid...

  19. Effects of radio transmitters on nesting captive mallards

    Science.gov (United States)

    Houston, Robert A.; Greenwood, Raymond J.

    1993-01-01

    Radio packages may subtly affect bird behavior and condition, and thus could bias results from studies using this technique. To assess effects on reproduction of mallards (Anas platyrhynchos), we tested 3 types of back-mounted radio packages on captive females. Eight paired females were randomly assigned to each of 4 treatments: 4-g transmitter attached with sutures and glue, 10-g or 18-g transmitter attached with a harness, and no transmitter (control). All mallards were fed ad libitum. No differences were detected among treatments in number of clutches, clutch size, nesting interval, egg mass, or body mass; powers (range = 0.15-0.48) of tests were low. Feather wear and skin irritation around radio packages were minimal. Birds retained sutured transmitters for an average of 43.5 days (range = 3-106 days) and harness transmitters for the duration of the study (106 days). Sutures were not reliable and presently are not recommended as an attachment method. Caution is advised in applying these results to radio-equipped mallards in the wild.

  20. A taping method for external transmitter attachment on aquatic snakes

    Science.gov (United States)

    Wylie, G.D.; Smith, J.J.; Amarello, M.; Casazza, M.L.

    2011-01-01

    Radio telemetry is extremely useful for studying habitat use and movements of free ranging snakes. Surgically implanting radio transmitters into the body cavity of snakes is standard practice in most studies (e.g., Reinert and Cundall 1982; Weatherhead and Blouin-Demers 2004), but this implanting method has its drawbacks. Surgery itself is risky for individual snakes because of the potential for infection or incomplete healing of the incision site. Also, transmitters that are small enough to be carried by small or slender snakes have a relatively short battery life and need to be removed or replaced often, thus requiring frequent surgeries. In rare or endangered snake species, the risk of using invasive implantation surgery may not be merited. External attachment methods are relatively non-invasive and allow removal and replacement of radio transmitters on smaller snakes. The Giant Gartersnake (Thamnophis gigas) is a semi-aquatic snake endemic to wetlands of the Central Valley of California, USA, and is federally and state listed as threatened (U.S. Fish and Wildlife Service 1999). Telemetry studies of the habitat use and movements of this species typically used surgically implanted radio transmitters, but this method is limited to larger snakes, primarily females, because of size requirements for surgery (> 250 g). To overcome difficulties and biases associated with radio telemetry of T. gigas, we developed and evaluated several alternative techniques to attach external radio transmitters using tape.

  1. An Energy Harvesting Underwater Acoustic Transmitter for Aquatic Animals

    Science.gov (United States)

    Li, Huidong; Tian, Chuan; Lu, Jun; Myjak, Mitchell J.; Martinez, Jayson J.; Brown, Richard S.; Deng, Zhiqun Daniel

    2016-09-01

    Acoustic telemetry is the primary method to actively track aquatic animals for behavioral studies. However, the small storage capacities of the batteries used in the transmitters limit the time that the implanted animals can be studied. In this research, we developed and implemented a battery-free acoustic transmitter that uses a flexible piezoelectric beam to harvest energy from fish swimming as the power source. The transmitter sends out a unique identification code with a sufficiently strong signal (150 dB, ref: 1 μPa at 1 meter) that has a detection range of up to 100 meters. Two prototypes, 100 mm and 77 mm long, respectively, weighing only about 1 gram or less in air, were sub-dermally implanted in two species of live fish. Transmissions were successfully detected as the fish swam in a natural manner. This represents the first known implanted energy-harvesting transmitter demonstrated in vivo. Successful development of this transmitter greatly expands the potential for long-term studies of the behaviors of aquatic animals and for subsequently developing strategies to mitigate the environmental impacts of renewable energy systems.

  2. An Energy Harvesting Underwater Acoustic Transmitter for Aquatic Animals

    Science.gov (United States)

    Li, Huidong; Tian, Chuan; Lu, Jun; Myjak, Mitchell J.; Martinez, Jayson J.; Brown, Richard S.; Deng, Zhiqun Daniel

    2016-01-01

    Acoustic telemetry is the primary method to actively track aquatic animals for behavioral studies. However, the small storage capacities of the batteries used in the transmitters limit the time that the implanted animals can be studied. In this research, we developed and implemented a battery-free acoustic transmitter that uses a flexible piezoelectric beam to harvest energy from fish swimming as the power source. The transmitter sends out a unique identification code with a sufficiently strong signal (150 dB, ref: 1 μPa at 1 meter) that has a detection range of up to 100 meters. Two prototypes, 100 mm and 77 mm long, respectively, weighing only about 1 gram or less in air, were sub-dermally implanted in two species of live fish. Transmissions were successfully detected as the fish swam in a natural manner. This represents the first known implanted energy-harvesting transmitter demonstrated in vivo. Successful development of this transmitter greatly expands the potential for long-term studies of the behaviors of aquatic animals and for subsequently developing strategies to mitigate the environmental impacts of renewable energy systems. PMID:27647426

  3. Robust Beamforming in Interference Channels with Imperfect Transmitter Channel Information

    CERN Document Server

    Mochaourab, Rami

    2011-01-01

    We consider $K$ links operating concurrently in the same spectral band. Each transmitter has multiple antennas, while each receiver uses a single antenna. This setting corresponds to the multiple-input single-output interference channel. We assume perfect channel state information at the receivers whereas the transmitters only have estimates of the true channels. The channel estimation errors are assumed to be bounded in elliptical regions whose geometry is known at the transmitters. Robust beamforming optimizes worst-case received power gains, and a Pareto optimal point is a worst-case achievable rate tuple from which it is impossible to increase a link's performance without degrading the performance of another. We characterize the robust beamforming vectors necessary to operate at any Pareto optimal point. Moreover, these beamforming vectors are parameterized by $K(K-1)$ real-valued parameters. We analyze the system's spectral efficiency at high and low signal-to-noise ratio (SNR). Zero forcing transmission...

  4. Joint Transmitter-Receiver Optimization in the Downlink CDMA Systems

    Directory of Open Access Journals (Sweden)

    Mohammad Saquib

    2002-08-01

    Full Text Available To maximize the downlink code-division multiple access (CDMA system capacity, we propose to minimize the total transmitted power of the system subject to users′ signal-to-interference ratio (SIR requirements via designing optimum transmitter sequences and utilizing linear optimum receivers (minimum mean square error (MMSE receiver. In our work on joint transmitter-receiver design for the downlink CDMA systems with multiple antennas and multipath channels, we develop several optimization algorithms by considering various system constraints and prove their convergence. We empirically observed that under the optimization algorithm with no constraint on the system, the optimum receiver structure matches the received transmitter sequences. A simulation study is performed to see how the different practical system constraints penalize the system with respect to the optimum algorithm with no constraint on the system.

  5. Experimental Realization of Tunable Metamaterial Hyper-transmitter

    Science.gov (United States)

    Yoo, Young Joon; Yi, Changhyun; Hwang, Ji Sub; Kim, Young Ju; Park, Sang Yoon; Kim, Ki Won; Rhee, Joo Yull; Lee, YoungPak

    2016-01-01

    We realized the tunable metamaterial hyper-transmitter in the microwave range utilizing simple planar meta-structure. The single-layer metamaterial hyper-transmitter shows that the transmission peak occurs at 14 GHz. In case of the dual-layer one, it is possible to control the transmission peak from 5 to 10 GHz. Moreover, all the transmission peaks reveal transmission over 100%. We experimentally and theoretically investigated these phenomena through 3-dimensional simulation and measurement. The reason for being over 100% is also elucidated. The suggested hyper-transmitter can be used, for example, in enhancing the operating distance of the electromagnetic wave in Wi-Fi, military radar, wireless power transfer and self-driving car. PMID:27629804

  6. Experimental Realization of Tunable Metamaterial Hyper-transmitter

    Science.gov (United States)

    Yoo, Young Joon; Yi, Changhyun; Hwang, Ji Sub; Kim, Young Ju; Park, Sang Yoon; Kim, Ki Won; Rhee, Joo Yull; Lee, Youngpak

    2016-09-01

    We realized the tunable metamaterial hyper-transmitter in the microwave range utilizing simple planar meta-structure. The single-layer metamaterial hyper-transmitter shows that the transmission peak occurs at 14 GHz. In case of the dual-layer one, it is possible to control the transmission peak from 5 to 10 GHz. Moreover, all the transmission peaks reveal transmission over 100%. We experimentally and theoretically investigated these phenomena through 3-dimensional simulation and measurement. The reason for being over 100% is also elucidated. The suggested hyper-transmitter can be used, for example, in enhancing the operating distance of the electromagnetic wave in Wi-Fi, military radar, wireless power transfer and self-driving car.

  7. Examination of an optical transmittance test for photovoltaic encapsulation materials

    Science.gov (United States)

    Miller, David C.; Bengoechea, Jaione; Bokria, Jayesh G.; Köhl, Michael; Powell, Nick E.; Smith, Michael E.; White, Michael D.; Wilson, Helen Rose; Wohlgemuth, John H.

    2013-09-01

    The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and more appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).

  8. Examination of an optical transmittance test for photovoltaic encapsulation materials

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Bengoechea, Jaione; Bokria, Jayesh G.; Köhl, Michael; Powell, Nick E.; Smith, Michael E.; White, Michael D.; Wilson, Helen Rose; Wohlgemuth, John H.; Dhere, Neelkanth G.; Wohlgemuth, John H.; Lynn, Kevin W.

    2013-09-24

    The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and more appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).

  9. Transmittance jump in a thin aluminium layer during laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Bykovsky, N E; Senatsky, Yu V [P N Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Pershin, S M; Samokhin, A A [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2016-02-28

    A jump in the transmittance (from ∼0.1% to ∼50% for ∼1 ns) of an optical gate on a Mylar film (a thin aluminium layer on a Lavsan substrate) irradiated by nanosecond (10{sup -7} – 10{sup -8} s) pulses of a neodymium laser with an intensity up to 0.1 GW cm{sup -2} has been recorded. The mechanism of a fast (10{sup -10} – 10{sup -11} s) increase in the transmittance of the aluminium layer upon its overheating (without boiling) to the metal – insulator phase-transition temperature is discussed. (interaction of laser radiation with matter. laser plasma)

  10. On the Capacity of Interference Channels with One Cooperating Transmitter

    CERN Document Server

    Maric, I; Krämer, G; Shamai, S

    2007-01-01

    Inner and outer bounds are established on the capacity region of two-sender, two-receiver interference channels where one transmitter knows both messages. The transmitter with extra knowledge is referred to as being cognitive. The inner bound is based on strategies that generalize prior work, and include rate-splitting, Gel'fand-Pinsker coding and cooperative transmission. A general outer bound is based on the Nair-El Gamal outer bound for broadcast channels. A simpler bound is presented for the case in which one of the decoders can decode both messages. The bounds are evaluated and compared for Gaussian channels.

  11. Transmittance characteristics of plasmonic graphene ribbons with a wing

    Science.gov (United States)

    Yuan, Lin; Yan, Xin; Wang, Yueke; Sang, Tian; Yang, Guofeng

    2016-09-01

    We numerically investigate the transmittance characteristics of graphene ribbons with a wing by the finite element method. By determining the dispersion relation of edge graphene plasmon (EGP) modes and analyzing the mode distributions, it is considered that the transmission dips originate from the resonances of three EGP modes, namely, the symmetrical EGPs, antisymmetrical EGPs, and EGPs of a semi-infinite sheet. By changing the width and length of the wing, it was further confirmed that transmission dips originate from the EGP modes. Owing to the tunable permittivity of graphene by adjusting the gate voltage, the transmittance dips can be easily tuned.

  12. Transmittance characteristics and tunable sensor performances of plasmonic graphene ribbons

    Science.gov (United States)

    Yan, Xin; Yuan, Lin; Wang, Yueke; Sang, Tian; Yang, Guofeng

    2016-08-01

    We investigate the transmittance characteristics of graphene ribbons numerically. It is found that the transmission dips originate from the transverse and longitudinal resonances of edge graphene plasmon modes, supported by the graphene ribbon resonator. The environmental refractive index changes are detected by measuring the resulting spectral shifts of the resonant transmission dip, so the graphene ribbons can be applied to plasmonic sensor in infrared. Simulation results show that sensing performances for each resonant mode are similar, and figure of merit can be up to 6. Beside, thanks to the tunable permittivity of graphene by bias voltages, the transmittance spectra and sensor performances can be easily tuned.

  13. RF-modulated pulsed fiber optic lidar transmitter for improved underwater imaging and communications

    Science.gov (United States)

    Kimpel, F.; Chen, Y.; Fouron, J.-L.; Akbulut, M.; Engin, D.; Gupta, S.

    2011-03-01

    We present results on the design, development and initial testing of a fiber-optic based RF-modulated lidar transmitter operating at 532nm, for underwater imaging application in littoral waters. The design implementation is based on using state-of-the-art high-speed FPGAs, thereby producing optical waveforms with arbitrary digital-RF-modulated pulse patterns with carrier frequencies >= 3GHz, with a repetition rate of 0.5-1MHz, and with average powers >=5W (at 532nm). Use of RF-modulated bursts above 500MHz, instead of single optical pulse lidar detection, reduces the effect of volumetric backscatter for underwater imaging application, leading to an improved signal-to-noise-ratio (SNR) and contrast, for a given range. Initial underwater target detection tests conducted at Patuxent River Naval Air Station, MD, in a large water-tank facility, validates the advantages of this hybrid-lidar-radar (HLR) approach for improved underwater imaging, over a wide range of turbidity levels and both white and black targets. The compact, robust and power-efficient fiber laser architecture lends very well to lidar sensor integration on unmanned-underwater-vehicle (UUV) platforms. HLR transmitters can also provide similar advantages in active-sensing situations dominated by continuous backscatter, e.g. underwater communications, imaging through smoke and fire environment, rotor-craft landing in degraded visual environment, and pointing-tracking of active-EO sensors through fog.

  14. Efficient and Compact Semiconductor Laser Transmitter Modules Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop a Compact Transmitter Module (CTM) capable of operating at 1.26 5m, 1.57 5m and at 2 5m complete with all drive and control electronics for the TEC and the...

  15. 22 CFR 181.7 - Transmittal to the Congress.

    Science.gov (United States)

    2010-04-01

    ... Assistant Legal Adviser for Treaty Affairs to the Senate Committee on Foreign Affairs. ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Transmittal to the Congress. 181.7 Section 181.7 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL AGREEMENTS COORDINATION, REPORTING AND...

  16. Mark 4A DSN receiver-exciter and transmitter subsystems

    Science.gov (United States)

    Wick, M. R.

    1986-01-01

    The present configuration of the Mark 4A DSN Receiver-Exciter and Transmitter Subsystems is described. Functional requirements and key characteristics are given to show the differences in the capabilities required by the Networks Consolidation task for combined High Earth Orbiter and Deep Space Network tracking support.

  17. Airborne Measurements of Atmospheric Methane Using Pulsed Laser Transmitters

    Science.gov (United States)

    Numata, Kenji; Riris, Haris; Wu, Stewart; Gonzalez, Brayler; Rodriguez, Michael; Hasselbrack, William; Fahey, Molly; Yu, Anthony; Stephen, Mark; Mao, Jianping; Kawa, Stephan

    2016-01-01

    Atmospheric methane (CH4) is the second most important anthropogenic greenhouse gas with approximately 25 times the radiative forcing of carbon dioxide (CO2) per molecule. At NASA Goddard Space Flight Center (GSFC) we have been developing a laser-based technology needed to remotely measure CH4 from orbit. We report on our development effort for the methane lidar, especially on our laser transmitters and recent airborne demonstration. Our lidar transmitter is based on an optical parametric process to generate near infrared laser radiation at 1651 nanometers, coincident with a CH4 absorption. In an airborne flight campaign in the fall of 2015, we tested two kinds of laser transmitters --- an optical parametric amplifier (OPA) and an optical parametric oscillator (OPO). The output wavelength of the lasers was rapidly tuned over the CH4 absorption by tuning the seed laser to sample the CH4 absorption line at several wavelengths. This approach uses the same Integrated Path Differential Absorption (IPDA) technique we have used for our CO2 lidar for ASCENDS. The two laser transmitters were successfully operated in the NASAs DC-8 aircraft, measuring methane from 3 to 13 kilometers with high precision.

  18. Improved transmittance measurement with a magnesium oxide coated integrating sphere

    Science.gov (United States)

    Bowman, R. L.; Spisz, E. W.

    1972-01-01

    Simple and convenient technique has been found for extending transmittance measurement capability of conventional magnesium oxide coated integrating sphere system at low (near ultraviolet) wavelengths. Technique can be used to determine effect of contaminants on window materials and can also be used for measurements on thermal control coatings and telescope mirrors.

  19. Surgical insertion of transmitters and telemetry methods in fisheries research

    DEFF Research Database (Denmark)

    Rub, A. Michelle Wargo; Jepsen, Niels; Liedtke, Theresa L.

    2014-01-01

    implantation procedures for fish. We also intend to provide insight into the unique challenges of field-based aquatic surgical studies. Within this context, 4 aspects of the process for surgical implantation of transmitters in fish (ie, handling, aseptic technique, anesthesia, and implantation...

  20. Spectral transmittance of the spectacle scale of snakes and geckos

    NARCIS (Netherlands)

    Doorn, van K.; Sivak, J.G.

    2015-01-01

    The spectral transmittance of the optical media of the eye plays a substantial role in tuning the spectrum of light available for capture by the retina. Certain squamate reptiles, including snakes and most geckos, shield their eyes beneath a layer of transparent, cornified skin called the ‘spectacle

  1. Snake mortality associated with late season radio-transmitter implantation

    Science.gov (United States)

    D. Craig Rudolph; Shirley J. Burgdorf; Richard R. Schaefer; Richard N. Conner; Robert T. Zappalorth

    1998-01-01

    Radio-telemetry is an increasingly used procedure to obtain data on the biology of free-living snakes (Reinert 1992, 1994). In Texas and Louisiana we have been using the surgical technique of Weatherhead and Anderka (1984) to implant transmitters in timber rattlesnakes (Crotalus horridus) and Louisiana pine snakes (Pituophis melanoleucus...

  2. Simulation on the Final Stage of 44 MHz Transmitter

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>The 44 MHz transmitter will be used to power the 1:1 scale 100 MeV metal proctortype cavity. To improve the stability of the final stage amplifier and to obtain more output power, it is necessary to

  3. 47 CFR 95.629 - LPRS transmitter frequencies.

    Science.gov (United States)

    2010-10-01

    ....629 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Technical Standards § 95.629 LPRS transmitter frequencies. (a....8075 223 216.8125 224 216.8175 225 216.8225 226 216.8275 227 216.8325 228 216.8375 229 216.8425 230...

  4. 47 CFR 22.165 - Additional transmitters for existing systems.

    Science.gov (United States)

    2010-10-01

    ...-ground Radiotelephone Service. Ground stations may be added to Commercial Aviation air-ground systems at... the same channel. This section does not apply to Basic Exchange Telecommunications Radio Systems. (h... 47 Telecommunication 2 2010-10-01 2010-10-01 false Additional transmitters for existing...

  5. High Speed Surface Thermocouples Interface to Wireless Transmitters

    Science.gov (United States)

    2017-03-15

    Transmitters David Patti 1 Item 6: Eric Gingrich, MS-12 1 RD ECOM-TARDEC-RTI-GVPM Russell Robinson, ACO 1 Item 14, Recipient Destinations: Include completed DD...David Patti: david.m.patti4.civ@mail.mil - Russell Robinson, ACO: russell.robinson@dcma.mil - OTIC (mai l 2 hardcopies) : Defense Technical Information

  6. Cavity-Beam-Transmitter Interaction Formula Collection with Derivation

    CERN Document Server

    Tückmantel, J

    2010-01-01

    The fundamental beam-cavity-transmitter relations for accelerating and deflecting/crab cavities are presented for steady state and time-varying situations. For completeness a compact proof of the Panofsky-Wenzel theorem is given and the fundamental beam loading theorem is derived.Also the determination of relative bunch form factors is shown.

  7. Surgical insertion of transmitters and telemetry methods in fisheries research

    DEFF Research Database (Denmark)

    Rub, A. Michelle Wargo; Jepsen, Niels; Liedtke, Theresa L.

    2014-01-01

    ) will be described. Effects of surgical insertion of transmitters (ie, tagging) and aspects of the surgical implantation process where collaboration and professional exchanges among nonveterinarian researchers and veterinarians may be most fruitful will be discussed. Although this report focuses on surgical...

  8. Hydrothermal growth of VO2 nanoplate thermochromic films on glass with high visible transmittance

    Science.gov (United States)

    Zhang, Jiasong; Li, Jingbo; Chen, Pengwan; Rehman, Fida; Jiang, Yijie; Cao, Maosheng; Zhao, Yongjie; Jin, Haibo

    2016-06-01

    The preparation of thermochromic vanadium dioxide (VO2) films in an economical way is of interest to realizing the application of smart windows. Here, we reported a successful preparation of self-assembly VO2 nanoplate films on TiO2-buffered glass by a facile hydrothermal process. The VO2 films composed of triangle-shaped plates standing on substrates exhibit a self-generated porous structure, which favors the transmission of solar light. The porosity of films is easily controlled by changing the concentration of precursor solutions. Excellent thermochromic properties are observed with visible light transmittance as high as 70.3% and solar modulating efficiency up to 9.3% in a VO2 film with porosity of ~35.9%. This work demonstrates a promising technique to promote the commercial utilization of VO2 in smart windows.

  9. The Integral Test Facility Karlstein

    Directory of Open Access Journals (Sweden)

    Stephan Leyer

    2012-01-01

    Full Text Available The Integral Test Facility Karlstein (INKA test facility was designed and erected to test the performance of the passive safety systems of KERENA, the new AREVA Boiling Water Reactor design. The experimental program included single component/system tests of the Emergency Condenser, the Containment Cooling Condenser and the Passive Core Flooding System. Integral system tests, including also the Passive Pressure Pulse Transmitter, will be performed to simulate transients and Loss of Coolant Accident scenarios at the test facility. The INKA test facility represents the KERENA Containment with a volume scaling of 1 : 24. Component heights and levels are in full scale. The reactor pressure vessel is simulated by the accumulator vessel of the large valve test facility of Karlstein—a vessel with a design pressure of 11 MPa and a storage capacity of 125 m3. The vessel is fed by a benson boiler with a maximum power supply of 22 MW. The INKA multi compartment pressure suppression Containment meets the requirements of modern and existing BWR designs. As a result of the large power supply at the facility, INKA is capable of simulating various accident scenarios, including a full train of passive systems, starting with the initiating event—for example pipe rupture.

  10. Fabrication Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Fabrication Facilities are a direct result of years of testing support. Through years of experience, the three fabrication facilities (Fort Hood, Fort Lewis, and...

  11. Facility Microgrids

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Z.; Walling, R.; Miller, N.; Du, P.; Nelson, K.

    2005-05-01

    Microgrids are receiving a considerable interest from the power industry, partly because their business and technical structure shows promise as a means of taking full advantage of distributed generation. This report investigates three issues associated with facility microgrids: (1) Multiple-distributed generation facility microgrids' unintentional islanding protection, (2) Facility microgrids' response to bulk grid disturbances, and (3) Facility microgrids' intentional islanding.

  12. Fabrication of flexible silver nanowire conductive films and transmittance improvement based on moth-eye nanostructure array

    Science.gov (United States)

    Zhang, Chengpeng; Zhu, Yuwen; Yi, Peiyun; Peng, Linfa; Lai, Xinmin

    2017-07-01

    Transparent conductive electrodes (TCEs) are widely used in optoelectronic devices, such as touch screens, liquid-crystal displays and light-emitting diodes. To date, the material of the most commonly used TCEs was indium-tin oxide (ITO), which had several intrinsic drawbacks that limited its applications in the long term, including relatively high material cost and brittleness. Silver nanowire (AgNW), as one of the alternative materials for ITO TCEs, has already gained much attention all over the world. In this paper, we reported a facile method to greatly enhance the transmittance of the AgNW TCEs without reducing the electrical conductivity based on moth-eye nanostructures, and the moth-eye nanostructures were fabricated by using a roll-to-roll ultraviolet nanoimprint lithography process. Besides, the effects of mechanical pressure and bending on the moth-eye nanostructure layer were also investigated. In the research, the optical transmittance of the flexible AgNW TCEs was enhanced from 81.3% to 86.0% by attaching moth-eye nanostructures onto the other side of the flexible polyethylene terephthalate substrate while the electrical conductivity of the AgNW TCEs was not sacrificed. This research can provide a direction for the cost-effective fabrication of moth-eye nanostructures and the transmittance improvement of the flexible transparent electrodes.

  13. Remote control radioactive-waste removal system uses modulated laser transmitter

    Science.gov (United States)

    Burcher, E. E.; Kopia, L. P.; Rowland, C. W.; Sinclair, A. R.

    1971-01-01

    Laser remote control system consists of transmitter, auto tracker, and receiver. Transmitter and tracker, packaged together and bore sighted, constitute control station, receiver is slave station. Model has five command channels and optical link operating range of 110 m.

  14. LOT-G3: Plasma Lamp, Ozonator and CW transmitter

    CERN Document Server

    Gobato, Ricardo; Gobato, Alekssander

    2015-01-01

    The LOT-G3 is designed to be a versatile equipment that perform several simple experiments for use in helping the physics classes for high school. Easy construction, low cost, using easily accessible materials. Its construction involves simple practices and knowledge of electromagnetism. It has the function of a plasma globe to demonstrate the ionization of a low pressure gas, as well as the formation of magnetic field. Can be used as sanitizer closed environments such as automotive vehicles in ozonator function, demonstrating the ionization of oxygen in the atmosphere, producing ozone, essential to life on earth. And as a sparks transmitter, low power, low frequency modulated continuous wave in (CW), for signals in Morse code. Therefore the equipment here called LOT-G3, has three functions: a plasma lamp, ozonator and CW transmitter.

  15. Inductance effects in the high-power transmitter crowbar system

    Science.gov (United States)

    Daeges, J.; Bhanji, A.

    1987-01-01

    The effective protection of a klystron in a high-power transmitter requires the diversion of all stored energy in the protected circuit through an alternate low-impedance path, the crowbar, such that less than 1 joule of energy is dumped into the klystron during an internal arc. A scheme of adding a bypass inductor in the crowbar-protected circuit of the high-power transmitter was tested using computer simulations and actual measurements under a test load. Although this scheme has several benefits, including less power dissipation in the resistor, the tests show that the presence of inductance in the portion of the circuit to be protected severely hampers effective crowbar operation.

  16. Laser transmitter for space-based sodium lidar instrument

    Science.gov (United States)

    Yu, Anthony W.; Krainak, Michael A.; Janches, Diego; Konoplev, Oleg

    2016-05-01

    We are currently developing a laser transmitter to remotely measure Sodium (Na) by adapting existing lidar technology with space flight heritage. The developed instrumentation will serve as the core for the planning of a Heliophysics mission targeted to study the composition and dynamics of Earth's mesosphere based on a spaceborne lidar that will measure the mesospheric Na layer. We present performance results from our laser transmitter development effort with emphasis on wavelength tuning and power scaling of a diode-pumped Q-switched self-Raman c-cut Nd:YVO4 laser with intra-cavity frequency doubling that could produce multi-watt 589 nm wavelength output. We will review technologies that provide strong leverage for the sodium lidar laser system with strong heritage from past and current space flight missions.

  17. Exciter For X-Band Transmitter And Receiver

    Science.gov (United States)

    Johns, Carl E.

    1989-01-01

    Report describes developmental X-band exciter for X-band uplink subsystem of Deep Space Network. X-band transmitter-exciting signal expected to have fractional frequency stability of 5.2 X 10 to negative 15th power during 1,000-second integration period. Generates coherent test signals for S- and X-band Block III translator of Deep Space Network, Doppler-reference signal for associated Doppler-extractor system, first-local-oscillator signal for associated receiver, and reference signal for associated ranging subsystem. Tests of prototype exciter show controlling and monitoring and internal phase-correcting loops perform according to applicable design criteria. Measurements of stability of frequency and of single-sideband noise spectral density of transmitter-exciting signal made subsequently.

  18. Multiband RF circuits and techniques for wireless transmitters

    CERN Document Server

    Chen, Wenhua; Ghannouchi, Fadhel M

    2016-01-01

    This book introduces systematic design methods for passive and active RF circuits and techniques, including state-of-the-art digital enhancement techniques. As the very first book dedicated to multiband RF circuits and techniques, this work provides an overview of the evolution of transmitter architecture and discusses current digital predistortion techniques. Readers will find a collection of novel research ideas and new architectures in concurrent multiband power dividers, power amplifiers and related digital enhancement techniques. This book will be of great interest to academic researchers, R&D engineers, wireless transmitter and protocol designers, as well as graduate students who wish to learn the core architectures, principles and methods of multiband RF circuits and techniques. .

  19. Multiuser MIMO Transmitter Optimization for Inter-Cell Interference Mitigation

    CERN Document Server

    Huh, Hoon; Caire, Giuseppe

    2009-01-01

    The optimization of the transmitter precoder (steering vectors and power allocation) for a MIMO Broadcast Channel (MIMO-BC) subject to general linear constraints is considered. These include various types of system constraints such as sum power, per-antenna or per-group-of-antennas power constraints, and "forbidden interference direction" constraints. We consider the transmitter optimization problem under either the optimal dirty-paper coding and the simple suboptimal linear zero-forcing beamforming strategies. In both cases, we provide numerically efficient algorithms that solve the problem in the most general form. As an application, we consider a multi-cell scenario with partial cell cooperation, where each cell optimizes its precoder by taking into account interference constraints on specific users in adjacent cells. The effectiveness of the proposed method is evaluated in a simple system setting with two adjacent cells, under different fairness criteria that emphasize the role of users near the cell "bou...

  20. Morphology and transmittance of porous alumina on glass substrate

    Energy Technology Data Exchange (ETDEWEB)

    Guo Peitao, E-mail: guopeitao@hotmail.com [Wuhan University of Technology. Wuhan (China); Xia Zhilin [Wuhan University of Technology. Wuhan (China); Key Laboratory of Low Dimensional Materials and Application Technology, Xiangtan University, Ministry of Education, Xiangtan (China); Xue Yiyu [Wuhan University of Technology. Wuhan (China); Huang Caihua [China Three Gorges University, Yichang (China); Zhao Lixin [Wuhan University of Technology. Wuhan (China)

    2011-02-01

    The porous optical film has higher threshold of laser-induced damage than densified films, for the study of mechanism of laser-induced damage of porous optical film with ordered pore structure. Porous anodic alumina (PAA) film with high transmittance on glass substrate has been prepared. Aluminum film was deposited on glass substrate by means of resistance and electron beam heat (EBH) evaporation. Porous alumina was prepared in oxalic acid solution under different anodizing conditions. At normal incidence, the optical transmittance spectrum over 300-1000 nm spectra region was obtained by spectrophotometer. SEM was introduced to analysis the morphology of the porous alumina film. The pore aperture increased with the increase of anodizing voltage, which resulted in a rapid decrease of the pore concentration and the optical thickness of porous alumina film. Damage morphology of porous alumina film is found to be typically defects initiated, and the defect is the pore presented on the film.

  1. Transmittance spectroscopy and transmitted multispectral imaging to map covered paints

    Directory of Open Access Journals (Sweden)

    Antonino Cosentino

    2016-01-01

    Full Text Available Transmitted spectroscopy and transmitted multispectral imaging in the 400-900 nm range have been applied for the mapping and tentative identification of paints covered by a white preparation as in the case of a ground laid for reusing a canvas for another painting. These methods can be applied to polychrome works of art, as long as their support and new preparation are sufficiently translucent. This work presents the transmittance spectra acquired from a test board consisting of a prepared canvas with swatches of 54 pigments covered with titanium white and the multispectral images realized with transmitted light to map covered paints on a mock-up painting. It was observed that 18 out of 54 historical pigments provide characteristic transmittance spectra even underneath a titanium white preparation layer and that transmitted light multispectral imaging can map hidden paint layers.

  2. Aerosol Optical Thickness Derived From Atmospheric Transmittance Using Spectroradiometer Measurements

    Science.gov (United States)

    Hwee San, Hslim; Matjafri, M. Z.; Abdullah, Abdul K.; Chow Jeng, C. J.

    section The objective of this study was to test the feasibility of hand held spectroradiometer measurements for the retrieval AOT values Twenty-six stations were chosen randomly around Penang Island and the atmospheric transmittance measurements were collected using a handheld spectroradiometer The corresponding PM10 concentrations were measured using a portable DustTrak Aerosol Monitor 8520 simultaneously with the measurements of the transmittance data The AOT values were calculated using the Beer-Lambert-Bouguer law Linear relationship was found between AOT and PM10 values in this study Finally a PM10 map was created using Kriging interpolation technique The result of the study showed the potential of a spectroradiometer data for the retrieval of AOT and PM10 to provide the air pollution information

  3. A passive transmitter for quantum key distribution with coherent light

    CERN Document Server

    Curty, Marcos; Pruneri, Valerio; Mitchell, Morgan W

    2011-01-01

    Signal state preparation in quantum key distribution schemes can be realized using either an active or a passive source. Passive sources might be valuable in some scenarios; for instance, in those experimental setups operating at high transmission rates, since no externally driven element is required. Typical passive transmitters involve parametric down-conversion. More recently, it has been shown that phase-randomized coherent pulses also allow passive generation of decoy states and Bennett-Brassard 1984 (BB84) polarization signals, though the combination of both setups in a single passive source is cumbersome. In this paper, we present a complete passive transmitter that prepares decoy-state BB84 signals using coherent light. Our method employs sum-frequency generation together with linear optical components and classical photodetectors. In the asymptotic limit of an infinite long experiment, the resulting secret key rate (per pulse) is comparable to the one delivered by an active decoy-state BB84 setup wit...

  4. New digital-input transmitter for missile telemetry

    Science.gov (United States)

    Rieger, J. L.; Woodworth, P. H.

    It is pointed out that telemetry for aircraft and missiles has been in use by the military and its suppliers since the 1950's, using a variety of frequencies and formats. However, the techniques used in airborne telemetry have changed as a consequence of advances in electronic technology. Use of digital pulse-code modulation instead of the analog time-sampled pulse-amptitude modulation (PAM) produced by an analog commutator has advantages in noise performance in instances where the telemetry link is performing near the threshold of noise. The present investigation is concerned with a digital-input transmitter which accepts binary format directly from a TTL source and has applicability in both standard telemetry and encrypted systems. Attention is given to telemetry modulation systems, data encryption requirements, the modulation interface, and transmitter characteristics.

  5. 46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Collateral deposit fund, letter of transmittal, Form MA-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY... Collateral deposit fund, letter of transmittal, Form MA-302. The standard form of letter of transmittal...

  6. 47 CFR 95.647 - FRS unit and R/C transmitter antennas.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false FRS unit and R/C transmitter antennas. 95.647... transmitter antennas. The antenna of each FRS unit, and the antenna of each R/C station transmitting in the 72-76 MHz band, must be an integral part of the transmitter. The antenna must have no gain (as...

  7. System for Isolation Testing of RF Transmitters and Receivers

    Science.gov (United States)

    2012-08-03

    one such software defined radio is the open source GNU radio platform utilizing the Universal Software Radio Peripheral. [0019] The advantages of...to a system that can perform isolation testing of a radio frequency (RF) transmitter or an RF receiver. (2) Description of the Prior Art [0004...Currently, the testing and diagnosing of a faulty radio frequency (RF) transmission and receiving systems requires that the system be taken out of the

  8. Laser Transmitters for the optical link systems used in CMS

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    In the CMS experiment of the now new flagship LHC optical links will be used for the tracker readout system. One part of this components will be semiconductor laser (~50.000 !!!), named correctly: 1310 nm InGaAsP (DCPBH-MQW) edge-emitting laser. They are foreseen as transmitter in the Tx Hybrid part of the optical link system.

  9. Secure Broadcasting with Imperfect Channel State Information at the Transmitter

    KAUST Repository

    Hyadi, Amal

    2015-11-13

    We investigate the problem of secure broadcasting over fast fading channels with imperfect main channel state information (CSI) at the transmitter. In particular, we analyze the effect of the noisy estimation of the main CSI on the throughput of a broadcast channel where the transmission is intended for multiple legitimate receivers in the presence of an eavesdropper. Besides, we consider the realistic case where the transmitter is only aware of the statistics of the eavesdropper’s CSI and not of its channel’s realizations. First, we discuss the common message transmission case where the source broadcasts the same information to all the receivers, and we provide an upper and a lower bounds on the ergodic secrecy capacity. For this case, we show that the secrecy rate is limited by the legitimate receiver having, on average, the worst main channel link and we prove that a non-zero secrecy rate can still be achieved even when the CSI at the transmitter is noisy. Then, we look at the independent messages case where the transmitter broadcasts multiple messages to the receivers, and each intended user is interested in an independent message. For this case, we present an expression for the achievable secrecy sum-rate and an upper bound on the secrecy sum-capacity and we show that, in the limit of large number of legitimate receivers K, our achievable secrecy sum-rate follows the scaling law log((1−) log(K)), where is the estimation error variance of the main CSI. The special cases of high SNR, perfect and no-main CSI are also analyzed. Analytical derivations and numerical results are presented to illustrate the obtained expressions for the case of independent and identically distributed Rayleigh fading channels.

  10. SLVS Transmitter and Receiver for CBM MUCH ASIC

    Science.gov (United States)

    Bulbakov, I.

    2017-01-01

    Scalable Low Voltage Signaling (SLVS) Transmitter (Tx) and Receiver (Rx) IP blocks are designed in the UMC 180 nm CMOS technology as component of the readout ASIC for the muon chambers (MUCH) of the Compressed Baryonic Matter (CBM) experiment at FAIR (Darmstadt, Germany). These blocks are a prototype of the physical layer of the e-link interface that is used for ASIC-GBTx connection. The experimental results at 320 Mbit/s are presented.

  11. Intraperitoneal implantation of life-long telemetry transmitters in otariids

    OpenAIRE

    Haulena Martin; Horning Markus; Tuomi Pamela A; Mellish Jo-Ann E

    2008-01-01

    Abstract Background Pinnipeds, including many endangered and declining species, are inaccessible and difficult to monitor for extended periods using externally attached telemetry devices that are shed during the annual molt. Archival satellite transmitters were implanted intraperitoneally into four rehabilitated California sea lions (Zalophus californianus) and 15 wild juvenile Steller sea lions (Eumetopias jubatus) to determine the viability of this surgical technique for the deployment of l...

  12. Models of ionospheric VLF absorption of powerful ground based transmitters

    Science.gov (United States)

    Cohen, M. B.; Lehtinen, N. G.; Inan, U. S.

    2012-12-01

    Ground based Very Low Frequency (VLF, 3-30 kHz) radio transmitters play a role in precipitation of energetic Van Allen electrons. Initial analyses of the contribution of VLF transmitters to radiation belt losses were based on early models of trans-ionospheric propagation known as the Helliwell absorption curves, but some recent studies have found that the model overestimates (by 20-100 dB) the VLF energy reaching the magnetosphere. It was subsequently suggested that conversion of wave energy into electrostatic modes may be responsible for the error. We utilize a newly available extensive record of VLF transmitter energy reaching the magnetosphere, taken from the DEMETER satellite, and perform a direct comparison with a sophisticated full wave model of trans-ionospheric propagation. Although the model does not include the effect of ionospheric irregularities, it correctly predicts the average total power injected into the magnetosphere within several dB. The results, particularly at nighttime, appear to be robust against the variability of the ionospheric electron density. We conclude that the global effect of irregularity scattering on whistler mode conversion to quasi-electrostatic may be no larger than 6 dB.

  13. Reliability analysis for new technology-based transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Brissaud, Florent, E-mail: florent.brissaud.2007@utt.f [Institut National de l' Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Universite de Technologie de Troyes (UTT), Institut Charles Delaunay (ICD) and STMR UMR CNRS 6279, 12 rue Marie Curie, BP 2060, 10010 Troyes cedex (France); Barros, Anne; Berenguer, Christophe [Universite de Technologie de Troyes (UTT), Institut Charles Delaunay (ICD) and STMR UMR CNRS 6279, 12 rue Marie Curie, BP 2060, 10010 Troyes cedex (France); Charpentier, Dominique [Institut National de l' Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France)

    2011-02-15

    The reliability analysis of new technology-based transmitters has to deal with specific issues: various interactions between both material elements and functions, undefined behaviours under faulty conditions, several transmitted data, and little reliability feedback. To handle these particularities, a '3-step' model is proposed, based on goal tree-success tree (GTST) approaches to represent both the functional and material aspects, and includes the faults and failures as a third part for supporting reliability analyses. The behavioural aspects are provided by relationship matrices, also denoted master logic diagrams (MLD), with stochastic values which represent direct relationships between system elements. Relationship analyses are then proposed to assess the effect of any fault or failure on any material element or function. Taking these relationships into account, the probabilities of malfunction and failure modes are evaluated according to time. Furthermore, uncertainty analyses tend to show that even if the input data and system behaviour are not well known, these previous results can be obtained in a relatively precise way. An illustration is provided by a case study on an infrared gas transmitter. These properties make the proposed model and corresponding reliability analyses especially suitable for intelligent transmitters (or 'smart sensors').

  14. Pathologic and physiologic effects associated with long-term intracoelomic transmitters in captive Siberian sturgeon

    Science.gov (United States)

    Boone, S. Shaun; Divers, Stephen J.; Camus, Alvin C.; Peterson, Douglas C.; Jennings, Cecil A.; Shelton, James L.; Hernandez, Sonia M.

    2015-01-01

    Intracoelomic transmitters are commonly used to evaluate migratory patterns, distribution, and habitat use of many species of fish. Currently, transmitter implantation relies mostly on the assumption that transmitters do not cause any adverse physiological or pathological effects on the animal. To investigate these effects, we surgically implanted 60 Siberian Sturgeon Acipenser baeri with transmitters that weighed less than 2% of their body weight. Postoperative assessments were conducted at 1, 2, 8, 12, 26, and 55 weeks to evaluate surgical healing and transmitter retention. Blood samples were collected before and after the 55-week study for serum cortisol analysis. Overall transmitter loss was 32%. Minor to moderate adhesions were noted at necropsy but did not appear to affect organ function. One fish was noted to have an intraintestinal transmitter at necropsy, but the fish was in overall good health. Long-term transmitter presence does not appear to increase serum cortisol levels or affect overall growth more than nontransmitter fish. Although long-term telemetry studies can be undertaken with minimal concern for negative physiological or pathological effects from transmitters, researchers should be aware that transmitter loss rates may be higher than previously thought. Mechanisms for transmitter loss may include expulsion through the surgical incision, expulsion through the mucocutaneous junction between the large intestine and the vent, or intraintestinal capture and expulsion through the vent. Received February 10, 2013; accepted June 10, 2013

  15. Effects of Sugars on the Light Transmittance of Tapioca Starch Pastes during Cold Storage

    Directory of Open Access Journals (Sweden)

    Xiaoyu Zhang

    2014-04-01

    Full Text Available The aim of this study is to study the influence of sugars (glucose, sucrose and trehalose on the light transmittance of Tapioca Starch (TS gels during cold storage. The effects of sugars on the light transmittance of TS gels were investigated at the concentration of starch 2% (w:w during cold storage. The results showed the light transmittance of TS gels could be improved by sugar addition, according to the sugar type and concentration. The light transmittance increased with the increase of the concentration of the same kind of sugar. And the improvement of light transmittance with the sugar type was according to the order: trehalose>sucrose>glucose. Whether addition of sugar or not, light transmittance decreased with the extension of storage days. Therefore, light transmittance experiment is a simple and inexpensive method to study the effects of sugars on the retrogradation of starch gels with low-concentration.

  16. Polarized reflectance and transmittance distribution functions of the ocean surface.

    Science.gov (United States)

    Hieronymi, Martin

    2016-07-11

    Two aspects of ocean modelling are treated: representation of ocean waves considering all size-classes of waves and tracing of light-interactions at the wavy sea surface. Nonlinear wave profiles are realized accounting for a wide range of climatologically relevant sea states and wind speeds. Polarized ray tracing is used to investigate air-incident and whitecap-free reflectance and transmittance distributions with high angular resolution subject to sea-characterizing parameters, such as significant wave height, peak wave period, wind speed, and surface roughness. Wave-shadowing effects of incident and multiple reflected rays are fully considered. Their influence mostly starts with incidence angles greater than 60°, i.e., when the sun is near the horizon, and is especially pronounced for steep sea states. The net effect of multiple reflections is a redistribution of reflectance and transmittance fractions in their respective hemispheres and a slight increase of the net transmission of light into the sea. Revised reflectance and transmittance distribution functions, RDF and TDF, are provided depending on surface roughness in terms of the mean-square slope; reference is made to other sea state parameters. In comparison with the slope statistics approach, uncertainties related to sun near the horizon are reduced and on average this study yields somewhat higher reflectance values with some variability related to the sea state. By means of provided data, irradiance and radiance reflectances can be computed using desired sky radiance distributions, e.g., clear sky, overcast or partly cloudy sky, as well as wind or sea state information including wave propagation direction.

  17. A spectral method for retrieving cloud optical thickness and effective radius from surface-based transmittance measurements

    Directory of Open Access Journals (Sweden)

    P. J. McBride

    2011-01-01

    Full Text Available We introduce a new multispectral method for the retrieval of optical thickness and effective radius from cloud transmittance, which is less sensitive to effective radius than cloud reflectance. Based on data from the moderate spectral resolution observations of the Solar Spectral Flux Radiometer (SSFR and Shortwave Spectroradiometer (SWS, we use the spectral shape of transmitted radiance as a means of retrieving effective radius from cloud transmittance. The observations were taken during the International Chemistry Experiment in the Arctic Lower Troposphere and at the Southern Great Plains (SGP site of the Atmospheric Radiation Measurement (ARM Climate Research Facility. The spectral shape was quantified by fitting a slope to the normalized transmittance between 1565 nm and 1634 nm. The retrieval was performed by comparing the observed slope at 1565 nm and the transmittance at 515 nm with a pre-calculated library (lookup table. An estimate of the retrieval uncertainty was provided by propagating the uncertainty of the observations through the best-fit algorithm. We compare the new retrieval with an algorithm that uses transmittance at two wavelengths, a method often used with cloud reflectance. The liquid water path (LWP is derived from the retrieved optical thickness and effective radius, assuming a cloud with effective radius varying linearly with altitude above cloud base, and compared to the retrieved liquid water path from a microwave radiometer. Retrievals from two MODIS overpasses of the SGP were also compared. The data taken from the SGP was under thicker cloud than the case used from ICEALOT, with average optical thickness of 44 and 22, respectively. For the time period with the thicker clouds, the dual-wavelength method and the slope method retrieved nearly indistinguishable results. The dual-wavelength method, however, resulted in slightly higher average relative effective radius uncertainty of 12.9 μm±12.8%, as compared to 12.8

  18. BOREAS RSS-1 PARABOLA SSA Surface Reflectance and Transmittance Data

    Science.gov (United States)

    Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Deering, Donald D.; Eck, Thomas F.; Banerjee, Babu

    2000-01-01

    The BOREAS RSS-1 team collected surface reflectance and transmittance data from three forested sites in the SSA. This data set contains averaged reflectance factors and transmitted radiances measured by the PARABOLA instrument at selected sites in the BOREAS SSA at different view angles and at three wavelength bands throughout the day. PARABOLA measurements were made during each of the three BOREAS IFCs during the growing season of 1994 at three SSA tower flux sites as well as during the FFC-T. Additional measurements were made in early and mid-1996 during the FFC-W and during IFC-2. The data are stored in tabular ASCII files.

  19. [GABA, a key transmitter for fetal brain maturation].

    Science.gov (United States)

    Ben-Ari, Yehezkel

    2007-01-01

    GABA, the principal inhibitory transmitter excites immature neurons in all animal species studied. This is due to the higher intracellular concentration of chloride at early developmental stages. Excitatory actions of GABA play an important action in brain maturation. Recent observations also suggest an abrupt shift during delivery that exerts a neuro-protective action contributing to reduce the sequels of trauma and anoxic episodes. These observations have important clinical implications in relation to delivery associated insults but also preterm delivery and more generally consumption of agents during gestation.

  20. Transmitter and Precoding Order Optimization for Nonlinear Downlink Beamforming

    CERN Document Server

    Michel, Thomas

    2007-01-01

    The downlink of a multiple-input multiple output (MIMO) broadcast channel (BC) is considered, where each receiver is equipped with a single antenna and the transmitter performs nonlinear Dirty-Paper Coding (DPC). We present an efficient algorithm that finds the optimum transmit filters and power allocation as well as the optimum precoding order(s) possibly affording time-sharing between individual DPC orders. Subsequently necessary and sufficient conditions for the optimality of an arbitrary precoding order are derived. Based on these we propose a suboptimal algorithm showing excellent performance and having low complexity.

  1. A Clock Fingerprints-Based Approach for Wireless Transmitter Identification

    Science.gov (United States)

    Zhao, Caidan; Xie, Liang; Huang, Lianfen; Yao, Yan

    Cognitive radio (CR) was proposed as one of the promising solutions for low spectrum utilization. However, security problems such as the primary user emulation (PUE) attack severely limit its applications. In this paper, we propose a clock fingerprints-based authentication approach to prevent PUE attacks in CR networks with the help of curve fitting and classifier. An experimental setup was constructed using the WLAN cards and software radio devices, and the corresponding results show that satisfied identification can be achieved for wireless transmitters.

  2. Simplified transmitter design for MIMO systems with channel uncertainty

    Institute of Scientific and Technical Information of China (English)

    DU Juan; KANG Gui-xia; ZHANG Ping

    2009-01-01

    This article investigates transmitter design in Rayleigh fading multiple input multiple output (MIMO) channels with spatial correlation when there are channel uncertainties caused by a combined effect of channel estimation error and limited feedback. To overcome the high computational complexity of the optimal transmit power allocation, a simple and suboptimal allocation is proposed by exploiting the transmission constraint and differentiating a bound based on Jensen inequality on the channel capacity. The simulation results show that the mutual information corresponding to the proposed power allocation closely approaches the channel capacity corresponding to the optimal one and meanwhile the computational complexity is greatly reduced.

  3. Behavioral modelling and predistortion of wideband wireless transmitters

    CERN Document Server

    Ghannouchi, Fadhel M; Helaoui, Mohamed

    2015-01-01

    Covers theoretical and practical aspects related to the behavioral modelling and predistortion of wireless transmitters and power amplifiers. It includes simulation software that enables the users to apply the theory presented in the book. In the first section, the reader is given the general background of nonlinear dynamic systems along with their behavioral modelling from all its aspects. In the second part, a comprehensive compilation of behavioral models formulations and structures is provided including memory polynomial based models, box oriented models such as Hammerstein-based and Wiene

  4. Considerations on Safety Evaluation of Safety grade Smart Transmitter in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Tae; Jeong, Choong heui [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-05-15

    Non-safety grade smart transmitters have been used for I and C systems of NPPs(Nuclear Power Plants). Smart transmitter is a microprocessor-based device including software and provides capability for digital signals to be communicated on top of the 4-20 mA analog signals. Recently, smart transmitters have been used for safety grade I and C systems as well as non-safety grade I and C system for SKN 3 and 4. Due to potential benefits of smart transmitter, it is anticipated smart transmitters will be widely used safety-related applications at NPPs. For those reasons, smart transmitter's technology and characteristics need to be investigated. Smart transmitters have been used for safety grade as well as non-safety grade I and C system since SKN 3 and 4. Due to potential benefits of smart transmitter, it is anticipated smart transmitters will be widely used safety-related applications at NPPs. For those reasons, smart transmitter's technology and characteristics need to be investigated. To get useful information about that, we surveyed EPRI qualification report, NRC event report, and SKN 3 and 4's review.

  5. Assessment of the calibration curve for transmittance pulse-oximetry

    Science.gov (United States)

    Doronin, A.; Fine, I.; Meglinski, I.

    2011-11-01

    Optical/laser modalities provide a broad variety of practical solutions for clinical diagnostics and therapy in a range from imaging of single cells and molecules to non-invasive biopsy of specific biological tissues and organs tomography. Near-infrared transmittance pulse oximetry with laser diodes is the accepted standard in current clinical practice and widely used for noninvasive monitoring of oxygen saturation in arterial blood hemoglobin. Conceptual design of practical pulse oximetry systems requires careful selection of various technical parameters, including intensity, wavelength, beam size and profile of incident laser radiation, size, numerical aperture of the detector, as well as a clear understanding of how the spatial and temporal structural alterations in biological tissues can be linked with and can be distinguished by variations of these parameters. In current letter utilizing state-of-the-art NVIDEA CUDA technology, a new object oriented programming paradigm and on-line solutions we introduce a computational tool applied for human finger transmittance spectra simulation and assessment of calibration curve for near-infrared transmitted pulseoximetry.

  6. Optimum Transmitter Power Control in WCDMA Cellular Systems

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Power control is an important technique in WCDMA mobile systems for both increasing system capacity and guaranteeing the required QoS (time delay and wireless link transmission quality) of multimedia services. The optimum power control for narrow band CDMA cellular systems is a problem of single threshold optimization. Because these systems have only one type of traffic and have the same QoS requirement. However, WCDMA mobile systems should provide multimedia services and different types of traffic have different QoS requirements. Thus, the power control in WCDMA mobile systems doesn't be a problem of single threshold optimizing, but turns into the optimizing problem of multi-thresholds. In this paper, we analyze the power control problem in WCDMA cellular mobile systems and propose the optimum transmitter power control algorithm. Three criteria to optimize transmitter power levels of multi-thresholds based on grading the priority orders of multimedia services are proposed. Simulation results show that the proposed algorithms are more effective than conventional algorithms and can provide better performance for WCDMA cellular mobile systems.

  7. Rapid light transmittance measurements in paper-based microfluidic devices

    Directory of Open Access Journals (Sweden)

    Christina Swanson

    2015-09-01

    Full Text Available We developed methodology and built a portable reader to assess light transmittance in paper-based microfluidic devices in a highly sensitive, user-friendly and field-appropriate manner. By sandwiching the paper assay between micro-light-emitting diodes and micro-photodetectors, the reader quantifies light transmittance through the paper independent of ambient light conditions. To demonstrate the utility of the reader, we created a single-use paper-based microfluidic assay for measurement of alanine aminotransferase, an indicator of liver health in blood. The paper assay and reader system accurately differentiated alanine aminotransferase levels across the human reference range and demonstrated significant differences at clinically relevant cutoff values. Results were provided within 10 min and were automatically generated without complex image analysis. Performance of this point-of-care diagnostic rivals the accuracy of lab-based spectrometer tests at a fraction of the cost, while matching the timeliness of low-cost portable assays, which have historically shown lower accuracy. This combination of features allows flexible deployment of low cost and quantitative diagnostics to resource-poor settings.

  8. Mammography Facilities

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Mammography Facility Database is updated periodically based on information received from the four FDA-approved accreditation bodies: the American College of...

  9. Health Facilities

    Science.gov (United States)

    Health facilities are places that provide health care. They include hospitals, clinics, outpatient care centers, and specialized care centers, such as birthing centers and psychiatric care centers. When you ...

  10. Canyon Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — B Plant, T Plant, U Plant, PUREX, and REDOX (see their links) are the five facilities at Hanford where the original objective was plutonium removal from the uranium...

  11. Design of a fiber-optic transmitter for microwave analog transmission with high phase stability

    Science.gov (United States)

    Logan, R. T., Jr.; Lutes, G. F.; Primas, L. E.; Maleki, L.

    1990-01-01

    The principal considerations in the design of fiber-optic transmitters for highly phase-stable radio frequency and microwave analog transmission are discussed. Criteria for a fiber-optic transmitter design with improved amplitude and phase-noise performance are developed through consideration of factors affecting the phase noise, including low-frequency laser-bias supply noise, the magnitude and proximity of external reflections into the laser, and temperature excursions of the laser-transmitter package.

  12. Probing the intracellular calcium sensitivity of transmitter release during synaptic facilitation

    OpenAIRE

    Felmy, F.; Neher, E.; Schneggenburger, R

    2003-01-01

    In nerve terminals, residual Ca2+ remaining from previous activity can cause facilitation of transmitter release by a mechanism that is still under debate. Here we show that the intracellular Ca2+ sensitivity of transmitter release at the calyx of Held is largely unchanged during facilitation, which leaves an increased microdomain Ca2+ signal as a possible mechanism for facilitation. We measured the Ca2+ dependencies of facilitation, as well as of transmitter release, to estimate the required...

  13. Modified method for external attachment of transmitters to birds using two subcutaneous anchors

    Science.gov (United States)

    Lewis, T.L.; Flint, P.L.

    2008-01-01

    Of the transmitter attachment techniques for birds, the subcutaneous anchor provides a secure attachment that yields relatively few secondary effects. However, the use of subcutaneous anchors has been limited by transmitter size and retention time. Using a modified method of attachment that utilized two subcutaneous anchors, we deployed 69 GPS transmitters, plus 13 VHF transmitters that were similar in size and weight to GPS models, on Pacific Black Brant (Branta bernicla nigricans). Prior to our study, only harnesses were used for attaching GPS transmitters on birds, mainly because GPS transmitters are too large for other external attachment techniques and implantation in the body cavity attenuates the GPS signal. Thus, to increase the size capacity of anchor attachment and to avoid the well-documented negative effects of harnesses on behavior and survival, we added a second anchor at the transmitter's posterior end. The double-anchor attachment technique was quickly and easily accomplished in the field, requiring bird handling times of killed by hunters (3-6 mo after deployment) retained their GPS transmitters. For studies involving the use of relatively large transmitters, the double-anchor method appears to provide a viable alternative for external attachment. ?? 2008 Association of Field Ornithologists.

  14. All polymer chip for amperometric studies of transmitter release from large groups of neuronal cells

    DEFF Research Database (Denmark)

    Larsen, Simon T.; Taboryski, Rafael

    2012-01-01

    We present an all polymer electrochemical chip for simple detection of transmitter release from large groups of cultured PC 12 cells. Conductive polymer PEDOT:tosylate microelectrodes were used together with constant potential amperometry to obtain easy-to-analyze oxidation signals from potassium......-induced release of transmitter molecules. The nature of the resulting current peaks is discussed, and the time for restoring transmitter reservoirs is studied. The relationship between released transmitters and potassium concentration was found to fit to a sigmoidal dose–response curve. Finally, we demonstrate...

  15. Study of relationship between structure and transmittance of diamond-like carbon (DLC) films

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this paper, the transparent hard diamond-like carbon (DLC) films were deposited on glass substrate by magnetic confined radio-frequency plasma chemical vapor deposition. The structure of films was studied by Raman spectra and X-ray photoelectron spectra (XPS), the transmittance of films by Spectrophotometer. The mechanism of the influence of films structure on transmittance of the films was discussed. The results show that the thickness of films was lower than 100nm, and the transmittance was over 90% in 380-780 nm region. Discussion in theory on the influence of film structure on transmittance was correspondence to experiment results.

  16. Comparison between ASHRAE and ISO thermal transmittance calculation methods

    DEFF Research Database (Denmark)

    Blanusa, Petar; Goss, William P.; Roth, Hartwig

    2007-01-01

    the Heat Transfer and Total Optical Properties of Fenestration Products, Public Review Draft of Standard 142P, American Society of Heating, Refrigerating and Air Conditioning Engineers, Atlanta, 1998]) and in Europe [ISO 10077-2. Thermal Performance of Windows, Doors and Shutters-Calculation of Thermal...... Transmittance-Part 2: Numerical Method for Frames, International Standards Organization, Geneva, 2003]. The two approaches, called the ASHRAE and ISO methods, are different in the way they treat the effect of the glazing spacer on the heat transfer through the frame and the glazing unit near the frame....... The ASHRAE method assumes that the spacer effects both the heat transfer through the frame and the heat transfer through the glazing in an "edge-of glass" region 63.5mm (2.5in.) from the glazing/frame sight line. The ISO method assumes that the additional heat transfer due to the existence of the spacer...

  17. The 20 GHz spacecraft FET solid state transmitter

    Science.gov (United States)

    1983-01-01

    The engineering development of a solid state transmitter amplifier operating in the 20 GHz frequency band using GaAs field effect transistors (FETs) was detailed. The major efforts include GaAs FET device development, single-ended amplifier stage, balanced amplifier stage, cascaded stage and radial combiner designs, and amplifier integration and test. A multistage GaAs FET amplifier capable of 8.2 W CW output over the 17.9 to 19.1 GHz frequency band was developed. The GaAs FET devices developed represent state of the art FET power device technology. Further device improvements are necessary to increase the bandwidth to 2.5 GHz, improve dc-to-RF efficiency, and increase power capability at the device level. Higher power devices will simplify the amplifier combining scheme, reducing the size and weight of the overall amplifier.

  18. Leaf Relative Water Content Estimated from Leaf Reflectance and Transmittance

    Science.gov (United States)

    Vanderbilt, Vern; Daughtry, Craig; Dahlgren, Robert

    2016-01-01

    Remotely sensing the water status of plants and the water content of canopies remain long term goals of remote sensing research. In the research we report here, we used optical polarization techniques to monitor the light reflected from the leaf interior, R, as well as the leaf transmittance, T, as the relative water content (RWC) of corn (Zea mays) leaves decreased. Our results show that R and T both change nonlinearly. The result show that the nonlinearities cancel in the ratio R/T, which appears linearly related to RWC for RWC less than 90%. The results suggest that potentially leaf water status and perhaps even canopy water status could be monitored starting from leaf and canopy optical measurements.

  19. Electromagnetic Cavity Effects from Transmitters Inside a Launch Vehicle Fairing

    Science.gov (United States)

    Trout, Dawn H.; Wahid, Parveen F.; Stanley, James E.

    2009-01-01

    This paper provides insight into the difficult analytical issue for launch vehicles and spacecraft that has applicability outside of the launch industry. Radiation from spacecraft or launch vehicle antennas located within enclosures in the launch vehicle generates an electromagnetic environment that is difficult to accurately predict. This paper discusses the test results of power levels produced by a transmitter within a representative scaled vehicle fairing model and provides preliminary modeling results at the low end of the frequency test range using a commercial tool. Initially, the walls of the fairing are aluminum and later, layered with materials to simulate acoustic blanketing structures that are typical in payload fairings. The effects of these blanketing materials on the power levels within the fairing are examined.

  20. Comparison between ASHRAE and ISO thermal transmittance calculation methods

    DEFF Research Database (Denmark)

    Blanusa, Petar; Goss, William P.; Roth, Hartwig

    2007-01-01

    the Heat Transfer and Total Optical Properties of Fenestration Products, Public Review Draft of Standard 142P, American Society of Heating, Refrigerating and Air Conditioning Engineers, Atlanta, 1998]) and in Europe [ISO 10077-2. Thermal Performance of Windows, Doors and Shutters-Calculation of Thermal...... Transmittance-Part 2: Numerical Method for Frames, International Standards Organization, Geneva, 2003]. The two approaches, called the ASHRAE and ISO methods, are different in the way they treat the effect of the glazing spacer on the heat transfer through the frame and the glazing unit near the frame....... The ASHRAE method assumes that the spacer effects both the heat transfer through the frame and the heat transfer through the glazing in an "edge-of glass" region 63.5mm (2.5in.) from the glazing/frame sight line. The ISO method assumes that the additional heat transfer due to the existence of the spacer...

  1. Public Safety Transmitter Towers, Public Safety Transmitter Towers, Published in 2008, 1:24000 (1in=2000ft) scale, Lafayette County Land Records.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Public Safety Transmitter Towers dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Survey/GPS information as of 2008. It...

  2. Finishing and Commissioning the New Arecibo HF Facility

    Science.gov (United States)

    Sulzer, M. P.; Gonzalez, S. A.

    2011-12-01

    The imminent completion of the major tasks in the construction of the New Arecibo HF facility means that we must verify that the components are working as intended. The antenna system and the transmitters must be separately commissioned before they can be connected together so that we an be sure it will provide 83 dbW at 8.175 MHz, and 80 dbW at 5.1 MHz. The antenna system will be ready for initial testing in September. It Illuminates the 305 meter dish using dipoles near the surface of the dish transmitting upward to a wire mesh sub-reflector. There are three crossed dipoles for each of the two frequencies. The dipoles are supported on towers mounted on concrete pads underneath the dish. Each dipole element is connected to a transmitter through a three inch coax line. The tower foundations are nearly complete, and the towers will be erected in early September, and we expect to have at least one crossed dipole in place for initial testing by the end of September. We will need to make some measurements on the antenna system to ensure that it meets our requirements. One requirement is to match the antenna impedance to the transmission line and the transmitter closely enough to meet the transmitter specifications, the closer, the better. We have additional requirements; for example, it is necessary for efficient use of the facility that the polarization be close to circular. In most experiments, we want O mode excitation. If we were to transmit linear only half the power would reach the reflection height. The symmetry of the system assures that most of the conditions for achieving accurate circular polarization are met, but one condition is not: that exciting the transmitters driving the orthogonal elements at 90 degrees assures 90 degree separation in the corresponding antenna currents. One of the dipoles of each pair points toward the center of the array. If we think of the three crossed dipoles as consisting of a reference and two that are excited relative to it

  3. Asian Facilities

    Science.gov (United States)

    Nakahata, M.

    2011-04-01

    Asian underground facilities are reviewed. The YangYang underground Laboratory in Korea and the Kamioka observatory in Japan are operational and several astrophysical experiments are running. Indian Neutrino Observatory(INO) and China JinPing Underground Laboratory (CJPL) are under construction and underground experiments are being prepared. Current activities and future prospects at those underground sites are described.

  4. The Efficacy of Ultraviolet Radiation for Sterilizing Tools Used for Surgically Implanting Transmitters into Fish

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Ricardo W.; Markillie, Lye Meng; Colotelo, Alison HA; Gay, Marybeth E.; Woodley, Christa M.; Brown, Richard S.

    2013-02-28

    Telemetry is frequently used to examine the behavior of fish, and the transmitters used are normally surgically implanted into the coelom of fish. Implantation requires the use of surgical tools such as scalpels, forceps, needle holders, and sutures. When several fish are implanted consecutively for large telemetry studies, it is common for surgical tools to be sterilized or, at minimum, disinfected between each use so that pathogens that may be present are not spread among fish. However, autoclaving tools can take a long period of time, and chemical sterilants or disinfectants can be harmful to both humans and fish and have varied effectiveness. Ultraviolet (UV) radiation is commonly used to disinfect water in aquaculture facilities. However, this technology has not been widely used to sterilize tools for surgical implantation of transmitters in fish. To determine its efficacy for this application, Pacific Northwest National Laboratory researchers used UV radiation to disinfect surgical tools (i.e., forceps, needle holder, stab scalpel, and suture) that were exposed to one of four aquatic organisms that typically lead to negative health issues for salmonids. These organisms included Aeromonas salmonicida, Flavobacterium psychrophilum, Renibacterium salmoninarum, and Saprolegnia parasitica. Surgical tools were exposed to the bacteria by dipping them into a confluent suspension of three varying concentrations (i.e., low, medium, high). After exposure to the bacterial culture, tools were placed into a mobile Millipore UV sterilization apparatus. The tools were then exposed for three different time periods—2, 5, or 15 min. S. parasitica, a water mold, was tested using an agar plate method and forceps-pinch method. UV light exposures of 5 and 15 min were effective at killing all four organisms. UV light was also effective at killing Geobacillus stearothermophilus, the organism used as a biological indicator to verify effectiveness of steam sterilizers. These

  5. On-Line Hyperspectral Transmittance Imaging for Internal Defect Detection of Pickling Cucumbers

    Science.gov (United States)

    Hyperspectral imaging technique under transmittance mode was investigated for detection of internal defect in pickling cucumbers such as carpel suture separation or hollow cucumbers caused by mechanical stress. A prototype of on-line hyperspectral transmittance imaging system was developed for real...

  6. Effect of package light transmittance on vitamin content of milk. Part 2: UHT whole milk

    NARCIS (Netherlands)

    Saffert, A.; Pieper, G.; Jetten, J.

    2008-01-01

    This work is the second part of a milk study evaluating the effect of package light transmittance on the vitamin content of milk, in this case on UHT whole milk. The milk was stored at three different light intensities in polyethylene terephthalate (PET) bottles with varying light transmittance as

  7. A 100–800 MHz 8-Path polyphase transmitter with mixer duty-cycle control achieving

    NARCIS (Netherlands)

    Subhan, Saqib; Klumperink, Eric; Ghaffari, Amir; Wienk, Gerard; Nauta, Bram

    2014-01-01

    Radio transceivers capable of dynamic spectrum access require frequency agile transmitters with a clean output spectrum. High-Q filters are difficult to implement on chip and have limited tuning range. Transmitters with high linearity and broadband harmonic rejection can be more flexible and require

  8. Negative control in two-component signal transduction by transmitter phosphatase activity.

    Science.gov (United States)

    Huynh, TuAnh Ngoc; Stewart, Valley

    2011-10-01

    Bifunctional sensor transmitter modules of two-component systems exert both positive and negative control on the receiver domain of the cognate response regulator. In negative control, the transmitter module accelerates the rate of phospho-receiver dephosphorylation. This transmitter phosphatase reaction serves the important physiological functions of resetting response regulator phosphorylation level and suppressing cross-talk. Although the biochemical reactions underlying positive control are reasonably well understood, the mechanism for transmitter phosphatase activity has been unknown. A recent hypothesis is that the transmitter phosphatase reaction is catalysed by a conserved Gln, Asn or Thr residue, via a hydrogen bond between the amide or hydroxyl group and the nucleophilic water molecule in acyl-phosphate hydrolysis. This hypothetical mechanism closely resembles the established mechanisms of auxiliary phosphatases such as CheZ and CheX, and may be widely conserved in two-component signal transduction. In addition to the proposed catalytic residues, transmitter phosphatase activity also requires the correct transmitter conformation and appropriate interactions with the receiver. Evidence suggests that the phosphatase-competent and autokinase-competent states are mutually exclusive, and the corresponding negative and positive activities are likely to be reciprocally regulated through dynamic control of transmitter conformations. © 2011 Blackwell Publishing Ltd.

  9. Effect of package light transmittance on vitamin content of milk. Part 2: UHT whole milk

    NARCIS (Netherlands)

    Saffert, A.; Pieper, G.; Jetten, J.

    2008-01-01

    This work is the second part of a milk study evaluating the effect of package light transmittance on the vitamin content of milk, in this case on UHT whole milk. The milk was stored at three different light intensities in polyethylene terephthalate (PET) bottles with varying light transmittance as d

  10. Subcutaneous implantation of satellite transmitters with percutaneous antennae into male polar bears (Ursus maritimus)

    Science.gov (United States)

    Mulcahy, D.M.; Garner, G.

    1999-01-01

    Male polar bears (Ursus maritimus) have not been successfully instrumented with satellite transmitters because they readily shed collar-mounted transmitters. Seven male polar bears were captured on the pack ice off the northern coast of Alaska and surgically implanted with satellite transmitters with percutaneous antennae into the subcutaneous space of the dorsal cervical region. Transmitters failed prematurely with lifetimes of 30-161 days (x?? = 97 days). Efforts to relocate implanted bears after transmitters failed were not successful. The mean number of location solutions per transmitter was 204 (range 118-369). An average of 10% and 19% of the locations were accurate to < 150 m and to 150-350 m, respectively. Our successful tracking of male polar bears, the high quality of locations obtained from transmitters with percutaneous antennae implanted in the subcutaneous space, and the low visibility of such units make further technical development worthwhile if the reason for premature failure of the transmitters can be determined. Copyright 1999 by American Association of Zoo Veterinarians.

  11. Integrated S-band transmitter with on-chip DC-DC converter and control loop

    NARCIS (Netherlands)

    Brouzes, H.; Geurts, S.; Besselink, M.; Telli, A.; Hek, A.P. de; Bent, G. van der; Vliet, F.E. van

    2012-01-01

    A highly integrated high-power transmitter has been designed in a high breakdown GaAs MMIC technology. The transmitter includes, on top of an S-Band 10 W class-F HPA, a DC/DC converter and its associated gate driver, the full voltage regulation control loop, which provides a significant step for pha

  12. Effects of implanted radio transmitters with percutaneous antennas on the behavior of Canada Geese

    Science.gov (United States)

    Hupp, J.W.; Ruhl, G.A.; Pearce, J.M.; Mulcahy, D.M.; Tomeo, M.A.

    2003-01-01

    We examined whether surgically-implanted radio transmitters with percutaneous antennas affected behavior of Lesser Canada Geese (Branta canadensis parvipes) in Anchorage, Alaska. We implanted either a 26-g VHF radio transmitter or a larger VHF radio that was the same mass (35 g) and shape as a satellite transmitter in the coelom of adult females captured during molt in 2000. A control group of females was marked with leg bands. We simultaneously observed behavior of radio-marked and control females from 4-62 d following capture. We observed no differences in the proportion of time birds in different treatments allocated among grazing, resting, comfort, walking, and alert behavior. Females in different treatments spent a similar proportion of time in the water. Implantation of radio transmitters did not affect the frequency of agonistic interactions. We conclude that coelomic radio transmitters with percutaneous antennas had minimal effects on the behavior of Canada Geese.

  13. 2-Micron Laser Transmitter for Coherent CO2 DIAL Measurement

    Science.gov (United States)

    Singh, Upendra N.; Bai, Yingxin; Yu, Jirong

    2009-01-01

    Carbon dioxide (CO2) has been recognized as one of the most important greenhouse gases. It is essential for the study of global warming to accurately measure the CO2 concentration in the atmosphere and continuously record its variation. A high repetition rate, highly efficient, Q-switched 2-micron laser system as the transmitter of a coherent differential absorption lidar for CO2 measurement has been developed in NASA Langley Research Center. This laser system is capable of making a vertical profiling of CO2 from ground and column measurement of CO2 from air and space-borne platform. The transmitter is a master-slave laser system. The master laser operates in a single frequency, either on-line or off-line of a selected CO2 absorption line. The slave laser is a Q-switched ring-cavity Ho:YLF laser which is pumped by a Tm:fiber laser. The repetition rate can be adjusted from a few hundred Hz to 10 kHz. The injection seeding success rate is from 99.4% to 99.95%. For 1 kHz operation, the output pulse energy is 5.5mJ with the pulse length of 50 ns. The optical-to-optical efficiency is 39% when the pump power is 14.5W. A Ho:YLF laser operating in the range of 2.05 micrometers can be tuned over several characteristic lines of CO2 absorption. Experimentally, a diode pumped Ho:Tm:YLF laser has been successfully used as the transmitter of coherent differential absorption lidar for the measurement of CO2 with a repetition rate of 5 Hz and pulse energy of 75 mJ. For coherent detection, high repetition rate is required for speckle averaging to obtain highly precise measurements. However, a diode pumped Ho:Tm:YLF laser can not operate in high repetition rate due to the large heat loading and up-conversion. A Tm:fiber laser pumped Ho:YLF laser with low heat loading can operate in high repetition rate. A theoretical model has been established to simulate the performance of Tm:fiber laser pumped Ho:YLF lasers. For continuous wave (CW) operation, high pump intensity with small beam

  14. Solar active envelope module with an adjustable transmittance/absorptance

    Directory of Open Access Journals (Sweden)

    C. Villasante Villasante

    2015-06-01

    Full Text Available A solar active envelope module with a high flexibility degree is proposed in this paper. The transparent module controls the day-lighting of the room, improving the indoor environment, while absorbing the superfluous solar energy inside. That energy is used to increase the efficiency of heating, ventilation, and the air-conditioning (HVAC system of the building. This is carried out through a fine control of the absorptance of the envelope module. The active envelope module consists of three glazed chambers with advanced coatings and frames to assure a minimum thermal transmittance while allowing transparency. A fluid containing heat-absorbing nanoparticles flows inside the central chamber and is heated up due to the impinging solar energy. Unlike other systems proposed in the past, which included transparency control systems based on complex filters and chemical processes, the absorption of the module is controlled by the variation of the thickness of the central chamber with a mechanical device. That is, varying the thickness of the central chamber, it allows controlling the absorptance of the whole system and, as a result, indoor day-lighting and thermal loads. Therefore, a new system is proposed that enables to:  

  15. Computational Investigations of THz Transmittance in the Atmosphere

    Science.gov (United States)

    Yang, Xingyu; Calhoun, Casey; Calhoun, Ronald

    2016-06-01

    With the recent scientific advancements in Terahertz (THz) wave propagation and reception technology, there has been significant development in new possibilities for using THz waves - offering new possibilities in THz detection and ranging. A first foundational step toward this goal is to better understand THz transmittance in the turbulent atmosphere. In this project, a frequency modulation pattern of THz waves was created by utilizing a system of shifting frequency based on temperature, air humidity, and distance of transmission. The total path loss of the wave in air, based on the wave spread and molecular absorption, was then modeled using radiative transfer theory, onto a set of JavaHAWK filtered-HITRAN data representative of an air sample. This data was used to generate a path loss matrix, which was then used to optimize frequency of transmission for the specific conditions. The concept to be evaluated is whether adaptive frequency modulated THz might usefully decrease transmission losses by adjusting to atmospheric conditions (such as local variations in temperature and humidity).

  16. Gas detection by using transmittance estimation and segmentation approaches

    Science.gov (United States)

    Özısık Baskurt, Didem; Gür, Yusuf; Ömrüuzun, Fatih; ćetin, Yasemin Yardımcı

    2016-10-01

    Hyperspectral imaging for gas detection applications is an under-researched topic. The same gas model is used in most of the gas detection studies in the literature. This model aims to formulate the scene covering the gas emission as well as the background and the atmosphere. Therefore, the model requires prior knowledge on transmittance, emissivity, and temperature values of the components in the scene. The commonly used approaches to estimate these parameters include atmospheric modeling and statistical inference. However, accessing such information is costly in remote detection applications. Some studies avoid background characterization by decomposing the scene using spectral-spatial information. There are several studies in the literature using this model. They aim to detect various types of gases on different parts of electromagnetic spectrum. Most of these studies use hyperspectral radiance information regarding the scene. However, using brightness temperature map of the data instead of radiance data is more suitable for direct analysis. For this reason, we used brightness temperature spectrum in this study. On the other hand, the detection algorithms are generally based on pixel based investigation. Since the emission of the gas is sourced by a pipe or a chimney, investigating the emission region at the segment level increases detection accuracy. In this study, we used an iterative spectral feature based pixel clustering algorithm followed by spatial segmentation.

  17. When a pressure transmitter leaves the linearity: The Rosemount case

    Energy Technology Data Exchange (ETDEWEB)

    Blazquez, J. [Department of Nuclear Fission, CIEMAT, 22 Complutense Av., 28040 Madrid (Spain)]. E-mail: juan.blazquez@ciemat.es

    2006-07-01

    When a Rosemount pressure transmitter experiences the inner silicone oil-loss syndrome, it loses its linear behaviour. In such a case, the response time is not unique; as a consequence, focusing the sensor surveillance to the response time, as required by the technical specifications of the nuclear plant, might have no sense. In which way is the sensor dynamic not linear? Answering this open question is the main objective of this work. A bilinear model can explain most of the features of the noise signal. A more elaborated model is built in order to explain the results of the deterministic experiments. The corresponding non-linear differential equation is solved exactly for the step response, and an approximate expression is found for the anomalous response time. When the driving term of the dynamic is not a step, the differential equation is solved approximately using the Picard iteration procedure. It gives some light on why the oscillations lose symmetry or why the amplitude probability of the noise signal shows skewness. (author)

  18. Designing Parallel Bus Using Universal Asynchronous Receiver Transmitter

    Directory of Open Access Journals (Sweden)

    Satyandra Sharad

    2013-04-01

    Full Text Available This paper entitled “DESIGNING PARALLEL BUSUSING UNIVERSAL ASYNCHRONOUS RECEIVER TRANSMITTER” is designed to the core of a UART interface module, which includes both receive and transmit modules, and the command parser. This paper will be a viable solution to design parallel buses with the help of UART. In the test bench , there is a RFM(register file model to which we write/read back data from just to check our design .The txt file issues serial inputs to the core and the core outputs parallel data and address in the form of bus. This bus is connected to our RFM (register file model instantiated in the test bench along with the design. This makes easy to retrieve parallel data from serial input. The base of the paper is to use microcontroller along with other components to interface with the physical world. In contrast, most serial communication must first be converted back into parallel form by a universal asynchronous receiver/transmitter (UART before they may be directly connected to a data bus. Both Transmissions (Parallel and Serial are used to connect peripheral devices and enable us to communicate with these devices. The UART core described here is designed using VHDL and implemented on Xilinx Vertex FPGA.

  19. Wavelength-agile integrated optical transmitters for analog applications

    Science.gov (United States)

    Johansson, Leif A.; Chen, Chin-Hui; Akulova, Yuliya A.; Fish, Gregory A.; Coldren, Larry A.

    2003-12-01

    A summary of current work involving the development of high performance, wavelength-tunable integrated optical transmitters for analog applications is given. The performance of sampled-grating DBR lasers integrated with an SOA and an electroabsorption or Mach-Zehnder modulator is evaluated in terms of E/O conversion efficiency, noise performance and dynamic range. Optimization options to maximize either gain, noise figure or spurious-free dynamic range in analog link applications are discussed. It is shown how the combination of chip-scale integration and the use of bulk waveguide Franz-Keldysh absorption allows coupling of a large optical power level into the electroabsorption modulator, and its effects on the modulation response and analog link performance. Link results on an integrated SGDBR-SOA-EAM device includes a sub-octave SFDR in the 125 to 127 dB/Hz4/5 range and a broadband SFDR of 103-107 dB/Hz2/3 limited by third order intermodulation products or 95-98 dB/Hz1/2, limited by second order intermodulation products, over a 1528 to 1573 nm wavelength range.

  20. DESIGN AND DEVELOPMENT OF XBAND OSCILLATOR FOR FM TELEMETRY TRANSMITTER

    Directory of Open Access Journals (Sweden)

    S.SREEKANTH,

    2011-05-01

    Full Text Available Oscillator represents the basic microwave energy source for all microwave systems such as radar, communication and navigation. A typical oscillator essentially consist of an active device and passivefrequency determining resonant element such as dielectric resonator, micro strip resonator and tuned circuit for fixed frequency oscillators, varactor for tunable oscillators. The transistor used was fujitsu, FHX13LG, operating at DC bias of 2V and 25mA.The oscillator was designed using the 1/3 oscillation rule because of its effectiveness and simplicity. Oscillator feedback was connected to HEMT in a common source configuration using transmission line and capacitor. The emphasis has been on high power, low noise, small cost, high reliability and high temperature stability.Practical design aspects including the choice of transistor, negative feedback circuits, load coupling, low phase noise, quality factor and operation at the highest phase slope for minimum phase noise areincluded. This paper deals Design and Development of X band Oscillator for Telemetry Transmitter by using ADS simulation software and it has been designed at 8 GHz frequency.

  1. Computational Investigations of THz Transmittance in the Atmosphere

    Directory of Open Access Journals (Sweden)

    Yang Xingyu

    2016-01-01

    Full Text Available With the recent scientific advancements in Terahertz (THz wave propagation and reception technology, there has been significant development in new possibilities for using THz waves – offering new possibilities in THz detection and ranging. A first foundational step toward this goal is to better understand THz transmittance in the turbulent atmosphere. In this project, a frequency modulation pattern of THz waves was created by utilizing a system of shifting frequency based on temperature, air humidity, and distance of transmission. The total path loss of the wave in air, based on the wave spread and molecular absorption, was then modeled using radiative transfer theory, onto a set of JavaHAWK filtered-HITRAN data representative of an air sample. This data was used to generate a path loss matrix, which was then used to optimize frequency of transmission for the specific conditions. The concept to be evaluated is whether adaptive frequency modulated THz might usefully decrease transmission losses by adjusting to atmospheric conditions (such as local variations in temperature and humidity.

  2. Emission Facilities - Erosion & Sediment Control Facilities

    Data.gov (United States)

    NSGIC Education | GIS Inventory — An Erosion and Sediment Control Facility is a DEP primary facility type related to the Water Pollution Control program. The following sub-facility types related to...

  3. On the Optimality of Opportunistic Interference Alignment in 3-Transmitter MIMO Interference Channels

    CERN Document Server

    Lee, Jung Hoon; Love, David J

    2011-01-01

    In this paper, we propose opportunistic interference alignment (OIA) for three-transmitter multiple-input multiple-output (MIMO) interference channels (ICs). In the proposed OIA scheme, each transmitter has its own user group that consists of $K$ users, and each transmitter opportunistically selects the user whose received interference signals are most aligned. Thus, three-transmitter MIMO IC is opportunistically constructed by three transmitters and their selected users. Contrary to conventional IA, perfect channel information for all of the interference links is not required at the transmitter. Each user just needs to feed back one scalar value in the proposed OIA scheme. When the number of receive antennas is $N_R$ (with $N_R=2M$) and the number of transmit antennas is $N_T$ (with $N_T\\ge M$), we prove that each transmitter can achieve $M$ degrees of freedom (DoF) as the number of users in each group goes to infinity ($K\\to\\infty$), in comparison with the $\\frac{2M}{3}$ DoF known to be achievable in the th...

  4. A New CO2 Transmittance Parameterization and Its Impact on the GLA GCM

    Science.gov (United States)

    Wobus, R.; Wui, M. L. C.; Susskind, J.

    1985-01-01

    The Wu-Kaplan radiation parameterization (Krishnamurthy, 1982) used in the GLA Global Circulation Model (GCM) was improved by replacing its fixed tables of CO2 transmittance in the 15 micron band with models developed by regression on line-by-line transmittances. The transmittances between layers are modeled as products of effective sublayer transmittances. The GLA GCM was integrated for 20 days starting at OZ, January 21, 1979, using the transmittance model. In the control run the fixed table of 15 micron CO2 transmittances is used. The effect of the change of initial cooling rate is illustrated by a map of the difference of 50 mb temperature after 6 hours. The cooling is reduced over high topography, where the fixed table underestimates the transmittance, and is reduced slightly throughout the tropics and the north polar area where the stratosphere is relatively cold. Over elevated topography the surface cooling increases, also as expected. The stratospheric temperature increases over a degree in the arctic and smaller amounts over Antarctica and elsewhere. Tropospheric equilibrium temperature response is obscured by time dependent differences in synoptic disturbances.

  5. Radio transmitter implants in the horns of both the white and the black rhinoceros in the Kruger National Park

    Directory of Open Access Journals (Sweden)

    D.J. Pienaar

    1991-09-01

    Full Text Available The procedure for implanting radio transmitters into the horns of white and black rhinoceroses is described. Mean transmitter life in the white rhinoceros was 13,9 months which is significantly longer than the 9,7 months in black rhinoceros. In the white rhinoceros a significant sex-related difference in transmitter life was found with the transmitters in males lasting a mean of 12,1 months compared to the 15,3 months in females.

  6. The timing of phasic transmitter release is Ca2+-dependent and lacks a direct influence of presynaptic membrane potential

    OpenAIRE

    Felmy, Felix; Neher, Erwin; Schneggenburger, Ralf

    2003-01-01

    Ca2+ influx through voltage-gated Ca2+ channels and the resulting elevation of intracellular Ca2+ concentration, [Ca2+]i, triggers transmitter release in nerve terminals. However, it is controversial whether in addition to the opening of Ca2+ channels, membrane potential directly affects transmitter release. Here, we assayed the influence of membrane potential on transmitter release at the calyx of Held nerve terminals. Transmitter release was evoked by presynaptic Ca2+ uncaging, or by presyn...

  7. 47 CFR 95.419 - (CB Rule 19) May I operate my CB station transmitter by remote control?

    Science.gov (United States)

    2010-10-01

    ... transmitter by remote control? 95.419 Section 95.419 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Operate A Cb Station § 95.419 (CB Rule 19) May I operate my CB station transmitter by remote control? (a) You may not operate a CB station transmitter by radio remote control. (b) You may operate a CB...

  8. 77 FR 41473 - Proposed Technical Standard Order (TSO)-C126b, 406 MHz Emergency Locator Transmitters (ELT) and...

    Science.gov (United States)

    2012-07-13

    ... ELT mounting. Advisory material discouraging the use of hook and loop fasteners includes the following... Transmitters (ELT) and Notice of Intent To Withdraw TSO Authorizations (TSOA) for TSO-C91a, Emergency Locator Transmitter (ELT) Equipment, and TSO-C126/C126a, 406 MHz Emergency Locator Transmitters (ELT) AGENCY:...

  9. The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier

    Energy Technology Data Exchange (ETDEWEB)

    J.G. Kulpin, K.J. Kleman, R.A. Legg

    2012-07-01

    A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

  10. Eight-wavelength distributed-Bragg-reflector (DBR) laser array transmitter for WDM applications

    Science.gov (United States)

    Fallahi, Mahmoud; McGreer, K. A.; Delage, Andre; Neophytou, A.; Templeton, Ian M.; Champion, Garth; Chatenoud, F.; Barber, Richard A.; Wang, Weijian; He, Jian Jun; Koteles, Emil S.

    1995-03-01

    We report on the design, growth, fabrication and characterization of monolithic wavelength division multiplexed (WDM) laser array transmitter and receiver chips produced by the Canadian Solid State Optoelectronics Consortium. The transmitter chip includes multiple, discrete wavelength, distributed Bragg reflector (DBR) laser diodes monolithically integrated with waveguide combiners fabricated using an InGaAs/GaAs heterostructure. The corresponding wavelength demultiplexer unit is based on a Rowland circle grating spectrometer monolithically integrated with a metal-semiconductor-metal (MSM) detector array fabricated on an InGaAs/AlGaAs/GaAs heterostructure. The epitaxial layer wafers for both transmitter and receiver modules were grown in single molecular beam epitaxy (MBE) runs.

  11. The Design of New-Type Smart Temperature Transmitter Based on Computer Networks

    Institute of Scientific and Technical Information of China (English)

    LING Zhen-bao; WANG Jun; QIU Chun-ling

    2004-01-01

    In this article, the functions and features of another generation of single-chip microcomputer MSP430 with low power consumption and high performance are introduced. Based on these,the method of designing the intelligent and miniaturized temperature transmitter is proposed. The design block diagram and software flowchart of circuit hardware of every part of the intelligent temperature transmitter are supplied. This transmitter has advantages like high cost-performance ratio, small size, strong noise resistance-good interchangeability, broad field of application,and it can also be used for measuring and transmitting the temperature in the control system.

  12. In-Flight Performance of the Mercury Laser Altimeter Laser Transmitter

    Science.gov (United States)

    Yu, Anthony W.; Sun, Xiaoli; Li, Steven X.; Cavanaugh, John F.; Neumann, Gregory A.

    2014-01-01

    The Mercury Laser Altimeter (MLA) is one of the payload instruments on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, which was launched on August 3, 2004. MLA maps Mercury's shape and topographic landforms and other surface characteristics using a diode-pumped solid-state laser transmitter and a silicon avalanche photodiode receiver that measures the round-trip time of individual laser pulses. The laser transmitter has been operating nominally during planetary flyby measurements and in orbit about Mercury since March 2011. In this paper, we review the MLA laser transmitter telemetry data and evaluate the performance of solid-state lasers under extended operation in a space environment.

  13. Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters

    DEFF Research Database (Denmark)

    Skovrind, Mikkel; Christensen, Emil A.F.; Carl, Henrik

    2013-01-01

    a strong proof of concept of oviduct-inserted acoustic transmitters in brackish and marine fish spawning studies. The transmitter expulsions were validated using an egg map, which was based on visual observations of perch egg-strands, and 11 of the 12 expulsed transmitters (92%) were located in areas...... with eggs. Many fish spawned in the brackish water with salinities up to 9.6 PSU. These salinities are higher than those previously observed for European perch spawning in the wild, and call for further investigations of salinity tolerance in perch eggs...

  14. Determination of Aluminium Content in Aluminium Hydroxide Formulation by FT-NIR Transmittance Spectroscopy

    DEFF Research Database (Denmark)

    Lai, Xuxin; Zheng, Yiwu; Søndergaard, Ib

    2007-01-01

    A method for determining the aluminium content of an aluminium hydroxide suspension using near infrared (NIR) transmittance spectroscopy has been developed. Inductively coupled plasma-atomic emission spectroscopy (ICP-AES) was used as reference method. The factors influencing the NIR analysis......-AES and NIR transmittance spectroscopy exhibit comparable precision and accuracy. The NIR method provides several advantages: no complicated sample preparation; easy to operate; fast and non-destructive. In conclusion, NIR transmittance spectroscopy can be an alternative analytical method for determining...

  15. Emergency Locator Transmitter System Performance During Three Full-Scale General Aviation Crash Tests

    Science.gov (United States)

    Littell, Justin D.; Stimson, Chad M.

    2016-01-01

    Full-scale crash tests were conducted on three Cessna 172 aircraft at NASA Langley Research Center's Landing and Impact Research facility during the summer of 2015. The purpose of the three tests was to evaluate the performance of commercially available Emergency Locator Transmitter (ELT) systems and support development of enhanced installation guidance. ELTs are used to provide location information to Search and Rescue (SAR) organizations in the event of an aviation distress situation, such as a crash. The crash tests simulated three differing severe but survivable crash conditions, in which it is expected that the onboard occupants have a reasonable chance of surviving the accident and would require assistance from SAR personnel. The first simulated an emergency landing onto a rigid surface, while the second and third simulated controlled flight into terrain. Multiple ELT systems were installed on each airplane according to federal regulations. The majority of the ELT systems performed nominally. In the systems which did not activate, post-test disassembly and inspection offered guidance for non-activation cause in some cases, while in others, no specific cause could be found. In a subset of installations purposely disregarding best practice guidelines, failure of the ELT-to-antenna cabling connections were found. Recommendations for enhanced installation guidance of ELT systems will be made to the Radio Technical Commission for Aeronautics (RTCA) Special Committee 229 for consideration for adoption in a future release of ELT minimum operational performance specifications. These recommendations will be based on the data gathered during this test series as well as a larger series of crash simulations using computer models that will be calibrated based on these data

  16. Air Quality Facilities

    Data.gov (United States)

    Iowa State University GIS Support and Research FacilityFacilities with operating permits for Title V of the Federal Clean Air Act, as well as facilities required to submit an air emissions inventory, and other facilities...

  17. Theme: Laboratory Facilities Improvement.

    Science.gov (United States)

    Miller, Glen M.; And Others

    1993-01-01

    Includes "Laboratory Facilities Improvement" (Miller); "Remodeling Laboratories for Agriscience Instruction" (Newman, Johnson); "Planning for Change" (Mulcahy); "Laboratory Facilities Improvement for Technology Transfer" (Harper); "Facilities for Agriscience Instruction" (Agnew et al.); "Laboratory Facility Improvement" (Boren, Dwyer); and…

  18. Solid State Transmitters for Water Vapor and Ozone DIAL Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We have developed a common architecture for laser transmitters that address requirements for water vapor as well as ground and airborne ozone lidar systems. Our...

  19. An unobtrusive liquid sensor utilizing a micromilled RF spark gap transmitter and resonant cavity

    Science.gov (United States)

    Berry, H.; Wilson, C.

    2009-09-01

    This paper reports on a new dielectric liquid sensor that utilizes an RF sparkgap transmitter coupled with an aluminum microwave resonant cavity. The transmitter is a micromilled polymer transmitter housing with patterned copper electrodes that generate micro-arcs. This transmitter which operates outside the measured liquid generates a directed ultrawideband signal which is received by the aluminum waveguide. Absorption resonances in the microwave cavity, measured with a spectrum analyzer are a function of the liquids' dielectric constant at lower frequencies, as well as from molecular vibrations/rotations at higher frequencies. In many chemical manufacturing processes, liquids being manufactured are removed, tested in a lab, and then disposed of, or else they will contaminate the full batch. In beer brewing, for instance, samples are removed, density tested for alcohol content, then disposed of. Using this sensor, the chemical process could be continuously monitored by a computerized system without risk of contamination.

  20. A CMOS UWB transmitter with Vivaldi Array for Ultra-fast Beam steering microwave radar

    National Research Council Canada - National Science Library

    De Oliveira, Alexandre M; Ascama, Héctor D. O; Hiramatsu, Roberto K; Kofuji, Sérgio T; Perotoni, Marcelo B; Justo, João F

    2013-01-01

    This work presents a new Ultra Wide Band (UWB) beamforming fifth-order derivative Gaussian pulse transmitter with dual small Vivaldi antennas for remote acquisition of vital signals in impulse radar applications...

  1. Compact self-contained electrical-to-optical converter/transmitter

    Energy Technology Data Exchange (ETDEWEB)

    Seligmann, D.A.; Moss, W.C.; Valk, T.C.; Conder, A.D.

    1992-12-31

    An electrical-to-optical converter/transmitter is disclosed. A first optical receiver and a second optical receiver are provided for receiving a calibrate command and a power switching signal, respectively, from a remote processor. A third receiver is provided for receiving an analog electrical signal from a transducer. A calibrator generates a reference signal in response to the calibrate command. A combiner mixes the electrical signal with the reference signal to form a calibrated signal. A converter converts the calibrated signal to an optical signal. A transmitter transmits the optical signal to the remote processor. A primary battery supplies power to the calibrator, the combiner, the converter, and the transmitter. An optically-activated switch supplies power to the calibrator, the combiner, the converter, and the transmitter in response to the power switching signal. An auxiliary battery supplies power continuously to the switch means.

  2. Two-flux transfer matrix model for predicting the reflectance and transmittance of duplex halftone prints.

    Science.gov (United States)

    Mazauric, Serge; Hébert, Mathieu; Simonot, Lionel; Fournel, Thierry

    2014-12-01

    We introduce a model allowing convenient calculation of the spectral reflectance and transmittance of duplex prints. It is based on flux transfer matrices and enables retrieving classical Kubelka-Munk formulas, as well as extended formulas for nonsymmetric layers. By making different assumptions on the flux transfers, we obtain two predictive models for the duplex halftone prints: the "duplex Clapper-Yule model," which is an extension of the classical Clapper-Yule model, and the "duplex primary reflectance-transmittance model." The two models can be calibrated from either reflectance or transmittance measurements; only the second model can be calibrated from both measurements, thus giving optimal accuracy for both reflectance and transmittance predictions. The conceptual differences between the two models are deeply analyzed, as well as their advantages and drawbacks in terms of calibration. According to the test carried out in this study with paper printed in inkjet, their predictive performances are good provided appropriate calibration options are selected.

  3. Conductive Polymer Microelectrodes for on-chip measurement of transmitter release from living cells

    DEFF Research Database (Denmark)

    Larsen, Simon Tylsgaard; Matteucci, Marco; Taboryski, Rafael J.

    2012-01-01

    driven cell trapping inside closed chip devices. Conductive polymer microelectrodes were used to measure transmitter release using electrochemical methods such as cyclic voltammetry and constant potential amperometry. By measuring the oxidation current at a cyclic voltammogram, the concentration...

  4. Television Transmitter Locations, Published in 2006, 1:1200 (1in=100ft) scale, Farmer.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Television Transmitter Locations dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Field Survey/GPS information as of 2006. Data...

  5. Flexible High Energy Lidar Transmitter for Remote Gas and Wind Sensing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Fibertek proposes a high energy and flexible operation 1570 nm pulsed lidar transmitter for airborne and space-based remote CO2 gas and doppler wind sensing. The...

  6. Use of a novel acoustic dissolved oxygen transmitter for fish telemetry

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Aarestrup, Kim; Steffensen, J.F.

    2006-01-01

    The multiple responses of fishes to changes in dissolved oxygen saturations have been studied widely in the laboratory. In contrast only few studies have included field observations. The objective of the present study was to evaluate the performance of a novel acoustic dissolved oxygen transmitter...... for field biotelemetry. The results demonstrated that the output of the transmitter was unaffected by three different temperatures (10 to 30 degrees C) and described the dissolved oxygen saturation with high accuracy (r(2) > 0.99) over the entire range of 0 to 191% saturation. The response time (>= 90......% of end value) of the transmitter was 12 s both in terms of decreasing (100 to 0%) and increasing (0 to 100%) oxygen saturations. When externally attached to fishes the present findings support the use of the transmitter for reliable dissolved oxygen measurements on individuals living in environments...

  7. Standard Practice for Calculation of Photometric Transmittance and Reflectance of Materials to Solar Radiation

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1988-01-01

    1.1 This practice describes the calculation of luminous (photometric) transmittance and reflectance of materials from spectral radiant transmittance and reflectance data obtained from Test Method E 903. 1.2 Determination of luminous transmittance by this practice is preferred over measurement of photometric transmittance by methods using the sun as a source and a photometer as detector except for transmitting sheet materials that are inhomogeneous, patterned, or corrugated. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  8. Space-Qualifiable 1064 nm Fiber Based Transmitter for Long Range Optical Communications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Fibertek has developed transmitters for Lidar and 3D imaging applications based on fiber optics architectures both at 1064nm. We have demonstrated an all fiber...

  9. Optical calculations and in-situ measurement of transmittance spectra of contaminant thin films

    Science.gov (United States)

    Shimazaki, Kazunori; Miyazaki, Eiji; Kimoto, Yugo

    2016-09-01

    Molecular contaminants outgassed from organic materials used for the spacecraft degrade the performance of optical surfaces of spacecraft. The influence of contaminants outgassed from epoxy resin on the spectral transmittance of the quartz substrate was investigated with an in-situ measurement system. The system can deposit the contaminants on temperature-controlled quartz substrates and the transmittance spectra were measured immediately after deposition in vacuum ambient. We tried to obtain the optical constants of the contaminant using transmittance spectrum and simple optical models for optical calculations. The optical constants were described with a harmonic oscillator model and the effective medium approximation model. This paper reports the in-situ measurement results of transmittance spectra of the epoxy-resin-induced contaminants. In addition, the result of optical calculations using the obtained optical constants were compared to the measurement results.

  10. Transmittance, Reflectance, and Emission Spectroscopy of Meteorites from the UV to the IR Spectral Range

    Science.gov (United States)

    Maturilli, A.; Helbert, J.; Koulen, J. M.; Ferrari, S.; Martellato, E.

    2016-08-01

    Transmittance, reflectance, and emissivity Spectra of six meteorites have been collected at the Planetary Spectroscopy Laboratory (PSL) of DLR in Berlin in the whole spectral range from the UV to the IR.

  11. High-efficiency resonantly pumped 1550-nm fiber-based laser transmitter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — nLight proposes the development of high efficiency, high average power 1550-nm laser transmitter system that is based on Er-doped fiber amplifier resonantly pumped...

  12. Effect of dust on the transmittance of low density polyethylene glazing in a tropical climate

    Energy Technology Data Exchange (ETDEWEB)

    Mastekbayeva, G.A.; Kumar, S. [Asian Inst. of Technology, Energy Program, Pathumthani (Thailand)

    2000-07-01

    The performance of solar systems (thermal or photovoltaic) is influenced by the ability of the glazing to transmit solar radiation to the collection surface, besides other factors, such as, incident radiation, tilt of collector, properties of materials, operating strategy, surroundings, etc. This paper discusses the influence of dust on the transmittance of a 0.2-mm-thick low-density polyethylene (LDPE) glazing used commonly in solar air heaters. The reduction in transmittance due to various dust deposition densities of Bangkok clay (size 53-75 {mu}m) has been measured and a correlation relating the dust deposition density and the transmittance given. Experimental observations of natural dust accumulation on an inclined (15deg) LDPE glazing at a tropical climatic condition during a 30-day period indicates a dust accumulation of 3.72 g/m{sup 2} and is found to reduce the global transmittance of the glazing from about 87.9% to 75.8%. (Author)

  13. Compact, Rugged and Low-Cost Atmospheric Ozone DIAL Transmitter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Bridger Photonics Inc. (Bridger) proposes to develop the most compact, efficient and low-cost ultra-violet ozone differential absorption lidar (DIAL) transmitter...

  14. Spectral reflectance and transmittance of stacks of nonscattering films printed with halftone colors

    OpenAIRE

    Hébert, Mathieu; Machizaud, Jacques

    2012-01-01

    International audience; This paper combines and extends two optical models based on a two-collimated-flux approach that we previously proposed for the reflectance and transmittance of nonscattering elements, i.e., stacked nonscattering plastic films on the one hand, and films printed in halftone on the other hand. Those two models are revisited and combined by introducing different reflectances and transmittances on the two sides of a printed film, a common situation in practice. We then addr...

  15. Comparison of Practical Implementation Limitations for Different Electronic Pre-Distortion Transmitter Structures

    DEFF Research Database (Denmark)

    Peucheret, Christophe; Tokle, Torger; Jeppesen, Palle;

    2006-01-01

    We examine different transmitter structures in electronic pre-distortion optical communication systems, and show that practical requirements due to electrical bandwidth limitation and driving signals amplitude and delay mismatches have a significant impact on system performance.......We examine different transmitter structures in electronic pre-distortion optical communication systems, and show that practical requirements due to electrical bandwidth limitation and driving signals amplitude and delay mismatches have a significant impact on system performance....

  16. Variable conductance heat pipe technology for precise temperature control of the NASA/DDLT transmitter

    Science.gov (United States)

    Vanevenhoven, D. E.; Antoniak, D.

    1989-01-01

    The application of variable conductance heat pipe technology for achieving precise temperature control to + or - 0.1 C for a space-based laser diode transmitter is described. Heat pipe theory of operation and test data are presented along with a discussion of its applicability for NASA's Direct Detection Laser Transceiver (DDLT) program. This design for the DDLT transmitter features a reduction in space radiator size and up to 42 percent reduction in prime power requirements.

  17. Heat treatment effect on erosion behavior of poly(methylmethacrylate) for optical transmittance efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Çoban, Onur, E-mail: onur_coban@yahoo.com

    2014-10-30

    Highlights: • Heat treatment improved both T{sub g} and microhardness values of PMMA. • FTIR results explained the hardness improvement with crosslinking phenomenon. • Both pristine and heat treated PMMA samples were showed ductile erosion behavior. • Maximum and minimum optical transmittance was observed at 15° and 90°, respectively. • Heat treatment improved optical transmittance under solid particle erosion. • Fresnel lenses should be heat treated at 85 °C for better optical transmittance. - Abstract: Influence of heat treatment on optical transmittance of poly(methyl methacrylate) (PMMA) samples was investigated under solid particle erosion. Heat treatment was employed at 85 °C for 1, 2 and 3 h. Effect of heat treatment on physical, chemical, mechanical and thermal properties of PMMA samples was investigated by differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, Vickers microhardness measurement methods. After these analysis, both pristine and heat treated PMMA samples were eroded at 15°, 30°, 45°, 60°, 75° and 90° impingement angles. Then, optical transmittance of all eroded PMMA samples was inspected by a UV–Vis spectrometer. Scanning electron microscopy (SEM) was used to explain the erosion mechanisms and to compare the roughness and optical transmittance of eroded PMMA surfaces. Heat treatment under glass transition temperature of PMMA increased the T{sub g} and hardness values. According to erosion test results, both pristine and heat treated PMMA samples were showed ductile erosion behavior. However; maximum and minimum optical transmittance values of eroded pristine PMMA samples were obtained for the angles of 15° and 90°, respectively. A positive effect of heat treatment on optical transmittance of PMMA was obtained for all impingement angles, but most pronounced effect was seen for 15°.

  18. Widely Linear Blind Adaptive Equalization for Transmitter IQ-Imbalance/Skew Compensation in Multicarrier Systems

    DEFF Research Database (Denmark)

    Porto da Silva, Edson; Zibar, Darko

    2016-01-01

    Simple analytical widely linear complex-valued models for IQ-imbalance and IQ-skew effects in multicarrier transmitters are presented. To compensate for such effects, a 4×4 MIMO widely linear adaptive equalizer is proposed and experimentally validated.......Simple analytical widely linear complex-valued models for IQ-imbalance and IQ-skew effects in multicarrier transmitters are presented. To compensate for such effects, a 4×4 MIMO widely linear adaptive equalizer is proposed and experimentally validated....

  19. The additional possibilities afforded by the method of partial reflections using high-power transmitters

    Science.gov (United States)

    Martynenko, S. I.; Chernogor, L. F.

    1984-04-01

    The objective of the study was to evaluate the possibility of obtaining additional information on the parameters of the lower ionosphere by using the method of partial reflections implemented with high-power transmitters. It is shown that measurements of the characteristics of partially reflected signals for various levels of the transmitter power provide information on the electron temperature perturbations and on several other parameters of the lower ionosphere. Analytical results are in good agreement with experimental data.

  20. Perancangan Prototipe Transmitter Beacon Black Box Locator Acoustic 37.5 kHz Pingers

    Directory of Open Access Journals (Sweden)

    RUSTAMAJI RUSTAMAJI

    2016-08-01

    Full Text Available ABSTRAK Pingers transmitter berfungsi untuk memancarkan sinyal atau getaran pulsa akustik pada black box. Frekuensi sinyal yang dipancarkan sebesar 37,5 kHz yang dimodulasikan oleh pulsa dengan durasi 10 ms setiap interval 1 second. Modulasi yang digunakan adalah modulasi on off keying. Dalam penelitian ini dibuat perancangan pingers transmitter yang tersusun atas rangkaian osilator, timer, inverter, switch dan rangkaian amplifier. Frekuensi 37,5 kHz tersebut dibangkitkan oleh rangkaian osilator colpitts, sedangkan lebar pulsa dengan durasi 10 ms dan pengulangan pulsa setiap interval 1 second dibangkitkan oleh rangkaian timer. Berdasarkan perancangan yang telah dibuat, output sinyal yang dihasilkan oleh prototipe pingers transmitter tersebut sebesar 37,69 kHz dengan lebar pulsa 9,8 ms setiap interval 1 second. Kata kunci: Black box, pingers transmitter, on off keying.   ABSTRACT Pingers transmitter is used to emits a signal or pulse of acoustic vibrations  in black box. The frequency of the transmitted signal is 37.5 kHz which is modulated by pulses with a duration of 10 ms every interval 1 second. The modulation that used this research is on off keying modulation. In this research, made the design of pingers transmitter which arrange of the oscillator circuit,timer, inverter, switch, and amplifier circuit. The 37.5 kHz frequency is generated by the colpitts oscillator circuit, while the pulse width with a duration of 10 ms,and each pulse repetition interval of 1 second generated by timer circuit. Based on the design that have made, signal output from the pingers transmitter prototype is 37.69 kHz, with the pulse width 9.8 ms every 1 second interval. Keywords : Black box, pingers transmitter, on off keying.

  1. Research on measurement method of optical transmittance of the artificial fog

    Science.gov (United States)

    Hu, Jianghua; Jian, Chaochao; Cui, Guangzhen; Lv, Xuliang; Rong, Xianhui

    2016-10-01

    The attenuation of light was a common result that the light was absorbed and scattered by the artificial fog particles when it transmitted in the artificial fog. The absorbing attenuation process of light transmission in the artificial fog was that the artificial fog converting incident light energy into other forms of internal energy (such as heat energy). The scattering attenuation process of light transmission in the artificial fog was that the artificial fog particles intercepting incident radiation energy to form infrasonic waves and to radiate peripherally so that the incident light energy was reduced on the original direction of transmission. The mechanism of light transmission attenuation in the artificial fog was analyzed. The formation method of the artificial fog was expounded and the measuring principle of the artificial fog transmittance was described. A simple and reliable measurement method of the optical transmittance of the artificial fog in the fog chamber was proposed. The optical transmittance measurement system of the artificial fog was built by using incandescent lamp, power with steady current and voltage, lens, selenium photocell, micro-galvanometer, optical bench, hygrothermograph, humidifier, etc. Under different conditions of humidity, the optical transmittance of the artificial fog was obtained on the basis of measuring the photocurrent before the fog was formed in the fog chamber. The test results show that the measurement system is stable and reliable. During the 43 minutes after the artificial fog was formed, the optical transmittance of the artificial fog was averagely less than 5 percent and the optical transmittance increased gradually with the extension of time. In addition, the optical transmittance of artificial fog didn't produce obvious change while air humidity increased from 68.7% to 85%. The measurement system can be used to measure transmittance of smoke screen, water mist and other aerosol.

  2. 50 Mb/s, 220-mW Laser-Array Transmitter

    Science.gov (United States)

    Cornwell, Donald M., Jr.

    1992-01-01

    Laser transmitter based on injection locking produces single-wavelength, diffraction-limited, single-lobe beam. Output stage is array of laser diodes producing non-diffraction-limited, multi-mode beam in absence of injection locking. Suitable for both free-space and optical-fiber communication systems. Because beam from transmitter focused to spot as small as 5 micrometers, devices usable for reading and writing optical disks at increased information densities. Application also in remote sensing and ranging.

  3. ELF/VLF Perturbations Above the Haarp Transmitter Recorded by the Demeter Satellite in the Upper Ionosphere

    Science.gov (United States)

    Titova, E. E.; Demekhov, A. G.; Mochalov, A. A.; Gvozdevsky, B. B.; Mogilevsky, M. M.; Parrot, M.

    2015-08-01

    In the studies of the data received from DEMETER (orbit altitude above the Earth is about 700 km), we detected for the first time electromagnetic perturbations, which are due to the ionospheric modification by HAARP, a high-power high-frequency transmitter, simultaneously in the extremely low-frequency (ELF, below 1200 Hz) and very low-frequency (VLF, below 20 kHz) ranges. Of the thirteen analyzed flybys of the satellite above the heated area, the ELF/VLF signals were detected in three cases in the daytime (LT = 11-12 h), when the minimum distance between the geomagnetic projections of the satellite and the heated area center on the Earth's surface did not exceed 31 km. During the nighttime flybys, the ELF/VLF perturbations were not detected. The size of the perturbed region was about 100 km. The amplitude, spectrum, and polarization of the ELF perturbations were analyzed, and their comparison with the characteristics of natural ELF noise above the HAARP transmitter was performed. In particular, it was shown that in the daytime the ELF perturbation amplitude above the heated area can exceed by a factor of 3 to 8 the amplitude of natural ELF noise. The absence of the nighttime records of artificial ELF/VLF perturbations above the heated area can be due to both the lower frequency of the heating signal, at which the heating occurs in the lower ionosphere, and the higher level of natural noise. The spectrum of the VLF signals related to the HAARP transmitter operation had two peaks at frequencies of 8 to 10 kHz and 15 to 18 kHz, which are close to the first and second harmonics of the lower-hybrid resonance in the heated area. The effect of the whistler wave propagation near the lower-hybrid resonance region on the perturbation spectrum recorded in the upper ionosphere for these signals has been demonstrated. In particular, some of the spectrum features can be explained by assuming that the VLF signals propagate in quasiresonance, rather than quasilongitudinal, regime

  4. Effects of radio transmitters on the behavior of Red-headed Woodpeckers.

    Energy Technology Data Exchange (ETDEWEB)

    Vukovich, Mark; Kilgo, John, C.

    2009-05-01

    ABSTRACT. Previous studies have revealed that radio-transmitters may affect bird behaviors, including feeding rates, foraging behavior, vigilance, and preening behavior. In addition, depending on the method of attachment, transmitters can potentially affect the ability of cavity-nesting birds to use cavities. Our objective was to evaluate effects of transmitters on the behavior of and use of cavities byRed-headedWoodpeckers (Melanerpes erythrocephalus). Using backpack harnesses, we attached 2.1-g transmitter packages that averaged 3.1% of body weight (range = 2.5–3.6%) to Red-headed Woodpeckers. We observed both radio-tagged (N = 23) and nonradio-tagged (N = 28) woodpeckers and determined the percentage of time spent engaged in each of five behaviors: flight, foraging, perching, preening, and territorial behavior. We found no difference between the two groups in the percentage of time engaged in each behavior. In addition, we found that transmitters had no apparent effect on use of cavities for roosting by radio-tagged woodpeckers (N = 25).We conclude that backpack transmitters weighing less than 3.6% of body weight had no impact on either their behavior or their ability to use cavities.

  5. Prediction of transmittance spectra for transparent composite electrodes with ultra-thin metal layers

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zhao; Alford, T. L., E-mail: TA@asu.edu [School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, Arizona 85287 (United States); Khorasani, Arash Elhami [ON Semiconductor Corp., Phoenix, Arizona 85005 (United States); Theodore, N. D. [CHD-Fab, Freescale Semiconductor Inc., Tempe, Arizona 85224 (United States); Dhar, A. [Intel Corp., 2501 NW 229th Ave, Hillsboro, Oregon 97124 (United States)

    2015-11-28

    Recent interest in indium-free transparent composite-electrodes (TCEs) has motivated theoretical and experimental efforts to better understand and enhance their electrical and optical properties. Various tools have been developed to calculate the optical transmittance of multilayer thin-film structures based on the transfer-matrix method. However, the factors that affect the accuracy of these calculations have not been investigated very much. In this study, two sets of TCEs, TiO{sub 2}/Au/TiO{sub 2} and TiO{sub 2}/Ag/TiO{sub 2}, were fabricated to study the factors that affect the accuracy of transmittance predictions. We found that the predicted transmittance can deviate significantly from measured transmittance for TCEs that have ultra-thin plasmonic metal layers. The ultrathin metal layer in the TCE is typically discontinuous. When light interacts with the metallic islands in this discontinuous layer, localized surface plasmons are generated. This causes extra light absorption, which then leads to the actual transmittance being lower than the predicted transmittance.

  6. Effect of ambient humidity on light transmittance through skin phantoms during cryogen spray cooling

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-San-Juan C, Julio [Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612 (United States); Department of Optics, INAOE, AP 51 and 216, CP 72000 Puebla, Pue (Mexico); Choi, Bernard [Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612 (United States); Franco, Walfre [Department of Mechanical Engineering, University of California, Riverside, CA 92521 (United States); Nelson, J Stuart [Beckman Laser Institute and Medical Clinic, University of California, Irvine, CA 92612 (United States); Aguilar, Guillermo [Department of Mechanical Engineering, University of California, Riverside, CA 92521 (United States)

    2006-01-07

    Cryogen spray cooling (CSC) is a technique employed to reduce the risk of epidermal damage during dermatologic laser surgery. However, while CSC protects the epidermis from non-specific thermal damage, it might reduce the effective fluence reaching the target chromophore due to scattering of light by the spray droplets and subsequent water condensation/freezing on the skin surface. The objective of this work was to study the effect of ambient humidity ({omega}) on light transmittance during CSC. An integrating sphere was employed to measure the dynamics of light transmittance through a deformable agar phantom during CSC. The study included two representative CSC spurt patterns studied using four {omega}: 57, 40, 20 and 12%. Results show that during CSC, as {omega} increased, light transmittance decreased. For the highest humidity level (57%) studied, light transmittance reached a minimum of 55% approximately 30 ms after spurt termination. In a controlled environment with {omega} = 12%, light transmittance reached a minimum of 87% approximately 30 ms after spurt termination. The reduced light transmittance immediately after spurt termination was most likely because of scattering of light caused by condensation of water vapour due to aggressive cooling of ambient air in the wake of the cryogen spurt.

  7. The deep-tow marine controlled-source electromagnetic transmitter system for gas hydrate exploration

    Science.gov (United States)

    Wang, Meng; Deng, Ming; Wu, Zhongliang; Luo, Xianhu; Jing, Jianen; Chen, Kai

    2017-02-01

    The Marine Controlled-Source Electromagnetic (MCSEM) method has been recognized as an important and effective tool to detect electrically resistive structures, such as oil, gas, and gas hydrate. The MCSEM performance is strongly influenced by the transmitter system design. We have developed a deep-tow MCSEM transmitter system. In this paper, some new technical details will be present. A 10,000 m optical-electrical composite cable is used to support high power transmission and fast data transfer; a new clock unit is designed to keep the synchronization between transmitter and receivers, and mark the time stamp into the transmission current full waveform; a data link is established to monitor the real-time altitude of the tail unit; an online insulation measuring instrument is adopted to monitor current leakage from high voltage transformer; a neutrally buoyant dipole antenna of copper cable and flexible electrodes are created to transmit the large power current into seawater; a new design method for the transmitter, which is called "real-time control technology of hardware parallelism", is described to achieve inverting and recording high-power current waveform, controlling functions, and collecting auxiliary information. We use a gas hydrate exploration test to verify the performance of the transmitter system, focusing on more technical details, rather than applications. The test shows that the transmitter can be used for gas hydrate exploration as an effective source.

  8. North Slope, Alaska ESI: FACILITY (Facility Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains data for oil field facilities for the North Slope of Alaska. Vector points in this data set represent oil field facility locations. This data...

  9. Jupiter Laser Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Jupiter Laser Facility is an institutional user facility in the Physical and Life Sciences Directorate at LLNL. The facility is designed to provide a high degree...

  10. Basic Research Firing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Basic Research Firing Facility is an indoor ballistic test facility that has recently transitioned from a customer-based facility to a dedicated basic research...

  11. Microwave reconstruction method using a circular antenna array cooperating with an internal transmitter

    Science.gov (United States)

    Zhou, Huiyuan; Narayanan, Ram M.; Balasingham, Ilangko

    2016-05-01

    This paper addresses the detection and imaging of a small tumor underneath the inner surface of the human intestine. The proposed system consists of an around-body antenna array cooperating with a capsule carrying a radio frequency (RF) transmitter located within the human body. This paper presents a modified Levenberg-Marquardt algorithm to reconstruct the dielectric profile with this new system architecture. Each antenna around the body acts both as a transmitter and a receiver for the remaining array elements. In addition, each antenna also acts as a receiver for the capsule transmitter inside the body to collect additional data which cannot be obtained from the conventional system. In this paper, the synthetic data are collected from biological objects, which are simulated for the circular phantoms using CST studio software. For the imaging part, the Levenberg-Marquardt algorithm, which is a kind of Newton inversion method, is chosen to reconstruct the dielectric profile of the objects. The imaging process involves a two-part innovation. The first part is the use of a dual mesh method which builds a dense mesh grid around in the region around the transmitter and a coarse mesh for the remaining area. The second part is the modification of the Levenberg-Marquardt method to use the additional data collected from the inside transmitter. The results show that the new system with the new imaging algorithm can obtain high resolution images even for small tumors.

  12. Development of advanced multi-tone mask by using two different transmittance modulation materials

    Science.gov (United States)

    Kim, Sei-Min; Choi, Min-Ki; Seo, Seong-Min; Lee, Jong-Hwa; Shin, Cheol; Jeong, Woo-Gun; Jung, Sung-Mo; Nam, Kee-Soo

    2016-09-01

    Multi-tone mask (MTM) consists of more than two layers having different transmittance modulation layers. A novel method is proposed to manufacture a MTM based on two kinds of transmittance modulation materials such as chromium and molybdenum. Different modulation materials cannot be only act as etch-stopper to each other, but also they play a role as a separator between the layers consisted of MTM. Furthermore, clearly classified modulation layers contribute to define one of the targeted transmittance according to different etching process. Especially, a conventional MTM requires three mask writing processes to form three patterns whereas the proposed MTM structure makes it possible to form three patterns by using only two mask writing processes. It is found that the turnaround time of proposed MTM is remarkably decreased as value of 30% compared to that of conventional MTM. MoSi-/Cr-based tri-tone mask configuration having 37, 15, and 0% of transmittance had been demonstrated based on the optimized thin-film conditions. Optical uniformity characteristics were also carried out to evaluate the photomask performance. Consequently, the proposed MTM is not only expected to extend the variation of objective transmittance, but also it is a very promise method for achieving a high performance photo-mask by reducing its fabrication cost.

  13. Comparative study on earthquake and ground based transmitter induced radiation belt electron precipitation at middle latitudes

    Directory of Open Access Journals (Sweden)

    N. F. Sidiropoulos

    2011-07-01

    Full Text Available We examined (peak-to-background flux ratio p/b > 20 energetic electron bursts in the presence of VLF activity, as observed from the DEMETER satellite at low altitudes (~700 km. Our statistical analysis of measurements during two 6-month periods suggests that: (a the powerful transmitter NWC causes the strongest effects on the inner radiation belts in comparison with other ground-based VLF transmitters, (b the NWC transmitter was responsible for only ~1.5 % of total electron bursts examined during the 6-month period (1 July 2008 to 31 December 2008, (c VLF transmitter-related electron bursts are accompanied by the presence of a narrow band emission centered at the radiating frequency emission, whereas the earthquake-related electron bursts are accompanied by the presence of broadband emissions from a few kHz to >20 KHz, (d daytime events are less preferable than nighttime events, but this asymmetry was found to be less evident when the powerful transmitter NWC was turned off and (d seismic activity most probably dominated the electromagnetic interactions producing the electron precipitation at middle latitudes. The results of this study support the proposal that the detection of radiation belt electron precipitation, besides other kinds of studies, is a useful tool for earthquake prediction research.

  14. Glutamate may be an efferent transmitter that elicits inhibition in mouse taste buds.

    Directory of Open Access Journals (Sweden)

    Yijen A Huang

    Full Text Available Recent studies suggest that l-glutamate may be an efferent transmitter released from axons innervating taste buds. In this report, we determined the types of ionotropic synaptic glutamate receptors present on taste cells and that underlie this postulated efferent transmission. We also studied what effect glutamate exerts on taste bud function. We isolated mouse taste buds and taste cells, conducted functional imaging using Fura 2, and used cellular biosensors to monitor taste-evoked transmitter release. The findings show that a large fraction of Presynaptic (Type III taste bud cells (∼50% respond to 100 µM glutamate, NMDA, or kainic acid (KA with an increase in intracellular Ca(2+. In contrast, Receptor (Type II taste cells rarely (4% responded to 100 µM glutamate. At this concentration and with these compounds, these agonists activate glutamatergic synaptic receptors, not glutamate taste (umami receptors. Moreover, applying glutamate, NMDA, or KA caused taste buds to secrete 5-HT, a Presynaptic taste cell transmitter, but not ATP, a Receptor cell transmitter. Indeed, glutamate-evoked 5-HT release inhibited taste-evoked ATP secretion. The findings are consistent with a role for glutamate in taste buds as an inhibitory efferent transmitter that acts via ionotropic synaptic glutamate receptors.

  15. Abdominally implanted transmitters with percutaneous antennas affect the dive performance of Common Eiders

    Science.gov (United States)

    Powell, Abby N.; Latty, Christopher J.; Hollmén, Tuula E.; Petersen, Margaret R.; Andrews, Russel D.

    2010-01-01

    Implanted transmitters have become an important tool for studying the ecology of sea ducks, but their effects remain largely undocumented. To address this, we assessed how abdominally implanted transmitters with percutaneous antennas affect the vertical dive speeds, stroke frequencies, bottom time, and dive duration of captive Common Eiders (Somateria mollissima). To establish baselines, we recorded video of six birds diving 4.9 m prior to surgery, implanted them with 38- to 47-g platform transmitter terminals, and then recorded their diving for 3.5 months after surgery to determine effects. Descent speeds were 16–25% slower and ascent speeds were 17–44% slower after surgery, and both remained below baseline at the end of the study. Dive durations were longer than baseline until day 22. On most days between 15 and 107 days after surgery, foot-stroke frequencies of birds foraging on the bottom were slower. Foot- and wing-stroke frequencies during descent and bottom time did not differ across the time series. If birds that rely on benthic invertebrates for sustenance dive slower and stay submerged longer after being implanted with a satellite transmitter, their foraging energetics may be affected. Researchers considering use of implanted transmitters with percutaneous antennas should be mindful of these effects and the possibility of concomitant alterations in diving behavior, foraging success, and migratory behavior compared to those of unmarked conspecifics.

  16. Assessment of Barotrauma from Rapid Decompression of Depth-Acclimated Juvenile Chinook Salmon Bearing Radiotelemetry Transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Carlson, Thomas J.; Welch, Abigail E.; Stephenson, John R.; Abernethy, Cary S.; Ebberts, Blaine D.; Langeslay, Mike; Ahmann, Martin L.; Feil, Daniel H.; Skalski, J. R.; Townsend, Richard L.

    2009-11-01

    This study investigated the mortality of and injury to juvenile Chinook salmon Oncorhynchus tshawytscha exposed to simulated pressure changes associated with passage through a large Kaplan hydropower turbine. Mortality and injury varied depending on whether a fish was carrying a transmitter, the method of transmitter implantation, the depth of acclimation, and the size of the fish. Juvenile Chinook salmon implanted with radio transmitters were more likely than those without to die or sustain injuries during simulated turbine passage. Gastric transmitter implantation resulted in higher rates of injury and mortality than surgical implantation. Mortality and injury increased with increasing pressure of acclimation. Injuries were more common in subyearling fish than in yearling fish. Gas emboli in the gills and internal hemorrhaging were the major causes of mortality. Rupture of the swim bladder and emphysema in the fins were also common. This research makes clear that the exposure of juvenile Chinook salmon bearing radiotelemetry transmitters to simulated turbine pressures with a nadir of 8-19 kPa can result in barotrauma, leading to immediate or delayed mortality. The study also identified sublethal barotrauma injuries that may increase susceptibility to predation. These findings have significant implications for many studies that use telemetry devices to estimate the survival and behavior of juvenile salmon as they pass through large Kaplan turbines typical of those within the Columbia River hydropower system. Our results indicate that estimates of turbine passage survival for juvenile Chinook salmon obtained with radiotelemetry devices may be negatively biased.

  17. Fiber-Based, Trace-Gas, Laser Transmitter Technology Development for Space

    Science.gov (United States)

    Stephen, Mark; Yu, Anthony; Chen, Jeffrey; Nicholson, Jeffrey; Engin, Doruk; Mathason, Brian; Wu, Stewart; Allan, Graham; Hasselbrack, William; Gonzalez, Brayler; Han, Lawrence; Numata, Kenji; Storm, Mark; Abshire, James

    2015-01-01

    NASA’s Goddard Space Flight Center (GSFC) is working on maturing the technology readiness of a laser transmitter designed for use in atmospheric CO2 remote-sensing. GSFC has been developing an airplane-based CO2 lidar instrument over several years to demonstrate the efficacy of the instrumentation and measurement technique and to link the science models to the instrument performance. The ultimate goal is to make space-based satellite measurements with global coverage. In order to accomplish this, we must demonstrate the technology readiness and performance of the components as well as demonstrate the required power-scaling to make the link with the required signal-to-noise-ratio (SNR). To date, all the instrument components have been shown to have the required performance with the exception of the laser transmitter.In this program we are working on a fiber-based master oscillator power amplifier (MOPA) laser transmitter architecture where we will develop a ruggedized package and perform the relevant environmental tests to demonstrate TRL-6. In this paper we will review our transmitter architecture and progress on the performance and packaging of the laser transmitter.

  18. Post-release survival and movement of Western Grebes (Aechmophorus occidentalis) implanted with intracoelomic satellite transmitters

    Science.gov (United States)

    Mills, Kyra L.; Gaydos, Joseph K.; Fiorello, Christine V.; Whitmer, Emily; De La Cruz, Susan; Mulcahy, Daniel M.; Vilchis, L. Ignacio; Ziccardi, Michael H.

    2016-01-01

    The main goal of this study was to gain knowledge on post-release survival and movement of Western Grebes (Aechmophorus occidentalis) using a modified technique for implanting satellite transmitters. This technique had improved post-surgical survival in an earlier study. Nine Western Grebes, implanted with intracoelomic (within the body cavity) satellite transmitters with percutaneous antennae, were released close to their capture site in San Francisco Bay, California, USA. Eight survived at least 25 days (average number of transmittal days was 140.8), while two had transmitters that provided data for greater than 1 year (436 and 454 days). The average cumulative distance recorded for all Western Grebes (n = 9) was 829 km with two round-trip movements documented. One individual Western Grebe traveled a cumulative round-trip distance of 2,144 km in July and November 2011, while another individual traveled a round-trip distance of 1,514 km between 8 and 14 December 2011. This study provides a step forward in testing implantable satellite transmitters in Western Grebes and highlights the need to further improve tracking methods, potentially improving our understanding of their population threats.

  19. Nonlethal gill biopsy does not affect juvenile chinook salmon implanted with radio transmitters

    Science.gov (United States)

    Martinelli-Liedtke, T. L.; Shively, R.S.; Holmberg, G.S.; Sheer, M.B.; Schrock, R.M.

    1999-01-01

    Using gastric and surgical transmitter implantation, we compared radio-tagged juvenile chinook salmon Oncorhynchus tshawytscha (T(O)) with tagged fish also having a gill biopsy (T(B)) to determine biopsy effects on fish implanted with radio transmitters. We found no evidence during the 21-d period to suggest that a gill biopsy reduced survival, growth, or gross condition of the tagged-biopsy group, regardless of transmitter implantation technique. We recorded 100% survival of all treatment groups. Relative growth rates of T(O) and T(B) fish did not differ significantly. Leukocrit and lysozyme levels were not significantly different among groups, suggesting that no signs of infection were present. Our findings suggest that small chinook salmon can tolerate the combination of transmitter implantation and gill biopsy without compromising condition relative to fish receiving only the transmitter. We believe a gill biopsy can be used in field telemetry studies, especially when physiological data are needed in addition to behavioral data.

  20. Effects of surgically implanted dummy transmitters on the South American catfish Jundiá (Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Schulz U. H.

    2003-01-01

    Full Text Available High water temperatures and low water quality may negatively influence wound healing, growth and transmitter retention in radio-tagged fish of tropical and subtropical water bodies which in turn may hamper radio tracking studies. For a period of 90 days, we compared growth of an experimental group of ten Rhamdia quelen, which were submitted to intraperitoneal dummy transmitter implantation, with that of a control group. Additionally, wound healing and transmitter expulsion were observed in the experimental group. Water temperature varied between 24degreesC and 30degreesC during the study. Experimental group and control fish decreased in body weight during the investigation period, but the differences between the mean individual weight loss in both groups were not significant (Student t-test, p = 0.64. Wound healing in experiment group fish was advanced after 14 days, while after 70 days eight out of ten incision wounds were closed and cicatrized. One fish had its dummy transmitter expulsed through the ventral body wall. After 90 days two more fish had the dummies expulsed, one through the ventral body wall and the other through the antenna exit. One experimental group fish died with visible signs of infection. The results encourage the use of surgically implanted radio transmitters for long-term tagging studies at high water temperatures.

  1. Effects of surgically implanted dummy transmitters on the South American catfish Jundiá (Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    U. H. Schulz

    Full Text Available High water temperatures and low water quality may negatively influence wound healing, growth and transmitter retention in radio-tagged fish of tropical and subtropical water bodies which in turn may hamper radio tracking studies. For a period of 90 days, we compared growth of an experimental group of ten Rhamdia quelen, which were submitted to intraperitoneal dummy transmitter implantation, with that of a control group. Additionally, wound healing and transmitter expulsion were observed in the experimental group. Water temperature varied between 24°C and 30°C during the study. Experimental group and control fish decreased in body weight during the investigation period, but the differences between the mean individual weight loss in both groups were not significant (Student t-test, p = 0.64. Wound healing in experiment group fish was advanced after 14 days, while after 70 days eight out of ten incision wounds were closed and cicatrized. One fish had its dummy transmitter expulsed through the ventral body wall. After 90 days two more fish had the dummies expulsed, one through the ventral body wall and the other through the antenna exit. One experimental group fish died with visible signs of infection. The results encourage the use of surgically implanted radio transmitters for long-term tagging studies at high water temperatures.

  2. Measurement device for high-precision spectral transmittance of solar blind filter

    Science.gov (United States)

    Wang, Yan; Qian, Yunsheng; Lv, Yang; Feng, Cheng; Liu, Jian

    2017-02-01

    In order to measure spectral transmittance of solar-blind filter ranging from ultraviolet to visible light accurately, a high-precision filter transmittance measuring system based on the ultraviolet photomultiplier is developed. The calibration method is mainly used to measure transmittance in this system, which mainly consists of an ultraviolet photomultiplier as core of the system and a lock-in amplifier combined with an optical modulator as the aided measurement for the system. The ultraviolet photomultiplier can amplify the current signal through the filter and have the characteristics of low dark current and high luminance gain. The optical modulator and the lock-in amplifier can obtain the signal from the photomultiplier and inhibit dark noise and spurious signal effectively. Through these two parts, the low light passing through the filters can be detected and we can calculate the transmittance by the optical power detected. Based on the proposed system, the limit detection of the transmittance can reach 10-12, while the result of the conventional approach is merely 10-6. Therefore, the system can make an effective assessment of solar blind ultraviolet filters.

  3. Improving the Transmittance of an Epsilon-Near-Zero based Wavefront Shaper

    CERN Document Server

    Briere, G; Demichel, O

    2016-01-01

    Although Epsilon-Near-Zero metamaterials (ENZ) offer many unconventional ways to play with light, the optical impedance mismatch with surroundings can limit the efficiency of future devices. We report here on the improvement of the transmittance of an Epsilon-Near-Zero (ENZ) wavefront shaper. We first address in this paper the way to enhance the transmittance of a plane wave through a layer of ENZ material thanks to a numerical optimization approach based on the Transfer Matrix Method. We then transpose the one dimensional approach to a two dimensional case where the emission of a dipole is shaped into a plane wave by an ENZ device with a design that optimizes the transmittance. As a result, we demonstrate a transmittance efficiency of 15 \\% that is 4 orders of magnitude higher than previous devices proposed in the literature for wavefront shaping applications. This work aims at paving the way for future efficient ENZ devices by offering new strategies to optimize the transmittance through ENZ materials.

  4. Environmental Assessment - Construct a Ground-to-Air Transmitter and Receiver (GATR) Facility at Grand Forks Air Force Base

    Science.gov (United States)

    2006-06-06

    for wildlife in Grand Forks County. Pastures, meadows, and other non- cultivated areas create a prairie-land mosaic of grasses, legumes, and wild... alfalfa . Herbaceous plants include little bluestem, goldenrod, green needle grass, western wheat grass, and bluegrama. Shrubs such as Juneberry...consists primarily of cultivated crops with remaining land used for pasture and hay, urban development, recreation, and wildlife habitat. Principal

  5. Facility Registry Service (FRS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Facility Registry Service (FRS) provides an integrated source of comprehensive (air, water, and waste) environmental information about facilities across EPA,...

  6. Licensed Healthcare Facilities

    Data.gov (United States)

    California Department of Resources — The Licensed Healthcare Facilities point layer represents the locations of all healthcare facilities licensed by the State of California, Department of Health...

  7. High Throughput Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Argonne?s high throughput facility provides highly automated and parallel approaches to material and materials chemistry development. The facility allows scientists...

  8. Aperture area measurement facility

    Data.gov (United States)

    Federal Laboratory Consortium — NIST has established an absolute aperture area measurement facility for circular and near-circular apertures use in radiometric instruments. The facility consists of...

  9. Environmental Toxicology Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Fully-equipped facilities for environmental toxicology research The Environmental Toxicology Research Facility (ETRF) located in Vicksburg, MS provides over 8,200 ft...

  10. Licensed Healthcare Facilities

    Data.gov (United States)

    California Department of Resources — The Licensed Healthcare Facilities point layer represents the locations of all healthcare facilities licensed by the State of California, Department of Health...

  11. Yule-Nielsen based recto-verso color halftone transmittance prediction model.

    Science.gov (United States)

    Hébert, Mathieu; Hersch, Roger D

    2011-02-01

    The transmittance spectrum of halftone prints on paper is predicted thanks to a model inspired by the Yule-Nielsen modified spectral Neugebauer model used for reflectance predictions. This model is well adapted for strongly scattering printing supports and applicable to recto-verso prints. Model parameters are obtained by a few transmittance measurements of calibration patches printed on one side of the paper. The model was verified with recto-verso specimens printed by inkjet with classical and custom inks, at different halftone frequencies and on various types of paper. Predictions are as accurate as those obtained with a previously developed reflectance and transmittance prediction model relying on the multiple reflections of light between the paper and the print-air interfaces. Optimal n values are smaller in transmission mode compared with the reflection model. This indicates a smaller amount of lateral light propagation in the transmission mode.

  12. An empirical model for estimating the atmospheric transmittance of upward infrared radiation at different altitudes

    Science.gov (United States)

    Dai, Qiumin; Fang, Xiande; Zhao, Yingjie; Xing, Daoming

    2016-12-01

    The upward infrared (IR) radiation is one of the most important factors that affect the thermal characteristics of light-than-air (LTA) vehicles. Therefore, it is necessary to propose an accurate model to evaluate the upward atmospheric transmittance. The upward IR atmospheric transmittances of 6 different atmospheric models at the altitude from sea level to 30 km are obtained from the MODTRAN atmospheric radiative transfer code. Based on the data, a new upward IR atmospheric transmittance correlation related to pressure and vertical water column is proposed by regression analysis. It has excellent prediction accuracy with the coefficient of determination of 0.928, the root mean square error of 0.028, and the mean absolute percentage error of 2.68% for the database. Based on the new correlation, the thermal characteristics of a stratospheric airship located in tropics in midsummer are numerical studied and discussed.

  13. NOVEL TECHNIQUE OF POWER CONTROL IN MAGNETRON TRANSMITTERS FOR INTENSE ACCELERATORS

    Energy Technology Data Exchange (ETDEWEB)

    Kazakevich, G. [MUONS Inc., Batavia; Johnson, R. [MUONS Inc., Batavia; Neubauer, M.; Lebedev, V. [Fermilab; Schappert, W. [Fermilab; Yakovlev, V. [Fermilab

    2016-10-21

    A novel concept of a high-power magnetron transmitter allowing dynamic phase and power control at the frequency of locking signal is proposed. The transmitter compensating parasitic phase and amplitude modulations inherent in Superconducting RF (SRF) cavities within closed feedback loops is intended for powering of the intensity-frontier superconducting accelerators. The con- cept uses magnetrons driven by a sufficient resonant (in- jection-locking) signal and fed by the voltage which can be below the threshold of self-excitation. This provides an extended range of power control in a single magnetron at highest efficiency minimizing the cost of RF power unit and the operation cost. Proof-of-principle of the proposed concept demonstrated in pulsed and CW regimes with 2.45 GHz, 1kW magnetrons is discussed here. A conceptual scheme of the high-power transmitter allowing the dynamic wide-band phase and y power controls is presented and discussed.

  14. Methods of Phase and Power Control in Magnetron Transmitters for Superconducting Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Kazadevich, G. [MUONS Inc., Batavia; Johnson, R. [MUONS Inc., Batavia; Neubauer, M. [MUONS Inc., Batavia; Lebedev, V. [Fermilab; Schappert, W. [Fermilab; Yakovlev, V. [Fermilab

    2017-05-01

    Various methods of phase and power control in magnetron RF sources of superconducting accelerators intended for ADS-class projects were recently developed and studied with conventional 2.45 GHz, 1 kW, CW magnetrons operating in pulsed and CW regimes. Magnetron transmitters excited by a resonant (injection-locking) phasemodulated signal can provide phase and power control with the rates required for precise stabilization of phase and amplitude of the accelerating field in Superconducting RF (SRF) cavities of the intensity-frontier accelerators. An innovative technique that can significantly increase the magnetron transmitter efficiency at the widerange power control required for superconducting accelerators was developed and verified with the 2.45 GHz magnetrons operating in CW and pulsed regimes. High efficiency magnetron transmitters of this type can significantly reduce the capital and operation costs of the ADSclass accelerator projects.

  15. Transmitter and translating receiver design for 64-ary pulse position modulation (PPM)

    Science.gov (United States)

    Mendez, Antonio J.; Hernandez, Vincent J.; Gagliardi, Robert M.; Bennett, Corey V.

    2010-02-01

    This paper explores the architecture and design of an optically-implemented 64-ary PPM transmitter and direct-translating receiver that effectively translates incoming electrically-generated bit streams into optical PPM symbols (and vice-versa) at > 1 Gb/s data rates. The PPM transmitter is a cascade of optical switches operating at the frame rate. A corresponding receiver design is more difficult to architect and implement, since increasing data rates lead to correspondingly shorter decision times (slot times and frame times). We describe a solution in the form of a time-to-space mapping arrayed receiver that performs a translating algorithm represented as a code map. The technique for generating the code map is described, and the implementation of the receiver as a planar lightwave circuit is given. The techniques for implementing the transmitter and receiver can be generalized for any case of M-ary PPM.

  16. Transmitter and Translating Receiver Design For 64-ary Pulse Position Modulation (PPM)

    Energy Technology Data Exchange (ETDEWEB)

    Mendez, A J; Hernandez, V J; Gagliardi, R M; Bennett, C V

    2010-01-20

    This paper explores the architecture and design of an optically-implemented 64-ary PPM transmitter and direct-translating receiver that effectively translates incoming electrically-generated bit streams into optical PPM symbols (and vice-versa) at > 1 Gb/s data rates. The PPM transmitter is a cascade of optical switches operating at the frame rate. A corresponding receiver design is more difficult to architect and implement, since increasing data rates lead to correspondingly shorter decision times (slot times and frame times). We describe a solution in the form of a time-to-space mapping arrayed receiver that performs a translating algorithm represented as a code map. The technique for generating the code map is described, and the implementation of the receiver as a planar lightwave circuit is given. The techniques for implementing the transmitter and receiver can be generalized for any case of M-ary PPM.

  17. Ultra-low-power wireless transmitter for neural prostheses with modified pulse position modulation.

    Science.gov (United States)

    Goodarzy, Farhad; Skafidas, Stan E

    2014-01-01

    An ultra-low-power wireless transmitter for embedded bionic systems is proposed, which achieves 40 pJ/b energy efficiency and delivers 500 kb/s data using the medical implant communication service frequency band (402-405 MHz). It consumes a measured peak power of 200 µW from a 1.2 V supply while occupying an active area of 0.0016 mm(2) in a 130 nm technology. A modified pulse position modulation technique called saturated amplified signal is proposed and implemented, which can reduce the overall and per bit transferred power consumption of the transmitter while reducing the complexity of the transmitter architectures, and hence potentially shrinking the size of the implemented circuitry. The design is capable of being fully integrated on single-chip solutions for surgically implanted bionic systems, wearable devices and neural embedded systems.

  18. Influence of externally attached transmitters on the swimming performance of juvenile white sturgeon

    Science.gov (United States)

    Counihan, T.D.; Frost, C.N.

    1999-01-01

    We measured the critical swimming speed of juvenile white sturgeons Acipenser transmontanus equipped with externally attached dummy ultrasonic transmitters and of untagged control fish in the laboratory. White sturgeons ranging from 31.9 to 37.0 cm fork length were subjected to one of three treatments: control (handled but not tagged), tag attached below the dorsal fin, and tag attached with the anterior insertion point between the fourth and fifth dorsal scutes. Although transmitters were of recommended weight, we found that the swimming performance of tagged white sturgeons was significantly less than that of untagged control fish. Swimming performance of tagged fish was not differentially affected by tag location. Our results suggest that data from ultrasonic telemetry studies of externally tagged juvenile white sturgeons should be interpreted with caution due to the reduced swimming performance caused by external transmitters.

  19. Optimal position of the transmitter coil for wireless power transfer to the implantable device.

    Science.gov (United States)

    Jinghui Jian; Stanaćević, Milutin

    2014-01-01

    The maximum deliverable power through inductive link to the implantable device is limited by the tissue exposure to the electromagnetic field radiation. By moving away the transmitter coil from the body, the maximum deliverable power is increased as the magnitude of the electrical field at the interface with the body is kept constant. We demonstrate that the optimal distance between the transmitter coil and the body is on the order of 1 cm when the current of the transmitter coil is limited to 1 A. We also confirm that the conditions on the optimal frequency of the power transmission and the topology of the transmission coil remain the same as if the coil was directly adjacent to the body.

  20. Microscopically crumpled indium-tin-oxide thin films as compliant electrodes with tunable transmittance

    Energy Technology Data Exchange (ETDEWEB)

    Ong, Hui-Yng [School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798 (Singapore); School of Engineering, Nanyang Polytechnic, Singapore 569830 (Singapore); Shrestha, Milan; Lau, Gih-Keong, E-mail: mgklau@ntu.edu.sg [School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

    2015-09-28

    Indium-tin-oxide (ITO) thin films are perceived to be stiff and brittle. This letter reports that crumpled ITO thin films on adhesive poly-acrylate dielectric elastomer can make compliant electrodes, sustaining compression of up to 25% × 25% equi-biaxial strain and unfolding. Its optical transmittance reduces with crumpling, but restored with unfolding. A dielectric elastomer actuator (DEA) using the 14.2% × 14.2% initially crumpled ITO thin-film electrodes is electrically activated to produce a 37% areal strain. Such electric unfolding turns the translucent DEA to be transparent, with transmittance increased from 39.14% to 52.08%. This transmittance tunability promises to make a low-cost smart privacy window.

  1. Probing the intracellular calcium sensitivity of transmitter release during synaptic facilitation.

    Science.gov (United States)

    Felmy, Felix; Neher, Erwin; Schneggenburger, Ralf

    2003-03-06

    In nerve terminals, residual Ca(2+) remaining from previous activity can cause facilitation of transmitter release by a mechanism that is still under debate. Here we show that the intracellular Ca(2+) sensitivity of transmitter release at the calyx of Held is largely unchanged during facilitation, which leaves an increased microdomain Ca(2+) signal as a possible mechanism for facilitation. We measured the Ca(2+) dependencies of facilitation, as well as of transmitter release, to estimate the required increment in microdomain Ca(2+). These measurements show that linear summation of residual and microdomain Ca(2+) accounts for only 30% of the observed facilitation. However, a small degree of supralinearity in the summation of intracellular Ca(2+) signals, which might be caused by saturation of cytosolic Ca(2+) buffer(s), is sufficient to explain facilitation at this CNS synapse.

  2. On the Capacity of Compound State-Dependent Channels with States Known at the Transmitter

    CERN Document Server

    Piantanida, Pablo

    2010-01-01

    This paper investigates the capacity of compound state-dependent channels with non-causal state information available at only the transmitter. A new lower bound on the capacity of this class of channels is derived. This bound is shown to be tight for the special case of compound channels with stochastic degraded components, yielding the full characterization of the capacity. Specific results are derived for the compound Gaussian Dirty-Paper (GDP) channel. This model consists of an additive white Gaussian noise (AWGN) channel corrupted by an additive Gaussian interfering signal, known at the transmitter only, where the input and the state signals are affected by fading coefficients whose realizations are unknown at the transmitter. Our bounds are shown to be tight for specific cases. Applications of these results arise in a variety of wireless scenarios as multicast channels, cognitive radio and problems with interference cancellation.

  3. Surgically Implanted JSATS Micro-Acoustic Transmitters Effects on Juvenile Chinook Salmon and Steelhead Tag Expulsion and Survival, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, Christa M.; Carpenter, Scott M.; Carter, Kathleen M.; Wagner, Katie A.; Royer, Ida M.; Knox, Kasey M.; Kim, Jin A.; Gay, Marybeth E.; Weiland, Mark A.; Brown, Richard S.

    2011-09-16

    The purpose of this study was to evaluate survival model assumptions associated with a concurrent study - Acoustic Telemetry Evaluation of Dam Passage Survival and Associated Metrics at John Day, The Dalles, and Bonneville Dams, 2010 by Thomas Carlson and others in 2010 - in which the Juvenile Salmonid Acoustic Telemetry System (JSATS) was used to estimate the survival of yearling and subyearling Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) migrating through the Federal Columbia River Power System (FCRPS). The micro-acoustic transmitter used in these studies is the smallest acoustic transmitter model to date (12 mm long x 5 mm wide x 4 mm high, and weighing 0.43 g in air). This study and the 2010 study by Carlson and others were conducted by researchers from the Pacific Northwest National Laboratory and the University of Washington for the U.S. Army Corps of Engineers, Portland District, to meet requirements set forth by the 2008 FCRPS Biological Opinion. In 2010, we compared survival, tag burden, and tag expulsion in five spring groups of yearling Chinook salmon (YCH) and steelhead (STH) and five summer groups of subyearling Chinook salmon (SYC) to evaluate survival model assumptions described in the concurrent study. Each tagging group consisted of approximately 120 fish/species, which were collected and implanted on a weekly basis, yielding approximately 600 fish total/species. YCH and STH were collected and implanted from late April to late May (5 weeks) and SYC were collected and implanted from mid-June to mid-July (5 weeks) at the John Day Dam Smolt Monitoring Facility. The fish were collected once a week, separated by species, and assigned to one of three treatment groups: (1) Control (no surgical treatment), (2) Sham (surgical implantation of only a passive integrated transponder [PIT] tag), and (3) Tagged (surgical implantation of JSATS micro-acoustic transmitter [AT] and PIT tags). The test fish were held for 30 days in indoor

  4. Guide to research facilities

    Energy Technology Data Exchange (ETDEWEB)

    1993-06-01

    This Guide provides information on facilities at US Department of Energy (DOE) and other government laboratories that focus on research and development of energy efficiency and renewable energy technologies. These laboratories have opened these facilities to outside users within the scientific community to encourage cooperation between the laboratories and the private sector. The Guide features two types of facilities: designated user facilities and other research facilities. Designated user facilities are one-of-a-kind DOE facilities that are staffed by personnel with unparalleled expertise and that contain sophisticated equipment. Other research facilities are facilities at DOE and other government laboratories that provide sophisticated equipment, testing areas, or processes that may not be available at private facilities. Each facility listing includes the name and phone number of someone you can call for more information.

  5. Examination of an Optical Transmittance Test for Photovoltaic Encapsulation Materials: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D. C.; Bengoechea, J.; Bokria, J. G.; Kohl, M.; Powell, N. E.; Smith, M. E.; White, M. D.; Wilson, H. R.; Wohlgemuth, J. H.

    2013-09-01

    The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and more appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).

  6. Examination of an Optical Transmittance Test for Photovoltaic Encapsulation Materials (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.; Bengoechea, J.; Bokria, J.; Kohl, M.; Powell, N. E.; Smith, M. E.; White, M. D.; Wilson, H. R.; Wohlgemuth, J. H.

    2013-09-01

    The optical transmittance of encapsulation materials is a key characteristic for their use in photovoltaic (PV) modules. Changes in transmittance with time in the field affect module performance, which may impact product warranties. Transmittance is important in product development, module manufacturing, and field power production (both immediate and long-term). Therefore, an international standard (IEC 62788-1-4) has recently been proposed by the Encapsulation Task-Group within the Working Group 2 (WG2) of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC82) for the quantification of the optical performance of PV encapsulation materials. Existing standards, such as ASTM E903, are general and more appropriately applied to concentrated solar power than to PV. Starting from the optical transmittance measurement, the solar-weighted transmittance of photon irradiance, yellowness index (which may be used in aging studies to assess durability), and ultraviolet (UV) cut-off wavelength may all be determined using the proposed standard. The details of the proposed test are described. The results of a round-robin experiment (for five materials) conducted at seven laboratories to validate the test procedure using representative materials are also presented. For example, the Encapsulation Group actively explored the measurement requirements (wavelength range and resolution), the requirements for the spectrophotometer (including the integrating sphere and instrument accessories, such as a depolarizer), specimen requirements (choice of glass-superstrate and -substrate), and data analysis (relative to the light that may be used in the PV application). The round-robin experiment identified both intra- and inter-laboratory instrument precision and bias for five encapsulation materials (encompassing a range of transmittance and haze-formation characteristics).

  7. Extended lateral heating of the nighttime ionosphere by ground-based VLF transmitters

    OpenAIRE

    İnan, Umran Savaş; Graf, K. L.; Spasojevic, M.; Marshall, R. A.; Lehtinen, N. G.; Foust, F. R.

    2013-01-01

    JOURNAL OF GEOPHYSICAL RESEARCH: SPACE PHYSICS, VOL. 118, 7783–7797, doi:10.1002/2013JA019337, 2013 Extended lateral heating of the nighttime ionosphere by ground-based VLF transmitters K. L. Graf,1 M. Spasojevic,1 R. A. Marshall,2 N. G. Lehtinen,1 F. R. Foust,1 and U. S. Inan1,3 Received 16 August 2013; revised 9 October 2013; accepted 11 November 2013; published 3 December 2013. [1] The effects of ground-based very low frequency (VLF) transmitters on the lower ionospher...

  8. Design and Implementation of Double-Transmitter-Coil Antenna Used for the Tag Test System

    Directory of Open Access Journals (Sweden)

    Bin You

    2013-01-01

    Full Text Available At present, more and more electronic tags are used in Antitheft system; it is important to examine the performance of electronic tags. The traditional single-transmitter-coil antenna (STC antenna of the electronic tags tester has some serious drawbacks. So a novel double-transmitter-coil antenna (DTC antenna is presented in this paper. Compared to the traditional STC antenna, this new antenna has a more excellent performance in the tag test systems, especially when it is used for testing the quality factor of tags.

  9. Transmittance of transparent windows with non-absorbing cap-shaped droplets condensed on their backside

    Science.gov (United States)

    Zhu, Keyong; Huang, Yong; Pruvost, Jeremy; Legrand, Jack; Pilon, Laurent

    2017-06-01

    This study aims to quantify systematically the effect of non-absorbing cap-shaped droplets condensed on the backside of transparent windows on their directional-hemispherical transmittance and reflectance. Condensed water droplets have been blamed to reduce light transfer through windows in greenhouses, solar desalination plants, and photobioreactors. Here, the directional-hemispherical transmittance was predicted by Monte Carlo ray-tracing method. For the first time, both monodisperse and polydisperse droplets were considered, with contact angle between 0 and 180°, arranged either in an ordered hexagonal pattern or randomly distributed on the window backside with projected surface area coverage between 0 and 90%. The directional-hemispherical transmittance was found to be independent of the size and spatial distributions of the droplets. Instead, it depended on (i) the incident angle, (ii) the optical properties of the window and droplets, and on (iii) the droplet contact angle and (iv) projected surface area coverage. In fact, the directional-hemispherical transmittance decreased with increasing incident angle. Four optical regimes were identified in the normal-hemispherical transmittance. It was nearly constant for droplet contact angles either smaller than the critical angle θcr (predicted by Snell's law) for total internal reflection at the droplet/air interface or larger than 180°-θcr. However, between these critical contact angles, the normal-hemispherical transmittance decreased rapidly to reach a minimum at 90° and increased rapidly with increasing contact angles up to 180°-θcr. This was attributed to total internal reflection at the droplet/air interface which led to increasing reflectance. In addition, the normal-hemispherical transmittance increased slightly with increasing projected surface area coverage for contact angle was smaller than θcr. However, it decreased monotonously with increasing droplet projected surface area coverage for contact

  10. System Design of a S-band Solid-state Transmitter in Satellite-borne SAR

    Directory of Open Access Journals (Sweden)

    Zhao Hai-yang

    2014-06-01

    Full Text Available The system design of a S-band solid-state transmitter in satellite-borne SAR is introduced. A series of critical technologies, such as high reliability, environmental adaptability, and structure miniaturization, which are necessary in satellite applications, are analyzed and discussed. The technologies are experimentally verified at different periods. Multichannel combined technology is used for the transmitter, and the output peak power is more than 3 kW. Because of the high efficiency, small size, lightweight, and high power, it is especially applicable in small satellite platforms.

  11. Prototype of a Dsp-Based Instrument for In-Service Wireless Transmitter Power Measurement

    Directory of Open Access Journals (Sweden)

    Angrisani Leopoldo

    2014-12-01

    Full Text Available A prototype of a DSP-based instrument for in-service transmitter power measurements is presented. The instrument implements a signal-selective algorithm for power measurements that is suitable for use in wireless environments, where possible uncontrolled interfering sources are present in the radio channel and are overlapped to the signal emitted by the transmitter under test, possibly in both time and frequency domain. The measurement method exploits the principles of cyclic spectral analysis, which are briefly recalled in the paper. Potentialities, as well as limitations of the prototype use are discussed, and the results of experiments with both modulated and unmodulated interfering sources are presented.

  12. Phase thickness approach for determination of thin film refractive index dispersion from transmittance spectra

    Science.gov (United States)

    Nenkov, M. R.; Pencheva, T. G.

    2008-06-01

    A novel approach for determination of refractive index dispersion n(λ ) and thickness d of thin films of negligible absorption and weak dispersion is proposed. The calculation procedure is based on determination of the phase thickness of the film in the spectral region of measured transmittance data. All points of measured spectra are included in the calculations. Barium titanate and titanium oxide thin films are investigated and their n(λ ) and d are calculated. The approach is validated using Swanepoel's method and it is found to be applicable for relatively thinner films when measured transmittance spectra have one minimum and one maximum only.

  13. A novel Chirped Return-to-Zero Transmitter and Transmission Experiments

    DEFF Research Database (Denmark)

    Liu, Fenghai; Peucheret, Christophe; Xueyan, Zheng;

    2000-01-01

    A new 10 Gb/s chirped return-to-zero transmitter using CW light modulated by only one external modulator is proposed. Transmission over 3600 km of standard single mode fibre is performed in a re-circulating loop set-up with 80 km amplifier span.......A new 10 Gb/s chirped return-to-zero transmitter using CW light modulated by only one external modulator is proposed. Transmission over 3600 km of standard single mode fibre is performed in a re-circulating loop set-up with 80 km amplifier span....

  14. Conception and FPGA implementation of IEEE 802.11s mesh network MAC layer transmitter

    CERN Document Server

    Chaari, Lamia; Kamoun, Lotfi

    2010-01-01

    This paper proposes, a hardware implementation of Wireless Mesh Networks (WMN) medium Access Controller (MAC) layer transmitter. In the literature a lot of works are focused on WMN routing protocol as well as performance analysis and software integration of WMN units, however few works deals with WMN hardware implementation. In this field our contribution is to conceive and to implements on FPGA a WMN MAC transmitter module. Our implementation, written in hardware description language (HDL) is based on the IEEE 802.11 s standard. The hardware implementation retains a good performance in speed.

  15. Fiber-Based Laser Transmitter for Oxygen A-Band Spectroscopy and Remote Sensing

    Science.gov (United States)

    Stephen, Mark A.; Abshire, James B.

    2010-01-01

    A fiber-based laser transmitter has been designed for active remote-sensing spectroscopy. The transmitter uses a master-oscillator-power-amplifier (MOPA) configuration with a distributed feedback diode-laser master oscillator and an erbium-doped fiber amplifier. The output from the MOPA is frequency-doubled with a periodically poled nonlinear crystal. The utility of this single-frequency, wavelength-tunable, power-scalable laser has been demonstrated in a spectroscopic measurement of the diatomic oxygen A-band.

  16. Effect of La2O3 on Microstructure and Transmittance of Transparent Alumina Ceramics

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Optically transparent alumina ceramics were fabricated by conventional process and sintered without pressure in H2 atmosphere. The results indicate that relative densities of alumina specimens increase to theoretical densities (T.D.) with increasing content of La2O3. With increasing holding time during sintering, much less pores and larger grains were found in the sintered alumina samples. Higher transmittance was achieved in alumina codoped with MgO and La2O3 as compared with that doped with MgO only. The total-transmittance of alumina sample is up to 86% at a wavelength range of 300~800 nm.

  17. Simple atmospheric transmittance calculation based on a Fourier-transformed Voigt profile.

    Science.gov (United States)

    Kobayashi, Hirokazu

    2002-11-20

    A method of line-by-line transmission calculation for a homogeneous atmospheric layer that uses the Fourier-transformed Voigt profile is presented. The method is based on a pure Voigt function with no approximation and an interference term that takes into account the line-mixing effect. One can use the method to calculate transmittance, considering each line shape as it is affected by temperature and pressure, with a line database with an arbitrary wave-number range and resolution. To show that the method is feasible for practical model development, we compared the calculated transmittance with that obtained with a conventional model, and good consistency was observed.

  18. Reliable Facility Location Problem with Facility Protection.

    Science.gov (United States)

    Tang, Luohao; Zhu, Cheng; Lin, Zaili; Shi, Jianmai; Zhang, Weiming

    2016-01-01

    This paper studies a reliable facility location problem with facility protection that aims to hedge against random facility disruptions by both strategically protecting some facilities and using backup facilities for the demands. An Integer Programming model is proposed for this problem, in which the failure probabilities of facilities are site-specific. A solution approach combining Lagrangian Relaxation and local search is proposed and is demonstrated to be both effective and efficient based on computational experiments on random numerical examples with 49, 88, 150 and 263 nodes in the network. A real case study for a 100-city network in Hunan province, China, is presented, based on which the properties of the model are discussed and some managerial insights are analyzed.

  19. 75 FR 3448 - Office of Innovation and Improvement; Notice Extending the Deadline Date for Transmittal of...

    Science.gov (United States)

    2010-01-21

    ... Office of Innovation and Improvement; Notice Extending the Deadline Date for Transmittal of Applications... format (e.g., braille, large print, audiotape, or computer diskette) on request to the program contact...: January 15, 2010. James H. Shelton, III, Assistant Deputy Secretary for Innovation and Improvement...

  20. Widely Tunable Negative-Chirp SG-DBR Laser/EA-Modulated Transmitter

    Science.gov (United States)

    Raring, J. W.; Skogen, E. J.; Johansson, L. A.; Sysak, M. N.; Denbaars, S. P.; Coldren, L. A.

    2005-01-01

    Ten Gb/s low power penalty (DBR) laser/EAM transmitter. Large signal chirp measurements show negative chirp operation across the entire tuning range of the devices. An integration-oriented quantum-well-intermixing (QWI) process was employed for the realization of these devices.

  1. A beaded collar for dual micro GPS/VHF transmitter attachment to nutria

    Science.gov (United States)

    Haramis, G.M.; White, T.S.

    2011-01-01

    We report on the development of an approximately 85-g beaded collar for dual micro GPS/VHF transmitter attachment to semi-aquatic nutria (Myocastor coypus). Prototype collars were tested on captive nutria and refined during field trials. Central to the design was novel use of the VHF transmitter antenna as a collar. A circular collar was formed by passing the 44-cm antenna cable through a pre-made hole in the transmitter, leaving an approximately 16-cm upright antenna. GPS units were mounted separately via a hole in the base of each unit. For good satellite contact, GPS units (28 g) were maintained at the nape of the neck by counterbalance of the heavier VHF transmitters (50 g) positioned under the neck. To reduce friction, we lined the collar with alternate-sized plastic and, later, more durable nylon beads. The final collar configuration was worn for approximately 1 month deployments with only minor neck abrasion; one collar was worn successfully for 5 months. Foot entanglement remained the greatest risk of injury from the collar. By fitting collars tightly, we reduced the incidence of foot entanglement to 2 of 33 deployments (6%). Successful GPS tracks were acquired on 29 of 33 deployments (88%).

  2. Software-Defined Radio Global System for Mobile Communications Transmitter Development for Heterogeneous Network Vulnerability Testing

    Science.gov (United States)

    2013-12-01

    48  3.  Results .................................................................................................48  a.  GNU Radio ...56  b.  GNU Radio Collection...by GNU Radio of the baseband signal created by the GSM transmitter code mimicking the GSM BTS BCH prior to USRP transmission. The blue signal shows

  3. High Power mm-Wave Transmitter System for Radar or Telecommunications

    Science.gov (United States)

    Stride, S. L.; McMaster, R. L.; Pogorzelski, R. J.

    2003-01-01

    Future NASA deep space missions able to provide tens of kilo-watts of spacecraft DC power, make it feasible to employ high power RF telecommunications systems. Traditional flight systems (e.g., Cassini), constrained by limited DC power, used a single high-gain 4m Cassegrain reflector fed by a single lower power (20W) transmitter. Increased available DC power means that high power (1000 W) transmitters can be used. Rather than continue building traditional single-transmitter systems it now becomes feasible to engineer and build multi-element active arrays that can illuminate a dish. Illuminating a 2m dish with a spherical wavefront from an offset 1kW active array can provide sufficient ERP (Effective Radiated Power) when compared to a larger Cassegrain dish. Such a system has the advantage of lower mass, lower volume, improved reliability, less stringent pointing requirements, lower cost and risk. We propose to design and build a prototype Ka-band transmit antenna with an active sub-array using 125W TWTAs. The system could be applied to a telecommunications downlink or radar transmitter used for missions such as JIMO.

  4. TLEs and early VLF events: Simulating the important impact of transmitter-disturbance-receiver geometry

    Science.gov (United States)

    NaitAmor, S.; Ghalila, H.; Cohen, M. B.

    2017-01-01

    Early very low frequency (VLF) events are perturbations to subionospherically propagating VLF radio transmitters which sometimes occur when lightning activity is near the transmitter-receiver path. They are often correlated to Transient Luminous Events (TLEs). Recent analysis have focused on a new type of early events whose recovery time persists for many minutes, called LOng Recovery Events (LOREs). The underlying cause of these events is still unclear. Curiously, LOREs sometimes appear on only one path, while the same event observed on a different transmitter-receiver path does not indicate a LORE. In this paper we observe and simulate two cases of early signal perturbations: The first is a typical early VLF event, and the second is a LORE. Both were recorded by two AWESOME VLF receivers in North Africa on 12 December 2009, during the EuroSprite campaign. We combine observations with theoretical modeling to infer the electron density change that most closely reproduces the observed perturbation. Our results explain the cases where LOREs are detected on only one path as resulting from transmitter-receiver geometry significantly which impacts the modal content and therefore the observed VLF recovery time.

  5. Transmittance and Refractive Index of the Lanthanum Strontium Aluminium Tantalum Oxide Crystal

    Institute of Scientific and Technical Information of China (English)

    HU Bo-Qing; WANG Xiao-Ming; ZHOU Tang; ZHAO Zong-Yuan; WU Xing; CHEN Xiao-Long

    2001-01-01

    The lanthanum strontium aluminium tantalum oxide (LSAT) crystal is grown by means of a floating or pulling method. Its optical transmittance, refractive indices in visible and near-infrared areas and its dispersion curve are reported. The transparence range of LSAT is from 0.45 to 4.2μm and its refractive index is 2.0244.

  6. Auxiliary VHF transmitter to aid recovery of solar Argos/GPS PTTs

    Science.gov (United States)

    Christopher P. Hansen; Mark A. Rumble; R. Scott Gamo; Joshua J. Millspaugh

    2014-01-01

    While conducting greater sage-grouse (Centrocercus urophasianus) research, we found that solar-powered global positioning systems platform transmitter terminals (GPS PTTs) can be lost if the solar panel does not receive adequate sunlight. Thus, we developed 5-g (mortality sensor included; Prototype A) and 9.8-g (no mortality sensor; Prototype B) auxiliary very high...

  7. Integrated Inductors for RF Transmitters in CMOS/MEMS Smart Microsensor Systems

    Science.gov (United States)

    Kim, Jong-Wan; Takao, Hidekuni; Sawada, Kazuaki; Ishida, Makoto

    2007-01-01

    This paper presents the integration of an inductor by complementary metal-oxide-semiconductor (CMOS) compatible processes for integrated smart microsensor systems that have been developed to monitor the motion and vital signs of humans in various environments. Integration of radio frequency transmitter (RF) technology with complementary metal-oxide-semiconductor/micro electro mechanical systems (CMOS/MEMS) microsensors is required to realize the wireless smart microsensors system. The essential RF components such as a voltage controlled RF-CMOS oscillator (VCO), spiral inductors for an LC resonator and an integrated antenna have been fabricated and evaluated experimentally. The fabricated RF transmitter and integrated antenna were packaged with subminiature series A (SMA) connectors, respectively. For the impedance (50 Ω) matching, a bonding wire type inductor was developed. In this paper, the design and fabrication of the bonding wire inductor for impedance matching is described. Integrated techniques for the RF transmitter by CMOS compatible processes have been successfully developed. After matching by inserting the bonding wire inductor between the on-chip integrated antenna and the VCO output, the measured emission power at distance of 5 m from RF transmitter was -37 dBm (0.2 μW).

  8. Photonic chip based 1.28 Tbaud transmitter optimization and receiver OTDM demultiplexing

    DEFF Research Database (Denmark)

    Vo, T.D.; Hu, Hao; Galili, Michael

    2010-01-01

    We propose chip-based Tbaud processing for all-optical performance monitoring, switching and demultiplexing. We demonstrate the first transmitter optimization and receiver-end demultiplexing of 1.28 Tbit/s OOK signals. Both exploited Kerr nonlinearity in dispersion-engineered As$_2$S$_3$ planar w...

  9. A combined irradiance-transmittance solar spectrum and its application to photovoltaic efficiency calculations.

    Science.gov (United States)

    Ireland, P J; Wagner, S; Kazmerski, L L; Hulstrom, R L

    1979-05-11

    SOLTRAN is a flexible computer model for the direct solar beam intensity spectrum at the earth's surface. It has been derived by combining the extra-terrestrial solar spectrum with the atmospheric transmittance spectrum. Application of SOLTRAN to the calculation of the potential efficiency of photovoltaic cells demonstrates the effect of atmospheric absorption bands. These bands prevent unequivocal assignment of optimum energy gap values.

  10. Breaking the Transmitter-Receiver Isolation Barrier in Mobile Handsets with Spatial Duplexing

    DEFF Research Database (Denmark)

    Alrabadi, Osama; Tatomirescu, Alexandru; Knudsen, Mikael;

    2013-01-01

    In full-duplex radio communication systems like eUTRAN, CDMA-2000, the radio transmitter (Tx) is active at the same time as the radio receiver (Rx). The Tx and the Rx will be using separate dedicated frequency bands and the Tx-Rx isolation is ensured by duplex filters. However, agile duplexers req...

  11. Multi-transmitter multi-receiver null coupled systems forinductive detection and characterization of metallic objects

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J. Torquil; Morrison, H. Frank; Doolittle, Lawrence R.; Tseng, Hung-Wen

    2005-10-17

    Equivalent dipole polarizabilities are a succinct way tosummarize the inductive response of an isolated conductive body atdistances greater than the scale of the body. Their estimation requiresmeasurement of secondary magnetic fields due to currents induced in thebody by time varying magnetic fields in at least three linearlyindependent (e.g., orthogonal) directions. Secondary fields due to anobject are typically orders of magnitude smaller than the primaryinducing fields near the primary field sources (transmitters). Receivercoils may be oriented orthogonal to primary fields from one or twotransmitters, nulling their response to those fields, but simultaneouslynulling to fields of additional transmitters is problematic. Iftransmitter coils are constructed symmetrically with respect to inversionin a point, their magnetic fields are symmetric with respect to thatpoint. If receiver coils are operated in pairs symmetric with respect toinversion in the same point, then their differenced output is insensitiveto the primary fields of any symmetrically constructed transmitters,allowing nulling to three (or more) transmitters. With a sufficientnumber of receivers pairs, object equivalent dipole polarizabilities canbe estimated in situ from measurements at a single instrument sitting,eliminating effects of inaccurate instrument location on polarizabilityestimates. The method is illustrated with data from a multi-transmittermulti-receiver system with primary field nulling through differencedreceiver pairs, interpreted in terms of principal equivalent dipolepolarizabilities as a function of time.

  12. Light transmittance of fiber posts following various surface treatments: A preliminary study

    Science.gov (United States)

    Cekic-Nagas, Isil; Ergun, Gulfem; Egilmez, Ferhan

    2016-01-01

    Objective: The objective of this study was to compare the light transmittance of fiber posts following application of various surface treatments. Materials and Methods: Fiber post specimens (Snowpost red size #14) were tested (n = 7). The fiber posts were divided into five groups according to the application of surface treatments: Group 1: No surface treatment; Group 2: Etched with hydrofluoric acid (HF) + silane application; Group 3: Airborne-particle abraded with 110 μm Al2O3; Group 4: Irradiated with erbium: Yttrium-aluminum-garnet laser; Group 5: Airborne-particle abraded with 110 μm Al2O3 + silane application. The light transmittance of the specimens was compared using a spectrophotometer. Statistical significance was determined using one-way analysis of variance (ANOVA) (α = 0.05). Results: One-way ANOVA revealed that surface treatment had significant effects on light transmittance of posts (P < 0.001). While laser treatment had the highest percentage of light transmittance, treatment with silane following HF application had the lowest. Conclusion: Application of surface treatments might negatively affect the light transmission property of fiber posts. PMID:27095902

  13. Design considerations on ultra-low-power wireless transmitters for wearable medical devices.

    Science.gov (United States)

    Manstretta, Danilo

    2010-01-01

    A wireless transmitter for wearable bio-sensing applications must fulfill very specialized requirements. It has been estimated that for truly wearable systems it must operate with an average power consumption of less than 140 microW. The alternatives, pitfalls, and realistic performance of robust, low power signal transmission will be addressed.

  14. Joint inversion for transmitter navigation and seafloor resistivity for frequency-domain marine CSEM data

    Science.gov (United States)

    Li, Gang; Li, Yuguo

    2017-01-01

    We present a joint inversion method for the transmitter navigation and the seafloor resistivity for frequency domain marine controlled-source electromagnetic (CSEM) data. The inversion approach is based on the modified BFGS scheme, which has an advantage that one can update the Hessian matrix by using the BFGS scheme rather than computing the Hessian matrix itself during the inversion process. The partial derivatives of the electromagnetic field responses with respect to both the seafloor resistivity and the transmitter navigation parameters including the azimuth, dip and horizontal positions of the transmitter antenna are analytically calculated. We invert for both the navigation parameters of the towed dipole source (including antenna azimuth, dip, and horizontal positions) and seafloor resistivity by using the whole range of data instead of the near-field data (usually source-receiver offset navigation parameters can be independently resolved, and a better reconstruction can be obtained with multiple frequency data. The inversions of both the synthetical and field data sets indicate that our inversion method can simultaneously reconstruct seafloor resistivity structures and transmitter navigation parameters.

  15. Analysis of power efficiencies of polar transmitter and HPA in OFDM communication system

    Science.gov (United States)

    Ryu, Heung-Gyoon

    2014-02-01

    Polar transmitter is known as good candidates for high data rate systems such as OFDM (orthogonal frequency division multiplexing) because they can obtain high-efficiency switched-mode radio frequency (RF) power amplifiers. But it is important to consider the nonlinear effects and power efficiency of the amplifier in the OFDM communication systems. High PAPR (peak-to-average power ratio) causes performance degradation by non-linear distortion in OFDM communication system. So to avoid non-linear distortion, back-off is needed. In addition, output of amplifier is lower and the power efficiency is reduced because of back-off. In this article, we compare PAE (power added efficiency) of polar transmitter in OFDM system and PAE of HPA (high power amplifier) in OFDM system. Also, we analyse PAE according to back-off in DFT-spread OFDM (discrete Fourier transform-spread OFDM), which is PAPR reduction method and we compare with PAE of polar transmitter in OFDM system. And we analyse output spectrum of OFDM and DFT-spread OFDM system. Through spectrum analysis, we analyse PAE of OFDM and DFT-spread OFDM, which is satisfied with output spectrum mask of 3rd generation long term evolution (3G LTE) and also compare with PAE polar transmitter of OFDM system, which is satisfied with spectrum mask. Finally, we analyse PAE according to modulation method and analyse PAE of OFDM and DFT-spread OFDM at same bit error rate.

  16. Far infrared transmittance of Sc2@C84 and Er2@C82

    NARCIS (Netherlands)

    Grannan, S.M.; Birmingham, J.T.; Richards, P.L.; Bethune, D.S.; Vries, M.S. de; Loosdrecht, P.H.M. van; Dorn, H.C.; Burbank, P.; Bailey, J.; Stevenson, S.

    1997-01-01

    We have measured the far infrared transmittance of Sc2@C84 and Er2@C82 at 1.5 K between 30 and 200 cm-1. Both materials are observed to have a large primary absorption feature centered at 95 cm-1 with a width of approximately 50 cm-1, as well as a number of secondary absorption features which are di

  17. 47 CFR 80.169 - Operators required to adjust transmitters or radar.

    Science.gov (United States)

    2010-10-01

    ... radar. 80.169 Section 80.169 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Requirements § 80.169 Operators required to adjust transmitters or radar. (a) All adjustments of radio... transmitting Morse code. (c) Only persons holding an operator certificate containing a ship radar endorsement...

  18. Effect of package light transmittance on the vitamin content of pasteurized whole milk

    NARCIS (Netherlands)

    Soffert, A.; Pieper, G.; Jetten, J.

    2006-01-01

    Pasteurized whole milk (3% fat) was stored under fluorescent light at 8°C in clear 1 litre polyethylene terephthalate (PET) bottles and three variants of pigmented PET bottles with different light transmittance. Changes in the vitamin content were monitored over a period of 10 days. Milk packed in p

  19. Effects of rhynchophylline on monoamine transmitters of striatum and hippocampus in cerebral ischemic rats

    Institute of Scientific and Technical Information of China (English)

    LUYuan-Fu; XIEXiao-Long; WUQin; WENGuo-Rong; YANGSu-Fen; SHIJing-Shan

    2004-01-01

    AIM To investigate the effects of rhynchophylline ( Rhy on monoamine transmitters and its metabolites in striatum and hippocampus of cerebral ischemic rats. METItODS The cerebral ischemic injury of rat was induced by middle cerebral artery occlusion (MCAO). The extracellular fluid of striatum and hippocampus in cerebral ischemic rats was collected by using

  20. Influence of surface light scattering in hydrophobic acrylic intraocular lenses on laser beam transmittance.

    Science.gov (United States)

    Shiraya, Tomoyasu; Kato, Satoshi; Minami, Keiichiro; Miyata, Kazunori

    2017-02-01

    The aim of this study was to experimentally examine the changes in the transmittances of photocoagulation lasers when surface light scattering increases in AcrySof intraocular lenses (IOLs). SA60AT IOLs (Alcon) were acceleratingly aging for 0, 3, 5, and 10 years to simulate surface light scattering, and the surface light-scattering intensities of both IOL surfaces were measured using a Scheimpflug photographer. The powers of laser beams that passed from a laser photocoagulator through the aged IOLs were measured at 532, 577, and 647 nm. Changes in the laser power and transmittance with the years of aging and the intensities of surface light scattering were examined. Although the intensity of surface light scattering increased with the years of aging, the laser power did not change with the years of aging (P > 0.30, Kruskal-Wallis test). There were no significant changes in the laser transmittance with the years of aging or the laser wavelength (P > 0.30 and 0.57, respectively). The intensity of surface light scattering revealed no significant association with the laser transmittance at any wavelength (P > 0.37, liner regression). The increases in the surface light scattering of the AcrySof IOLs would not influence retinal photocoagulation treatments for up to 10 years after implantation.

  1. Linear thermal transmittance of the assembly of the glazing and the frame in windows

    DEFF Research Database (Denmark)

    Svendsen, Svend; Laustsen, Jacob Birck; Kragh, Jesper

    2005-01-01

    The thermal transmittance or U-value of windows can be found by calculation according to the standards EN ISO 10077-1/2 (CEN,2000). The window U-value is calculated from the U-value of the glazing and the frame as well as the linear thermal transmittance of the assembly of the glazing and the frame....... The U-value of the glazing and the frame can be calculated separately while the calculation of the linear thermal transmittance includes the design of the edge construction of the glazing unit but also the design of the frame and the glazing unit. The edge construction of glazing units is made up...... by use of an equivalent thermal conductivity of a box of a fictive material that replaces the detailed spacer profile. A number of typical spacer profile products have been used in a test of the methodology where the linear thermal transmittance of the assembly of the glazing and the frame was calculated...

  2. Evaluation on Uncertainty of Measurement Result of Pressure Transmitter Field Verification

    Institute of Scientific and Technical Information of China (English)

    CHEN; Ping

    2015-01-01

    Calibration data of pressure instrument,pressure transmitter and pressure measurement control system with field pressure calibrator on the site of production and work can represent actual situation of the production and work,reduce and avoid the error on account of the difference of

  3. Measurement of the total solar energy transmittance (g-value) for conventional glazings

    DEFF Research Database (Denmark)

    Duer, Karsten

    1998-01-01

    Three different glazings have been investigated in the Danish experimental setup METSET. (A device for calorimetric measurement of total solar energy transmittance - g-value).The purpose of the measurements is to increase the confidence in the calorimetric measurements. This is done by comparison...

  4. A small long-life acoustic transmitter for studying the behavior of aquatic animals

    Energy Technology Data Exchange (ETDEWEB)

    Lu, J. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Deng, Z. D. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Li, H. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Myjak, M. J. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Martinez, J. J. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Xiao, J. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Brown, R. S. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA; Cartmell, S. S. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99332, USA

    2016-11-01

    The lack of stronger acoustic signal, longer service life and smaller size from off-the-shelf transmitters has precluded intensive research for environmental monitoring of certain species using acoustic telemetry techniques. In this study we developed a small long-life acoustic transmitter with the length of approximately 24.2 mm, the diameter of approximately 5.0 mm, and the dry weight of approximately 0.72 g. The new transmitter can generate an acoustic signal at selectable source level between 159 and 163 dB re 1 µPa at 1 m. The new acoustic transmitter has an operation lifetime up to a year or longer at a pulse rate interval of 15 seconds, and also has a signal detection range up to at least 500 meters that enhances detection probability in a quiet environment. The new technology makes long-term acoustic telemetry studies of small fish possible and is being deployed for long-term tracking of juvenile sturgeon.

  5. Enhanced quantal release of excitatory transmitter in anterior cingulate cortex of adult mice with chronic pain

    Directory of Open Access Journals (Sweden)

    Zhao Ming-Gao

    2009-01-01

    Full Text Available Abstract The anterior cingulate cortex (ACC is a forebrain structure that plays important roles in emotion, learning, memory and persistent pain. Our previous studies have demonstrated that the enhancement of excitatory synaptic transmission was induced by peripheral inflammation and nerve injury in ACC synapses. However, little information is available on their presynaptic mechanisms, since the source of the enhanced synaptic transmission could include the enhanced probability of neurotransmitter release at existing release sites and/or increases in the number of available vesicles. The present study aims to perform quantal analysis of excitatory synapses in the ACC with chronic pain to examine the source of these increases. The quantal analysis revealed that both probability of transmitter release and number of available vesicles were increased in a mouse model of peripheral inflammation, whereas only probability of transmitter release but not number of available vesicles was enhanced in a mouse model of neuropathic pain. In addition, we compared the miniature excitatory postsynaptic potentials (mEPSCs in ACC synapses with those in other pain-related brain areas such as the amygdala and spinal cord. Interestingly, the rate and amplitude of mEPSCs in ACC synapses were significantly lower than those in the amygdala and spinal cord. Our studies provide strong evidences that chronic inflammatory pain increases both probability of transmitter release and number of available vesicles, whereas neuropathic pain increases only probability of transmitter release in the ACC synapses.

  6. Effect of package light transmittance on the vitamin content of pasteurized whole milk

    NARCIS (Netherlands)

    Soffert, A.; Pieper, G.; Jetten, J.

    2006-01-01

    Pasteurized whole milk (3% fat) was stored under fluorescent light at 8°C in clear 1 litre polyethylene terephthalate (PET) bottles and three variants of pigmented PET bottles with different light transmittance. Changes in the vitamin content were monitored over a period of 10 days. Milk packed in

  7. Throughput Optimal Policies for Energy Harvesting Wireless Transmitters with Non-Ideal Circuit Power

    CERN Document Server

    Xu, Jie

    2012-01-01

    Characterizing the fundamental tradeoffs for maximizing energy efficiency (EE) versus spectrum efficiency (SE) is a key problem in wireless communication. In this paper, we address this problem for a point-to-point additive white Gaussian noise (AWGN) channel with the transmitter powered solely via energy harvesting from the environment. In addition, we assume a practical on-off transmitter model with non-ideal circuit power, i.e., when the transmitter is on, its consumed power is the sum of the transmit power and a constant circuit power. Under this setup, we study the optimal transmit power allocation to maximize the average throughput over a finite horizon, subject to the time-varying energy constraint and the non-ideal circuit power consumption. First, we consider the off-line optimization under the assumption that the energy arrival time and amount are a priori known at the transmitter. Although this problem is non-convex due to the non-ideal circuit power, we show an efficient optimal solution that in g...

  8. Spatial integration of local transmitter responses in motoneurones of the turtle spinal cord in vitro

    DEFF Research Database (Denmark)

    Skydsgaard, Morten Arnika; Hounsgaard, J

    1994-01-01

    1. Integration of responses to local activation of transmitter receptors in the dendrites of motoneurones was investigated in a slice preparation of the turtle spinal cord. Membrane-active substances were applied from up to three independent iontophoresis electrodes during intracellular recording...

  9. Validation of temperature-sensitive radio transmitters for measurement of body temperature in small animals

    NARCIS (Netherlands)

    Williams, Joseph B.; Tieleman, B. I.; Shobrak, Mohammed

    2009-01-01

    As part of a study on the core body temperature (T(b)) of desert birds, we purposed to use temperature-sensitive implantable radio transmitters. Because of the difficulty in recapturing these birds, we needed to know if these electronic devices held their calibration over the duration of normal batt

  10. A novel Chirped Return-to-Zero Transmitter and Transmission Experiments

    DEFF Research Database (Denmark)

    Liu, Fenghai; Peucheret, Christophe; Xueyan, Zheng

    2000-01-01

    A new 10 Gb/s chirped return-to-zero transmitter using CW light modulated by only one external modulator is proposed. Transmission over 3600 km of standard single mode fibre is performed in a re-circulating loop set-up with 80 km amplifier span....

  11. Self-shielding printed circuit boards for high frequency amplifiers and transmitters

    Science.gov (United States)

    Galvin, D.

    1969-01-01

    Printed circuit boards retaining as much copper as possible provide electromagnetic shielding between stages of the high frequency amplifiers and transmitters. Oscillation is prevented, spurious output signals are reduced, and multiple stages are kept isolated from each other, both thermally and electrically.

  12. 47 CFR 61.38 - Supporting information to be submitted with letters of transmittal.

    Science.gov (United States)

    2010-10-01

    ... letters of transmittal. 61.38 Section 61.38 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... explanation of the changed or new matter, the reasons for the filing, the basis of ratemaking employed, and...) of this section, the filing carrier must submit all additional cost, marketing and other...

  13. 22 CFR 124.12 - Required information in letters of transmittal.

    Science.gov (United States)

    2010-04-01

    ... AGREEMENTS, OFF-SHORE PROCUREMENT AND OTHER DEFENSE SERVICES § 124.12 Required information in letters of transmittal. (a) An application for the approval of a manufacturing license or technical assistance agreement... scope of the agreement. (3) A statement identifying the U.S. Government contract under which the...

  14. High-power multi-beam diode laser transmitter for a flash imaging lidar

    Science.gov (United States)

    Holmlund, Christer; Aitta, Petteri; Kivi, Sini; Mitikka, Risto; Tyni, Lauri; Heikkinen, Veli

    2013-10-01

    VTT Technical Research Centre of Finland is developing the transmitter for the "Flash Optical Sensor for TErrain Relative NAVigation" (FOSTERNAV) multi-beam flash imaging lidar. FOSTERNAV is a concept demonstrator for new guidance, navigation and control (GNC) technologies to fulfil the requirements for landing and docking of spacecraft as well as for navigation of rovers. This paper presents the design, realisation and testing of the multi-beam continuous-wave (CW) laser transmitter to be used in a 256x256 pixel flash imaging lidar. Depending on the target distance, the lidar has three operation modes using either several beams with low divergence or one single beam with a large divergence. This paper describes the transmitter part of the flash imaging lidar with focus on the electronics and especially the laser diode drivers. The transmitter contains eight fibre coupled commercial diode laser modules with a total peak optical power of 32 W at 808 nm. The main requirement for the laser diode drivers was linear modulation up to a frequency of 20 MHz allowing, for example, low distortion chirps or pseudorandom binary sequences. The laser modules contain the laser diode, a monitoring photodiode, a thermo-electric cooler, and a thermistor. The modules, designed for non-modulated and low-frequency operation, set challenging demands on the design of the drivers. Measurement results are presented on frequency response, and eye diagrams for pseudo-random binary sequences.

  15. The application of the photoacoustic transmittance oscillations for determining elastic constants in gallium and indium selenides

    Science.gov (United States)

    Ferrer, Ch.; Segura, A.; Andrés, M. V.; Muñoz, V.; Pellicer, J.

    1996-03-01

    Transmittance periodic oscillations are observed in GaSe and InSe on excitation with optical pulses. Such oscillations are explained in terms of photoacoustic generation of dilatational waves, which become resonant within the crystal. Spectral analysis of those oscillations in samples of different thickness has led to an accurate determination of the longitudinal acoustic-wave velocity along the crystallographic axis c.

  16. 78 FR 57253 - Airworthiness Directives; Honeywell ASCa Inc. Emergency Locator Transmitters Installed on Various...

    Science.gov (United States)

    2013-09-18

    ... general visual inspections of the ELT transmitter units (TUs), and corrective actions if necessary. This... combustion in the area of the ELT TU. We are issuing this AD to detect and correct discrepancies of the... Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call...

  17. Reading Rooms of Russian Province in 1920s as Transmitters of Soviet Values

    Directory of Open Access Journals (Sweden)

    Vadim P. Nikolashin

    2014-12-01

    Full Text Available The article features regional aspects of reading room activities in the 1920s as transmitters of Soviet values. Authors analyze forms and methods of work of this type of socio-cultural institutions, study specifics of relationship of countrymen. The conducted analysis allows speaking about positive impact by reading rooms on evolution of a country life.

  18. Adaptive Transmitter Optimization in Multiuser Multiantenna Systems: Theoretical Limits, Effect of Delays, and Performance Enhancements

    Directory of Open Access Journals (Sweden)

    Samardzija Dragan

    2005-01-01

    Full Text Available The advances in programmable and reconfigurable radios have rendered feasible transmitter optimization schemes that can greatly improve the performance of multiple-antenna multiuser systems. Reconfigurable radio platforms are particularly suitable for implementation of transmitter optimization at the base station. We consider the downlink of a wireless system with multiple transmit antennas at the base station and a number of mobile terminals (i.e., users each with a single receive antenna. Under an average transmit power constraint, we consider the maximum achievable sum data rates in the case of (1 zero-forcing (ZF spatial prefilter, (2 modified zero-forcing (MZF spatial prefilter, and (3 triangularization spatial prefilter coupled with dirty-paper coding (DPC transmission scheme. We show that the triangularization with DPC approaches the closed-loop MIMO rates (upper bound for higher SNRs. Further, the MZF solution performs very well for lower SNRs, while for higher SNRs, the rates for the ZF solution converge to the MZF rates. An important impediment that degrades the performance of such transmitter optimization schemes is the delay in channel state information (CSI. We characterize the fundamental limits of performance in the presence of delayed CSI and then propose performance enhancements using a linear MMSE predictor of the CSI that can be used in conjunction with transmitter optimization in multiple-antenna multiuser systems.

  19. Design of an Omnidirectional Multibeam Transmitter for High-Speed Indoor Wireless Communications

    Directory of Open Access Journals (Sweden)

    Jaw-Luen Tang

    2010-01-01

    Full Text Available For future high speed indoor wireless communication, diffuse wireless optical communications offer more robust optical links against shadowing than line-of-sight links. However, their performance may be degraded by multipath dispersion arising from surface reflections. We have developed a multipath diffusive propagation model capable of providing channel impulse responses data. It is aimed to design and simulate any multibeam transmitter under a variety of indoor environments. In this paper, a multi-beam transmitter system associated with hemisphere structure is proposed to fight against the diverse effects of multipath distortion albeit, at the cost of increased laser power and cost. Simulation results of multiple impulse responses showed that this type of multi-beam transmitter can significantly improve the performance of BER suitable for high bit rate application. We present the performance and simulation results for both line-of-sight and diffuse link configurations. We propose a design of power radiation pattern for a transmitter in achieving uniform and full coverage of power distributions for diffuse indoor optical wireless systems.

  20. Experimental demonstration of a scalable transmitter frontend technique in IMDD-OFDMA-PON upstream scheme

    Science.gov (United States)

    Ju, Cheng; Liu, Na; Wang, Dongdong; Zhang, Zhiguo; Chen, Xue

    2016-11-01

    Scalable transmitter frontend scheme is proposed to reduce the sampling rate of digital-to-analog converter (DAC) and the complexity of digital signal processing (DSP) in intensity modulation and direct detection (IMDD) OFDMA-PON upstream scenarios. The hardware cost of each ONU is substantially decreased. The feasibility of the proposed scheme is experimentally demonstrated.

  1. Performance Assessment of Bi-Directional Knotless Tissue-Closure Device in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters, 2010 - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, Christa M.; Bryson, Amanda J.; Carpenter, Scott M.; Knox, Kasey M.; Gay, Marybeth E.; Wagner, Katie A.

    2012-09-10

    In 2010, researchers at Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) conducted a compliance monitoring study—the Lower Columbia River Acoustic Transmitter Investigations of Dam Passage Survival and Associated Metrics 2010 (Carlson et al. in preparation)—for the U.S. Army Corps of Engineers (USACE), Portland District. The purpose of the compliance study was to evaluate juvenile Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) passage routes and survival through the lower three Columbia River hydroelectric facilities as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp; NOAA Fisheries 2008) and the Columbia Basin Fish Accords (Fish Accords; 3 Treaty Tribes and Action Agencies 2008).

  2. A new topology and control method for electromagnetic transmitter power supplies

    Science.gov (United States)

    Zhang, Yiming; Zhang, Jialin; Yuan, Dakang

    2017-04-01

    As essential equipment for electromagnetic exploration, electromagnetic transmitter reverse the steady power supply with desired frequency and transmit the power through grounding electrodes. To obtain effective geophysical data during deep exploration, the transmitter needs to be high-voltage, high-current, with high-accuracy output, and yet compact and light. The researches on the power supply technologies for high-voltage high-power electromagnetic transmitter is of significant importance to the deep geophysical explorations. Therefore, the performance of electromagnetic transmitter is mainly subject to the following two aspects: the performance of emission current and voltage, and the power density. These requirements bring technical difficulties to the development of power supplies. Conventionally, high-frequency switching power supplies are applied in the design of a high-power transmitter power supply. However, the structure of the topology is complicate, which may reduce the controllability of the output voltage and the reliability of the system. Without power factor control, the power factor of the structure is relatively low. Moreover high switching frequency causes high loss. With the development of the PWM (pulse width modulation) technique, its merits of simple structure, low loss, convenient control and unit power factor have made it popular in electrical energy feedback, active filter, and power factor compensation. Studies have shown that using PWM converters and space vector modulation have become the trend in designing transmitter power supply. However, the earth load exhibits different impedances at different frequencies. Thus ensuing high-accuracy and a stable output from a transmitter power supply in harsh environment has become a key topic in the design of geophysical exploration instruments. Based on SVPWM technology, an electromagnetic transmitter power supply has been designed and its control strategy has been studied. The transmitting

  3. Comparing the survival rate of juvenile Chinook salmon migrating through hydropower systems using injectable and surgical acoustic transmitters

    Science.gov (United States)

    Deng, Z. D.; Martinez, J. J.; Li, H.; Harnish, R. A.; Woodley, C. M.; Hughes, J. A.; Li, X.; Fu, T.; Lu, J.; McMichael, G. A.; Weiland, M. A.; Eppard, M. B.; Skalski, J. R.; Townsend, R. L.

    2017-01-01

    Acoustic telemetry is one of the primary technologies for studying the behavior and survival of fishes throughout the world. The size and performance of the transmitter are key limiting factors. The newly developed injectable transmitter is the first acoustic transmitter that can be implanted via injection instead of surgery. A two-part field study was conducted to evaluate the performance of the injectable transmitter and its effect on the survival of implanted fish. The injectable transmitter performed well and similarly to the proceeding generation of commercially-available JSATS transmitters tested concurrently. Snake River subyearling Chinook salmon smolts implanted with the injectable transmitter had a higher survival probability from release to each of eleven downstream detection arrays, because reach-specific survival estimates were significantly higher for the injectable group in three of the eleven reaches examined. Overall, the injectable group had a 0.263 (SE = 0.017) survival probability over the entire 500 km study area compared to 0.199 (0.012) for the surgically implanted group. The reduction in size and ability to implant the new transmitter via injection has reduced the tag or tagging effect bias associated with studying small fishes. The information gathered with this new technology is helping to evaluate the impacts of dams on fishes. PMID:28220850

  4. Comparing the survival rate of juvenile Chinook salmon migrating through hydropower systems using injectable and surgical acoustic transmitters.

    Science.gov (United States)

    Deng, Z D; Martinez, J J; Li, H; Harnish, R A; Woodley, C M; Hughes, J A; Li, X; Fu, T; Lu, J; McMichael, G A; Weiland, M A; Eppard, M B; Skalski, J R; Townsend, R L

    2017-02-21

    Acoustic telemetry is one of the primary technologies for studying the behavior and survival of fishes throughout the world. The size and performance of the transmitter are key limiting factors. The newly developed injectable transmitter is the first acoustic transmitter that can be implanted via injection instead of surgery. A two-part field study was conducted to evaluate the performance of the injectable transmitter and its effect on the survival of implanted fish. The injectable transmitter performed well and similarly to the proceeding generation of commercially-available JSATS transmitters tested concurrently. Snake River subyearling Chinook salmon smolts implanted with the injectable transmitter had a higher survival probability from release to each of eleven downstream detection arrays, because reach-specific survival estimates were significantly higher for the injectable group in three of the eleven reaches examined. Overall, the injectable group had a 0.263 (SE = 0.017) survival probability over the entire 500 km study area compared to 0.199 (0.012) for the surgically implanted group. The reduction in size and ability to implant the new transmitter via injection has reduced the tag or tagging effect bias associated with studying small fishes. The information gathered with this new technology is helping to evaluate the impacts of dams on fishes.

  5. Comparing the survival rate of juvenile Chinook salmon migrating through hydropower systems using injectable and surgical acoustic transmitters

    Science.gov (United States)

    Deng, Z. D.; Martinez, J. J.; Li, H.; Harnish, R. A.; Woodley, C. M.; Hughes, J. A.; Li, X.; Fu, T.; Lu, J.; McMichael, G. A.; Weiland, M. A.; Eppard, M. B.; Skalski, J. R.; Townsend, R. L.

    2017-02-01

    Acoustic telemetry is one of the primary technologies for studying the behavior and survival of fishes throughout the world. The size and performance of the transmitter are key limiting factors. The newly developed injectable transmitter is the first acoustic transmitter that can be implanted via injection instead of surgery. A two-part field study was conducted to evaluate the performance of the injectable transmitter and its effect on the survival of implanted fish. The injectable transmitter performed well and similarly to the proceeding generation of commercially-available JSATS transmitters tested concurrently. Snake River subyearling Chinook salmon smolts implanted with the injectable transmitter had a higher survival probability from release to each of eleven downstream detection arrays, because reach-specific survival estimates were significantly higher for the injectable group in three of the eleven reaches examined. Overall, the injectable group had a 0.263 (SE = 0.017) survival probability over the entire 500 km study area compared to 0.199 (0.012) for the surgically implanted group. The reduction in size and ability to implant the new transmitter via injection has reduced the tag or tagging effect bias associated with studying small fishes. The information gathered with this new technology is helping to evaluate the impacts of dams on fishes.

  6. Pancreatic beta cells synthesize neuropeptide Y and can rapidly release peptide co-transmitters.

    Directory of Open Access Journals (Sweden)

    Matthew D Whim

    Full Text Available BACKGROUND: In addition to polypeptide hormones, pancreatic endocrine cells synthesize a variety of bioactive molecules including classical transmitters and neuropeptides. While these co-transmitters are thought to play a role in regulating hormone release little is known about how their secretion is regulated. Here I investigate the synthesis and release of neuropeptide Y from pancreatic beta cells. METHODOLOGY/PRINCIPAL FINDINGS: NPY appears to be an authentic co-transmitter in neonatal, but not adult, beta cells because (1 early in mouse post-natal development, many beta cells are NPY-immunoreactive whereas no staining is observed in beta cells from NPY knockout mice; (2 GFP-expressing islet cells from an NPY(GFP transgenic mouse are insulin-ir; (3 single cell RT-PCR experiments confirm that the NPY(GFP cells contain insulin mRNA, a marker of beta cells. The NPY-immunoreactivity previously reported in alpha and delta cells is therefore likely to be due to the presence of NPY-related peptides. INS-1 cells, a beta cell line, are also NPY-ir and contain NPY mRNA. Using the FMRFamide tagging technique, NPY secretion was monitored from INS-1 beta cells with high temporal resolution. Peptide release was evoked by brief depolarizations and was potentiated by activators of adenylate cyclase and protein kinase A. Following a transient depolarization, NPY-containing dense core granules fused with the cell membrane and discharged their contents within a few milliseconds. CONCLUSIONS: These results indicate that after birth, NPY expression in pancreatic islets is restricted to neonatal beta cells. The presence of NPY suggests that peptide co-transmitters could mediate rapid paracrine or autocrine signaling within the endocrine pancreas. The FMRFamide tagging technique may be useful in studying the release of other putative islet co-transmitters in real time.

  7. Comparing effects of transmitters within and among populations: application to swimming performance of juvenile Chinook salmon

    Science.gov (United States)

    Perry, Russell W.; Plumb, John M.; Fielding, Scott D.; Adams, Noah S.; Rondorf, Dennis W.

    2013-01-01

    The sensitivity of fish to a transmitter depends on factors such as environmental conditions, fish morphology, life stage, rearing history, and tag design. However, synthesizing general trends across studies is difficult because each study focuses on a particular performance measure, species, life stage, and transmitter model. These differences motivated us to develop simple metrics that allow effects of transmitters to be compared among different species, populations, or studies. First, we describe how multiple regression analysis can be used to quantify the effect of tag burden (transmitter mass relative to fish mass) on measures of physiological performance. Next, we illustrate how the slope and intercept parameters can be used to calculate two summary statistics: θ, which estimates the tag burden threshold above which the performance of tagged fish begins to decline relative to untagged fish; and k, which measures the percentage change in performance per percentage point increase in tag burden. When θ = 0, k provides a single measure of the tag's effect that can be compared among species, populations, or studies. We apply this analysis to two different experiments that measure the critical swimming speed (U crit) of tagged juvenile Chinook Salmon Oncorhynchus tshawytscha. In both experiments, U crit declined as tag burden increased, but we found no significant threshold in swimming performance. Estimates of θ ranged from −0.6% to 2.1% among six unique treatment groups, indicating that swimming performance began to decline at a relatively low tag burden. Estimates of k revealed that U crit of tagged fish declined by −2.68% to −4.86% for each 1% increase in tag burden. Both θ and k varied with the tag's antenna configuration, tag implantation method, and posttagging recovery time. Our analytical approach can be used to gain insights across populations to better understand factors affecting the ability of fish to carry a transmitter.

  8. Photon tunneling and transmittance resonance through a multi-layer structure with a left-handed material

    Institute of Scientific and Technical Information of China (English)

    He Ying; Zhang Xia; Yang Yan-Fang; Li Chun-Fang

    2011-01-01

    This paper investigates the photon tunneling and transmittance resonance through a multi-layer structure including a left-handed material(LHM). An analytical expression for the transmittance in a five-layer structure is given by the analytical transfer matrix method. The transmittance is studied as a function of the refractive index and the width of the LHM layer. The perfect photon tunneling results from the multi-layer structure, especially from the relation between the magnitude of the refractive index and the width of the LHM layer and those of the adjoining layers.Photons may tunnel through a much greater distance in this structure. Transmittance resonance happens, the peaks and valleys appear periodically at the resonance thickness. For an LHM with inherent losses, the perfect transmittance is suppressed.

  9. Optimum light transmittance for seed germination and early seedling recruitment of Pinus koraiensis: implications for natural regeneration

    Directory of Open Access Journals (Sweden)

    Zhang M

    2015-12-01

    Full Text Available Light transmittance regulated by canopy openness influences the microsite conditions for natural regeneration. The successful transition from seed germination to subsequent seedling recruitment (i.e., early seedling survival and growth determines the natural regeneration potential. However, there is little information on the effect of varying light transmittance on seed germination and seedling recruitment of Pinus koraiensis Siebold & Zucc. (Korean pine. We aimed to determine the optimum light requirements for this transition process in P. koraiensis to propose practical measures for improving its natural regeneration. The transition process was studied under five light transmittance regimes (100%, 60%, 30%, 15% and 5% of full light over two consecutive years (2010 and 2011. The highest germination percentage in both years occurred at 30% light transmittance. Generally, mean germination time (MGT declined with increased light transmittance. Seedling survival exhibited no significant differences between treatments for 1-year-old seedlings, but was higher at 30% than at 5% light transmittance for the 2-year-old seedlings. In contrast, seedling height, root collar diameter and total biomass were highest at 60%-100% light transmittance for both 1- and 2-year-old seedlings. Furthermore, the light transmittance also influenced the growth characteristics of P. koraiensis seedlings through regulating MGT. These results suggest that growth of P. koraiensis seedling requires a higher light transmittance (60%-100% than that required for seed germination, even though 30% light transmittance was favorable to the earlier emergence with larger specific leaf area. Silvicultural measures such as thinning are recommended to increase light irradiance in the forest understorey with the aim of improving the natural regeneration of P. koraiensis.

  10. Laser Atmospheric Transmitter Receiver-Network (LAnTeRN): A new approach for active measurement of atmospheric greenhouse gases

    Science.gov (United States)

    Dobler, J. T.; Braun, M.; Zaccheo, T.

    2012-12-01

    The Laser Atmospheric Transmitter Receiver-Network (LAnTeRN) is a new measurement concept that will enable local, regional and continental determination of key greenhouse gases, with unparalleled accuracy and precision. This new approach will offer the ability to make low bias, high precision, quasi-continuous, measurements to the accuracies required for separating anthropogenic and biogenic sources and sinks. In 2004 ITT Exelis developed an airborne demonstration unit, based on an intensity modulated continuous wave (IM-CW) lidar approach, for actively measuring atmospheric CO2 and O2. The multi-functional fiber laser lidar (MFLL) system relies on low peak power, high reliability, and efficient telecom laser components to implement this unique measurement approach. While evaluating methods for discriminating against thin clouds for the MFLL instrument, a new measurement concept was conceived. LAnTeRN has several fundamental characteristics in common with the MFLL instrument, but is a fundamentally different implementation and capability. The key difference is that LAnTeRN operates in transmission rather than in the traditional backscatter lidar configuration, which has several distinct advantages. Operating as a forward scatter, bistatic lidar system, LAnTeRN enables consideration of continuous monitoring from a geostationary orbit to multiple locations on the ground. Having the receivers on the ground significantly lowers cost and risk compared to an all space based mission, and allows the transmitter subsystem to be implemented, near term, as a hosted payload. Furthermore, the LAnTeRN measurement approach is also applicable for ground to ground measurements where high precision measurements over a long open path is required, such as facilities monitoring, or monitoring of passive volcanoes and fault lines. Using narrow linewidth laser sources allows flexibility to select the position on the absorption feature being probed. This feature allows for weighting the

  11. Ouellette Thermal Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Thermal Test Facility is a joint Army/Navy state-of-the-art facility (8,100 ft2) that was designed to:Evaluate and characterize the effect of flame and thermal...

  12. Cold Vacuum Drying Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Located near the K-Basins (see K-Basins link) in Hanford's 100 Area is a facility called the Cold Vacuum Drying Facility (CVDF).Between 2000 and 2004, workers at the...

  13. Dialysis Facility Compare

    Data.gov (United States)

    U.S. Department of Health & Human Services — Dialysis Facility Compare helps you find detailed information about Medicare-certified dialysis facilities. You can compare the services and the quality of care that...

  14. Explosive Components Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 98,000 square foot Explosive Components Facility (ECF) is a state-of-the-art facility that provides a full-range of chemical, material, and performance analysis...

  15. Materiel Evaluation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — CRREL's Materiel Evaluation Facility (MEF) is a large cold-room facility that can be set up at temperatures ranging from −20°F to 120°F with a temperature change...

  16. Armament Technology Facility (ATF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Armament Technology Facility is a 52,000 square foot, secure and environmentally-safe, integrated small arms and cannon caliber design and evaluation facility....

  17. Integrated Disposal Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Located near the center of the 586-square-mile Hanford Site is the Integrated Disposal Facility, also known as the IDF.This facility is a landfill similar in concept...

  18. Facilities for US Radioastronomy.

    Science.gov (United States)

    Thaddeus, Patrick

    1982-01-01

    Discusses major developments in radioastronomy since 1945. Topics include proposed facilities, very-long-baseline interferometric array, millimeter-wave telescope, submillimeter-wave telescope, and funding for radioastronomy facilities and projects. (JN)

  19. Wastewater Treatment Facilities

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Individual permits for municipal, industrial, and semi-public wastewater treatment facilities in Iowa for the National Pollutant Discharge Elimination System (NPDES)...

  20. Facility Response Plan (FRP)

    Data.gov (United States)

    U.S. Environmental Protection Agency — A Facility Response Plan (FRP) demonstrates a facility's preparedness to respond to a worst case oil discharge. Under the Clean Water Act, as amended by the Oil...

  1. Financing Professional Sports Facilities

    OpenAIRE

    Baade, Robert A.; Victor A. Matheson

    2011-01-01

    This paper examines public financing of professional sports facilities with a focus on both early and recent developments in taxpayer subsidization of spectator sports. The paper explores both the magnitude and the sources of public funding for professional sports facilities.

  2. FDA Certified Mammography Facilities

    Science.gov (United States)

    ... Program Consumer Information (MQSA) Search for a Certified Facility Share Tweet Linkedin Pin it More sharing options ... Email Print This list of FDA Certified Mammography Facilities is updated weekly. If you click on Search ...

  3. Energetics Conditioning Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Energetics Conditioning Facility is used for long term and short term aging studies of energetic materials. The facility has 10 conditioning chambers of which 2...

  4. Energetics Conditioning Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Energetics Conditioning Facility is used for long term and short term aging studies of energetic materials. The facility has 10 conditioning chambers of which 2...

  5. Environmental Toxicology Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Fully-equipped facilities for environmental toxicology researchThe Environmental Toxicology Research Facility (ETRF) located in Vicksburg, MS provides over 8,200 ft...

  6. Ouellette Thermal Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Thermal Test Facility is a joint Army/Navy state-of-the-art facility (8,100 ft2) that was designed to: Evaluate and characterize the effect of flame and thermal...

  7. Projectile Demilitarization Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Projectile Wash Out Facility is US Army Ammunition Peculiar Equipment (APE 1300). It is a pilot scale wash out facility that uses high pressure water and steam...

  8. Low-Cost Facile Fabrication of Flexible Transparent Copper Electrodes by Nanosecond Laser Ablation

    KAUST Repository

    Paeng, Dongwoo

    2015-03-27

    © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Low-cost Cu flexible transparent conducting electrodes (FTCEs) are fabricated by facile nanosecond laser ablation. The fabricated Cu FTCEs show excellent opto-electrical properties (transmittance: 83%, sheet resistance: 17.48 Ω sq-1) with outstanding mechanical durability. Successful demonstration of a touch-screen panel confirms the potential applicability of Cu FTCEs to the flexible optoelectronic devices.

  9. Pressurized burner test facility

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, D.J.; Norton, T.S.; Hadley, M.A. [Morgantown Energy Technology Center, WV (United States)

    1993-06-01

    The Morgantown Energy Technology Center (METC) is currently fabricating a high-pressure burner test facility. The facility was designed to support the development of gas turbine combustion systems fired on natural gas and coal-derived gaseous fuels containing fuel-bound nitrogen. Upon completion of fabrication and shake-down testing in October 1993, the facility will be available for use by industrial and university partners through Cooperative Research and Development Agreements (CRADAs) or through other cooperative arrangements. This paper describes the burner test facility and associated operating parameter ranges and informs interested parties of the availability of the facility.

  10. Evaluation of transmitter attachment techniques on growth of wild turkey poults

    Science.gov (United States)

    Hubbard, M.W.; Tsao, L.-L.C.; Klaas, E.E.; Kaiser, M.; Jackson, D.H.

    1998-01-01

    We compared the effects on growth of backpack-mounted and surgically implanted radiotransmitters used as marking techniques in studies of wild turkey (Meleagris gallopavo) poult survival. We applied repeated-measures analysis of variance (ANOVA) and Bayesian analysis to evaluate the null hypothesis that marking technique did not affect growth. Growth in body mass was similar among treatment groups. We did, however, find differences in wing-growth rates among treatment groups. The control group had the highest wing-growth rate, the backpack group had the lowest growth rate, and the surgical implant group was intermediate. Latex backpack harnesses also caused physical developmental problems that would have negatively biased wild poult survival estimates in the field. Surgically implanted transmitters affected wing growth less than the backpack harnesses and are therefore recommended for attaching transmitters to wild turkey poults.

  11. A novel synthesis approach for birefringent filters having arbitrarily amplitude transmittances

    Science.gov (United States)

    Halassi, Abde Rezzaq; Hamdi, Rachid; Bendimerad, Djalal Falih; Benkelfat, Badr-Eddine

    2016-06-01

    In this paper, we present a novel procedure for the synthesis of a filter having an arbitrarily specified amplitude transmittance. The filter configuration consists of N birefringent stages placed between a polarizer and an analyzer, with each stage containing an identical section and a variable section. An additional variable section is placed in front of the analyzer. The synthesis procedure is based on the resolution of a generalized nonlinear equation system directly deducted from the Jones matrix formalism to determine the angles of each stage, the angle of the analyzer and the phase shifts of the variable sections. A typical example of a 6-stage birefringent filter having an arbitrarily non-symmetric amplitude transmittance is shown and the opto-geometrical parameters are given to demonstrate the efficiency of the proposed synthesis procedure. The results obtained show an excellent agreement with those developed in the literature.

  12. [Visible transmittance techniques for rapid analysis of sugar content of fresh navel orange juices].

    Science.gov (United States)

    Liu, Yan-de; Luo, Ji; Ouyang, Ai-guo

    2007-03-01

    The feasibility of visible spectroscopic technology for rapid quantifying sugar content (SC) of navel orange fresh juices was investigated by means of spectral transmittance technique. A total of 55 juice samples were used to develop the calibration and prediction models. Calibration models based on different spectral ranges and different spectral pretreatment were compared in the precent research. Performance of different models was investigated in terms of root mean square errors of prediction (RMSEP) and correlation coefficient (r) of validation set of samples. The correlation coefficient of calibration model for SC was 0.965, the correlation coefficient of prediction model for SC was 0.857, and the corresponding RMSEP was 0.562. The results show that visible transmittance technique is a feasible method for non-invasive estimation of fruit juice SC.

  13. A low-noise delta-sigma phase modulator for polar transmitters.

    Science.gov (United States)

    Zhou, Bo

    2014-01-01

    A low-noise phase modulator, using finite-impulse-response (FIR) filtering embedded delta-sigma (ΔΣ) fractional-N phase-locked loop (PLL), is fabricated in 0.18 μ m CMOS for GSM/EDGE polar transmitters. A simplified digital compensation filter with inverse-FIR and -PLL features is proposed to trade off the transmitter noise and linearity. Experimental results show that the presented architecture performs RF phase modulation well with 20 mW power dissipation from 1.6 V supply and achieves the root-mean-square (rms) and peak phase errors of 4° and 8.5°, respectively. The measured and simulated phase noises of -104 dBc/Hz and -120 dBc/Hz at 400-kHz offset from 1.8-GHz carrier frequency are observed, respectively.

  14. CMOS 60-GHz and E-band power amplifiers and transmitters

    CERN Document Server

    Zhao, Dixian

    2015-01-01

    This book focuses on the development of design techniques and methodologies for 60-GHz and E-band power amplifiers and transmitters at device, circuit and layout levels. The authors show the recent development of millimeter-wave design techniques, especially of power amplifiers and transmitters, and presents novel design concepts, such as “power transistor layout” and “4-way parallel-series power combiner”, that can enhance the output power and efficiency of power amplifiers in a compact silicon area. Five state-of-the-art 60-GHz and E-band designs with measured results are demonstrated to prove the effectiveness of the design concepts and hands-on methodologies presented. This book serves as a valuable reference for circuit designers to develop millimeter-wave building blocks for future 5G applications.

  15. Study on moving target detection to passive radar based on FM broadcast transmitter

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Target detection by a noncooperative illuminator is a topic of general interest in the electronic warfare field.First of all,direct-path interference(DPI)suppression which is the technique of bottleneck of moving target detection by a noncooperative frequency modulation(FM) broadcast transmitter is analyzed in this article;Secondly,a space-time-frequency domain synthetic solution to this problem is introduced:Adaptive nulling array processing is considered in the space domain,DPI cancellation based on adaptive fractional delay interpolation(AFDI)technique is used in planned time domain,and long-time coherent integration is utilized in the frequency domain;Finally,an experimental system is planned by considering FM broadcast transmitter as a noncooperative illuminator,Simulation results by real collected data show that the proposed method has a better performance of moving target detection.

  16. Self-detection of x-ray Fresnel transmittivity using photoelectron-induced gas ionization

    CERN Document Server

    Stoupin, Stanislav

    2015-01-01

    Electric response of an x-ray mirror enclosed in a gas flow ionization chamber was studied under the conditions of total external reflection for hard x-rays. It is shown that the electric response of the system as a function of the incidence angle is defined by x-ray Fresnel transmittivity and photon-electron attenuation properties of the mirror material. A simple interpretation of quantum yield of the system is presented. The approach provides non-invasive in-situ diagnostics of hard x-ray optics, easy access to complementary x-ray transmittivity data in x-ray reflectivity experiments and can also pave the way to novel schemes for angle and energy resolving x-ray detectors.

  17. A Low-Noise Delta-Sigma Phase Modulator for Polar Transmitters

    Directory of Open Access Journals (Sweden)

    Bo Zhou

    2014-01-01

    Full Text Available A low-noise phase modulator, using finite-impulse-response (FIR filtering embedded delta-sigma (ΔΣ fractional-N phase-locked loop (PLL, is fabricated in 0.18 μm CMOS for GSM/EDGE polar transmitters. A simplified digital compensation filter with inverse-FIR and -PLL features is proposed to trade off the transmitter noise and linearity. Experimental results show that the presented architecture performs RF phase modulation well with 20 mW power dissipation from 1.6 V supply and achieves the root-mean-square (rms and peak phase errors of 4° and 8.5°, respectively. The measured and simulated phase noises of −104 dBc/Hz and −120 dBc/Hz at 400-kHz offset from 1.8-GHz carrier frequency are observed, respectively.

  18. Standard Test Method for Solar Transmittance (Terrestrial) of Sheet Materials Using Sunlight

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1986-01-01

    1.1 This test method covers the measurement of solar transmittance (terrestrial) of materials in sheet form by using a pyranometer, an enclosure, and the sun as the energy source. 1.2 This test method also allows measurement of solar transmittance at angles other than normal incidence. 1.3 This test method is applicable to sheet materials that are transparent, translucent, textured, or patterned. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  19. Effect of wet etching process on the morphology and transmittance of fluorine doped tin oxide (FTO)

    Science.gov (United States)

    Triana, S. L.; Kusumandari; Suryana, R.

    2016-11-01

    Wet etching process was performed on the surface of FTO. The FTO coated glasses subtrates with size of 2×2 cm covered by screen were patterned using zinc powder and concentrated hydrochloric acid (1 M). The substrates were then cleaned in ultrasonic baths of special detergent(helmanex) diluted in deionized water and isopropanol in sequence. The screens with various of hole size denotes by T32, T49 and T55 were used in order to create a pattern of surface textured. The atomic force microscopy (AFM) image revealed that wet etching process changes the morphology of FTO. It indicates that texturization occured. Moreover, from the UV-Vis Spectrophotometer measurement, the transmittance of FTO increase after wet etching process. The time of etching and pattern of screen were affect to the morphology and the transmittance of FTO.

  20. Transmittance and Reflectance Spectra of Doped-Polyanisidine-Derived Film in the Visible Light Region

    Energy Technology Data Exchange (ETDEWEB)

    Tapia, A K G [Physics Divisio, Institute of Mathematical Sciences and Physics and University of the Philippines Los Banos, College, Laguna, Philippines, 4031 (Philippines); Catedral, M D [Physics Divisio, Institute of Mathematical Sciences and Physics and University of the Philippines Los Banos, College, Laguna, Philippines, 4031 (Philippines); Herrera, M U [Physics Divisio, Institute of Mathematical Sciences and Physics and University of the Philippines Los Banos, College, Laguna, Philippines, 4031 (Philippines); Tamayo, J P [Institute of Chemistry, University of the Philippines Los Banos, College, Laguna, Philippines, 4031 (Philippines); Rosario, E J R del [Institute of Chemistry, University of the Philippines Los Banos, College, Laguna, Philippines, 4031 (Philippines)

    2006-01-01

    Polyanisidine (PAnis) powder was synthesized using a standard procedure. It was doped with Hydrochloric (HCl) and Perchloric (HClO{sub 4}) Acids. The air-dried PAnis powder was then diluted using Dimethyl Formamide (DMF) as solvent and was spread out in a SiOx transparent glass substrate. An amorphous and semi-transparent film was fabricated seen in a polarizing microscope. The spectral analysis was carried out in the visible region from 400 nm to 700 nm. For HCl-doped sample, the high intensity region in the transmittance spectra occurred at the green portion while the high intensity region for the reflectance spectra was seen at the violet portion. Lastly, for the HClO4-doped sample, the peak intensities are at 536 nm and 516 nm for the transmittance and the reflectance spectra, respectively.

  1. Transmittance properties in a magnetized cold plasma-superconductor periodic multilayer.

    Science.gov (United States)

    Aghajamali, Alireza

    2016-08-10

    This study theoretically investigates the transmittance properties of a one-dimensional photonic crystal containing magnetized cold plasma and high-temperature superconductor materials. The cutoff frequency, as a function of the magnetic field, electron density of the plasma layer, and temperature, will be investigated. The results illustrate that the temperature, electron density, and variations of the magnetic field affect the cutoff frequency. In addition, the shift trend in the cutoff frequency proves to be dependent on the polarization due to the presence of polarization-dependent magnetized cold plasma. Moreover, in temperature-dependent transmittance, weak oscillation and intensity can be seen at higher temperatures, which is in sharp contrast to low-temperature superconductor-dielectric structures. The proposed structure could certainly provide helpful information for the design of new types of antennas, reflectors, and high-pass filters at microwave frequency.

  2. Terahertz inverse synthetic aperture radar (ISAR) imaging with a quantum cascade laser transmitter.

    Science.gov (United States)

    Danylov, Andriy A; Goyette, Thomas M; Waldman, Jerry; Coulombe, Michael J; Gatesman, Andrew J; Giles, Robert H; Qian, Xifeng; Chandrayan, Neelima; Vangala, Shivashankar; Termkoa, Krongtip; Goodhue, William D; Nixon, William E

    2010-07-19

    A coherent transceiver using a THz quantum cascade (TQCL) laser as the transmitter and an optically pumped molecular laser as the local oscillator has been used, with a pair of Schottky diode mixers in the receiver and reference channels, to acquire high-resolution images of fully illuminated targets, including scale models and concealed objects. Phase stability of the received signal, sufficient to allow coherent image processing of the rotating target (in azimuth and elevation), was obtained by frequency-locking the TQCL to the free-running, highly stable optically pumped molecular laser. While the range to the target was limited by the available TQCL power (several hundred microwatts) and reasonably strong indoor atmospheric attenuation at 2.408 THz, the coherence length of the TQCL transmitter will allow coherent imaging over distances up to several hundred meters. Image data obtained with the system is presented.

  3. Surface modification of polymethyl methacrylate intraocular lenses by plasma for improvement of antithrombogenicity and transmittance

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lihua; Wu Di; Chen Yashao; Wang Xiaoli; Zhao Guowei; Wan Haiyan [Key Laboratory of Applied Surface and Colloid Chemistry (Shaanxi Normal University), Ministry of Education, School of Chemistry and Materials Science, Chang' an South Road 199, Xi' an 710062 (China); Huang Changzheng [Able Eye Device Co. Ltd, Zhengzhou 450008 (China)

    2009-05-15

    To improve antithrombogenicity and reduce ultraviolet transmittance, polymethyl methacrylate intraocular lenses (PMMA IOLs) were pretreated with Ar plasma and combined with heparin (Hp), with polyglycol (PEG) and with both Hp and PEG in a plasma atmosphere. The resulting modified PMMA IOLs denoted as PEG-PMMA, Hp-PMMA and Hp-PEG-PMMA were characterized by attenuated total reflectance Fourier transfer infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV-vis), contact angle (CA) and platelet adhesion experiments. The results indicated that Hp and PEG had been successfully immobilized onto the surfaces of PMMA IOLs. Antithrombogenicity was improved remarkably and ultraviolet transmittance was reduced as well.

  4. Realization of Transmitter and Receiver Architecture for Downlink Channels in 3-GPP LTE

    Directory of Open Access Journals (Sweden)

    S. Syed Ameer Abbas

    2013-03-01

    Full Text Available Long Term Evolution (LTE, the next generation of radio technologies designed to increase the capacityand speed of mobile networks. The future communication systems require much higher peak rate for the airinterface but very short processing delay. This paper mainly focuses on to improve the processing speedand capability and decrease the processing delay ofthe downlink channels using the parallel processingtechnique. This paper proposes Parallel ProcessingArchitecture for both transmitter and receiver forDownlink channels in 3GPP-LTE. The Processing stepsinclude Scrambling, Modulation, Layer mapping,Precoding and Mapping to the REs in transmitter side. Similarly demapping from the REs, Decoding andDetection, Delayer mapping and Descrambling in Receiver side. Simulation is performed by usingmodelsim and Implementation is achieved using PlanAhead tool and virtex 5 FPGA.Implemented resultsare discussed in terms of RTL design, FPGA editor,power estimation and resource estimation.

  5. SEMI-SUPERVISED RADIO TRANSMITTER CLASSIFICATION BASED ON ELASTIC SPARSITY REGULARIZED SVM

    Institute of Scientific and Technical Information of China (English)

    Hu Guyu; Gong Yong; Chen Yande; Pan Zhisong; Deng Zhantao

    2012-01-01

    Non-collaborative radio transmitter recognition is a significant but challenging issue,sinceit is hard or costly to obtain labeled training data samples.In order to make effective use of the unlabeled samples which can be obtained much easier,a novel semi-supervised classification method named Elastic Sparsity Regularized Support Vector Machine (ESRSVM) is proposed for radio transmitter classification.ESRSVM first constructs an elastic-net graph over data samples to capture the robust and natural discriminating information and then incorporate the information into the manifold learning framework by an elastic sparsity regularization term.Experimental results on 10 GMSK modulated Automatic Identification System radios and 15 FM walkie-talkie radios show that ESRSVM achieves obviously better performance than KNN and SVM,which use only labeled samples for classification,and also outperforms semi-supervised classifier LapSVM based on manifold regularization.

  6. Electrical imprint effects on far infrared (FIR) transmittance spectrum in PZT ferroelectric films

    Science.gov (United States)

    Vivas C., H.

    2015-06-01

    Tunable transmittance response in the 0.1-25 THz range for a lead Zirconate Titanate Ferroelectric film under imprint effects and surface anisotropy is calculated by adapting the classical Landau Devonshire theory and Rouard's method. Induced electrical field is introduced by modulating the P - E polarization profile, while the dielectric permittivity frequency dependence enters into the formalism by taking into account the soft phonon mode E(TO1) contribution in the framework of the Drude-Lorentz model. It is found that two optical states of light transmittance emerge at zero applied field and normal incidence, and the intensities of transmitted light are closely correlated with the strength of imprint and the path of the electrical polarization.

  7. A standard operating procedure for the surgical implantation of transmitters in juvenile salmonids

    Science.gov (United States)

    Liedtke, T.L.; Beeman, J.W.; Gee, L.P.

    2012-01-01

    Biotelemetry is a useful tool to monitor the movements of animals and is widely applied in fisheries research. Radio or acoustic technology can be used, depending on the study design and the environmental conditions in the study area. A broad definition of telemetry also includes the use of Passive Integrated Transponder (PIT) tags, either separately or with a radio or acoustic transmitter. To use telemetry, fish must be equipped with a transmitter. Although there are several attachment procedures available, surgical implantation of transmitters in the abdominal cavity is recognized as the best technique for long-term telemetry studies in general (Stasko and Pincock, 1977; Winter, 1996; Jepsen, 2003), and specifically for juvenile salmonids, Oncorhynchus spp. (Adams and others, 1998a, 1998b; Martinelli and others, 1998; Hall and others, 2009). Studies that use telemetry assume that the processes by which the animals are captured, handled, and tagged, as well as the act of carrying the transmitter, will have minimal effect on their behavior and performance. This assumption, commonly stated as a lack of transmitter effects, must be valid if telemetry studies are to describe accurately the movements and behavior of an entire population of interest, rather than the subset of that population that carries transmitters. This document describes a standard operating procedure (SOP) for surgical implantation of radio or acoustic transmitters in juvenile salmonids. The procedures were developed from a broad base of published information, laboratory experiments, and practical experience in tagging thousands of fish for numerous studies of juvenile salmon movements near Columbia River and Snake River hydroelectric dams. Staff from the Western Fisheries Research Center's Columbia River Research Laboratory (CRRL) frequently have used telemetry studies to evaluate new structures or operations at hydroelectric dams in the Columbia River Basin, and these evaluations typically

  8. High Power K Sub a -band Transmitter for Planetary Radar and Spacecraft Uplink

    Science.gov (United States)

    Bhanji, A. M.; Hoppe, D. J.; Hartop, R. W.; Stone, E. W.; Imbriale, W. A.; Stone, D.; Caplan, M.

    1984-01-01

    A proposed conceptual design of a 400 kW continuous wave (CW)K sub a band transmitter and associated microwave components to be used for planetary radar and serve as a prototype for future spacecraft uplinks is discussed. System requirements for such a transmitter are presented. Performance of the proposed high-power millimeter wave tube, the gyroklystron is discussed. Parameters of the proposed power amplifier, beam supply, and monitor and control devices are also presented. Microwave transmission line components consisting of signal monitoring devices, signal filtering devices, and an overmoded corrugated feed are discussed. Finally, an assessment of the state of the art technology to meet the system requirements is given and possible areas of difficulty are summarized.

  9. Multi-Band Multi-Tone Tunable Millimeter-Wave Frequency Synthesizer For Satellite Beacon Transmitter

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2016-01-01

    This paper presents the design and test results of a multi-band multi-tone tunable millimeter-wave frequency synthesizer, based on a solid-state frequency comb generator. The intended application of the synthesizer is in a satellite beacon transmitter for radio wave propagation studies at K-band (18 to 26.5 GHz), Q-band (37 to 42 GHz), and E-band (71 to 76 GHz). In addition, the architecture for a compact beacon transmitter, which includes the multi-tone synthesizer, polarizer, horn antenna, and power/control electronics, has been investigated for a notional space-to-ground radio wave propagation experiment payload on a small satellite. The above studies would enable the design of robust high throughput multi-Gbps data rate future space-to-ground satellite communication links.

  10. Acoustic imaging and mirage effects with high transmittance in a periodically perforated metal slab

    Science.gov (United States)

    Zhao, Sheng-Dong; Wang, Yue-Sheng; Zhang, Chuanzeng

    2016-11-01

    In this paper, we present a high-quality superlens to focus acoustic waves using a periodically perforated metallic structure which is made of zinc and immersed in water. By changing a geometrical parameter gradually, a kind of gradient-index phononic crystal lens is designed to attain the mirage effects. The acoustic waves can propagate along an arc-shaped trajectory which is precisely controlled by the angle and frequency of the incident waves. The negative refraction imaging effect depends delicately on the transmittance of the solid structure. The acoustic impedance matching between the solid and the liquid proposed in this article, which is determined by the effective density and group velocity of the unit-cell, is significant for overcoming the inefficiency problem of acoustic devices. This study focuses on how to obtain the high transmittance imaging and mirage effects based on the adequate material selection and geometrical design.

  11. Determination and application of location and angular orientation of a pill transmitter within a body

    Science.gov (United States)

    Schipper, John F. (Inventor)

    2009-01-01

    A mobile pill transmitter system that moves through or adjacent to one or more organs in an animal's body and that provides signals from which the pill's present location and/or present angular orientation can be determined. The system also provides signals from which the present roll angle of the pill, about a selected axis, can be determined. When the location coordinates and the roll angle of the pill are within selected ranges, an aperture on the pill container releases a selected chemical into or onto the body. Optionally, the pill as it moves also provides a sequence of visually perceptible images; the times for image formation may correspond to times at which the pill transmitter system location or image satisfies one or at least four different criteria.

  12. High Performance Design of 100Gb/s DPSK Optical Transmitter

    DEFF Research Database (Denmark)

    Das, Bhagwan; Abdullah, M.F.L; Shah, Nor Shahihda Mohd;

    2016-01-01

    High performance communication systems require high performance devices for exchanging information at a faster rate. These devices are experiencing several challenges e.g. bandwidth limitations, power limitations, design limitations and etc. The existing techniques are lacking in providing high...... performance output simultaneously by maintaining actual parameters of device. In this work, high performance 100Gb/s optical DPSK transmitter design is realized in Field Programming Gate (FPGA) using time constraint technique. Before applying the proposed technique actual FPGA’s frequency was 0.2 GHz......, high time score and low slack time. The high performance design is realized without disturbing actual bandwidth, power consumption and other parameters of the design. The proposed high performance design of 100Gb/s optical transmitter can be used with existing optical communication system to develop...

  13. Development and testing of attachment methods for pop-up satellite archival transmitters in European eel

    DEFF Research Database (Denmark)

    Økland, Finn; Thorstad, Eva B.; Westerberg, Håkan

    2013-01-01

    Background Four methods for attaching pop-up satellite transmitters to European eel were tested in the laboratory by recording long-term tag retention, growth and survival; short-term behavioral responses; and physical damage from attachments. Results All eels survived until they lost their tag...... migration studies based on a long tag retention time, minimal behavioral reactions, negligible damage to the swimming muscle, and minimal physical damage both for fish retaining and losing the tag. Although tag retention was 50% over six months, those losing their tags still retained them for 114 to 134...... from 275 silver eels released on European coasts equipped with pop-up satellite transmitters or similarly sized pop-up data storage tags to study the ocean spawning migration indicated a large premature tag release. This was partly related to mechanical tag loss, but probably mainly to a high predation...

  14. 47 CFR 95.217 - (R/C Rule 17) May I operate my R/C station transmitter by remote control?

    Science.gov (United States)

    2010-10-01

    ... transmitter by remote control? 95.217 Section 95.217 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... control? (a) You may not operate an R/C transmitter by radio remote control. (See R/C Rule 12, § 95.212.) (b) You may operate an R/C transmitter by wireline remote control if you obtain specific approval in...

  15. Correspondence Between Continuous and Discrete 2 Flux Models for Reflectance and Transmittance of Diffusing Layers

    OpenAIRE

    Hébert, M.; Becker, J.-M.

    2008-01-01

    This paper provides a theoretical connection between two different mathematical models dedicated to the reflectance and the transmittance of diffusing layers. The Kubelka–Munk model proposes a continuous description of scattering and absorption for two opposite diffuse fluxes in a homogeneous layer (continuous two-flux model). On the other hand, Kubelka's layering model describes the multiple reflections and transmissions of light taking place between various superposed diffusing layers (disc...

  16. Evidence that histamine is the inhibitory transmitter of the auditory interneuron ON1 of crickets.

    Science.gov (United States)

    Skiebe, P; Corrette, B J; Wiese, K

    1990-08-24

    The omega neurons of crickets are connected with each other by reciprocal inhibition. This inhibition could be mimicked by bath-applied histamine and blocked by histamine H1-antagonists. Histamine, like ON1, also influenced the ascending interneuron AN2, so that its response pattern more closely reflected the temporal structure of the calling song. This evidence strongly suggests that histamine is the inhibitory transmitter of the ON1s.

  17. BK potassium channels control transmitter release at CA3-CA3 synapses in the rat hippocampus.

    Science.gov (United States)

    Raffaelli, Giacomo; Saviane, Chiara; Mohajerani, Majid H; Pedarzani, Paola; Cherubini, Enrico

    2004-05-15

    Large conductance calcium- and voltage-activated potassium channels (BK channels) activate in response to calcium influx during action potentials and contribute to the spike repolarization and fast afterhyperpolarization. BK channels targeted to active zones in presynaptic nerve terminals have been shown to limit calcium entry and transmitter release by reducing the duration of the presynaptic spike at neurosecretory nerve terminals and at the frog neuromuscular junction. However, their functional role in central synapses is still uncertain. In the hippocampus, BK channels have been proposed to act as an 'emergency brake' that would control transmitter release only under conditions of excessive depolarization and accumulation of intracellular calcium. Here we demonstrate that in the CA3 region of hippocampal slice cultures, under basal experimental conditions, the selective BK channel blockers paxilline (10 microM) and iberiotoxin (100 nM) increase the frequency, but not the amplitude, of spontaneously occurring action potential-dependent EPSCs. These drugs did not affect miniature currents recorded in the presence of tetrodotoxin, suggesting that their action was dependent on action potential firing. Moreover, in double patch-clamp recordings from monosynaptically interconnected CA3 pyramidal neurones, blockade of BK channels enhanced the probability of transmitter release, as revealed by the increase in success rate, EPSC amplitude and the concomitant decrease in paired-pulse ratio in response to pairs of presynaptic action potentials delivered at a frequency of 0.05 Hz. BK channel blockers also enhanced the appearance of delayed responses, particularly following the second action potential in the paired-pulse protocol. These results are consistent with the hypothesis that BK channels are powerful modulators of transmitter release and synaptic efficacy in central neurones.

  18. Robust Short-Pulse, High-Peak-Power Laser Transmitter for Optical Communications

    Science.gov (United States)

    Wright, Malcolm W.

    2009-01-01

    We report on a pulsed fiber based master oscillator power amplifier laser at 1550 nm to support moderate data rates with high peak powers in a compact package suitable for interplanetary optical communications. To accommodate pulse position modulation, the polarization maintaining laser transmitter generates pulses from 0.1 to 1 ns with variable duty cycle over a pulse repetition frequency range of 10 to 100 MHz.

  19. Evidence that dorsally mounted satellite transmitters affect migration chronology of Northern Pintails

    Science.gov (United States)

    Hupp, Jerry; Kharitonov, Sergei; Yamaguchi, Noriyuki M.; Ozaki, K.; Flint, Paul L.; Pearce, John M.; Tokita, Ken-ichi; Shimada, Tetsuo; Higuchi, Hiroyoshi

    2015-01-01

    We compared migration movements and chronology between Northern Pintails (Anas acuta) marked with dorsally mounted satellite transmitters and pintails marked only with tarsus rings. During weekly intervals of spring and autumn migration between their wintering area in Japan and nesting areas in Russia, the mean distance that ringed pintails had migrated was up to 1000 km farther than the mean distance radiomarked pintails migrated. Radiomarked pintails were detected at spring migration sites on average 9.9 days (90 % CI 8.0, 11.8) later than ringed pintails that were recovered within 50 km. Although ringed and radiomarked pintails departed from Japan on similar dates, the disparity in detection of radiomarked versus ringed pintails at shared sites increased 7.7 days (90 % CI 5.2, 10.2) for each 1000 km increase in distance from Japan. Thus, pintails marked with satellite transmitters arrived at nesting areas that were 2500 km from Japan on average 19 days later than ringed birds. Radiomarked pintails were detected at autumn migration stopovers on average 13.1 days (90 % CI 9.8, 16.4) later than ringed birds that were recovered within 50 km. We hypothesize that dorsal attachment of 12–20 g satellite transmitters to Northern Pintails increased the energetic cost of flight, which resulted in more rapid depletion of energetic reserves and shortened the distance pintails could fly without refueling. Radiomarked pintails may have used more stopovers or spent longer periods at stopovers. causing their migration schedule to diverge from ringed pintails. We urge further evaluation of the effects of dorsally mounted transmitters on migration chronology of waterfowl.

  20. Light scattering and light transmittance in intraocular lenses explanted because of optic opacification.

    Science.gov (United States)

    Michelson, Jennifer; Werner, Liliana; Ollerton, Andrew; Leishman, Lisa; Bodnar, Zachary

    2012-08-01

    To assess light scattering and light transmittance in intraocular lenses (IOLs) explanted because of optic opacification. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Poly(methyl methacrylate) (PMMA) IOLs with snowflake degeneration, hydrophilic acrylic IOLs with different calcification patterns, and 1 calcified silicone IOL explanted from an eye with asteroid hyalosis were studied with gross and light microscopy. Light scattering was measured with an EAS-1000 Scheimpflug camera. Light transmittance was measured with a Lambda 35 UV/Vis spectrophotometer (single-beam configuration with RSA-PE-20 integrating sphere). Analyses were performed at room temperature in the hydrated state and compared with controls. The study evaluated 8 PMMA IOLs, 22 hydrophilic acrylic IOLs, and 1 silicone IOL. Light scattering was as follows: 208 to 223 computer-compatible tapes (CCTs) for PMMA IOLs with snowflake degeneration (control = 9 CCTs); 90 to 227 CCTs for calcified hydrophilic acrylic IOLs (controls = 12 to 23 CCTs); 223 CCTs for the calcified silicone IOL (control = 5 CCTs). The mean light transmittance in the visible light spectrum was 81.08% to 97.10% for PMMA IOLs (control = 98.80%); 78.94% to 97.32% for hydrophilic acrylic IOLs (controls = 97.32% to 98.66%); 94.68% for the silicone IOL (control = 97.74%). Intraocular lens opacification led to very high levels of light scattering and a potential for decreased light transmittance, which play a role in the development of symptoms such as glare and halos, decreased contrast sensitivity, and eventually decreased visual acuity. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  1. Optimal power allocation of a single transmitter-multiple receivers channel in a cognitive sensor network

    KAUST Repository

    Ayala Solares, Jose Roberto

    2012-08-01

    The optimal transmit power of a wireless sensor network with one transmitter and multiple receivers in a cognitive radio environment while satisfying independent peak, independent average, sum of peak and sum of average transmission rate constraints is derived. A suboptimal scheme is proposed to overcome the frequency of outages for the independent peak transmission rate constraint. In all cases, numerical results are provided for Rayleigh fading channels. © 2012 IEEE.

  2. Propagation of ovine prions from "poor" transmitter scrapie isolates in ovine PrP transgenic mice.

    Science.gov (United States)

    Thackray, Alana M; Hopkins, Lee; Lockey, Richard; Spiropoulos, John; Bujdoso, Raymond

    2012-02-01

    Ovine prion strains have typically been identified by their transmission properties, which include incubation time and lesion profile, in wild type mice. The existence of scrapie isolates that do not propagate in wild type mice, defined here as "poor" transmitters, are problematic for conventional prion strain typing studies as no incubation time or neuropathology can be recorded. This may arise because of the presence of an ovine prion strain within the original inoculum that does not normally cross the species barrier into wild type mice or the presence of a low dose of an infectious ovine prion strain that does. Here we have used tg59 and tg338 mouse lines, which are transgenic for ovine ARQ or VRQ PrP, respectively, to strain type "poor" transmitter ovine scrapie isolates. ARQ and VRQ homozygous "poor" transmitter scrapie isolates were successfully propagated in both ovine PrP transgenic mouse lines. We have used secondary passage incubation time, PrPSc immunohistochemistry and molecular profile, to show that different prion strains can be isolated from different "poor" transmitter samples during serial passage in ovine PrP transgenic mice. Our observations show that poor or inadequate transmissibility of some classical scrapie isolates in wild type mice is associated with unique ovine prion strains in these particular sheep scrapie samples. In addition, the analysis of the scrapie isolates used here revealed that the tg338 mouse line was more versatile and more robust at strain typing ovine prions than tg59 mice. These novel observations in ovine PrP transgenic mice highlight a new approach to ovine prion strain typing.

  3. Intraperitoneal implantation of life-long telemetry transmitters in three rehabilitated harbor seal pups.

    Science.gov (United States)

    Horning, Markus; Haulena, Martin; Rosenberg, Justin F; Nordstrom, Chad

    2017-05-25

    Pinnipeds, including many phocid species of concern, are inaccessible and difficult to monitor for extended periods using conventional, externally attached telemetry devices that are shed during the annual molt. Archival satellite transmitters were implanted intraperitoneally into three stranded Pacific harbor seal pups (Phoca vitulina richardii) that completed rehabilitation, to evaluate the viability of this surgical technique for the deployment of life long telemetry devices in phocids. The life history transmitters record information throughout the life of the host and transmit data to orbiting satellites after extrusion following death. Surgeries were performed under general anesthesia and a single transmitter was inserted into the ventrocaudal abdominal cavity via a 7-8 cm incision along the ventral midline between the umbilicus and pubic symphysis or preputial opening in each animal. Surgeries lasted from 45 to 51 min, and anesthesic times ranged from 55 to 79 min. All animals recovered well, were released into dry holding pens overnight, and were given access to water the following day. All three animals exhibited an expected inflammatory response, with acute phase responses lasting approximately three to four weeks. All three animals were tracked via externally attached satellite transmitters after release at 58 to 78 days following surgery, and minimum post-release survival was confirmed through continued movement data received over 278 to 289 days. The initial findings of low morbidity and zero mortality encountered during captive observation and post-release tracking periods support the viability of this surgical technique for the implantation of long-term telemetry devices in phocids.

  4. Pyrolyzed Photoresist Electrodes for Integration in Microfluidic Chips for Transmitter Detection from Biological Cells

    DEFF Research Database (Denmark)

    Larsen, Simon Tylsgaard; Argyraki, Aikaterini; Amato, Letizia

    2013-01-01

    In this study, we show how pyrolyzed photoresist carbon electrodes can be used for amperometric detection of potassium-induced transmitter release from large groups of neuronal PC 12 cells. This opens the way for the use of carbon film electrodes in microfabricated devices for neurochemical drug ...... by the difference in photoresist viscosity. By adding a soft bake step to the fabrication procedure, the flatness of pyrolyzed AZ 5214 electrodes could be improved which would facilitate their integration in microfluidic chip devices....

  5. Design of an Omnidirectional Multibeam Transmitter for High-Speed Indoor Wireless Communications

    OpenAIRE

    Jaw-Luen Tang; Yao-Wen Chang

    2010-01-01

    For future high speed indoor wireless communication, diffuse wireless optical communications offer more robust optical links against shadowing than line-of-sight links. However, their performance may be degraded by multipath dispersion arising from surface reflections. We have developed a multipath diffusive propagation model capable of providing channel impulse responses data. It is aimed to design and simulate any multibeam transmitter under a variety of indoor environments. In this paper,...

  6. Release of chemical transmitters from cell bodies and dendrites of nerve cells

    OpenAIRE

    De-Miguel, Francisco F.; Nicholls, John G.

    2015-01-01

    Papers in this issue concern extrasynaptic transmission, namely release of signalling molecules by exocytosis or diffusion from neuronal cell bodies, dendrites, axons and glia. Problems discussed concern the molecules, their secretion and importance for normal function and disease. Molecules secreted extrasynaptically include transmitters, peptides, hormones and nitric oxide. For extrasynaptic secretion, trains of action potentials are required, and the time course of release is slower than a...

  7. Comparison of cost and complexity for various 16-QAM transmitter structures in coherent optical systems

    Science.gov (United States)

    Al-Bermani, Ali; Noé, Reinhold

    2016-02-01

    This article present several possible implementations for an optical square 16-QAM transmitter structures. Two efficient carrier phase estimation techniques with feed-forward structure have been tested in a real-time transmission and compared with each other to present the influence of phase noise; Blind Phase Search (BPS) and QPSK partitioning. 2.5 Gbit/s synchronous coherent 16-QAM data is transmitted and received in a real-time heterodyne setup with BER below FEC (7% overhead) threshold.

  8. Upgrade of Tuning-position Display for SFC 200 kW Transmitter Anode Circuit

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It is necessary to display of precise position of anode plate tuning device for 200 kW transmitter.Therefore parameters can be conveniently preset in different frequency to tealize frequency replacing and impedance matching of D-circuit.Photo-electricity coding was originally used for angle position of old system.But after ten years’operation,it can’t precisely display position of circuit element movement because its grating was

  9. Application of Near Infrared Transmittance Spectroscopy (NITS)in Determining Amylose Content of Rice Grain

    Institute of Scientific and Technical Information of China (English)

    XIAO Xin; XIE Xin-hua; CHEN Yi; LUO Weng-yong; CHEN Jian-wei; LIU Yan-zhuo; MAO Xing-xue; LI Xiao-fang

    2004-01-01

    Rice samples were scanned with a Foss Tecator Infratec and their amylose content was determined using a standard wet chemical method. Calibration software along with several mathematical treatments of the sample spectra and several regression methods was used to optimize a near infrared transmittance spectroscopy equation for determining rice amylose content. The standard error of calibration, standard error of cross-validation and regression squared of the calibration were 1.489, 1.761 and 0.885, respectively.

  10. Extremely high frequency (EHF) satellite communications (SATCOM) technology-transmitters and receivers

    Science.gov (United States)

    Raue, Jorg E.

    1983-10-01

    During the past three years, interest in satellite communications in the frequency bands above Ku-band has expanded dramatically. As a result, a number of key technology developments, targeted to meet specific next generation spaceborne needs, were undertaken. The state-of-the-art in solid state power transmitters and low noise receivers, including critical passive component technology, is presented. This includes filters as well as a series of rugged high performance ferrite components such as isolators, circulators and latching switches.

  11. High optical transmittance of aluminum ultrathin film with hexagonal nanohole arrays as transparent electrode

    KAUST Repository

    Du, Qing Guo

    2016-02-24

    We fabricate samples of aluminum ultrathin films with hexagonal nanohole arrays and characterize the transmission performance. High optical transmittance larger than 60% over a broad wavelength range from 430 nm to 750 nm is attained experimentally. The Fano-type resonance of the excited surface plasmon plaritons and the directly transmitted light attribute to both of the broadband transmission enhancement and the transmission suppression dips. © 2016 Optical Society of America.

  12. Implementation of the SNR high-speed transport protocol (the transmitter part)

    OpenAIRE

    Mezhoud, Farah.

    1995-01-01

    The major problem addressed by this research is how to implement a transport protocol invented especially for high speed networking using the current workstations, so that the high throughput promised by the protocol will be achieved. The approach taken was to implement the SNR protocol, a transport protocol for high speed networking, named after its inventors, and composed of eight different machines (four transmitter and four receiver), using three Unix workstations connected with FDDI, all...

  13. Dual-Band Transmitter and Stabilization Blade Antenna for Experimental Rocket Telemetry Application

    OpenAIRE

    Bouché, Rémy; Ghiotto, Anthony

    2016-01-01

    IEEE MTT-S Undergraduate Scholarships Reports; This report summarizes the results of research activity conducted during 2015, supported by the MTT-S Undergraduate research scholarship. The aim of this project is to design and manufacture a dual-band transmitter, working at 870 MHz and 2.45 GHz, using an aerodynamic blade antenna. This kind of antenna allows to transmit data while stabilizing the rocket. It also includes the design of a diplexer and a splitter working on both frequencies.

  14. Optical fiber ultrasound transmitter with electrospun carbon nanotube-polymer composite

    Science.gov (United States)

    Poduval, Radhika K.; Noimark, Sacha; Colchester, Richard J.; Macdonald, Thomas J.; Parkin, Ivan P.; Desjardins, Adrien E.; Papakonstantinou, Ioannis

    2017-05-01

    All-optical ultrasound transducers are promising for imaging applications in minimally invasive surgery. In these devices, ultrasound is transmitted and received through laser modulation, and they can be readily miniaturized using optical fibers for light delivery. Here, we report optical ultrasound transmitters fabricated by electrospinning an absorbing polymer composite directly onto the end-face of optical fibers. The composite coating consisting of an aqueous dispersion of multi-walled carbon nanotubes (MWCNTs) in polyvinyl alcohol was directly electrospun onto the cleaved surface of a multimode optical fiber and subsequently dip-coated with polydimethylsiloxane (PDMS). This formed a uniform nanofibrous absorbing mesh over the optical fiber end-face wherein the constituent MWCNTs were aligned preferentially along individual nanofibers. Infiltration of the PDMS through this nanofibrous mesh onto the underlying substrate was observed and the resulting composites exhibited high optical absorption (>97%). Thickness control from 2.3 μm to 41.4 μm was obtained by varying the electrospinning time. Under laser excitation with 11 μJ pulse energy, ultrasound pressures of 1.59 MPa were achieved at 1.5 mm from the coatings. On comparing the electrospun ultrasound transmitters with a dip-coated reference fabricated using the same constituent materials and possessing identical optical absorption, a five-fold increase in the generated pressure and wider bandwidth was observed. The electrospun transmitters exhibited high optical absorption, good elastomer infiltration, and ultrasound generation capability in the range of pressures used for clinical pulse-echo imaging. All-optical ultrasound probes with such transmitters fabricated by electrospinning could be well-suited for incorporation into catheters and needles for diagnostics and therapeutic applications.

  15. An Electronic Pressure Profile Display system for aeronautic test facilities

    Science.gov (United States)

    Woike, Mark R.

    1990-01-01

    The NASA Lewis Research Center has installed an Electronic Pressure Profile Display system. This system provides for the real-time display of pressure readings on high resolution graphics monitors. The Electronic Pressure Profile Display system will replace manometer banks currently used in aeronautic test facilities. The Electronic Pressure Profile Display system consists of an industrial type Digital Pressure Transmitter (DPI) unit which interfaces with a host computer. The host computer collects the pressure data from the DPI unit, converts it into engineering units, and displays the readings on a high resolution graphics monitor in bar graph format. Software was developed to accomplish the above tasks and also draw facility diagrams as background information on the displays. Data transfer between host computer and DPT unit is done with serial communications. Up to 64 channels are displayed with one second update time. This paper describes the system configuration, its features, and its advantages over existing systems.

  16. Degradation in PV Encapsulation Transmittance: An Interlaboratory Study Towards a Climate-Specific Test

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Annigoni, Eleonora; Ballion, Amal; Bokria, Jayesh G.; Bruckman, Laura S.; Burns, David M.; Chen, Xinxin; Elliott, L.; Feng, J.; French, Roger H.; Fowler, S.; Gu, X.; Hacke, Peter L.; Honeker, C. C.; Kempe, Michael D.; Khonkar, H.; Kohl, M.; Perret-Aebi, Laure-Emmanuelle; Phillips, N. H.; Scott, K. P.; Sculati-Meillaud, F.; Shioda, T.; Suga, S.; Watanabe, S.; Wohlgemuth, John H.

    2015-06-14

    Reduced optical transmittance of encapsulants resulting from ultraviolet (UV) degradation has frequently been identified as a cause of decreased PV module performance through the life of service in the field. The present module safety and qualification standards, however, apply short UV doses only capable of examining design robustness or 'infant mortality' failures. Essential information that might be used to screen encapsulation through product lifetime remains unknown. For example, the relative efficacy of xenon-arc and UVA-340 fluorescent sources or the typical range of activation energy for degradation is not quantified. We have conducted an interlaboratory experiment to provide the understanding that will be used towards developing a climate- and configuration-specific (UV) weathering test. Five representative, known formulations of EVA were studied in addition to one TPU material. Replicate laminated silica/polymer/silica specimens are being examined at 14 institutions using a variety of indoor chambers (including Xenon, UVA-340, and metal-halide light sources) or field aging. The solar-weighted transmittance, yellowness index, and the UV cut-off wavelength, determined from the measured hemispherical transmittance, are examined to provide understanding and guidance for the UV light source (lamp type) and temperature used in accelerated UV aging tests.

  17. An all-digital synthesizable baseband for a delay-based LINC transmitter with reconfigurable resolution

    Institute of Scientific and Technical Information of China (English)

    Han Yue; Qiao Shushan; Hei Yong

    2014-01-01

    The linear amplification with nonlinear component transmitter is a promising solution to high efficiency and high linearity amplification for non-constant envelope signals.An all-digital synthesizable baseband for a delay-based LINC transmitter is implemented.This paper proposes a standard-cell based synthesizable methodology which can be applied in the ASIC process efficiently without performance degradation compared to the manual layout.A scheme to overcome the limited resolution of conventional phase detectors is proposed.It employs alternative phase detector structures to provide reconfigurability for higher resolution after fabricating,resulting in an 11 ps resolution improvement.Due to the PVT variation,an adaptive calibration scheme focusing on the inherent imbalance between two delay lines is depicted,which reveals an effective EVM enhancement of 5.37 dB.This baseband chip is implemented in 0.13 μm CMOS technology,and the transmitter with the baseband has an EVM of-28.96 dB and an ACPR of-29.51 dB,meeting the design requirement.

  18. Comparative Evaluation of Spectral Transmittance of Some Welding Glasses with ANSI Z87.1

    Directory of Open Access Journals (Sweden)

    saeed Rahmani

    2016-04-01

    Full Text Available Background: Welding emits harmful rays to the eyes. We evaluate and compare the UV, blue light and IR transmittance characteristics of some currently available welding safety protectors with ANSI Z87.1 criteria.Materials and Methods: Three type of welding safety protectors (three of each type have been evaluated for spectral transmittance. One-sample T-test was performed to establish is there a statistically significant difference between the standard criteria and UV, blue and IR regions for the welding protectors (α=0.05.Results: In ultraviolet (UV (far and near region, two types of the tested protectors (P1, P2 transmitted lower than the maximum allowable value specified in the standard (P<0.001. In infrared (IR spectrum only one type (P3 transmitted lower than the maximum allowable value specified in the standard (P<0.001. In blue light region, all of the tested protectors transmitted lower than the maximum allowable value specified in the standard (P<0.001.Conclusion: Although all of the tested glasses could meet some parts of the criteria, but none of them could meet the complete spectral transmittance requirements of ANSI Z87.1.

  19. Spectral transmittance and module structure fitting for transmission-mode GaAs photocathodes

    Institute of Scientific and Technical Information of China (English)

    Zhao Jing; Chang Ben-Kang; Xiong Ya-Juan; Zhang Yi-Jun

    2011-01-01

    A transmission-mode GaAs photocathode includes four layers of glass, Si3N4, Gal-xAlxAs and GaAs. A gradientdoping photocathode sample was obtained by molecular beam epitaxy and its transmittance was measured by spectrophotometer from 600 nm to 1100 nm. The theoretical transmittance is derived and simulated based on the matrix formula for thin film optics. The simulation results indicate the influence of the transition layers and the three thin-film layers except glass on the transmittance spectra. In addition, a fitting coefficient needed for error modification enters into the fitted formula. The fitting results show that the relative error in the full spectrum reduces from 19.51% to 4.35% after the formula is modified. The coefficient and the thicknesses are gained corresponding to the minimum relative error, meanwhile each layer and total thin-film thickness deviation in the module can be controlled within 7%.The presence of glass layer roughness, layer interface effects and surface oxides is interpreted on the modification.

  20. A New Position Location System Using DTV Transmitter Identification Watermark Signals

    Directory of Open Access Journals (Sweden)

    Chouinard Jean-Yves

    2006-01-01

    Full Text Available A new position location technique using the transmitter identification (TxID RF watermark in the digital TV (DTV signals is proposed in this paper. Conventional global positioning system (GPS usually does not work well inside buildings due to the high frequency and weak field strength of the signal. In contrast to the GPS, the DTV signals are received from transmitters at relatively short distance, while the broadcast transmitters operate at levels up to the megawatts effective radiated power (ERP. Also the RF frequency of the DTV signal is much lower than the GPS, which makes it easier for the signal to penetrate buildings and other objects. The proposed position location system based on DTV TxID signal is presented in this paper. Practical receiver implementation issues including nonideal correlation and synchronization are analyzed and discussed. Performance of the proposed technique is evaluated through Monte Carlo simulations and compared with other existing position location systems. Possible ways to improve the accuracy of the new position location system is discussed.

  1. Integrated Inductors for RF Transmitters in CMOS/MEMS Smart Microsensor Systems

    Directory of Open Access Journals (Sweden)

    Makoto Ishida

    2007-07-01

    Full Text Available This paper presents the integration of an inductor by complementary metal-oxide-semiconductor (CMOS compatible processes for integrated smart microsensorsystems that have been developed to monitor the motion and vital signs of humans invarious environments. Integration of radio frequency transmitter (RF technology withcomplementary metal-oxide-semiconductor/micro electro mechanical systems (CMOS/MEMS microsensors is required to realize the wireless smart microsensors system. Theessential RF components such as a voltage controlled RF-CMOS oscillator (VCO, spiralinductors for an LC resonator and an integrated antenna have been fabricated and evaluatedexperimentally. The fabricated RF transmitter and integrated antenna were packaged withsubminiature series A (SMA connectors, respectively. For the impedance (50 matching,a bonding wire type inductor was developed. In this paper, the design and fabrication of thebonding wire inductor for impedance matching is described. Integrated techniques for theRF transmitter by CMOS compatible processes have been successfully developed. Aftermatching by inserting the bonding wire inductor between the on-chip integrated antennaand the VCO output, the measured emission power at distance of 5 m from RF transmitterwas -37 dBm (0.2 μW.

  2. High-power magnetron transmitter as an RF source for superconducting linear accelerators

    CERN Document Server

    Kazakevich, Grigory; Flanagan, Gene; Marhauser, Frank; Yakovlev, Vyacheslav; Chase, Brian; Lebedev, Valeri; Nagaitsev, Sergei; Pasquinelli, Ralph; Solyak, Nikolay; Quinn, Kenneth; Wolff, Daniel; Pavlov, Viatcheslav

    2014-01-01

    A concept of a high-power magnetron transmitter for operation within a wideband control feedback loop in phase and amplitude is presented. This transmitter is proposed to drive Superconducting RF (SRF) cavities for intensity-frontier GeV-scale proton/ion linacs. The transmitter performance at the dynamic control was verified in experiments with CW, S-Band, 1 kW magnetrons. The wideband control of magnetrons, required for the superconducting linacs, was realized using the magnetrons, injection-locked by the phase-modulated signals. The capabilities of the magnetrons injection-locked by the phase-modulated signals and adequateness for feeding of SRF cavities were verified by measurements of the transfer function magnitude characteristics of single and 2-cascade magnetrons, by measurements the magnetrons phase performance and by measurements of spectra of the carrier frequency. At the ratio of power of locking signal to output power less than -13 dB (in 2-cascade scheme per magnetron, respectively) we demonstrat...

  3. Multi-Antenna System Design with Bright Transmitters and Blind Receivers

    CERN Document Server

    Li, Liangbin

    2012-01-01

    This paper considers a scenario for multi-input multi-output (MIMO) communication systems when perfect channel state information at the transmitter (CSIT) is given while the equivalent channel state information at the receiver (CSIR) is not available. Such an assumption is valid for the downlink multi-user MIMO systems with linear precoders that depend on channels to all receivers. We propose a concept called dual systems with zero-forcing designs based on the duality principle, originally proposed to relate Gaussian multi-access channels (MACs) and Gaussian broadcast channels (BCs). For the two-user N*2 MIMO BC with N antennas at the transmitter and two antennas at each of the receivers, we design a downlink interference cancellation (IC) transmission scheme using the dual of uplink MAC systems employing IC methods. The transmitter simultaneously sends two precoded Alamouti codes, one for each user. Each receiver can zero-force the unintended user's Alamouti codes and decouple its own data streams using two ...

  4. Degradation in PV Encapsulation Transmittance: An Interlaboratory Study Toward a Climate-Specific Test

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Hacke, Peter L.; Kempe, Michael D.; Wohlgemuth, John H.; Annigoni, Eleonora; Sculati-Meillaud, Fanny; Ballion, Amal; Kohl, Michael; Bokria, Jayesh G.; Bruckman, Laura S.; French, Roger H.; Burns, David; Phillips, Nancy H.; Feng; Jiangtao; Elliott, Lamont; Scott, Kurt P.; Fowler, Sean; Gu, Xiaohong; Honeker, Christian C.; Khonkar, Hussam; Perret-Aebi, Laure-Emmanuelle; Shioda, Tsy

    2015-06-14

    Reduced optical transmittance of encapsulation resulting from ultraviolet (UV) degradation has frequently been identified as a cause of decreased PV module performance through the life of installations in the field. The present module safety and qualification standards, however, apply short UV doses only capable of examining design robustness or 'infant mortality' failures. Essential information that might be used to screen encapsulation through product lifetime remains unknown. For example, the relative efficacy of xenon-arc and UVA-340 fluorescent sources or the typical range of activation energy for degradation is not quantified. We have conducted an interlaboratory experiment to provide the understanding that will be used towards developing a climate- and configuration-specific (UV) weathering test. Five representative, known formulations of EVA were studied in addition to one TPU material. Replicate laminated silica/polymer/silica specimens are being examined at 14 institutions using a variety of indoor chambers (including Xe, UVA-340, and metal-halide light sources) or field aging. The solar-weighted transmittance, yellowness index, and the UV cut-off wavelength, determined from the measured hemispherical transmittance, are examined to provide understanding and guidance for the UV light source (lamp type) and temperature used in accelerated UV aging tests. Index Terms -- reliability, durability, thermal activation.

  5. Configurable Transmitter and Systolic Channel Estimator Architectures for Data-Dependent Superimposed Training Communications Systems

    Directory of Open Access Journals (Sweden)

    E. Romero-Aguirre

    2012-01-01

    Full Text Available In this paper, a configurable superimposed training (ST/data-dependent ST (DDST transmitter and architecture based on array processors (APs for DDST channel estimation are presented. Both architectures, designed under full-hardware paradigm, were described using Verilog HDL, targeted in Xilinx Virtex-5 and they were compared with existent approaches. The synthesis results showed a FPGA slice consumption of 1% for the transmitter and 3% for the estimator with 160 and 115 MHz operating frequencies, respectively. The signal-to-quantization-noise ratio (SQNR performance of the transmitter is about 82 dB to support 4/16/64-QAM modulation. A Monte Carlo simulation demonstrates that the mean square error (MSE of the channel estimator implemented in hardware is practically the same as the one obtained with the floating-point golden model. The high performance and reduced hardware of the proposed architectures lead to the conclusion that the DDST concept can be applied in current communications standards.

  6. Degradation in PV Encapsulation Transmittance: An Interlaboratory Study Towards a Climate-Specific Test: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Annigoni, Eleonora; Ballion, Amal; Bokria, Jayesh G.; Bruckman, Laura S.; Burns, David M.; Chen, Xinxin; Elliott, Lamont; Feng, Jiangtao; French, Roger H.; Fowler, Sean; Gu, Xiaohong; Hacke, Peter L.; Honeker, Christian C.; Kempe, Michael D.; Khonkar, Hussam; Kohl, Michael; Perret-Aebi, Laure-Emmanuelle; Phillips, Nancy H.; Scott, Kurt P.; Sculati-Meillaud, Fanny; Shioda, Tsuyos

    2015-08-12

    Reduced optical transmittance of encapsulants resulting from ultraviolet (UV) degradation has frequently been identified as a cause of decreased PV module performance through the life of service in the field. The present module safety and qualification standards, however, apply short UV doses only capable of examining design robustness or 'infant mortality' failures. Essential information that might be used to screen encapsulation through product lifetime remains unknown. For example, the relative efficacy of xenon-arc and UVA-340 fluorescent sources or the typical range of activation energy for degradation is not quantified. We have conducted an interlaboratory experiment to provide the understanding that will be used towards developing a climate- and configuration-specific (UV) weathering test. Five representative, known formulations of EVA were studied in addition to one TPU material. Replicate laminated silica/polymer/silica specimens are being examined at 14 institutions using a variety of indoor chambers (including Xenon, UVA-340, and metal-halide light sources) or field aging. The solar-weighted transmittance, yellowness index, and the UV cut-off wavelength, determined from the measured hemispherical transmittance, are examined to provide understanding and guidance for the UV light source (lamp type) and temperature used in accelerated UV aging tests.

  7. Calibrating acoustic acceleration transmitters for estimating energy use by wild adult Pacific salmon.

    Science.gov (United States)

    Wilson, S M; Hinch, S G; Eliason, E J; Farrell, A P; Cooke, S J

    2013-03-01

    This study is the first to calibrate acceleration transmitters with energy expenditure using a vertebrate model species. We quantified the relationship between acoustic accelerometer output and oxygen consumption across a range of swim speeds and water temperatures for Harrison River adult sockeye salmon (Oncorhynchus nerka). First, we verified that acceleration transmitters with a sampling frequency of 10 Hz could be used as a proxy for movement in sockeye salmon. Using a mixed effects model, we determined that tailbeat frequency and acceleration were positively correlated (pAcceleration (pspeed while fork length (p=0.051) was negatively related to swim speed. Oxygen consumption and accelerometer output (plinear relationship and were temperature dependent (pspeed was 1.25±0.03 body lengths s(-1) and cost of transport was 3.39±0.17 mg O(2) kg(-1)min(-1), averaged across the three detected fish. Acceleration transmitters can be effectively used to remotely evaluate fine-scale behavior and estimate energy consumption of adult Pacific salmon throughout their homeward spawning migration.

  8. Large-conductance calcium-activated potassium channels facilitate transmitter release in salamander rod synapse.

    Science.gov (United States)

    Xu, Jian Wei; Slaughter, Malcolm M

    2005-08-17

    Large-conductance calcium-activated potassium (BK) channels are colocalized with calcium channels at sites of exocytosis at the presynaptic terminals throughout the nervous system. It is expected that their activation would provide negative feedback to transmitter release, but the opposite is sometimes observed. Attempts to resolve this apparent paradox based on alterations in action potential waveform have been ambiguous. In an alternative approach, we investigated the influence of this channel on neurotransmitter release in a nonspiking neuron, the salamander rod photoreceptors. Surprisingly, the BK channel facilitates calcium-mediated transmitter release from rods. The two presynaptic channels form a positive coupled loop. Calcium influx activates the BK channel current, leading to potassium efflux that increases the calcium current. The normal physiological voltage range of the rod is well matched to the dynamics of this positive loop. When the rod is further depolarized, then the hyperpolarizing BK channel current exceeds its facilitatory effect, causing truncation of transmitter release. Thus, the calcium channel-BK channel linkage performs two functions at the synapse: nonlinear potentiator and safety brake.

  9. Demeter/ICE Experiment: Study of low frequency transmitter intensity variations

    Science.gov (United States)

    Boudjada, M. Y.; Moldovan, I.; Schwingenschuh, K.; Al-Haddad, E.; Biagi, P. F.; Parrot, M.

    2012-04-01

    We report on low frequency (LF) transmitter signal recorded by the 'Instrument Capteur Electrique' (ICE) experiment onboard the DEMETER micro-satellite. We mainly consider the signal emitted by the Brasov broadcasting station (25.60E, 45.75N) at frequency of about 153 kHz. We analyze the reception conditions of this transmitter several weeks before the occurrence of the Vrancea earthquakes, on October, 27th, 2004. Ground-based observations revealed the presence of sudden decrease of the Y-component of the magnetic field at Muntele Rosu Observatory (Romania), at about 68 km from the epicenter, as reported by Moldovan et al. (Rom. Journ. Phys., Vol. 54, Nos. 1-2, p. 249-261, Bucharest, 2009). In this contribution we attempt to check if the LF Brasov signal was also subject to similar disturbances as observed by the ground-station. We focus on the variation of the LF transmitter intensity levels, several weeks before and after the Vrancea earthquake occurrence. We discuss the physical parameters which may disturb the signal reception in particular the geomagnetic activity and the signal to noise ratios.

  10. Study of latitudinal effects on VLF transmitter signals recorded by DEMETER/ICE experiment

    Science.gov (United States)

    Boudjada, M. Y.; Schwingenschuh, K.; Berthelier, J. J.; Döller, R.; Galopeau, P. H. M.; Parrot, M.; Stangl, G.; Biernat, H.; Voller, W.; Besser, B.

    2010-05-01

    We report on VLF transmitter signals observed by the ‘Instrument Capteur Electrique' (ICE) experiment onboard the DEMETER micro-satellite. The DEMETER polar and circular sun-synchronous orbits lead to cover an invariant latitude range between -65° and +65° where up- and down-going half-orbits correspond to night-time (22:00 LT) and day-time (10:00 LT), respectively. The DEMETER orbit features permit to record signals emitted by some VLF ground-stations and detected by ICE experiment. We consider three transmitter signals emitted by stations in Europe (Germany, DFY, 16.58 kHz), in Asia (Japan, JP, 17.8 kHz) and in Australia (Australia, NWC, 19.8 kHz). We study the variation of these VLF signals taking into consideration the DEMETER satellite latitudes .We emphasis on latitudes where the satellite is close to the Earth's sub-auroral regions. We discuss particularly the presence, or not, of auroral magnetic activity effect on the VLF transmitter signals.

  11. Secret-key Agreement with Channel State Information at the Transmitter

    CERN Document Server

    Khisti, Ashish; Wornell, Gregory

    2010-01-01

    We study the capacity of secret-key agreement over a wiretap channel with state parameters. The transmitter communicates to the legitimate receiver and the eavesdropper over a discrete memoryless wiretap channel with a memoryless state sequence. The transmitter and the legitimate receiver generate a shared secret key, that remains secret from the eavesdropper. No public discussion channel is available. The state sequence is known noncausally to the transmitter. We derive lower and upper bounds on the secret-key capacity. The lower bound involves constructing a common state reconstruction sequence at the legitimate terminals and binning the set of reconstruction sequences to obtain the secret-key. For the special case of Gaussian channels with additive interference (secret-keys from dirty paper channel) our bounds differ by 0.5 bit/symbol and coincide in the high signal-to-noise-ratio and high interference-to-noise-ratio regimes. For the case when the legitimate receiver is also revealed the state sequence, we...

  12. A dual-mode 6-9 GHz transmitter for OFDM-UWB

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yunfeng; Gao Ting; Li Wei; Li Ning; Ren Junyan, E-mail: jyren@fudan.edu.cn, E-mail: w-li@fudan.edu.cn [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

    2011-05-15

    This paper presents a fully integrated dual-mode 6 to 9 GHz transmitter for both WiMedia and China MB-OFDM UWB applications. The proposed transmitter consists of a dual-mode I/QLPF, an up-conversion mixer, a two-stage power driver amplifier and a broadband high-speed frequency divider with LO buffers for I/Q LO carrier generation. The measurement results show that the gain ripple of the transmitter is within {+-}1.5/{+-}2.8 dB from 6 to 8.7/9 GHz. The output IP3 is about +13.2 dBm, the output 1dBCP is around +2.8 dBm, and the LO leakage/sideband rejection ratio is about -35/-38 dBc. The ESD protected chip is fabricated with a TSMC 0.13 {mu}m RFCMOS process with a die size of 1.6 x 1.3 mm{sup 2} and the core circuit consumes only 46 mA under a 1.2 V supply. (semiconductor integrated circuits)

  13. Analysis of Intermodulation Distortion in OFDM Based Transmitter Using EER Technique

    Directory of Open Access Journals (Sweden)

    S. Matejka

    2016-06-01

    Full Text Available During the last two decades, new digital modulation systems have appeared in the audio broadcasting. Such broadcasting systems require new transmitters’ concepts to enable the transmission of digitally modulated signals. Moreover, the selected modulation schemes (e.g. orthogonal frequency division multiplexing require a high linearity power stage, which typically exhibits low efficiency due to high peak-toaverage power ratio of the modulated signal. One of the promising transmitter concepts is the Kahn envelope elimination and restoration technique, where the original Cartesian in-phase and quadrature baseband signals are transformed to the envelope and phase signals. The main advantage of this technique is an ability to employ suitable types of highly efficient amplitude modulation transmitters for envelope amplification, while the phase modulated carrier is produced by an additional phase modulator. The substantial drawback of envelope elimination and restoration is nonideal recombination of linearly distorted amplitude signal and phase modulated carrier at the output power stage. The aim of this paper is twofold. Firstly, to analyze the effect of the envelope and phase signals bandwidth limitation on the modulated signal in-channel distortion and out-ofchannel emission. Secondly, to present the performance results as a reference for transmitter designers to properly set the envelope and phase paths to reach required in-channel signal quality and suppress out-of-channel products.

  14. Use of electricity to sedate Lake Trout for intracoelomic implantation of electronic transmitters

    Science.gov (United States)

    Faust, Matthew D.; Vandergoot, Christopher; Hostnik, Eric T.; Binder, Thomas R.; Mida Hinderer, Julia L.; Ives, Jessica T.; Krueger, Charles Conrad

    2017-01-01

    Use of telemetry data to inform fisheries conservation and management is becoming increasingly common; as such, fish typically must be sedated before surgical implantation of transmitters into the coelom. Given that no widely available, immediate-release chemical sedative currently exists in North America, we investigated the feasibility of using electricity to sedate Lake Trout Salvelinus namaycush long enough for an experienced surgeon to implant an electronic transmitter (i.e., 180 s). Specifically, our study objectives were to determine (1) whether some combination of electrical waveform characteristics (i.e., duty cycle, frequency, voltage, and pulse type) could sedate Lake Trout for at least 180 s; and (2) whether Lake Trout that were sequentially exposed to continuous DC and pulsed DC had greater rates of spinal injury and short-term mortality than control fish. A Portable Electrosedation System unit was used to sedate hatchery and wild Lake Trout. Dual-frequency pulsed-DC and two-stage approaches successfully sedated Lake Trout and had similar induction and recovery times. Lake Trout sedated using the two-stage approach did not have survival rates or spinal abnormalities that were significantly different from those of control fish. We concluded that electricity was a viable alternative to chemical sedatives for sedating Lake Trout before surgical implantation of an electronic transmitter, but we suggest that Lake Trout and other closely related species (e.g., Arctic Char Salvelinus alpinus) may require morphotype-specific electrical waveforms due to their morphological diversity.

  15. Verilog Based Design and Simulation of MAC and PHY Layers for Zigbee Digital Transmitter

    Directory of Open Access Journals (Sweden)

    Pasala Raja Prakasha Rao

    2014-12-01

    Full Text Available The past several years have witnessed a rapid development in the wireless network area. So far wireless networking has been focused on high-speed and long range applications. Zigbee technology was developed for a Wireless Personal Area Networks (WPAN, aimed at control and military applications with low data rate and low power consumption. Zigbee is a standard defines the set of communication protocols for low-data-rate short-range wireless networking. Zigbee-based wireless devices operate in 868 MHz, 915 MHz, and 2.4 GHz frequency bands. The maximum data rate is 250K bits per second. Zigbee is mainly for battery-powered applications where low data rate, low cost, and long battery life are main requirements. This paper explores Verilog design for various blocks in Zigbee Transmitter architecture for an acknowledgement frame. The word digital has made a dramatic impact on our society. Developments of digital solutions have been possible due to good digital system design and modeling techniques. Further developments have been made and introduced VLSI in order to reduce size of the architecture, to improve speed of operation, improvements in predictability of the circuit behavior. Digital Zigbee Transmitter comprises of Cyclic Redundancy Check, Bit-to-Symbol block, Symbol-to-chip block, Modulator and Pulse shaping block. The work here is to show how we can design Zigbee transmitter with its specifications by using Verilog with less number of slices and Look up tables (LUTs.

  16. 47 CFR 22.303 - Retention of station authorizations; identifying transmitters.

    Science.gov (United States)

    2010-10-01

    ... modifications to facilities pursuant to § 1.929 of this chapter, and added facilities pursuant to § 22.165 must... location where the licensee's current authorization and other records may be found....

  17. High Power RF Test Facility at the SNS

    CERN Document Server

    Kang, Yoon W; Campisi, Isidoro E; Champion, Mark; Crofford, Mark; Davis, Kirk; Drury, Michael A; Fuja, Ray E; Gurd, Pamela; Kasemir, Kay-Uwe; McCarthy, Michael P; Powers, Tom; Shajedul Hasan, S M; Stirbet, Mircea; Stout, Daniel; Tang, Johnny Y; Vassioutchenko, Alexandre V; Wezensky, Mark

    2005-01-01

    RF Test Facility has been completed in the SNS project at ORNL to support test and conditioning operation of RF subsystems and components. The system consists of two transmitters for two klystrons powered by a common high voltage pulsed converter modulator that can provide power to two independent RF systems. The waveguides are configured with WR2100 and WR1150 sizes for presently used frequencies: 402.5 MHz and 805 MHz. Both 402.5 MHz and 805 MHz systems have circulator protected klystrons that can be powered by the modulator capable of delivering 11 MW peak and 1 MW average power. The facility has been equipped with computer control for various RF processing and complete dual frequency operation. More than forty 805 MHz fundamental power couplers for the SNS superconducting linac (SCL) cavitites have been RF conditioned in this facility. The facility provides more than 1000 ft2 floor area for various test setups. The facility also has a shielded cave area that can support high power tests of normal conducti...

  18. Effect of grain size on optical transmittance of birefringent polycrystalline ceramics

    Science.gov (United States)

    Wen, Tzu-Chien

    Polycrystalline ceramics are increasingly used for fabricating windows and domes for the mid infra-red regime (3-5 mum) due to their superior durability as compared to glass and the lower cost of their fabrication and finishing relative to single crystals without significant compromise in optical properties. Due to the noncubic structure, MgF2 and Al2O3 are birefringent ceramics. Birefringence causes scatter of light at the grain boundaries and diminishes in-line transmittance and optical performance. This dissertation presents experimental results and analyses of the grain-size and wavelength dependence of the in-line transmittance of polycrystalline MgF2 and Al2O3. Chapter 2 presents experimental results and analyses of light transmission in polycrystalline MgF2 as a function of the mean grain size at different wavelengths. The scattering coefficient of polycrystalline MgF 2 increased linearly with the mean grain size and inversely with the square of the wavelength of light. These trends are consistent with theoretical models based on both a limiting form of the Raleigh-Gans-Debye theory of particle scattering and light retardation theories that take refractive-index variations along the light path. Chapter 3 investigates the applicability of particle light scattering theories to light attenuation in birefringent polycrystalline ceramics by measuring light transmittance in a model two-phase system. The system consisted of microspheres of silica dispersed in a solution of glycerol in water. It was found that RGD theory showed the systematic deviation for higher particle volume fraction (φ > 0.2) and larger particle size (d p > 1 mum). This result suggested that light scattering models based on single particle scattering are unlikely to provide viable physical explanation for the effect of grain size on light transmittance in birefringent polycrystalline ceramics due to the high volume fraction in dense polycrystalline ceramics. Chapter 4 analyses light

  19. Wind Tunnel Experiments to Assess the Effect of Back-Mounted Radio Transmitters on Bird Body Drag

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The aerodynamic drag of bird bodies was measured in a wind tunnel, with and without back-mounted dummy radio transmitters. Flight performance estimates indicate that...

  20. Calculations of the Total Number of Electrons Along a Ray Path Extending from the Transmitter to the Receiver

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Ionospheric Total Electron Content (TEC) is the total number of electrons in a column of unit cross section extending from the transmitter to the receiver. TEC is...

  1. Public Safety Transmitter Towers, Published in 2006, 1:12000 (1in=1000ft) scale, Washington County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Public Safety Transmitter Towers dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from Field Observation information as of 2006....

  2. A Parameterized yet Accurate Model of Ozone and Water Vapor Transmittance in the Solar-to-near-infrared Spectrum

    Institute of Scientific and Technical Information of China (English)

    LIU Weiyi; QIU Jinhuan

    2012-01-01

    A parameterized transmittance model (PTR) for ozone and water vapor monochromatic transmittance calculation in the solar-to-near-infrared spectrum 0.3-4 μm with a spectral resolution of 5 cm-1 was developed based on the transmittance data calculated by Moderate-resolution Transmittance model (MODTRAN).Polynomial equations were derived to represent the transmittance as functions of path length and airmass for every wavelength based on the least-squares method.Comparisons between the transmittances calculated using PTR and MODTRAN were made,using the results of MODTRAN as a reference.Relative root-mean-square error (RMSre) was 0.823% for ozone transmittance.RMSre values were 8.84% and 3.48% for water vapor transmittance ranges of 1-1 × 10-18and 1-1× 10-3,respectively.In addition,the Stratospheric Aerosol and Gas Experiment II (SAGEII) ozone profiles and University of Wyoming (UWYO)water vapor profiles were applied to validate the applicability of PTR model.RMSre was 0.437% for ozone transmittance.RMSre values were 8.89% and 2.43% for water vapor transmittance ranges of 1-1 × 10-18and 1-1 × 10-6,respectively.Furthermore,the optical depth profiles calculated using the PTR model were compared to the results of MODTRAN.Absolute RMS errors (RMSab) for ozone optical depths were within 0.0055 and 0.0523 for water vapor at all of the tested altitudes.Finally,the comparison between the solar heating rate calculated from the transmittance of PTR and Line-by-Line radiative transfer model (LBLRTM) was performed,showing a maximum deviation of 0.238 K d-1 (6% of the corresponding solar heating rate calculated using LBLRTM).In the troposphere all of the deviations were within 0.08 K d-1.The computational speed of PTR model is nearly two orders of magnitude faster than that of MODTRAN.

  3. Facility Effluent Monitoring Plan determinations for the 600 Area facilities

    Energy Technology Data Exchange (ETDEWEB)

    Nickels, J.M.

    1991-08-01

    This document determines the need for Facility Effluent Monitoring Plans for Westinghouse Hanford Company's 600 Area facilities on the Hanford Site. The Facility Effluent Monitoring Plan determinations were prepared in accordance with A Guide For Preparing Hanford Site Facility Effluent Monitoring Plans (WHC 1991). Five major Westinghouse Hanford Company facilities in the 600 Area were evaluated: the Purge Water Storage Facility, 212-N, -P, and -R Facilities, the 616 Facility, and the 213-J K Storage Vaults. Of the five major facilities evaluated in the 600 Area, none will require preparation of a Facility Effluent Monitoring Plan.

  4. 40-Gb/s star 16-QAM transmitter based on single dual-drive Mach-Zehnder modulator

    Institute of Scientific and Technical Information of China (English)

    Junming Gao; Xinyu Xu; Qingjiang Chang; Yikai Su

    2009-01-01

    We propose a 40-Gb/s star 16-ary quadrature amplitude modulation (16-QAM) transmitter using a single dual-drive Mach-Zehnder modulator (DDMZM). This transmitter is demonstrated through experiment and simulation and shows the advantage of simplicity for implementation. Simulation results indicate that error free performance could be achieved for the generated signal after 80-km standard single-mode fiber (SSMF) transmission with coherent detection scheme.

  5. Comparing the survival rate of juvenile Chinook salmon migrating through hydropower systems using injectable and surgical acoustic transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Z. D.; Martinez, J. J.; Li, H.; Harnish, R. A.; Woodley, C. M.; Hughes, J. A.; Li, X.; Fu, T.; Lu, J.; McMichael, G. A.; Weiland, M. A.; Eppard, M. B.; Skalski, J. R.; Townsend, R. L.

    2017-02-21

    Acoustic telemetry is one of the primary technologies for studying the behavior and survival of fishes throughout the world. The size and performance of the transmitters is still the key limiting factor despite that considerable effort has been expended to understand the biological effects of implantation of acoustic transmitters in yearling and subyearling Chinook salmon. The newly developed injectable transmitter is the first active acoustic tag that can be implanted via injection instead of surgery. It also lasts more than four times longer than the commercially-available transmitters. A two-part field study was conducted to evaluate the performance of the injectable transmitter and its effect on the survival of implanted fish. The injectable transmitter performed well and similarly to the other commercially-available transmitters tested. Snake River subyearling Chinook salmon smolts implanted with the injectable tag had a higher survival probability from release to each of 11 downstream detection arrays than concurrent releases of fish surgically implanted with commercially-available tags. In addition, reach-specific survival estimates were significantly higher for the injectable group in three of the eleven reaches examined. Overall, the injectable group had a 0.263 (SE = 0.017) survival probability over the entire 500 km study area compared to 0.199 (0.012) for the surgically implanted group. The differences in survival may have been caused by warm water temperatures and higher rates of infection experienced by the surgically implanted group due to the presence of sutures acting as an attachment site for pathogens. The reduction in size and ability to implant the new transmitter via injection has further reduced the tag or tagging effect bias associated with studying small fishes. The information gathered with this new technology is helping minimize the impact of dams on fish, leading to more environmentally sustainable energy systems.

  6. The timing of phasic transmitter release is Ca2+-dependent and lacks a direct influence of presynaptic membrane potential.

    Science.gov (United States)

    Felmy, Felix; Neher, Erwin; Schneggenburger, Ralf

    2003-12-09

    Ca2+ influx through voltage-gated Ca2+ channels and the resulting elevation of intracellular Ca2+ concentration, [Ca2+]i, triggers transmitter release in nerve terminals. However, it is controversial whether in addition to the opening of Ca2+ channels, membrane potential directly affects transmitter release. Here, we assayed the influence of membrane potential on transmitter release at the calyx of Held nerve terminals. Transmitter release was evoked by presynaptic Ca2+ uncaging, or by presynaptic Ca2+ uncaging paired with presynaptic voltage-clamp depolarizations to +80 mV, under pharmacological block of voltage-gated Ca2+ channels. Such a change in membrane potential did not alter the Ca2+ dependence of transmitter release rates or synaptic delays. We also found, by varying the amount of Ca2+ influx during Ca2+ tail-currents, that the time course of phasic transmitter release is not invariant to changes in release probability. Rather, the time difference between peak Ca2+ current and peak transmitter release became progressively shorter with increasing Ca2+ current amplitude. When this time difference was plotted as a function of the estimated local [Ca2+]i at the sites of vesicle fusion, a slope of approximately 100 micros per 10 microM [Ca2+]i was found, in reasonable agreement with a model of cooperative Ca2+ binding and vesicle fusion. Thus, the amplitude and time course of the [Ca2+]i signal at the sites of vesicle fusion controls the timing and the amount of transmitter release, both under conditions of brief periods of Ca2+ influx, as well as during step-like elevations of [Ca2+]i produced by Ca2+ uncaging.

  7. Role of glycogenolysis in stimulation of ATP release from cultured mouse astrocytes by transmitters and high K+ concentrations

    OpenAIRE

    Junnan Xu; Dan Song; Qiufang Bai; Lijun Zhou; Liping Cai; Leif Hertz; Liang Peng

    2014-01-01

    This study investigates the role of glycogenolysis in stimulated release of ATP as a transmitter from astrocytes. Within the last 20 years our understanding of brain glycogenolysis has changed from it being a relatively uninteresting process to being a driving force for essential brain functions like production of transmitter glutamate and homoeostasis of potassium ions (K+) after their release from excited neurons. Simultaneously, the importance of astrocytic handling of adenosine, its phosp...

  8. Single-Chip Fully Integrated Direct-Modulation CMOS RF Transmitters for Short-Range Wireless Applications

    Directory of Open Access Journals (Sweden)

    M. Jamal Deen

    2013-08-01

    Full Text Available Ultra-low power radio frequency (RF transceivers used in short-range application such as wireless sensor networks (WSNs require efficient, reliable and fully integrated transmitter architectures with minimal building blocks. This paper presents the design, implementation and performance evaluation of single-chip, fully integrated 2.4 GHz and 433 MHz RF transmitters using direct-modulation power voltage-controlled oscillators (PVCOs in addition to a 2.0 GHz phase-locked loop (PLL based transmitter. All three RF transmitters have been fabricated in a standard mixed-signal CMOS 0.18 µm technology. Measurement results of the 2.4 GHz transmitter show an improvement in drain efficiency from 27% to 36%. The 2.4 GHz and 433 MHz transmitters deliver an output power of 8 dBm with a phase noise of −122 dBc/Hz at 1 MHz offset, while drawing 15.4 mA of current and an output power of 6.5 dBm with a phase noise of −120 dBc/Hz at 1 MHz offset, while drawing 20.8 mA of current from 1.5 V power supplies, respectively. The PLL transmitter delivers an output power of 9 mW with a locking range of 128 MHz and consumes 26 mA from 1.8 V power supply. The experimental results demonstrate that the RF transmitters can be efficiently used in low power WSN applications.

  9. Synchrotron radiation facilities

    CERN Multimedia

    1972-01-01

    Particularly in the past few years, interest in using the synchrotron radiation emanating from high energy, circular electron machines has grown considerably. In our February issue we included an article on the synchrotron radiation facility at Frascati. This month we are spreading the net wider — saying something about the properties of the radiation, listing the centres where synchrotron radiation facilities exist, adding a brief description of three of them and mentioning areas of physics in which the facilities are used.

  10. Thermal distortion test facility

    Science.gov (United States)

    Stapp, James L.

    1995-02-01

    The thermal distortion test facility (TDTF) at Phillips Laboratory provides precise measurements of the distortion of mirrors that occurs when their surfaces are heated. The TDTF has been used for several years to evaluate mirrors being developed for high-power lasers. The facility has recently undergone some significant upgrades to improve the accuracy with which mirrors can be heated and the resulting distortion measured. The facility and its associated instrumentation are discussed.

  11. Materials Characterization Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Materials Characterization Facility enables detailed measurements of the properties of ceramics, polymers, glasses, and composites. It features instrumentation...

  12. Mobile Solar Tracker Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NIST's mobile solar tracking facility is used to characterize the electrical performance of photovoltaic panels. It incorporates meteorological instruments, a solar...

  13. Universal Drive Train Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This vehicle drive train research facility is capable of evaluating helicopter and ground vehicle power transmission technologies in a system level environment. The...

  14. Composite Structures Manufacturing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Composite Structures Manufacturing Facility specializes in the design, analysis, fabrication and testing of advanced composite structures and materials for both...

  15. Neutron Therapy Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Neutron Therapy Facility provides a moderate intensity, broad energy spectrum neutron beam that can be used for short term irradiations for radiobiology (cells)...

  16. Catalytic Fuel Conversion Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility enables unique catalysis research related to power and energy applications using military jet fuels and alternative fuels. It is equipped with research...

  17. Heated Tube Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Heated Tube Facility at NASA GRC investigates cooling issues by simulating conditions characteristic of rocket engine thrust chambers and high speed airbreathing...

  18. Engine Test Facility (ETF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Air Force Arnold Engineering Development Center's Engine Test Facility (ETF) test cells are used for development and evaluation testing of propulsion systems for...

  19. High Combustion Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL's High-Pressure Combustion Research Facility in Morgantown, WV, researchers can investigate new high-pressure, high-temperature hydrogen turbine combustion...

  20. Region 9 NPDES Facilities

    Data.gov (United States)

    U.S. Environmental Protection Agency — Point geospatial dataset representing locations of NPDES Facilities. NPDES (National Pollution Discharge Elimination System) is an EPA permit program that regulates...

  1. Geospatial Data Analysis Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Geospatial application development, location-based services, spatial modeling, and spatial analysis are examples of the many research applications that this facility...

  2. Geodynamics Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This GSL facility has evolved over the last three decades to support survivability and protective structures research. Experimental devices include three gas-driven...

  3. Imagery Data Base Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Imagery Data Base Facility supports AFRL and other government organizations by providing imagery interpretation and analysis to users for data selection, imagery...

  4. Pavement Testing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Comprehensive Environmental and Structural Analyses The ERDC Pavement Testing Facility, located on the ERDC Vicksburg campus, was originally constructed to provide...

  5. Nonlinear Materials Characterization Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Nonlinear Materials Characterization Facility conducts photophysical research and development of nonlinear materials operating in the visible spectrum to protect...

  6. Geophysical Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Geophysical Research Facility (GRF) is a 60 ft long qaodmasdkwaspemas5ajkqlsmdqpakldnzsdfls 22 ft wide qaodmasdkwaspemas4ajkqlsmdqpakldnzsdfls 7 ft deep concrete...

  7. Transonic Experimental Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Transonic Experimental Research Facility evaluates aerodynamics and fluid dynamics of projectiles, smart munitions systems, and sub-munitions dispensing systems;...

  8. Flexible Electronics Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Flexible Electronics Research Facility designs, synthesizes, tests, and fabricates materials and devices compatible with flexible substrates for Army information...

  9. DUPIC facility engineering

    Energy Technology Data Exchange (ETDEWEB)

    Park, J. J.; Lee, H. H.; Kim, K. H. and others

    2000-03-01

    The objectives of this study are (1) the refurbishment for PIEF(Post Irradiation Examination Facility) and M6 hot-cell in IMEF(Irradiated Material Examination Facility), (2) the establishment of the compatible facility for DUPIC fuel fabrication experiments which is licensed by government organization, and (3) the establishment of the transportation system and transportation cask for nuclear material between facilities. The report for this project describes following contents, such as objectives, necessities, scope, contents, results of current step, R and D plan in future and etc.

  10. Textiles Performance Testing Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Textiles Performance Testing Facilities has the capabilities to perform all physical wet and dry performance testing, and visual and instrumental color analysis...

  11. Joint Computing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Raised Floor Computer Space for High Performance Computing The ERDC Information Technology Laboratory (ITL) provides a robust system of IT facilities to develop and...

  12. GPS Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Global Positioning System (GPS) Test Facility Instrumentation Suite (GPSIS) provides great flexibility in testing receivers by providing operational control of...

  13. Magnetics Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Magnetics Research Facility houses three Helmholtz coils that generate magnetic fields in three perpendicular directions to balance the earth's magnetic field....

  14. Target Assembly Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Target Assembly Facility integrates new armor concepts into actual armored vehicles. Featuring the capability ofmachining and cutting radioactive materials, it...

  15. Facility Environmental Management System

    Data.gov (United States)

    Federal Laboratory Consortium — This is the Web site of the Federal Highway Administration's (FHWA's) Turner-Fairbank Highway Research Center (TFHRC) facility Environmental Management System (EMS)....

  16. Proximal Probes Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Proximal Probes Facility consists of laboratories for microscopy, spectroscopy, and probing of nanostructured materials and their functional properties. At the...

  17. Manufacturing Demonstration Facility (MDF)

    Data.gov (United States)

    Federal Laboratory Consortium — The U.S. Department of Energy Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory (ORNL) provides a collaborative, shared infrastructure to...

  18. Pavement Testing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Comprehensive Environmental and Structural AnalysesThe ERDC Pavement Testing Facility, located on the ERDC Vicksburg campus, was originally constructed to provide an...

  19. Fiber-based laser transmitter and laser spectroscopy of the oxygen A-band for remote detection of atmospheric pressure

    Science.gov (United States)

    Stephen, Mark Andrew

    The Author reports on the design and construction of an oxygen spectroscopy laser sounding instrument designed to measure atmospheric pressure. This instrument was conceived and designed with a satellite application in mind so we discuss the requirements this places on the instrument and specifically the laser transmitter. We have developed a novel, pulsed, frequency-doubled, fiber-based laser transmitter for use in the instrument. The instrument concept uses the collision broadening of spectroscopic lines of the diatomic oxygen A-band to deduce atmospheric pressure. We report on the spectroscopic and instrument theory. We discuss the development of a high-power, narrow-frequency, tunable, single spatial mode pulsed laser transmitter. The transmitter is a master oscillator power amplifier (MOPA) design. The master oscillator is a fiber coupled DFB laser with external acousto-optic modulation. The amplifier is a diode pumped, erbium-doped fiber. We discuss the non-linear optical effect of stimulated Brillouin scattering (SBS) and how it limits the transmitter performance. We review various methods for overcoming SBS in erbium fiber amplifiers and then demonstrate the performance of a high SBS threshold fiber amplifier. We demonstrate the efficacy of this transmitter by integrating it into a spectroscopic instrument and make atmospheric measurements at a test site at Goddard. We also discuss future improvements.

  20. DUPIC facility engineering

    Energy Technology Data Exchange (ETDEWEB)

    Park, J. J.; Lee, H. H.; Kim, K. H. [and others

    2002-03-01

    With starting DUPIC fuel fabrication experiment by using spent fuels, 1) operation and refurbishment for DFDF (DUPIC fuel development facility), and 2) operation and improvement of transportation equipment for radioactive materials between facilities became the objectives of this study. This report describes objectives of the project, necessities, state of related technology, R and D scope, R and D results, proposal for application etc.

  1. Samarbejdsformer og Facilities Management

    DEFF Research Database (Denmark)

    Storgaard, Kresten

    Resultater fra en surveyundersøgelse om fordele og ulemper ved forskellige samarbejdsformer indenfor Facilities Management fremlægges.......Resultater fra en surveyundersøgelse om fordele og ulemper ved forskellige samarbejdsformer indenfor Facilities Management fremlægges....

  2. Japan Hadron Facility

    CERN Document Server

    Hayano, R S

    1999-01-01

    Japan Hadron Facility (JHF) is a high-intensity proton accelerator complex consisting of a 200 MeV linac, a 3 GeV booster and a 50 GeV main ring. Its status and future possibilities of realizing a versatile antiproton facility at JHF are presented.

  3. Samarbejdsformer og Facilities Management

    DEFF Research Database (Denmark)

    Storgaard, Kresten

    Resultater fra en surveyundersøgelse om fordele og ulemper ved forskellige samarbejdsformer indenfor Facilities Management fremlægges.......Resultater fra en surveyundersøgelse om fordele og ulemper ved forskellige samarbejdsformer indenfor Facilities Management fremlægges....

  4. BIBLIOGRAPHY OF FACILITIES INFORMATION.

    Science.gov (United States)

    American Association of Junior Colleges, Washington, DC.

    PERSONNEL OF THE FACILITIES INFORMATION SERVICE OF THE AMERICAN ASSOCIATION OF JUNIOR COLLEGES COMPILED THIS LISTING OF BOOKS, ARTICLES, MONOGRAPHS, AND OTHER PRINTED MATERIALS RELEVANT TO JUNIOR COLLEGE FACILITIES PLANNING, DESIGN, AND CONSTRUCTION. IN ADDITION TO A "GENERAL" CATEGORY, REFERENCES ARE GROUPED UNDER HEADINGS OF AUDITORIUMS, COLLEGE…

  5. Evidence for a role of glutamate as an efferent transmitter in taste buds

    Directory of Open Access Journals (Sweden)

    Anderson Catherine B

    2010-06-01

    Full Text Available Abstract Background Glutamate has been proposed as a transmitter in the peripheral taste system in addition to its well-documented role as an umami taste stimulus. Evidence for a role as a transmitter includes the presence of ionotropic glutamate receptors in nerve fibers and taste cells, as well as the expression of the glutamate transporter GLAST in Type I taste cells. However, the source and targets of glutamate in lingual tissue are unclear. In the present study, we used molecular, physiological and immunohistochemical methods to investigate the origin of glutamate as well as the targeted receptors in taste buds. Results Using molecular and immunohistochemical techniques, we show that the vesicular transporters for glutamate, VGLUT 1 and 2, but not VGLUT3, are expressed in the nerve fibers surrounding taste buds but likely not in taste cells themselves. Further, we show that P2X2, a specific marker for gustatory but not trigeminal fibers, co-localizes with VGLUT2, suggesting the VGLUT-expressing nerve fibers are of gustatory origin. Calcium imaging indicates that GAD67-GFP Type III taste cells, but not T1R3-GFP Type II cells, respond to glutamate at concentrations expected for a glutamate transmitter, and further, that these responses are partially blocked by NBQX, a specific AMPA/Kainate receptor antagonist. RT-PCR and immunohistochemistry confirm the presence of the Kainate receptor GluR7 in Type III taste cells, suggesting it may be a target of glutamate released from gustatory nerve fibers. Conclusions Taken together, the results suggest that glutamate may be released from gustatory nerve fibers using a vesicular mechanism to modulate Type III taste cells via GluR7.

  6. Health Monitoring of Thick Materials Using Piezoceramic Patches, Time Signals, and Wavelet Transmittance Functions

    Directory of Open Access Journals (Sweden)

    D.R. Hughes

    2004-01-01

    Full Text Available A relatively overlooked factor in both global and local methods of health monitoring is the nonlinear stiffness of structures caused by the cycling of cracks and delaminations. Global methods of health monitoring use modal parameters or frequency response functions in an inverse procedure to quantify damage in structures with thick sections. Global approaches use fewer sensors that detect only significantly large damage in structures due to damage caused by transient vibration. However, local methods use Lamb wave propagation to detect small damage within a structure by an array of closely spaced sensors and actuators. Local methods also become more difficult to use on thick or non-homogeneous materials because wave propagation becomes complex. This paper develops a combined time series and wavelet analysis technique to improve damage detection in either thick, complex geometry, or non-homogeneous materials. A wavelet transmittance function (WTF is defined as the ratio of continuous wavelet transforms from the time responses at different locations on a structure. A new damage indicator was developed based upon wavelet transmittance function. The novelty of the method lies in the fact that a near real time inference about the damage and the approximate extent of damage can be drawn without historical data. A simulated model is illustrated to highlight the potential of the new damage indicator on a thick aluminum specimen. Then, experimental signal data from two sets of different experiments conducted on thick structures with a crack and a delamination were analyzed using the wavelet transmittance function to detect the presence and extent of the damages as reflected on the WTF maps. This paper mainly deals with the development of WTF and the associated damage indicator by analyzing the simulated and experimental sets of data.

  7. Biotelemetry transmitter implantation in rodents: impact on growth and circadian rhythms.

    Science.gov (United States)

    Leon, Lisa R; Walker, Larry D; DuBose, David A; Stephenson, Lou A

    2004-05-01

    The implantation of a biotelemetry transmitter for core body temperature (T(c)) and motor activity (MA) measurements is hypothesized to have effects on growth and circadian rhythmicity depending on animal body-to-transmitter (B:T) size ratio. This study examined the impact of transmitter implantation (TM) on body weight, food intake (FI), water intake (WI), and circadian T(c) and MA rhythms in mice (23.8 +/- 0.04 g) and rats (311.5 +/- 5.1 g) receiving no treatment (NT), anesthesia, laparotomy (LAP), and TM. The B:T size ratio was 6:1 and 84:1 for mice and rats, respectively. In mice, body weight required 14 days to recover to presurgical levels and never attained the level of the other groups. FI recovered in 3 days, whereas WI never reached presurgical levels. Rat body weight did not decrease below presurgical levels. FI and WI recovered to presurgical levels in rats by day 2 postsurgery. Anesthesia decreased mouse body weight for 1 wk, but was without effect in rats. LAP significantly decreased body weight for 5 days in mice and 1 day in rats, showing a significant effect of the surgical procedure in the absence of TM in both species. Circadian T(c) and MA rhythms were evident within the first week in both species, indicating dissociation between circadian rhythmicity and recovery of growth variables. Cosinor analysis showed a TM effect on T(c) min, T(c) max, mesor, amplitude, and period of mice, whereas only the amplitude of the rhythm was affected in rats. These data indicate that a large B:T size ratio is associated with minimization of the adverse effects of surgical implantation. We recommend that B:T size ratio, recovery of presurgical body weight, and display of a robust circadian T(c) and MA rhythm be established before collection of biotelemetry data collection under an experimental paradigm.

  8. Changes in transmitter release patterns in vitro induced by tremorgenic mycotoxins.

    Science.gov (United States)

    Bradford, H F; Norris, P J; Smith, C C

    1990-01-01

    The neurochemical effects of the tremorgenic mycotoxins Verruculogen and Penitrem A, which produce a neurotoxic syndrome characterized by sustained tremors, were studied using sheep and rat synaptosomes. The toxins were administered in vivo, either by chronic feeding (sheep) or ip injection 45 min prior to sacrifice (rat). Synaptosomes were subsequently prepared from cerebrocortical and spinal cord/medullary regions of rat, and corpus striatum of sheep. Penitrem A (400 mg mycelium/kg) increased the spontaneous release of endogenous glutamate, GABA, and aspartate by 213%, 455%, and 227%, respectively, from cerebrocortical synaptosomes. Verruculogen (400 mg mycelium/kg) increased the spontaneous release of glutamate and aspartate by 1,300% and 1,200% respectively, but not that of GABA, from cerebrocortical synaptosomes. The spontaneous release of the transmitter amino acids or other amino acids was not increased by the tremorgens in spinal cord/medullary synaptosomes. Penitrem A pretreatment reduced the Veratrine (75 microM) stimulated release of glutamate, aspartate and GABA from cerebrocortical synaptosomes by 33%, 46%, and 11% respectively, and the stimulated release of glycine and GABA from spinal cord/medulla synaptosomes by 67% and 32%, respectively. Verruculogen pretreatment did not alter the Veratrine-induced release of transmitter amino acids from cerebrocortex and spinal cord/medulla synaptosomes. Penitrem A pretreatment increased the spontaneous release of aspartate, glutamate and GABA by 68%, 62%, and 100%, respectively, from sheep corpus striatum synaptosomes but did not alter the synthesis and release of dopamine in this tissue. Verruculogen was shown to cause a substantial increase (300-400%) in the miniature-end-plate potential frequency at the locust neuromuscular junction. The response was detectable within 1 min, rose to a maximum within 5-7 min, and declined to the control rate over a similar period. No change in the amplitude of the m.e.p.p.s was

  9. Measurement of soluble solids content in watermelon by Vis/NIR diffuse transmittance technique

    Institute of Scientific and Technical Information of China (English)

    TIAN Hai-qing; YING Yi-bin; LU Hui-shan; FU Xia-ping; YU Hai-yan

    2007-01-01

    Watermelon is a popular fruit in the world with soluble solids content (SSC) being one of the major characteristics used for assessing its quality. This study was aimed at obtaining a method for nondestructive SSC detection of watermelons by means of visible/near infrared (Vis/NIR) diffuse transmittance technique. Vis/NIR transmittance spectra of intact watermelons were acquired using a low-cost commercially available spectrometer operating over the range 350~1000 nm. Spectra data were analyzed by two multivariate calibration techniques: partial least squares (PLS) and principal component regression (PCR)methods. Two experiments were designed for two varieties of watermelons [Qilin (QL), Zaochunhongyu (ZC)], which have different skin thickness range and shape dimensions. The influences of different data preprocessing and spectra treatments were also investigated. Performance of different models was assessed in terms of root mean square errors of calibration (RMSEC), root mean square errors of prediction (RMSEP) and correlation coefficient (r) between the predicted and measured parameter values.Results showed that spectra data preprocessing influenced the performance of the calibration models. The first derivative spectra showed the best results with high correlation coefficient of determination [r=0.918 (QL); r=0.954 (ZC)], low RMSEP [0.65 °Brix(QL); 0.58 °Brix (ZC)], low RMSEC [0.48 °Brix (QL); 0.34 °Brix (ZC)] and small difference between the'RMSEP and the RMSEC by PLS method. The nondestructive Vis/NIR measurements provided good estimates of SSC index of watermelon, and the predicted values were highly correlated with destructively measured values for SSC. The models based on smoothing spectra(Savitzky-Golay filter smoothing method) did not enhance the performance of calibration models obviously. The results indicated the feasibility of Vis/NIR diffuse transmittance spectral analysis for predicting watermelon SSC in a nondestructive way.

  10. A SIEPON based transmitter sleep mode energy-efficient mechanism in EPON

    Science.gov (United States)

    Nikoukar, AliAkbar; Hwang, I.-Shyan; Wang, Chien-Jung; Ab-Rahman, Mohammad Syuhaimi; Liem, Andrew Tanny

    2015-06-01

    The main energy consumption in computer networks is the access networks. The passive optical network (PON) has the least energy consumption among access network technologies. In addition, the time division multiplexing (TDM) Ethernet PON (EPON) is one of the best candidates to improve energy consumption by time utilization. The optical network unit (ONU) can utilize the time and save the energy in the EPON by turning off its transmitter/receiver when there is no upstream/downstream traffic. The ITU-T and IEEE organizations are published standards for energy-saving in the TDM-PON. Although their standards provide the framework to accomplish the energy-saving, the algorithms/criteria to generate events to accommodate various operational policies, time to wake up, parameter values for timers are out of scope of the standards. Many studies have proposed schemes for energy-saving in TDM-PON to achieve maximum energy saving. Even so, these schemes increase the mean packet delay and consequently, reduce the quality of service (QoS). In this paper, first we take a look to the state of the art for PON energy-saving. Additionally, a mechanism based on SIEPON standard in EPON with new components in the ONUs and optical line terminal (OLT) is proposed to save the transmitter energy and guarantee QoS. The proposed mechanism follows the SIEPON standard, considers the QoS first, and then saves the energy as far as possible. The ONU sleep controller unit (OSC) and green dynamic bandwidth allocation (GDBA) are used to calculate the ONU transmitter sleep (Tx) duration and grant the proper time to the ONUs. Simulation results show that the proposed energy-saving mechanism not only promises the QoS performance in terms of mean packet delay, packet loss, throughput, and jitter, but also saves energy in different maximum cycle times.

  11. Estimating Leaf Water Status from Vis-Nir Reflectance and Transmittance

    Science.gov (United States)

    Vanderbilt, Vern; Daughtry, Craig; Dahlgren, Robert

    2017-01-01

    Remotely sensing the water status of plant canopies remains a long term goal of remote sensing research. Established approaches involve measurements in the thermal infrared and the 900-2000nm reflective infrared. Less popular UV-visible-NIR techniques presumably deserve research attention, because photochemical changes linked to plant water status manifest spectral light scattering and absorption changes. Here we monitored the visible and NIR light reflected from the leaf interior as well as the leaf transmittance as the relative water content of corn (Zeamays L.) leaves decreased. Our results highlight the importance of both scattering effects and effects due to absorption by leaf pigments.

  12. Optical antenna gain. III - The effect of secondary element support struts on transmitter gain

    Science.gov (United States)

    Klein, B. J.; Degnan, J. J.

    1976-01-01

    The effect of a secondary-element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three- and four-support members.

  13. Optical antenna gain. 3: The effect of secondary element support struts on transmitter gain.

    Science.gov (United States)

    Klein, B J; Degnan, J J

    1976-04-01

    The effect of a secondary element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three and four support members.

  14. The infrared spectral transmittance of Aspergillus niger spore aggregated particle swarm

    Science.gov (United States)

    Zhao, Xinying; Hu, Yihua; Gu, Youlin; Li, Le

    2015-10-01

    Microorganism aggregated particle swarm, which is quite an important composition of complex media environment, can be developed as a new kind of infrared functional materials. Current researches mainly focus on the optical properties of single microorganism particle. As for the swarm, especially the microorganism aggregated particle swarm, a more accurate simulation model should be proposed to calculate its extinction effect. At the same time, certain parameters deserve to be discussed, which helps to better develop the microorganism aggregated particle swarm as a new kind of infrared functional materials. In this paper, take Aspergillus Niger spore as an example. On the one hand, a new calculation model is established. Firstly, the cluster-cluster aggregation (CCA) model is used to simulate the structure of Aspergillus Niger spore aggregated particle. Secondly, the single scattering extinction parameters for Aspergillus Niger spore aggregated particle are calculated by using the discrete dipole approximation (DDA) method. Thirdly, the transmittance of Aspergillus Niger spore aggregated particle swarm is simulated by using Monte Carlo method. On the other hand, based on the model proposed above, what influences can wavelength causes has been studied, including the spectral distribution of scattering intensity of Aspergillus Niger spore aggregated particle and the infrared spectral transmittance of the aggregated particle swarm within the range of 8~14μm incident infrared wavelengths. Numerical results indicate that the scattering intensity of Aspergillus Niger spore aggregated particle reduces with the increase of incident wavelengths at each scattering angle. Scattering energy mainly concentrates on the scattering angle between 0~40°, forward scattering has an obvious effect. In addition, the infrared transmittance of Aspergillus Niger spore aggregated particle swarm goes up with the increase of incident wavelengths. However, some turning points of the trend

  15. Adaptive Compensation of the Nonlinear Distortions in Optical Transmitters Using Predistortion

    Directory of Open Access Journals (Sweden)

    O. Panagiev

    2008-12-01

    Full Text Available The described method refers to compensation of nonlinear distortions, originating in laser diodes, used in wideband SCM-communication systems. Its essence is presenting in forming of a function that is opposite of the function describing the W-A characteristic of the emitting diode. Main element is the predistorter, which is connected in series before the emitting diode. This way, an improving of the optical transmitter’s parameters and characteristics is being realized, by using a purposive entering predistortion.

  16. Measuring Transmittance in Rubidium Vapour Cells Using an Extremely Weak Coherent Field of Light

    Institute of Scientific and Technical Information of China (English)

    邓见辽; 黎永青; 王育竹

    2003-01-01

    The absorptive properties of the atomic transition in the Rb85 D2 (A) line (5S1/2-5Pa/2) at 780.0 nm are measured by using a continuous tunable diode laser and a CCD detector in Rb vapour cell under the condition of extremely weak incident intensity. When the intensity of incident light decreases from 420pW/cm2 to 0.03pW/cm2, the transmittance is found to be independent of the incident intensity within our experimental accuracy.

  17. Information Theoretic Exemplification of the Impact of Transmitter-Receiver Cognition on the Channel Capacity

    CERN Document Server

    Anzabi-Nezhad, Nima S; Kakhki, Mohammad Molavi

    2011-01-01

    In this paper, we study, information theoretically, the impact of transmitter and or receiver cognition on the channel capacity. The cognition can be described by state information, dependent on the channel noise and or input. Specifically, as a new idea, we consider the receiver cognition as a state information dependent on the noise and we derive a capacity theorem based on the Gaussian version of the Cover-Chiang capacity theorem for two-sided state information channel. As intuitively expected, the receiver cognition increases the channel capacity and our theorem shows this increase quantitatively. Also, our capacity theorem includes the famous Costa theorem as its special cases.

  18. Energy-Efficient Power Allocation of Cognitive Radio Systems without CSI at the Transmitter

    KAUST Repository

    Sboui, Lokman

    2015-01-07

    Two major issues are facing today’s wireless communications evolution: -Spectrum scarcity: Need for more bandwidth. As a solution, the Cognitive Radio (CR) paradigm, where secondary users (unlicensed) share the spectrum with licensed users, was introduced. -Energy consumption and CO2 emission: The ICT produce 2% of global CO2 emission (equivalent to the aviation industry emission). The cellular networks produces 0.2%. As solution energy efficient systems should be designed rather than traditional spectral efficient systems. In this work, we aim to determine the optimal energy efficient power allocation of CR when the channel state information at the transmitter CSI-T is not available.

  19. Development of a Pulsed 2-micron Laser Transmitter for CO2 Sensing from Space

    Science.gov (United States)

    Singh, Upendra N.; Yu, Jirong; Bai, Yingxin; Petros, Mulugeta; Menzies, Robert T.

    2011-01-01

    NASA Langley Research Center (LaRC), in collaboration with NASA Jet Propulsion Laboratory (JPL), is engaged in the development and demonstration of a highly efficient, versatile, 2-micron pulsed laser that can be used in a pulsed Differential Absorption Lidar (DIAL)/Integrated Path Differential Absorption (IPDA) instrument to make precise, high-resolution CO2 measurements to investigate sources, sinks, and fluxes of CO2. This laser transmitter will feature performance characteristics needed for an ASCENDS system that will be capable of delivering the CO2 measurement precision required by the Earth Science Decadal Survey (DS).

  20. METC Combustion Research Facility

    Energy Technology Data Exchange (ETDEWEB)

    Halow, J.S.; Maloney, D.J.; Richards, G.A.

    1993-11-01

    The objective of the Morgantown Energy Technology Center (METC) high pressure combustion facility is to provide a mid-scale facility for combustion and cleanup research to support DOE`s advanced gas turbine, pressurized, fluidized-bed combustion, and hot gas cleanup programs. The facility is intended to fill a gap between lab scale facilities typical of universities and large scale combustion/turbine test facilities typical of turbine manufacturers. The facility is now available to industry and university partners through cooperative programs with METC. High pressure combustion research is also important to other DOE programs. Integrated gasification combined cycle (IGCC) systems and second-generation, pressurized, fluidized-bed combustion (PFBC) systems use gas turbines/electric generators as primary power generators. The turbine combustors play an important role in achieving high efficiency and low emissions in these novel systems. These systems use a coal-derived fuel gas as fuel for the turbine combustor. The METC facility is designed to support coal fuel gas-fired combustors as well as the natural gas fired combustor used in the advanced turbine program.